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21.
Park  S; Harker  LA; Marzec  UM; Levin  EG 《Blood》1989,73(6):1421-1425
Fibrinolytic activity was found to be associated with sonicated platelet membranes after separation from cytosol by differential centrifugation. This fibrinolytic activity was attributed to the presence of a plasminogen activator, which was immunochemically identified as urinary-type plasminogen activator (uPA) by antibody neutralization assay, immunoblotting, and immunofluorescence. The molecular weight (mol wt) of this uPA was 54,000 and was present as the single chain form, although a small amount was detected in a higher mol wt complex indicative of a uPA-inhibitor complex. Treatment of membrane preparations with Triton X-100, 3 mol/L KCl, and 0.1 mol/L glycine, (pH 2.3), but not 10 mmol/L ethylenediamine tetraacetic acid (EDTA), removed the uPA from the membrane. This suggests that uPA is a peripheral membrane protein and that metal ions do not mediate protein- membrane association. Immunofluorescent staining revealed the presence of uPA on the outer surface of the platelet in preparations of intact unstimulated platelets. Thus, uPA is associated with the outer leaflet of the platelet membrane and may be involved with the acceleration of thrombus degradation observed with platelet-rich thrombi.  相似文献   
22.

Objective

To compare the pelvic floor function of primiparous women to women after a second delivery regarding symptoms of urinary and anal incontinence, anal sphincter ruptures and bladder-neck mobility.

Methods

A questionnaire evaluating symptoms of urinary and anal incontinence was used in nulliparous women before and 27 months after childbirth. Furthermore these symptoms were correlated with functional changes of the pelvic floor based on a careful gynecologic examination as well as perineal and endoanal ultrasound.

Results

112 nulliparous women were included, 49 women returned for follow-up on average 27 months (SD 4.4 months) after the first delivery. 39 women (group A) had just one delivery, 10 women (group B - 10/49) had had a second delivery. Apart from levator ani muscle strength, no significant difference between pelvic floor function of group A vs group B was demonstrable. Furthermore, we could show no significant difference for symptoms of urinary (11 (28.2%) vs. 5 (50.0%)) and anal incontinence (14 (35.9%) vs. 4 (40.0%)) between both groups. However, we found a lasting increase of stress urinary and anal incontinence as well as overactive bladder symptoms after one or more deliveries. The position of the bladder neck at rest was lower in both groups compared to the position before the first delivery and bladder neck mobility increased after one or more deliveries.

Discussion

Our study shows several statistically significant changes of the pelvic floor function even on average 27 months after delivery, but a subsequent delivery did not compromise the pelvic floor any further.  相似文献   
23.
OBJECTIVE—To determine the contribution of maternal glucose and lipids to intrauterine metabolic environment and fetal growth in pregnancies with gestational diabetes mellitus (GDM).RESEARCH DESIGN AND METHODS—In 150 pregnancies, serum triglycerides (TGs), cholesterol, free fatty acids (FFAs), glycerol, insulin, and glucose were determined in maternal serum and cord blood during the 3rd trimester. Maternal glucose values came from oral glucose tolerance testing and glucose profiles. Measurements of fetal abdominal circumference (AC) were performed simultaneously with maternal blood sampling and birth weight, and BMI and neonatal fat mass were obtained following delivery.RESULTS—Maternal TGs and FFAs correlated with fetal AC size (at 28 weeks: triglycerides, P = 0.001; FFAs, P = 0.02), and at delivery they correlated with all neonatal anthropometric measures (FFA: birth weight, P = 0.002; BMI, P = 0.001; fat mass, P = 0.01). After adjustment for confounding variables, maternal FFAs and TGs at delivery remained the only parameters independently related to newborns large for gestational age (LGA) (P = 0.008 and P = 0.04, respectively). Maternal FFA levels were higher in mothers with LGA newborns than in those with appropriate for gestational age (AGA) newborns (362.8 ± 101.7 vs. 252.4 ± 10.1, P = 0.002). Maternal levels of TGs, FFAs, and glycerol at delivery correlated with those in cord blood (P = 0.003, P = 0.004, and P = 0.005, respectively). Fetal triglyceride and cholesterol levels were negatively correlated with newborn birth weight (P = 0.001), BMI (P = 0.004), and fat mass (P = 0.001). TGs were significantly higher in small for gestational age (SGA) newborns compared with AGA or LGA newborns, while insulin-to-glucose ratio and FFAs were the highest in LGA newborns.CONCLUSIONS—In well-controlled GDM pregnancies, maternal lipids are strong predictors for fetal lipids and fetal growth. Infants with abnormal growth seem to be exposed to a distinct intrauterine environment compared with those with appropriate growth.There is strong evidential support for the “fetal origins” hypothesis, which connects adulthood hypertension, insulin resistance, and dyslipidemia to adverse intrauterine conditions during gestation that might be associated with disproportionate fetal growth. An increased risk for adult metabolic disorders is well documented for subjects born growth retarded (1). In addition, there are substantial data indicating that accelerated fetal growth predisposes to later obesity (2), especially in diabetic pregnancies (3). Therefore, normalization of fetal growth is a principle in the management of pregnancies with diabetes. Therapeutic strategies that focus on tight glucose control have often limited success in avoiding accelerated growth and may even result in growth restriction. In overweight pregnant women, fetal growth seems to be determined only to a small extent by maternal glucose values (4), and normalization of fetal growth may only be achieved by the addition of insulin therapy despite apparently good glucose control with diet (5).In view of increasing evidence that obesity, diabetes and cardiovascular diseases in later life may have prenatal antecedents, investigation of the determinants of intrauterine environment and fetal growth have become an important area of research. Variation of birth weight is strongly determined by neonatal fat mass, and it is likely that fetal growth disorders might also result from variations in maternal and fetal lipid metabolism. In nondiabetic pregnancies, maternal triglycerides (TGs) have been shown to be correlated with birth weight (69).Our study aimed to determine the potential relationship of maternal serum glucose and lipids to intrauterine metabolic environment and fetal growth during late pregnancy in well-controlled gestational diabetic women. Therefore, we investigated the correlation of maternal serum lipid and glucose parameters, measured at different time points in the 3rd trimester of pregnancy, with fetal and neonatal anthropometric parameters and with the correspondent parameters in cord blood representing the current intrauterine metabolic environment of newborns that are small (SGA), appropriate (AGA), and large for gestational age (LGA) from pregnancies complicated by gestational diabetes mellitus (GDM).  相似文献   
24.
OBJECTIVES: We sought to determine the types of congenital anomalies affecting infants of women with gestational diabetes mellitus or type 2 diabetes and to examine the relationship between those malformation types and measures of initial glycemia of women at entry into prenatal care with type 2 diabetes or at time of diagnosis in women with gestational diabetes mellitus. STUDY DESIGN: A total of 4,180 pregnancies complicated by gestational diabetes mellitus (n = 3764) or type 2 diabetes (n = 416) that were delivered after 20 weeks of gestation were reviewed for the presence of congenital malformations diagnosed before hospital discharge. Anomalies were categorized as being absent, minor, major, genetic syndromes, or aneuploidies. Major anomalies were further categorized by the number and type of affected organ systems. In addition to maternal clinical and historical parameters, the initial fasting serum glucose either from the diagnostic glucose tolerance test (gestational diabetes mellitus) or at entry to prenatal care (type 2 diabetes) and the initial glycosylated hemoglobin before insulin therapy were examined for a relationship to anomalies. RESULTS: The initial fasting serum glucose and glycosylated hemoglobin levels were significantly higher in pregnancies with major (n = 143) and minor (n = 112) anomalies and genetic syndromes (n = 9) compared with pregnancies with no anomalies (n = 3895). Of those pregnancies with major anomalies, the most commonly affected organ systems were the cardiac (37.6%), musculoskeletal (14.7%), and central nervous systems (9.8%) and anomalies involving multiple organ systems (16%). There was no increased predominance of any specific organ system involvement seen with increasing fasting serum glucose levels in pregnancies with major congenital anomalies. Pregnancies with major anomalies affecting multiple organ systems had significantly higher initial fasting serum glucose levels (166 +/- 64 mg/dL) compared with pregnancies in which one organ system was affected (141 +/- 55 mg/dL, P <.04) or no organ systems were affected (115 +/- 38 mg/dL, P <.0001). CONCLUSION: Congenital anomalies in offspring of women with gestational and type 2 diabetes affect the same organ systems that have been previously described in pregnancies complicated by type 1 diabetes. Increasing hyperglycemia at diagnosis or presentation for care was associated with an increasing risk of anomalies in general and with anomalies involving multiple organ systems without a preferential increase in involvement of specific organ system.  相似文献   
25.
OBJECTIVE: The purpose of this study was to identify which maternal, antepartum, or neonatal clinical parameters were predictive for a high risk of diabetes mellitus in the puerperium in women with recent gestational diabetes mellitus and to calculate the associated diabetes mellitus rates and odds ratios. STUDY DESIGN: One thousand six hundred thirty-six women underwent an oral glucose tolerance test within 1 to 4 months of delivery. Demographic, historic, and antenatal glycemic parameters and neonatal outcome parameters were tested by univariate and multivariate logistic regression for risk of postpartum diabetes mellitus. Continuous variables were divided into quartiles that compared the upper to lower quartile adjusted odds ratio and prevalence of diabetes mellitus. RESULTS: Postpartum diabetes mellitus was diagnosed in 230 women (14.1%) according to the American Diabetes Association criteria (1997). No maternal demographic or neonatal parameters were significantly associated with diabetes mellitus. The final model of independent predictors in decreasing significance included the highest fasting plasma glucose level during pregnancy, any fasting plasma glucose level of > or = 105 mg/dL (class A(2)), the area under the curve of pregnancy oral glucose tolerance test, gestational age at diagnosis, previous gestational diabetes mellitus history, and 50-g glucose challenge test results. The fasting plasma glucose level was the best discriminator, with a 21-fold (95% CI, 4.6-96.3) increased odds ratio comparing the 4th quartile (fasting plasma glucose level, >121 mg/dL; diabetes mellitus rate, 36.7%) to 1st quartile (fasting plasma glucose level, < 95 mg/dL; diabetes mellitus rate, 0.5%). The presence of previous gestational diabetes mellitus or current class A(2) gestational diabetes mellitus approximately doubled the odds ratio for diabetes mellitus. The odds ratio increased 3- to 4-fold when the area under the curve was > or = 33.36 min small middle dot g/dL (4th quartile) or the glucose challenge test was > or = 155 mg/dL (2nd-4th quartiles) and decreased > 50% if gestational diabetes mellitus was diagnosed at > 27 weeks (3rd-4th quartile). CONCLUSION: During pregnancy, the highest fasting glucose level, followed by the severity of glucose intolerance, and earlier gestational diabetes mellitus diagnosis were the best predictors for postpartum diabetes mellitus. Diabetic education should begin during pregnancy, especially for women who are identified to be at a high risk when they are highly motivated and under medical care.  相似文献   
26.
OBJECTIVE: The purpose of this study was to investigate the rate of hypoglycemia in large-for-gestational-age infants of nondiabetic mothers in relation to maternal or neonatal risk factors. STUDY DESIGN: Hospital charts of all term large-for-gestational-age infants born between 1994 and 1998 (n = 1136) were analyzed for the rate of neonatal hypoglycemia (capillary glucose level, < or =30 mg/dL) during the first 24 hours of life. Infants of women with preexisting or gestational diabetes mellitus were excluded (n = 180). Neonatal glucose testing was performed at 1 or 2 hours of life, with subsequent measurements every 4 to 6 hours. Maternal and neonatal parameters were compared between neonates with and without hypoglycemia, including recent oral glucose tolerance test values in those women who were tested (n = 358). RESULTS: Of 956 infants, 69 infants (7.2%) were not tested for hypoglycemia. In the remaining 887 infants, hypoglycemia occurred in 142 infants (16%) within the first 24 hours of life. The incidence of hypoglycemia decreased sharply during the first few hours of life, from 9.2% within the first hour of life, to 3.5% between 2 to 5 hours (cumulative) of life, and 2.4% between 6 and 24 hours of life. Gestational age at delivery was the only neonatal parameter that differed significantly between infants with and without hypoglycemia (39.5 vs 39.3 weeks, P =.01). The antenatal 1-hour oral glucose tolerance test value was the only predictive maternal parameter (141.5 vs 163.0 mg/dL, P <.006). There was an incremental risk of hypoglycemia with increasing 1-hour oral glucose tolerance test values, with hypoglycemia rates of 2.5%, 9.3%, 22.0%, and 50.0% that were associated with maternal 1-hour glucose values of <120, 120-179, 180-239, and > or =240 mg/dL, respectively (P <.05, for all comparisons). CONCLUSION: Routine glucose testing is indicated in large-for-gestational-age newborn infants of nondiabetic mothers. The 1-hour glucose value of the maternal oral glucose tolerance test is a fairly good predictor of subsequent neonatal hypoglycemia. A single elevated 1-hour value of > or =180 mg/dL markedly increases the risk of neonatal hypoglycemia.  相似文献   
27.

OBJECTIVE

Serial measurements of the fetal abdominal circumference have been used to guide metabolic management of pregnancies complicated by gestational diabetes mellitus (GDM). A reduction in the number of repeat ultrasound examinations would save resources. Our purpose was to determine the number of serial abdominal circumference measurements per patient necessary to reliably predict the absence of fetal overgrowth.

RESEARCH DESIGN AND METHODS

Women who had GDM were asked to return for repeat ultrasound at 3- to 4-week intervals starting at initiation of care (mean 26.9 ± 5.7 weeks). Maternal risk factors associated with fetal overgrowth were determined.

RESULTS

A total of 4,478 ultrasound examinations were performed on 1,914 subjects (2.3 ± 1.2 per pregnancy). Of the 518 women with fetal abdominal circumference >90th percentile, it was diagnosed in 73.9% with the first ultrasound examination at entry and in 13.1% with the second ultrasound examination. Of the fetuses, 85.9 and 86.9% of the fetuses were born non-large for gestational age (LGA) when abdominal circumference was <90th percentile at 24–27 weeks and 28–32 weeks, respectively, and 88.0% were born non-LGA when both scans showed normal growth. For those women who had no risk factors for fetal overgrowth (risk factors: BMI >30 kg/m2, history of macrosomia, and fasting glucose > 100 mg/dl), the accuracy of prediction of a non-LGA neonate was 90.0, 89.5, and 95.2%. The predictive ability did not increase with more than two normal scans.

CONCLUSIONS

The yield of sonographic diagnosis of a large fetus drops markedly after the finding of a fetal abdominal circumference <90th percentile on two sonograms, which excludes with high reliability the risk of a LGA newborn. The ability was enhanced in women who had no risk factors for neonatal macrosomia.The recommendations for diagnosis and treatment of gestational diabetes mellitus (GDM) of the Fifth International Workshop-Conference on Gestational Diabetes Mellitus (1) suggest consideration of fetal growth patterns to guide metabolic management of pregnant women with GDM. Estimation of fetal weight, particularly at term and in fetuses with high neonatal weight, is not as precise as is desirable (2). However, enlarged size (36) and accelerated growth velocity of the fetal abdominal circumference in the third trimester is known to predict large-for-gestational-age (LGA) birth weight (7). Previous randomized studies have demonstrated that measurement of the fetal abdominal circumference throughout pregnancy in women who have GDM is useful to identify pregnancies at high risk for fetal overgrowth and therefore in need of intensified intervention (811). On the other side, relaxed glycemic goals had been allowed in women with sonographic evidence of normal fetal growth. Besides saving insulin therapy, this approach reduced the rate of fetal growth restriction in the fetuses of those women. Published protocols for fetal growth–based management require sonographic determination of fetal abdominal circumference at the time of diagnosis of GDM (811) followed by repeat examinations at 2 (11)- to 4-week intervals (9,10). Serial sonographic examinations are costly and require the time and expertise of experienced ultrasonographers and/or physicians.The purpose of our study was to determine the number of sequential ultrasound examinations necessary not to miss development of an enlarged abdominal circumference during pregnancy and to assure a low risk for a LGA neonate with a great degree of certainty when the scans suggest normal fetal growth. In addition, we wished to evaluate whether the absence of maternal risk factors for neonatal macrosomia would enhance the accuracy of the ultrasound examination predicting a non-LGA neonate.  相似文献   
28.

OBJECTIVE

To determine the concentrations of adipocyte fatty acid–binding protein (AFABP) and other adipocytokines in maternal and cord serum of pregnant women with gestational diabetes mellitus (GDM) and of control subjects and to relate them to indexes of insulin sensitivity.

RESEARCH DESIGN AND METHODS

In 86 control and 98 GDM pregnant women, venous blood was collected before vaginal delivery and arterial blood from cord immediately after delivery. Serum insulin and adipocytokines were measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

GDM women had higher prepregnancy BMI, and data were adjusted for it. Maternal serum insulin, insulin-to-glucose ratio, homeostasis model assessment (HOMA), AFABP, and retinol-binding protein 4 (RBP4) were higher and adiponectin was lower in GDM than in control subjects, whereas serum glucose, insulin, insulin-to-glucose ratio, HOMA, nonesterified fatty acids, and RBP4 were higher and glycerol, AFABP, and adiponectin were lower in cord blood serum of GDM than of control subjects. AFABP and adiponectin in cord serum of control subjects were higher than in maternal serum; in GDM women no difference was found for AFABP in cord versus maternal serum, although adiponectin remained higher in cord. Values of leptin in both groups were lower in cord than in maternal serum, and those of RBP4 were lower in only GDM women.

CONCLUSIONS

It is suggested that fetal tissues are the main source of cord arterial serum AFABP, and in GDM fetuses AFABP values correlate with adiposity markers. A downregulation of adiponectin and upregulation of RBP4 in GDM mothers and their fetuses may be related to their insulin-resistant condition, whereas changes in AFABP do not seem to be related.Pregnancy is associated with substantial changes in maternal metabolism, which provide sufficient energy and nutrients to the fetus. Glucose is the primary source of energy for the fetoplacental tissues but, because the fetus only produces glucose under extreme conditions, it is necessary to ensure its transport through the placenta. In this context, the mother develops a state of insulin resistance during midpregnancy and progressing through the third trimester, which reduces the consumption of glucose by maternal tissues and increases gluconeogenesis enabling a sufficient supply of glucose to the fetus (1). This causes a positive maternal-fetal glucose gradient, which facilitates its placental transfer. However, in a substantial proportion of pregnancies, the insulin-resistant condition is greatly increased and gestational diabetes mellitus (GDM) develops (2); the consequent adverse metabolic state results in complications for the mother, the fetus, and the neonate (3).The mechanisms responsible for the development of GDM are unclear, but mechanisms similar to those in type 2 diabetes have been implicated (4), supporting the notion that the two conditions have similar underlying pathophysiology. Adipose tissue secretes several specific proteins called adipocytokines that modulate the action of insulin in different tissues (5), suggesting that alterations in the expression and secretion of these factors may be linked to GDM and related diseases. Recently, adipocyte fatty acid–binding protein (AFABP), a member of the mammalian intracellular fatty acid–binding protein multigene family (6), was described as a novel adipocytokine. This protein is responsible for intracellular fatty acid trafficking and contributes to the regulation of hormone-sensitive lipase activity (7). Moreover, mice deficient in AFABP are protected from development of hyperinsulinemia, hyperglycemia, and insulin resistance (8,9). Recent studies have shown that AFABP is present in human serum (10), and its levels are associated with insulin resistance and type 2 diabetes (10,11). Therefore, in adults, AFABP concentrations have been considered an independent predictor of diabetes, contributing to the control of systemic insulin sensitivity and of lipid and glucose metabolism. So far there is only one study where the level of AFABP in GDM women at midpregnancy has been determined (12), and no information is available on its levels either during late pregnancy or in cord serum. Thus, the objectives of the current study were to measure the concentrations of AFABP in maternal and cord serum of control and GDM pregnant women and to examine its relationship with glycemia and other related variables.  相似文献   
29.
30.
The haemodynamic effects of nipradilol, a new non-selective β-adrenoreceptor blocker with vasodilating actions like nitroglycerin, were examined in rats with portal hypertension due to portal vein stenosis. Portal hypertensive rats were divided into five groups receiving infusion of placebo, 3 mg of propranolol, 300, 600 and 1200 μg of nipradilol. At its highest dose, nipradilol achieved a reduction of 34.4 ± 4.4% in heart rate which was similar to that in the propranolol group (36.5 ± 2.4%). Also for other systemic haemodynamic parameters, the nipradilol 1200 μg group exhibited changes not significantly different from those in the propranolol group; mean arterial pressure (- 13 vs - 14%), cardiac index (- 37 vs - 31%) and systemic vascular resistance (+ 29 vs+ 32%). In contrast to the similar changes in the systemic circulation, a 1200 μg dose of nipradilol lowered portal pressure significantly more than propranolol (- 4.3 ± 0.6 vs - 2.9 ± 0.2 mmHg, P≤ 0.05). Nipradilol then reduced portal blood flow by 22% (P≤ 0.05) without a significant change in portocollateral resistance. On the other hand, propranolol not only caused a reduction in portal blood flow of 30% (P≤ 0.01), but also an increase in portocollateral resistance of 21% (P≤ 0.05). The results suggest that nipradilol may ensure a more effective control of portal hypertension than propranolol, presumably via its venodilatory action on portocollateral vessels.  相似文献   
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