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131.
E. Rigotti G. L. Piacentini M. Ress R. Pigozzi A. L. Boner D. G. Peroni 《Clinical and experimental allergy》2006,36(5):614-618
BACKGROUND: Precise relationship between breastfeeding and infant allergy is poorly understood. Objective Aim was to quantify TGF-beta(1) and IL-10 in colostrum and mature milk from allergic and non-allergic mothers and to verify relationship with allergic disease development. METHODS: Mothers (13 allergics, nine controls) of 22 newborns participated to prospective study on development of children atopy. Colostrum and mature milk were assayed for TGF-beta(1) and IL-10 by ELISA. Children underwent paediatrician evaluation at 6 months of life. RESULTS: Data are presented as median values and range. A significant difference in concentration of TGF-beta(1) between colostrum (330, range 0-3400 pg/mL) and mature milk (215, range 0-2400 pg/mL) was observed in samples from allergic mothers (P=0.015). In mature milk TGF-beta(1) was significantly lower in allergic (215, range 0-2400 pg/mL) than in non-allergic mothers (1059, range 0-6250 pg/mL) (P=0.015). IL-10 was weakly expressed without significant differences between allergic (4.8, range 0-42 and 9.5, range 0-42 pg/mL in colostrum and in mature milk) and non-allergic mothers (0, range 0-42 pg/mL in colostrum and 0, range 0-42 pg/mL in mature milk). After 6 months 46% infants from allergic mothers, but none from controls, presented atopic dermatitis. CONCLUSION: TGF-beta(1) was significantly less secreted in mature milk of allergic mothers, while no difference in IL-10 was found. Particular cytokine patterns in milk could influence development of atopic diseases. Further immunological studies in this field are necessary. 相似文献
132.
133.
EMILIO SIENDONES YOLANDA JIMÉNEZ-GÓMEZ JOSÉ LUÍS MONTERO CONSUELO GÓMEZ-DÍAZ JOSÉ MANUEL VILLALBA JORDI MUNTANÉ 《Journal of gastroenterology and hepatology》2006,20(1):108-116
Background and Aim: PGE1 reduces in vivo and in vitro D-galactosamine (D-GalN)-induced cell death in hepatocytes. The present study was undertaken to elucidate the intracellular pathway by which D-GalN induces cell death in cultured hepatocytes. In addition, we evaluated if PGE1 was able to modulate different parameters related to D-GalN-induced apoptosis in cultured rat hepatocytes.
Methods: Hepatocytes were isolated from male Wistar rats (225–275 g) by the classical collagenase procedure. PGE1 (1 µM) was administered 2 h before D-GalN (5 mM) in primary culture of rat hepatocytes. Apoptosis was determined by DNA fragmentation and caspase-3, -6, -8 and -9 activation in hepatocytes. Caspase activation was evaluated by the detection of the related cleaved product and its associated activity. Cell necrosis was determined by the measurement of lactate dehydrogenase (LDH) activity in culture medium. To elucidate the role of mitochondria, we measured neutral (nSMase) and acid (aSMase) sphingomyelinase, as well as the expression of cytochrome c in mitochondria and cytoplasm fractions from D-GalN treated hepatocytes.
Results: D-GalN induced caspase-3 activation and DNA fragmentation in hepatocytes. This apoptotic response was not associated with the activation of caspase-6, -8 or -9. The use of specific inhibitors confirmed that only caspase-3 was involved in D-GalN-induced apoptosis. D-GalN did not modify nSMase and aSMase activities, nor mitochondrial cytochrome c release in hepatocytes.
Conclusions: D-GalN induced apoptosis through caspase-3 activation but without modification of the activity of caspase-6, -8, -9, SMases or cytochrome c release. PGE1 appears to prevent D-GalN-induced apoptosis by a mitochondria-independent mechanism. 相似文献
Methods: Hepatocytes were isolated from male Wistar rats (225–275 g) by the classical collagenase procedure. PGE
Results: D-GalN induced caspase-3 activation and DNA fragmentation in hepatocytes. This apoptotic response was not associated with the activation of caspase-6, -8 or -9. The use of specific inhibitors confirmed that only caspase-3 was involved in D-GalN-induced apoptosis. D-GalN did not modify nSMase and aSMase activities, nor mitochondrial cytochrome c release in hepatocytes.
Conclusions: D-GalN induced apoptosis through caspase-3 activation but without modification of the activity of caspase-6, -8, -9, SMases or cytochrome c release. PGE
134.
Peter MA Calverley Romain A Pauwels Paul W Jones Julie A Anderson J?rgen Vestbo 《INT J CHRONIC OBSTR》2006,1(3):209-218
Guidelines recommend that patients with COPD are stratified arbitrarily by baseline severity (FEV1) to decide when to initiate combination treatment with a long-acting β2-agonist and an inhaled corticosteroid. Assessment of baseline FEV1 as a continuous variable may provide a more reliable prediction of treatment effects. Patients from a 1-year, parallel-group, randomized controlled trial comparing 50 μg salmeterol (Sal), 500 μg fluticasone propionate (FP), the combination (Sal/FP) and placebo, (bid), were categorized post hoc into FEV1 <50% and FEV1 ≥50% predicted subgroups (n=949/513 respectively). Treatment effects on clinical outcomes – lung function, exacerbations, health status, diary card symptoms, and adverse events – were investigated. Treatment responses based on a pre-specified analysis explored treatment differences by severity as a continuous variable. Lung function improved with active treatment irrespective of FEV1; Sal/FP had greatest effect. This improvement appeared additive in milder disease; synergistic in severe disease. Active therapy significantly reduced exacerbation rate in patients with FEV1 <50% predicted, not in milder disease. Health status and breathlessness improved with Sal/FP irrespective of baseline FEV1; adverse events were similar across subgroups. The spirometric response to Sal/FP varied with baseline FEV1, and clinical benefits were not restricted to patients with severe disease. These data have implications for COPD management decisions, suggesting that arbitrary stratifications of baseline severity are not necessarily indicative of treatment efficacy and that the benefits of assessing baseline severity as a continuous variable should be assessed in future trials. 相似文献
135.
Mivazerol is a new and selective α2-adrenoceptor agonist which has demonstrated anti-ischemic effects, both in animals and in patients with myocardial ischemia. In the present study, mivazerol was evaluated for its ability to inhibit the release of catecholamines and serotonin (5-HT) in the hippocampus of freely moving rats, and also was compared to clonidine. In vivo microdialysis in combination with high-performance liquid chromatography (HPLC) was employed. Intravenous administration of mivazerol (8.0 μg/kg) had no effect on basal outflow of norepinephrine (NE), dopamine (DA) and 3,4-dihydroxyphenylacetic acid (DOPAC). In contrast, clonidine (8.5 μg/kg, i.v.) attenuated the basal release of DOPAC, which has been proposed to reflect NE biosynthesis, suggesting that clonidine has an inhibitory effect on NE synthesis. In addition, both mivazerol and clonidine decreased the spontaneous release of 5-HT, which provided further evidence that α2-adrenoceptors in the hippocampus modulate 5-HT. Sixty-min immobilization stress significantly increased the release of NE (177 ± 28%), DA (209 ± 46%) and DOPAC (337 ± 72%). Mivazerol (2.5, 8.0 and 25 μg/kg, i.v.) completely prevented the immobilization stress-induced enhancement of NE, DA and DOPAC, which was equi-effective to clonidine at a dose of 8.5 gmg/kg, i.v. These findings demonstrate that mivazerol has a profound modulatory effect on stress-induced neurotransmitter release in the hippocampus, at dose levels reported to protect against myocardial ischemia. 相似文献
136.
In order to investigate the validity of the hypothesis that acid-soluble peptides (ASP) in urinary excreta can be applied as an index of the protein catabolism of the whole body, we measured the urinary excretion of ASP in 46 normal children and in 18 children with Duchenne muscular dystrophy (DMD), in which continuous breakdown of skeletal muscle protein is presumed. The mean value of ASP in the children with DMD was significantly higher than that in normal controls. The concentration of ASP was correlated with that of 3-methylhistidine (3MH), which has been proposed as an index of muscle breakdown. This finding indicates that urinary ASP reflects the catabolism of body proteins. No correlation was observed between the concentration of ASP and that of 1-methylhistidine (1MH), which is used as an objective index of meat and fish ingestion. After the administration of bestatin, an inhibitor of leucine aminopeptidase, for 9 months, the urinary ASP concentration of children with DMD increased markedly. This increase is thought to have been directly caused by the bestatin itself. Urinary ASP is therefore apparently a more conveniently applied index of protein catabolism than is urinary 3MH, which requires the application of several restrictions. However, it should not be applied when the effect of bestatin administration is evident. 相似文献
137.
A Batak Indonesian from North Sumatra with hemoglobin (Hb) D Punjab (alpha 2 beta 2 121----Gln) and hemoglobin Constant Spring (Hb CoSp) is described. The 24-year-old man did not have clinical symptoms, and his hematological indices were normal. However, he had a persistent slight elevation of fetal hemoglobin level. His mother and his brother were heterozygous for Hb D Punjab; his father had Hb CoSp trait. A sister did not have any abnormal hemoglobin. To show the exact molecular defect leading to the synthesis of Hb CoSp in this family, genomic DNA from the father was analyzed by hybridization with synthetic oligonucleotides. Genomic DNA was digested with Sst I and Hind III producing a 1.05-kb fragment from the 3' end segment of the alpha 2-globin gene, including the termination codon. Two nonadecamers were synthesized to serve as probes: one, entirely homologous to the normal 3' end of alpha 2A-globin gene sequence, including the termination codon TAA, the other different from it by a replacement of the T in the termination codon TAA with C, changing it to CAA, the codon for the amino acid glutamine. DNA from normal controls gave a positive signal with the normal alpha 2TAA oligonucleotide probe but negative with the alpha 2 CAA probe. The father of propositus who had Hb CoSp trait gave a positive signal with the normal alpha 2TAA oligonucleotide probe as well as with the alpha 2CAA oligonucleotide probe, showing him to be heterozygous for the alpha 2CAA-globin gene. This result shows that the Hb CoSp in the Batak family is indeed due to a replacement of T by C in the TAA termination codon of the alpha 2-globin gene changing it to CAA the condon for glutamine. This explains the resulting readthrough of the untranslated sequence of the mRNA. 相似文献
138.
Detection of Epstein Barr virus in an hepatic leiomyomatous neoplasm in an adult human immunodeficiency virus 1-infected patient 总被引:5,自引:0,他引:5
S. Prévot J. Néris P. P. de Saint Maur 《Virchows Archiv : an international journal of pathology》1994,425(3):321-325
We report the first case of a human immunodeficiency virus (HIV)-related primary hepatic leiomyoma in an adult patient. The diagnosis was made at autopsy and confirmed by immunohistochemistry. Epstein Barr virus (EBV) was identified in tumour cells by in situ hybridization. Review of the literature revealed 13 cases of visceral myogenic tumours occuring in acquired immunodeficiency syndrome children, and only 2 cases in adults. One was a spinal epidural leiomyoma, the other multiple smooth muscle tumours of the colon and adrenal gland. This is the first report of EBV in smooth muscle neoplastic cells in an HIV-infected adult patient. 相似文献
139.
用刺激C_(57)小鼠胸腺细胞增生后H-TdR参入量的多少来表示IL-1活性的方法,研究长跑锻炼对老年人血浆白细胞介素-1(IL-1)活性的影响。结果表明,长跑锻炼10年以上老年人安静时血浆IL-1活性在14.7~18.7KD、3.8~7.0KD、1.5~2.6KD呈现三个淋巴细胞增生峰,分別为对照组老年人的214%、179%和146%(以对照组为100%)。对这种改变的机制和生理意义进行了讨论。 相似文献
140.
Spath M. M.; Pavensradt H.; Fischer R.; Schlunck G.; Wanner C.; Schollmeyer P. 《Nephrology, dialysis, transplantation》1994,9(7):758-763
The effect of histamine on the phosphoinositide turnover andintracellular free calcium activity [Ca2+]i was examined inhuman glomerular epithelial cells in culture. Addition of histamineto glomerular epithelial cells resulted in formation of inositolphosphates in a time- and dose-dependent manner. A transientmaximum of inositol trisphosphate (InsP3) was observed within10 s. Stimulation of protein kinase C by short-term pretreatment(15 mm) of glom erular epithelial cells with phorbol 12-mynstate13-acetate caused a dose-dependent inhibition of the histamine-inducedinositol phosphate accumulation. The baseline of [Ca2+]i inthe cells was 115 ±2.7 nmol/l (n=103). Histamine (ED50:approx. 2x107mol/l) caused a rapid and transient increasein [Ca2+]i, as detected by fura-2 microfluorimetry studies.In a calcium-free extracellular solution the rapid increaseof [Ca2+]i was still present. The H1 receptor antagonist mepyramine(IC50: approx. 8 x 109 mol/l) inhibited the histamine(106 mol/l) response on [Ca2+]i Cimetidine, a potentH2 receptor antagonist, showed no effect. This data indicates that H1 receptor activation causes hydrolysisof phosphatidylinositol 4, 5-bisphosphate by phospholipase Cactivation, and consecutive mobil ization of intracellular calcium.Since histamine is a mediator of inflammation, antigen responseand cellular injury, these findings could be of importance forthe understanding of glomerular epithelial cell pathology. 相似文献