Clinical significance of miR-9-5p in NSCLC and its relationship with smoking.

Purpose: Dysregulated expression of microRNA (miRNAs) in lung cancer has been wildly reported. The clinicopathologic significance of miR-9-5p in non-small-cell lung cancer (NSCLC) patients and its effect on NSCLC progression were explored in this study. Patients and methods: A total of 76 NSCLC patients were included. miR-9-5p expression was evaluated by real-time quantitative polymerase chain reaction (RT-qPCR). Then, in vitro experiments including cell growth curve assays, colony formation assays, and transwell migration assays were performed. Further clinicopathological and prognostic values were explored using bioinformatics analysis of the TCGA database. Results: miR-9-5p expression was significantly increased in tumor tissues (both P < 0.0001). miR-9-5p expression was relatively higher in larger tumors (P = 0.0327) and in lung squamous carcinoma (LUSC) (P = 0. 0143). In addition, miR-9-5p was significantly upregulated in the normal lung tissues of cigarette smokers (P = 0.0099). In vitro, miR-9-5p was correlated with cell proliferation and migration. After that, bioinformatics analysis of the TCGA database indicated that miR-9-5p was correlated with tumor size (P = 0.0022), lymphatic metastasis (P = 0.0141), LUSC (P < 0.0001), and smoking history (P < 0.0001). Finally, a prognostic study indicated high miR-9-5p expression was correlated with poor prognosis in LUAD (P = 0.0121). Conclusion: Upregulation of miR-9-5p may have an oncogenic effect in NSCLC and may be related to smoking. The conclusion of this study may help find new prognostic and therapeutic targets for NSCLC and the exploration of the relationship between smoking and lung cancer.

Building bridges of excellence: a comprehensive competence framework for nurses in hospice and palliative care-a mixed method study.

BACKGROUND: Hospice and Palliative Care (HPC) is in high demand in China; however, the country is facing the shortage of qualified HPC nurses. A well-suited competence framework is needed to promote HPC human resource development. Nevertheless, existing unstandardized single-structured frameworks may not be sufficient to meet this need. This study aimed at constructing a comprehensive multi-structured HPC competence framework for nurses. METHODS: This study employed a mixed-method approach, including a systematic review and qualitative interview for HPC competence profile extraction, a two-round Delphi survey to determine the competences for the framework, and a cross-sectional study for framework structure exploration. The competence profiles were extracted from publications from academic databases and interviews recruiting nurses working in the HPC field. The research team synthesized profiles and transferred them to competences utilizing existing competence dictionaries. These synthesized competences were then subjected to Delphi expert panels to determine the framework elements. The study analyzed theoretical structure of the framework through exploratory factor analysis (EFA) based on a cross-sectional study receiving 491 valid questionnaires. RESULTS: The systematic review involved 30 publications from 10 countries between 1995 and 2021, while 13 nurses from three hospitals were interviewed. In total, 87 and 48 competence profiles were respectively extracted from systematic review and interview and later synthesized into 32 competences. After the Delphi survey, 25 competences were incorporated into the HPC competence framework for nurses. The EFA found a two-factor structure, with factor 1 comprising 18 competences namely Basic Competences; factor 2 concluding 7 competences namely Developmental Competences. CONCLUSIONS: The two-factor HPC competence framework provided valuable insights into the need and directions of Chinese HPC nurses' development.

A feasibility study on home-based kyphosis-specific exercises on reducing thoracic hyperkyphosis in older adults.

Objectives: This study aimed to assess the feasibility of the home-based kyphosis-specific exercises among Chinese older adults with different exercise habits and explore its potential effects on reducing the kyphosis angle and improving physical performance. Methods: A single-group, pre-and post-test design was conducted according to CONSORT 2010 statement: extension for pilot and feasibility trials. A total of 20 participants aged ≥60 with thoracic hyperkyphosis and rehabilitation potential were recruited from four local communities in Wuhan, China. Participants underwent a six-week home-based kyphosis-specific exercises intervention that included warm-up, muscle strengthens, spinal alignment, spinal mobility and flexibility, and cool down five sections (22 exercises). The intervention involved seven 1-h group classes and 35 times daily home practice with identical content. At pre- and post-intervention, the participants' kyphosis angle in two standing postures, static balance, dynamic balance, cardiopulmonary function, dynamic gait assessment, pain, and self-image were assessed and compared. Feasibility was assessed by group class attendance, home practice adherence, and participant evaluations. Results: All participants completed group classes and >75% home practice. Post-intervention, the participant's kyphosis angle in relaxed and best-standing postures was changed by -12.0° (-15.5°, -4.0°) (Z = - 3.98, P < 0.001）and -10.0° (-14.0°, -5.3°) (Z = -3.79, P < 0.001), respectively. In addition, participants had significantly less pain (P < 0.001), better self-image (P < 0.001), and improved performance in five physical assessments (P < 0.01). Different pre-intervention hyperkyphosis angle and daily physical activity did not affect intervention effects. Most participants considered the interventional exercise as moderate intensity and satisfactory. Conclusions: Home-based kyphosis-specific exercises showed the possibility of being a feasible intervention. And it was advantageous to reducing the kyphosis angle and improving physical performance.

Comparative chloroplast genome analysis of Ficus (Moraceae): Insight into adaptive evolution and mutational hotspot regions.

As the largest genus in Moraceae, Ficus is widely distributed across tropical and subtropical regions and exhibits a high degree of adaptability to different environments. At present, however, the phylogenetic relationships of this genus are not well resolved, and chloroplast evolution in Ficus remains poorly understood. Here, we sequenced, assembled, and annotated the chloroplast genomes of 10 species of Ficus, downloaded and assembled 13 additional species based on next-generation sequencing data, and compared them to 46 previously published chloroplast genomes. We found a highly conserved genomic structure across the genus, with plastid genome sizes ranging from 159,929 bp (Ficus langkokensis) to 160,657 bp (Ficus religiosa). Most chloroplasts encoded 113 unique genes, including a set of 78 protein-coding genes, 30 transfer RNA (tRNA) genes, four ribosomal RNA (rRNA) genes, and one pseudogene (infA). The number of simple sequence repeats (SSRs) ranged from 67 (Ficus sagittata) to 89 (Ficus microdictya) and generally increased linearly with plastid size. Among the plastomes, comparative analysis revealed eight intergenic spacers that were hotspot regions for divergence. Additionally, the clpP, rbcL, and ccsA genes showed evidence of positive selection. Phylogenetic analysis indicated that none of the six traditionally recognized subgenera of Ficus were monophyletic. Divergence time analysis based on the complete chloroplast genome sequences showed that Ficus species diverged rapidly during the early to middle Miocene. This research provides basic resources for further evolutionary studies of Ficus.

The Prevalence of Sarcopenia in Chinese Older Adults: Meta-Analysis and Meta-Regression.

Sarcopenia, with risk factors such as poor nutrition and physical inactivity, is becoming prevalent among the older population. The aims of this study were (i) to systematically review the existing data on sarcopenia prevalence in the older Chinese population, (ii) to generate pooled estimates of the sex-specific prevalence among different populations, and (iii) to identify the factors associated with the heterogeneity in the estimates across studies. A search was conducted in seven databases for studies that reported the prevalence of sarcopenia in Chinese older adults, aged 60 years and over, published through April 2020. We then performed a meta-analysis to estimate the pooled prevalence, and investigated the factors associated with the variation in the prevalence across the studies using meta-regression. A total of 58 studies were included in this review. Compared with community-dwelling Chinese older adults (men: 12.9%, 95% CI: 10.7-15.1%; women: 11.2%, 95% CI: 8.9-13.4%), the pooled prevalence of sarcopenia in older adults from hospitals (men: 29.7%, 95% CI:18.4-41.1%; women: 23.0%, 95% CI:17.1-28.8%) and nursing homes (men: 26.3%, 95% CI: 19.1 to 33.4%; women: 33.7%, 95% CI: 27.2 to 40.1%) was higher. The multivariable meta-regression quantified the difference of the prevalence estimates in different populations, muscle mass assessments, and areas. This study yielded pooled estimates of sarcopenia prevalence in Chinese older adults not only from communities, but also from clinical settings and nursing homes. This study added knowledge to the current epidemiology literature about sarcopenia in older Chinese populations, and could provide background information for future preventive strategies, such as nutrition and physical activity interventions, tailored to the growing older population.

Wuhan's experience in curbing the spread of coronavirus disease (COVID-19).

BACKGROUND: Since December 2019, coronavirus disease (COVID-19) has affected over 50 000 people in Wuhan, China. However, the number of daily infection cases, hospitalization rate, lag time from onset to diagnosis date and their associations with measures introduced to slow down the spread of COVID-19 have not been fully explored. METHODS: This study recruited 6872 COVID-19 patients in the Wuchang district, Wuhan. All of the patients had an onset date from 21 December 2019 to 23 February 2020. The overall and weekly hospitalization rate and lag time from onset to diagnosis date were calculated. The number of daily infections was estimated by the back-projection method based on the number of daily onset cases. Their association with major government reactions and measures was analyzed narratively. RESULTS: The overall hospitalization rate was 45.9% (95% CI 44.7 to 47.1%) and the mean lag time from onset to diagnosis was 11.1±7.4 d. The estimated infection curve was constructed for the period from 14 December 2019 to 23 February 2020. Raising public awareness regarding self-protecting and social distancing, as well as the provision of timely testing and inpatient services, were coincident with the decline in the daily number of infections. CONCLUSION: Early public awareness, early identification and early quarantine, supported by appropriate infrastructure, are important elements for containing the spread of COVID-19 in the community.

Construction of the Infection Curve of Local Cases of COVID-19 in Hong Kong using Back-Projection.

This study aimed to estimate the infection curve of local cases of the coronavirus disease (COVID-19) in Hong Kong and identify major events and preventive measures associated with the trajectory of the infection curve in the first two waves. The daily number of onset local cases was used to estimate the daily number of infections based on back-projection. The estimated infection curve was examined to identify the preventive measures or major events associated with its trajectory. Until 30 April 2020, there were 422 confirmed local cases. The infection curve of the local cases in Hong Kong was constructed and used for evaluating the impacts of various policies and events in a narrative manner. Social gatherings and some pre-implementation announcements on inbound traveler policies coincided with peaks on the infection curve.

Exploring the biological stability situation of a full scale water distribution system in south China by three biological stability evaluation methods.

Bacterial regrowth especially opportunistic pathogens regrowth and contamination in drinking water distribution systems (DWDS) have become an emerging threat to public health in the whole world. To explore bacterial regrowth and biological stability, assimilable organic carbon (AOC), biodegradable dissolved organic carbon (BDOC) and bacterial regrowth potential (BRP) were evaluated in a full scale DWDS and bench tests in South China. A significant correlation between BRP and AOC in both water treatment processes (WTP) and DWDS was obtained. For BRP and BDOC, the correlation was more significant in WTP than in DWDS. Both AOC and BRP were significantly correlated with UV254, total organic carbon (TOC), and heterotrophic plate count (HPC) (p < 0.01), whereas BDOC was only significantly associated with UV254, temperature and chlorine residual (p < 0.01). Through a bench test, when chlorine was higher than 0.5 mg/L, the HPC level was low and AOC concentration almost unchanged. On contrary the HPC level increased quickly and declined slightly, with chlorine lower than 0.15 mg/L, which was in accordance with the large amount of biological stability data obtained from DWDS. Through another bench test, the HPC level was positively correlated to AOC concentration and when AOC was below 135 µg/L, the growth rate of HPC was low, which was verified by the analysis of biological stability data from DWDS.

Two-phase anaerobic co-digestion of food waste and sewage sludge.

The feasibility and performance of food waste and sewage sludge co-digestion were investigated to gain insight into their resource utilization. In this study, two-phase anaerobic digestion (TPAD) was operated under a total solids mixing ratio of 1:1 and different sludge retention times (SRTs). Results show that an acidogenic reactor with a 5-day SRT obtained the highest acidification efficiency, and its acetic acid content was dominant. The organic removal rate of a methanogenic reactor (MR) with a 20-day SRT and its corresponding TPAD system with a 25-day SRT were both the highest among the MRs and TPAD systems. Volatile solids and total chemical oxygen demand average removal efficiencies of the TPAD system with a 25-day SRT reached 64.7 and 60.8%, respectively. The MR with a 30-day SRT obtained the minimum ratio of volatile fatty acid to alkalinity (0.12). The methane content generated from the different MRs fluctuated at around 70%. All of the above results can provide reference for future research.

Combined toxicity of pesticide mixtures on green algae and photobacteria.

Different organisms have diverse responses to the same chemicals or mixtures. In this paper, we selected the green algae Chlorella pyrenoidosa (C. pyrenoidosa) and photobacteria Vibrio qinghaiensis sp.-Q67 (V. qinghaiensis) as target organisms and determined the toxicities of six pesticides, including three herbicides (simetryn, bromacil and hexazinone), two fungicides (dodine and metalaxyl) and one insecticide (propoxur), and their mixtures by using the microplate toxicity analysis. The toxicities of three herbicides to C. pyrenoidosa are much higher than those to V. qinghaiensis, and the toxicities of metalaxyl and propoxur to V. qinghaiensis are higher than those to C. pyrenoidosa, while the toxicity of dodine to C. pyrenoidosa is similar to those to V. qinghaiensis. Using the concentration addition as an additive reference model, the binary pesticide mixtures exhibited different toxicity interactions, i.e., displayed antagonism to C. pyrenoidosa but synergism to V. qinghaiensis. However, the toxicities of the multi-component mixtures of more than two components are additive and can be predicted by the concentration addition model.

A novel, selective inhibitor of fibroblast growth factor receptors that shows a potent broad spectrum of antitumor activity in several tumor xenograft models.

The fibroblast growth factor receptors (FGFR) are tyrosine kinases that are present in many types of endothelial and tumor cells and play an important role in tumor cell growth, survival, and migration as well as in maintaining tumor angiogenesis. Overexpression of FGFRs or aberrant regulation of their activities has been implicated in many forms of human malignancies. Therefore, targeting FGFRs represents an attractive strategy for development of cancer treatment options by simultaneously inhibiting tumor cell growth, survival, and migration as well as tumor angiogenesis. Here, we describe a potent, selective, small-molecule FGFR inhibitor, (R)-(E)-2-(4-(2-(5-(1-(3,5-Dichloropyridin-4-yl)ethoxy)-1H-indazol-3yl)vinyl)-1H-pyrazol-1-yl)ethanol, designated as LY2874455. This molecule is active against all 4 FGFRs, with a similar potency in biochemical assays. It exhibits a potent activity against FGF/FGFR-mediated signaling in several cancer cell lines and shows an excellent broad spectrum of antitumor activity in several tumor xenograft models representing the major FGF/FGFR relevant tumor histologies including lung, gastric, and bladder cancers and multiple myeloma, and with a well-defined pharmacokinetic/pharmacodynamic relationship. LY2874455 also exhibits a 6- to 9-fold in vitro and in vivo selectivity on inhibition of FGF- over VEGF-mediated target signaling in mice. Furthermore, LY2874455 did not show VEGF receptor 2-mediated toxicities such as hypertension at efficacious doses. Currently, this molecule is being evaluated for its potential use in the clinic.

A new effect residual ratio (ERR) method for the validation of the concentration addition and independent action models.

BACKGROUND, AIM, AND SCOPE: Glutaraldehyde (GA) often acts as an effective sterilant, disinfectant, and preservative in chemical products. It was found that GA had clearly acute toxicity to aquatic organisms. Furthermore, GA in natural environment could not exist as single species but as complex mixtures. To explore the toxicity interaction between GA and the other environmental pollutant, it is necessary to determine the mixture toxicities of various binary mixtures including GA. Two reference models, concentration addition (CA) and independent action (IA), are often employed to evaluate the mixture toxicity, which can be finished by comparing the concentration-response curves (CRCs) predicted by the reference models with the experimental CRC of the mixture. However, the CRC-based method cannot effectively denote the degree of the deviations from the reference models, especially at very low effect levels. Though the model deviation ratio (MDR) can be used to quantitatively evaluate the deviation of a mixture at EC50 level from the reference model, it is difficult to evaluate the deviations at the lower effect levels. Therefore, the primary aim of this study was to develop a new effect residual ratio (ERR) method to validate the deviations from the reference models at various effect levels. MATERIALS AND METHODS: Four chemicals having possible dissimilar mode of actions with GA, acetonitrile (ACN), dodine (DOD), simetryn (SIM), and metham sodium (MET), were selected as another component in the binary mixtures including GA, which constructed four binary mixtures, GA-ACN, GA-DOD, GA-SIM, and GA-MET ones. For each binary mixture, two equipotent mixture rays where the concentration ratios of GA to another mixture component are respectively EC50 and EC5 ones were designed and their toxicities (expressed as a percent inhibition to Photobacterium phosphoreum) were determined by microplate toxicity analysis. The observed concentration-response curve (CRC) of a ray was compared with that predicted by CA or IA model to qualitatively assess the toxicity interaction of the mixture ray. To quantitatively and effectively examine the deviations at various effect levels from the reference models, a new concept, ERR at an effect, was defined, and the ERR was employed to evaluate the deviation at various effects with confidence intervals. RESULTS: For three binary mixtures, GA-ACN, GA-DOD, and GA-SIM, the CRCs predicted by IA models were almost located in the 95% confidence intervals of the experimental CRCs for both equipotent mixture rays, which indicated the independent actions between binary mixture components. However, two rays of GA-MET binary mixture displayed a little synergistic action because both CRCs predicted by CA and IA were lower than the experimental CRC. ERR showed the same results as MDR, but ERR results at low effect area were clearer than MDR ones. DISCUSSION: In CRC comparison, the deviation of CA (for GA-ACN, GA-DOD, and GA-SIM combinations) or IA (for GA-MET) model from the experimental values could be obviously observed at medium area of the CRC. However, at very low effect levels, both deviations of CA and IA and difference between CA and IA model predictions were not very apparent. Thus, it was difficult to confirm which model, CA or IA, had better predicted power at very low effect levels. MDR in many literatures often refers to a ratio at EC50 level. It was also difficult to reflect not only the deviation fact at the other ECx but also the deviation uncertainty. After we extended the definition of MDR to all ECx and examined the 95% confidence intervals based on observation, the plot of the redefined MDRs at many effect levels could better explain the deviations of CA or IA model from the observation. However, MDRs at very low effect levels did not still reflect the high uncertainty there. The ERRs defined in our paper could explicitly explain the degree of deviation from the reference models and especially reflect the high uncertainty at very low effects. It could be said that the ERR is a better indicator than MDR. CONCLUSIONS: The new ERR validation method developed in our laboratory could provide us with the information about the toxicity interaction between the mixture components and quantitatively assess the accuracy of the reference models (CA or IA) at whole effect levels. The ERR method conquered the invalidation of the classical CRC comparison method on the deviation decision at low effect levels and also got the advantage over the MDR methods. RECOMMENDATIONS AND PERSPECTIVES: It holds promise to become an effective method of hazard and risk assessments of chemical mixtures by well characterizing the uncertainty at very low effect levels.

Formation of shaped barium sulfate-dye hybrids: waste dye utilization for eco-friendly treatment of wastewater.

PURPOSE: Owing to the present complexity and difficulty of concentrated dye wastewater treatment, this work aimed to synthesize a reproducible waste-sorbing material for the treatment of wastewater by forming the dye-conjugating complex hybrid. METHODS: The inorganic/organic hybridization was applied to prepare the objective material by immobilizing waster dye-Mordant blue 9 (MB) with barium sulfate (BaSO4). The composition and pattern of the formed material were determined by spectrometry and characterized by SEM and XRD, and their formation process was clarified. The adsorption of cationic dye-basic blue BO (BB) and copper ion was investigated. RESULTS: The hybrid of MB alone into growing BaSO4 formed the pineapple-like particles while that of the MB/BB-conjugating complex was the rhombus material. The adsorption of BB on the MB-BaSO4 hybrid was probably attributed to ion-pair equilibrium and that of Cu2+ may result from the complexation. The treatment of dye and heavy metal wastewaters indicated that the MB hybrid material removed 99.8% BB and 97% Cu2+ and the dye-conjugating hybrid with growing BaSO4 100% MB, 99.5% BB, and 44% Cu2+. CONCLUSION: The waste MB-BaSO4 hybrid material is efficient to treat cationic dye and Cu2+ wastewater. The dye-conjugating hybridization method is the first to be advanced for in situ wastewater treatment, and it showed a combined effect for the removal of both organic dyes and heavy metals.

[Oxidization characteristic of chlorine on the biofilm in simulated drinking water distribution system].

In the article, the inactivation effect of chlorine on E. coli biofilm and the influence of chlorine oxidization on the contents of assimilable organic carbon (AOC), microbially available phosphorus (MAP) and bacterial regrowth potential (BRP) was investigated in the simulated drinking water distribution system. Results showed that chlorine resulted in more efficient reduction on suspended E. coli than did in biofilm. The inactivation effect of E. coli was influenced by chlorine concentration. Likewise, higher chlorine concentration resulted in more E. coli inactivation rate at the same CT (chlorine concentration multiply by time) value, when biofilm was oxidized by chlorine. Concentrations of AOC and MAP in bulk water increased owing to organic substance dissolved from biofilm. The AOC concentration increased from 20.78 microg/L to 120.17 microg/L, and the MAP was increased from 0.11 microg/L to 0.17 pg/L, and the Chlorine oxidization enhanced BRP concentration in the bulk water. BRP reached maximum at 1.10 x 10(7) CFU/mL when chlorine concentration was 1.0 mg/L, CT value was 100 mg x min/L.

[Mechanism of natural organic matter removal by potassium permanganate composite enhanced coagulation].

Streaming current technique, fluctuation of transmitted light technique, molecular weight distribution and XAD resin adsorption technique were used to study the mechanism of natural organic matter removal by potassium permanganate composite (PPC) enhanced coagulation. Results showed that natural organic matter removal efficiency increased 13% by 0.75 mg/L potassium permanganate composite enhanced coagulation compared with that of alum coagulation alone. Streaming current indicated that potassium permanganate composite decreased the organic matter stability by reducing the surface negative charge, and the SC value increased from 55.2 to 61.4, 69.6 and 87.0 by addition of 0.50, 0.75 and 1.0 mg/L PPC. Coagulation index R indicated both nascent manganese dioxide and subsidiaries played an important role in potassium permanganate composite enhanced coagulation process. Potassium permanganate composite enhanced coagulation increased the removal efficiency of lower molecular weight and hydrophilic organic matter compared with alum coagulation, and hydrophilic organic matter can be reduced from 1.9 mg/L to 1.32 mg/L by the addition of 0.75 mg/L potassium permanganate composite.

Source apportionment of polycyclic aromatic hydrocarbons (PAHs) in surface sediments of the Huangpu River, Shanghai, China.

We applied cluster analysis and principal component analysis (PCA) with multivariate linear regression (MLR) to apportion sources of polycyclic aromatic hydrocarbons (PAHs) in surface sediments of the Huangpu River in Shanghai, China, based on the measured PAH concentrations of 32 samples collected at eight sites in four seasons in 2006. The results indicate that petrogenic and pyrogenic sources are the important sources of PAHs. Further analysis shows that the contributions of coal combustion, traffic-related pollution and spills of oil products (petrogenic) are 40%, 36% and 24% using PCA/MLR, respectively. Pyrogenic sources (coal combustion and traffic related pollution) contribute 76% of anthropogenic PAHs to sediments, which indicates that energy consumption is a predominant factor of PAH pollution in Shanghai. Rainfall, the monsoon and temperature play important roles in the distinct seasonal variation of PAH pollution, such that the contamination level of PAHs in spring is significantly higher than in the other seasons. BRIEF: We apportion PAHs in surface sediments of the Huangpu River and show that coal combustion, traffic-related pollution, and petroleum spillage are the major sources.

Homogeneous modification of cellulose in ionic liquid with succinic anhydride using N-bromosuccinimide as a catalyst.

The homogeneous chemical modification of cellulose with succinic anhydride was investigated in a solvent system containing 1-butyl-3-methylimidazolium chloride ionic liquid and dimethylsulfoxide using N-bromosuccinimide (NBS) as a catalyst. The results showed that the degree of substitution of the succinylated cellulosic samples, in the range of 0.24-2.31, noticeably increased as compared with the products without any catalysts, indicating that NBS was a novel efficient catalyst for cellulose succinoylation in ionic liquids. Fourier transform infrared and solid-state cross-polarization/magic angle spinning (13)C NMR spectroscopies also provided evidence of succinoylation reaction. The results indicated that the reaction of hydroxyl groups at C-6, C-2, and C-3 positions in cellulose occurred. The thermal stability of the succinylated cellulose was found to decrease upon chemical modification.

[Influence of coagulation pretreatment on UF membrane flux].

In this study, the effect of coagulation pretreatment on improvement of UF membrane filtration flux was investigated. The experiment using four water samples having different hydrophobic and hydrophilic compound was focused on the effect of coagulation on removing hydrophobic and hydrophilic fraction of organics and resulting enhanced flux. In the filtration of raw water, the organics removal for the four water samples were in the ranges of 12% and 20%, in which hydrophobic fraction accounting for over 50%, suggesting that membrane prefers to remove hydrophobic fraction. In the addition of 25 mg/L coagulant, the organics removals for the four water samples were in the ranges of 12% and 28%. As coagulant dosage increased to 100 mg/L, removals increased to 25% and 38% accordingly, in which hydrophobic fraction accounting for over 50%, suggesting that coagulation prefers to remove hydrophobic fraction. Coagulation pretreatment could enhance flux of all of water samples studied. The analyses for each organic compound show that after coagulation pretreatment membrane reject hydrophilic fraction mainly due to removal of hydrophobic fraction effectively by coagulation. It can be concluded that the flux decline of UF membrane was mainly caused by hydrophobic compound and hydrophilic compound had less effect on flux.

[Effects of RNA interference of COX-2 gene expression on malignant proliferation of A549 cells in vitro].

OBJECTIVE: To investigate the inhibition of COX-2 gene expression and its effects on malignant proliferation of human lung adenocarcinoma A549 cells after interfering at different target sites in vitro. METHODS: The 3rd, 7th and 10th exon of COX-2 were selected as the targets and three COX-2 siRNA expression vectors with human U6 promoter were constructed. Three siRNA expression vectors and two vacant vectors were transfected into A549 cells expressing COX-2 with lipofectamine, respectively. The transfected cell strains were constructed and the change of COX-2 expression levels was examined by Western blot and RT-PCR. The effects on the proliferation of A549 cells after interfering at different target sites were studied by cell growth curve and colony formation assay in vitro. RESULTS: The three siRNAs and U6 promoter were validated by PCR, restriction endonuclease digestion, DNA sequencing and BLAST alignment, and cloned into the pEGFP vector. The cell strains transfected were named as A549-3, A549-7, A549-10, A549-p and A549-pU6, respectively. A549-p cells showed expression of GFP and A549-3, A549-7, A549-10, A549-p and A549-pU6 cells did not show at 24, 48 and 72 hours after transfection. The results of RT-PCR and Western blot showed an inhibition of COX-2 expression after interfering at three target sites (3rd, 7th and 10th exons). In contrast to A549 cells, the levels of COX-2 mRNA of A549-3, A549-7 and A549-10 cells were reduced by 10.6%, 33.4% and 61.2%, respectively. The levels of COX-2 protein of A549-3, A549-7 and A549-10 cells were reduced by 26.7%, 44.7% and 56.2%, respectively. The results of cell growth curve and colony formation assay showed a slowing down of the growth of A549-10 cells and reduction of their colony formation rate. The other two targets had no apparent effect on the growth of A549 cells. CONCLUSION: There is a significant inhibiting effect of RNA interference on the malignant proliferation of A549 cells in vitro, and the most striking effect can be seen when the 10th exon of COX-2 is taken as the interference target.