Bartoli, C.R., K. Okabe, I. Akiyama, B. Coull, and J.J. Godleski (2008). Repeat microsphere delivery for serial measurement of regional blood perfusion in the chronically instrumented, conscious canine. Journal of Surgical Research 145(1): 135-41. ISSN: 0022-4804.
Abstract: INTRODUCTION: For chronic, repeat hemodynamic studies in conscious dogs, we designed and tested a chronically instrumented canine microsphere delivery model. The goals of this study were (1) to investigate the accuracy of repeated estimations of blood perfusion using fluorescent-labeled microspheres and (2) to develop and validate a chronic preparation that permits consecutive estimations in the same conscious animal over an extended protocol. METHODS: Via thoracotomy, nine dogs were instrumented with left atrial appendage and aortic vascular access catheters connected to subcutaneous vascular access ports. Four animals received seven serial injections of 1.6 million 15 microm microspheres (total: 11.2 million), and five animals received 8 serial injections of 2.25 million microspheres (total: 18 million) over the course of 11 or 18 wk. RESULTS: All catheters have remained bidirectionally patent during protocol for 14.9 +/- 0.8 (mean +/- SEM) wk. Sphere accumulation did not significantly alter global myocardial (P = 0.69, P = 0.25), renal (P = 0.92, P = 0.12), hepatic (P = 0.84, P = 0.32), or splenic (P = 0.33, P = 0.70) blood perfusion in either set of animals. CONCLUSIONS: Catheters remained bidirectionally patent for months, did not interfere with the hemodynamic responses of the preparation, and allowed repeat percutaneous injection of microspheres and withdrawal of reference arterial blood from within conscious canines. Eight serial injections totaling 18 million microspheres over 18 weeks did not alter regional myocardial, hepatic, renal, or splenic blood flow. This dependable, chronic, percutaneous arterial access preparation provides a means for examining acute and long-term effects of pathophysiological, pharmaceutical, and environmental influences on regional arterial blood flow in conscious, large animals.
Descriptors: arteries physiology, catheters, indwelling, consciousness physiology, infusions, intra arterial methods, microspheres, coronary vessels physiology, dogs, infusions, intra arterial instrumentation, kidney blood supply, liver blood supply, models, animal, regional blood flow physiology, spleen blood supply, time factors.
Boswood, A. and A. Murphy (2006). The effect of heart disease, heart failure and diuresis on selected laboratory and electrocardiographic parameters in dogs. Journal of Veterinary Cardiology 8(1): 1-9. ISSN: 1760-2734.
NAL Call Number: SF811
Abstract: Objectives: To evaluate the influence of heart disease and heart failure on 9 parameters: the serum sodium, potassium, chloride, creatinine and urea concentrations, heart rate, vaso-vagal tonus index (VVTI), red cell number and hematocrit. Background: Previous studies have demonstrated that heart disease, heart failure and their treatment are associated with changes in laboratory and electrocardiographic parameters. Animals, materials and methods: Data were retrieved from 92 client-owned dogs with naturally occurring heart disease. Dogs were classified according to the severity of their heart disease and or the presence of heart failure. The effects of heart disease, the progression into heart failure, the initiation of successful therapy and the administration of diuretics on these parameters were determined. Results: Worse heart failure was characterized by the following changes: a significant fall in serum sodium and chloride concentrations and VVTI, and a significant increase in the serum urea concentration and heart rate. The onset of heart failure was characterized by a fall in VVTI and chloride concentration. The successful treatment of heart failure was characterized by a fall in heart rate, an increase in creatinine and sodium concentrations. Dogs receiving diuretics had higher heart rates, lower VVTI, higher urea concentrations, lower potassium, sodium and chloride concentrations. Conclusions: Numerous complex alterations in some of the studied parameters are associated with heart disease, heart failure and their treatment. Further consideration of these changes may improve our skills in diagnosis, prognostication and treatment..
Descriptors: blood composition, creatinine, diagnosis, diuresis, electrocardiography , haematocrit, heart, heart diseases, heart rate, medical treatment, potassium, potassium chloride, sodium, urea.
Chaprazov, T. (2006). Changes in some clinical and laboratory indices in dogs with experimental Staphylococcus aureus sepsis. Bulgarian Journal of Veterinary Medicine 9(1): 51-60. ISSN: 1311-1477.
Abstract: The study was conducted in 6 clinically healthy dogs that were experimentally infected via intravenous injection of 5 mL broth culture of a field Staphylococcus aureus strain (1.2x109 cells/mL). The dynamics of rectal temperature, heart and respiratory rates and haematological parameters (erythrocyte counts, haematocrit, haemoglobin, erythrocyte sedimentation rate, total and differential leukocyte counts, total protein, fibrinogen, bilirubin, urea, creatinine, pyruvate and lactate) were observed for 28-day period. It was observed that after 2 h of post-infection an increase in body temperature, tachycardia and tachypnea occurred. Followed by a marked leukopenia with an increased leukocyte counts at the 24th h with a left shift were noticed. Statistically significant increased in the values of blood biochemical parameters were observed for fibrinogen and bilirubin, while the concentrations of pyruvate decreased. The levels of total protein, creatinine, urea and lactate remained stable without significant deviations during the entire period of the survey.
Descriptors: bilirubin, blood chemistry, body temperature, clinical aspects, creatinine, disease markers, erythrocytes, experimental infections, fibrinogen, hematocrit, hematology, hemoglobin, heart rate, lactic acid, leukocytes, leukopenia, pathogenesis, pyruvic acid, respiration, septicemia, urea, dogs, Staphylococcus aureus.
Chuah, M.K.L., G. Schiedner, L. Thorrez, B. Brown, M. Johnston, V. Gillijns, S. Hertel, N. Van Rooijen, D. Lillicrap, D. Collen, T. Vandendriessche, and S. Kochanek (2003). Therapeutic factor viii levels and negligible toxicity in mouse and dog models of hemophilia a following gene therapy with high-capacity adenoviral vectors. Blood 101(5): 1734-1743. ISSN: 0006-4971.
NAL Call Number: RB145.A1B57
Abstract: High-capacity adenoviral (HC-Ad) vectors expressing B-domain-deleted human or canine factor VIII from different liver-specific promoters were evaluated for gene therapy of hemophilia A. Intravenous administration of these vectors into hemophilic FVIII-deficient immunodeficient SCID mice (FVIIIKO-SCID) at a dose of 5X109 infectious units (IU) resulted in efficient hepatic gene delivery and long-term expression of supraphysiologic FVIII levels (exceeding 15 000 mU/mL), correcting the bleeding diathesis. Injection of only 5X107 IU still resulted in therapeutic FVIII levels. In immunocompetent hemophilic FVIII-deficient mice (FVIIIKO), FVIII expression levels peaked at 75 000 mU/mL but declined thereafter because of neutralizing anti-FVIII antibodies and a cellular immune response. Vector administration did not result in thrombocytopenia, anemia, or elevation of the proinflammatory cytokine interleukin-6 (IL-6) and caused no or only transient elevations in serum transaminases. Following transient in vivo depletion of macrophages before gene transfer, significantly higher and stable FVIII expression levels were observed. Injection of only 5X106 HC-Ad vectors after macrophage depletion resulted in long-term therapeutic FVIII levels in the FVIIIKO and FVIIIKO-SCID mice. Intravenous injection of an HC-Ad vector into a hemophilia A dog at a dose of 4.3X109 IU/kg led to transient therapeutic canine FVIII levels that partially corrected whole-blood clotting time. Inhibitory antibodies to canine FVIII could not be detected, and there were no signs of hepatotoxicity or of hematologic abnormalities. These results contribute to a better understanding of the safety and efficacy of HC-Ad vectors and suggest that the therapeutic window of HC-Ad vectors could be improved by minimizing the interaction between HC-Ad vectors and the innate immune system.
Descriptors: blood and lymphatics, transport and circulation, genetics, molecular genetics, biochemistry and molecular biophysics, hemophilia A, blood and lymphatic disease, genetic disease, gene therapy, genetic techniques, laboratory techniques.
Driessen, B., J.S. Jahr, F. Lurie, M.S. Golkaryeh, and R.A. Gunther (2003). Arterial oxygenation and oxygen delivery after hemoglobin-based oxygen carrier infusion in canine hypovolemic shock: a dose-response study. Critical Care Medicine. 31(6): 1771-9. ISSN: 0090-3493.
Abstract: OBJECTIVE: To compare effects of 6% hetastarch (Hextend) and hemoglobin-based oxygen carrier hemoglobin glutamer-200 (Hb-200) (bovine; Oxyglobin) on hemodynamics, arterial oxygen content, and systemic oxygen delivery in a canine hemorrhagic shock model. DESIGN: Randomized laboratory investigation. SETTING: University surgical research facility. SUBJECTS: Twenty-four anesthetized healthy, adult, mongrel dogs (28 +/- 1 kg; 7 female, 17 male). INTERVENTIONS: Dogs were instrumented for determinations of heart rate, arterial, central venous, pulmonary arterial, and pulmonary arterial occlusion pressures, and cardiac index. Total solids, colloid oncotic pressure, arterial oxygen content, Hb, lactate, pH, and blood gases were analyzed in blood samples. Recordings were made before, after 1 hr of hemorrhagic shock, and immediately and 3 hrs after infusion of either 30 mL/kg hetastarch (group 1), 10 mL/kg Hb-200 + 20 mL/kg hetastarch (group 2), 20 mL/kg Hb-200 + 10 mL/kg hetastarch (group 3), or 30 mL/kg Hb-200 (group 4). MEASUREMENTS AND MAIN RESULTS: Hemorrhage (35 +/- 1 mL/kg) reduced mean arterial pressure to 50 mm Hg and caused significant decreases in total Hb, mean pulmonary arterial pressure, cardiac index and systemic oxygen delivery, increases in heart rate and systemic vascular resistance, and lactic acidosis. In group 1, hetastarch infusion was accompanied by increases of pulmonary arterial pressure, cardiac index, and blood oxygen extraction above baseline, and decreases of systemic vascular resistance, total Hb, total solids, arterial oxygen content, and systemic oxygen delivery below baseline (p <.05). Other data returned to baseline. In groups 2 to 4, hemodynamic functions (except pulmonary arterial pressure) recovered, yet neither total Hb (i.e., plasma and red blood cell Hb) nor arterial oxygen content increased despite increases in plasma Hb of 2 to 5 g/dL and proportionate increases in total solids. Systemic oxygen delivery improved dose-dependently with Hb-200 but did not return to baseline (p <.05), reaching values comparable to hetastarch group only at 30 mL/kg Hb-200. In all groups, oxygen extraction remained above baseline. Metabolic acidosis and lactatemia resolved significantly faster in groups 2 to 4, and colloid oncotic pressure after resuscitation was greater in groups 2 to 4 than in controls (p <.05). CONCLUSIONS: In hemorrhagic shock, Hb-200 infusion may not improve oxygen delivery more than hetastarch, likely due to hemodilution caused by its high colloid oncotic pressure, but may facilitate diffusive oxygen transport to tissues.
Descriptors: healthy, adult, mongrel dogs, canine hemorrhagic shock model, hemoglobin-based oxygen carrier, hemodynamics, arterial oxygen.
Driessen, B., J.S. Jahr, F. Lurie, and R.A. Gunther (2003). Effects of resuscitation with hemoglobin glutamer-200 (bovine) on systemic and mesenteric oxygen delivery in a canine hemorrhagic shock model: a comparison with 6 % hetastarch and shed blood. In: 2003 Annual Meeting of the American Society of Anesthesiologists: Abstracts of Scientific Papers, October 11-15, 2003, San Francisco, CA, USA, Abstract No. A 398.
Abstract: Introduction: Perfusion and thus O2 supply of the gut diminishes rapidly during hemorrhagic shock, exposing this organ to an increased risk of irreversible hypoxic damage. Hypovolemic resuscitation with Hemoglobin glutamer-200 (Hb-200) has been shown to improve many hemodynamic parameters including mesenteric arterial blood flow (MAF) but failed to restore systemic and mesenteric O2 delivery, while normovolemic shed blood resuscitation did (Driessen et al. Br J Anaesth 2001; 86:683-92). Since hypovolemic shock treatment aimed at restoring O2 transport rather than hemodynamic parameters improves outcome, we studied the efficacy of a larger dose of Hb-200 in comparison with whole blood (WB) and 6 % hetastarch (HES) infusion. Methods: Twelve anesthetized dogs (29 +- 1 kg) were instrumented for recordings of heart rate (HR), mean arterial (MAP) and central venous pressures (CVP), cardiac output, and MAF. Hemoglobin (Hb), O2 content (O2ct), lactate, pH, and blood gases were analyzed in arterial, mixed and mesenteric venous blood samples. Indexes for cardiac output (CI), MAF (MAFI), systemic (sDO2I) and mesenteric O2 delivery (mDO2I), systemic (sO2Ex) and mesenteric O2 extraction ratios (mO2Ex) were calculated. Recordings were made before (baseline), after 1 h of hemorrhage, and immediately and 3 h after resuscitation with 30 mL/kg of either Hb-200, HES, or shed WB. Data analysis included ANOVA plus Dunnett's and Tukey's tests (P < 0.05). Results: Hemorrhage (average 34 +- 2 mL/kg = 40 % blood loss) decreased MAP, CVP, CI, MAFI, sDO2I, mDO2I, total Hb, and arterial O2ct by average 49, 72, 59, 51, 70, 64, 22, and 26 %, respectively and increased HR, sO2Ex and mO2Ex by average 129, 190, and 200 %, respectively (P<0.05). Only WB transfusion restored all hemodynamic, hematological, oxygenation, and acid-base variables at 3 h post treatment. Hb-200 infusion returned most hemodynamic parameters including CI and MAFI to baseline but increased MAP above baseline (P<0.05). CVP was greater than in the WB group (P<0.05). Hb-200 infusion failed to restore total Hb and arterial O2ct; therefore, sDO2I and mDO2I as well as mixed-venous O2ct and mesenteric venous O2ct remained below baseline (P<0.05). Nevertheless, all systemic and mesenteric acid-base variables recovered after Hb-200 resuscitation. In the HES group, HR and MAFI returned to baseline, but MAP remained below and CI above baseline following resuscitation (P<0.05). HES further decreased total Hb and arterial O2ct, thereby preventing complete recovery of sDO2I and mDO2I (P<0.05). Thus, sO2Ex and mO2Ex stayed above baseline (P<0.05). Also in this group systemic and mesenteric acid-base variables recovered to baseline, yet slower than in the other two groups. Post resuscitation, HES and Hb-200 groups did not differ significantly with respect to total Hb, arterial O2ct, or sDO2I and mDO2I. Still, lactic acidosis resolved faster after Hb-200 than HES infusion (P<0.05). Conclusion: In canine hemorrhagic shock, isovolemic resuscitation with hemoglobin-based oxygen carriers such as Hb-200 may not improve arterial O2ct or systemic and mesenteric O2 delivery more so than HES, but may resolve systemic and mesenteric metabolic acidosis more rapidly than HES due to facilitated O2 transport to tissues. While potentially superior to non-Hb colloids (HES), Hb-200 is not equally effective with WB resuscitation.
Descriptors: pharmacology, respiratory system, respiration, hemorrhagic shock, nervous system disease, vascular disease, mesenteric oxygen delivery, clinical techniques, therapeutic and prophylactic techniques, resuscitation, systemic oxygen delivery, cardiac output, central venous pressure, heart rate, mean arterial pressure, mesenteric arterial blood flow.
Dubin, A., E. Estenssoro, G. Murias, H. Canales, P. Sottile, J. Badie, M. Baran, F. Palizas, M. Laporte, and M. Rivas Diaz (2001). Effects of hemorrhage on gastrointestinal oxygenation. Intensive Care Medicine 27(12): 1931-1936. ISSN: 0342-4642.
Abstract: OBJECTIVES: (1) To demonstrate that metabolic parameters are better indicators of tissue hypoxia than regional and whole oxygen consumption (VO(2)). (2) To compare intramucosal pH (pHi) in different gastrointestinal segments. DESIGN: Prospective, interventional study. SETTING: Research laboratory at a university center. SUBJECTS: Fourteen anesthetized, mechanically ventilated dogs. INTERVENTIONS: Twenty milliliters per kilogram bleeding. MEASUREMENTS AND MAIN RESULTS: We placed pulmonary, aortic and mesenteric venous catheters, and an electromagnetic flow probe in the superior mesenteric artery, and gastric, jejunal and ileal tonometers to measure flows, arterial and venous blood gases and lactate, and intramucosal PCO(2). We calculated systemic and intestinal oxygen transport (DO(2)) and consumption (VO(2)), pHi and arterial minus intramucosal PCO(2) (DeltaPCO(2)). Then, we bled the dogs and repeated the measurements after 30 min. Systemic and intestinal DO(2) fell (26.0+/-7.3 versus 8.9+/-2.6 and 71.9+/-17.3 versus 24.6+/-9.6 ml/min per kg, respectively, p<0.0001). Systemic and intestinal VO(2) remained unchanged (5.5+/-1.3 versus 5.4+/-1.3 and 15.7+/-5.0 versus 14.9+/-5.3 ml/min per kg, respectively). Gastric, jejunal and ileal pHi (7.13+/-0.11 versus 6.96+/-0.17, 7.18+/-0.06 versus 6.97+/-0.15, 7.12+/-0.11 versus 6.94+/-0.14, p<0.05) and DeltaPCO(2) (21+/-13 versus 35+/-23, 15+/-5 versus 33+/-16, 23+/-17 versus 38+/-20, p<0.05) changed accordingly. Arterial and mesenteric venous lactate and their difference, rose significantly (1.7+/-0.9 versus 3.7+/-1.4 and 1.8+/-0.8 versus 4.3+/-1.5 mmol/l, 0.1+/-0.6 versus 0.6+/-0.7 mmol/l, p<0.05). CONCLUSIONS: During hemorrhage, systemic and intestinal VO(2) remained stable. However, hyperlactatemia and intramucosal acidosis evidenced anaerobic metabolism. pHi changes paralleled in the three intestinal segments.
Descriptors: animal model, tissue hypoxia, hemorrhage, pH changes, gastrointestinal segments.
Friedman, Z., H. Berkenstadt, S. Preisman, and A. Perel (2003). A comparison of lactated ringer's solution to hydroxyethyl starch 6% in a model of severe hemorrhagic shock and continuous bleeding in dogs. Anesthesia and Analgesia 96(1): 39-45. ISSN: 0003-2999.
Abstract: In this randomized, controlled study in dogs, we examined the short-term effects of blood pressure targeted fluid resuscitation with colloids or crystalloids solutions on systemic oxygen delivery, and lactate blood concentration. Fluid resuscitation using hydroxyethyl starch (HES) 6% to a mean arterial blood pressure (MAP) of 60 mm Hg was compared with lactated Ringer's solution (LR) to a MAP of 60 or 80 mm Hg (LR60 and LR80, respectively). The model was one of withdrawal of blood to a MAP of 40 mm Hg through an arterial catheter that was then connected to a system allowing bleeding to occur throughout the study whenever MAP exceeded 40 mm Hg. Target MAP was maintained for 60 min with a continuous infusion of the designated fluid replacement. All 15 dogs (5 in each group) survived until the last measurement. Blood loss in the LR80 group (2980+-503 mL) (all values mean+-SD) was larger than in the LR60 and HES60 groups (1800+-389 mL, and 1820+-219 mL, respectively) (P<0.001). Whereas 840+-219 mL of HES60 was needed to maintain target MAP, 1880+-425 mL of LR was needed in the LR60 group, and 4590+-930 mL in the LR80 group (P<0.001). Lactate blood concentrations were smaller and delivered O2 higher in the HES60 group (35+-17 mg/dL and 239+-61 mL/min, respectively) in comparison to the LR60 group (89+-18 mg/dL and 140+-48 mL/min, respectively) and the LR80 group (75+-23 mg/dL and 153+-17 mL/min, respectively) (P=0.02 and P=0.026). In conclusion, fluid resuscitation during uncontrolled bleeding, to a target MAP of 60 mm Hg, using HES60 resulted in larger oxygen delivery and smaller systemic lactate A resuscitation to a target MAP of 60 or 80 mm Hg using LR.
Descriptors: blood and lymphatics, transport and circulation, cardiovascular system, transport and circulation, miscellaneous substances, hemorrhagic shock, vascular disease, therapy, fluid resuscitation, clinical techniques, therapeutic and prophylactic techniques, continuously bleeding, lactated ringer's solution, mean arterial blood pressure, six percent hydroxyethyl starch solution.
Gargiulo, N.J.3., F.J. Veith, T. Ohki, L.A. Scher, G.L. Berdejo, E.C. Lipsitz, M. Menegus, and M. Greenberg (2007). Histologic and duplex comparison of the perclose and angio-seal percutaneous closure devices. Vascular 15(1): 24-9. ISSN: 1708-5381.
Abstract: The intravascular and extravascular effects of percutaneous closure devices have not been well studied. We assessed the performance and healing characteristics in dogs of two devices approved by the US Food and Drug Administration. Nine adult male dogs were anesthesized prior to percutaneous access of both femoral arteries with a 6F sheath. All dogs were systemically heparinized to an activated clotting time (ACT) > 250 seconds. Duplex sonography was performed preoperatively to measure vessel diameter and flow velocity. In each dog, one of two devices (Perclose, Abbot Laboratories, Abbott Park, IL or Angio-Seal, St. Jude Medical, St. Paul, MN) was randomly deployed into one of the two femoral arteries. The other device was deployed on the opposite side. Duplex sonography was repeated immediately after deployment and 28 days later to measure changes in vessel diameter and flow velocity. At 28 days, angiography was performed on both femoral arteries before they were removed for histologic evaluation. The time required to excise each vessel reflected the degree of scarring. Hemostasis time for the Angio-Seal device far surpassed the Perclose device (39 +/- 7 vs 0 minutes; p < .05). Vessel narrowing was observed only at 28 days after deployment of the Angio-Seal device (p < .05). Extensive extravascular scarring was observed with the Angio-Seal device, which resulted in a longer femoral artery dissection time and greater periadventitial scar thickness compared with the Perclose device (p < .05). When compared with the Perclose suture closure device, the Angio-Seal collagen plug closure device prolonged hemostasis time and produced greater vessel narrowing and periadventitial inflammation (extravascular scarring) in a canine model at 4 weeks.
Descriptors: femoral artery surgery, hemostasis, surgical instrumentation, cicatrix pathology, dogs, femoral artery pathology, femoral artery ultrasonography, hemostasis, surgical methods, hyperplasia pathology, models, animal, time factors, ultrasonography, doppler, duplex methods, wound healing physiology.
Gunther, R., B. Driessen, F. Lurie, and J. Jahr (2003). Plasma hemoglobin contribution to oxygen consumption by a hemoglobin-based oxygen carriers in a canine hypovolemia model. FASEB Journal 17(4-5): Abstract No. 806.4. ISSN: 0892-6638.
NAL Call Number: QH301.F3
Descriptors: biochemistry and molecular biophysics, blood and lymphatics, transport and circulation, hypovolemia, blood and lymphatic disease, splenectomy, experimental surgical techniques, laboratory techniques, arterial partial oxygen pressure, venous partial oxygen pressure, arterial oxygen content, oxygen consumption, oxygen delivery, oxygen saturation, venous oxygen content.
Harding, T.C., K.E. Koprivnikar, G.H. Tu, N. Zayek, S. Lew, A. Subramanian, A. Sivakumaran, D. Frey, K. Ho, M.J. Vanroey, T.C. Nichols, D.A. Bellinger, S. Yendluri, J. Waugh, J. Mcarthur, G. Veres, and B.A. Donahue (2004). Intravenous administration of an aav-2 vector for the expression of factor ix in mice and a dog model of hemophilia b. Gene Therapy 11(2): 204-213. ISSN: 0969-7128.
Abstract: Previous experiments have demonstrated the stable expression of factor IX (FIX) protein in mice and canine models of hemophilia B following portal vein gene transfer with a recombinant adeno-associated virus (rAAV) vector encoding FIX. Here, we present the results of studies that further optimized the rAAV vector transgene cassette used to express FIX and explored the use of the less-invasive intravenous (i.v.) route of vector administration for the treatment of hemophilia B. First, a liver-specific promoter was evaluated in conjunction with cis-acting regulatory elements in mice. Constructs that included both the beta-globin intron and the woodchuck hepatitis virus post-transcriptional regulatory element resulted in the highest level of FIX expression in vivo. Using this optimized vector, we demonstrate that i.v. injection was feasible for hepatic gene transfer in mice, achieving 70-80% of portal vein expression levels of FIX. In further studies using the Chapel Hill strain of hemophilia B dogs, we demonstrate for the first time FIX expression and partial correction of the bleeding disorder following i.v. administration of an AAV vector.
Descriptors: blood and lymphatics, transport and circulation, cell biology, methods and techniques, molecular genetics, biochemistry and molecular biophysics, hemophilia B, blood and lymphatic disease, genetic disease, genetics, therapy, hepatic gene transfer, clinical techniques, intravenous vector administration, genetic techniques, portal vein gene transfer, clinical techniques, genetic techniques, laboratory techniques, therapeutic and prophylactic techniques.
Hayashi, K. (2003). Effects of angiotensin ii receptor antagonist on intestinal mucosal oxygenation during canine isovolemic hemodilution with hydroxyethyl starch. Japanese Journal of Anesthesiology 52(6): 603-610. ISSN: 0021-4892.
Abstract: Background: Although isovolemic hemodilution can be used clinically to reduce the need for blood transfusion, the critical hemoglobin level and severe indequacy of tissue oxygenation induced by hemodilution remain unknown. Methods: Anesthetized dogs were submitted to graded hemodilution (20% and 40% blood volume reductions of estimated circulating blood volume) replaced with 10% hydroxyethyl starch. The effect of angiotensin II receptor (AT-II) antagonist, candesartan, on the intestinal mucosal oxygenation was assessed by tonometric method. Results: The splanchnic blood flow, measured by transit-time flow meters, and intestinal mucosal oxygenation were maintained well during 20% blood volume reduction without AT-II antagonist. By severe blood volume reduction, however, inadequate oxygenation was observed without, but not with AT-II antagonist. Conclusions: These results suggest the protective effect of AT-II antagonist on intestinal perfusion during severe isovolemic hemodilution. Further investigation will be needed in patients undergoing major surgery with large anticipated blood loss.
Descriptors: blood and lymphatics, transport and circulation, pharmacology, isovolemic hemodilution, clinical techniques, therapeutic and prophylactic techniques.
Language of Text: Japanese.
Horwitz, M., K.F. Benson, Z. Duan, F.Q. Li, and R.E. Person (2004). Hereditary neutropenia: dogs explain human neutrophil elastase mutations. Trends in Molecular Medicine 10(4): 163-170 ISSN: 1471-4914.
NAL Call Number: QH506
Abstract: Mutations in ELA2 the gene encoding neutrophil elastase (NE), cause the human diseases cyclic neutropenia (CN) and severe congenital neutropenia (SCN). Numerous mutations are known, but their lack of consistent biochemical effect has proven puzzling. The recent finding that mutation of AP3B1, which encodes the P subunit of adaptor protein complex 3 (AP3), is the cause of canine CN suggests a model for the molecular basis of hereditary neutropenias, involving the mistrafficking of NE: AP3 recognizes NE as a cargo protein, and their interaction implies that NE is a transmembrane protein. Computerized algorithms predict two NE transmembrane domains. Most CN mutations fall within predicted transmembrane domains and lead to excessive deposition of NE in granules, whereas SCN mutations usually disrupt the AP3 recognition sequence, resulting in excessive transport to the plasma membrane.
Descriptors: molecular genetics, biochemistry and molecular biophysics, cyclic neutropenia, blood and lymphatic disease, genetics, hereditary neutropenia, blood and lymphatic disease, genetic disease, immune system disease, severe congenital neutropenia, computerized algorithm, mathematical and computer techniques, gene product interactions.
Jensen, T.B., O. Rahbek, S. Overgaard, and K. Soballe (2004). Platelet rich plasma and fresh frozen bone allograft as enhancement of implant fixation - an experimental study in dogs. Journal of Orthopaedic Research 22(3): 653-658. ISSN: 0736-0266.
Descriptors: blood and lymphatics, transport and circulation, skeletal system, movement and support, surgery, medical sciences, bone grafting, clinical techniques, therapeutic and prophylactic techniques, implant fixation, clinical techniques, titanium alloy implant, prosthetic, bone formation, enhancement, gap healing, enhancement.
Koide, M., S. Nishizawa, M. Yamaguchi, Y. Nonaka, and H. Namba (2004). Chronological changes of diameter, functional properties, and morphology of vasospastic artery in canine two-hemorrhage model. Journal of Pharmacological Sciences 94(Supplement 1): 94P. ISSN: 1347-8613.
Descriptors: biochemistry and molecular biophysics, cardiovascular system, transport and circulation, models and simulations, computational biology, hemorrhage, vascular disease, chronological changes, two hemorrhage model.
Lavergne, S.N. and L.A. Trepanier (2007). Anti-platelet antibodies in a natural animal model of sulphonamide-associated thrombocytopaenia. Platelets 18(8): 595-604. ISSN: 0953-7104.
Abstract: Delayed hypersensitivity (HS) reactions to sulphonamide antimicrobials occur in both humans and dogs with a similar clinical presentation, and may include thrombocytopaenia. Drug-dependent anti-platelet antibodies have been identified in humans with sulphonamide-associated thrombocytopaenia. Our purpose was to determine whether similar antibodies were present in dogs with sulphonamide-associated thrombocytopaenia. Flow cytometry was used to detect anti-platelet antibodies in sera from 32 dogs with sulphonamide HS, eight dogs that tolerated sulphonamide therapy without adverse reactions and nine healthy control dogs were used as controls. Anti-platelet antibodies were found more frequently, with significantly stronger fluorescence signals, in HS dogs (75%) compared to 'tolerant' dogs (38%), and in HS dogs with thrombocytopaenia (90%) compared to HS dogs with normal platelet counts (46%). Binding to platelets was enhanced in the presence of soluble sulphonamide in 42% of positive samples. Experiments with canine Glanzmann's platelets, and competition assays with fibrinogen fragments or anti-GP antibodies, did not support the hypothesis that these canine antibodies target the fibrinogen receptor. In conclusion, anti-platelet antibodies were identified in dogs with sulphonamide-associated thrombocytopaenia, which suggests a similar immunopathogenesis for this reaction in dogs as seen in humans. Further work in both species will determine whether these antibodies are pathogenic in vitro.
Descriptors: autoantibodies blood, blood platelets immunology, drug hypersensitivity, sulfonamides adverse effects, thrombocytopenia chemically induced, dogs, flow cytometry, models, animal, thrombocytopenia immunology.
Lee, R.S., C.S. Kuhr, G.E. Sale, E. Zellmer, W.J. Hogan, R. Storb, and M.T. Little (2003). Fty720 does not abrogate acute graft-versus-host disease in the dog leukocyte antigen-nonidentical unrelated canine model. Transplantation 76(8): 1155-1158. ISSN: 0041-1337.
NAL Call Number: QP89.T73
Abstract: Background. Acute graft-versus-host disease (GVHD) remains a significant impediment to successful hematopoietic stem-cell transplantation (HSCT). Here, we examined the effectiveness of 2-amino-2-(2-(4-octylphenyl)ethyl)-1,3-propanediol hydrochloride (FTY720), an immunosuppressant that retraffics activated lymphocytes to secondary lymphoid organs, for the treatment of acute GVHD in an established dog leukocyte antigen-nonidentical unrelated canine HSCT model. Methods. Dogs were given HSCT after conditioning with 920 cGy total body irradiation. The dogs received methotrexate 0.4 mg/kg/day on days 1, 3, 6, and 11 and FTY720 (5 mg/kg/day orally) after developing GVHD. Results. Five of six dogs achieved engraftment, developed acute GVHD, and were treated with FTY720. FTY720 resulted in a profound decrease in lymphocytes and a temporary mitigation of clinical GVHD; however, GVHD recurred in all dogs. Four of five dogs were euthanized because of severe GVHD and the fifth because of severe inanition associated with moderate GVHD. Conclusions. Compared with controls, treatment of GVHD with FTY720 did not control this complication or significantly increase survival.
Descriptors: blood and lymphatics, transport and circulation, methods and techniques, pharmacology, acute graft vs host disease, immune system disease, hematopoietic stem cell transplantation, laboratory techniques, dog leukocyte antigen nonidentical unrelated donor, engraftment.
Lesnikova, M., M.C. Jensen, A. Bukovsky, A. Nikitine, B. Thomasson, J. Morris, R.F. Storb, H.P. Kiem, R.A. Nash, and G.E. Georges (2003). Resistance to mycophenolate mofetil (mmf) after lentiviral transduction of canine t cells with a mutant impdh vector. Blood 102(11): 499B. ISSN: 0006-4971.
NAL Call Number: RB145.A1B57
Abstract: Several clinical studies of adoptive immunotherapy with genetically modified (GM) donor T cells infused after allogeneic hematopoietic cell transplantation (HCT) have shown limited in vivo function of the ex vivo expanded T cells. Multiple factors including duration of ex vivo cell culture, immunogenicity of the transgene, lack of a selective advantage for the GM T cells and insufficient preclinical data in large animal models may have impaired successful clinical translation of this approach. To help address these problems, we constructed a self-inactivating, replication incompetent lentiviral vector expressing a (Thr-333fwdarwIle, Ser-351fwdarwTyr) trans-dominant mutant inosine monophosphate dehydrogenase II (IMPDH*), which renders transduced T cells resistant to MMF with intact de novo guanosine synthesis. MMF administration after infusion of IMPDH* transduced T cells would inhibit host immune responses to the GM T cells and provide a proliferative advantage for transduced T cells. Lentiviral vector transduction can reduce the time in culture since T cell proliferation is not required. In preparation for in vivo studies in the dog model of allogeneic HCT, we first confirmed function of the IMPDH* vector in immortalized T cell lines and then optimized conditions for lentiviral transduciton of fresh, primary dog T cells to achieve 20-30% transduction efficiency. Replication incompetent, VSV-G pseudotyped IMPDH* lentiviral vector, pRRLsin.cPPT.MSCV.IMPDH*.Wpre, was prepared from transiently transfected 293T cells. Immortalized dog T lymphocyte CLGL-90 cells were transduced with IMPDH* lentiviral vector and selected in 1 muM MMF for 14 days. Transduced cells were cloned by limiting dilution and assayed for MMF resistance. All IMPDH* CLGL-90 clones were uniformly resistant to MMF 0.1 to 10 muM, compared to control CLGL cells. Quantitative TaqMan PCR assay with lentiviral-specific primers showed transduced CLGL clones had up to 3 lentiviral vector insertion copies per clone. Next, fresh CD3+ T cells were isolated from dog peripheral blood with immunomagnetic selection (Miltenyi) or plastic adherence to >90% purity. Cells were cultured with IL-2 (10 IU/mL) and IL-7 (20 ng/mL) for 72 hours. T cells were transduced once at an MOI of 20 with the spinoculation method. Transduced cells were stimulated after 24 hours with MHC-mismatched dendritic cells (DC) (10:1 responder: stimulator ratio) and selected in 0.5 muM MMF 2 days later. After 2nd stimulation with DCs, cells were assessed for proliferation with 3H-thymidine uptake. In the presence of MMF, IMPDH* transduced cells had 3-fold increased proliferation over nontransduced control T cells. In summary, lentiviral vector expressing trans-dominant mutant IMPDH* rendered transduced dog T cells resistant to MMF. These results establish the IMPDH* vector as a tool to confer in vivo resistance to MMF. We are planning adoptive immunotherapy studies with infusion of IMPDH* transduced donor T cells into recipient dogs treated with MMF after allogeneic HCT to determine the feasibility of in vivo selection of GM T cells.
Descriptors: blood and lymphatics, transport and circulation, immune system, chemical coordination and homeostasis, molecular genetics, biochemistry and molecular biophysics, pharmacology, adoptive immunotherapy, clinical techniques, immunologic techniques, laboratory techniques, therapeutic and prophylactic techniques, allogeneic hematopoietic cell transplantation, clinical techniques, lentivirus transduction, drug resistance mechanism, host immune response, transduction efficiency.
Letsou, G.V., E.M. Breznock, J. Whitehair, R.S. Kurtz, R. Jacobs, M.L. Leavitt, H. Sternberg, S. Shermer, S. Kehrer, J.M. Segall, M.A. Voelker, H.D. Waitz, and P.E. Segall (2003). Resuscitating hypothermic dogs after 2 hours of circulatory arrest below 6degreec. Journal of Trauma Injury Infection and Critical Care 54(5 Supplement): S177-S182. ISSN: 1079-6061.
Abstract: Background: Ultraprofound hypothermia may have a place in trauma rescue and resuscitation. We describe resuscitation of dogs after asanguineous perfusion and circulatory arrest of 2 hours at 2degree to 4degreeC. Methods: Nine dogs were cooled using a bypass apparatus and their circulating blood replaced with bicarbonated Hextend (Abbott, North Chicago, IL). Perfusion was continued to 2degree to 4degreeC, and 60 mL of 2 mol/L KCl and 20 mL of 50% MgSO4cntdot7H2O were infused intra-arterially, and circulation was arrested for 2 hours. The dogs were then rewarmed, transfused, defibrillated, weaned from by-pass, and allowed to awaken. Preoperative and postoperative biochemistry and hematology were compared. Results: Six dogs recovered fully. One of these dogs died of an infection 2 weeks later. Three other dogs never recovered because of technical or procedural difficulties. Biochemical and hematologic parameters were normal by 3 weeks. Conclusion: Hypothermic blood substitution with Hextend allows resuscitation after 2 hours of ice-cold circulatory arrest in dogs.
Descriptors: biochemistry and molecular biophysics, blood and lymphatics, transport and circulation, cardiovascular system, transport and circulation, methods and techniques, circulatory arrest, vascular disease, resuscitation, clinical techniques, therapeutic and prophylactic techniques, hypothermia.
Lurie, F., B. Driessen, J.S. Jahr, R. Reynoso, and R.A. Gunther (2003). Validity of arterial and mixed venous oxygen saturation measurements in a canine hemorrhage model after resuscitation with varying concentrations of hemoglobin-based oxygen carrier. Anesthesia and Analgesia 96(1): 46-50. ISSN: 0003-2999.
Abstract: In this study, we evaluated the validity of saturation measurements in mixed venous and arterial blood during posthemorrhagic anemia and resuscitation with varying levels of hemoglobin-based oxygen carrier (Hemoglobin glutamer-200 (bovine); Oxyglobin(R) (Hb-200)). Nineteen anesthetized, splenectomized, mixed-breed dogs were anesthetized (two were excluded from the data because they did not survive the exsanguination, supporting the validity of the model). Their pulmonary arteries were cannulated with the Abbott QVUE Oximetrix 3 catheter. An 18-gauge catheter was placed in the femoral artery, and a reusable Nellcor probe was applied to the tongue. Mixed venous and arterial samples were drawn at baseline, after 40% hemorrhage (to keep arterial pressure at 50 mm Hg), and postresuscitation with 30 mL/kg of 6% hetastarch in lactated Ringer's solution (n=4), 10 mL/kg of Hb-200, 20 mL/kg of hetastarch (n=6), 20 mL/kg of Hb-200, and 10 mL/kg of hetastarch (n=7). Samples were compared with oxygen content from the LEXO2CON-K oxygen analyzer, and oxygen content was calculated for all values from the monitors. Results were compared by using analysis of variance. There was good correlation (0.97gtoreqrgtoreq0.92) for the measured versus calculated hemoglobin oxygen saturation values at baseline. After resuscitation, the correlation between calculated and measured values of oxygen content was significantly smaller for all tested instruments. The values of oxygen content calculated from the oxygen saturation monitor and from the oximetric pulmonary artery can deviate by as much as 20% from directly measured values. We conclude that the administration of this oxygen therapeutic may interfere with the values of some monitors.
Descriptors: blood and lymphatics, transport and circulation, pharmacology, posthemorrhagic anemia, blood and lymphatic disease, resuscitation, clinical techniques, therapeutic and prophylactic techniques, oxygen saturation, arterial, mixed venous, validity .
Lurie, F., J.S. Jahr, B. Driessen, V. Bezdikian, and R.A. Gunther (2003). Measuring circulating blood volume using infused hemoglobin-based oxygen carrier (hboc, oxyglobin(r)) as an indicator: validation in a canine hypovolemia model. 2003 Annual Meeting of the American Society of Anesthesiologists, San Francisco, CA, USA; October 11-15, 2003, Abstract No. A 729,
Abstract: Direct determination of the circulating blood volume (CBV) is clinically desirable, especially when hemodynamic parameters such as blood pressure and heart rate are pharmacologically altered and may not be used with confidence for monitoring of CBV. In a rabbit model, we demonstrated that small volumes of HBOC may be used for measuring of CBV using the indicator-dilution technique (1). This study was aimed to validate this technique in a canine hypovolemia model with varying concentrations of infused HBOC. Methods: Twenty-four healthy mongrel dogs were anesthetized and anesthesia maintained with isoflurane in 21% oxygen and sufentanil infusion. All animals were mechanically ventilated. After splenectomy and insertion of arterial, venous, and balloon-tipped pulmonary arterial catheters, and recording of baseline values of total (HbTot) and plasma hemoglobin (HbPla), hematocrit (Hct), and major hemodynamic parameters, dogs were bled (average 36.6 +- 5.8 mL/kg) to a mean arterial pressure of 50 mmHg and maintained hypovolemic for 1 h. Thereafter, measurements were repeated and dogs were resuscitated. Animals in Group 1 were resuscitated with 30 mL/kg of 6 % hetastarch solution (HES; Hextend(R), Abbott, Chicago, Il). Animals in other groups received either 10 mL/kg of hemoglobin glutamer-200 (Hb-200; Oxyglobin(R), Biopure, Cambridge, MA) plus 20 mL/kg HES (Group 2), 20 mL/kg Hb-200 plus 10 mL/kg HES (Group 3), or 30 mL/kg Hb-200 (Group 4). Solutions were infused at 30 mL/kg/h. Measurements were repeated immediately after volume resuscitation. Plasma Hb (HbPla) concentration was determined after centrifugation using the HemoCue(R) (Angelholm, Sweden). Lactated Ringer's solution was infused in all subjects at 5mL/kg/hour for maintenance. CBV at baseline was estimated as 85 mL/kg. CBV values immediately post hemorrhage were calculated by subtracting the volume of withdrawn blood from the baseline value. Based on the assumption that hemorrhage and subsequent volume resuscitation would not cause any hemolysis (as confirmed in group 1), all HbPla was considered to represent infused HBOC. The calculation of CBV using HBOC as an indicator was performed as previously published (1). CBV values derived from measured HBOC concentrations in plasma were compared to calculated (based on an original CBV of 85 mL/kg and withdrawn blood volume) values of CBV utilizing the Bland-Altman analysis, and by linear correlation. Agreement between the methods was analyzed by calculating the bias estimated by the mean difference and the standard deviation of the difference. Results: Calculated and measured CBV values were highly correlated (r=0.97). The difference between indicator dilution-derived and calculated values of CBV did not exceed 4% of calculated CBV in 97% of the measurements. The mean difference between measured and calculated values of CBV was 72 +/- 16 mL, and did not vary significantly between groups 2, 3, and 4 (at varying concentrations of HBOC infused). Conclusions: In a canine hypovolemia model, knowing both the HBOC volume infused and the HBOC concentration measured in plasma allows for reliably determining the circulating blood volume. Our data validate the indicator-dilution technique with HBOC as an appropriate and clinically valuable method for monitoring CBV in treatment of hypovolemia..
Descriptors: blood and lymphatics, transport and circulation, cardiovascular system, transport and circulation, pharmacology, hemorrhage, vascular disease, drug therapy, bland altman analysis, mathematical and computer techniques, centrifugation, laboratory techniques, linear correlation, mathematical and computer techniques, blood pressure, heart rate, hematocrit, hemodynamic parameters, hemolysis, hypovolemia, mean circulating blood volume.
Maalaej, N. and J.D. Folts (1996). Increased shear stress overcomes the antithrombotic platelet inhibitory effect of aspirin in stenosed dog coronary arteries. Circulation 93(6): 1201-1205. ISSN: 0009-7322.
NAL Call Number: RC681.A1 C8
Abstract: Background: Shear stress is one of the known platelet activating mechanisms that leads to thrombosis. Increased shear stress has also been postulated to reverse the antithrombotic effect of some drugs such as aspirin (ASA). Methods and Results: Experiments were conducted in five dogs to determine the minimal shear stress levels that produce acute platelet thrombus formation in mechanically stenosed arteries and the increase in shear required to reverse the antithrombotic effect of ASA. After intimal and medial damage, stenosis was produced in the circumflex coronary artery. We used the finite-difference numerical solution of the Navier-Stokes equation to determine the wall shear stresses in the area of stenosis. At 70 +- 6% coronary diameter reduction, cyclic flow reductions (CFRs) caused by acute platelet thrombus formation were observed in the stenosed lumen. At this level of stenosis, the shear stress was 144 +- 15 Pa. ASA given at a dose of 5 mg/kg IV inhibited in vivo acute platelet-mediated thrombus formation and abolished CFRs in all dogs. However, increasing the stenosis level to 80 +- 5% caused the CFRs to return. The shear stress increased with the increased level of stenosis to 226 +- 22 Pa. Thus, an average 10% increase in diameter narrowing caused a 56 +- 20% increase in shear stress (P lt .005) and renewed platelet activation and thrombus formation despite ASA pretreatment. Conclusions: Individuals who take ASA daily to prevent coronary artery thrombus formation may not be well protected when a change in hemodynamics, such as an acute hypertensive episode, or an increase in stenosis severity due to a ruptured atherosclerotic plaque causes an increase in shear stress.
Descriptors: blood and lymphatics, transport and circulation, cardiovascular system, transport and circulation, pharmacology, anticoagulant drug, aspirin, thrombosis.
Miao, C.H., H. Jiang, and B. Sun (1997). Inhaled nitric oxide improves ventilation efficiency and hemodynamic properties in dogs with endotoxin induced acute respiratory distress syndrome. Pediatric Research 41(4 PART 2): 36A ISSN: 0031-3998.
NAL Call Number: RJ1.P4
Descriptors: blood and lymphatics, transport and circulation, cardiovascular system, transport and circulation, pharmacology, respiratory system, respiration, toxicology, cardiovascular drug, critical care, endotoxin induced acute respiratory distress syndrome, gas exchange, hemodynamic properties, inhaled administration efficacy, nitric oxide, pharmacodynamics, pharmacokinetics, pharmacology, respiratory system, respiratory system disease, ventilation efficiency.
Mink, S.N., H. Jacobs, K. Duke, D. Bose, Z.Q. Cheng, and R.B. Light (2004). N,N',N"-triacetylglucosamine, an inhibitor of lysozyme, prevents myocardial depression in Escherichia coli sepsis in dogs. Critical Care Medicine. 32(1): 184-93. ISSN: 0090-3493.
Abstract: OBJECTIVE: Reversible myocardial depression in sepsis has been ascribed to the release of inflammatory mediators. We recently found that lysozyme c (Lzm-S), consistent with that originating from the spleen, was a mediator of myocardial depression in an Escherichia coli model of septic shock in dogs. We further showed in a right ventricular trabecular (RVT) preparation that Lzm-S's depressant activity could be blocked by N,N',N" triacetylglucosamine (TAC), a competitive inhibitor of Lzm-S. We hypothesized that Lzm-S binds to or cleaves a cardiac membrane glycoprotein, thereby interfering with myocardial contraction in sepsis. In the present study, we examined whether TAC could prevent myocardial depression in an in vivo preparation and whether other related N-acetylglucosamine (NAG) structures could also inhibit Lzm-S's effect in RVT. DESIGN: Randomized experimental study. SETTING: University laboratory. SUBJECTS: Anesthetized, mechanically ventilated dogs. INTERVENTIONS: We produced sepsis by infusion of E. coli over an approximately 6-hr period. MEASUREMENTS AND MAIN RESULTS: We examined the effect of TAC on stroke work, our primary index of myocardial function, when treatment was administered before sepsis (pretreatment) and after 1.5 hrs (early treatment study) and 3.5 hrs of sepsis (late treatment study; LTS). In the pretreatment study and early treatment study, myocardial depression would have not yet occurred but would have already been present in the late treatment study. In RVT, we assessed the effect of other NAG oligosaccharides and variants to the NAG structure on Lzm-S's depressant activity. In pretreatment and the early treatment study, TAC prevented the reduction in stroke work observed in nontreated septic groups but did not reverse the reduction found in the late treatment study. In RVT, of the compounds tested, only N,N'-diacetylglucosamine showed an inhibitory effect. CONCLUSIONS: We found that TAC, a competitive inhibitor of Lzm-S, prevented myocardial depression in experimental sepsis. Only specific NAG structures are inhibitory to Lzm-S's depressant activity. TAC may be useful in attenuating cardiovascular collapse in sepsis.
Descriptors: animal model, Escherichia coli, sepsis, septic shock model, anesthetized, mechanically ventilated, sepsis, cardiovascular collapse.
Minneci, P.C., K.J. Deans, S. Shiva, H. Zhi, S.M. Banks, S. Kern, C. Natanson, S.B. Solomon, and M.T. Gladwin (2008). Nitrite reductase activity of hemoglobin as a systemic nitric oxide generator mechanism to detoxify plasma hemoglobin produced during hemolysis. American Journal of Physiology. Heart and Circulatory Physiology 295(2): H743-54. ISSN: 0363-6135.
NAL Call Number: 447.8 Am3
Abstract: Hemoglobin (Hb) potently inactivates the nitric oxide (NO) radical via a dioxygenation reaction forming nitrate (NO(3)(-)). This inactivation produces endothelial dysfunction during hemolytic conditions and may contribute to the vascular complications of Hb-based blood substitutes. Hb also functions as a nitrite (NO(2)(-)) reductase, converting nitrite into NO as it deoxygenates. We hypothesized that during intravascular hemolysis, nitrite infusions would limit the vasoconstrictive properties of plasma Hb. In a canine model of low- and high-intensity hypotonic intravascular hemolysis, we characterized hemodynamic responses to nitrite infusions. Hemolysis increased systemic and pulmonary arterial pressures and systemic vascular resistance. Hemolysis also inhibited NO-dependent pulmonary and systemic vasodilation by the NO donor sodium nitroprusside. Compared with nitroprusside, nitrite demonstrated unique effects by not only inhibiting hemolysis-associated vasoconstriction but also by potentiating vasodilation at plasma Hb concentrations of <25 muM. We also observed an interaction between plasma Hb levels and nitrite to augment nitroprusside-induced vasodilation of the pulmonary and systemic circulation. This nitrite reductase activity of Hb in vivo was recapitulated in vitro using a mitochondrial NO sensor system. Nitrite infusions may promote NO generation from Hb while maintaining oxygen delivery; this effect could be harnessed to treat hemolytic conditions and to detoxify Hb-based blood substitutes.
Descriptors: blood substitutes toxicity, hemodynamics drug effects, hemoglobins metabolism, hemolysis drug effects, nitric oxide metabolism, nitrite reductases blood, sodium nitrite pharmacology, vasodilator agents pharmacology, biosensing techniques, blood pressure drug effects, dogs, dose response relationship, drug, infusions, intravenous, mitochondria, liver drug effects, mitochondria, liver enzymology, models, animal, nitroprusside pharmacology, rats, rats, sprague dawley, sodium nitrite administration and dosage, sodium nitrite pharmacokinetics, time factors, vascular resistance drug effects, vasoconstriction drug effects, vasodilation drug effects, vasodilator agents administration and dosage, vasodilator agents pharmacokinetics.
Mitaka, C., Y. Hirata, K. Yokoyama, K. Makita, and T. Imai (2001). A selective inhibitor for inducible nitric oxide synthase improves hypotension and lactic acidosis in canine endotoxic shock. Critical Care Medicine. 29(11): 2156-61. ISSN: 0090-3493.
Abstract: OBJECTIVE: To investigate whether ONO-1714, a putative selective inhibitor for inducible nitric oxide synthase, modulates systemic hemodynamics, arterial blood gases, lactate concentrations, gastric mucosal perfusion, and renal and hepatic functions in endotoxic shock. DESIGN: Prospective, randomized, controlled animal study. SETTING: Laboratory at a university hospital. SUBJECTS: Eighteen male beagle dogs (12-19 kg) under pentobarbital anesthesia. INTERVENTIONS: Dogs were mechanically ventilated and monitored with a pulmonary arterial catheter and a gastric tonometer. They were divided in three groups: a) lipopolysaccharide (LPS) plus vehicle group (n = 6), which received LPS (250 ng/kg/min for 2 hrs) and saline 1 hr later; b) LPS plus ONO (0.05) group (n = 6), which received ONO-1714 (0.05 mg/kg) 1 hr after the start of LPS; c) LPS plus ONO (0.1) group (n = 6), which received ONO-1714 (0.1 mg/kg) 1 hr after the start of LPS. MEASUREMENTS AND MAIN RESULTS: Hemodynamics, blood gas parameters, gastric intramural pH, urine output, and serum levels of lactate, transaminases, bilirubin, and creatinine were measured during a 6-hr observation period. LPS induced hypotension, lactic acidosis, gastric mucosal acidosis, and renal and hepatic dysfunction. ONO-1714 reversed the LPS-induced hypotension and lactic acidosis without deteriorating cardiac output, oxygen delivery, or gastric mucosal acidosis. CONCLUSIONS: These findings suggest that ONO-1714 is a useful agent to reverse hypotension and lactic acidosis in a canine endotoxic shock model.
Descriptors: animal model, endotoxic shock, ONO-1714, selective inhibitor, nitric oxide synthase, hemodynamics.
Obra, R., E.J. Harper, and J. Lunec (1999). Exercise in healthy adult dogs increases plasma tbars-an indicator of oxidative stress. FASEB Journal 13(4 Part 1): A565. ISSN: 0892-6638.
NAL Call Number: QH301.F3
Descriptors: biochemistry and molecular biophysics, physiology, hplc, high performance liquid chromatography, measurement method, exercise, oxidative stress, exercise induced, meeting abstract.
Ovlisen, K., A.T. Kristensen, and M. Tranholm (2008). In vivo models of haemophilia - status on current knowledge of clinical phenotypes and therapeutic interventions. Haemophilia the Official Journal of the World Federation of Hemophilia 14(2): 248-59.
Abstract: Animal models have contributed immensely to the understanding of and the improvement in treatment of haemophilia A and B. First, establishment of haemophilic dog colonies provided an invaluable opportunity to investigate the diseases and later, the advances in gene technologies resulting in small haemophilic animal models were a milestone in the preclinical research making it possible to address some of the many unanswered questions. This review provides an overview of animal models used in the study of haemophilia as well as a short overview of the contributions resulting from studies in these models.
Descriptors: hemophilia a drug therapy, hemophilia a genetics, models, animal, breeding, disease models, animal, dogs, genetic engineering, hemostatics therapeutic use, mice, mice, transgenic, rabbits.
Raife, T., K.D. Friedman, and B. Fenwick (2004). Lepirudin prevents lethal effects of shiga toxin in a canine model. Thrombosis and Haemostasis 92(2): 387-393. ISSN: 0340-6245.
Abstract: Microvascular thrombosis is a major cause of organ damage in Shiga toxin-mediated hemolytic uremic syndrome (Stx-HUS). In vitro and clinical studies implicate thrombin-mediated mechanisms in the pathogenesis of Stx microvascular thrombosis. In a greyhound model, administration of 0.03 mug/kg to 0.05mug/kg Stx1 or Stx2 causes severe bloody diarrhea and HUS with microvascular thrombosis requiring humane euthanasia within 65 hours. Using a greyhound model of Stx-HUS we analyzed early hemostatic changes, and tested the hypothesis that thrombin blockade with lepirudin would prevent lethal Stx effects. Two Stx1-exposed greyhounds were analyzed for hemostatic changes prior to onset of clinical manifestations. Serial hemostasis studies after Stx1 challenge revealed trends of increased aPTT, fibrinogen levels, and prothrombin fragment 1+2, and appearance of abnormally large von Willebrand factor multimers. Three greyhounds were anticoagulated with lepirudin to maintain activated partial thromboplastin times (aPTT) >2.5-fold normal, followed by administration of Stx2 and observation of clinical responses. Among the 3 lepirudin-treated, Stx2-challenged greyhounds, one developed severe illness requiring euthanasia. Remarkably, 2 of the 3 greyhounds developed only hypersalivation and restlessness that resolved (P <.03 compared to 14 historical controls). These two greyhounds were clinically, hematologically and biochemically normal 74 hours after Stx administration, well beyond the time of euthanasia of any previous greyhound. This study suggests that greyhounds exposed to Stx develop procagulant changes similar to humans, and that thrombin may be a critical factor in the pathogenesis and treatment of Stx-HUS.
Descriptors: blood and lymphatics, transport and circulation, cardiovascular system, transport and circulation, pharmacology, toxicology, Shiga toxin mediated hemolytic uremic syndrome, blood and lymphatic disease, infectious disease, urologic disease, chemically induced, microvascular thrombosis, vascular disease, hemostasis .
Shaw, M., R. Moutvic, M. Brooker, and I. Grossi (2003). Evaluation of the effects of intermittent exposure to elevated inhaled co2 concentrations upon blood gas and hematologic parameters in the canine. Toxicological Sciences 72(S-1): 296 ISSN: 1096-6080.
NAL Call Number: RA1190.F8
Descriptors: biochemistry and molecular biophysics, blood and lymphatics, transport and circulation, respiratory system, respiration, hematocrit, laboratory techniques, hematologic parameters, minute volume, peak inspiratory flow, tidal volume.
Skripchenko, A., A. Balch, A. Mackin, and S.J. Wagner (2007). In vivo recovery and survival of red cells after photodynamic treatment with thiopyrylium and red light using a canine model. Vox Sanguinis 92(2): 157-9. ISSN: 0042-9007.
NAL Call Number: 448.8 V94
Abstract: Recently, we have shown that thiopyrylium has robust inactivation capabilities against a broad spectrum of pathogens in the human red blood cell (RBC) suspensions while retaining key RBC in vitro properties. The 24-h recovery and survival of canine red cells were measured upon autologus reinfusion of control and phototreated units. The 24-h recovery of control and phototreated RBCs was 75.7 +/- 6.4% and 87.5 +/- 8.5%, respectively. The time for 50% survival of labelled control RBCs was similar to that of phototreated group (206 +/- 58 h vs. 255 +/- 63 h, respectively). Results suggest that thiopyrylium phototreatment does not negatively affect canine RBC in vivo recovery.
Descriptors: aniline compounds pharmacology, blood preservation methods, erythrocytes drug effects, hemolysis drug effects, photosensitizing agents pharmacology, pyrans pharmacology, bacterial infections prevention and control, cell survival, decontamination methods, dogs, erythrocyte membrane drug effects, erythrocytes microbiology, erythrocytes virology, models, animal, virus diseases prevention and control.
Stokol, T. (2003). Plasma D-dimer for the diagnosis of thromboembolic disorders in dogs. Veterinary Clinics of North America. Small Animal Practice 33(6): 1419-35. ISSN: 0195-5616.
NAL Call Number: SF601.V523
Abstract: D-dimer is formed during thrombus formation when factor XIIIa crosslinks the terminal D-domains of fibrin. The D-dimer epitope is exposed when the thrombus is lysed by plasmin. Thus, D-dimer represents both thrombin and plasmin activation and is specific for fibrinolysis. D-dimer concentrations are increased in dogs with DIC or other thromboembolic disorders, but because D-dimer is an indicator of physiologic or pathologic fibrinolysis, values are elevated in other conditions associated with fibrinolysis, including orthopedic surgery, neoplasia, and internal hemorrhage. It can be used as an ancillary test for the diagnosis of DIC but is not recommended as a sole test for this purpose. D-dimer has the potential to be a useful laboratory test for the detection of pulmonary thromboembolism in dogs. Further studies are needed to determine the appropriate applications for this test in veterinary patients to aid in clinical decision making, treatment, and patient care.
Descriptors: D-dimer, thrombus formation, plasmin activation, thromboembolic disorders, orthopedic surgery, neoplasia, internal hemorrhage.
Tisherman, S.A. (2004). Suspended animation for resuscitation from exsanguinating hemorrhage. Critical Care Medicine 32(2 Suppl): S46-50. ISSN: 0090-3493.
Abstract: In dogs, isotonic saline at 0-4 degrees C, flushed into the aorta at a rate of 1-2 L/min, with drainage of the vena cava, can achieve deep to profound hypothermia of vital organs at a cooling rate of up to 3 degrees C per minute. This achieves preservation of viability of the organism during predictable durations of no flow: cardiac arrest of 15-20 mins at Tty of 30-35 degrees C, cardiac arrest of 30 mins at Tty of 25 degrees C, cardiac arrest of 60 mins at Tty of 15 degrees C, and cardiac arrest of 90 mins at Tty of 10 degrees C. So far, pharmacologic approaches have not resulted in any breakthrough effect on outcome above that achieved with hypothermia, except perhaps the antioxidant tempol. Additional studies of novel drugs and, perhaps, combination therapies remain warranted. The optimal fluids to have in the circulation during circulatory arrest and reperfusions need to be determined. As laboratory studies to optimize suspended animation proceed, clinical trials should be initiated. In addition, devices should be developed to facilitate induction of suspended animation, eventually in the field.
Descriptors: animal model, hypothermia, vital organs, circulatory arrest, suspended animation.
Varicoda, E.Y., L.F. Poli De Figueiredo, R.J.J. Cruz, L.E. Silva, and M. Rocha E Silva (2003). Blood loss after fluid resuscitation with isotonic or hypertonic saline for the initial treatment of uncontrolled hemorrhage induced by spleen rupture. Journal of Trauma Injury Infection and Critical Care 55(1): 112-117. ISSN: 1079-6061.
Abstract: Background: It has been suggested that fluid resuscitation for the prehospital management of hypotensive trauma victims increases bleeding. In a model of uncontrolled hemorrhage induced by complete splenic laceration with a hilar vascular injury, we hypothesized that small-volume hypertonic saline or large-volume lactated Ringer's solution may provide sustained hemodynamic benefits despite promoting increases in intra-abdominal bleeding. Methods: Forty anesthetized, spontaneously breathing dogs (18 +- 1 kg) underwent laparotomy. A suture line was placed around the spleen to produce a splenic rupture with hilar vascular injury by pulling the exteriorized lines after incision closure. Intra-abdominal blood loss was measured directly, immediately after the animal was killed. Dogs were randomly assigned to four groups (n = 10 per group): Untreated controls were killed 20 (CT20) or 40 (CT40) minutes after splenic rupture to measure blood loss directly. Treatment groups received (20 minutes after spleen rupture) lactated Ringer's (LR), 33 mL/kg over 15 minutes, or 7.5% NaCl/6% dextran 70 (HSD), 4 mL/kg over 4 minutes. Blood loss was measured 40 minutes after spleen rupture. Results: Mean arterial pressure dropped from an average value of 103 +- 3 mm Hg to 67 +- 5 mm Hg during the first 20 minutes and was partially restored afterward in all groups, with no significant differences between them. No resuscitation was associated with low cardiac output, whereas HSD restored and LR overshot baseline cardiac output. Intraabdominal blood loss was 30 +- 4, 38 +- 4, 43 +- 5, and 42 +- 5 mL/kg for groups CT20, CT40, HSD, and LR, respectively, with no statistical significance between groups. Conclusion: No-fluid resuscitation in uncontrolled hemorrhage from splenic rupture resulted in a low-flow state, whereas resuscitation with small volumes of HSD or large volumes of LR produced hemodynamic benefits without significant increases in bleeding.
Descriptors: biochemistry and molecular biophysics, blood and lymphatics, transport and circulation, cardiovascular system, methods and techniques, hemorrhage, ascular disease, spleen rupture, blood and lymphatic disease, injury, fluid resuscitation, clinical techniques, therapeutic and prophylactic techniques.
Wu, M.H.D., Y. Kouchi, Y. Onuki, Q. Shi, H. Yoshida, S. Kaplan, R.F. Viggers, R. Ghali, and L.R. Sauvage (1995). Effect of differential shear stress on platelet aggregation, surface thrombosis, and endothelialization of bilateral carotid-femoral grafts in the dog. Journal of Vascular Surgery 22(4): 382-392. ISSN: 0741-5214.
Abstract: Purpose: The purpose of this study was to determine the effects of increased shear stress on the aggregability of platelets as they traverse a long, small-caliber (6 min) Dacron graft in the dog and on the surface thrombosis and endothelialization of such a graft. Methods: Each of nine dogs received bilateral carotid-femoral artery grafts, approximately 75 cm long, for 3 months; one graft of each pair had a distal femoral arteriovenous fistula to produce a higher shear rate than the contralateral graft. Platelet aggregation scores were determined on blood withdrawn from the external jugular vein and eta-m the proximal and distal ends of the grafts in each animal. Graft flow rates, which were used in the computation of shear stress, and luminal pressure gradients through grafts were measured during surgery and specimen retrieval. Specimens were studied with light microscopy after hematoxylin and eosin and immunocytochemical staining and by scanning electron and transmission electron microscopy to evaluate the nature, composition, and thickness of the flow surface lining, as well as the transmural healing. Results: Two high-shear stress and two low-shear stress grafts occluded unilaterally; five dogs had bilaterally patent grafts, allowing comparative analyses. AR subjects had low platelet aggregability with aspirin. Platelet aggregation scores taken from proximal and distal ends of the grafts were not significantly different. The high-shear stress grafts had significantly more endothelial-like cell coverage (p lt 0.0371) than the low-shear stress grafts, less flow-surface thrombus (p lt 0.0056), and a thinner surface lining (p lt 0.0029), on both the neointima and pseudointima. Conclusions: In subjects with low platelet aggregation scores, long Dacron grafts do not elevate platelet aggregability of blood flowing through them. High-shear stress grafts have less flow surface thrombus, more endothelialization, and a thinner surface lining than do low-shear stress grafts.
Descriptors: blood and lymphatics, transport and circulation, cardiovascular system, transport and circulation, cell biology, methods and techniques, morphology, physiology, axillofemoral bypass, dacron graft, graft patency, intimal hyperplasia, surgical method.
Yu, S., Y. Ma, T. Xia, and S. Ma (1995). Studies of action of rhodobrun roseum limpr on changes of red cell aggregation and yield-shear stress in dogs with acute experimental coronary occlusion. Zhongguo Zhongyao Zazhi 20(7): 429-431, 449. ISSN: 1001-5302.
Abstract: Following acute occlusion of the left anterior descending coronary artery in dogs, significant increases were observed in the red cell aggregation index, yield-shear stress and red cell electrophoretic time in blood drained from ischemic area. When transfusion was performed with Rhodobrum roseum solution from the right femoral vein, significant rises of the above-said items were observed.
Descriptors: biochemistry and molecular biophysics, blood and lymphatics, transport and circulation, cardiovascular system, transport and circulation, cell biology, pharmacognosy, pharmacology, blood viscosity, myocardial ischemia.
Language of Text: Chinese.
Zaucha, J.M., C. Yu, G. Mathioudakis, K. Seidel, G. Georges, G. Sale, M.T. Little, B. Torok Storb, and R. Storb (2001). Hematopoietic responses to stress conditions in young dogs compared with elderly dogs. Blood 98(2): 322-327. ISSN: 0006-4971.
NAL Call Number: RB145.A1B57
Abstract: Clinical observations show that older patients do not tolerate high-dose chemoradiotherapy as well as younger patients. It is unclear whether this is due to age-related differences in their responses to hematopoietic injury or to differential toxicities to other organs. In the present study, 6 young (0.5 years) and 6 elderly (8 years) dogs were challenged with 7 repeated nonlethal doses of 50 or 100 cGy total body irradiation (TBI) each (total 550 cGy), and 21 days of recombinant canine granulocyte-colony stimulating factor (rcG-CSF) after the last TBI dose. Recoveries of absolute neutrophil, platelet, and lymphocyte counts after each TBI dose, responses to rcG-CSF treatment, and telomere lengths in neutrophils were compared before and after the study. No differences were found in recoveries of neutrophils, platelets, or in responses to rcG-CSF among young and old dogs. In contrast, recoveries were suggestively worse in younger dogs. After rcG-CSF, platelet recoveries were poor in both groups compared with previous platelet recoveries (P<.01). Consequently, 2 old and 3 young dogs were euthanized because of persistent thrombocytopenia and bleeding. At the study's completion, marrow cellularities and peripheral blood counts of the remaining young and elderly dogs were equivalent. The telomere lengths in both groups were significantly reduced after the study versus beforehand (P=.03), but the median attritions of telomeres were not different. It was concluded that aging does not appear to affect hematopoietic cell recoveries after repeated low-dose TBI, suggesting that poor tolerance of radiochemotherapy regimens in older patients may be due to nonhematopoietic organ toxicities rather than age-related changes in hematopoietic stem cells reserves.
Descriptors: aging, pharmacology, radiation biology, blood and lymphatics, transport and circulation, thrombocytopenia, blood and lymphatic disease, radiochemotherapy, radiologic method, therapeutic method, bleeding, hematopoietic responses, stress conditions, total body irradiation.
Zhang, H., R. De Jongh, D. De Backer, S. Cherkaoui, B. Vray, and J.L. Vincent (2001). Effects of alpha - and beta -adrenergic stimulation on hepatosplanchnic perfusion and oxygen extraction in endotoxic shock. Critical Care Medicine. 29(3): 581-8. ISSN: 0090-3493.
Abstract: OBJECTIVE: To examine the effects of adrenergic stimulation on hepatosplanchnic perfusion, oxygen extraction, and tumor necrosis factor-alpha production during endotoxic shock. DESIGN: In vivo, prospective, randomized, controlled, repeated-measures, experimental study. SETTING: Experimental physiology laboratory in a university teaching hospital. SUBJECTS: Twenty-one anesthetized and mechanically ventilated dogs. INTERVENTIONS: An intrapericardial catheter was positioned. Catheters for blood sampling were inserted into the right femoral artery, hepatic vein, portal vein, and pulmonary artery. Ultrasonic flow probes were placed around the portal vein, the hepatic artery, the mesenteric artery, the left renal artery, and the left femoral artery. Animals received 2 mg/kg of Escherichia coli endotoxin, followed by fluid resuscitation. Seven dogs received intravenous isoproterenol (0.1 microg/kg x min(-1)), seven received phenylephrine (1 microg/kg x min(-1)), and seven served as controls. Thirty minutes later, cardiac tamponade was introduced to study organ perfusion and tissue oxygen extraction capabilities. MAIN RESULTS: The isoproterenol group had a higher cardiac index and stroke index and lower systemic vascular resistance than the other groups. The phenylephrine group had a higher arterial pressure but a lower cardiac index than the isoproterenol group. The isoproterenol group had a higher hepatic artery blood flow than the other groups and a higher portal and mesenteric flow than the control group. Liver and gut mucosal blood flow was greater in the isoproterenol than in the phenylephrine group. The isoproterenol group had a lower global critical oxygen delivery than the other groups (8.8 +/- 1.3 vs. 13.1 +/- 2.0 (control) and 11.8 +/- 3.3 mL/kg x min(-1) (phenylephrine); both p < .05) and a higher liver critical oxygen extraction ratio than the control group. Isoproterenol tended to attenuate, but phenylephrine significantly increased, blood tumor necrosis factor levels. CONCLUSIONS: During endotoxic shock, beta-stimulation can improve hepatosplanchnic perfusion and enhance tissue oxygen extraction capabilities, whereas alpha-stimulation does not. In addition, alpha-adrenergic stimulation can increase tumor necrosis factor levels.
Descriptors: endotoxic shock model, adrenergic stimulation, hepatosplanchnic perfusion, oxygen extraction, tumor necrosis factor-alpha production.
Zhang, X.B., T. Neff, R.K. Humphries, and H.P. Kiem (2003). Retroviral overexpression of human hoxb4 confers an ex vivo growth advantage to cd34+ cells from dogs, baboons, macaques and humans. Blood 102(11): 569A. ISSN: 0006-4971.
NAL Call Number: RB145.A1B57
Abstract: Over-expression of the human HoxB4 gene has been shown to induce ex vivo expansion and self-renewal of murine long term repopulating multilineage hematopoietic stem cells. Successful ex vivo expansion of stem cells has great potential for clinical cell therapy applications. Since mouse and human differ substantially with respect to stem cell biology, we have started to develop a large animal model to study the effect of HoxB4 on hematopoietic stem cells in a clinically more relevant experimental setup. We investigated if human HoxB4 enhances in vitro expansion of CD34+ cells from mobilized dog peripheral blood (PB), cytokine primed baboon and macaque bone marrow (BM), human cord blood (CB) and mobilized human PB. Baboon, macaque and human cells were cultured in IMDM/10%FCS in the presence of human TPO, SCF, Flt3-L, IL-6, IL-3 and G-CSF each at 100 ng/ml. Dog cells were cultured in human Dexter media with Flt3-L, canine SCF and canine G-CSF, each at 50 ng/ml. Enriched CD34+ cells were pre-stimulated for 2 days and then transduced twice with Phoenix-GALV or RD114 pseudotyped MSCV-HoxB4-ires-GFP or the control vector, MSCV-ires-YFP. Cells were maintained in suspension cultures. Cultures were split every week, and flow-cytometric analysis for GFP/YFP-expression and CFU assays were performed. After 4 weeks culture, the percentage of HoxB4-overexpressing dog cells increased from 30% to 76% (n=5), while YFP (mock)-transduced dog cells decreased from 53% to 30% (n=5) (p<0.05, paired T test). The same HoxB4-mediated growth advantage was observed for baboon (GFP from 29% to 63% and YFP from 33% to 26%)(n=4) (p<0.05) and macaque (GFP from 32% to 80% and YFP from 38% to 43%)(n=4) (p<0.05). In dog, macaque and baboon cells, HoxB4-overexpression resulted in an up to 28-fold expansion of CFUs compared with YFP-transduced control cells. Transduction with the HoxB4-vector also augmented total cell expansion 3 to 5-fold in suspension cultures of dog, baboon and macaque cells when compared with YFP-transduced controls (p<0.05). In human CB, HoxB4 overexpression induced a 2-fold augmented expansion in the number of CFUs relative to YFP control. Of note, flow cytometric analysis of liquid cultures did not show a difference in human cord blood cells (GFP from 81% to 53% and YFP from 93% to 56%) (n=3). In preliminary experiments we were unable to demonstrate a HoxB4 mediated in vitro growth advantage in human PB CD34+ cells. In conclusion, our data demonstrate that HoxB4 has an effect on CD34+ cells from dog, macaque and baboon. The effect on human PB cells is less pronounced than that on human CB cells. Our data indicate that either of the two non-human primates or the canine model can be used to investigate the effects of HoxB4 on hematopoietic stem cells in a clinically relevant model.
Descriptors: blood and lymphatics, transport and circulation, molecular genetics, biochemistry and molecular biophysics.