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91.
Hofman K Swinnen JV Claessens F Verhoeven G Heyns W 《Molecular and cellular endocrinology》2000,168(1-2):21-29
Transient cotransfection in COS-7 cells, a standard approach to demonstrate coactivation, was used to study the coactivation properties of NuRIP183, a new nuclear receptor interacting protein of 183 kDa, isolated by a yeast two-hybrid screening. Transfection with a NuRIP183 expression construct strongly increased the ligand-dependent response of reporter constructs for several nuclear receptors when compared to transfection with the empty expression vector. A more detailed study, however, revealed major changes in the expression level of the nuclear receptors in cotransfection experiments, indicating that the observed changes in receptor activity were not due to coactivation but to differences in receptor concentration caused by interference from the cotransfected expression constructs with the expression of the receptor. Such interference, which is inversely related to the length of the insert, was observed, not only in COS-7 cells but also in CV-1 and MCF-7 cells, using different transfection techniques (FuGENE-6 and calcium phosphate) and different expression vectors (pSG5, pcDNA1.1 and pIRESneo). These data cast some doubt on coactivation of nuclear receptors based on similar cotransfection experiments without measurement of receptor concentration. Moreover, it is recommended to limit the amounts of (co)transfected expression plasmid and to avoid the use of empty expression plasmid as a control. Finally, one should be aware of similar misleading results in other experimental set-ups based on cotransfection. 相似文献
92.
Jaquet JB Kalmijn S Kuypers PD Hofman A Passchier J Hovius SE 《Annals of plastic surgery》2002,49(1):82-90
Forearm and wrist injuries can result in a nonfunctional hand caused by loss of motor and sensory functions. Psychological stress is known to accompany traumatic hand injuries and may therefore affect functional outcome. The authors conducted a retrospective study of 107 patients diagnosed with a median, ulnar, or combined median-ulnar nerve injury (79% response rate) who completed a questionnaire package consisting of the Impact of Event Scale (IES); Disabilities of Arm, Shoulder, and Hand; and a questionnaire concerning return to work and time off work. In an outpatient setting, motor and sensory recovery were examined. Ninety-four percent of those studied experienced early psychological stress. Thirty-six percent of patients reported sufficient symptoms 1 month postoperatively to be classified as in need for psychological treatment (IES score > 30 points). Combined median-ulnar nerve injuries (mean, 35.0 +/- 20.3 points [standard deviation]) were accompanied by a higher psychological stress compared with single nerve injuries (median injuries: mean, 24.2 +/- 20.6 points; ulnar injuries: mean, 22.6 +/- 19.5 points; p = 0.049 and p = 0.021 respectively). Multiple linear regression adjusting for age, gender, and severity of the trauma revealed an association between the IES score and the functional symptom score (beta = 0.51; 95% confidence interval [CI], 0.35-0.65), mean time off work (beta = 0.44; 95% CI, 0.25-0.75), and motor recovery (grip: beta = 0.37; 95% CI, 0.09-0.65; tip-pinch: beta = 0.46; 95% CI, 0.13-0.80). Patients with higher scores on the IES were found to be at increased risk for incapacity for work (odds ratio, 3.32; 95% CI, 1.60-6.91). Higher education was found to be a protecting variable for posttraumatic psychopathology (beta = -0.23; 95% CI, -6.05--0.246). This study demonstrated a high level of early posttraumatic psychological stress after forearm and wrist nerve injuries. These data provide evidence that functional outcome and work resumption are influenced negatively by early psychological stress, independent from severity of the somatic trauma. This indicates that outcome after upper extremity nerve injuries may be influenced positively by psychological intervention. 相似文献
93.
The effect of bovine colostrum supplementation on exercise performance in elite field hockey players
Hofman Z Smeets R Verlaan G Lugt Rv Verstappen PA 《International journal of sport nutrition and exercise metabolism》2002,12(4):461-469
In a double-blind, randomized, placebo-controlled study, we investigated the effect of 8 weeks of supplementation with bovine colostrum (Intact) on body composition and exercise performance (5 x 10-m sprint, vertical jump, shuttle-run test, and suicide test). Seventeen female and 18 male elite field hockey players, including players from the Dutch national team, received either 60 g of colostrum or whey protein daily. The 5 x 10-m sprint test performance improved significantly (p =.023) more in the colostrum group [0.64 +/- 0.09 s (mean +/- SEM)] compared to the whey group (0.33 +/- 0.09 s). The vertical jump performance improved more in the colostrum group (2.1 +/- 0.73 cm) compared to the whey group (0.32 +/- 0.82 cm). However, this was not statistically significant (p =.119). There were also no significant differences in changes in body composition and endurance tests between the 2 groups. It is concluded that in elite field hockey players, colostrum supplementation improves sprint performance better than whey. However, there were no differences with regard to body composition or endurance performance. 相似文献
94.
Maitland-van der Zee AH Stricker BH Klungel OH Kastelein JJ Hofman A Witteman JC Breteler MM Leufkens HG van Duijn CM de Boer A 《Pharmacogenetics》2002,12(8):647-653
We aimed to assess whether the effectiveness of statins in the prevention of myocardial infarction, stroke and total mortality is influenced by apolipoprotein E (apoE) genotype in an elderly population. We used data from the Rotterdam Study, a prospective population-based cohort study in the Netherlands which started in 1990 and included 7983 subjects aged 55 years and older. Subjects who were treated with cholesterol lowering drugs at baseline or with a serum total cholesterol > or = 6.5 mmol/l at baseline were included. We compared the incidence of myocardial infarction, stroke and total mortality in subjects who received > or = 2 years of statin treatment with that in subjects who had been treated for less than 2 years, and in untreated subjects, using a Cox proportional hazard model with cumulative statin use defined as time-dependent covariates. The adjusted relative risk of all-cause mortality was 0.79 [95% confidence interval (CI) 0.51-1.22] and of myocardial infarction and stroke 0.50 (95% CI 0.28-0.91) for subjects treated with statins for > or = 2 years compared to untreated subjects. The adjusted relative risks for subjects with the epsilon4 allele were 0.91 (95% CI 0.45-1.84) for all-cause mortality and 0.63 (95% CI 0.23-1.78) for myocardial infarction and stroke. In subjects without the epsilon4 allele, adjusted relative risks were 0.71 (95% CI 0.41-1.24) for all-cause mortality and 0.46 (95% CI 0.22-0.95) for myocardial infarction and stroke. We found a protective effect of statins on the risk of myocardial infarction and stroke that was independent of apoE genotype. The protective effect of statins on total mortality was not statistically significant, but did not seem to differ between subjects with different apoE genotypes. 相似文献
95.
Rosa A Marcelis M Suckling J Hofman P Bullmore E Delespaul P Fañanás L van Os J 《Comprehensive psychiatry》2003,44(6):459-461
The origins of cerebral abnormalities in psychotic patients remain unknown. Dermatoglyphics are suitable markers of prenatal injury due to their fetal ontogenesis and their susceptibility to some of the factors that also affect cerebral development. In a previous study, positive associations between brain volumetric measures and a dermatoglyphic marker, the ab-ridge count, were reported. The present study is an attempt to replicate that finding in an independent sample. Magnetic resonance imaging (MRI) scans and dermatoglyphic measures were available for 29 schizophrenia patients (Research Diagnostic Criteria [RDC] criteria) and 26 unrelated healthy controls. The images were processed using an automated procedure, yielding volumes of total grey matter, white matter, cerebrospinal fluid (CSF), and total brain volume. The ab-ridge count was not positively associated with brain volumes in either patients or controls. The present findings do not support the hypothesis that the changes in brain volume seen in patients with schizophrenia are of prenatal origin. 相似文献
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99.
A simple method for isolation and characterization of mouse brain microvascular endothelial cells 总被引:8,自引:0,他引:8
Brain endothelial cells, a site of the blood-brain barrier in vivo, regulate a number of physiological and pathophysiological processes in the brain including transport of nutrients, export of critical toxins, transmigration of circulating leukocytes and formation of new blood vessels. In this report, we describe a simple and reproducible method to isolate pure (>99%), functionally active endothelial cells from small quantities of adult mouse brain tissue. In vitro, these cells express typical phenotypic markers of differentiated brain endothelium such as von Willebrand factor, multiple drug resistant protein and glucose transporter-1, demonstrate uptake of acetylated low-density lipoprotein, and possess morphological and ultrastructural characteristics of microvascular endothelium. They form tight junctions and capillary-like tubes when stimulated by growth factors in an in vitro angiogenesis assay. In response to tumor necrosis factor-alpha, isolated mouse brain endothelial cells (MBEC) express vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1). The protocol described here provides an effective and reliable method to isolate pure cerebral endothelium from adult mouse brain that should offer a useful tool for studying the role of altered vascular biology in mice with genetically manipulated brain disorders. 相似文献
100.
Homocysteine, silent brain infarcts, and white matter lesions: The Rotterdam Scan Study 总被引:9,自引:0,他引:9
Vermeer SE van Dijk EJ Koudstaal PJ Oudkerk M Hofman A Clarke R Breteler MM 《Annals of neurology》2002,51(3):285-289
Silent brain infarcts and white matter lesions are frequently seen on magnetic resonance imaging in healthy elderly people and both are associated with an increased risk of stroke and dementia. Plasma total homocysteine may be a potentially modifiable risk factor for stroke and dementia. We examined whether elevated total homocysteine levels are associated with silent brain infarcts and white matter lesions. The Rotterdam Scan Study is a population-based study of 1,077 people aged 60 to 90 years who had cerebral magnetic resonance imaging. The cross-sectional relation of total homocysteine with silent infarcts and white matter lesions was analyzed with adjustment for cardiovascular risk factors. The mean plasma total homocysteine level was 11.5 micromol/l (standard deviation 4.1). The risk of silent brain infarcts increased with increasing total homocysteine levels (odds ratio 1.24/standard deviation increase, 95% confidence interval 1.06-1.45). The severity of periventricular white matter lesions and extent of subcortical white matter lesions were also significantly associated with total homocysteine levels, even after excluding those with silent brain infarcts. The overall risk of having either a silent brain infarct or severe white matter lesions was strongly associated with total homocysteine levels (odds ratio 1.35/standard deviation increase, 95% confidence interval 1.16-1.58). We concluded that total homocysteine levels are associated with silent brain infarcts and white matter lesions independent of each other and of other cardiovascular risk factors. 相似文献