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: The objective of this study was to evaluate the effects of lipopolysaccharide (LPS) endotoxemia and enteral arginine (ARG) supplementation on intestinal structural changes, enterocyte proliferation, and apoptosis in rat.', 'Male Sprague-Dawley rats, weighing 250-280 g, were divided into three experimental groups: control rats, LPS rats treated with lipopolysaccharide given ip at a dose of 10 mg/kg every 24 h (two injections), and LPS-ARG rats treated with enteral arginine given in drinking water (2%) 72 h before and following injection of LPS. Intestinal structural changes, enterocyte proliferation, and enterocyte apoptosis were determined on day 3 following the first LPS injection.', 'LPS rats demonstrated a significant decrease in bowel weight in duodenum, mucosal weight in duodenum, jejunum, and ileum, mucosal DNA and protein in jejunum and ileum, and villus height in jejunum and ileum compared to control animals. LPS rats also had a significantly lower cell proliferation index in jejunum and ileum and a higher apoptotic index in jejunum and ileum compared to control rats. LPS-ARG animals demonstrated greater duodenal bowel weight, duodenal and ileal mucosal weight, ileal mucosal DNA and protein, ileal villus height, and jejunal and ileal cell proliferation index compared to LPS animals.\Question: Does oral arginine reduce gut mucosal injury caused by lipopolysaccharide endotoxemia in rat?

SOLUTION: LPS endotoxemia impairs the integrity of the gastrointestinal mucosa in rat. Decreased cell proliferation and increased apoptosis may be considered the main mechanisms responsible for the decreased cell mass. Enteral arginine administration decreases the mucosal injury caused by lipopolysaccharide.

PROBLEM: Context: Primary pneumonic plague is a rare but often fatal form of Yersinia pestis infection that results from direct inhalation of bacteria and is potentially transmissible from person to person. We describe a case of primary pneumonic plague in a wildlife biologist who was found deceased in his residence 1 week after conducting a necropsy on a mountain lion.', "To determine cause of death, a postmortem examination was conducted, and friends and colleagues were interviewed. Physical evidence was reviewed, including specimens from the mountain lion and the biologist's medical chart, camera, and computer. Human and animal tissues were submitted for testing. Persons in close contact (within 2 meters) to the biologist after he had developed symptoms were identified and offered chemoprophylaxis.", 'The biologist conducted the necropsy in his garage without the use of personal protective equipment. Three days later, he developed fever and hemoptysis and died approximately 6 days after exposure. Gross examination showed consolidation and hemorrhagic fluid in the lungs; no buboes were noted. Plague was diagnosed presumptively by polymerase chain reaction and confirmed by culture. Tissues from the mountain lion tested positive for Y. pestis, and isolates from the biologist and mountain lion were indistinguishable by pulsed-field gel electrophoresis. Among 49 contacts who received chemoprophylaxis, none developed symptoms consistent with plague.\Question: Do primary pneumonic plague contracted from a mountain lion carcass?

SOLUTION: The biologist likely acquired pneumonic plague through inhalation of aerosols generated during postmortem examination of an infected mountain lion. Enhanced awareness of zoonotic diseases and appropriate use of personal protective equipment are needed for biologists and others who handle wildlife.

PROBLEM: Context: Vascular calcification can predict cardiovascular (CV) morbidity and mortality in patients with end-stage renal disease. We evaluated the prevalence, association factors, and outcomes of chest X-ray-detected aortic arch calcification (AoAC) in patients undergoing peritoneal dialysis (PD).', 'We included 190 patients undergoing PD (mean age, 52.6\xa0±\xa014.3\xa0years) for whom chest radiographs were available. AoAC revealed by chest X-ray was graded from 0 to 3 according to an AoAC score (AoACS). Multiple regression analyses were used to determine the factors associated with AoACS. After adjusting for age, sex, PD duration, diabetes mellitus, mean blood pressure, and history of CV disease, the association between AoAC grading and mortality were assessed using the Kaplan-Meier curve and Cox proportional hazard model.', 'Age (p\xa0<\xa00.001), PD duration (p\xa0=\xa00.004), history of CV disease (p\xa0<\xa00.001), and renal Kt/V (p\xa0=\xa00.031) were associated with AoACS. After a mean follow-up of 55.1\xa0±\xa032.1\xa0months, patients with Grade 2 (p\xa0=\xa00.011) or Grade 3 (p\xa0<\xa00.001) AoAC had higher all-cause mortality than patients with Grade 0 AoAC. In addition, patients with Grades 2 and 3 AoAC had higher CV-related mortality than those with Grades 0 and 1 AoAC (p\xa0=\xa00.013). Grade 2 [hazard ratio (HR)\xa0=\xa02.736; 95% confidence interval (CI), 1.038-7.211; p\xa0=\xa00.042] and Grade 3 AoAC (HR\xa0=\xa03.289; 95% CI, 1.156-9.359; p\xa0=\xa00.026) remained associated with all-cause mortality after adjustment. Similarly, Grades 2 and 3 AoAC (HR\xa0=\xa036.05; 95% CI, 3.494-372; p\xa0=\xa00.026) significantly correlated with CV mortality after adjustment.\Question: Does severe aortic arch calcification predict mortality in patients undergoing peritoneal dialysis?

SOLUTION:
In patients undergoing PD, CXR-detected severe AoAC was an independent risk factor for all-cause and CV mortalities.