TASK DEFINITION: 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.
PROBLEM: Context: In HIV patients, disorders in glucose metabolism seem to be side effects of highly active antiretroviral therapy (HAART) which may be favoured by obesity, abdominal fat accumulation and familial disposition for diabetes mellitus (DM). The aim of our study was to identify patients at high risk for abnormalities in glucose metabolism taking into account HAART, familial disposition for DM and anthropometric parameters.', 'Plasma glucose, insulin, c-peptide and insulin resistance (homeostasis model assessment, HOMA) were determined in 44 HIV patients [16 without HAART, 19 with protease inhibitors (PI), 9 without PI (non-PI)] and in 11 healthy subjects. Glucose tolerance was determined by standard procedures. Body mass index (BMI), triceps skin fold thickness and waist circumference were measured and the waist-to-hip-ratio was calculated. Familial disposition for DM was assessed by questionnaire.', 'Impaired fasting glucose was observed in 28% of HAART-treated patients (21% with PI, 7% non-PI), in 13% of HAART-naive but none in healthy controls. 58% of PI, 44% of non-PI, 38% of HAART-naive and none of healthy controls had a HOMA-index > 2.5 which indicates insulin resistance. HAART-treated patients had significantly higher fasting glucose levels (PI: 97 +/- 11 mg/dL, p = 0.048; non-PI: 109 +/- 58 mg/dL, p = 0.009) compared to healthy controls (72 +/- 8 mg/dL). HOMA-Index was higher in PI treated patients (3.74 +/- 3.08) than in HIV negative controls (0.95 +/- 0.28, p = 0.018). The duration of HAART (p = 0.045), overweight and familial disposition for DM (p = 0.017) significantly affected fasting glucose among PI users. Waist circumference affected c-peptide (p = 0.046) concentration in these patients.\Question: Are overweight HIV patients with abdominal fat distribution treated with protease inhibitors at high risk for abnormalities in glucose metabolism - a reason for glycemic control?

SOLUTION: HIV patients on long-term PI therapy with overweight and familial disposition for DM are at high risk to develop abnormalities of glucose metabolism. Thus, measurements of HOMA-Index, BMI and waist circumference should be routinely done especially in PI medicated patients.

PROBLEM: Context: RNA editing is the process whereby an RNA sequence is modified from the sequence of the corresponding DNA template. In the mitochondria of land plants, some cytidines are converted to uridines before translation. Despite substantial study, the molecular biological mechanism by which C-to-U RNA editing proceeds remains relatively obscure, although several experimental studies have implicated a role for cis-recognition. A highly non-random distribution of nucleotides is observed in the immediate vicinity of edited sites (within 20 nucleotides 5' and 3'), but no precise consensus motif has been identified.", "Data for analysis were derived from the the complete mitochondrial genomes of Arabidopsis thaliana, Brassica napus, and Oryza sativa; additionally, a combined data set of observations across all three genomes was generated. We selected datasets based on the 20 nucleotides 5' and the 20 nucleotides 3' of edited sites and an equivalently sized and appropriately constructed null-set of non-edited sites. We used tree-based statistical methods and random forests to generate models of C-to-U RNA editing based on the nucleotides surrounding the edited/non-edited sites and on the estimated folding energies of those regions. Tree-based statistical methods based on primary sequence data surrounding edited/non-edited sites and estimates of free energy of folding yield models with optimistic re-substitution-based estimates of approximately 0.71 accuracy, approximately 0.64 sensitivity, and approximately 0.88 specificity. Random forest analysis yielded better models and more exact performance estimates with approximately 0.74 accuracy, approximately 0.72 sensitivity, and approximately 0.81 specificity for the combined observations.\Question: Do simple statistical models predict C-to-U edited sites in plant mitochondrial RNA?

SOLUTION: Simple models do moderately well in predicting which cytidines will be edited to uridines, and provide the first quantitative predictive models for RNA edited sites in plant mitochondria. Our analysis shows that the identity of the nucleotide -1 to the edited C and the estimated free energy of folding for a 41 nt region surrounding the edited C are the most important variables that distinguish most edited from non-edited sites. However, the results suggest that primary sequence data and simple free energy of folding calculations alone are insufficient to make highly accurate predictions.

PROBLEM: 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?

SOLUTION:
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.