The regulation of rhizosphere bacterial community structure and metabolism by plants in municipal solid waste landfills is a key to enhancing the biodegradation of chlorobenzene (CB). In this study, we employed biodiversity and metabolomics methods to systematically analyze the mechanisms of different plant species in regulating the rhizosphere bacterial community structure and metabolic features and then improved the methane (CH₄) oxidation and CB degradation capacity. The results showed that the rhizosphere soil of Rumex acetosa exhibited the highest CH₄ oxidation and CB degradation capacity of 0.08 g/(kg·h) and 1.72×10^-6 g/(L·h), respectively, followed by the rhizosphere soil of Amaranthus spinosus L., with the rhizosphere soil of Broussonetia papyrifera showing the weakest activity. Rumex acetosa promoted the colonization of Methylocaldum in the rhizosphere, and the small-molecule organic amine, such as triethylamine and N-methyl-aniline, secreted from the roots of this plant enhanced the tricarboxylic acid cycle and nicotinamide metabolism, thereby increasing microbial activity and improving CH₄ and CB degradation efficiency. Conversely, cinnamic acid and its derivatives secreted by Broussonetia papyrifera acted as autotoxins, inhibiting microbial activity and exacerbating the negative effects of salt stress on key microbes such as methanotrophs. This study probed into the mechanisms of typical plants growing in landfill cover soil in regulating bacterial ecological functions, offering theoretical support and practical guidance for the plant-microbe joint control of landfill gas pollution.
Biodegradation, Environmental ; Rhizosphere ; Soil Microbiology ; Waste Disposal Facilities ; Chlorobenzenes/metabolism* ; Bacteria/metabolism* ; Soil Pollutants/metabolism* ; Methane/metabolism* ; Plant Roots/microbiology* ; Amaranthus/microbiology* ; Soil

Landfill is one of the important sources of carbon tetrachloride (CT) pollution, and it is important to understand the degradation mechanism of CT in landfill cover for better control. In this study, a simulated landfill cover system was set up, and the biotransformation mechanism of CT and the associated micro-ecology were investigated. The results showed that three stable functional zones along the depth, i.e., aerobic zone (0-15 cm), anoxic zone (15-45 cm) and anaerobic zone (> 45 cm), were generated because of long-term biological oxidation in landfill cover. There were significant differences in redox condition and microbial community structure in each zone, which provided microbial resources and favorable conditions for CT degradation. The results of biodegradation indicated that dechlorination of CT produced chloroform (CF), dichloromethane (DCM) and Cl^- in anaerobic and anoxic zones. The highest concentration of dechlorination products occurred at 30 cm, which were degraded rapidly in aerobic zone. In addition, CT degradation rate was 13.2-103.6 μg/(m²·d), which decreased with the increase of landfill gas flux. The analysis of diversity sequencing revealed that Mesorhizobium, Thiobacillus and Intrasporangium were potential CT-degraders in aerobic, anaerobic and anoxic zone, respectively. Moreover, six species of dechlorination bacteria and eighteen species of methanotrophs were also responsible for anaerobic transformation of CT and aerobic degradation of CF and DCM, respectively. Interestingly, anaerobic dechlorination and aerobic transformation occurred simultaneously in the anoxic zone in landfill cover. Furthermore, analysis of degradation mechanism suggested that generation of stable anaerobic-anoxic-aerobic zone by regulation was very important for the harmless removal of full halogenated hydrocarbon in vadose zone, and the increase of anoxic zone scale enhanced their removal. These results provide theoretical guidance for the removal of chlorinated pollutants in landfills.
Bacteria/metabolism* ; Biodegradation, Environmental ; Carbon Tetrachloride/metabolism* ; Methane/metabolism* ; Waste Disposal Facilities

Chlorinated hydrocarbons (CAHs) threaten human health and the ecological environment due to their strong carcinogenic, teratogenic, mutagenic and heritable properties. Heterotrophic assimilation degradation can completely and effectively degrade CAHs, without secondary pollution. However, it is crucial to comprehensively understand the heterotrophic assimilation process of CAHs for its application. Therefore, we review here the characteristics and advantages of heterotrophic assimilation degradation of CAHs. Moreover, we systematically summarize current research status of heterotrophic assimilation of CAHs. Furthermore, we analyze bacterial genera and metabolism, key enzymes and characteristic genes involved in the metabolic process. Finally, we indicate existing problems of heterotrophic assimilation research and future research needs.
Bacteria ; metabolism ; Biodegradation, Environmental ; Hydrocarbons, Chlorinated ; metabolism ; Industrial Microbiology ; trends

Chlorinated aliphatic hydrocarbons (CAHs) with characteristics of high toxicity, biological accumulation and recalcitrance to degradation as well as carcinogenicity, teratogenesis and mutagenicity, are seriously harmful to human health and ecological environment. CAHs degradation depends on biotic and abiotic responses that exist diversified interactive effects, so it is important to clarify the mechanism of CAHs degradation via biotic and abiotic mutual promoting to significantly enhance the CAHs-contaminated site restoration. In this work, a series of pathways for CAHs degradation was first introduced and summarized as three means on reductive dechlorination, aerobic cometabolism and direct oxidation, and biotic and abiotic typical factors affecting CAHs degradation were concluded from these. Then, mechanisms of induced degradation and synergistic degradation were indicated from the perspective of mutual promoting degradation both with biotic and abiotic responses, and furthermore, the application and technical limitations of CAHs degradation enhanced via biotic and abiotic mutual promoting were reviewed and analyzed. Finally, the development of CAHs degradation technology in future was prospected.

OBJECTIVETo explore the efficacy of partial resection of puborectalis combined with mutilation of internal anal sphincter(IAS) in the treatment of puborectalis syndrome with high anal pressure.

METHODSTwenty-five cases of puborectalis syndrome with high anal resting pressure in the preoperative examination received the operation of partial resection of puborectalis combined with mutilation of IAS in Zhongnan Hospital of Wuhan University between January 2013 and May 2015. The position of puborectalis was confirmed by touching with the exposure under the transfixion device, and a transverse incision was made by electrotome between 3 and 5 o'clock direction of puborectalis, then partial puborectalis was lifted by vessel clamp at 5 o'clock direction, and about 0.5 cm of muscular tissue was resected. Between 8 to 10 o'clock direction of anal tube, about 1 cm length of transverse incision was made by electrotome, then partial IAS was lifted by vessel clamp and cut off. Preoperative and postoperative 3-month anorectal manometry and defecography were carried out. Wexner constipation score and Cleveland Clinic incontinence score were implemented before surgery and 3, 6, 12 months after operation. This study was registered in the Chinese Clinical Trial Registry (registration number: ChiCTR-ORB-16007695).

RESULTSOf the 25 cases, 18 were male and 7 were female, the average age was 55 years old and the average course of disease was 9 years. Compared with pre-operation, the postoperative 3-month anal resting pressure and maximal squeeze pressure were significantly decreased [(53.56±9.05) mmHg vs. (92.44±7.06) mmHg, (142.80±20.35) mmHg vs. (210.88±20.56) mmHg, respectively, both P=0.000]; anorectal angulation at resting state and forced defecation state increased significantly [(102.32±4.96)degree vs. (95.88±4.01)degree, (117.88±5.95)degree vs. (89.52±3.25)degree, respectively, both P=0.000]. Wexner constipation score of postoperative 3-month, 6-month, 12-month (8.28±3.91, 7.40±3.64 and 8.04±4.74) was significantly lower than the preoperative score (16.00±3.69, all P<0.05), while the score was not significantly different among 3 time points after operation (P>0.05). Cleveland Clinic incontinence score was 0 at postoperative 6 and 12 months, and revealed 20 cases were effective among all the surgical patients(80%).

CONCLUSIONPartial resection of puborectalis combined with mutilation of internal anal sphincter can effectively reduce anal pressure and improve symptoms of outlet obstruction, which is an effective method in the treatment of puborectalis syndrome with high anal pressure.

Anal Canal ; physiopathology ; surgery ; Constipation ; surgery ; Defecation ; Defecography ; Digestive System Surgical Procedures ; methods ; Female ; Gastrointestinal Diseases ; surgery ; Humans ; Male ; Manometry ; Middle Aged ; Muscle Hypertonia ; surgery ; Pelvic Floor ; physiopathology ; surgery ; Pressure ; Treatment Outcome

Objective To evaluate the effect of conversion from mycophenolic acid (MPA) to mizoribine (MZR) in renal transplant recipients with gastrointestinal tract (GI) symptoms.Methods A total of 355 renal transplant recipients with GI symptoms caused by MPA administration were enrolled from April 2015 to March 2017 in 25 different renal transplant centers in China.The symptomatic improvement of GI before (baseline) and after conversion to MZR (1,2,4 weeks) was assessed by each item of GI symptoms indication.In addition,the efficacy and safety of the conversion therapy during 12 months were determined.Results Patients showed improvement in GI symptoms including diarrhea,abdominal pain,abdominal distention and stomachache after conversion to MZR 1,2,4 weeks (P＜0.05).In patients with different severity of diarrhea,conversion to MZR therapy significantly improved diarrhea (P＜0.05).During 12 months,no patient experienced clinical immune rejection.We did not observe any infections,leucopenia and other serious side effects.Conclusion MZR could markedly improve GI symptoms caused by MPA administration in renal transplant recipients.

The clinical data and follow-up information of 4 pediatric patients with pancreatic solid pseudopapillary neoplasm (SPN) admitted in the First Affiliated Hospital of Harbin Medical University between January 2000 and January 2016 were retrospective reviewed.Four patients were all girls aged 8-13 years.All cases were treated with surgical resection and the diagnosis was confirmed histopathologically.Patients were followed up for up to 6 years,and there was no recurrence detected.Pancreatic SPN in children is a potentially malignant borderline tumor.Complete surgical resection is the only option for this disease,and spleen preserving pancreatectomy is the first choice of operation with satisfactory results.

We isolated and enriched mixed microorganisms SWA1 from landfill cover soils supplemented with trichloroethylene (TCE). The microbial mixture could degrade TCE effectively under aerobic conditions. Then, we investigated the effect of copper ion (0 to 15 μmol/L) on TCE biodegradation. Results show that the maximum TCE degradation speed was 29.60 nmol/min with 95.75% degradation when copper ion was at 0.03 μmol/L. In addition, genes encoding key enzymes during biodegradation were analyzed by Real-time quantitative reverse transcription PCR (RT-qPCR). The relative expression abundance of pmoA gene (4.22E-03) and mmoX gene (9.30E-06) was the highest when copper ion was at 0.03 μmol/L. Finally, we also used MiSeq pyrosequencing to investigate the diversity of microbial community. Methylocystaceae that can co-metabolic degrade TCE were the dominant microorganisms; other microorganisms with the function of direct oxidation of TCE were also included in SWA1 and the microbial diversity decreased significantly along with increasing of copper ion concentration. Based on the above results, variation of copper ion concentration affected the composition of SWA1 and degradation mechanism of TCE. The degradation mechanism of TCE included co-metabolism degradation of methanotrophs and oxidation metabolism directly at copper ion of 0.03 μmol/L. When copper ion at 5 μmol/L (biodegradation was 84.75%), the degradation mechanism of TCE included direct-degradation and co-metabolism degradation of methanotrophs and microorganisms containing phenol hydroxylase. Therefore, biodegradation of TCE by microorganisms was a complicated process, the degradation mechanism included co-metabolism degradation of methanotrophs and bio-oxidation of non-methanotrophs.
Biodegradation, Environmental ; Copper ; chemistry ; Methylocystaceae ; metabolism ; Oxidation-Reduction ; Soil Microbiology ; Trichloroethylene ; metabolism

Objective To investigate whether overexpression of VHL can inhibit the growth and metasta-sis of colon cancer .Methods Adenovirus vectors containing VHL were used to overexpress VHL protein in vitro and in vivo.The proliferation,apoptosis and migration of colon cancer cells CT 26 were examined in vitro.The ex-pressions of related proteins were detected by Western blot analysis .Subcutaneous and liver metastasis of colon cancer models were established and the therapeutic effects were evaluated .Results Overexpression of VHL pro-tein inhibited the proliferation and invasion of CT26,and promoted the apoptosis of CT26 via the regulation of COX-2,Bcl-2 and MMP-9.Overexpression of VHL protein inhibited the growth of subcutaneous colon cancer and liver metastasis in vivo .Conclusion Overexpression of VHL protien can inhibit the growth and metastasis of colon cancer ,and enhance the apoptosis of colon cancer ,indicating that VHL can be used as a potential target for colon cancer therapy .

Diabetic nephropathy was one of the diseases with high incidence and difficult to treat in modern society. Modern medicine had focused on the prevention and treatment of this difficult disease to delay its development. ProfessorZhao Zongjiang, who had been working on the treatment of kidney diseases with traditional Chinese medicine (TCM) and modern medicine for many years, had deep understanding on integrative medicine treatment of chronic kidney diseases (CKD), diabetic nephropathy treatment with unique TCM principles, methods, prescriptions and herbs, with rich clinical experiences, rational medication and significant therapeutic effects. Under the guidance of professorZhao Zongjiang, this article started with consumptive kidney disease in combination with a large amount of professorZhao Zongjiang’s research results, for the discussion of professor Zhao Zongjiang’s academic thoughts and clinical experiences in disease treatment to provide references in this field.