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排序方式: 共有762条查询结果,搜索用时 31 毫秒
1.

Background

Resistin is an immunometabolic mediator that is elevated in several inflammatory disorders. A ligand for Toll-like receptor 4, resistin modulates the recruitment and activation of myeloid cells, notably neutrophils. Neutrophils are major drivers of cystic fibrosis (CF) lung disease, in part due to the release of human neutrophil elastase- and myeloperoxidase-rich primary granules, leading to tissue damage. Here we assessed the relationship of resistin to CF lung disease.

Methods

Resistin levels were measured in plasma and sputum from three retrospective CF cohorts spanning a wide range of disease. We also assessed the ability of neutrophils to secrete resistin upon activation in vitro. Finally, we constructed a multivariate model assessing the relationship between resistin levels and lung function.

Results

Plasma resistin levels were only marginally higher in CF than in healthy control subjects. By contrast, sputum resistin levels were very high in CF, reaching 50–100 fold higher levels than in plasma. Among CF patients, higher plasma resistin levels were associated with allergic bronchopulmonary aspergillosis, and higher sputum resistin levels were associated with CF-related diabetes. Mechanistically, in vitro release of neutrophil primary granules was concomitant with resistin secretion. Overall, sputum resistin levels were negatively correlated with CF lung function, independently of other variables (age, sex, and genotype).

Conclusions

Our data establish relationships between resistin levels in the plasma and sputum of CF patients that correlate with disease status, and identify resistin as a novel mechanistic link between neutrophilic inflammation and lung disease in CF.  相似文献   
2.
Pharmacokinetics of a new macrolide, roxithromycin, in infants and children   总被引:1,自引:0,他引:1  
The pharmacokinetics of roxithromycin was investigated after oral administration of 2.5 mg/kg doses given 12 hours apart during 6 days in infants and children. These 18 subjects suffering from a respiratory tract infection were divided into three age groups: group I less than 18 months, group II less than 5 years, group III less than 13 years. At day 6, the elimination plasma half-life had an average value (mean +/- SD) of 19.8 +/- 9.7 h (group I), 21.0 +/- 9.4 h (group II) and 20.8 +/- 6.9 h (group III), respectively. The maximum concentration of roxithromycin (Cmax) was attained between 1 and 2 hours after dosing with mean values of 10.1 +/- 3.0 mg/l (group I), 8.7 +/- 4.9 mg/l (group II), 8.8 +/- 7.0 mg/l (group III). All the calculated pharmacokinetic parameters did not significantly differ from one group to another. The kinetics of roxithromycin in infants and children seemed to be age independent and showed no accumulation after repeated doses. During 12 hours, the plasma concentrations were above MIC of microorganisms generally present in respiratory tract infections. Two daily doses of 2.5 mg/kg of roxithromycin 12 hours apart may be proposed in infants and children.  相似文献   
3.
Summary The pharmacokinetics of famotidine has been investigated in ascitic cirrhotic patients. 10 decompensated cirrhotic patients were studied (9 m, 1 f), who had normal renal function, and six healthy control subjects (4 m, 2 f), matched for age, sex and weight. Each subject received on two occasions, at least four days apart, a single oral (40 mg) or intravenous dose (20 mg) of famotidine, at 21.00 h in a randomised manner. Serial blood samples were collected and famotidine in plasma was determined by a HPLC/UV method. Plasma data were subjected to non compartmental pharmacokinetic analysis.There were no statistically significant differences in pharmacokinetic parameters between the two groups after either the intravenous or oral administration of famotidine.The findings suggest that the dose of famotidine may not require any adjustment in ascitic patients without renal failure.  相似文献   
4.
IntroductionLiver transplantation is the standard treatment for end-stage liver disease. Brazil holds the third highest number of liver transplants performed per year, but center maldistribution results in high discrepancies in accessing this treatment. In 2012, an interstate partnership successfully implemented a new liver transplantation program in the middle west of Brazil. Here, we report the results of the first 500 liver transplants performed in this new program and discuss the impacts of a new transplant center in regional transplantation dynamics.MethodsWe reviewed data from the first 500 consecutive deceased donor liver transplants performed in the new program during an 8-year period. We analyzed data on patients’ clinical and demographic profiles, postoperative outcomes, and graft and recipient survival rates. Univariate survival analysis was conducted using log-rank tests to compare the groups.ResultsAlmost half (48%) of the procured organs and 40% of the recipients transplanted in our center were from outside our state. Recipient 30-day mortality was 9%. Overall recipient survival at 1 year and 5 years was 85% and 80%, respectively. Mortality was significantly associated with higher Model for End-Stage Liver Disease (P < .001) but not with the presence of hepatocellular carcinoma (P = .795).DiscussionThe new transplantation program treated patients from different regions of Brazil and became the reference center in liver transplantation for the middle west region. Despite the recent implementation, our outcomes are comparable to experienced centers around the world. This model can inspire the creation of new transplantation programs aiming to democratize access to liver transplantation nationwide.  相似文献   
5.
BackgroundIndividuals with cystic fibrosis (CF) have difficulty maintaining optimal vitamin D status due to pancreatic insufficiency-induced malabsorption, inadequate sunlight exposure, and poor intake of vitamin D containing foods. Vitamin D deficiency may increase the risk of pulmonary exacerbations of CF. The objective of this study was to assess factors impacting vitamin D status in patients with CF recently hospitalized for a pulmonary exacerbation of CF.MethodsThis was a pre-planned analysis of vitamin D intake in patients enrolled in a multi-center, double-blind, randomized controlled study examining vitamin D therapy for pulmonary exacerbation of CF. Demographic information, responses from a habitual sun exposure questionnaire and food frequency questionnaire, and vitamin D supplement usage were queried and compared to serum 25-hydroxyvitamin D (25(OH)D) concentrations.ResultsA total of 48 subjects were included in this analysis. Subjects were taking approximately 1,200 IU of vitamin D daily. Reported vitamin D intake, age, race, employment, and education were not significantly associated with vitamin D status in this population. However, smoking status, sunlight exposure in the last 3 years, and skin type (in the bivariate model) were all significantly associated with vitamin D status (all p<0.05).ConclusionsSunlight exposure was the most predictive determinant of vitamin D status in patients with CF prior to pulmonary exacerbation. Subjects reported vitamin D intake below the recommended amounts. The role and mode of optimizing vitamin D status prior to a pulmonary exacerbation needs further investigation.  相似文献   
6.
The home prothrombin time/international normalized ratio (PT/INR) self-management could be convenient for patients, enhancing treatment compliance and improving the quality of the oral anticoagulation. However, patient self-management (PSM) of oral anticoagulation may not be feasible for up to half of the patients due to cognitive or educational issues. In the present study, we aimed to evaluate the feasibility of a PSM program in a public health medical center that provides care for low-income patients. We also aimed to determine the accuracy of individual point-of-care devices (CoaguChek XS®) during long-term of home manipulation. Patients’ time-in-therapeutic range (TTR) and perception of quality of life, were evaluated at scheduled study-visits to the center. Additionally, the accuracy of individual CoaguChek XS® was evaluated in comparison to the standard automated coagulometer at scheduled study-visits to the center. Twenty-five patients were included in the PSM program. The median TTR of patients was 75 % before inclusion, 72 % at 3 months, 75 % at 6 months and 100 % at 12 months after the beginning of self-management (P = 0.14).The median DASS scores were 64, 63, 61.5 and 71.5 before inclusion and at 3, 6 and 12 months, respectively (P = 0.09). One hundred paired INR values were obtained. Correlation between INR values delivered by individual CoaguChek XS® and the automated coagulometer was 94 % and the mean result bias was 0.07 INR units. The coefficient of correlation and the mean bias between methods was stable during 24 months of follow-up. The present study suggests that PSM is feasible for patients treated in the public health system and that the results delivered by CoaguChek XS® have long-term reliability.  相似文献   
7.
Low- and middle-income countries account for the majority of hypertension disease burden. However, little is known about the distribution of this illness within subpopulations of these countries, particularly among those who live in urban informal settlements. A cross-sectional hypertension survey was conducted in 2003 among 5649 adult residents of a slum settlement in the city of Salvador, Brazil. Hypertension was defined as either an elevated arterial systolic (≥140 mmHg) or diastolic (≥90 mmHg) blood pressure. Sex-specific multivariable models of systolic blood pressure were constructed to identify factors associated with elevated blood pressure. The prevalence of hypertension in the population 18 years and older was 21 % (1162/5649). Men had 1.2 times the risk of hypertension compared with women (95 % confidence intervals (CI), 1.05, 1.36). Increasing age and lack of any schooling, particularly for women, were also significantly associated with elevated blood pressure (p < 0.05). There was also a direct association between men who were black and an elevated blood pressure. Among those who were hypertensive, 65.5 % were aware of their condition, and only 36.3 % of those aware were actively using anti-hypertensive medications. Men were less likely to be aware of their diagnosis or to use medications (p < 0.01 for both) than women. The prevalence of hypertension in this slum community was lower than reported frequencies in the non-slum population of Brazil and Salvador, yet both disease awareness and treatment frequency were low. Further research on hypertension and other chronic non-communicable diseases in slum populations is urgently needed to guide prevention and treatment efforts in this growing population.  相似文献   
8.
Background  Cystic fibrosis (CF) patients have chronic pancreatic insufficiency leading to malabsorption of fat-soluble vitamins, including vitamin D which can contribute to poor skeletal health and respiratory function.
Objective  This study evaluated the prevalence of vitamin D insufficiency and its impact on bone and respiratory health in adults with CF.
Design and measurements  This was a retrospective study in which data were collected from medical records over a 2-year period. Data included patient demographics, lung function, biochemical data, bone mineral densities, X-rays and ascertainment of use of vitamin supplements. Data were collected from medical records at a single accredited CF Center. Serum 25-hydroxyvitamin D [25(OH)D] levels and bone mineral density studies were also collected.
Patients  A total of 185 adults with CF were identified with a mean age of 29 ± 9 years.
Results  The prevalence of vitamin D insufficiency [25(OH)D < 75 nmol/l] was 76%. Mean serum 25(OH)D concentrations were 58·8 ± 30 nmol/l. Use of specific vitamin D supplementation was protective against vitamin D insufficiency whereas use of multivitamins was not. There was a small, but significant, positive association between serum 25(OH)D and FEV1 per cent predicted after controlling for age, gender, BMI and race ( R 2 = 0·30, P  < 0·001). A high prevalence (27%) of vertebral fractures was detected on lateral chest X-ray.
Conclusions  The prevalence of vitamin D insufficiency and poor skeletal health is high in the US CF population. Vitamin D status appears to be positively associated with lung function. Prospective studies to examine the impact of correction of vitamin D insufficiency on skeletal and lung health in adult CF are warranted.  相似文献   
9.
Gender affirming procedures adversely affect the reproductive potential of transgender people. Thus, fertility preservation options should be discussed with all transpeople before medical and surgical transition. In transwomen, semen cryopreservation is typically straightforward and widely available at fertility centers. The optimal number of vials frozen depends on their reproductive goals and treatment options, therefore a consultation with a fertility specialist is optimal. Experimental techniques including spermatogonium stem cells (SSC) and testicular tissue preservation are technologies currently under development in prepubertal individuals but are not yet clinically available. In transmen, embryo and/or oocyte cryopreservation is currently the best option for fertility preservation. Embryo cryopreservation requires fertilization of the transman’s oocytes with a donor or partner’s sperm prior to cryopreservation, but this limits his future options for fertilizing the eggs with another partner or donor. Oocyte cryopreservation offers transmen the opportunity to preserve their fertility without committing to a male partner or sperm donor at the time of cryopreservation. Both techniques however require at least a two-week treatment course, egg retrieval under sedation and considerable cost. Ovarian tissue cryopreservation is a promising experimental method that may be performed at the same time as gender affirming surgery but is offered in only a limited amount of centers worldwide. In select places, this method may be considered for prepubertal children, adolescents, and adults when ovarian stimulation is not possible. Novel methods such as in-vitro activation of primordial follicles, in vitro maturation of immature oocytes and artificial gametes are under development and may hold promise for the future.  相似文献   
10.
This work aimed at determining the ideal ischemia time in an in vitro ischemia-reperfusion model of spinal cord injury. Rat spinal cord slices were prepared and then exposed or not to oxygen deprivation and low glucose (ODLG) for 30, 45, 60, 75 and 90 minutes. Cell viability was assessed by triphenyltetrazolium (TTC), lactate dehydrogenase (LDH) release, and fluorochrome dyes specific for cell dead (ethidium homodimer) using the apotome system. Glutamate release was enzymatically measured by a fluorescent method. Gene expression of apoptotic factors was assessed by real time RT-PCR. Whereas spinal cord slices exposed to ODLG exhibited mild increase in fluorescence for 30 minutes after the insult, the 45, 60, 75 and 90 minutes caused a 2-fold increase. ODLG exposure for 45, 60, 75 or 90 minutes, glutamate and LDH release were significantly elevated. nNOS mRNA expression was overexpressed for 45 minutes and moderately increased for 60 minutes in ODLG groups. Bax/bcl-xl ratio, caspase 9 and caspase 3 mRNA expressions were significantly increased for 45 minutes of ODLG, but not for 30, 60, 75 and 90 minutes. Results showed that cell viability reduction in the spinal cord was dependent on ischemic time, resulting in glutamate and LDH release. ODLG for 45 minutes was adequate for gene expression evaluation of proteins and proteases involved in apoptosis pathways.  相似文献   
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