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Purpose

Few studies have examined responsiveness of bioimpedance (BIA) to detect changes over time in body composition using a longitudinal design. Accuracy of BIA and skinfold thickness in estimating body composition among 39–64 year-old women was investigated using dual-energy X-ray absorptiometry (DXA) as a criterion method both cross-sectionally and during a training intervention.

Methods

97 women had percentage of fat assessed using DXA, skinfolds and eight-polar BIA using multi-frequency current. Fat mass and lean mass were estimated by DXA and BIA. Measurements were performed before and after the 21-week training intervention.

Results

At baseline relative to DXA, BIA under predicted percentage of fat (?6.50 %) and fat mass (?3.42 kg) and overestimated lean mass (3.18 kg) considerably. Also skinfold measurement under predicted percentage of fat compared to DXA, but the difference was smaller (?1.69 % units). Skinfold measurement overestimated percentage of fat at low values and underestimated at high values (r 2 = 0.535). A significant bias was detected between DXA and BIA’s estimate of change in percentage of fat, fat mass and lean mass. Compared to DXA, BIA and skinfolds underestimated the training-induced positive changes in body composition.

Conclusions

BIA and skinfold methods compared to DXA are not interchangeable to quantify the percentage of fat, fat mass and lean mass at the cross-sectional design in middle-aged women. Moreover, exercise training-induced small changes in body composition cannot be detected with BIA or skinfold method, even though DXA was able to measure statistically significant within-group changes in body composition after training.  相似文献   
44.
The International Journal of Cardiovascular Imaging - To evaluate the prevalence of aortic regurgitation (AR) and associations between the individual aortic root components and AR severity in the...  相似文献   
45.
Glycoprotein VI is a platelet collagen receptor binding to subendothelial collagen after a rupture of an atherosclerotic plaque. The GPVI gene is polymorphic with several SNPs and the T13254C polymorphism predicting amino acid substitution (serine to proline) has been associated with the risk of MI in a preliminary study. We studied the association of the GPVI T13254C with fatal myocardial infarction (MI) and coronary artery disease among the 300 men of the Helsinki Sudden Death Study (HSDS). Genotype frequencies were 77.9% for TT, 20.7% for CT and 1.4% for CC. We found a significant association (P = 0.02) between the C-allele carriers (CT or CC) and coronary thrombosis (OR 2.5, 95% CI: 1.05-6.2). There was also a tendency (P = 0.07) for an association between the C-allele and acute myocardial infarction (AMI) (OR 2.2). The average area of complicated coronary lesions was also significantly (P = 0.01) larger in carriers compared to non-carriers of the C-allele. Our findings support previous results on the role of this GPVI polymorphism, or another linked polymorphism, as a possible predictor of the risk of coronary thrombosis.  相似文献   
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Survival after non‐Hodgkin lymphoma (NHL) has increased thanks to improved treatment but NHL survivors have an increased risk of second neoplasms. The assessment of cancer risk patterns after NHL may help to quantify the late side‐effects of therapy. Poisson regression was used to estimate relative risks (RRs) and absolute incidence rates for nine solid tumours based on a nationwide cohort of 60 901 NHL survivors from Finland, Norway and Sweden. Patients were diagnosed between 1980 and 2006 and developed 6815 s neoplasms. NHL patients showed an increased risk of each of the nine investigated cancer sites: prostate and pancreas (both RRs 1·28), breast (1·37), colorectum (1·48), urinary bladder (1·52), stomach and lung (both RRs 1·87), skin (melanoma 2·27) and kidney (2·56). The RRs showed a U‐shaped relationship with time after NHL for all nine‐second cancer types. NHL diagnosis early in life was a risk factor for the development of second cancers with the exception of melanoma, but a risk excess was even observed in patients diagnosed with NHL at age 80+ years. The present study provides accurate estimates on the adverse late effects of NHL therapy, which should guide the establishment of cancer prevention strategies in NHL survivors.  相似文献   
48.
Clinicians prescribing new oral anticoagulants (OACs; dabigatran, rivaroxaban, and apixaban) should be aware of the exclusion criteria related to bleeding risks defined in published clinical studies. At least a quarter of patients currently using warfarin have an exclusion criterion that may prevent easy transition to the new OACs. In the summary of product characteristics for dabigatran, as an example, the target populations appear generalized. Due to fixed dosing and predictable pharmacology, routine laboratory monitoring of new OACs is deemed unnecessary. Under special circumstances, however, understanding the extent of thrombin or factor (F) Xa inhibition may aid in evaluating compliance and handling emergency interventions, bleeding complications, or overdoses. Although commonly available global coagulation-time assessments (prothrombin time and activated partial thromboplastin time) are insensitive, they may assist clinical management by indicating a severe accumulation of OACs; moreover, a normal thrombin time (TT) excludes a thrombin-inhibitor effect. In particular circumstances, specific assays (diluted TT, Ecarin clotting time, anti-FIIa or anti-FXa activity) may quantify the anticoagulant effect, but therapeutic ranges for dose adjustment are not yet established. Laboratory results are also influenced by clinical situation: e.g. bleed (consumption of coagulation factors) versus postoperative state (activation of coagulation). Without specific antidotes and evidence-based treatment strategies, new OACs are clinically worrisome in patients with impaired renal or liver function. Postmarketing surveillance and recording of bleeding complications (ICD-10 D68.32) are therefore of major importance.  相似文献   
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Recent studies reported mutations in the gene encoding the proline-rich transmembrane protein 2 (PRRT2) to be causative for paroxysmal kinesigenic dyskinesia (PKD), PKD combined with infantile seizures (ICCA), and benign familial infantile seizures (BFIS). PRRT2 is a presynaptic protein which seems to play an important role in exocytosis and neurotransmitter release. PKD is the most common form of paroxysmal movement disorder characterized by recurrent brief involuntary hyperkinesias triggered by sudden movements. Here, we sequenced PRRT2 in 14 sporadic and 8 familial PKD and ICCA cases of Caucasian origin and identified three novel mutations (c.919C>T/p.Gln307*, c.388delG/p.Ala130Profs*46, c.884G>A/p.Arg295Gln) predicting two truncated proteins and one probably damaging point mutation. A review of all published cases is also included. PRRT2 mutations occur more frequently in familial forms of PRRT2-related syndromes (80–100 %) than in sporadic cases (33-46 %) suggesting further heterogeneity in the latter. PRRT2 mutations were rarely described in other forms of paroxysmal dyskinesias deviating from classical PKD, as we report here in one ICCA family without kinesigenic triggers. Mutations are exclusively found in two exons of the PRRT2 gene at a high rate across all syndromes and with one major mutation (c.649dupC) in a mutational hotspot of nine cytosines, which is responsible for 57 % of all cases in all phenotypes. We therefore propose that genetic analysis rapidly performed in early stages of the disease is highly cost-effective and can help to avoid further unnecessary diagnostic and therapeutic interventions.  相似文献   
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