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161.
Cristiana Araújo Gontijo Bruna Borges Macedo Cabral Laura Cristina Tibiletti Balieiro Gabriela Pereira Teixeira Walid Makin Fahmy Yara Cristina de Paiva Maia 《Chronobiology international》2019,36(1):75-84
Animal studies strongly suggest that timed feeding can have beneficial physiological effects, including protection against the obesogenic and metabolic consequences of a high-fat diet. However, the relationship between variables related to the timing of eating and diet quality in pregnancy women, which is considered as a period of nutritional vulnerability, is still poorly described in the literature. Therefore, the aim of the present study was to investigate the associations between time-related eating patterns and chronotype with diet quality of pregnant women. This cross-sectional study was conducted with 100 pregnant women in the first gestational trimester (≤12 weeks of gestation). The information regarding food intake was obtained by three 24-Hour Dietary Recall (24HR). Time-related eating patterns, i.e., the interval between the first and the last meal (eating duration), nightly fasting, time of the first and last meals, and number of meals eating on a day were determined. Chronotype was derived using the mid-sleep time on free days on weekends, with a further correction for calculated sleep debt. Diet quality was evaluated using the Brazilian Healthy Eating Index-Revised (BHEI-R), validated for the Brazilian population. Linear regression modeling analyses adjusted for confounders were used to investigate the association between time-related eating patterns and chronotype with diet quality. The BHEI-R total score was negatively associated with time of the first meal (β = ?0.355; p = 0.002; r2 adjusted = 0.141), and positively associated with eating duration (β = 0.262; p = 0.024; r2 adjusted = 0.086) and number of meals (β = 0.273; p = 0.019; r2 adjusted = 0.091). In addition, the score of total fruit component was negatively associated with chronotype (β = ?0.236; p = 0.033; r2 adjusted = 0.078), time of the first meal (β = ?0.393; p = 0.001; r2 adjusted = 0.171), and positively associated with eating duration (β = 0.259; p = 0.022; r2 adjusted = 0.087) and number of meals (β = 0.376; p = 0.001; r2 adjusted = 0.159). The score for whole fruit component was negatively associated with time of the first meal (β = ?0.388; p = 0.001; r2 adjusted = 0.152), and positively associated with number of meals (β = 0.403; p = 0.001; r2 adjusted = 0.164). A longer eating duration, earlier time of the first meal, higher number of meals and morningness tendency are associated with a better diet quality in the first gestational trimester – higher scores of the total BHEI-R and/or fruit components. We suggest that nutritional guidelines should consider time-related eating patterns and chronotype to ensure good diet quality of pregnant women since the beginning of gestation, contributing on prevention of metabolic-nutritional complications. 相似文献
162.
Regulation of immune response is marked by complex interactions among the cells that recognize and present antigens. Antigen presenting cells (APCs), the antigen presenting cell component of the innate immune response plays an important role in effector CD4+ T cell response. Thermal injury and/or superimposed sepsis in rats' leads to suppressed CD4+ T cell functions. We investigated modulations of CD4+ T cell function by APCs (purified non-T cells) from thermally injured and/or septic rats. Rats were subjected to 30% total body surface area scald burn or exposed to 37 degrees C water (Sham burn) and sepsis was induced by cecal-ligation and puncture (CLP) method. At day 3 post-injury animals were sacrificed and CD4+ T cells and APCs from mesenteric lymph nodes (MLN) were obtained using magnetic microbead isolation procedure. APCs from injured rats were co-cultured with sham rat MLN CD4+ T cells and proliferative responses (thymidine incorporation), phenotypic changes (Flow cytometry), IL-2 production (ELISA) and CTLA-4 mRNA (RT-PCR) were determined in naive rat CD4+ T cells. The data indicate that APCs from thermally injured and/or septic rats when co-cultured with CD4+ T cells suppressed CD4+ T cell effector functions. This lack of CD4+ T cell activation was accompanied with altered co-stimulatory molecules, i.e., CD28 and/or CTLA-4 (CD152). In conclusion, our studies indicated that defective APCs from thermally injured and/or septic rats modulate CD4+ T cell functions via changes in co-stimulatory molecules expressed on naive CD4+ T cells. This altered APC: CD4+ T cell interaction leads to suppressed CD4+ T cell activation of healthy animals. 相似文献
163.
164.
Both Acetate Kinase and Acetyl Coenzyme A Synthetase Are Involved in Acetate-Stimulated Change in the Direction of Flagellar Rotation in Escherichia coli 总被引:2,自引:0,他引:2 下载免费PDF全文
Escherichia coli strains overproducing the response regulator CheY respond to acetate by increasing their clockwise bias of flagellar rotation, even when they lack other chemotaxis proteins. With acetate metabolism mutants, we demonstrate that both acetate kinase and acetyl coenzyme A synthetase are involved in this response. Thus, a response was observed when one of these enzymes was missing but not when both were absent. 相似文献
165.
166.
The yeast-like epiphytic fungus Pseudozyma flocculosa is known to antagonize powdery mildew fungi through proliferation on colonies presumably preceded by the release of an antifungal
glycolipid (flocculosin). In culture conditions, P. flocculosa can be induced to produce or not flocculosin through manipulation of the culture medium nutrients. In order to characterize
and understand the metabolic changes in P. flocculosa linked to glycolipid production, we conducted a 2-DE proteomic analysis and compared the proteomic profile of P. flocculosa growing under conditions favoring the development of the fungus (control) or conducive to flocculosin synthesis (stress).
A large number of protein spots (771) were detected in protein extracts of the control treatment compared to only 435 matched
protein spots in extracts of the stress cultures, which clearly suggests an important metabolic reorganization in slow-growing
cells producing flocculosin. From the latter treatment, we were able to identify 21 protein spots that were either specific
to the treatment or up-regulated significantly (2-fold increase). All of them were identified based on similarity between
predicted ORF of the newly sequenced genome of P. flocculosa with Ustilago maydis' available annotated sequences. These proteins were associated with the carbon and fatty acid metabolism, and also with the
filamentous change of the fungus leading to flocculosin production. This first look into the proteome of P. flocculosa suggests that flocculosin synthesis is elicited in response to specific stress or limiting conditions. 相似文献
167.
Chang YW Putzer K Ren L Kaboord B Chance TW Qoronfleh MW Jakobi R 《Journal of cellular biochemistry》2005,96(2):314-329
Cyclooxygenase 2 (COX-2) is an immediate early gene induced by a variety of stimuli and its expression is stimulated by individual activation of Ras or Rho GTPases. Here we investigate the role of coordinate activation of Ras and Rho GTPases in the induction of COX-2. Individual expression of constitutively active Ras, RhoA, or Rac1 was capable of stimulating COX-2 expression in NIH3T3 cells, but co-expression of constitutively active RhoA with either constitutively active Ras or Rac1 was required for full stimulation of COX-2 expression. Serum growth factors differentially activated Ras, RhoA, and Rac1, which correlated with the activation of Raf-1, ERK, and c-Jun as well as with induction of COX-2. Inhibition of Ras significantly blocked the activation of Raf-1, ERK, and c-Jun and the stimulation of COX-2 expression in response to serum. In contrast, inhibition of Rho family GTPases partially blocked serum induction of ERK activation but had little effects on COX-2 expression. Both inhibitors of MEK (PD098059) and JNK (SP600125) inhibited serum induction of COX-2. PD98059 only inhibited constitutively active Ras-induced COX-2 expression, while SP600125 significantly inhibited both constitutively active Ras- and RhoA-induced COX-2 expression. Together, our data suggest that constitutively active oncogenic Ras and Rho coordinately stimulate COX-2 expression whereas transient activation of Ras but not RhoA or Rac1 mediates the induction of COX-2 in response to serum. Furthermore, ERK and JNK activation are both required for serum- and oncogenic Ras-mediated COX-2 expression whereas only JNK activation is required for oncogenic RhoA-mediated stimulation of COX-2 expression. 相似文献
168.
Dianyu Yu Xu Zhang Dezhi Zou Tong Wang Tianyi Liu Liqi Wang Walid Elfalleh Lianzhou Jiang 《Food biophysics》2018,13(2):208-215
Candida antarctica lipase B (CALB) was immobilized on Fe3O4/SiOx-g-P(GMA) polymer carrier to catalyzed the transesterification of soybean oil and phytosterol. The enzyme loading of the obtained particles was 98.7 mg/g supports and the enzyme activity was 1226.5 U/g. The average particle size was 100.5?±?1.30 nm and the magnetization was 15.80 emu/g. The immobilized enzyme showed higher activities at a wider range of pH and temperatures. Its optimum reaction temperature was up to 50 °C; increased by 5 °C compared to the free enzyme. The obtained magnetic immobilized Fe3O4/SiOx-g-P(GMA) lipase was nanoscale. First-grade soybean oils were used as a substrate. System pH was adjusted to 7.0. The optimal reaction temperature was 50 °C and the reaction time was 3 h. The phytosterol concentration of 5% and immobilized CALB of 2% were obtained. The conversion rate of transesterification reaction between soybean oil and phytosterol was 86.2%. The use of magnets can quickly separate the immobilized enzymes from the substrates. The relative activity of the immobilized enzymes was 83.0% when reused seven times. The prepared immobilized CALB can improve efficiently enzyme activity and reutilization. 相似文献
169.
Toxicity of fipronil to German and American cockroaches 总被引:2,自引:0,他引:2
Walid Kaakeh Byron L. Reid Gary W. Bennett 《Entomologia Experimentalis et Applicata》1997,84(3):229-237
Topical and oral toxicity of fipronil, compared to chlorpyrifos, was determined for the German cockroach, Blattella germanica (L.), and American cockroach, Periplaneta americana (L.). Fipronil and Combat bait matrices were evaluated for their attractancies to both species. In the topical toxicity tests, LD50's of fipronil, at 72 h after topical application, were 0.03 and 0.02 µg/g for adult B. germanica and P. americana, respectively. Fipronil was significantly more toxic than topically applied chlorpyrifos (LD50's were 0.06 and 0.16 µg/g for B. germanica and P. americana, respectively). The oral toxicity of fipronil and chlorpyrifos in Petri dish experiments, against both species, was affected by stage (for B. germanica), diet concentration, and feeding assay. Fipronil caused higher mortality of B. germanica than chlorpyrifos in two feeding assays (continuous and abbreviated). Both compounds were equally toxic to adult males of P. americana at all rates. Fipronil caused higher nymphal mortality than chlorpyrifos 48–72 h after exposure in both feeding assays. In large population chamber tests, fipronil bait was more effective and faster in killing P. americana than Raid and Combat. LT50's were 0.8, 2.4, and 7.6 d for fipronil, Raid (a.i. = chlorpyrifos), and Combat (a.i. = hydramethylnon) baits, respectively. Mortality reached 96.5, 93.4, and 84.6%, respectively, at the end of the 14 d test. In the bait attractancy tests, both strains of B. germanica were attracted similarly to fipronil and Combat bait matrices. P. americana were attracted more to fipronil than to Combat bait matrix or to other alternative foods. 相似文献
170.