Estimates of Water Ingestion in Formula by Infants and Children Based on USDA's 1994–1996 and 1998 Continuing Survey of Food Intakes by Individuals

Assessment of risk to infants and children resulting from the ingestion of contaminants in water is an important component of the analysis of possible environmental hazards. Children and infants represent a sensitive life stage because exposure to contaminants in early life can have developmental and long-lasting adverse effects. Children and infants tend to ingest relatively large amounts of water on a bodyweight-adjusted basis, especially those that are fed in early life with formula that is re-constituted or diluted with water. This article presents statistical estimates of the amounts of community water ingested by formula-fed infants based on nationwide sample survey data that support identification of respondents who consume formula and the amounts of water they ingest. Included are specific estimates of the amounts of community water ingested in formula. Estimates of total community water ingestion by children and infants who consume formula can be especially useful in exposure assessment since they represent a highly exposed population. For example, mean community water ingestion by infants 1 to 3 months of age who consume formula is 627 mL/day (136 mL/kg/day) and the 95th percentile is 1096 mL/day (290 mL/kg/day).     

Actigraphic motor activity during sleep from infancy to adulthood

A secondary analysis of longitudinal and cohort studies was carried out to quantitatively investigate the motor activity pattern, recorded through actigraphy, during the first six hours of nocturnal sleep. The first study was of longitudinal nature. Ten healthy participants (four females) were monitored three times, at baseline (T1) when they were infants (mean age 7.10 ± 0.32 months), at the first follow-up examination (T2) around 4 months later (mean age 11.20 ± 0.63 months) and at the second follow-up (T3) around three years later, when they were preschoolers (mean age 4.68 ± 0.14 years). At T1, T2 and T3 each participant wore the actigraph Basic Mini-Motionlogger (Ambulatory Monitoring, Inc., Ardsley, NY, USA) over at least two consecutive nycthemeral cycles, with the aim to measure the mean hourly motor activity count. Seven- and 11-month-old infants had a higher level of motor activity over the night compared to preschoolers. Furthermore, motor activity increased as the night progressed, with a pronounced increment at both T1 and T2, while at T3 such an increase was less marked. The second study was cross-sectional and aimed to explore the motor activity pattern, using actigraphy, during the first six hours of nocturnal sleep in multiple-age healthy groups, from infancy to adulthood. We assigned participants to eight groups according to age: 20 (five females) aged around 10 months old (mean age 10.65 ± 0.67 months); 13 (nine females) aged around 4 years (mean age 4.38 ± 0.51 years); 21 (10 females) aged around 10 years (mean age 9.67 ± 0.91 years); 21 (nine females) aged around 20 years (mean age 19.33 ± 2.44 years); 20 (10 females) aged around 30 years (mean age 29.80 ± 1.99 years); 20 (15 females) aged around 40 years (mean age 40.70 ± 1.26 years); 20 (11 females) aged around 50 years (mean age 50.15 ± 2.80 years) and 20 (nine females) aged around 60 years (mean age 59.25 ± 3.23 years). The participants aged between 10 and 60 years wore the actigraph Basic Mini-Motionlogger over seven consecutive nycthemeral cycles (infants and preschoolers wore the actigraph over at least two consecutive nycthemeral cycles), with the aim to measure the mean hourly motor activity count. The results indicated a significantly higher motor activity count in 10-month-old infants compared to all the remaining age groups. Moreover, the pattern of motor activity of 10-month-old infants was different from that of all other groups, with the highest motor activity counts from the second to the sixth hour of sleep. Considered as a whole, the results of both studies converge regarding the high motor activity detected among infants, which could be explained by the presence of a maturational process that has not yet been fully completed at this stage of life. In both studies, only the motor activity of infants was above the cutoff level established for normal adults, highlighting the need to establish a specific cutoff value for infants.     

脐血IL-6、IL-8、TNF-a在早产儿脑损伤中的临床意义及预测价值

目的研究脐血白介素-6(IL-6)、白介素-8(IL-8)和肿瘤坏死因子-a(TNF-a)在34周前早产儿脑损伤中的临床意义及预测价值。方法对59例34周前出生早产儿用酶联免疫吸附试验检测脐血IL-6、IL-8、TNF-a;将母亲的胎盘胎膜组织行病理学检查,诊断有无绒毛膜羊膜炎;早产儿出生后72 h内头颅超声检查,诊断有无脑损伤。结果 (1)早产儿脑损伤组脐血IL-6[(7.69±1.69)μg/L]、IL-8[(3.87±0.26)μg/L]及TNF-a[(3.67±1.12)μg/L]明显高于无脑损伤组[分别为(5.78±0.59)μg/L、(1.79±0.66)μg/L、(1.91±0.37)μg/L],2组比较差异有统计学意义(P<0.05);母亲患绒毛膜羊膜炎组脐血IL-6[(6.98±0.17)μg/L]、IL-8[(3.27±0.27)μg/L]和TNF-a[(3.24±1.37)μg/L]明显高于无绒毛膜羊膜炎组[分别为(6.13±0.15)μg/L、(2.04±0.79)μg/L、(2.07±0.54)μg/L],2组比较差异有统计学意义(P<0.05);(2)应用ROC工作曲线进行分析,脐血IL-6≥6.46μg/L、IL-8≥2.0μg/L、TNF-a≥2.42μg/L作为诊断早产儿脑损伤标准时,其灵敏度分别为95.5%、95.5%和100%;特异度分别为94.6%、70.3%和97.3%;(3)母亲有绒毛膜羊膜炎时,早产儿脑损伤发生率明显升高。结论脐血IL-6、IL-8和TNF-a不仅反映母亲的感染情况和早产儿脑损伤,并且对早产儿脑损伤具有一定的预测价值。     

伊氏锥虫在人胚肺成纤维细胞和在新生鼠肾成纤维细胞型细胞中的体外培养

在HEPES缓冲,含15—20％胎牛血清,100单位青霉素/ml,100微克链霉素/ml的RPMI-1640培养基中,用人胚肺成纤维细胞(KMB)和新生鼠肾成纤维细胞型细胞(ZUKF)作支持细胞,成功地使伊氏锥虫(Trypanosoma evansi)正常动基体株(kinetoplastic strain)和异常动基体株(dyskinetoplastic strain)在37℃含5％ CO_2的二氧化碳培养箱中连续培养达60天以上,并保持其对小鼠的高度感染力和致病力。这是迄今为止首次利用来源于人的细胞作支持细胞连续培养家畜非洲锥虫血液型成功的报告。实验结果表明伊氏锥虫体外培养成功与否对提供支持细胞的宿主是否有感染性无必然的联系。此外,利用Baltz氏等建立的无支持细胞培养系统,我们亦成功地使上述两伊氏锥虫株在体外连续繁殖,并保持对小鼠的高度感染力和致病力。     

The roles of DNA methylation of NR3C1 and 11β-HSD2 and exposure to maternal mood disorder in utero on newborn neurobehavior

Exposure to maternal mood disorder in utero may program infant neurobehavior via DNA methylation of the glucocorticoid receptor (NR3C1) and 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD-2), two placental genes that have been implicated in perturbations of the hypothalamic pituitary adrenocortical (HPA) axis. We tested the relations among prenatal exposure to maternal depression or anxiety, methylation of exon 1F of NR3C1 and 11β-HSD-2, and newborn neurobehavior. Controlling for relevant covariates, infants whose mothers reported depression during pregnancy and showed greater methylation of placental NR3C1 CpG2 had poorer self-regulation, more hypotonia, and more lethargy than infants whose mothers did not report depression. On the other hand, infants whose mothers reported anxiety during pregnancy and showed greater methylation of placental 11β-HSD-2 CpG4 were more hypotonic compared with infants of mothers who did not report anxiety during pregnancy. Our results support the fetal programming hypothesis and suggest that fetal adjustments to cues from the intrauterine environment, in this case an environment that could be characterized by increased exposure to maternal cortisol, may lead to poor neurodevelopmental outcomes.     

Electrophysiological Responses of Nucleus Tractus Solitarius Neurons to CCK and Gastric Distension in Newborn Lambs

The effect of cervical vagus nerve stimulation, gastric distension and CCK-8S administration was studied on the activity of 120 neurons located in the nucleus tractus solitarius (NTS) of anesthetized newborn lambs. One hundred cells responded to the three different inputs.The distribution of the cells in the NTS was from 3 mm rostral to 3 mm caudal to the obex, the major responsive cells being located at the level of the obex. Neurons were either excited or inhibited by gastric distension and CCK-8S, and the responses to these two stimuli were always in the same direction. A small number of cells responded to gastric distension and CCK-8S but not to vagus nerve stimulation.Injection of the CCK-A receptor antagonist 2-NAP abolished both the responses to CCK-8S and to gastric distension. The results are consistent with the idea that CCK-8S acts directly on vagal mechanoreceptive endings in the gastric corpus close to duodenum.These results from lambs may reflect the pathway by which gastric distension and peripheral CCK-8S modulate NTS cells activity during colostrum ingestion, which could in turn activate structures related to learning and memory processes involved in the development of mother preference.     

低出生体重儿肠道菌群及肠道屏障功能的研究

目的 研究低出生体重儿的肠道菌群分布情况和肠道屏障功能的变化。方法 以低出生体重儿（1 500 g≤体重＜2 500 g）为研究对象,采用16S rRNA荧光定量PCR技术和JY-DLT肠道屏障功能分析系统检测低出生体重儿出生后第7天粪便中双歧杆菌、乳杆菌、大肠埃希菌、肠球菌4种细菌的含量以及血清中的二胺氧化酶、D-乳酸和细菌内毒素的浓度,比较正常新生儿与低出生体重儿肠道菌群和肠道屏障功能的差异,分析不同喂养方式、并发症对低出生体重儿肠道菌群及肠道屏障功能的影响。结果 （1）低出生体重儿组粪便中大肠埃希菌、肠球菌、乳杆菌、双歧杆菌含量均明显低于健康新生儿组（P＜0.05）,血清中二胺氧化酶、D-乳酸高于健康新生儿组（P＜0.05）,细菌内毒素水平差异无统计学意义（P＞0.05）。（2）母乳喂养组低出生体重儿粪便中双歧杆菌和乳杆菌含量明显高于乳制品喂养组（P<0.05）,且血清中二胺氧化酶和和D-乳酸含量低于乳制品喂养组（P<0.05）,细菌内毒素水平差异无统计学意义（P＞0.05）。（3）无并发症组低出生体重儿粪便中乳杆菌和双歧杆菌含量明显高于有并发症组（P＜0.05）,其血清中二胺氧化酶、D-乳酸和细菌内毒素水平均低于有并发症的低出生体重儿（P＜0.05）。结论 低出生体重儿的肠道菌群和肠道屏障功能都与正常新生儿存在差异,母乳喂养有助于肠道有益菌的定植和肠道屏障功能的恢复。     

Role of bradykinin in the antihypertr. ophic effects of enalapril in the newborn pig heart

Rapid growth of the left ventricle of the newborn pig heart can be restrained by treating piglets with the angiotensin converting enzyme inhibitor, enalapril maleate. This reduced rate of growth is reflected in vitro by reduced rates of ribosome formation and protein synthesis, and may be due to decreased availability of angiotensin II (All), a potentially hypertrophic agent; decreased numbers of All receptors; increased availability of bradykinin, a potentially antihypertrophic agent; or reduced hemodynamic load on the left ventricle. Because enalapril decreases degradation of bradykinin, the role of bradykinin as an inhibitor of cardiac growth in the newborn heart was investigated. Addition of 1 × 10^–5 M bradykinin and 1 × 10^–6 Menalapril to the perfusate of isolated hearts from 2 day old piglets did not significantly alter heart rate, contents of ATP or creatine phosphate or rates of ribosome formation or protein synthesis during 1 h of perfusion. Similarly, exposure of myocytes isolated from the left ventricular free wall of piglets to 5 × 10^–6 M bradykinin for 72 h did not alter the rate of [³H]-phenylalanine incorporation into total protein. The reduced rate of left ventricular growth in vivo caused by enalapril administration was not reversed by simultaneous treatment with the specific bradykinin receptor antagonist, HOE 140. HOE 140 alone did not alter ventricular growth as compared to hearts from untreated piglets. In summary, these results demonstrate that the reduced rate of left ventricular growth in vivo and the reduced rate of ribosome formation and protein synthesis in the left ventricle in vitro after enalapril treatment of piglets is not the result of an inhibitory effect of bradykinin on cardiac growth.     

Culture-independent analysis of fecal microbiota in infants, with special reference to Bifidobacterium species

Fecal microbiota of 31 breast-fed, 26 mix-fed, and 11 bottle-fed infants were analyzed by using terminal restriction fragment length polymorphism (T-RFLP), and culture method. We first determined the total and cultivated bacterial counts in infant fecal microbiota. Only approximately 30% of bacteria present in fecal microbiota were cultivable while the remainder was yet-to-be cultured bacteria. Sixty-eight fecal samples were divided into two clusters (I and II) by T-RFLP analysis, and then subdivided into five subclusters (Ia, Ib, IIa, IIb and IIc). There was no clear relationship between clusters and feeding method. A proportion of bifidobacteria was detected in the fecal material by PCR method using species-specific primers. The predominant Bifidobacterium spp. was Bifidobacterium longum longum type (43 samples (63.2%)), followed by B. longum infantis type (23 samples (33.8%)) and B. breve (16 samples (23.5%)). The distribution of Bifidobacterium spp. was similar in the three feeding groups. In contrast, the high incidence of B. breve in cluster I, especially subcluster Ia and B. longum longum type in cluster II, especially subcluster IIa and IIc were characterized by T-RFLP method. Our results showed that the colonization of Bifidobacterium spp. in infant feces correlated with the T-RFLP clusters.     

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.