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111.
Animal studies indicate that monosodium glutamate (MSG) can induce hypothalamic lesions and leptin resistance, possibly influencing energy balance, leading to overweight. This study examines the association between MSG intake and overweight in humans. We conducted a cross-sectional study involving 752 healthy Chinese (48.7% women), aged 40-59 years, randomly sampled from three rural villages in north and south China. The great majority of participants prepared their foods at home, without use of commercially processed foods. Diet was assessed with four in-depth multipass 24-h recalls. Participants were asked to demonstrate MSG amounts added in food preparation. Amounts shaken out were weighed by trained interviewers. Overweight was defined as BMI > or =25.0 or > or =23.0 kg/m(2)(based on World Health Organization recommendations for Asian populations). Eighty-two percent of participants were MSG users. Average intake was 0.33 g/day (s.d. = 0.40). With adjustment for potential confounders including physical activity and total energy intake, MSG intake was positively related to BMI. Prevalence of overweight was significantly higher in MSG users than nonusers. For users in the highest tertile of MSG intake compared to nonusers, the multivariable-adjusted odds ratios of overweight (BMI > or =23.0 and > or =25.0) were 2.10 (95% confidence interval, 1.13-3.90, P for trend across four MSG categories = 0.03) and 2.75 (95% confidence interval, 1.28-5.95, P = 0.04). This research provides data that MSG intake may be associated with increased risk of overweight independent of physical activity and total energy intake in humans.  相似文献   
112.
We reported an integrated platform to explore serum protein variant pattern in cancer and its utility as a new class of biomarker panel for diagnosis. On the model study of serum amyloid A (SAA), we employed nanoprobe‐based affinity mass spectrometry for enrichment, identification and quantitation of SAA variants from serum of 105 gastric cancer patients in comparison with 54 gastritis patients, 54 controls, and 120 patients from other cancer. The result revealed surprisingly heterogeneous and most comprehensive SAA bar code to date, which comprises 24 SAA variants including SAA1‐ and SAA2‐encoded products, polymorphic isoforms, N‐terminal–truncated forms, and three novel SAA oxidized isotypes, in which the variant‐specific peptide sequence were also confirmed by LC‐MS/MS. A diagnostic model was developed for dimension reduction and computational classification of the 24 SAA‐variant bar code, providing good discrimination (AUC = 0.85 ± 3.2E?3) for differentiating gastric cancer group from gastritis and normal groups (sensitivity, 0.76; specificity, 0.81) and was validated with external validation cohort (sensitivity, 0.71; specificity, 0.74). Our platform not only shed light on the occurrence and modification extent of under‐represented serum protein variants in cancer, but also suggested a new concept of diagnostic platform by serum protein variant profile.  相似文献   
113.
Susceptibility to tuberculosis (TB) may be affected by host genetic factors. Elevated levels of transforming growth factor-beta 1 (TGF-β1) were found in plasma of patients with active TB compared with those of healthy contacts. To investigate the association of TGF-β1 gene polymorphisms (C-509T and T869C) and plasma levels with the risk of TB in Hong Kong Chinese adults, a case-control study was carried out on 174 active TB patients and 174 healthy controls matched for age, gender and smoking. Blood samples from 180 blood donors served as another control group. Genotyping was carried out on genomic DNA using polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). Plasma TGF-β1 was measured by commercially available ELISA kit. We found no differences in the distribution of genotypes or alleles of TGF-β1 gene polymorphisms at C-509T and T869C between patients and either group of healthy controls. Patients with TB had elevated plasma TGF-β1 levels compared with healthy controls irrespective of their genotypes (p < 0.001). In conclusion, TGF-β1 gene polymorphism at C-509T and T869C is not associated with TB susceptibility in Hong Kong Chinese adults, but elevated plasma TGF-β1 levels suggests that this cytokine may play a role in the pathogenesis of tuberculosis.  相似文献   
114.
The course of acute infection of mice with ts mutant or the native strain DNA and the antigens of HSV in brain nerve cells were determined. Virus DNA was detected in brains of all mice in both animal groups while the virus antigens--only in cells of mice infected with the native strain. It can be suggested, therefore, that the ability of ts mutant to replicate in central nervous system of the infected mice is lacking or much lower. The detection of virus nucleic acid 3-5 months after virus infection might indicate a possibility of establishing latent infection. However, ts mutant showed a significantly lower possibility of latency induction, as compared with highly virulent strains. It was found that the mutant ability to induce latent infection was markedly increased when mice were treated with both ts mutant and Depo-Medrol as immunosuppressive agent. This finding shows both a possibility of increase of frequency of latent infections in the state of immunosuppression, and of activation of the latent infection (recurrence of acute form of infection).  相似文献   
115.
MOTIVATION: Inner holes, artifacts and blank spots are common in microarray images, but current image analysis methods do not pay them enough attention. We propose a new robust model-based method for processing microarray images so as to estimate foreground and background intensities. The method starts with a very simple but effective automatic gridding method, and then proceeds in two steps. The first step applies model-based clustering to the distribution of pixel intensities, using the Bayesian Information Criterion (BIC) to choose the number of groups up to a maximum of three. The second step is spatial, finding the large spatially connected components in each cluster of pixels. The method thus combines the strengths of the histogram-based and spatial approaches. It deals effectively with inner holes in spots and with artifacts. It also provides a formal inferential basis for deciding when the spot is blank, namely when the BIC favors one group over two or three. RESULTS: We apply our methods for gridding and segmentation to cDNA microarray images from an HIV infection experiment. In these experiments, our method had better stability across replicates than a fixed-circle segmentation method or the seeded region growing method in the SPOT software, without introducing noticeable bias when estimating the intensities of differentially expressed genes. AVAILABILITY: spotSegmentation, an R language package implementing both the gridding and segmentation methods is available through the Bioconductor project (http://www.bioconductor.org). The segmentation method requires the contributed R package MCLUST for model-based clustering (http://cran.us.r-project.org). CONTACT: fraley@stat.washington.edu.  相似文献   
116.
Id-1 is a member of the HLH protein family that regulates a wide range of cellular processes such as cell proliferation, apoptosis, senescence and overexpression of Id-1 was recently suggested to play roles in the development and progression of different cancers. Previously, Id-1 was shown to physically interact with the viral protein E1A. Meanwhile, Id-1 expression was found to be regulated by several of the virus-encoded proteins, suggesting that Id-1 may be a common cellular target of the viral proteins. Here, we report that Id-1 interacts with the Hepatitis-B virus (HBV)-encoded protein HBX and regulates its stability in hepatocellular carcinoma (HCC) cells. We found that in HCC cells, ectopic Id-1 expression significantly decreased the half-life of the HBX protein, indicating that HBX is destabilized by Id-1. Meanwhile, the Id-1-induced HBX degradation was found to be inhibited by treatment with proteasome inhibitor, suggesting that this process is mediated through the proteasome pathway. Interestingly, while Id-1 did not induce HBX-ubiquitination, we found that removal of all the lysine residues of the HBX protein protects it from the effect of Id-1, indicating that ubiquitination is still required for the Id-1-mediated HBX degradation. Meanwhile, we found that Id-1 binds to the proteasome subunit C8 and facilitates its interaction with the HBX protein and disruption of this interaction completely abolishes the negative effect of Id-1 on HBX protein stability. Taken together, our results demonstrated a novel function of Id-1 in regulating HBX protein stability through interaction with the proteasome.  相似文献   
117.
Alteration of the gut microbiota plays an important role in animal health and metabolic diseases. However, little is known with respect to the influence of environmental osmolality on the gut microbial community. The aim of the current study was to determine whether the reduction in salinity affects the gut microbiota and identify its potential role in salinity acclimation. Using Oryzias melastigma as a model organism to perform progressive hypotonic transfer experiments, we evaluated three conditions: seawater control (SW), SW to 50% sea water transfer (SFW) and SW to SFW to freshwater transfer (FW). Our results showed that the SFW and FW transfer groups contained higher operational taxonomic unit microbiota diversities. The dominant bacteria in all conditions constituted the phylum Proteobacteria, with the majority in the SW and SFW transfer gut comprising Vibrio at the genus level, whereas this population was replaced by Pseudomonas in the FW transfer gut. Furthermore, our data revealed that the FW transfer gut microbiota exhibited a reduced renin–angiotensin system, which is important in SW acclimation. In addition, induced detoxification and immune mechanisms were found in the FW transfer gut microbiota. The shift of the bacteria community in different osmolality environments indicated possible roles of bacteria in facilitating host acclimation.  相似文献   
118.
119.
Evolving evidence supports that cyclooxygenase-1 (COX-1) takes part in colon carcinogenesis. The effects of COX-1 inhibition on colon cancer cells, however, remains obscured. In this study, we demonstrate that COX-1 inhibitor sc-560 inhibited colon cancer cell proliferation with concomitant G0/G1-phase cell cycle arrest. The anti-proliferative effect was associated with down-regulation of c-Fos, cyclin E2 and E2F-1 and up-regulation of p21Waf1/Cip1 and p27Kip1. In addition, sc-560 induced macroautophagy, an emerging mechanism of tumor suppression, as evidenced by the formation of LC3+ autophagic vacuoles, enhanced LC3 processing, and the accumulation of acidic vesicular organelles and autolysosomes. In this connection, 3-methyladenine, a Class III phosphoinositide 3-kinase inhibitor, significantly abolished the formation of LC3+ autophagic vacuoles and the processing of LC3 induced by sc-560. To conclude, this study reveals the unreported relationship between COX-1 and proliferation/macroautophagy of colon cancer cells.  相似文献   
120.
Studies were performed in the years 1986-1990 and dealing with 405 clinical materials originating from infections within the abdominal cavity, maxilla, reproductive organ, post-operative wounds as well as dressings, extremities, blood, bile and other types of material and usefulness of analysis by gas chromatography of presence of lower fatty acids in materials for rapid and preliminary diagnostics with strictly anaerobic bacteria was confirmed. Presence in chromatograms of isobutyric, butyric isovaleric, valeric, isocaproic and caproic acid, and partly of propionic acid, is a good indication of infection with strictly anaerobic bacteria. Moreover, presence of succinic acid may suggest presence of anaerobic infection, similarly as presence in chromatograms of three or more various lower fatty acids. Rapid, approximative diagnosis of anaerobic bacteria by application of gas chromatography is worth of broader application. Investigation of clinical material by this method lasts only 1-2 hours and obtained results my present a basis for preliminary diagnosis of the etiological factor and for direction of chemotherapy, which is very important in most early period of treatment of infections.  相似文献   
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