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排序方式: 共有1585条查询结果,搜索用时 15 毫秒
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Béla Nagy Zsolt Bene Zsolt Fejes Sonya L. Heltshe David Reid Nicola J. Ronan Yvonne McCarthy Daniel Smith Attila Nagy Elizabeth Joseloff György Balla János Kappelmayer Milan Macek Scott C. Bell Barry J. Plant Margarida D. Amaral István Balogh 《Journal of cystic fibrosis》2019,18(2):271-277
Background
We have recently shown that human epididymis protein 4 (HE4) levels correlate with the severity of cystic fibrosis (CF) lung disease. However, there are no data on how HE4 levels alter in patients receiving CFTR modulating therapy.Methods
In this retrospective clinical study, 3 independent CF patient cohorts (US-American: 29, Australian: 12 and Irish: 19 cases) were enrolled carrying at least one Class III CFTR CF-causing mutation (p.Gly551Asp) and being treated with CFTR potentiator ivacaftor. Plasma HE4 was measured by immunoassay before treatment (baseline) and 1–6?months after commencement of ivacaftor, and were correlated with FEV1 (% predicted), sweat chloride, C-reactive protein (CRP) and body mass index (BMI).Results
After 1?month of therapy, HE4 levels were significantly lower than at baseline and remained decreased up to 6?months. A significant inverse correlation between absolute and delta values of HE4 and FEV1 (r?=??0.5376; P?<?.001 and r?=??0.3285; P?<?.001), was retrospectively observed in pooled groups, including an independent association of HE4 with FEV1 by multiple regression analysis (β?=??0.57, P?=?.019). Substantial area under the receiver operating characteristic curve (ROC-AUC) value was determined for HE4 when 7% mean change of FEV1 (0.722 [95% CI 0.581–0.863]; P?=?.029) were used as classifier, especially in the first 2?months of treatment (0.806 [95% CI 0.665–0.947]; P?<?.001).Conclusions
This study shows that plasma HE4 levels inversely correlate with lung function improvement in CF patients receiving ivacaftor. Overall, this potential biomarker may be of value for routine clinical and laboratory follow-up of CFTR modulating therapy. 相似文献3.
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Kaster MP Rosa AO Rosso MM Goulart EC Santos AR Rodrigues AL 《Neuroscience letters》2004,355(1-2):21-24
This study investigated the effect of adenosine in the forced swimming test (FST) and the tail suspension test (TST) in mice, and the contribution of adenosine A1 and A2A receptors to adenosine's antidepressant-like effect. The immobility time in the FST was reduced by adenosine given either by i.p. (5-10 mg/kg) or i.c.v. (0.01-10 microg/site) route. Adenosine (1-10 mg/kg, i.p.) also produced an antidepressant-like effect in the TST. No treatment affected locomotion in an open-field. The anti-immobility effect of adenosine (10 mg/kg, i.p.) in the FST was prevented by i.p. pretreatment of mice with caffeine (3 mg/kg), DPCPX (2 mg/kg) and ZM241385 (1 mg/kg). CHA (0.05 mg/kg, i.p.) and DPMA (1-5 mg/kg, i.p.) also produced an antidepressant-like effect in the FST. This is the first report of an antidepressant-like effect of adenosine in mice, apparently mediated through an interaction with A1 and A2A receptors. 相似文献
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The interaction of angiotensin II (ANG II) and atrial natriuretic peptide (ANP) on intracellular pH (pHi) and calcium ([Ca2+]i) was investigated in T84 cells (a permanent cell line derived from human colon epithelium) using the fluorescent stains BCECF/AM and Fluo 4/AM, respectively. pHi recovery rate mediated by the Na+/H+ exchanger (NHE) was examined following an NH4Cl pulse. Under control conditions pHi recovered at 0.114±0.005 pH units/min (n=35). ANG II (10–12 or 10–9 M) increased this value, whilst ANG II (10–7 M) decreased it. These effects of ANG II were impaired by simultaneous addition of 1 M or 25 M HOE-694, indicating that the stimulatory and inhibitory effects of ANG II on pHi recovery are mediated in part via the NHE1 and NHE2 isoforms. ANG II increased [Ca2+]i concentration-dependently. ANP (10–6 M) or dimethyl-BAPTA/AM (50 M) blocked the effects of ANG II on [Ca2+]i and on the rate of pHi recovery. Thapsigargin (10–5 M) enhanced the effect of ANG II on [Ca2+]i and reversed its stimulatory effect on the rate of pHi recovery to an inhibitory one. External Ca2+-free solution did not affect the effects of ANG II on these parameters. These data suggest that the [Ca2+]i increase induced by ANG II is dependent on intracellular calcium stores. They are compatible with the demonstration of two sites on the C-terminal of the Na+/H+ exchanger, one stimulating Na+/H+ activity by increases of [Ca2+]i in the lower range (at 10–12 or 10–9 M ANG II) and the other inhibiting this activity at high [Ca2+]i levels (at 10–7 M ANG II). ANP or dimethyl-BAPTA/AM, by impairing the pathway mediating the increase in [Ca2+]i, block both the stimulatory and inhibitory effects of ANG II. 相似文献
6.
Distinct Leishmania braziliensis isolates induce different paces of chemokine expression patterns 总被引:1,自引:0,他引:1
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Teixeira MJ Fernandes JD Teixeira CR Andrade BB Pompeu ML Santana da Silva J Brodskyn CI Barral-Netto M Barral A 《Infection and immunity》2005,73(2):1191-1195
Inflammatory events during Leishmania braziliensis infection in mice were investigated. Large lesions were directly correlated with the inflammatory reaction but not with parasite burden. Different L. braziliensis strains induce different paces of chemokine expression patterns, leading to diverse cell recruitment and differential inflammatory responses. 相似文献
7.
In the present study, the concentration of TGF-beta1 secreted by adherent cells isolated from human peripheral blood mononuclear cells (PBMC) and either stimulated with PGL-1 or lipopolysaccharide (LPS) or left unstimulated was determined by ELISA. The cells were isolated from untreated patients with different clinical forms of leprosy and healthy individuals. The adherent cells exhibited spontaneous release of TGF-beta1 in all clinical forms of leprosy and in healthy individuals; however, lepromatous leprosy/borderline leprosy (LL/BL) patients presenting erythema nodosum leprosum (ENL) displayed significantly higher concentrations of TGF-beta1 than either the other patients studied or the controls. These high TGF-beta1 levels were consistently observed when LL/BL ENL cells were stimulated with phenolic glycolipid (PGL-1) or LPS, and even in the absence of a stimulus (P < 0.01). The most significant differences in TGF-beta1 levels were observed when comparing the results in the presence of PGL-1 from ENL with, in order of significance: tuberculoid leprosy (TT) patients (P < 0.001), LL/BL patients without ENL (P < 0.01), healthy individuals (P < 0.01) and borderline-borderline/borderline-tuberculoid (BB/BT) patients with reversal reaction (RR) (P < 0.01). The BB/BT patients produced equivalent levels of TGF-beta1 compared with LL/BL patients without ENL, for all types of stimuli (P > 0.05). In contrast, TT patients produced the lowest levels of TGF-beta1 among all the subjects studied (both patients and healthy controls), especially following PGL-1 stimulation (P < 0.001, and P < 0.05, respectively). In conjunction with our previous data regarding TGF-beta1 expression in dermal lesions, it appears that TGF-beta1 probably plays different roles in leprosy: (i) to mediate a suppressive action locally, associated with the presence of PGL-1, and (ii) to induce proinflammatory effects when secreted systemically by monocytes, thereby acting as a modulatory cytokine in the acute inflammatory reactions of ENL and associated with the Th2 immune response in multibacillary forms of leprosy. 相似文献
8.
Hexavalent chromium is an established carcinogenic agent, which is not directly reactive with DNA. Its genotoxicity involves a reduction step, producing reactive oxygen species and radicals, and also lower valence forms which form stable complexes with intracellular macromolecules. The trivalent form of chromium may directly react with the genetic material and has also been shown to generate oxidative damage in vitro. To further evaluate the importance of in vivo oxidative DNA damage in the toxicity of each valence form, we conducted a comparative study on hexavalent and trivalent chromium-exposed workers (manual metal arc stainless steel welders and leather tanning workers), focusing on the total oxidative status by quantifying the level of lipoperoxidation products in urine. Thiol antioxidants are important in response to oxidative stress, and therefore, the concentration of glutathione and cysteine in peripheral blood lymphocytes was also determined. Chromium exposure was evaluated by quantifying total chromium in plasma and urine. Both groups had a significant increase in lipid peroxidation products expressed as malondialdehyde (MDA) in urine (tanners 1.42 +/- 0.61 micromol/g creatinine, welders 1.67 +/- 1.13 micromol/g creatinine versus controls 0.81 +/- 0.26 micromol/g creatinine, P < 0.005 in both cases) but only welders had a significant decrease in glutathione concentration in lymphocytes. There was a positive correlation between chromium in plasma and urinary MDA in welders, but not in tanners. This work is part of a larger study of which major results have been published previously including cytogenetics and DNA-protein cross-links in workers exposed to the two different forms of chromium. These results are compared with the results of oxidative damage from this study. 相似文献
9.
Patricia Ruiz-Iglesias Abril Gorgori-Gonzlez Maln Massot-Cladera Margarida Castell Francisco J. Prez-Cano 《Nutrients》2021,13(4)
Flavonoids are attracting increasing attention due to their antioxidant, cardioprotective, and immunomodulatory properties. Nevertheless, little is known about their role in exercise performance in association with immune function. This systematic review firstly aimed to shed light on the ergogenic potential of flavonoids. A search strategy was run using SCOPUS database. The returned studies were screened by prespecified eligibility criteria, including intervention lasting at least one week and performance objectively quantified, among others. Fifty-one studies (54 articles) met the inclusion criteria, involving 1288 human subjects, either physically untrained or trained. Secondly, we aimed to associate these studies with the immune system status. Seventeen of the selected studies (18 articles) assessed changes in the immune system. The overall percentage of studies reporting an improved exercise performance following flavonoid supplementation was 37%, the proportion being 25% when considering quercetin, 28% for flavanol-enriched extracts, and 54% for anthocyanins-enriched extracts. From the studies reporting an enhanced performance, only two, using anthocyanin supplements, focused on the immune system and found certain anti-inflammatory effects of these flavonoids. These results suggest that flavonoids, especially anthocyanins, may exert beneficial effects for athletes’ performances, although further studies are encouraged to establish the optimal dosage and to clarify their impact on immune status. 相似文献
10.