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排序方式: 共有8126条查询结果,搜索用时 15 毫秒
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Maria Heloisa M. Shimizu Rildo A. VolpiniAna Carolina de Bragança Renata CamposDaniele Canale Talita R. SanchesLúcia Andrade Antonio C. Seguro 《Experimental gerontology》2013
The aim of this study was to evaluate the effects of N-acetylcysteine (NAC) on renal function, as well as on sodium and water transporters, in the kidneys of aged rats. Normal, 8-month-old male Wistar rats were treated (n = 6) or not (n = 6) with NAC (600 mg/L in drinking water) and followed for 16 months. At the end of the follow-up period, we determined inulin clearance, serum thiobarbituric acid reactive substances (TBARS), serum cholesterol, and urinary phosphate excretion. In addition, we performed immunohistochemical staining for p53 and for ED-1-positive cells (macrophages/monocytes), together with Western blotting of kidney tissue for NKCC2, aquaporin 2 (AQP2), urea transporter A1 (UT-A1) and Klotho protein. At baseline, the two groups were similar in terms of creatinine clearance, proteinuria, cholesterol, and TBARS. At the end of the follow-up period, NAC-treated rats presented greater inulin clearance and reduced proteinuria, as well as lower serum cholesterol, serum TBARS, and urinary phosphate excretion, in comparison with untreated rats. In addition, NAC-treated rats showed upregulated expression of NKCC2, AQP2, and UT-A1; elevated Klotho protein expression, low p53 expression, and few ED-1 positive cells. In conclusion, we attribute these beneficial effects of NAC (the significant improvements in inulin clearance and in the expression of NKCC2, AQP2, and UT-A1) to its ability to decrease oxidative stress, inhibit p53 expression, minimize kidney inflammation, and stimulate Klotho expression. 相似文献
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Silmara Ana Vendrame Leidiane de Lucca Hellen Lopes de Paula Carolina dos Santos Stein Monique Soares Paz Tatiana Frehner Kavalco 《Scandinavian journal of clinical and laboratory investigation》2013,73(7):496-501
AbstractThe purpose is to determine markers of oxidative stress related to the longer and shorter duration of labor (DOL) of pregnant women in the umbilical cord blood of neonates, not yet studied. Blood samples from the umbilical cord were collected from pregnant women with normal delivery and classified according to DOL in two groups: a group with DOL less than 310?min (n?=?33) and a group with DOL greater than or equal to 310?min (n?=?35). The oxidative stress parameters were analyzed by the quantification of thiobarbituric acid reactive substances (TBARS), nitrate/nitrite (NOx), protein thiol groups (P-SH) and non-protein (NP-SH), vitamin C and plasma iron reduction capacity (FRAP), in addition to the activity of the enzyme delta-aminolevulinate dehydratase (δ-ALA-D). The activity of the δ-ALA-D enzyme was shown to be decreased in longer DOL, however, the oxidant parameters and antioxidants were higher in the longer DOL, with the exception of NP-SH that was lower. The longer maternal DOL time is related to the alteration of δ-ALA-D enzyme activity and other parameters in neonates, suggesting an increase in the passage of maternal oxidative markers by umbilical cord blood. 相似文献
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Carolina Bernauer Y. K. Stella Man Julia C. Chisholm Elise Y. Lepicard Simon P. Robinson Janet M. Shipley 《British journal of cancer》2021,124(3):539
In tumours, hypoxia—a condition in which the demand for oxygen is higher than its availability—is well known to be associated with reduced sensitivity to radiotherapy and chemotherapy, and with immunosuppression. The consequences of hypoxia on tumour biology and patient outcomes have therefore led to the investigation of strategies that can alleviate hypoxia in cancer cells, with the aim of sensitising cells to treatments. An alternative therapeutic approach involves the design of prodrugs that are activated by hypoxic cells. Increasing evidence indicates that hypoxia is not just clinically significant in adult cancers but also in paediatric cancers. We evaluate relevant methods to assess the levels and extent of hypoxia in childhood cancers, including novel imaging strategies such as oxygen-enhanced magnetic resonance imaging (MRI). Preclinical and clinical evidence largely supports the use of hypoxia-targeting drugs in children, and we describe the critical need to identify robust predictive biomarkers for the use of such drugs in future paediatric clinical trials. Ultimately, a more personalised approach to treatment that includes targeting hypoxic tumour cells might improve outcomes in subgroups of paediatric cancer patients.Subject terms: Tumour biomarkers, Paediatric cancer, Cancer microenvironment, Cancer therapy 相似文献
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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
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Ana Carolina Vieira Costa Fernandes Távora Antonieta B Castro Maria Afonsina M Milit?o José Eduilton Gir?o Karina de Cássia Braga Ribeiro Lara Gurgel Fernandes Távora 《The Brazilian journal of infectious diseases》2008,12(1):75-79
This study was designed to describe the epidemiology and risk factors for nosocomial infection (NI) in a Brazilian neonatal intensive care unit (NICU). This study was a retrospective cohort from January to December, 2003. All neonates admitted to the NICU. Infection surveillance was conducted according to the NNIS, CDC. Chi-square test and logistic regression model were performed for statistical analyses. The study was conducted at a public, tertiary referral NICU of a teaching hospital in the Northeast of Brazil. A total of 948 medical records were reviewed. Overall NI incidence rate was 34%. The main neonatal NI was bloodstream infection (68.1%), with clinical sepsis accounting for 47.2%, and pneumonia was the second most common NI (8.6%). Multivariate analysis identified seven independent risk factors for NIs: birth weight, exposure to parenteral nutrition, percutaneous catheter, central venous catheter or mechanical ventilation, abruptio placentae and mother's sexually transmitted disease (STD). Neonates from mothers with STD or abruptio placentae, those weighing less than 1,500 g at birth or those who used invasive devices were at increased risk for acquiring NI. 相似文献