Effects of chelation therapy with succimer in young rabbits of moderate lead poisoning / 中华预防医学杂志

<p><b>OBJECTIVE</b>To explore the effect of chelation therapy with succimer (DMSA) in male rabbits of moderate lead poisoning during juvenile stage.</p><p><b>METHODS</b>Twenty-four 45-day-old male New Zealand rabbits were randomly divided into three groups (therapy group, TG; positive control group, PG and negative control group, NG, n=8). The TG and PG were orally exposed to lead acetate (5 mg x kg(-1) x d(-1)) for 6 weeks. Rabbits in TG were orally supplied DMSA 1050 mg/m2 in the first week and 700 mg/m2 in the next two weeks, while the other two groups wren't blood and urinary samples of all rabbits were collected per week. The tissues and organs of all rabbits were collected after 12 weeks. The blood lead levels (BLLs) were determined by atomic absorption spectrometer. The urine lead levels and the lead contents of tissue and organ were determined by inductively coupled plasma-mass spectrometry. Histopathology of tissue and organ was observed by light microscope.</p><p><b>RESULTS</b>Compared with PG, the lead level in the morning urine of TG with DMSA chelating was increased significantly. The level was peaked at (1246.96 +/- 157.91) microg/L on the first day after chelating. While the base line was (40.97 +/- 1.77) microg/L before chelating. Meanwhile, the BLLs were sharply declined from (429.63 +/- 10.82) microg/L to (238.50 +/- 11.82) microg/L. The urine lead levels of TG decreased through the 3-week chelating and 3-week discontinuation. The urine lead levels of these two groups were significantly different (F=2934.35, P<0.01). Compared to each two groups in these three groups, there were significant difference (P<0.01). The authors found the reversion of BLLs in first week after stop chelating. The BLLs of PG presented the slow course of declining in the same time, were (135.50 +/- 7.09) microg/L, very close to the level of TG for (149.88 +/- 11.39) microg/L. Compared with treatment discontinuation for 3 weeks, the urine lead levels and the body weight gain of the therapy group increased more than that of PG, and the BLLs and the lead concentrations in tissues and organs decreased more than that of PG, and histopathology in the liver tissues and testicle tissues were improved.</p><p><b>CONCLUSION</b>DMSA chelating for the rodent models of moderate lead poisoning might reduce the BLLs and soft tissue lead contents quickly and effectively, decrease toxic effects of lead in a short period of time, thus alleviate the impairment of lead poisoning on tissues and organs by decreasing lead burden, and bring out improvement on the growth retardation caused by lead poisoning.</p>

Impact of television-watching and computer-using on sleep patterns and sleep problems of school-aged children in Shanghai / 上海第二医科大学学报

Objective To investigate the effects of television-watching and computer-using on sleep/wake patterns, sleep duration and sleep problems of school-aged children in Shanghai. Methods A total of 4 108 school-aged children from 10 primary schools of Shanghai were enrolled by multi-stage cluster sampling and surveyed by questionnaires. The information of television-watching and computer-using, family and personal condition was investigated by self-prepared questionnaire, and the Chinese version of Children's Sleep Habits Questionnaire was employed to survey the sleep behaviors of children. The effects of television-watching and computer-using on sleep/wake patterns, sleep duration and sleep problems were analyzed by multiple linear regression analysis and Logistic regression analysis. Results The percentage of children who watched television≥2 h per day was 4.1% during weekdays, and that came to 49.2% during weekends. In terms of frequency of computer-using, most children reported "rarely" (88.2%, 0-1 time/week), followed by "often" (11.0%, 2-4 times/ week) and "usually" (0.8%, 5-7 times/week). With the age increase, the percentages of children who watched television≥2 h per day and those who "often" used computer gradually increased. It was revealed by multiple linear regression analysis and Logistic regression analysis that television-watching and computer-using were not only positively correlated with later bedtime, later wake time and shorter sleep duration but also significantly associated with sleep problems such as bedtime resistance, sleep onset delay, sleep duration disorder, sleep anxiety and parasomnia. Conclusion Television-watching and computer-using exert influences on sleep behaviors of sleep/wake patterns, sleep duration and sleep problems. Concerns about the potential negative effects of television-watching and computer-using on sleep behaviors may help to promote healthy sleep patterns and improve sleep quality.

Sleep habits and sleep disturbance in school-age children of China / 中华儿科杂志

<p><b>OBJECTIVE</b>To survey the sleep habits (bedtime, wake time), sleep duration, and sleep problems in school-age children of China.</p><p><b>METHOD</b>From November to December, 2005, a total of 19,299 school-age children from 55 elementary schools of 9 cities entered the study by a cross-sectional survey. A parent-administered questionnaire and the Chinese version of the Children's Sleep Habits Questionnaire were applied to investigate children's sociodemographic characteristics and sleep behaviors, respectively.</p><p><b>RESULTS</b>The mean sleep duration was 9 hours and 10 minutes (9:10, SD:48 min) during the weekdays and 9:48 (SD: 63 min) during the weekends. In about 71.4% and 41.8% school-aged children the sleep duration per day did not reach the lowest criterion of 10 hours recommended by the Ministry of Education of China during weekdays and weekends, respectively. Sleep problems were common with prevalence ranging from 14.5% for sleep-disordered breathing to 75.3% for daytime sleepiness. Parasomnia (chi(2) = 13.76, P < 0.01) and sleep-disordered breathing (chi(2) = 119.83, P < 0.01) were more prevalent in boys than in girls; however, sleep anxiety was more prevalent in girls than in boys (chi(2) = 19.42, P < 0.01). Except for night waking, other types of sleep problems were significantly associated with age.</p><p><b>CONCLUSIONS</b>Inadequate sleep duration and sleep problems prevail among school-age children, which indicates that children's sleep health may be a major public health concern in China.</p>

Effects of moderate lead poisoning on the hippocampus tissue of rabbits in juvenile stage / 中华预防医学杂志

<p><b>OBJECTIVE</b>To understand the effects of moderate lead poisoning on the hippocampus tissue of rabbits in juvenile stage.</p><p><b>METHODS</b>Sixteen 45-day-old male New Zealand rabbits were randomly divided into blank group and lead-exposed group,8 for each group. Rabbits in the lead-exposed group were treated with 5 mg x kg(-1) x d(-1) lead acetate in their forage for 6 weeks to establish a moderate lead poisoning animal model. The blood lead levels and the lead contents in the hippocampus were determined by atomic absorption spectrometer and inductively coupled plasma-mass spectrometry respectively. Histopathology and ultra-microstructure in the hippocampus tissue were observed by light microscope and electron microscope. The NR1, NR2A and NR2B protein expressions in the CA1 hippocampal region were analyzed through immunohistochemical method.</p><p><b>RESULTS</b>Compared with those of blank group, the blood lead levels of lead-exposed group were significant increased, (428.63 +/- 9.46) vs (66.38+/-3.93) microg/L (t = 100.08, P<0.01); and lead contents of hippocampus was significantly increased, (44.57+/-2.03) vs (21.20+/-1.53) ng/g, (t = 26.05, P<0.01); the hippocampus wet weight were significant decreased, (0.735 +/-0.012) vs (0.808+/-0.010), (t =12.97, P<0.01); the coefficient of hippocampus wet weight, was (0.458 +/-0.004) vs (0.476+/-0.005), (t =7.87, P<0.01). The significant declines in both the positive rate of NR1 and NR2A in the CA1 hippocampal region for NR1: (37.44 +/- 2.05)% vs (41.81+/-2.50)% (t = 3.82, P<0.01) and for NR2A: 21.97+/-1.08 vs 25.48+/-1.30 (t =5.89, P<0.01) were also observed. With light microscope and electron microscope, the histopathology and ultra-microstructure of neuron and glial cell in the hippocampus tissue were changed.</p><p><b>CONCLUSION</b>The impairment of hippocampus of rabbits in juvenile stage with chronic moderate lead poisoning were observed, and the histopathology and N-methyl-D-aspartate receptor protein expressions in the hippocampus tissue were changed.</p>

Development and psychometric properties of the Chinese version of Children's Sleep Habits Questionnaire / 中华儿科杂志

<p><b>OBJECTIVE</b>To develop the Chinese version of Children's Sleep Habits Questionnaire (CSHQ) by translating and retranslating the English version of CSHQ and to examine the reliability, content validity, construct validity of the Chinese version in a general population of school-age children.</p><p><b>METHODS</b>During November and December 2005, a total of 20 457 school-age children from 55 primary schools of 9 cities were recruited through cluster-stratified selection, using geographic location, economic standard, and population density as criteria. A parent-administered questionnaire and the Chinese version of CSHQ were completed to quantify sociodemographic characteristics and to characterize sleep patterns and sleep disturbances, respectively.</p><p><b>RESULTS</b>The internal consistency of overall questionnaire and the eight subscales of the Chinese version of CSHQ was good (Cronbach's alpha coefficient was 0.73 and ranged from 0.42 to 0.69, respectively). The consistency between mother and father was ICCs = 0.89 for overall questionnaire and ranged from ICCs = 0.83 to ICCs = 0.92 for subscales. The test-retest reliability was ICCs = 0.85 for overall questionnaire and range from ICCs = 0.60 to ICCs = 0.88 for subscales. Factor analysis revealed a three-factor structure, which could represent bedtime behavior problems, sleep disturbance, sleep duration and daytime sleepiness, respectively, and the three factors could be used to explain 58.63% of the total variance. The factor loading was above 0.5 for the corresponding subscale.</p><p><b>CONCLUSIONS</b>Reliability, content validity and construct validity of the Chinese version of CSHQ in a general population of school-age children are good. It appears to be a suitable instrument for measuring sleep patterns and screening for sleep problems in school-aged children.</p>

Association between vitamin D receptor gene polymorphism and vitamin D deficiency rickets / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To explore the genetic susceptibility of children to vitamin D deficiency rickets through studying the association between Vitamin D receptor (VDR) gene polymorphism and vitamin D deficiency rickets.</p><p><b>METHODS</b>One hundred and fifty-nine children (100 boys and 59 girls, aged 0 to 2 years), with new-onset vitamin D deficiency rickets were enrolled. The patients sampled from a community of Jiamusi City, Heilongjiang Province. Seventy-eight healthy age-matched children (46 boys and 32 girls) were used as the controls. VDR gene polymorphism (cleaved by restriction endonuclease Fok I) was analyzed by polymerase chase reaction-restriction fragment length polymorphism (PCR-RFLP). The frequencies of the VDR genotype and allele were compared between the two groups.</p><p><b>RESULTS</b>The frequencies of FF, Ff and ff genotypes were 37%, 51% and 12% in the Rickets group, and 18%, 55% and 27% in the Control group. A significant difference was found in the frequency distribution of the VDR genotype between the two groups (chi(2)(0.01(2))=9.210, chi(2)=13.3880, P < 0.01). In the Rickets group, f allele frequency was lower (37% vs 54%), while the F allele was more common than the Control group (63% vs 46%).</p><p><b>CONCLUSIONS</b>There is an association between the VDR gene Fok I polymorphism and vitamin D deficiency rickets. The individuals with the F allele are more susceptible to vitamin D deficiency rickets.</p>

Establishment of Animal Model for Study of Children with Moderate Blood Lead Levels with Young Rabbits / 实用儿科临床杂志

Objective To establish the animal model for the study of children with moderate blood lead levels in young rabbits,for the study of the ideal therapy for moderate lead poisoning in children.Methods Sixteen 45-day-old male New Zealand rabbits were randomly divided into control and lead-exposed group,8 in each group.Rabbits in the lead-exposed group were treated with 5 mg/(kg?d)lead acetate in their forage for 6 weeks to establish moderate lead poisoning animal model.The blood lead levels(BLLs)were determined by atomic absorption spectrometer(AAS),and the urine lead levels and the lead concentrations of tissue and organ were determined by inductively coupled plasma-mass spectrometry(ICP-MS).Histopathology in tissue and organ was observed under the light microscope.Results The BLLs and the urine lead levels in lead-exposed group step up rapidly in primal weeks,then retained at a steady levels.The BLLs exhibited moderate level BLLs during the lead exposure period.Compared with control group,the body weight gain,testis and hippocampus wet coefficient of the lead-exposed group significantly decreased(P_a

Parental education to reduce blood lead levels in children with mild and moderate lead poisoning: a randomized controlled study / 中华儿科杂志

<p><b>OBJECTIVE</b>To evaluate the effectiveness of parental education on reducing lead exposure of children by examining the changes in blood lead levels of children whose parents receiving or not receiving educational intervention.</p><p><b>METHODS</b>Two hundred children with confirmed blood lead levels beyond 100 microg/L were selected. They were randomized into two groups, 107 children in study group and 93 in control. At the beginning of the study, parents of both study and control groups were called for interview to complete KABP questionnaire and lead study questionnaire. The study group was provided with interventional measures while control group was not contacted until the end of study. Intervention of parental education was undertaken by means of a TV program, a set of slides and a brochure, and focused on the questions regarding harmful effects of lead poisoning, the sources of environmental lead and prevention of this preventable disease. Tests for blood lead level were repeated for both study and control groups 3 months after the determination of the initial blood lead level.</p><p><b>RESULTS</b>All the relevant knowledge of health effect, lead sources and prevention of childhood lead poisoning of participating parents of study group were improved significantly (chi(2) = 14.06, 13.07, 10.08, 28.26, P < 0.01) after educational intervention while parents control group also were significantly improved in the sub-catalogs of concept and prevention (chi(2) = 7.69, 8.64, P < 0.01), but not the health effect and sources of childhood lead poisoning. Children and parents' behavior in study group was improved accordingly and significantly. Less children ate popcorn (chi(2) = 4.08, P < 0.05), less children drank tap-water in the morning (chi(2) = 23.04, P < 0.01), more kids washed their hands before eating (chi(2) = 5.82, P < 0.05), less kids played on road side (chi(2) = 9.60, P < 0.01), and more parents changed their coat or took shower or washed hands before going home after work (chi(2) = 4.00, P < 0.05). But in the control group only the number of kids playing on road side was decreased significantly (chi(2) = 9.60, P < 0.01). A general decline in blood lead levels was detected in both groups with statistical significance at P < 0.01. However, the decrease in blood lead levels was more remarkable in the study group. There was average reduction of 55 microg/L (35%) in blood lead levels for study group (t = 4.979, P < 0.01) and an almost 33 microg/L (20%) for control (t = 3.398, P < 0.01). The reduction in blood lead level was 22 microg/L greater in study group (t = 3.531, P < 0.01). The study also showed that the effectiveness of the educational interventions depended upon various aspects. Fourteen variables were included in the stepwise multiple regression equation of blood lead level changes. Such as parents' occupational exposure to lead, the improvement of knowledge about prevention of childhood lead poisoning, the chang of habit of snacks intake, parents' education levels, the change of attitude of parents for the childhood lead poisoning, etc.</p><p><b>CONCLUSION</b>Educating parents is proved to be an effective approach for children with mild and moderate lead poisoning.</p>

The parents' opinions on screening program regarding newborn hearing / 中华流行病学杂志

<p><b>OBJECTIVE</b>To investigate opinions on screening of newborn hearing from parent's and its influence to parents and their families.</p><p><b>METHODS</b>Parents were divided into two groups and were given the same questionnaire. Those parents whose babies had passed the first test were in the first group, and those parents whose babies failed the test were in the second group.</p><p><b>RESULTS</b>Most of the parents showed their ignorance to hearing screening with about 97.5% of parents admitted they had little knowledge of hearing screening. 93.06% of the parents showed positive attitude to the screening after being informed of the test. 59.73% of the parents thought the test results were reliable. 73.12% of the parents whose babies showed negative result at the first-test, thought the results were accurate. There were only 38.19% of the parents whose babies failed the first test held the same opinion. We also found that there were some disagreement among 78% of the parents who believed that the positive screening results might cause additional psychological stress on them and therefore affecting their normal family life.</p><p><b>CONCLUSIONS</b>Being informed of the screening, parents showed awareness of the test and were willing to cooperate. They believed the test was beneficial to their babies. Some parents whose babies did not pass the first screening test were often doubtful to the results and refused to be followed up. Therefore, we should improve our diagnostic technology to reduce the negative effects of the test. The results of our investigation suggested that the newborn hearing screening was applicable in our country.</p>

An epidemiological study on sleep problems in children aged 1 to 23 months in Shanghai / 中华预防医学杂志

<p><b>OBJECTIVE</b>To understand prevalence of sleep problems and presence of improper sleep habit of children aged one to 23 months in Shanghai, and to identify their related factors.</p><p><b>METHODS</b>Totally, 1 252 normal children, without severe illness and abnormal delivery history, aged one to 23 months were randomly selected from five districts of Shanghai. Under strict quality control system, their parents were interviewed with questionnaire to look into their familial and social environment, as well as sleep-related factors.</p><p><b>RESULTS</b>Fully-completed information was obtained in 1 129 of 1 252 children, with a response rate of 90.18%. Prevalence of sleep problems in children was 65.90% in Shanghai, remarkably higher than in the other areas. Prevalence of nightmare, level of fright at night, snore and sleep apnea in boys were significantly higher than those in girls. Prevalence of improper sleep habit in children was also higher, including sleeping with their parents, parental presence at sleep onset and irregular sleep time. Main risk factors related to children's sleep problems were maternal anxiety, children's irregular sleep time, parental presence at sleep onset, difficulty-type temperament and maternal poor sleep during pregnancy.</p><p><b>CONCLUSIONS</b>In Shanghai, prevalence of sleep problems in children aged one to 23 months was relatively higher and main risk factors for them were social, cultural and familial environment, especially negligence of cultivating proper sleep habit and parental improper response to children's poor sleep behavior.</p>