[Spatiotemporal Distribution and Source Analysis of Heavy Metals in Surface Sediments in Lake Ulansuhai Based on PCA-APCS-MLR Model].

To explore the spatial and temporal distribution characteristics of heavy metals in the surface sediments of lakes in cold regions during ice-sealing and non-ice-sealing periods, we analyzed the potential ecological risk degree and the pollution sources. A total of 20 sampling sites in Lake Ulansuhai in cold regions were collected from 2020 to 2021, and 120 surface sediment samples were collected during different periods. The contents of As, Cd, Cr, Cu, Ni, Pb, Zn, and Hg were determined. Correlation analysis, principal component analysis, and the absolute factor score-multiple linear regression (APCS-MLR) receptor model were used to trace the source of heavy metal pollution. The results showed that:① the distribution of heavy metals in lake surface sediments was different between the ice-sealing period and the non-ice-sealing period. The distribution of heavy metals during the ice-sealing period was higher in the north and lower in the south. Cd and Hg were mainly distributed in the central and southern lakes during the non-glacial period. ② Hg, Cd, and As were moderately polluted, and Ni was mildly polluted in the surface sediments of the lake. The overall performance was at a high risk level, and the pollution level during the non-ice-sealing period was higher than that during the ice-sealing period. The main environmental risk factors were Hg and Cd, which showed high risk and moderate risk, respectively. ③ The sources of heavy metals in lake surface sediments were mainly industrial sources from mining and transportation, agricultural sources, and natural sources. As, Ni, Pb, and Hg were mainly affected by industrial sources, with contribution rates of 62.67%, 75.31%, 77.47%, and 80.11%, respectively. The main sources of Cu and Zn were natural sources, and Cd was greatly affected by agricultural sources. The contribution rate was 81.57%. The source of Cr was mainly affected by natural factors, and the influence of human activities and unknown sources require further attention.

[Risk Assessment of Heavy Metals in Dust Fall Around Reservoirs in Typical Ecologically Fragile Areas and Traceability Based on APCS-MLR Model].

To assess the health risk status and pollution sources of heavy metals in the atmosphere of ecologically vulnerable areas, the surrounding area of Dahekou Reservoir in Xilingol League was selected as the study area. From 2021 to 2022, 12 monitoring points for atmospheric dust fall were collected for a period of one year. A total of 144 samples were collected to determine the contents of eight types of heavy metals, namely Cr, Ni, Pb, Cu, Zn, Mn, As, and Cd. The potential ecological index (Eri) and health risk assessment model were used to assess the risk level of atmospheric heavy metals on ecological security and human health. The analysis of enrichment factors, principal components, and the model of absolute principal component multiple linear regression (APCS-MLR) receptor were used to analyze the sources of heavy metal pollution qualitatively in the atmosphere of the study area. The results showed that:① the mean value of the comprehensive potential ecological risk of heavy metals in the annual atmospheric dust fall in the study area was at a high ecological risk, and only the Cd value was at a very high risk level among the heavy metals, whereas the remaining were at a slight risk. ② The results of the health risk showed that intake by hand, mouth, and skin contact were the main exposure routes, which led to non-carcinogenic and carcinogenic risks. Children were under non-carcinogenic and acceptable carcinogenic risks in different months. During those months, the main source of the risks was As. ③ Through enrichment factor analysis, principal component analysis, and APCS-MLR receptor model calculation, the results revealed that the proportion of wind-blown sources was the largest, accounting for 37.82%, and the contribution rates of coal combustion and traffic sources to Cu, Cd, Pb, and Zn were 73.01%, 40.22%, 70.31%, and 32.82%, respectively. The contribution rate of mining activities to As was 42.59%, while that of industrial sources of Cd was 22.01%; the contributions of other human activity sources of Cd, As, Pb, and Zn were 21.12%, 34.40%, 23.04%, and 32.15%, respectively.

[Effect of the Process of Returning Farmland to Forest in the Loess Hilly Area on Soil Fungal Communities].

The conversion of farmland to forest significantly affects soil bacterial communities in the Loess Plateau. However, how soil fungal communities respond to the conversion of farmland to forest is not very clear in this region. To illustrate the problem, the loess hilly area located in Jiajiayao, Youyu County, Shanxi Province was taken as the study area, and soil from farmland (growing corn and millet) and artificial forest (growing sea buckthorn and Caragana) were sampled. Based on 18S rRNA high-throughput sequencing, the effect of the conversion of farmland to forest on soil fungal communities was investigated. Ascomycota dominated (61.03%-78.06%) in both farmland and forest soil, followed by Mucoromycota (12.11%-17.13%) and Basidiomycota (6.15%-18.42%). The relative abundance of other fungal phyla, such as Chytridiomycota, was low. At the genus level, the conversion of farmland to forest significantly affected the abundance of Chaetomium, Mortierella, Fusarium, and Geoglossum. Plant pathogenic fungi belonging to Fusarium were enriched in farmland. The results of non-metric multidimensional scaling (NMDS) and analysis of similarity (ANOSIM) showed that the conversion of farmland to forest significantly affected soil fungal communities in the hilly area of the Loess Plateau. Differences in the community structure were closely related to changes in soil physicochemical properties. Available phosphorus was particularly the main driving factor affecting soil fungal communities. These results can provide scientific references for the ecological benefit evaluation of vegetation restoration in the loess hilly area.

[Water use characteristics of artificial sand-fixing vegetation on the southern edge of Hunshandake Sandy Land, Inner Mongolia, China]. / æµ‘å–„è¾¾å ‹æ²™åœ°å—ç¼˜äººå·¥å›ºæ²™æ¤è¢«æ°´åˆ†åˆ©ç”¨ç‰¹å¾.

We examined the characteristics of water use in typical tree species of arbor and shrub in Hunshandake Sandy Land, Populus cathayana and Salix gordejevii, in the different seasons, with the aim to provide theoretical basis for the structural optimization of the artificial shelterbelt. Samples of precipitation, soil water, groundwater and stem water of the two vegetation were collected, and their distribution characteristics of δD-δ18O were analyzed by hydrogen and oxygen stable isotope technology. The contribution rate of these potential water source to the arbor and shrub species were calculated using multi-source linear mixing model. The precipitation equation line in the study area was δD=7.84δ18O+9.12, while soil moisture lines in the dry and wet season were δD=3.56δ18O-41.28 and δD=4.30δ18O-42.02, respectively. The δD-δ18O of soil water and stem water in the two seasons were lower than the precipitation δD-δ18O, indicating that both of them were strongly affected by the evaporation. Soil water contents in the shallow layer were strongly affected by rainfall and evaporation, with substantial fluctuation. With the increases of soil depth, soil water content tended to be stable, and the hydrogen and oxygen isotope in each soil layer showed significant differences. In the dry season, P. cathayana mainly utilized soil water in 0-40 cm and 120-200 cm layers, with contribution rates of 50.2% and 31.5%, respectively. S. gordejevii mainly absorbed soil water in 20-40 cm and 60-100 cm layers, and the contribution rates were 53.2% and 22.9%, respectively. In the wet season, the greatest contribution of soil water to P. cathayana was mainly in the 0-40 cm soil layer, accounting for 72.8%. S. gordejevii was mainly in the 0-20 cm soil water, evenly utilized the deeper soil water and groundwater. Due to the differences in root depth and distribution of the arbor and shrub, their water use strategies differed in different seasons, which was conducive to the stability of the shelterbelt community and tree species coexistence in Hunshandake Sandy Land. We proposed that the mixed planting species with different root depth should be considered in the future planting of artificial shelterbelt, which would help rationally utilize water resources and maintain the stability of sandy land ecosystem.

[Relationship Between the Phytoplankton Distribution and Environmental Factors in Fenhe Scenic Spot of Taiyuan].

In order to explore the structural characteristics of phytoplankton community and the water quality and the water quality of the Fenhe scenic spot in Taiyuan, the species composition and the biomass of phytoplankton as well as their correlation with the environmental factors were monitored. The survey selected 9 sampling sites along the up and lower reaches in Fenhe scenic spot of Taiyuan, from Chaicun Bridge to Xiangyun Bridge. During the wet season (June-Octoher) in 2014, specimens were collected, qualitative and quantitative investigation on the algae and monitoring on physicochemical indexes of the water were studied. Meanwhile, the water quality was analyzed and evaluated combining all the physicochemical indexes and cell density. Correlation analysis and RDA were conducted to analyze the relationship of algal community structure and the environmental factors. The main results showed that the dominant phytoplanktons were Cyanophyta, Chlorophyta and Bacillariophyta. The algal biomass first increased and then reduced during the wet season, and the maximum value of hiomass occurred in July. There were many differences among different sampling points. The cell densities of phytoplankton were much higher in three central areas than the other sampling sites. Physical and chemical factors showed a variation tendency in time and space. Based on the results of RDA hetween phytoplankton cell densities and the physic-chemical parameters, the cell densities and the physic..chemical parameters had different correlations. The total cell density had significant positive correlation with dissolved oxygen, and negative correlation with COD. There were extremely significant positive correlations between diatom cell densities and water temperature, air temperature. But the diatom cell density was obviously negatively correlated with COD. It was distinct that the functions of the environment factors were different in temporal and spatial distrihution. The state index of comprehensive nutrition indicated that the total nitrogen content was beyond the standard in all sampling sites during the whole wet season. The water quality varied from oligotrophic to light eutrophic.

[Clinical trial of cellulose in treatment of functional constipation in children].

OBJECTIVE: To study the efficacy and safety of cellulose for the treatment of functional constipation in children. METHODS: A prospective, self-controlled, clinical trial using cellulose was conducted for 2 weeks in 34 children with functional constipation. The constipation symptoms and the characteristics of feces after the treatment were observed. RESULTS: The characteristics of feces and the constipation symptoms were improved significantly after the treatment. The total efficacy rate was 37% 3 days after treatment, 87% 7 days after treatment and 90% 14 days after treatment. The satisfactory rates of doctors and children's parents on the therapeutic effects were 57% and 63%, respectively. No adverse events, such as abdominal distention, pain or diarrhea, were observed during the treatment. CONCLUSIONS: Cellulose is effective and safe in the treatment of functional constipation in children.

[Regulative effects of Chinese herbs for nourishing yin and removing fire on gene expressions of estrogen receptor alpha, insulin-like growth factor-1 receptor, epithelial growth factor receptor and protein synthesis in epiphyseal growth plate of female pubertal rats].

OBJECTIVE: To investigate the effect of Chinese herbs for nourishing yin and removing fire (NYRF) on gene expressions of estrogen receptor alpha (ER alpha), insulin-like growth factor-1 receptor (IGF-1R) and epithelial growth factor receptor (EGFR) in the epiphyseal growth plate of the female pubertal rats. METHODS: The rats were randomly divided into the control group and the intervened group. Immunohistochemistry and realtime-PCR methods were used to measure the gene expression of ER alpha, IGF-1R and EGFR and their protein synthesis in epiphyseal growth plate. RESULTS: After being intervened with NYRF, the gene expressions of ER alpha and IGF-1R were down-regulated and their protein synthesis markedly reduced, while those of EGFR were unchanged. CONCLUSION: NYRF can modulate the development and maturation of bone by regulating the expressions of ER alpha and IGF-1R in the epiphyseal growth plate.

[Determination of four kinds of environmental endocrine disruptors in blood serum of precocious puberty patients by high performance liquid chromatography].

OBJECTIVE: This study was directed to the development of a simple and highly sensitive method for determination of four kinds of environmental endocrine discrupters (EEDs) in the serum of precocious puberty patients using reversed-phase HPLC. METHODS: The serum samples were extracted by n-hexane. The operating conditions were such as C18 column (4.6 mm x 250 mm 5 microm), methanol: H2O: trifuorocuetic acid (1000 : 50 : 1) as mobile phase at a flow rate of 1 ml/min. Using ultraviolet detector, DEHP and MEHP was determined with wavelength at 228 nm, p, p'-DDE was determined with wavelength at 238 nm. Fluorescence detector with the excitation and emission wavelength at 275 nm and 312 nm respectively were used to determine 4-NP. RESULTS: There was a good linear relationship between the concentrations of the analytes in serum and their peak areas in the range of for DEHP, for MEHP, for p, p'-DDE and for 4-NP. The detection limit of the method was 1 ng/ml for each of the analytes. Recoveries of serum samples were 96.84% - 103.44% for DEHP, 87.69% - 104.92% for MEHP, 87.6% - 109.89% for p, p'-DDE, 98.57% - 105.1% for 4-NP. CONCLUSION: The method is suitable for the determination of the four kinds of EEDs in serum. It is easy to dispose the samples. The volume of samples is decreased and the effect of detection is increased. The method is quicker and easier and could be widely used to determine these compounds. It is helpful for the clinical study of precocious puberty.

[Study on the level of environmental endocrine disruptors in serum of precocious puberty patients].

OBJECTIVE: To investigate the role of environmental endocrine disruptors (EEDs) in causing the precocious puberty. METHODS: The blood samples were collected from 79 cases of precocious puberty patients and 42 cases of normal children. The concentrations of 4-nonylphenol (4-NP), 1, 1-dichloro-2, 2, bis (p-chlorophenyl) ethylene (p, p'-DDE) and di-2-ethylhexyl phthalate (DEHP) in blood serum samples were measured by using reversed-phase high performance liquid chromatography (HPLC). The volume of uterus and ovary, the bone density, and the content of estradiol (E(2)) in serum were determined at the same time. The contents of EEDs in blood serums of precocious puberty and the indices of the target organs were analyzed by using of correlation and regression. RESULTS: In normal control group, p, p'-DDE was detected in all the blood samples (14.93 - 40.39 ng/ml), but 4-NP and DEHP were detected in some samples (ND -6.77 ng/ml, ND -17.61 ng/ml). The levels of 4-NP, p, p'-DDE and DEHP in blood serum in precocious puberty group were notably increased than that in control group (P < 0.01). In precocious puberty group, there was a positive correlations between the 4-NP in volume of uterus and the volume of ovary and the density of bone (r = 0.394, 0.286, 0.237, P < 0.01); p, p'-DDE and volume of uterus also showed a the positive correlation (r = 0.306, P < 0.01). The influencing extent of 4-NP was 1.3 times to that of the p, p'-DDE. CONCLUSION: The normal children and the children with precocious puberty should be all contaminated by EEDs, and the later be exposured to more EEDs. There might exist a close relationship between EEDs and the precocious puberty, and EEDs should be an important factor in causing the disease. Different kinds of EEDs might have different influencing extents to the target organs.

Ginsenoside Rg1-induced alterations in gene expression in TNF-alpha stimulated endothelial cells.

BACKGROUND: In China the ginseng root began to be used in medicine over 2000 years ago. Ginsenosides are the most important component isolated from ginseng. The authors investigated the effect of ginsenoside Rg1 on the spectrum of gene expression in the endothelial cells stimulated by TNF-alpha and further explored the potential molecular mechanism of endothelial protection by ginsenoside Rg1. METHODS: Nitric oxide (NO) production in the cultured human umbilical vein endothelial cells (HUVECs) was measured by using an NO assay kit. A home-made oligonucleotide microarray containing approximately 400 cardiovascular disease-related genes was constructed. The alteration of the spectrum of gene expression induced by ginsenoside Rg1 in HUVECs which were activated by TNF-alpha were detected by oligonucleotide microarray analysis. RESULTS: NO production in HUVECs was decreased significantly after TNF-alpha treatment, while pretreatment with ginsenoside Rg1 enhanced NO production in TNF-alphastimulated HUVECs. Ginsenoside Rg1 affected the expression levels of genes involved in vascular constriction, cell adherence, coagulation, cell growth and signal transduction in TNF-alphastimulated HUVECs. CONCLUSIONS: Ginsenoside Rg1 could enhance NO production and the expression of eNOS mRNA in TNF-alpha stimulated HUVECs. Ginsenoside Rg1 regulated sets of genes in endothelial cells and protected endothelial cells from TNF-alpha activation. Microarray analysis provided us with valuable insights into the atheroprotective mechanism by gingsenoside Rg1.

[Gene diagnosis of X-linked spondyloepiphyseal dysplasia tarda by linkage analysis and DNA sequencing].

OBJECTIVE: X linked spondyloepiphyseal dysplasia tarda (SEDL) is heritable osteochondrondysplasia characterized in affected males by disproportional short stature with short neck and trunk resulting from a growth defect of the vertebral bodies, accompanied by barrel chest and degenerative osteoarthropathy of hip joints. This progressive skeletal dysplasia is caused by the SEDL gene located approximately 100 kb centromeric of DXS16 at Xp22. The disorder usually manifests in late childhood without systemic complications, and generally female carriers of SEDL are asymptomatic. So the diagnosis of potential carriers and presymptomatic patients is almost impossible. This study aimed to establish methods of gene diagnosis for finding out potential carriers and presymptomatic patients. METHODS: The blood samples were collected from 21 individuals in a large Chinese pedigree with SEDL. Microsatellite marker DXS16 was selected for linkage analysis. In order to confirm the allele of DXS16 linked to the pathogenic SEDL gene, polymerase chain reaction (PCR) and polyacrylamide gel electrophoresis (PAGE) were used to examine the variability of the lengths of DXS16, and linkage analysis was performed for the diagnosis of potential carriers and presymptomatic patients. Then the pathogenic mutation of the SEDL gene in the family was identified by bi-directionally direct sequencing of PCR products amplified for each of the four coding exons as well as their exon/intron boundaries. The potential carriers and presymptomatic patients were also diagnosed in this way. RESULTS: Six young individuals (IV(14), IV(19), IV(21), IV(23), V(4), V(7))who wanted to know whether they were carriers or presymptomatic patients were diagnosed by linkage analysis. Four females of them (IV(14), IV(19), IV(21), V(7)) were determined being carriers because they carry the allele of DXS16 which links the pathogenic SEDL gene, and the other two (IV(23), V(4)) being normal individuals for their alleles of DXS16 linked with wild SEDL gene. DNA sequencing identified that the pathogenic mutation of SEDL gene in the family, which was a nucleotide substitution of the splice-acceptor site in intron 2, IVS2 -2 A-->C. This is a novel mutation in the SEDL gene. Four female individuals (IV(14), IV(19), IV(21), V(7)) carried the mutation; individuals IV(23) and V(4) carried the wild SEDL gene. The results of diagnosis of linkage analysis coincide completely with that of DNA sequencing. CONCLUSION: Linkage analysis is a simple, rapid and inexpensive gene diagnosis method for SEDL and its accuracy was the same as DNA sequencing. Each of linkage analysis and DNA sequencing can be used to diagnose SEDL, which is very helpful for finding potential carriers and presymptomatic patients.