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1.
Pyroglutamyl, proline-rich oligopeptides, classically referred to as bradykinin-potentiating peptides (BPPs) are found in Bothrops jararaca venom, and are naturally occurring inhibitors of the somatic angiotensin-converting enzyme (ACE). The chemical and pharmacological properties of these peptides were essential for the development of captopril, the first active site directed inhibitor of ACE, currently used to treat human hypertension. ACE is a complex ectoenzyme of the vascular endothelium, possessing two catalytic sites, performing diverse specific roles. Recent advances concerning novel features of BPPs revealed that they might still contribute to a better understanding of the cardiovascular physiology and pathology. The molecular biology of the BPPs revealed that they are part of two distinct C-type natriuretic peptide precursors found in the venom gland and the brain of B. jararaca, each containing seven BPPs. In situ hybridization studies detected the presence of the corresponding mRNA precursor in snake brain regions correlated with neuroendocrine functions, such as the ventro-medial hypothalamus, the paraventricular nuclei, the paraventricular organ, and the subcommissural organ. In this article we discuss the large variety of homologous BPPs in B. jararaca venom and brain, its significance, and whether the BPPs could represent novel endogenous neuropeptides. 相似文献
2.
Third ventricular primary cerebral neuroblastoma. Electron-microscopic and immunohistochemical study
A case of third ventricular primary cerebral neuroblastoma with secondary hydrocephalus is reported. Light microscopy showed a cell pattern that resembled either ependymoma or oligodendroglioma. The tumor was confirmed to be neuroblastoma by electron microscopy and immunohistochemistry. Immunoperoxidase staining was positive for neuron-specific enolase and negative for glial fibrillary acidic protein. 相似文献
3.
T. P. Poon M. Behbahani I. Matoso B. Kim 《Journal of the National Medical Association》1994,86(7):550-552
A pineal mass in a patient with acquired immunodeficiency syndrome (AIDS) is reported. Computed tomography (CT) scan revealed a nodular mass in the pineal region with foci of calcification and obstruction of the aqueduct mimicking a pineal tumor. At autopsy, the brain revealed a well-circumscribed lesion with central necrosis in the pineal region suggestive of toxoplasma and involving the periaqueductal area. Susceptibility of a patient with AIDS to opportunistic infections should be considered. 相似文献
4.
Saidy Vásconez Noguera Evelyn Patrícia Sánchez Espinoza Marina Farrel Côrtes Izabel Cristina Vilela Oshiro Fernanda de Sousa Spadão Laura Maria Brasileiro Brandão Ana Natiele da Silva Barros Sibeli Costa Bianca Leal de Almeida Paula Gemignani Soriano Alessandra Grassi Salles Mirian Elizabete Marques Escorcio Cristina Madeira Barretti Fernanda Spadotto Baptista Glaura Souza Alvarenga Igor Marinho Leila Suemi Harima Letaif Ho Ye Li Silvia Figueiredo Costa 《American journal of infection control》2021,49(4):512-515
5.
6.
Ana Paula H. Yokoyama Silvano Wendel Carolina Bonet-Bub Roberta M. Fachini Ana Paula F. Dametto Fernando Blumm Valeria F. Dutra Gabriela T. P. Candelaria Araci M. Sakashita Rafael Rahal Guaragna Machado Rita Fontão-Wendel Nelson Hamerschlak Ruth Achkar Murillo Santucci Cesar Assunção Patrícia Scuracchio Victor Nudelman Laerte Pastore João R. R. Pinho Mirian Dal Ben Roberto Kalil Filho Alexandre R. Marra Mariane T. Amano Esper G. Kallás Alfredo Salim Helito Carlos Roberto Ribeiro de Carvalho Danielle Bastos Araujo Edison Luiz Durigon Anamaria A. Camargo Luiz V. Rizzo Luiz F. L. Reis Jose M. Kutner 《Transfusion》2021,61(8):2295-2306
7.
Joo V Nani Caroline Dal Mas Camila M Yonamine Vanessa K Ota Cristiano Noto Sintia I Belangero Jair J Mari Rodrigo Bressan Quirino Cordeiro Ary Gadelha Mirian A F Hayashi 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2020,23(11):721
BackgroundOur previous studies showed increased angiotensin I-converting enzyme (ACE) activity in chronic schizophrenia patients compared with healthy control (HC) volunteers, and the relevance of combining ACE genotype and activity for predicting schizophrenia was suggested.MethodsACE activity was measured in plasma of ACE insertion/deletion (I/D) genotyped HC volunteers (n = 53) and antipsychotic-naïve first-episode psychosis (FEP) patients (n = 45) assessed at baseline (FEB-B) and also after 2 months (FEP-2M) of treatment with the atypical antipsychotic risperidone.ResultsACE activity measurements showed significant differences among HC, FEP-B, and FEP-2M groups (F = 5.356, df = 2, P = .005) as well as between HC and FEP-2M (post-hoc Tukey’s multiple comparisons test, P = .004). No correlation was observed for ACE activity increases and symptom severity reductions in FEP as assessed by total Positive and Negative Syndrome Scale (r = −0.131, P = .434). FEP subgrouped by ACE I/D genotype showed significant ACE activity increases, mainly in the DD genotype subgroup. No correlation between ACE activity and age was observed in FEP or HC groups separately (r = 0.210, P = .392), but ACE activity level differences observed between these groups were influenced by age.ConclusionsThe importance of measuring the ACE activity in blood plasma, associated with ACE I/D genotyping to support the follow-up of FEP patients, did not show correlation with general symptom amelioration in the present study. However, new insights into the influence of age and I/D genotype for ACE activity changes in FEP individuals upon treatment was demonstrated. 相似文献
8.
Monica Pires Ribeiro Sergio Augusto Lopes de Souza Flavia Paiva Proen?a Lobo Lopes Paulo Henrique Rosado-de-Castro Lea Mirian Barbosa da Fonseca Bianca Gutfilen 《Clinics (S?o Paulo, Brazil)》2013,68(3):283-289
OBJECTIVE:
Mammography has been established as the gold standard for the detection of breast cancer, and imaging techniques such as ultrasonography, magnetic resonance imaging, scintigraphy and positron emission tomography may be useful to improve its sensitivity and specificity. The objective of this study with breast scintigraphy was to evaluate the uptake of 99mTc-thymine in mammary lesions.METHODS:
A total of 45 patients were included in this study. Thirty-three patients (73%) were subjected to surgery or percutaneous biopsy, providing histopathological data. The other 12 patients who remained under surveillance received clinical examinations and biannual mammography with a normal follow-up of at least three years, the data from which were used for comparison with the scintimammography results.RESULTS:
The majority of patients (64.4%) had clinically impalpable lesions with a mammogram diagnosis of microcalcifications, impalpable nodules, or focal asymmetry. Of the studied lesions, 87% were smaller or equal to 20 mm in diameter, and 22% had malignant histopathological findings. Scintigraphy with 99mTc-thymine had a sensitivity of 70%, a specificity of 85.7%, positive and negative predictive values of 58.3% and 90.9%, respectively, and an accuracy of 82.2%.CONCLUSIONS:
The results of this study are consistent with those previously reported by other authors. The good specificity and high negative predictive value of this technique and the absence of uptake in the heart indicate that it may be a promising complementary method in clinical practice and that it may contribute to reducing unnecessary benign biopsies. 相似文献9.