Adiponectin in human cord blood: relation to fetal birth weight and gender

Adiponectin is an adipocyte-derived plasma protein with insulin-sensitizing and antiatherosclerotic properties. The aim of this study was to examine whether adiponectin is present in human fetal blood, to define its association with fetal birth weight, and to evaluate whether dynamic changes in adiponectin levels occur during the early neonatal period. Cord blood adiponectin levels were extremely high (71.0 +/- 21.0 microg/ml; n = 51) compared with serum levels in children and adults and positively correlated with fetal birth weights (r = 0.4; P < 0.01). No significant differences in adiponectin levels were found between female and male neonates. In addition, there was no correlation between cord adiponectin levels and maternal body mass index, cord leptin, or insulin levels. Cord adiponectin levels were significantly higher compared with maternal levels at birth (61.1 +/- 19.0 vs. 17.6 +/- 4.9 microg/ml; P < 0.001; n = 17), and no correlation was found between cord and maternal adiponectin levels. There were no significant differences between adiponectin levels at birth and 4 d postpartum (61.1 +/- 19.0 vs. 63.8 +/- 22.0 microg/ml; n = 17). These findings indicate that adiponectin in cord blood is derived from fetal and not from placental or maternal tissues. The high adiponectin levels in newborns compared with adults may be due to lack of negative feedback on adiponectin production resulting from lack of adipocyte hypertrophy, low percentage of body fat, or a different distribution of fat depots in the newborns.     

Relationship between birth weight and blood pressure variability in children

This cross-sectional study investigates the relationship between birth weight, 24-h blood pressure and blood pressure variability in childhood. Blood pressure was measured in 976 schoolchildren, free from cardiovascular disease, aged between 6 and 16 years. Blood pressure variability was estimated as the standard deviation of the 24-h mean (systolic and diastolic) blood pressure values. Linear regression showed that variation in systolic or diastolic blood pressure was not significantly associated with birth weight. Similarly, no association was found between blood pressure variability and birth weight when using the birth weight groups used by a previous study. Adjusting for other covariates, including mean 24-h blood pressure, made little difference to the observed results. No interactions were observed between birth weight and either gender or age on blood pressure variability. The results of this study do not support the suggestion of a significant association between birth weight and blood pressure variation in childhood. This might suggest that blood pressure variability is influenced mainly by environmental or lifestyle factors, but as little research has been published in this area, further investigation is required and in particular it would be important to assess the use of other measures of blood pressure variation.     

Neonatal platelets from cord blood and peripheral blood

The haemostatic system in neonates is different from that of adults, possibly contributing to an increased incidence of bleeding disorders, such as intracranial hemorrhage. In this study, we analyzed platelets from cord blood and peripheral blood, collected at three time points after delivery from 20 term and 37 preterm neonates as well as blood from 20 healthy adults. Platelet membrane glycoproteins (GP) were quantified and P-selectin expression and PAC-1 binding ability before and after stimulation with TRAP were analyzed by whole blood flow cytometry. We found no significant differences in neonatal platelets from cord blood and peripheral blood within the first 24?h of life. Platelets from infants less than 30 weeks of gestation expressed lower levels of GP (33271?±?9381 vs. 44085?±?17287 for GPIIIa, P?<?0.05) and were less reactive than platelets from term newborns (4.3?±?3.3 vs. 20.1?±?11.8% PAC-1 positive platelets after stimulation with TRAP, P?<?0.05). A significantly lower level of GPIIb/IIIa expression on platelets from peripheral blood was seen in term newborns as well as preterm infants, compared to adults. There was only a partial enhancement in the degranulation ability (α-granules) (13.4?±?12.3 vs. 50.3?±?16.1% P-selectin positive platelets, P?<?0.05) and no significant increase for PAC-1 binding (13.6?±?10.9 vs. 15.3?±?5.9% PAC-1 positive platelets, P?=?0.8) during the first 12 days of life. In conclusion, we could demonstrate that neonatal platelet reactivity increases with gestational age.     

Neonatal platelets from cord blood and peripheral blood

The haemostatic system in neonates is different from that of adults, possibly contributing to an increased incidence of bleeding disorders, such as intracranial hemorrhage. In this study, we analyzed platelets from cord blood and peripheral blood, collected at three time points after delivery from 20 term and 37 preterm neonates as well as blood from 20 healthy adults. Platelet membrane glycoproteins (GP) were quantified and P-selectin expression and PAC-1 binding ability before and after stimulation with TRAP were analyzed by whole blood flow cytometry. We found no significant differences in neonatal platelets from cord blood and peripheral blood within the first 24h of life. Platelets from infants less than 30 weeks of gestation expressed lower levels of GP (33271+/-9381 vs. 44085+/-17287 for GPIIIa, P<0.05) and were less reactive than platelets from term newborns (4.3+/-3.3 vs. 20.1+/-11.8% PAC-1 positive platelets after stimulation with TRAP, P<0.05). A significantly lower level of GPIIb/IIIa expression on platelets from peripheral blood was seen in term newborns as well as preterm infants, compared to adults. There was only a partial enhancement in the degranulation ability (alpha-granules) (13.4+/-12.3 vs. 50.3+/-16.1% P-selectin positive platelets, P<0.05) and no significant increase for PAC-1 binding (13.6+/-10.9 vs. 15.3+/-5.9% PAC-1 positive platelets, P=0.8) during the first 12 days of life. In conclusion, we could demonstrate that neonatal platelet reactivity increases with gestational age.     

Low birth weight and blood pressure

Evidence supporting the association of normal and pathologically elevated blood pressure with low birth weight is presented and discussed in this article because of the overwhelming global prevalence of hypertension and its impact on individuals and nations. The findings provide strong impetus for the medical and public health communities to consider the concept of the "developmental origins of health and disease" in developing approaches to address the growing burden of hypertension worldwide.     

Effects of glutathione on red blood cell intracellular magnesium: relation to glucose metabolism.

Recent evidence suggests that the endogenous antioxidant glutathione may play a protective role in cardiovascular disease. To directly investigate the role of glutathione in the regulation of glucose metabolism in hypertension, we studied the acute effects of in vivo infusions of this antioxidant (alone or in combination with insulin) on whole body glucose disposal (WBGD) using euglycemic glucose clamp and the effects on total red blood cell intracellular magnesium (RBC-Mg) in hypertensive (n=20) and normotensive (n=30) subjects. The relationships among WBGD, circulating reduced/oxidized glutathione (GSH/GSSG) levels, and RBC-Mg in both groups were evaluated. The in vitro effects of glutathione (100 micromol/L) on RBC free cytosolic magnesium (Mg(i)) were also studied. In vivo infusions of glutathione (15 mg/minx120 minutes) increased RBC-Mg in both normotensives and hypertensives (1.99+/-0.02 to 2.13+/-0.03 mmol/L, P<0.01, and 1.69+/-0.03 to 1.81+/-0.03 mmol/L, P<0.01, respectively). In vitro GSH but not GSSG increased Mg(i) (179+/-3 to 214+/-5 micromol/L, P<0.01). In basal conditions, RBC-Mg values were related to GSH/GSSG ratios (r=0.84, P<0.0001), and WBGD was directly, significantly, and independently related to both GSH/GSSG ratios (r=0.79, P<0.0001) and RBC-Mg (r=0.89, P<0.0001). This was also true when hypertensive and control groups were analyzed separately. On multivariate analysis, basal RBC-Mg (t=6.81, P<0.001), GSH/GSSG (t=3. 67, P<0.02), and blood pressure (t=2.89, P<0.05) were each independent determinants of WBGD, with RBC-Mg explaining 31% of the variability of WBGD. These data demonstrate a direct action of glutathione both in vivo and in vitro to enhance intracellular magnesium and a clinical linkage between cellular magnesium, GSH/GSSG ratios, and tissue glucose metabolism.     

Somatomedin in cord blood: relationship to gestational age and birth size.

Somatomedin (SM) was determined by bioassay in cord blood from 100 neonates born at 24-42 weeks of gestation and from three infants with major congenital malformations. SM levels rose with gestational age and had a positive correlation with birth weight, length and head circumference independantly of gestational age. These findings suggest a relationship between somatomedin and fetal growth.     

Variant angina due to deficiency of intracellular magnesium

A 51-year-old man was diagnosed as having variant angina by documentation of typical ST elevation during anginal attack and also by showing coronary arterial spasm (#2 and #12) during hyperventilation on coronary arteriography. Large quantities of calcium blocking agents and nitrates could not improve his symptoms. Lack of intracellular magnesium was suspected from a daily excretion of urine magnesium (5.3 mEq) and magnesium tolerance test (56.7%). After hourly infusion of magnesium sulfate (80 mEq), coronary spasm could not be induced by ergonovine.     

Relationship between birth weight and awake blood pressure in children and adolescents in absence of intrauterine growth retardation

This study was designed to examine the relationship between birth weight (BW) and ambulatory blood pressure in children and adolescents, born at term in absence of intrauterine growth retardation.Twenty-four hour ambulatory blood pressure monitoring (ABPM) was performed on 332 children (150 boys), aged from 6 to 16 years. Subjects were stratified by BW textiles and age. ABPM was performed using SpaceLabs 90207 monitor during a regular school day. Blood pressure (BP) was measured every 20 min from 06:00 to 24:00, and thereafter every 30 min. Means of systolic BP (SBP) and diastolic BP (DBP) during 24 h, daytime (08:00 to 22:00), and nighttime (24:00 to 06:00) were calculated. Systolic and diastolic load was estimated as the percentage of measurements above the age- and sex-specific 95th percentile during the 24 h.BW was inversely related to daytime SBP (P = .04) and SBP load (P = .04) when controlled for sex, current height, ponderal index (weight/height³). and age. The predictive values of daytime SBP throughout the pediatric age group in the two extreme tertiles of BW (lowest, 2.500 to 3.200 kg and highest, 3.501 to 4.820 kg) were obtained from regression equations including SBP during activity period or SBP load and age. Children who had lower BW tended to have higher daytime SBP or SBP load at any age although this difference was not statistically significant. These differences became more evident as the subjects got older. BW is a determinant of daytime SBP even in the absence of intrauterine growth retardation. The influence of BW seems to increase with age.     

Response of blood platelets to resveratrol

The phytochemical resveratrol (3,4',5-trihydroxystilbene), which is found in grapes and wine, has been reported to have a variety of anti-inflammatory, anti-platelet and anti-carcinogenic effects. The aim of the present study was to evaluate the effects of trans-resveratrol on adhesion of blood platelets to collagen, as well as on thrombininduced platelet aggregation and malonyldialdehyde (MDA) production in vitro. Pretreatment of platelets with resveratrol (50 microg/ml) inhibited their adhesion to collagen (by 32% in resting platelets and by 57% in thrombin-activated platelets after 1 h of preincubation) and thrombin-induced platelet aggregation (by 59% after 30 min preincubation). Resveratrol also had an inhibitory effect on the generation of malonyldialdehyde (a marker of thromboxane A(2) synthesis) measured as thiobarbituric reactive substance in thrombin-activated platelets.     

The relationship between birth weight and blood pressure amplifies from childhood to adulthood.

OBJECTIVE: To investigate relationships between birth characteristics and blood pressure at age 20 years and to assess whether effects of birth weight on blood pressure are amplified from childhood to adulthood. DESIGN: A longitudinal study of 584 men and women from Adelaide, Australia, examined previously at 8 years and followed up at age 20 years. RESULTS: Birth weight was negatively associated with systolic pressure at age 20 years in men (regression coefficient 2.6 mmHg per kg; 95% confidence interval 0.7, 4.4) and women (regression coefficient 4.6 mmHg per kg; 95% confidence interval 2.9, 6.4), after adjustment for current weight There was an interaction with current size (P = 0.05 for men and P = 0.09 for women), such that effects were enhanced among individuals with relatively high weight or weight for height. Shortness at birth, thinness at birth, and low birth weight relative to placental weight were also associated with elevated systolic pressure at age 20 years. Effects of birth weight on blood pressure were stronger at age 20 than at age 8 years (P < 0.01 for men and P = 0.03 for women). This was not due simply to increased variability of blood pressure in adulthood. There were greater rises in blood pressure with age among individuals of relatively low birth weight. CONCLUSIONS: These findings are further evidence that poor fetal growth is associated with elevated blood pressure in later life. The results support the hypothesis that the relationship is amplified with increasing age.     

Relationship between size at birth and hypertension in a genetically homogeneous population of high birth weight

OBJECTIVE: To investigate the association between birth size and hypertension within a genetically homogeneous population of high birth weight. DESIGN: Cohort-study with retrospectively collected data on size at birth. SUBJECTS AND SETTING: The study included 4601 men and women born 1914-1935 in Reykjavik, Iceland, who participated in the Reykjavik Study of the Icelandic Heart Association. MAIN OUTCOME MEASURES: Birth size measurements, adult blood pressure (BP) and body mass index (BMI), and family history of hypertension. RESULTS: Birth weight was inversely related to hypertension in adulthood in women (P for trend < 0.001). The relationship was of borderline significance in men (P for trend = 0.051). A low ponderal index was significantly associated with high BP in women (P for trend = 0.025) but not men (P > 0.05). For women with an adult BMI > 26 kg/m2, the odds ratio for hypertension for those born weighing < 3.45 kg was 2.1 [95% confidence interval, 1.3-3.3, compared with women born weighing > 3.75 kg. The association was only significant in women without a family history of hypertension. CONCLUSIONS: An inverse association between size at birth and adult hypertension was seen in a population of greater birth size than has previously been investigated. The relation was strongest among women born small who were overweight in adulthood, and for those without a family history of hypertension. The results support the hypothesis that the association between birth weight and hypertension is not of genetic origin only. The large birth size of Icelanders might be protective and partly explain the lower mean systolic blood pressure in Iceland than in related nations.     

Estimation of glycated fetal hemoglobin in normal cord blood by isoelectric focusing. Correlation with maternal glycated hemoglobin and birth weight

Summary Glycated fractions of hemoglobin F and A (F₁, A_1c) were measured simultaneously in cord and maternal blood, respectively, in 109 normal women at delivery using an isoelectric focusing, method in polyacrylamide gel plates. Cord blood hemoglobin F₁ values (mean ± SD) were 5.92±1.09% and maternal blood hemoglobin A_1c values were 6.51±0.92%. The difference was statistically highly significant (p<0.001) and their values were also significantly correlated (p<0.001). Moreover, both values were also well correlated with those of maternal blood glucose (p<0.01), actual birth weight (p<0.01) and birth weight ratio (p<0.01). It is concluded that hemoglobin F₁ can be successfully separated and measured by isoelectric focusing. However HbF₁ estimation seems to have no obvious advantage against the maternal HbA_1c measurement as an index of fetal exposure to glucose during the last weeks of pregnancy. This work was supported by grants from the Ministry of Social Services, Athens, Greece; Alexander S. Onassis Foundation, Vaduz Liechenstein.     

新生儿出生方式对脐带血TSH的影响分析

目的　为进一步认识新生儿出生方式是脐带血 Ｔ Ｓ Ｈ 向高值偏移的重要影响因素。方法　调查沿海城市出生的新生儿 １ ０１４ 例，其中阴道产 ７６３ 例，剖宫产 ２５１ 例，采脐带血，使用免放分析（ Ｉ Ｒ Ｍ Ａ）检测 Ｔ Ｓ Ｈ。同期检测孕妇尿碘。结果　在孕妇尿碘中位数 ２１６．６４μｇ／ Ｌ 状况下，脐带血 Ｔ Ｓ Ｈ＞ ５ｍ Ｕ／ Ｌ 的频率，阴道产与剖宫产组分别为 ５６７％ 与 ２０３％ ，差异非常显著（χ２＝ １００．３８）。结论　首次揭示在孕妇碘营养明显改善后，新生儿在娩出过程中 Ｔ Ｓ Ｈ 的升高是一种普遍现象，以阴道娩出者最明显，是导致脐带血 Ｔ Ｓ Ｈ 向高值偏移的重要因素之一，并建议用剖宫产脐带血 Ｔ Ｓ Ｈ 值或足跟血 Ｔ Ｓ Ｈ 值校正阴道产脐带血 Ｔ Ｓ Ｈ 值。     

Adjustment for current weight and the relationship between birth weight and blood pressure in childhood

OBJECTIVE: To determine the role of current weight in mediating the relationship between birth weight and blood pressure within the context of the 'fetal origins' hypothesis. DESIGN: Prospective cohort study of 2507 pregnant women and their singleton offspring, delivered live at term, in Perth, Western Australia between 1989 and 1992. The study commenced at 16 weeks gestation with serial weight and blood pressure measurements recorded through early childhood. RESULTS: Inverse associations were found between birth weight and systolic blood pressure at ages 1, 3 and 6. The effect of birth weight on systolic blood pressure at age 6 reached statistical significance and was increased fourfold in magnitude to -2.3 mmHg [95% confidence interval = (-3.3 to -1.3), P < 0.01] after adjustment for current weight. The interaction term for birth weight and current weight was not statistically significant. Including intermediate weights did not produce a statistically significantly better model but did increase the magnitude of the estimated regression coefficient of birth weight on blood pressure, and only the birth weight and current weight terms were significant CONCLUSIONS: Adjustment for current weight serves to highlight the relationship between birth weight and blood pressure in childhood. Nevertheless, birth weight, rather than birth weight adjusted for current weight, is still the relevant predictor of later blood pressure within the context of the 'fetal origins' hypothesis.