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Background We aimed to analyze the characteristics of the body composition of children and adolescents aged 3–17 in Suzhou, China. Methods A cross-sectional study between January 2020 and June 2022 using bioelectrical impedance was conducted to determine the fat mass (FM), fat-free mass (FFM), skeletal muscle mass, and protein and mineral contents of 24,845 children aged 3–17 who attended the Department of Child and Adolescent Healthcare, Children’s Hospital of Soochow University, China. Normally distributed data were expressed as mean ± SD, and groups were compared using the independent samples t-test. Results FM and fat-free mass increased with age in both boys and girls. The fat-free mass of girls aged 14–15 decreased after reaching a peak, and that of boys in the same age group was higher than that of the girls (p p p

Human melanoma is a highly aggressive type of cancer, causing significant mortalities despite the advances in treatment. Carboplatin is a cisplatin analog necessary for the treatment of various cancers and can also be used to treat human melanoma. We assessed the effects and mechanisms leading to inhibited proliferation and induced apoptosis of human melanoma after carboplatin therapy in vitro and in vivo. TREX1, cGAS/STING, and apoptotic protein expressions were determined through RT-qPCR and western blot assays. Cell proliferation was validated through MTT assays. The study used SK-MEL-1 and SK-HEP-1 tumor cell line inoculations along with carboplatin in nude mice to validate the results. The TREX1 levels were down-regulated in human melanoma cell lines. TREX1 overexpression-induced apoptosis and decreased proliferation in the human melanoma cell lines. TREX1 overexpression also activated the cGAS/STING pathway to induce apoptosis and decrease cell growth. Carboplatin activated TREX1, induced apoptosis, and decreased proliferation in the human melanoma cancerous cell lines. Finally, carboplatin reduced the in-vivo tumor size and weight. In conclusion, the study revealed that carboplatin activated TREX1 and cGAS/STING pathways to upregulate apoptosis. The work also provides in vitro and in vivo evidence to understand the effects of TREX overexpression on tumor suppression. Targeting of TREX1/cGAS/STING pathway could be an effective therapeutic alternative to human melanoma.

Transforming acidic coiled coil containing protein 3 (TACC3) is emerging as an attractive anticancer target in recent years, however, few TACC3 small-molecular inhibitors have been reported up to now. In this study, fifteen compounds were designed and synthesized based on the lead compound KHS101 to find more potent TACC3 inhibitors. Among them, the most potent compound 7g exhibited about 10-folds more potent antiproliferative activities than KHS101 in various cancer cell lines. Two different protein-drug binding assays including DARTS, and CETSA revealed TACC3 as a biologically relevant target of compound 7g. In addition, compound 7g induced cell cycle arrest at the G2/M phase and induced cell apoptosis. Furthermore, compound 7g depolarized the MMP and induced ROS generation in a dose-dependent manner in U87 cells. More importantly, 7g reduced tumor weight by 72.7% in U87 xenograft model at a dose of 20 mg/kg/day without obvious toxicity. Altogether, compound 7g deserved further investigations as a novel, safe and efficacious TACC3 inhibitor for the treatment of GBM.

Background Our study aimed to explore the anxiety levels and possible associated factors in the pediatric medical staff in Jiangsu province during an outbreak of Coronavirus Disease 2019 (COVID-19). Methods Pediatric medical staff (n=534) from nine hospitals in Jiangsu province were enrolled. Their anxiety levels and quality of sleep were assessed using the online SAS and PSQI questionnaires. Results The prevalence of anxiety was 14.0% among the medical staff. In children's hospital staff, anxiety levels in outpatient and emergency departments were significantly higher than those in inpatient departments, except for the intensive care unit. The SAS scores were significantly associated with educational background, professional title, lifestyle, and physical condition. Stepwise multiple linear regression showed that physical condition, lifestyle, attention to the epidemic, professional title, and educational background all had a linear relationship with the individual's anxiety levels. Pearson correlation analysis showed that sleep quality was moderately associated with anxiety levels. Conclusions The prevalence of anxiety was 14.0% in pediatric medical staff in Jiangsu province during an outbreak of COVID-19. Department, professional title, and educational background were associated with anxiety levels in these workers. More attention should be paid to staff who are in poor health, and this anxiety can also be accompanied by poor sleep quality. Peer support can assist with anxiety relief.

ObjectivesThe aim of this study was to assess comorbidity patterns and functional impairment in children with and without attention deficit hyperactivity disorder (ADHD).DesignHospital-based retrospective cross-sectional study; data collection occurred between 2016 and 2019.Settings and patientsA total of 8256 children and adolescents, 6–17 years of age, with suspected ADHD agreed to participate in this hospital-based cross-sectional study over a 4-year period in China. Comorbidities and social functions were assessed according to the scales Vanderbilt ADHD Diagnostic Parent Rating Scale and Weiss Functional Impairment Rating Scale-Parent Form, which were completed by the parents of the study participants.ResultsOf the 8256 children, 5640 were diagnosed with ADHD. Other 2616 children who did not meet the ADHD diagnostic criteria were classified as the N-ADHD group . The proportion of comorbidities (47.4%) and functional impairments (84.5%) in the ADHD group were higher than the N-ADHD group (p≤0.001). The functional impairment scores in all of the six domains, including family, academic, life skills, self-concept, social activities and risky activities, were significantly higher in the ADHD group than the N-ADHD group (p≤0.001). The functional impairment in ADHD group with comorbidities was more severe than those without comorbidities (p≤0.001). Comorbidities and core symptoms both can affect the functions of children with ADHD. Logistics regression analysis indicated that in all of the six functional domains, the effect of comorbidities on functional impairment exceeded the effects of ADHD core symptoms.ConclusionsComorbidities had the greatest influence on different areas of adaptive functioning in children with ADHD. Clinical management of children suspected to have ADHD should address multiple comorbidities and functional impairments assessment, as well as core symptom analysis.

Glioblastoma is one of the most aggressive primary brain tumors with few treatment strategies. β-Elemene is a sesquiterpene known to have broad spectrum antitumor activity against various cancers. However, the signaling pathways involved in β-elemene induced apoptosis of glioblastoma cells remains poorly understood. In this study, we reported that β-elemene exhibited antiproliferative activity on U87 and SHG-44 cells, and induced cell death through induction of apoptosis. Incubation of these cells with β-elemene led to the activation of caspase-3 and generation of reactive oxygen species (ROS). Western blot assay showed that β-elemene suppressed phosphorylation of STAT3, and subsequently down-regulated the activation of p-JAK2 and p-Src. Moreover, pre-incubation of cells with ROS inhibitor N-acetyl-L-cysteine (NAC) significantly reversed β-elemene-mediated apoptosis effect and down-regulation of JAK2/Src-STAT3 signaling pathway. Overall, our findings implied that generation of ROS and suppression of STAT3 signaling pathway is critical for the apoptotic activity of β-elemene in glioblastoma cells.

Background: Premature ovarian failure (POF) refers to pathological amenorrhea before 40 years. Aim/Objective: To explore the regulatory effect of Rg1 on POF and clarify associated mechanisms. Materials and Methods: POF mice were induced by injecting with D-galactose (D-gal, 200 mg/kg/- day). Mice were divided into phosphate buffered saline (PBS), D-gal (POF mice), D-gal/Rg1 group (POF mice administrating D-gal/Rg1). Weight growth rate and ovarian weight coefficient were measured. Serum estradiol (E2), follicle stimulating hormone (FSH), luteinizing hormone (LH), superoxide dismutase (SOD), catalase (CAT) levels were examined using ELISA. The status of follicle and corpus luteum was determined using hematoxylin-eosin (HE) staining. P16INK4a and silent- mating type information regulation-2 homolog-1 (SIRT1) were determined using western blotting and RT-PCR. Results: Weight growth rate and ovarian weight coefficient of mice in D-gal group were significantly decreased than PBS group (p Conclusions: Rg1 could delay premature ovarian failure in D-gal induced POF mouse model through downregulating p16INK4a and upregulating SIRT1 expression.

The hematopoietic system is one of the potential targets of lead intoxication. Recognition of the lead-related deleterious outcomes promotes us to explore the potential therapeutic intervention. Here, we show that ginsenoside Rg1 (Rg1), extracted from the Chinese herb Panax ginseng, remarkably ameliorates the lead acetate-caused hematological index distortion as well as advanced hematopoietic stem cells (HSCs) aging and aging associated inflammation response. Specifically, Rg1 administration alleviated the increment of aging associated p53-p21-Rb signaling in aged HSCs induced by lead acetate. It also led a reduction of the lead acetate-induced increased inflammation level in blood plasma, which also partly contribute the aged HSCs rejuvenation. In conclusion, our results indicate that ginsenoside Rg1 therapeutically alleviated the essential blood deficits and advanced HSCs aging by lead acetate exposure, by which it could be viewed as a potential candidate for lead acetate-caused blood toxicity treatment.

Naturally occurring polyphenol curcumin (4) or demethoxycurcumin (5) and their synthetic derivatives display promising anticancer activities. However, their further development is limited by low bioavailability and poor selectivity. Thus, a mitochondria-targeted compound 14 (DMC-TPP) was prepared in the present study by conjugating a triphenylphosphine moiety to the phenolic hydroxyl group of demethoxycurcumin to enhance its bioavailability and treatment efficacy. The in vitro biological experiments of DMC-TPP showed that it not only displayed higher cytotoxicity as compared with its parent compound 5, but also exhibited superior mitochondria accumulation ability. Glioma cells were more sensitive to DMC-TPP, which inhibited the proliferation of U251 cells with an IC50 of 0.42 μM. The mechanism studies showed that DMC-TPP triggers mitochondria-dependent apoptosis, caused by caspase activation, production of reactive oxygen species (ROS) and decrease of mitochondrial membrane potential (MMP). In addition, DMC-TPP efficiently inhibited cellular thioredoxin reductase, which contributed to its cytotoxicity. Significantly, DMC-TPP delayed tumor progression in a mouse xenograft model of human glioma cancer. Taken together, the potent in vitro and in vivo antitumor activity of DMC-TPP warrant further comprehensive evaluation as a novel anti-glioma agent.

Hematopoietic stem cells (HSCs) aging is associated with hematopoietic dysfunction and diseases. Our previous study showed that lead exposure induced a functional decline in HSCs. Allicin, a chemical extracted from the garlic (Allium sativum L.), has been reported to have antioxidative and anti-inflammatory effects. However, the biological activities of allicin on lead-induced toxicity, especially in the hematopoietic system, remain unclear. Here, we found that lead exposure elicited aging phenotypes in HSCs, including perturbed cell quiescence, disabled self-renewal function and colony-forming ability, and myeloid-biased differentiation, all of which contributed to significant hematopoietic disorders in mice. Intragastric administration of allicin substantially ameliorated lead-induced HSCs aging phenotypes in vivo. Lead exposure induced a peroxide condition in HSCs leading to DNA damage, which reduced expression of the glycolytic enzyme pyruvate kinase M2 isoform (PKM2), a phenotype which was significantly ameliorated by allicin treatment. These findings suggested that allicin alleviated lead-induced HSCs aging by up-regulating PKM2 expression; thus, it could be a natural herb for preventing lead toxicity.

Objective.The effects of lead exposure on cognitive function have been studied intensively over the past decade, but less attention has focused on its impact on auditory function. This study is aimed at investigating the effect of lead on the cochlea and the molecular mechanisms responsible for its actions.Methods.0.2% lead acetate was administered to rats in drinking water for 30, 60, and 90 days. Brainstem auditory evoked responses (ABR) were recorded, and morphological changes in the hair cells were observed. We also measured glutathione (GSH) and malondialdehyde (MDA) concentrations and antioxidant enzyme activities such as catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and glutathione reductase (GR) activities in the cochlea.Results.Lead exposure increased the ABR threshold and slightly prolonged the latencies of wave II and wave IV in rats. Abnormally shaped hair cells and loss of hair cells were found in the cochlea basilar membrane, together with degenerative changes in spiral ganglion neurons following lead exposure. The activities of some antioxidant enzymes were also reduced in association with upregulation of MDA expression. These effects may be caused by impaired catalytic function of the enzymes as a result of lead interaction.Conclusion.The antioxidant system of the cochlea in the immature rat brain is highly vulnerable to developmental lead exposure. Oxidative stress may therefore represent a possible mechanism for lead-induced auditory deficits.

Despite the global abundance of studies on children’s lead (Pb) exposure, the magnitude of Pb exposure among children across China remains unclear, especially for rural areas. In 2000, Pb was removed from petrol, marking a change in the sources of Pb exposure in China. To better understand children’s Pb exposure and inform potential approaches to exposure reduction, we conducted a national blood Pb survey of 31,373 children (0–84 months old) from May 2013 to March 2015, using a multi-stage and multi-strata sampling method. Blood lead levels (BLLs) were tested using graphite furnace atomic absorption spectrometry with a detection limit of 1 µg/L. The results show that Chinese children had a contemporary geometric mean (GM) BLL of 26.7 μg/L, with 8.6% of BLLs exceeding 50 µg/L. Boys had higher BLLs (GM 27.2 μg/L) compared to girls (GM: 25.9 μg/L) (p

In adults, bone hematopoietic cells are responsible for the lifelong production of all blood cells. It is affected in aging, with progressive loss of physiological integrity leading to impaired function by cellular intrinsic and extrinsic factors. However, intervention measures, which directly inhibit the aging of hematopoietic cells, remain to be investigated. In the present study, 10 µmol/l ginsenoside Rg1 (Rg1) markedly alleviated the aging phenotypes of Sca‑1+ hematopoietic cells following in vitro exposure. In addition, the protective effects of ginsenoside Rg1 on the aging of Sca‑1+ hematopoietic cells was confirmed using a serial transplantation assay in C57BL/6 mice. The mechanistic investigations revealed that Rg1‑mediated Sca‑1+ hematopoietic cell aging alleviation was linked to a series of characteristic events, including telomere end attrition compensation, telomerase activity reconstitution and the activation of genes involved in p16‑Rb signaling pathways. Based on the above results, it was concluded that ginsenoside Rg1 is a potent agent, which acts on hematopoietic cells to protect them from aging, which has implications for therapeutic approaches in hemopoietic diseases.

We analyzed the epidemiological data during 1990–2012 that investigated the blood lead level (BLL) in the population aged 0–18 years old in China mainland and provided evidence of the benefits of implementing policies to prevent lead pollution based on the dynamic changes of BLL. Data were collected through databases including China Knowledge Resource Integrated Database (CNKI), CBM disc, Wanfang Data, Pubmed and Medline. The inclusion criteria were: 1. Epidemiological study in healthy population not included studies limited to specific patient; 2. Study subject was not the specific lead exposure population; 3. Sample size should be no less than 100 (for neonatal, no less than 50); 4. BLL detection was under strict quality control; and 5. Results should be presented as BLL (arithmetic mean level or geometric mean level). 62 articles were included in this study. All the surveys in these articles contained 189,352 subjects in 19 provinces, autonomous regions and municipalities. Linear regression analysis showed a significant decrease between 1990 and 2012 with an estimated regression coefficient of 3.05/year (SE = 0.01, p

Aims It is a promising approach to search the therapeutic strategies for treating lead (Pb) toxicity. Allicin, a natural compound extracted from Allium sativum (garlic), has been reported to have many beneficially biological properties. In this study, we investigated the protective effects of allicin on learning and memory function of rats exposed by lead acetate at developmental stage. Materials and methods Rats received lead acetate for inducing toxicity, and gavaged with allicin to ameliorate this toxicity. Morris water maze test was performed to determine learning and memory function. Superoxide dismutase (SOD), glutathione (GSH) and methane dicarboxylic aldehyde (MDA) was measured to determine oxidative stress. Immunofluorescence was carried out to analyze GFAP-positive cells. The protein expression of ERK, p-ERK, EGFR and p-EGFR were detected using western blot. Key findings We found that allicin ameliorated lead acetate-caused learning and memory deficits by promoting hippocampus astrocyte differentiation, which mainly through EGFR/ERK signaling. Moreover, allicin attenuated the increased ROS level by regulating the oxidative defense system. Significance These results suggest that allicin is a potent agent able to ameliorate lead acetate-induced learning and memory deficits during early development, and may thus be useful for defeating lead acetate toxicity.

Leukemia stem cells (LSCs) play important roles in leukemia initiation, progression and relapse, and thus represent a critical target for therapeutic intervention. Hence, it is extremely urgent to explore new therapeutic strategies directly targeting LSCs for acute myelogenous leukemia (AML) therapy. We show here that Angelica sinensis polysaccharide (ASP), a major active component in Dong quai (Chinese Angelica sinensis), effectively inhibited human AML CD34 + CD38 − cell proliferation in vitro culture in a dose-dependent manner while sparing normal hematopoietic stem and progenitor cells at physiologically achievable concentrations. Furthermore, ASP exerted cytotoxic effects on AML K562 cells, especially LSC-enriched CD34 + CD38 − cells. Colony formation assays further showed that ASP significantly suppressed the formation of colonies derived from AML CD34 + CD38 − cells but not those from normal CD34 + CD38 − cells. Examination of the underlying mechanisms revealed that ASP induced CD34 + CD38 − cell senescence, which was strongly associated with a series of characteristic events, including up-regulation of p53, p16, p21, and Rb genes and changes of related cell cycle regulation proteins P16, P21, cyclin E and CDK4, telomere end attrition as well as repression of telomerase activity. On the basis of these findings, we propose that ASP represents a potentially important agent for leukemia stem cell-targeted therapy.

The relationship between prenatal stress (PS) exposure and neurodevelopmental deficits remains inconclusive, especially when assessing the role of PS duration and timing and sex-dependent effects. This study explored a sex-specific association between the duration and timing of exposure and the outcomes of PS-induced neurotoxicity in hippocampal microstructure, synaptophysin expression, and neurobehavioral performance in rats. Pregnant rats were randomly assigned to control, PS-ML (exposed to prenatal restraint stress in the mid-to-late period of pregnancy), or PS-L (exposed in the late period of pregnancy) groups, and offspring in each group were divided into two subgroups by sex. Surface-righting reflex test, cliff avoidance test and Morris water maze test showed that neurodevelopmental levels were reduced in PS-treated pups but without significant sex differences. On postnatal day 22, hippocampal microstructure was examined by electron microscopy, and the expression of hippocampal synaptophysin was assessed by western blot. Abnormal ultrastructural appearance of hippocampal neurons and myelin sheaths, more degenerating neurons and higher G-ratios were found in young PS-ML and PS-L rats as well as reduced expression of hippocampal synaptophysin, although PS-ML pups were more greatly affected than PS-L, with males showing slightly greater impairments than females. These findings suggest that hippocampal hypo-myelination and decreased synaptophysin expression in neurodevelopment may be a duration and time-dependent effect of prenatal stress exposure, modified slightly by sex.

Aims and Background: Traditional chemotherapy strategies for human leukemia commonly use drugs based on cytotoxicity to eradicate cancer cells. One predicament is that substantial damage to normal tissues is likely to occur in the course of standard treatments. Obviously, it is urgent to explore therapies that can effectively eliminate malignant cells without affecting normal cells. Our previous studies indicated that ginsenoside Rg 1 (Rg 1 ), a major active pharmacological ingredient of ginseng, could delay normal hematopoietic stem cell senescence. However, whether Rg 1 can induce cancer cell senescence is still unclear. Methods: In the current study, human leukemia K562 cells were subjected to Rg 1 exposure. The optimal drug concentration and duration with K562 cells was obtained by MTT colorimetric test. Effects of Rg 1 on cell cycle were analyzed using flow cytometry and by SA-β-Gal staining. Colony-forming ability was measured by colony-assay. Telomere lengths were assessed by Southern blotting and expression of senescence-associated proteins P21, P16 and RB by Western blotting. Ultrastructural morphology changes were observed by transmission electron microscopy. Results: K562 cells demonstrated a maximum proliferation inhibition rate with an Rg 1 concentration of 20 μ mol·L -1 for 48h, the cells exhibiting dramatic morphological alterations including an enlarged and flat cellular morphology, larger mitochondria and increased number of lysosomes. Senescence associated-β-galactosidase (SA-β-Gal) activity was increased. K562 cells also had decreased ability for colony formation, and shortened telomere length as well as reduction of proliferating potential and arrestin G 2 /M phase after Rg 1 interaction. The senescence associated proteins P21, P16 and RB were significantly up-regulated. Conclusion: Ginsenoside Rg 1 can induce a state of senescence in human leukemia K562 cells, which is associated with p21-Rb and p16-Rb pathways.

Lead (Pb) is a toxic heavy metal widespreadly used in industrial field. Prior studies showed that Pb exposure had detrimental effects on osteoblasts. The mechanisms underlying Pb-induced damage are complex. Autophagy can protect cells from various cytotoxic stimuli. In the present study, the aim of our research was to investigate whether Pb could activate autophagy to play a protective role against osteoblasts apoptosis. Our results indicated that PbCl2 induced autophagy and autophagic flux in MC3T3-E1 murine osteoblastic cell by RT-PCR, western blot, as well as fluorescence microscopy analysis of GFP-LC3, AO and MDC staining. Pb increased the apoptosis of osteoblasts, evidenced by western blot and Hoechst 33258 staining assessment. In addition, inhibiting autophagy by 3-MA further increased the osteoblasts apoptosis after Pb exposure, showed by flow cytometry and Hoechst 33258 staining. Furthermore, phosphorylation of mTOR and p70S6K was inhibited by Pb exposure, indicating that Pb might induce autophagy in osteoblasts via inhibiting mTOR pathway. Altogether, these evidence suggested that Pb exporsure promoted autophagy flux in osteoblasts. The activation of autophagy by Pb played a protective role in osteoblasts apoptosis, which might be mediated through the mTOR pathway.

Occupational high-grade lead exposure has been reduced in recent decades as a result of increased regulation. However, environmental lead exposure remains widespread, and is associated with severe toxicity implicated in human diseases. We performed oral intragastric administration of various dose lead acetate to adult Sprague Dawley rats to define the role of lead exposure in hematopoietic stem cells (HSCs) function, and to clarify its underlying mechanism. Lead acetate-exposed rats exhibited developmental abnormalities in myeloid and lymphoid lineages, and a significant decline in immune functions. It also showed HSCs functional decline associated with senescent phenotype with low grade lead acetate exposure or apoptotic phenotype with relative higher grade dose exposure. Mechanistic exploration showed a significant increase in reactive oxygen species (ROS) in the lead acetate-exposed CD90(+)CD45(-) compartment, which correlated with functional defects in cellular mitochondria. Furthermore, in vivo treatment with the antioxidant vitamin C led to reversion of the CD90(+)CD45(-) compartment functional decline. These results indicate that lead acetate perturbs the hematopoietic balance of adult HSCs, associated with cellular mitochondria defects, increased intracellular ROS generation.

To investigate the anti-aging effect of ginsenoside R1 in serial transplantation of hematopoietic stem cells and progenitor cells.HSC/HPC aging model in vivo was established through the Sca-1 (+) HSC/HPC serial transplantation of male donor mice that had been separated and purified by the magnetic-activated cell sorting method. The female recipient mice that had been radiated with lethal dose of 60Co gamma ray were divided into four groups: the control group, the aging group, the Rg1-treated aging group and the Rg1 anti-aging group. The expression of Sry genes in bone marrow cells of recipient mice was analyzed by fluorescence quantitative PCR, in order to determine the source of hematopoietic reconstruction cells, observe the survival time and the recovery of the hematology of peripheral blood, and study the reconstruction of the hematopoietic function of recipient mice, the hematopoietic recovery promoted by Rg1, the culture of CFU-Mix of hemopoietic progenitor cells, the cell cycle analysis and aging-related SA-beta-Gal staining analysis on biological characteristics of Sca-1 (+) HSC/HPC aging, and the effect of Rg1 in vivo regulation on Sca-1 + HSC/HPC aging.The hematopoietic reconstruction cells of female recipient mice were derived from male donor mice. With the serial transplantation, the 30-day survival rate and the hematology in peripheral blood of recipient mice decreased. Sca-1 (+) HSC/HPC showed aging characteristics: the ratio of cells in G0/G1 phase and the positive rate of SA-beta-gal staining increased, whereas the number of CFU-Mix decreased. Compared with the aging group of the same generation, Rg1 -treated aging group and Rg1 anti-aging group showed higher 30-day survival rate and WBC, HCT, PLT and CFU-Mix, and lower cell ratio in Sca-1 (+) HSC/HPC G0/G1 stage and positive rate of SA-beta-gal staining. The Rg1 anti-aging group showed more significant changes than the Rg1 -treated aging group.Ginsenoside Rg1 has the effect of delaying and treating Sca-1 (+) HSC/HPC aging during the serial transplantation. Rg1 's anti-aging effect is superior to its effect of treating aging.

We determined the levels of prenatal Hg exposure in Wujiang City, located in the southeast of Taihu Lake in China's Jiangsu Province, and analyze the relationship between prenatal exposure to Hg and neonatal anthropometry, including birth weight, body length, and head circumference. From June 2009 to July 2010, a total of 213 mother-infant pairs were enrolled. The geometric means of Hg levels in maternal hair, fetal hair, placentas, and cord blood were 496.76 μg/kg, 233.94 μg/kg, 3.58 μg/kg, and 1.54 μg/L, respectively. The Hg levels detected in our study were significantly lower than those reported by previous studies. In addition, no significant correlations were found between Hg levels in maternal hair, fetal hair, placenta, or cord blood and neonatal anthropometrics. Together, our findings may be important for understanding the effects of prenatal exposure to Hg on newborns' development and have implications concerning the recommended dose for Hg.

OBJECTIVE To observe the effect and mechanism of ginsenoside Rg1 in inducing senescence human leukemia K562 cell line. METHOD Proliferation of K562 cell line induced by Rg1 was detected by MTT colorimetric test for the purpose to screen optimal active concentration and time (20 micromol x L(-1) , 48 h). Impact of Rg1 on cell cycle was analyzed using flow cytometry. The percentage of staining positive cells was detected by SA-beta-Gal staining. The expressions of senescence-related genes such as p16, p53, p21, Rb, were detected by RT-PCR and the changes in ultramicro-morphology were observed by transmission electron microscopy. RESULT Rg1 can significantly inhibit the proliferation of K562 cells in vitro and arrest the cells in G2/M phase. The percentage of positive cells stained by SA-beta-Gal was dramatically increased (P < 0.05) and the expression of cell senescence-related genes were up-regulated. The observation of ultrastructure showed that cell volume increase, heterochromatin condensation and fragmentation, mitochondrial volume increase, lysosomes increase in size and number. CONCLUSION Rg1 can induce the senescence of leukemia cell line K562 and play an important role in regulating p53-p21-Rb, p16-Rb cell signaling pathway.

We determined the effects of low-level prenatal MeHg exposure on neuronal migration in the developing rat cerebral cortex using in utero electroporation. We used offspring rats born to dams that had been exposed to saline or various doses of MeHg (0.01 mg/kg/day, 0.1 mg/kg/day, and 1 mg/kg/day) from gestational day (GD) 11-21. Immunohistochemical examination of the brains of the offspring was conducted on postnatal day (PND) 0, PND3, and PND7. Our results showed that prenatal exposure to low levels of MeHg (0.1 mg/kg/day or 1 mg/kg/day) during the critical stage in neuronal migration resulted in migration defects of the cerebrocortical neurons in offspring rats. Importantly, our data revealed that the abnormal neuronal distribution induced by MeHg was not caused by altered proliferation of neural progenitor cells (NPCs), induction of apoptosis of NPCs and/or newborn neurons, abnormal differentiation of NPCs, and the morphological changes of radial glial scaffold, indicating that the defective neuronal positioning triggered by exposure to low-dose of MeHg is due to the impacts of MeHg on the process of neuronal migration itself. Moreover, we demonstrated that in utero exposure to low-level MeHg suppresses the expression of Rac1, Cdc42, and RhoA, which play key roles in the migration of cerebrocortical neurons during the early stage of brain development, suggesting that the MeHg-induced migratory disturbance of cerebrocortical neurons is likely associated with the Rho GTPases signal pathway. In conclusion, our results provide a novel perspective on clarifying the mechanisms underlying the impairment of neuronal migration induced by MeHg. (C) 2012 Elsevier Ireland Ltd. All rights reserved.