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41.
Homocysteine triggers mucosal microvascular activation in inflammatory bowel disease 总被引:3,自引:0,他引:3
Danese S Sgambato A Papa A Scaldaferri F Pola R Sans M Lovecchio M Gasbarrini G Cittadini A Gasbarrini A 《The American journal of gastroenterology》2005,100(4):886-895
OBJECTIVES: Increased homocysteine contributes to the pathophysiology of several chronic inflammatory diseases. Whether homocysteine could participate in mucosal inflammation in inflammatory bowel disease (IBD) has not been explored yet. Our aims were to study the levels of plasma and mucosal homocysteine in IBD patients and to assess whether homocysteine can trigger an inflammatory reaction on human intestinal microvascular endothelial cells (HIMECs). METHODS: Homocysteine was measured in the plasma, mucosal biopsy, and lamina propria mononuclear cell (LPMC) supernatants from normal and IBD subjects. HIMEC were cultured in presence of homocysteine, TNF-alpha, or folic acid, alone or in combination. Expression of vascular cell adhesion molecule 1 (VCAM-1) and intercellular cell adhesion molecule 1 was measured by flow cytometry and monocyte chemoattractant protein-1 (MCP-1) production by ELISA. Phosphorylation of p38 and p42/44 was assessed by immunoblot in HIMEC extracts. T-cell- and monocyte-HIMEC adhesion assays were used to evaluate the impact of homocysteine on leukocyte adhesion to intestinal endothelial cells. RESULTS: Patients with IBD displayed significantly higher homocysteine plasma and mucosal levels than control subjects. IBD-derived LPMC released higher homocysteine than control-derived LPMC. Treatment of HIMEC with homocysteine, and synergistically with the combination of TNF-alpha and homocysteine, triggered HIMEC inflammation, resulting in VCAM-1 up-regulation, MCP-1 production, and p38 phosphorylation. These events lead to an increased capacity of HIMEC to adhere T- and monocyte cells and were blocked by folic acid treatment. CONCLUSIONS: Homocysteine is increased in both the mucosa and plasma of patients with Crohn's disease and ulcerative colitis and contributes to the inflammatory state of the mucosal IBD endothelium. Therefore, homocysteine could play a proinflammatory role in IBD, which can be efficiently targeted by folic acid supplementation. 相似文献
42.
J M Quesada W Coopmans B Ruiz P Aljama I Jans R Bouillon 《The Journal of clinical endocrinology and metabolism》1992,75(2):494-501
The effect of age and vitamin D status on parathyroid function was studied in 129 healthy subjects between 20 and 89 yr old, with normal serum creatinine (less than 0.11 mmol/L), and living in Cordoba, Spain. Serum calcium and phosphorus as well as 25-hydroxyvitamin D (25OHD) and 1,25-dihydroxyvitamin D [1,25-(OH)2D] decreased, whereas serum alkaline phosphatase increased, with age. Serum PTH also increased significantly with age when measured with either a carboxyl-terminal (cPTH) or an intact [PTH(1-84)] assay. The increase in cPTH, however, exceeded largely the increase in PTH(1-84) (+120% and +30% in subjects above 80 yr vs. young adults, respectively). Serum PTH(1-84) was negatively correlated with serum (ionized) calcium, 25OHD, and insulin-like growth factor I (IGF-I) but not with serum 1,25-(OH)2D. Serum 1,25-(OH)2D decreased with age and was highly correlated with serum 25OHD, cPTH, and IGF-I. In multiple regression analysis 50-60% of the variation of total and free 1,25-(OH)2D could be explained by serum 25OHD, PTH(1-84), and especially IGF-I, suggesting a possible role of decreasing GH and IGF-I concentrations in the mineral homeostasis of the elderly. Calcium infusion (1.5 mg/kg body weight over 10 min) decreased serum PTH(1-84) to below normal concentrations in young adults (nadir 14% of basal concentration), whereas the nadir in elderly subjects with secondary hyperparathyroidism was only 32% of basal concentration. The relative decrease was, however, identical in both age groups when simultaneous changes in ionized calcium were taken into account. Basal serum PTH(1-84) in selected elderly subjects (50 +/- 10 ng/L or 5 +/- 1 pmol/L, n = 10) decreased significantly (2.7 +/- 0.9 pmol/L, P less than 0.01) after 3 iv injections of 1,25-(OH)2D during 1 week without changes in serum (ionized) calcium. The PTH suppressibility after calcium infusion did not further improve. In conclusion: elderly patients with normal serum creatinine had a small (+30%) but significant increase in intact serum PTH concentration but the mean concentration still remained within the normal range. The PTH secretion remained normally suppressible by acute calcium infusion. Treatment with 1,25-(OH)2D decreased basal calcium-PTH setpoint without further additional effects during calcium infusion. 相似文献
43.
The natriuretic response to the intrarenal administration of atrial natriuretic factor (ANF) is accompanied by an increase in the synthesis of prostaglandins and by a redistribution of renal blood flow from the superficial to the deep cortex. This study was undertaken to define whether prostaglandins mediate the ANF-induced redistribution of renal blood flow and if prostaglandins and renal blood flow redistribution contribute to the natriuretic actions of ANF. In anesthetized dogs, the intrarenal administration of indomethacin (10 micrograms/kg/min) or the intravenous administration of meclofenamate (5 mg/kg) completely prevented the sixfold and twofold increments in urinary prostaglandin E2 and 6-keto-prostaglandin F1 alpha excretion, respectively; it also abolished the redistribution of renal blood flow to the deep cortex. However, ANF induced a similar natriuresis before (from 53 +/- 17 to 281 +/- 48 microEq/min) and after (from 45 +/- 13 to 273 +/- 60 microEq/min) the administration of prostaglandin synthesis inhibitors. It is concluded that the ANF-induced redistribution of renal blood flow to the deep cortex is prostaglandin-mediated but that neither redistribution nor increased prostaglandin synthesis is an important mediator of ANF's natriuretic action. 相似文献
44.
45.
Clément Medrinal Guillaume Prieur Yann Combret Aurora Robledo Quesada David Debeaumont Tristan Bonnevie Francis Edouard Gravier Elise Dupuis Lozeron Jean Quieffin Olivier Contal Bouchra Lamia 《Archives of physical medicine and rehabilitation》2018,99(8):1454-1461
Objective
To evaluate the effect of quadriceps functional electrical stimulation (FES)-cycling on exertional oxygen uptake (o2) compared with placebo FES-cycling in patients with chronic obstructive pulmonary disease (COPD).Design
A randomized, single-blind, placebo-controlled crossover trial.Setting
Pulmonary rehabilitation department.Participants
Consecutive patients (N=23) with COPD Global Initiative for Chronic Obstructive Lung Disease stage 2, 3, or 4 (mean forced expiratory volume during the first second, 1.4±0.4L [50.3% predicted]) who had recently begun a respiratory rehabilitation program.Intervention
Two consecutive 30-minute sessions were carried out at a constant load with active and placebo FES-cycling.Main Outcome Measures
The primary outcome was mean o2 during the 30-minute exercise session. The secondary outcomes were respiratory gas exchange and hemodynamic parameters averaged over the 30-minute endurance session. Lactate values, dyspnea, and perceived muscle fatigue were evaluated at the end of the sessions.Results
FES-cycling increased the physiological response more than the placebo, with a greater o2 achieved of 36.6mL/min (95% confidence interval [CI], 8.9–64.3mL/min) (P=.01). There was also a greater increase in lactate after FES-cycling (+1.5mmol/L [95% CI, .05–2.9mmol/L]; P=.01). FES-cycling did not change dyspnea or muscle fatigue compared with the placebo condition.Conclusions
FES-cycling effectively increased exercise intensity in patients with COPD. Further studies should evaluate longer-term FES-cycling rehabilitation programs. 相似文献46.
Danielle Quesada Nasar U. Ahmed Kristopher P. Fennie Erica L. Gollub Boubakari Ibrahimou 《Archives of Psychiatric Nursing》2018,32(3):495-504
In the past few years we have become increasingly aware of strong associations between obesity and ADHD. Both conditions are major public health issues, affecting children, adolescents and adults alike.
Objective
This review seeks to (1) examine prior research on the association between ADHD and obesity in children and adolescents; (2) discuss mechanisms and consequent behavioral attributes to gain understanding of the path association between ADHD and obesity, (3) review studies examining the role of physical activity, medication, eating behavior and gender on the relationship between ADHD and obesity in children and adolescents.Method
PubMed, CINAHL and PsycINFO databases were used to search for studies whose subjects were children and adolescents, ages 0–17?years and whose publication years were from 2000 to 2016. After screening 31 studies were included in the review.Results
The literature suggests that there is a significant association between ADHD and obesity. Further, the inattentive and impulsive behaviors that characterize ADHD could contribute to dis-regulated eating behaviors and a lack of motivation to engage in physical activity. In addition, it is proposed that medication, gender and physical activity play a role in mediating and moderating the relationship between ADHD and obesity. 相似文献47.
48.
Ethical implications of home telecare for older people: a framework derived from a multisited participative study 下载免费PDF全文
Maggie Mort PhD Celia Roberts PhD Jeannette Pols PhD Miquel Domenech PhD Ingunn Moser PhD The EFORTT investigators 《Health expectations》2015,18(3):438-449
Context
Telecare and telehealth developments have recently attracted much attention in research and service development contexts, where their evaluation has predominantly concerned effectiveness and efficiency. Their social and ethical implications, in contrast, have received little scrutiny.Objective
To develop an ethical framework for telecare systems based on analysis of observations of telecare‐in‐use and citizens’ panel deliberations.Design
Ethnographic study (observation, work shadowing), interviews, older citizens’ panels and a participative conference.Setting
Participants’ homes, workplaces and familiar community venues in England, Spain, the Netherlands and Norway 2008–2011.Results
Older respondents expressed concerns that telecare might be used to replace face‐to‐face/hands‐on care to cut costs. Citizens’ panels strongly advocated ethical and social questions being considered in tandem with technical and policy developments. Older people are too often excluded from telecare system design, and installation is often wrongly seen as a one‐off event. Some systems enhance self‐care by increasing self‐awareness, while others shift agency away from the older person, introducing new forms of dependency.Conclusions
Telecare has care limitations; it is not a solution, but a shift in networks of relations and responsibilities. Telecare cannot be meaningfully evaluated as an entity, but rather in the situated relations people and technologies create together. Characteristics of ethical telecare include on‐going user/carer engagement in decision making about systems: in‐home system evolution with feedback opportunities built into implementation. System design should be horizontal, ‘two‐way’/interactive rather than vertical or ‘one‐way’. An ethical framework for telecare has been developed from these conclusions (Table 1). 相似文献49.
A Franco H Guidicelli C Quesada J P Laroche B Morzol C Brambilla M Aguettaz M Comet B Denis P Martin-No?l 《Archives des maladies du coeur et des vaisseaux》1979,72(8):849-856
Rheoplethysmography with occlusion (RPO) is useful in the diagnosis of deep venous thrombosis. Bilateral phlebography with cavography performed afterwards as an emergency gives information as to the embolic potential of the thrombosis and orientates treatment towards surgical interruption of the inferior vena cava. In the C.H.U. at Grenoble 83 clips, 25 umbrella filters and 2 ligatures were placed on the inferior vena cava from 1974 to 1977. Prevention of pulmonary emboli was achieved in 99% cases with lower limb embolic foci. Follow-up by RPO and isotopic phlebography showed that the course of venous thrombosis of the lower limbs seemed to be unchanged by partial interruption of the inferior vena cava, provided that elastic stockings and adequate anticoagulant therapy adapted to venous haemodynamics are used. 相似文献
50.
Recombinant interferon gamma in hairy cell leukemia, multiple myeloma, and Waldenstrom's macroglobulinemia 总被引:1,自引:0,他引:1
J R Quesada R Alexanian R Kurzrock B Barlogie S Saks J U Gutterman 《American journal of hematology》1988,29(1):1-4
Fifteen patients with multiple myeloma, five with hairy cell leukemia, and five with Waldenstrom's macroglobulinemia were treated with recombinant interferon gamma (rINF-gamma) to determine the antitumor activity of this agent. The rIFN-gamma was administered by daily intramuscular injection at doses ranging from 0.125 to 0.5 mg/m2. No responses were observed in patients with multiple myeloma, although in one patient the disease has remained stable for over 16 months. Minimal improvement in some hematologic indexes were observed in three of five patients with hairy cell leukemia. One partial remission and one minor response were documented in two of the five patients with Waldenstrom's macroglobulinemia. In five patients, an increase in normal serum immunoglobulins was observed. These results suggest that there is only minimal activity of rIFN-gamma as a single agent in neoplasms of B-cell origin. 相似文献