University of Tennessee Health Science Center

About: University of Tennessee Health Science Center is a education organization based out in Memphis, Tennessee, United States. It is known for research contribution in the topics: Population & Medicine. The organization has 15716 authors who have published 26884 publications receiving 1176697 citations.

NIX is required for programmed mitochondrial clearance during reticulocyte maturation

Abstract: The regulated clearance of mitochondria is a well recognized but poorly understood aspect of cellular homeostasis, and defects in this process have been linked to aging, degenerative diseases, and cancer. Mitochondria are recycled through an autophagy-related process, and reticulocytes, which completely eliminate their mitochondria during maturation, provide a physiological model to study this phenomenon. Here, we show that mitochondrial clearance in reticulocytes requires the BCL2-related protein NIX (BNIP3L). Mitochondrial clearance does not require BAX, BAK, BCL-XL, BIM, or PUMA, indicating that NIX does not function through established proapoptotic pathways. Similarly, NIX is not required for the induction of autophagy during terminal erythroid differentiation. NIX is required for the selective elimination of mitochondria, however, because mitochondrial clearance, in the absence of NIX, is arrested at the stage of mitochondrial incorporation into autophagosomes and autophagosome maturation. These results yield insight into the mechanism of mitochondrial clearance in higher eukaryotes. Furthermore, they show a BAX- and BAK-independent role for a BCL2-related protein in development.

Guidelines on nicotine dose selection for in vivo research

Abstract: Rationale This review provides insight for the judicious selection of nicotine dose ranges and routes of administration for in vivo studies. The literature is replete with reports in which a dosaging regimen chosen for a specific nicotine-mediated response was suboptimal for the species used. In many cases, such discrepancies could be attributed to the complex variables comprising species-specific in vivo responses to acute or chronic nicotine exposure.

Pancreatic adenocarcinoma, version 2.2017: Clinical practice guidelines in Oncology

Abstract: Ductal adenocarcinoma and its variants account for most pancreatic malignancies. High-quality multiphase imaging can help to preoperatively distinguish between patients eligible for resection with curative intent and those with unresectable disease. Systemic therapy is used in the neoadjuvant or adjuvant pancreatic cancer setting, as well as in the management of locally advanced unresectable and metastatic disease. Clinical trials are critical for making progress in treatment of pancreatic cancer. The NCCN Guidelines for Pancreatic Adenocarcinoma focus on diagnosis and treatment with systemic therapy, radiation therapy, and surgical resection.

Efficacy and Safety of Monoclonal Antibody to Human Tumor Necrosis Factor α in Patients With Sepsis Syndrome: A Randomized, Controlled, Double-blind, Multicenter Clinical Trial

Abstract: Objective. —To evaluate the efficacy and safety of anti—tumor necrosis factor α monoclonal antibody (TNF-α MAb) in the treatment of patients with sepsis syndrome. Design. —Randomized, prospective, multicenter, double-blind, placebo-controlled clinical trial. Setting. —A total of 31 hospitals in the United States and Canada. Patients. —There were 994 patients with sepsis syndrome enrolled in this clinical trial, and 971 patients were infused with the study drug. Intervention. —Patients were prospectively stratified into shock or nonshock groups and then randomized to receive a single infusion of 15 mg/kg of TNF-α MAb, 7.5 mg/kg of TNF-α MAb, or placebo. Patients received standard aggressive medical and surgical care during the 28-day postinfusion period. Outcome Measure. —Twenty-eight-day all-cause mortality. Results. —The distribution of variables describing demographics, organ system dysfunction or failure, preinfusion Acute Physiology and Chronic Health Evaluation II score, number of organs failing at baseline, initial sites of infection, infecting microorganisms, antimicrobials used, and initial invasive procedures was similar among patients in the TNF-α MAb and placebo treatment arms. Among all infused patients, there was no difference in all-cause mortality in patients who received placebo as compared with those who received TNF-α MAb. In septic patients with shock (n=478), there was a trend toward a reduction in all-cause mortality, which was most evident 3 days after infusion: 25 of 162 patients treated with 15 mg/kg of TNF-α MAb died, 22 of 156 patients treated with 7.5 mg/kg of TNF-α MAb died, and 44 of 160 patients in the placebo group died (15 mg/kg: 44% reduction vs placebo, P =.01; 7.5 mg/kg: 48.7% reduction vs placebo, P =.004). At day 28, the reduction in mortality for shock patients was not significant for either dose of TNF-α MAb relative to placebo (15 mg/kg, 61 deaths among 162 patients [37.7% mortality]; 7.5 mg/kg, 59 deaths among 156 patients [37.8% mortality]; placebo, 73 deaths among 160 patients [45.6% mortality]; P =.20 for 7.5 mg/kg and P =.15 for 15 mg/kg). Serious adverse events were reported in 4.6% of all infused patients. No immediate hypersensitivity allergic reactions due to TNF-α MAb were reported. Serum sickness—like reactions were seen in 2.5% of patients receiving TNF-α MAb. Conclusions. —There was no decrease in mortality between placebo and TNF-α MAb in all infused patients. In septic shock patients who received TNF-α MAb, a significant reduction in mortality was present 3 days after infusion. Although a trend toward reduced mortality continued at 28 days following treatment with TNF-α MAb, the difference in mortality among shock patients treated with placebo or TNF-α MAb was not significant. ( JAMA . 1995;273:934-941)

Coordinated Expression of Dopamine Receptors in Neostriatal Medium Spiny Neurons

Abstract: In recent years, the distribution of dopamine receptor subtypes among the principal neurons of the neostriatum has been the subject of debate. Conventional anatomical and physiological approaches have yielded starkly different estimates of the extent to which D1 and D2 class dopamine receptors are colocalized. One plausible explanation for the discrepancy is that some dopamine receptors are present in physiologically significant numbers, but the mRNA for these receptors is not detectable with conventional techniques. To test this hypothesis, we examined the expression of DA receptors in individual neostriatal neurons by patch-clamp and RT-PCR techniques. Because of the strong correlation between peptide expression and projection site, medium spiny neurons were divided into three groups on the basis of expression of mRNA for enkephalin (ENK) and substance P (SP). Neurons expressing detectable levels of SP but not ENK had abundant mRNA for the D1a receptor. A subset of these cells (approximately 50%) coexpressed D3 or D4 receptor mRNA. Neurons expressing detectable levels of ENK but not SP had abundant mRNA for D2 receptor isoforms (short and long). A subset (10-25%) of these neurons coexpressed D1a or D1b mRNAs. Neurons coexpressing ENK and SP mRNAs consistently coexpressed D1a and D2 mRNAs in relatively high abundance. Functional analysis of neurons expressing lower abundance mRNAs revealed clear physiological consequences that could be attributed to these receptors. These results suggest that, although colocalization of D1a and D2 receptors is limited, functional D1 and D2 class receptors are colocalized in nearly one-half of all medium spiny projection neurons.