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101.
We have investigated the anti-inflammatory and antimicrobial effect of the lectin from Lonchocarpus sericeus seeds (LSL) in a model of infectious peritonitis in adult Wistar rats. Animals were treated with saline or LSL (10 mg kg(-1), i.v) immediately and 6 h after the induction of peritonitis via cecal ligation and single puncture. Twelve hours after surgery, animals were killed and the infectious process was monitored by total and differential count of cells from blood and peritoneal washing liquid, adenosine deaminase activity, antibiogram and the number of viable bacteria of the peritoneal cavity. LSL treatment decreased the inflammatory response evoked by the induction of peritonitis, as seen by the inhibition of neutrophil migration into peritoneal cavities, leucocytosis and reduction of adenosine deaminase activity in the peritoneal fluid. All these effects were reversed by the lectin association to N-acetyl-glucosamine. LSL in-vitro did not show any antimicrobial action, but promoted a marked decrease of the viable bacterial population in peritoneal cavities. In conclusion, LSL inhibited the inflammatory response and the bacterial colonization of infectious peritonitis in rats.  相似文献   
102.
Fifty five years after the first finding relating mood disturbances and cardiovascular diseases, there is still debate on the formation of a cogent conception embracing all the fragments of insight within the various aspects relating psychosocial stress to cardiovascular diseases. The clinical comorbidity is empirically evident, but there are ambiguous research results limiting the value of the proposed pathophysiological mechanisms. Psychosocial stress represents here any event that relates psychological phenomena to the social environment and to the associated pathophysiological changes. Stress denotes the external or environmental factors to which people are exposed, as well as the behavioural or biological reaction to it (response that some authors call "distress"). Cardiovascular diseases will be considered here only when being the consequence of chronic inflammatory disease of arteries (atherosclerosis).The question is: Are there pathophysiological reliable mechanisms relating psychosocial stress to the development of cardiovascular diseases?  相似文献   
103.
104.
Three genome-wide RNA interference screens were performed in Drosophila S2 cells to dissect the contribution of host processes to Listeria monocytogenes entry, vacuolar escape, and intracellular growth. Among the 116 genes identified, several host pathways previously unrecognized as playing a role in listerial pathogenesis were identified: knockdowns affecting vacuolar trafficking to and from the multivesicular body bypassed the requirement for the essential pore-forming toxin listeriolysin O in mediating escape from phagocytic vacuoles and knockdowns affecting either subunit of serine palmitoyltransferase, a key enzyme in ceramide and sphingolipid biosynthesis, enhanced the toxicity of listeriolysin O expressed in the host cell cytosol, leading to lack of appropriate toxin activity compartmentalization and host cell death. Genome-wide RNA interference screens using Drosophila S2 cells proved to be a powerful approach to dissect host-pathogen interactions.  相似文献   
105.
OBJECTIVE: To assess the influence of low education and illiteracy on the evaluation of dementia by the Mattis Dementia Rating Scale (MDRS). METHOD: We applied the MDRS to 62 normal elderly subjects (64-77 years), divided into five groups according to schooling, i.e., 15-16 years, 11-12 years, 8-9 years, 4 years, and illiterate. The MDRS covers the study of five subscales and the sum of their scores may represent the degree of cognitive impairment. RESULTS: A significant difference (p < 0.05) in performance on this scale was observed among the subgroups in relation to education on 12 items, 5 subscales (illiterates < all other groups and 15-16 years > 4 and 8 years of schooling, p < or = 0.001) and the total MDRS score (illiterates < all others and 4 and 8 years < 15-16 years, p < 0.001). No significant correlations where found for age and, regarding gender, the differences were significant in only one item. CONCLUSION: Education interfered with individual performance on the MDRS. Illiteracy is a determinant factor of lower MDRS scores that could generate diagnostic errors.  相似文献   
106.
Inflammatory bowel disease is associated with extra-intestinal manifestations which occur either at the same time as flares of bowel inflammation (skin and eye disease) or run a course that is independent to inflammation in the bowel (liver and some joint syndromes). It has been suggested that the skin and eye complications occur as a consequence of the recruitment of activated effector cells released from the gut into the circulation to extra-intestinal site where they cause acute damage. However, this does not explain how patients can develop primary sclerosing cholangitis many years after having their colon removed for colitis. We propose that long-lived populations of memory lymphocytes arise as a consequence of bowel inflammation and that these cells express homing receptors that direct their subsequent migration not only to the gut but also to the liver. These long-lived cells may recirculate to the liver for many years and, in the absence of a local activating stimulus, will not cause damage. However, if they are subsequently activated in the liver this will lead to the development of inflammation and tissue damage which promotes the recruitment of more mucosal lymphocytes resulting in persistent inflammation and disease. The recent findings that MAdCAM-1 and CCL25, previously thought to be restricted to the gut, are up-regulated in the liver during inflammatory liver diseases that complicate IBD support the concept that common mechanisms control lymphocyte recruitment to the inflamed liver and gut.  相似文献   
107.
Two corticotropin-releasing factor (CRF) receptor families have been identified (CRF1 and CRF2). Whereas anxiogenic-like roles for the CRF1 receptor have been identified, behavioral functions of the CRF2 receptor remain obscure. Urocortin 2 (Ucn 2), a CRF-related peptide that selectively binds CRF2 receptors, was recently identified and recognized for its central anorectic properties. The present study tested the hypothesis that the anorexigenic mode of action of Ucn 2 differed from that of ovine CRF (oCRF), a preferential CRF1 receptor agonist. The behavioral effects of intracerebroventricular administration of Ucn 2 were compared with those of oCRF in nondeprived male Wistar rats (n=102). Ucn 2 reduced 6-h food and water intake at doses that did not induce visceral illness (0.1, 1, and 10 microg), as indicated by kaolin intake. Ucn 2 retained its potent anorectic activity in rats receiving a highly palatable cafeteria diet, preferentially reducing intake of carbohydrate (CHO)-rich items while sparing intake of mixed-fat/CHO items. In contrast to Ucn 2, oCRF (10 microg) suppressed 6-h intake of cafeteria diet-fed rats without regard to macronutrient composition. Rather, oCRF most potently suppressed intake of preferred food items. Whereas oCRF had short-onset motor-activating effects, Ucn 2 had nondose-dependent, delayed-onset motor-suppressing effects. Thus, central infusion of a CRF2 receptor agonist suppressed intake of both bland and palatable diets without inducing behavioral arousal or malaise, and the profile of anorexigenic effects qualitatively differed from those of a CRF1 receptor agonist. The results suggest the existence of distinct forms of CRF1- and CRF2-mediated anorexia.  相似文献   
108.
109.
OBJECTIVE: to examine the effects and feasibility of educating and empowering older people with ischaemic heart disease using trained senior lay health mentors. DESIGN: randomised controlled trial with blinded evaluation. SETTING: Falkirk and District Royal Infirmary. Participants: inpatients and outpatients aged 60 or over attending secondary care with a diagnosis of angina or acute myocardial infarction. Three-hundred and nineteen entered and 289 completed exit assessments. The intervention group took part in mentoring groups for 1 year, meeting monthly for 2 hours, each led by two trained lay health mentors in addition to standard care. MAIN OUTCOME MEASURES: primary outcome measures were changes in coronary risk factors, medication usage and actual use of secondary care health services. Secondary outcomes were total and cardiovascular events; changes in medication compliance, non-medical support requirement, health status and psychological functioning, and social inclusion. RESULTS: there were significant improvements in a reported current exercise score (mean +0.33, +0.02 to +0.52), in the average time spent walking per week by 72 minutes (+1 to +137 minutes), and in the SF36 Physical Functioning Score (+6.1, +2.4 to +9.5). There was a 1.0% reduction in total fat (95% CI -3.0% to -0.6%) and a 0.6% reduction in saturated fat (95% CI -1.5% to -0.03%). The intervention group showed reduced outpatient attendance for coronary heart disease (-0.25 appointments, -0.61 to -0.08). Attendance rates were high. Socio-economic grouping did not affect participation. CONCLUSIONS: Lay Health Mentoring is feasible, practical and inclusive, positively influencing diet, physical activity, and health resource utilisation in older subjects with ischaemic heart disease without causing harm.  相似文献   
110.
BACKGROUND: Home hemodialysis offers potential advantages over hospital hemodialysis, including the opportunity for more frequent and/or longer dialysis sessions. Expanding home hemodialysis services may help cope with the increasing numbers of people requiring hemodialysis. METHODS: We sought comparative studies or systematic reviews of home versus hospital/satellite unit hemodialysis for people with end-stage renal failure (ESRF). Outcomes included quality of life and survival. We searched MEDLINE, EMBASE, HealthSTAR, CINAHL, PREMEDLINE, and BIOSIS. Two reviewers independently extracted data and assessed the quality of the studies included. RESULTS: Twenty-seven studies of variable quality were included. People on home hemodialysis generally experienced a better quality of life and lived longer than those on hospital hemodialysis. Their partners, however, found home hemodialysis more stressful. Four studies using a Cox proportional hazards model to compare home with hospital hemodialysis reported a lower mortality risk for home hemodialysis. Of two studies using a Cox model to compare home with satellite unit hemodialysis, one reported a similar mortality risk, whereas the other reported a lower mortality risk for home hemodialysis. CONCLUSIONS: Home hemodialysis was generally associated with better outcomes than hospital hemodialysis and (more modestly so) satellite unit hemodialysis, in terms of quality of life, survival, and other measures of effectiveness. People on home hemodialysis, however, are a highly selected group. Home hemodialysis also provides the opportunity for more frequent and/or longer dialysis sessions than would otherwise be possible. It is difficult to disentangle the true effects of home hemodialysis from such influencing factors.  相似文献   
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