bluuebunny/crossref_metadata_2025 huggingface dataset:
The pancreatic islet β-cell-enriched transcription factor Pdx-1 regulates Slc30a8 gene transcription through an intronic enhancer
Authors: Pound Lynley D. , Hang Yan , Sarkar Suparna A. , Wang Yingda , Milam Laurel A. , Oeser James K. , Printz Richard L. , Lee Catherine E. , Stein Roland , Hutton John C. , O'Brien Richard M.
Published: October 2010

The SLC30A8 gene encodes the zinc transporter ZnT-8, which provides zinc for insulin-hexamer formation. Genome-wide association studies have shown that a polymorphic variant in SLC30A8 is associated with altered susceptibility to Type 2 diabetes and we recently reported that glucose-stimulated insulin secretion is decreased in islets isolated from Slc30a8-knockout mice. The present study examines the molecular basis for the islet-specific expression of Slc30a8. VISTA analyses identified two conserved regions in Slc30a8 introns 2 and 3, designated enhancers A and B respectively. Transfection experiments demonstrated that enhancer B confers elevated fusion gene expression in both βTC-3 cells and αTC-6 cells. In contrast, enhancer A confers elevated fusion gene expression selectively in βTC-3 and not αTC-6 cells. These data suggest that enhancer A is an islet β-cell-specific enhancer and that the mechanisms controlling Slc30a8 expression in α- and β-cells are overlapping, but distinct. Gel retardation and ChIP (chromatin immunoprecipitation) assays revealed that the islet-enriched transcription factor Pdx-1 binds enhancer A in vitro and in situ respectively. Mutation of two Pdx-1-binding sites in enhancer A markedly reduces fusion gene expression suggesting that this factor contributes to Slc30a8 expression in β-cells, a conclusion consistent with developmental studies showing that restriction of Pdx-1 to pancreatic islet β-cells correlates with the induction of Slc30a8 gene expression and ZnT-8 protein expression in vivo.
Snapin deficiency is associated with developmental defects of the central nervous system
Authors: Zhou Bing , Zhu Yi-Bing , Lin Lin , Cai Qian , Sheng Zu-Hang
Published: October 2010

The autophagy–lysosomal pathway is an intracellular degradation process essential for maintaining neuronal homoeostasis. Defects in this pathway have been directly linked to a growing number of neurodegenerative disorders. We recently revealed that Snapin plays a critical role in co-ordinating dynein-driven retrograde transport and late endosomal–lysosomal trafficking, thus maintaining efficient autophagy–lysosomal function. Deleting snapin in neurons impairs lysosomal proteolysis and reduces the clearance of autolysosomes. The role of the autophagy–lysosomal system in neuronal development is, however, largely uncharacterized. Here, we report that snapin deficiency leads to developmental defects in the central nervous system. Embryonic snapin−/− mouse brain showed reduced cortical plates and intermediate zone cell density, increased apoptotic death in the cortex and third ventricle, enhanced membrane-bound LC3-II staining associated with autophagic vacuoles and an accumulation of polyubiquitinated proteins in the cortex and hippocampus. Thus our results provide in vivo evidence for the essential role of late endocytic transport and autophagy–lysosomal function in maintaining neuronal survival and development of the mammalian central nervous system. In addition, our study supports the existence of a functional interplay between the autophagy–lysosome and ubiquitin–proteasome systems in the protein quality-control process.
Proteinase 3 and prognosis of patients with acute myocardial infarction
Authors: Ng Leong L. , Khan Sohail Q. , Narayan Hafid , Quinn Paulene , Squire Iain B. , Davies Joan E.
Published: October 2010

A multimarker approach may be useful for risk stratification in AMI (acute myocardial infarction) patients, particularly utilizing pathways that are pathophysiologically distinct. Our aim was to assess the prognostic value of PR3 (proteinase 3) in patients post-AMI. We compared the prognostic value of PR3, an inflammatory marker, with an established marker NT-proBNP (N-terminal pro-B-type natriuretic peptide) post-AMI. We recruited 900 consecutive post-AMI patients (700 men; age, 64.6±12.4 years) in a prospective study with follow-up over 347 (0–764) days. Plasma PR3 was significantly higher in patients who died [666.2 (226.8–4035.5) ng/ml; P<0.001] or were readmitted with heart failure [598 (231.6–1803.9) ng/ml, P<0.004] compared with event-free survivors [486.9 (29.3–3118.2) ng/ml]. Using Cox modelling, log10 PR3 [HR (hazard ratio), 3.80] and log10 NT-proBNP (HR, 2.51) were significant independent predictors of death or heart failure. When patients were stratified by plasma NT-proBNP (median, 1023 pmol/l), PR3 gave additional predictive value for death or heart failure, in both the patients in whom NT-proBNP level was above the median (log rank for trend, 12.54; P<0.0004) and those with NT-proBNP level below the median (log rank for trend, 3.83; P<0.05). Neither marker predicted recurrent AMI. In conclusion, this is the first report showing a potential role for the serine protease PR3 in determining mortality and incidence of heart failure following AMI, independent of established conventional risk factors. PR3 may represent a clinically useful marker of prognosis after an AMI as part of a multimarker strategy.
Donepezil in schizophrenia — is it helpful? An experimental design case study
Authors: MacEwan G. W. , Ehmann T. S. , Khanbhai I. , Wrixon C.
Published: October 2010

Objective: To assess the clinical and cognitive effects of adding donepezil, a reversible acetylcholinesterase inhibitor, to the risperidone treatment of a high functioning stable out‐patient with schizophrenia.

Method: Case study using an experimental ABAB design. Assessments were completed objectively by standardized neuropsychological tests and clinical rating scales and subjectively with visual analogue scales.

Results: Strong improvements attributable to donepezil were found for verbal fluency and the patient's subjective response. No adverse changes were noted in psychiatric symptoms or side effects.

Conclusion: Cholinergic enhancement as an adjunctive treatment in schizophrenia should be explored in larger controlled trials.
Canine Uncemented Porous‐Coated Anatomic Total Hip Arthroplasty: Results of a Long‐Term Prospective Evaluation of 50 Consecutive Cases
Authors: Marcellin‐Little Denis J. , De Young Bonnie A. , Doyens David H. , De Dyoung David J.
Published: October 2010

Objective—To evaluate the long‐term clinical and radiographic results of a canine uncemented porous‐coated anatomic (PCA) total hip arthroplasty (THA).

Study Design—Prospective study of consecutive clinical patients using survival analysis.

Animals—Forty‐one dogs that underwent PCA THA; nine had bilateral PCA THA (50 prostheses).

Methods—Gait observation, orthopedic examination, and radiographic assessment were conducted before THA, 6 months after THA, and yearly thereafter. A zonal analysis system was used to document osseous changes in the femur and the acetabulum. Acetabular cup and femoral stem subsidence and migration, femoral canal fill, and implant orientation were measured. Survival analysis of the procedure was conducted.

Results—Long‐term follow‐up was available for 37 dogs (46 prostheses). The median follow‐up was 63 months. Limb function was normal for 37 limbs and abnormal for 9 limbs because of dislocation (n= 3), lumbosacral disease (n= 2), degenerative myelopathy (n= 1), autoimmune disease (n= 1), brain tumor (n= 1), or osteosarcoma of the femur (n= 1). All prosthetic stems and cups were fixed by bone ingrowth fixation. Osteolysis was not observed. Bone infarction occurred in five femoral canals (four dogs). The 6‐year survival rate for the procedure was 87% (95% confidence interval, 72%‐96%).

Conclusions—Long‐term fixation of the uncemented PCA acetabular cup and stem is successful in dogs, and long‐term clinical function is excellent.
Use of Omentum as a Physiologic Drain for Treatment of Chylothorax in a Dog
Authors: Williams John M. , Niles Jacqui D.
Published: October 2010

Objectives—To describe a novel technique for the surgical treatment of idiopathic chylothorax in a dog.

Animals—A 6‐year‐old, male Rhodesian Ridgeback, which presented with a history of reduced exercise tolerance and dyspnea.

Methods—Idiopathic chylothorax was diagnosed. Intermittent pleural drainage failed to resolve the problem. During surgery, extensive pleural fibrosis made it impossible to identify the thoracic duct. A dorsal omental pedicle was advanced through an incision in the diaphragm and into the cranial thoracic cavity to act as a physiological drain.

Results—The dog recovered well and has remained free from clinical signs of recurrence of the effusion (16 months at the time of writing).

Conclusions—The disease‐free interval achieved in this dog indicates that this novel technique is worthy of further consideration in the management of idiopathic chylothorax.
Effects of Hypertonic Saline Infusion on the Adrenocortical Response to Thiopental‐Halothane Anesthesia in Sheep After Premedication with Acepromazine
Authors: Taylor Polly Margaret
Published: October 2010

Objective—To investigate whether hypertonic saline infusion would prevent hypotension and pituitary‐adrenocortical axis activation during halothane anesthesia after acepromazine premedication and thiopental induction in sheep.

Study Design—Randomized crossover study.

Animals—Six Welsh Mountain ewes weighing 40 ± 2 kg and aged 2 to 3 years.

Methods—The sheep were studied on two occasions with 2 weeks between anesthetics. After acepromazine premedication, anesthesia was induced with thiopental and maintained for 120 minutes with halothane. During the first 15 minutes of anesthesia, 7.5% saline (4 mL/kg) was infused intravenously (HS group), but no infusion was given in the control (CONT) group. Sequential blood samples were taken for blood gas, cortisol, adenocorticotropic hormone (ACTH), glucose, and lactate assay.

Results—Hypotension developed in both treatments; blood pressure decreased to a nadir of 58 ± 5 mm Hg in the HS group and to 63 ± 4 mm Hg in the CONT group (P> .05). Plasma cortisol increased significantly in both groups, reaching a peak of 420 ± 130 nmol/L in HS and 483 ± 157 nmol/L in CONT (P> .05). ACTH increased similarly in both groups, reaching 128 ± 64 pmol/L in HS and 134 ± 55 pmol/L in CONT (P> .05). pH was slightly higher in CONT, but no other differences were detected between the two groups.

Conclusions—Hypertonic saline did not ameliorate the adrenocortical response during anesthesia; this may be a result of its failure to prevent the hypotension.
Standing Surgical Repair of Cystorrhexis in Two Mares
Authors: Rodgerson Dwayne H. , Spirito Michael A. , Thorpe Paul E. , Hanson R. Reid
Published: October 2010

Two surgical techniques were used to evert the bladder into the vagina for observation and repair of bladder tears that were associated with parturition. One technique involved an incision through the vaginal floor into the peritoneal cavity just caudal to the cervix, and prolapse of the bladder into the vagina. The second technique involved a 3‐cm incision through the urethra, 5 cm cranial to the urethral orifice, and digital exploration of the tear and finger traction to evert the bladder through the urethral incision. In both mares, the bladder defects were repaired in two layers, with use of 2–0 polyglycolic acid in a simple continuous pattern. After repositioning, the vaginal and urethral incisions were closed in single layers using absorbable suture material. A standing vaginal approach eliminates the need for general anesthesia and allows excellent observation and repair of bladder tears in adult mares.
Determination of the Minimum Alveolar Concentration of Isoflurane in Llamas
Authors: Mama Khursheed R. , Wagner Ann E. , Parker Denise A. , Hellyer Peter W. , Gaynor James S.
Published: October 2010

Objective—To determine the minimum alveolar concentration (MAC) of isoflurane (ISO) in llamas.

Study Design—Prospective study.

Animals—Eight adult neutered male llamas (9 ± 1 years [x̄± SD], 177 ± 29 kg).

Methods—Anesthesia was induced and maintained in otherwise unmedicated llamas with a mixture of ISO in oxygen administered through a standard small‐animal, semi‐closed circle system using an out‐of‐circle, agent‐specific vaporizer. The time from mask placement to intubation was recorded. Inspired and end‐tidal (ET) ISO was sampled continuously. At each anesthetic concentration, a constant ET ISO was maintained for at least 20 minutes before application of a noxious electrical stimulus (50 volts, 5 Hz, 10 ms for up to 1 minute). A positive or negative response to the stimulus was recorded, and ET ISO then increased (if positive response) or decreased (if negative response) by 10% to 20%. Individual MAC was the average of multiple determinations. Body temperature was maintained at 37 ± 1°C. Selected cardiopulmonary variables (heart rate [HR], respiratory rate [RR], arterial blood pressure [ABP]) and ET ISO were recorded at hourly intervals from first ISO. Arterial blood was collected for pH, PCO2, PO2analysis and measurement of packed cell volume (PCV) and total protein (TP) at 2 hour intervals. Following MAC determination, the anesthetic was discontinued and llamas were allowed to recover. Duration and quality of recovery were noted.

Results—The time from start of induction by mask to completion of intubation took 19.1 ± 4.8 minutes. The MAC of ISO corrected to one atmosphere at sea level (barometric pressure 760 mm Hg) in these llamas was 1.05 ± 0.17%. Mean ABP increased from 70 ± 26 mm Hg at the end of the first hour of anesthesia to 102 ± 7 mm Hg measured at the end of the sixth hour of anesthesia. ET ISO decreased from 2.06 ± 0.10% to 1.27 ± 0.07% over the same time period, but MAC did not change with time. The duration from first ISO to discontinuation of ISO averaged 6.19 ± 0.9 hours. Animals were able to support their heads in a sternal posture at 23 ± 10 minutes, and stood 62 ± 26 minutes following discontinuation of the anesthetic.

Conclusion—The MAC for ISO is similar to, but slightly lower than, values reported for other species.

Clinical Relevance—Knowledge of MAC may facilitate appropriate clinical use and provide the basis for future investigation of ISO in llamas.
Possible Hemolytic Uremic Syndrome in Three Cats After Renal Transplantation and Cyclosporine Therapy
Authors: Aronson Lillian R. , Gregory Clare
Published: October 2010

Objective— To describe the clinical history of 3 cats with possible hemolytic uremic syndrome (HUS) after renal transplantation.

Study Design— This case series documents historical findings, physical examination findings, clinical pathologic features, necropsy and histopathologic findings of 3 cats with possible HUS.

Results— Two cats had chronic renal failure; 1 cat had acute renal failure secondary to ethylene glycol toxicity. A renal transplant was performed in each of the 3 cats without obvious problems. Complications that would support a diagnosis of HUS, including anemia, thrombocytopenia, and azotemia occurred within 24 hours in 1 cat, within 8 days in a second cat, and 2 months after transplantation in the third cat. In 2 cats, HUS was likely secondary to cyclosporine immunosuppression. In the third cat, HUS may have been secondary to allograft rejection. Renal biopsies from all 3 cats were suggestive of HUS.

Conclusion and Clinical Relevance— In human beings, HUS in transplant recipients may occur secondary to immunosuppressive drugs, vascular rejection, or recurrence of original disease. Graft loss occurred in all 3 cats in this study and the mortality rate was 100%. Clinicians caring for these patients need to be aware of this disorder because early recognition and treatment is critical in the management of post‐transplant HUS.
Axial Pattern Flap Based on the Cutaneous Branch of the Superficial Temporal Artery in Dogs: An Experimental Study and Case Report
Authors: Fahie Maria A. , Smith Mark M.
Published: October 2010

Objective—To determine the anatomic guidelines and viability of an axial pattern flap based on the cutaneous branch of the superficial temporal artery (STA) in dogs. Application of the flap in a clinical patient is reported.

Study Design—Flap viability in control and experimental groups was determined 7 days postoperatively.

Animals—A total of 14 mature, mesaticephalic dogs; 1 clinical patient.

Methods—The cutaneous branch of the STA and vein were incorporated in the flaps of the experimental groups (group A,n = 5; group B,n = 4) and were ligated in the control group (n = 5). Flap length was extended in experimental group B. Seven days postoperatively, the length and area of tissue that remained viable in each flap was determined and compared with similar measurements performed intraoperatively. Cutaneous fluorescence was also used postoperatively to assess flap perfusion. The flap used in the clinical patient had the same dimensions as flaps developed in group A.

Results—Mean survival length (± SD) of STA flaps [group A, 9.1 (0.8) cm], was significantly increased (P< .05) compared with control flaps [7.0 (0.6) cm]. Percentage flap length survival (± SD) of STA flaps [group A, 91.8 (8.9)%], was significantly increased (P< .05) compared with control flaps [71.6 (7.0)%]. Mean percentage area of survival (± SD) of STA flaps [group A, 93.1 (7.5)%], was significantly increased (P< .05) compared with control flaps [73.5 (7.4)%]. Group B flaps had a mean survival length of 10.4 (1.1) cm, percentage flap length survival of 69.5 (4.8)%, and mean percentage area of survival of 69.1 (6.5)%. There was no positive correlation between the area of flap fluorescence at days 0, 1, and 3, and the area of flap survival. Application of the flap in a clinical patient allowed primary wound reconstruction with 100% survival.

Conclusion—A flap based on the cutaneous branch of the STA may be a source of skin for reconstructive procedures of the maxillofacial region in dogs.

Clinical Relevance—Knowledge of the anatomic landmarks and expected viability of a STA axial pattern flap is essential before consideration of its use as a reconstructive surgical technique.
The Effect of Oral Isoxsuprine and Pentoxifylline on Digital and Laminar Blood Flow in Healthy Horses
Authors: Ingle‐Fehr J. E. , Baxter G. M.
Published: October 2010

Objective—To quantitate blood flow in the palmar digital artery and dorsal laminae of the hoof in standing, unmedicated, nonsedated horses, and in horses treated with oral isoxsuprine, oral pentoxifylline, and intravenous acetylpromazine as a positive control.

Study Design—Experimental study; treatments administered in a random cross‐over design.

Animals—A total of 6 healthy horses selected with at least one nonpigmented forelimb hoof wall and determined to be free of laminitis.

Methods—All horses were instrumented with a flow probe placed around one palmar digital artery under general anesthesia and a laser doppler flow probe placed within a hole in the dorsal hoof wall to measure digital blood flow and laminar perfusion respectively. Baseline readings of palmar digital blood flow and laminar perfusion were recorded before and between treatments. Horses were randomly assigned to one of two groups and treated with either isoxsuprine (1.2 mg/kg, orally twice daily for 10 days) or pentoxifylline (4.4 mg/kg, orally every 8 hours for 10 days) in a random cross‐over design. Digital blood flow (DBF) and laminar perfusion (LP) were measured on days 2, 5, 7, and 10 of treatment. Horses also received acetylpromazine as a positive control (0.066 mg/kg, intravenously) during the washout period, and measurements were taken every 15 minutes until measurements returned to baseline readings. Data were analyzed by using repeated measures ANOVA.

Results—Digital blood flow (11.2 to 97.7 mL/min) and laminar perfusion (1.0 to 11.1 Capillary Perfusion Units) differed between horses. No statistically significant increases in DBF or LP were detected over the 10 day treatment period with either isoxsuprine or pentoxifylline. Acepromazine resulted in a significant increase (P= .0007) in DBF for approximately 75 minutes beginning 15 minutes after treatment. A mild but insignificant increase in LP was identified after acetylpromazine treatment.

Conclusion—Neither isoxsuprine nor pentoxifylline increased blood flow to the digit or dorsal laminae in healthy horses. Acepromazine caused an increased blood flow to the digit. Based on the results of this study acetylpromazine potentially would have a greater effect on improving digital blood flow than oral isoxsuprine or pentoxifylline when treating ischemic conditions of the foot in horses.
A Biomechanical Comparison of Screw and Wire Fixation With and Without Polymethylmethacrylate Re‐Enforcement for Acetabular Osteotomy Stabilization in Dogs
Authors: Lanz Otto I. , Lewis Daniel D. , Madison John B. , Miller Gary J. , Martin Daniel E.
Published: October 2010

Objective—Compare the biomechanical characteristics of screw and wire fixation with and without polymethylmethacrylate (PMMA) re‐enforcement for acetabular osteotomy stabilization in dogs.

Animals—Pelves removed from 8 adult mixed breed dogs weighing between 25 and 30 kg.

Procedure—The pubic symphysis of each pelvis was split and a central transverse acetabular osteotomy was performed. One hemipelvis from each dog was stabilized with the composite fixation (interfragmentary Kirschner wire, two screws and a figure‐of‐eight orthopedic wire with PMMA). The contralateral hemipelves was stabilized with an interfragmentary Kirschner wire, two screws, and a figure‐of‐eight orthopedic wire without PMMA. All hemipelves were tested in bending by using a materials testing machine at a cross head speed of 5 mm/min. An extensometer was placed on the dorsomedial surface of the hemipelves centered over acetabular osteotomy to record distraction of the osteotomy during loading. A load/deformation curve and a load/distraction curve was produced for each hemipelvis. The slope for the initial linear portion of the load/deformation curve and the load/distraction curve, yield load and maximum load sustained were compared between repair groups using a pairedt‐test withP< .05considered significant.

Results—The slope of the load/deformation curve was significantly greater (P= .001) for hemipelves stabilized with the composite fixation (mean ± SD: 69 ± 18 N/mm) compared with hemipelves stabilized without PMMA (mean ± SD: 39 ± 8 N/mm). There was no significant difference (P= .593) between repair groups in the slope of the load/distraction curves as measured on the extensometer. Yield load was significantly greater (P= .0002) for hemipelves stabilized with the composite fixation (mean ± SD: 184 ± 25 N) compared to hemipelves stabilized without PMMA (mean ± SD: 74 ± 12 N). Maximum load sustained was also significantly greater (P= .013) for hemipelves stabilized with the composite fixation (mean ± SD: 396 ± 71 N) compared to hemipelves stabilized without PMMA (mean ± SD: 265 ± 94 N). Failure of hemipelves stabilized with the composite fixation occurred primarily by ventrolateral bending of the cranial and caudal pelvic segments at the osteotomy site. Failure of hemipelves stabilized without PMMA occurred by ventrolateral bending of the cranial and caudal pelvic segments at the osteotomy site with pronounced concurrent ventrolateral rotation of the cranial pelvic segment.

Conclusion—PMMA improves the mechanical characteristics of acetabular fracture fixation, at least in part by neutralization of rotational forces. The results of this study justify use of PMMA as a component of the composite fixation when repairing acetabular fractures.
Closed Reduction and Lag Screw Fixation of Sacroiliac Luxations and Fractures
Authors: Tomlinson James L. , Cook James L. , Payne John T. , Anderson C. Collins , Johnson Jane C.
Published: October 2010

Objective—To describe a technique for closed reduction and percutaneous insertion of a lag screw for fixation of sacroiliac fracture‐luxations, and to report the success of this technique in stabilizing sacroiliac fracture‐luxations.

Study Design—A retrospective clinical study.

Study Population—13 consecutive client‐owned dogs with sacroiliac fracture‐luxations.

Methods—Sacroiliac fracture‐luxations were stabilized by using a closed reduction and percutaneous lag screw fixation technique. Preoperative, postoperative, and last re‐examination radiographs were used to assess the location and number of pelvic injuries, other orthopedic injuries, percent reduction of the sacroiliac joint, percent sacral width screw depth, position of the screw, pelvic canal diameter ratio, hemipelvic canal width ratio, and complications. Information on signalment, weight, weight‐bearing status, neurologic status, and complications was obtained from the medical record.

Results—Mean percent reduction of the sacroiliac joint was 92.33%. All screws were placed within the sacral body with a mean screw depth/sacral width of 79.03%. No screw loosening occurred. Mean pelvic canal diameter ratios were 0.99, 1.20, and 1.14 preoperatively, immediately postoperatively, and at the last re‐examination, respectively. Nine of 13 dogs were willing to walk on the ipsilateral rear leg the day after surgery.

Conclusions—Closed reduction and percutaneous insertion of a lag screw for stabilization of fracture‐luxation of the sacroiliac joint is an acceptable method of repair.

Clinical Relevance—Sacroiliac fracture‐luxations can be successfully reduced and stabilized using a minimally invasive technique.
Antibacterial Properties of a Silver Chloride‐Coated Nylon Wound Dressing
Authors: Adams A.P. , Santschi E.M. , Mellencamp M.A.
Published: October 2010

Objective—A silver chloride‐coated nylon wound dressing (Ag‐WD) was evaluated in vitro for antimicrobial activity against five common equine wound pathogens.

Study Design—Bacterial susceptibility study.

Sample Population—Equine wound pathogens:Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Streptococcus equisubspecieszooepidemicus,andStaphylococcus aureus.

Methods—An inoculum of each pathogen was incubated directly with Ag‐WD and quantitated after 24 to 48 hours of incubation. To determine if bactericidal activity of Ag‐WD was contact dependent, an inoculum ofE. coliandStaphylococcus aureuswas incubated separately from Ag‐WD by a filter and quantitated after 18 hours of incubation. Inductively coupled plasma emission spectrometry (ICP) determined the silver concentration of Mueller‐Hinton broth containing Ag‐WD after 24 hours of incubation. To establish if the rate of bacterial killing by Ag‐WD differed from a constant silver concentration, pathogens were exposed to a silver concentration of 6.45 μg/mL and quantitated after 18 hours.

Results—Direct exposure to Ag‐WD significantly reduced bacterial numbers after 15 minutes forK. pneumoniae,30 minutes forE. coli,1 hour forP. aeruginosa,and 2 hours forS. equisubspecieszooepidemicusandStaphylococcus aureus.Indirect exposure to Ag‐WD resulted in ≥99.9% and ≥90% kill of the inoculum doses ofE. coliat 2 hours andStaphylococcus aureusat 18 hours, respectively. Incubation of the pathogens at the constant silver concentration resulted in bacterial killing rates similar to those obtained by incubation with Ag‐WD.

Conclusions—In vitro, equine pathogens are effectively killed when exposed to Ag‐WD, and the rate of bacterial killing by Ag‐WD is similar to a constant silver concentration of 6.45 μg/mL.

Clinical Relevance—The in vitro antimicrobial properties of this silver‐coated nylon wound dressing are promising for future prevention of equine wound infections.
Evaluation of a Hemostasis Model for Teaching Ovariohysterectomy in Veterinary Surgery
Authors: Griffon Dominique J. , Cronin Paul , Kirby Barbara , Cottrell David F.
Published: October 2010

Objective—To evaluate the efficacy of a reusable plastic model mimicking the anatomy and hemodynamics of the canine female genital tract for teaching basic surgical skills and ovariohysterectomy.

Sample population—40 veterinary students of the class of 1998.

Study design—Prospective study.

Methods—Students'confidence level and experience in private practice was evaluated via questionnaire before training. Students in 2 groups performed an ovariohysterectomy on cadavers (group C,n= 20) or on the model (Group M,n= 20) for 2 hours. Students' psychomotor and basic surgical skills were objectively assessed by the following tests: ligation of a foam cylinder, passing a needle through the eyelets of an electronic suture board, and ligating latex tubing. Results were compared before and after training and within and between groups. The ability of students to perform an ovariohysterectomy in a live dog after training was compared between groups with a scoring system.

Results—Students in both groups had similar surgical experience and basic skills before training. The results of the psychomotor and basic surgical skills tests were better in group M after training than group C. The improvement of each student in performing these tasks also increased when students were trained with the model. Scores assigned to students performing an ovariohysterectomy in a live dog were higher in group M (31.45 ± 1.15) than in group C (20.7 ± 1.42).

Conclusion—The model was more effective than cadavers in teaching basic surgical skills and ovariohysterectomy in dogs.
Use of Atropine to Reduce Mucosal Eversion During Intestinal Resection and Anastomosis in the Dog
Authors: Agrodnia Marta , Hauptman Joe , Walshaw Richard
Published: October 2010

Objective—To determine whether atropine altered the degree of mucosal eversion during jejunal resection and anastomosis in the dog.

Study Design—Part I: Prospective, blinded, randomized, controlled study using a therapeutic dose (0.04 mg/kg systemic) of atropine. Part II: Prospective, unblinded, assigned, controlled study using a pharmacologic (0.04 mg/kg local arterial) dose of atropine.

Animals—Part I: Twenty‐two young adult female Beagle dogs used during a nonsurvival third‐year veterinary student surgical laboratory (small intestinal resection and anastomosis). Part II: Ten young adult female Beagle dogs used immediately after completion of a nonsurvival third‐year veterinary student orthopedic surgical laboratory.

Methods—Part I: Dogs were randomly assigned to receive either atropine (0.04 mg/kg), or an equal volume of saline, given intramuscularly (premedication) and again intravenously prior to intestinal resection. Part II: In each dog, atropine (0.04 mg/kg)/saline was alternately given in the proximal/distal jejunum.

Results—Part I: There was no clinically or statistically significant difference between systemic atropine and saline solution on the degree of jejunal mucosal eversion after resection. Part II: There was a statistically significant decrease in jejunal mucosal eversion with atropine compared with saline solution when injected into a local jejunal artery.

Conclusion—Systemic atropine (0.04 mg/kg) does not alter the degree of jejunal mucosal eversion during resection and anastomosis. Jejunal intraarterial atropine (0.04 mg/kg) reduced jejunal mucosal eversion during resection and anastomosis.

Clinical Relevance—The clinical usefulness and consequences of jejunal arterial atropine administration to reduce mucosal eversion remain to be determined.
Biomechanical Comparison of a Circular External Skeletal Fixator Construct to Pin and Tension Band Wire Fixation for the Stabilization of Olecranon Osteotomies in Dogs: A Cadaveric Study
Authors: Halling Krista B. , Lewis Daniel D. , Cross Alan R. , Sammy Richard J. , Rapoff Andrew J.
Published: October 2010

Objective—To compare anatomic reduction and the biomechanical properties of a circular external skeletal fixator (CESF) construct to pin and tension band wire (PTBW) fixation for the stabilization of olecranon osteotomies in dogs.

Study Design—Cadaveric study.

Animals—Forelimbs from 12 skeletally mature mixed‐breed dogs, weighing 23 to 28 kg.

Methods—An olecranon osteotomy was stabilized with either a CESF construct or PTBW fixation. A single distractive load to failure was applied to each specimen through the triceps tendon. Osteotomy reduction and biomechanical properties were compared between fixation groups.

Results—Reduction was not significantly different (gap:P= .171; malalignment:P= .558) between fixation groups. Osteotomies stabilized with the CESF had greater stiffness (P< .0001) and maximum load sustained (P< .0001) compared to PTBW fixation. There was no significant difference for yield load (P= .318) or for load at 1 mm of axial displacement (P= .997) between fixation groups. Failure of fixation occurred by bending of the intramedullary Steinmann pin and the fixation wires in the CESF specimens and by untwisting of the tension band wire knot with pullout and bending of the Kirschner wires in the PTBW specimens.

Conclusions—Specimens stabilized with the CESF construct had similar reduction and yield load, greater stiffness and maximum load sustained, and less elastic deformation than specimens stabilized with PTBW fixation.

Clinical Relevance—The CESF construct may provide a biomechanically favorable alternative to PTBW fixation for stabilization of olecranon osteotomies in dogs, and its application warrants clinical investigation.
Sodium Nitroprusside‐Induced Deliberate Hypotension to Facilitate Patent Ductus Arteriosus Ligation in Dogs
Authors: Hunter Suzanne L. , Culp Lindsey B. , Muir William W. , Lerche Phillip , Birchard Stephen J. , Smeak Daniel D. , McLoughlin Mary A.
Published: October 2010

Objective—To report the use of sodium nitroprusside to induce deliberate hypotension to reduce hemorrhage and facilitate surgical ligation of complicated patent ductus arteriosus (PDA) in dogs.

Study Design—Retrospective study.

Animals—Six dogs.

Methods—Hemorrhage occurred during surgical ligation of PDA in 5 dogs. Surgical dissection and isolation of the PDA were very difficult in a sixth dog that was considered to be at increased risk for ductus rupture. Sodium nitroprusside (5 to 25 μg/kg/min intravenously) was administered to these 6 dogs to induce hypotension to reduce blood loss and facilitate surgical ligation of the PDA.

Results—Sodium nitroprusside infusion reduced blood pressure (mean arterial pressure, 45 to 60 mm Hg) within 5 to 10 minutes and hemorrhage from the PDA, facilitating its surgical ligation. Recovery from surgery and anesthesia was uneventful in all 6 dogs.

Conclusions—Sodium nitroprusside infusion can be used to induce deliberate hypotension in dogs to facilitate surgical ligation of PDA.

Clinical Relevance—Sodium nitroprusside infusion produces hypotension within 5 to 10 minutes and is easy to control, rapidly abates, and should help to facilitate surgical ligation of PDA.
Monopolar versus bipolar electrocoagulation in canine laparoscopic ovariectomy: A nonrandomized, prospective, clinical trial
Authors: Van Goethem Bart E. B. J. , Rosenveldt Karin W. , Kirpensteijn Jolle
Published: October 2010

Objective—To compare the effect of using monopolar (MEC) or bipolar electrocoagulation (BEC) on surgical time for laparoscopic ovariectomy in dogs and to evaluate the influence of age, weight and obesity, and estrus or pseudopregnancy on surgical time.

Study Design—Prospective, nonrandomized, clinical trial.

Animals—One hundred three female dogs.

Methods—Laparoscopic ovariectomy was performed with MEC or BEC by 1 surgeon using a standard protocol. Surgical time was recorded for the different procedural stages and was statistically evaluated for differences between MEC and BEC (χ2, Studentttest, and ANOVA). The influence of significant variables was analyzed using multiple linear regression analysis.

Results—Mean surgical time was 47 minutes (range, 27 to 110 minutes). With BEC, surgical time was significantly shorter (41 minutes;P< .001) than with MEC (53 minutes). Obesity (56vs.42 minutes;P< .001) and intraoperative mesovarial bleeding (56vs.46 minutes;P= .03) increased surgical time. Dog age, estrus, and pseudopregnancy did not significantly influence surgical time.

Conclusions—BEC decreased laparoscopic ovariectomy time, decreased intraoperative hemorrhage, and, with the technique used, facilitated exteriorization of the ovaries.

Clinical Relevance—Laparoscopic ovariectomy can be performed more rapidly when using BEC instead of MEC and with less risk of mesovarial hemorrhage.
Scapulohumeral arthrodesis in miniature horses
Authors: Semevolos Stacy A. , Watkins Jeffrey P. , Auer Jörg A.
Published: October 2010

Objectives—To describe surgical arthrodesis of the scapulohumeral joint and to evaluate its efficacy in reducing morbidity associated with severe shoulder dysfunction in miniature horses.

Study Design—Retrospective study.

Animals—Four miniature horses.

Methods—Medical records and radiographs were reviewed for history, physical examination findings, lameness evaluation, radiographic evaluation, surgical techniques, postoperative complications, and outcome. A 10‐ or 11‐hole, 4.5‐mm narrow dynamic compression plate and 4.5‐mm cortical screws were applied to the cranial surface of the scapula and cranial surface of the humerus after osteotomy of the intermediate tubercle. In most horses, 1 or 2 screws were inserted in lag fashion across the joint, through holes in the plate.

Results—Scapulohumeral osteoarthritis was diagnosed radiographically in 4 horses, and 3 horses had concurrent shoulder luxation or subluxation. All horses had grade 3 or 4 lameness before surgery, and most improved by 1 to 2 grades after surgery. Despite complications of implant failure (2 horses), infection (2 horses), scapular fracture (1 horse), and atrophy of the shoulder muscles (1 horse), functional arthrodesis reduced morbidity in all horses.

Conclusions—Scapulohumeral arthrodesis facilitates early return to weight bearing in miniature horses with severe scapulohumeral joint osteoarthrosis. Despite functional gait abnormality, the horses ambulated quite well after surgery.

Clinical Relevance—Scapulohumeral arthrodesis should be considered for debilitating conditions of the shoulder joint in miniature horses, especially when the intended outcome is breeding or pasture soundness.
Traumatic atlanto‐occipital luxation in a dog: Associated hypoglossal nerve deficits and use of 3‐dimensional computed tomography
Authors: Steffen Frank , Flueckiger Mark , Montavon Pierre M.
Published: October 2010

Objective— To present a detailed description of a dog with atlanto‐occipital (A–O) luxation, including results of the neurologic examination, diagnostic imaging, and treatment by closed reduction.

Study Design— Clinical case report.

Sample Population— One adult intact male German shepherd dog.

Results— Neurologic signs included nonambulatory tetraparesis and neck pain. An apparent hypoglossal nerve deficit was consistent with a lesion at the peripheral part of the nerve in the region of the craniocervical junction. Radiographic examination revealed a left‐sided luxation of the A–O joint, and fractures were excluded with the aid of computed tomography (CT). Closed reduction of the luxated articulation resulted in a stable A–O joint, and complete neurologic recovery occurred within 4 weeks.

Conclusions— Hypoglossal nerve deficits may be associated with A–O luxation.

Clinical Relevance— Closed reduction of a unilateral, traumatic luxation of the A–O joint is a therapeutic option in dogs. CT imaging, especially 3‐dimensional reconstruction, was considered helpful in excluding fractures as well as defining treatment options.
In vitro comparison of equine cancellous bone graft donor sites and tibial periosteum as sources of viable osteoprogenitors
Authors: McDuffee Laurie A. , Anderson Gail I.
Published: October 2010

Objective— To compare the osteogenic potential of cancellous bone of conventional graft sites with that of one nonconventional site (fourth coccygeal vertebra) and to investigate the tibial periosteum as a donor site with respect to osteogenic potential.

Study Design— In vitro osteogenic cell culture system.

Sample Population— Eight adult horses.

Methods— Cancellous bone or tibial periosteum was aseptically collected and cut into bone chips or periosteal strips of 1 to 2 mm3 for primary explant cultures. After 2 weeks, primary tissue cultures that yielded a population of osteogenic cells were counted and subcultured at 1 × 105 cells/35‐mm dish in osteogenic media. After 7 to 10 days, subcultures were stained with Von Kossa (VK) to assess mineralized bone nodule formation. VK‐positive bone nodules were counted as osteoprogenitors and compared among 3 donor sites, which provided consistent primary osteogenic cells (tuber coxae, fourth coccygeal vertebra, periosteum) using ANOVA (P < .05).

Results— Sternal and tibial bone yielded viable osteogenic cells from 25% and 50% of horses, respectively, whereas yields from tuber coxae, coccygeal vertebra, and periosteum were 75%, 100%, and 100%, respectively. Tuber coxae and periosteum had significantly greater numbers of osteoprogenitors compared with fourth coccygeal vertebra.

Conclusions— Among the conventional donor sites, tuber coxae most consistently yielded viable osteogenic cells with an acceptable percentage of osteoprogenitors. Sternal and tibial sites were unreliable in providing osteogenic cells. Two new donor sites, the fourth coccygeal vertebra and tibial periosteum, were tissues with good osteogenic potential.

Clinical Relevance— When a source of transplantable viable osteoprogenitor cells is desired, use of the tuber coxae as a conventional donor site is warranted. Use of tibial periosteum or fourth coccygeal vertebra as reliable sources of transplantable osteoprogenitors should be considered.
AC measurement of heat capacity and magnetocaloric effect for pulsed magnetic fields
Authors: Kohama Yoshimitsu , Marcenat Christophe , Klein Thierry , Jaime Marcelo
Published: October 2010

A new calorimeter for measurements of the heat capacity and magnetocaloric effect of small samples in pulsed magnetic fields is discussed for the exploration of thermal and thermodynamic properties at temperatures down to 2 K. We tested the method up to μ0H=50 T, but it could be extended to higher fields. For these measurements we used carefully calibrated bare-chip Cernox® and RuO2 thermometers, and we present a comparison of their performances. The monotonic temperature and magnetic field dependences of the magnetoresistance of RuO2 allow thermometry with a precision as good as ±4 mK at T=2 K. To test the performance of our calorimeter, heat capacity and magnetocaloric effect for the spin-dimer compound Sr3Cr2O8 and the triangular lattice antiferromagnet RbFe(MoO4)2 are presented.
Nonlinear fan instability of electromagnetic waves
Authors: Krafft C. , Volokitin A.
Published: October 2010

This paper studies the linear and nonlinear stages of the fan instability, considering electromagnetic waves of the whistler frequency range interacting resonantly with energetic electron fluxes in magnetized plasmas. The main attention is paid to determine the wave-particle interaction processes that can lead to the excitation of intense electromagnetic waves by nonequilibrium particle distributions involving suprathermal tails, and to explain under what conditions and through what mechanisms they can occur, develop, and saturate. This paper presents and discusses two main processes: (i) the linear fan instability and (ii) the nonlinear process of dynamical resonance merging, which can significantly amplify the energy carried by linearly destabilized waves after they saturate due to particle trapping. This study consists of (i) determining analytically and numerically, for parameters typical of space and laboratory plasmas, the linear growth rates of whistlers excited by suprathermal particle fluxes through the fan instability, as well as the corresponding thresholds and the physical conditions at which the instability can appear, (ii) building a theoretical self-consistent 3D model and a related numerical code for describing the nonlinear evolution of the wave-particle system, and (iii) performing numerical simulations to reveal and characterize the nonlinear amplification process at work, its conditions of development, and its consequences, notably in terms of electromagnetic wave radiation. The simulations show that when the waves have reached sufficient energy levels owing to the linear fan instability, they saturate by trapping particles and due to the complex dynamics of these particles in the electromagnetic fields, the resonant velocities’ domains of the waves overlap and merge, meanwhile a strong increase of the wave energy occurs.
Photoionized astrophysical plasmas in the laboratory
Authors: Hill Edward , Rose Steven
Published: October 2010

The time-dependent collisional-radiative code ALICE [E. G. Hill and S. J. Rose, High Energy Density Phys. 5, 302 (2009)] is used to model the spectrum from a laboratory photoionized silicon plasma [S. Fujioka et al., Nat. Phys. 5, 821 (2009)]. The results show a good agreement with the laboratory spectrum and lend support to the accompanying analytical discussion of photoionized laboratory spectra, their parametrization, and relevance to astrophysics.
Convergent ablator performance measurements
Authors: Hicks D. G. , Spears B. K. , Braun D. G. , Olson R. E. , Sorce C. M. , Celliers P. M. , Collins G. W. , Landen O. L.
Published: October 2010

The velocity and remaining ablator mass of an imploding capsule are critical metrics for assessing the progress toward ignition of an inertially confined fusion experiment. These and other convergent ablator performance parameters have been measured using a single streaked x-ray radiograph. Traditional Abel inversion of such a radiograph is ill-posed since backlighter intensity profiles and x-ray attenuation by the ablated plasma are unknown. To address this we have developed a regularization technique which allows the ablator density profile ρ(r) and effective backlighter profile I0(y) at each time step to be uniquely determined subject to the constraints that ρ(r) is localized in radius space and I0(y) is delocalized in object space. Moments of ρ(r) then provide the time-resolved areal density, mass, and average radius (and thus velocity) of the remaining ablator material. These results are combined in the spherical rocket model to determine the ablation pressure and mass ablation rate during the implosion. The technique has been validated on simulated radiographs of implosions at the National Ignition Facility [Miller et al., Nucl. Fusion 44, 228 (2004)] and implemented on experiments at the OMEGA laser facility [Boehly et al., Opt. Commun. 133, 495 (1997)].
The axisymmetric collapse of a mixed patch and internal wave generation in uniformly stratified fluid
Authors: Holdsworth Amber M. , Décamp Sabine , Sutherland Bruce R.
Published: October 2010

Laboratory experiments are used to investigate the axisymmetric collapse of a localized mixed region in uniformly stratified ambient. The collapsing fluid forms an intrusion and generates vertically propagating internal gravity waves in the stratified ambient. The speed of the intrusion is found to be (0.085±0.001)N0Hm where Hm is the depth of the mixed patch and N0 is the buoyancy frequency. Internal wave frequencies are set by the buoyancy frequency, (ω≃0.8N0), and the effective horizontal wavenumber is set by the radius of the cylinder so that kr≃2Rc. Vertical displacement amplitudes scale with the depth of the mixed patch according to |ξ|/(Hm/2)=0.032±0.002 and we find that about 2% of the available potential energy of the mixed region is extracted by the internal waves. Extrapolation of these results to oceanic circumstances of mixed region collapse beneath a hurricane gives a conservative estimate of the power extracted by internal waves during the lifecycle of the storm is estimated to range from 6×1010 to 4×1012 W. The corresponding power from all hurricanes averaged over the course of a year can range from 1×109 to 8×109 W.