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Shiga toxin-producing Escherichia coli (STEC) is known as a kind of foodborne pathogens that can produce Shiga toxin type1, type 2, or both, encoded by stx1 and stx2 genes, respectively. Rapid and accurate detection of STEC and stx1/stx2 subtyping assay in food and environment is essential for foodborne outbreak investigation. In this study, a method for the accurate and rapid subtyping of STEC single colony using asymmetric polymerase chain reaction (asPCR) combined with lateral flow immunoassay (LFIA) was established. AsPCR was conducted using biotinylated stx1 and digoxin-labeled stx2 primers to obtain several single stranded DNA amplicons labeled with biotin or/and digoxin. Subsequently, these amplicons were tagged with specific probes labeled with carboxylate-modified red polystyrene microspheres using sequential hybridization. Finally, STEC with different Shiga toxin gene types could be distinguished depending on the appearance of different test lines on an LFIA strip. Thus, the STEC single colony could be identified and subtyped accurately and conveniently using this method. This method showed high specificity. Twenty-four strains of STEC in milk were detected and subtyped using our method, which combines asPCR with LFIA.

A dummy molecularly imprinted polymers (DMIP) for phenol was synthesized by a thermal polymerization method with acrylamide as the functional monomer, ethylene dimethacrylate as the crosslinker, 2,2-azobisisobutyronitrile as the free-radical initiator, acetonitrile as the porogenic solvent, and sulfadiazine, a phenol analogue, as the template. In comparison to other adsorbents, the synthesized DMIP showed a higher capacity and rate of adsorption. The adsorption amount of the DMIP adsorbents for phenol reached 6.09 ± 0.15 mg/g, and the adsorption rate of the DMIP was about 0.406 ± 0.01 mg g−1·min−1. The results indicate that the Freundlich model fit the adsorption model of DMIP for phenol. The adsorption model of DMIP for phenol was multilayer adsorption. This showed that the DMIP synthesized by bulk polymerization could be used as a novel adsorbent for the removal of phenol from contaminated water. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

A method for the quantitative monitoring of sulfadiazine (SD) residues in pork was established by molecular imprinted column coupling with high performance liquid chromatography (HPLC). The molecular imprinted column was selected as an extraction device. To obtain the optimum extraction efficiency, several parameters related to the molecular imprinted column, including column solvent, flow-rate, eluent of the sample matrix and eluent volume, were investigated. The sample solution was directly injected into the device for the extraction after simple extraction. Under the optimum conditions, the relative standard deviations (RSD) was ≤ 6.1%, and the recoveries for SD were higher than 75.6%. In comparison with the AL-SPE column, the MIP-SPE column had good reusability and extraction efficiency. This method was successfully applied to the determination of sulfadiazine residues in pork.

Taking into account the process and mechanism of lifting pressure were complex due to the condensation and shock wave, a one-dimensional theory model based on direct contact condensation is presented to analyze the lifting pressure character of steam-water two phase flow injector, and some key issues, such as inter-phase mass transfer computed by the average condensation heat transfer coefficient and phase volume fraction determined by steam plume, are discussed in detail. The regulations of discharge mass flow and output temperature are decoupling control according to the theory model, and the inlet water mass flow is to determine the output temperature, the variable throat section of steam nozzle is to determine the discharge mass flow.

Drought stress is one of the major constraints to rice ( Oryza sativa L.) production and yield stability especially in rainfed ecosystems and is getting worse as the climate changes worldwide. Dongxiang wild rice (DXWR) Oryza rufipogon Griff., contains drought resistant gene. Improving drought resistance of cultivars is crucial to increase and stabilize rice grain yield via transferring resistant gene from species related to rice. In this paper, four upland rice, sixty backcross inbred lines (BILs) derived from BC 1 F 5 of R974//DXWR/R974, and their parents were employed to evaluate drought-resistance at seedling stage in the greenhouse. Nine traits were recorded for assessment of drought resistance, including maximum root length (MRL), number of roots (NR), shoot length (SL), dry root weight (DRW), fresh root weight (FRW), root relative water content (RRWC), leaf relative water content (LRWC), level for rolling leaf (LRL), and seedling survivability under repeat drought (SSRD). Using more than 88% of accumulative contribution resulted from the principal component analysis (PCA), the nine traits were classified into five independent principal components and the line 1949 showed the highest resistance. Analysis on the stepwise regression equation and correlation demonstrated that MRL, RN, FRW, and RRWC significantly influenced the drought resistance, thus could be used as comprehensive index for drought resistance at the seedling stage. Using the major gene plus polygene mixed inheritance model of quantitative traits, the inheritance of drought-resistance of BIL population at seedling stage was mostly controlled by two independent genes plus polygene. As a result, the DXWR could be precious resources for genetic improvement of drought resistance in cultivated rice.

Monoclonal antibody 7G5 (McAb 7G5), which recognises the zearalenone (ZEN), was used to select for peptides that mimic the ZEN by employing a library of filamentous phages that have 7-mer peptides on their surfaces. After three rounds of panning, two mimotope peptides were obtained to be able to mimic ZEN in binding with the McAb 7G5, their amino acid sequences were DAVILLM and HHCHWWH. Enzyme-linked immunosorbent assay (ELISA) for detect ZEN was established with the phages. In the most sensitive assay, the linear range of the inhibition curve was 100–10,000 pg/ml, the detection limit was 100 pg/ml. The results demonstrated that those phage peptides could be used as the surrogate of ZEN to establish the immunoassay.

Blood samples were collected from patients with leukemia (n = 150) or lymphoma (n = 150) in the Cancer Hospital from March to September 2014. The specific antibodies (IgG, IgM) to, and circulating antigens (CAg) of Toxoplasma gondii were determined by ELISA. A 529 bp specific sequence was amplified by PCR from the genomic DNA of T. gondii. T. gondii-specific IgG positive rate in patients with leukemia and lymphoma were 16.0% (24/150) and 20.0% (30/150), respectively, which were significantly higher than that of healthy persons (6.4%, 7/110) (P0.05). IgM positive rate of the leukemia patients, lymphoma patients, and healthy persons was 2.7% (4/150), 1.3% (2/150), and 0.9% (1/110) (P0.05), respectively. No significant difference was found in IgM and CAg positive rate among leukemia patients, lymphoma patients, and healthy persons (P0.05). No specific band (529 bp) was detected in all samples.

Micromonospora carbonacea JXNU-1 is an actinomycete with broad-spectrum antimicrobial activity, isolated from soil samples from the farmland in the area of Yaohu Lake in Nanchang, China. Here, we report the whole-genome sequence of M. carbonacea JXNU-1.

This study is to investigate the effect of rhein lysinate on inducing human breast cancer cell line SK-Br-3 apoptosis and the role of HER-2 signal pathway in the apoptosis. MTT assay was used to detect SK-Br-3 cell proliferation. Cell cycle and apoptosis were analyzed by flow cytometry. The protein expression and the protein phosphorylation of HER-2 signal pathway were detected by Western blotting. The level of HER-2 mRNA was detected by RT-PCR and the level of HER-2 expression was also detected by immunofluorescence cytochemical methods. The results showed that rhein lysinate remarkably inhibited breast cancer SK-Br-3 cell proliferation. The IC50 value for 48 h treatment was 85 micromol x L(-1). Apoptosis in SK-Br-3 cells was induced by rhein lysinate in a dose dependent manner. The protein expressions of HER-2, NF-KB, and the protein phosphorylation of HER-2 were downregulated, however the protein expression of p53 and p21 was upregulated after rhein lysinate treatment. The level of HER-2 mRNA decreased by using RT-PCR assay and the level of HER-2 expression was also decreased by using immunofluorescence cytochemical assay after rhein lysinate treatment. It can be concluded that rhein lysinate could inhibit SK-Br-3 cell proliferation and induce apoptosis. HER-2/NF-kappaB/p53/p21 signal pathway might be involved in this process. Rhein lysinate has a good prospect to be an adjuvant chemotherapeutic drug.

Heat shock factor 1 (HSF1) is the key protein in regulating stress response. It can be activated under heat, oxidative or another stress conditions. Dominant-positive and dominant-negative HSF1 are two types of HSF1 mutants. Both of them gain the DNA binding activity in the absence of stress. In addition, dominant-positive HSF1 acquires transcriptional activity, which dominant-negative HSF1 does not acquire. In this paper, the progress of using these HSF1 mutants in the research of cancer, neurodegenerative disorders and cardiovascular diseases will be discussed.

To investigate the chemosensitivity to lidamycin (C-1027) in mdr1 gene overexpressing cancer cell lines established by drug induction and by gene-transfection.DNA was cloned by RT-PCR and then eukaryotic expressing recombinant plasmid pcDNA3. 1/mdrl was constructed. Using Lipofectamine 2000, a strain of stably transfected human hepatoma cancer cells, HepG2/mdrl, was obtained. The mdr1 mRNA level, P-glycoprotein (P-gp) level and the activity of P-gp to extrude drugs in cancer cells were determined by RT-PCR, immunofluorescence analysis and rhodamine 123 efflux assay. The chemosensitivity of cancer cells with low or high mdr1 expression to lidamycin and other antitumor drugs was tested by MTT assay.The mdr1 mRNA and P-gp levels in KBv200, MCF-7/ADR, and stably transfected HepG2/mdr1 cells were much higher than that in respective parent KB, MCF-7 and HepG2 cells. The IC50 values of lidamycin for KBv200, MCF-7/ADR and HepG2/mdrl cells were (0.24 +/- 0.20) nmol x L(-1), (0.028 +/- 0.011) nmol x L(-1), and (0.020 +/- 0.011) nmol x L(-1), respectively. Compared with parental cells, the values of resistant fold for KBv200, MCF-7/ADR and HepG2/mdr1 cells to lidamycin were 6.8, 1.6 and 1.3 fold; to adriamycin were 37.2, 181.3 and 8.8 fold; to taxol were 336.8, 49.2 and 40.3 fold, respectively.Lidamycin is highly active to multidrug resistant cancer cells. The chemosensitivity of those resistant cancer cells to lidamycin is approximately at the similar level as that of parent cancer cells.

To investigate the effect of doxycycline, an antimicrobial antibiotic inhibiting type IV collagenase, on the development of pulmonary fibrosis induced by bleomycin (BLM) in mice.Gelatin zymography assay was used to detect the secretion of 72,000 and 92,000 type IV collagenase in HT-1080 cells and the activity of these enzymes in vitro. Experimental pulmonary fibrosis was induced by intra-tracheal administration of BLM in anesthetized mice. Total lung collagen content was determined by hydroxyproline assay. The histopathological changes of pulmonary fibrosis were evaluated by image analysis.The secretion of 72,000 and 92,000 type IV collagenase in HT-1080 cell was markedly inhibited by doxycycline at concentrations of 0.1 mg/ml and 0.05 mg/ml. The activity of type IV collagenase in vitro was also suppressed by doxycycline. The hydroxyproline level in the lung was decreased in mice treated with doxycycline at the dose of 100 mg/kg, down to 34.7% of that of the BLM model group. As shown by image analysis, the extensiveness of fibrotic lesions, the thickness of interalveolar septa, and the accumulation of nucleated cells were decreased in doxycycline treated group in comparison with BLM model group.This study provides evidence that doxycycline shows inhibitory effect on BLM induced pulmonary fibrosis.

To study the mechanism of inhibition of basic fibroblast growth factor (bFGF) related signal transduction by lidamycin in cancer cells.MTT assay was used to determine the growth inhibitory effect of lidamycin (LDM) and adriamycin (ADR) in several cancer cell lines. The inhibition of bFGF bound to its receptor by LDM was measured with [125I]-bFGF binding assay. Intracellular Ca2+ stimulated by bFGF was measured by Fura-3. The formation of bFGF-receptor immune complex and the inhibitory effect of LDM on the activity of PKC isoenzymes induced by bFGF in cancer cells were identified by Western blotting analysis.LDM displayed extremely potent growth inhibitory effect on several cancer cell lines in a dose-dependent manner. A comparison of the IC50 values showed that the effect of LDM was 1000-fold more potent than that of ADR. LDM blocked the specific binding of [125I]-bFGF to rat lung membranes with an IC50 value of 2.0 x 10(-4) nmol x L(-1). As detected by anti-FGFR specific antibody, LDM inhibited the formation of bFGF-receptor immune complex. bFGF induced cytosolic Ca2+ response was obstructed by pretreatment with 10 nmol x L(-1) LDM. Immunoblotting demonstrated that LDM inhibited the activity of PKC isoenzymes in cancer cells stimulated with bFGF.The blocking of bFGF receptors in the signal transduction pathway may be involved in the effect of LDM on cancer cells.

AIM: Type IV collagenase including MMP-2 and -9 plays an important role in cancer cell invasion and metastasis and is an attractive target for mAb-directed therapy. The immunoreactivity of mAb 3G11, a mAb directed against type IV collagenase in human colorectal carcinomas, was studied by immuno-histochemical (IHC) staining. mAb 3G11 was conjugated to an antitumor antibiotic lidamycin (LDM). The antitumor activity of 3G11-LDM conjugate against colon carcinoma was investigated in mice. METHODS: ELISA, gelatin zymography, and Western blot assay were used for the biological characterization of mAb 3G11. The immunoreactivity of mAb 3G11 with human colorectal carcinomas was detected by IHC staining. The cytotoxicity of LDM and 3G11-LDM conjugate to human colon carcinoma HT-29 cells was examined by clonogenic assay and MTT assay. The therapeutic effect of conjugate 3G11-LDM was evaluated with colon carcinoma 26 in mice. RESULTS: As shown in ELISA, mAb 3G11 reacted specifically with type IV collagenase, while 3G11-LDM conjugate also recognized specifically its respective antigen. In IHC assay, mAb 3G11 showed positive immunoreactivity in most cases of colorectal carcinoma, and negative immunoreactivity in the adjacent non-malignant tissues. By gelatin zymography, the inhibition effect of mAb 3G11 on the secretion activity of type IV collagenase was proved. In terms of IC50 values in MTT assay, the cytotoxicity of LDM to human colon carcinoma HT-29 cells was 10 000-fold more potent than that of mitomycin C (MMC) and adriamycin (ADM). 3G11-LDM conjugate also displayed extremely potent cytotoxicity to human colon carcinoma HT-29 cells with an IC50 value of 5.610-19 mol/L. 3G11-LDM conjugate at the doses of 0.05 and 0.1 mg/kg inhibited the growth of colon carcinoma 26 in mice by 70.3 and 81.2%, respectively. CONCLUSION: mAb 3G11 is immunoreactive with human colorectal carcinoma and its conjugate with LDM is highly effective against colon carcinoma in mice.

AIM: To study the in vitro and in vivo antitumor effect of lidamycin (LDM) on hepatoma and the active moiety of its molecule. METHODS: MTT assay was used to determine the growth inhibition of human hepatoma BEL-7402 cells, SMMC-7721 cells and mouse hepatoma H22 cells. The in vivo therapeutic effects of lidamycin and mitomycin C were determined by transplantable hepatoma 22 (H22) in mice and human hepatoma BEL-7402 xenografts in athymic mice. RESULTS: In terms of IC50 values, the cytotoxicity of LDM was 10 000-fold more potent than that of mitomycin C (MMC) and adriamycin (ADM) in human hepatoma BEL-7402 cells and SMMC-7721 cells. LDM molecule consists of two moieties, an aproprotein (LDP) and an enediyne chromophore (LDC). In terms of IC50 values, the potency of LDC was similar to LDM. However, LDP was 105-fold less potent than LDM and LDC to hepatoma cells. For mouse hepatoma H22 cells, the IC50 value of LDM was 0.025 nmol/L. Given by single intravenous injection at doses of 0.1, 0.05 and 0.025 mg/kg, LDM markedly suppressed the growth of hepatoma 22 in mice by 84.7%, 71.6% and 61.8%, respectively. The therapeutic indexes (TI) of LDM and MMC were 15 and 2.5, respectively. By 2 iv. injections in two experiments, the growth inhibition rates by LDM at doses of 0.1, 0.05, 0.025, 0.00625 and 0.0125 mg/kg were 88.8-89.5%, 81.1-82.5%, 71.2-74.9%, 52.3-59.575%, and 33.3-48.3%, respectively. In comparison, MMC at doses of 5, 2.5, and 1.25 mg/kg inhibited tumor growth by 69.7-73.6%, 54.0-56.5%, and 31.5-52.2%, respectively. Moreover, in human hepatoma BEL-7402 xenografts, the growth inhibition rates by LDM at doses of 0.05 mg/kg × 2 and 0.025 mg/kg × 2 were 68.7% and 27.2%, respectively. However, MMC at the dose of 1.25 mg/kg × 2 showed an inhibition rate of 34.5%. The inhibition rate of tumor growth by LDM was higher than that by MMC at the tolerated dose. CONCLUSION: Both LDM and its chromophore LDC display extremely potent cytotoxicity to hepatoma cells. LDM shows a remarkable therapeutic efficacy against murine and human hepatomas in vivo.

Asiaticoside (ATS), a triterpene extracted from Centella asiatica (L.) Urban, a traditional Chinese herb, possesses good wound healing activities because of its stimulative effect on collagen synthesis. Recently, the anti-tumor effect of asiaticiside has been reported. This study was to examine the induction of apoptosis in cancer cells, and the enhancement of vincristine (VCR) cytotoxicity by asiaticoside.MTT assay was used to evaluate inhibitory effect of asiaticoside combined with vincristine on proliferation of several cancer cell lines, including KB, KBv200, MCF-7, and MCF-7/ADM. Cell cycle, and apoptosis of KB cells were analyzed by flow cytometry; apoptosis induction was also proved by electrophoresis,and morphologic assessment; the expression of apoptosis-, and cell cycle-related proteins were determined by Western blot.The IC(50) values of asiaticoside for KB, KBv200, MCF-7, and MCF-7/ADM cells detected by MTT assay were (1.11+/-0.13) mg/ml, (1.82+/-0.08) mg/ml, (1.58+/-0.15) mg/ml, and (3.25+/-0.46) mg/ml, respectively. Multidrug resistant KBv200, and MCF-7/ADM cancer cells displayed similar sensitivity to asiaticoside as their parental counterparts (KB, and MCF-7 cells). Moreover, asiaticoside induced apoptosis in KB cells. At sub-cytotoxicity concentration, asiaticoside showed synergistic effect with vincristine in these 4 cell lines. The apoptosis rates were much higher in asiaticoside plus vincristine groups than in vincristine or asiaticoside groups. Bcl-2 phosphorylation levels were higher in the combination groups than in vincristine or asiaticoside alone groups. The activated caspase-3 protein was only presented in the combination groups. Asiaticoside plus vincristine enhanced S-G(2)/M arrest, up-regulated Cyclin B1 protein expression, and down-regulated P34(cdc2) protein expression in KB cells.Asiaticoside, as a biochemical modulator, may induce apoptosis,and enhance anti-tumor activity of vincristine in cancer cells, might be useful in cancer chemotherapy.

Chemotherapy combined with other therapeutic modalities is the main option for advanced and metastatic soft tissue sarcoma(STS). So far there is no standard regimen for STS yet. Adrimycin, ifosfamide, and dacarbazine are the most effective agents at present. The purpose of this clinical trial was to evaluate the efficacy and toxicity of MAID regimen (mesna/ifosfamide + Adriamycin + dacarbazine) in the treatment of advanced soft tissue sarcoma.Twenty-two patients with advanced STS were treated by MAID(Adriamycin 60 mg/m2, ifosfamide 6,000 mg/m2, and dacarbazine 1,000 mg/m2). These drugs were administered as continuous intravenous infusion for 72 hours while mesna was infused continuously for 96 hours.Partial response rate was 36.4% without complete remission. The duration of response ranged from 2-10 months with median of 4.6 months. Main toxicities were myelosuppression, gastrointestinal toxicity and alopecia. Percentage of leucopenia, nausea/vomiting, and alopecia in WHO grade III and IV were 63.6%, 27.3%, and 50%, respectively.The response rate of MAID for advanced STS was not satisfactory with evident myelosuppression. Further study on new anti-cancer agents and regimen are needed.