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341.
The plasminogen activation cascade is thought to play a critical role in labour-associated remodelling events, such as fetal membrane rupture and placental separation. The aim of this study was to quantify, by Northern analysis, the gene expression of urokinase plasminogen activator (UPA), urokinase receptor (UPAR) and plasminogen activator inhibitor type-2 (PAI-2) in human gestational tissues. Amnion, choriodecidua and placenta were collected from women before, during and after spontaneous-onset labour at term. The expression of UPAR mRNA was significantly (P < 0.05) increased in amnion tissue during and after labour and delivery, compared with the before-labour group. In contrast, UPAR gene expression in choriodecidua and placenta was not significantly altered in association with labour onset. PAI-2 mRNA expression was also significantly (P < 0.05) increased in amnion after labour. No statistically significant differences were observed in choriodecidua or placenta PAI-2 mRNA with labour onset. Neither was any significant effect of labour status on UPA mRNA identified in any of the tissues examined. This study is the first to describe a significant increase in UPAR and PAI-2 gene expression in human amnion tissue with labour. These data are consistent with the hypothesis that, during labour, up-regulation of UPAR expression in amnion serves to localize active UPA at the cell surface, thereby increasing proteolytic activity in fetal membranes. Increased PAI-2 in amnion after labour may provide a regulatory 'switch' to cease further proteolysis in this tissue type. In conclusion, the data obtained support the proposal that the plasminogen activation cascade contributes to the rupture of fetal membranes during active labour.   相似文献   
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Increasing the haemoglobin concentration ([Hb]) improves the oxygen transport capacity but it also increases the viscosity of the blood. The influence of changes in [Hb] and viscosity on submaximal exercise capacity and maximal aerobic power was investigated in eight healthy males in varying states of training and with a normal resting [Hb] ([Hb]r), ranging from 123 to 178 g]-1. The subjects were venesected five times (450 ml per unit) and exercise tests were performed in the anaemic state. After 5–7 weeks, when [Hb] had returned to the ‘normal’ value, a stepwise re-transfusion of three to five units of blood was performed with exercise tests after each transfusion. The [Hb]r was 137 ± 15 g l-1 in the anaemic state (A) and 170 ± 16 g l-1 after the last re-transfusion (LT). The Vo2max rose from 3.94 ± 0.35 in A to 4.68 ± 0.30 1 min-1 after LT. Individual regression lines for [Hb] and Vo2max revealed a mean increase in Vo2max of 19 ± 6 ml min-1 per g l-1 change in [Hb]. This value did not differ between individuals with high and low normal [Hb]. Furthermore, in intra-individual comparisons the relationship between [Hb] and Vo2max in high and low individual [Hb] ranges was not found to be statistically different despite a 40% increase in the in vitro viscosity from the anaemic to the polycythaemic state. The average individual correlation (based on five to seven measurements) between [Hb] at rest and after exercise and Vo2max was r= 0.89 (P > 0.01) in the former case and r= 0.92 (P > 0.01) in the latter. The running velocity corresponding to a blood lactate concentration of 4 mM (VHla4.0) increased from 15.3 ± 2.3 in the control state to 15.6±2.3 km h1 after the last transfusion (P > 0.01). A leftward shift of the blood lactate curve, expressed as a percentage of Vo2max, was found. In conclusion, the results obtained indicate a close relationship between Vo2max and [Hb] up to at least 170 g l-1. Furthermore, both inter-and intra-individual comparisons suggest that the influence of viscosity as such on Vo2max does not differ at high and low [Hb] levels.  相似文献   
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Objective

Eating disorders (ED) are an important and increasing problem in adolescents. The objective of this study was to examine the risk factors and the prevalence of risk for ED among male adolescent elite athletes and nonathletic controls. Differences between male athletes competing in aerobic, anaerobic and aerobic-anaerobic sports were examined as well.

Methods

This was a cross-sectional epidemiological study. A cross-sectional questionnaire survey and anthropometric measurements were conducted on 351 adolescents (athletes n = 228; controls n = 123). All participants were aged 15–17 at the time of measuring. Risk for ED was determined using a SCOFF questionnaire.

Results

The overall prevalence of the risk for ED in male adolescents was 24.8%, with no significant differences among athletes and controls or different subgroups of athletes (p>0.05), although the highest prevalence (37.2%) was registered in aerobic subgroup of athletes. Higher number of attempts to lose weight was associated with increased risk of ED in each group (athletes and controls). Other predictors referred to lack of breakfast and body composition in aerobic subgroup of athletes and number of meals and training frequency in anaerobic subgroup. The most common reasons for dieting were improvement of sport results (19.6–44.2%) and better self-esteem (41.5%) in athletes and controls respectively.

Conclusions

Participation in the competitive sport itself is not associated with the increased risk for ED. It seems that risk factors for ED for adolescent athletes competing in aerobic and anaerobic sports represent a subject that deserves consideration and further investigation in the future.  相似文献   
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Introduction

Developmental delay and dysmorphic features affect 1 – 3 % of paediatric population. In the last few years molecular cytogenetic high resolution techniques (comparative genomic hybridization arrays and single-nucleotide polymorphism arrays) have been proven to be a first-tier choice for clinical diagnostics of developmental delay and dysmorphic features.

Methods and results

In the present article we describe the clinical advantages of molecular cytogenetic approach (comparative genomic hybridization arrays and single nucleotide polymorphism arrays) in the diagnostic procedure of two children with developmental delay, dysmorphic features and additional morphological phenotypes. Additionally, we demonstrate the necessity of fluorescent in situ hybridization utilisation to identify the localisation and underlying mechanism of detected chromosomal rearrangement.

Conclusions

Two types of chromosomal abnormalities were identified and confirmed using different molecular genetic approaches. Comparative genomic hybridization arrays and single nucleotide polymorphism arrays are hereby presented as important methods to identify chromosomal imbalances in patients with developmental delay and dysmorphic features. We emphasize the importance of molecular genetic testing in patients’ parents for the demonstration of the origin and clinical importance of the aberrations prior determined in the patients. The results obtained using molecular cytogenetic high resolution techniques methods are the cornerstone for proper genetic counselling to the affected families.  相似文献   
349.

Introduction

Newborn screening in whole Slovenia started in 1979 with screening for phenylketonuria (PKU). Congenital hypothyroidism (CH) was added into the programme in 1981. The aim of this study was to analyse the data of neonatal screening in Slovenia from 1993 to 2012 for PKU, and from 1991 to 2012 for CH.

Methods

Blood samples were collected from the heels of newborns between the third and the fifth day after birth. Fluorometric method was used for screening for PKU, CH screening was done by dissociation-enhanced lanthanide fluorescent immunoassay (DELFIA).

Results

From 1993 to 2012, from 385,831 newborns 57 were identified with PKU. 184 newborns out of 427,396 screened from 1991 to 2012, were confirmed for CH. Incidences of PKU and CH in the periods stated are 1:6769 and 1:2323, respectively.

Conclusions

Successful implementation of newborn screening for PKU and CH has helped in preventing serious disabilities of the affected children. Adding screening for new metabolic diseases in the future would be beneficial.  相似文献   
350.

Background

The deficiency of SHOX gene (short stature homeobox-containing gene) has been recognized as the most frequent monogenetic cause of short stature. SHOX gene has been associated with short stature in Turner syndrome and Leri Weill dyschondrosteosis as well with non-syndromic idiopathic short stature. The aim of this study was to determine the frequency of SHOX deletions and mutations in a cohort of Slovenian children with short stature, and to delineate indications for routine SHOX gene mutation screening.

Methods and results

40 selected subjects with idiopathic short stature were screened for entire SHOX gene deletion and for mutations in the SHOX gene coding region (exon 2 to 6), together with sequences flanking the exon-intron boundaries. FISH analysis on metaphase and interphase spreads revealed no entire gene deletion. Additionally, no pathogenic point mutations or smaller deletion/duplications were identified in this study group.

Conclusions

SHOX gene deletions and point mutations are not a common cause of idiopathic short stature in a cohort of Slovenian children with short stature. Therefore, the frequency of SHOX mutations must be much lower as expected based on the reported data.  相似文献   
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