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41.
Pelvic floor maximal strength using vaginal digital assessment compared to dynamometric measurements
Morin M Dumoulin C Bourbonnais D Gravel D Lemieux MC 《Neurourology and urodynamics》2004,23(4):336-341
AIM: To compare vaginal digital assessment with dynamometric measurements for determining the maximal strength of the pelvic floor muscles (PFM). MATERIALS AND METHODS: Eighty-nine women aged between 21 and 44 participated in the study. An experienced physiotherapist evaluated the maximal strength of the PFM of these women using the modified Oxford grading system (six categories, range 0-5) and dynamometric measurements. The mean maximal forces obtained for all women with the instrumented speculum for each category of digital assessment were compared using ANOVAs. Spearman's rho coefficients were calculated to assess the correlation between the dynamometric and the digital assessments. RESULTS: According to their symptoms and pad test results, 30 women were continent and 59 had stress urinary incontinence (SUI). Based on dynamometric measurements, important overlaps were observed between each category of digital assessment. The ANOVAs indicated that force values differ across categories (F = 10.08; P < 0.001), although contrast analyses revealed no differences in the mean maximal forces between adjacent digital-assessment categories (1-2, 2-3, 3-4, 4-5). Mean force values differed significantly only between non-adjacent levels in digital assessment, for example, between 1 and 3; 1 and 4; 1 and 5; 2 and 4; 2 and 5 (P < 0.05). Significant correlations were found between the two measurements with coefficients of r = 0.727, r = 0.450, and r = 0.564 for continent, incontinent, and all women, respectively (P < 0.01). CONCLUSIONS: Even if the dynamometric mean forces of the PFM increased across subsequent categories of digital assessment, the force values between two adjacent categories do not differ. This limitation of digital assessment should be considered by clinicians and researchers when choosing treatment orientation and evaluating treatment outcomes. 相似文献
42.
THREE DEFINITIONS: The metabolic or X syndrome is defined by an association of metabolic anomalies leading to an increased risk of cardiovascular complications. Today, there are at least 3 definitions of X syndrome: those of WHO, EGIR and NCEP. To varying degrees they associate increased abdominal fat, hypertension, glucose tolerance abnormality (ranging from hyperinsulinism to diabetes), and hypertriglyceridemia with low HDL cholesterol. FROM AN EPIDEMIOLOGICAL POINT OF VIEW: The prevalence of metabolic syndrome depends on the definition used and varies with the country or ethnic group considered. About 25% of the US and 10% of the French adult populations are concerned. THE RISK OF COMPLICATIONS: According to clinical trials, people with metabolic syndrome have a 2 to 4-fold increase in risk for coronary heart disease. Some of them have a particularly high risk (association of most features of the syndrome, association of an increased waist circumference and hypertriglyceridemia, presence of biological markers such as elevated C-reactive protein or microalbuminuria). Metabolic syndrome is also associated with a 4-fold increase in risk for developing diabetes. 相似文献
43.
GENERAL PRINCIPLES: The general progression throughout the world in type 2 diabetes has lead medical Authorities to develop mass screening but also prevention measures, notably for "high-risk" subjects such as those exhibiting a metabolic syndrome. Studies on the topic have shown that preventing type 2 diabetes was possible via lifestyle changes, possibly in association with pharmacological therapy (metformine, acarbose, thiazolidinediones, orlistat). The other therapeutic stakes in the context of the metabolic syndrome also concern the management of all identified cardiovascular risk factors. REGARDING HYPERTENSION: there are currently no specific recommendations available in the framework of metabolic syndrome, with regard to lowering blood pressure and how to obtain it. However there is evidence that patients may benefit from the strict control of blood pressure (< or =130/85 mm Hg). REGARDING DYSLIPIDEMIA: LDL cholesterol remains the main target, with a goal depending on individual cardiovascular risk (<1 or 1.30 g/l in the case of metabolic syndrome). Statins are of major interest in this context. However, it is also established that normalisation of triglycerides and HDL cholesterol contributes to the improvement of cardiovascular Issues. The respective indications for fibrates or fibrate/statin associations still need to be defined in primary as in secondary prevention. 相似文献
44.
Lee BJ Huang MC Chung LJ Cheng CH Lin KL Su KH Huang YC 《European journal of clinical nutrition》2004,58(3):481-487
OBJECTIVE: To investigate whether vitamin B(6) supplementation had a beneficial effect on lowering fasting plasma homocysteine concentrations in coronary artery disease (CAD) patients. DESIGN: A single-blind intervention study. SETTING: The study was performed at the Taichung Veterans General Hospital, the central part of Taiwan. SUBJECTS: A total of 50 subjects were identified by cardiac catheterization to have at least 70% stenosis of one major coronary artery. In all, 42 patients successfully completed this study. INTERVENTIONS: Patients were randomly assigned to one of five groups and treated with a daily dose of placebo (n=8), 5 mg vitamin B(6) (n=8), 10 mg vitamin B(6) (n=8), 50 mg vitamin B(6) (n=9), or 5 mg folic acid combined with 0.25 mg vitamin B(12) (n=9) for 12 weeks. MAIN OUTCOME MEASURES: Nutrient intakes were recorded by using 24-h diet recalls when patients returned to the cardiology clinic before the intervention (week 0) and at week 12. Vitamin B(6) status was assessed by direct measures (plasma pyridoxal 5'-phosphate) and indirect measures (erythrocyte alanine and aspartate aminotransaminase activity coefficient). Fasting plasma homocysteine, serum folic acid, and vitamin B(12) were measured. RESULTS: Fasting plasma homocysteine concentration did not respond to high or low doses of vitamin B(6) when compared with a placebo treatment after 12 weeks of supplementation. The mean fasting plasma homocysteine concentration, however, decreased significantly after 12 weeks of folic acid combined with vitamin B(12) supplementation (P=0.047). Further, within group, mean fasting plasma homocysteine concentration was nonsignificantly increased by 25.5, 16.2, and 18.3% in placebo, 10 mg/day and 50 mg/day vitamin B(6) supplemented groups, respectively; whereas folic acid combined with vitamin B(12) supplementation significantly reduced fasting plasma homocysteine concentration by 32% (P<0.001). CONCLUSIONS: Our results indicate that vitamin B(6) supplementation alone is less effective than folic acid combined with vitamin B(12) in lowering plasma homocysteine concentrations in CAD patients. SPONSORSHIP: This study was supported by the National Science Council, Taiwan, Republic of China (NSC-91-2320-B-040-023). 相似文献
45.
Schwaller B Tetko IV Tandon P Silveira DC Vreugdenhil M Henzi T Potier MC Celio MR Villa AE 《Molecular and cellular neurosciences》2004,25(4):36-663
Networks of GABAergic interneurons are of utmost importance in generating and promoting synchronous activity and are involved in producing coherent oscillations. These neurons are characterized by their fast-spiking rate and by the expression of the Ca(2+)-binding protein parvalbumin (PV). Alteration of their inhibitory activity has been proposed as a major mechanism leading to epileptic seizures and thus the role of PV in maintaining the stability of neuronal networks was assessed in knockout (PV-/-) mice. Pentylenetetrazole induced generalized tonic-clonic seizures in all genotypes, but the severity of seizures was significantly greater in PV-/- than in PV+/+ animals. Extracellular single-unit activity recorded from over 1000 neurons in vivo in the temporal cortex revealed an increase of units firing regularly and a decrease of cells firing in bursts. In the hippocampus, PV deficiency facilitated the GABA(A)ergic current reversal induced by high-frequency stimulation, a mechanism implied in the generation of epileptic activity. We postulate that PV plays a key role in the regulation of local inhibitory effects exerted by GABAergic interneurons on pyramidal neurons. Through an increase in inhibition, the absence of PV facilitates synchronous activity in the cortex and facilitates hypersynchrony through the depolarizing action of GABA in the hippocampus. 相似文献
46.
The metabolic syndrome is a complex disorder characterized by an atherogenic dyslipidemia resulting from the interaction between genetic and nutritional factors. The objective of this study was to examine in a cohort of 720 adults participating in the Québec Family Study (QFS) whether dietary fat interacts with the P12A polymorphism in the gene encoding the peroxisome proliferator-activated receptor-gamma (PPAR-gamma), a nuclear factor that regulates lipid and glucose homeostasis. Carriers of the A12 allele had a higher body mass index (BMI), waist circumference, fat mass as well as subcutaneous adipose tissue and visceral adipose tissue (VAT) areas both assessed by computed tomography than P12/P12 homozygotes. Total fat and saturated fat intakes estimated from a 3-day food record were significantly correlated with several components of the metabolic syndrome in P12/P12 homozygotes. None of these expected associations were observed among carriers of the A12 allele. Furthermore, in a model including the PPAR-gamma P12A polymorphism, fat intake, age and gender, PPAR-gamma P12A and its interaction with fat intake were associated with BMI and waist circumference. Similar results were obtained when saturated fat intake replaced total fat intake into the model. When the two genotype groups were further classified into quartiles of total fat or saturated fat intake and their characteristics compared, an increase in fat intake was associated with an increase in waist circumference in P12/P12 homozygotes but not in A12 carriers. There was no difference in the waist circumference in carriers of the A12 allele whether the fat or the saturated fat intake was high or low. These results suggest that the PPAR-gamma P12A polymorphism can modulate the association between dietary fat intake and components of the metabolic syndrome. 相似文献
47.
Poirot C Martelli H Lichtblau I Dhedin N Abirached F Faraguet C Vacher-Lavenu MC 《Journal de gynecologie, obstetrique et biologie de la reproduction》2002,31(8):717-723
Longer survival after anticancer treatment has lead to concern about the long-term adverse effects. Altered fertility is of particular importance. Before sterilizing treatment, three non-exclusive methods can be proposed to preserve female fertility: in vitro fertilization followed by cryopreservation of embryos, cryopreservation of mature ovocytes, cryopreservation of ovarian tissue. The method or methods chosen will depend on the age of the patient, here marital status, the urgency of the treatment, and the type of disease. Embryo cryopreservation is a routine practice in medically assisted reproduction centers, while cryopreservation of mature ovocytes and ovarian tissue is still in the experimental phase. It is known however that mature ovocytes can be used after cryopreservation. Cyropreservation of ovarian tissue is a more difficult problem. To date, there have not been any pregnancies or births after freezing-thawing of human ovarian tissue. This tissue could be used in two ways: autograft and in vitro folliculo-ovocyte maturation. Despite the uncertainty concerning use, women cryopreservation of ovarian tissue quite well. 相似文献
48.
Gérard AC Denef JF Many MC Gathy P de Burbure C van den Hove MF Coppée F Ledent C Colin IM 《The Journal of endocrinology》2003,177(2):269-277
Tissue heterogeneity and nodule formation are hallmarks of thyroid growth. This is accounted for by the clonality theory that acknowledges different individual cellular abilities to respond to trophic stimuli. In order to test the hypothesis that functional and mitotic properties of thyrocytes could be influenced by paracrine interactions with neighbour endothelial cells, studies were conducted in both mouse and human goitre models. In the first part of the study, homogenous goitres in C57 black mice were compared with heterogeneous goitres in transgenic hyperthyroid mice expressing the A2 adenosine receptor (Tg-A2aR). The second part of the study concentrated on comparing human thyroid tIssue of control individuals and of patients with Graves' disease. The rate of cell division was evaluated by immunohistochemical detection of cells positive for proliferating cell nuclear antigen (PCNA). Their spatial distribution was then correlated with immunohistochemical cellular expression of growth- and vasoactive-related factors (fibroblast growth factor-2, transforming growth factor-beta, endothelin-1, vascular endothelial growth factor, nitric oxide synthase III), and with microcirculation expansion. Observations were made on digitalised images of histological serial sections. The nearest-neighbour method was used to distinguish between random or clustered distribution. PCNA-positive cells were both randomly and uniformly distributed in homogenous goitres from C57 black mice, and were clustered in tIssue areas identified as papillary and hyperplastic zones in heterogeneous goitres from Tg-A2aR mice. However, they were absent in the so-called compact cellular zones featuring resting cells. Moreover, whereas papillary and hyperplastic zones were highly vascularised, compact zones were nearly free of microvessels. Spatial distribution of dividing cells was positively correlated with the expression of growth-related factors. A similar pattern was observed in the thyroids of patients with Graves' disease. In accordance with the recent demonstration of the presence of angiofollicular units in the thyroid, these data strongly support the hypothesis that functional and mitotic properties of each single thyrocyte, likely to be responsible for growth heterogeneity of hyperplastic glands, may be adjusted at tIssue level by specific interactions with neighbour endothelial cells that, in turn, could alter the mitotic rate of thyrocytes through paracrine signals. 相似文献
49.
50.
AIMS: The aim of this study was to design and develop a dynamometer providing a direct measurement of pelvic floor muscle (PFM) strength. MATERIALS AND METHODS: Two pairs of strain gauges were mounted on the moveable branch of a dynamometric speculum allowing measurements at different vaginal apertures. Linearity, repeatability, independence of the site of application of the resultant force to the lower branch of the speculum and hysteresis were tested by means of in vitro calibration studies. RESULTS: The linearity proved excellent over a range of 0-15 N with regression coefficients close to unity between imposed loads and voltage outputs. The slopes and intercepts of the regression lines were not significantly different between repeated sessions, indicating the high reliability of these in vitro measurements. The slopes and intercepts of the calibrations, using the same repertoire of loads imposed at three locations on the moving branch of the dynamometer, were not significantly different, confirming that the force measurement is independent of the site of the force application. Hysteresis was considered to be minimal. CONCLUSIONS: This study demonstrates that the dynamometer provides reliable measurements. The new device thus appears to have conceptual and measuring advantages over conventional methods and seems to be a very promising instrument for measuring pelvic floor strength. 相似文献