Maternal and fetal plasma vitamin E to total lipid ratio and fetal RBC antioxidant function during gestational development.

Placental transfer of vitamin E was investigated from 19 to 35 weeks of gestation by analysis of fetal and maternal blood samples for total tocopherol, total lipids, and fetal red blood cell antioxidant reserves. Fifty-two fetal blood samples were obtained under ultrasonographic guide by percutaneous umbilical blood sampling. Thirteen were from fetuses with gestational age less than or equal to 22 weeks (x serum vitamin E = 0.4 +/? 0.14 mg/dl), 12 were from fetuses at 23-27 weeks gestation (x serum vitamin E = 0.4 +/? 0.21 mg/dl), and 27 were from fetuses with gestational age 28-38 weeks (x serum level = 0.37 +/? 0.18). Total lipid levels ranged from 140 to 216 mg/dl. Maternal plasma vitamin E concentrations correlated significantly with concurrent values in the fetus. There were no significant differences in serum vitamin E levels or vitamin E to total lipid ratio in samples from early, mid, or late gestation in either the mother or fetus. Red blood cell antioxidant reserve on samples from 18 fetuses were grossly abnormal by three different functional assays. On the basis of these data, placental transfer of vitamin E appears to be relatively constant through advancing gestation. Red blood cell antioxidant reserve is uniformly low.     

Developmental changes in pulmonary and renal angiotensin-converting enzyme concentration in fetal and neonatal horses

Angiotensin-converting enzyme (ACE) has an active role in the control of blood pressure and body fluid homeostasis both before and after birth. This study investigated the ontogeny of pulmonary and renal ACE concentrations in fetal and neonatal horses. Fetal pulmonary ACE concentration increased from 250 days towards term (c. 335 days). Newborn foals showed significantly higher mean concentrations of pulmonary ACE (4.40 +/- 0.62 nmol min(-1) mg protein(-1)) than both fetuses during late gestation (1.23 +/- 0.51 nmol min(-1) mg protein(-1)) and animals aged 1 day to 2 weeks of postnatal age (0.85 +/- 0.15 nmol min(-1) mg protein(-1)). Renal ACE was detected in fetal horses from 100 days of gestation but showed no developmental trend during the second half of gestation or in early postnatal life. Overall in the fetus, mean concentrations of renal ACE were also approximately 10 times lower than mean pulmonary values. Renal ACE concentration may be related to the functional immaturity of the equine kidneys. The increase in pulmonary ACE concentration seen towards term in the fetal horse may be induced by the prepartum cortisol surge that occurs very close to delivery in this species. Therefore, premature delivery in this species may interrupt the onset of ACE production in the fetal lungs and circumvent the normal maturation of the renin-angiotensin system.     

孕20～28周胎儿鼻前皮肤正常值范围的建立

目的：建立中国南方人群孕20～28周胎儿鼻前皮肤（ PT）厚度的正常值范围。方法2013年7月至2014年12月,对参加广州市妇女儿童医疗中心中孕期（孕20～28周）超声结构筛查的胎儿进行PT测量,产后3个月进行随访,剔除胎儿结构异常,妊娠合并症及胎儿出生后明显结构缺陷的病例,建立孕20～28周胎儿PT值正常值曲线模型。结果在440例正常胎儿病例中,孕妇中位年龄28岁（21～42岁）,中位孕周23周（20～28周）,胎儿PT中位值4．0mm（2．9～7．2mm）。随着孕周增加, PT从20周的3．8mm增加到孕28周的5．4mm。统计分析,胎儿PT值与孕周呈线性正相关,线性回归方程：PT＝0．285＋0．17× GA（R2＝0．194,P＝0．000）。结论孕20～28周,胎儿PT随孕周增加而增加,并与孕周呈直线相关。     

Vitam A deficiency and fetal growth and development in the rat.

Studies were conducted to examine in detail the effects of vitamin A deficiency on fetal growth and development in the rat. The gradations of deficiency were examined in two studies. The first included total vitamin A depletion followed by retinoic acid supplements, and the second included three different levels of restricted intake of retinyl acetate (42, 16, or 8 mug of retinol equivalents/day/kg of body weight) in vitamin A-depleted rats. In the first study, extensive fetal resorption and death were observed in retinoic acid-fed females after day 14 of gestation. These findings confirmed the morphological studies of Thompson and associates (Proc. Roy. Soc. London, Ser. B 159, 510-535, 1964) who found the earliest Detectable histological lesions to be in the placentas at days 15-16 of pregnancy. Analyses were carried out of the total weight, the DNA, RNA, and protein contents of fetuses and placentas of different gestational ages in retinyl ester-fed and retinoic acid-fed females. Biochemical changes indicative of a reduced rate of cell division were observed in both fetus and placenta by day 14 in the retinoic acid-fed rats. The few live fetuses in this group maintained a growth rate of only 60-70% of that of the fetuses of retinyl ester-fed dams after day 14. By contrast, the growth rate of the placentas (of live fetuses) after day 14 of gestation was not as consistently affected by retinol deficiency. Restriction of retinyl acetate intake (in the second study) significantly reduced both the total litter size and the number of live pups per litter. Most of the females in the retinyl acetate-restricted groups delivered pups that had normal body weight and appeared normal on visual inspection. Significant differences from normal controls were seen only in the neonates from dams given 8 mug of retinol equivalents (per kg of body weight per day), which had smaller livers and kidneys than the control neonates. In contrast, the weights of the brains of the neonates in all three retinyl acetate-restricted groups showed no differences from control values. Vitamin A assays on maternal and neonatal sera and livers indicated that the transport of vitamin A across the placenta was well regulated, and suggested that this transport is maintained with high priority in the presence of maternal deficiency. The effects of vitamin A deficiency on fetal growth and development might reflect primary effects on the placenta, with secondary effects on the fetus, or primary direct effects on the fetus itself. The mechanisms of the observed effects remain to be explained.     

Vitamin E and selenium in preterm infants: lack of effect on clinical patency of ductus arteriosus

Levels of antioxidant defenses, which include vitamin E and Se-dependent GSH-Px, are generally relatively low in the fetus and neonate. Se-dependent GSH-Px and vitamin E are known to modulate biosynthesis of eicosanoids and therefore could have the potential for affecting patency or closure of the ductus arteriosus after birth. We evaluated some indices of antioxidant defense in sick LBW infants in relationship to one another as well as to clinical PDA, and investigated the effects of producing a rapid rise in serum vitamin E levels in some of these infants. Twenty-nine sick preterm infants (B. W. 750-1750 g) were randomized into control and vitamin E supplemented groups; the latter received dl-alpha-tocopherol IM., commencing within 12 hours of birth, to a total dosage of 175 mg/kg over four weeks. Most E-supplemented infants attained serum tocopherol levels greater than 0.50 mg/dl (12 mumol/l) within 24 hours of the first dose. Vitamin E supplementation did not influence clinical patency or closure of the ductus arteriosus, and no correlation could be established between serum levels of alpha-tocopherol, Se, GSH-Px or NPS and PDA. At 4 weeks vitamin E-supplemented infants had serum levels of the other antioxidant indices that were not significantly different from the non-supplemented babies.     

Parallel changes between the percentage of fetal pituitary cells immunoreactive to oestrogen receptor alpha and the concentration of 17beta-oestradiol in fetal and maternal plasma during gestation in sheep

The present study was designed to investigate the relationship between fetal sheep pituitary oestrogen receptor (ER) alpha expression and changes in fetal and maternal plasma 17beta-oestradiol (E2) concentrations during gestation. The results revealed that immunoreactivity for ER was located in the nuclei and distributed throughout the fetal pituitary gland during gestation. The percentage of ERalpha-positive cells was approximately 2% of the total cell population in female fetuses at Day 60 of gestation, increased to approximately 7% and 13% of the total cell population at Days 90 and 120 of gestation, respectively, and then declined to approximately 10% at birth. The fetal plasma E2 concentrations were approximately 19 and 71 pg mL(-1) at Days 90 and 120 of gestation, respectively, and decreased to 22 pg mL(-1) after birth. In male fetuses, plasma E2 concentrations and the percentage of ERalpha-positive cells were similar to values in female fetuses throughout gestation, except on Day 120 when the plasma E2 level in female fetuses was significantly higher than in male fetuses. These data demonstrate that changes in the percentage of fetal pituitary ERalpha-positive cells parallel fetal plasma E2 concentrations throughout gestation.     

Effects of different sampling points on evaluation of fetal descending aortic flow

BACKGROUND: Widespread use of fetal aortic blood flow velocity measurements for assessment of fetal circulatory status has been precluded by difficulties in achieving an adequate Doppler insonation angle at particular sampling points. The goal of this study was to evaluate the differences in resistance index (RI) and systolic peak velocity (Vmax) of fetal aortic blood flow velocity waveforms throughout gestation among various Doppler sampling points. METHODS: A total of 551 normal women between 18-41 weeks of pregnancy participated in this study. Pulsed Doppler flow velocity waveforms were acquired from three different aortic sampling points (thoracic portion, beneath the diaphragm, and abdominal portion) of the fetal descending aorta. The Vmax and RI were calculated at the respective sampling points. RESULTS: The Vmax were significantly lower in abdominal portion than those in thoracic portion at every time point (from 69 +/- 11 cm/second in thoracic to 49 +/- 8 cm/second in abdominal portion at 18-19 gestational weeks, p<0.0001), and RI were also lower (from 0.84 +/- 0.05 in thoracic portion to 0.76 +/- 0.05 in abdominal portion at 18-19 gestational weeks, p<0.0001). Significant increase in the Vmax was seen until third trimester (from 58+/-10 cm/second at 18-19 gestational weeks to 113 +/- 13 cm/second at 38-39 gestational weeks beneath the diaphragm, p<0.0001), while the RI remained stable (0.79 +/- 0.04 at 18-19 gestational weeks; 0.80 +/- 0.05 at 38-39 gestational weeks beneath the diaphragm). CONCLUSIONS: In measuring the fetal circulatory status, these data demonstrate that the sampling point should be considered when evaluating the maximum systolic velocity and the resistance index of the fetal descending aorta.     

Antioxidant supplementation enhances neutrophil oxidative burst in trained runners following prolonged exercise

The influence of an antioxidant vitamin supplement on immune cell response to prolonged exercise was determined using a randomized, double-blind, placebo-controlled, cross-over study. Twelve healthy endurance subjects (n = 6 male, n = 6 female; mean +/- SD for age, 30.1 +/- 6.2 yr; height, 1.76 +/- 7 m; body mass, 72.2 +/- 10.2 kg; VO2max, 63.7 +/- 12 ml x kg(-1) x min(-1)) participated in the study. Following a 3-week period during which subjects ingested a multivitamin and -mineral complex sufficient to meet the recommended daily allowance, they took either a placebo or an antioxidant vitamin supplement (containing 18 mg beta-carotene, 900 mg vitamin C, and 90 mg vitamin E) for 7 days prior to a 2-h treadmill run at 65% VO2max. Blood samples were drawn prior to and immediately following exercise. These were analyzed for neutrophil oxidative burst activity, cortisol and glucose concentrations, and white blood cell counts, as well as serum anti-oxidant vitamin concentrations. Plasma vitamin C, vitamin E, and beta-carotene concentrations significantly increased following 7-day supplementation (p < .05). In comparison to the placebo group, neutrophil oxidative burst was significantly higher following exercise (p < .05), but no differences were found in any other parameter following the 7-day supplementation period. Although the impact of exercise on neutrophil function is multifactorial, our data suggest that antioxidant supplementation may be of benefit to endurance athletes for the maintenance of this particular function of the innate immune system following the 7-day supplementation period.     

Serum and liver concentrations of vitamin A in Thai fetuses as a function of gestational age.

Serum and liver vitamin A values were determined in 26 male and 20 female Thai fetuses varying in gestational age from 13 weeks to term. In general pregnancies were of healthy young women from the Bangkok area. The median, mean and range of fetal serum retinol values (+/- SE) were 25.8, 30.7 +/- 3.0, and 1.9 to 109.6 microgram/100 ml, and of liver values were 16.4, 19.4 +/- 2.2, and 1.1 to 51.6 microgram retinol per gram of liver. Median and mean serum and liver values were about 10% higher in males than in females, but not significantly so. Serum retinol concentrations neither correlated with liver concentrations, except below 5 microgram/g, nor served as a valid indicator of total liver stores of vitamin A. Serum retinol values declined slowly with gestational age to term, whereas liver vitamin A concentrations tended to increase until the 28th week and then to fall until term. Whereas the liver to body weight ratio remained essentially constant (0.0425 +/- 0.003, P less than 0.0001) during the gestational period, vitamin A concentrations in both serum and liver showed marked variability.     

Plasma tocopherol and tocopherol to lipid ratios in a normal population of infants and children

The plasma tocopherol concentrations were measured by HPLC in 73 apparently healthy West German children aged from 1 to 14 years and in 7 cord blood samples and 5 infants below 1 year of age. Total tocopherols ranged from 584 to 2024 micrograms/dl in the children above 1 year of age (mean 1046 +/- 283 micrograms/dl) and from 511 to 1155 micrograms/dl in the infants below 1 year of age (mean 879 +/- 270 micrograms/dl). The total tocopherol/total lipid ratio-representing the reliable index for vitamin E status-was far above 0.6 mg/g lipid, a level which is regarded as the lower limit of normal (range 1.23 to 4.09 mg/g total lipid in the older children and 1.52 to 2.05 in the infants below 1 year). A positive correlation was found between plasma lipids and total tocopherol (r = 0.71). Our investigation demonstrated an excellent vitamin E status in the children investigated which is considered to reflect the high supply of West German food with PUFA and vitamin E.     

Risk factors for cardiovascular disease and diabetes in two groups of Hispanic Americans with differing dietary habits

OBJECTIVE: The purpose of this study was to determine if Hispanic Seventh-Day Adventists (SDAs), who typically eat a diet lower in fat, saturated fat and protein, and higher in complex carbohydrates and dietary fiber than the usual omnivorous diet, exhibit lower risk factors for cardiovascular disease (CVD) and Type 2 diabetes compared to Hispanic Catholic omnivores. METHODS: Anthropometric characteristics, dietary intake, blood pressure, serum lipids, glucose and insulin, as well as plasma ascorbic acid and vitamin E concentrations, were measured in two groups of Hispanic study participants residing in Denver, Colorado: 74 SDA study participants (x age: 42+/-1.5 y) and 45 Catholic participants (x age: 44+/-2.2 y). RESULTS: The SDAs reported lower dietary intakes of total fat, saturated fat and cholesterol and higher relative intakes of carbohydrate and dietary fiber compared to their Catholic counterparts. The SDAs exhibited significantly lower body mass index (BMI = 27.2+/-0.6) and waist-to-hip ratios (WHR = 0.84+/-0.01) compared to the Catholics (BMI = 31.4+/-1.1; WHR = 0.88+/-0.01). The SDAs, compared to the Catholics, had lower fasting insulin (11.4+/-0.6 vs. 18.9+/-3.1 microu/ml) and glucose concentrations (88.6+/-1.1 vs. 104.1+/-5.4 mg/dl). The SDA Hispanics, compared to the Catholic Hispanics, exhibited significantly lower values for systolic blood pressure (SBP = 1102 vs. 118+/-3 mm Hg), serum total cholesterol (STC = 198+/-5 vs. 214+/-6 mg/dl) and serum triglycerides (TG = 152+/-12 vs. 232+/-27) and higher serum concentrations of high-density lipoprotein cholesterol (HDL-C = 44.7+/-1.3 vs. 39.1+/-1.4 mg/dl) and ascorbic acid (1.14+/-0.08 vs. 0.87+/-0.07 mg/dl). Low-density lipoprotein cholesterol (LDL-C) and vitamin E concentrations were not significantly different between groups, but the SDAs exhibited lower ratios of STC/HDL-C and LDL-C/HDL-C. CONCLUSION: Hispanic American SDAs, who eat a plant-based diet, exhibit a more favorable blood lipid profile, lower blood pressure and lower risk for Type 2 diabetes compared to Hispanic American Catholics, who do not eat a plant-based diet.     

Maternal and fetal vitamin E concentrations and selenium-vitamin E interrelationships in dairy cattle

Paired dam-fetus liver and serum samples were collected from 101 pregnant dairy cattle at slaughter to determine mean fetal and maternal liver and serum vitamin E concentrations, relationships between maternal and fetal vitamin E status and interrelationships between selenium and vitamin E status. Fetal age was estimated from fetal crown-to-rump length. Fetal alpha-tocopherol concentration ranged from 0 to 31.4 micrograms/g dry wt with a mean of 7.1 micrograms/g dry wt and from 0 to 0.92 micrograms/ml with a mean of 0.29 micrograms/ml for liver and serum, respectively. Mean maternal liver (12.5 micrograms/g dry wt) and serum (2.16 micrograms/ml) alpha-tocopherol concentrations and vitamin E to cholesterol ratio (1.45) were 1.8, 7.4 and 3.5 times greater (P less than 0.0001) than fetal means, indicating limited placental transfer of vitamin E to the fetus. Gestational age had no effect on maternal vitamin E concentration, however, fetal tissue alpha-tocopherol concentration declined (P less than 0.05) with fetal age. Maternal serum alpha-tocopherol concentration and fetal age were found to best predict fetal alpha-tocopherol concentration in serum. Interrelationships between selenium and vitamin E status were minimal. These data suggest inefficient placental transfer of vitamin E, resulting in minimal protection of the neonate from vitamin E-deficiency disease as a result of prepartal maternal supplementation.     

Plasma-Saturating intakes of vitamin C confer maximal antioxidant protection to plasma.

OBJECTIVE: Supplemental vitamin C has been shown to reduce oxidative damage in vivo, yet the dose-response relationship between vitamin C intake and antioxidant protection is not known. This report examined blood indicators of oxidative stress in subjects consuming graded doses of vitamin C, from 75 to 2,000 mg/day. METHODS: Ten healthy, non-smoking men and women (26.1 +/- 2.1 years) were recruited from a campus population. During the ten-week study, subjects limited fruit and vegetable consumption (< or = 3 servings/day) and consumed a multivitamin and mineral pill daily. Beginning at week 3, subjects ingested either a vitamin C (n = 8) or placebo (n = 2) capsule, which were identical in appearance and taste. The content of the vitamin C capsule increased every two weeks (from 250 mg at weeks 3-4 to 500 mg, 1,000 mg. and 2,000 mg at weeks 5-6. 7-8. 9-10, respectively). Fasting blood samples were collected at two-week intervals and analyzed for vitamin C, total lipid hydroperoxides and Heinz bodies in packed erythrocytes incubated 24 hours at 37 degrees. RESULTS: Plasma vitamin C rose 55% in vitamin C-supplemented subjects by the end of the ten-week treatment (p < 0.05), and measures of oxidative stress decreased 60% to 90% (8.1 +/- 0.6 to 3.5 +/- 0.4 nmol/mL and 69.1 +/- 7.8% to 6.7 +/- 6.0% for total lipid hydroperoxides and Heinz bodies, respectively). Significant decreases in markers of oxidative stress were noted at the 500 mg, 1,000 mg and 2,000 mg dosages versus placebo. Antioxidant protection was similar at the 1,000 mg and 2,000 mg dosage. CONCLUSIONS: These data indicate that the antioxidant protection afforded by short-term vitamin C supplementation is maximal at the 500-1,000 mg dosage range.     

Biphasic intrauterine growth in insulin-dependent diabetic pregnancies

Early fetal growth delay (7-14 weeks of gestation) has been reported in insulin-dependent diabetic (IDD) pregnancies and in several animal models. Macrosomia is a classic feature of the infant of the IDD mother. We hypothesized therefore that a biphasic pattern of fetal growth exists in IDD pregnancies. We compared fetal growth measurements [biparietal diameter (BPD) and abdominal circumference (AC)] obtained sonographically from 106 IDD pregnancies (Class B-RT) to similar data obtained from 117 normal, nondiabetic patients. The goals for diabetic glycemic control were: fasting blood sugar less than or equal to 100 mg/dl and postprandial blood sugar less than 140 mg/dl. From one to five ultrasonographic measurements were performed at varying gestational ages in all study patients. For data analysis, one examination from each pregnancy was randomly selected by computer. Gestational age (GA) was calculated from last menstrual period and corroborated by infant physical examination (Ballard score) at birth. BPD growth pattern was biphasic in the diabetic group, described by a cubic equation: BPD = 4.99 - 0.567GA + 0.037(GA)2 - 0.0005(GA)3, R2 = 0.935. Such a biphasic pattern did not exist in the control population [BPD = -3.0323 + 0.473(gestation) - (-0.0040)(gestation)2, R2 = 0.9173]. Early growth delay was greater in fetuses that subsequently developed macrosomia (p less than 0.01). Similar results were found for AC measurements. We conclude that fetal growth delay occurs in the first half of the IDD pregnancy, followed by a phase of increased growth. The mechanism of the early growth delay is unclear. We speculate that early growth delay may be due to a "toxic" effect of glucose or other metabolite; and subsequent increased growth relates to fetal hyperinsulinism which develops from weeks 15 to 20 of gestation.     

Biphasic intrauterine growth in insulin-dependent diabetic pregnancies.

Early fetal growth delay (7-14 weeks of gestation) has been reported in insulin-dependent diabetic (IDD) pregnancies and in several animal models. Macrosomia is a classic feature of the infant of the IDD mother. We hypothesized therefore that a biphasic pattern of fetal growth exists in IDD pregnancies. We compared fetal growth measurements [biparietal diameter (BPD) and abdominal circumference (AC)] obtained sonographically from 106 IDD pregnancies (Class B-RT) to similar data obtained from 117 normal, nondiabetic patients. The goals for diabetic glycemic control were: fasting blood sugar less than or equal to 100 mg/dl and postprandial blood sugar less than 140 mg/dl. From one to five ultrasonographic measurements were performed at varying gestational ages in all study patients. For data analysis, one examination from each pregnancy was randomly selected by computer. Gestational age (GA) was calculated from last menstrual period and corroborated by infant physical examination (Ballard score) at birth. BPD growth pattern was biphasic in the diabetic group, described by a cubic equation: BPD = 4.99 - 0.567GA + 0.037(GA)2 - 0.0005(GA)3, R2 = 0.935. Such a biphasic pattern did not exist in the control population [BPD = -3.0323 + 0.473(gestation) - (?0.0040)(gestation)2, R2 = 0.9173]. Early growth delay was greater in fetuses that subsequently developed macrosomia (p less than 0.01). Similar results were found for AC measurements. We conclude that fetal growth delay occurs in the first half of the IDD pregnancy, followed by a phase of increased growth. The mechanism of the early growth delay is unclear. We speculate that early growth delay may be due to a “toxic” effect of glucose or other metabolite; and subsequent increased growth relates to fetal hyperinsulinism which develops from weeks 15 to 20 of gestation.     

Intrauterine growth retardation is associated with reduced cell cycle activity, but not myofibre number, in ovine fetal muscle

Cellular development of muscle was studied in sheep fetuses at 85 days of gestation. Large and small fetuses were compared at 100, 115 and 130 days, and an additional group of large 130-day fetuses were studied following 7 days of maternal undernutrition. Myogenesis in the peroneus longus muscle was completed between 100 and 115 days of gestation, and myofibre number did not differ between small and large fetuses. The proportion of myofibre-related nuclei identified as entering S-phase of the cell cycle was 1.7% per hour in 85-day fetuses. In large fetuses, subsequent rates were relatively constant (approximately 1.5% h(-1)), whereas in small fetuses cell cycle activity declined with age from 1.3 to 0.9% h(-1), and was 0.5% h(-1) in 130-day fetuses of restricted ewes. The constant rate of cell cycle activity in large fetuses was associated with an increasing estimated rate of muscle growth (peroneus longus (mg) = 0.831 x 10(0.024 x age [d]), r2 = 0.98), which contrasted with slow and relatively constant muscle accretion in small fetuses (8.4 mg day(-1)), and slower muscle accretion at 130 days in large fetuses from restricted ewes. Differences in DNA and RNA content in the semimembranosus muscle increased with age, large fetuses having 70% more muscle DNA, 108% more muscle RNA and 104% larger muscles than small fetuses at 130 days (all P<0.001). The results demonstrate that myonuclei accumulation, but not myofibre number, is associated with fetal growth in sheep and, therefore, with fetal nutrition during mid to late gestation.     

孕中期经腹氯化钾减胎术的临床应用

目的探讨孕中期经腹氯化钾(KCl)减胎术的方法及妊娠结局。方法选择孕中期因多胎妊娠或双胎妊娠者有1胎异常的孕妇进行超声引导下经腹KCl减胎术,分析减胎方法、术后并发症和妊娠结局等。结果 9例妊娠中期经腹KCl减胎术均成功。1例术后流产,1例晚期流产,术后2周流产率11.10%。保留双胎2例,平均分娩孕周33+4周,新生儿出生体重(1.94±0.18)kg;保留单胎4例,平均分娩孕周39+3周,新生儿出生体重(3.26±0.14)kg;妊娠随访中1例。结论超声引导下孕中期经腹KCl减胎术可作为避免多胎妊娠及异常胎儿出生的安全、简便、有效方法。     

Tei指数在胎儿宫内生长受限心脏功能检测中的价值

目的：探讨Tei指数在孕晚期胎儿宫内生长受限心脏功能监测中的应用价值。方法：选择在孕晚期发现的宫内生长受限胎儿40例，同时选取正常胎儿40例，在28~32周，33~38周，38周以上3个孕周时段多次测量左、右室Tei指数，进行统计学分析。结果：宫内生长受限胎儿Tei指数测值随孕周而增加，在28~32周、33~38周、38周以上3个时间段左、右心室Tei指数测值均高于正常胎儿组，比较差异有统计学意义（P〈0.01）。结论：Tei指数在孕晚期胎儿宫内生长受限心脏功能监测中有较大价值。     

Lack of effect of vitamin E therapy on the anemia of patients receiving hemodialysis

We conducted a prospective, randomized, double-blind therapeutic trial of vitamin E as an erythropoietic agent in a group of patients with chronic renal failure who were undergoing chronic hemodialysis. Sixteen patients received 400 IU of vitamin E (d-alpha-tocopheryl acetate) by mouth twice daily and 19 patients received a placebo twice daily for 20 wk. The serum vitamin E concentration increased from 1.3 to 2.6 mg/dl in the treated group and decreased from 1.3 to 1.1 in the placebo group. For the treated group the initial hematocrit was 24.8 +/- 3.0 (mean +/- SD) and the final hematocrit was 25.8 +/- 3.8. For the placebo group the initial hematocrit was 24.9 +/- 3.0 and the final hematocrit was 23.5 +/- 2.7. The treated group received a total of 40 blood transfusions, and the placebo group received a total of 35 blood transfusions. Thus, vitamin E had no effect on the anemia or transfusion requirements of patients undergoing chronic hemodialysis for chronic renal failure.     

Effects of oral vitamin E and beta-carotene supplementation on ultraviolet radiation-induced oxidative stress in human skin

BACKGROUND: Ultraviolet radiation (UVR) generates reactive oxygen species in skin that can play a role in skin damage, but reports about the photoprotective properties of oral antioxidant supplements are conflicting. OBJECTIVE: We examined the ability of 2 lipid-soluble antioxidants, vitamin E and beta-carotene, to reduce markers of oxidative stress and erythema in human skin exposed to UVR. DESIGN: Sixteen healthy subjects took either alpha-tocopherol (n = 8; 400 IU/d) or beta-carotene (n = 8; 15 mg/d) for 8 wk. Biopsy samples before and after supplementation were taken from unexposed skin and skin 6 h after 120 mJ/cm(2) UVR. The effects of supplements on markers of oxidative stress in skin and the minimal erythema dose to UVR were assessed. RESULTS: Supplementary vitamin E was bioavailable, the plasma concentration increased from 14.0 +/- 0.66 (x +/- SEM) to 18.2 +/- 0.64 mug/mL (P < 0.01), and the skin concentration increased from 0.55 +/- 0.09 to 1.6 +/- 0.19 ng/mg protein (P < 0.01). Supplementary beta-carotene increased plasma concentrations from 1 +/- 0.3 to 2.25 +/- 0.3 mug/mL (P < 0.05), but skin concentrations were undetectable. Before vitamin E supplementation, UVR increased the skin malondialdehyde concentration from 0.42 +/- 0.07 to 1.24 +/- 0.16 nmol/mg protein (P < 0.01), whereas oxidized or total glutathione increased from 9.98 +/- 0.4% to 12.0 +/- 1.0% (P < 0.05). Vitamin E supplementation significantly decreased the skin malondialdehyde concentration, but neither vitamin E nor beta-carotene significantly influenced other measures of oxidation in basal or UVR-exposed skin. CONCLUSIONS: Vitamin E or beta-carotene supplementation had no effect on skin sensitivity to UVR. Although vitamin E supplements significantly reduced the skin malondialdehyde concentration, neither supplement affected other measures of UVR-induced oxidative stress in human skin, which suggested no photoprotection of supplementation.