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51.
Giacco R Clemente G Luongo D Lasorella G Fiume I Brouns F Bornet F Patti L Cipriano P Rivellese AA Riccardi G 《Clinical nutrition (Edinburgh, Scotland)》2004,23(3):331-340
BACKGROUND: The intake of 10 g/day of short-chain-fructo-oligosaccharides (sc-FOS) has been shown to increase significantly bifidus counts and to produce high amounts of short-chain fatty acids (SCFA), presumed to influence glucose and lipid metabolism. AIM: To evaluate the effects of moderate intake of sc-FOS on glucose and lipid metabolism in individuals with mild hypercholesterolaemia. Design: A randomized double-blind sequential cross-over study. SUBJECTS AND METHODS: Thirty subjects of both genders (20 M/10 F), mean age 45.5+/-9.9 years (M+/-SD), BMI 26.6+/-2.2 kg/m(2), with plasma cholesterol >5.17 and <7.76 mmol/l and plasma triglycerides <3.45 mmol/l, participated in the study. The study was performed after a wash-out period of 1 month and a run-in period of 1 month to stabilize patients on a standard diet (CHO 50%, fat 30%, protein 20%, fibre 20 g/day) plus placebo (maltodextrine plus aspartame 15 g/day). At the end of run-in, subjects were randomly assigned to receive sc-FOS (Actilight) (10.6g/day) or placebo (maltodextrine plus aspartame 15 g/day) with tea and/or coffee for a duration of 2 months and thereafter switched to the other treatment for additional 2 months. Plasma glucose, total and lipoprotein (VLDL, LDL, HDL) cholesterol and triglyceride concentrations were measured in the fasting state at the end of run-in and of each treatment period. At the end of the two treatment periods, patients consumed a standard test meal (protein 15%, carbohydrate 34%, fat 51%, kJ 3988) 1h after the administration of 5.3g of sc-FOS or placebo; plasma glucose, insulin, free fatty acid (FFA) and triglyceride responses to the test meal were evaluated. RESULTS: No significant difference in fasting parameters was detected between the two treatments. After sc-FOS and placebo plasma cholesterol levels were, respectively, 6.47+/-0.70 and 6.44+/-0.78 mmol/l (n.s.) and plasma triglycerides were 1.53+/-0.71 and 1.56+/-0.53 mmol/l (n.s.). No significant differences were observed in cholesterol and triglyceride content of VLDL, LDL and HDL and in plasma Apo A1 levels; conversely, fasting plasma Lp(a) concentrations were significantly increased after sc-FOS (37+/-38 vs. 33+/-35 mg/dl; P<0.005). Postprandial responses of glucose, FFA and triglycerides were not significantly different between sc-FOS and placebo, while postprandial insulin response (incremental area) was significantly reduced after sc-FOS compared to placebo (14,490+/-7416 vs. 17,760+/-7710 pmol/l x 300 min; P<0.02). CONCLUSIONS: A moderate intake of sc-FOS has no major effects on lipid metabolism, both in the fasting and in the postprandial period, in individuals with mild hypercholesterolaemia. A small but significant increase of Lp(a) concentrations was observed with sc-FOS consumption together with a reduction of the postprandial insulin response; however, the clinical relevance of these small effects is unclear. 相似文献
52.
Adriaensen D Brouns I Van Genechten J Timmermans JP 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2003,270(1):25-40
Innervated groups of neuroendocrine cells, called neuroepithelial bodies (NEBs), are diffusely spread in the epithelium of intrapulmonary airways in many species. Our present understanding of the morphology of NEBs in mammalian lungs is comprehensive, but none of the proposed functional hypotheses have been proven conclusively. In recent reviews on airway innervation, NEBs have been added to the list of presumed physiological lung receptors. Microscopic data on the innervation of NEBs, however, have given rise to conflicting interpretations. Using neuronal tracing, denervation, and immunostaining, we recently demonstrated that the innervation of NEBs is much more complex than the almost unique vagal nodose sensory innervation suggested by other authors. The aim of the present work is to summarize our present understanding about the origin and chemical coding of the profuse nerve terminals that selectively contact pulmonary NEBs. A thorough knowledge of the complex interactions between the neuroendocrine cells and at least five different nerve fiber populations is essential for defining the position(s) of NEBs among the many pulmonary receptors characterized by lung physiologists. 相似文献
53.
54.
Prevalence of risk factors for cardiovascular disease in Canadians 55 to 74 years of age: results from the Canadian Heart Health Surveys, 1986-1992 总被引:1,自引:1,他引:0 下载免费PDF全文
DB Langille MR Joffres KM MacPherson P Andreou SA Kirkland DR MacLean 《Canadian Medical Association journal》1999,161(8):S3-S9
BACKGROUND: By 2016, the proportion of Canadians older than 65 years of age will increase to 16%, and there will be an increase in the absolute number of cases of cardiovascular disease in older Canadians. The Canadian Heart Health Surveys database provides information about this population upon which health policy related to cardiovascular disease can be based. This paper presents for the first time population-based data on the risk factors for cardiovascular disease in older Canadians. METHODS: Canadians from all 10 provinces participated in surveys of cardiovascular risk factors; health insurance registries were used as sampling frames. In each province, probability samples of 2200 adults 18 to 74 years old not living in institutions, on reserves or in military camps were asked to participate in interviews and to undergo testing at clinics for major risk factors for cardiovascular disease. RESULTS: A total of 2739 men (response rate 70%) and 2617 women (response rate 66%) aged 55 to 74 years participated in the survey and also provided follow-up clinical measurements at the clinic. Overall, 52% of participants were hypertensive, 26% had isolated systolic hypertension, and 30% had a total blood cholesterol level of 6.2 mmol/L or greater. Rates of current smoking were lower in women than men (17% v. 22%). Overall, 87% of men and 78% of women who were current smokers smoked at least 10 cigarettes per day. Only slightly more than half of participants exercised at least once a week for at least 15 minutes, and almost half had a body mass index of 27 or greater. In only 4% was no major risk factor for cardiovascular disease detected. INTERPRETATION: Significant numbers of older Canadians have one or more major risk factors for cardiovascular disease. Many of these risk factors are amenable to modification. 相似文献
55.
成人型胆管囊肿及其合并症的超声与核磁及胰胆管水成像诊断 总被引:4,自引:0,他引:4
目的 探讨成人胆管囊肿及其合并症的超声、核磁及胰胆管水成像 (MR/ MRCP)的影像表现。方法 选取胆管扩张病例进行超声及核磁检查 ,观察胆胰管内径、胆管扩张形态、管壁厚度、回声 ,并进行彩色多普勒血流检测及核磁胰胆管水成像 (MR/ MRCP)检查 ,两者结果与术后病理对照。结果 经手术证实胆管囊肿 2 0例 ,包括 :Caroli's病 2例 , 型胆总管囊肿 14例 ,呈囊性、梭形、圆柱形扩张 ;肝门部胆管囊肿 (囊肿型 ) 3例 ,胆总管上段憩室 1例 ( 型 )。合并胆囊结石 10例 ,肝内胆管、胆总管结石 8例 ;合并肝局灶性炎 3例 ,肝脓肿 1例 ;合并癌变 5例 (高、低分化腺癌 3例 ,黏液腺癌 1例 ,类癌 1例 ) ;共同管过长 (>1.5 cm) 6例。超声与 MRCP对胆管囊肿全部诊断。合并症中超声对炎变、结石、癌变诊断分别为 95 % ,10 0 % ,95 % ,而 MRCP/MR为 10 0 % ,90 % ,95 %。超声对结石、癌变及管壁的微细结构观察优于 MRCP,MRCP对胆管全程显示优于超声 ,结合平扫及增强扫描诊断炎变符合率 10 0 %。结论 超声与 MR成像在成人胆管囊肿及其合并症中的诊断意义重大 ,联合应用有利于对该病的全面认识 ,便于指导临床。 相似文献
56.
The bias favoring deletion over inversion in DH-JH rearrangement has been
known for years, but the underlying mechanism has yet to be fully defined.
It has been suggested that the ratio of deletion/inversion is determined by
the combined effect of two factors: (i) the relative strengths of 5' and 3'
recombination signal sequences (RSS) of a DH segment, and (ii) the
efficiency with which the deletional product (one joint) forms relative to
the inversional product (two joints). In this study, we analyzed for the
first time the effect of factor 1 alone on the biased 3' RSS utilization in
DH-JH joining by using deletional plasmids in an extrachromosomal substrate
V(D)J recombination assay. It was found that the 3' RSS and associated
coding end (12 bp) mediate recombination more efficiently than the 5'
RSS/coding end DH-JH plasmids. These results demonstrate that the effect of
the RSS/coding end alone can account, at least partially, for the
predominant deletion in DH-JH recombination. The potential effect of the
relative strength of RSS and associated coding end on the ordered
rearrangement of DH-JH followed by VH to DH-JH was also assessed. When
recombination frequencies of D-->J (3' DH to J3) were compared with
frequencies of V-- >D (VHPJ14 to 3' DH or VHOX2 to 3' DH), it was found
that V-->D joining was, if anything, more efficient than D-->J
joining. Therefore, if all three segments were accessible, RSS/coding end
effects would not contribute to the ordered rearrangement of the IgH locus.
相似文献
57.
Williamson MR; Boyd CM; McGuire EL; Angtuaco T; Westbrook KC; Lang NP; Alston J; Broadwater JR; Navab F; Bersey ML 《Radiology》1986,159(1):272-273
The nuclear medicine bleeding scan is frequently insufficient to locate sites of bleeding precisely, in spite of its great sensitivity. A small, hand-held Geiger-Müller counter, placed directly on exposed intestine in the operating room, enables precise location of the probable bleeding site. In three patients, the technique allowed a minimal amount of intestine to be resected, distinguished between large- and small-intestinal hemorrhage, and eliminated other foci as sites of bleeding. 相似文献
58.
A Bahrami Y Rassi N Maleki MA Oshaghi M Mohebali MR Yagoobi-Ershadi S Rafizadeh 《亚太热带病杂志(英文版)》2014,4(2):110-114
Objective
To identify the vector(s), the parasite and the species composition of sand flies in the district during May-October 2012.Methods
For reaching our objectives we used polymerase chain reaction of kDNA, ITS1-rDNA, followed by restriction fragment length polymorphism.Results
Two species of Phlebotomus sergenti and Phlebotomus tobbi were the most prevalent among 8 species identified comprising 51.1% and 32.9% respectively. Among the 160 specimens of female sand flies tested by polymerase chain reaction of kDNA, ITS1-rDNA, followed by restriction fragment length polymorphisms, only 1 out of 80 Phlebotomus tobbi (1.25%) were positive to Leishmania infantum parasites.Conclusions
Our finding showed that Phlebotomus tobbi may play as a vector to circulate the parasite of Leishmania infantum among reservoir(s) and human. 相似文献59.
Polymorphisms in genes related to folate and cobalamin metabolism and the associations with complex birth defects 总被引:1,自引:0,他引:1
Brouns R Ursem N Lindemans J Hop W Pluijm S Steegers E Steegers-Theunissen R 《Prenatal diagnosis》2008,28(6):485-493
OBJECTIVE: To investigate the associations between biomarkers and genetic variants involved in homocysteine metabolism and the risk of complex birth defects. METHODS: Total homocysteine (tHcy), folate, cobalamin, apo-transcobalamin (apo-TC) and apo-haptocorrin (apo-HC) were measured in the amniotic fluid of 82 women who were pregnant with a child having a complex birth defect, such as neural tube defect, cleft lip and/or palate, heart defect or omphalocele, and in 110 women pregnant with a non-malformed child. The determined genotypes of the child comprised of 5, 10-methylenetetrahydrofolate reductase (MTHFR 677C > T, 1298A > C), methionine synthase (MTR 2756A > G), methionine synthase reductase (MTRR 66A > G) and transcobalamin (TCN2 776C > G). Univariate and multivariate logistic regression analyses were performed. RESULTS: Significantly lower cobalamin and higher apo-TC, apo-HC, tHcy and folate concentrations were determined in amniotic fluids of cases compared with controls (p< or =0.001). Logistic regression analysis revealed that after adjustment for maternal age, children carrying the MTHFR 677T allele showed a four-fold increased risk of having a complex birth defect, OR (95% CI) = 4.0 (1.1-15.4). Other genotypes did not show significant associations. CONCLUSION: The MTHFR 677C > T polymorphism in conjunction with reduced folate- and/or cobalamin status may increase the risk of complex birth defects. 相似文献
60.
Liu SC; Palek J; Yi SJ; Nichols PE; Derick LH; Chiou SS; Amato D; Corbett JD; Cho MR; Golan DE 《Blood》1995,86(1):349-358
Southeast Asian ovalocytosis (SAO) is an asymptomatic trait characterized by rigid, poorly deformable red cells that resist invasion by several strains of malaria parasites. The underlying molecular genetic defect involves simple heterozygous state for a mutant band 3 protein, which contains a deletion of amino acids 400 through 408, linked with a Lys 56-to-Glu substitution (band 3-Memphis polymorphism). To elucidate the contribution of the mutant SAO band 3 protein to increased SAO red blood cell (RBC) rigidity, we examined the participation of the mutant SAO band 3 protein in increased band 3 attachment to the skeleton and band 3 oligomerization. We found first that SAO RBC skeletons retained more band 3 than normal cells and that this increased retention preferentially involved the mutant SAO band 3 protein. Second, SAO RBCs contained a higher percentage of band 3 oligomer-ankyrin complexes than normal cells, and these oligomers were preferentially enriched by the mutant SAO protein. At the ultrastructural level, the increased oligomer formation of SAO RBCs was reflected by stacking of band 3-containing intramembrane particles (IMP) into longitudinal strands. The IMP stacking was not reversed by treating SAO RBCs in alkaline pH (pH 11), which is known to weaken ankyrin-band 3 interactions, or by removing the cytoplasmic domain of band 3 from SAO membranes with trypsin. Finally, we found that band 3 protein in intact SAO RBCs exhibited a markedly decreased rotational mobility, presumably reflecting the increased oligomerization and the membrane skeletal association of the SAO band 3 protein. We propose that the mutant SAO band 3 has an increased propensity to form oligomers, which appear as longitudinal strands of IMP and exhibit increased association with membrane skeleton. This band 3 oligomerization underlies the increase in membrane rigidity by precluding membrane skeletal extension, which is necessary for membrane deformation. 相似文献