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Physician perception of medication adherence may alter prescribing patterns. Perception of patients has been linked to readily observable factors, such as race and age. Obesity shares a similar stigma to these factors in society. We hypothesized that physicians would perceive patients with a higher BMI as nonadherent to medication. Data were collected from the baseline visit of a randomized clinical trial of patient–physician communication (240 patients and 40 physicians). Physician perception of patient medication adherence was measured on a Likert scale and dichotomized as fully adherent or not fully adherent. BMI was the predictor of interest. We performed Poisson regression analyses with robust variance estimates, adjusting for clustering of patients within physicians, to examine the association between BMI and physician perception of medication adherence. The mean (s.d.) BMI was 32.6 (7.7) kg/m2. Forty‐five percent of patients were perceived as nonadherent to medications by their physicians. Higher BMI was significantly and negatively associated with being perceived as adherent to medication (prevalence ratio (PrR) 0.76, 95% confidence interval (CI): 0.64–0.90; P = 0.002; per 10 kg/m2 increase in BMI). BMI remained significantly and negatively associated with physician perception of medication adherence after adjustment for patient and physician characteristics (PrR 0.80, 95% CI: 0.66–0.96; P = 0.020). In this study, patients with higher BMI were less likely to be perceived as adherent to medications by their providers. Physician perception of medication adherence has been shown to affect prescribing patterns in other studies. More work is needed to understand how this perception may affect the care of patients with obesity.  相似文献   
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Transmucosal transport rates for triolein in proximal and distal intestine were compared in unanesthetized rats. Emulsified [1-14-C] triolein together with bile and pancreatic juice from donor rats was infused for 6 hr into either the duodenum or the midpoint of the small intestine at such a rate that absorption was essentially complete in both regions of the intestine. Lymph was collected from the thoracic duct during triolein infusion and for an additional 6-hr period. The decrease in the rate of lymphatic output of labeled fat was found to follow a simple exponential function in all animals. This rate of decrease (decay rate) was used to calculate the half-times of lipid turnover through the intestinal wall and the fractional output rates. Distal intestine transported lipid 40% more slowly than proximal intestine, and the difference was associated with a greater accumulation of triglyceride in the distal intestinal wall. Chylomicron synthesis and/or release is the rate-limiting step for distal lymphatic fat transport in vivo, whereas fat uptake from the lumen is rate limiting for proximal intestine.  相似文献   
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Stbd1 is a protein of previously unknown function that is most prevalent in liver and muscle, the major sites for storage of the energy reserve glycogen. The protein is predicted to contain a hydrophobic N terminus and a C-terminal CBM20 glycan binding domain. Here, we show that Stbd1 binds to glycogen in vitro and that endogenous Stbd1 locates to perinuclear compartments in cultured mouse FL83B or Rat1 cells. When overexpressed in COSM9 cells, Stbd1 concentrated at enlarged perinuclear structures, co-localized with glycogen, the late endosomal/lysosomal marker LAMP1 and the autophagy protein GABARAPL1. Mutant Stbd1 lacking the N-terminal hydrophobic segment had a diffuse distribution throughout the cell. Point mutations in the CBM20 domain did not change the perinuclear localization of Stbd1, but glycogen was no longer concentrated in this compartment. Stable overexpression of glycogen synthase in Rat1WT4 cells resulted in accumulation of glycogen as massive perinuclear deposits, where a large fraction of the detectable Stbd1 co-localized. Starvation of Rat1WT4 cells for glucose resulted in dissipation of the massive glycogen stores into numerous and much smaller glycogen deposits that retained Stbd1. In vitro, in cells, and in animal models, Stbd1 consistently tracked with glycogen. We conclude that Stbd1 is involved in glycogen metabolism by binding to glycogen and anchoring it to membranes, thereby affecting its cellular localization and its intracellular trafficking to lysosomes.  相似文献   
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Evidence for multiple lytic pathways used by cytotoxic T lymphocytes   总被引:6,自引:0,他引:6  
Previous data generated by ourselves and others questioned the role of degranulation as a mechanism to explain CTL-mediated cytotoxicity. In this report we examine this tissue in greater depth. CTL-mediated lysis was probed with three different inhibitors. 4,4'-diisothiocyano-2,2'-disulfonic acid stilbene inhibits degranulation in a wide range of cell types, including CTL. EGTA, through chelation of Ca2+, also inhibits degranulation processes in CTL, and would inhibit other events or processes dependent on extracellular Ca2+. We also used prolonged exposure to PMA to exhaust PKC activity in CTL. Using these inhibitors, we have defined three pathways of lysis used by CTL. One pathway requires Ca2+, is PMA sensitive, but does not depend on degranulation. The second pathway is independent of Ca2+, is not PMA sensitive, and also does not depend on degranulation. All primary CTL and cloned CTL lyse most target cells via pathway I. However, when confronted with certain target cells (which we have referred to previously as Ca2+-independent target cells), pathway II is induced. When pathway II is induced, pathway I apparently shuts down. We show here that pathway II does not depend on protein synthesis, and that it also leads to DNA solubilization in target cells. A limited number of cloned CTL use pathways I and II as just described, but use in addition, and simultaneously, a third pathway that appears to involve degranulation. This pathway is seen irregularly in most CTL clones, and may be influenced by levels of IL-2 in the culture medium.  相似文献   
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Rat renal phosphate-dependent glutaminase is rapidly inactivated by incubating with L-2-amino-4-oxo-5-chloropentanoic scid. Concentrations of phosphate, which increase the glutaminase activity, decrease the rate of inactivation by chloroketone. In addition, inactivation is not blocked by glutamine. Instead, glutamate was shown to specifically reduce the rate of chloroketone inactivation. Upon sodium lauryl sulfate-polyacrylamide gel electrophoresis, the purified glutaminase preparation exhibits at least five protein staining bands which range in molecular weight from 57,000 to 75,000. Studies with 14C-labeled chloroketone indicate that this reagent reacts with each of these peptides. The mean stoichiometry of binding was calculated to be 1.3 mol/mol of enzyme. Therefore, these results indicate that the glutaminase may contain a specific site for binding glutamate and that the purified enzyme consists of a series of related peptides which may have resulted from partial proteolysis.  相似文献   
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