317 research outputs found
Reproductive biology of Pseudotocinclus tietensis (Siluriformes: Loricariidae: Hypoptopomatinae), a threatened fish species
Pseudotocinclus tietensis is endemic to the Upper TietĂȘ River basin and classified as vulnerable. The reproductive biology of this species is still unknown, therefore, we investigated its reproductive strategy and gonad development during its annual reproductive cycle. The fish were collected throughout one year, and histology of the gonads, fecundity and oocyte diameter was conducted. Three phases of gonad maturation were found in males and females (immature, developing, and spawning capable), and the development stages of the gametes were identified within each stage. In the testes, four stages of gamete development were distinguished: spermatogonia, spermatocytes, spermatids and spermatozoa. During spermiation, the spermatozoa were released into the tubular lumen and then continued through the efferent ducts. In the ovaries, five stages of gamete development were identified: chromatin nuclear, perinucleolar, yolk vesicle formation, vitellogenic and ripe. The minimum diameter of ovulating oocytes was 297 ”m, and the absolute fecundity was 64 to 306 oocytes. Males with spermatozoa in the lobular lumen and females with vitellogenic and ripe oocytes were found throughout the year. Pseudotocinclus tietensis has asynchronous ovarian development and gametes with fertilization capacity can be eliminated throughout the annual cycle
DimensÔes do granuloma hepåtico produzido por ovos de duas linhagens geogråficas do Schistosoma mansoni, no camundongo
Association between Metabolic Disorders and Cholangiocarcinoma: Impact of a Postulated Risk Factor with Rising Incidence
Introduction and objectives: The incidence of cholangiocarcinoma (CCA) has been increasing globally. Although a concomitant increase in the incidence of metabolic disorders might suggest a causal relationship, the data are scarce. We aimed to describe the prevalence of metabolic disorders in patients with CCA and report the clinical features and outcomes. Patients and Methods: Retrospective study including patients with CCA. Patients were divided into: (1) past history of diabetes or/and overweight/obesity (âmetabolic disorder groupâ) and (2) without any of these features (ânon-metabolic-disorder groupâ). A Cox regression model was used to determine the prognostic factors. Results: 122 patients were included. In total, 36 (29.5%) had overweight/obesity, 24 (19.7%) had diabetes, and 8 (6.6%) had both. A total of 29 (23.8%) patients had resectable disease and received upfront surgery. A total of 104 (85.2%) received chemotherapy for advanced/recurrent disease. The overall survival of the cohort was 14.3 months (95% CI: 10.1â17.3). ECOG-PS 0 (p < 0.0001), resectable disease (p = 0.018) and absence of vascular invasion (p = 0.048) were independently associated with better prognosis. The âmetabolic disorder groupâ (n = 52) had a median survival of 15.5 months (95% CI 10.9â33.9) vs. 11.5 months (95% CI 8.4â16.5) in the ânon-metabolic-disorder groupâ (n = 70) (HR: 1.10; 95% CI 0.62â1.94). Patients with resectable disease in the âmetabolic groupâ had longer survival than patients in the ânon-metabolic groupâ (43.4 months (95% CI 33.9-NR) vs. 21.8 months (95% CI 8.6â26.9); HR = 0.12, 95% CI 0.03â0.59). Conclusion: Metabolic disorders are frequent among CCA patients. Underlying metabolic comorbidities may be associated with prognosis in resectable CCA. There is a need to explore the mechanism that drives CCA carcinogenesis in a metabolic background
Aspects of the granulomatous reaction in the liver of mice infected and reinfected with two different geographical strains of Schistosoma mansoni
Concurrent breast stroma sarcoma and breast carcinoma: a case report
<p>Abstract</p> <p>Introduction</p> <p>Breast cancer is one of the most important health problems in the world and affects a great number of women over the entire globe. This group of tumors rarely presents as bilateral disease and, when it does happen, normally occurs within the same histological type. We report a rare case of concurrent bilateral breast cancer with two different histology types, a breast carcinoma and a breast sarcoma, in a 42-year-old woman referred to our hospital.</p> <p>Case presentation</p> <p>A 42-year-old Caucasian woman admitted to our institute in August 1999, presented with a nodule in the left breast of 3.0 Ă 2.5 cm, and, in the right breast, one of 1.0 cm, suspected of malignancy and with a clinically negative armpit. Biopsies had revealed invasive mammary carcinoma (right breast) and sarcoma (left breast). She was submitted to bilateral modified radical mastectomy. A histological study showed an invasive mammary carcinoma degree II lobular pleomorphic type with invasion of seven of the 19 excised axillary nodes in the right breast and, in the left breast, a sarcoma of the mammary stroma, for which the immunohistochemistry study was negative for epithelial biomarkers and positive for vimentin. Later, she was submitted for chemotherapy (six cycles of 75 mg/m<sup>2 </sup>5-fluorouracil, epirubicin and cyclophosphamide) followed by radiotherapy of the thoracic wall and axillary nodes on the left. Hormone receptors were positive in the tumor of the right breast, and tamoxifen, 20 mg, was prescribed on a daily basis (five years) followed by letrozole, 2.5 mg, also daily (five years). She presented no sign of negative evolution in the last consultation.</p> <p>Conclusion</p> <p>The risk of development of bilateral breast cancer is about 1% each year within a similar histological type, but it is higher in tumors with lobular histology. In this case, the patient presented, simultaneously, two histologically distinct tumors, thus evidencing a rare situation.</p
Histiocitose de células de Langerhans: doença de Letterer-Siwe - importùncia do diagnóstico dermatológico em dois casos
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