1.Effects of long-term noise exposure during sleep on liver circadian clock and lipid metabolism
Xinyao ZHANG ; Xiaojun SHE ; Yiming FU ; Bo FU ; Shuo WANG ; Mengzhu CHENG ; Rui WANG ; Bo CUI
Journal of Environmental and Occupational Medicine 2024;41(1):41-46
Background Long-term exposure to noise during sleep may has adverse effects on metabolic system, and liver lipid metabolism is closely related to circadian clock genes. Objective To investigate the effects of long-term noise exposure during sleep on liver circadian clock and lipid metabolism in mice and its related mechanism. Methods Twenty C57BL/6J male mice were randomly divided into two groups: a noise exposure group and a control group with 10 mice in each group. The mice in the noise exposure group were exposed to white noise at 90 dB sound pressure level (SPL) for 30 consecutive days, 8 h a day, from 9:00 to 17:00. The mice in the control group were exposed to background noise ≤40 dB SPL. After noise exposure, the animals were neutralized at 14:00 (ZT6) and 2:00 (ZT18), 5 animals at each time spot, and the liver tissues were collected. Total cholesterol and triglyceride in liver were determined by cholesterol oxidase method and glycerol phosphate oxidase method respectively. The expressions of circadian clock genes (Clock, Bmal1, Rev-erbα, and Rev-erbβ) and lipid metabolism genes (Srebp1c, Hmgcr, Fasn, Lxrα, Acc1, and Chrebp) in liver were detected by quantitative real-time PCR. Results Compared with the control group, the content of total cholesterol in liver in the noise exposure group increased by 48% (P<0.05) and the content of liver triglyceride increased by 61% (P<0.05) at ZT18. The mRNA expression levels of circadian clock genes Clock and Bmal1 in the noise exposure group was significantly increased at ZT18 and decreased at ZT6 (P<0.05). The mRNA expression level of Rev-erbα decreased at both ZT6 and ZT18 (P<0.05). The mRNA expression level of Rev-erbβ had no significant change at ZT6 and ZT18. The mRNA expression levels of liver lipid metabolism related genes Srebp1c, Hmgcr, Chrebp, and Lxrα in the noise exposure group were higher than those in the control group at ZT18 (P<0.05). The mRNA expression levels of Acc1 and Fasn showed no significant change at ZT6, then an upward trend at ZT18, but no significant difference between the two time spots (P>0.05). Conclusion Long-term noise exposure during sleep can cause circadian clock and lipid metabolism disorders in mice. Among them, suppression of key circadian clock genes may be associated with Rev-erbα-mediated upregulation of the nuclear receptors Srebp1c and Chrebp for lipid synthesis and deposition in the liver, resulting in lipid metabolism disorder.
2.Effects of long-term noise exposure during sleep on cognitive function and biological clock-related mechanisms in mice
Yiming FU ; Xinyao ZHANG ; Xiaojun SHE ; Yingwen ZHU ; Honglian YANG ; Xiujie GAO ; Bo FU ; Bo CUI
Journal of Environmental and Occupational Medicine 2024;41(2):119-124
Background Environmental noise pollution is serious, and there are few studies on the effects of long-term noise exposure during sleep on cognitive function and possible biological clock mechanism. Objective To explore the cognitive impairment induced by noise exposure during sleep in mice and possible biological clock mechanism, and to provide a theoretical basis for the protection against noise exposure. Methods Twenty male C57BL/6J mice were randomly divided into a control group and a noise-exposed group, 10 mice in each group. The noise-exposed group was exposed to sleep-period noise using a noise generator for 12 h (08:00–20:00) per day for a total of 30 d. The calibrated noise intensity was set at 90 dB. No intervention was imposed on the control group. At the end of the noise exposure, cognitive function of mice was examined using the new object recognition experiment and the open field test, and the hippocampal tissue damage of mice were evaluated by Nissl staining, ionized calcium binding adaptor molecule 1 (Iba1) immunofluorescence staining, and real-time fluorescence quantitative PCR for inflammatory factors and biological clock genes. Oxidative stress indicators in the hippocampus of mice were also detected by assay kit. Results After noise exposure during sleep period, the results of new object recognition experiment showed that the discrimination index of mice in the noise-exposed group was 0.06±0.04, which was significantly lower than that of the control group (0.65±0.13) (P<0.05). The results of open field test showed that the central activity distance of the noise-exposed group was (242.20±176.10) mm, which was significantly lower than that of the control group, (1548.00±790.30) mm (P < 0.05), and the central activity time of the noise-exposed group was (0.87±0.64) s, which was significantly lower than that of the control group, (6.00±2.86) s (P < 0.05). The Nissl staining results showed that compared with the control group, neurons in the hippocampus of the noise-exposed mice were shrunken, deeply stained, disorganized, and loosely connected. The immunofluorescence results showed that microglia in the hippocampus of the noise-exposed mice were activated and the expression of Iba1 was significantly increased compared with those of the control group (P<0.05). The real-time PCR results of showed that the mRNA levels of the biological clock genes Clock, Per2, and Rev-erbα were significantly increased compared with those of the control group (P<0.05), and the mRNA level of Per1 was significantly decreased compared with that of the control group (P<0.05); and the mRNA levels of IL-18, IL-6, iNOS, and NLRP3 in the hippocampal tissues of mice were significantly increased compared with those of the control group (P<0.05). The results of oxidative stress evaluation showed that compared with the control group, reduced glutathione content was significantly reduced in the noise-exposed group (P<0.001). Conclusion Noise exposure during sleep period can lead to the destabilization of biological clock genes in hippocampal tissues and trigger hippocampal neuroinflammation, which can lead to the activation of microglia and cause cognitive impairment in mice.
3.Effects of Amyloid Precursor Protein Intracellular Domain on Neurogenesis,Learning and Memory in Alzheimer's Disease Model Mice
Mei JIANG ; Xu DENG ; Zixiong QIU ; Xiaojun CUI ; Yuan FU
Journal of Sun Yat-sen University(Medical Sciences) 2024;45(5):683-693
[Objective]To investigate the effects of amyloid precursor protein intracellular domain(AICD)on neurogenesis,learning and memory in Alzheimer's disease(AD)model mice.[Methods]Immunofluorescence staining was used to detect the proliferation and differentiation of neural progenitor cells(NPCs)cultured in vitro,numbers of neural stem cells and neurons in embryonic cerebral cortex and adult hippocampal dentate gyrus(DG)derived from AICD transgenic mice.The morris water maze was applied to evaluate learning and memory ability of old AICD transgenic mice,and bioinformatics to predict and analyze the underlying molecular mechanisms.[Results]Immunofluorescence staining showed that NPCs,numbers of neural stem cells and neurons in embryonic cerebral cortex and hippocampal DG region were decreased(P<0.05),indicating that AICD inhibited neurogenesis in AD model mice at different periods.Morris water maze revealed that AICD increased escape latency of AD model mice,reduced numbers of platform crossing and neuron numbers in DG region(P<0.05).Bioinformatics results found 1 723 targets of AICD involved in the regulation of neurogenesis,learning and memory in the pathogenesis of AD,in which the key targets were TP53,CTNNB1,Akt1,EGFR,SRC,EP300,HDAC1,STAT3,HSP90AA1 and MAPK1.KEGG pathway annotation analysis showed that signaling pathways like PI3K-Akt and HIF-1 play a crucial role in the regulation of neurogenesis,learning and memory by AICD.[Conclusions]AICD could inhibit hippocampal neurogenesis in AD model mice,thus impair their learning and memory ability,which may be related to PI3K-Akt and HIF-1 signaling pathways.This study provides an experimental basis for further understanding the role of AICD in the pathogenesis of AD.
4.Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients (version 2024)
Yao LU ; Yang LI ; Leiying ZHANG ; Hao TANG ; Huidan JING ; Yaoli WANG ; Xiangzhi JIA ; Li BA ; Maohong BIAN ; Dan CAI ; Hui CAI ; Xiaohong CAI ; Zhanshan ZHA ; Bingyu CHEN ; Daqing CHEN ; Feng CHEN ; Guoan CHEN ; Haiming CHEN ; Jing CHEN ; Min CHEN ; Qing CHEN ; Shu CHEN ; Xi CHEN ; Jinfeng CHENG ; Xiaoling CHU ; Hongwang CUI ; Xin CUI ; Zhen DA ; Ying DAI ; Surong DENG ; Weiqun DONG ; Weimin FAN ; Ke FENG ; Danhui FU ; Yongshui FU ; Qi FU ; Xuemei FU ; Jia GAN ; Xinyu GAN ; Wei GAO ; Huaizheng GONG ; Rong GUI ; Geng GUO ; Ning HAN ; Yiwen HAO ; Wubing HE ; Qiang HONG ; Ruiqin HOU ; Wei HOU ; Jie HU ; Peiyang HU ; Xi HU ; Xiaoyu HU ; Guangbin HUANG ; Jie HUANG ; Xiangyan HUANG ; Yuanshuai HUANG ; Shouyong HUN ; Xuebing JIANG ; Ping JIN ; Dong LAI ; Aiping LE ; Hongmei LI ; Bijuan LI ; Cuiying LI ; Daihong LI ; Haihong LI ; He LI ; Hui LI ; Jianping LI ; Ning LI ; Xiying LI ; Xiangmin LI ; Xiaofei LI ; Xiaojuan LI ; Zhiqiang LI ; Zhongjun LI ; Zunyan LI ; Huaqin LIANG ; Xiaohua LIANG ; Dongfa LIAO ; Qun LIAO ; Yan LIAO ; Jiajin LIN ; Chunxia LIU ; Fenghua LIU ; Peixian LIU ; Tiemei LIU ; Xiaoxin LIU ; Zhiwei LIU ; Zhongdi LIU ; Hua LU ; Jianfeng LUAN ; Jianjun LUO ; Qun LUO ; Dingfeng LYU ; Qi LYU ; Xianping LYU ; Aijun MA ; Liqiang MA ; Shuxuan MA ; Xainjun MA ; Xiaogang MA ; Xiaoli MA ; Guoqing MAO ; Shijie MU ; Shaolin NIE ; Shujuan OUYANG ; Xilin OUYANG ; Chunqiu PAN ; Jian PAN ; Xiaohua PAN ; Lei PENG ; Tao PENG ; Baohua QIAN ; Shu QIAO ; Li QIN ; Ying REN ; Zhaoqi REN ; Ruiming RONG ; Changshan SU ; Mingwei SUN ; Wenwu SUN ; Zhenwei SUN ; Haiping TANG ; Xiaofeng TANG ; Changjiu TANG ; Cuihua TAO ; Zhibin TIAN ; Juan WANG ; Baoyan WANG ; Chunyan WANG ; Gefei WANG ; Haiyan WANG ; Hongjie WANG ; Peng WANG ; Pengli WANG ; Qiushi WANG ; Xiaoning WANG ; Xinhua WANG ; Xuefeng WANG ; Yong WANG ; Yongjun WANG ; Yuanjie WANG ; Zhihua WANG ; Shaojun WEI ; Yaming WEI ; Jianbo WEN ; Jun WEN ; Jiang WU ; Jufeng WU ; Aijun XIA ; Fei XIA ; Rong XIA ; Jue XIE ; Yanchao XING ; Yan XIONG ; Feng XU ; Yongzhu XU ; Yongan XU ; Yonghe YAN ; Beizhan YAN ; Jiang YANG ; Jiangcun YANG ; Jun YANG ; Xinwen YANG ; Yongyi YANG ; Chunyan YAO ; Mingliang YE ; Changlin YIN ; Ming YIN ; Wen YIN ; Lianling YU ; Shuhong YU ; Zebo YU ; Yigang YU ; Anyong YU ; Hong YUAN ; Yi YUAN ; Chan ZHANG ; Jinjun ZHANG ; Jun ZHANG ; Kai ZHANG ; Leibing ZHANG ; Quan ZHANG ; Rongjiang ZHANG ; Sanming ZHANG ; Shengji ZHANG ; Shuo ZHANG ; Wei ZHANG ; Weidong ZHANG ; Xi ZHANG ; Xingwen ZHANG ; Guixi ZHANG ; Xiaojun ZHANG ; Guoqing ZHAO ; Jianpeng ZHAO ; Shuming ZHAO ; Beibei ZHENG ; Shangen ZHENG ; Huayou ZHOU ; Jicheng ZHOU ; Lihong ZHOU ; Mou ZHOU ; Xiaoyu ZHOU ; Xuelian ZHOU ; Yuan ZHOU ; Zheng ZHOU ; Zuhuang ZHOU ; Haiyan ZHU ; Peiyuan ZHU ; Changju ZHU ; Lili ZHU ; Zhengguo WANG ; Jianxin JIANG ; Deqing WANG ; Jiongcai LAN ; Quanli WANG ; Yang YU ; Lianyang ZHANG ; Aiqing WEN
Chinese Journal of Trauma 2024;40(10):865-881
Patients with severe trauma require an extremely timely treatment and transfusion plays an irreplaceable role in the emergency treatment of such patients. An increasing number of evidence-based medicinal evidences and clinical practices suggest that patients with severe traumatic bleeding benefit from early transfusion of low-titer group O whole blood or hemostatic resuscitation with red blood cells, plasma and platelet of a balanced ratio. However, the current domestic mode of blood supply cannot fully meet the requirements of timely and effective blood transfusion for emergency treatment of patients with severe trauma in clinical practice. In order to solve the key problems in blood supply and blood transfusion strategies for emergency treatment of severe trauma, Branch of Clinical Transfusion Medicine of Chinese Medical Association, Group for Trauma Emergency Care and Multiple Injuries of Trauma Branch of Chinese Medical Association, Young Scholar Group of Disaster Medicine Branch of Chinese Medical Association organized domestic experts of blood transfusion medicine and trauma treatment to jointly formulate Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients ( version 2024). Based on the evidence-based medical evidence and Delphi method of expert consultation and voting, 10 recommendations were put forward from two aspects of blood support mode and transfusion strategies, aiming to provide a reference for transfusion resuscitation in the emergency treatment of severe trauma and further improve the success rate of treatment of patients with severe trauma.
5.Fermentative production of tetraacetyl phytosphingosine: a review.
Liuwei CUI ; Kaifeng WANG ; Xiaojun JI
Chinese Journal of Biotechnology 2023;39(6):2204-2214
Tetraacetyl phytosphingosine (TAPS) is an excellent raw material for natural skin care products. Its deacetylation leads to the production of phytosphingosine, which can be further used for synthesizing the moisturizing skin care product ceramide. For this reason, TAPS is widely used in the skin care oriented cosmetics industry. The unconventional yeast Wickerhamomyces ciferrii is the only known microorganism that can naturally secrete TAPS, and it has become the host for the industrial production of TAPS. This review firstly introduces the discovery, functions of TAPS, and the metabolic pathway for TAPS biosynthesis is further introduced. Subsequently, the strategies for increasing the TAPS yield of W. ciferrii, including haploid screening, mutagenesis breeding and metabolic engineering, are summarized. In addition, the prospects of TAPS biomanufacturing by W. ciferrii are discussed in light of the current progresses, challenges, and trends in this field. Finally, guidelines for engineering W. ciferrii cell factory using synthetic biology tools for TAPS production are also presented.
Sphingosine
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Ceramides
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Metabolic Engineering
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Synthetic Biology
6.Embedded 3D printing of porous silicon orbital implants and its surface modification.
Hong ZHAO ; Yilin WANG ; Yanfang WANG ; Haihuan GONG ; Feiyang YINJUN ; Xiaojun CUI ; Jiankai ZHANG ; Wenhua HUANG
Journal of Southern Medical University 2023;43(5):783-792
OBJECTIVE:
To prepare customized porous silicone orbital implants using embedded 3D printing and assess the effect of surface modification on the properties of the implants.
METHODS:
The transparency, fluidity and rheological properties of the supporting media were tested to determine the optimal printing parameters of silicone. The morphological changes of silicone after modification were analyzed by scanning electron microscopy, and the hydrophilicity and hydrophobicity of silicone surface were evaluated by measuring the water contact angle. The compression modulus of porous silicone was measured using compression test. Porcine aortic endothelial cells (PAOECs) were co-cultured with porous silicone scaffolds for 1, 3 and 5 days to test the biocompatibility of silicone. The local inflammatory response to subcutaneous porous silicone implants was evaluated in rats.
RESULTS:
The optimal printing parameters of silicone orbital implants were determined as the following: supporting medium 4% (mass ratio), printing pressure 1.0 bar and printing speed 6 mm/s. Scanning electron microscopy showed that the silicone surface was successfully modified with polydopamine and collagen, which significantly improved hydrophilicity of the silicone surface (P < 0.05) without causing significant changes in the compression modulus (P > 0.05). The modified porous silicone scaffold had no obvious cytotoxicity and obviously promoted adhesion and proliferation of PAOECs (P < 0.05). In rats bearing the subcutaneous implants, no obvious inflammation was observed in the local tissue.
CONCLUSION
Poprous silicone orbital implants with uniform pores can be prepared using embedded 3D printing technology, and surface modification obviously improves hydrophilicity and biocompatibility of the silicone implants for potential clinical application.
Animals
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Rats
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Swine
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Silicon
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Orbital Implants
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Endothelial Cells
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Porosity
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Silicones
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Printing, Three-Dimensional
7.Effects of high frequency flash stimulation on the capacity of learning memory and autonomous exploratory in young rats
Yu FU ; Xiujie GAO ; Xiaojun SHE ; Fangshan WU ; Qingfeng ZHAI ; Bo CUI ; Kun WANG
Chinese Journal of Behavioral Medicine and Brain Science 2023;32(3):203-209
Objective:To investigate the effects of 40 Hz and 70 Hz frequency flash stimulation on the ability of learning memory and autonomous exploratory in young rats.Methods:Twenty-seven SPF grade male SD rats aged 19-21 days were divided into control group (Ctr group), 40 Hz group and 70 Hz group with 9 in each group according to the random number table.The rats in Ctr group were not given flash stimulation, while rats in the 40 Hz and 70 Hz group were received 40 Hz, 70 Hz flash stimulation (1.5 h/d for 39 days), respectively.The Morris water maze experiment was used to assess the learning and memory ability of rats, and the open field experiment was used to evaluate the ability of autonomous exploratory of rats.Nissl staining was used to assess the morphology of Nissl bodies in the hippocampus CA1 region of the rats.The local field potentials (LFPs) collected from the primary visual cortex (V1 area) region by electrophysiological experiments was used to verify the synchronization of flash evoked neural oscillations.SPSS 23.0 software was used for statistical analysis.The repeated measures ANOVA and one-way ANOVA were used to analyze normal distribution measurement data, and LSD and Tamhane tests were used for further pairwise comparison.The Kruskal-Wallis test was used for non-normal distribution measurement data.Results:(1) The flash stimulation of 40 Hz and 70 Hz both can effectively caused synchronization of neural oscillations in the primary visual cortex of healthy young rats.(2) The results of repeated measures ANOVA analysis showed that there was no interaction effect of grouping and time in the escape latency of young rats in the Morris water maze positioning navigation phase( F=1.326, P>0.05 ). The escape latency had time main effect ( F=40.025, P<0.05), but no grouping main effect ( F=2.039, P>0.05). With the increase of learning days, the escape latency of young rats in each group decreased significantly.There was no interaction effect of grouping and time in the total distance of young rats ( F=2.029, P>0.079). It had time main effect ( F=32.052, P<0.05), but not grouping main effect ( F=2.390, P>0.05) on total distance.With the increase of learning days, the total distance of young rats in each group significantly shortened.On the 6th day of the Morris water maze experiment, there was no statistically significant difference among groups in terms of time in the target quadrant and the number of crossing platforms ( F=2.511, 0.802, both P>0.05). The results of the open field experiment showed that the total distance traveled in the center of young rats in each group was statistically significant ( H=8.935, P<0.05), the total distance traveled in the center in the 70 Hz group (3.80 (2.25, 6.93) m)was significantly longer than that in the 40 Hz group (0.80 (0.72, 1.46) m), P<0.05). The percentage of time spent in the center was statistically significant in the three groups ( H=11.050, P<0.05). Young rats in the 70 Hz group spent significantly higher percentage of time in the center(3.20(2.43, 8.30)) than those in the 40 Hz group (0.95 (0.37, 1.06 ), P<0.05 ). (3) Nissl staining results showed that Nissl bodies in the hippocampal CA1 area of young rats in Ctr, 40 Hz and 70 Hz group were all arranged neatly and tightly, no edema was found in the surrounding stroma, and no obvious inflammatory cell infiltration was found. Conclusion:70 Hz frequency flash stimulation may promote the ability of learning memory and autonomous exploratory of young rats.
8.A novel CRISPR/Cas9-hLacI donor adapting system for dsDNA-templated gene editing.
Baoxia MA ; Jieyu CUI ; Hongrun QIAN ; Xiaojun ZHANG ; Sen YANG ; Qijing ZHANG ; Yifan HAN ; Zhiying ZHANG ; Jiangang WANG ; Kun XU
Chinese Journal of Biotechnology 2023;39(10):4204-4218
During the gene editing process mediated by CRISPR/Cas9, precise genome editing and gene knock-in can be achieved by the homologous recombination of double-stranded DNA (dsDNA) donor template. However, the low-efficiency of homologous recombination in eukaryotic cells hampers the development and application of this gene editing strategy. Here, we developed a novel CRISPR/Cas9-hLacI donor adapting system (DAS) to enhance the dsDNA-templated gene editing, taking the advantage of the specific binding of the LacI repressor protein and the LacO operator sequence derived for the Escherichia coli lactose operon. The codon-humanized LacI gene was fused as an adaptor to the Streptococcus pyogenes Cas9 (SpCas9) and Staphylococcus lugdunensis Cas9 (SlugCas9-HF) genes, and the LacO operator sequence was used as the aptamer and linked to the dsDNA donor template by PCR. The Cas9 nuclease activity after the fusion and the homology-directed repair (HDR) efficiency of the LacO-linked dsDNA template were firstly examined using surrogate reporter assays with the corresponding reporter vectors. The CRISPR/Cas9-hLacI DASs mediated genome precise editing were further checked, and we achieved a high efficiency up to 30.5% of precise editing at the VEGFA locus in HEK293T cells by using the CRISPR/SlugCas9-hLacI DAS. In summary, we developed a novel CRISPR/Cas9-hLacI DAS for dsDNA-templated gene editing, which enriches the CRISPR/Cas9-derived gene editing techniques and provides a novel tool for animal molecular design breeding researches.
Humans
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Animals
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Gene Editing
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CRISPR-Cas Systems/genetics*
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HEK293 Cells
;
Homologous Recombination
;
DNA
9.Epidemic status of drinking water type endemic arsenic poisoning in Inner Mongolia Autonomous Region
Xiaojun WANG ; Zili CHANG ; Yanhong LI ; Yijun LIU ; Xuan WANG ; Zhenlin LI ; Chengxiang ZHAO ; Na CUI
Chinese Journal of Endemiology 2023;42(9):730-734
Objective:To investigate the epidemic scope and intensity of drinking water type endemic arsenic poisoning in Inner Mongolia Autonomous Region, as well as the prevalence and influencing factors, in order to provide scientific basis for precise formulation of prevention and control measures.Methods:A sampling survey was conducted on residents' drinking water in all villages and counties in Inner Mongolia Autonomous Region, water samples were selected according to different water supply methods (engineering water supply, physical and chemical water purification, and decentralized water supply), and the arsenic content was detected by atomic fluorescence method. The "Diagnosis of Endemic Arsenicosis" (WS/T 211-2015) was used for diagnosis of arsenic poisoning among all permanent residents who were exposing to or had been exposed to excessively high arsenic water, in order to search all the arsenic poisoning patients. Analyze the distribution of water arsenic in the historical disease areas and high arsenic villages and newly discovered high arsenic villages, and explore the prevalence and influencing factors of arsenic poisoning.Results:There were a total of 1 186 historical disease areas and high arsenic villages in Inner Mongolia Autonomous Region, mainly distributed in 28 banner counties of 8 league cities such as Bayannur, Hohhot and Baotou, with a regional distribution trend of more in the west and less in the east. At present, the water improvement rate in the historical disease areas and high arsenic villages was 98.23% (1 165/1 186), and the qualified rate of arsenic content in the water was 99.83% (1 184/1 186). The arsenic content in the water of historical disease areas and high arsenic villages ranged from 0.000 to 0.093 mg/L. Four newly discovered villages with arsenic exceeding standards had been found, and their arsenic content ranged from 0.074 to 0.142 mg/L. A total of 2 249 patients with arsenic poisoning were detected in the confirmed disease area/high arsenic villages, and the detection rate was 1.67% (2 249/134 645). The number of patients in Bayannur City was the largest with the most severe disease, accounting for 82.70% (1 860/2 249). Patients aged 60 and above accounted for 61.41% of the total cases (1 381/2 249), which was higher than other age groups (χ 2 = 840.52, P < 0.001). The detection rate of arsenic poisoning was higher in males than in females (χ 2 = 132.38, P < 0.001). There are statistically significant differences in the detection rate and severity distribution of arsenic poisoning patients among different water arsenic content groups(χ 2 = 1 557.85, 1 741.05, P < 0.001). Conclusions:After years of prevention and control work, the arsenic content in most historical disease areas and high arsenic villages in Inner Mongolia Autonomous Region is currently qualified, and some areas have water arsenic exceeding standards or newly discovered villages with arsenic exceeding standards. At the same time, there are still a large number of arsenic poisoning patients in Inner Mongolia Autonomous Region. In the future, the prevention and control of endemic arsenic poisoning in Inner Mongolia Autonomous Region cannot be relaxed, and it is necessary to strengthen water quality monitoring and improve water quality in newly discovered villages with arsenic exceeding standards to prevent the occurrence of new cases.
10.Enhanced heterologous expression of the cytochrome c from uncultured anaerobic methanotrophic archaea.
Lingwei CUI ; Xiaojun FAN ; Yanning ZHENG
Chinese Journal of Biotechnology 2022;38(1):226-237
Cytochrome c is a type of heme proteins that are widely distributed in living organisms. It consists of heme and apocytochrome c, and has potential applications in bioelectronics, biomedicine and pollutant degradation. However, heterologous overexpression of cytochrome c is still challenging. To date, expression of the cytochrome c from uncultured anaerobic methanotrophic archaea has not been reported, and nothing is known about the function of this cytochrome c. A his tagged cytochrome c was successfully expressed in E. coli by introducing a thrombin at the N-terminus of CytC4 and co-expressing CcmABCDEFGH, which is responsible for the maturation of cytochrome c. Shewanella oneidensis, which naturally has enzymes for cytochrome c maturation, was then used as a host to further increase the expression of CytC4. Indeed, a significantly higher expression of CytC4 was achieved in S. oneidensis when compared with in E. coli. The successful heterologous overexpression of CytC4 will facilitate the exploitation of its physiological functions and biotechnological applications.
Anaerobiosis
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Archaea/metabolism*
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Cytochromes c/metabolism*
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Escherichia coli/metabolism*
;
Heme/metabolism*

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