MMP-3 gene regulates the carcinogenesis and metabolic process of ovarian cancer, evidence from a Chinese population: Observational study and meta-analysis.

The current investigation aims to explore the relationship between matrix metalloproteinase-3 (MMP-3) gene polymorphism and ovarian cancer (OC) risk. Two hundred forty pathologically confirmed OC patients and 390 healthy controls participated in the present investigation. Polymerase chain reaction-restriction fragment length polymorphism was applied to investigate the present polymorphism. At the same time, the meta-analysis was also performed to comprehensively explore the relationship. Three genotypes (5A/5A, 5A/6A, and 6A/6A) were observed for MMP-3 gene polymorphism. 6A/6A genotype and 6A allele displayed significant increase in OC patients (all P < .05). Meta-analysis found that no significant results (all P > .05). In conclusion, our results indicate that MMP-3 gene polymorphism contributes increased risk to OC for southern Chinese population. And meta-analysis indicates that MMP-3 gene polymorphism contributes no risk to OC in other populations.

CXCL10 May Be Responsible for Susceptibility to Pulmonary Embolism in COVID-19 Patients.

Background: Although the potential of coronavirus disease 2019 (COVID-19) patients to develop pulmonary embolism (PE) is widely recognized, the underlying mechanism has not been completely elucidated. This study aimed to identify genes common to COVID-19 and PE to reveal the underlying pathogenesis of susceptibility to PE in COVID-19 patients. Methods: COVID-19 genes were obtained from the GEO database and the OMIM, CTD, GeneCards, and DisGeNET databases; PE genes were obtained from the OMIM, CTD, GeneCards, and DisGeNET databases. We overlapped the genes of COVID-19 and PE to obtain common genes for additional analysis, including functional enrichment, protein-protein interaction, and immune infiltration analysis. Hub genes were identified using cytoHubba, a plugin of Cytoscape, and validated using the independent datasets GSE167000 and GSE13535. The genes validated by the above datasets were further validated in clinical samples. Results: We obtained 36 genes shared by PE and COVID-19. Functional enrichment and immune infiltration analyses revealed the involvement of cytokines and immune activation. Five genes (CCL2, CXCL10, ALB, EGF, and MKI67) were identified as hub genes common to COVID-19 and PE. CXCL10 was validated in both independent datasets (GSE167000 and GSE13535). Serum levels of CXCL10 in the COVID-19 group and the COVID-19 combined with PE group were significantly higher than those in the healthy control group (P<0.001). In addition, there were significant differences between the COVID-19 group and the COVID-19 combined with PE group (P<0.01). Conclusion: Our study reveals common genes shared by PE and COVID-19 and identifies CXCL10 as a possible cause of susceptibility to PE in COVID-19 patients.

A Chiral Emissive Conjugated Corral for High-Affinity and Highly Enantioselective Recognition in Water.

Accurately distinguishing between enantiomeric molecules is a fundamental challenge in the field of chemistry. However, there is still significant room for improvement in both the enantiomeric selectivity (KR(S) /KS(R) ) and binding strength of most reported macrocyclic chiral receptors to meet the demands of practical application scenarios. Herein, we synthesized a water-soluble conjugated tubular host-namely, corral[4]BINOL-using a chiral 1,1'-bi-2-naphthol (BINOL) derivative as the repeating unit. The conjugated chiral backbone endows corral[4]BINOL with good fluorescent emission (QY=34 % ) and circularly polarized luminescence (|glum | up to 1.4×10-3 ) in water. Notably, corral[4]BINOL exhibits high recognition affinity up to 8.6×1010  M-1 towards achiral guests in water, and manifested excellent enantioselectivity up to 18.7 towards chiral substrates, both of which represent the highest values observed among chiral macrocycles in aqueous solution. The ultrastrong binding strength, outstanding enantioselectivity, and facile accessibility, together with the superior fluorescent and chiroptical properties, endow corral[4]BINOL with great potential for a wide range of applications.

Extracellular RNAs/TLR3 signaling contributes to acute intestinal injury induced by intestinal ischemia reperfusion in mice.

Toll-like receptor 3 (TLR3), one pattern recognition receptor activated by viral and endogenous RNA, has been recently reported to regulate ischemia/reperfusion (I/R) injury in various organs. However, the role of TLR3 in the development of intestinal I/R injury remains unclear. The aim of this study is to evaluate the effects of extracellular RNAs/TLR3 signaling in intestinal I/R injury. An intestinal I/R injury model was established with superior mesenteric artery occlusion both in wild-type and TLR3 knockout (KO, -/-) mice, and MODE-K cells were subjected to hypoxia/reoxygenation (H/R) to mimic the I/R model in vivo. Extracellular RNAs (exRNAs), especially double-stranded RNAs (dsRNAs) co-localized with TLR3, were significantly increased both in vitro and in vivo. Compared with wild-type mice, TLR3 knockout obviously attenuated intestinal I/R injury. Both TLR3/dsRNA complex inhibitor and TLR3 siRNA administration reduced TLR3 expressions and subsequently inhibited intestinal inflammatory cytokine production and apoptosis. In conclusion, exRNAs/TLR3 signaling is a key mechanism that regulates intestinal I/R injury in adult mice, and the TLR3/dsRNA complex inhibitor can be an effective approach for attenuating intestinal I/R-induced inflammatory response and apoptosis.

Gut microbiota-derived succinate aggravates acute lung injury after intestinal ischaemia/reperfusion in mice.

INTRODUCTION: Acute lung injury (ALI) is a major cause of morbidity and mortality after intestinal ischaemia/reperfusion (I/R). The gut microbiota and its metabolic byproducts act as important modulators of the gut-lung axis. This study aimed to define the role of succinate, a key microbiota metabolite, in intestinal I/R-induced ALI progression. METHODS: Gut and lung microbiota of mice subjected to intestinal I/R were analysed using 16S rRNA gene sequencing. Succinate level alterations were measured in germ-free mice or conventional mice treated with antibiotics. Succinate-induced alveolar macrophage polarisation and its effects on alveolar epithelial apoptosis were evaluated in succinate receptor 1 (Sucnr1)-deficient mice and in murine alveolar macrophages transfected with Sucnr1-short interfering RNA. Succinate levels were measured in patients undergoing cardiopulmonary bypass, including intestinal I/R. RESULTS: Succinate accumulated in lungs after intestinal I/R, and this was associated with an imbalance of succinate-producing and succinate-consuming bacteria in the gut, but not the lungs. Succinate accumulation was absent in germ-free mice and was reversed by gut microbiota depletion with antibiotics, indicating that the gut microbiota is a source of lung succinate. Moreover, succinate promoted alveolar macrophage polarisation, alveolar epithelial apoptosis and lung injury during intestinal I/R. Conversely, knockdown of Sucnr1 or blockage of SUCNR1 in vitro and in vivo reversed the effects of succinate by modulating the phosphoinositide 3-kinase-AKT/hypoxia-inducible factor-1α pathway. Plasma succinate levels significantly correlated with intestinal I/R-related lung injury after cardiopulmonary bypass. CONCLUSION: Gut microbiota-derived succinate exacerbates intestinal I/R-induced ALI through SUCNR1-dependent alveolar macrophage polarisation, identifying succinate as a novel target for gut-derived ALI in critically ill patients.

Gut microbiota-derived indole 3-propionic acid partially activates aryl hydrocarbon receptor to promote macrophage phagocytosis and attenuate septic injury.

Sepsis is associated with a high risk of death, and the crosstalk between gut microbiota and sepsis is gradually revealed. Indole 3-propionic acid (IPA) is a gut microbiota-derived metabolite that exerts immune regulation and organ protective effects. However, the role of IPA in sepsis is not clear. In this study, the role of IPA in sepsis-related survival, clinical scores, bacterial burden, and organ injury was assessed in a murine model of cecal ligation and puncture-induced polymicrobial sepsis. Aryl hydrocarbon receptor (AhR) highly specific inhibitor (CH223191) was used to observe the role of AhR in the protection of IPA against sepsis. The effects of IPA on bacterial phagocytosis by macrophages were investigated in vivo and vitro. The levels of IPA in feces were measured and analyzed in human sepsis patients and patient controls. First, we found that gut microbiota-derived IPA was associated with the survival of septic mice. Then, in animal model, IPA administration protected against sepsis-related mortality and alleviated sepsis-induced bacterial burden and organ injury, which was blunted by AhR inhibitor. Next, in vivo and vitro, IPA enhanced the macrophage phagocytosis through AhR. Depletion of macrophages reversed the protective effects of IPA on sepsis. Finally, on the day of ICU admission (day 0), septic patients had significantly lower IPA level in feces than patient controls. Also, septic patients with bacteremia had significantly lower IPA levels in feces compared with those with non-bacteremia. Furthermore, in septic patients, reduced IPA was associated with worse clinical outcomes, and IPA in feces had similar prediction ability of 28-day mortality with SOFA score, and increased the predictive ability of SOFA score. These findings indicate that gut microbiota-derived IPA can protect against sepsis through host control of infection by promoting macrophages phagocytosis and suggest that IPA may be a new strategy for sepsis treatment.

Gut Microbial Metabolite Pravastatin Attenuates Intestinal Ischemia/Reperfusion Injury Through Promoting IL-13 Release From Type II Innate Lymphoid Cells via IL-33/ST2 Signaling.

Intestinal ischemia/reperfusion (I/R) injury is a grave condition with high morbidity and mortality. We previously confirmed that intestinal I/R induces intestinal flora disorders and changes in metabolites, but the role of different metabolites in intestinal I/R injury is currently unclear. Based on targeted metabolic sequencing, pravastatin (PA) was determined to be a metabolite of the gut microbiota. Further, intestinal I/R model mice were established through superior mesenteric artery obstruction. In addition, a co-culture model of small intestinal organoids and type II innate lymphoid cells (ILC2s) was subjected to hypoxia/reoxygenation (H/R) to simulate an intestinal I/R model. Moreover, correlation analysis between the PA level in preoperative feces of patients undergoing cardiopulmonary bypass and the indices of postoperative intestinal I/R injury was carried out. IL-33-deficient mice, ILC2-deleted mice, and anti-IL-13 neutralizing antibodies were also used to explore the potential mechanism through which PA attenuates intestinal I/R injury. We demonstrated that PA levels in the preoperative stool of patients undergoing cardiopulmonary bypass were negatively correlated with the indices of postoperative intestinal I/R injury. Furthermore, PA alleviated intestinal I/R injury and improved the survival of mice. We further showed that PA promotes IL-13 release from ILC2s by activating IL-33/ST2 signaling to attenuate intestinal I/R injury. In addition, IL-13 promoted the self-renewal of intestinal stem cells by activating Notch1 and Wnt signals. Overall, results indicated that the gut microbial metabolite PA can attenuate intestinal I/R injury by promoting the release of IL-13 from ILC2s via IL-33/ST2 signaling, revealing a novel mechanism of and therapeutic strategy for intestinal I/R injury.

Ethnicity-stratified analysis of the association between P53 rs1042522 polymorphism and women HPV infection: A meta-analysis.

BACKGROUND: Human papillomavirus (HPV) infection, especially persistent high risk HPV infection stands as the leading reason for cervical cancer morbidity. P53 protein can activate multiple tumor suppressor genes, leading to cervical cancer progression. In recent years, the relationship between P53 gene rs1042522 polymorphism and HPV infection has been investigated. However, their conclusions were contradictory and ambiguous. OBJECTIVES: The present meta-analysis is to estimate whether P53 rs1042522 polymorphism confers risk to HPV infection in cervical specimens. METHODS: Relevant literatures were searched by searching databases including Pubmed, Embase, the Cochrane library, China National Knowledge Infrastructure (CNKI). Search time is from database foundation to January 2021. RESULTS: Eight literatures were enrolled in the present meta-analysis. Positive finding between HPV infection of cervical specimens and P53 rs1042522 polymorphism was found in Brazilian population by allele contrast (Pro versus. Arg: OR = 0.52, 95%CI = 0.35-0.79), homozygote comparison (Pro/Pro versus. Arg/Arg: OR = 0.43, 95%CI = 0.20-0.94), and dominate genetic model (Pro/Pro + Arg/Pro versus. Arg/Arg: OR = 0.29, 95%CI = 0.09-0.93). The similar phenomenon was also found in Arabian population. CONCLUSION: We conclude that P53 rs1042522 polymorphism contributed a decreased risk to HPV infection in Brazilian and Arabian population.

[Rapid chemome profiling of chemical components of Lonicerae Japonicae Flos using DI-MS/MS~(ALL)].

A new method of MS/MS~(ALL) was designed to sequentially record a MS~2 spectrum at each unit mass window through gas phase fractionation concept, so as to offer an opportunity for universal MS~2 spectral recording with direct infusion(DI). As a proof-of-concept, DI-MS/MS~(ALL) was applied for rapid chemome profiling of a famous herbal medicine named Lonicerae Japonicae Flos. After each MS~2 spectrum was correlated to its precursor ion, the structural annotation was conducted by applying well-defined mass cracking rules, matching the mass spectral data with literatures and referring to those accessible databases. As a result, a total of 54 components were identified from Lonicerae Japonicae Flos extract, including 21 phenolic acids, 13 flavonoids, 12 iridoids, 4 triterpenoids and 4 other compounds. Therefore, DI-MS/MS~(ALL) is a powerful tool for comprehensive, rapid qualitative analysis of chemical profiles of traditional Chinese medicine and other chemical components of complex systems.

High-fat diet-induced obesity affects alpha 7 nicotine acetylcholine receptor expressions in mouse lung myeloid cells.

Ample evidence indicates that obesity causes dysfunctions in the lung. Previous studies also show that cholinergic anti-inflammatory pathways play crucial roles in obesity-induced chronic inflammation via α7 nicotinic acetylcholine receptor (α7nAChR) signaling. However, it remains unclear whether and how obesity affects the expressions of α7nAChR in myeloid cells in the lung. To address this question, we treated regular chow diet-fed mice or high-fat diet induced obese mice with lipopolysaccharide (LPS) or vehicle via endotracheal injections. By using a multicolor flow cytometry approach to analyze and characterize differential cell subpopulations and α7nAChR expressions, we find no detectable α7nAChR in granulocytes, monocytes and alveolar macrophages, and low expression levels of α7nAChR were detected in interstitial macrophages. Interestingly, we find that a challenge with LPS treatment significantly increased expression levels of α7nAChR in monocytes, alveolar and interstitial macrophages. Meanwhile, we observed that the expression levels of α7nAChR in alveolar and interstitial macrophages in high-fat diet induced obese mice were lower than regular chow diet-fed mice challenged by the LPS. Together, our findings indicate that obesity alters the expressions of α7nAChR in differential lung myeloid cells.

Physic perspective fusion of electromagnetic acoustic transducer and pulsed eddy current testing in non-destructive testing system.

Comprehensive non-destructive testing (NDT) for pipelines is a critical and challenging task. This paper proposes a novel physic perspective fusion NDT method of electromagnetic acoustic transducer (EMAT) and pulsed Eddy current testing (PECT) for detecting hybrid defects. This transceiver-integrated fusion sensor structure can simultaneously excite ultrasound and pulsed eddy current. Therefore, the generated ultrasound is applied to detect deep defects, while the eddy current detects surface defects. The theoretical derivation of EMAT and PECT fusion mechanism has been developed for analysis and interpretation of the results. In addition, numerical simulation on the detection of hybrid defects including surface defects with different width, depth and multiple bottom-thinning defects has been conducted. Experiments on both ferromagnetic and non-ferromagnetic material verify the feasibility of composite detection. Finally, tests have been validated on pipeline with weld defects, and the results show that the composite inspection method is capable of monitoring thickness variations and inspecting surface defects. This article is part of the theme issue 'Advanced electromagnetic non-destructive evaluation and smart monitoring'.

[Construction and Application of Early Warning System for Soil Environmental Quality].

Early warning of soil environmental quality is an important basis for implementing classified and graded soil risk management measures. To quickly understand the regional soil environmental quality and take effective measures in time to prevent continuous soil pollution before deterioration of soil environmental quality, a simple, effective, and quantifiable early warning system for soil environmental quality of agricultural land and development land was respectively established based on environmental capacity and pollutant input-output flux theory. Furthermore, corresponding method and mechanism for early warning were defined based on soil environmental quality standards, food safety standards, and carcinogenic risk coefficients. The agricultural land in Youxian county and the development area within the fifth-ring in Beijing were chosen to assess the soil environmental quality and predict risks of heavy metals exceeding standards in different scenarios. The results show that the soil environmental quality of the agricultural land in Wangling and Taoshui Town both can be classified to the fifth early warning level. Compared with other remediation measures, the Cd contents of soil can be lowered to risk screening levels in the short term by the scenario of "paddy straw not returned to the field". The soil quality in the development area within the fifth-ring in Beijing belongs to the first early warning level under both the "no intervention" and the "decreased input" scenarios, which means that Cd, Cu, Pb, and Zn all need more than 50 years to reach their threshold values to pose potential health risks.

[Construction and Application of an Evaluation System for Soil Environmental Carrying Capacity].

To understand the effect of soil environmental carrying capacity on pollutants and human activities, as well as to effectively prevent the aggravation of soil pollution and control soil environmental risks, a comprehensive indicator system for soil environmental carrying capacity is developed by analyzing the input-output flux and risk characteristics of soil pollutants. Furthermore, an evaluation method for soil environmental carrying capacity is proposed by defining safety coefficients related to evaluation indicators. Based on evaluation of soil environmental quality, the system reflects soil properties, pollution evolution trends, and risk characteristics, focusing on the soil buffering function. Further, a quantitative evaluation is carried out to assess the regional soil environmental carrying capacity of heavy metals on development land in Beijing. The results show that the soil environmental carrying capacity of Cu, Zn, Pb, and Cd in Beijing varies widely. The soil environmental carrying capacity of Cd is much lower than that of other elements. Four policy recommendations are proposed as significant for effective soil pollution prevention and control:clarifying concepts for soil environmental carrying capacity, improving the evaluation framework, constructing an information database, and implementing demonstration pilots.

Whole genome sequencing analysis of a dexamethasone-degrading Burkholderia strain CQ001.

This study is to analyze the functional genes and metabolic pathways of dexamethasone degradation in Burkholderia through genome sequencing.A new Burkholderia sp. CQQ001 (B. CQ001) with dexamethasone degrading activity was isolated from the hospital wastewater and sequenced using Illumina Hiseq4000 combined with the third-generation sequencing technology. The genomes were assembled, annotated, and genomically mapped. Compared with six Burkholderia strains with typical features and four Burkholderia strains with special metabolic ability, the functional genes and metabolic pathways of dexamethasone degradation were analyzed and confirmed by RT-qPCR.Genome of B. CQ001 was 7,660,596 bp long with 6 ring chromosomes. The genes related to material metabolism accounted for 80.15%. These metabolism related genes could participate in 117 metabolic pathways and cover various microbial metabolic pathways in different environments and decomposition pathways of secondary metabolites, especially the degradation of aromatic compounds. The steroidal metabolic pathway containing 1 ABC transporter and 9 key metabolic enzymes related genes were scattered in the genome. Among them, the ABC transporter, KshA, and KshB increased significantly under the culture conditions of dexamethasone sodium phosphate as carbon source.B. CQ001 is a bacterium with strong metabolic function and rich metabolic pathways. It has the potential to degrade aromatics and other exogenous chemicals and contains genes for steroid metabolism. Our study enriches the genetic information of Burkholderia and provides information for the application of Burkholderia in bioremediation and steroid medicine production.

[Ecohydrologic separation of the mixing process between precipitation and soil water: A review.] / é™æ°´ä¸ŽåœŸå£¤æ°´æ··åˆè¿‡ç¨‹çš„ç”Ÿæ€æ°´æ–‡åˆ†ç¦»çŽ°è±¡åŠå ¶ç ”ç©¶è¿›å±•.

Within the framework of traditional translatory flow, infiltrating precipitation and water at any soil depth is firstly well mixed and eventually enters the stream. Based on the dual stable isotope approach (δD and δ18O), recent studies showed that ecohydrologic separation occurs during the mixing process between precipitation and soil water. Namely, soil water has two pools: soil bound water which includes unavailable and available water used by plants, and soil mobile water entering the stream. The partial mixing of both water pools is defined as hydrologic connectivity. In this review, the concept and meaning of ecohydrologic separation are explained systematically. We described the mixing process between precipitation and soil water, and water isotopes (δD and δ18O) of soil bound water and mobile water in detail. We summarized the advantages and disadvantages of the direct and substitute methods to measure δD and δ18O in soil water, bound water, and mobile water. We reviewed the researches on hydrologic separation and connectivity of soil bound water and mobile water in runoff plot and watershed, including the qualitative research based on the direct and substitute methods, and the quantitative research using the models and control experiments. At last, we proposed that further studies should strengthen the research on the qualitative and quantitative methods of ecohydrological separation, and their influences on traditional ecohydrology models.

Circulating microRNAs as biomarkers for Sepsis secondary to pneumonia diagnosed via Sepsis 3.0.

BACKGROUND: Sepsis biomarkers have limited specificity and sensitivity. Few studies have investigated microRNA (miRNA) biomarkers for sepsis secondary to pneumonia. This study aims to investigate the diagnostic and prognostic values of miRNAs in sepsis secondary to pneumonia. METHODS: Sepsis 3.0 was used to diagnose sepsis. Screening was performed through the Agilent miRNA chip technology by using the following criteria: p < 0.05, fold ≥2 or < 0.5, or copy number > 50 change. This study recruited 52 patients with pneumonia, including 31 males (59.6%) and 21 females (40.4%), 44 patients with sepsis secondary to pneumonia were diagnosed via Sepsis 3.0 (34 [77.3%] males and 10 [22.7%] females), and 21 healthy controls were used for miRNA verification. The miRNA levels were detected through fluorescence real-time quantitative polymerase chain reaction (qRT-PCR). RESULTS: Fluorescence qRT-PCR detection showed that the miR-7110-5p and miR-223-3p expression levels in both patient groups were upregulated compared with those in the healthy controls. The expression levels differed between patients with pneumonia and those with sepsis secondary to pneumonia. The sensitivity and specificity of miR-7110-5p to differentiate sepsis from healthy controls were 84.2 and 90.5%, whereas those of miR-223-3p were 82.9 and 100%, respectively. Multivariate analysis of variance suggested that the presence of sepsis affected the miR-223-3p level (p = 0.041), whereas the presence of sepsis (p = 0.000) and the underlying disease (p = 0.025) influenced the miR-7110-5p level. CONCLUSIONS: MiR-223-3p could be utilized to predict sepsis secondary to pneumonia.

[Study on Immunophenotypes and Gene of Acute Lymphoblastic Leukemia--Review].

Transplantation-associated thrombotic microangiopathy (TA-TMA) is one of the fatal complications of hematopoietic stem cell transplantation(HSCT). The pathogenesis of TA-TMA has not been fully elucidated. The latest researches show that the abnormal activation of the complement system may lead to widespread endothelial injury which may play an important role in the pathogenesis of this disease. Incontrotable hypertension, proteinuria, increase of soluble C5b-9 concentration and early pericardial effusion are the risk factors of TA-TMA . In this review, the latest advances of pathogenesis, early diagnosis, treatment and other aspects of the progress of TA-TMA are summarized, so as to provide new ideas to early diagnosis and treatment in TA-TMA.

Prognostic significance of osteopontin in acute myeloid leukemia: A meta-analysis.

Osteopontin (OPN) has been investigated in the field of tumor research for several years. However, the prognostic role of OPN overexpression in acute myeloid leukemia (AML) remains controversial. A meta-analysis of four studies, including a total of 492 patients, was performed to determine the association of OPN with overall survival (OS) in AML patients. The random-effects model of Der Simonian and Laird was used to synthesize data; hazard ratio (HR) with its 95% confidence interval (CI) was used as the effect size estimate. It was observed that serum-based OPN was inversely correlated with OS and the difference was statistically significant (HR=1.83; 95% CI: 1.43-2.35; P<0.001). Experimental findings indicate that OPN overexpression is associated with a poor prognosis in AML and may be of prognostic value for AML stage and metastasis.

[Effect of dexamethasone contamination in drinking water on intestinal flora in mice].

OBJECTIVE: To evaluate the effect of water pollution with dexamethasone on intestinal flora in mice. METHODS: Twenty Balb/c mice were randomly divided into control group and low-, moderate- and high-dose dexamethasone groups. The mice in dexamethasone groups were exposed to dexamethasone sodium phosphate in drinking water at doses of 0.035, 0.225, and 2.25 ng for 36 days. The changes in behaviors, fur condition, and feces of the mice were observed daily. All the mice were sacrificed at 36 days and the tissues in the ileocecal region was collected for denaturant gradient gel electrophoresis (DGGE) of 16S rDNA V6 variable regions of microbes and sequence analysis with BLAST. RESULTS: The mice in the 3 dexamethasone groups all showed aggressive behaviors. Cluster analysis of DGGE graph showed relatively stable floras in the ileocecal region in all the mice, but principal component analysis identified differences in the dominating flora among the groups. Diversity analysis of the flora revealed significantly increased amount and types of bacteria in the intestinal flora in all the 3 dexamethasone groups (P<0.05 or 0.01) compared with the control group. Sequence analysis of 16S rDNA V6 regions showed 15 common bacterial species and 2 differential species between the dexamethasone groups and the control group with changes in the type and proportion of the dominating bacterium in the dexamethasone groups. Lactobacillus colonization was detected in the control group but not in moderate- and high-dose dexamethasone groups, and Shigella species were found in the latter two groups. CONCLUSIONS: Water contamination with dexamethasone can affect the nervous system of mice, cause changes in the types and amounts of intestinal bacteria and the dominating bacteria, and inhibit the colonization of probiotics in the intestinal floras to increase the risk of invasion by intestinal pathogenic bacteria.

[Impact of Precipitation on Fenghe River Water and Aquatic Microorganisms].

In view of that the Fenghe River water pollution has become more and more serious, nitrogen and organic matter pollution were put forward as the important study targets. Community structure of the microorganisms could reflect the water pollution condition to a certain degree. By investigating the correlation between the water condition changes and the microbial community variation, it make possible to look upon river pollution from different perspectives. By the use of Illumina high-throughout sequencing, we found that the dominant genera were Acinetobacter, Comamonadaceae, Pseudomonas and Escherichia in Fenghe River aquatic environment. Flavobacterium and Enterobacteriaceae which are known as bacteria closely related to human activities, were found to account for larger percentages in the wet season than in the dry season, thus showing that the river was more influenced by anthropogenic activities in the wet season. The water quality was better in the wet season, while the microbial community structure was more stable and the diversity condition was better in the dry season. From the aspect of chemical pollution and microbe, this research helps to carry out planning for protection of drinking water sources and improvement of water environmental condition.