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1.
Plant Dis ; 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36627799

RESUMO

Tetrapanax papyriferus is an evergreen shrub native to China and traditionally used as a herbal medicine (Li et al., 2021). In September 2021, a serious leaf spot disease with symptoms similar to anthracnose was extensively observed on T. papyriferus in Shibing county (E 127°12'0", N 25°11'60"), Qiandongnan Miao and Dong Autonomous Prefecture, Guizhou province, China. Field surveys were conducted in about 1000 T. papyriferus plants in Shibing in September 2021. The incidence of the leaf spot on leaves was 45% to 60%, significantly reducing the quality of medicinal materials. The symptoms began as small yellow spots, developing a brown center and dark brown to black margin, and eventually the diseased leaves were wiltered and rotted. Symptomatic leaves were collected from 20 trees. Symptomatic tissue from diseased leaves was surface desinfected (0.5 min in 75% ethanol and 1 min in 3% NaOCl, washed three times with sterilized distilled water), small pieces of symptomatic leaf tissue (0.2 × 0.2 cm) were plated on potato dextrose agar (PDA) and incubated at 25°C for about 7 days (Fang. 2007). Three single-spore isolates were obtained (GUTC37, GUTC310 and GUTC311) and deposited in the collection of the Plant Pathology Deparment, College of Agriculture, Guizhou University, China (GUCC) (with the accession numbers, GUCC220241, GUCC220242, GUCC220243 respectively). These isolates were identical in morphology and in the sequences of internal transcribed spacer region [ITS], glyceraldehy-3-phosphate dehydrogenase [GAPDH], chitin synthase [CHS-1], actin [ACT], and calmodulin [CAL] genes (White et al. 1990; Carbone and Kohn 1999; Templeton et al. 1992). Therefore, the representative isolate GUTC37 was used for further analysis. The pathogenicity of GUTC37 was tested through a pot assay. Plants were inoculated by spraying a spore suspension (106 spores·ml-1) of isolated strains onto leaves until runoff, and the control leaves sprayed with sterile water. The inoculated plants were incubated in a growth chamber at 28 ℃ and 95% relative humidity for 10 days. Pathogenicity tests were repeated three times (Fang. 2007). The symptoms developed on the inoculated leaves, while control remained asymptomatic. The lesions were first visible 72 h after inoculation, and typical lesions like those observed on field plants appeared after 10 days. The same fungus was reisolated and identified based on the morphological characterization and molecular analyses from the infected leaves but not from the non-inoculated leaves. Results of pathogenicity experiments of isolated fungi fulfilled Koch's postulates. Fungal colonies on PDA were villiform, creamy-white or greyish, aerial mycelium pale grey, dense, surface partly covered with orange conidial masses. The conidia were abundant, oval-ellipsoid, aseptate, and 13.89 (11.62 to 15.21) × 5.21 (4.39 to 5.65) µm (n=50). Appressorium were greyish green, nearly ovoid to cylindrical, 9.64 (6.62 to 14.61) × 6.33 (5.45-7.72) µm (n=50). The morphological features were consistent with the descriptions of Colletotrichum fructicola Prihast., L. Cai & K.D. Hyde (Prihastuti et al. 2009). The pathogen was identified to be C. fructicola by amplification and sequencing of the five genes. The sequences of the PCR products were deposited in GenBank with accession numbers OP143657 (ITS), OP177868 (GAPDH), OP177865 (CHS-1), OP278677 (ACT) and OP177862 (CAL). BLAST searches of the obtained sequences revealed 100% (509/509 nucleotides), 99.63% (269/270 nucleotides), 99.31% (287/289 nucleotides), 99.29% (280/282 nucleotides), and 99.86% (728/729 nucleotides) homology with those of C. fructicola in GenBank (JX010165, JX010033, JX009866, FJ907426, and JX009676, respectively). Phylogenetic analysis (MEGA 7.0) using the maximum likelihood method placed the isolate GUTC37 in a well-supported cluster with C. fructicola. To our knowledge, this is the first report of anthracnose on T. papyriferus caused by C. fructicola in Guizhou, China. This study provides valuable information for the identification and control of the anthracnose on T. papyriferus.

2.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(1): 78-83, 2021 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-33476542

RESUMO

OBJECTIVE: To study the effect of calorie-enriched formula on postoperative catch-up growth in infants with cyanotic congenital heart disease (CHD). METHODS: A total of 100 infants with cyanotic CHD who underwent surgical operation from January to December, 2017, were randomly divided into a high-calorie group (receiving calorie-enriched formula after surgery) and a conventional group (receiving standard formula after surgery), with 50 infants in each group. All infants were followed up for 6 months. The observation indices included body height, body weight, prealbumin, and N-terminal pro-brain natriuretic peptide before surgery, at the time of ventilator weaning and extubation after surgery, and at 1, 3, and 6 months after surgery. Height-for-age Z-score (HAZ), weight-for-age Z-score (WAZ), and weight-for-height Z-score (WHZ) were also assessed. Adverse reactions were recorded for both groups. RESULTS: There were 25 cases (50%) and 21 cases (42%) of malnutrition in the high-calorie group and the conventional group respectively before surgery (P > 0.05). The nutritional status of the two groups improved 6 months after surgery (P < 0.05). At 6 months after surgery, compared with the conventional group, the high-calorie group had a lower proportion of infants with malnutrition (18% vs 36%, P < 0.05) and also a lower proportation of infants with a WAZ score of < -2 (P < 0.05). The infants with malnutrion in the high-calorie group had higher HAZ, WAZ, and WHZ than those in the conventional group (P < 0.05). No gastrointestinal intolerance was observed in both groups during hospitalization. CONCLUSIONS: Compared with the standard formula, calorie-enriched formula can better help with postoperative catch-up growth in infants with cyanotic CHD.


Assuntos
Cardiopatias Congênitas , Peso Corporal , Ingestão de Energia , Cardiopatias Congênitas/cirurgia , Humanos , Lactente , Desnutrição , Estado Nutricional , Estudos Prospectivos
3.
Microb Pathog ; 148: 104492, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32916243

RESUMO

After sequence comparison, it was found that there are multiple amino acid mutations in pre-M and envelope (E) protein of Japanese encephalitis virus vaccine strain comparison with wild type (WT) strain SA14. It is generally acknowledged it is the mutations that have caused the virulence attenuation of vaccine strain, but lack of sufficient experimental evidences. For a better understanding of the mechanism of attenuation of Japanese encephalitis virus (JEV), in this study, we assessed whether prM/E is critical neurovirulence determinants of JEV with infectious cDNA clones technique. Substitutions prM/E of vaccine strain with that of WT SA14 did significantly increase the virulence of JEV to the similar level of wild type SA14, and simultaneously, replacement prM/E of JEV WT strain SA14 with that of vaccine strain SA14-14-2 decreased the virulence of JEV significantly to the similar level of vaccine stain. The results indicate that the prM/E protein is the crucial virulence determinant of Japanese encephalitis virus, although other proteins take part in the process to some extent.


Assuntos
Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , Vírus da Encefalite Japonesa (Espécie)/genética , Humanos , Vacinas Atenuadas , Proteínas do Envelope Viral/genética , Virulência
4.
Front Med (Lausanne) ; 11: 1329538, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38741763

RESUMO

Objective: To explore the effect of applying the online to offline teaching mode in the training of non-anesthesiology residents in department of anesthesiology. Trial design: The randomized controlled trial was performed on non-anesthesiology residents from Affiliated Jiangning Hospital of Nanjing Medical University. Methods: All selected residents were randomly divided into the traditional teaching group (Group T) and the online to offline teaching group (Group O) by the random number table method. Traditional teaching mode was used in Group T, while the online to offline teaching mode was used in Group O. The training period lasted for two months. At the end of the training, theoretical and clinical skills were assessed for all residents, and students' satisfaction scores on teaching were investigated from the aspects of teaching mode, stimulating learning interest, improving learning process and teaching satisfaction. The teaching efficiency was compared and analyzed in the two groups. Results: In total, 39 cases in Group O and 38 cases in Group T were included in the statistical analysis. Compared with Group T, theory test scores, clinical skills test scores, and overall scores improved significantly in Group O (82.2 ± 8.1 vs. 91.3 ± 7.6; 85.1 ± 4.7 vs. 93.3 ± 5.4 and 83.4 ± 6.4 vs. 92.1 ± 6.7, respectively, p < 0.01). Compared with Group T, scores on teaching mode, stimulating learning interest, improving learning process and teaching satisfaction were higher in Group O (81.1 ± 6.9 vs. 93.7 ± 5.2; 83.6 ± 5.8 vs. 91.6 ± 6.4; 82.4 ± 5.3 vs. 90.9 ± 4.8 and 82.1 ± 5.9 vs. 92.1 ± 5.5, respectively, p < 0.01). Conclusion: The online to offline teaching mode can improve the level of professional theory and clinical skill operation, and teaching satisfaction of the non-anesthesiology residents in department of anesthesiology, thus improving the teaching effectiveness.

5.
Insects ; 13(2)2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-35206714

RESUMO

Due to a lack of effective internal references, studies on functional genes in Phthorimaea operculella, a serious Lepidopteran pest attacking potatoes worldwide, have been greatly limited. To select suitable endogenous controls, ten housekeeping genes of actin (ACT), α-tubulin (α-TUB), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), elongation factor 1α (EF1α), 18S and 28S ribosomal RNA (18S, 28S), ribosomal protein genes RPL4, RPL13 and RPL27 and superoxide dismutase (SOD) were tested. Their expression levels were determined under three different experimental conditions (developmental stages, tissues/organs and temperatures) using qRT-PCR technology. The stability was evaluated with five methods (Ct value, geNorm, NormFinder, BestKeeper and RefFinder). The results clarified that RPL13, EF1α and RPL27 are ranked as the best reference gene combination for measuring gene expression levels among different developing stages and under various temperatures; EF1α and RPL13 are recommended to normalize the gene expression levels among diverse tissues. EF1α and RPL13 are the best reference genes in all the experimental conditions. To validate the utility of the selected reference pair, EF1α and RPL13, we estimated the tissue-biased expression level of chitin synthase A gene (PoChSA). As expected, PoChSA was abundantly expressed in ectodermally derived epidermal cells, and lowly transcribed in the midgut. These findings will lay the foundation for future research on the molecular physiology and biochemistry of P. operculella.

6.
Microbiol Immunol ; 55(4): 247-53, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21272063

RESUMO

Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is associated with hemorrhagic colitis, thrombotic thrombocytopenic purpura, and hemolytic-uremic syndrome in humans. B-cell epitopes of intimin γ from EHEC O157:H7 were predicted and synthesized for evaluating their immunogenicity and protective effect and for screening a novel synthetic peptide vaccine. In the present study, five B-cell epitopes of IntC300 were predicted by Hopp-Woods, Chou-Fasman, Karplus-Schulz, Emini, Jameson-Wolf and Kolaskar-Tongaonakar analysis. One of them, KT-12 (KASITEIKADKT) was coupled with keyhole limpet hemocyanin, and used to immunize BALB/c mice three times by subcutaneous and intranasal injection. Mouse serum titers of IgG and IgA were assessed by indirect ELISA. Oral inoculation of EHEC O157:H7 resulted in infection and death of the mice. It was found that B-cell epitopes are located within or near the peptide segments 658-669, 711-723, 824-833, 897-914, 919-931. Both subcutaneous and intranasal immunization induced higher concentrations of IgG antibodies, as detected by indirect ELISA, and nasal-mucosal immunization induced the production of high concentrations of IgA antibodies. After infection with a lethal dose of EHEC O157:H7, the survival rate of mice that had received subcutaneous immunization was not significantly different from that of the control group (P > 0.05). On the other hand, mice that received intranasal immunization showed a better survival rate than the group that received subcutaneous immunization (P < 0.05). The synthesized antigenic peptide KT-12 induced mice to produce higher concentrations of IgG and IgA after immunization, but only intranasal immunization of KT-12 succeeded in protecting most mice from infection with EHEC O157:H7. This study suggests that the synthesized antigenic peptide KT-12 is be a potential vaccine candidate against EHEC O157:H7.


Assuntos
Adesinas Bacterianas/imunologia , Epitopos de Linfócito B/imunologia , Infecções por Escherichia coli/imunologia , Escherichia coli O157/imunologia , Proteínas de Escherichia coli/imunologia , Vacinas contra Escherichia coli/imunologia , Adesinas Bacterianas/administração & dosagem , Adesinas Bacterianas/química , Sequência de Aminoácidos , Animais , Anticorpos Antibacterianos/imunologia , Mapeamento de Epitopos , Epitopos de Linfócito B/administração & dosagem , Epitopos de Linfócito B/química , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/prevenção & controle , Escherichia coli O157/fisiologia , Proteínas de Escherichia coli/administração & dosagem , Proteínas de Escherichia coli/química , Vacinas contra Escherichia coli/administração & dosagem , Vacinas contra Escherichia coli/química , Feminino , Humanos , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular
7.
Chem Commun (Camb) ; 57(43): 5258-5261, 2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-33969840

RESUMO

Herein, we report a one-step synthesis of a hollow Fe-N/C catalyst via a hard-templating strategy, in which FeNx sites are well dispersed on the carbon sphere. In particular, we found an optimal iron ratio on the catalyst surface for an enhanced alkaline oxygen reduction reaction (ORR). The catalyst with a high specific surface area of 311.71 m2 g-1 exposes abundant electroactive sites that facilitate the adsorption of oxygen intermediates, thus exhibiting superior ORR activity in alkaline solution.

8.
RSC Adv ; 11(32): 19406-19416, 2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35479235

RESUMO

Developing a low-cost, simple, and efficient method to prepare excellent bifunctional electrocatalysts toward the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is critical in rechargeable zinc-air batteries. Non-stoichiometric M0.85Se (M = Ni or Co) nanoparticles are synthesized and modified on nitrogen-doped hollow carbon sphere (NHCS). The NHCS loaded Ni0.85Se (Ni0.85Se-NHCS) with rich Ni3+ presents higher OER activity, whereas the NHCS-loaded Co0.85Se (Co0.85Se-NHCS) with abundant Co2+ displays better ORR activity, respectively. When Co0.85Se-NHCS is mixed with Ni0.85Se-NHCS in a mass ratio of 1 : 1, the resulting mixture (Ni0.85Se/Co0.85Se-NHCS-2) shows better ORR and OER dual catalytic functions than a single selenide. Moreover, zinc-air batteries equipped with Ni0.85Se/Co0.85Se-NHCS-2 as the oxygen electrode catalyst exhibit excellent charge and discharge performance as well as improved stability over precious metals. This work has developed a simple and effective method to prepare excellent bifunctional electrocatalysts for ORR and OER, which is beneficial for the practical large-scale application of zinc-air batteries.

9.
J Phys Chem B ; 120(44): 11510-11522, 2016 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-27786467

RESUMO

The first-principles method is challenged by accurate prediction of van der Waals interactions, which are ubiquitous in nature and crucial for determining the structure of molecules and condensed matter. We have contributed to this by constructing a set of pseudopotentials and pseudoatomic orbital basis specialized for molecular systems consisting of C/H/N/O elements. The reliability of the present method is verified from the interaction energies of 45 kinds of complexes (comparing with CCSD(T)) and the crystalline structures of 23 kinds of typical explosive solids (comparing with experiments). Using this method, we have studied the phase transition of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) under static compression up to 50 GPa. Kinetically, intramolecular deformation has priority in the competition with intermolecular packing deformation by ∼87%. A possible γ → ß phase transition is found at around 2.10 GPa, and the migration of H2O has an effect of kinetically pushing this process. We make it clear that no ß â†’ δ/ε → δ phase transition occurs at 27 GPa, which has long been a hot debate in experiments. In addition, the P-V relation, bulk modulus, and acoustic velocity are also predicted for α-, δ-, and γ-HMX, which are experimentally unavailable.

10.
Food Chem ; 197(Pt A): 161-7, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26616936

RESUMO

Green tea, oolong tea and black tea were separately introduced to brew three kinds of tea beers. A model was designed to investigate the tea beer flavour character. Comparison of the volatiles between the sample of tea beer plus water mixture (TBW) and the sample of combination of tea infusion and normal beer (CTB) was accomplished by triangular sensory test and HS-SPME GC-MS analysis. The PCA of GC-MS data not only showed a significant difference between volatile features of each TBW and CTB group, but also suggested some key compounds to distinguish TBW from CTB. The results of GC-MS showed that the relative concentrations of many typical tea volatiles were significantly changed after the brewing process. More interestingly, the behaviour of yeast fermentation was influenced by tea components. A potential interaction between tea components and lager yeast could be suggested.


Assuntos
Cerveja/análise , Camellia sinensis/química , Aromatizantes/análise , Saccharomyces cerevisiae/crescimento & desenvolvimento , Chá/química , Compostos Orgânicos Voláteis/análise , Cerveja/microbiologia , Fermentação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Paladar
11.
Colloids Surf B Biointerfaces ; 129: 206-10, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25863711

RESUMO

Poly(vinyl acetate-acrylamide) microspheres with an average diameter of 2-4µm were successfully prepared and characterized via SEM and FTIR. Then the microspheres were modified with epoxy groups through reacting with epichlorohydrin and used as carriers to covalently immobilize Candida rugosa lipase. The results revealed that agitation played an important role on epoxy activation and the immobilization ratio increased with the increase of the epoxy density. On the other hand, the specific activity of the immobilized lipase as well as the activity recovery declined gradually with the increase in the immobilization ratio from 72% to 93%, which were attributed to the steric hindrance effects caused by enzyme overloading. When epoxy density was 76µmol/g microsphere, the activity recovery reached the maximum at 47.5%, and the activity of the immobilized lipase was 261.3U/g microsphere. Moreover, the thermal stability of the immobilized lipase was much better than that of the free one, which indicated potential applications of the immobilized lipase.


Assuntos
Acrilamida/química , Candida/enzimologia , Enzimas Imobilizadas/metabolismo , Resinas Epóxi/química , Lipase/metabolismo , Microesferas , Polivinil/química , Estabilidade Enzimática , Enzimas Imobilizadas/química , Ácidos Graxos/metabolismo , Concentração de Íons de Hidrogênio , Lipase/química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
12.
J Pharm Biomed Anal ; 30(3): 667-73, 2002 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-12367692

RESUMO

A poly (vinyl chloride) membrane electrode with dibutyl phthalate as plasticizer based on the fentanyl-phosphotungstate ion-association complex as ion-exchange site for the determination of fentanyl citrate in injections was developed. A linear response for 1 x 10(-5)-1 x 10(-2) mol dm(-3) drug with a slope of 55.9 +/- 0.4 mV per decade was established. The optimum pH range was 1-7. The lower detection limit was 5.43 x 10(-6) mol dm(-3) fentanyl citrate (1.827 microg cm(-3), 2.33 x 10(-6) mol dm(-3) fentanyl). There were negligible interference from a number of inorganic cations, structural analogues, and some common drug additives in injections. The electrode proposed had been successfully applied to determine fentanyl citrate in injections. The results correlated well with those obtained by the United States Pharmacopoeia standard procedure.


Assuntos
Fentanila/análise , Química Farmacêutica , Potenciometria/métodos
13.
J Zhejiang Univ Sci B ; 13(2): 83-93, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22302421

RESUMO

Fatty acids and derivatives (FADs) are resources for natural antimicrobials. In order to screen for additional potent antimicrobial agents, the antimicrobial activities of FADs against Staphylococcus aureus were examined using a microplate assay. Monoglycerides of fatty acids were the most potent class of fatty acids, among which monotridecanoin possessed the most potent antimicrobial activity. The conventional quantitative structure-activity relationship (QSAR) and comparative molecular field analysis (CoMFA) were performed to establish two statistically reliable models (conventional QSAR: R(2)=0.942, Q(2)(LOO)=0.910; CoMFA: R(2)=0.979, Q(2)=0.588, respectively). Improved forecasting can be achieved by the combination of these two models that provide a good insight into the structure-activity relationships of the FADs and that may be useful to design new FADs as antimicrobial agents.


Assuntos
Anti-Infecciosos/farmacologia , Ácidos Graxos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Anti-Infecciosos/química , Ácidos Graxos/química , Testes de Sensibilidade Microbiana , Modelos Moleculares , Análise de Componente Principal , Relação Quantitativa Estrutura-Atividade , Distribuição Aleatória , Staphylococcus aureus/crescimento & desenvolvimento
14.
Nan Fang Yi Ke Da Xue Xue Bao ; 29(4): 707-10, 2009 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-19403401

RESUMO

OBJECTIVE: To obtain highly purified intimin encoded by the eae gene and study its adhesion activity. METHODS: The eae gene was amplified from enterohemorrhagic Escherichia coli O157:H7 (EHEC) chromosome by PCR and cloned into pMD19-T vector. The eae gene was cut from pMD19-T vector and subcloned into the prokaryotic expression plasmid pET28a(+), and expressed in E.coli BL21(DE3). The recombinant protein was purified with Ni(2+)-chelating affinity chromatography followed by identification with SDS-PAGE and Western blotting. The purified intimin was detected by immunofluorescence staining to test its adhesion. RESULTS: The 2805-bp eae gene fragment was obtained, and the recombinant expression plasmid pET28a(+)-eae was successfully expressed in E.coli BL21 (DE3). The molecular weight of the recombinant protein was 97 000. Purified recombinant intimin was recognized by rabbit anti-O157 antiserum, and bound to the surface of HEp-2 cells as revealed by immunofluorescence staining. CONCLUSION: Highly purified and immunoreactive intimin has been successfully obtained, which can adhere to the surface of HEp-2 cells. The acquisition of recombinant intimin provides the basis for studying its interaction with the host receptors during EHEC O157:H7 infection.


Assuntos
Adesinas Bacterianas/genética , Adesinas Bacterianas/metabolismo , Escherichia coli O157 , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Escherichia coli/genética , Adesinas Bacterianas/biossíntese , Adesinas Bacterianas/isolamento & purificação , Animais , Western Blotting , Adesão Celular , Linhagem Celular , Clonagem Molecular , Proteínas de Escherichia coli/biossíntese , Proteínas de Escherichia coli/isolamento & purificação , Expressão Gênica , Plasmídeos/genética
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