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Aimin Chen

Publications and source records attributed to Aimin Chen.

14 recordsLinked to original sources
PubMed2006

Maternal IQ, child IQ, behavior, and achievement in urban 5-7 year olds.

In one study of children in 27 families with maternal retardation, those children with higher intelligence quotient (IQ) were more likely to have multiple behavior problems than those with lower IQ. If true, this result would affect clinical practice, but it has not been replicated. Because the setting of the initial observation is similar to the setting of childhood lead poisoning, we attempted a replication using data from the Treatment of Lead-Exposed Children (TLC) study, in which 780 children aged 12-33 mo with blood lead levels 20-44 microg/dL were randomized to either succimer treatment or placebo and then followed up to 5 y. Of 656 mothers of TLC children with IQ measured, 113 demonstrated mental retardation (IQ <70). Whether maternal IQ was <70 or >or=70, children with IQ >or=85 were rated more favorably on cognitive tests and behavioral questionnaires than children with IQ <85; these measures included Conners' Parent Rating Scale-Revised at age 5, the Developmental Neuropsychological Assessment at ages 5 and 7, and the Behavioral Assessment System for Children at age 7. Among children of mothers with IQ <70, those with IQ >or=85 did not show more severe clinical behavioral problems, nor were they more likely to show multiple behavior problems. Children with higher IQ have fewer behavior problems, irrespective of the mother's IQ. In the special setting of mothers with IQ <70, children with higher IQ are not at greater risk of behavior problems.

Achievement↗
PubMed2006

The effect of chelation on blood pressure in lead-exposed children: a randomized study.

Studies in children suggest a weak association between blood lead concentration and blood pressure. To understand this better, we tested the strength of the association in children with elevated blood lead concentrations and whether succimer chelation changed blood pressure as it did blood lead. In a randomized clinical trial of 780 children with blood lead concentrations of 20-44 microg/dL at 12-33 months of age, we compared the systolic and diastolic blood pressure in the succimer-treated group and placebo group for up to 5 years of follow-up. We also analyzed the relation of blood lead to blood pressure. Children in the succimer group had lower blood lead concentrations for 9-10 months during and after treatment, but their blood pressure did not differ from those in the placebo group during this period. During 1-5 years of follow-up, children in the succimer group had systolic blood pressure 1.09 (95% confidence interval, 0.27-1.90) mmHg higher than did untreated children in a model with repeated measurements, but the difference in diastolic blood pressure was not statistically significant. No association between blood lead and blood pressure was found. Overall, there is no association between blood lead and blood pressure in these children with moderately high lead exposure, nor does chelation with succimer change blood pressure.

Blood Pressure↗
PubMed2005

Maternal smoking during pregnancy in relation to child overweight: follow-up to age 8 years.

BACKGROUND: Data from several studies indicate that children of mothers who smoked during pregnancy may be at a risk of overweight compared with children of non-smoking mothers. The size of this relation, however, is unclear, as is the age at which it becomes detectable. METHODS: Prospective data for 34 866 children enrolled in the US Collaborative Perinatal Project were analysed to examine maternal pregnancy smoking in relation to weight, height, and body mass index (BMI) in offspring at ages 1, 3, 4, 7, and 8 years. RESULTS: Compared with offspring of non-smokers, children of smokers had (i) weight that was lower at birth but then quickly equalled or exceeded that of non-smokers, (ii) consistently decreased height, and (iii) increased risk of overweight, particularly in girls. For example, at age 7 years, the adjusted odds ratio of BMI>or=85th percentile in boys of mothers who smoked on an average>or=20 cigarettes per day while pregnant was 1.22 (95% confidence interval 1.03-1.46), and in girls it was 1.30 (1.08-1.56). CONCLUSIONS: In these data, maternal smoking during pregnancy was associated with a modest increase in risk of overweight in children before the age of 8 years.

Birth Weight↗
PubMed2005

DDT serum concentration and menstruation among young Chinese women.

High DDE and DDT concentrations were found to be associated with shortened menstrual cycle length in Laotian immigrants to the United States. We examined this issue in a sample of young Chinese women. A total of 60 women aged 20-24 years were enrolled in three maternal and child health clinics (20 from urban, 20 from suburban, 20 from rural) in Shanghai, China, and vicinity, in 1998. Of these women, 47 who did not use hormonal contraceptives and had valid menstrual cycle characteristics were included in the analysis for associations among serum DDE and DDT concentration and menstrual cycle length, duration of menses, and heaviness of menstrual flow. In univariate analysis, higher p,p'-DDE concentration was associated with longer menstrual cycle length (0.66 day per 10 microg/L, 95% confidence interval [CI]: 0.21, 1.11 day). With adjustment for age, body mass index, education, occupation, and resident location, the estimate was 0.42 day (95% CI: -0.35, 1.19 day). p,p'-DDE was not associated with duration of menses or heaviness of menstrual flow. Neither p,p'-DDT nor o,p'-DDT were associated with menstrual cycle length, duration of menses or heaviness of menstrual flow. The study largely suggests no association between DDE and DDT concentrations and menstrual cycle characteristics in young Chinese women, though the weak-to-no correlation of DDE with menstrual cycle length merits further study.

Adult↗
PubMed2005

IQ and blood lead from 2 to 7 years of age: are the effects in older children the residual of high blood lead concentrations in 2-year-olds?

Increases in peak blood lead concentrations, which occur at 18-30 months of age in the United States, are thought to result in lower IQ scores at 4-6 years of age, when IQ becomes stable and measurable. Data from a prospective study conducted in Boston suggested that blood lead concentrations at 2 years of age were more predictive of cognitive deficits in older children than were later blood lead concentrations or blood lead concentrations measured concurrently with IQ. Therefore, cross-sectional associations between blood lead and IQ in school-age children have been widely interpreted as the residual effects of higher blood lead concentrations at an earlier age or the tendency of less intelligent children to ingest more leaded dust or paint chips, rather than as a causal relationship in older children. Here we analyze data from a clinical trial in which children were treated for elevated blood lead concentrations (20-44 microg/dL) at about 2 years of age and followed until 7 years of age with serial IQ tests and measurements of blood lead. We found that cross-sectional associations increased in strength as the children became older, whereas the relation between baseline blood lead and IQ attenuated. Peak blood lead level thus does not fully account for the observed association in older children between their lower blood lead concentrations and IQ. The effect of concurrent blood level on IQ may therefore be greater than currently believed.

Age Factors↗
PubMed2005

[Osteomyocutaneous latissimus dorsi scapular combined flap with vascularized rib to repair the large defect of tibia].

OBJECTIVE: To design a combined flap of subscapular axis including vascularized lateral scapular, rib and latissimus dorsi to repair the large defect of tibia. METHODS: The patient was a 39-year-old man who got a posttraumatic 12 cm defect of tibia after primary debridement and external fixation because of open fracture 5 months ago. There was a 12 cm x 6 cm scar involved the proximal medial segment of tibia. After resection of scar and fibular tissue over the bone defect floor, a latissimus dorsi myocutaneous flap 14 cm x 5 cm pedicled with subscapular artery-thoracodorsal artery, a flap 12.5 cm on the outside of the scapular pedicled with thoracodorsal artery, and 6th rib flap 13 cm by serratus were prepared. The tibialis posterior and saphenous vein were used for anastomosis. A proximal anatomic plate was applied to the fixation of tibia. RESULTS: The compound flap survived the operation. The follow-up period was 2 years. Bone union occurred 6 months after operation. CONCLUSION: This combined flap is successful and can provide alternative to the resolution of large defect of tibia.

Adult↗
PubMed2004

Mifepristone-induced early abortion and outcome of subsequent wanted pregnancy.

Follow-up information on subsequent pregnancies after mifepristone (RU486)-induced abortion is scarce. The authors examined whether one mifepristone-induced first-trimester abortion affects the outcome of a subsequent wanted pregnancy. In a study conducted in 1998-2001 at antenatal clinics in Beijing, Chengdu, and Shanghai, China, the authors enrolled 4,925 women with no history of induced abortion, 4,931 women with one previous mifepristone-induced abortion, and 4,800 women with one previous surgical abortion and followed them through pregnancy and childbirth. The adjusted odds ratio for preterm delivery in women with one mifepristone abortion compared with women with no abortion was 0.77 (95% confidence interval: 0.61, 0.98). Although the mean birth weight of infants born to women with mifepristone abortion was 33 g (95% confidence interval: 17, 49) higher than that of infants born to women with no abortion, the frequencies of low birth weight and mean lengths of pregnancy were similar. There were no significant differences in risk of preterm delivery, frequency of low birth weight, or mean infant birth weight in the comparisons of women with previous mifepristone abortion and women with surgical abortion. This study suggests that one early abortion induced by mifepristone in nulliparous women has no adverse effects on the outcome of a subsequent pregnancy.

Abortifacient Agents, Steroidal↗
PubMed2004

Isoflavones in soy infant formula: a review of evidence for endocrine and other activity in infants.

Soy infant formulas are widely used, but few studies have evaluated long-term safety or examined specific forms of toxicity, such as to the endocrine or immune systems. This review focuses on newer experimental studies of the effects on estrogen activity, immune function, and thyroid economy of genistein and daidzein, two isoflavones in soy infant formula, and existing human studies of soy formula use. In order to judge the likelihood that an endpoint seen in laboratory studies might occur in soy-fed infants, we examined the doses and the resulting serum or plasma concentrations from the laboratory studies and compared them with doses and concentrations seen in soy-fed infants. We also summarized the estimates of the potency of the isoflavone compounds relative to estradiol. Given the scarcity and inconsistency of existing human data and the substantial laboratory evidence of hormonal and other activity at doses relevant to the soy-fed infant, we conclude that more clinical and epidemiological study is warranted.

Dose-Response Relationship, Drug↗
PubMed2004

Breastfeeding and the risk of postneonatal death in the United States.

OBJECTIVE: Breastfed infants in the United States have lower rates of morbidity, especially from infectious disease, but there are few contemporary studies in the developed world of the effect of breastfeeding on postneonatal mortality. We evaluated the effect of breastfeeding on postneonatal mortality in United States using 1988 National Maternal and Infant Health Survey (NMIHS) data. METHODS: Nationally representative samples of 1204 infants who died between 28 days and 1 year from causes other than congenital anomaly or malignant tumor (cases of postneonatal death) and 7740 children who were still alive at 1 year (controls) were included. We calculated overall and cause-specific odds ratios for ever/never breastfeeding among all children, conducted race and birth weight-specific analyses, and looked for duration-response effects. RESULTS: Overall, children who were ever breastfed had 0.79 (95% confidence interval [CI]: 0.67-0.93) times the risk of never breastfed children for dying in the postneonatal period. Longer breastfeeding was associated with lower risk. Odds ratios by cause of death varied from 0.59 (95% CI: 0.38-0.94) for injuries to 0.84 (95% CI: 0.67-1.05) for sudden infant death syndrome. CONCLUSIONS: Breastfeeding is associated with a reduction in risk for postneonatal death. This large data set allowed robust estimates and control of confounding, but the effects of breast milk and breastfeeding cannot be separated completely from other characteristics of the mother and child. Assuming causality, however, promoting breastfeeding has the potential to save or delay approximately 720 postneonatal deaths in the United States each year.

Breast Feeding↗
PubMed2003

Nonmalarial infant deaths and DDT use for malaria control.

Although dichlorodiphenyl trichloroethane (DDT) is being banned worldwide, countries in sub-Saharan Africa have sought exemptions for malaria control. Few studies show illness in children from the use of DDT, and the possibility of risks to them from DDT use has been minimized. However, plausible if inconclusive studies associate DDT with more preterm births and shorter duration of lactation, which raise the possibility that DDT does indeed have such toxicity. Assuming that these associations are causal, we estimated the increase in infant deaths that might result from DDT spraying. The estimated increases are of the same order of magnitude as the decreases from effective malaria control. Unintended consequences of DDT use need to be part of the discussion of modern vector control policy.

Africa South of the Sahara↗
PubMed2002

Surgical management for sciatic nerve injury.

OBJECTIVE: To summarize surgical treatments and their corresponding curative effects on sciatic nerve injuries. METHODS: Surgical treatments on sciatic nerve injury were performed in 28 patients from January 1990 to July 2000. The treatments included neurolysis, neurolysis plus partial nerve anastomosis, nerve anastomosis and nerve transplantation. The curative effect was evaluated according to Sunderland criteria. RESULTS: Of 28 cases, 22 patients were followed up with a follow-up period of 13 months to 5 years (average 30 months). Of 22 nerves, 7 were excellent, 5 good, 7 fair and 3 poor, with an excellence rate of 54.5%. CONCLUSIONS: The fair results of sciatic nerve injury are related to its structural character. Surgical exploration should be performed if nerve function does not recover 3 months after primary operation and if Tinel's sign and electromyogram show no signs of nerve regeneration. Electrophysiological monitoring in the operation is useful in electing surgical methods and predicting the results of nerve anastomosis.

Adolescent↗
PubMed2002

[Bladder controller in bladder function reconstruction of paraplegic dogs].

OBJECTIVE: To observe whether bladder controller can restore bladder function in paraplegic dogs. METHODS: Four dogs were studied after their T(10) spinal cord was transected. Electrodes implanted around S(2) bilaterally were connected to subcutaneous recievers. Microsurgical techniques were employed in dorsal rhizotomy at S(1 - 3) intradural segment. After daily stimulation, the results of bladder controller were evaluated by micturition and vesicography. RESULTS: Micturition was given under electrical stimulation with a urine volume of 80 - 140 ml per time. The mode of micturition was post-stimulus voiding. Vesicography showed that the bladder was filled and bladder neck was open in the micturition course of electric stimulation. Residual urine volume was 15 - 20 ml. CONCLUSION: Bladder controller together with a sacral deafferentation procedure can restore bladder function of paraplegic dogs.

Animals↗
PubMedDate not supplied

Health risks and benefits of bis(4-chlorophenyl)-1,1,1-trichloroethane (DDT).

DDT (bis[4-chlorophenyl]-1,1,1-trichloroethane) is a persistent insecticide that was used worldwide from the mid 1940s until its ban in the USA and other countries in the 1970s. When a global ban on DDT was proposed in 2001, several countries in sub-Saharan Africa claimed that DDT was still needed as a cheap and effective means for vector control. Although DDT is generally not toxic to human beings and was banned mainly for ecological reasons, subsequent research has shown that exposure to DDT at amounts that would be needed in malaria control might cause preterm birth and early weaning, abrogating the benefit of reducing infant mortality from malaria. Historically, DDT has had mixed success in Africa; only the countries that are able to find and devote substantial resources towards malaria control have made major advances. DDT might be useful in controlling malaria, but the evidence of its adverse effects on human health needs appropriate research on whether it achieves a favourable balance of risk versus benefit.

Africa South of the Sahara↗