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81.
82.
Association of risk of abnormal bleeding with degree of serotonin reuptake inhibition by antidepressants 总被引:2,自引:0,他引:2
Meijer WE Heerdink ER Nolen WA Herings RM Leufkens HG Egberts AC 《Archives of internal medicine》2004,164(21):2367-2370
BACKGROUND: Serotonin plays a role in platelet aggregation. Because antidepressants influence blood serotonin levels, their use may be associated with an increased risk of abnormal bleeding. However, previous studies were inconclusive regarding this association. The aim of this study was to estimate the risk of abnormal bleeding associated with the use of antidepressants and to establish the relationship between serotonin reuptake inhibition and the risk of bleeding. METHODS: We used data collected from 1992 through 2000 to conduct a nested case-control study of a cohort of more than 64 000 new antidepressant users. Cases were identified as all patients hospitalized for a primary diagnosis of abnormal bleeding, and they were matched with controls for age and sex. We classified exposure according to the degree (high, intermediate, or low) of serotonin reuptake inhibition and performed logistic regression analysis to calculate odds ratios. RESULTS: There were 196 cases of abnormal bleeding. The risk of hospitalization increased with the use of inhibitors providing intermediate (odds ratio, 1.9; 95% confidence interval, 1.1-3.5) and high degrees of serotonin reuptake inhibition (odds ratio, 2.6; 95% confidence interval, 1.4-4.8). CONCLUSIONS: In a large population of new antidepressant users we found a significant association between degree of serotonin reuptake inhibition by antidepressants and risk of hospital admission for abnormal bleeding as the primary diagnosis. An increased risk of abnormal bleeding was strongly associated with the degree of serotonin reuptake inhibition. 相似文献
83.
de Ronde W van der Schouw YT Pierik FH Pols HA Muller M Grobbee DE Gooren LJ Weber RF de Jong FH 《Clinical endocrinology》2005,62(4):498-503
OBJECTIVE: It is generally accepted that SHBG decreases the bioavailability and activity of testosterone (T). In in vitro experiments increased levels of SHBG will be associated with decreased levels of non-SHBG bound testosterone (non-SHBG-T). However, in vivo SHBG can alter both production and clearance rates and thus plasma levels of T. DESIGN AND PATIENTS: In order to study the effect of SHBG on the levels of non-SHBG-T in vivo in the presence of an active hypothalamo-pituitary-gonadal (HPG) axis we conducted a cross sectional study in 400 healthy adult men with an age range of 40-80 years and in 106 newborn boys. MEASUREMENTS: In both groups, regression coefficients (beta) and partial correlation coefficients (r) were calculated for the relationship between SHBG and T or non-SHBG-T. Adult men were divided into age groups per decade (40-50 years, 51-60 years, 61-70 years and 71-80 years) to study possible differences in the impact of SHBG on the level of non-SHBG-T throughout ageing. RESULTS: Higher levels of SHBG were associated with higher levels of total testosterone in neonates (beta = 0.02 +/- 0.004, r = 0.44, P < 0.001) but not with non-SHBG-T (beta = -0.001 +/- 0.001, r = 0.05, P = 0.52). In adult men there was a significant age related increase in levels of SHBG and an age-related decrease of both total and non-SHBG-T. Higher SHBG was strongly associated with higher total testosterone in all age groups (beta = 0.26, 0.26, 0.26 and 0.23 for 40-50 years, 51-60 years, 61-70 years and 71-80 years, respectively, P < 0.001 for all age groups). Higher SHBG was not or only slightly associated with higher non-SHBG-T beta = 0.02 (P = 0.32), beta = 0.04 (P = 0.03), beta = 0.04 (P = 0.02) and beta = 0.02 (P = 0.16) for 40-50 years, 51-60 years, 61-70 years and 71-80 years, respectively. CONCLUSIONS: In contrast to general belief, SHBG levels barely influence levels of non-SHBG-bound testosterone both in male newborns and healthy adult men: the influence, if any, is positive. Consequently the age related increase of SHBG does not account for the age related decline in non-SHBG-T in healthy adult men. 相似文献
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86.
Human adult bone marrow mesenchymal stem cells repair experimental conduction block in rat cardiomyocyte cultures. 总被引:3,自引:0,他引:3
Saskia L M A Beeres Douwe E Atsma Arnoud van der Laarse Dani?l A Pijnappels John van Tuyn Willem E Fibbe Antoine A F de Vries Dirk L Ypey Ernst E van der Wall Martin J Schalij 《Journal of the American College of Cardiology》2005,46(10):1943-1952
OBJECTIVES: We evaluated whether human adult bone marrow-derived mesenchymal stem cells (hMSCs) could repair an experimentally induced conduction block in cardiomyocyte cultures. BACKGROUND: Autologous stem cell therapy is a novel treatment option for patients with heart disease. However, detailed electrophysiological characterization of hMSCs is still lacking. METHODS: Neonatal rat cardiomyocytes were seeded on multi-electrode arrays. After 48 h, abrasion of a 200- to 450-microm-wide channel caused conduction block. Next, we applied adult hMSCs (hMSC group, n = 8), human skeletal myoblasts (myoblast group, n = 7), rat cardiac fibroblasts (fibroblast group, n = 7), or no cells (control group, n = 7) in a channel-crossing pattern. Cross-channel electrical conduction was analyzed after 24 and 48 h. Intracellular action potentials of hMSCs and cardiomyocytes were recorded. Immunostaining for connexins and intercellular dye transfer (calcein) assessed the presence of functional gap junctions. RESULTS: After creation of conduction block, two asynchronously beating fields of cardiomyocytes were present. Application of hMSCs restored synchronization between the two fields in five of eight cultures after 24 h. Conduction velocity across hMSCs (0.9 +/- 0.4 cm/s) was approximately 11-fold slower than across cardiomyocytes (10.4 +/- 5.8 cm/s). No resynchronization occurred in the myoblast, fibroblast, or control group. Intracellular action potential recordings indicated that conduction across the channel presumably occurred by electrotonic impulse propagation. Connexin-43 was present along regions of hMSC-to-cardiomyocyte contact, but not along regions of cardiomyocyte-to-myoblast or cardiomyocyte-to-fibroblast contact. Calcein transfer from cardiomyocytes to hMSCs was observed within 24 h after co-culture initiation. CONCLUSIONS: Human mesenchymal stem cells are able to repair conduction block in cardiomyocyte cultures, probably through connexin-mediated coupling. 相似文献
87.
M. C. Kamback Ph. D. Willem G. A. Bosma M.D. Burton C. D'Lugoff M.D. M.P.H. 《Addiction (Abingdon, England)》1977,72(2):171-176
Review af existing treatment methods coupled with extensive clinical contact with outpatient methadone maintenance clients suggests that, the primary difficulty in treatment u nut in the chemical properties af the drug “per se” but rather what the drug represents – a sustaining familial life style system. Item analysis of Minnesota Multiphasic Personality Inventory (MMPI) profiles indicates that social deviance is incorporated as an adopted life style which extremely resistant to change. The tenacity with which the individual dings to the drug abuse life style is an indicant of the support provided by the drug culture and is indicative of the amount of support which must be provided before any permanent change can be effected. 相似文献
88.
Peter W. de Leeuw Willem H. Birkenhäger 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》1997,10(6):803-808
Summary This paper reviews the effects of antihypertensive drugs on various aspects of renal function such as renal hemodynamics, sodium excretion and microalbuminuria. The discussion also includes the renin-angiotensin system. It is concluded that most agents reduce renal vascular resistance, at least in patients who respond with a drop in blood pressure. Microalbuminuria usually also falls, although this effect may be variable. Changes in renin and sodium excretion depend upon the type of drug used. With the present state of knowledge, it is not possible to define which type of treatment is most beneficial for the kidney in the long run. 相似文献
89.
Long-term remission from life-threatening hypercoagulable state associated with lupus anticoagulant (LA) following rituximab therapy 总被引:3,自引:0,他引:3
Rituximab, a chimeric monoclonal CD20 antibody, is useful in the treatment of B-cell lymphomas and certain autoimmune diseases. We report a successful outcome of rituximab for life threatening hypercoagulable state associated with lupus anticoagulant (LA). A 30-year-old woman initially presented 10 years ago with DVT and positive serology for SLE and LA. While on Coumadin, she suffered from recurrent DVT in the legs and arms, pulmonary emboli, Budd-Chiari syndrome, mesenteric vein thrombosis, bone infarcts, recurrent strokes, and chronic ITP. All measures including plasmapheresis and monthly IV cyclophosphamide were of no benefit. She was recently admitted with spontaneous subdural hematoma with INR of 3.8. Upon discontinuation of anticoagulation for surgical drainage, she developed acute abdomen from thrombosis and recurrent DVT. Because she had failed prior standard measures, 4 weekly infusions of rituximab (375 mg/m2) were given following 2 rounds of plasmapheresis. Subsequently, she made a remarkable recovery over the next month and has been free of thrombosis on Coumadin for over 15 months. LA, IgM antibodies to cardiolipin, and B2GP1 were consistently positive. After rituximab therapy, LA became negative and IgM antibodies to cardiolipin decreased and ITP went into remission. Rituximab induced a lasting remission in a woman suffering from life-threatening hypercoagulable state associated with LA. Her clinical remission was associated with disappearance of LA. 相似文献
90.
Mariette C. Lodder Glenn Haugeberg Willem F. Lems Till Uhlig Ragnhild E. Orstavik Piet J. Kostense Ben A. C. Dijkmans Tore K. Kvien Anthony D. Woolf 《Arthritis care & research》2003,49(2):209-215