Incidents Malignant Neoplasias Maxillofacial Area

Cancer is regarded as abnormal cellular multiplication; it is not controlled by the organism, and its cells present a differentiated DNA. Initially, the disease does not show clinical signs, but it can be diagnosed by laboratory examinations. When tumors are present in the maxillofacial area.. the carrier can lose structures in this area, resulting to the carrier's social environment exclusion. This article aims to show incidences and causes of malignant neoplasias in the maxillofacial area.

Detection of numerical chromosome anomalies in interphase cells of benign and malignant thyroid lesions using fluorescence in situ hybridization

Benign and malignant thyroid tumors constitute a wide range of neoplasias showing recurrent chromosome abnormalities. In an attempt to characterize specific numerical chromosome abnormalities in thyroid tissues, We present here the findings from a study of archival samples depicted by 10 malignant tumors, 30 benign lesions, and 10 normal thyroid tissues. Fluorescence in situ hybridization was performed on noncultured samples using biotinylated centromere-specific probes for chromosomes 7, 10, and 17. Trisomy or tetrasomy 7 were present in 19 benign and in 7 malignant tumors. Trisomy 10 or 17 were observed in 18 adenomas or goiters and in 9 carcinomas, and monosomy 17 was seen in 2 carcinomas. Our findings suggest that such abnormalities are an in vivo phenomenon and may be important in the neoplastic proliferation of thyroid gland. (C) Elsevier B.V., 2000. All rights reserved.

Anatomy of smooth muscle cells in nonmalignant and malignant human prostate tissue

Differently graded areas of human prostate adenocarcinoma were examined after Masson's trichrome staining or immunohistochemistry for smooth muscle alpha-actin, type IV collagen and laminin. In addition, the ultrastructure of the prostatic smooth muscle cells (SMC) during glandular proliferation and epithelial invasion in selected tumors was studied. The SMC formed a thick layer below the epithelial structures in unaffected areas and were closely associated with each other in homotypic interactions. As the tumor grade increased, the SMC gradually lost interactions with each other and became atrophic. With the growth of the epithelial compartment, the SMC initially segregated to the tumor periphery and the intercellular spaces increased. In high grade tumors, the epithelial cancer cells invaded the spaces between the SMC. Immunohistochemical analysis of the basal membrane revealed increased disruption of the usually thick basal membrane, which became thinner and faintly stained with each of the antibodies used. We conclude that most SMC become atrophic following epithelial invasion in human tumors and that degradation of the basal membrane is an important factor in this process. At the ultrastructural level, different SMC phenotypes occur in prostatic tissues during epithelial invasion. Interconversion between these phenotypes is suggested and a probable relationship among them is proposed.

Malignant ameloblastoma metastasis to the lung: a case report

Ameloblastoma is an odontogenic tumor, usually benign, which rarely metastasizes to distant organs. The case of a 27-year-old white woman is described, who presented a metastatic pulmonary ameloblastoma 7 years after the removal of a mandibular ameloblastoma. She presented no pulmonary symptoms, but a lung nodule was found in a chest x-ray during a routine check-up for job admission. Computed tomography (CT) revealed a 2-cm well-defined solitary round nodule without calcifications, leading to the hypothesis of a metastatic tumor. Clinical and CT investigation confirmed no ameloblastoma recurrence in the jaw and no other primary tumor. The diagnosis of metastatic ameloblastoma was confirmed by microscopic evaluation of the pulmonary nodule.

POSSIBLE MECHANISMS FOR REDUCTION OF CIRCULATING CONCENTRATIONS OF PROGESTERONE BY INTERFERON-ALPHA IN COWS - EFFECTS ON HYPERTHERMIA, LUTEAL CELLS, METABOLISM OF PROGESTERONE AND SECRETION OF LH

Experiments were performed to determine the mechanism by which recombinant bovine interferon-alpha(I)1 (rbIFN-alpha) causes an acute reduction in plasma concentrations of progesterone. In experiment 1, administration of a prostaglandin synthesis inhibitor blocked rbIFN-alpha-induced hyperthermia but did not prevent the decline in plasma concentrations of progesterone. The decline in progesterone concentrations caused by rbIFN-alpha was, therefore, not a direct consequence of the associated hyperthermia or of pathways mediated through prostaglandin synthesis. It is also unlikely that rbIFN-alpha acts to increase the clearance of progesterone since injection of rbIFN-alpha did not decrease plasma concentrations of progesterone in ovariectomized cows given an intravaginal implant of progesterone (experiment 2). In experiment 3, rbIFN-alpha did not affect basal and LH-induced release of progesterone from cultured luteal slices, indicating that rbIFN-alpha is unlikely to affect luteal function directly. Injection of rbIFN-alpha did, however, cause a decrease in plasma concentrations of LH in ovariectomized cows (experiment 4) that coincided temporally with the decrease in progesterone concentrations seen in cows having a functional corpus luteum. The present results strongly suggest that rbIFN-alpha acts to reduce secretion of progesterone by interfering with pituitary support for luteal synthesis of progesterone. The finding that rbIFN-alpha can inhibit LH secretion implies that interferon-alpha molecules should be considered among the cytokines that can regulate hypothalamic or pituitary function.

Effect of indomethacin on hyperthermia induced by heat stress in broiler chickens

An investigation was carried out to verify whether the heat stress hyperthermia response of broilers is prostaglandin-dependent. Male broiler chickens of the Hubbard-Petterson strain, aged 35-49 days, were used. Chickens were injected with indomethacin (1 mg/kg intraperitoneally) 15 min before or 2 h after heat exposure (at 35 degrees C for 4 h), and rectal temperature was measured before injection and up to 4 h thereafter. Birds were separated into two groups with and without access to water during heat stress. The increase in rectal temperature was lower (P<0.05) in birds with access to drinking water during heat exposure. All birds injected with indomethacin exhibited an increase in rectal temperature, irrespective of whether indomethacin was administered before or in the course of the rise in temperature. The results revealed that the increase in rectal temperature during heat exposure is not prostaglandin-dependent, and that the use of cyclooxigenase inhibitors is not recommended to attenuate heat stress hyperthermia in broiler chickens.

Malignant catarrhal fever-like lesions associated with ovine herpesvirus-2 infection in young calves (Bos indicus): a case report

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Conventional and Doppler ultrasound for the differentiation of benign and malignant canine mammary tumours

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)