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1.
OBJECTIVE: To evaluate leptin values in placental cord blood of newborns with normal intrauterine growth after 30-42 weeks of gestation. DESIGN: Leptin, a protein encoded by the ob gene, plays an important role in the regulation of feeding behaviour and energy balance in rodents, primates and humans. The presence of leptin in human amniotic fluid and cord blood has recently been reported in human gestations at term and the possible role of leptin in human fetal growth suggested. However, little is known of leptin synthesis during human foetal development. Thus, the aim of our work was to measure leptin (RIA, Linco Research, Inc.) in placental cord blood of human newborns at different fetal ages. PATIENTS: One hundred and twenty-six healthy newborns with normal intrauterine growth were studied. Twenty-nine were preterm (15 males and 14 females; gestational age: 30-36 weeks) and 99 were at term (49 males and 48 females; gestational age: 37-42 weeks). RESULTS: Leptin values increase progressively throughout gestation from 1.30 +/- 0.53 ng/ml at 30 weeks of gestation to 7.98 +/- 4.96 ng/ml (mean +/- SD) at term, and correlate positively with birth weight (r = 0.56, p < 0. 005, n = 126), length (r = 0.37, p < 0.005, n = 126), BMI (r = 0.57, p < 0.005, n = 126), head circumference (r = 0.37, p < 0.005, n = 126), gestational age (r = 0.48, p < 0.005, n = 126) and placental weight (r = 0.38, p < 0.003, n = 59). Leptin values are statistically significantly lower (p < 0.005) preterm (median: 2.05 ng/ml; range: 0.7-8.3 ng/ml) than at term (median: 7.0 ng/ml; range: 1.1-28.1 ng/ml). Leptin values are also significantly (p < 0.005) higher in females (median: 7.2 ng/ml; range: 0.9-23.6 ng/ml, n = 62) than in males (median: 4.8 ng/ml; range: 0.7-28.1 ng/ml, n = 64), although there are no differences in weight (2,864 +/- 536 g in females vs. 2,937 +/- 744 g in males). Multiple regression analysis shows weight to be a positive sex-independent predictor of serum leptin values (p < 0.0005). Sex also proves to be a predictor of leptin, independently of weight and is higher in females than in males (p < 0.003). CONCLUSION: Leptin is present in placental human cord blood after 30-42 weeks of gestation. Newborn weight and sex are independent predictors of leptin values.  相似文献   

2.
Variation in anogenital distance (AGD) in female newborn rats depends upon androgenization secondary to transplacental/transmembraneous testosterone from adjacent intrauterine male siblings. Since the size of the sexually dimorphic nucleus of the preoptic area of the hypothalamus (SDN-POA) and the degree of pituitary sensitivity to GnRH are neuroendocrine markers of neonatal androgenization, we compared these to AGD in castrated adult male and female rats. Compared to 1-day-old female rats with short AGD (less than or equal to 1.4 mm), 1-day-old female rats with long AGD (greater than 1.4 mm) had significantly larger SDN-POA volumes as adults. In contrast, LH secretion following GnRH injection did not differ in the two subgroups. Our results emphasize that some endpoints of central nervous system sexual differentiation in the adult rat are predicted by the appearance of a masculinized genital tract at birth. It follows that the complete evaluation of potential androgenizing agents will require systematic assessment of multiple morphologic and functional endpoints.  相似文献   

3.
Mean +/- s.d. testosterone concentrations in the peripheral plasma of 21- and 22-day-old male fetuses (1.32 +/- 0.43 ng/ml) were significantly (P less than 0.05) higher than those in the umbilical venous plasma (0.37 +/- 0.08 ng/ml). Testosterone concentrations in umbilical venous plasma of male and female (0.29 +/- 0.06 ng/ml) fetuses and in peripheral plasma of female fetuses (0.36 +/- 0.10 ng/ml) were not significantly different. Androsterone levels measured in umbilical venous plasma of male (11.5 +/- 2.5 ng/ml) and female (12.3 +/- 2.1 ng/ml) fetuses were nearly as high as those in peripheral plasma (males, 12.9 +/- 3.1; females, 13.3 +/- 3.5 ng/ml). There were high concentrations of androsterone in the placentas of male (33 +/- 4 ng/g) and female (33 +/- 5 ng/ml) fetuses, suggesting that this organ is the major source of fetal androsterone. We also conclude that a major part of the testosterone present in female fetuses is secreted by the placentas.  相似文献   

4.

Background

Anogenital distance (AGD), a sexually dimorphic measure of genital development, is a marker for endocrine disruption in animal studies and may be shorter in infant males with genital anomalies. Given the correlation between anogenital distance and genital development, we sought to determine if anogenital distance varied in fertile compared to infertile adult men.

Methods

A cross sectional study of consecutive men being evaluated for infertility and men with proven fertility was recruited from an andrology clinic. Anogenital distance (the distance from the posterior aspect of the scrotum to the anal verge) and penile length (PL) were measured using digital calipers. ANOVA and linear regression were used to determine correlations between AGD, fatherhood status, and semen analysis parameters (sperm density, motility, and total motile sperm count).

Findings

A total of 117 infertile men (mean age: 35.3±17.4) and 56 fertile men (mean age: 44.8±9.7) were recruited. The infertile men possessed significantly shorter mean AGD and PL compared to the fertile controls (AGD: 31.8 vs 44.6 mm, PL: 107.1 vs 119.5 mm, p<0.01). The difference in AGD persisted even after accounting for ethnic and anthropomorphic differences. In addition to fatherhood, on both unadjusted and adjusted linear regression, AGD was significantly correlated with sperm density and total motile sperm count. After adjusting for demographic and reproductive variables, for each 1 cm increase in a man''s AGD, the sperm density increases by 4.3 million sperm per mL (95% CI 0.53, 8.09, p = 0.03) and the total motile sperm count increases by 6.0 million sperm (95% CI 1.34, 10.58, p = 0.01). On adjusted analyses, no correlation was seen between penile length and semen parameters.

Conclusion

A longer anogenital distance is associated with fatherhood and may predict normal male reproductive potential. Thus, AGD may provide a novel metric to assess reproductive potential in men.  相似文献   

5.
Boars from sows with elevated plasma cortisol during pregnancy have shorter anogenital distance (AGD), a trait associated with subfertility. Since gestating sows often experience summer heat stress (HS), a mouse model was used to evaluate the effect of prenatal HS on AGD and fertility; efficacy of the heat stress-mitigating supplement Artemisia absinthium (AB) was also evaluated. Dams were treated from d 8–18 of gestation, residing in ambient temperatures from 0700 to 1900 h. From 1900 to 0700 h females were exposed to 34.13±0.27 °C (HS) with access to water (HSW; n=9), HS with access to a 1% w/v decoction of AB (HSA; n=9), 20.81±0.20 °C (thermal neutral; TN) with water (TNW; n=10) or TN with AB (TNA; n=10). Daily liquid consumption was measured from d 6–18, and tail temperature was recorded at 0700 and 1900 h from d 8–18. Progeny weight and AGD were recorded at birth and weaning. At maturity, males were mated to non-littermate females from each treatment; these females were euthanized after 16 d of TN gestation. Reproductive traits were compared among all male/female treatment combinations; testes were weighed. Average liquid intake differed among treatments with HS and AB animals drinking more (P<0.0004). A treatment by time interaction for tail temperature (P<0.001) was observed; HS increased tail temperature of HSA and HSW animals similarly compared to TNA and TNW. Treatment affected (P<0.01) male birth AGD (HSW shortest; P<0.07). At maturity, HSW males also had the smallest testes (P<0.02). However, we observed no differences in fertility (P>0.10). These data indicate that in utero HS decreases both male birth AGD and adult testis size, effects which maternal AB consumption mitigates.  相似文献   

6.
Antenatal testosterone exposure influences fetal neurodevelopment and gender-role behavior in postnatal life and may contribute to differences in developmental psychopathology during childhood. We prospectively measured the associations between umbilical cord blood testosterone levels at birth and childhood behavioral development in both males and females from a large population based sample. The study comprised 430 females and 429 males from the Western Australian Pregnancy Cohort (Raine) Study where umbilical cord blood had been collected. Total testosterone concentrations were determined by mass spectrometry and bioavailable testosterone (BioT) levels were calculated. At two, five, eight and ten years of age, the participants completed the Child Behavior Checklist (CBCL). Linear regression models were used to analyse the relationship between BioT concentrations (in quartiles) and CBCL scores (total, internalizing, externalizing and selected syndrome). Boys had higher mean CBCL T-scores than girls across all ages of follow-up. There was no significant relationship between cord blood BioT quartiles and CBCL total, internalizing and externalizing T-scores at age two or five to ten combined. In the syndrome score analyses, higher BioT quartiles were associated with significantly lower scores for attention problems for boys at age five, eight and ten, and greater withdrawal symptoms in pre-school girls (age five). We did not identify a consistent relationship between antenatal testosterone exposure and total, internalizing or externalizing behavioral difficulties in childhood. Higher umbilical cord BioT levels were associated with lower scores for attention problems in boys up to 10 years and more withdrawn behavior in 5-year-old girls; however, these findings were not consistent across ages and require further investigation in a larger sample.  相似文献   

7.
BACKGROUND: The mutation of the IRS-1 gene is one of the genetic risk factors which, it is speculated, is associated with insulin resistance or predisposition to type 2 diabetes. The aim of our study was to evaluate the association between the Gly972Arg polymorphism in the IRS-1 gene and birth weight in newborn children with adequate gestational age. MATERIAL AND METHODS: 100 newborn children with adequate gestational age (38-42 weeks), whose mother had no disorders during pregnancy, were studied. Genomic DNA was extracted from umbilical cord blood leukocytes, and Gly972Arg polymorphism in the IRS-1 gene was genotyped using the PCR-based method. RESULTS: Birth weight was significantly lower in the newborn with the IRS-1 Gly972Arg polymorphism compared with a control group (3161.75 +/- 380.86 g vs. 3427.92 +/- 468.86 g). Body length and head circumference at birth were also lower in the neonates with that polymorphism (54.38 +/- 3.13 cm vs. 52.69 +/- 2.91 cm, and 34.08 +/- 1.47 vs. 33.63 +/- 0.81, respectively). CONCLUSIONS: The results suggest that the Gly972Arg genotype is associated with lower birth weight, body length and head circumference in neonates with adequate gestational age.  相似文献   

8.
We consider the effects of major prenatal economic shocks experienced by mothers on two indicators of newborn-infant health, birth weight and head circumference, using detailed microdata from the UK ALSPAC survey. Controlling for physiological and socioeconomic factors, an economic shock in the first 18 weeks of gestation lowers birth weight by 40–70 g and head circumference by 2–3 mm. We find evidence of transmission via poorer maternal health due to absolute material deprivation and tobacco and alcohol consumption, but not for the endocrinological effects of increased psychosocial anxiety. The fragile-male hypothesis holds for birth weight but not for head circumference, as predicted by recent theories on gender differences in prenatal development.  相似文献   

9.
Male (N = 8) and female (N = 8) pigs were assigned to receive saline or a potent GnRH antagonist ([Ac-D2Nal1,D4-Cl-Phe2,D-Trp3,D-Arg6, D-Ala10]- GnRH*HOAc; 1 mg/kg body weight) at 14 days of age. The GnRH antagonist caused LH to decline (P less than 0.01) from 1.7 ng/ml at 0 h to less than 0.5 ng/ml during 4-32 h in males and females. Concentrations of FSH in gilts declined slowly from 75 +/- 8 to 56 +/- 5 ng/ml (P less than 0.05) at 32 h. In males FSH was low (5.7 +/- 0.5 ng/ml) at 0 h and did not change significantly. To observe the effect of long-term treatment with GnRH antagonist, 10 male and 10 female pigs, 3 days of age, were treated with saline or 1 mg GnRH antagonist per kg body weight every 36 h for 21 days. Concentrations of LH were reduced (P less than 0.01) to 0.2-0.4 ng/ml throughout the experimental period in male and female piglets treated with GnRH antagonist. Plasma FSH increased in control females, but remained suppressed (P less than 0.001) in females treated with GnRH antagonist. Treatment with the GnRH antagonist suppressed FSH levels in males on Days 8 and 16 (P less than 0.05), but not on Day 24. Treatment of females with the GnRH antagonist did not influence (P greater than 0.10) oestradiol-17 beta concentrations. Administration of GnRH antagonist to males suppressed testosterone and oestradiol-17 beta values (P less than 0.01) and reduced testicular weight (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

10.
Inhibitors of the arachidonic acid cascade were given to pregnant rats during the critical period for morphogenesis of the external genitalia. Groups treated subcutaneously (s.c.) with 0.1 or 0.25 mg/kg/day of triamcinolone acetonide (TA) on gestational days (GD) 14-19 had male fetuses on GD 20 with moderate decreases in absolute anogenital distance (AGD), but gross and histological examinations revealed no alterations to the genital tubercle (i.e., no hypospadias). The s.c. coadministration of arachidonic acid at 100 mg/kg/day had minimal to no effect on AGD in the TA-exposed groups. No effect on AGD was observed in male fetuses from groups administered aspirin orally at 150 mg/kg/day, and only a 6% decrease was observed in the 300-mg/kg/day group. Neither TA nor aspirin adversely affected AGD of female fetuses. In another study, TA was administered on GD 11-19 at dose levels of 0.05 and 0.1 mg/kg/day, and dams were allowed to deliver. High-dose male offspring examined on postcoitum day (PCD) 23, had moderate decreases in AGD. In both studies with TA, there were also significant decreases in offspring weights. The contribution of the decreased weight to the decrease in absolute AGD was examined by a variety of methods (ratio of AGD to cube root of weight or biparietal distance, comparison to weight-matched controls, and covariance analysis). We conclude that TA caused a specific decrease in AGD on GD 20 that was largely reversed by PCD 23. When examined as adults (8 weeks old), the external genitalia of TA-exposed offspring were normal. Thus, the TA-induced decreases in AGD on GD 20 did not predict irreversible malformation. TA also caused other effects, which included a somewhat flattened genital tubercle and apparently thinned and glossy skin between the tubercle and the anus in both sexes on GD 20 and PCD 23, but not as adults. In addition, there were high pup mortality and high incidences of micrognathia and omphalocele (in the 0.25-mg/kg/day group only). Aspirin at 75 or 150 mg/kg/day and a specific lipoxygenase inhibitor (L-656,224) at 1,000 or 2,000 mg/kg/day were also administered from GD 14 to 19, and no offspring effects were observed. Thus, of the three agents that potentially inhibit the arachidonic acid cascade, only triamcinolone produced moderate effects on rat external genitalia that were largely reversible.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

11.
Children born small (SGA) or large (LGA) for gestational age are prone to develop insulin resistance (IR) during childhood. Visfatin, a hormone with insulin-mimetic actions, has been associated with IR. This study was designed to examine whether serum level of visfatin is correlated with metabolic indices of IR, in prepuberty in association with the intrauterine growth pattern. The following parameters were evaluated at a mean age of 6.5±1.2 years in 155 prepubertal children born appropriate for the gestational age (AGA) (n=63), or SGA (n=42), or LGA (n=50): serum levels of visfatin, adiponectin, leptin, fasting glucose (G(F)) and insulin (I(F)), the homeostasis model assessment IR index (HOMA-IR), plasma lipids, anthropometric indices at birth and the time of evaluation, and obesity indices [waist circumference (WC), body mass index (BMI) and skinfold thickness]. The mean serum level of visfatin was lower in the SGA than in the AGA and the LGA children (9±5.2 vs. 11.8±5.1 and 12.7±5.6?ng/ml, respectively, p<0.01). Girls had lower visfatin levels than boys (10.4±4.3?ng/ml vs. 12.5±6.7?ng/ml, p<0.05). Visfatin was not correlated with IR indices. In multiple regression analysis visfatin level was positively correlated with birth weight z-score (t=2.56, beta=0.24, p<0.01) and crown to heel z-score (t=2.46, beta=0.22, p=0.014), independent of age, gender, maternal weight before pregnancy, maternal weight gain during pregnancy, BMI z-score, WC z-score, serum leptin and adiponectin, and HOMA-IR. In conclusion serum visfatin level was lower in prepubertal SGA children but not correlated with IR indices. Low birth weight was an independent predictor of visfatin level.  相似文献   

12.
An anthropometric assessment was conducted of 441 adults from six rural villages in southern Mali. As is typical for human populations, females are shorter and lighter than males. Both females (N = 320) and males (N = 121) are shorter and lighter than their U.S. counterparts. Mean weight in the sample is 53.4 +/- 8.5 kilos for females and 58.8 +/- 6.5 kilos for males. Mean height is 160.4 +/- 5.7 cm for females and 171.3 +/- 6.6 cm for males. The data for height in males are very similar to those reported from other surveys in Mali, and show no evidence for a positive secular trend in height. Mean body mass index (BMI) is 20.8 for females and 20.0 for males. These are lower than U.S. averages, but well above suggested cutoff points for malnutrition in adults. Average arm circumference is 26.5 cm for females and 26.4 cm for males. Females have relatively large arm circumferences due, in part, to the heavy manual labor they perform. Average head circumference is 53.0 cm for females and 54.8 cm for males. For both sexes, these values are more than 1 standard deviation (SD) below the U.S. means. Adult values for anthropometric measurements reflect childhood stresses of malnutrition and disease, and a lifetime of accommodation to a high-carbohydrate, low-protein diet, and hard physical labor. Females are significantly closer to the U.S. standards than males for weight, height, BMI, and arm circumference; these findings support the idea that females are buffered from environmental stresses relative to males. In addition, females exhibit significantly more variability than males for weight, arm circumference, and head circumference, but not for height, suggesting that variability in adult height does not reflect the presence or absence of female buffering or the level of environmental adversity.  相似文献   

13.
We examined effects of maternal stress on prenatal serum concentrations of testosterone and estradiol and on postnatal reproductive traits in female mice from different intrauterine positions. On Day 18 of fetal life, control females positioned in utero between two male fetuses (2M females) had higher concentrations of testosterone and lower concentrations of estradiol in serum than control female fetuses located between two females (0M females). Control females positioned between a male and a female fetus (1M females) had intermediate levels of both hormones. Prior intrauterine position in control females accounted for differences in genital morphology (length of the anogenital separation) at birth and length of estrous cycles during adulthood. Maternal stress eliminated these postnatal differences due to prior intrauterine position: all 0M, 1M, and 2M female offspring of stressed mothers exhibited postnatal traits that were indistinguishable from those of control 2M females. Maternal stress resulted in an increase of over 1 ng/ml in serum testosterone in all female fetuses; the magnitude of the increase was similar for 0M, 1M, and 2M females. There was no effect of maternal stress on serum concentrations of estradiol in 0M and 2M female fetuses. Maternal stress resulted in a dramatic change in the postnatal traits of 0M females, whereas 2M females showed no change. Since the effect of maternal stress on sex steroids was similar among fetuses from different intrauterine positions but postnatal response to maternal stress varied by intrauterine position, other components of the endocrine system may mediate effects of maternal stress on these postnatal characteristics.  相似文献   

14.
Intrauterine position (IUP) of female and male fetuses in litter-bearing mammals can affect their physiology, morphology and behavior. The relationship between anogenital distance (AGD) and IUP was used as a bioassay for the degree of exposure of female and male fetuses to hormones in utero . Based on laboratory work in several rodent species, the following predictions were made for house mice ( Mus musculus domesticus ): (1) female mice should prefer odors from males with larger AGDs because such males are more aggressive, could protect more resources, and are better parents than males with smaller AGDs; (2) male mice should prefer odors from females with smaller AGDs because these females produce more offspring and are better parents than females with larger AGDs. We also tested the prediction that within sexes, mice should avoid odors from mice with larger AGDs because such mice are more aggressive. Responses to odors in traps were used to test these predictions for house mice living in outdoor enclosures using odor-baited traps. Both predictions were confirmed. Furthermore, mice of both sexes tended to avoid odor cues from individuals of the same sex that had larger AGDs, probably to decrease chances of an aggressive encounter that could result in injury.  相似文献   

15.
Serum and temporal gland secretions (TGS) were obtained from mature wild African (Loxodonta africana) and captive Asian elephants (Elephas maximus). Samples were obtained from five cows and eight bulls culled for management purposes in Kruger National Park, South Africa, and from four females and two males residing at the Washington Park Zoo, Portland, Oregon. Our purpose was to describe the levels of the androgens, testosterone (T), and dihydrotestosterone (DHT), and to correlate these observations with sex, species and behavioral status. Male-female differences in serum T were pronounced in the Asian species, whereas male and female concentrations overlapped in the African elephant serum. Serum T concentrations in African females were greater than in Asian females. Serum DHT reflected T levels, except that the striking elevation of testosterone in Asian bulls during musth was not paralleled by equal increases in DHT levels. A species difference observed among males was higher serum T levels in nonmusth Asian bulls (1.84-5.35 ng/ml) compared to the levels in African bulls (0.38-0.68 ng/ml), except for one dominant African bull (6.64 ng/ml). This single African value was still considerably lower than the serum T values of the Asian males during musth. These musth values were the highest serum androgen concentrations: T was between 19 and 40 ng/ml (average 26.10 ng/ml). The TSG values of T and DHT were much higher than serum levels except in the Asian female. T/DHT ratios in TGS were more similar than in serum. One dominant African bull had a T TGS value of 78 ng/ml, which was much higher than the rest of the African males or females, but considerably lower than as Asian bull in musth (547 ng/ml). It seems apparent that a change in androgen status as reflected in serum and TGS levels of T and DHT precedes or is concomitant with overt alteration in behavior in the Asian male. The temporal gland appears to actively concentrate androgens in both African males and females, but in the Asian male the gland secretes only during musth when the greatest concentration of both T and DHT were observed. The apparent difference in the degree of temporal gland secretory activity between the two species suggests a more specific communicative function within the Asian male.  相似文献   

16.
To evaluate prenatal exposure to arsenic in the general population and its effects on birth size, we conducted a cross-sectional study in Dalian, China. Arsenic concentration in maternal and cord blood was detected by inductively coupled plasma-mass spectrometry and its effects on birth size were analyzed by multivariate analysis and multiple linear regression analysis. Arsenic concentrations in cord blood were significantly lower than those in maternal blood. A significant positive correlation was shown between maternal and cord blood arsenic concentrations. Maternal arsenic concentration was negatively associated with birth weight, height and chest circumference, and fetal arsenic concentration was negatively associated with head circumference. Our results indicate that arsenic exposure at environmental levels in uterus may pose adverse effects on fetal development.  相似文献   

17.
Plasma testosterone and progesterone concentrations were measured in captive woolly opossums, a didelphid marsupial originating from neotropical forests in French Guyana. Although not exposed to cyclic environmental conditions as in the field, both sexes exhibited spontaneous circannual changes in sexual hormones. Males showed synchronous variations in plasma testosterone characterized by significant elevated concentrations during April and September (8.6 +/- 1 ng/ml, N = 5) and lower levels from May to July (3.6 +/- 0.4 ng/ml). In females, synchronous periods of 2-3 successive oestrous cycles occurred. Between these periods, females remained acyclic. The oestrous cycle, determined by urogenital smears, lasted 28-45 days (n = 14) and included a 20-day spontaneous luteal phase in which progesterone concentrations reached 30-40 ng/ml plasma. Even though testosterone concentrations in paired males increased significantly in response to oestrous periods of the paired females, spontaneous circannual rhythms of sexual activity were not well synchronized between the sexes in captivity. When compared to field data, sexual activity of captive animals followed a pattern similar to that in wild animals, without any changes in males but with a delay of 3 months in females.  相似文献   

18.
Testosterone propionate, cortisone, or sesame oil vehicle were given to rats during the last week of pregnancy so that effects of the hormones on anogenital distance, breeding capacity and vaginal opening of the female progeny could be contrasted. Testosterone significantly increased anogenital distance and delayed vaginal opening of progeny. When females that had been exposed to testosterone in utero were tested for breeding capacity, a significantly smaller number mated than in the control group. Female rats that had been exposed to cortisone in utero exhibited premature vaginal opening but did not differ from controls in anogenital distance, and, unlike the testosterone-exposed rats, mated. Cortisone-exposed rats carried litters to term and the litters did not differ from those of controls in numbers of pups or numbers of living pups at birth. The pups born to cortisone-exposed rats had greater birth weights and a higher survival rate to 20 days of age than pups of controls. Results indicate that testosterone administration to rats during pregnancy is far more detrimental to the development and subsequent function of the reproductive system of female progeny than cortisone and suggest that similar changes which occur in response to maternal stress or to administration of ACTH during pregnancy are more likely to result from increases in testosterone than from increases in glucocorticoid secretion.  相似文献   

19.
The sexual behaviors of old, intact (N = 5) and old, castrated (N = 6) rhesus macaque males were compared in six series of pair tests with receptive females. The castrated monkeys were tested when untreated and when given five doses of testosterone propionate (TP; 0.004, 0.016, 0.064, 0.256, and 1.024 mg/kg of body weight) in consecutive months. The serum testosterone (T) level was determined for each male before and after each series of tests. When untreated, none of the castrated males ejaculated, and yawning was significantly less in these monkeys than in intact males-no other behavioral measures differed significantly. Within 2 weeks of daily injections of 0.004 mg of TP/kg, two males ejaculated, and all differences in measures of ejaculation were eliminated. A third male ejaculated after 1 week of treatment with 0.016 mg of TP/kg. Yawning values did not differ during and after treatment with 0.064 mg of TP/kg. Although final mean serum T levels were six times higher in castrated (24.3 ng/ml) than in intact males (4.2 ng/ml), sexual performance levels did not exceed those of intact males.  相似文献   

20.

Objective

We aimed to study the maternal retinal microvasculature at mid-trimester and its relationship with subsequent fetal growth and birth size.

Methods

We recruited 732 pregnant women aged 18-46 years in the first trimester with singleton pregnancies. All had retinal photography and fetal scan performed at 26-28 weeks gestation, and subsequent fetal scan at 32-34 weeks gestation. Infant anthropometric measurements were done at birth. Retinal microvasculature was measured using computer software from the retinal photographs.

Results

In multiple linear regression models, each 10 μm narrowing in maternal retinal arteriolar caliber was associated with decreases of 1.36 mm in fetal head circumference at 32-34 weeks gestation, as well as decreases of 1.50 mm and 2.30 mm in infant head circumference and birth length at delivery, respectively. Each standard deviation decrease in maternal retinal arteriolar fractal dimension was associated with decreases of 1.55 mm in fetal head circumference at 32-34 weeks gestation, as well as decreases of 1.08 mm and 46.42 g in infant head circumference and birth weight at delivery, respectively.

Conclusions

Narrower retinal arteriolar caliber and a sparser retinal vascular network in mothers, reflecting a suboptimal uteroplacental microvasculature during mid-pregnancy, were associated with poorer fetal growth and birth size.  相似文献   

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