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101.
102.
K. L. Ferrazzo M. M. Neto E. dos Santos D. dos Santos Pinto S. O. M. de Sousa 《Journal of oral pathology & medicine》2009,38(9):701-707
Background: Galectin-3 has been implicated in tumor progression of some malignancies as thyroid, prostate, and salivary gland tumors. Recently, it has been suggested that this protein may be an important mediator of the β-catenin/Wnt pathway. Moreover, nuclear galectin-3 expression has been implicated in cell proliferation, promoting cyclin D1 activation. Thus, the present study aimed to correlate galectin-3 expression with β-catenin and cyclin D1 expressions in adenoid cystic carcinoma (ACC) and in polymorphous low-grade adenocarcinoma (PLGA).
Methods: Fifteen formalin-fixed paraffin-embedded cases of each tumor were retrieved from the files of the Surgical Oral Pathology Service at the University of São Paulo and the proteins were analyzed by immunohistochemistry.
Results: Adenoid cystic carcinoma showed galectin-3 immunostaining mainly in the nuclei, while PLGA revealed a positive mostly cytoplasmic reaction to galectin-3 in the largest part of tumor cells. Both tumors showed intense cytoplasmic/nuclear staining for β-catenin in majority of cases. Cyclin D1 immunoreactivity was not detected in 14/15 PLGA and showed specific nuclear staining in 10/15 cases of ACC in more than 5% of the neoplastic cells. Cyclin D1 expression was correlated with cytoplasmic and nuclear galectin-3 expression in ACC ( P < 0.05).
Conclusions: These results suggest that in ACC galectin-3 may play a role in cellular proliferation through cyclin D1 activation. In addition, nuclear expression of galectin-3 in ACC may be related to a more aggressive behavior of this lesion. Although β-catenin seems to play a role in carcinogenesis in both lesions, it seems that it does not bind to galectin-3 for cyclin D1 stimulation. 相似文献
Methods: Fifteen formalin-fixed paraffin-embedded cases of each tumor were retrieved from the files of the Surgical Oral Pathology Service at the University of São Paulo and the proteins were analyzed by immunohistochemistry.
Results: Adenoid cystic carcinoma showed galectin-3 immunostaining mainly in the nuclei, while PLGA revealed a positive mostly cytoplasmic reaction to galectin-3 in the largest part of tumor cells. Both tumors showed intense cytoplasmic/nuclear staining for β-catenin in majority of cases. Cyclin D1 immunoreactivity was not detected in 14/15 PLGA and showed specific nuclear staining in 10/15 cases of ACC in more than 5% of the neoplastic cells. Cyclin D1 expression was correlated with cytoplasmic and nuclear galectin-3 expression in ACC ( P < 0.05).
Conclusions: These results suggest that in ACC galectin-3 may play a role in cellular proliferation through cyclin D1 activation. In addition, nuclear expression of galectin-3 in ACC may be related to a more aggressive behavior of this lesion. Although β-catenin seems to play a role in carcinogenesis in both lesions, it seems that it does not bind to galectin-3 for cyclin D1 stimulation. 相似文献
103.
Lacativa PG Donangelo I Wagman MB Sieiro Neto L Caldas CR Violante AH Lima RJ Vaisman M 《Arquivos brasileiros de endocrinologia e metabologia》2004,48(2):318-323
Opportunistic infections in endogenous Cushing's syndrome are associated with severe cortisol excess and carry a high mortality. Pulmonary cryptococcosis is one of these opportunistic infections and can mimic a lung neoplasm, therefore making its diagnosis difficult. We report a case of a young male with ACTH-dependent Cushing's syndrome and severe hypercortisolism. The patient achieved cure after the transfenoidal surgery, but developed a febrile state. A chest computed tomography showed a pulmonary nodule that did not change in serial chest radiographs. Diagnosis of tuberculosis, fungal and bacterial infections were inconclusive, so the hypothesis of lung neoplasm became more probable. The necropsy, however, disclosed a pseudotumoral cryptococcosis. Opportunistic infections, like Cryptococcus neoformans, should be considered in patients with Cushing's syndrome and a pulmonary infiltrate. 相似文献
104.
Brown adipose tissue (BAT) is involved in rat and mice thermoregulation, and heat produced by BAT depends on the concerted action of thyroid hormones and catecholamines. Little is known about cold-induced thermogenesis in mammals that have little or no BAT, such as rabbits. In these animals, thermogenesis primarily occurs in skeletal muscle. In this work, we have studied the effect of cold acclimation (4 C for 10 d) in normal and hypothyroid rabbits. It is known that hypothyroid rats die after a few hours of cold exposure. We now show that, different from rats, hypothyroid rabbits sustain their body temperature and survive after 10 d cold exposure. When compared with rabbits kept at room temperature, the muscles of cold-exposed rabbits showed a dark red color characteristic of oxidative muscle fibers. According to this pattern, we observed that in both normal and hypothyroid rabbits, cold exposure promotes an increase in oxygen consumption by skeletal muscle mitochondria. Moreover, in red muscle, cold acclimation induces an increase in the expression and activity of sarcoplasmic reticulum Ca(2+) ATPase isoform 1 (SERCA1), one of the muscle enzymes involved in heat production. We conclude that rabbit cold tolerance is probably related to increased muscle oxidative metabolism and heat production by SERCA1 and that these changes are not completely dependent on normal thyroid function. 相似文献
105.
106.
V Amato Neto A A Moreira G M Ferreira S A do Nascimento L Matsubara R Campos P L Pinto 《Revista do Instituto de Medicina Tropical de S?o Paulo》1990,32(3):185-188
With the objective of knowing adequately the spectrum of activity of albendazole against intestinal helminthiases, we made observations regarding hymenolepiasis caused by Hymenolepis nana. Two series of investigations were carried out: a) treatment of mice with single doses of either 25 or 50 mg/kg, repeated after ten days, using as controls animals treated with 25 mg/kg of praziquantel or not treated with any antiparasitic drugs; b) treatment of adults and children with 400 mg daily for three consecutive days, repeated after ten days. 相似文献
107.
Valim V Oliveira LM Suda AL Silva LE Faro M Neto TL Feldman D Natour J 《The Journal of rheumatology》2002,29(2):353-357
OBJECTIVE: To compare maximum oxygen uptake and anaerobic threshold in patients with fibromyalgia (FM) and healthy sedentary controls matched by sex, age, weight, and body mass index. METHODS: Fifty women with FM aged 18-60 years and 50 healthy sedentary controls were studied. All were submitted to a maximum treadmill incremental test. Expired gas, ventilatory anaerobic threshold, and maximum oxygen uptake (VO2max) were evaluated. The influence of FM on quality of life was evaluated by questionnaires: the Fibromyalgia Impact Questionnaire and the Medical Outcomes Study Short-Form (SF-36). RESULTS: In patients with FM, the anaerobic threshold and peak oxygen uptake were significantly reduced. Maximum heartbeat rate was significantly lower in FM, indicating submaximum effort. Linear regression data showed a correlation between peak VO2 and the "Role-physical" domain of the SF-36. No such correlations were noted with anaerobic threshold. CONCLUSION: These results confirm the hypothesis of lower physical fitness in patients with FM. Considering that patients with FM do not achieve a maximum effort, ventilatory anaerobic threshold should be considered as a better fitness index than VO2max. 相似文献
108.
Gisele Alborghetti Nai Denis Aloísio Lopes Medina Cesar Alberto Talavera Martelli Mayla Silva Cayres de Oliveira Maria Júlia Schadeck Portelinha Bruno Carvalho Henriques Isadora Delfino Caldeira Mrcia de Carvalho Almeida Lizziane Kretli Winkelstroter Eller Fausto Viterbo de Oliveira Neto Maringela Esther Alencar Marques 《Medicine》2021,100(13)
Surface treatment of medical devices may be a way of avoiding the need for replacement of these devices and the comorbidities associated with infection. The aim of this study was to evaluate whether pre- and postcontamination washing of 2 prostheses with different textures can decrease bacterial contamination.The following microorganisms were evaluated: Staphylococcus aureus, Staphylococcus epidermidis, Proteus mirabilis and Enterococcus faecalis. Silicone and expanded polytetrafluoroethylene vascular prostheses were used and divided into 3 groups: prostheses contaminated; prostheses contaminated and treated before contamination; and prostheses contaminated and treated after contamination. Treatments were performed with antibiotic solution, chlorhexidine and lidocaine. After one week of incubation, the prostheses were sown in culture medium, which was incubated for 48 hours. The area of colony formation was evaluated by fractal dimension, an image analysis tool.The antibiotic solution inhibited the growth of S epidermidis and chlorhexidine decrease in 53% the colonization density for S aureus in for both prostheses in the pre-washing. In postcontamination washing, the antibiotic solution inhibited the growth of all bacteria evaluated; there was a 60% decrease in the colonization density of S aureus and absence of colonization for E faecalis with chlorhexidine; and lidocaine inhibited the growth of S aureus in both prostheses.Antibiotic solution showed the highest efficiency in inhibiting bacterial growth, especially for S epidermidis, in both washings. Lidocaine was able to reduce colonization by S aureus in post-contamination washing, showing that it can be used as an alternative adjuvant treatment in these cases. 相似文献
109.
110.