Sources of variation in interbirth intervals among captive bonnet macaques (Macaca radiata)

Female fitness is a function of variation in the length of females' reproductive careers, the viability of their offspring, and the frequency with which they give birth. Infant loss shortens interbirth intervals in most primate species, but we know considerably less about other factors that contribute to variation in the length of interbirth intervals within groups. In one large captive group of bonnet macaques, maternal parity, age, experience, family size, and recent reproductive history are all associated with variation in the length of intervals that follow the birth of surviving infants. Primiparous females have the longest interbirth intervals, while multiparous females who have produced surviving infants in the past and have raised their last infant successfully have the shortest interbirth intervals. Infant sex and maternal rank have no direct effect upon the length of interbirth intervals. One of the underlying causes of variation in the length of interbirth intervals after surviving births seems to be variation in the timing of conceptions among females. Females who conceive early in the mating season tend to have shorter interbirth intervals than other females. However, females who are multiparous, experienced, and have recently raised infants have late conceptions and short interbirth intervals.     

Analysis of infant carrying in large,well-established family groups of captive marmosets (<Emphasis Type="Italic">Callithrix jacchus</Emphasis>)

To assess the pattern of infant carrying across time and family members, we counted which animals in 13 well-established family groups of captive-bred marmosets (Callithrix jacchus) carried neonates during the first 8 weeks of life. The neonates were carried almost continuously for the first 3 weeks and then spent progressively more time independently. The mother did most of the carrying for the first 2 weeks, her contribution rising from day 1 to day 3 and declining thereafter. The contribution of the father was high on day 1, declined during the first week, and then rose to a peak in the fourth week. The contribution of the siblings rose sharply during the first week and declined thereafter. There was no overall difference in amount of infant carrying by each parent. The contribution of each sibling was small although in these large families the total contribution by siblings was large. These data may differ from previous observations because the breeding pairs were very well established, the families were large, and all except the youngest animals were very experienced in rearing and carrying. These data emphasise the group-dynamic nature of infant carrying in a primate species.     

Elevated urinary testosterone excretion and decreased maternal caregiving effort in marmosets when conception occurs during the period of infant dependence

The proximate mechanisms that regulate transitions in mammalian female reproductive effort have not been widely studied. However, variation in circulating levels of the androgenic steroid hormone testosterone (T) appears to mediate a trade-off between investment in current and future offspring in males [Ketterson, E.D., Nolan, V., Jr., 1992. Hormones and life histories: an integrative approach. Am. Nat. 140, S33-S62; Ketterson, E.D., Nolan, V., Jr., 1994. Hormones and life histories: an integrative approach. In: L.A. Real (Ed.), Behavioral Mechanisms in Evolutionary Ecology, University of Chicago Press, Chicago, pp. 327-353; Ketterson, E. D., Nolan, V., Jr., 1999. Adaptation, exaptation, and constraint: A hormonal perspective. Am. Nat. 154S, S4-S25]. The purpose of this study was to investigate the possibility that T is also associated with transitions in the reproductive effort of females, by examining the relationship between urinary T excretion, maternal caregiving behavior, and the timing of the postpartum conception in female Wied's black tufted-ear marmosets (Callithrix kuhlii). We examined the maternal carrying effort and peripartum T profiles of six females across two conditions: (1) when they conceived during the period of infant dependence (DPID), such that gestation was coupled with lactation; and (2) when the same females conceived after the period of infant dependence (APID). We also assessed the relationship between postpartum T levels and caregiving effort. When female marmosets conceived DPID, they dramatically reduced their caregiving effort, and had higher levels of urinary T, relative to when they conceived APID. Further, the litter-to-litter changes in maternal caregiving effort that we observed were related to variation in urinary T excretion; as weekly levels of urinary T excretion increased, concurrent caregiving effort declined. Our results suggest that variation in T secretion may regulate transitions in female reproductive behavior, and that the regulation of male and female parental behavior may be mediated by homologous neuroendocrine mechanisms.     

Quantification of Bifidobacterium spp., Escherichia coli and Clostridium difficile in faecal samples of breast-fed and formula-fed infants by real-time PCR

To determine the influence of either exclusive breast-feeding or formula feeding on both composition and quantity of the gut microbiota in infants, we have developed real-time, quantitative PCR assays for the detection of Bifidobacterium spp. and Clostridium difficile. Furthermore, we have monitored the prevalence and counts of Escherichia coli by applying a previously described real-time PCR assay. We found all 100 infants tested to be colonized by Bifidobacterium spp. The bifidobacterial counts were comparable between the 50 breast-fed and 50 formula-fed infants with median values of 10.56 log10 and 10.24 log10 CFU g(-1) wet weight faeces, respectively. C. difficile was detected in 14% of the breast-fed and 30% of the formula-fed infants. In addition, the C. difficile counts were significantly lower in breast-fed infants than in the formula-fed group (median values of 3.28 log10 and 7.43 log10 CFU g(-1), respectively; p=0.03). The prevalence of E. coli in the breast-fed and formula-fed group was 80% and 94%, respectively. Also, the E. coli counts in colonized infants was significantly lower in the breast-fed infants than in the formula-fed group (median values of 9.11 log10 and 9.57 log10 CFU g(-1), respectively; p=0.004). We conclude that the prevalence and counts of C. difficile as well as E. coli are significantly lower in the gut microbiota of breast-fed infants than in that of formula-fed infants, whereas the prevalence and counts of Bifidobacterium spp. is similar among both groups.     

新生儿败血症的临床研究

目的探讨新生儿败血症的发病特点和近年来细菌学演变情况.方法对57株新生儿败血症患儿发病特点和实验室检查结果进行分析.结果出生～7天25株(44%),擦"马牙”31例(54%),脐部红肿或分泌物18例(32%),硬肿症16例(28%),均有不同程度黄疸.分离出77株细菌,其中金黄色葡萄球17株(22%),表皮葡萄球菌18株(23%),L型细菌35株(45%).治疗前血清疸红素(TBS)为(318.6±67.8)μmol/L.结论早期新生儿,擦"马牙”及新生儿硬肿症患儿败血症发病率高.可引起黄疸.金葡菌和表葡菌仍是新生儿败血症的主要病原菌,细菌L型明显增多.     

Early life environment and adult height: The case of Chile

In this paper, we analyze the relationship between adult height and early-life disease environment, proxied by the infant mortality rate (IMR) in the first year of life, using cohort-region level data for Chile for 1960–1989. IMRs show a remarkable reduction of 100 points per thousand over this thirty-year period, declining from 119.4 to 21.0 per thousand. We also document a 0.96 cm increase in height per decade.We find that the drop in IMRs observed among our cohorts explains almost all of the long-term trend in rising adult heights, and that per capita GDP does not appear to have any predictive power in this context. Results are robust in a variety of specifications, which include area and cohort dummies, an adjustment for internal migration, and urbanization rates. Our results point to the long-term effect of a public health policy.     

轮状病毒肠炎患儿的临床表现与肠道外多脏器损伤的相关性

目的：探讨轮状病毒（RV）肠炎患儿的在腹泻、呕吐、发热及脱水程度等临床表现与肠外多脏器损伤的相关性。方法：选取2009年1月-2012年6月在我院儿科住院治疗的轮状病毒肠炎患儿193例,留取其大便、尿液及血液,以便进行大便常规、肠道细菌培养、RV抗原检查、尿常规、血常规以及生化指标检测,所有患儿行胸部X线、心电图等常规检查,并根据诊断标准判断其肠外脏器损伤情况。结果：193例RV肠炎患儿中有呼吸系统损伤120例,占62．17％,心肌损伤82例,占42．49％,肝脏损伤63例,占32．64％,肾脏损伤22例,占11．40％,神经系统损伤15例,占7．77％;呕吐持续≥3d与呼吸系统损伤、肾脏损伤及神经系统损伤有相关性,差异有统计学意义（P〈0．05）;腹泻≥10次／d与呼吸系统损伤有相关性,差异有统计学意义（P〈0．05）;发热持续≥3d及中重度脱水与心肌损伤、肝脏损伤、肾脏损伤及神经损伤有相关性,差异有统计学意义（P（0．05）。结论：RV肠炎患儿临床表现严重程度与肠外脏器损伤存在一定的相关性。     

HBsAg阴性母亲及其婴儿乙肝疫苗接种情况和免疫效果研究

目的：了解乙肝表面抗原阴性（HBsAg阴性）母亲及其婴儿乙肝疫苗接种情况及抗-HBs滴度水平,从而为今后针对该特殊人群进行更好的乙肝疫苗免疫策略提供依据。方法：2010年5月～2010年10月,对陕西省227对HBsAg阴性母亲及其婴幼儿（月龄为8～24月）进行流行病学调查并采集血液标本,对母婴血清抗-HBs进行定性及定量检测。结果：母亲乙肝表面抗体（抗-HBs）阳性率为45.4%,抗-HBs平均滴度为12.88 mIU/mL（95%CI：8.91-18.19）。婴儿乙肝疫苗首针、第二针和第三针的及时接种率分别为95.2%,93.8%和85.9%。婴儿抗-HBs阳性率为77.1%,抗-HBs平均滴度为37.15 mIU/mL（95%CI：28.18-48.98）。结论：婴儿乙肝疫苗首针及时接种率较高,但三针全程及时接种率仍需提高。母亲抗-HBs阳性率较低,应当重视HBsAg阴性孕龄妇女的乙肝疫苗接种及乙肝标志物的检测,从而提高该人群的乙肝免疫水平。     

Relationship Between Infant and Mother Circadian Rest-Activity Rhythm Pre- and Postpartum,in Comparison to an Infant With Free-Running Rhythm

Some infants show a free-running rhythm in their rest-activity. We do not know why, nor do we know exactly what the entrainment factors are for the development of the normal 24-h rest-activity rhythm. Actigraphic recordings on 10 primiparae during late pregnancy and these mothers and their infants during the 2nd, 6th, and 12th wks after birth were made over 3–5 continuous days to investigate maternal and infant entrainment. One infant showed a free-running rest-activity circadian rhythm. In late pregnancy, the period in the autocorrelogram of the mother with the free-running infant was longer than the significant period of the mean autocorrelogram of the mothers with non-free-running infants. The finding of this study indicates the free-running rhythm of infant is not reset by maternal entrainment factors. (Author correspondence: nishihara-kk@igakuken.or.jp)     

Age-related,interindividual, and right/left differences in anterior-posterior foot pressure ratio in preschool children

Background

This study aimed to examine age-related, interindividual, and right/left differences in anterior-posterior foot pressure ratio in 764 preschool children (364 boys and 400 girls) aged 3.5-6.5 years.

Methods

Subjects maintained an upright standing posture for 10 seconds on the Footview Clinic, an instrument designed to calculate the anterior-posterior foot pressure ratio. The ratio of anterior foot pressure in each subject’s right and left feet was selected as a variable, and the mean of a 10 s measurement was used for analysis.

Results

The ratio of anterior foot pressure was significantly larger in the right foot than in the left foot. With regard to age, the ratio of anterior foot pressure was significantly larger in children aged over 4.5 years than in children aged 3.5 years. It was also larger in children aged 6 and 6.5 years than in children aged 4 years. Interindividual differences in variables were large, and coefficients of variance were highest in children aged 3.5 years and lowest in children aged 6.5 years.

Conclusions

In conclusion, anterior foot pressure increases with age in preschool children. Interindividual differences in anterior foot pressure are large and tend to decrease with age. Furthermore, the anterior foot pressure is slightly higher in the right foot than in the left foot. These results will be useful for various studies, such as examining relationships between the anterior-posterior foot pressure ratio and factors, such as untouched toes, physical fitness, and level of exercise.