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31.
AIMS: Although the majority of patients with overactive bladder (OAB) are continent, most patient-reported outcome measures for OAB were designed for patients with urinary incontinence. The overactive bladder questionnaire (OAB-q) was developed to assess symptom bother and HRQL among both continent and incontinent OAB patients; however, the responsiveness of the OAB-q among continent patients has not been evaluated. The purpose of this analysis was to assess the responsiveness of the OAB-q among OAB patient subgroups with a focus on continent patients. METHODS: Post-hoc analyses were conducted from two 12-week trials of tolterodine for the treatment of OAB. Patients completed the OAB-q and daily bladder diaries (assessing frequency, urgency, and incontinence episodes) at baseline, 4 weeks, and 12 weeks. Three patient subgroups were identified on the basis of continence status at all three timepoints: (1) continent; (2) incontinent; and (3) incontinent at baseline and continent by Week 12 (ITC). General linear models were used to compare changes from baseline, and Spearman correlations assessed the association between OAB-q changes and bladder diary changes. Effect sizes were computed separately for each group. RESULTS: A total of 262 continent, 552 incontinent, and 397 ITC patients were included in this analysis. Continent patients tended to be younger than incontinent patients, and patients were predominantly female, although continent patients had the highest percentage of male patients in both studies. Compared with continent patients, patients who were incontinent at baseline tended to have greater symptom bother and lower HRQL at baseline. All OAB-q change scores were consistently greatest for the ITC group (12.1-33.9), and greater for continent patients (10.8-28.6) than for incontinent patients (7.6-20.1). All three groups of patients experienced reductions in frequency and urgency episodes, and these changes were significantly correlated with changes in the OAB-q scales. Among all three groups, effect sizes were in the moderate-to-large range for all OAB-q subscales except Social Interaction. CONCLUSIONS: The OAB-q is highly responsive to change between continent and incontinent patients with OAB, and is a valid tool for measuring treatment outcomes among continent OAB patients.  相似文献   
32.
Objective: To develop the techniques needed for the specific gene/protein targeting transfection experiments in isolated lymphatic vessels, we completed two major tasks: 1) optimize the experimental conditions to maintain the viability of isolated rat lymphatic vessels in culture for sufficiently long periods of time to permit knockdown or overexpression of selected proteins/genes and 2) develop effective transfection protocols for lymphatic muscle and endothelial cells in intact lymphatic vessels without nonspecific impairment of lymphatic contractile function due to the transfection protocol itself. Methods: Experimental protocols were developed for the maintenance of isolated lymphatic vessels under nonpressurized and pressurized conditions for 3–12 days in culture and for adenoviral gene transfection of the lymphatic muscle and endothelial cells. Results: The data demonstrate the effectiveness of the newly developed experimental protocols for the maintenance of isolated rat mesenteric lymphatic vessels and thoracic duct in culture up to 3–12 days without significant impairment of the parameters of their pumping and effective adenoviral/GFP transfection of lymphatic endothelial and muscle cells in isolated rat mesenteric lymphatic vessels. Conclusions : These experimental techniques will extend the set of the modern experimental tools available to researchers investigating the physiology of lymphatic function.  相似文献   
33.
Aquatic organisms are exposed to a variety of natural chemical stressors such as humic substances. The aim of this study was to investigate the mode of action of natural organic matter (NOM, roughly 80% of which is humic substances) on two freshwater amphipods from Lake Baikal, Eulimnogammarus verrucosus (Gerstf.) and Eulimnogammarus cyaneus (Dyb.), in order to assess the potential oxidative stress of NOM impact. Chosen as oxidative stress markers were lipid peroxidation and cell internal hydrogen peroxide level as well as peroxidase, catalase, and glutathione S-transferase activities. Exposure of amphipods to NOM caused a significant increase in lipid peroxidation but a concomitant decrease in hydrogen peroxide concentration, and peroxidase and (to a lesser degree) glutathione S-transferase activities. An interim increase of catalase activity was observed. A possible reason for the decrease in major antioxidant enzyme activity is exhaustion of the reservoir of reduced substrates in the first stage of the antioxidant defense reaction. Despite the inhibition of major antioxidant enzymes, the studied amphipods were able to successfully resist the NOM oxidative impact and, at low NOM concentrations, to combat lipid peroxidation processes.  相似文献   
34.
Peptide nucleic acid conjugates: synthesis, properties and applications   总被引:2,自引:0,他引:2  
Artificial control of gene expression has great potential in the treatment of many human diseases, and peptide nucleic acids (PNAs) offer several potential advantages for silencing gene expression in mammalian cells. The pseudopeptide backbone of the PNA makes it resistant to enzymatic degradation, and PNAs bind complementary DNA and RNA with high affinity and specificity. PNAs are potentially leading agents for antigene and antisense therapeutics, but the application of PNAs in the in vivo setting is hampered by their poor intracellular delivery. This problem has been addressed by PNA conjugation to lipophilic moieties, peptides, and cell-specific receptor ligands. The biological activity of PNAs can also benefit from conjugation to DNA interactive compounds like intercalators and alkylators. Here we review the most interesting literature concerning PNA conjugation with small molecules, emphasizing synthetic approaches, properties and applications of the PNA conjugates.  相似文献   
35.
BACKGROUND: After the double-blind, placebo-controlled Systolic Hypertension in Europe (Syst-Eur) trial ended in February 1997, randomized patients were offered active study medication for a further period of observation. OBJECTIVE: To refine the estimates of the long-term effects of antihypertensive therapy on the incidence of dementia. METHODS: Eligible patients had no dementia and were at least 60 years old. Their systolic blood pressure at entry was 160 to 219 mm Hg, with diastolic blood pressure below 95 mm Hg. Antihypertensive therapy was started immediately after randomization in the active treatment group, but only after termination of the double-blind trial in the control patients. Treatment consisted of nitrendipine (10-40 mg/d), with the possible addition of enalapril maleate (5-20 mg/d), hydrochlorothiazide (12.5-25 mg/d), or both add-on drugs. RESULTS: Median follow-up increased from 2.0 years in the double-blind trial to 3.9 years overall. The incidence of dementia doubled from 32 to 64 cases, 41 of whom had Alzheimer disease. Throughout follow-up, systolic/diastolic blood pressure was 7.0/3.2 mm Hg higher in the 1417 control patients than in the 1485 subjects randomized to active treatment. At the last examination, the blood pressure difference was still 4.2/2.9 mm Hg; 48.1%, 26.4%, and 11.4% of the control patients were taking nitrendipine, enalapril, and/or hydrochlorothiazide, whereas in the active treatment group these proportions were 70.2%, 35.4%, and 18.4%, respectively. Compared with the controls, long-term antihypertensive therapy reduced the risk of dementia by 55%, from 7.4 to 3.3 cases per 1000 patient-years (43 vs 21 cases, P<.001). After adjustment for sex, age, education, and entry blood pressure, the relative hazard rate associated with the use of nitrendipine was 0.38 (95% confidence interval, 0.23-0.64; P<.001). Treatment of 1000 patients for 5 years can prevent 20 cases of dementia (95% confidence interval, 7-33). CONCLUSION: The extended follow-up of Syst-Eur patients reinforces the evidence that blood pressure-lowering therapy initiated with a long-acting dihydropyridine protects against dementia in older patients with systolic hypertension.  相似文献   
36.
Julien MD  Polonskaya Z  Hearing J 《Virology》2004,326(2):317-328
Initiation of DNA replication from within the Epstein-Barr virus (EBV) latent cycle origin oriP occurs once per cell cycle and is almost entirely dependent upon cellular proteins. The human origin recognition complex (ORC) is recruited to oriP and orchestrates the events that lead to the initiation of replication. EBNA-1, the sole viral protein required for oriP-plasmid replication, binds four sites within the replicator but the role(s) it plays in the replication of oriP plasmids has not been elucidated. We investigated the recruitment of ORC to oriP in vivo and show that the binding of EBNA-1 to the replicator is necessary for the association of the ORC subunit Orc2 with the replicator. The minimal replicator of oriP consists of two EBNA-1 binding sites flanked by perfect 14-bp inverted repeats (a and b), but these repeats are dispensable for the association of Orc2 with the replicator. A mutational analysis of the 14-bp repeats provided additional support for a role for the telomere repeat binding protein 2 in oriP replicator function. We show that nucleotide differences between the oriP replicator of the B95-8 and Raji EBV genomes are not solely responsible for the inefficient utilization of this origin in the Raji EBV genome.  相似文献   
37.
38.
Cr(VI) is a human and animal carcinogen. Cr(VI) does not interact directly with DNA and thus its genotoxicity is attributed to its intracellular reduction to Cr(III) via reactive intermediates. The resulting types of DNA damage can be grouped into two categories: (1) oxidative DNA damage and (2) Cr(III)-DNA interactions. This study examines the molecular mechanism of Cr(VI) and Cr(III) genotoxicity in an intact cell. A system screening for DNA deletions (DEL assay) was used to compare induction of chromosomal rearrangements in the yeast Saccharomyces cerevisiae following Cr(VI) and Cr(III) exposure. Both forms of chromium induced DNA deletions albeit with different dose-response curves. N-acetylcysteine had a protective effect against Cr(VI) genotoxicity at high exposure doses but had no protective effect at lower doses or against Cr(III). An oxidative DNA damage repair mutant was hypersensitive to Cr(VI) only at high exposure and the mutant was not hypersensitive to Cr(III) exposure. These data imply that oxidative stress is involved in Cr(VI) genotoxicity at high exposure concentrations and not so in Cr(III). The Cr(III)-DNA interaction appears to be an important genotoxic lesion following Cr(VI) exposure at low-exposure concentrations. The CAN forward mutation assay revealed that within the concentration ranges used for this study, Cr(III) does not cause point mutations and Cr(VI) causes a mild but statistically significant increase in point mutation only at the highest concentration tested. This study reveals that DNA deletions occurring as a result of intrachromosomal homologous recombination are a useful endpoint for studying chromium genotoxicity.  相似文献   
39.

Objective

The significance of liver stiffness (LS) in the setting of cardiovascular congestion during the course of acute decompensated heart failure (ADHF) is under investigation. The aim of this study was to assess LS with the use of transient elastography (TE) and its associations with volume overload as determined by means of bioimpedance vector analysis (BIVA) in ADHF.

Methods and Results

TE (Fibroscan 502; Echosens) and BIVA (ABC-01, Medass) were performed in the first 48 hours of admission and on the day of discharge in 149 ADHF patients without known primary chronic liver disease or acute hepatitis. During hospitalization the median value of LS decreased from 12.2 kPa (interquartile range 6.3–23.6) to 8.7 (5.9–14.4) kPa (P < .001). Changes in LS correlated (P < .001) with changes in weight and BIVA parameters. LS was compared with histologic features of livers of ADHF patients who died (n?=?7). Liver fibrosis 2B-4 was observed but was not associated with LS. LS at discharge was associated with increased risk of 12-month all-cause death, HF readmission, and the combined end point.

Conclusions

There was a moderate association between LS with clinical congestion and volume overload according to BIVA and no correlation with degree of histologic liver fibrosis. LS may be a marker of negative HF outcomes.  相似文献   
40.
AIMS: Ularitide is a synthetic form of urodilatin, a natriuretic peptide produced in the kidney with vasodilating, natriuretic, and diuretic effects, that offers promise for the management of decompensated heart failure (DHF). We assessed the efficacy and safety of ularitide in treating patients with DHF. METHODS AND RESULTS: In this Phase II randomized, double-blind, placebo-controlled trial, 221 DHF patients received either placebo (n=53) or ularitide at 7.5 ng/kg/min (n=60), 15 ng/kg/min (n=53), or 30 ng/kg/min (n=55) as a 24-h continuous infusion. At 6 h, ularitide demonstrated a significant decrease in pulmonary capillary wedge pressure (P=0.052, P=0.000004, P=0.000002, respectively) and improved dyspnoea score in the 7.5, 15, and 30 ng/kg/min ularitide group (P=0.0026, P=0.0026, P=0.0013, respectively). Ularitide reduced systemic vascular resistance and increased cardiac index for the 15 and 30 ng/kg/min groups (P=0.017, P=0.00002, respectively). Systolic blood pressure (BP) decreased dose dependency. Heart rate and serum creatinine were unchanged through day 3. Most frequently reported drug-related adverse events through day 3 in all ularitide groups were dose-dependent BP decrease and hypotension. CONCLUSION: Ularitide lowered cardiac filling pressures and improved dyspnoea without apparent early deleterious effects on renal function in DHF patients. These results suggest that ularitide may play a role in the management of DHF.  相似文献   
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