In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.

Context: Circulation on blood extracorporeally through plastic tubing activates several pathways including systemic inflammation and oxidative stress. These phenomena are suspected to participate to neurological and cardiovascular side effects observed in the patients under cardiopulmonary bypass (CPB). A direct relationship, in diabetic patients, between hyperglycemia and morbidity and mortality has been established. However, it is still unclear whether perioperative hyperglycemia has a direct effect on adverse events in cardiac surgery. The purpose of this study was to determine the influence of hyperglycemia on inflammation and oxidative stress in patients under CPB during cardiac surgery.', 'Control patients (n=17) and diabetic (type 2) patients (n=13) were included in this study. Blood samples were drawn before, during and after the CPB. Oxidative stress was evaluated in the plasma by direct and indirect approaches. Direct detection of ascorbyl radicals was assessed by electron spin resonance spectroscopy. An index: ascorbyl radical/vitamin C ratio is an indicator of the degree of oxidative stress taking place in the plasma. Oxygen radical absorbing capacity (ORAC) values were used as measurement of antioxidant capacity of the plasma. To determine inflammation profile of patients, we measure the evolution of plasma concentration of interleukin 8 (IL-8).', 'During cross clamping and post-CPB, the index ascorbyl radical/vitamin C is increased; the value of the index is more significant in diabetic patients. Concomitantly, ORAC values decreased in all the patients during cross clamping (p<0.05). Results concerning inflammatory index showed that IL-8 levels increased during the CPB.\Question: Is [ Oxidative stress exacerbated in diabetic patients during cardiopulmonary bypass ]?
In conclusion, the current study indicates that a systemic oxidative stress occurs during CPB and post-CPB periods and that in patients with type 2 diabetes mellitus, the systemic oxidative stress was increased.

Context: Pandemic strains of HIV-1 (group M) encode a total of nine structural (gag, pol, env), regulatory (rev, tat) and accessory (vif, vpr, vpu, nef) genes. However, some subtype A and C viruses exhibit an unusual gene arrangement in which the first exon of rev (rev1) and the vpu gene are placed in the same open reading frame. Although this rev1-vpu gene fusion is present in a considerable fraction of HIV-1 strains, its functional significance is unknown.', 'Examining infectious molecular clones (IMCs) of HIV-1 that encode the rev1-vpu polymorphism, we show that a fusion protein is expressed in infected cells. Due to the splicing pattern of viral mRNA, however, these same IMCs also express a regular Vpu protein, which is produced at much higher levels. To investigate the function of the fusion gene, we characterized isogenic IMC pairs differing only in their ability to express a Rev1-Vpu protein. Analysis in transfected HEK293T and infected CD4+ T cells showed that all of these viruses were equally active in known Vpu functions, such as down-modulation of CD4 or counteraction of tetherin. Furthermore, the polymorphism did not affect Vpu-mediated inhibition of NF-B activation or Rev-dependent nuclear export of incompletely spliced viral mRNAs. There was also no evidence for enhanced replication of Rev1-Vpu expressing viruses in primary PBMCs or ex vivo infected human lymphoid tissues. Finally, the frequency of HIV-1 quasispecies members that encoded a rev1-vpu fusion gene did not change in HIV-1 infected individuals over time.\Question: Does a Naturally Occurring rev1-vpu Fusion Gene Confer a Fitness Advantage to HIV-1?
Expression of a rev1-vpu fusion gene does not affect regular Rev and Vpu functions or alter HIV-1 replication in primary target cells. Since there is no evidence for increased replication fitness of rev1-vpu encoding viruses, this polymorphism likely emerged in the context of other mutations within and/or outside the rev1-vpu intergenic region, and may have a neutral phenotype.

Context: To investigate the potential efficacy of real-time contrast-enhanced power Doppler sonography in the differentiation of benign and malignant adnexal masses in a pilot study.', 'Before surgical treatment, adnexal masses were prospectively evaluated with power Doppler sonography before and after injection of a contrast agent. Real-time postinjection sequences were computerized with time-intensity analysis software to determine an enhancement curve and contrast parameters. The intraobserver and interobserver reproducibilities of these criteria were assessed on a subsample. These contrast parameters were compared between benign and malignant tumors using logistic regression. Sensitivity and specificity were used to compare contrast parameters with sonographic and Doppler variables.', 'Ninety-nine women were included, for a total of 101 adnexal masses. There were 23 cases of ovarian malignancies and 78 benign adnexal lesions. Our procedure had excellent intraobserver and interobserver reproducibility, with an average intraclass correlation coefficient of 0.92. The time before enhancement and intensity ratio did not reliably differentiate between the benign and malignant masses. Washout times and areas under the curves were significantly greater in ovarian malignancies than in other benign tumors (P < .001), leading to sensitivity estimates between 96% and 100% and specificity estimates between 83 and 98%. Contrast parameters had slightly higher sensitivity and slightly lower specificity when compared with transvaginal sonographic variables of the resistive index and serum cancer antigen 125 levels.\Question: Does contrast-enhanced sonography help in discrimination of benign from malignant adnexal masses?
Contrast-enhanced power Doppler imaging may easily and precisely discriminate benign from malignant adnexal lesions. Larger studies are needed to determine the appropriate use and benefits of this new procedure.