Impact of water quality on the microbial diversity in the surface water along the Three Gorge Reservoir (TGR), China.

The Three Gorges Reservoir (TGR), one of the world's largest reservoirs, has crucial roles in flood control, power generation, and navigation. The TGR is contaminated because of the human activities, and how the contaminated water influences the distribution of the microbial community have not been well studied. In this study, we collected 41 freshwater samples from 13 main dwelling districts along the TGR to investigate the water quality, the distribution of the microbial community, and how water quality affects the microbial community structure. The sampling sites cover the whole TGR along the stream, with 670 km distance. Our results show that both water quality and the compositions of bacterial community vary along the TGR. The distribution of bacterial community is closely related to the local water quality. There is the highest concentration of chemical oxygen demand (COD), the highest relative abundance of Firmicutes, and the highest relative abundance of Bacillus in the upstream, compared to the middle and down streams. Redundancy analysis (RDA) showed that PO43- and COD were the main environmental factors influencing on the structure of bacterial community. The relative abundance of nitrification and denitrification functional genes also altered along the streams. These findings provide the basic data for water quality, the distribution of bacterial community, the link of environmental factors, and the bacterial community structure along the TGR, which guides the local environmental protection agency to launch protection strategy for maintaining the ecosystem health of the TGR.

New Alkaloid and Aromatic Glucoside from the Flowers of Cymbidium Lunagrad Eternal Green.

In this paper, we investigated the chemical components of the flowers of Cymbidium Lunagrad Eternal Green for the first time. In the whole post-fertilization, a new alkaloid, named Lunagrad A (1), and a new aromatic glucoside, named Lunagrad B (2), were isolated from the MeOH extract of the flowers of Cymbidium Lunagrad Eternal Green, along with other six known aromatic compounds (3-8) and three flavone glucosides (9-11). These structures were determined on the basis of NMR experiments, as well as chemical evidence.

[Limonoids from seeds of Azadirachta indica and their cytotoxic activity].

Eight limonoids were isolated from 95% ethanol extracts of neem(Azadirachta indica) seeds by various chromatographic methods. By comparison of their spectroscopic data with those reported in the literatures, these limonoids were determined as salannin(1), 1-detigloyl-1-isobutylsalannin(2), salannol-3-acetate(3), salannol(4), spirosendan(5), 1-detigloyloxy-3-deacetylsalannin-1-en-3-one(6), nimbin(7) and 6-deacetylnimbin(8). Compounds 2 and 5 were firstly isolated from this genus and 5 represented the only example of its type. And 6 is a new natural product. 6 showed inhibitory activity against HeLa and HL-60 cells, with IC50 of(21.61±4.37) and(27.33±5.74) µmol·L⁻¹, respectively. Both 7 and 8 mildly inhibited the growth of HeLa cells, with IC50 of (33.15±5.24) and (38.56±6.41) µmol·L⁻¹, respectively.

[Chemical constituents from Pteris dispar and their anti-tumor activity in vitro].

The dried whole plant of Pteris dispar were milled and extracted with 95% EtOH. The resulting dried extract was isolated by kinds of chromatographic column, including polyamide, Sephadex LH-20, preparative HPLC. As a result, ten diterpenes were isolated from the plant. By analyzing of ESI-MS and NMR spectroscopic data, the structures were established as geopyxin B(1), geopyxin E(2), ent-11α-hydroxy-18-acetoxykaur-16-ene(3), ent-14ß-hydroxy-18-acetoxykaur-16-ene(4), neolaxiflorin L(5), ent-3ß,19-dihydroxy-kaur-16-ene(6), ent-3ß-hydroxy-kaur-16-ene(7), 7ß,17-dihydroxy-16α-ent-kauran-19-oic acid 19-O-ß-D-glucopyranoside ester(8), crotonkinin C(9)and crotonkinin C(10). Compounds 1-10 were obtained from P. dispar for the first time. Compounds 1 and 2 showed moderate activities against Bel-7402 with IC50 values of 7.50 and 10.60 µmol•L⁻¹, and against HepG2 with IC50 values of 6.68,11.80 µmol•L⁻¹, respectively.

[Bioactive lignans from Silybum marianum].

The seeds of Silybum marianum were extracted by hot water, and the extract was isolated by D101 macroporous resin, MCI resin, MPLC, HPLC, et al. As a result, 7 compounds including tricin 4'-O-[threo-ß-guaiacyl-(7″-O-methyl)-glyceryl] ether(1), tricin 4'-O-[erythro-ß-guaiacyl-(7″-O-methyl)-glyceryl] ether(2), 5'-methoxyhydnocarpin-D(3),palstatin(4),(8R,7'S,8'R)-5,5'-dimethoxy-7-oxolariciresinol 9'-O-D-xylopyranoside(5), 9-O-D-glucopyranoside(6), and(-)-haplomyrtoside(7) were isolated and identified for the first time. Compounds 1, 3, 4, and 5 exhibited activity against influenza A(H5N1)with IC50 value of 0.65, 0.21, 0.32, and 0.56 µmol•L⁻¹, respectively. Compounds 1, 2, 6, and 7 exhibited cytotoxity against HepG-2 with IC50 value of 0.35, 0.25, 0.53, 0.66 µmol•L⁻¹, respectively.

[Chemical constituents from Pteris multifida and cytotoxic activity].

The materials were extracted by 95% ethanol, and the extracting solution was isolated by kinds of chromatographic columns including polyamide, MCI, preparative MPLC, and preparative HPLC. Eight diterpenes and two sesquiterpenes were isolated from the plant. On analysis of ESI-MS and NMR spectroscopic data, the structures were established as ent-3ß-hydroxy-kaur-16-en-19-al (1), 4-epi-kaurenic acid (2), mitrekaurenone (3), 7ß,16α,17-trihydroxy-ent-kauran-19-oic acid (4), crotonkinin E (5), crotonkinin F (6), pterisolic acid A (7), pterisolic acid C (8), (2R)-pterosin P (9), and dehydropterosin B (10). Compounds 1-6 were obtained from Pteris for the first time, and compounds 7-10 were obtained from P. ensiformis for the first time. Compounds 5-8 showed moderate activity against HCT-116, HepG2 and BGC-823 cell lines, separately.

[Bioactive quinolizidine alkaloids from Sophora tonkinensis].

Twelve quinolizidine alkaloids were isolated from Sophora tonkinensis by means of silica gel, preparative MPLC, and preparative HPLC. On analysis of NMR spectroscopic data, their structures were established as 3-(4-hydroxyphenyl)-4-(3-methoxy-4-hydroxyphenyl)-3,4-dehydroquinolizidine(1), lanatine A(2), cermizines C(3), senepodines G(4), senepodines H(5), jussiaeiines A(6), jussiaeiines B(7),(+)-5α-hydroxyoxysophocarpine(8),(-)-12ß-hydroxyoxysophocarpine(9),(-)-clathrotropine(10),(-)-cytisine(11), and (-)-N-methylcytisine(12), respectively. Compounds 1-7 were first isolated from Sophora L. plant. In the in vitro assays,the isolated compounds 1, 3, 6-10 exhibited potent activity against CVB3 with IC50 of 6.40, 3.25, 4.66, 3.21, 0.12, 0.23 and 1.60, and with selective index values(SI=TC50/IC50)of 12.0, 5.6, 13.0, 15.1, 50.1, 26.2, and 23.6, respectively. Compounds 1, 3, and 7 exhibited activity against staphylococcus aureus(ATCC 29213)with MICvalues of 8.0, 3.5, 6.0 g•L⁻¹, respectively. Compounds 1, 3, 7, and 12 exhibited activity against staphylococcus aureus(ATCC 33591)with MIC values of 18.0, 7.5, 8.0, 12.0 g•L⁻¹, respectively. Compounds 2, 6, 7 exhibited activity against Escherichia coli(ATCC 25922) with MIC values of 1.0, 3.2, 0.8 g•L⁻¹.

Isolation and purification of two antioxidant peptides from alcalase hydrolysate of Arca subcrenata.

OBJECTIVE: To investigate the constituents with antioxidant activities from alcalase hydrolysate of Arca subcrenata. METHODS: The consecutive chromatographic methods were employed,including ion-exchange chromatography, gel filtration chromatography, and reverse phase high-performance liquid chromatography (RP-HPLC). The amino acid sequences of the purified antioxidant peptides were determined by automated Edman degradation. RESULTS: Under the guidance of the assay of scavenging free radicals, two peptides with antioxidant activities, termed as A-Bg1 and A-Bh, were isolated and purified from the alcalase hydrolysate of Arca subcrenata. CONCLUSION: Constituents from the hydrolysate of Arca subcrenata might be a new potential resource of antioxidants.

The ß-catenin-LINC00183-miR-371b-5p-Smad2/LEF1 axis promotes adult T-cell lymphoblastic lymphoma progression and chemoresistance.

BACKGROUND: High-intensity chemotherapy regimens are often used in adult T-cell lymphoblastic lymphoma (T-LBL) patients. Nevertheless, the response rate remains unsatisfactory due to emergence of chemoresistance. Growing evidence has shown that long non-coding RNAs (lncRNAs) are involved in tumor progression and chemoresistance. Herein, we investigated the potential role of lncRNAs in T-LBLs. METHODS: RNAseq was used to screen and identify candidate lncRNAs associated with T-LBL progression and chemoresistance. Luciferase reporter assay was used to examine the binding of miR-371b-5p to the 3'UTR of Smad2 and LEF1, and the binding of TCF-4/LEF1 to the promoter of LINC00183. Chromatin immunoprecipitation assay was undertaken to analyze the connection between LEF1 and the LINC00183 promoter region. RNA immunoprecipitation assays were used to explore the mechanism whereby LINC00183 regulated miR-371b-5p. MTT and flow cytometry assays were used to measure apoptosis of T-LBL cells. RESULTS: LINC00183 was upregulated in T-LBL progression and chemoresistant tissues in both the Sun Yat-sen University Cancer Center dataset and the First Affiliated Hospital of Anhui Medical University dataset. High expression of LINC00183 was correlated with poorer overall survival and progression-free survival of T-LBL patients compared to those with low expression of LINC00183. Furthermore, miR-371b-5p was negatively regulated by LINC00183. In vivo and in vitro assays showed that LINC00183-mediated T-LBL chemoresistance depended on miR-371b-5p expression. The direct binding of miR-371b-5p to Smad2 and LEF1 was verified by luciferase assays. It was shown that TCF4/LEF1 could bind to the LINC00183 promoter site and increase its transcript level. Downregulation of miR-371b-5p led to increased expression of Smad2/LEF1, and in turn increased LINC00183 expression. Additionally, phospho-Smad2 promotes nuclear translocation of ß-catenin, LINC00183 downregulation decreased chemoresistance induced by ß-catenin and TGF-ß1 in T-LBL cells. CONCLUSION: We unraveled a ß-catenin-LINC00183-miR-371b-5p-Smad2/LEF1 feedback loop that promotes T-LBL progression and chemoresistance, indicating that LINC00183 may serve as a potential therapeutic target in T-LBLs.

[Normative research on bacteriostasis and relieving itching external therapeutic function of kochiae fructus].

OBJECTIVE: To normalize bacteriostasis and relieving itching external therapeutic function of Kochiae Fructus. METHODS: Itching guinea pig model caused by histamine, itching mice model, eczema guinea pig model caused by OVA, and inhibitory effect on pathogens in vitro were used to observe the itching threshold, symptoms and other related physiological index, as well as the inhibitory effect on the normal skin fungi by water extraction of Kochiae Fructus to evaluate the external therapeutic function of Kochiae Fructus. RESULTS: The itching threshold of guinea pig itching model treated by water extraction of Kochiae Fructus at high, medium and low three dosage level, could be significantly increased when compared with negative control group (P < 0.05 or P < 0.01); Red speckle of OVA guinea pig model treated by water extraction of Kochiae Fructus at high, medium and low three dosage level, could be significantly decreased when compared with negative control group (P < 0.05 or P < 0.01); The number of itching and total time of itching within 30 minutes of mice model caused by R-glycose anhydride treated by water extraction of Kochiae Fructus at high, medium and low three dosage level, could be significantly decreased when compared with negative control group (P < 0.05 or P < 0.01); Several common skin fungi could be significantly inhibited by the water extraction of Kochiae Fructus. MIC of the water extraction of Kochiae Fructus on Trichophyton mentagrophytes, Trichophyton rubrum, Microsporum canis, Trichophyton violaceum, and Trichophyton schoenleini were 3.12%, 0.78%, 0.78%, 0.78%, 0.78%, respectively. CONCLUSION: Kochiae fructus has the effect of bacteriostasis and relieving itching.

Role of manganese superoxide dismutase (Mn-SOD) against Cr(III)-induced toxicity in bacteria.

The toxicity of Cr(VI) was widely investigated, but the defense mechanism against Cr(III) in bacteria are seldom reported. Here, we found that Cr(III) inhibited bacterial growth and induced reactive oxygen species (ROS). After exposure to Cr(III), loss of sodA not only led to the excessive generation of ROS, but also enhanced the level of lipid peroxidation and reduced the GSH level, indicating that the deficiency of Mn-SOD decreased the bacterial resistance ability against Cr(III). The adverse effects of oxidative stress caused by Cr(III) could be recovered by the rescue of Mn-SOD in the sodA-deficient strain. Besides the oxidative stress, Cr(III) could cause the bacterial morphology variation, which was distinct between the wild-type and the sodA-deficient strains due to the differential expressions of Z-ring division genes. Moreover, Mn-SOD might prevent Cr(III) from oxidation on the bacterial surface by combining with Cr(III). Taken together, our results indicated that the Mn-SOD played a vital role in regulating the stress resistance, expression of cell division-related genes, bacterial morphology, and chemistry valence state of Cr. Our findings firstly provided a more in-depth understanding of Cr(III) toxicity and bacterial defense mechanism against Cr(III).

The ß-catenin/TCF-4-LINC01278-miR-1258-Smad2/3 axis promotes hepatocellular carcinoma metastasis.

Hepatocellular carcinoma (HCC) metastasis is largely responsible for HCC-associated recurrence and mortality. We aimed to identify metastasis-related long non-coding RNAs (lncRNAs) to understand the molecular mechanism of HCC metastasis. We first identified that miR-1258 was downregulated in HCC tissues both in The Cancer Genome Atlas (TCGA) and Sun Yat-sen University Cancer Center (SYSUCC) dataset. MiR-1258 expression negatively correlated with recurrence-free survival and overall survival of HCC patients. MiR-1258 overexpression inhibited migration and invasion of HCC cells both in vitro and in vivo, whereas miR-1258 downregulation promoted cell metastasis. Luciferase assays verified direct binding of miR-1258 to Smad2 and Smad3, thereby attenuating TGF-ß/Smad signaling. We further established that lncRNA LINC01278 was a negative regulator of miR-1258. In vivo and in vitro assays demonstrated that LINC01278-mediated HCC metastasis was dependent on miR-1258 expression. Furthermore, miR-1258 downregulation in turn increased LINC01278 expression. We also observed that TCF-4 could bind to the LINC01278 promoter site. In addition, LINC01278 downregulation decreased migration and invasion of HCC cells induced by ß-catenin and TGF-ß1 both in vitro and in vivo. We uncovered a novel mechanism for ß-catenin/TCF-4-LINC01278-miR-1258-Smad2/3 feedback loop activation in HCC metastasis, and the study indicated that LINC01278 could serve as a therapeutic target for HCC metastasis.

Structural characterization and immunoregulatory activity of a new polysaccharide from Citrus medica L. var. sarcodactylis.

A new homogeneous heteropolysaccharide (CMSPA90-1) was purified from bergamot by DEAE sepharose fast flow and Sephadex G-75 columns, and was shown to have a molecular weight of 17.6 kDa. Its chemical structure was elucidated by acid hydrolysis and methylation analysis, along with high-performance anion-exchange chromatography, Fourier transform infrared spectroscopy coupled with gas chromatography-mass spectrometry, NMR spectroscopies, the Congo red test, and circular dichroism. CMSPA90-1 consisted of a pyranoside and funanside with branches containing α- and ß-configurations simultaneously. Arabinose and glucose might form an arabinoglucan backbone. The ultrastructure of CMSPA90-1 was further characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The results of thermogravimetric analysis (TGA) revealed that CMSPA90-1 had good thermal stability. The results of DPPH˙ and ABTS+˙ radical scavenging assays indicated that CMSPA90-1 exhibited free-radical-scavenging properties. Otherwise, CMSPA90-1 could promote the proliferation of mouse splenocytes and the neutral red phagocytosis of RAW264.7 cells, which indicated that CMSPA90-1 could be researched and developed as one of the potential functional foods or natural medicines.

Fingerprint analysis of anti-tumor active polypeptides from Arca subcrenata by HPLC.

RP-HPLC was applied to analyze active polypeptides in Arca subcrenata, and the optimal condition for separation was also set up: temperature: 30 degrees C; wavelength: 280 nm; flow rate: 1.0 ml/min; Solvent A consisted of 80% acetonitrile and 0.1% trifluoroacetic acid (TFA) and solvent B contained 0.1% TFA. In this condition, ten samples' fingerprints were gained, in one of which the genuine fraction exhibited fourteen "common peaks" representing the characteristics of the constituents.

[Study on HPEC fingerprint of cultured Cordyceps militaris].

OBJECTIVE: To investigate the High Performance Capillary Electrophoresis (HPCE) fingerprint of cultured Cordyceps militaris (L.) Link. METHODS: Separation was performed on a 50 cm x 75 microm uncoated capillary with 0.5 mmol/L borate solution (pH 9. 18) as HPEC buffer. The run voltage was 20 Kv, temperature 25 degrees C and the DAD detection was set at 254nm. RESULTS: Fingerprint consisted of 11 common peaks. The validation of methods was satisfied with the requirements for SFDA's technical regulations. CONCLUSION: The method was accurate and simple and suitable to the quality control of cultured Cordyceps militaris (L.) Link.

[Review on investigations related to chemical constituents and biological activities of Periplaneta americana].

With the fast development of medicinal animals as new drugs, research on Periplaneta americana become hot recently. Several drugs which mainly consisted of P. americana were approved for clinical applications. The chemical constituents and pharmacological bioactivities of this insect were summarized herein, which provides informativon for further researches on this medicinal animal.

[Nitrification and Denitrification Rates in a Small Tributary, Nanhe River, of Three Gorge Dam Reservoir During Water Collection and Release Events].

Three Gorge Dam Reservoir (TGDR) is a new forming ecosystem and its sediments dynamics remains unknown. Investigation on the nitrification and denitrification dynamics of sediments of TGDR during water collection and release events-anti-seasonal actions-is critical for nitrogen management in TGDR. In this study, we sampled sediments in three locations (upstream, center, and downstream along water flow) of South River, located in a typical small tributary, Nanhe, in TGDR during 2015 water collection and release events to characterize its physiochemical property and determine its nitrification and denitrification rates using acetylene inhabitation method. The results showed that the concentrations of physiochemical parameters of sediments (total carbon, total nitrogen, nitrate, and ammonia) were significantly higher (P<0.05) in water collection event than those in water release event, suggesting there were external materials (e. g., soil) entering into TGDR. Furthermore, the nitrification rate of sediments in water collection event[194.06 µmol·(m2·h)-1] was significantly higher than that in water release event[16.52 µmol·(m2·h)-1]. Sediments nitrification rate was positively correlated to the physiochemical parameters. In contract, the denitrification rate of sediments was higher in water release event[647.20 µmol·(m2·h)-1] than that in water collection event[24.04 µmol·(m2·h)-1). Accordingly, the denitrification rate of sediments was negatively correlated to the physiochemical parameters.

Investigation of microbial community structure of a shallow lake after one season copper sulfate algaecide treatment.

In present work we described, for the first time, the phylogenic structure of the microbial community in a shallow freshwater lake (Hawk Island Lake, located in the Lower Peninsula of the State of Michigan, U.S.A.) after one season (four times during May to August 2007) of CuSO4 treatment for algae growth control. The microbial community structure was characterized by terminal restriction fragment length polymorphism (TRFLP), clone library and 454 pyrosequencing. The similar structure of water chemistry measured across three sampling sites suggested that the lake was well mixed. The concentration of chlorophyll a (chl-a) and turbidity was low, 3.35 ± 1.62 µg/L and 2.5 ± 1.9 NTU, respectively, implying that photosynthesis was suppressed. TRFLP profiles showed that the lake was dominated by 16 terminal fragments (TFs), accounting for 85.5-92.6% abundance. Analysis of similarity (ANOSIM) showed that the difference in microbial community structure between upper and lower depths of the water column was not significant (P=0.101). These results suggested that the microbial community structure within the lake was similar. Clone library and 454 pyrosequencing indicated that the lake was dominated by freshwater phyla, Proteobacteria, Bacteroides, and Actinobacteria. Moreover, the large number of unclassified bacteria (27.4% of total 2090,454 sequences) suggested a complex microbial community structure in the lake.

[Investigation of Antibiotic Resistance Genes (ARGs) in Landfill].

Antibiotic resistant genes (ARGs), an emerging contaminant, have been detected worldwide in various environments such as sediments and river. However, little is known about ARGs distribution in landfill. In this study, we investigated five ARGs [sulfonamides resistant genes (sulI and sulII), chloramphenicols resistant gene (cat), ß-lactams resistant gene (bla-SHV), and tetracyclines resistant gene (tetW)] in refuse samples collected from jiangeungou landfill (Xi'an, China) by real-time PCR. We then correlated the ARGs and physiochemical properties of refuse to examine the link between them. Results showed that all tested ARGs have been detected in all samples, suggesting that landfill served as ARGs reservoir. The highest copies numbers of sulII, sulI, tetW, bla-SHV, and cat were (3.70 ± 0.06) x 10(8) copies · g(-1) ( dry refuse), (9.33 · 0.06) x 10(6) copies · g(-1) (dry refuse), (2.27 0.08) x 10(5) copies · g(-1) (dry refuse), (3.68 ± 0.09) x 10(4) copies · g(-1) (dry refuse), and (1.39 ± 0.10) x 10(4) copies · g(-1) (dry refuse), respectively. Further, sulI, sulII, and cat positively correlated to moisture and sulI and cat negatively correlated to pH.

Production and characterization of high efficiency bioflocculant isolated from Klebsiella sp. ZZ-3.

In this study, a new bioflocculant (ZZ-3) is isolated and evaluated. This novel flocculant was derived Klebsiella, which was identified by 16S rDNA sequencing as well as biochemical and physiological analyses. The composition of ZZ-3 was found to be 84.6% polysaccharides and 6.1% protein. More specifically, the amount (moles) of the polysaccharides rhamnose, mannose, and galactose were found to be 6.48, 2.47, and 1.74 greater than glucose, respectively. Results show ZZ-3 has a relatively high molecular weight (603-1820 kDa) and contains many functional groups (hydroxyl, amide, carboxyl, and methoxyl) that likely contribute to flocculation. The results of microscopic observation, zeta potential measurements, and ZZ-3 bioflocculant structure suggested that bridging was the main mechanism for flocculation with kaolin. Based on a high flocculation efficiency, thermal stability, pH tolerance and the ability to flocculate without additional cations, ZZ-3 shows potential for industrial application.