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91.
Objectives:The aim of this study was to assess the therapeutic effectiveness of adefovir dipivoxil (ADV), administered in combination with lamivudine (LAM) or as monotherapy, and the rate of resistance to ADV, in hepatitis B e antigen (HBeAg)-negative adult patients with chronic hepatitis B virus (HBV) infection and clinical or virologic resistance to LAM. Furthermore, we evaluated in these selected patients the clinical co-variates associated with a sustained virologic response. Methods:Data from adult outpatients aged >18 years with chronic HBV infection and clinical or virologic resistance to LAM were used in this retrospective, multicenter, nonrandomized, open-label study. Patients were selected if they received ADV 10 mg PO QD + LAM 100 mg QD PO or ADV 10 mg PO QD as monotherapy for 24 to 32 months between June 2003 and July 2006. End points were the proportions of patients who achieved virologic response (undetectable HBV-DNA [<3.3 log(10) copies/mL]) and biochemical response (normalization [<40 IU/L] of alanine aminotransferase [ALT]), and the proportions in whom resistance to ADV (rebound serum HBV-DNA >1 log(10) copies/mL compared with on-treatment nadir, as confirmed on molecular analysis) was found. HBV-DNA and ALT levels were checked every month during the first 3 months of treatment and every 3 months thereafter until 28 months. Data from each center were stored in a centralized database and analyzed by a blinded independent investigator. Results:Data from 70 patients were included (48 men, 22 women; median age, 51 years; ADV + LAM, 36 patients; ADV monotherapy, 34). The median duration of the pharmacologic treatment in the 2 groups of patients was 28 months (range, 24-32 months). By month 3, virologic response was achieved in 30 patients (83%) in the ADV + LAM group and in 26 patients (76%) in the ADV monotherapy group. At 12 months, virologic response was achieved in 5 additional patients in the ADV + LAM group and 2 additional patients in the ADV monotherapy group. Biochemical response was found to be time dependent: in the 2 groups, the rates of biochemical response were, respectively, 56% and 54% at month 3, 80% and 71% at month 6, and 96% and 79% at month 12, persisting up to the end of the study period. The rates of clinical resistance to ADV were 3% with ADV + LAM and 18% with ADV monotherapy (with a 6% rate of resistance due to rtA181 mutation in the monotherapy group). Logistic regression analysis found that pre-treatment levels of HBV-DNA <5 log(10) copies/mL, ALT levels >150 IU/L, an inflammation score >7, and a fibrosis score <2 were the strongest covariates independently associated with a sustained virologic response in both groups of patients. No adverse events were reported in any of the patients. Conclusion:ADV, administered in combination with LAM or as monotherapy, appeared to be effective in this small, selected group of HBeAg-negative patients with clinical or virologic resistance to LAM, especially in those with low pretreatment HBV-DNA levels, high ALT levels, and low fibrosis scores.  相似文献   
92.
It has been reported that the endocannabinoid anandamide (AEA) exerts an adverse effect on human sperm motility, which has been ascribed to inhibition of mitochondrial activity. This seems to be at variance with evidence suggesting a major role of glycolysis in supplying ATP for sperm motility; furthermore, the role of AEA-binding receptors in mediating mitochondrial inhibition has not yet been explored. In this study, human sperm exposure to Met-AEA (methanandamide, nonhydrolyzable analog of AEA) in the micromolar range significantly decreased mitochondrial transmembrane potential (ΔΨm), similarly to rotenone, mitochondrial complex I inhibitor. The effect of Met-AEA (1 μm) was prevented by SR141716, CB(1) cannabinoid receptor antagonist, but not by SR144528, CB(2) antagonist, nor by iodoresiniferatoxin, vanilloid receptor antagonist. The effect of Met-AEA did not involve activation of caspase-9 or caspase-3 and was reverted by washing. In the presence of glucose, sperm exposure either to Met-AEA up to 1 μm or to rotenone for up to 18 h did not affect sperm motility. At higher doses Met-AEA produced a CB(1)-independent poisoning of spermatozoa, reducing their viability. Under glycolysis blockage, 1 μm Met-AEA, similarly to rotenone, dramatically abolished sperm motility, an effect that was prevented by SR1 and reverted by washing. In conclusion, CB(1) activation induced a nonapoptotic decrease of ΔΨm, the detrimental reflection on sperm motility of which could be revealed only under glycolysis blockage, unless very high doses of Met-AEA, producing CB(1)-independent sperm toxicity, were used. The effects of CB(1) activation reported here contribute to elucidate the relationship between energetic metabolism and human sperm motility.  相似文献   
93.
Long-term non-progressors (LTNP) are human immunodeficiency virus (HIV)-infected individuals characterized by the absence of disease, low viral loads and stable or even increasing CD4(+) T cell counts for prolonged periods of time. In these subjects, an HIV-specific immune response which is either stronger or directed against a wider array of viral epitopes than that seen in progressors, can be often detected. Here, we summarize the characteristics of HIV-specific CD4(+) and CD8(+) T cell responses in LTNP, and discuss how a highly effective T cell-mediated immune response against HIV might contribute to the establishment of this particular condition.  相似文献   
94.

Purpose  

To assess the feasibility of remifentanil-based sedation in hypoxemic acute respiratory failure (HARF) patients refusing to continue noninvasive ventilation (NPPV) for intolerance to two different interfaces—helmet and total face mask.  相似文献   
95.
96.
BACKGROUND: Elevated plasma levels of endothelin-1 (ET-1) have been reported in advanced atherosclerosis. Further in vivo demonstration of cause-effect relationship between atherosclerotic lesion and high levels of ET-1 needs to be carried out. The aim of this study was to determine whether circulating levels of ET-1 are influenced by removing haemodynamically significant atherosclerotic stenosis in selected patients with mono or bilateral carotid atherosclerotic stenosis. METHODS: Cubital venous ET-1-immunoreactive (IR) levels were measured in 20 patients: 11 (mean age+/-S.D. 63.1+/-5.36 years; range 53-70 years) were affected by monolateral, and nine patients (mean age+/-S.D. 64.7+/-9.8 years; range 52-78 years) by bilateral extracranial carotid artery atherosclerotic stenosis. ET-1-IR levels were evaluated before and 7 days after monolateral surgical endoarterectomy. Pre-surgery levels of ET-1-IR were compared with those obtained from 18 healthy younger volunteers (mean age+/-S.D. 27.8+/-2.7 years; range 20-50 years). FINDINGS: The mean cubital venous levels of ET-1-IR in the atherosclerotic patients before endoarterectomy (mean+/-S.D. 4.50+/-3.35 pg/ml; range 1.28-10.66 pg/ml) were significantly higher than those observed in healthy subjects (mean+/-S.D. 0.641+/-0.137 pg/ml; range 0.36-1.02 pg/ml) (P=0.000). The mean ET-1-IR level decreased significantly after endoarterectomy in the group of patients with monolateral stenosis (pre-surgery: mean+/-S.D. 4.35+/-3.11 pg/ml; range 1.28-10.66 pg/ml; post-surgery: mean+/-S.D. 3.05+/-2.94 pg/ml, range 0.28-8.86 pg/ml) (P=0.005), but not in patients with bilateral extracranial carotid stenosis submitted to monolateral endoarterectomy (pre-surgery: mean+/-S.D. 4.77+/-3.79 pg/ml; range 2.18-10.3 pg/ml; post-surgery: mean+/-S.D. 4.60+/-3.70 pg/ml; range 2.20-11.10 pg/ml). INTERPRETATION: The removal of a haemodynamically significant atherosclerotic vascular stenosis is associated with a decrease in the circulating ET-1-IR levels 7 days after surgery when haemodynamically significant atherosclerotic lesions are absent.  相似文献   
97.
BackgroundOnly few studies have assessed sexual dysfunction in men with Klinefelter syndrome (KS).AimTo define pooled prevalence estimates and correlates of erectile dysfunction (ED) and decreased libido (DL) in KS.MethodsA thorough search of Medline, Embase and Web of Science was performed to identify suitable studies. Quality of the articles was scored using the Assessment Tool for Prevalence Studies. Data were combined using random effect models and the between-studies heterogeneity was assessed by the Cochrane's Q and I2. The sources of heterogeneity were investigated by meta-regression and sub-group analyses. Funnel plot, Begg's rank correlation and trim-and-fill test were used to assess publication bias.Main Outcome MeasureThe pooled prevalence of ED and DL in KS as well as 95% confidence intervals (CIs) were estimated from the proportion of cases of sexual dysfunction and the sample size. Variables that could affect the estimates were identified by linear meta-regression models.ResultsSixteen studies included collectively gave information about ED and DL in 482 and 368 KS men, respectively, resulting in a pooled prevalence of 28% (95% CI: 19%–36%) for ED and 51% (95% CI: 36%–66%) for DL, with a large heterogeneity. The trim-and-fill adjustment for publication bias produced a negligible effect on the pooled estimates. At the meta-regression analyses, a higher prevalence of ED was significantly associated with an older age but not with lower testosterone levels. In series with a mean age >35 years, the ED prevalence estimate increased up to 38% (95% CI: 31%–44%) with no heterogeneity (I2=0.0%, P=0.6). On the contrary, the prevalence of DL increased significantly as testosterone levels decreased, without a significant relationship with age.Clinical ImplicationsWhile DL would largely reflect an androgen deficiency, in older men with KS, erectile function should be assessed irrespective of testosterone levels.Strength & LimitationsThis is the first meta-analysis defining pooled prevalence estimates and correlates of ED and DL in KS. Nevertheless, caution is required when interpreting results, due to the high risk of bias in many studies, as well as the dearth of data about psychosocial and/or psychosexological variables and age at the diagnosis.ConclusionsED and DL represent common clinical complaints in KS. While the prevalence of ED would increase with age, DL gets more common as serum testosterone decreases. Further studies are warranted to elucidate the pathogenetic mechanism(s) underlying the age-dependent increase in the prevalence of ED, apparently unrelated to the androgenic status.A Barbonetti, S D'Andrea, W Vena, et al. Erectile Dysfunction and Decreased Libido in Klinefelter Syndrome: A Prevalence Meta-Analysis and Meta-Regression Study. J Sex Med 2021;18:1054–1064.  相似文献   
98.
BACKGROUND: Predicting factors for the outcome of conventional Helicobacter pylori triple therapy have been identified. Of these, the presence of the CagA gene is a strong predictor of successful treatment. Our preliminary data show that this factor becomes irrelevant when sequential therapy is used. AIM: To identify predicting factors for the outcome of H. pylori eradication using two therapeutic schemes (triple and sequential) of equal duration (10 days). METHODS: Ninety-six patients with H. pylori infection were randomly assigned to receive one of the following therapeutic schemes: group A: rabeprazole (20 mg b.d.) plus amoxicillin (1 g b.d.) for 5 days, followed by rabeprazole (20 mg b.d.) plus tinidazole (500 mg b.d.) and clarithromycin (500 mg b.d.) for a further 5 days; group B: rabeprazole (20 mg b.d.) plus amoxicillin (1 g b.d.) and clarithromycin (500 mg b.d.) for 10 days. Age, sex, smoking, endoscopic and histological findings, and CagA and VacA status were considered as candidates for a model of multivariate analysis which used therapeutic outcome as the dependent variable. CagA and VacA status were assessed by polymerase chain reaction on DNA isolated from gastric antral specimens. RESULTS: The sequential scheme was significantly more effective than prolonged triple therapy (P < 0.05). Smoking (P < 0.001) and the absence of the CagA gene (P < 0.05) were significantly associated with the failure of triple therapy, but the effectiveness of sequential treatment was not predicted by these factors. CONCLUSION: Our data suggest that sequential therapy is not affected by bacterial and host factors which have, until now, predicted the outcome of conventional eradication treatments.  相似文献   
99.
In this study, the effect of human sperm exposure to progesterone on sperm/oocyte fusion, using the hamster egg penetration test, and on sperm/zona pellucida (ZP) binding, using the hemizona assay, was investigated under various experimental conditions. A brief exposure of human spermatozoa to progesterone exerted a stimulatory effect on sperm/oocyte fusion which was dose-dependent, capacitation-dependent, influenced by the source of serum albumin in capacitating medium, and was higher than that produced by the exposure to progesterone from the onset of capacitation. The exposure of capacitated spermatozoa to progesterone during 20 min-spermatozoa/ZP-coincubation produced an enhancement of ZP-binding, which was not significantly influenced by the source of serum albumin in capacitating medium. A significantly lower ZP-binding was exhibited by spermatozoa exposed to progesterone from the beginning of capacitation. These results indicate that progesterone exerts a stimulatory effect on human sperm's fertilizing ability, which occurs mainly in post-capacitation events directly involved in sperm/oocyte fusion and in ZP-binding. Conditions optimizing these effects are provided. They should be taken into account in the standardization of experimental and clinical studies designed to evaluate the response of human spermatozoa to progesterone.  相似文献   
100.

Aim:

To evaluate the efficacy of otilonium bromide, a spasmolytic agent, in the treatment of irritable bowel syndrome using modern and validated diagnostic criteria.

Methods:

Three hundred and seventy-eight patients with irritable bowel syndrome were enrolled in the study. At entry, endoscopy/barium enema, clinical examination and laboratory tests were used to rule out organic diseases. After a 2-week placebo run-in, 325 patients were randomly assigned to receive either otilonium bromide 40 mg t.d.s. or placebo for 15 weeks. Abdominal pain, abdominal distension and disturbed defecation were scored at the beginning of the study and every 5 weeks. A global determination of well-being by visual analogue scale and the tenderness of the sigmoid colon were also scored.

Results:

The reduction in the number of abdominal pain episodes was significantly higher (P < 0.01) in otilonium bromide patients (55.3%) than in those taking placebo (39.9%) as was the severity of abdominal distension (42.0% vs. 30.2%; P < 0.05). Bowel disturbance improved in both groups, but without any statistically significant difference. The visual analogue scale of well-being revealed a significant improvement (P < 0.05) in patients taking otilonium bromide. The investigators’ global positive assessment was in favour of otilonium bromide (65.2%) compared with placebo (49.6%) (P < 0.01).

Conclusions:

Otilonium bromide may represent an effective treatment for irritable bowel syndrome because it reduces its predominant symptom (abdominal pain/discomfort) more than placebo does.
  相似文献   
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