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OBJECTIVES: Plasmablastic lymphoma (PBL) of the oral cavity is an aggressive neoplasm derived from B cell, considered to be the second more common among human immunodeficiency virus (HIV)-associated malignancies. As Epstein-Barr virus (EBV) infection has been associated with this neoplasm, the aim of the present study was to assess the presence of EBV in 11 cases of oral HIV-related PBL and investigate the controversial issue of the presence of Human herpesvirus-8 (HHV-8) in these tumors. METHODS: DNA was extracted from nine cases of HIV-associated oral lymphomas, diagnosed as PBL, and genomic material was amplified by polymerase chain reaction to verify the presence of EBV. In situ hybridization (ISH) for EBV was performed in five cases. Immunohistochemical analysis was conducted to confirm previous diagnosis and verify HHV-8 infection. RESULTS: The 11 cases had diagnosis confirmed by immunohistochemical analysis. Only nine cases presented an adequate amount of DNA for analysis, and EBV was detected in seven of them. The five cases tested for EBV viral infection by ISH showed positive signals. All 11 cases were negative for HHV-8. CONCLUSION: The presence of EBV in all cases studied favors a direct role of this virus in the development of HIV-related PBL, and this finding could be considered when dealing with HIV patients. 相似文献
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Jordão Juliana Merheb Stoliar Mariana Fajgenbaum Feiges Melo Sarah Sanches de Campos Giovana Liz Marioto de Forville Mesquita Lismary Aparecida Skare Thelma Larocca 《Lasers in medical science》2022,37(2):905-911
Lasers in Medical Science - This study refers to clinical and histologic analysis of effects on photorejuvenation after one single treatment of fractional CO2 laser with low fluence and low... 相似文献
95.
Jeffrey J. Leow William Martin-Doyle André P. Fay Toni K. Choueiri Steven L. Chang Joaquim Bellmunt 《European urology》2014
Context
The role of adjuvant chemotherapy (AC) or neoadjuvant chemotherapy (NC) remains poorly defined for the management of upper tract urothelial carcinoma (UTUC), although some studies suggest a benefit.Objective
To update the current evidence on the role of NC and AC for UTUC patients.Evidence acquisition
We searched for all studies investigating NC or AC for UTUC in Medline, Embase, the Cochrane Central Register of Controlled Trials, and abstracts from the American Society of Clinical Oncology meetings prior to February 2014. A systematic review and meta-analysis were performed.Evidence synthesis
No randomized trials investigated the role of AC for UTUC. There was one prospective study (n = 36) investigating adjuvant carboplatin–paclitaxel and nine retrospective studies, with a total of 482 patients receiving cisplatin-based or non-cisplatin–based AC after nephroureterectomy (NU) and 1300 patients receiving NU alone. Across three cisplatin-based studies, the pooled hazard ratio (HR) for overall survival (OS) was 0.43 (95% confidence interval [CI], 0.21–0.89; p = 0.023) compared with those who received surgery alone. For disease-free survival (DFS), the pooled HR across two studies was 0.49 (95% CI, 0.24–0.99; p = 0.048). Benefit was not seen for non-cisplatin–based regimens. For NC, two phase 2 trials demonstrated favorable pathologic downstaging rates, with 3-yr OS and disease-specific survival (DSS) ≤93%. Across two retrospective studies investigating NC, there was a DSS benefit, with a pooled HR of 0.41 (95% CI, 0.22–0.76; p = 0.005).Conclusions
There appears to be an OS and DFS benefit for cisplatin-based AC in UTUC. This evidence is limited by the retrospective nature of studies and their relatively small sample size. NC appears to be promising, but more trials are needed to confirm its utility.Patient summary
After a comprehensive search of studies examining the role of chemotherapy for upper tract urothelial cancer, the pooled evidence shows that cisplatin-based adjuvant chemotherapy was beneficial for prolonging survival. 相似文献96.
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Lee AD Ribeiro U Alves VA Corbett CE Nonogaki S Gama-Rodrigues J 《Arquivos de gastroenterologia》2004,41(2):114-120
BACKGROUND: Intestinal transplantation is a possible treatment for patients with short bowel syndrome, aiming the reintroduction of oral diet. However, the major obstacle in this procedure is the strong rejection. Delay in rejection diagnosis may be irreversible and lethal. AIM: To define method for early diagnosis of rejection based on the presence of interleucin-6 (IL-6) e interferon- gamma (IFN-gamma) from intestinal allograft. MATERIAL AND METHODS: Isogenic rats Brown-Norway (BN) and Lewis (LEW) were submitted to intestinal heterotopic allotransplantation and divided in two groups: LEW donor to LEW recipient isograft group (C) and BN donor to LEW recipient allograft group (Tx). According to the day of sacrifice, Tx group were subdivided in three subgroups with eight animals each as follow: Tx3--sacrificed at third postoperative day (POD), Tx5--sacrificed at fifth POD and Tx7--sacrificed at seventh POD. Eight animals from control group were subdivided in three moments according to the time of biopsy from the graft as follow: C3--biopsy at third POD; C5--biopsy at fifth POD and C7--biopsy at seventh POD. All animals from control group were sacrificed at seventh POD. Rejection parameters were compared between the control groups (C3 vs C5, C3 vs C7 and C5 vs C7, and allograft group (Tx3 vs Tx5, Tx3 vs Tx7 and Tx5 vs Tx7). The same parameters were analyzed between the control group and allograft groups (C3 vs Tx3, C5 vs Tx5 and C7 vs Tx7). RESULTS: In C group no statistical significant difference regarding the immunoexpression of the cytokines, while in Tx group, immunoexpression of IL-6 and IFN-gamma were remarkable since the fifth postoperative day. 相似文献
99.
Molecular aspects of hepatic carcinogenesis 总被引:9,自引:0,他引:9
Nita ME Alves VA Carrilho FJ Ono-Nita SK Mello ES Gama-Rodrigues JJ 《Revista do Instituto de Medicina Tropical de S?o Paulo》2002,44(1):39-48
Exogenous agents correlated with hepatocellular carcinoma (HCC) have been identified and well characterized. These agents, including the different viruses that cause chronic hepatitis and cirrhosis, can lead to regenerative nodules and dysplastic nodules/adenomatous hyperplasia. These conditions associated with several molecular alterations of hepatocyte ultimately culminate in hepatocellular carcinoma. Recently, there has been a great progress in the identification of somatic and germinative mutations that may be correlated with the development of HCC, justifying a review on the subject. Hence, the factors involved in the process of hepatic carcinogenesis, such as infection by the hepatitis B and C viruses, with a special focus in the molecular alterations described in recent years are discussed herein, pointing out areas potentially relevant for clinical development. 相似文献
100.
DnaK dependence of mutant ethanol oxidoreductases evolved for aerobic function and protective role of the chaperone against protein oxidative damage in Escherichia coli
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Echave P Esparza-Cerón MA Cabiscol E Tamarit J Ros J Membrillo-Hernández J Lin EC 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(7):4626-4631
The adhE gene of Escherichia coli encodes a multifunctional ethanol oxidoreductase (AdhE) that catalyzes successive reductions of acetyl-CoA to acetaldehyde and then to ethanol reversibly at the expense of NADH. Mutant JE52, serially selected for acquired and improved ability to grow aerobically on ethanol, synthesized an AdhE(A267T/E568K) with two amino acid substitutions that sequentially conferred improved catalytic properties and stability. Here we show that the aerobic growth ability on ethanol depends also on protection of the mutant AdhE against metal-catalyzed oxidation by the chaperone DnaK (a member of the Hsp70 family). No DnaK protection of the enzyme is evident during anaerobic growth on glucose. Synthesis of DnaK also protected E. coli from H2O2 killing under conditions when functional AdhE is not required. Our results therefore suggest that, in addition to the known role of protecting cells against heat stress, DnaK also protects numerous kinds of proteins from oxidative damage. 相似文献