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Chinese Tajiks are an Indo‐Iranian‐speaking population in Xinjiang, northwest China. Although the complex demographic history has been characterized, the ancestral sources and genetic admixture of Indo‐Iranian‐speaking groups in this region remain poorly understood. We here provide the genome‐wide genotyping data for over 700 000 single‐nucleotide polymorphisms (SNPs) and mtDNA multiplex sequencing data in 64 Chinese male Tajik individuals from two dialect groups, Wakhi and Selekur. We applied principal component analysis (PCA), ADMIXTURE, f‐statistics, treemix, qpWave/qpAdm, Admixture‐induced Linkage Disequilibrium for Evolutionary Relationships (ALDER), and Fst analyses to infer a fine‐scale population genetic structure and admixture history. Our results reveal that Chinese Tajiks showed the closest affinity and similar genetic admixture pattern with ancient Xinjiang populations, especially Xinjiang samples in the historical era. Chinese Tajiks also have gene flow from European and Neolithic Iran farmers‐related populations. We observed a genetic substructure in the two Tajik dialect groups. The Selekur‐speaking group who lived in the county had more gene flow from East Asians than Wakhi‐speaking people who inhabited the village. These results document the population movements contributed to the influx of diverse ancestries in the Xinjiang region. [ABSTRACT FROM AUTHOR]

Based on data from 839 comparable sections (sites) of the national surface water environmental quality monitoring network from 2012 to 2020, the variation tendency of surface water environmental quality over the past nine years was analyzed. The results showed that the environmental quality of surface water in China has continuously improved, the proportion of Grade Ⅰ-Ⅲ water quality increased steadily, and the proportion of inferior Grade Ⅴ water quality decreased in succession. The annual average concentration of ammonia nitrogen, total phosphorus, and permanganate index all showed a decreasing trend annually; compared with those in 2012, the three indicator concentrations respectively declined 75.9%, 48.2%, and 17.5% by 2020. In Guangxi, Hainan, and Ningxia, the proportion of Grade Ⅰ-Ⅲ water quality sections was maintained at 100%, whereas Hubei and Jiangxi showed a consecutive decreasing trend, and the other provinces showed a consecutive increasing trend. In Guangxi, Hainan, Ningxia, Hunan, and Fujian, the proportion of inferior Grade Ⅴ water quality sections remained at 0, and the other provinces showed a decreasing trend yearly. The annual average concentration of total phosphorus in Guangxi and Jiangxi and the permanganate index in Hubei, Hainan, and Liaoning increased annually, whereas that in the other provinces decreased to varying degrees. The proportion of Grade Ⅰ-Ⅲ water quality sections in Ten Major basins showed a fluctuating upward trend. The proportion of inferior Grade Ⅴ water quality in the Zhejiang and Fujian Slice Rivers was maintained at 0, and the other river basins showed a fluctuating and declining trend. The annual average of the main pollution indicators all decreased to varying degrees. In 2020, 53% of 32 important lakes were eutrophic, which increased 12% compared to that in 2012. On the whole, surface water quality has generally improved in China during the past nine years; especially since the 13 th Five-Year Plan period, remarkable achievements have been made in the prevention and control of water pollution. However, there are differences among various provinces and basins, the improvement in water environmental quality is unbalanced and uncoordinated, water resources are distributed unevenly, and the eutrophication trend of lakes and reservoirs is not optimistic. In the future, water resources, water environment, and water ecology should be overall managed, and great attention should be focused on precise pollution control and ecological restoration of surface water.

Research on human glioma stem cells began early in the 21 st century and since then has become a rapidly growing research field with the number of publications increasing year by year. The research conducted by our diverse group of investigators focused primarily on cell culture techniques, molecular regulation, signaling pathways, cancer treatment, the stem cell microenvironment and the cellular origin and function of glioma stem cells. In particular, we put forward our view that there are inverse or forward transformations among neural stem cells, glial cells and glioma stem cells in glioma tissues under certain conditions. Based on the background of the progress of international research on human glioma stem cells, we aim to share our progress and current findings of human glioma stem cell research in China with colleagues around the world., Competing Interests: None declared

Aim: To evaluate αB-crystallin malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GPx) changes in X-ray irradiated rat lens., Methods: Eight-week-old Sprague-Dawley male rats received X-ray irradiation to the head with rest of the body protected. The exposure dose ranged from 2 to 25 Grays (Gy). The cataract status were examined by slit lamp and rated with "four-grade systems" post-irradiation. The lens MDA level, and the activities of SOD and GPx were measured in a short-term experiment post-irradiation, and αB-crystallin protein levels were quantified., Results: The lenses of normal control and the X-ray irradiated groups with the dose up to 10 Gy remained transparent throughout the experiment. The lens first appeared tiny scatters, and even lamellar opacities in the posterior capsule 45 days post-irradiation with the dose of 15 Gy, and progressed slowly to the advance stage of cataract; while, for the higher dose (25 Gy), the opacity of lens appeared much earlier, and progressed more rapidly to mature stage of cataract within 1 month. At the end of the observation (90 days post-irradiation), almost all lenses became complete opacity with the higher dose (25 Gy). The degree of lens opacity was rated accordingly. The lens MDA level was increased, and SOD and GPx activities were decreased with a dose-dependent manner post-irradiation. The αB-crystallin protein level was decreased dose-dependently at the end point of observation., Conclusion: Oxidative events and αB-crystallin may play important roles in the pathogenesis of cataract in X-ray irradiated rat lens.

Objective: To investigate the target cells and molecules with sodium valproate induced differentiation of human glioma cells., Methods: Nude mice bearing human glioma xenogenic graft subcutaneously were treated with sodium valproate. The expressions of HDAC1 and Tob genes of xenografts were analyzed with semiquantitative RT-PCR. The CD133+ cells (BTSCs) were isolated from glioma specimens by immunomagnetic sorting, and cultured in the medium containing FCS or in the serum-free medium supplemented with growth factors, respectively, followed by treatment with sodium valproate in vitro for 21 days. The cell surface markers were detected with flow cytometry and confocal microscopy., Results: Sodium valproate inhibited the growth of subcutaneous xenografs bearing on nude mice (P<0.05), and up-regulated the HDAC1 expression (P<0.01), down-regulated the Tob expression (P<0.05). The cell surface markers of BTSCs were detected by flow cytometry after sodium valproate treatment for 21 days. In the FCS group, the GFAP or beta-tubulin III positive cells increased significantly (P<0.01), but in the growth factor group, no statistical differences were observed in the GFAP or beta-tubulin III expression (P>0.05). The results of confocal microscopy indicated that the GFAP+ or beta-tubulin III+ cells coexpressed with Nestin., Conclusions: HDAC1 and Tob genes were the potential target molecules in reversion of the differential inhibition of human glioma cells with sodium valproate. The BTSCs undergoing the processes of differentiation were the target cells for sodium valproate.

Based on the measurement of the CO2 flux on the water-air interface of Taihu Lake by closed chamber technique from January 2003 to June 2005, variation characteristics of the CO2 flux on the water-air interface in Taihu Lake are analyzed. Diurnal variation of the CO2 flux on the water-air interface is obvious. The CO2 flux is -0.79 mg/(m2 x h) in spring, -4.89 mg/(m2 x h) in summer, -4.06 mg/(m2 x h) in autumn and -2.56 mg/(m2 x h) in winter. Taihu Lake is the sink of carbon monoxide. The CO2 flux gets larger in severer polluted area of the lake. Seasonal variation is not apparent in the algae type lake, but obvious in grass type lake. It is high in summer and autumn, and low in spring and winter. Correlative factors of CO2 flux on the water-air interface of Taihu Lake possibly include weather, solar radiation, wind velocity, temperature, pH, TA, Chla, TC, TN and TP.

Objective: To pursue the changes of cell morphology, expression of differentiation related markers, and proliferation cycles of brain tumor stem cells (BTSCs) after differentiation in vitro., Methods: Tumor stem cells of the line CD133(+) were obtained from two specimens from one clinical case with anaplasia ependymocytoma during operation, one specimen being obtained during the first operation and then second specimen being obtained during the second operation 6 months later on the recurrent tumor. CD133(+) cells were acquired by using magnetic sorting and then cultured to differentiate in medium containing 10% fetal bovine serum. The morphology of the cells was observed under phase contrast microscope. Cells were collected respectively before differentiation and 3, 7, 10, and 21 days after the differentiation. The cell surface markers such as CD133, nestin, glial fibrillary acidic protein (GFAP), and beta-tubulin III were detected with flow cytometry. Proliferation cycles were examined before differentiation and in the 7th day after differentiation. Normal neural stem cells (NSCs) obtained from fetal brain tissues were used as controls., Results: (1) The BTSCs were round shape at the beginning, then changed to short fusiform, polygon and long fusiform. Seven days later the cells reversed to short fusiform and round shape. The cells accumulated into cell spheres and floated in the culture medium again. While the NSCs differentiated along their routine rules. (2) Both the undifferentiated BTSCs and NSCs showed high level expression of CD133 and nestin. After differentiation the BTSCs expressed CD133 and nestin, the expression levels decreased first and then increased. The expression rates of CD133 and nestin were (3.65 +/- 0.17)% and (28.99 +/- 1.26)% in the 7th day, (14.63 +/- 1.16)% and (45.46 +/- 1.27)% in the 21st day. While the positive expression rate of GFAP was higher than that of beta-tubulin III. In the 10th day the NSCs under differentiation lost the expression of CD133 and nestin. The percentage of GFAP positive cells and beta-tubulin III positive cells were (88.94 +/- 1.23)% and (11.94 +/- 0.36)% respectively. (3) All undifferentiated BTSCs were hypodiploid. After differentiation majority of the BTSCs were hypodiploid or hyperdiploid, The percentages of S phase and G(2)-M phase cells in the BTSCs were higher than that in the NSCs. The cell composition of recrudescent BTSCs was more complex than that of the primary BTSCs. All NSCs were diploid whether differentiated or not. Most of the NSCs were G(0)-G(1) phase cells., Conclusion: The differentiation direction of BTSCs is quietly different from that of the NSCs. There is an obvious dysdifferentiation in BTSCs.

Objective: To isolate and culture tumor stem cells from glioma tissues obtained at surgical operation and to study their biological characteristics., Methods: Glioma tissues obtained from surgically resected specimens of 8 patients were fully chopped, trypsinized, and filtered to prepare single cell suspensions. The cells were cultured in serum-free medium with EGF, LIF and bFGF. CD133(+) cells were purified by magnetic cell sorting, and cultured continuously in vitro to obtain tumor cell spheres. Tumor stem cells of the 5th passage were induced to differentiate with 10% FBS, and expression of cell differentiation markers such as Nestin, MAP2, GFAP was evaluated with immunocytochemistry techniques., Results: CD133(+) cells were successfully separated and cultured from one anasplastic mixed astrocyte-ependymocyte type glioma specimen. These cells maintained a sphere-like growth status in vitro (3 months, 14 passages), and can self-renew, proliferate and conditionally differentiate into MAP2(+) and GFAP(+) cells. However, CD133(-) cells did not possess these properties., Conclusion: Glioma tissue contains tumor stem cells. Those cells can be cultured and passaged in vitro for a long term, and therefore to offer new approaches for studying cellular and molecular biology of glioma.