LncRNA MRAK052509 competitively adsorbs miR-204-3p to regulate silica dust-induced EMT process.

Silicosis is a systemic disease caused by long-term inhalation of free SiO2 and retention in the lungs. At present, it is still the most important occupational health hazard disease in the world. Existing studies have shown that non-coding RNA can also participate in complex fibrosis regulatory networks. However, its role in regulating silicotic fibrosis is still unclear. In this study, we constructed a NR8383/RLE-6TN co-culture system to simulate the pathogenesis of silicosis in vitro. Design of miR-204-3p mimics and inhibitors to overexpress or downregulate miR-204-3p in RLE-6TN cells. Design of short hairpin RNA (sh-RNA) to downregulate MRAK052509 in RLE-6TN cells. The regulatory mechanism of miR-204-3p and LncRNA MRAK052509 on EMT process was studied by Quantitative real-time PCR, Western blotting, Immunofluorescence and Cell scratch test. The results revealed that miR-204-3p affects the occurrence of silica dust-induced cellular EMT process mainly through regulating TGF-ßRΙ, a key molecule of TGF-ß signaling pathway. In contrast, Lnc MRAK052509 promotes the EMT process in epithelial cells by competitively adsorbing miR-204-3p and reducing its inhibitory effect on the target gene TGF-ßRΙ, which may influence the development of silicosis fibrosis. This study perfects the targeted regulation relationship between LncRNA MRAK052509, miR-204-3p and TGF-ßRΙ, and may provide a new strategy for the study of the pathogenesis and treatment of silicosis.

Prognostic value of extrahepatic metastasis on colon cancer with liver metastasis: a retrospective cohort study.

Introduction: The occurrence of metastasis is a threat to patients with colon cancer (CC), and the liver is the most common metastasis organ. However, the role of the extrahepatic organs in patients with liver metastasis (LM) has not been distinctly demonstrated. Therefore, this research aimed to explore the prognostic value of extrahepatic metastases (EHMs). Methods: In this retrospective study, a total of 13,662 colon patients with LM between 2010 and 2015 were selected from the Surveillance, Epidemiology, and End Results database (SEER). Fine and Gray's analysis and K-M survival analysis were utilized to explore the impacts of the number of sites of EHMs and different sites of EHMs on prognosis. Finally, a prognostic nomogram model based on the number of sites of EHMs was constructed, and a string of validation methods was conducted, including concordance index (C-index), receiver operating characteristic curves (ROC), and decision curve analysis (DCA). Results: Patients without EHMs had better prognoses in cancer-specific survival (CSS) and overall survival (OS) than patients with EHMs (p < 0.001). Varied EHM sites of patients had different characteristics of primary location site, grade, and histology. Cumulative incidence rates for CSS surpassed that for other causes in patients with 0, 1, 2, ≥ 3 EHMs, and the patients with more numbers of sites of EHMs revealed worse prognosis in CSS (p < 0.001). However, patients with different EHM sites had a minor difference in cumulative incidence rates for CSS (p = 0.106). Finally, a nomogram was constructed to predict the survival probability of patients with EHMs, which is based on the number of sites of EHMs and has been proven an excellent predictive ability. Conclusion: The number of sites of EHMs was a significant prognostic factor of CC patients with LM. However, the sites of EHMs showed limited impact on survival. Furthermore, a nomogram based on the number of sites of EHMs was constructed to predict the OS of patients with EHMs accurately.

Homotherapy for heteropathy of Alzheimer's disease and anemia through reducing the expression of toll-like receptor and TNF by steamed Panax notoginseng.

BACKGROUND: One of the effects of Steamed Panax notoginsen (SPN) is to replenish blood, which is mostly used to treat anemia in clinic. SPN has the effect of treating anemia and Alzheimer's disease (AD) in clinical and basic research. In traditional Chinese medicine, anemia and AD have the same characteristics, and their symptoms are qi and blood deficiency. METHODS: First, data analysis was carried out through network pharmacology to predict the action targets of SPN homotherapy in the treatment of AD and anemia. Specifically, TCMSP and relevant literature were used to screen the main active ingredients of Panax notoginseng, and SuperPred was used to predict the action targets of the active ingredients. Disease targets related to AD and anemia were collected through Genecards database, and STRING and protein interaction (PPI) was used for enrichment analysis, Analyze the characteristics of the active ingredient target network on the Cytascape 3.9.0 platform, and use Metascape to enrich the gene ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes Pathway Enrichment (KEGG pathway). Then Drosophila was used as the AD animal model, and the effects of SPN on the climbing ability, olfactory memory and brain Aß, with rats as anemia animal models, the improvement effect of SPN on blood routine and organ index of rats with blood deficiency induced by CTX and APH was analyzed to further explain the therapeutic effect of SPN on these two diseases. Finally, the regulatory effect of SPN on the key active target of allotherapy for AD and anemia was verified by PCR. RESULTS: After the screening, 17 active components and 92 action targets of SPN were obtained. The degree values of components and the first 15 targets are NFKB1, IL10, PIK3CA, PTGS2, SRC, ECFR, CASP3, MTOR, IL1B, ESR1, AKT1, HSP90AA1, IL6, TNF, and Toll-like receptor, it is mainly related to inflammatory response, immune regulation and antioxidation. SPN improved the climbing ability, olfactory memory ability, and Aß42 content in the brain of Aß flies, and significantly reduced the expression of TNF and Toll-like receptor in the brain after treatment. SPN can significantly improve the blood routine index and organ index of anemia rats, and also significantly reduce the expression of TNF and Toll-like receptor in the brain after treatment. CONCLUSION: SPN can regulate the expression of TNF and Toll-like receptor to achieve the same treatment of AD and anemia.

Genome-wide identification, evolution and expression profiles analysis of bHLH gene family in Castanea mollissima.

The basic helix-loop-helix (bHLH) transcription factors (TFs) gene family is an important gene family in plants, and participates in regulation of plant apical meristem growth, metabolic regulation and stress resistance. However, its characteristics and potential functions have not been studied in chestnut (Castanea mollissima), an important nut with high ecological and economic value. In the present study, 94 CmbHLHs were identified in chestnut genome, of which 88 were unevenly distributed on chromosomes, and other six were located on five unanchored scaffolds. Almost all CmbHLH proteins were predicted in the nucleus, and subcellular localization demonstrated the correctness of the above predictions. Based on the phylogenetic analysis, all of the CmbHLH genes were divided into 19 subgroups with distinct features. Abundant cis-acting regulatory elements related to endosperm expression, meristem expression, and responses to gibberellin (GA) and auxin were identified in the upstream sequences of CmbHLH genes. This indicates that these genes may have potential functions in the morphogenesis of chestnut. Comparative genome analysis showed that dispersed duplication was the main driving force for the expansion of the CmbHLH gene family inferred to have evolved through purifying selection. Transcriptome analysis and qRT-PCR experiments showed that the expression patterns of CmbHLHs were different in different chestnut tissues, and revealed some members may have potential functions in chestnut buds, nuts, fertile/abortive ovules development. The results from this study will be helpful to understand the characteristics and potential functions of the bHLH gene family in chestnut.

Effects of etching process and annealing temperature on the ferroelectric properties of atomic layer deposited Al-doped HfO2thin film.

An investigation was conducted with regard to the effect of etching process on the ferroelectric (FE) characteristics of different device structures with Al-doped HfO2thin films; further, the effect of the rapid thermal annealing temperature on the FE properties was elucidated using metal-ferroelectric-metal (MFM) capacitors using TiN electrodes with varying thickness and 4 at.% Al-doped HfO2FE layer. The capacitors were annealed at different temperatures after lithography and etching process; this was aimed at incorporating the FE-orthorhombic phase. The samples annealed after patterning were able to obtain improved FE characteristics due to the amount of tensile stress. The MFM devices that were initially patterned were also studied as a reference. We found that even though it required higher temperature and shorter time to introduce the FE phase, it exhibited more stable as well as promising FE properties and electrical performances with a relatively large remnant polarization (2Pr âˆ¼ 60µC cm-2), a coercive electric field of approximately 2 MV cm-1and high switching current density with less leakage. Our results indicate how the FE properties of the HfO2-based thin films can be engineered through suitable process sequence and post-annealing conditions, thereby verifying the applicable flexibility of FE-HfO2for semiconductor device integration.

Prediction of sediment transport capacity based on slope gradients and flow discharge.

Sediment transport capacity (Tc) is an essential parameter in the establishment of the slope soil erosion model. Slope type is an important crucial factor affecting sediment transport capacity of overland flow, and vegetation can effectively inhibit soil loss. Two new formulae of sediment transport capacity (Tc) are proposed of brown soil slope and vegetation slope in this study and evaluate the influence of slope gradient (S) and flow discharge (Q) on sediment transport capacity of different slope types. Laboratory experiments conducted using four flow discharges (0.35, 0.45, 0.55, and 0.65 L s-1), four slope gradients (3, 6, 9, and 12°), and two kinds of underlying surface (Brown soil slope, Vegetation slope). The soil particle size range is 0.05-0.5mm. The vegetation stems were 2mm in diameter and randomly arranged. The results show that the sediment transport capacity was positively correlated with the flow discharge and slope gradient. The vegetation slope's average sediment transport capacity is 11.80% higher than the brown soil slope that same discharge and slope gradient conditions. The sensitivity of sediment transport capacity to flow discharge on brown soil slope is higher than that of slope gradient. The sensitivity of sediment transport capacity of vegetation slope to slope gradient is more heightened than flow discharge. The sediment transport capacity was well predicted by discharge and slope gradient on brown soil slope (R2 = 0.982) and vegetation slope (R2 = 0.993). This method is helpful to promote the study of the sediment transport process on overland flow.

Energy policy paradox on environmental performance: The moderating role of renewable energy patents.

The environmental and socioeconomic considerations of energy production have become crucial because of the increasingly complex relationship between energy and the environment. This study aims to develop possible mechanisms for perspectives on energy policy and the environment by exploring the mediating role of renewable energy patents. Non-radial data envelopment analysis and panel data models are applied using the panel data from 2010 to 2017 from 30 Chinese provinces. The results show an overall improvement in the environmental performance index (EPI) of China's provinces, but the average EPI is still relatively weak, with an average value between 0.44 and 0.52, which is far below the optimal value 1.. Furthermore, the econometric model offers evidence that provincial renewable energy and emission reduction policies positively impact the enhancement of EPI. The findings have several implications for energy and environmental policies.

Profiling of circular RNAs and circTPCN/miR-634/mTOR regulatory pathway in cervical cancer.

Circular RNAs (circRNAs) are highly stable forms of endogenous non-coding RNA molecules with diverse biological functions. Some of them have been demonstrated to play crucial roles in the initiation or development of cancers through regulation of gene expression. However, the profiles and the roles of circRNAs in tumorigenesis of cervical cancer remain largely unknown. In the current study, we investigated the expression profiles of circRNAs and their potential oncogenic mechanisms in cervical cancer. The expression patterns, obtained using a microarray assay, revealed a total of 192 differentially expressed circRNAs, of which 106 were upregulated and 86 were downregulated, in cervical cancer samples compared with normal cervical samples. The differential expression of circRNAs was validated using quantitative real-time polymerase chain reaction. Two circRNAs (circTPCN and circFAM185A) were confirmed to be significantly upregulated in cervical cancer samples, indicating that they represent potential biomarkers of cervical cancer. The role and the potential molecular mechanism of circTPCN in cervical cancer tumorigenesis were further investigated. Knockdown of circTPCN significantly suppressed proliferation, migration, and invasion and increased apoptosis of cervical cancer cells in vitro. Molecular analysis revealed that circTPCN acted as a sponge of miR-634 to enhance mTOR expression. Thus, the circTPCN/miR-634/mTOR regulatory pathway might be involved in cervical cancer tumorigenesis, and circTPCN is a potential therapeutic target in cervical cancer.

AdipoR2 inhibits human glioblastoma cell growth through the AMPK/mTOR pathway.

BACKGROUND: AdipoR2, which belongs to the seven-transmembrane-domain receptor family, has been shown to play an important role in the development of human tumours, but the underlying mechanisms are poorly understood. In this study, we found that AdipoR2 expression correlates with glioma grade. In addition, we also investigated the mechanisms behind the antiproliferative effects of AdipoR2 in U251 cells (a human glioma cell line) using colony formation and WST-8 growth assays. METHODS: The U251 cell line was cultured in vitro. Western blotting was used to detect the expression of relevant proteins. Quantitative RT-PCR was used to detect AdipoR1 and AdipoR2 expression. Flow cytometry was used to detect cell cycle assay results. The gene expression profiles of glioma samples from the CGGA database were analysed by MATLAB and GSEA software. RESULTS: The AMPK/mTOR pathway plays a central role in the regulation of cell proliferation, differentiation and migration and may promote tumorigenesis. Therefore, we can control cancer progression by modulating the AMPK/mTOR pathway. However, there is no information on the relationship between AdipoR and AMPK/mTOR in central nervous system tumours such as GBM. In this study. We found 648 upregulated genes and 436 downregulated genes correlated with AdipoR2 expression in 158 glioma samples. GSEA suggested that AdipoR2 is a cell cycle-associated gene. The results of the flow cytometry analysis indicated that AdipoR2 induced G0/G1 cell cycle arrest in U251 cells. Furthermore, we identified the AMPK/mTOR signalling axis to be involved in AdipoR2-induced cell cycle arrest. CONCLUSIONS: Our results suggest that AdipoR2 may represent a novel endogenous negative regulator of GBM cell proliferation. These findings also suggest that AdipoR2 may be a promising therapeutic target in GBM patients.

Simultaneous determination of seven effective components in Shenkui Tongmai granules based on UHPLC-MS/MS.

OBJECTIVES: The objective of the study was to establish the quality standard of the formulation of Shenkui Tongmai granules (SKTM) from the perspective of safety and effectiveness. METHODS: A sensitive and specific method to simultaneously detect seven effective components by ultra-high performance liquid chromatography-tandem-mass spectrometry (UHPLC-MS/MS) in SKTM, including calycosin 7-O-ß-d-glucopyranoside, icariin, sodium danshensu, hyperoside, astragaloside IV, hesperidin, and salvianolic acid, was developed and validated. A Kromasil 100-3.5 C18 column with a mobile phase of 6.5 mmol/l ammonium acetate in acetonitrile was used to separate these above-listed components. Gradient programming was used with a flow rate of 0.2 ml/min, and the components were achieved in 13 min. Multiple reaction monitoring (MRM) in positive/negative mode was applied for the MS/MS detection. KEY FINDINGS: The analytical method was satisfactorily validated for linearity, accuracy and precision, repeatability and stability. The developed UHPLC-MS/MS method had high repeatability and accuracy and it was in a good linear relationship within their respective ranges (r = 0.9999) with the RSD value of the sample recovery of less than 5%. CONCLUSIONS: The current method established here is suitable for use in determining seven effective components in SKTM simultaneously, which may provide a new reliable method for overall quality control of SKTM.

[Study on HPLC-characteristic chromatogram for evaluation of quality of Scutellaria Extract and influencing factors of preparations].

This work was carried out to establish and validate the specific characteristic chromatography of Scutellaria Extract and evaluate the quality of commercial Scutellaria Extract and optimize production process parameters. Scutellaria Extract and formulation samples collected from different manufacturers were analyzed using HPLC-characteristic chromatogram. The HPLC characteristic peaks were considered to be the index for the parameters optimization in preparations of Scutellaria Extract. The chemical pattern recognization was applied for the analysis of characteristic peak data. The established characteristic fingerprint method possessed a good precision, repeatability, and stability. Ten common characteristic peaks were determined and identified in the specific chromatogram of 31 batches of Scutellaria Extract and 4 batches of formulation. The process parameters influenced the characteristic peaks area significantly. The similarity analysis results showed that after removing baicalin peak, the similarity of the characteristic chromatography of 9 samples were less than 0.90, indicating that the quality of commercial Scutellaria Extract was inconsistent. Non-parametric test result showed that the relative peaks area of the number 4, 6, 7 characteristic peaks had significant differences(P<0.05), indicating the differences of the Scutellaria Extract quality were mainly reflected in the characteristic peaks 4, 6 and 7(norwogonin-7-O-glucuronide, oroxylin A-7-O-glucuronide, wogonoside, respectively). The cluster analysis accurately classified 31 extract samples and 4 formulation samples into five categories based on 10 characteristic peaks. The quality of Scutellaria Extracts was comprehensively evaluated and ranked by PCA. The result showed that the higher content of baicalin, the score value of quality(F value) was lower, and the quality of the Scutellaria Extract should be evaluated by multi-components instead of a single baicalin component. The optimized characteristic peaks method is stable and reliable. It is advantageous for the extract and formulations integrative quality control by combining the chemical pattern recognization.

Protein acetylation in mitochondria plays critical functions in the pathogenesis of fatty liver disease.

BACKGROUND: Fatty liver is a high incidence of perinatal disease in dairy cows caused by negative energy balance, which seriously threatens the postpartum health and milk production. It has been reported that lysine acetylation plays an important role in substance and energy metabolism. Predictably, most metabolic processes in the liver, as a vital metabolic organ, are subjected to acetylation. Comparative acetylome study were used to quantify the hepatic tissues from the severe fatty liver group and normal group. Combined with bioinformatics analysis, this study provides new insights for the role of acetylation modification in fatty liver disease of dairy cows. RESULTS: We identified 1841 differential acetylation sites on 665 proteins. Among of them, 1072 sites on 393 proteins were quantified. Functional enrichment analysis shows that higher acetylated proteins are significantly enriched in energy metabolic pathways, while lower acetylated proteins are significantly enriched in pathways related to immune response, such as drug metabolism and cancer. Among significantly acetylated proteins, many mitochondrial proteins were identified to be interacting with multiple proteins and involving in lipid metabolism. Furthermore, this study identified potential important proteins, such as HADHA, ACAT1, and EHHADH, which may be important regulatory factors through modification of acetylation in the development of fatty liver disease in dairy cows and possible therapeutic targets for NAFLD in human beings. CONCLUSION: This study provided a comprehensive acetylome profile of fatty liver of dairy cows, and revealed important biological pathways associated with protein acetylation occurred in mitochondria, which were involved in the regulation of the pathogenesis of fatty liver disease. Furthermore, potential important proteins, such as HADHA, ACAT1, EHHADH, were predicted to be essential regulators during the pathogenesis of fatty liver disease. The work would contribute to the understanding the pathogenesis of NAFLD, and inspire in the development of new therapeutic strategies for NAFLD.

Atorvastatin ameliorates depressive behaviors and neuroinflammatory in streptozotocin-induced diabetic mice.

Depression is a chronic and progressive syndrome and commonly associated with several neuropsychiatric comorbidities, of which depression is the most studied. It has been demonstrated that statins also have anti-inflammatory and immunomodulatory properties, which being explored for potential benefits in depression. However, the role of statins in the treatment of diabetes-related depression has not been well examined. Herein, we investigated the effects of atorvastatin on depressive behaviors and neuroinflammation in streptozotocin-induced diabetic mice. Our data indicated that oral administration of atorvastatin at 10 or 20 mg/kg for 3 weeks markedly ameliorated diabetes-associated depressive behaviors reflected by better performance in sucrose preference test (SPT), tail suspension test (TST), and novelty-suppressed feeding test (NSFT). The study further showed that atrovastatin decreased the expression of nucleus NF-κB p65 expression and ameliorated neuroinflammatory responses in prefrontal cortex as evidenced by less Iba-1-positive cells and lower inflammatory mediators including IL-1ß and TNF-α. As expected, atorvastatin-treated diabetic mice exhibited significant improvement of hyperlipidemia rather than hyperglycemia. These results suggest that atorvastatin has the potential to be employed as a therapy for diabetes-related depression.

Mitsugumin 53 promotes mitochondrial autophagy through regulating Ambra1 expression in C2C12 myoblast cells.

In this study, we investigated the function of Mitsugumin 53 (MG53) in regulation of mitochondrial autophagy in skeletal muscle cells and explored its potential application in the prevention and treatment of skeletal muscle atrophy in rats with chronic kidney disease (CKD). The expression of autophagy beclin 1 regulator 1 (Ambra1) and MG53 in skeletal muscles of 5/6 nephrectomized rats was measured, and the effect of MG53 on mitochondrial autophagy of C2C12 myoblasts was investigated by in vitro experiments. Our results show the expression of Ambra1 and MG53 in the skeletal muscle of CKD rats was significantly decreased. In vitro experiments showed that MG53 overexpression could promote the expression of Ambra1 and mitochondrial autophagy in C2C12 cells, suggesting that recovery of autophagy by MG53 intervention may help remove abnormal mitochondria and alleviate muscle atrophy. In conclusion, the damaged or functionally incomplete mitochondria in CKD rats could not be effectively removed, which may be related to the low activity of Ambra1. In vitro experiments showed that MG53 overexpression could promote the expression of Ambra1 in C2C12 cells and restore mitochondrial autophagy. Whether MG53 can help remove abnormal mitochondria and relieve CKD-induced muscle atrophy requires further study.

Synthesis of dodecylamine-functionalized graphene quantum dots and their application as stabilizers in an emulsion polymerization of styrene.

Pickering emulsions have attracted considerable interest due to their potential applications in many fields, such as the food, pharmaceutical, petroleum and cosmetics industries. The study reports the synthesis of dodecylamine-functionalized graphene quantum dots (d-GQDs) and their implementation as stabilizers in an emulsion polymerization of styrene. First, d-GQDs are prepared by thermal pyrolysis of citric acid and dodecylamine in 0.1M ammonium hydroxide. The resulting d-GQDs consist of small graphene sheets with abundant amino, carboxyl, acylamino, hydroxyl and alkyl chains on the edge. The amphiphilic structure gives the d-GQDs high surface activity. The addition of d-GQDs can reduce the surface tension of water to 30.8mNm-1 and the interfacial tension of paraffin oil/water to 0.0182mNm-1. The surface activity is much better than that of previously reported solid particle surfactants for Pickering emulsions and is close to that of sodium dodecylbenzenesulfonate, which is, a classical organic surfactants. Then, d-GQDs are employed as solid particle surfactants for stabilizing styrene-in-water emulsions. The emulsions exhibit excellent stability at pH 7. However, stability is lost when the pH is more than 9 or less than 4. The pH-switchable behaviour can be attributed to the protonation of amino groups in a weak acid medium and dissociation of carboxyl groups in a weak base medium. Finally, 2,2'-azobis(2-methylpropionitrile) is introduced into the Pickering emulsions to trigger emulsion polymerization of styrene. The as-prepared polystyrene spheres display a uniform morphology with a narrow diameter distribution. The fluorescent d-GQDs coated their surfaces. This study presents an approach for the fabrication of amphiphilic GQDs and GQDs-based functional materials, which have a wide range of potential applications in emulsion polymerization, as well as in sensors, catalysts, and energy storage.

Molecular epidemiology of genogroup II noroviruses infection in outpatients with acute gastroenteritis in Nanjing, China (2010-2013).

OBJECTIVE: Human noroviruses (NoVs) of genogroup II are the most common strains detected in sporadic cases of acute nonbacterial gastroenteritis in outpatients in Nanjing. To gain insight into the molecular epidemiology of GII strains, we analyzed 75 positive NoV cases from 2010 to 2013. METHODS: The sporadic cases were detected by real-time PCR with specific primers and probes to human NoVs of genogroup I or II, human sapovirus, human rotavirus, human astrovirus, and human enteric adenovirus. Human NoVs of genogroup II were further studied by VP1 amplification (RT- PCR), cloning, sequencing, and phylogenetic analysis. RESULTS: Rotavirus and human NoVs were more frequently detected in all the cases from 2010 to 2013. Human NoVs infection was more frequent since 2011 and more frequent than rotavirus infection after 2012. Out of the 75 NoV cases of genogroup II, there were 5 GII.6, 11 GII.3, and 59 GII.4. Of the 59 GII.4, 27 cases were previous GII.4.2006b strains that circulated between 2010 and 2012; while 32 cases were the newly emerging GII.4 strains GII.4.2012 from 2011 to 2013. CONCLUSION: Our data confirm other studies on the rapid emergence and displacement of highly virulent GII.4 strains.

Morpheme matching based text tokenization for a scarce resourced language.

Text tokenization is a fundamental pre-processing step for almost all the information processing applications. This task is nontrivial for the scarce resourced languages such as Urdu, as there is inconsistent use of space between words. In this paper a morpheme matching based approach has been proposed for Urdu text tokenization, along with some other algorithms to solve the additional issues of boundary detection of compound words, affixation, reduplication, names and abbreviations. This study resulted into 97.28% precision, 93.71% recall, and 95.46% F1-measure; while tokenizing a corpus of 57000 words by using a morpheme list with 6400 entries.

Comparison and analysis of membrane fouling between flocculent sludge membrane bioreactor and granular sludge membrane bioreactor.

The goal of this study is to investigate the effect of inoculating granules on reducing membrane fouling. In order to evaluate the differences in performance between flocculent sludge and aerobic granular sludge in membrane reactors (MBRs), two reactors were run in parallel and various parameters related to membrane fouling were measured. The results indicated that specific resistance to the fouling layer was five times greater than that of mixed liquor sludge in the granular MBR. The floc sludge more easily formed a compact layer on the membrane surface, and increased membrane resistance. Specifically, the floc sludge had a higher moisture content, extracellular polymeric substances concentration, and negative surface charge. In contrast, aerobic granules could improve structural integrity and strength, which contributed to the preferable permeate performance. Therefore, inoculating aerobic granules in a MBR presents an effective method of reducing the membrane fouling associated with floc sludge the perspective of from the morphological characteristics of microbial aggregates.

In vitro antibacterial activity of chinfloxacin, a new fluoroquinolone antibiotic.

BACKGROUND: Chinfloxacin is a novel synthetic fluoroquinolone with a structure similar to moxifloxacin. The in vitro activity of chinfloxacin was evaluated in the current study. METHOD: Chinfloxacin was tested against a total of 1,739 clinical isolates representing 23 species using the agar dilution method. Studies of bactericidal activity, including minimum bactericidal concentrations (MBC) and time-kill curve determinations, were conducted according to the recommendations of the Clinical and Laboratory Standards Institute. RESULTS: Minimum inhibitory concentrations (MIC)(50)s and MIC(90)s of chinfloxacin were found to be the same or 2-fold lower than those of moxifloxacin against gram-positive isolates except for Streptococcus pyogenes (against which chinfloxacin showed similar MIC(50) as moxifloxacin but 2-fold higher MIC(90)), and the same as or 2-fold higher than those of moxifloxacin against gram-negative isolates. Chinfloxacin showed potent bactericidal activity with MBC/MIC ratios in the range of 1-2 for almost all the isolates tested. Time-kill curves further demonstrated chinfloxacin as a concentration-dependent bactericidal agent usually effective at concentrations of 2 MIC or higher. CONCLUSION: Chinfloxacin showed similar in vitro activity as moxifloxacin.

Dynamic and distribution of ammonia-oxidizing bacteria communities during sludge granulation in an anaerobic-aerobic sequencing batch reactor.

The structure dynamic of ammonia-oxidizing bacteria (AOB) community and the distribution of AOB and nitrite-oxidizing bacteria (NOB) in granular sludge from an anaerobic-aerobic sequencing batch reactor (SBR) were investigated. A combination of process studies, molecular biotechniques and microscale techniques were employed to identify and characterize these organisms. The AOB community structure in granules was substantially different from that of the initial pattern of the inoculants sludge. Along with granules formation, the AOB diversity declined due to the selection pressure imposed by process conditions. Denaturing gradient gel electrophoresis (DGGE) and sequencing results demonstrated that most of Nitrosomonas in the inoculating sludge were remained because of their ability to rapidly adapt to the settling-washing out action. Furthermore, DGGE analysis revealed that larger granules benefit more AOB species surviving in the reactor. In the SBR were various size granules coexisted, granule diameter affected the distribution range of AOB and NOB. Small and medium granules (d<0.6 mm) cannot restrict oxygen mass transfer in all spaces of the sludge. Larger granules (d>0.9 mm) can result in smaller aerobic volume fraction and inhibition of NOB growth. All these observations provide support to future studies on the mechanisms responsible for the AOB in granules systems.