Chronic environmental inorganic arsenic exposure causes social behavioral changes in juvenile zebrafish (Danio rerio).

Arsenic (As) is a metalloid commonly found worldwide. Environmental As exposure may cause potential health hazards and behavioral changes in humans and animals. However, the effects of environmental As concentrations on social behavior, especially during the juvenile stage, are unclear. In this study, we observed behavioral changes in juvenile zebrafish after 28 days of exposure to inorganic As (NaAsO2 100 and 500 ppb) in water, especially anxiety and social deficits. Additionally, the level of oxidative stress in the zebrafish brain after As treatment increased, the content of dopamine (DA) decreased, and the transcription level of genes involved in DA metabolism with the activity of monoamine oxidase (MAO) increased. Oxidative stress is a recognized mechanism of nerve damage induced by As exposure. The zebrafish were exposed to N-acetylcysteine (NAC) to reduce As exposure-induced oxidative stress. The results showed improvements in social behavior, DA content, MAO activity, and gene transcription in zebrafish. In conclusion, environmental As exposure can induce behavioral abnormalities, such as anxiety and social deficits in zebrafish, which may be caused by As-induced oxidative stress altering gene transcription levels, causing an increase in MAO activity and a decrease in DA.

Prenatal environmental antibiotics and fetal and postnatal growth: A biomonitoring-based prospective study in Eastern China.

Thus far, the effect of environmental antibiotics exposure to offspring's growth remains unclear. Here we aimed to evaluate whether and to what extent environmental antibiotics exposure is associated with fetal and postnatal growth. A total of 735 pregnant women and their full-term offspring from the Shanghai Obesity Birth Cohort were involved in the study. Maternal urine specimen was collected during the third trimester, and urinary concentration of fifteen environmental antibiotics was measured by liquid chromatography-tandem mass spectrometry and enzymatic method. Children were followed at birth, 12, 24 and 60 months, and growth parameters of the weight and height of children were recorded. Linear regression model was applied, and it was found that maternal veterinary antibiotic (VA) concentration was negatively associated with birth weight and ponderal index [per natural-logarithm (ln)-unit: adjusted ß (95% confidence interval, CI) = - 42.1 (- 74.0, - 10.3) for birth weight, -0.11 (- 0.19, - 0.02) for birth weight z-score, and - 0.03 (- 0.05, - 0.002) for ponderal index]. Regarding specific VA, each ln-unit increment of florfenicol concentrations was likely to be associate with 39.7 g (95%CI: - 69.3, - 10.1) reduced birth weight, 0.10 (95%CI: - 0.18, - 0.02) reduced birth weight z-score, and 0.02 g/cm3 (95%CI: - 0.04, - 0.00) reduced ponderal index. Ciprofloxacin, a preferred-as-veterinary antibiotic, showed a similar dose-response relationship with neonatal anthropometric parameters to florfenicol. However, these adverse effects diminished as children grew up to 12-, 24- and 60-month-old. Larger prospective cohort studies and animal experiments are warranted to verify the hypothesis that environmental antibiotics exposure in early life, even at low doses, may cause fetal growth restriction.

Magnetic hydrogel with long in situ retention time for self-regulating temperature hyperthermia.

Aim: Magnetic hydrogels (MHGs) have been proposed to avoid the redistribution and loss of magnetic nanoparticles (MNPs) when administrated by intratumoral injection. However, the requirement of complex cooling systems and temperature monitoring systems still hinder the clinical application of MHGs. This study investigates the feasibility of developing an MHG to realize the self-regulation of hyperthermia temperature. Methods: The MHG was developed by dispersing the MNPs with self-regulating temperature property into the temperature-sensitive hydrogel through physical crosslinking. The MHG's gelation temperature was tested by measuring the storage modulus and loss modulus on a rotational rheometer. The biocompatibility of the MHG and MNPs was characterized by CCK-8 assay against HaCaT cells. The in vivo magnetic heating property was examined through monitoring the temperature in the MHG on mice back upon the application of the alternating magnetic field (400 ± 5 Oe, 100 ± 5 kHz) every week for successive six weeks. Results: The gelation temperature of the MHG falls in 28.4°C-37.4°C. At in vivo applied concentration of 80 mg/mL, the MHG exhibits over 80% cell viability after 72 h, significantly higher than 50% cell viability of the MNPs (p<0.001). The MHG's stable magnetic hyperthermia temperatures in vivo are in the range of 43.4°C-43.8°C. Conclusions: The developed MHG can be injected using a syringe and will solidify upon body temperature. The biocompatibility is improved after the MNPs being made into MHG. The MHG can self-regulate the temperature for six weeks, exhibiting application potential for self-regulating temperature hyperthermia.

Efficacy of Intensive Acupuncture Versus Sham Acupuncture in Knee Osteoarthritis: A Randomized Controlled Trial.

OBJECTIVE: To assess the efficacy of intensive acupuncture (3 times weekly for 8 weeks) versus sham acupuncture for knee osteoarthritis (OA). METHODS: In this multicenter, randomized, sham-controlled trial, patients with knee OA were randomly assigned to receive electroacupuncture (EA), manual acupuncture (MA), or sham acupuncture (SA) 3 times weekly for 8 weeks. Participants, outcome assessors, and statisticians were blinded with regard to treatment group assignment. The primary outcome measure was response rate, which is the proportion of participants who simultaneously achieved minimal clinically important improvement in pain and function by week 8. The primary analysis was conducted using a Z test for proportions in the modified intent-to-treat population, which included all randomized participants who had ≥1 post-baseline measurement. RESULTS: Of the 480 participants recruited in the trial, 442 were evaluated for efficacy. The response rates at week 8 were 60.3% (91 of 151), 58.6% (85 of 145), and 47.3% (69 of 146) in the EA, MA, and SA groups, respectively. The between-group differences were 13.0% (97.5% confidence interval [97.5% CI] 0.2%, 25.9%; P = 0.0234) for EA versus SA and 11.3% (97.5% CI -1.6%, 24.4%; P = 0.0507) for MA versus SA. The response rates in the EA and MA groups were both significantly higher than those in the SA group at weeks 16 and 26. CONCLUSION: Among patients with knee OA, intensive EA resulted in less pain and better function at week 8, compared with SA, and these effects persisted though week 26. Intensive MA had no benefit for knee OA at week 8, although it showed benefits during follow-up.

Fetuin-A in Infants Born Small- or Large-for-Gestational-Age.

Fetuin-A is a multifunctional glycoprotein that has been implicated in insulin resistance and bone metabolism. We assessed whether fetuin-A is associated with poor or excessive fetal growth. In the Shanghai Birth Cohort, we conducted a nested case-control study of 60 trios of small-for-gestational-age (SGA, birth weight <10th percentile), optimal-for-gestational-age (OGA, 25-75th, the reference) and large-for-gestational-age (LGA, >90th percentile) infants matched by sex and gestational age. Cord plasma concentrations of fetuin-A and fetal growth factors [insulin, proinsulin, insulin-like growth factor (IGF)-I and IGF-II] were measured. Cord plasma fetuin-A concentrations were higher in SGA (809.4 ± 306.9 µg/ml, P = 0.026) and LGA (924.2 ± 375.9 µg/ml, P < 0.001) relative to OGA (680.7 ± 262.1 µg/ml) newborns, and were not correlated to insulin, proinsulin, IGF-I and IGF-II (all P > 0.2). Higher fetuin-A concentrations were associated with increased risks of SGA [OR = 1.67 (1.08-2.58) per SD increment, P = 0.024] and LGA [OR = 2.36 (1.53-3.66), P < 0.001]. Adjusting for maternal and neonatal characteristics and fetal growth factors, the elevated risk changed little for LGA [adjusted OR = 2.28 (1.29-4.01), P = 0.005], but became non-significant for SGA (P = 0.202). Our study is the first to demonstrate that fetuin-A may be involved in excessive fetal growth. This association is independent of fetal growth factors.

Correction to: Efficacy of electro-acupuncture and manual acupuncture versus sham acupuncture for knee osteoarthritis: study protocol for a randomised controlled trial.

After publication of the original article [1], the authors have notified us that the Trial registration number NCT03274713 should be replaced by NCT03366363 in the Abstract section of the paper.

Efficacy of electro-acupuncture and manual acupuncture versus sham acupuncture for knee osteoarthritis: study protocol for a randomised controlled trial.

BACKGROUND: Knee osteoarthritis (KOA) is one of the most common musculoskeletal disorders. Although the available evidence for its efficacy is inconclusive, acupuncture is used as an alternative therapy for KOA. The aim of this trial is to determine the efficacy of electro-acupuncture and manual acupuncture versus sham acupuncture for KOA. METHODS/DESIGN: This is a study protocol for a randomised, three-arm, multicentre, clinical trial. A total of 480 patients with KOA will be randomly assigned to the electro-acupuncture group, the manual acupuncture group or the sham acupuncture group in a 1:1:1 ratio. All patients will receive 24 sessions over 8 weeks. Participants will complete the trial by visiting the research centre at week 26 for a follow-up assessment. The primary outcome is the success rate: the proportion of patients achieving a minimal clinically important improvement, which is defined as ≥2 points on the numerical rating scale and ≥6 points on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) function score at week 8 compared with baseline. Secondary outcomes include the numerical rating scale, WOMAC score, global patient assessment and quality of life at weeks 4, 8, 16 and 26 after randomisation. DISCUSSION: This trial may provide high-quality evidence for the efficacy of acupuncture in the treatment of KOA. The results of this study will be published in peer-reviewed journals. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03274713 . Registered on 20 November 2017.

[Effect of penetrating needling at head acupoints on perennial allergic rhinitis].

OBJECTIVE: To evaluate the effects and safety of penetrating needling on head acupoints for perennial allergic rhinitis (PAR). METHODS: Eighty-one cases of PAR were randomly divided into an acupuncture group (41 cases) and a medication group (40 cases). Penetrating needling at head acupoints was adopted from Baihui (GV 20) to Qianding (GV 21) and from Shangxing (GV 23) to Shenting (GV 24) in the acupuncture group. A to tal 4-week treatment was given to the patients with 3 treatments a week. Loratadine tablet and azelastine hydrochloride nasal spray were given to the medication group continuously for 12 days. A follow-up was carried out 3 months after the treatment. The efficacy, symptom score and physical sign score, and side accidents were observed in both groups. RESULTS: The total effective rate was 95.1% (39/41) in the acupuncture group, which was better than 82.5% (33/40) in the medication group (P < 0.05). The total scores of clinical symptoms and each partial scores after the treatment, and total scores of clinical symptoms in follow-up were obviously decreased in both groups (all P < 0.01), the nasal obstruction score and the total scores of clinical symptoms in the acupuncture group were better than those in the medication group (P < 0.01, P < 0.05). Obvious side-effect had not been found during the treatment. CONCLUSION: Penetrating needling at head acupoints is a safe therapy for patients with PAR, and favorable effects can be found in both short term and long term.

[Research on demodulation system for human body temperature measurement of intelligent clothing based on arrayed waveguide grating].

A system for demodulating distributed fiber Bragg grating sensors of the intelligent clothing was researched and realized, which is based on arrayed waveguide grating. The principle of demodulation method based on arrayed waveguide grating was analyzed, intensity--demodulating method was used to interrogate the wavelength of the fiber Bragg grating based on the building up of an experimental platform, and demodulation experiment of pre and post series of fiber Bragg grating was completed. The results show that the wavelength demodulation of the system has high linearity for fiber Bragg grating, the system gives a wavelength accuracy of 0.001 nm, and demodulation error caused by crosstalk between different sensors is 0.0005 nm. The measurement error of human body temperature is +/- 0.16 degrees C. It can be applied to the human body temperature measurement.

Fecal calprotectin levels are higher in rural than in urban Chinese infants and negatively associated with growth.

BACKGROUND: Fecal calprotectin (FC) is an established simple biomarker of gut inflammation. To examine a possible relationship between linear growth and gut inflammation, we compared fecal calprotectin levels in 6 month old infants from poor rural vs affluent urban families. METHODS: The project was a cross-sectional comparison of FC from rural and urban populations in China. The relationship between length-for-age Z-score (LAZ) and FC concentrations were also compared. Single fecal samples were assayed for FC using EK-CAL ELISA kits. RESULTS: The age of subjects for both locations was 6.1 ± 0.2 mo; all were apparently healthy. The mean ± SD of the LAZ for the rural and urban infants were -0.6 ± 0.9 and 0.4 ± 0.9, respectively. FC had a non-normal distribution. The median FC of 420.9 and 140.1 µg/g for rural and urban infants, respectively, were significantly different (P < 0.0001). For the rural group, linear regression analysis showed that an increase in FC of 100 µg/g was associated with a decrease of 0.06 in LAZ. CONCLUSION: FC levels were significantly elevated in the rural infants and high concentrations accounted for approximately one-third of the low LAZ scores of these infants.

[Observation on therapeutic effect of acupuncture combined with medicine on mild cognition disorders in patients with post-stroke].

OBJECTIVE: To explore the curative effect and safety of acupuncture for mild cognitive disorders after stroke. METHODS: Randomized controlled trial was adopted and one hundred cases conforming to criteria were divided into a combined acupuncture and medication group (group A) and a medication group (group B), 50 cases in each group. The basic treatment of cerebrovascular disease was applied in two groups. The group A treated was with acupuncture at Baihui (GV 20), Shenting (GV 24) and Qucha (BL 4) etc. and oral administration of Nimodipine. In group B, Nimodipine was taken orally. The treatment lasted for 3 months, the scores of Mini-Mental State Examination (MMSE), modified Hasegawa Dementia Scale (HDS-R) and Barthel Index (BI) were observed before and after treatment in two groups. RESULTS: The total effective rate in group A was 66.7% (32/48), which was superior to 30.4% (14/46) in group B (P < 0.05). The scores of MMSE, HDS-R and BI after treatment were apparently improved as compared with those before treatment in two groups (all P < 0.01). The improvements in group A were superior to those in group B (all P < 0.05). There was no adverse event reported during the treatment in two groups. CONCLUSION: Acupuncture can improve activity of daily living and has significant effect in treating mild cognition disorders after stroke without adverse reactions.

[Exposure level and risk factors of heavy metal in prenatal period among Shanghai infants].

OBJECTIVE: To explore the exposure level and risk factors of heavy metal among Shanghai infants in their prenatal period. METHODS: A total of 1652 pregnant or puerperal women were recruited from 10 midwifery-qualified hospitals in Shanghai since October 2008 to October 2009, by the stratified cluster sampling method. They answered the questionnaire and their umbilical cord blood and serum were collected to detect the content of Pb, Hg, Mn, Cd, As and Tl. The risk factors were analyzed by single and multiple regression methods respectively. RESULTS: The median value of the content of Pb, Hg, Mn, Cd, As and Tl were 41.00, 1.88, 4.10, 0.03, 0.86 and 0.02 µg/L respectively. The Hg concentration of pregnant women who ate fish for 4 - 7 times per week (9.7% (160/1652)) was 2.76 µg/L, which was higher than that of pregnant women who only ate fish for 1-3 times per week (49.3% (814/1652)) and those who seldom ate fish (40.0% (661/1652)); the Hg concentration in the two groups above were 2.41 and 2.03 µg/L separately. The difference had statistical significance (χ(2) = 36.40, P < 0.001). Meanwhile, the concentrations of Pb and Tl in the group of pregnant women whose houses were remodeled by PVC pipe (85.0% (1404/1652)) was higher than the concentrations in group of pregnant women whose houses were remodeled by galvanized pipe (15.0% (248/1652)); the Pb concentration in the two groups above were 45.54 and 40.00 µg/L (Z = 2.54, P < 0.05) and the Tl concentration in the two groups above were 0.021 and 0.018 µg/L (Z = 2.97, P < 0.05). However, the As concentration in the group of PVC pipe remodeled was 4.33 µg/L, which was lower than that in the group of galvanized pipe (9.37 µg/L). The difference had statistical significance (Z = 3.99, P < 0.01). The concentrations of Mn, Cd and Tl in the groups of pregnant women whose house had been remodeled in the last 3 years (38.0% (628/1652)) were 14.78, 0.51 and 0.022 µg/L separately, which were all significantly higher than those in the groups of women whose houses' were not remodeled (62.0% (1024/1652)), whose concentrations were 11.01, 0.29 and 0.02 µg/L respectively. The differences had statistical significance (Mn: Z = 2.46, P < 0.05; Cd: Z = 2.38, P < 0.05; Tl: Z = 2.81, P < 0.01). CONCLUSION: The infants in Shanghai were exposed to heavy metals in their prenatal period. The main sources of the exposure were daily diet and remodeled pollution.

Prenatal exposure to multiple toxic heavy metals and neonatal neurobehavioral development in Shanghai, China.

BACKGROUND: Epidemiological studies examining the effects of prenatal toxic heavy metals exposure on neonatal development at the population-based level are limited. OBJECTIVE: To explore prenatal exposure levels to toxic heavy metals and examine whether exposure is associated with neonatal development. METHODS: A stratified multi-stage cluster sampling methodology was used to investigate 1652 mother-infant pairs from 2008 through 2009 in Shanghai. Cord blood concentrations of Pb, Hg, Cd, As, Tl and NBNA (Neonatal Behavioral Neurological Assessments) were tested. We defined three different exposure levels (low, medium and high) according to the considered safe values. RESULTS: The median blood Pb, Hg, Cd, As and Tl concentrations were 41 µg/L, 1.88 µg/L, 0.03 µg/L, 0.86 µg/L and 0.02 µg/L, respectively, which all were in the level considered safe. Increasing exposure to Cd, Hg, As and Tl during pregnancy was associated with decreasing NBNA scores. High level-exposure (exceeding the level considered safe) of Hg, Cd and Tl had lower NBNA scores compared to medium and low levels (both in the level considered safe), which implied that the level considered safe of these heavy metals was safe for the newborns' development. The mean decreasing scores of NBNA was 0.61, 1.50 and 0.84 (total score = 40) with high-level exposure of Hg, Cd and Tl, respectively. The medium-level exposure (in the level considered safe) to As had lower NBNA scores compared to low-level exposure, which implied that level of considered safe for As was not safe to the newborns' development. However, prenatal Pb high-exposure did not affect NBNA scores either by single or multiple factor analysis. In addition, important contribution factors for heavy metals pollutants were diet, lifestyle and housing renovation. CONCLUSIONS: Prenatal heavy metals except Pb exposures were associated with NBNA. The adverse effect of medium-level As warrants the need to further investigate the safe range of As.

[Clinical observation on therapeutic effect of three-step acupuncture for the secondary prevention of ischemic cerebral apoplexy].

OBJECTIVE: To observe the therapeutic effect and safety of three-step acupuncture for the secondary prevention of ischemic cerebral apoplexy. METHODS: One hundred and twenty cases of first-episode ischemic cerebral apoplexy were randomly divided into an observation group and a control group according to the visiting sequence, 60 cases in each group. Both groups were treated on the basis of the routine treatment, the observation group was treated with three-step acupuncture combined with oral administration of Aspirin for six months. The threestep acupuncture includs scalp acupuncture, body point acupuncture and rehabilitation training. The control group was treated with oral administration of Aspirin alone. Six-month follow-up was done in two groups. Then the recurrence rate of ischemic cerebral apoplexy, the improvement of neurologic impairment, activity of daily living and TCM symptom scores and the safety of three-step acupuncture between two groups were compared. RESULTS: The recurrence rate was 10.2% (5/49) in observation group, and 16.7% (9/54) in control group. There was no significant difference between two groups (P > 0.05). The observation group was superior to the control group in improving the scores of the neurologic impairment, activity of daily living and TCM symptom (P < 0.01, P < 0.001). There was no severe adverse reaction in two groups except 2 cases of gastrointestinal reaction caused by oral administration of Aspirin in control group. CONCLUSION: Three-step acupuncture has a certain therapeutic effect for both treatment and the secondary prevention of ischemic cerebral apoplexy, and it is one of the safe and effective methods for treating and preventing ischemic cerebral apoplexy in clinic.

[Effects of chelation therapy with succimer in young rabbits of moderate lead poisoning].

OBJECTIVE: To explore the effect of chelation therapy with succimer (DMSA) in male rabbits of moderate lead poisoning during juvenile stage. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

[Effects of chronic partial sleep deprivation on growth and learning/memory in young rats].

OBJECTIVE: The effects of sleep deprivation on the immature brain remain unknown. Based on a computer controlled chronic sleep deprivation animal model, the effects of chronic partial sleep deprivation on growth, learning and memory in young rats were explored. METHODS: Twelve weaned male Spraque-Dawley rats (3-week-old) were randomly divided into sleep deprivation, test control and blank control groups. Sleep deprivation was performed using computer-controlled "disc-over-water" technique at 8-11 am daily, for 14 days. The temperature and weights were measured every 7 days. Morris water maze was used to test spatial learning and memory abilities before and 7 and 14 days after sleep deprivation. After 14 days of sleep deprivation, the rats were sacrificed for weighting their major organs. RESULTS: After 14 days of sleep deprivation, the rats' temperature increased significantly. During the sleep deprivation, the rate of weight gain in the sleep deprivation group was much slower than that in the test control and blank control groups. The thymus of the rats subjected to sleep deprivation was much lighter than that of the blank control group. After 7 days of sleep deprivation, the rats showed slower acquisition of reference memory, but were capable of successfully performing the task by repeated exposure to the test. Such impairment of reference memory was not seen 14 days after sleep deprivation. CONCLUSIONS: Chronic sleep deprivation can affect growth of immature rats, as well as their abilities to acquire spatial reference memory.

[Effects of moderate lead poisoning on the hippocampus tissue of rabbits in juvenile stage].

OBJECTIVE: To understand the effects of moderate lead poisoning on the hippocampus tissue of rabbits in juvenile stage. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

[Effects of lead exposure on expression of mGluR5 in mRNA and protein levels of the cultured hippocampal neurons].

OBJECTIVE: To study the effects on the expression of mGluR5 mRNA and protein levels in primarily cultured hippocampal neurons after lead exposure. METHODS: Primary embryonic rat hippocampal neuronal culture was prepared. On the 3(rd) day of incubation, lead chloride solution was added into medium to produce four different lead exposure levels: 0, 1 x 10(-8) mol/L, 1 x 10(-6) mol/L, 1 x 10(-4) mol/L Pb(2+). After 10 days of incubation, the neurons were collected to measure the alteration of mGluR5 mRNA expression by real-time fluorescent quantity PCR and the expression of mGluR5 in protein level by Western blot. RESULTS: The studies revealed that mGluR5 mRNA expression was down-regulated after lead exposure in a dose-dependent manner. The mGluR5 mRNA expression of the lower lead-exposed neurons (Pb(2+) 10(-8) mol/L), the medium lead-exposed neurons(Pb(2+) 10(-6) mol/L), the higher lead-exposed neurons(Pb(2+) 10(-4) mol/L) were 0.724, 0.421, 0.321 times less than that of the controls, respectively. The Western blot demonstrated that mGluR5 expression in protein level should be decreased after lead exposure. CONCLUSION: The expression of mGluR5 in mRNA and protein levels should be down-regulated after lead exposure at different lead levels in a dose-dependent manner.

[Preweaning exposure to enriched environment induces hippocampal neurogenesis: experiment with rats].

OBJECTIVE: To explore the effects of preweaning exposure to enriched environment on hippocampal neurogenesis and the underlying mechanisms. METHODS: Thirty-six 10-day-old SD rats were randomly divided into the 2 equal groups: control group and enriched environment group (EE group. From the age of 10 days to 24 days the rats received intraperitoneal injection of bromodeoxyuridine (BrdU) 50 mg/kg every other day to label the newly proliferated cells in vivo, and the rats in EE group were daily exposed to enriched environment for 20 minutes. Six rats of each group were sacrificed whren they were 24 days of age. Nuclear protein of the hippocampus was extracted to undergo Western blotting to detect the levels of calmodulin and phosphorylated CREB (cAMP response element binding). Other rats were sacrificed at the age of 63 days. Coronal cryostat sections of brain were cut. Sections at the level 3.6 mm posterior to the bregma were obtained and stained with methyl aniline blue and the number of cells in the hippocampal dentate gurus (DG) of the right hemisphere were counted using x 400 microscope. BrdU immunohistochemistry and double immunofluorescence labeling with BrdU/NeuN or BrdU/GFAP were done, and the numbers of BrdU-labeled cells and ratios of neurons and astrocytes differentiated from BrdU-labeled cells were calculated. RESULTS: The levels of calmodulin and phosphorylated CREB in the hippocampal nuclear extract of the EE group were 0.065 +/- 0.035 and 0.485 +/- 0.007 respectively, both significantly higher than those of the control group (0.245 +/- 0.035 and 0.220 +/- 0.014 respectively, P = 0.01 and P = 0.002). The number of cells in the DG area of right hippocampus 3.6 mm posterior to bregma of the EE group was 1580 +/- 72, significantly higher than that of the control rats (1375 +/- 62, t = -7.461, P < 0.01). The number of BrdU labeled cells of the EE group was 5363 +/- 487, significantly higher than that of the control group (2984 +/- 318, t = -14.177, P < 0.01). The ratio of neurons of the EE group was 85.0% +/- 2.8%, significantly higher than that of the control group (80.2% +/- 2.8%, t = -4.166, P < 0.01). The differentiation rate of astrocytes of the EE group was 4.0% +/- 0.5%, significantly higher than that of the control group (2.6% +/- 0.6%, t = -6.493, P < 0.01). CONCLUSION: Preweaning exposure to enriched environment can induce neurogenesis. The underlying mechanism may be that enriched environment induces the activation of calmodulin and CREB in hippocampus.

Prenatal exposure to mercury and neurobehavioral development of neonates in Zhoushan City, China.

Exposure to hazardous Hg can adversely affect children's neurodevelopment. However, few data are available on either Hg levels in neonates and their mothers or the impact of prenatal exposure to Hg on neonates' neurobehavioral development in the Chinese population. Therefore, this study examined Hg levels in neonates and their mothers and the relationship between prenatal exposure to Hg and neonates' neurobehavioral development in Zhoushan City, Zhejiang Province, China. Between August and October 2004, 417 women who delivered their babies at Zhoushan Women's and Children's Health Hospital, an island city in east China were invited to take part in this study. A total of 408 complete questionnaires, 405 maternal hair samples, and 406 umbilical cord samples were collected. Neonatal behavioral neurological assessments (NBNA) were conducted for 384 neonates. The geometric mean (GM) of Hg level in cord blood was 5.58 microg/L (interquartile range: 3.96-7.82 microg/L), and the GM of maternal hair Hg level was 1246.56 microg/kg (interquartile range: 927.34-1684.67 microg/kg), a level much lower than other reported fish-eating populations, indicating Hg exposure in Zhoushan city is generally below those considered hazardous. However, according to the reference dose of Hg levels (RfD 5.8 microg/L) derived by EPA, 69.9% of newborns had levels at or above the RfD, an estimated level assumed to be without appreciable harm. There was a strong correlation between maternal hair and cord blood Hg levels (r = 0.82, P < 0.01). Frequency of fish consumption was associated with hair Hg (r = 0.48, P < 0.01) and cord blood Hg levels (r = 0.54, P < 0.01). Increased prenatal Hg exposure was associated with decreased behavioral ability for males (OR = 1.235, 95%CI of OR = 1.078-1.414, P < 0.001), but not for females. Our results provide some support for the hypothesis that there is neurodevelopmental risk for males from prenatal MeHg exposure resulting from fish consumption. But the findings of this study may be due to chance, and long-term follow-up research is needed to evaluate cumulative effects of exposure to mercury.