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1.
J Hypertens ; 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32141967

RESUMO

BACKGROUND: Smokers may smoke cigarettes during ambulatory or home blood pressure (BP) monitoring but not clinic measurement. We investigated the prevalence of masked hypertension in relation to cigarette smoking in Chinese outpatients enrolled in a multicenter registry. METHODS: Our study included 1646 men [494 (30.0%) current smokers]. We defined masked hypertension as a normal clinic SBP/DBP (<140/90 mmHg) and elevated daytime (≥135/85 mmHg) or night-time (≥120/70 mmHg) ambulatory or morning or evening home SBP/DBP (≥135/85 mmHg). RESULTS: In all men, multiple logistic regression showed that current cigarette smoking was significantly associated with daytime [prevalence 18.7%, odds ratio (OR) 1.69, 95% confidence interval 1.27-2.25, P = 0.0003] but not night-time (prevalence 27.1%, P = 0.32) ambulatory masked hypertension and associated with evening (prevalence 14.6%, OR 1.81, confidence interval 1.33-2.47, P = 0.0002) but not morning (prevalence 17.6%, P = 0.29) home masked hypertension. The associations were more pronounced for heavy smoking (≥20 cigarettes/day) relative to never smoking for both masked daytime ambulatory (OR 1.97, P = 0.001) and evening home hypertension (OR 2.40, P < 0.0001) or in patients over 55 years of age (P for interaction in relation to daytime ambulatory masked hypertension = 0.005). In men with clinic normotension (n = 742), the associations were also significant (P < 0.01), particularly in those with a normal to high-normal clinic BP (n = 619, P < 0.04). CONCLUSION: Cigarette smoking was associated with increased odds of masked daytime ambulatory and evening home hypertension, especially in heavy smoking or older men.

2.
J Hazard Mater ; 384: 121359, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31635821

RESUMO

The bio-oxidative dissolution of arsenopyrite, the most severe arsenic contamination source, can be mediated by organic substances, but pertinent studies on this subject are scarce. In this study, the bio-oxidative dissolution of arsenopyrite by Sulfobacillus thermosulfidooxidans and arsenic immobilization were evaluated in the presence of humic acid (HA). The mineral dissolution was monitored through analyses of the parameters in solution, phase and element speciation transformations on the mineral surface, and arsenic immobilization on the surfaces of cells and jarosites-HA. The results show that the presence of HA enhances the dissolution of arsenopyrite, e.g., 7.1% of arsenopyrite was in the residue after 12 d of bio-oxidation compared to 19.3% in the absence of HA. Meanwhile, the presence of HA led to changes of the fates of As and Fe and no accumulation of elemental sulfur (S0) or ferric arsenate on the mineral surface. Moreover, a flocculent porous structure was formed on the surfaces of both microbial cells and jarosites, on which a large amount of arsenic was adsorbed. These results clearly indicate that HA can simultaneously promote the dissolution of arsenopyrite and arsenic immobilization, which may be significant for bioleaching of arsenopyrite-bearing contaminated sites.

3.
Plant Biotechnol J ; 18(2): 389-401, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31278885

RESUMO

Landraces often contain genetic diversity that has been lost in modern cultivars, including alleles that confer enhanced local adaptation. To comprehensively identify loci associated with adaptive traits in soya bean landraces, for example flowering time, a population of 1938 diverse landraces and 97 accessions of the wild progenitor of cultivated soya bean, Glycine soja was genotyped using tGBS® . Based on 99 085 high-quality SNPs, landraces were classified into three sub-populations which exhibit geographical genetic differentiation. Clustering was inferred from STRUCTURE, principal component analyses and neighbour-joining tree analyses. Using phenotypic data collected at two locations separated by 10 degrees of latitude, 17 trait-associated SNPs (TASs) for flowering time were identified, including a stable locus Chr12:5914898 and previously undetected candidate QTL/genes for flowering time in the vicinity of the previously cloned flowering genes, E1 and E2. Using passport data associated with the collection sites of the landraces, 27 SNPs associated with adaptation to three bioclimatic variables (temperature, daylength, and precipitation) were identified. A series of candidate flowering genes were detected within linkage disequilibrium (LD) blocks surrounding 12 bioclimatic TASs. Nine of these TASs exhibit significant differences in flowering time between alleles within one or more of the three individual sub-populations. Signals of selection during domestication and/or subsequent landrace diversification and adaptation were detected at 38 of the 44 flowering and bioclimatic TASs. Hence, this study lays the groundwork to begin breeding for novel environments predicted to arise following global climate change.

4.
Acta Trop ; 202: 105285, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31786108

RESUMO

Dipstick Dye Immunoassay (DDIA) and Indirect Haemagglutination Assay (IHA), are two commercially available kits which have been widely used for screening Schistosoma japonicum in P.R. China. Whether they can be used for screening of Schistosoma haematobium are not clear. In order to evaluate the diagnostic efficiency of DDIA and IHA for screening Schistosoma haematobium, serum samples were collected from pupils in endemic areas in Zambia, Southern Africa, and tested by DDIA and IHA by single-blind manner. Meanwhile, the pupils were microscopically examined by infection with Schistosoma and soil-transmitted helminths, visually observed for parasite eggs. Of the enrolled 148 pupils, 61% tested positive for S. haematobium infection, while 31% and 36% of pupils were infected with hookworm and Ascaris respectively. Regarding the parasitological tests as reference standard, for the diagnosis of S. haematobium infection, IHA performed higher sensitivity (74%, 95% CI: 65%-83%) than that of DDIA (60%, 95%CI: 49%-70%). The sensitivities of IHA and DDIA are significant higher in 10-14 years old students than those of 7-9 years old group. The specificity of DDIA and IHA were 61% (95%CI: 49%-74%) and 72% (95%CI: 60%-84%), respectively. The co-infection with STHs decreased the specificity of DDIA but had no impact on that of IHA. Our study indicated that IHA has more potential as an alternative diagnostic tool for identifying schistosomiasis haematobium but need further improvement.

5.
Emerg Infect Dis ; 26(1): 179-180, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31855529

RESUMO

China has made remarkable progress in reducing schistosomiasis caused by Schistosoma japonicum over the past 7 decades but now faces a severe threat from imported schistosomiasis. Results from national surveillance during 2010-2018 indicate integrating active surveillance into current surveillance models for imported cases is urgently needed to achieve schistosomiasis elimination in China.

6.
Mediators Inflamm ; 2019: 3738409, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31814800

RESUMO

Mechanical ventilation (MV) is a major life support technique for the management of trauma-associated hemorrhagic shock (HS). Ventilator-induced diaphragm dysfunction (VIDD), one of the most common complications of MV, has been well demonstrated in animal and human studies. However, few data are available concerning the effects of MV on diaphragm function in HS victims. In the present study, we found diaphragm muscle atrophy and weakness in HS but not in healthy animals after 4 hours of MV. The inhibition of autophagy resulted in reduced muscle fiber atrophy and improved forces. In addition, we observed diaphragmatic interleukin- (IL-) 6 overexpression and activation of its downstream signaling JAK/STAT in HS animals after MV, and either the neutralization of IL-6 or the inhibition of the JAK/STAT pathway attenuated autophagy, diaphragm atrophy, and weakness. Importantly, treatment with nonselective antioxidant exerted no protective effects against VIDD in HS animals. In addition, in vitro study showed that exogenous IL-6 was able to induce activation of JAK/STAT signaling and to increase autophagy in C2C12 cells. Moreover, the inhibition of JAK/STAT signaling abolished IL-6-induced cell autophagy. Together, our results suggested that HS sensitized the diaphragm to ventilator-induced atrophy and weakness through the activation of IL-6/JAK/STAT signaling-mediated autophagy in rats.

7.
Anal Chem ; 91(19): 12435-12443, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31453685

RESUMO

Efficient detection of aberrant glycoproteins in serum is particularly important for biomarker discovery. However, direct quantitation of glycoproteins in serum remains technically challenging because of the extraordinary complexity of the serum proteome. In the current work, we proposed a straightforward and highly efficient strategy by using the nonglycopeptides releasing from the specifically enriched glycoproteins for targeted glycoprotein quantification. With this so-called nonglycopeptide-based mass spectrometry (NGP-MS) strategy, a powerful and nondiscriminatory pipeline for hepatocellular carcinoma (HCC) glycoprotein biomarker discovery, verification, and validation has been developed. First, a data set of 234 NGPs was strictly established for multiple-reaction monitoring (MRM) quantification in serum. Second, the NGPs enriched from 20 HCC serum mixtures and 20 normal serum mixtures were labeled with mTRAQ reagents (Δ0 and Δ8, respectively) to find the differentially expressed glycoproteins in HCC. A total of 97 glycoprotein candidates were preliminarily screened and submitted for absolute quantitation with NGP-based stable-isotope-labeled (SID)-MRM in the individual samples of 38 HCC serum and 24 normal controls. Finally, 21 glycoproteins were absolutely quantified with high quality. The diagnostic sensitivity results showed that three glycoproteins, ß-2-glycoprotein 1 (APOH), α-1-acid glycoprotein 2 (ORM2), and complement C3 (C3), could be used for the discrimination between HCC patients and healthy people. A novel glycoprotein biomarker panel [APOH, ORM2, C3, and α-fetoprotein (AFP)] has proven to outperform AFP, the known HCC serum biomarker, alone, in this study. We believe that this strategy and the panel of glycoproteins might hold great clinical value for HCC detection in the future.

8.
Acta Trop ; 199: 105102, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31330123

RESUMO

The geographical distribution of snail (i.e., the intermediate host of schistosomiasis) is consistent with that of endemic areas. The suitable snail habitus requires necessary environmental conditions for snail population. The high-resolution remote sensing provides an important tool for the spatio-temporal analysis of disease monitoring and prediction. This study conducted a typical schistosomiasis epidemic area in the marshland and lake regions along the Yangtze River, Yueyang City, Hunan Province of China. And three types of environmental factors, i.e., NDVI, soil moisture, and shortest distance to water body, associated with the geographical distribution of snail population, were extracted from the high-resolution remoting sensing data. The predicted distribution of snail habitus from the high-resolution environmental factors were compared with the data of annual program of snail survey. The results have shown that the application of high-resolution remote sensing can improve the accuracy of the modeled and predicted the potential risk areas of schistosomiasis, and may become an important tool for the ongoing national schistosomiasis control program.


Assuntos
Tecnologia de Sensoriamento Remoto , Esquistossomose/transmissão , Caramujos , Animais , China/epidemiologia , Demografia , Humanos , Lagos , Esquistossomose/prevenção & controle , Análise Espaço-Temporal
9.
J Mol Model ; 25(8): 252, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31353431

RESUMO

The present study is aimed at probing the hydrogen bonding interaction between epinephrine and uracil by means of density functional theory calculations concerning their complexation's geometries, interaction energies, and vibrational frequencies. Geometry optimization was carried out giving 19 stable geometries of epinephrine-uracil complex with interaction energies in a range of - 21.51 to - 62.37 kJ mol-1 using the basis set superposition error (BSSE) correction. The analysis of structure and vibration shows that the hydrogen bonding elongates the length of corresponding bond O(N)-H and decreases the symmetric stretching vibrational frequency, which indicates red-shifted H-bonding interactions in all the geometries. Additionally, the analysis with theories of natural bond orbital (NBO), atoms in molecules (AIM), and the reduced density gradient (RDG) of hydrogen bonding properties and characteristics of the 19 geometries suggests that the hydrogen bonding in all the optimized structures of epinephrine-uracil complex is kind of a closed-shell interaction and mainly electrostatic dominant.


Assuntos
Epinefrina/química , Ligações de Hidrogênio , Uracila/química
10.
J Agric Food Chem ; 67(32): 8756-8765, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31310525

RESUMO

Parasitism usually causes considerable changes in lipids and fatty acids by redirecting the development of the host. In this study, changes in weight and in free fatty acid content of cotton aphids were recorded after aphids had been parasitized. Results showed that the weight of parasitized Aphis gossypii was increased compared to nonparasitized aphids, and significantly increased weights were detected at 1, 2, and 3 instars after parasitization by Lysiphlebia japonica. Free fatty acid test kits and GC-MS showed that the fatty acid content increased in the early stage of parasitization but decreased after 3 days of parasitization. Seven genes related to the fatty acid synthesis pathway were significantly upregulated in the parasitized aphids, where they were 1.96-10.97 times greater. Our data described the change that occurs in the fatty acid content of parasitized A. gossypii.


Assuntos
Afídeos/metabolismo , Ácidos Graxos/metabolismo , Vespas/fisiologia , Animais , Afídeos/química , Afídeos/parasitologia , Ácidos Graxos/química , Cromatografia Gasosa-Espectrometria de Massas , Interações Hospedeiro-Parasita
11.
Acta Trop ; 198: 105077, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31310730

RESUMO

The geographical distribution of snail (i.e., the intermediate host of schistosomiasis) is consistent with that of endemic areas. The suitable snail habitus requires necessary environmental conditions for snail population. The high-resolution remote sensing provides an important tool for the spatio-temporal analysis of disease monitoring and prediction. This study conducted a typical schistosomiasis epidemic area in the marshland and lake regions along the Yangtze River, Yueyang City, Hunan Province of China. And three types of environmental factors, i.e., NDVI, soil moisture, and shortest distance to water body, associated with the geographical distribution of snail population, were extracted from the high-resolution remoting sensing data. The predicted distribution of snail habitus from the high-resolution environmental factors were compared with the data of annual program of snail survey. The results have shown that the application of high-resolution remote sensing can improve the accuracy of the modeled and predicted the potential risk areas of schistosomiasis, and may become an important tool for the ongoing national schistosomiasis control program.


Assuntos
Lagos/parasitologia , Caramujos/parasitologia , Análise Espaço-Temporal , Água/parasitologia , Animais , China/epidemiologia , Demografia , Humanos , Tecnologia de Sensoriamento Remoto , Rios , Esquistossomose/epidemiologia , Caramujos/fisiologia , Solo
12.
Infect Dis Poverty ; 8(1): 48, 2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31208457

RESUMO

BACKGROUND: An "integrated control" strategy has been implemented within seven provinces at highest risk for schistosomiasis along Yangtze River in Peoples' Republic of China (P. R. China) since 2004. Since Oncomelania hupensis is the only intermediate host of the blood fluke (Schistosoma japonicum), controlling the distribution of snails is considered an essential and effective way to reduce the risk of schistosomiasis infection. The study aimed to determine the snail area burden and annual trend among provinces with potential risk for schistosomiasis along the Yangtze River, above and below the Three Gorges Dam (TGD). METHODS: This retrospective study utilized data previously collected from the National Parasitic Diseases Control Information Management System (NPDCIMS) on annual snail surveys from 2009 to 2017. Descriptive statistics were performed for analyzing the snail burden by provinces, counties, type of environmental location and year, and mapping was conducted to present the snails distribution. RESULTS: From 2009 to 2017, the total snail infested area decreased by 4.22%, from 372 253 hm2 to 356 553 hm2 within the seven high risk provinces. The majority of snails were found in the marshland and lake regions, outside of control embankments. The total snail burden trend remained relatively stable in upstream regions above the TGD from 2010 to 2015, while the trend decreased within downstream regions during this period. In 2016 and 2017, the total snail burden trend increased in both upstream and downstream provinces, however, upstream saw a larger increase. From 2009 to 2017, there were a total of 5990 hm2 of newly developed snail areas in the seven study provinces and the majority were concentrated in regions below the TGD, accounting for 5610 hm2 (93.70%). CONCLUSIONS: There has been a decline in total snail counts from 2009 to 2017. Meanwhile, new snail breeding areas were formed mainly within provinces downstream the TGD due to spread of snails, indicated that the oncomelanid snail would be difficult to completely eliminate. We suggest that the national schistosomiasis integrated control strategy, including mollusciding and environmental modification, will need to be enhanced significantly going forward to achieve a greater reduction in snail burden and ultimately to achieve elimination.


Assuntos
Schistosoma japonicum/isolamento & purificação , Caramujos/parasitologia , Distribuição Animal , Animais , China , Estudos Retrospectivos , Estações do Ano
13.
Acta Trop ; 195: 135-141, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31047863

RESUMO

World Bank Loan Project (WBLP) for schistosomiasis control conducted from 1992 to 2001, resulted in significant reduction of schistosomiasis morbidity and mortality in People's Republic of China (P.R. China), with implementation of morbidity control. Thereafter, an integrated control strategy, which targeted blocking disease transmission from reservoir hosts to the environment, was initiated in order to conquer schistosomiasis rebound after WBLP completion. Data obtained from the national schistosomiasis control reporting systems was collected and analyzed. The number of confirmed cases and infected cattle decreased significantly from 2002 to 2017, while no infected snails were found by dissection for four consecutive years. However, lake and marshland regions and some parts areas of Yunnan Province require attention for rigorous schistosomiasis control efforts. There is need to strengthen precise interventions and sensitive surveillance to achieve schistosomiasis elimination in P.R. China.


Assuntos
Bovinos/parasitologia , Controle de Doenças Transmissíveis/estatística & dados numéricos , Morbidade , Vigilância da População , Esquistossomose/mortalidade , Esquistossomose/prevenção & controle , Animais , China/epidemiologia , Humanos , Esquistossomose/epidemiologia
14.
Sci Total Environ ; 671: 208-214, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-30928750

RESUMO

In this study, bacterial mercury (Hg) methylation was investigated under the influence of red-tide algae of Skeletonema costatum (S. costatum). The distribution and speciation of total mercury (THg) and methylmercury (MeHg) were profiled by employing Geobacter metallireducens (G. metallireducens GS-15) as the methylating bacteria. G. metallireducens GS-15 showed different capabilities in methylating different inorganic forms of Hg(II) (HgCl2) and Hg(II)-Algae (HgCl2 captured by S. costatum) to MeHg. In the absence of S. costatum, a maximum methylation efficiency of 4.31 ±â€¯0.47% was achieved with Hg(II) of 1-100 µg L-1, while accelerated MeHg formation rate was detected at a higher initial Hg(II) concentration. In the presence of S. costatum, there were distinct changes in the distribution of THg and MeHg by altering the bioavailability of Hg(II) and Hg(II)-Algae. A larger proportion of THg tended to be retained by a higher algal biomass, resulting in decreased methylation efficiencies. The methylation efficiency of Hg(II) decreased from 3.01 ±â€¯0.10% to 1.01 ±â€¯0.01% with 10-mL and 250-mL algal media, and that of Hg(II)-Algae decreased from 0.83 ±â€¯0.13% to 0.22 ±â€¯0.01% with 10-mL and 250-mL Hg(II)-Algae media. Fourier transform infrared spectrometry, surface charge properties and elemental compositions of S. costatum were used to infer that amine, carboxyl and sulfonate functional groups were most likely to interact with Hg(II) through complexation and/or electrostatic attraction. These results suggest that red-tide algae may be an influencing factor on bacterial Hg methylation in eutrophic water bodies.


Assuntos
Diatomáceas/metabolismo , Geobacter/metabolismo , Mercúrio/metabolismo , Compostos de Metilmercúrio/metabolismo , Poluentes Químicos da Água/metabolismo , Metilação
15.
Biomed Pharmacother ; 113: 108655, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30849637

RESUMO

In this study, we aimed to explore the expression profiles of some known functional lncRNAs in esophageal adenocarcinoma (EAD) and to screening the potential prognostic makers, using data from The Cancer Genome Atlas (TCGA)-esophageal carcinoma (ESCA). Results showed that DLEU2 is a high potential OS related marker among 73 functional lncRNAs. DLEU2 and its intronic miR-15a and miR-16-1 expression were significantly upregulated in EAD compared with adjacent normal tissues. However, miR-15a and miR-16-1 expression were only weakly correlated with DLEU2 expression. Univariate and multivariate analysis confirmed that DLEU2 expression, but not miR-15a or miR-16-1 expression is an independent prognostic marker in terms of OS (HR:1.688, 95%CI: 1.085-2.627, p = 0.020) in EAD patients. The exon 9 of DLEU2 is very strongly co-expressed with DLEU2 (Pearson's r = 0.96) and showed better predictive value than total DLEU2 expression in predicting the OS of EAD patients. Multivariate analysis confirmed its independent prognostic value (HR:1.970, 95%CI: 1.266-3.067, p = 0.003), after adjustment of histologic grade, pathological stages and the presence of residual tumor. By checking the methylation status of DLEU2 gene, we excluded the possibility of the influence of two CpG sites near the DLEU2 exon 9 locus on its expression. In addition, although copy number alterations (CNAs) were observed DLEU2 gene, heterozygous loss (-1), low-level copy gain (+1) and high-level amplification (+2) had no significant association with DLEU2 transcription. Based on these findings, we infer that DLEU2 exon 9 expression might serve as a valuable biomarker of unfavorable OS in EAD patients.


Assuntos
Adenocarcinoma/metabolismo , Biomarcadores Tumorais/biossíntese , Neoplasias Esofágicas/metabolismo , Éxons/genética , RNA Longo não Codificante/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/mortalidade , Ilhas de CpG/genética , Epigênese Genética , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/mortalidade , Feminino , Humanos , Modelos Lineares , Masculino , Prognóstico , RNA Longo não Codificante/genética , Análise de Sobrevida , Proteínas Supressoras de Tumor/genética , Regulação para Cima
16.
Sci Total Environ ; 665: 810-819, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30790753

RESUMO

We used a hybrid precipitation method to simultaneously extract and analyze 24 personal care products (PCPs), including 16 biocides, 4 synthetic musks, and 4 benzotriazoles, in the plasma of fish. The method's performance was validated for plasma samples with and without ß-glucuronidase/aryl-sulfatase hydrolysis. The recoveries were in the range of 70-120% for most of the PCPs, except N,N-diethyl-3-methylbenzamide (DEET), clotrimazole (CTZ), miconazole and itraconazole at spiking concentration of 20 and 5 ng/mL. The quantification limits ranged between 0.89 and 17.9 ng/mL (hydrolyzed plasma) and 0.85-18.5 ng/mL (non-hydrolyzed plasma), except CTZ at 77.5 ng/mL and 76.3 ng/mL. Totally, 13 PCPs were detected in plasma samples of fish collected from the Yangtze River, with a maximum concentration of 58.4 ng/mL (galaxolide). Compounds with the phenol hydroxyl groups of parabens or triclosan in hydrolyzed plasma showed higher concentrations than those in unhydrolyzed plasma with the ratio of conjugation (glucuronides + sulfates) forms up to 86%. The median values for the logarithm of bioaccumulation factors were between 1.39 and 4.15, which were 2-3 orders of magnitude higher than the theoretical logarithm of bioconcentration factors. Using the fish plasma model, the effect ratios (effect concentration/measured plasma concentration ratios) of tonalide, galaxolide, benzotriazole, triclosan, and DEET reached 0.35, 4.15, 3.78, 7.52, and 9.24, respectively. These are recognized as priority chemicals for further risk assessment.


Assuntos
Cosméticos/metabolismo , Desinfetantes/metabolismo , Exposição Ambiental , Monitoramento Ambiental/métodos , Peixes/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , China , Rios
17.
PLoS One ; 14(2): e0212965, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30807599

RESUMO

We investigated the molecular characteristics and antimicrobial susceptibility of Clostridium difficile isolated from animals in China. We obtained 538 rectal swabs from pigs, chickens and ducks in 5 provinces during 2015 and 2016. C. difficile isolates were characterized by detection of toxin genes, multilocus sequence typing and ribotyping. And antimicrobial susceptibility testing was performed using the agar dilution method. Out of 538 samples, 44 (8.2%) were C. difficile positive with high prevalence in pigs (n = 31). Among these, 39 (88.6%) were toxigenic including 14 (31.8%) that were A+B+CDT+ and 13 (29.5%) A+B+. The remaining 12 (27.3%) were A-B+. We identified 7 ST types and 6 PCR ribotypes. The most predominant type was ST11/RT078 with toxin profile A+B+CDT+ and all were isolated from piglets with diarrhea. ST109 isolates possessed two different toxigenic profiles (A-B-CDT- and A-B+CDT-) and although it was not the most prevalent sequence type, but it was widely distributed between chickens, ducks and pigs in the 5 provinces. All C. difficile isolates were fully susceptible to vancomycin, metronidazole, fidaxomicin, amoxicillin/clavulanate and meropenem but retained resistance to 4 or 5 of the remaining antibiotics, especially cefotaxime, tetracycline, ciprofloxacin, cefoxitin. The RT078/ST11 isolates were simultaneously resistant to cefotaxime, tetracycline, cefoxitin, ciprofloxacin and imipenem. This is the first report of the molecular epidemiology of C. difficile isolated from food animals in China. We identified the epidemic strain RT078/ST11 as the predominate isolate among the animals we screened in our study.


Assuntos
Clostridium difficile/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Cefotaxima/análise , Cefoxitina/farmacologia , Galinhas , China , Ciprofloxacino/farmacologia , Clostridium difficile/genética , Clostridium difficile/isolamento & purificação , Patos , Imipenem/farmacologia , Metronidazol/farmacologia , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Reação em Cadeia da Polimerase , Ribotipagem , Suínos , Tetraciclina/farmacologia , Vancomicina/farmacologia
18.
Chin Med J (Engl) ; 132(4): 446-453, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30707165

RESUMO

BACKGROUND: Adhesion, biofilm formation, yeast-hyphal transition, secretion of enzymes, and hemolytic activity are all considered important factors in Candida tropicalis infection. However, DNA sequence data for this pathogen are limited. In this study, the polymorphism and heterogeneity of genes agglutinin-like sequences (ALS)2, Lipase (LIP)1, LIP4, and secretory aspartyl proteinase tropicalis (SAPT)1-4 as well as the relationship between phenotype and genotype were analyzed. METHODS: This study started in August 2013, and ended in July 2017. The complete length of ALS2, LIP1, LIP4, and SAPT1-4 of 68 clinical C. tropicalis isolates was sequenced. Single nucleotide polymorphisms (SNPs) as well as insertions and deletions (indels) were identified within these genes. In addition, phenotypic characteristics of the virulent factors, including adhesion and the secretion of aspartyl proteinases and phospholipases, were determined. RESULTS: There were 73, 24, 17, 16, 13, and 180 SNPs in the genes LIP1, LIP4, SAPT1, SAPT2, SAPT3, and SAPT4, respectively. Furthermore, 209 SNPs were identified in total for the gene ALS2. Interestingly, large fragment deletions and insertions were also found in ALS2. Isolate FXCT 01 obtained from blood had deletions on all 4 sites and showed the lowest adhesion ability on the polymethylpentene surface. In addition, isolates with deletions in the regions 1697 to 1925 and 2073 to 2272 bp displayed relatively low abilities for adhesion and biofilm formation, and this phenotype correlated with the deletions found in ALS2. LIP1, SAPT4, and ALS2 displayed great heterogeneity among the isolates. Large deletions found in gene ALS2 appeared to be associated with the low ability of adhesion and biofilm formation of C. tropicalis. CONCLUSION: This study might be useful for deeper explorations of gene function and studying the virulent mechanisms of C. tropicalis.


Assuntos
Candida tropicalis/genética , Polimorfismo de Nucleotídeo Único , Aderência Bacteriana , Biofilmes , Candida tropicalis/patogenicidade , Lipase/genética , Virulência/genética
19.
Environ Geochem Health ; 41(1): 297-308, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29948539

RESUMO

Using sodium alginate hydrogel as skeleton, in combination with chitosan and magnetic Fe3O4, a new type of magnetic chitosan/sodium alginate gel bead (MCSB) was prepared. Adsorptive removal of Cu(II) from aqueous solutions was studied by using the MCSB as a promising candidate in environmental application. Different kinetics and isotherm models were employed to investigate the adsorption process. Based on Fourier transform infrared spectroscopy, field-emission scanning electron microscope, CHNS/O elements analysis, vibration magnetometer, and various means of characterization, a comprehensive analysis of the adsorption mechanism was conducted. The MCSB had a good magnetic performance with a saturation magnetization of 12.5 emu/g. Elemental analysis proved that the addition of chitosan introduced a considerable amount of nitrogen-rich groups, contributing significantly to copper adsorption onto gel beads. The contact time necessary for adsorption was optimized at 120 min to achieve equilibrium. Experimental data showed that the adsorption process agreed well with the Langmuir isotherm model and the pseudo-second-order kinetics model. The theoretical maximum adsorption capacity of MCSB for Cu(II) could reach as high as 124.53 mg/g. In conclusion, the MCSB in this study is a novel and promising composite adsorbent, which can be applied for practical applications in due course.


Assuntos
Alginatos/química , Quitosana/química , Cobre/isolamento & purificação , Nanosferas/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/ultraestrutura , Nanosferas/ultraestrutura , Termodinâmica
20.
Chemosphere ; 216: 179-185, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30368082

RESUMO

Algae and mercury (Hg) are ubiquitous in marine environments. In this study, we investigated the effects of a typical marine algae of diatom Skeletonema costatum on Hg methylation by an iron-reducing bacterium of Geobacter sulfurreducens (G. sulfurreducens) PCA. In the absence of Skeletonema costatum, the bacterial MeHg production rate maximized at 104.06 ±â€¯11.7 ng L-1 h-1 with a high Hg level, while the highest methylation efficiency was achieved at a low Hg concentration. The existence of Skeletonema costatum greatly inhibited the capability of G. sulfurreducens PCA to methylate Hg. With the increase in algal biomass, there was a significant mitigation of MeHg formation and Hg0 release, leaving a considerable proportion of immobilized Hg2+ species (up to 47%) associated with algal cell materials. These results suggest that marine algae are crucial in determining the bioavailability of Hg contaminants and the methylating potential of G. sulfurreducens PCA.


Assuntos
Diatomáceas/patogenicidade , Geobacter/metabolismo , Mercúrio/metabolismo , Compostos de Metilmercúrio/metabolismo , Disponibilidade Biológica , Biomassa , Cianobactérias/metabolismo , Metilação
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