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An industrial grade acidic crude palm oil (ACPO) pre-treatment process was carried out using ethanesulfonic acid (ESA) as a catalyst in the esterification reaction. ESA was used in different dosages to reduce free fatty acid (FFA) to a minimum level for the second stage of biodiesel production via alkaline transesterification reaction. Different process operating conditions were optimized such as ESA dosage (0.25-3.5% wt/wt), methanol to ACPO molar ratio (1:1-20:1), reaction temperature (40-70 °C), and reaction time (3-150 min). This study revealed the potential use of abundant quantities of ACPO from oil palm mills for biodiesel production. The lab scale results showed the effectiveness of the pre-treatment process using ESA catalyst. Three consecutive catalyst recycling runs were achieved without significant degradation in its performance. Second and third reuse runs needed more reaction time to achieve the target level of FFA content. Esterification and transesterification using ESA and KOH respectively is proposed for biodiesel industrial scale production. The produced biodiesel meets the international standards specifications for biodiesel fuel (EN 14214 and ASTM D6751).  相似文献   
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Non-alcoholic fatty liver disease (NAFLD) is a condition defined by significant lipid accumulation (5–10%) in hepatic tissue in the absence of significant chronic alcohol consumption. We aim to detect frequency of fatty liver among overweight/obese adults and children and associated clinical; anthropological measures; biochemical; genetic and imaging studies. Eighty three consecutive adults and 72 children included in the study. All patients underwent clinical measurements of height, body weight, body mass index (BMI), waist and hip circumference. Biochemical investigations were done to all subjects including liver function tests; lipid profile; fasting blood glucose; insulin resistance (IR); high sensitivity C reactive protein (hs-CRP); adiponectin and genotyping of adiponectin genes. Abdominal ultrasonography was done to search for fatty liver; to measure subcutaneous fat thickness (SFT) and visceral fat thickness (VFT). Fatty liver was detected in 47 (65.3%) children and in 52 (62.7%) adults. Correlation analysis in both groups revealed that enlarged liver was highly positively correlated to age; BMI, systolic blood pressure (SBP), diastolic blood pressure (DBP); waist circumference; hip circumference, subcutaneous fat thickness (SFT) and Visceral fat thickness (VFT), alanine aminotransferase (ALT), aspartate aminotransferase/alanine aminotransferase (AST/ALT). In addition in adults to fasting blood glucose, cholesterol, triglycerides (TG), low density lipoprotein (LDL), IR and hs-CRP. Homozygous T adiponectin genotype at position +276 was significantly increased among children with enlarged liver size and hs-CRP. NAFLD affects a substantial portion of adults and children; it is associated with the metabolic syndrome.  相似文献   
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There is insufficient research on the direct effects of food advertising on children's diet and diet-related health, particularly in non-experimental settings. We employ a nationally-representative sample from the Early Childhood Longitudinal Survey–Kindergarten Cohort (ECLS-K) and the Nielsen Company data on spot television advertising of cereals, fast food restaurants and soft drinks to children across the top 55 designated-market areas to estimate the relation between exposure to food advertising on television and children's food consumption and body weight. Our results suggest that soft drink and fast food television advertising is associated with increased consumption of soft drinks and fast food among elementary school children (Grade 5). Exposure to 100 incremental TV ads for sugar-sweetened carbonated soft drinks during 2002–2004 was associated with a 9.4% rise in children's consumption of soft drinks in 2004. The same increase in exposure to fast food advertising was associated with a 1.1% rise in children's consumption of fast food. There was no detectable link between advertising exposure and average body weight, but fast food advertising was significantly associated with body mass index for overweight and obese children (≥85th BMI percentile), revealing detectable effects for a vulnerable group of children. Exposure to advertising for calorie-dense nutrient-poor foods may increase overall consumption of unhealthy food categories.  相似文献   
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BACKGROUND AND PURPOSE: The purpose of this study was to derive quantitative parameters from magnetic resonance (MR) spectroscopic, perfusion, and diffusion imaging of grade 2 gliomas according to the World Health Organization and to investigate how these multiple imaging modalities can contribute to evaluating their histologic subtypes and spatial characteristics. MATERIALS AND METHODS: MR spectroscopic, perfusion, and diffusion images from 56 patients with newly diagnosed grade 2 glioma (24 oligodendrogliomas, 18 astrocytomas, and 14 oligoastrocytomas) were retrospectively studied. Metabolite intensities, relative cerebral blood volume (rCBV), and apparent diffusion coefficient (ADC) were statistically evaluated. RESULTS: The 75th percentile rCBV and median ADC were significantly different between oligodendrogliomas and astrocytomas (P < .0001) and between oligodendrogliomas and oligoastrocytomas (P < .001). Logistic regression analysis identified both 75th percentile rCBV and median ADC as significant variables in the differentiation of oligodendrogliomas from astrocytomas and oligoastrocytomas. Group differences in metabolite intensities were not significant, but there was a much larger variation in the volumes and maximum values of metabolic abnormalities for patients with oligodendroglioma compared with the other tumor subtypes. CONCLUSIONS: Perfusion and diffusion imaging provide quantitative MR parameters that can help to differentiate grade 2 oligodendrogliomas from grade 2 astrocytomas and oligoastrocytomas. The large variations in the magnitude and spatial extent of the metabolic lesions between patients and the fact that their values are not correlated with the other imaging parameters indicate that MR spectroscopic imaging may provide complementary information that is helpful in targeting therapy, evaluating residual disease, and assessing response to therapy.  相似文献   
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Allergens are initiators of both innate and adaptive immune responses. They are recognised at the site of entry by epithelial and dendritic cells (DCs), both of which activate innate inflammatory circuits that can collectively induce Th2 immune responses. In an attempt to have a better understanding of the role of carbohydrates in the recognition and uptake of allergens by the innate immune system, we defined common glycosylation patterns in major allergens. This was done using labelled lectins and showed that allergens like Der p 1 (Dermatophagoides pteronyssinus group 1), Fel d 1 (Felis domisticus), Ara h 1 (Arachis hypogaea), Der p 2 (Dermatophagoides pteronyssinus group 2), Bla g 2 (Blattella germanica) and Can f 1 (Canis familiaris) are glycosylated and that the main dominant sugars on these allergens are 1-2, 1-3 and 1-6 mannose. These observations are in line with recent reports implicating the mannose receptor (MR) in allergen recognition and uptake by DCs and suggesting a major link between glycosylation and allergen recognition. We then looked at TSLP (Thymic Stromal Lymphopoietin) cytokine secretion by lung epithelia upon encountering natural Der p 1 allergen. TSLP is suggested to drive DC maturation in support of allergic hypersensitivity reactions. Our data showed an increase in TSLP secretion by lung epithelia upon stimulation with natural Der p 1 which was carbohydrate dependent. The deglycosylated preparation of Der p 1 exhibited minimal uptake by DCs compared to the natural and hyperglycosylated recombinant counterparts, with the latter being taken up more readily than the other preparations. Collectively, our data indicate that carbohydrate moieties on allergens play a vital role in their recognition by innate immune cells, implicating them in downstream deleterious Th2 cell activation and IgE production.  相似文献   
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The present study was undertaken to explore the effect of the administration of high doses of sodium selenite on apoptosis in polymorphonuclear leukocytes in patients with non-Hodgkin's lymphoma. Thirty patients with newly diagnosed non-Hodgkin's lymphoma were randomly divided into two groups. Group I was treated with chemotherapy and group II received 0.2 mg/kg/d sodium selenite in addition to chemotherapy. Flow cytometry was used for the monitoring of apoptosis on peripheral blood neutrophils at the time of diagnosis and after treatment in both groups of patients. Sodium selenite administration resulted in a significant reduction in neutrophils apoptosis (82+/-10% vs 32+/-18%, p<0.05) and this was associated with significant reduction in infection rate following chemotherapy (67% vs 20%, p<0.05). Also, significant improvement in cardiac ejection fraction was observed (62+/-4% vs 69+/-5% p<0.05). It is concluded that sodium selenite administration at the dosage chosen acts as a cytoprotective agent, alleviating side effects and immunosuppressive effects of cytotoxic chemotherapeutic agents.  相似文献   
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Research has mostly focused on obesity and not on processes of BMI change more generally, although these may be key factors that lead to obesity. Studies have suggested that obesity is affected by social ties. However these studies used survey based data collection techniques that may be biased toward select only close friends and relatives. In this study, mobile phone sensing techniques were used to routinely capture social interaction data in an undergraduate dorm. By automating the capture of social interaction data, the limitations of self-reported social exposure data are avoided. This study attempts to understand and develop a model that best describes the change in BMI using social interaction data.We evaluated a cohort of 42 college students in a co-located university dorm, automatically captured via mobile phones and survey based health-related information. We determined the most predictive variables for change in BMI using the least absolute shrinkage and selection operator (LASSO) method. The selected variables, with gender, healthy diet category, and ability to manage stress, were used to build multiple linear regression models that estimate the effect of exposure and individual factors on change in BMI. We identified the best model using Akaike Information Criterion (AIC) and R2.This study found a model that explains 68% (p<0.0001) of the variation in change in BMI. The model combined social interaction data, especially from acquaintances, and personal health-related information to explain change in BMI.This is the first study taking into account both interactions with different levels of social interaction and personal health-related information. Social interactions with acquaintances accounted for more than half the variation in change in BMI. This suggests the importance of not only individual health information but also the significance of social interactions with people we are exposed to, even people we may not consider as close friends.  相似文献   
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Invariant NKT (iNKT) cells are glycolipid-reactive lymphocytes with anti-microbial properties. Toll-like receptor (TLR)-primed antigen-presenting cells are known to activate iNKT cells, however, the expression and function of TLRs in iNKT cells remain largely unknown. Here, we show that TCR-activation of murine iNKT cells by α-GalactosylCeramide (α-GalCer) or anti-CD3 antibodies can result in increased expression of TLR genes. TLR3, 5 and 9-mediated costimulation of TCR-preactivated iNKT cells resulted in enhancement of iNKT cell activation, as determined by their cytokine production. Expression of TLR3 and 9 at protein level was also confirmed in TCR-activated iNKT cells. Furthermore, TCR-preactivation followed by TLR9-costimulation of iNKT cells increased their ability to induce maturation of dendritic cells. Thus, our findings show that iNKT cells can up-regulate their TLR expression upon TCR activation and a subsequent TLR-signaling in these cells can lead to their enhanced activation, suggesting a new possible mode of iNKT cell activation.  相似文献   
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