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Follicular helper T (Tfh) cells and follicular regulatory T (Tfr) cells are critical for the development and maintenance of germinal centre (GC) and humoral immune responses. Accumulating evidence has demonstrated that the dysregulation of either Tfh cells or Tfr cells contributes to the pathogenesis of autoimmune diseases. We aim to investigate the roles of circulating Tfh cells and circulating Tfr cells in the pathogenesis of primary biliary cholangitis (PBC). A total of 34 patients with PBC and 27 health individuals were enrolled in this study. Flow cytometry revealed that circulating Tfh (CD4+ CXCR5+ CD127hi CD25lo ) cells were increased, but Tfr (CD4+ CXCR5+ CD127lo CD25hi ) cells and ratio of Tfr/Tfh were dramatically decreased in PBC patients compared with healthy controls. The Tfr/Tfh ratio was negatively correlated with level of serum IgM. Meanwhile, we also observed effector memory (CCR7lo PD-1hi ) Tfh cells and Tfr cells were dramatically increased, but central memory (CCR7hi PD-1lo ) Tfh cells and Tfr cells were decreased in PBC patients compared with healthy controls. Effector memory Tfr cells were positively correlated with level of serum ALP. These results indicate that an imbalance of circulating Tfr cells and Tfh cells may be involved in the immunopathogenesis of PBC and may provide novel insight for the development of PBC therapies.

The aim of this study is to describe the prevalence of hypospadias and its time trends during 1993-2005 in southeast China, and to explore the potential risk factors.The study population included all male live and still births (at least 20 weeks of gestation) in 11 cities and counties in Jiangsu and Zhejiang Provinces in Southeast China born during January 1, 1993, through December 31, 2005.Overall prevalence of hypospadias was 5.8 per 10,000 male births and presented an increasing trend during 1993-2005 (with chi(for trend) (2) of 3.94, p = 0.047). Prevalence of coronal hypospadias and those with unknown sites increased from 1.7 and 0.3 per 10,000 male births in 1993 to 3.6 and 1.4 per 10,000 male births in 2005, respectively (with chi(for trend) (2) of 7.29 and 9.05, p = 0.007 and p = 0.002, respectively), but prevalence of perineal hypospadias decreased (with chi(for trend) (2) of 7.13, p = 0.008). Maternal fever during first trimester, birth of twins or more children, and year of birth were independent risk factors for hypospadias, with odds ratios of 4.14 (95% CI, 1.32-12.83), 3.37 (95% CI, 1.73-6.58), and 1.04 (95% CI, 1.00-1.08), respectively, after adjusting for confounding factors with multivariable logistic regression analysis.Prevalence of hypospadias increased during 1993-2005 in the two provinces in southeast China. Maternal fever in the first trimester and birth of twins or more children are associated with the risk for hypospadias.

MgH2 nanoparticles were obtained by hydriding ultrafine magnesium particles which were prepared by hydrogen plasma–metal reaction. The X-ray diffraction (XRD) and transmission electron microscopy (TEM) results show that the obtained sample is almost pure MgH2 phase, without residual magnesium and with an average particle size of ∼300 nm. Milled with 5 wt.% TiF3 as a doping precursor in a hydrogen atmosphere, the sample desorbed 4.5 wt.% hydrogen in 6 min under an initial hydrogen pressure of ∼0.001 bar at 573 K and absorbed 4.2 wt.% hydrogen in 1 min under ∼20 bar hydrogen at room temperature. Compared with MgH2 micrometer particles doped with 5 wt.% TiF3 under the same conditions as the MgH2 nanoparticles, it is suggested that decrease of particle size is beneficial for enhancing absorption capacity at low temperatures, but has no effect on desorption. In addition, the catalyst was mainly responsible for improving the sorption kinetics and its catalytic mechanism is discussed.

BACKGROUND: In the past, northern China’s Shanxi Province has reported the highest incidence of neural tube defects (NTDs) in the world. However, little is known about the epidemiology of NTDs in this area in recent years. METHODS: Data were collected from a population-based birth defects surveillance system in 4 counties that captures information on all live births, stillbirths of at least 20 weeks’ gestation, and pregnancy terminations at any gestational age resulting from prenatal diagnosis of a birth defect. We also surveyed mothers of NTD case patients to determine their use of folic acid before and during early pregnancy. RESULTS: During 2003, 160 NTD cases were identified among 11,534 births (NTD birth prevalence 138.7/10,000 births). The rates of anencephaly, spina bifida and encephalocele were 65.9, 58.1, and 14.7 per 10,000, respectively, and a female predominance was observed among anencephaly cases (male-to-female relative risk [RR], 0.49; 95% confidence interval [CI], 0.30 – 0.79), but not among spina bifida (RR, 0.90; 95% CI, 0.55–1.45) and encephalocele (RR, 1.03; 95% CI, 0.40 –2.69) cases. The percentages of pregnancy termination following prenatal diagnosis of anencephaly, spina bifida, and encephalocele were 50%, 41.8%, and 35.3%, respectively. NTD birth prevalence tended to be higher among mothers aged 20 or 30 years (P .06) and was markedly associated with lower levels of maternal education (P .001). Among 143 NTD mothers, only 6 (4.2%) used folic acid supplements during the periconceptional period. CONCLUSIONS: The NTD birth prevalence rate in the study area is among the highest worldwide. Folic acid deficiency may be one important risk factor. Birth Defects Research (Part A) 76:237–240, 2006. © 2006 Wiley-Liss, Inc.

The purpose of this study was to evaluate the effect of hemoglobin (Hb) level during early gestation on the cognitive development of children at 4 - 6 years of age.A total number of 3609 children were randomly selected from all the live birth infants whose mothers participated in a community intervention trial during 1993 - 1996 in 13 counties or cities in Jiangsu and Zhejiang provinces. Hb concentration during early gestation was measured at first prenatal examination and intelligence quotients (IQ), including full-scale, verbal and performance were assessed using Chinese-Wechsler Intelligence Scale for Children in 2000 - 2001 when these children had a mean age of 68 months.Compared with children whose mothers were non-anemic during early gestation, children whose mothers were anemic had a 0.6 point higher mean verbal scale IQ, a 0.9 point higher mean performance IQ and a 0.8 point higher mean full-scale IQ. These differences were not statistically significant when children's gender, age at intelligence test, region, parity and mother's IQ, education level and occupation were adjusted for. When mother-child pairs were divided into 5 sub-groups of every 20 percentiles according to Hb concentration during early gestation, verbal IQ scores of the lowest (Hb103 g/L), the moderate (110 g/L ≤ Hb116 g/L) and the highest Hb concentration group (Hb ≥ 124 g/L) were 91.6 ± 18.9, 92.8 ± 18.2 and 90.3 ± 18.6, respectively. The performance IQ scores were 104.7 ± 15.2, 104.5 ± 14.3 and 103.5 ± 15.1, and full-scale IQ scores were 97.8 ± 17.3, 98.4 ± 16.3 and 96.4 ± 17.4, respectively. After controlling for confounding factors, children whose mothers had highest Hb concentration were 54% (OR = 1.54, 95%CI: 1.13 - 2.11) more likely to have poor verbal scores and 53% (OR = 1.53, 95%CI: 1.10 - 2.12) more likely to have poor full-scale scores than children whose mothers had moderate Hb concentration. No statistical associations were noticed between high Hb concentration and performance scores, or between low Hb concentration during early gestation and verbal, performance as well as full-scale score of pre-school children.High maternal Hb concentration during early gestation might adversely affect children's cognitive development.

To analyze the influencing factors for stunting and underweight among children aged 3 - 6 years in 15 counties of Jiangsu and Zhejiang provinces so as to provide reference for enhancing growth level among preschool children.Data was from the 183 295 records of Children Follow-up Study Project carried out by the Institute of Reproductive and Child Heath of Peking University and the records of related perinatal health care surveillance system in rural areas of 15 counties/cities of Jiangsu and Zhejiang provinces. WHO-NCHS standard was used to assess the childhood physical level of growth. Data of children's birth and their mothers' perinatal health were correlated to determine influencing factors for childhood stunting and underweight.The average stunting rate was 7.95% and underweight rate was 1.55%. Sex, birth weight, preterm birth as well as maternal height, maternal BMI at the first prenatal visit, maternal education and occupation were significantly related to childhood stunting and underweight. Birth weight was the most important influencing factor for childhood underweight. For the groups whose birth weights were2500 g and ≥ 2500 g, the rates of underweight were 7.77% and 1.46% respectively. Children with low birth weight were at higher risk for underweight (OR = 3.68, 95%CI: 3.11 - 4.37). Maternal height was the most important influencing factor for childhood stunting. For the groups whose mothers' heights were155 cm, 155 - 160 cm, 160 - 165 cm and ≥ 165 cm, the stunting rates were 13.01%, 8.76%, 6.21% and 4.14% respectively. Compared with the ≥ 165 cm group, the155 cm group was at higher risk for stunting (OR = 3.08, 95%CI: 2.82 - 3.37).Birth weight and maternal height were key factors influencing the growth of children. Perinatal health care and the nutrition status of pregnant mothers should be improved to promote the growth level of preschool children.

Our purpose was to evaluate the association between hemoglobin concentration (Hb) and cognitive ability of children at 4 - 6 years of age in 21 counties/cities in China.A total number of 7331 children born during 1993 - 1996 were randomly selected from 21 counties or cities in Hebei, Jiangsu and Zhejiang provinces. Hb concentration of children were measured followed by three tests including full-scale, verbal and performance intelligence quotient (IQ) test performed by Chinese-Wechsler Intelligence Scale for Children, one year later.There were a 0.7 point difference in mean verbal scale IQ (P = 0.144) and a 0.9 point difference in both mean performance and full-scale IQ (P = 0.055 and 0.079, respectively) between anemia and non-anemia groups. Compared with children with non-anemia, children with anemia were 1.3-fold more likely to score poorly in verbal IQ and operational IQ (95%CI: 1.1 - 1.6, 1.1 - 1.5, respectively) and 1.4-fold more likely to have had poor scores in full-scale IQ (95%CI: 1.2 - 1.6) after controlled for children's gender, age at intelligence test, region, parity and mother's IQ, education level, occupation. Participants were divided into 5 sub-groups according to Hb concentration of every 20 percentile. Verbal IQ scores of the lowest (Hb110 g/L), moderate (117 g/L/= Hb122 g/L) and the highest Hb concentration groups (Hb/= 130 g/L) were 90.6 +/- 18.1, 94.0 +/- 17.6 and 91.0 +/- 16.4, respectively. Performance IQ scores were 102.2 +/- 15.7, 104.6 +/- 14.8 and 100.5 +/- 14.9, respectively. Full-scale IQ scores were 95.9 +/- 17.3, 99.0 +/- 16.4 and 95.2 +/- 15.6, respectively. Children with both low and high hemoglobin levels did poorly in all intelligence tests than children with moderate Hb concentration (P0.001). After controlling for confounding factors, children with the lowest concentration were 1.4-fold more likely to have had poor verbal and performance scores than children with moderate Hb concentration (95%CI: 1.1 - 1.7, 1.1 - 1.8, respectively) and 1.5-fold (95%CI: 1.2 - 1.8) more likely to have had poor full-scale scores than those with moderate Hb concentration. The association between high Hb concentration and low IQ scores disappeared in the multivariate model.Low Hb concentration might have adversely affected children's cognitive development.

To examine the association between pregnancy-induced hypertension (PIH) and small-for-gestational-age babies (SGA) in a Chinese population.Subjects were women who delivered a singleton baby (gestational weeks: equal to or greater than 28, and less than 42) in four cities or counties in Jiangsu and Zhejiang provinces, China, during the period of 1995 - 2000. A total number of 93 743 women were included. Incidence of SGA was calculated and compared between women with or without PIH and between groups with different severities of PIH. Multiple logistic regression was used to address the relationship between PIH and SGA while controlling for maternal age, occupation, education, parity, BMI, anemia, premature rupture of membranes and fetal sex. The association between PIH and SGA was also examined according to preterm or term delivery.The incidence of SGA in women with PIH (6.0%) was higher than women without (4.5%), and the incidence increased with severities of PIH. The adjusted relative risk rates (95% CI) of SGA in women with mild,moderate and severe PIH were 1.17 (1.01-1.34), 1.69 (1.33-2.14), and 3.50 (2.57-4.77), respectively, when confounders were controlled for. The risk ratios of SGA in women with PIH among women who delivered a preterm baby were higher than those among women who delivered a term baby.There seemed a statistical association between PIH and SGA and women with PIH having higher incidence of SGA than those without PIH.

To describe the prevalence of anemia and yearly trends (1993-2003) among women who came to the hospitals or maternal and child health units for premarital examinations in 6 counties of Jiangsu and Zhejiang provinces.Data were obtained from the records of the premarital examinations in perinatal health care surveillance system that had been established since 1992 in these areas. We reviewed hemoglobin levels of those women who were enrolled in the perinatal health care surveillance system from 1993 to 2003. Anemia was defined according to the WHO (2001) criterion. We calculated the prevalence of anemia and analyzed the yearly trends based on the data of hemoglobin concentration.In the period of 1993-2003, there were 82 995 anemia cases identified among 193,434 women with an overall anemia rate as 42.9%. The rates of anemia were high (65.5%) in 1993 but low (25.8%) in 2003. 99.7% of the anemic women whose hemoglobin concentration were between 80-119.9 g/L. Time trend analysis indicated a significant decline on anemia rate while monthly analysis showed that the prevalence rates were high (48.2%) in September and low in March (39.5%). The results also showed that the prevalence rates of anemia were relatively higher in farmers and workers in rural enterprises, and lower in Han ethnicity than minorities. The higher prevalence rates of anemia were presented among the women with less education, lower body mass index, or at older age.For those premarital women in 6 counties of Jiangsu and Zhejiang provinces, the overall anemic rate presented a significant downward trend between 1993 and 2003 while the prevalence of anemia remained high, especially for the women with less education, lower body mass index or older ages.

To investigate the association between third trimester hemoglobin (Hb) concentrations and the risk of low birth weight and preterm delivery in a Chinese population.Subjects were women who delivered in four cities/counties in Jiangsu and Zhejiang provinces, China, during the period of 1995 - 2000. Incidence of low birth weight and preterm delivery was calculated and compared among groups of women with different levels of Hb during the third trimester. Multiple logistic regression was used to address relationships between Hb levels and the risk of preterm delivery and low birth weight while controlling for potential confounding factors.The overall prevalence of anemia during third trimester of pregnancy was 48.2% , mainly consisting of mild and moderate anemia. Mild and moderate anemia did not increase the risk of preterm delivery and low birth weight statistically. The lowest incidence of preterm delivery and low birth weight was found among pregnant women with Hb levels at 90-99 g/L. The risk for preterm delivery and low birth weight increased with either increasing or decreasing hemoglobin concentrations. However,there was no remarkable elevation of the risk when Hb was in the range of 70-119 g/L. Women with severe anemia (Hb70 g/L) had 80% higher risk (95% CI:1.0-3.3) of preterm delivery and a 4.0-fold higher risk (95 % CI :2. 1-7.5) of low birth weight compared with women with an Hb value of 90-99 g/L. In addition, women with a high Hb concentration (Hb130 g/L) had 20% higher risk (95 % CI: 1..0-1.4) of preterm delivery and 50 % higher risk (95 % CI: 1.2-1.9) of low birth weight.A U-shape relationship was found between Hb concentration and the risk of preterm delivery and low birth weight. Severe anemia and high hemoglobin concentration were both associated with increased risk of preterm deliveries and low birth weight.

To describe the epidemiological characters of pregnancy-induced hypertension (PIH) in Jiaxing areas of Zhejiang province of China between 1995 and 2000.We analyzed the perinatal health surveillance data that was collected as part of the Sino-American cooperative project on neural tube defects prevention established in 1992. The study population consisted of 136 070 pregnant women with at least 20 weeks of gestational age. National diagnostic criteria were used to identify the cases which were divided into three subgroups: mild, moderate and severe.15 127 cases were identified and the overall incidence rate of PIH was 11.1% (95% CI : 11.0% - 11.3%). Among all the cases, mild, moderate and severe PIH were accounted for 71.4%, 22.3% and 6.3%, respectively. The proportions of PIH cases that occurred in the second trimester, third trimester and during delivery appeared to be 4.2%, 34.4% and 61.4%, respectively. There was a significant fall in the trend of PIH occurrence every year, which dropped from 10.7% in 1995 to 8.6% in 2000 by 19.6%. More risk of PIH seemed to be related to those mothers living in the urban areas with age under 20 or above 35, being peasants and having little educational, having had multiple gestations, conceiving in spring/summer or delivering in winter or spring etc. Compared with the results of national survey in 1988, the incidence rate of PIH was higher by 18.1%, while the proportion of severe PIH was much lower by 68.8%. Although the incidence rates of PIH in urban and rural areas were somehow similar, the proportion of severe PIH in rural areas was much higher than that in urban areas.Overall incidence rate and distribution of PIH were reported. Compared with the results in 1988, incidence rate of PIH was much higher, particularly for mild cases.

To compare two methods (microbial assay and radioimmunoassay) for measuring plasma folate concentrations, and to examine the relationship between plasma folate levels, and alcohol consumption, tobacco use and body mass index, and the risk of hyperhomocysteinemia in China.We used a microtiter plate microbial assay and a radioimmunoassay to measure the folate concentration in 88 plasma samples. After comparing the results of these two methods and fitting a regression line, we examined the geographical, seasonal, and gender differences in folate concentration of plasma collected from 2,422 adults in south and north areas in China, and evaluated the association of plasma folate concentration, with alcohol consumption, cigarette smoking, and body mass index, and with the risk of hyperhomocysteinemia, using the data from the two assays.The data from the two assays had a linear relationship (r=0.879, P=0.000); the regression was Y=0.683X+0.308 (where X and Y were nature logarithmic transformations of plasma folate by microbial assay and radioimmunoassay, respectively); however, the mean plasma folate levels by microbial assay were much higher than those obtained by radioimmunoassay. Both data sets showed similar plasma folate distributions among Chinese adults, associations with other risk factors, and the risk of hyperhomocysteinemia. We estimated that 19.9% of the Southerners and 67.1% of the Northerners had plasma folate concentrations by radioimmunoassay lower than the 6.8 nmol/L used to define plasma folate deficiency.There is a linear relationship between plasma folate levels determined by microbial assay and radioimmunoassay, but because of the different levels obtained in the two assays, it is difficult to use the microbial assay results to evaluate folate status at this time. The use of 10.5 nmol/L as a cut-off for plasma folate deficiency by microbial assay needs further study.

To describe the epidemiology of neural tube defects (NTDs) in high- and low-prevalence areas of China.Birth defects surveillance data, collected from 1992 through 1994 was analyzed. These data were collected as part of the Sino-American cooperative project on NTDs prevention. We classified NTDs as anencephaly, encephalocele, high-level and low-level spina bifida (SB) according to location of the lesion (high vs low) and whether the defect was isolated or occurred in association with other birth defects. Rates were compared in the high-prevalence (North) region and the low-prevalence (South) region, after adjusted for classification, urban and rural, season and sex, and calculated the adjusted rate of NTDs.Among seven hundred and eighty-four NTDs cases in 326 874 recorded births (include in livebirth, stillbirth and fetal death with a gestational age of at least 20 weeks), the overall NTDs prevalence in the North was 5.57/1,000 births, and in the South was 0.88/1 000. There were also significant differences in the prevalence of anencephaly, encephalocele, high-level and low-level SB between North (0.97, 0.49, 2.75 and 1.11/1,000 birth) and South (0.36, 0.15, 0.21 and 0.14/1,000 birth) (P0.01), with adjusted prevalences in the North 3 - 7 times higher than those in the South. There were significant difference between urban (2.04) and rural areas (6.57/1,000 birth) in the North (P0.01), urban (0.52) and rural areas (0.95/1,000 birth) in the South (P0.05). Adjusted prevalence rates in the rural were 3 - 4 times higher than those of urban in the North and 1.6 - 1.9 times higher than in the South; The seasonal rate of high-level SB increased between September and November in the North (3.44/1,000 birth), while the seasonal rate of anencephaly decreased between September and November (0.18/1,000 birth) in the South. However there were no seasonal changes in other classified NTDs both in the South and North.The birth prevalence of NTDs in the North of China was the highest in the world. There were significant differences between the North and the South, urban and rural. There was seasonal change in high-level SB in the North, which was in accordance to the phenotype of NTDs. It was suggested that there might exist etiological heterogeneity among anecephalus, low- and high-level SB.

Summary Background Folic acid supplements are recommended for women of childbearing age to prevent neural tube defects in their offspring. Results of some studies, however, suggest an increase in multiple births associated with use of vitamin supplements that contain folic acid during pregnancy. Our aim was to assess this association. Methods We used data from a population-based cohort study from which we assessed the occurrence of multiple births in women (n=242 015) who had participated in a campaign to prevent neural tube defects with folic acid supplements (400 μg per day) in China. Folic acid use was ascertained before pregnancy outcome was known. We studied the relation between multiple births and any use of folic acid pills before or during early pregnancy; additionally, we investigated mechanisms by which folic acid could potentially affect the occurrence of multiple births by examining pill-taking at three time periods: before ovulation, around the time of fertilisation, and after conception. Findings 1496 (0·62%) multiple births occurred in a cohort of 242 015 women who had registered with the study between October, 1993, and September, 1995, and who had a pregnancy not affected by a birth defect; the rate of multiple births in women who did and did not take folic acid before or during early pregnancy was 0·59% and 0·65%, respectively (rate ratio 0·91; 95% CI 0·82–1·00). Interpretation Our findings suggest that consumption of folic acid supplements during pregnancy is not associated with an increased occurrence of multiple births.