[Risk factors for iron deficiency anemia in infants aged 6 to 12 months and its effects on neuropsychological development].

OBJECTIVE: To study the risk factors for moderate and severe iron deficiency anemia (IDA) in infants aged 6-12 months, and to preliminarily investigate the effects of IDA on the neuromotor development and temperament characteristics of infants. METHODS: A total of 326 infants aged 6-12 months with IDA were classified into three groups: mild IDA (n=176), moderate IDA (n=111), and severe IDA (n=39) according to the severity of anemia. The risk factors for moderate or severe IDA were investigated by multivariate logistic regression analysis. Three hundred and forty-six infants without IDA who showed matched age, sex, and other backgrounds were selected as the control group. The Gesell Development Diagnosis Scale was used to evaluate children's mental development. The Temperament Scale for infants was used for evaluating children's temperament. RESULTS: The univariate analysis showed that the severity of IDA was associated with sex, birth weight, gestational age, multiple birth, maternal anemia during pregnancy, and mother's lack of knowledge about IDA (P<0.05). Setting the mild IDA group as control, the multivariate logistic regression analysis showed that multiple birth, premature birth, low birth weight (<2500 g), maternal anemia during pregnancy, breast feeding, and mother's lack of knowledge about IDA were the risk factors for severe IDA (OR>1; P<0.05); premature birth, breast feeding, and mixed feeding were the risk factors for moderate IDA (OR>1; P<0.05). The IDA group had significantly lower scores in Gesell general development quotient, gross motor, adaptive behavior, and fine motor than the control group (P<0.05). The IDA group had higher percentages of children with difficulty and intermediate difficulty temperaments than the control group (P<0.05). The IDA group had significantly higher scores in activity level, rhythmicity, adaptability, and perseverance than the control group (P<0.05). CONCLUSIONS: The severity of IDA is associated with premature birth, multiple birth, low birth weight, feeding pattern, maternal anemia during pregnancy and mother's lack of knowledge about IDA in infants aged 6-12 months. Infants with IDA have delayed neuromotor development and most of them have negative temperaments. More attention should be paid to mental and behavior problems for the infants. It is necessary to provide guidance for their parents in feeding and education.

DNA hypermethylation and X chromosome inactivation are major determinants of phenotypic variation in women heterozygous for G6PD mutations.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked incompletely dominant enzyme deficiency that results from G6PD gene mutations. Women heterozygous for G6PD mutations exhibit variation in the loss of enzyme activity but the cause of this phenotypic variation is unclear. We determined DNA methylation and X-inactivation patterns in 71 G6PD-deficient female heterozygotes and 68 G6PD non-deficient controls with the same missense mutations (G6PD Canton c.1376G>T or Kaiping c.1388G>A) to correlate determinants with variable phenotypes. Specific CpG methylations within the G6PD promoter were significantly higher in G6PD-deficient heterozygotes than in controls. Preferential X-inactivation of the G6PD wild-type allele was determined in heterozygotes. The incidence of preferential X-inactivation was 86.2% in the deficient heterozygote group and 31.7% in the non-deficient heterozygote group. A significant negative correlation was observed between X-inactivation ratios of the wild-type allele and G6PD/6-phosphogluconate dehydrogenase (6PGD) ratios in heterozygous G6PD Canton (r=-0.657, p<0.001) or Kaiping (r=-0.668, p<0.001). Multivariate logistic regression indicated that heterozygotes with hypermethylation of specific CpG sites in the G6PD promoter and preferential X-inactivation of the wild-type allele were at risk of enzyme deficiency.

[Relationship between G6PD deficiency and hand-foot-mouth disease induced by enterovirus 71].

OBJECTIVE: To study the influence of glucose-6-phosphate dehydrogenase (G6PD) deficiency on hand-foot-mouth disease (HFMD) induced by enterovirus 71 (EV71) , and possible mechanisms. METHODS: A total of 220 boys with HFMD induced by EV71 were classified into two groups based on disease severity: mild/moderate (n=145) and severe HFMD groups (n=75), and 132 healthy boys were selected as the control group. The activity of G6PD and levels of reduced glutathione (GSH) and malonaldehyde (MDA) in blood were measured using the automatic biochemical analyzer. RESULTS: The percentage of G6PD deficiency cases in the severe HFMD group was significantly higher than in the control group (P<0.0125). In the severe HFMD group, the durations of fever, mental abnormality, limb trembling and hospital stay were significantly longer in children with G6PD deficiency than in those with normal G6PD activity (P<0.05). In the acute and recovery stages, patients in the mild/moderate and severe HFMD groups had significantly lower GSH levels and G6PD activity and significantly higher MDA levels compared with those in the control group (P<0.05). In the acute stage, children in the mild/moderate and severe HFMD groups with G6PD deficiency had significantly lower GSH levels and significantly higher MDA levels compared with those with normal G6PD activity (P<0.01). In the acute and recovery stages, GSH level in children with HFMD was positively correlated with G6PD activity (r=0.61, P<0.01; r=0.58, P<0.01), and in the acute stage, MDA level was negatively correlated with G6PD activity (r=-0.29, P<0.01). CONCLUSIONS: G6PD deficiency is probably a predisposing factor for HFMD induced by EV71 and may aggravate the patient's condition. Its mechanism might be related to oxidative stress.

Reliable detection of paternal SNPs within deletion breakpoints for non-invasive prenatal exclusion of homozygous α-thalassemia in maternal plasma.

Reliable detection of large deletions from cell-free fetal DNA (cffDNA) in maternal plasma is challenging, especially when both parents have the same deletion owing to a lack of specific markers for fetal genotyping. In order to evaluate the efficacy of a non-invasive prenatal diagnosis (NIPD) test to exclude α-thalassemia major that uses SNPs linked to the normal paternal α-globin allele, we established a novel protocol to reliably detect paternal SNPs within the (--(SEA)) breakpoints and performed evaluation of the diagnostic potential of the protocol in a total of 67 pregnancies, in whom plasma samples were collected prior to invasive obstetrics procedures in southern China. A group of nine SNPs identified within the deletion breakpoints were scanned to select the informative SNPs in each of the 67 couples DNA by multiplex PCR based mini-sequencing technique. The paternally inherited SNP allele from cffDNA was detected by allele specific real-time PCR. A protocol for reliable detection of paternal SNPs within the (--(SEA)) breakpoints was established and evaluation of the diagnostic potential of the protocol was performed in a total of 67 pregnancies. In 97% of the couples one or more different SNPs within the deletion breakpoint occurred between paternal and maternal alleles. Homozygosity for the (--(SEA)) deletion was accurately excluded in 33 out of 67 (49.3%, 95% CI, 25.4-78.6%) pregnancies through the implementation of the protocol. Protocol was completely concordant with the traditional reference methods, except for two cases that exhibited uncertain results due to sample hemolysis. This method could be used as a routine NIPD test to exclude gross fetal deletions in α-thalassemia major, and could further be employed to test for other diseases due to gene deletion.

Molecular epidemiology investigation of beta-thalassemia in Zhongshan City, Guangdong Province, People's Republic of China.

Beta-THAlassemia (beta-thal) is one of the most common genetic diseases in southern China. In order to obtain detailed epidemiology data to be used for primary prevention programs, we have analyzed 2,055 independent subjects living in Zhongshan City, Guangdong Province, People's Republic of China (P.R. China), by using hematological biochemical screening and DNA technology. The results indicate a higher prevalence (3.07%) of beta-thal and coinheritance of alpha- and beta-thal (0.49%) than previously reported for Guandong Province. Ten beta-thal mutations were found in 63 independent chromosomes. The four most common mutations [codons 41/42 (-TCTT), IVS-II-654 (C>T), -28 (A>G), codon 17 (A>T)] accounted for 90.46% of the total. The uncommon mutations profile was different from that of other cities in Guangdong Province and the rare mutation IVS-II-2 (-T), once reported in Hong Kong, was also detected. This study will contribute to the development of prevention strategies in the region, allowing better genetic counseling and prenatal diagnosis of beta-thal.

[Matrine-induced erythroid differentiation of K562 cells is associated with activation of the apoptotic pathway].

OBJECTIVE: To observe matrine-induced erythroid differentiation of K562 cells in relation to activation of the apoptotic pathway in vitro. METHODS: K562 cells were cultured in the presence or absence of matrine at different concentrations for 4 days, and the morphological and ultramicrostructural changes of the cells were observed using inverted microscopy and transmission electron microscopy, respectively. The expression of apoptosis-related protein p27kip1 was detected by immunocytochemistry. RESULTS: Compared to untreated K562 cells, the cells treated with matrine at 0.10 g/L exhibited apoptostic characteristics in the cellular morphology and ultramicrostructure, with the expression of p27kip1 protein upregulated in a concentration- and time-dependent manner. CONCLUSION: Matrine-induced erythroid differentiation of K562 cells is associated with cell apoptosis, and upregulation of p27kip1 protein expression may play a crucial role in the process of apoptosis.

[Matrine-induced gamma-globin synthesis in K562 cells].

OBJECTIVE: To study the effects of matrine on gamma-globin synthesis in K562 cells in vitro. METHODS: Benzidine staining was used to study the dose- and time-dependent effects of matrine on hemoglobin synthesis in K562 cells, and Western blotting was performed to determine the level of hemoglobin F(alpha(2)gamma(2)). RESULTS: Benzidine staining showed that K562 cells treated with matrine of 0.1 mg/ml had a positivity rate for benzidine (BZ%) of 15.67% at 96 h after the treatment, and Western blotting indicated increased synthesis of hemoglobin F. CONCLUSION: Matrine can induce gamma-globin synthesis and increase hemoglobin F level in K562 cells, the effect of which resembles that of sodium butyrate.