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  • Author or Editor: Timothy B. Hackett x
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Abstract

Objective—To establish an immortalized cell line and transplantable xenograft of feline bronchioloalveolar lung carcinoma (BAC).

Sample Population—Pleural effusion from a 12-yearold Persian male cat with BAC.

Procedure—Tumor cells from the pleural effusion were grown in monolayer cell culture and injected into severe combined immunodeficient (SCID) mice to establish an immortalized cell line as well as a transplantable xenograft.

Results—Both the primary lung carcinoma, the derived cell line, and the transplantable xenograft had evidence of a type-II pneumocyte origin expressing lamellar bodies ultrastructurally and thyroid transcription factor-1 and surfactant immunocytochemically. All 3 also expressed nuclear p53 immunoreactivity. A metaphase spread of the cell line (SPARKY) probed with fluorescein-labeled genomic feline DNA gave evidence of its feline origin. Flow cytometric studies indicated aneuploidy with a DNA index of 1.6. An R-banded karyotype revealed a modal number of 66 including the feline Y chromosome. The cell line had a doubling time of 16 hours. The xenograft (SPARKY-X) reached a diameter of 1 cm in 3 weeks in SCID mice. Deoxyribonucleic acid fingerprint analysis revealed that SPARKY and SPARKY-X were novel and strongly matched each other, except for the murine component found in SPARKY-X. Interestingly, SPARKY-X manifested the characteristic lepidic growth pattern of pulmonic BAC.

Conclusions—Both the cell line and xenograft retained their autochthonous BAC phenotype, making them useful for the subsequent dissection of molecular abnormalities in feline BAC and in vitro screening of chemotherapeutic agents. (Am J Vet Res 2002; 63:1745–1753)

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in American Journal of Veterinary Research
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine the frequency of canine and feline emergency visits with respect to the lunar cycle.

Design—Retrospective case series.

Animals—11,940 dogs and cats evaluated on an emergency basis during an 11-year period.

Procedures—Date of emergency visit, signalment, and chief complaint were retrieved from a medical records database. Emergency type was categorized as animal bite, cardiac arrest, epilepsy, ophthalmic, gastric dilatation-volvulus, trauma, multiple diseases, neoplasia, or toxicosis. The corresponding lunar phase was calculated and recorded as new moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, last quarter, or waning crescent. The effect of lunar phase on the frequency of emergency visits was evaluated by calculating relative risk.

Results—Of 11,940 cases, 9,407 were canine and 2,533 were feline. Relative risk calculations identified a significant increase in emergencies for dogs and cats on fuller moon days (waxing gibbous to waning gibbous), compared with all other days.

Conclusions and Clinical Relevance—Results suggested that more emergency room visits occurred on fuller moon days for dogs and cats. It is unlikely that an attending clinician would notice the fractional increase in visits (0.59 and 0.13 more canine and feline visits, respectively) observed in this study at a facility with a low caseload. If the study is repeated at a facility with a robust emergency caseload, these results may lead to reorganization of staffing on fuller moon dates. A prospective study evaluating these findings under conditions of high caseload is necessary to determine the clinical relevance.

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in Journal of the American Veterinary Medical Association

Abstract

Case Description—A 6-year-old castrated male Llewelyn Setter was evaluated because of an acute onset of myalgia and respiratory distress.

Clinical Findings—Physical examination revealed a stiff stilted gait, swollen muscles that appeared to cause signs of pain, panting, and ptyalism. The dog had a decrease in palpebral reflexes bilaterally and a decrease in myotatic reflexes in all 4 limbs. The panniculus reflex was considered normal, and all other cranial nerve reflexes were intact. Serum biochemical analysis revealed markedly high cardiac troponin-I concentration and creatine kinase and aspartate aminotransferase activities. Urinalysis revealed myoglobinuria. Results for thoracic and abdominal radiography, blood pressure measurement, and an ECG were within anticipated limits. Echocardiographic findings were consistent with secondary systolic myocardial failure. Arterial blood gas analysis confirmed hypoxemia and hypoventilation. The dog had negative results when tested for infectious diseases. Examination of skeletal muscle biopsy specimens identified necrotizing myopathy.

Treatment and Outcome—Treatment included ventilatory support; IV administration of an electrolyte solution supplemented with potassium chloride; administration of dantrolene; vasopressor administration; parenteral administration of nutrients; use of multimodal analgesics; administration of clindamycin, furosemide, mannitol, and enrofloxacin; and dietary supplementation with L-carnitine and coenzyme Q10. Other medical interventions were not required, and the dog made a rapid and complete recovery.

Clinical Relevance—Necrotizing myopathy resulting in rhabdomyolysis and myoglobinuria can lead to life-threatening physical and biochemical abnormalities. Making a correct diagnosis is essential, and patients require intensive supportive care. The prognosis can be excellent for recovery, provided there is no secondary organ dysfunction.

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in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association

Abstract

Objective—To identify the prevalence of DNA of Mycoplasma haemofelis; ‘Candidatus Mycoplasma haemominutum’; Anaplasma phagocytophilum; and species of Bartonella, Neorickettsia, and Ehrlichia in blood of cats used as blood donors in the United States. Design—Prospective study.

Animals—146 cats that were active blood donors.

Procedures—Environmental history was requested for each blood-donor cat from which a blood sample (mixed with EDTA) was available. Polymerase chain reaction assays capable of amplifying the DNA of the microorganisms of interest following DNA extraction from blood were performed.

Results—Overall, DNA of one or more of the infectious agents was detected in blood samples from 16 of 146 (11%) feline blood donors. Twenty-eight laboratory-reared cats housed in a teaching hospital had negative results for DNA of all organisms investigated. The DNA of at least 1 infectious agent was amplified from blood samples collected from 16 of 118 (13.6%) community-source cats; assay results were positive for ‘Candidatus M haemominutum,’ M haemofelis, or Bartonella henselae alone or in various combinations. Of the community-source cats allowed outdoors (n = 61) or with known flea exposure (44), DNA for a hemoplasma or B henselae was detected in 21.3% and 22.7%, respectively.

Conclusions and Clinical Relevance—When community-source cats, cats allowed outdoors, or cats exposed to fleas are to be used as blood donors, they should be regularly assessed for infection with M haemofelis,Candidatus M haemominutum,’ and Bartonella spp, and flea-control treatment should be regularly provided.

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in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE

To assess signalment, clinical findings, and treatments for New World camelids (NWCs) hospitalized for evaluation and treatment of neonatal disorders and investigate associations between these factors and death during and after hospitalization.

ANIMALS

267 NWCs ≤ 30 days of age.

PROCEDURES

Medical records of a veterinary teaching hospital were retrospectively reviewed to identify NWCs admitted for evaluation and treatment of neonatal disorders between 2000 and 2010. Signalment, physical examination data, diagnostic findings, treatments, and outcomes were recorded. Factors were examined for association with death during hospitalization and the overall hazard of death by use of multivariable logistic regression and Cox proportional hazards analysis, respectively.

RESULTS

The sample comprised alpacas (n = 255) and llamas (12). Median age at admission was 3 days, and median hospitalization time was 2 days; 208 of the 267 (77.9%) neonatal NWCs survived to hospital discharge. Factors associated with increased odds of death during hospitalization included prematurity or dysmaturity, hypothermia, sepsis, toxic changes in neutrophils, and undergoing surgery. The odds of death during hospitalization also increased as anion gap increased. After discharge, 151 of 176 (85.8%) animals had follow-up information available (median follow-up time, 2,932 days); 126 (83%) were alive and 25 (17%) had died. Prematurity or dysmaturity, congenital defects, sepsis, oxygen administration, and undergoing surgery as a neonate were associated with an increased hazard of death; the hazard of death also increased as serum chloride concentration at the time of hospitalization increased.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggested the prognosis for survival during and after hospitalization is good for most NWCs hospitalized because of neonatal disorders.

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in Journal of the American Veterinary Medical Association

Abstract

Objective—To compare outcome and intermediateterm survival for dogs undergoing open surgical correction of subvalvular aortic stenosis (SAS) with those for dogs with SAS that did not undergo surgery.

Design—Retrospective study.

Animals—44 dogs with congenital SAS.

Procedure—Maximum instantaneous systolic pressure gradients were determined by use of Doppler echocardiography. Cardiopulmonary bypass and open surgical correction of SAS (membranectomy with or without septal myectomy) was performed in 22 dogs, whereas 22 dogs did not undergo surgical correction. Cumulative survival was compared between surgical and nonsurgical groups, using Kaplan-Meier nonparametric analysis and a Mantel-Cox log-rank test.

Results—Initial systolic pressure gradients were not significantly different for dogs undergoing surgery (128 ± 55 mm Hg), compared with those that did not undergo surgery (117 ± 57 mm Hg). Systolic pressure gradients were significantly decreased after surgery in dogs that underwent surgery (54 ± 27 mm Hg). Cumulative survival was not significantly different between dogs in the surgical and nonsurgical groups. Censoring surgery-related mortality in the analysis still did not reveal a significant difference in cumulative survival between the surgical and nonsurgical groups.

Conclusion and Clinical Relevance—Despite reductions in the systolic pressure gradient and possible associated improvement in exercise tolerance, a palliative benefit on survival was not documented in dogs undergoing surgery for SAS. (J Am Vet Med Assoc 2000;216:364–367)

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in Journal of the American Veterinary Medical Association

Abstract

Objective—To evaluate changes in resting energy expenditure (REE) as well as protein and carbohydrate metabolism in dogs with osteosarcoma (OSA).

Animals—15 weight-stable dogs with OSA that did not have other concurrent metabolic or endocrine illness and twelve 1-year-old sexually intact female Beagles (control dogs).

Procedures—Indirect calorimetry was performed on all dogs to determine REE and respiratory quotient (RQ). Stable isotope tracers (15N-glycine, 4.5 mg/kg of body weight, IV; 6,6-deuterium-glucose, 4.5 mg/kg, IV as a bolus, followed by continuous-rate infusion at 1.5 mg/kg/h for 3 hours) were used to determine rate of protein synthesis and glucose flux in all dogs. Dualenergy x-ray absorptiometry (DEXA) scans were performed to determine total body composition.

Results—Accounting for metabolic body size, REE in dogs with OSA was significantly higher before and after surgery, compared with REE of healthy control dogs. The RQ values did not differ significantly between groups. Dogs with OSA also had decreased rates of protein synthesis, increased urinary nitrogen loss, and increased glucose flux during the postoperative period.

Conclusions and Clinical Relevance—Alterations in energy expenditure, protein synthesis, urinary nitrogen loss, and carbohydrate flux were evident in dogs with OSA, similar to results documented in humans with neoplasia. Changes were documented in REE as well as protein and carbohydrate metabolism in dogs with OSA. These changes were evident even in dogs that did not have clinical signs of cachexia. (Am J Vet Res 2001;62:1234–1239)

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in American Journal of Veterinary Research