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Isocitrate dehydrogenase 2 (IDH2) and glutamate dehydrogenase 1 (GLUD1) are key enzymes involved in the production of α-ketoglutarate (α-KG), a metabolite central to the tricarboxylic acid cycle and glutamine metabolism. In this study, we investigated the impact of IDH2 and GLUD1 on early porcine embryonic development following IDH2 and GLUD1 knockdown (KD) via double-stranded RNA (dsRNA) microinjection. Results showed that KD reduced α-KG levels, leading to delayed embryonic development, decreased blastocyst formation, increased apoptosis, reduced blastomere proliferation, and pluripotency. Additionally, IDH2 and GLUD1 KD induced abnormally high levels of trimethylation of lysine 20 of histone H4 (H4K20me3) at the 4-cell stage, likely resulting in transcriptional repression of embryonic genome activation (EGA)-related genes. Notably, KD of lysine methyltransferase 5C ( KMT5C ) and supplementation with exogenous α-KG reduced H4K20me3 expression and partially rescued these defects, suggesting a critical role of IDH2 and GLUD1 in the epigenetic regulation and proper development of porcine embryos. Overall, this study highlights the significance of IDH2 and GLUD1 in maintaining normal embryonic development through their influence on α-KG production and subsequent epigenetic modifications.

Damage to the development of porcine gametes and embryos caused by high temperatures (HT) is one of the main reasons for the decline in the economic benefits of the livestock industry. Zygotic genome activation (ZGA) marks the beginning of gene expression programs in mammalian pre-implantation embryos. In pigs, ZGA occurs at the 4-cell (4 C) stage, indicating that correct gene expression at this stage plays an important regulatory role in embryonic development. However, the effect of the HT environment on early porcine embryonic development and the RNA expression profile of ZGA remain unclear. In this study, we compared the RNA transcription patterns of porcine 4 C embryos under normal and HT conditions using RNA-seq and identified 326 differentially expressed genes (DEGs). These changes were mainly related to DNA polymerase activity, DNA replication, and nucleotidyltransferase activity. In addition, entries for reverse transcription and endonuclease activity were enriched, indicating that ZGA interfered under HT conditions. Further comparison of the experimental results with the porcine ZGA gene revealed 39 ZGA genes among the DEGs. KEGG and GSEA analysis showed that the oxidative phosphorylation pathway was significantly enriched and signaling pathways related to energy metabolism were significantly downregulated. We also found that NDUFA6 and CDKN1A were located at the center of the protein-protein interaction network diagram of the DEGs. In summary, HT conditions affect mitochondrial function and oxidative phosphorylation levels, and lead to changes in the expression pattern of ZGA in early porcine embryos, with its hub genes NDUFA6 and CDKN1A., (© 2024. The Author(s).)

G-protein-coupled receptor kinase 2 (GRK2) interacts with Gβγ and Gαq, subunits of G-protein alpha, to regulate cell signalling. The second messenger inositol trisphosphate, produced by activated Gαq, promotes calcium release from the endoplasmic reticulum (ER) and regulates maturation-promoting factor (MPF) activity. This study aimed to investigate the role of GRK2 in MPF activity during the meiotic maturation of porcine oocytes. A specific inhibitor of GRK2 (βi) was used in this study. The present study showed that GRK2 inhibition increased the percentage of oocyte arrest at the metaphase I (MI) stage (control: 13.84 ± 0.95%; βi: 31.30 ± 4.18%), which resulted in the reduction of the maturation rate (control: 80.36 ± 1.94%; βi: 65.40 ± 1.14%). The level of phospho-GRK2 decreased in the treated group, suggesting that GRK2 activity was reduced upon GRK2 inhibition. Furthermore, the addition of βi decreased Ca 2+ release from the ER. The protein levels of cyclin B and cyclin-dependent kinase 1 were higher in the treatment group than those in the control group, indicating that GRK2 inhibition prevented a decrease in MPF activity. Collectively, GRK2 inhibition induced meiotic arrest at the MI stage in porcine oocytes by preventing a decrease in MPF activity, suggesting that GRK2 is essential for oocyte meiotic maturation in pigs., (© 2024 Wiley‐VCH GmbH. Published by John Wiley & Sons Ltd.)

Methionine adenosyltransferase 2A (MAT2A) is an essential enzyme in the methionine cycle that generates S-adenosylmethionine (SAM) by reacting with methionine and ATP. SAM acts as a methyl donors for histone and DNA methylation, which plays key roles in zygotic genome activation (ZGA). However, the effects of MAT2A on porcine ZGA remain unclear. To investigate the function of MAT2A and its underlying mechanism in porcine ZGA, MAT2A was knocked down by double-stranded RNA injection at the 1-cell stage. MAT2A is highly expressed at every stage of porcine embryo development. The percentages of four-cell-stage embryos and blastocysts were lower in the MAT2A-knockdown (KD) group than in the control group. Notably, depletion of MAT2A decreased the levels of H3K4me2, H3K9me2/3, and H3K27me3 at the four-cell stage, whereas MAT2A KD reduced the transcriptional activity of ZGA genes. MAT2A KD decreased embryonic ectoderm development (EED) and enhancer of zeste homolog 2 (EZH2) expression. Exogenous SAM supplementation rescued histone methylation levels and developmental arrest induced by MAT2A KD. Additionally, MAT2A KD significantly increased DNA damage and apoptosis. In conclusion, MAT2A is involved in regulating transcriptional activity and is essential for regulating histone methylation during porcine ZGA., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Assisted reproduction technology (ART) procedures are often impacted by post-ovulatory aging (POA), which can lead to reduced fertilization rates and impaired embryo development. This study used RNA sequencing analysis and experimental validation to study the similarities and differences between in vivo- and vitro-matured porcine oocytes before and after POA. Differentially expressed genes (DEGs) between fresh in vivo-matured oocyte (F_vivo) and aged in vivo-matured oocyte (A_vivo) and DEGs between fresh in vitro-matured oocyte (F_vitro) and aged in vitro-matured oocyte (A_vitro) were intersected to explore the co-effects of POA. It was found that "organelles", especially "mitochondria", were significantly enriched Gene Ontology (GO) terms. The expression of genes related to the "electron transport chain" and "cell redox homeostasis" pathways related to mitochondrial function significantly showed low expression patterns in both A_vivo and A_vitro groups. Weighted correlation network analysis was carried out to explore gene expression modules specific to A_vivo. Trait-module association analysis showed that the red modules were most associated with in vivo aging. There are 959 genes in the red module, mainly enriched in "RNA binding", "mRNA metabolic process", etc., as well as in GO terms, and "spliceosome" and "nucleotide excision repair" pathways. DNAJC7 , IK , and DDX18 were at the hub of the gene regulatory network. Subsequently, the functions of DDX18 and DNAJC7 were verified by knocking down their expression at the germinal vesicle (GV) and Metaphase II (MII) stages, respectively. Knockdown at the GV stage caused cell cycle disorders and increase the rate of abnormal spindle. Knockdown at the MII stage resulted in the inefficiency of the antioxidant melatonin, increasing the level of intracellular oxidative stress, and in mitochondrial dysfunction. In summary, POA affects the organelle function of oocytes. A_vivo oocytes have some unique gene expression patterns. These genes may be potential anti-aging targets. This study provides a better understanding of the detailed mechanism of POA and potential strategies for improving the success rates of assisted reproductive technologies in pigs and other mammalian species.

Refreezing the remaining genetic resources after in vitro fertilization (IVF) can conserve genetic materials. However, the precise damage inflicted by repeated freezing and thawing on bovine sperm and its underlying mechanism remain largely unexplored. Thus, this study investigates the impact of repeated freeze-thaw cycles on sperm. Our findings indicate that such cycles significantly reduce sperm viability and motility. Furthermore, the integrity of the sperm plasma membrane and acrosome is compromised during this process, exacerbating the advanced apoptosis triggered by oxidative stress. Additionally, transmission electron microscopy exposed severe damage to the plasma membranes of both the sperm head and tail. Notably, the "9 + 2" structure of the tail was disrupted, along with a significant decrease in the level of the axonemal protein DNAH10, leading to reduced sperm motility. IVF outcomes revealed that repeated freeze-thaw cycles considerably impair sperm fertilization capability, ultimately reducing the blastocyst rate. In summary, our research demonstrates that repeated freeze-thaw cycles lead to a decline in sperm viability and motility, attributed to oxidative stress-induced apoptosis and DNAH10-related dynamic deficiency. As a result, the utility of semen is compromised after repeated freezing., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Society for Cryobiology. Published by Elsevier Inc. All rights reserved.)

Nobiletin is a natural flavonoid found in citrus fruits with beneficial effects, including anti-inflammatory, anti-cancer and anti-oxidation effects. The aim of this study was to investigate whether nobiletin improves mitochondrial function in porcine oocytes and examine the underlying mechanism. Oocytes enclosed by cumulus cells were cultured in TCM-199 for 44 h with 0.1% dimethyl sulfoxide (control), or supplemented with 5, 10, 25, and 50 μM of nobiletin (Nob5, Nob10, Nob25, and Nob50, respectively). Oocyte maturation rate was significantly enhanced in Nob10 (70.26 ± 0.45%) compared to the other groups (control: 60.12 ± 0.47%; Nob5: 59.44 ± 1.63%; Nob25: 63.15 ± 1.38%; Nob50: 46.57 ± 1.19%). The addition of nobiletin reduced the levels of reactive oxygen species and increased glutathione levels. Moreover, Nob10 promoted mitochondrial biogenesis by upregulating the protein levels of sirtuin 1 (SIRT1) and peroxisome proliferator-activated receptor-gamma coactivator 1α (PGC-1α). This resulted in an increase in the number of active mitochondria, mitochondrial DNA copy number, mitochondrial membrane potential, and ATP production, thereby enhancing mitochondrial function. The protein level of p53 decreased, followed by the phosphorylation of B-cell lymphoma 2, suggesting a reduction in mitochondria-mediated apoptosis in the Nob10 group. Additionally, the release of cytochrome c from the mitochondria was significantly diminished along with a decrease in the protein expression of caspase 3. Thus, nobiletin has a great potential to promote the in vitro maturation of porcine oocytes by suppressing oxidative stress and promoting mitochondrial function through the upregulation of the SIRT1/PGC-1α signaling pathway., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Objectives: To explore the clinical manifestations, endoscopic findings, histopathological changes, treatment, and prognosis of eosinophilic gastrointestinal disease (EGID) in children, with the aim of enhancing awareness among pediatricians about this condition., Methods: Data of 267 children with EGID were prospectively collected from January 2019 to July 2022 at Jiangxi Children's Hospital, Hunan Children's Hospital, and Henan Children's Hospital. The age of onset, symptoms, physical signs, laboratory examination results, endoscopic findings, histopathological changes, and treatment outcomes were observed., Results: Among the 267 children with EGID, the majority had mild (164 cases, 61.4%) or moderate (96 cases, 35.6%) clinical severity. The disease occurred at any age, with a higher prevalence observed in school-age children (178 cases). The main symptoms in infants were vomiting and hematemesis, while in toddlers, vomiting and bloody stools were prominent. Abdominal pain and vomiting were the primary symptoms in preschool and school-age children. Nearly half (49.4%) of the affected children showed elevated platelet counts on hematological examination, but there was no significant difference in platelet counts among children with mild, moderate, and severe EGID ( P >0.05). Endoscopic findings in EGID children did not reveal significant specificity, and histopathological examination showed no specific structural damage. Among them, 85.0% (227 cases) received acid suppression therapy, 34.5% (92 cases) practiced dietary avoidance, 20.9% (56 cases) received anti-allergic medication, and a small proportion (24 cases, 9.0%) were treated with prednisone. Clinical symptoms were relieved in all patients after treatment, but three cases with peptic ulcers experienced recurrence after drug discontinuation., Conclusions: Mild and moderate EGID are more common in children, with no specific endoscopic findings. Dietary avoidance, acid suppression therapy, and anti-allergic medication are the main treatment methods. The prognosis of EGID is generally favorable in children.

Background: Ketosis is one of the most frequent and costly metabolic disorders in high-producing dairy cows, and negatively associated with the health and reproductive performance of bovine. Ketosis is mainly caused by the accumulation of ketone body β-hydroxybutyric acid and its diagnosis is based on β-hydroxybutyrate (βHB) concentration in blood. Methods: In this study, we investigated the effects of βHB on bovine oocyte maturation in the concentration of subclinical (1.2 mM) βHB and clinical (3.6 mM). Results: The results showed βHB disrupted bovine oocyte maturation and development capacity. Further analysis showed that βHB induced oxidative stress and mitochondrial dysfunction, as indicated by the increased level of reactive oxygen species (ROS), disrupted mitochondrial structure and distribution, and depolarized membrane potential. Furthermore, oxidative stress triggered early apoptosis, as shown by the enhanced levels of Caspase-3 and Annexin-V. Moreover, 3.6 mM βHB induced the disruption of the pyruvate dehydrogenase (PDH) activity, showing with the decrease of the global acetylation modification and the increase of the abnormal spindle rate. Conclusion: Our study showed that βHB in subclinical/clinical concentration had toxic effects on mitochondrial function and PDH activity, which might affect energy metabolism and epigenetic modification of bovine oocytes and embryos., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Zhang, Guo, Zhan, Yuan, Min, Li, Liu, Wang, Zhao, Lu and Ma.)

Heat stress (HS) affects the development of porcine gametes and embryos negatively, induces the decrease of reproductive ability significantly, threatens global pig production. Ginsenoside Re (GRe), is a main bioactive component of ginseng, shows very specific anti-apoptotic, antioxidant and anti-inflammatory activities. To investigate the alleviating effect of GRe on the in vitro maturation of porcine oocyte under the HS, the polar body extrusion rate, intracellular levels of reactive oxygen species (ROS) and glutathione (GSH), ATP content, mitochondrial membrane potential (MMP) were assessed. For the current study, porcine cumulus-oocyte complexes (COCs) randomly divided into four groups: the control, GRe, HS and HS + GRe group. The results showed that HS inhibited the cumulus cell expansion and polar body extrusion rate, the levels of GSH and MMP, the ATP content, the gene expression of Nrf2 of porcine oocytes and the parthenogenetic activation (PA) embryo development competence, but GRe treatment could partly neutralize these adverse effects. Furthermore, HS increased the ROS formation and percentage of apoptosis, the gene expression of HSP90, CASP3 and CytoC of porcine oocytes, but GRe could weaken the effect on Cyto C and BAX expression induced by HS. Taken together, these results showed that the presence of GRe during in vitro maturation protects porcine oocytes from HS. These findings lay a foundation for GRe may be used as a potential protective drug to protect porcine oocytes against HS damage., (© 2022 Wiley-VCH GmbH.)

Tetrabromobisphenol (TBBPA) is the most widely used brominated flame retardant in the world and displays toxicity to humans and animals. However, few studies have focused on its impact on oocyte maturation. Here, TBBPA was added to the culture medium of bovine cumulus-oocyte complexes (COCs) to examine its effect on oocytes. We found that TBBPA exposure displayed an adverse influence on oocyte maturation and subsequent embryonic development. The results of this study showed that TBBPA exposure induced oocyte meiotic failure by disturbing the polar-body extrusion of oocytes and the expansion of cumulus cells. We further found that TBBPA exposure led to defective spindle assembly and chromosome alignment. Meanwhile, TBBPA induced oxidative stress and early apoptosis by mediating the expression of superoxide dismutase 2 (SOD2). TBBPA exposure also caused mitochondrial dysfunction, displaying a decrease in mitochondrial membrane potential, mitochondrial content, mtDNA copy number, and ATP levels, which are regulated by the expression of pyruvate dehydrogenase kinase 3 (PDK3). In addition, the developmental competence of oocytes and the quality of blastocysts were also reduced after TBBPA treatment. These results demonstrated that TBBPA exposure impaired oocyte maturation and developmental competence by disrupting both nuclear and cytoplasmic maturation of the oocyte, which might have been caused by oxidative stress induced by mitochondrial dysfunction.

In this study, we investigated an absorber based on a center-aligned tandem nanopillar array for ultra-broadband solar energy harvesting theoretically. A high-efficiency, omnidirectional absorber was obtained by introducing the center-aligned tandem nanopillar array embedded in an Al 2 O 3 dielectric layer. The multi-coupling modes at different wavelengths were interpreted. The strong absorption can be adjusted by changing the radii and heights of nanopillars. According to the simulation results, the average absorptance of the absorber exceeded 94% in the wavelength range from 300 nm to 2000 nm. In addition, the high-efficiency absorption was insensitive to the incident angle and polarization state. The research not only proposed an absorber which possesses a huge potential value for application areas, such as thermal photovoltaic systems, infrared detection, and isotropic absorption sensors, but also pointed out a new way to design an absorber with high efficiency in an ultrabroad wavelength range.

Objectives: To study the etiology and clinical features of children with ascites, so as to provide a basis for the diagnosis and treatment of ascites in children., Methods: The medical data of the children with ascites, who were hospitalized from January 1, 2010 to December 31, 2019, were retrospectively reviewed., Results: Among the 165 children with ascites, the male/female ratio was 1.53:1, and the mean age of onset was (6±4) years. The causes of ascites included surgical acute abdomen (39 children, 23.6%), infectious diseases (39 children, 23.6%), neoplastic diseases (27 children, 16.4%), hepatogenic diseases (18 children, 10.9%), pancreatitis (10 children, 6.1%), cardiogenic diseases (8 children, 4.8%), rheumatic immune diseases (6 children, 3.6%), and nephrogenic diseases (5 children, 3.0%). According to the age of onset, there were 33 infants, 24 young children, 30 preschool children, 41 school-aged children, and 37 adolescents. Surgical acute abdomen and hepatogenic diseases were the main causes of ascites in infants ( P <0.05). Neoplastic disease was the leading cause in young children ( P <0.05). Infectious diseases were the most common cause in adolescents ( P <0.05)., Conclusions: Surgical acute abdomen, infectious diseases, neoplastic diseases, and hepatogenic diseases are the common causes of ascites in children, and there are some differences in the leading cause of ascites between different age groups.

Biological cells in vivo typically reside in a dynamic flowing microenvironment with extensive biomechanical and biochemical cues varying in time and space. These dynamic biomechanical and biochemical signals together act to regulate cellular behaviors and functions. Microfluidic technology is an important experimental platform for mimicking extracellular flowing microenvironment in vitro. However, most existing microfluidic chips for generating dynamic shear stress and biochemical signals require expensive, large peripheral pumps and external control systems, unsuitable for being placed inside cell incubators to conduct cell biology experiments. This study has developed a microfluidic generator of dynamic shear stress and biochemical signals based on autonomously oscillatory flow. Further, based on the lumped-parameter and distributed-parameter models of multiscale fluid dynamics, the oscillatory flow field and the concentration field of biochemical factors has been simulated at the cell culture region within the designed microfluidic chip. Using the constructed experimental system, the feasibility of the designed microfluidic chip has been validated by simulating biochemical factors with red dye. The simulation results demonstrate that dynamic shear stress and biochemical signals with adjustable period and amplitude can be generated at the cell culture chamber within the microfluidic chip. The amplitudes of dynamic shear stress and biochemical signals is proportional to the pressure difference and inversely proportional to the flow resistance, while their periods are correlated positively with the flow capacity and the flow resistance. The experimental results reveal the feasibility of the designed microfluidic chip. Conclusively, the proposed microfluidic generator based on autonomously oscillatory flow can generate dynamic shear stress and biochemical signals without peripheral pumps and external control systems. In addition to reducing the experimental cost, due to the tiny volume, it is beneficial to be integrated into cell incubators for cell biology experiments. Thus, the proposed microfluidic chip provides a novel experimental platform for cell biology investigations., (© 2021 Wiley-VCH GmbH.)

Mine tailings, generated from the extraction, processing, and utilization of mineral resources, have resulted in serious acid mine drainage (AMD) pollution. Recently, scholars are paying more attention to two alternative strategies for resource recovery and ecological reclamation of mine tailings that help to improve the current tailing management, and meanwhile reduce the negative environmental outcomes. This review suggests that the principles of geochemical evolution may provide new perspective for the future in-depth studies regarding the pollution control and risk management. Recent advances in three recycling approaches of tailing resources, termed metal recovery, agricultural fertilizer, and building materials, are further described. These recycling strategies are significantly conducive to decrease the mine tailing stocks for problematic disposal. In this regard, the future recycling approaches should be industrially applicable and technically feasible to achieve the sustainable mining operation. Finally, the current state of tailing phytoremediation technologies is also discussed, while identification and selection of the ideal plants, which is perceived to be the excellent candidates of tailing reclamation, should be the focus of future studies. Based on the findings and perspectives of this review, the present study can act as an important reference for the academic participants involved in this promising field.

In November 2013, the total concentration of selected heavy metals in 43 urban dust samples, collected from two small-sized cities of industrial E'zhou and agricultural Huanggang, located in the southeastern Hubei province, central China, was detected quantitatively by flame atomic absorption spectrometric (FAAS) for ultimate purpose of pollution monitoring and risk evaluation. Results indicated that the mean concentrations exceeding their respective background values were observed for all the investigated metals, with the exception of Co (13.08mg kg -1 ) and Fe (38635.02mg kg -1 ) in Huanggang road dusts, whose average concentrations were close to the background levels. In comparison with the reference data reported from the selected cities worldwide, the urban road dusts were seriously polluted by heavy metals to diverse degrees. The contour distribution maps implied that obviously higher values zones were found between two different types of urban areas, located to both sides of the coastline of Yangtze River. Multivariate statistical analysis revealed that the enriched heavy metals had emanated from the combined effects of both natural sources and anthropogenic sources. Three pollution indices indicated that the riskiest element mainly comprising Cr, Ni, Cu, and Pb appeared to be the major contributors to the urban environmental pollution. Avoiding continuous damage requires, the riskiest metallic contaminants should be paid preferential attention to.

In order to investigate the characteristics and sources of elements in atmospheric aerosols (PM 10 ) measurements, samples were collected between April 2012 and February 2013 in Huangshi, a typical industrial city in the east of Hubei province, China. These samples were analyzed for seventeen elements using wavelength dispersive X-ray fluorescence spectrometry. In addition, the pollution characteristics of fourteen elements were analyzed by an enrichment factor (EF) method, and the sources of these elements were studied by a principal component analysis (PCA) and positive matrix factorization (PMF) method. The result from the EF indicated that the concentration of the seventeen elements in the PM 10 measurements varied from 0.01-9.83 μg·m -3 . The elemental concentration of S was the highest and Ni and V was the lowest during the monitoring period in Huangshi. Daily levels of Pb and Cd exceeded the annual reference values set by the National Ambient Air Quality Standard (GB3095-2012) by 36.4% and 89.1%, respectively. An analysis of EF showed that Ti, V, Mn, and Ni elements were mildly enriched, indicating they were affected by both natural and anthropogenic sources. Ca, Cr, and Ba elements were moderately enriched and Cu, Zn, Pb, Sn, Sb, and Fe were highly enriched or hyper accumulated, suggesting they are mainly sourced from human activities. There were four sources significantly contributing to the elements in the PM 10 measurement, which were determined using PCA and PMF analysis. These were soil and fugitive dust, coal combustion, industry exhausts, and motor vehicle emissions. The results of the two models supported each other and had good consistency.

The surface water and surface sediments were collected from Daye Lake in April 2014. The concentrations of heavy metals were determined by atomic absorption spectroscopy. The pollution potential health risk and ecological risk of heavy metals in water and sediment were assessed by the health risk assessment model and the potential ecological risk index method. The results showed that the concentrations of the heavy metals (Ni, Cd, Cu and Pb) was 49.27 μg·L -1 , 2.19 μg·L -1 , 12.18 μg·L -1 , 12.13 μg·L -1 (water) and 78.46 mg·kg -1 , 77.13 mg·kg -1 , 650.13 mg·kg -1 and 134.22 mg·kg -1 (sediment). Enrichment coefficient indicated that the enrichment of Cd, Cu and Pb was more serious, especially the accumulation of Cd was the most obvious. Compared to typical lakes in China, the contents of heavy metals in water and sediment were relatively high. The spatial pollutant distribution of the heavy metals in water and sediment all presented that the concentrations of the heavy metals were relatively higher in east and west of Daye Lake, relatively more uniform in the middle, and their origins were mainly from human activities. The results of environmental risk indicated that the carcinogens and chemical non-carcinogens health risk values of heavy metals by drinking water pathway were 9.77E-08~1.63E-05a -1 . Therefore, the pollution of Ni and Cd should be the primary control target for environmental health risk management. The descending order of pollution degree of four metals in sediment was Cd> Cu> Pb> Ni, and Cd was the main contributor of the potential ecological risk elements.

8 surface sediments and 8 water samples were collected from the Daye Lake in August 2015.The 16 kinds of EPA control polycyclic aromatic hydrocarbons (PAHs) were analyzed by GC-MS.The results showed that the PAHs concentrations of surface sediments and water ranged from 35.94 ng·g -1 to 2032.73 ng·g -1 and from 27.94 ng·L -1 to 242.95 ng·L -1 ,with average contents of 940.61 ng·g -1 and 107.77ng·L -1 ,respectively.The distribution of PAHs in surface sediments indicated that the contents in the center samples were higher than those in the bank samples,but the water showed nearly the opposite tendency.The 4-5 rings high molecular weight PAHs were the main components in the surface sediments,and the 2,4 and 5 rings PAHs were given priority in water.Compared with the other domestic and oversea lakes,the PAHs pollution of the Daye Lake was at a moderate level.Source apportionment showed that the PAHs in surface sediments and water from the Daye Lake came from the combustion source,HWM-PAHs were the dominant part of the PAHs in the sediment,reflecting the sediment PAHs pollution under the effects of mining and smelting over a long period;All monomer PAHs and total PAHs content in sediment did not exceed the ERM and FEL limiting values,showing that there was no particularly serious ecological risk caused by PAHs in the surface sediments from the Daye Lake;the incremental lifetime cancer risks assessment showed that the uptake risk of PAHs in Daye Lake water through the ingestion and dermal absorption were both in the acceptable range recommended by the USEPA,but all sites had higher risk than the acceptable risk level recommended by the Sweden environmental protection agency and Royal society.The pollution of seven carcinogenic PAHs needs prevention and control.

Bioaerosols of university dormitory can spread through air and cause a potential health risk for student staying in indoor environment. To quantify the characteristics of bioaerosols in indoor environment of university dormitory, concentration and size distribution of culturable bioaerosols were detected during the plum rain period, the correlations of culturable bioaerosol with concentration of particulate matter, the ambient temperature and relative humidity were analyzed using Spearman's correlation coefficient and finally the changes of size distribution of culturable bioaerosol caused by activities of students were detected. The results showed that the mean concentrations of culturable airborne bacteria and fungi were (2133 +/- 1617) CFUm' and (3111 +/- 2202) CFU x m(-3). The concentrations of culturable airborne bacteria and fungi exhibited negative correlation with PM1, PM2.5, and PM10, respectively. The respirable fractions of bacteria exhibited positive correlation with PM2.5, and the respirable fractions of fungi exhibited significant positive correlation with PM10. Ambient temperature had positive correlation with culturable airborne bacteria and fungi, and relative humidity had negative correlation with culturable airborne bacteria and fungi. In the afternoon, concentrations of culturable airborne fungi in indoor environment of university dormitory significantly increased, and the size distribution of culturable hioaerosols was different in the morning and afternoon.

Sea cucumber (Stichopus japonicus) autolysis during transportation and processing is a major problem and the specific proteinases responsible for autolysis have not yet been identified. In the present study, a 34 kDa serine proteinase (SP) was isolated to high purity from sea cucumber intestinal tract by a series of column chromatographies. Peptide mass fingerprinting revealed that six peptide fragments were identical to a proprotein convertase subtilisin/kexin type 9 preproprotein from sea cucumber A. japonicus. The enzyme hydrolyzed gelatin effectively at pH 6.0-9.0 and 35-40 °C, and the enzyme activity was strongly inhibited by SP inhibitors. Sea cucumber collagen was hydrolyzed significantly by purified SP at 37 °C and more gradually at 4 °C, suggesting that SP may be involved in autolysis. In addition, the SP gene that codes for 377 amino acid residues was cloned into an E. coli expression vector and expressed in vitro. A polyclonal antibody against rSP was prepared and found to react specifically against both rSP and endogenous SP, which may prove useful for future studies on the physiological functions of SP.

Matrix metalloproteinases (MMPs) play essential roles in the metabolism of animal collagen while few reports are available for MMPs in aquatic animals. In this study, we report the complete sequence of matrix metalloproteinase-2 (MMP-2) gene from common carp (Cyprinus carpio) skeletal muscle. The full-length cDNA of MMP-2 was 2792bp which contains an open reading frame of 1974bp, corresponding to a protein of 657 amino acid residues. Based on the structural feature of MMP-2, the gene of the catalytic domain containing 351 amino acid residues was cloned and expressed in Escherichia coli. SDS-PAGE showed that the truncated recombinant MMP-2 (trMMP-2) with molecular mass of approximately 38kDa was in the form of inclusion body. The trMMP-2 was further purified by immobilized metal ion affinity chromatography. After renaturation, similar to native MMP-2, the trMMP-2 exhibited high hydrolyzing activity toward gelatin as appeared on gelatin zymography and optimal activity was at pH 8.0 and 40°C. The activity of the trMMP-2 was completely suppressed by metalloproteinase inhibitors, including EDTA, EGTA and 1,10-phenanthroline while other proteinase inhibitors did not show any inhibitory effect. Divalent metal ion Ca(2+) was necessary for the gelatinolytic activity, suggesting it is a calcium-dependent metalloproteinase. Moreover, the trMMP-2 effectively hydrolyzed native type I collagen at 37°C and even at 4°C, implying its potential application value as a collagenase for preparation of biologically active oligopeptides., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The development of western China in the past decade has led to increased discharges of wastewater and river pollution. The Wei River is the largest tributary of the Huang He River, but its geochemistry has not been thoroughly investigated. Sixty-three bed-surface sediment samples were collected from the Wei and analyzed for 24 elements by WDXRF; objectives for the study were to investigate the geochemical properties of the sediments; identify sources, and assess pollution levels and environmental risks. Major and trace element concentrations were comparable with those in other large rivers in China, but potentially hazardous trace elements (PHTEs) were lower than in the Yangzi or Pearl Rivers; most likely due to dilution of contaminants by the large sand inflows into the Wei and a lower level of industrialization. Nonetheless, pollution and risk analyses demonstrate slight contamination of Cr, Mn, Nb, Ni and Zn, moderate contamination of Cu and Pb, and strong contamination of As at some locations. Adverse biological effects from Ni and Cu are possible and are likely from As. Statistical and spatial analyses indicate that agriculture runoff and industrial wastewater discharge contribute to the contamination of this river. A comprehensive environmental management strategy, realistic national standards for wastewater discharge, and rigid enforcement are needed to address river pollution in China.

Objective: To investigate the status of job burnout in traditional Chinese medicine (TCM) doctors and explore the effect of occupational commitment on job burnout., Methods: A test of occupational commitment and job burnout was carried out in 507 TCM doctors with occupational commitment questionnaire and Maslach Burnout Inventory-Human Services Survey (MBI-HSS)., Results: The age group of < 30 years scored lowest (2.352 +/- 0.660) in personal accomplishment compared with 30 years old group and 40 years old group [(2.136 +/- 0.704) and (2.127 +/- 0.628) respectively] (P < 0.01). The score of emotional exhaustion and depersonalization increased with educational levels. There was significantly negative correlation between job burnout and occupational commitment (P < 0.01). Occupational commitment had significant effect on job burnout (P < 0.01). Occupational trouble commitment was a major predictor for emotional exhaustion (P < 0.01). Professional self-efficacy commitment was a major predictor for depersonalization (P < 0.01). Affective commitment was a major predictor for personal accomplishment (P < 0.01)., Conclusion: Occupational commitment is a good predictor for job burnout. Improving occupational commitment is an important measure to prevent job burnout.

Objective: To test the structure validity of an occupational commitment scale for traditional Chinese medical (TCM) practitioners., Methods: Based on in-depth interviews with 18 TCM practitioners and an open-ended questionnaire survey of 67 TCM practitioners, an occupational commitment scale was developed. The questionnaire was tested in 324 TCM practitioners and revised after an exploratory factor analysis (EFA). The revised questionnaire was tested again in another 507 TCM practitioners. A measurement model (structural equation model) by confirmation factor analysis (CFA) was used to confirm the construct validity of the questionnaire. The occupational change intention was used to verify the criterion-related validity of the questionnaire. The reliability of the questionnaire was tested with Cronbach's alpha coefficient., Results: The EFA indicated that the occupational commitment scale consisted of four components from 13 items. The cumulative contribution of the four components reached 61.437%. The factor loading of each item attached to the relevant common factor ranged from 0.591 to 0.861. The CFA indicated a good fit of construct, with 1.79, 0.039, 0.97, 0.97, 0.98, and 0.72 fit index for chi2/ df, RMSEA, GFI, NNFI, CFI, and PNFI respectively. The occupational change intention correlated with the componets of occupational commitment negatively (P < 0.01). The Cronbach's alpha coefficients of the questionnaire and the four components ranged from 0.602 to 0.847., Conclusion: The occupational commitment scale for TCM practitioners has a valid structure of four dimensions, measuring affective commitment, limited alternatives commitment, professional self-efficacy commitment and occupational risk commitment. The questionnaire is valid and reliable.

Objective: This study is purposed to explore the relationship between aggressively driving behavior and functional polymorphism in the promoter region of the monoamine oxidase-A (MAOA) gene., Methods: A total of 348 automobile drivers were investigated with Deffenbacher's driver anger scale, driving vengeance questionnaire (DVQ) and driver aggression behavior questionnaire. Eighty-eight drivers were selected as more, medium and less aggressive group, each. Polymerase chain reaction (PCR) and 2.5% agarose gel electrophoresisi were adopted to detect the polymorphism of functional 30 bp-uVNTR in the promoter region of the X-chromosomal MAOA gene and their frequencies of varied genotypes were estimated., Results: Two alleles with 3 and 4 repeats of 30 bp-uVNTR were detected in the drivers. Among the more aggressive group, number of the allele with 3 repeats of 30 bp-uVNTR (63/88) was significantly more than that with 4 repeats (25/88) (chi(2) = 10.21, P < 0.01), and number of the allele with 4 repeats of 30 bp-uVNTR was more in the less aggressive group, indicating that persons with allele of 3 repeats of 30 bp VNTR were more aggressive in their driving than those with 4 repeats., Conclusions: Aggressively driving behavior in drivers possibly related to their functional MAOA-uVNTR polymorphism. Effect of the gene on aggressively driving behavior should be further studied.

Objective: To investigate the differences in serum biochemistry between specific pathogen-free (SPF) and conventional aged Wistar rats., Methods: Coulter-JT Analyzer was used to measure the values of serum biochemistry in the two grades of rats., Results: The serum levels of alanine aminotransferase (ALT), total protein (TP), alkaline phosphatase (ALP), total cholesterol (TC), triglyceride (TG), blood urea nitrogen (BUN), creatinine, Fe, P, glucose, uric acid (UA), and low density lipoprotein (LDL) were very significantly different between male and female Wistar rats of either conventional or SPF grade (P<0.01), which also had significant difference in albumin, lactate dehydrogenase (LDH) and apolipoprotein B (ApoB) (P<0.05). Between male aged Wistar rats of the two grades, the differences of TP, albumin, albumin/globulin (A/G) ratio, TC, TG, blood glucose, ApoA1, ApoB, UA, high-density lipoprotein (HDL), LDL, and glutamic oxalacetic transaminase (GOT) were very significant (P<0.01), with also significant differences in ALT, Fe, Mg (P<0.05). Between the female rats of the two grades, the serum levels of ALT, TP, albumin, A/G ratio, ALP, TG, BUN, creatinine, Fe, ApoA1, APOB, HDL, LDL, and bile acids were very significantly different (P<0.01), and Mg was significantly different (P<0.05)., Conclusion: Different microbiological profiles affect serum biochemistry of aged Wistar rats.

Objective: To find out the relationship of traffic accidents with life events, driving stress, aggressive driving, etc., Methods: A total of 905 automobile drivers were investigated with life events scale (LES), general driver stress questionnaire, driver behavior inventory and accidents experience, etc., Results: The scores of life events, driving stress, and aggressive driving in accident drivers (21.79 +/- 14.10, 23.81 +/- 11.86, 9.42 +/- 8.25 respectively) were higher than those in nonaccident drivers (16.82 +/- 8.45, 20.09 +/- 10.63, 5.66 +/- 7.54) (P < 0.01). The number of vehicle accidents was significantly correlated with the scores of LES, driving stress, driver's aggressive behavior, drowsy driving, weekly time of driving, drinking index (P < 0.05). A logistic analysis (Forward:LR) showed that the driving hour, drowsy driving, aggressive driving, and drinking index were closely related with traffic accidents (P < 0.01)., Conclusion: Life events, driving stress and aggressive driving of the drivers are important factors related to traffic accidents.

This paper mainly reviewed sustained +Gz acceleration-induced pathologic changes in various organ systems. Some of them are reversible and some may result in damage. Degree of the pathologic changes are related to G levels, G onset rates, duration of G exposure and individual difference factors. With raise of aircraft performance, acceleration problem is becoming more and more serious. Aviation medical workers should pay good attention to these changes and the use of high performance anti-G measures in order to ensure safety and performance of the pilots.

Objective: The purpose of this study was to attempt to simulate the push-pull maneuver on a single-axis human centrifuge using lower body positive pressure (LBPP), and to observe the effect of the push-pull maneuver on +Gz tolerance., Methods: Six volunteers participated in the experiment. They were subjected to LBPP of up to 300 mm Hg for 1 min. Blood pressure (BP) and heart rate (HR) were monitored before, during and after LBPP. Immediately after LBPP, +Gz tolerance was measured on a human centrifuge., Results: During LBPP, systolic BP (SBP) and diastolic BP (DBP) increased significantly, mean arterial pressure (MAP) increased but not significantly, and HR decreased significantly. After LBPP, SBP and MAP decreased significantly, while DBP and HR decreased but not significantly. In all subjects, +Gz tolerance decreased after LBPP. The decreased value was 0.70 +/- 0.06 G, maximum 1.0 G and minimum 0.5 G., Conclusion: The push-pull maneuver can be simulated on a single-axis human centrifuge using LBPP. The physiologic effects of LBPP were similar to those of -Gz. We observed that +Gz tolerance decreased after LBPP, which confirmed the push-pull effect from the experiment.

Objective. To sum up the experiences and to find the regularity of centrifuge examinations. Method. The data of nine years of centrifuge examination (from 1988 to 1996) of pilots who suffered from black out or LOC frequently were analyzed. Result. There were totally 492 times centrifuge examinations. First centrifuge examination included 229 pilots, 49 qualified, 180 unqualified. Second centrifuge examination included 263 pilots, 50 qualified, 213 unqualified. The pilots were all male. The average age of first centrifuge examination was 29.27 +/- 4.87 years. Average flying time was 1015.24 +/- 131.89 h. 68.7% of their plane was JJ-6 or above. Conclusion. Most pilots undergoing centrifuge examination these nine years were 26-35 year old, and had flown for 601-1200 h. The planes they flew are mostly high-performance fighter aircraft. Close attention must be paid to pilots under similar condition by the flight surgeon. It is recommended that the special equipment of G-tolerance training should be added to the fighter aircraft units.

Objective: System of pressure breathing for +Gz (PBG) has been incorporated into service in the high performance fighter aircraft, but there were significant differences among PBG pressure schedules used in different countries. The purpose of this study was to define an optimal pressure schedule in PBG system., Method: Five male subjects wearing GZ-2 anti-G suit and medium-sized bladder vest, plus PBG with 1.6, 2.4, and 3.2 kPa/G pressure schedules, respectively, were exposed to rapid onset (3.0 G/s) centrifuge +Gz runs. +Gz protection of PBG with each of the three pressure schedules were measured and the subjective ratings were collected., Result: The +Gz protection afforded by PBG with 1.60, 2.40, and 3.20 kPa/G pressure schedules were 2.00 +/- 0.31, 2.54 +/- 0.32, and 2.44 +/- 0.31 G, respectively. Subjective ratings showed that the PBG with 2.40 kPa/G pressure schedule was better than the other two., Conclusion: Our data suggest that a PBG pressure schedule of 2.4 kPa/G in PBG system is optimal. It not only assures the anti-G performance of PBG, but also reduces its side effects.

Background: The push-pull effect (PPE) has been suspected of causing many aircraft accidents. The perfusion and then withdrawal of cerebral blood during the PPE may change the state of the cerebral blood vessel., Hypothesis: During head-down tilt (HDT) cerebral vasoconstriction occurs in response to the elevated perfusion pressure to maintain cerebral blood flow, and during subsequent head-up tilt (HUT) the increased resistance of the cerebral blood vessel recovers slowly., Methods: Ten healthy male non-pilots were exposed to the following protocol using a rotating-table to simulate the push-pull maneuver: HUT (+1 Gz) for 1 min followed by transition to HDT (-1 Gz) 10 s followed by transition to HUT (+1 Gz) 1 min. Cerebral blood flow velocity and pulsatility indices in the left middle cerebral artery were continually measured with a transcranial Doppler (TCD) instrument., Results: Mean blood flow velocity (Vm) increased significantly by 10%, during the first 5 s of HDT, recovered to baseline during HDT 5 10 s, and remained unchanged during subsequent HUT. Systolic blood flow velocity (Vs) increased by 9% during HDT 5-10 s and 11% during HUT 0-5 s. Diastolic blood flow velocity (Vd) decreased by -9% during HDT 5-10 s, and -22% during HUT 0-5 s. Vs-Vd increased by 26% during HDT 5 10 s, and 41%, during HUT 0-5 s. Pulsatile indices (PI) and resistance index (RI) increased by 26%) and 15% during HDT 5-10 s, and by 40% and 27% during HUT 0-5 s, respectively. Vs, Vs-Vd, PI, and RI remained at the higher level, and Vd remained at the lower level to HDT 15-20 s., Conclusions: The results indicate that cerebral vasoconstriction occurred to prevent brain over-perfusion during HDT. During HUT, the elevated resistance of the cerebral vessel remained at the higher level for about 20 s, and may have worsened the cerebral perfusion from exposure to +Gz. This may be one of the mechanisms of PPE.

Objective: To investigate the change and regulation of cerebral circulation during rotating-table simulated push-pull maneuver., Method: A special rotating-table was used to simulate the push-pull maneuver. 10 healthy adults were subjected to a series of "head-up stand (+1Gz) 1 min head-down stand (-1Gz) 10 s and head-up stand (+1Gz) 1 min" changes. Cerebral blood flow velocity and pulsatility indices in the left middle cerebral artery were constantly measured with a TC2020TCD using Transcranial Doppler [correction of Transcanial Dopplor] instrument., Result: During 10 s head-down stand (-1Gz) systolic velocity (Vs) increased, diastolic velocity (Vd) decreased, and the pulsatility indices (PI and RI) increased significantly in the left middle cerebral artery. During subsequent head-up stand (+1Gz), these changes didn't resume immediately and maintained for at least 20 s., Conclusion: This result implied that the push-pull maneuver increased the resistance of the cerebral vessels, which might be one of the mechanisms of the push-pull effect.

Objective. To investigate the integrated protection capability afforded by a new type capstan anti-G equipment and anti-G straining maneuver, as a result we discussed the feasibility of protection for 8 G 10 s (rapid onset runs at 2 G/s) acceleration using an associated precept with the above both anti-G measures. Method. This study was accomplished using the human centrifuge with rapid onset at 2 G/s. First, we determined the relaxed +Gz tolerance of nine male aviation students, and then determined theirs most + Gz tolerance while thereinto the five aviation students using a new type capstan anti-G suit (NKH) + a new type anti-G valve (NKT) + L-1 anti-G straining maneuver (L-1) and the other four aviation students using a new type capstan counterpressure suit (NDC) + the new type anti-G valve (NKT) + L-1. Result. The most +Gz tolerance of five students was 8.80 +/- 0.27 G while using NKH + NKT + L-1 and was higher than their relaxed +Gz tolerance at 4.60 +/- 0.42 G (P< 0.01) and that the most +Gz tolerance of four students was 8.75 +/- 0.50 G while using NDC + NKT + L-1 and was higher than their relaxed +Gz tolerance at 4.50 +/- 0.46 G (P< 0.01). Conclusion. Pilot will be capable against the 8 G 10 s (rapid onset runs at 2 G/s) effectively using the new type capstan anti +/- G equipment and anti +/- G straining maneuver, and the provided precept has availability.

Objective: To demonstrate the effects of training on rectifying two high performance fight aircraft pilots with low +Gz tolerance., Methods: Anti-G straining maneuver (AGSM) and pressure breathing for +Gz (PBG) maneuver were trained during centrifuge +Gz stress., Results: After training, the +Gz tolerances with AGSM, and with PBG and anti-G suit were enhanced by 3.0 ~ 3.25 G and 2.75 ~ 3.0 G, respectively. The combined +Gz tolerance was higher than the relaxed +Gz tolerance by 4.25 ~ 4.5 G. Both two pilots had passed the 8 G 10 s SACM +Gz profile and reached the standard of training.

Three new chemicals, N-acyl glutamic acid as a stroma of cosmetics, an eye drops for myopia and 2, 4-dichloro-6-nitrophenylaminate (DCNP) as a new herbicide were evaluated with the eye irritation test. Japanese young rabbits were used, the right eye for test, the left as control. Before and after the test, the eye were stained with 2% sodium fluorescein and examined under slit-lamp microscope to observe the damage degree of cornea, and to record the reaction degree of conjunctiva and iris at the same time. Using the draize method to compare with three kinds of granding (method of bayard and hehir, of EPA and of NRC), the results were essentially the same. The severity of reaction to the eye irritation test is closely related to the kind of testing material and the concentration used and the length of time exposed. The standardization of eye irritation test is also discussed.

Crocidolite was found to be ubiquitous in a county in southwestern China. It had been widely used in the making of road pavement, stoves, wall paint, etc. The environmental levels of the asbestos fibers were determined. Of the 2175 local residents examined, 16 had asbestosis and 232 had pleural plaques. These clinical manifestations were noted mainly in patients over 50 years of age.

Fourteen compounds, differing in structure, mechanism of action, and primary target organs, were tested for cytotoxic responses in isolated hepatocyte suspensions prepared by a nonperfusion method from male Sprague-Dawley rats. The trypan blue exclusion test, measurement of enzyme activities in supernatants, and enzyme histochemistry were taken as indexes of cytotoxicity. All 14 compounds inhibited enzyme activities in hepatocytes. However, the activities of GOT and LDH in supernatants increased after exposure to the three haloalkanes, but decreased after exposure to the other chemicals (Na2CrO4, etc.). The number of dyed cells increased after exposure to six haloalkanes and the order of their relative toxicities in vitro was roughly in concordance with that of their in vivo hepatoxicities. These results indicate that isolated hepatocytes are useful for prescreening of potential hepatotoxicants; the so-called "enzyme leakage" should be replaced by "enzyme in supernatant" to reflect toxicities of different kinds of compounds; enzyme histochemistry is also a sensitive index in toxicological tests with isolated rat hepatocytes.