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Biomedical subjects

A S Moore

Publications and source records attributed to A S Moore.

At least 19 recordsLinked to original sources
PubMed2004

p53 expression and environmental tobacco smoke exposure in feline oral squamous cell carcinoma.

The purpose of this study was to determine the prevalence of p53 overexpression in feline oral squamous cell carcinomas (SCC) and to determine, if any, the association between p53 overexpression and lifestyle factors and environmental exposures, including exposure to environmental tobacco smoke (ETS). Questionnaires concerning exposure to ETS and other environmental factors were sent to owners of cats presenting to the Harrington Oncology Program with a diagnosis of oral SCC between 1991 and 2000. Additionally, 23 formalin-fixed biopsy samples from these cats, with information regarding ETS, were evaluated immunohistochemically for p53 expression using the CM-1 clone and the avidin-biotin-horseradish peroxidase method. Of the 23 samples evaluated, 15 (65%) showed positive nuclear staining for the CM-1 clone. Tumor biopsy samples from cats exposed to any ETS were 4.5 times more likely to overexpress p53 than were tumors from unexposed cats (P = 0.19). Among cats with any ETS exposure, those with 5 years or longer of exposure were 7.0 times more likely to overexpress p53 (P = 0.38). Longhaired cats (P = 0.18) and female cats (P = 0.35) were also more likely to show p53 expression in their tumors. These results provide additional support for a relationship between oral SCC development and exposure to household ETS and may implicate p53 as a potential site for carcinogen-related mutation in this tumor.

Animals↗
PubMed2003

An immunohistochemical study of cyclooxygenase-2 expression in various feline neoplasms.

Cyclooxygenase (COX) enzymes catalyze the synthesis of prostaglandins and exist as two isoforms, COX-1 and COX-2. COX-2 is a potent inducible mediator of inflammation. COX-2 is also upregulated in several human tumors and in canine squamous cell, renal cell, and transitional cell carcinomas, prostatic adenocarcinoma, and intestinal neoplasia. The purpose of this study was to determine whether COX-2 is expressed in various feline tumors. Results of this study may help determine whether COX-2 is a potential target for therapeutic and preventive strategies in cats. Immunohistochemical studies were performed on paraffin-embedded tissues using the amplified streptavidin-biotin-horseradish peroxidase system. COX-2 was found in 7 of 19 (37%) feline transitional cell carcinomas and in 2 of 21 (9%) feline oral squamous cell carcinomas. No COX-2 immunoreactivity was detected in cutaneous squamous cell carcinomas (6), adenocarcinomas (nine mammary, eight pulmonary, seven intestinal), lymphomas (six nasal, six intestinal), or 10 vaccine-associated sarcomas. The widespread absence of COX-2 expression in most feline neoplasms might suggest that COX-2 inhibitors would have a low potential as anticancer agents.

Adenocarcinoma↗
PubMed2001

Use of carboplatin for treatment of dogs with malignant melanoma: 27 cases (1989-2000).

OBJECTIVE: To evaluate response rate and duration of malignant melanomas in dogs treated with carboplatin. DESIGN: Retrospective study. ANIMALS: 27 client-owned dogs with spontaneously occurring measurable malignant melanomas. PROCEDURE: Records of dogs with melanomas treated with carboplatin from October 1989 to June 2000 were reviewed. Carboplatin was administered IV at doses of 300 or 350 mg/m2 of body surface area. Response to treatment and evidence of drug toxicity were determined. RESULT: Response to treatment could be evaluated in 25 dogs. Of those, overall response rate was 28%. One dog had a complete response, 6 (24%) dogs had a partial response (> 50% reduction in tumor burden). Median duration of partial response was 165 days. Eighteen dogs had stable disease (n = 9; 36%) or progressive disease (9; 36%). Response to treatment was significantly associated with carboplatin dose on a milligram per kilogram basis (15.1 mg/kg 16.9 mg/lb] of body weight vs 12.6 mg/kg [5.7 mg/lb]). Evidence of gastrointestinal toxicosis could be assessed in 27 dogs. Mean body weight of 5 dogs that developed gastrointestinal toxicosis was significantly less than that of 22 dogs without gastrointestinal toxicosis (9.9 kg [21.8 lb] vs 19.3 kg [42.5 lb]). CONCLUSIONS AND CLINICAL RELEVANCE: Carboplatin had activity against macroscopic spontaneously occurring malignant melanomas in dogs and should be considered as an adjunctive treatment for microscopic local or metastatic tumors. Gastrointestinal toxicosis was associated with body weight. Because small dogs are more likely to have adverse gastrointestinal effects, gastrointestinal protectants should be considered for these patients.

Animals↗
PubMed2000

Induction of cyclooxygenase-2 by overexpression of the human catalase gene in cerebral microvascular endothelial cells.

Prostaglandin (PG) formation by the inducible (type 2) cyclooxygenase (COX-2) and reactive oxygen species (ROS) have been proposed to play important roles in cerebrovascular pathological processes. To explore the relationship between ROS and COX-2 expression, adenovirus (Ad) vectors containing cDNA for human antioxidant enzymes including catalase (AdCAT:), copper/zinc superoxide dismutase (AdCu/ZnSOD), and manganese superoxide dismutase (AdMnSOD) were transferred into murine cerebral microvascular endothelial cells. AdCAT: (100 multiplicity of infection) infection increased the content and enzymatic activity of cellular Cat threefold and decreased the intracellular peroxide level. The expression of COX-2 mRNA and protein in cell lysates was up-regulated, and the amount of PGE(2) formed from exogenous arachidonic acid increased following AdCAT: infection in a dose-dependent manner, paralleling the expression of COX-2 protein. The AdCAT:-induced increase in PGE(2) formation was inhibited by NS-398, a selective inhibitor of COX-2 enzymatic activity. AdCAT: infection did not change the expression of the constitutive (type 1) COX protein. Although AdCu/ZnSOD and AdMnSOD infection increased the expression of superoxide dismutase proteins, COX-2 expression was not induced. An in vitro nuclear transcription assay indicated that overexpression of the Cat gene increases the transcription of the COX-2 gene. Furthermore, the stability of COX-2 mRNA induced by lipopolysaccharide was increased after AdCAT: gene transfer. These results indicate that AdCAT: gene transfer induces the transcriptional activation of the COX-2 gene and increases COX-2 mRNA stability. Therefore, peroxide may have regulatory effect on COX-2 function in the cerebral microcirculation.

Animals↗
PubMed2000

Radiation therapy for long-term control of odontogenic tumours and epulis in three cats.

Orthovoltage radiation was used to treat odontogenic tumours in three cats following incomplete surgical resection. Cats received a total radiation dose of 48-52 Gy over a period of 26-29 days. Acute toxicities were mild, consisting of hair loss within the radiation field in all cats, and mild mucositis in one cat. All cats had long-term (>35 months) control of their tumour, and two cats are still alive without recurrence of tumour 60 and 39 months, respectively, after completing treatment. Radiation therapy should be considered to be an adjuvant to incomplete surgery in cats with odontogenic neoplasms or epulides.

Animals↗
PubMed2000

Feline non-ocular melanoma: a retrospective study of 23 cases (1991-1999).

Non-ocular melanoma is considered to be a rare neoplasm in cats; however, more than 150 cases have been reported in the literature since 1961. The objective of this study was to characterise this tumour better by evaluating case outcome and survival data for cats with melanoma and to compare clinical and histopathological findings with those of previous reports. Twenty-three feline non-ocular melanomas were identified, the most common locations being the nose, digit and pinna. Cats with digital melanomas had survival rates similar to their canine counterparts. Histological assignation of benignity, malignancy or junctional activity was not found to be an accurate predictor of clinical behaviour. Melanoma should be considered as a differential diagnosis for cats presenting with pigmented or non-pigmented masses and histopathology is essential for definitive diagnosis, as other tumours may clinically appear quite similar. Regular follow-up examinations are recommended indefinitely for benign or malignant feline melanomas.

Animals↗
PubMed1998

Searching the medical literature.

The widespread use of computers and the Internet have made searching the medical literature easier and more accessible to most physicians. The National Library of Medicine (NLM) maintains MEDLINE, a comprehensive, cross-referenced database of citations to the medical literature covering 1966 to the present. The NLM maintains several other literature databases that are also available online. In 1996, the NLM began providing free, unlimited access to MEDLINE to all Americans over the World Wide Web. This article discusses how to perform effective and efficient literature searches using MEDLINE and other databases.

Information Storage and Retrieval↗
PubMed1998

Photodynamic therapy of naturally occurring tumors in animals using a novel benzophenothiazine photosensitizer.

5-Ethylamino-9-diethylaminobenzo[a]phenothiazinium chloride (EtNBS) is a novel photodynamic therapy (PDT) photosensitizer with efficacy against experimental murine tumors. In this preliminary study, dogs and cats with naturally occurring tumors were treated with EtNBS-PDT to determine safety and efficacy. Fifteen treatments were performed on 13 animals (9 treatments in 8 cats and 6 treatments in 5 dogs), generally using 400 J of 652 nm light. Two feline sublingual squamous cell carcinomas (SCCs) responded briefly (minor response). Six feline facial SCCs were treated, resulting in two partial responses and four long-term complete responses (CR). Two canine intraoral SCCs were treated; one responded minimally for 2 weeks (minor response), and one achieved long-term CR. One canine cutaneous mast cell tumor achieved CR, and one canine ocular mast cell tumor responded briefly. One canine ocular melanoma did not respond to treatment. Systemic reactions included nausea associated with photosensitizer injection in two cats and two dogs, elevated body temperatures during treatment in two dogs, elevated body temperature 2 days after PDT in one cat, and inappetance for 2 weeks in one cat. A peripheral neuropathy of undetermined cause occurred in one cat 2 weeks after PDT and resolved without treatment. Local reaction was well tolerated in 13 of 15 treatments. All animals were exposed to normal daylight after less than 5 days (mean, 3.5 days) without residual photosensitization. EtNBS-PDT is safe for dogs and cats and has activity against selected naturally occurring tumors, with an overall objective response rate (partial response + CR) of 61.5%.

Animals↗
PubMed1996

A cellular mechanism for imidocarb retention in edible bovine tissues.

Imidocarb dipropionate, formulated as Imizol, is used for the treatment and prophylaxis of bovine babesiosis. Several studies have shown that imidocarb remains detectable in edible ovine and bovine tissues for several months after dosing but the mechanism of retention remains unknown. In this study, the mechanism of imidocarb retention was investigated by measuring the binding of [14C]imidocarb to bovine hepatocytes, erythrocytes, sub-cellular fractions and isolated bovine macromolecules. The proportion of [14C]imidocarb (10 microM) bound to cells in suspension culture (1 x 10(7) cells.ml-1) was found to be substantially greater to hepatocytes (56.5%) than to erythrocytes (4.6%). Studies with washed erythrocytes reconstituted in plasma indicated that approximately 70% of the [14C]imidocarb was bound to plasma proteins, 10% to erythrocytes, and 20% remained free. Measurement of [14C]imidocarb binding to sub-cellular fractions prepared from bovine liver revealed preferential accumulation in the nuclear, rather than in the mitochondrial, microsomal or cytosolic fractions. Binding capacities of selected bovine macromolecules for [14C]imidocarb were in the order deoxy-ribonucleic acid (DNA) = ribonucleic acid (RNA) > > alpha 1-acid glycoprotein (AGP) > serum albumin (BSA) > haemoglobin (Hb). DNA binding sites for imidocarb remained unsaturated over the concentration range 0-100 microM [14C]imidocarb. Competitive binding studies between imidocarb and pentamidine or spermidine provided evidence for common DNA binding sites. These studies indicated that preferential binding of [14C]imidocarb to hepatocytes compared with erythrocytes observed in vitro was a result of substantial reversible binding to nucleic acids and that the same cellular mechanism may be implicated in the slow elimination of imidocarb from edible tissues in vivo.

Animals↗
PubMed1995

Alimentary lymphoma in cats: 28 cases (1988-1993).

OBJECTIVE: To evaluate response to chemotherapy in cats with alimentary lymphoma and to determine factors associated with survival time. DESIGN: Retrospective case series. ANIMALS: 28 cats with alimentary lymphoma that underwent chemotherapy. RESULTS: In all cats, the diagnosis had been established by means of cytologic or histologic examination of ultrasound-guided aspirates and biopsy specimens (18 cats), histologic examination of surgically obtained biopsy specimens (7 cats), or examination of specimens obtained endoscopically (3 cats). Clinical signs included anorexia, weight loss, vomiting, and diarrhea. Twenty-seven cats were treated with vincristine sulfate, cyclophosphamide, and prednisone; 1 was treated with chlorambucil and prednisone. Survival time ranged from 2 to 2,120 days (median, 50 days). Nine cats achieved complete remission (remission time ranged from 30 to 1,700 days; median, 213 days), 2 achieved partial remission, and 17 failed to respond to chemotherapy. Sex, FeLV status, hematocrit, serum total protein concentration, site and extent of gastrointestinal involvement, and clinical stage were not found to be associated with survival time. CLINICAL IMPLICATIONS: Cats with alimentary lymphoma are poorly responsive to treatment with vincristine, cyclophosphamide, and prednisone; however, a small subset of cats may have long survival times.

Animals↗
PubMed1995

Treatment of nephroblastoma in a juvenile dog.

A 4-month-old female Bernese Mountain Dog that was examined because of abdominal distention was found to have a nephroblastoma during exploratory laparotomy. Nephrectomy was performed, but the tumor could not be completely resected. A chemotherapeutic plan for this dog was created by adapting current recommendations for treatment of people with nephroblastoma. Chemotherapy was tolerated extremely well; however, tumor progression became evident after 15 weeks of treatment, and the dog was euthanatized. Widespread metastasis was found at necropsy. Little is known about the natural behavior of this tumor in dogs.

Animals↗
PubMed1995

Efficacy of, and toxicoses associated with, oral idarubicin administration in cats with neoplasia.

Idarubicin, a new synthetic anthracycline analogue, was administered orally to 34 cats with spontaneous tumors. The maximum tolerated dosage was determined to be 2 mg/cat/d given for 3 consecutive days every 3 weeks. Anorexia and leukopenia were found to be dose limiting in cats receiving the drug at a higher dosage. The most common toxicoses seen at the maximum tolerated dosage were leukopenia, anorexia, and vomiting; however, development of toxicoses was not found to be associated with sex, FeLV test result, tumor type, dosage, age, or weight. Idarubicin (2 mg/cat/d for 3 days, q 3 wks) was used to treat 18 cats with lymphoma in which complete remission had been achieved by administration of other chemotherapeutic agents. Median remission duration for these cats was comparable to that reported for cats treated with other protocols. We concluded that orally administered idarubicin would be useful in the treatment of cats with lymphoma.

Administration, Oral↗