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排序方式: 共有10000条查询结果,搜索用时 12 毫秒
71.
Anjali Ramaswamy Nina N. Brodsky Tomokazu S. Sumida Michela Comi Hiromitsu Asashima Kenneth B. Hoehn Ningshan Li Yunqing Liu Aagam Shah Neal G. Ravindra Jason Bishai Alamzeb Khan William Lau Brian Sellers Neha Bansal Pamela Guerrerio Avraham Unterman Victoria Habet Carrie L. Lucas 《Immunity》2021,54(5):1083-1095.e7
72.
Effects of a brisk walk on lipoprotein lipase activity and plasma triglyceride concentrations in the fasted and postprandial states 总被引:3,自引:0,他引:3
This study aimed to determine whether changes in plasma heparin-releasable lipoprotein lipase (LPL) activity following a brisk
walk were associated with decreases in fasting and/or postprandial triglyceride (TG) concentrations. Two groups of pre-menopausal
women participated. In one group (fasting study group, n=10), TG concentrations and post-heparin plasma LPL activity were measured in the fasted state on two occasions: ~18 h after
a 2-h treadmill walk at 50% maximal oxygen uptake (exercise trial); and after a day of no exercise (control trial). The other
group (postprandial study group, n=9) undertook two oral fat tolerance tests (blood samples taken fasting and for 6 h after a high-fat meal), with plasma LPL
activity measured 6 h after meal ingestion. Pre-conditions were the same as for the fasting study group (i.e. control and
prior exercise). Prior exercise reduced fasting TG concentrations by 23 (7)% (fasting study group) [mean (SEM)] and by 18
(9)% (postprandial study group) (both P<0.05), and the postprandial TG response by 23 (6)% (postprandial study group) (P<0.01). Plasma LPL activity was not significantly increased by exercise in either the fasting or postprandial study groups.
However, exercise-induced changes in both fasting and postprandial LPL activity were significantly correlated with the respective
exercise-induced changes in fasting TG concentration and the postprandial TG response (r=−0.70 and −0.77 respectively, P<0.05 for both). These data suggest that increased LPL activity may contribute to the hypotriglyceridaemic effect of moderate
exercise, although other mechanisms are also likely to be involved.
Electronic Publication 相似文献
73.
Effects of Colloidal Resuscitation Fluids on Reticuloendothelial Function and Resistance to Infection after Hemorrhage 总被引:3,自引:0,他引:3 下载免费PDF全文
Ed A. M. van Rijen Jason J. Ward Roderick A. Little 《Clinical and Vaccine Immunology : CVI》1998,5(4):543-549
The effects of three resuscitation fluids, hydroxyethyl starch (HES), Haemaccel, and fresh autologous blood, on reticuloendothelial system phagocytic and catabolic functions and resistance to infection after 40% hemorrhages in BALB/c mice were studied. The mice, anesthetized with isoflurane, were bled over a 10-min period, left hypovolemic for 30 min, and then resuscitated with their shed blood or the same volume of asanguineous fluid. Normothermia was maintained throughout the experiments. The uptake and catabolism of intravenously injected double-labelled sheep erythrocytes (51Cr-125I-SRBC) in liver and spleen were determined at 1 and 48 h after hemorrhage. No significant changes in the uptake or catabolism of SRBC in liver or spleen were found at 1 h after hemorrhage and resuscitation with any of the fluids. However, at 48 h a significant increase in liver uptake of SRBC was seen in animals resuscitated with either Haemaccel or HES compared to that in animals resuscitated with shed blood or in animals subjected to a sham operation. The increase in liver uptake was accompanied by a small decrease in spleen uptake in animals resuscitated with Haemaccel but not with HES. No great changes in catabolic activity were seen at 48 h, although activity levels tended to be higher in animals resuscitated with Haemaccel. Separate groups of animals were challenged by an intraperitoneal injection with live Escherichia coli at 1 or 48 h after hemorrhage and resuscitation. Sixty-four percent of the animals resuscitated with shed blood survived the challenge with E. coli at 1 h after hemorrhage, whereas only 10 and 0% survival was seen for animals resuscitated with Haemaccel and HES, respectively. At 48 h survival was 80% for shed-blood-resuscitated animals and 60 and 70% for Haemaccel- and HES-resuscitated animals, respectively. 相似文献
74.
Leukotriene B4 Receptor (BLT-1) Modulates Neutrophil Influx into the Peritoneum but Not the Lung and Liver during Surgically Induced Bacterial Peritonitis in Mice 下载免费PDF全文
Melanie J. Scott William G. Cheadle J. Jason Hoth James C. Peyton Krishnaprasad Subbarao Wen-Hai Shao Bodduluri Haribabu 《Clinical and Vaccine Immunology : CVI》2004,11(5):936-941
Leukotriene B4 (LTB4) is a rapidly synthesized, early neutrophil chemoattractant that signals via its cell surface receptor, BLT-1, to attract and activate neutrophils during peritonitis. BLT-1-deficient (BLT-1−/−) mice were used to determine the effects of LTB4 on neutrophil migration and activation, bacterial levels, and survival after cecal ligation and puncture (CLP). Male BLT-1−/− or wild-type (WT) BALB/c mice underwent CLP. Tissues were harvested for determination of levels of bacteria, myeloperoxidase (MPO), LTB4, macrophage inflammatory protein 2 (MIP-2), and neutrophil (polymorphonuclear leukocyte [PMN]) numbers at 4 and 18 h after CLP. PMN activation was determined by an assessment of phagocytosis ability and CD11b expression. Survival was also determined. BLT-1−/− mice had decreased numbers of PMNs in the peritoneum at both 4 and 18 h after CLP but increased numbers of PMNs in the blood at 18 h compared with WT mice. Liver and lung MPO levels were significantly higher in BLT-1−/− mice at both 4 and 18 h after CLP, with increased bacterial levels in the blood, the liver, and peritoneal fluid at 4 h. Bacterial levels remained higher in peritoneal fluid at 18 h, but blood and liver bacterial levels at 18 h were not different from levels at 4 h. PMN phagocytosis and CD11b levels were decreased in BLT-1−/− mice. LTB4 levels were similar between the groups before and after CLP, but MIP-2 levels were decreased both locally and systemically in BLT-1−/− mice. Survival was significantly improved in BLT-1−/− mice (71%) compared with WT mice (14%) at 48 h post-CLP. Thus, LTB4 modulates neutrophil migration into the mouse peritoneum, but not the lung or liver, after CLP. Despite higher bacterial and PMN levels at remote sites, there was increased survival in BLT-1−/− mice compared to WT mice. Decreased PMN activation may result in less remote organ dysfunction and improved survival. 相似文献
75.
Hera Der-Sarkissian Catherine Bonaïti-Pellié Marie-Louise Briard-Guillemot Jean-Michel Zucker 《Cancer Genetics and Cytogenetics》1982,7(1):73-77
Spontaneous and mitomycin C(MMC)-induced sisyer chromatid exchanges were studied in 11 patients with retinoblastoma and 7 normal controls. Spontaneous rates were similar in patients and in controls. The MMC-induced rate was found to be significantly higher in bilaterally affected patients than in controls. It is suggested that this increase may be due to a DNA repair deficiency. However, it is not possible to clarify wether this abnormality is associated with the retinoblastoma gene or with another factor acting on the degree of expressivity of the disease in gene carriers. 相似文献
76.
Stoltenberg SF Twitchell GR Hanna GL Cook EH Fitzgerald HE Zucker RA Little KY 《American journal of medical genetics》2002,114(2):230-234
A functional polymorphism in the regulatory region of the serotonin transporter gene (5-HTTLPR) is considered to be a plausible candidate gene for anxiety-related personality traits and for alcoholism. Empirical support for the association between 5-HTTLPR and psychological traits has been somewhat inconsistent; however, observations of the functional dominance of the low-activity s-allele over the l-allele have been more consistent. When studying the influence of particular genes on psychological traits, it seems useful also to assess more biological intermediate traits that may mediate the effects of those genes on the traits of interest. The present study examined relationships between 5-HTTLPR genotype, whole blood serotonin (5-HT) level, and platelet 5-HT binding in 150 Caucasian subjects from 50 biological families. Individuals with the s-allele had lower average platelet 5-HT binding availability than those with the l/l genotype (P<0.025). Whole blood 5-HT level was not associated with 5-HTTLPR genotype. In adult men, those with the s-allele had higher mean scores on the NEO-FFI personality trait of openness than did those with the l/l genotype (P=0.002). The effect was not statistically significant in women (P=0.42), although it was in the same direction. Our findings do not support an association of 5-HTTLPR genotype with alcoholism diagnosis, alcoholism subtype, or the personality trait of neuroticism. The results of this pilot study suggest that further work should examine the mediation of the genetic effects on personality traits by biochemical measures and their moderation by gender. 相似文献
77.
Janine Jason Lennox K. Archibald Okey C. Nwanyanwu Anne L. Sowell Ian Buchanan Joshua Larned Michael Bell Peter N. Kazembe Hamish Dobbie William R. Jarvis 《Clinical and Vaccine Immunology : CVI》2002,9(3):616-621
In animal studies, vitamin A deficiency induces a shift from type 2 (humoral) to type 1 (cellular) cytokines; there are no similar data for humans. Control of human immunodeficiency virus (HIV) and Mycobacterium tuberculosis infections requires type 1 cytokine (cellular) immunity. These infections and vitamin A deficiency are highly prevalent in Africa. We therefore examined the interactions among serum vitamin A levels, immune parameters, HIV infection status, Mycobacterium bovis BCG vaccine scarring (as an indicator of a type 1 cytokine profile), and clinical findings for 70 hospitalized children in Malawi, Africa. Directly conjugated monoclonal antibodies and flow cytometry were used to assess cell-specific cytokine production by peripheral blood monocytes and lymphocyte subpopulations. The statistical techniques employed included nonparametric statistics and logistic regression analyses. Thirty percent of the participants had severe vitamin A deficiency (<10 μg/dl), 34% had moderate deficiency (10 to <20 μg/dl), and 36% had normal levels (≥20 μg/dl). Vitamin A levels were lower for HIV-positive than for HIV-negative children (median, 10 and 17 μg/dl, respectively). Vitamin A-deficient children (<20 μg/dl) were more likely than non-vitamin A-deficient children to have higher proportions of natural killer (NK) cells (median, 8.3 and 5.2%, respectively) and lower ratios of interleukin-10-producing monocytes to tumor necrosis factor alpha-producing monocytes after induction (median, 1.0 and 2.3, respectively). Vitamin A-deficient children were also more likely than non-vitamin A-deficient children to exhibit respiratory symptoms (47% versus 12%) and visible BCG vaccine scars (83% versus 48%), which are indicative of a type 1 response to vaccination. Vitamin A status did not vary with gender, age, incidence of malaria parasitemia, blood culture positivity, or rates of mortality (6% of vitamin A-deficient children died versus 20% of non-vitamin A-deficient children). Lower vitamin A levels were associated with a relative type 1 cytokine dominance and proportionately more NK cells, both of which may be somewhat beneficial to persons who are exposed to HIV, M. tuberculosis, or other type 1 pathogens. 相似文献
78.
Zucker B Luthi-Carter R Kama JA Dunah AW Stern EA Fox JH Standaert DG Young AB Augood SJ 《Human molecular genetics》2005,14(2):179-189
79.
Candida albicans and Saccharomyces cerevisiae expressing the adhesins Als5p or Als1p adhere to immobilized peptides and proteins that possess appropriate sequences of amino acids in addition to a sterically accessible peptide backbone. In an attempt to further define the nature of these targets, we surveyed the ability of yeast cells to adhere to 90- micro m-diameter polyethylene glycol beads coated with a 7-mer peptide from a library of 19(7) unique peptide-beads. C. albicans bound to ca. 10% of beads from the library, whereas S. cerevisiae expressing Als5p or Als1p bound to ca. 0.1 to 1% of randomly selected peptide-beads. S. cerevisiae expressing Als1p had a distinctly different adherence phenotype than did cells expressing Als5p. The former adhered in groups or clumps of cells, whereas the latter adhered initially as single cells, an event which was followed by the build up of cell-cell aggregates. Beads with adherent cells were removed, and the peptide attached to the bead was determined by amino acid sequencing. All adhesive beads carried a three-amino-acid sequence motif (tau phi+) that possessed a vast combinatorial potential. Adherence was sequence specific and was inhibited when soluble peptide identical to the immobilized peptide was added. The Als5p adhesin recognized some peptides that went unrecognized by Als1p. The sequence motif of adhesive peptides identified by this method is common in proteins and offers so many possible sequence combinations that target recognition by the Als proteins is clearly degenerate. A degenerate recognition system provides the fungi with the potential of adhering to a multitude of proteins and peptides, an advantage for any microorganism attempting to establish a commensal or pathogenic relationship with a host. 相似文献
80.
We examined how family and child risk factors jointly affected stability and change in externalizing behavior over time in a prospective study of eventual alcohol use disorder. Study participants were community-recruited alcoholic and control families, and their initially preschool-aged male and female children (N = 335). Family risk varied as a function of both parental alcoholism (ALC) and antisocial personality disorder (ASPD) and was evaluated for both parents. Child risk was characterized by a set of risky temperament attributes pertaining to high activity, high reactivity, and low attention span. Externalizing behavior was used as the proxy indicator for later alcohol problems. For children in the high family risk group (involving current ALC in both parents or current ALC + ASPD comorbidity or both), child risk when children were 3-5 years old (Wave 1) directly predicted externalizing behavior when children were 6-8 years old (Wave 2), even when Wave 1 child risk was controlled for. In addition, parents' negative interaction with children at Wave 1 mediated the effect of child risky temperament on Wave 2 externalizing behavior. No such pattern was observed in the low family risk group, where only autostability effects were predictive of outcomes at Wave 2. The importance of nesting structure as an ingredient in the epigenesis of risk was discussed. Its particular relevance in understanding the process of risk transmission among offspring from antisocial alcoholic families was emphasized. 相似文献