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A series of nanomaterials have been demonstrated to be powerful for direct degradation of diethyl paraoxon (EP) to diethyl phosphate and 4-nitrophenol in aqueous solution. However, comparison of catalytic activity of different nanomaterials toward EP is rarely explored. In the present study, four different morphological nanoceria (cubes, rods, polyhedral, and spheres) were synthesized, characterized, and evaluated as a catalyst for the degradation of EP in comparison to other commercially available nanomaterials. Among the tested nanoceria, the cerium dioxide (CeO 2 ) nanopolyhedra possess the best catalytic activity toward the hydrolysis of EP owing to their abundant oxygen vacancy sites, optimal ratio of Ce(III) to Ce(IV), and specific exposed facets. Under the conditions of 0.2 M NH 3 /NH 4 Cl buffer and 25 °C, the CeO 2 nanopolyhedra catalyzed the reduction of EP to 4-nitrophenol with a >99% conversion at pH 8.0 for 50 h, at pH 10.0 for 12 h, and at pH 12.0 for 2.5 h. The catalytic degradation of nearly 100% EP in NH 3 /NH 4 Cl buffer (pH 10.0) at 25 °C is in the decreasing order of CeO 2 nanopolyhedra > CeO 2 nanorods > ZnO nanospheres (NSs) > CeO 2 nanocubes > TiO 2 NSs > CeO 2 NSs > Fe 3 O 4 NSs ~ Co 3 O 4 NSs ~ control experiment. The mechanism for the degradation of EP was confirmed by monitoring catalytic kinetics of the CeO 2 nanopolyhedra in the presence of EP, dimethyl paraoxon, 4-nitrophenyl phosphate, and parathion. The nanocomposites were simply fabricated by electrostatic self-assembly of the CeO 2 nanopolyhedra and poly(diallyldimethylammonium chloride)-capped gold nanoparticles (PDDA-AuNPs). The resultant nanocomposites still efficiently catalyzed NaBH 4 -mediated reduction of 4-nitrophenol to 4-aminophenol with a normalized rate constant of 6.68 ± 0.72 s -1  g -1 and a chemoselectivity of >99%. In confirmation of the robustness and applicability of the as-prepared nanocomposites, they were further used to catalyze the degradation of EP to 4-amionphenol in river water and seawater., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Using the techniques of computer-aided drug design, the docking of survivin and known active small molecules was simulated and then the key amino acid residue fragments of the target protein were analyzed. It led to the discovery of active groups capable of binding to the critical sites. Through the use of the natural product, oleanolic acid, as a lead compound, the introduction of the active groups onto the A-ring, and the modification of the carboxyl group at the C-28 position using esterification or amidation, 20 new oleanolic acid derivatives had been designed and synthesized. HepG2 and SGC-7901 cells were used to screen the antitumor activity through the standard MTT method. The compounds, II 3 , III 5 and IV 4, exhibited more potent cytotoxicity than positive drugs. Western blot experiment demonstrated that compound II 3 can effectively inhibit the proliferation of HepG2 cells.

Citrate-capped gold nanoparticles (AuNPs) modified with thrombin-binding aptamer are often implemented for colorimetric, fluorescent, and electrochemical detection of thrombin in an aqueous solution. However, researchers have rarely explored the application of fibrinogen-modified AuNPs (F-AuNPs) for thrombin sensing. We present a simple, inexpensive, sensitive, and selective probe for colorimetric assay of thrombin through combining thrombin-induced inclusion of F-AuNPs into Fibrin and F-AuNPs-catalyzed reduction of 4-nitrophenol with an excess amount of NaBH 4 . Considering that fibrinogen stabilized citrate-capped AuNPs against a high-ionic-strength buffer, F-AuNPs efficiently catalyzed the NaBH 4 -mediated decrease of yellow 4-nitrophenol to colorless 4-aminophenol. The presence of thrombin converted fibrinogen into fibrin on the nanoparticle surface, leading to the inclusion of nanoparticles into fibrin. The formation of fibrin inhibited that the AuNPs catalyzed the NaBH 4 -mediated reduction of 4-nitrophenol. Consequently, the color of the solution gradually varied from colorless to yellow with increasing thrombin concentration. The proposed system was shown to be accurate in the quantification of small differences in the concentration of human thrombin over the range of 4-60 pM. The lowest detectable concentration of human thrombin by the naked eye was as low as 16 pM. We demonstrated the practical application of the proposed system in quantifying 1-15 nM human thrombin in human plasma., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Objective: According to results from the two-month consecutive surveillance program in Maanshan, six suspected cases of non-O1 non-O139 Vibrio (V.) cholerae infection, were found that called for identification of pathogens as well as molecular-epidemiological analysis to determine the aggregation of the epidemic situation., Methods: Biochemical and serotype identification, hemolysis test, and drug sensitive test were used to detect the drug resistance spectrum. Real-time PCR and conventional PCR were used to detect the presence of V. cholerae specific genes, virulent genes and its related genes, including ompW, ctx, tcpA, toxR, hlyA, zot, ace, rstR and gIII(CTX). Pulsed-field gel electrophoresis (PFGE) was used to analyze the molecular type of strains., Results: All the six isolates of non-O1 non-O139 V. cholerae were identified by biochemical and serologic tests, and appeared to be β hemolytic. Twelve out of the 14 kinds of drugs showed 100% sensitive. All isolates were positive of ompW gene by real-time PCR, but negative for ctx, tcpA, zot, ace, rstR and gIII(CTX). Five of the six isolates were positive for toxR and hlyA, except for strain 1001434446. All strains had different PFGE types, but two strains had similar types. All strains had a low similarity compared to the toxigenic V. cholerae., Conclusion: Six cases of non-O1 and non-O139 nontoxigenic V. cholerae infection appeared in the same period. Along with epidemiological information, we noticed that these cases had a sporadic nature, but frequently appeared in the same area. We got the impression that public health measurements should be strengthened, with special attention paid to those diarrhea outbreaks caused by non-O1/non-O139 strains since V. cholerae had appeared in low incidence.

Aim: To investigate the seroprevalence and molecular characteristics of hepatitis E virus (HEV) in the illegal blood donors (IBDs) of central China in the early 1990s., Methods: A total of 546 blood samples were collected from the IBDs in Maanshan city, a questionnaire was completed by each subject, detailing the age, sex, and periods of blood or plasma donation. Anhui Province and tested for the anti-HEV antibodies. The seropositive samples were subjected to nested reverse transcription-polymerase chain reaction and sequencing to analyze HEV partial genome., Results: The prevalence of IgG and IgM HEV antibody in IBDs was 22.7% and 1.8%, and genotype 4 was the dominant circulating HEV type in IBDs. The prevalence of anti-HEV IgG was significantly related to sex (OR = 4.905, P = 0.004) and increased with age (OR = 2.78, P = 0.022), which ranged from 13.0% in those < 40 years old to 30.6% among older persons aged > 60 years. Moreover, frequency of blood donation was significantly associated with HEV seropositivity (OR = 2.06, P = 0.006). HEV partial sequences of ORF2 and obtained 3 sequences in serum samples of 10 IBDs which developed HEV specific IgM., Conclusion: This study helps define one of the possible routes of transmission of sporadic HEV infection and provides guidance to screen HEV in the blood donors so as to guarantee safe blood banks in China.

The pathogenicity to wheat (Pwt1) locus conditions host species specificity of Magnaporthe oryzae on wheat. GFSI1-7-2 (Setaria isolate) carries the avirulence allele (PWT1) at this locus while Br48 (Triticum isolate) carries the virulence allele (pwt1). An F(1) culture derived from a cross between GFSI1-7-2 and Br48 was backcrossed with Br48 to produce a tester population in which PWT1 alone segregated. When hexaploid wheat lines were inoculated with the BC(1)F(1) testers, they were all resistant to all PWT1 carriers and susceptible to all pwt1 carriers, suggesting that they recognize PWT1. When barley cultivars were inoculated with the testers, they showed the same pattern of reactions as the hexaploid lines, suggesting that the barley cultivars also recognize PWT1. These results suggest that PWT1 is a fundamental gene that universally conditions the avirulence of Setaria isolates on two staple crops, hexaploid wheat and barley. Interestingly, tetraploid wheat lines did not recognize PWT1. Molecular mapping using the F(1) and BC(1)F(1) populations revealed that the Pwt1 locus is located on chromosome 2 and tightly linked to the ribosomal DNA locus and a telomere.

Objective: To identify the isolates of Shewanella spp. from specimens of food poisoning based on biological and biochemical analysis., Methods: Strains were obtained from the investigation on two food poisoning episodes in September and October, 2007 in Ma'anshan city, Anhui province. In accordance with the national standard protocol (GB/T 4789), all specimens were enriched and isolated on selective medium, and the suspected strains were identified by the VITEK-32 and API20E systems. For Shewanella spp. identified by the biochemical system, more characteristics were analyzed using auxiliary biochemical, growth, hemolytic and drug-resistance tests. DNAs of Shewanella spp. were extracted, 16S rDNA was PCR amplified and sequenced with universal 16S rDNA primers. Phylogenetic tree was constructed with MEGA 4.0., Results: After enrichment, all specimens were inoculated to selective medium and Shewanella spp. strains were isolated from 8 samples with single colony on both TCBS and BP media. The characteristics of growth in the Triple Sugar Iron (TSI) agar appeared to have had hydrogen sulfide production but no gas production or positive oxidase. No Shewanella spp. strain was detected in WS, SS and EMB media. The 8 strains were identified as Shewanella algae (S. algae) or Shewanella putrefaciens (S. putrefaciens) by VITEK-32, as S. putrefaciens by API20E system. No other enteropathogenic bacteria, including Vibrio cholerae, Salmonella, Vibrio parahaemolyticus, Proteus vulgaris or Staphylococcus aureus, were detected from those 8 samples. From 16S rDNA phylogenetic trees, 7 out of 8 Shewanella spp. were identified as S. algae, 1 as S. putrefaciens., Conclusion: Strains of Shewanella spp. were isolated from samples of the food poisoning episodes, providing a possible clue to investigate the role of Shewanella spp. on food poisoning.

Background and Aim: To investigate a possible association between HLA genes with serum alanine aminotransferase (ALT) levels and evaluate whether the HLA-DQA1, DQB1, and DRB1 genes could influence the development of liver damage in chronic hepatitis C., Methods: A total of 145 patients with chronic hepatitis C virus (HCV) infection (36 patients with persistently normal ALT values; 109 patients with elevated ALT levels) and 160 uninfected healthy controls were examined for HLA-DQA1, DQB1, and DRB1 molecules by using polymerase chain reaction-sequencing based typing (PCR-SBT)., Results: Among the patients chronically infected with HCV, the frequencies of DQA1*0501, DQB1*0301, and DRB1*0401 alleles were significantly increased in the normal ALT group compared with those with abnormal ALT levels, whereas that of DQB1*0201 was significantly lower. As compared to uninfected healthy controls, DQA1*0501, DQB1*0301, and DRB1*0401 allele frequencies were also statistically higher in the normal ALT group, whereas that of DQB1*0201 was the inverse. The haplotype frequencies of DQA1*0301-DQB1*0301, DQA1*0501-DQB1*0301, and DRB1*1101-DQB1*0301 were found to be significantly higher in the normal ALT group. Multivariate logistic regression indicated that female sex, and the DQB1*0301 allele and DRB1*0401 allele were independently associated with normal ALT values, whereas DQB1*0201 allele was the inverse., Conclusions: These results suggest that particular HLA alleles may have an influence on the serum ALT level of chronic HCV infection as a host genetic factor in the Chinese population. The DQA1*0501, DQB1*0301, and DRB1*0401 alleles, and the DQA1*0301-DQB1*0301, DQA1*0501-DQB1*0301, and DRB1*1101-DQB1*0301 haplotypes seem to be associated with low hepatitis activity; whereas DQB1*0201 allele is closely correlated with the progression of liver injury in chronic HCV infection.

A screening of common wheat cultivars revealed that Triticum aestivum 'Thatcher' was resistant to Triticum isolates of Magnaporthe oryzae, whereas T. aestivum 'Chinese Spring' was susceptible. When F2 seedlings from a cross between 'Thatcher' and 'Chinese Spring' were inoculated with the Triticum isolates, resistant and susceptible seedlings segregated in a 15:1 ratio, suggesting that the resistance of 'Thatcher' was conditioned by two major genes. An inoculation test of 'Chinese Spring' substitution lines carrying individual chromosomes from 'Thatcher' indicated that these genes, designated Rmg2 and Rmg3, were located on chromosomes 7A and 6B.

In this study, we retrospectively analyzed 18 patients in whom antithyroid drug (ATD)-induced agranulocytosis developed during treatment of Graves' disease. All patients were more than 20 years of age, and we saw no correlation between age and the development of agranulocytosis. In 17 of 18 patients, ATD-induced agranulocytosis developed within 2 to 12 weeks of starting ATD treatment. Development of agranulocytosis was related to the dose of ATD. In some patients, agranulocytosis developed abruptly, and even weekly routine WBC and granulocyte counts failed to predict all case occurrences. Fever and sore throat were the earliest symptoms of agranulocytosis; patients who developed either of these symptoms were closely monitored immediately with WBC and granulocyte count examinations. In this series of patients, treatment with granulocyte-macrophage colony stimulating factor (GM-CSF) increased the granulocyte counts, whereas the effectiveness of glucocorticoid treatment was not confirmed.