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Overweight patients report weight discrimination in health care settings and subsequent avoidance of routine preventive health care. The purpose of this study was to examine implicit and explicit attitudes about weight among a large group of medical doctors (MDs) to determine the pervasiveness of negative attitudes about weight among MDs. Test-takers voluntarily accessed a public Web site, known as Project Implicit®, and opted to complete the Weight Implicit Association Test (IAT) (N = 359,261). A sub-sample identified their highest level of education as MD (N = 2,284). Among the MDs, 55% were female, 78% reported their race as white, and 62% had a normal range BMI. This large sample of test-takers showed strong implicit anti-fat bias (Cohen’s d = 1.0). MDs, on average, also showed strong implicit anti-fat bias (Cohen’s d = 0.93). All test-takers and the MD sub-sample reported a strong preference for thin people rather than fat people or a strong explicit anti-fat bias. We conclude that strong implicit and explicit anti-fat bias is as pervasive among MDs as it is among the general public. An important area for future research is to investigate the association between providers’ implicit and explicit attitudes about weight, patient reports of weight discrimination in health care, and quality of care delivered to overweight patients.  相似文献   
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Anti PSA monoclonal antibodies for diagnostic use were produced in an in vitro system. After purification using Protein G affinity chromatography a percentage of about 10% of antibody aggregates remained. The use of monoclonal antibodies containing aggregates as a capture antibody in a diagnostic kit reduces the performance of the test making it often unacceptable. The aggregates could be eliminated using gel filtration chromatography but, in that way, the final recovery of the whole production process was only about 50%. Aggregation is favoured when the working pH is near to the isoelectric point of the antibody. We varied the culture medium composition, modifying pH and osmolarity. We tested different values of pH and osmolarity: 7.1, 7.5, 8.0, 8.5 for pH, and 300, 340, 367, 395 mOsm/kg H2O for osmolarity. By modification of the cell culture medium we obtained a significant decrease of monoclonal antibody aggregates in the production cycle. In this way we achieved higher recovery rate and could avoid gel filtration polishing step. The experiments were performed in two stages: first in culture flasks changing one parameter in each experiment, and then in spinner bottle using the best conditions obtained in the first stage. During scale up we used the modifications achieved from the experiment showed in this paper in our production by hollow fibre bioreactor with positive results.  相似文献   
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Lubeluzole, a neuroprotective anti-ischemic drug, and its enantiomer were prepared following a convenient procedure based on hydrolytic kinetic resolution. The ee values were >99% and 96%, respectively, as assessed by HPLC analysis. The chemosensitizing effects of both enantiomers were evaluated in combination with either doxorubicin (human ovarian adenocarcinoma A2780 cells) or paclitaxel (human lung carcinoma A549 cells) by the MTT assay. At the lowest concentrations used, lubeluzole showed an overall and remarkable tendency to synergize with both anticancer drugs. In ovarian cancer cells a clear prevalence of antagonistic effect was observed for the R-enantiomer. The synergistic effects of lubeluzole for both drugs were observed over a wide concentration window (0.005–5 μM), the lowest limit being at least 40 times lower than human plasma concentrations previously reported as causing serious side effects.  相似文献   
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Dihydroorotases are universal proteins catalyzing the third step of pyrimidine biosynthesis. These zinc metalloenzymes belong to the superfamily of cyclic amidohydrolases, comprising also other enzymes that are involved in degradation of either purines (allantoinases), pyrimidines (dihydropyrimidinases) or hydantoins (hydantoinases). The evolutionary relationships between these mechanistically related enzymes were estimated after designing a method to build an accurate multiple sequence alignment. The amino acid sequences that have been crystallized were used to build a seed alignment. All the remaining homologues were progressively added by aligning their HMM profiles to the seed HMM profile, allowing to obtain a reliable phylogeny of the superfamily. This helped us to propose a new evolutionary classification of dihydroorotases into three major types, while at the same time disentangling an important part of the history of their complex structure–function relationships. Although differing in their substrate specificity, allantoinases, hydantoinases and dihydropyrimidinases are found to be phylogenetically closer to DHOase Type I than the proximity of the three DHOase types to each other. This suggests that the primordial cyclic amidohydrolase was a multifunctional, highly evolvable generalist, with high conformational diversity allowing for promiscuous activities. Then, successive gene duplications allowed resolving the primordial substrate ambiguity in various substrate specificities. The present-day superfamily of cyclic amidohydrolases is the result of the progressive divergence of these ancestral paralogous copies by descent with modification.  相似文献   
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Exendin-4 is a molecule currently used, in its synthetic form exenatide, for the treatment of type 2 diabetes mellitus. Exendin-4 binds and activates the Glucagon-Like Peptide-1 Receptor (GLP-1R), thus inducing insulin release. More recently, additional biological properties have been associated to molecules that belong to the GLP-1 family. For instance, Peptide YY and Vasoactive Intestinal Peptide have been found to affect cell adhesion and migration and our previous data have shown a considerable actin cytoskeleton rearrangement after exendin-4 treatment. However, no data are currently available on the effects of exendin-4 on tumor cell motility. The aim of this study was to investigate the effects of this molecule on cell adhesion, differentiation and migration in two neuroblastoma cell lines, SH-SY5Y and SK-N-AS. We first demonstrated, by Extra Cellular Matrix cell adhesion arrays, that exendin-4 increased cell adhesion, in particular on a vitronectin substrate. Subsequently, we found that this molecule induced a more differentiated phenotype, as assessed by i) the evaluation of neurite-like protrusions in 3D cell cultures, ii) the analysis of the expression of neuronal markers and iii) electrophysiological studies. Furthermore, we demonstrated that exendin-4 reduced cell migration and counteracted anchorage-independent growth in neuroblastoma cells. Overall, these data indicate for the first time that exendin-4 may have anti-tumoral properties.  相似文献   
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