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991.
992.
Diabetic patients have a higher rate of mortality from sepsis than do their nondiabetic septic counterparts. The hypothesis
in this study is that chronic diabetes may make cardiovascular systems more sensitive to septicemia. To test this hypothesis,
the authors investigated the effect of diabetes on endotoxin-induced cardiac toxicity. Diabetes was induced in FVB mice by
injecting a single dose (150 mg/kg) of streptozotocin. Two months after streptozotocin treatment, the diabetic mice were treated
with lipopolysaccharide by intraperitoneal injection at 2 mg/kg. Cardiac toxicity was evaluated by measuring levels of serum
cardiac enzymes and cardiac morphology at 1 h, 4.5 h, and 24 h after lipopolysaccharide treatment. Serum and cardiac tumor
necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were detected by enzyme-linked immunosorbent assay methods at 1 h and 4.5
h after lipopolysaccharide treatment. Lipopolysaccharide treatment did not significantly affect the diabetic manifestations,
including decreased body weight gain and increased glycated hemoglobin and serum triglyceride levels. However, diabetes significantly
enhanced lipopolysaccharide-induced cardiac toxicity, which was demonstrated by significant increases in the levels of cardiac
enzymes such as creatine phosphokinase and troponin T, abnormal morphological changes examined under light microscope with
hematoxylin and eosin staining, and oxidative damage to proteins detected by 3-nitrotyrosine staining. Lipopolysaccharide
treatment significantly increased serum and cardiac TNF-α and IL-6 concentrations. Diabetes did not alter the effect of lipopolysaccharide
on serum and cardiac TNF-α elevation, but it significantly enhanced lipopolysaccharide-induced cardiac IL-6 production. These
results suggest that diabetes significantly enhances endotoxin-induced cardiac toxicity, possibly through mechanisms that
involve inflammatory/acute-phase cytokines. 相似文献
993.
Hubert Maes Henryk Taper Carlo Cocito 《Journal of cancer research and clinical oncology》1996,122(5):296-300
Preparations of live or lysates ofMycobacterium bovis strain Calmette-Guérin (BCG) have long been used as treatments for a variety of cancer types, especially those involving the urinary tract, with varying success. This study was conducted to compare the antitumoral activity of BCG and the thermostable macromolecular antigen complex of BCG (A60) when used as preventive treatments, in conjunction with or without tumor antigens, against growth and dissemination of the EMT6 murine tumor cell line. It was demonstrated that tumor antigens alone did not significantly alter the oncological indexes, although a slight increase in both T lymphocyte and macrophage activations was found. It was further demonstrated that A60 induces a protective activity up to 40% greater than that of live BCG and that this protection was not accompanied by any of the adverse effects sometimes observed during BCG immunotherapy.Abbreviations BCGMycobacterium bovis
strain Calmette-Guérin
-
A60
the thermostable macromolecular antigen complex ofM. bovis BCG
-
EMT6
murine transplantable mammary adenocarcinoma
-
ELISA
enzyme-linked immunosorbent assay 相似文献
994.
Clarke JL Vulliamy TJ Roper D Mesbah-Namin SA Wild BJ Walker JI Will AM Bolton-Maggs PH Mason PJ Layton DM 《Blood cells, molecules & diseases》2003,30(3):258-263
Glucosephosphate isomerase (GPI) deficiency in humans is an autosomal recessive disorder, which results in nonspherocytic hemolytic anemia of variable clinical expression. A 4-year-old female with severe congenital hemolytic anemia had low red cell GPI activity of 15.5 IU/g Hb (50% of normal mean) indicating GPI deficiency. Subsequent DNA sequence analysis revealed a novel homozygous 921C to G mutation in the GPI gene sequence, predicting a Phe307 to Leu replacement. Strikingly, the red cell GPI activity in this patient was higher than that found in a second patient expressing the same GPI variant, with a more severe clinical phenotype. We propose that the hemolysis in the first patient may be modified by an accompanying deficiency of glucose-6-phosphate dehydrogenase (G6PD). The proband's red cell G6PD activity was reduced at 4.5 IU/g Hb (50% of normal mean) and molecular studies revealed heterozygosity for the G6PD Viangchan mutation and a skewed pattern of X-chromosome inactivation, producing almost exclusive expression of the mutated allele. The G6PD Viangchan variant is characterised by severe enzyme deficiency, but not chronic hemolysis. This study suggests that the metabolic consequences of a combined deficiency of GPI and G6PD might be responsible for a different clinical outcome than predicted for either defect in isolation. 相似文献
995.
目的 观察急性心肌梗死(AMI)患者人院外周血白细胞(WBC)总数、血浆白细胞介素-6(IL-6)对近期预后的影响。方法 首发AMI患者103例,通过检测WBC、IL-6,以发病后30天内是否发生心血管不良事件(包括心源性死亡、心力衰竭、心源性休克、恶性心律失常)为观察终点。结果 36例发生心血管事件组外周血WBC总数和IL-6显著高于67例无心血管事件组。AMI时外周血WBC总数和IL-6水平为发生心血管事件的预测因素。结论 WBC、IL-6与AMI患者近期预后相关。 相似文献
996.
目的 调查贵州省江口土家族男性葡萄糖-6-磷酸脱氢酶(G6PD)缺陷症的基因频率。方法 2002年10-11月随机选取227名江口当地土家族男性居民,采用四氮唑蓝(NBT)纸片定性法初筛G6PD缺陷症。G6PD/6PGD比值法定量确诊。结果 对贵州省江口县227名土家族男性进行筛查,共检出17例G6PD缺陷阳性。其基因频率为0.0749。结论 通过对贵州土家族G6PD缺乏症基因频率的调查和分析,初步了解了贵州省土家族G6PD缺乏症的分布特征。为该地区预防该疾病、指导临床、提高少数民族的素质及研究该民族起源提供了一定的依据。 相似文献
997.
AIM: To assess the synergistic action of famotidine (FMD) and chlorpheniramine (CPA) on acetic acid-induced chronic gastric ulcer in rats. METHODS: Chronic gastric lesions were induced in male Sprague-Dawley (SD) rats by serosal application of the acetic acid. Forty SD rats were randomly divided into blank group (n=8), control group (n=8), FMD group (n = 8), CPA group (n=8), and FMD+CPA group (n=8). Each group was given intraperitoneally (i.p.) 0.5 mL/100 g distilled water, 9 g/L NaCl saline, 4 mg/kg FMD, 10 mg/kg CPA, 4 mg/kg FMD+10 mg/kg CPA, respectively, daily for 10 d. On d 10, ulcer area was determined by planimetry. The level of myeloperoxidase (MPO) in the liver homogenation was determined by biochemical methods and the plasma levels of 6-ketoprostaglandin F1 alpha (6-keto-PGFia) and IL-8 were determined by radioimmunoassay. RESULTS: The synergistic effects of FMD+CPA group on the lesion, IL-8, 6-keto-PGFia and MPO were confirmed. The effect of FMD+CPA group was significantly different as compared to the control and FMD groups. The lesion (mm2) was reduced from 40.18±2.6 in control group to 6.83±2.97 in PMD+CPA group, P<0.01, and from 32.9±3.27 in FMD group to 6.83±2.97 in PMD+CPA group, P<0.01. The plasma levels of IL-8 decreased from 0.69±0.11 ng/L in control group to 0.4±0.04 ng/L in PMD+CPA group, P<0.01, and from 0.51±0.08 ng/L in FMD group to 0.4±0.04 ng/L in PMD+CPA group, P<0.05. The level of 6-keto-PGFia increased from 7.55±1.65 ng/L in control group to 16.62±0.97 ng/L in PMD+CPA group, P<0.01, and from 13.15±1.48 ng/L in FMD group to 16.62±0.97 ng/L in PMD+CPA group, P<0.05. The levels of MPO in the liver homogenate decreased from 9.12±2.05 u/L in control group to 4.33±0.95 u/L in PMD+CPA group, P<0.01, and from 8.3±1.29 u/L in FMD group to 4.33±0.95 u/L, P<0.01. CONCLUSION: The synergistic action of FMD and CPA on acetic acid-induced chronic gastric ulcer in rats decreases the incidence of ulcer and also enhances the healing of ulcer. 相似文献
998.
Frances M. Sobierajski Graeme M. Purdy Charlotte W. Usselman Rachel J. Skow Marina A. James Radha S. Chari Rshmi Khurana Michael K. Stickland Sandra T. Davidge Maureen Devolin Craig D. Steinback Margie H. Davenport 《The Canadian journal of cardiology》2018,34(4):485-491
Background
Cardiovagal baroreflex gain (cBRG) reflects an individual's ability to buffer swings in blood pressure. It is not well understood how this mechanism is influenced by physical activity in pregnancy. Because pregnant women tend to engage in low levels of moderate-to-vigorous physical activity (MVPA) and high levels of sedentary behaviour, we sought to determine the influence of MVPA and sedentary behaviour on cBRG and mean arterial pressure (MAP) in pregnancy.Methods
Fifty-eight third trimester (31.9 ± 3.0 weeks) normotensive pregnant women (31.2 ± 2.8 years) were tested. Heart rate (electrocardiogram) and blood pressure (systolic blood pressure and MAP; finger photoplethysmography) were collected on a beat-by-beat basis, and averaged over 3 minutes of rest. Spontaneous cBRG was calculated as the slope of the relationship between fluctuations in systolic blood pressure and heart rate. Objective measures of MVPA and sedentary behaviour were collected over a 7-day period using an ActiGraph accelerometer (model wGTX3-BT; ActiGraph LLC, Pensacola, FL).Results
Participants spent 67.5 ± 7.9% of waking hours engaged in sedentary behaviour, and performed 68.6 ± 91.9 minutes of MVPA per week. Sedentary behaviour was not related to cBRG (r = ?0.035; P = 0.793) or MAP (r = ?0.033; P = 0.803). However, MVPA was positively associated with cBRG (r = 0.315; P = 0.016), but not MAP (r = ?0.115; P = 0.389). The association between MVPA and cBRG remained significant after controlling for age, pre-pregnancy body mass index, gestational age, and wear time (r = 0.338; P = 0.013), indicating that women who engaged in greater amounts of MVPA showed increased cBRG.Conclusions
Our data suggest that increased MVPA, but not necessarily reduced sedentary behaviour, might be beneficial for reflex control of blood pressure during pregnancy. 相似文献999.
Maria Domenica Cappellini Maurizio Sampietro Daniela TonioloGiovanni Carandina Salvatore Pittalis Franco Martinez di Montemuros Dario Tavazzi Gemino Fiorelli 《British journal of haematology》1994,87(1):209-211
Summary. A new glucose-6-phosphate dehydrogenase variant detected in an Italian man from the Po delata is described and designated as G6PD Modena. Biochemical characterization of the variant enzyme revealed an activity 21% of normal, a slow electrophoretic mobility, increased Km value for NADP, decreased Km value for G6P and a complete absence of NADPH inhibition, which could account for the apparently nonhaemolytic feature of this variant. The cloning and sequencing of the G6PD Modena allele showed a GC transition at nucleotide 844 in exon VIII causing a Asp His amino acid substitution. On the basis of biochemical characterization, G6PD Modena is classified as a genuine variant but it has the same mutation as G6PD Seattle-like. 相似文献
1000.
Colbert LH Visser M Simonsick EM Tracy RP Newman AB Kritchevsky SB Pahor M Taaffe DR Brach J Rubin S Harris TB 《Journal of the American Geriatrics Society》2004,52(7):1098-1104
OBJECTIVES: To examine the association between physical activity and inflammatory markers, with consideration for body fatness and antioxidant use. DESIGN: Cross-sectional study, using baseline data from the Health, Aging and Body Composition Study. SETTING: Metropolitan areas surrounding Pittsburgh, Pennsylvania, and Memphis, Tennessee. PARTICIPANTS: Black and white, well-functioning men and women (N=3,075), aged 70 to 79. MEASUREMENTS: Interviewer-administered questionnaires of previous-week household, walking, exercise, and occupational/volunteer physical activities. Analysis of covariance was used to examine the association between activity level and serum C-reactive protein (CRP), interleukin-6 (IL-6), and plasma tumor necrosis factor alpha (TNFalpha) with covariate adjustment. Antioxidant supplement use (multivitamin, vitamins E or C, beta carotene) was evaluated as an effect modifier of the association. RESULTS: Higher levels of exercise were associated with lower levels of CRP (P<.01), IL-6 (P<.001), and TNFalpha (P=.02) (e.g., CRP=1.95 mg/L for no exercise and 1.72 for >180 min/wk). Adjustment for body fatness attenuated the associations somewhat. Use of antioxidant supplements modified the CRP (P(interaction)=.01) and IL-6 (P(interaction)=.08) associations such that concentrations were low in those taking supplements (e.g., CRP=1.79-1.84 across exercise levels) and higher in nonsupplement users who did no exercise (2.03) than in those who did the most (1.72). Among nonexercisers, higher levels of other physical activity were related to lower levels of CRP (P<.01) and IL-6 (P=.02) but not TNFalpha (P=.36), even after accounting for body fat. CONCLUSION: Inflammatory markers are lower in older adults with higher levels of exercise and nonexercise activity and in antioxidant supplement users regardless of exercise level. 相似文献