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41.
Mikkelsson L Kaprio J Kautiainen H Kujala UM Nupponen H 《Scandinavian journal of medicine & science in sports》2005,15(5):329-335
The aim was to evaluate whether 40-year-old men and women are able to estimate their level of fitness compared with actual measured physical fitness. Twenty-nine men and 35 women first completed a questionnaire at home and then their physical fitness was measured at laboratory. The index of self-estimated physical fitness was calculated by summing up the scores of self-estimated endurance, strength, speed and flexibility. The index of self-estimated endurance was calculated by summing up the scores of self-estimated endurance and those of the self-estimated distance they could run, cycle, ski and walk. The index of measured physical fitness was calculated by summing up the z-scores of a submaximal bicycle ergometer test, ergojump tests (counter-movement jump and jumping in 15 s), a 30-s sit-up test, hand-grip tests and a sit-and-reach test. The correlation (Spearman) between the indices of self-estimated and measured physical fitness was 0.54 for both sexes, and that between self-estimated endurance and measured endurance was 0.53 for both sexes. Maximal oxygen uptake estimated based on submaximal ergometer test was higher among those with longer self-estimated distance of running, cycling, skiing and walking (P for linear trend <0.001). Our study shows that 40-year-old adults can estimate at group level their fitness according to different categories moderately well. They can also estimate at group level their endurance moderately well by estimating the distance they can run, cycle, ski or walk. However, in some individuals self-estimation of fitness is not in agreement with the results of fitness tests. 相似文献
42.
Platelet-derived growth factor receptor expression and amplification in choroid plexus carcinomas. 总被引:1,自引:0,他引:1
Nina N Nupponen Janna Paulsson Astrid Jeibmann Brigitte Wrede Minna Tanner Johannes E A Wolff Werner Paulus Arne Ostman Martin Hasselblatt 《Modern pathology》2008,21(3):265-270
Platelet-derived growth factor (PDGF) receptor signaling has been implicated in the development of glial tumors, but not yet been examined in choroid plexus carcinomas, pediatric tumors with dismal prognosis for which novel treatment options would be desirable. Therefore, protein expression of PDGF receptors alpha and beta as well as amplification status of the respective genes, PDGFRA and PDGFRB, were examined in a series of 22 patients harboring choroid plexus carcinoma using immunohistochemistry and chromogenic in situ hybridization (CISH). The majority of choroid plexus carcinomas expressed PDGF receptors with 6 cases (27%) displaying high staining scores for PDGF receptor alpha and 13 cases (59%) showing high staining scores for PDGF receptor beta. Correspondingly, copy-number gains of PDGFRA were observed in 8 cases out of 12 cases available for CISH and 1 case displayed amplification (six or more signals per nucleus). The proportion of choroid plexus carcinomas with amplification of PDGFRB was even higher (5/12 cases). PDGFRB amplification status and PDGF receptor beta protein expression scores were significantly correlated (P=0.01, Spearman). Expression status of PDGF receptor alpha or PDGF receptor beta was not significantly associated with progression-free survival. To conclude, expression and amplification of PDGF receptors, particularly PDGF receptor beta, are frequent in choroid plexus carcinomas, providing a first rationale for the development of treatments targeting PDGF receptor signaling in these rare malignant pediatric tumors. 相似文献
43.
The DAZLA (DAZ Like Autosomal) gene on human chromosome 3 shares a high
degree of homology with the DAZ (Deleted in AZoospermia) gene family on the
Y chromosome, a gene family frequently deleted in males with azoospermia or
severe oligospermia. The involvement of both DAZ and DAZLA in
spermatogenesis is suggested by their testis-specific expression and their
homology with a Drosophila male infertility gene, boule. Whereas male
infertility resulting from deletion of the DAZ genes on the Y chromosome
occurs sporadically, that due to a defective DAZLA gene is expected to be
inheritable. The fraction of males with idiopathic azoospermia or
oligospermia that harbour mutations in the DAZLA gene remains unknown. As a
prerequisite for mutation screening, the genomic structure of the DAZLA
gene was elucidated and found to consist of 11 exons spanning 19 kh. The
exon/intron boundaries are conserved between DAZ and DAZLA. The 5' end of
both genes are hypomethylated in spermatozoa but not in leukocytes or
placenta, consistent with the expression pattern of the genes. The genomic
structure of DAZLA paves the way for mutation detection in families with
autosomal recessive male infertility.
相似文献
44.
Organization, expression and polymorphism of the human persyn gene 总被引:13,自引:0,他引:13
Ninkina NN; Alimova-Kost MV; Paterson JW; Delaney L; Cohen BB; Imreh S; Gnuchev NV; Davies AM; Buchman VL 《Human molecular genetics》1998,7(9):1417-1424
Persyn is a recently identified member of the synuclein family with a
distinct pattern of expression during pre- and postnatal development of the
mouse peripheral and central nervous systems. As with other synucleins,
persyn is believed to be involved in the pathogenesis of human
neurodegenerative diseases. However, in contrast to other synucleins, high
levels of persyn mRNA expression were also found in advanced breast
carcinomas, suggesting an involvement of the encoded protein in breast
tumour progression. Here we have used an antibody specific to human persyn
to demonstrate that the level of this protein is increased in ageing
cerebral cortex and in breast tumours. We cloned, characterized and
sequenced the human persyn genomic locus and localized it to the long arm
of chromosome 10 in the q23.2-q23.3 region. Sequence information was used
to search for specific mutations in the protein coding regions of persyn
mRNA and the persyn gene in breast tumours and tumour cell lines. No
tumour-specific mutations were found, but two linked polymorphisms in the
coding region were detected, both in mRNA and exons III and IV of the gene.
These results suggest that development of breast tumours correlates with
overexpression of the wild-type persyn protein. Detailed characterization
of the human persyn locus is important for further studies of the
involvement of persyn in neurodegeneration and malignancy.
相似文献
45.
目的:比较采用骨形态发生蛋白人工骨植骨加骨折内固定与自体髂骨植入加骨折内固定治疗骨质疏松性转子间骨折的效果。方法:选择2003-10/2005-10桂林医学院附属医院骨科收治的Ⅲ、Ⅳ、V型骨质疏松性转子间骨折患者51例,均知情同意。实验分组:随机将病例分为2组,骨形态发生蛋白人工骨植入组26例,自体髂骨植入组25例。实验干预:采用股骨上段外侧切口,DHS或加防旋钉内固定,骨形态发生蛋白人工骨由处理后的牛松质骨与成品重组人骨形态发生蛋白2按一定比例复合而成,骨折固定后在骨折缺损处、内侧及骨折周围植骨,骨形态发生蛋白人工骨组采用骨形态发生蛋白人工骨植入,自体髂骨组取自体髂骨植入。实验评估:术后定期随访,比较二组患者的基本情况、临床效果和影像学结果(骨折愈合情况和颈干角的变化)。随访时关节功能评定参照采用黄公怡等提出的标准,分为优、良、可、差4级。髋内翻分类标准为颈干角<100°。结果:术后随访1年,51例患者全部进入结果分析。①术后X射线片观察:骨形态发生蛋白人工骨组临床愈合时间短于自体髂骨组[(94.50±22.45),(116.96±15.90)d,P<0.01];骨形态发生蛋白人工骨组术后1年颈干角大于自体髂骨组[(127.19±3.23)°,(120.4±5.22)°,P<0.01]。②髋关节功能及不良事件和副反应:骨形态发生蛋白人工骨组术后以1年髋关节功能优良率优于自体髂骨组(P<0.05);骨形态发生蛋白人工骨组髋内翻、下肢短缩(>2cm)的发生率均低于自体髂骨组[髋内翻(n):4,7;下肢短缩(n):3,5,P均<0.01];钉退出二组差异均无显著性意义(P>0.05)。结论:伴有骨质疏松的转子间骨折患者,采用骨形态发生蛋白人工骨植骨优于自体髂骨植骨,可缩短骨折愈合期,减少髋内翻等并发症的发生率,提高术后髋关节功能优良率,提示骨形态发生蛋白人工骨能替代自体髂骨植骨治疗骨质疏松性转子间骨折。 相似文献
46.
Despite the clinical importance of prostate cancer, the molecular mechanisms underlying the development and progression of prostate cancer are poorly understood. The lack of knowledge on the mechanisms has probably been one of the most important reasons why no new treatment modalities have been developed to cure the disease. Recent studies, especially those performed by comparative genomic hybridization, have revealed the frequent chromosomal alterations that most likely harbor the genes critical for the progression of prostate cancer. Such genetic aberrations include losses of 8p, 10q, 16q, and 13q as well as gains of 7p, 7q, 8q, and Xq. Unfortunately, the target genes for these alterations are, in most of the cases, not known. We have recently identified the androgen receptor (AR) gene as a target gene for the Xq12 amplification found in one-third of the hormone-refractory prostate cancer. The findings suggest that the AR gene amplification and overexpression is involved in the emergence of hormone-refractory prostate cancer. 相似文献
47.
Nazurah NN Abdul Wahid Sarah H Moppett Iain K Moppett 《Journal of the Royal Society of Medicine》2016,109(5):190-199
ObjectivesTo describe the quality of reporting and investigation into surgical Never Events in public reports.DesignSemi-quantitative and qualitative review of published Quality Accounts for three years (2011/2–2013/14). Data on Never Events were compared with previously collated Never Events rates. Quality of reported investigations was assessed using the London Protocol.SettingEnglish National Health Service.ParticipantsAll English acute hospital trusts.ResultsQuality Accounts were available for all Trusts for all three years, of which 342 referred to years when a surgical Never Event had occurred. A total of 125 of 342 (37%) accounts failed to report any or all Never Events that had occurred; 13/342 (4%) provided full disclosure; 197 (58%) reported that some investigation had taken place. Of these 197, 61 (31%) were limited in scope; 61 (31%) were categorised as detailed reports. Task and Technology factors were the commonest factor (103/211 (49%)) Identified in investigations, followed by Individual factors (48/211 (23%)). Team and Work environment factors were identified in 29/211 (14%) and 23/211 (11%), respectively. Organisational and Management 5/211 (2%) factors were rarely identified, and the Institutional context was never discussed.ConclusionsReporting of Never Events and their investigations by English NHS Trusts in their Quality Accounts is neither consistently transparent nor adequate. As with clinical error, the true root causes are likely to be organisational rather than individual. 相似文献
48.
The effect of baseline CD4 cell count and HIV-1 viral load on the efficacy and safety of nevirapine or efavirenz-based first-line HAART 总被引:9,自引:0,他引:9
van Leth F Andrews S Grinsztejn B Wilkins E Lazanas MK Lange JM Montaner J;NN study group 《AIDS (London, England)》2005,19(5):463-471
BACKGROUND: A substantial number of patients start their first-line antiretroviral therapy at an advanced stage of an HIV-1 infection. Potential differences between specific drug regimens in antiviral efficacy and safety in these patients are of major importance. METHODS: A post-hoc analysis within the randomized controlled 2NN trial comparing efficacy between regimes containing nevirapine (NVP), efavirenz (EFV), or both, in addition to stavudine and lamivudine. Primary outcome: risk of virologic failure in different strata of baseline CD4 T-lymphocyte counts and plasma HIV-1 RNA concentrations (pVL). Virologic failure: never reaching a pVL < 400 copies/ml, or a rebound to two consecutive values > 400 copies/ml. RESULTS: The risk of virologic failure was increased at very low CD4 counts (< 25 x 10(6) cells/l) compared to CD4 counts > 200 x 10(6) cells/l [hazard ratio (HR), 1.28; 95% confidence interval (CI), 0.93-1.77]. The same was seen for a pVL > or = 100,000 copies/ml compared to a lower pVL (HR, 1.20; CI, 0.96-1.50). There were no statistically significant differences between NVP and EFV in risk of virologic failure within any of the CD4 or pVL strata, although EFV performed slightly better in the low CD4 stratum. The incidence of rash in the NVP group was significantly higher in female patients with higher CD4 cell counts, while adverse events in the EFV group were not associated with CD4 cell count. CONCLUSIONS: Initial antiretroviral therapy including NVP or EFV is effective in patients with an advanced HIV-1 infection. A high baseline CD4 cell count is associated with the occurrence of rash in female patients using NVP. 相似文献
49.
Platelets were obtained from patients with various hyperlipidemias [type II, type V, lecithin-cholesterol acyltransferase (LCAT) deficiency] and hypolipidemias (abetalipoproteinemia, Tangier disease) to ascertain relationships among plasma lipids, platelet lipids, thrombin binding and thrombin-induced platelet aggregation, and to compare these data with those previously obtained on stimulus-response coupling in platelets following in vitro modification of membrane microviscosity. Washed platelets were studied for their ability to bind 125I-thrombin in the range of 10(-10) to 10(-6) mol/L (10 mU/mL to 100 U/mL) and to aggregate with thrombin at concentrations less than 10(-9) mol/L (100 mU/mL). The values for binding and aggregation in eight patients from six kindred with familial hypercholesterolemia, taken as a group, fell in the low normal range. If divided into two groups, patients with overt cardiovascular disease bound normal amounts of thrombin but were more responsive to it, whereas patients without overt cardiovascular disease bound lower amounts of thrombin but gave an aggregation response in the normal range. These results suggest that platelet hyperresponsiveness in familial hypercholesterolemia arises from an alteration in the coupling mechanism between thrombin binding and response such that platelets from patients with familial hypercholesterolemia are able to respond with lower receptor occupancy than is the case with normal platelets. Thrombin binding and aggregation were within normal ranges for platelets from abetalipoproteinemia patients (N = 4) and type V hyperlipoproteinemia (N = 2), although in the latter case the response appeared to be less at very low thrombin concentrations (less than 30 mU/mL). Thrombin binding was elevated in Tangier disease (N = 3) but with lower responsiveness at lower thrombin concentrations. Thrombin binding was also elevated in LCAT deficiency (N = 2), and one patient showed increased and another showed decreased aggregation responses. In general, increased plasma cholesterol levels resulted in increased stimulus-response coupling (type II), whereas increased triglyceride levels resulted in decreased coupling (type V, Tangier), and there was no apparent alteration in the coupling mechanism with overall reduction in plasma lipid levels as in abetalipoproteinemia. 相似文献
50.
for the NN Study Group 《HIV clinical trials》2013,14(5):254-261
AbstractObjective: As part of the large international, randomized 2NN trial, the pharmacokinetics of nevirapine in once-daily 400 mg and twice-daily 200 mg dosing regimens were investigated. Method: Treatment-naive HIV-1-infected patients were randomized to receive nevirapine 400 mg once daily or 200 mg twice daily, in combination with lamivudine and stavudine. Blood samples were collected at several time-points (day 3, weeks 1, 2, 4, 24, and 48). Differences in pharmacokinetics between once- versus twice-daily dosing were investigated with nonlinear mixed effects modelling (NONMEM). Results: In total, 2,899 nevirapine plasma concentrations were available from 578 patients. Dosage and dosing frequency did not influence clearance or volume of distribution of nevirapine, indicating linear pharmacokinetic behavior of nevirapine whether given as a single daily dose or as divided doses over 24 hours. During steady state, the Cmin was lower (3.26 mg/L vs. 4.44 mg/L; p < .001) and the Cmax was higher (7.88 mg/L vs. 6.55 mg/L; p < .001) in the once-daily arm. However, compared to total variability in nevirapine levels for both treatments, these differences were minor. During steady state, total exposure, measured as AUC24h, was comparable for both regimens (133 mg/L*h vs. 133 mg/L*h; p = .084). Conclusion: The daily exposure to nevirapine (AUC24h) was similar for the 400 mg once-daily and the 200 mg twice-daily dosing regimens. The Cmin of nevirapine is lower and the Cmax of nevirapine is higher for the once-daily regimen as compared to the twice-daily regimen. As a result, 200 mg nevirapine dosed twice daily may be preferred over 400 mg nevirapine dosed once daily. 相似文献