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T J Bucci

Publications and source records attributed to T J Bucci.

At least 55 records · Page 3Linked to original sources
PubMed1987

A novel device for the automated administration of test compounds to laboratory animals.

A prototype instrument is described that permits efficient administration of test compounds to laboratory animals by intubation. The system integrates a balance, a computer and a volumetric dispenser. Complete animal identification, weight and dose records are kept and may be interfaced with mainframe computers. A range of doses may be delivered from a single stock solution. No carryover is evident between doses. The system is accurate, precise and rugged. The system is cost effective relative to current manual gavage techniques and offers added safety for investigators handling toxic materials.

Administration, Oral↗
PubMed1985

Profiles of induced tumors in animals.

Chemical carcinogens often induce neoplasms which differ qualitatively and quantitatively from tumors that occur spontaneously in the tissue of interest. While some experimental models have produced neoplasms indistinguishable from their spontaneous counterparts, most cause growths that are histogenetically or morphologically different, larger, more numerous, more aggressive, or of shorter latency. Induced tumors may occur in tissues where spontaneous tumors are uncommon. Cells of induced tumors may express phenotypic characteristics (e.g., membrane antigens) not present in corresponding nonneoplastic or spontaneously neoplastic cells. Conversely, some characteristics present in normal or spontaneously neoplastic cells (e.g., certain enzyme activity) may be absent in induced neoplasms. Not only may carcinogens induce tumors that differ from spontaneous ones, but the effect or a particular carcinogen may vary with the condition of its use. The species of strain, sex, and age of the host as well as the dose and route of administration are major variables. Neoplasia is one result of altered cell regulation. If we postulate a central dogma for oncogenensis, induced tumors should arise from the same molecular mechanisms that produce spontaneous tumors. Differences in "profile" reside not in the ultimate mechanism, but in the events which surround it. They result from the myriad of factors which determine the dose of proximal carcinogen to the cell's sensitive volume, together with those that modify subsequent proliferation and differentiation.

Animals↗
PubMed1984

Local carcinogenicity, rates of absorption, extent and persistence of macromolecular binding, and acute histopathological effects of N-hydroxy-1-naphthylamine and N-hydroxy-2-naphthylamine.

The N-hydroxy derivatives of 1- and 2-naphthylamine (NA) are directly carcinogenic at sites of application. In this study, the carcinogenicity of these two compounds at s.c. injection sites was compared with their relative rates of absorption, with the extent and persistence of their binding to protein, RNA, and DNA in the skin-subcutis, and with acute histopathological changes observed after local application. Male Sprague-Dawley rats were given injections of the N-hydroxy derivatives in the right rear leg at 16 mumol/dose. When administered twice weekly for 12 weeks, N-hydroxy-1-NA caused a 100% incidence (30 of 30) of poorly differentiated sarcomas at the injection site. N-Hydroxy-2-NA administered in a similar manner resulted in a low yield of tumors (7%; 2 of 30). Injection of N-hydroxy-1-NA once weekly for 12 weeks or twice weekly for 6 weeks also induced a high incidence of sarcomas (93 to 97%), but the time to tumor formation was significantly longer (p less than 0.0001) than in animals treated twice weekly for 12 weeks. The tumors were classified as malignant fibrous histiocytomas. Possible antagonistic or synergistic effects between the two compounds were also investigated. A sequential 6-week treatment with each of the N-hydroxy derivatives did not alter the expected tumor yields. However, alternating injections over 12 weeks caused a significant lengthening in the time to tumor formation (p less than 0.05). N-Hydroxy-1-NA bound covalently to protein, RNA, and DNA to a much greater extent than did N-hydroxy-2-NA. Protein binding with both derivatives decreased by 80 to 90% by 7 days after treatment. RNA binding in N-hydroxy-1-NA-treated rats markedly decreased, while N-hydroxy-2-NA-bound residues diminished only slightly. During this period, the extent of DNA binding with both derivatives remained fairly constant. When N-hydroxy-2-NA was injected 3 days after N-hydroxy-1-NA, there was a marked reduction in the apparent levels of N-hydroxy-1-NA bound to RNA and DNA. The greater tumorigenicity of N-hydroxy-1-NA versus N-hydroxy-2-NA correlated with its greater extent of macromolecular binding. Examination of acute histopathological changes occurring after single injections of N-hydroxy-1-NA and/or N-hydroxy-2-NA indicated that both compounds caused extensive necrosis in tissues at the injection site.(ABSTRACT TRUNCATED AT 400 WORDS)

1-Naphthylamine↗
PubMed1982

Technique for liver biopsy in the dromedary camel.

A technique for needle liver biopsy in camels was developed. Xylazine, 15 mg/100 kg intravenously, was used for sedation and analgesia. A 1.2 mm X 7 cm Menghini needle was introduced anteroventrally through the ninth right intercostal space, 1 cm caudal to the ninth rib and 2 cm dorsal to the costal cartilage. The needle was directed toward the contralateral olecranon with the camel in sternal recumbency. A core of liver tissue between 1 and 2 cm long was obtained from 99 of 120 attempts in 23 animals. There were no adverse effects from the procedure and histological preservation of the tissue was excellent.

Animals↗
PubMed1982

Non-invasive antromycosis: (diagnosis and treatment).

Increasing numbers of cases of chronic maxillary sinusitis are encountered which resist frequent sinus irrigation and treatment of predisposing factors. The antral washouts are of unusual consistencies and colours. The antral washouts of six cases were investigated by culture and microscopic examination and proved to contain fungal colonies. Antroscopy was a valuable asset in diagnosis. One patient had a Caldwell-Luc operation and daily irrigation through an indwelling polythene tube followed by daily instillation of clotrimazole (Canesten). The five patients who refused operation were treated by repeated bi-weekly antral washouts followed by instillation of clotrimazole. Weekly samples of antral secretions were examined by culture and microscopic examination until they were free for four consecutive weeks. We believe that frequent antral irrigation and local instillation of a broad-spectrum antimycotic drug--preferably after debridement--is the treatment of choice for antromycosis.

Adult↗
PubMed1982

Tonsillomycosis: a myco-histopathological study.

Tissues from 227 tonsillectomies, mainly in adults, were examined culturally and histopathologically for the presence of fungus. Actinomyces was demonstrated in 69 cases (30.40 per cent) by both methods. Yeasts and moulds were each isolated from 21 cases (9.25 per cent) and mixed isolates were obtained from 7 cases (3.08 per cent). There was no histopathological evidence of these organisms. Negative cultural and histopathological results were obtained in 53 cases (23.35 per cent). Chloramphenicol-resistant bacteria were cultured in 56 cases (25.11 per cent) but were seen histopathologically in only 25 cases (11.01 per cent). In all cases in which Actinomyces or bacteria were present histopathologically, a minimal tissue response indicated that these organisms were saprophytes and not primary pathogens.

Actinomyces↗
PubMed1978

The ontogenesis of calcium-binding protein in fetal rat kidney.

The presence of calcium-binding protein (CaBP) in the nucleus and cytoplasm of epithelial cells of renal tubules varies with the physiologic state. As part of a study to determine whether or not intranuclear CaBP precedes intracytoplasmic CaBP in the same cell, we used peroxidase-labeled antibody against human renal CaBP to localize CaBP in fetal rat kidney tubules. This paper reports examination of kidneys from rats on each day of gestation from the 10th to term (21 days) and on each of the first seven postnatal days. CaBP was first detected in fetal rat kidneys on the 19th gestational day. The histochemical staining reaction that revealed the CaBP was less intense than that produced in kidneys from adult animals, but its distribution was like that in adults, with some cells having no CaBP, others having it in the cytoplasm only, in the nucleus only, or in both. By the seventh postnatal day the staining reaction was similar to the adult patterns in all respects.

Animals↗
PubMed1978

Intestinal response to 1 alpha, 25-dihydroxycholecalciferol. I. RNA polymerase, alkaline phosphatase, calcium and phosphorus uptake in vitro, and in vivo calcium transport and accumulation.

The dynamics of intestinal response in rachitic chicks to 1alpha,25-dihydroxycholecalciferol were evaluated by various biochemical parameters. The following observations were made: 1. The earliest detected intestinal response to 1alpha,25-dihydroxycholecalciferol was increased in vitro calcium uptake and in vivo calcium transport, occurring by 2 h and 2.5 h respectively. 2. Increased RNA polymerase activity was observed by 4 h after 1alpha,25-dihydroxycholecalciferol treatment. 3. Calcium binding protein was detected by 5 h, but could not be detected 2.5 h after 1alpha,25-dihydroxycholecalciferol treatment. 4. Increased alkaline phosphatase activity and in vitro accumulation of inorganic phosphate were first demonstrable 6 h after 1alpha,25-dihydroxycholecalciferol treatment. 5. In vivo duodenal calcium accumulation in the mucosa was elevated after 5 h, peaked at 6.5 h, and then began to decrease at 9 h. In vitro duodenal calcium accumulation was elevated at 2 h, peaked at 12 h, and decreased to control level by 18 h. Our data emphasize the lack of correlation between the appearance of calcium binding protein or increased alkaline phosphatase activity and the transport rate of calcium across the duodenum after treatment with 1alpha,25-dihydroxycholecalciferol. The data suggest a correlation between duodenal calcium accumulation and the appearance of calcium binding protein or increased alkaline phosphatase activity.

Alkaline Phosphatase↗
PubMed1978

Immunoperoxidase localization of vitamin D dependent calcium binding protein.

Calcium binding protein (CaBP) was localized by the indirect peroxidase-labeled antibody method in chick duodenum 72 hr after administering 32.5 nmol of cholecalciferol to vitamin D-deficient chicks. CaBP was observed in cytoplasm and nuclei of absorptive cells but was absent from goblet cells. Our results are consistent with the suggested functional role for CaBP in the prevention of intracellular accumulation of calcium by preventing mitochondrial accumulation of calcium, enhancing removal of calcium from absorptive cells, and/or preventing the "leaking" of calcium into cells through the lateral borders. They are not consistent with an extracellular functional role for CaBP.

Animals↗
PubMed1975

Calcium-binding protein: its cellular localization in jejunum, kidney and pancreas.

Calcium-binding protein (CaBP) was localized with peroxidase-labeled antibody in human jejunum and kidney, and in kidney and pacreas of several animal species. The protein was associated with plasma membrane and intercellular space of jejunal absorptive cells. It was present in a specific population of renal tubule cells and in pancreatic islet cells. Immunohistochemical staining of intestinal CaBP with antibody to renal CaBP indicates structural similarity between the two proteins despite their different molecular weight.

Animals↗