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1.
The main reason why peritoneal dialysis (PD) still has limited use in the management of patients with end-stage renal disease (ESRD) lies in the fact that the currently used glucose-based PD solutions are not completely biocompatible and determine, over time, the degeneration of the peritoneal membrane (PM) and consequent loss of ultrafiltration (UF). Here we evaluated the biocompatibility of a novel formulation of dialytic solutions, in which a substantial amount of glucose is replaced by two osmometabolic agents, xylitol and l-carnitine. The effect of this novel formulation on cell viability, the integrity of the mesothelial barrier and secretion of pro-inflammatory cytokines was evaluated on human mesothelial cells grown on cell culture inserts and exposed to the PD solution only at the apical side, mimicking the condition of a PD dwell. The results were compared to those obtained after exposure to a panel of dialytic solutions commonly used in clinical practice. We report here compelling evidence that this novel formulation shows better performance in terms of higher cell viability, better preservation of the integrity of the mesothelial layer and reduced release of pro-inflammatory cytokines. This new formulation could represent a step forward towards obtaining PD solutions with high biocompatibility.  相似文献   
2.
The endothelial glycocalyx, the gel layer covering the endothelium, is composed of glycosaminoglycans, proteoglycans, and adsorbed plasma proteins. This structure modulates vessels’ mechanotransduction, vascular permeability, and leukocyte adhesion. Thus, it regulates several physiological and pathological events. In the present review, we described the mechanisms that disturb glycocalyx stability such as reactive oxygen species, matrix metalloproteinases, and heparanase. We then focused our attention on the role of glycocalyx degradation in the induction of profibrotic events and on the possible pharmacological strategies to preserve this delicate structure.  相似文献   
3.
This study examined the feasibility of using cellular telephones to improve access to smoking cessation counseling in a low-income, HIV-positive population. Two pilot studies were conducted: (a). A survey of interest and barriers in participating in a smoking cessation intervention (n=49) and (b). a cellular telephone smoking cessation intervention in which participants were provided with free cellular telephones and received six telephone counseling sessions over a 2-week period (n=20). A primary care clinic serving a multiethnic, medically indigent, HIV-positive population served as the setting. Demographics and smoking status were assessed by self-report and expired-air carbon monoxide testing. In study 1, participants reported multiple barriers to participating in a smoking cessation intervention, including transportation, transience, and telephone availability. However, they also reported a high level of interest in participating in a smoking cessation intervention, with the greatest interest in a cellular telephone intervention. In study 2, 19 of the 20 participants successfully completed 2 weeks of smoking cessation counseling with a 93% (106 of 114 calls) contact rate. A total of 19 participants made a quit attempt, and the 2-week end of treatment point-prevalence abstinence rate was 75%. The provision of cellular telephones allowed for the implementation of a proactive telephone smoking cessation intervention providing an underserved population with access to care. Cellular telephones also may provide unique benefits because of the intensity of counseling and support provided as well as the ability to provide counseling in real-world, real-time situations (in vivo counseling).  相似文献   
4.
BACKGROUND: Malassezia species are lipophilic yeasts that are emerging as nosocomial pathogens, particularly in low-birth-weight neonates who receive lipid emulsions. When a cluster of patients with Malassezia pachydermatis infection was identified in an intensive care nursery, we initiated an investigation. METHODS: A case patient was defined as any infant in the intensive care nursery who had a positive culture for M. pachydermatis between October 17, 1993, and January 18, 1995. We conducted a cohort study to identify risk factors for colonization and infection with M. pachydermatis. We collected cultures from the infants and the health care workers and from the health care workers' pets, since this organism has been associated with otitis externa in dogs. RESULTS: Fifteen infants met the case definition: eight with bloodstream infections, two with urinary tract infections, one with meningitis, and four with asymptomatic colonization. The case patients were significantly more likely than the other infants to weigh 1300 g or less (15 of 65 vs. 0 of 419, P<0.001). In a multivariate analysis of infants weighing 1300 g or less, the independent risk factors for colonization or infection with M. pachydermatis were a greater severity of concomitant illness (odds ratio, 19.7; P=0.001), arterial catheterization for nine or more days (odds ratio, 29.5; P=0.027), and exposure to Nurse A (odds ratio, 74.7; P=0.004). In a point-prevalence survey, 9 additional infants, 1 health care worker, and 12 of the health care workers' pet dogs had positive cultures for M. pachydermatis. The isolates from all 15 case patients, the 9 additional colonized infants, 1 health care worker, and 3 of the 12 dogs had identical patterns of restriction-fragment-length polymorphisms. CONCLUSIONS: In this outbreak, it is likely that M. pachydermatis was introduced into the intensive care nursery on health care workers' hands after being colonized from pet dogs at home. The organism persisted in the nursery through patient-to-patient transmission.  相似文献   
5.
An implicit integration algorithm has been refined to predict the stress–strain–strength response of unsaturated soil under suction-controlled, multiaxial stress paths that are not achievable in a conventional cylindrical cell. The algorithm supports numerical analyses in a deviatoric plane by using a mixed control constitutive driver, in conjunction with a generalized Cam-Clay model that also incorporates the influence of a third stress invariant, or Lode-angle θ, within a constant-suction scheme. True triaxial data from a previously accomplished series of suction-controlled triaxial compression, triaxial extension, and simple shear tests on 10-cm cubical specimens of silty sand, were used for the tuning and validation of the refined algorithm. The elliptical Willam–Warnke surface was adopted for simulation of unsaturated soil response in three-invariant stress space. Reasonably satisfactory agreement was observed between experimental and predicted deviatoric stress versus principal strain response for different suction states, as well as between experimental and predicted strength loci in a deviatoric plane.  相似文献   
6.
PURPOSE: The purpose of this investigation was to evaluate complete denture patients at pretreatment and postinsertion, 6 months and 18 months after denture delivery in order to develop an explanatory model of successful denture therapy to better understand patient acceptance of complete dentures. MATERIALS AND METHODS: Sixty complete-denture patients treated at a dental student clinic were followed through denture therapy and for 18 months thereafter. Subjects were examined and completed pretreatment questionnaires and posttreatment interviews. Three outcome measures of denture success were tested, and factors considered substantive in achieving a successful denture outcome were examined using multivariate analyses. RESULTS: At post-insertion, 76.7% of subjects were satisfied with their dentures, 74.6% said their expectations were met, and 66.7% said they adjusted easily to their new dentures; reports at 6 and 18 months were similarly high. Logistic regression findings suggest that psychological and interpersonal factors are more important determinants of denture satisfaction than anatomic or clinical factors. CONCLUSIONS: Subject characteristics including age, gender, race, income level, education, marital status, and maxillary and mandibular anatomy were not significantly associated with denture success as defined by the three outcome measures used in this study. Although these variables may represent important co-factors in the patient's acceptance of dental services and may affect the way a patient perceives dental care outcomes, statistically significant relationships were not found within our sample. Psychosocial variables, such as pretreatment expectations, satisfaction with the dental care received, and mental health showed a stronger relationship to a successful outcome.  相似文献   
7.
Many fundamental and hot band absorption lines of 28Si35Cl+, 28Si37Cl+, 29Si35Cl+, and 30Si35Cl+ have been detectedbetween 630 and 700 cm-1 in a SiCl4/He discharge using diode laser velocity modulation spectroscopy. The datahave been fitted to give seven mass independent coefficients Ukl. The derived spectroscopic constants for 28Si35Cl+ include omegae = 678.24316(18) cm-1 and Be = 0.2870288(14) cm-1. The equilibrium internuclear distance is re =1.9439105(46) ?. The equilibrium dissociation energy calculated from Dunham's expanded Morse potential is De =49 431(57) cm-1. Copyright 1998 Academic Press.  相似文献   
8.
Currently,sorafenib is the only systemic therapy capable of increasing overall survival of hepatocellular carcinoma patients.Unfortunately,its side effects,particularly its overall toxicity,limit the therapeutic response that can be achieved.Superparamagnetic iron oxide nanoparticles (SPIONs) are very attractive for drug delivery because they can be targeted to specific sites in the body through application of a magnetic field,thus improving intratumoral accumulation and reducing adverse effects.Here,nanoformulations based on polyethylene glycol modified phospholipid micelles,loaded with both SPIONs and sorafenib,were successfully prepared and thoroughly investigated by complementary techniques.This nanovector system provided effective drug delivery,had an average hydrodynamic diameter of about 125 nm,had good stability in aqueous medium,and allowed controlled drug loading.Magnetic analysis allowed accurate determination of the amount of SPIONs embedded in each micelle.An in vitro system was designed to test whether the SPION micelles can be efficiently held using a magnetic field under typical flow conditions found in the human liver.Human hepatocellular carcinoma (HepG2) cells were selected as an in vitro system to evaluate tumor cell targeting efficacy of the superparamagnetic micelles loaded with sorafenib.These experiments demonstrated that this delivery platform is able to enhance sorafenib's antitumor effectiveness by magnetic targeting.The magnetic nanovectors described here represent promising candidates for targeting specific hepatic tumor sites,where selective release of sorafenib can improve its efficacy and safety profile.  相似文献   
9.
Dissolved organic matter represents the main reservoir of organic carbon in most aquatic ecosystems. In the present study, we determined the optical changes and the quantum yields of transient species formation for chromophoric dissolved organic matter (CDOM) samples undergoing photodegradation. The results show that the triplet states 3CDOM are potentially key players in CDOM photodegradation and that such transformations are strongly influenced by small differences in CDOM sources and sinks. In contrast, OH radicals are very unlikely to play a key role in phototransformation. These results represent an important first step in combining optical and transient species analyses to understand photodegradation processes of dissolved organic matter.  相似文献   
10.
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