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1.
Arch Virol ; 167(5): 1343-1347, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35304673

RESUMO

The plant-pathogenic fungus Exobasidium gracile belongs to the basidiomycetous genus Exobasidium and causes leaf abnormalities in Camellia oleifera. Here, we report a novel mycovirus from E. gracile strain Z-2, called "Exobasidium gracile zybavirus 2" (EgZV2), which is related phylogenetically to a member of the genus Zybavirus in the family Amalgaviridae. Like those of other zybaviruses, the EgZV2 genome has two large open reading frames (ORFs) encoding an unknown protein and an RNA-dependent RNA polymerase (RdRp), respectively. In addition, we found a conserved +1 programmed ribosomal frameshifting (PRF) motif (UUUCGG) between ORF1 and ORF2 in EgZV2.


Assuntos
Micovírus , Vírus de RNA , Basidiomycota , Micovírus/genética , Fungos , Genoma Viral , Fases de Leitura Aberta , Filogenia , Plantas , Vírus de RNA/genética , RNA Viral/genética
2.
J Med Syst ; 44(10): 184, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32894360

RESUMO

Bone marrow smear examination is an indispensable diagnostic tool in the evaluation of hematological diseases, but the process of manual differential count is labor extensive. In this study, we developed an automatic system with integrated scanning hardware and machine learning-based software to perform differential cell count on bone marrow smears to assist diagnosis. The initial development of the artificial neural network was based on 3000 marrow smear samples retrospectively archived from Sir Run Run Shaw Hospital affiliated to Zhejiang University School of Medicine between June 2016 and December 2018. The preliminary field validating test of the system was based on 124 marrow smears newly collected from the Second Affiliated Hospital of Harbin Medical University between April 2019 and November 2019. The study was performed in parallel of machine automatic recognition with conventional manual differential count by pathologists using the microscope. We selected representative 600,000 marrow cell images as training set of the algorithm, followed by random captured 30,867 cell images for validation. In validation, the overall accuracy of automatic cell classification was 90.1% (95% CI, 89.8-90.5%). In a preliminary field validating test, the reliability coefficient (ICC) of cell series proportion between the two analysis methods were high (ICC ≥ 0.883, P < 0.0001) and the results by the two analysis methods were consistent for granulocytes and erythrocytes. The system was effective in cell classification and differential cell count on marrow smears. It provides a useful digital tool in the screening and evaluation of various hematological disorders.


Assuntos
Algoritmos , Medula Óssea , Humanos , Projetos Piloto , Reprodutibilidade dos Testes , Estudos Retrospectivos
3.
Bull Environ Contam Toxicol ; 103(5): 651-656, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31583422

RESUMO

Environmental DNA (eDNA), as a recent research hotspot in environmental science, the use of eDNA in biological monitoring has the advantages of sensitivity and time/labor saving. The eDNA technology combined with scientific advancement has been applied in investigations of target species (such as invasive species, endangered species and other rare species), biomass, and biodiversity. In addition, ecotoxicology studies and environmental pollution impact assessments based on the development of eDNA technology have gradually emerged in recent years. In this article, we summarizes the application of eDNA in ecological assessment, include species diversity assessment and chemical contamination impacts assessment, provide guiding questions for study design. We additionally discuss current challenges associated with eDNA. Finally, looking to the future, we discuss the opportunities of eDNA technology in environmental protein, environmental sample processor and ecogenomic sensors.


Assuntos
Biodiversidade , DNA Ambiental/análise , Monitoramento Ambiental/métodos , Animais , Biomassa , Espécies em Perigo de Extinção , Espécies Introduzidas
4.
Cell Physiol Biochem ; 45(3): 917-934, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29428961

RESUMO

BACKGROUND/AIMS: Triptolide (TP) is a diterpenoid triepoxide extracted from the traditional Chinese medical herb Tripterygium wilfordii that exerts prominent broad-spectrum anticancer activity to repress proliferation and induce cancer cell apoptosis through various molecular pathways. We previously observed that TP inhibits the progression of A549 cells and pancreatic cancer cells (PNCA-1) in vitro. However, the complex molecular mechanism underlying the anticancer activity of TP is not well understood. METHODS: To explore the molecular mechanisms by which TP induces lung cancer cell apoptosis, we investigated changes in the protein profile of A549 cells treated with TP using a proteomics approach (iTRAQ [isobaric tags for relative and absolute quantitation] combined with NanoLC-MS/MS [nano liquid chromatography-mass spectrometry]). Changes in the profiles of the expressed proteins were analyzed using the bioinformatics tools OmicsBean and the Kyoto Encyclopedia of Genes and Genomes (KEGG) and were verified using western blotting. Apoptosis and cell cycle effects were analyzed using flow cytometry. RESULTS: TP induced apoptosis in A549 cells and blocked A549 cells at the G2/M phase. Using iTRAQ technology, we observed 312 differentially expressed proteins associated in networks and implicated in different KEGG pathways. Gene Ontology (GO) analysis showed the overviews of dysregulated proteins in the biological process (BP), cell component (CC), and molecular function (MF) categories. Moreover, some candidate proteins involved in PARP1/AIF and nuclear Akt signaling pathways or metastasis processes were validated by western blotting. CONCLUSION: TP exerted anti-tumor activity on non-small cell lung cancer (NSCLC) A549 lung adenocarcinoma cells by dysregulating tumor-related protein expression. Herein, we provide a preliminary study of TP-related cytotoxicity on A549 cells using proteomics tools. These findings may improve the current understanding of the anti-tumor effects of TP on lung cancer cells and may reveal candidate proteins as potential targets for the treatment of lung cancer.


Assuntos
Diterpenos/farmacologia , Fenantrenos/farmacologia , Proteoma/efeitos dos fármacos , Proteômica , Células A549 , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Apoptose/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Diterpenos/química , Medicamentos de Ervas Chinesas/farmacologia , Compostos de Epóxi/química , Compostos de Epóxi/farmacologia , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Nanotecnologia , Fenantrenos/química , Poli(ADP-Ribose) Polimerase-1/metabolismo , Mapas de Interação de Proteínas/efeitos dos fármacos , Proteoma/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Espectrometria de Massas em Tandem , Tripterygium/química , Tripterygium/metabolismo
5.
Ecotoxicol Environ Saf ; 139: 43-49, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28109902

RESUMO

Hexabromocyclododecane (HBCD) is a brominated flame retardant used throughout the world. It has been detected in various environmental media and has been shown toxic to aquatic life. The toxic effects of HBCD to aquatic organisms in Chinese freshwater ecosystems are discussed here. Experiments were conducted with nine types of acute toxicity testing and three types of chronic toxicity testing. After comparing a range of species sensitivity distribution models, the optimal model of Bull III was used to derive the safety thresholds for HBCD. The acute safety threshold and the chronic safety threshold of HBCD for Chinese freshwater organisms were found to be 2.32mg/L and 0.128mg/L, respectively. Both values were verified by the methods of the Netherlands and the United States. HBCD was found to be less toxic compared to other widely used brominated flame retardants. The present results provide valuable information for revision of the water quality standard of HBCD in China.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Ecossistema , Exposição Ambiental/efeitos adversos , Retardadores de Chama/toxicidade , Água Doce/química , Hidrocarbonetos Bromados/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Bovinos , China , Exposição Ambiental/análise , Masculino , Testes de Toxicidade Aguda/métodos
6.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 45(4): 371-378, 2016 05 25.
Artigo em Zh | MEDLINE | ID: mdl-27868410

RESUMO

Objective: To detect the expression of miR-221/222 in serum and plasma cells in patients with monoclonal gammopathy of undetermined significance(MGUS) and multiple myeloma(MM), and to explore the possibility of miR-221/222 as biomarkers in the diagnosis and prognosis predicting of MGUS and MM. Methods: Bone marrow and serum samples from 14 patients with newly diagnosed MGUS, 81 patients with newly diagnosed or relapsed MM and 10 controls were collected from Sir Run Run Shaw Hospital of Zhejiang University and Tongde Hospital of Zhejiang Province during January 2013 and December 2015. The expressions of miR-221/222 in serum and in sorted CD138 positive plasma cells were detected by qRT-PCR, and the relative expression of miR-221/222 (Δct) was compared between the groups. Serum levels of miR-221 before and after treatment were compared in both remission group (n=22) and refractory group (n=13) in MM patients, and its correlation with serum level of ß2-MG was assessed using Pearson's correlation analysis. Results: Serum levels of miR-221/222 in MGUS and MM groups were significantly higher than those in control group (all P<0.01), while miR-221/222 levels in plasma cells were significantly lower in MGUS and MM groups than those in the control group (P<0.05 or<0.01). No significant difference in miR-221/222 levels in serum and plasma cells was observed between MGUS group and MM group (all P>0.05). There was no correlation between miR-221/222 levels in serum and plasma cells (r=0.024 and -0.127, all P>0.05), but miR-221 levels were correlated with miR-222 levels in both serum and plasma cells (r=0.534 and 0.552, all P<0.01). Receiver operating characteristic (ROC) curves showed that the areas under the curve (AUCs) of serum miR-221/222, plasma cell miR-221/222 in diagnosis of MGUS/MM were 0.968, 0.976, 0.801 and 0.727, respectively. There was no significant difference in serum level of miR-221 among MM patients with different paraprotein isotypes (P>0.05), but serum level of miR-221 in patients with relapsed MM was higher than that in patients with newly diagnosed MM (P<0.01). Compared with the patients with MGUS or MM stageⅠ and Ⅱ, patients with MM stage Ⅲ were of higher serum levels of miR-221 (P<0.01). Serum level of miR-221 decreased after chemotherapy in the remission group (U=51.5, P<0.01), but such decrease was not observed in the refractory group (U=67.5, P>0.05). Serum level of ß2-MG was positively correlated with serum level of miR-221 (r=0.524, P<0.01). Conclusion: miR-221/222 in serum and plasma cells may be biomarkers for early diagnosis of MGUS, and are helpful for diagnosis and efficacy evaluation of MM.


Assuntos
Biomarcadores/análise , Biomarcadores/sangue , Medula Óssea/química , MicroRNAs/análise , MicroRNAs/sangue , Mieloma Múltiplo/química , Proteínas do Mieloma/análise , Progressão da Doença , Humanos , Gamopatia Monoclonal de Significância Indeterminada/genética , Gamopatia Monoclonal de Significância Indeterminada/fisiopatologia , Mieloma Múltiplo/genética , Mieloma Múltiplo/fisiopatologia , Paraproteinemias/genética , Paraproteinemias/fisiopatologia , Prognóstico , Recidiva
7.
Environ Toxicol ; 30(9): 1014-23, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24596333

RESUMO

Tetrabromobisphenol A (TBBPA), a brominated flame retardant, is detected commonly in aquatic environments, where it is thought to be highly toxic to the development of aquatic life. In this study, zebrafish embryos and larvae were used to investigate the protective effects of puerarin after exposure to TBBPA. Malformation, blood flow disorders, pericardial edema, and spawn coagulation rates increased, whereas survival decreased significantly after exposure to 0.5 and 1.0 mg L(-1) TBBPA. The measured indices of morphological toxicity improved after treatment with puerarin. TBBPA also induced reactive oxygen species (ROS) production in a dose-dependent manner. Acridine orange staining results revealed that TBBPA exposure caused cardiomyocyte apoptosis and induced the expression of three proapoptotic genes: P53, Bax, and Caspase9. In contrast, the expression of the antiapoptotic gene Bcl2 was down-regulated. When genes related to cardiac development were assessed, the expression of Tbx1, Raldh2, and Bmp2b changed after exposure to the combination of TBBPA and puerarin. These results suggest that TBBPA induces cardiomyocyte apoptosis and ROS production, resulting in cardiac developmental toxicity in zebrafish embryos or larvae. Therefore, puerarin regulates the expression of cardiac developmental genes, such as Tbx1, Bmp2b, and Raldh2 by inhibiting ROS production, and subsequently modulates cardiac development after the exposure of zebrafish larvae to TBBPA.


Assuntos
Apoptose/efeitos dos fármacos , Isoflavonas/farmacologia , Bifenil Polibromatos/toxicidade , Substâncias Protetoras/farmacologia , Animais , Proteína Morfogenética Óssea 2/metabolismo , Caspase 9/metabolismo , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Retardadores de Chama/toxicidade , Larva/efeitos dos fármacos , Larva/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Retinal Desidrogenase/metabolismo , Proteínas com Domínio T/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Proteína X Associada a bcl-2/metabolismo
8.
Ecol Evol ; 14(2): e10849, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38384828

RESUMO

Environmental stressors and disturbances can cause changes in an ecosystem's community structure, which can be reflected in its functional diversity. As grazing intensity increases, this causes changes in the environment that inevitably lead to changes in the community structure, which can especially affect rodents due to their sensitivity to the environment. The effects of grazing prohibition and overgrazing on the functional diversity of desert rodent communities in Alxa were studied in April, July, and October of 2018-2020. The trap-day method was used to study rodent communities in disturbed habitats. Five functional traits were selected and quantified: nutrition, life history, physiology, morphology, and activity rhythm. The results showed that: (1) The species composition of rodent communities in the Alxa Desert in spring and autumn was significantly correlated with the functional traits of the hibernation, reproductive cycle, and feeding habits. The species composition in the summer was only significantly correlated with the functional traits of reproductive cycle and diet. (2) The effects of overgrazing on the functional diversity of rodents in desert areas have significant temporal and spatial characteristics. (3) In spring and summer, overgrazing made the Functional Richness index of the rodent community lower than that of areas where grazing is prohibited, but the Functional Evenness index was higher than that of grazing-prohibition areas. In autumn, overgrazing increased the Functional Richness index of the rodent community and decreased the Functional Evenness index. The Functional Divergence index was higher in overgrazing areas than in grazing-prohibited ones. These results suggest that, in spring and summer, overgrazing reduced the ecological space utilization ability of rodent communities; however, the impact on the degree of utilization of community resources is more comprehensive. In autumn, overgrazing increases the ability of rodent communities to use ecological space but reduces resource efficiency. Overgrazing makes the niche differentiation of rodent communities higher, the degree of overlap lower, and the competition between species weaker. Therefore, overgrazing will affect the functional diversity of the community through the utilization of ecological space, resource utilization, interspecific competition, and niche.

9.
Int J Biol Macromol ; 261(Pt 1): 129673, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38281528

RESUMO

Poly(lactic acid) (PLA) composites reinforced with cellulose nanocrystals (CNCs) are promising biodegradable materials. However, the poor compatibility and dispersion of CNCs in the PLA matrix remain a significant obstacle to improving the properties of composites. In this study, the modified CNC (CNC-D) was prepared through sulfonation treatment, followed by modification with didecyl dimethyl ammonium chloride (DDAC). Then, CNC-D was mixed with PLA to prepare composite films (PLA-CNC-D). The results revealed that the PLA-CNC-D had higher tensile strength and elongation at break than PLA-CNC at 3 wt% nanofiller content, increasing by 41.53 and 22.18 %, respectively. SEM and DSC analysis indicated that surface modification improved the compatibility and dispersion of CNC-D in the PLA matrix. The sulfonation process increased the anion content on the surface of CNC-D, enabling the CNC-D surface to adsorb more cationic DDAC, consequently sharply reducing the hydrophilicity of CNC-D. Moreover, the PLA-CNC-D exhibited excellent antibacterial activity against S. aureus and E. coli. In summary, this study provides a novel CNC modification approach to enhance the physical properties and antibacterial activity of PLA composite films, enlarging the application of degradable PLA composites.


Assuntos
Compostos de Amônio , Nanopartículas , Compostos de Amônio Quaternário , Celulose/química , Polímeros/química , Escherichia coli , Staphylococcus aureus , Poliésteres/química , Nanopartículas/química , Antibacterianos/farmacologia
10.
Ecol Evol ; 14(3): e11056, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38435014

RESUMO

Soil fungi are involved in the decomposition of organic matter, and they alter soil structure and physicochemical properties and drive the material cycle and energy flow in terrestrial ecosystems. Fungal community assembly processes were dissimilar in different soil layers and significantly affected soil microbial community function and plant growth. Grazing exclusion is one of the most common measures used to restore degraded grasslands worldwide. However, changes in soil fungal community characteristics during grazing exclusion in different types of grasslands are unknown. Here, we investigated the effects of a 9-year grazing exclusion on soil properties, fungal community composition, and diversity in three grassland types (temperate desert, temperate steppe, and mountain meadow). The results showed that (1) in the 0-5 cm soil layer, grazing exclusion significantly increased the differences in SWC, SOC, KN, and N:P among the three grassland types, while the final pH, BD, TP, C:N, and C:P values were consistent with the results before exclusion. In the 5-10 cm soil layer, grazing exclusion significantly increased total phosphorus (TP) in temperate deserts by 34.1%, while significantly decreasing bulk density (BD) by 9.8% and the nitrogen: phosphorus ratio (N:P) by 47.1%. (2) The soil fungal community composition differed among the grassland types, For example, significant differences were found among the three grassland types for the Glomeromycota and Mucoromycota. (3) Under the influence of both grazing exclusion and grassland type, there was no significant change in soil fungal alpha diversity, but there were significant differences in fungal beta diversity. (4) Grassland type was the most important factor influencing changes in fungal community diversity, and vegetation cover and soil kjeldahl nitrogen were the main factors influencing fungal diversity. Our research provides a long-term perspective for better understanding and managing different grasslands, as well as a better scientific basis for future research on grass-soil-microbe interactions.

11.
Environ Health Prev Med ; 18(1): 33-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22752656

RESUMO

OBJECTIVES: The aim of this chronological study was to elucidate the effects of socio-economic status (SES) and physical health on the long-term care (LTC) needs of a Japanese elderly population and to explore their causal relationships. METHODS: A self-administered questionnaire was distributed to all residents aged 65 years and older of Tama City, Tokyo, in September 2001. A total of 13,195 completed questionnaires were returned, giving a response rate of 80.2 %. A follow-up study was done using the same questionnaire in 2004. Ultimately, 7,905 respondents were included in our analysis. Data analysis was performed using correlation analysis and structural equation modeling (SEM). For SEM, we used one observed variable (LTC needs in 2004) and three latent variables (SES in 2001 and physical health in both 2001 and 2004). RESULTS: The data were well fit by the models, with a NFI of 0.980, CFI of 0.982, and RMSEA of 0.032. LTC needs were well explained by the three latent variables (R (2) = 0.70 and 0.66 for elderly men and women, respectively). Among all variables, physical health in 2004 was the strongest determinant of LTC needs, followed by physical health in 2001, and SES in 2001. Gender differences in the structural relationships were minor. CONCLUSIONS: Our results indicate that good physical health directly contributes to reducing LTC needs among Japanese elderly. In addition, efforts to increase income and educational levels may help to decrease LTC needs by indirectly improving physical health.


Assuntos
Necessidades e Demandas de Serviços de Saúde , Nível de Saúde , Assistência de Longa Duração , Classe Social , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Assistência de Longa Duração/estatística & dados numéricos , Masculino , Tóquio
12.
Technol Cancer Res Treat ; 22: 15330338221150069, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36700246

RESUMO

The evaluation of megakaryocytes is an important part of the work up on bone marrow smear examination. It has significance in the differential diagnosis, therapeutic efficacy assessment, and predication of prognosis of many hematologic diseases. The process of manual identification of megakaryocytes are tedious and lack of reproducibility; therefore, a reliable method of automated megakaryocytic identification is urgently needed. Three hundred and thirty-three bone marrow aspirate smears were digitized by Morphogo system. Pathologists annotated megakaryocytes on the digital images of marrow smears are applied to construct a large dataset for testing the system's predictive performance. Subsequently, we obtained megakaryocyte count and classification for each sample by different methods (system-automated analysis, system-assisted analysis, and microscopic examination) to study the correlation between different counting and classification methods. Morphogo system localized cells likely to be megakaryocytes on digital smears, which were later annotated by pathologists and the system, respectively. The system showed outstanding performance in identifying megakaryocytes in bone marrow smears with high sensitivity (96.57%) and specificity (89.71%). The overall correlation between the different methods was confirmed the high consistency (r ≥ 0.7218, R2 ≥ 0.5211) with microscopic examination in classifying megakaryocytes. Morphogo system was proved as a reliable screen tool for analyzing megakaryocytes. The application of Morphogo system shows promises to advance the automation and standardization of bone marrow smear examination.


Assuntos
Medula Óssea , Megacariócitos , Humanos , Reprodutibilidade dos Testes , Redes Neurais de Computação , Células da Medula Óssea
13.
J Environ Manage ; 113: 355-60, 2012 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-23102643

RESUMO

Organic matter and submerged plants may affect internal phosphate loading in lake sediment. In this study, we investigated the changes of alkaline phosphatase activity (APA) and phosphorus (P) fractions in lake sediment by adding organic matter (0.0%, 0.5% and 1.0% of dry weight) and plant submerged plants under experimental conditions. Results indicated that the APA in sediments significant increased after 50 days incubation than at 7 days. The APA in the treatments by adding organic matter and submerged plants increased by 26.37%-61.78% than that of control after 7 days incubation, and increased by 1.00%-29.51% at 50 days, indicating both organic matter and submerged plants may remarkable affect APA in sediment, especially for the early stage of incubation. In addition, the soluble reactive P (SRP) concentrations of the overlying water increased significantly with increasing sediment organic matter, possibly related to increase of APA in sediment. However, the release of SRP was obvious restrained due to absorption of submerged plant. TP and P fraction in sediment decreased with increasing incubation time, but the decrease of TP content in sediment was mainly from NaOH-P and OP sources, but not from HCl-P and IP. Effects of organic matter and submerged plants on P fractions in sediment mainly occurred in NaOH-P and OP fractions. At the end of experiments, the contents of NaOH-P and OP in the treatments by adding organic matter and submerged plant decreased by 5.46%-20.47% and 7.87%-21.46%, respectively. These results indicated that the relative importance of organic matter and submerged plants during the release and transformation of P in lake sediment.


Assuntos
Fosfatase Alcalina/metabolismo , Sedimentos Geológicos/química , Lagos/química , Compostos Orgânicos/química , Fósforo/química , Monitoramento Ambiental
14.
Infect Drug Resist ; 15: 7189-7206, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36514797

RESUMO

Purpose: Methicillin-resistant Staphylococcus aureus (MRSA) is one of the most common pathogens of community- and hospital-acquired infections, and its prevalence is increasing globally. Guiyang is the capital city of Guizhou Province, Southwest China; as the transport and tourism centre of Southwest China, Guizhou Province is bordered by Yunnan, Sichuan, Chongqing, and Guangxi Provinces. Although MRSA prevalence is increasing, little is known about its aspects in the area. The purpose of this study was to analyse MRSA molecular characteristics, antimicrobial resistance, and virulence genes in Guiyang. Methods: In total, 209 MRSA isolates from four hospitals (2019-2020) were collected and analysed by antimicrobial susceptibility testing and molecular classification by the MLST, spa, and SCCmec typing methods. Isolate antibiotic resistance rates were detected by a drug susceptibility assays. PCR amplification was used to detect the virulence gene-carrying status. Results: Twenty-four STs, including 4 new STs (ST7346, ST7347, ST7348, and ST7247) and 3 new allelic mutations, were identified based on MLST. The major prevalent ST type and clone complex were ST59 (49.8%) and CC59 (62.7%), respectively. Spa type t437 (42.1%) and SCCmec IV (55.5%) were identified by spa and SCCmec typing methods as the most important types. Drug sensitivity data showed that the multidrug resistance rate was 79.0%. There were significant differences in multidrug resistance rates and virulence gene-carrying rates for seb, hla, hlb, cna and bap between ST59 and non-ST59 types. Conclusion: ST59-SCCmecIV-t437 is a major epidemic clone in Guiyang that should be monitored by local medical and health institutions. The situation differs from other adjacent or middle provinces of China, which may be due to the special geographical location of the region and the trend in antibiotic use or lifestyle. This study provides empirical evidence for local medical and health departments to prevent and control the spread of MRSA.

15.
Int J Biol Macromol ; 209(Pt A): 299-314, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35381282

RESUMO

Antibiotic-resistant bacteria (including MRSA) in the clinic pose a growing threat to public health, and antimicrobial peptides (AMPs) have great potential as efficient treatment alternatives. Houseflies have evolved over long periods in complex, dirty environments, developing a special immune system to overcome challenges in harmful environments. AMPs are key innate immune molecules. Herein, two differentially expressed AMPs, Phormicins A and B, were identified by screening transcriptomic changes in response to microbial stimulation. Structural mimic assays indicated that these AMPs exhibited functional divergence due to their C-terminal features. Expression analysis showed that they had different expression patterns. Phormicin B had higher constitutive expression than Phormicin A. However, Phormicin B was sharply downregulated, whereas Phormicin A was highly upregulated, after microbial stimulation. The MIC, MBC and time-growth curves showed the antibacterial spectrum of these peptides. Crystal violet staining and SEM showed that Phormicin D inhibited MRSA biofilm formation. TEM suggested that Phormicin D disrupted the MRSA cell membrane. Furthermore, Phormicin D inhibited biofilm formation by downregulating the expression of biofilm-related genes, including altE and embp. Therefore, housefly Phormicins were functionally characterized as having differential expression patterns and antibacterial & antibiofilm activities. This study provides a new potential peptide for clinical MRSA therapy.


Assuntos
Moscas Domésticas , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Peptídeos Antimicrobianos , Biofilmes , Moscas Domésticas/genética , Testes de Sensibilidade Microbiana
16.
PeerJ ; 9: e10996, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33854836

RESUMO

Rodents exhibit seasonal changes in their activity patterns as an essential survival strategy. We studied the activity patterns and strategies of the Siberian jerboa (Orientallactaga sibirica) in the Alxa desert region to better understand the habitats and behavioural ecology of xeric rodents. We conducted an experiment using three plots to monitor the duration, time, and frequency of the active period of the Siberian jerboa using infrared cameras in the Alxa field workstation, Inner Mongolia, China in 2017. The relationships between the activity time and frequency, biological factors (perceived predation risk, food resources, and species composition), and abiotic factors (temperature, air moisture, wind speed) were analysed using Redundancy Analysis (RDA). Our results showed that: (1) relative humidity mainly affected activities in the springtime; temperature, relative humidity and interspecific competition mainly affected activities in the summertime; relative humidity and perceived predation risk mainly influenced activities in the autumn. (2) The activity pattern of the Siberian jerboa altered depending on the season. The activity of the Siberian jerboa was found to be bimodal in spring and summer, and was trimodal in autumn. The activity time and frequency in autumn were significantly lower than the spring. (3) Animals possess the ability to integrate disparate sources of information about danger to optimize energy gain. The jerboa adapted different responses to predation risks and competition in different seasons according to the demand for food resources.

17.
Int J Biol Macromol ; 167: 1424-1434, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33202277

RESUMO

The increasing drug resistance of pathogenic bacteria is a crisis that threatens public health. Antimicrobial peptides (AMPs) have been suggested to be potentially effective alternatives to solve this problem. Here, we tested housefly Phormicin-derived peptides for effects on Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA) infections in vitro and in vivo. A decreased bacterial load of MRSA was observed in the mouse scald model after treatment with Phormicin and in the positive control group (vancomycin). A mouse scrape model indicated that Phormicin helps the host fight drug-resistant MRSA infections. The protective effect of Phormicin on MRSA was confirmed in the Hermetia illucens larvae model. Phormicin also disrupted the formation of S. aureus and MRSA biofilms. Furthermore, this effect coincided with the downregulation of biofilm formation-related gene expression (agrC, sigB, RNAIII, altA, rbf, hla, hld, geh and psmɑ). Notably, virulence genes and several regulatory factors were also altered by Phormicin treatment. Based on these findings, housefly Phormicin helps the host inhibit MRSA infection through effects on biofilm formation and related gene networks. Therefore, housefly Phormicin potential represents a candidate agent for clinical MRSA chemotherapy.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Moscas Domésticas/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , Aldeído Oxirredutases/metabolismo , Animais , Peptídeos Catiônicos Antimicrobianos/síntese química , Peptídeos Catiônicos Antimicrobianos/química , Proteínas de Bactérias/metabolismo , Peso Corporal , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Humanos , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/microbiologia , Masculino , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/metabolismo , Staphylococcus aureus Resistente à Meticilina/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , RNA Bacteriano/metabolismo , Fator sigma/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo , Staphylococcus aureus/fisiologia , Vancomicina/farmacologia
18.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 39(1): 71-8, 2010 01.
Artigo em Zh | MEDLINE | ID: mdl-20175239

RESUMO

OBJECTIVE: To construct a recombinant adenovirus vector containing bone morphogenic protein-7 (BMP-7) gene and to identify its biological activities in proximal tubule epithelial cells (PTECs). METHODS: Forty-six fragments of BMP-7 gene were obtained by PCR method and then were ligated to the full-length gene. The full length sequence of BMP-7 was subcloned into pBluescript II(+) vectors, and confirmed by sequencing. Double digested with Not I and Hind III, BMP-7 gene was inserted into pShuttle-CMV. EcoR I pre-linearized pShuttle plasmid was transformed into competence bacterium BJ5183 to obtain the recombinant adenovirus-BMP-7 by efficient homologous recombination. Then the AdBMP-7 was obtained by packaging Pac I linearized in 293 cells. Adenoviral titer was determined by adenovirus fluorescent detection kit. The protein expression of BMP-7 in PTECs was respectively detected by ELISA and Western blot. RT-PCR method was used for analyzing the alpha-smooth muscle action (alpha-SMA) expression in PTECs, which was treated consecutively with TGF-beta and AdBMP-7. RESULTS: The recombinant plasmid AdBMP-7 was successfully generated, which increased BMP-7 protein expression levels in PTECs, and down-regulated TGF-beta-induced alpha-SMA expression. CONCLUSION: The bioactive recombinant adenovirus AdBMP-7 has been successfully constructed, which may be effective in inhibition of chronic renal fibrosis.


Assuntos
Adenoviridae/metabolismo , Proteína Morfogenética Óssea 7/biossíntese , Células Epiteliais/metabolismo , Vetores Genéticos/genética , Túbulos Renais Proximais/metabolismo , Adenoviridae/genética , Animais , Sequência de Bases , Proteína Morfogenética Óssea 7/genética , Células Cultivadas , Túbulos Renais Proximais/citologia , Dados de Sequência Molecular , Ratos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética
19.
Ecol Evol ; 10(21): 12395-12406, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33537120

RESUMO

The objective of this study was to investigate the effects of grazing on midday gerbil (Meriones meridianus) population characteristics and survival of animals of different genders. The experiment used a randomized complete block design and was conducted in Alxa Left Banner, Inner Mongolia, China, in 2002 (The agricultural reclamation plots set up in 1994). From April 2006 to October 2010, midday gerbils were live-trapped in 3 light grazing plots, 3 overgrazed plots, and 3 grazing exclusion plots. The quantity of vegetation was investigated in the two different grazing intensity areas and grazing exclusion area to determine the relationship between gerbils and plant food availability. The results suggested that there was higher gerbil density, individual body mass, and daily body mass growth rate in the grazing exclusion sites than the other sites across the whole year. Females had higher survival in grazing exclusion areas than in other treatments, but the males' survival showed the opposite pattern. Our results indicated that grazing negatively influenced the midday gerbil population by reducing food availability. Grazing influenced the survival rates of male midday gerbils positively, but had negative effects on females. The reason for gendered differences in survival rates of midday gerbils requires further investigation.

20.
Huan Jing Ke Xue ; 40(8): 3633-3641, 2019 Aug 08.
Artigo em Zh | MEDLINE | ID: mdl-31854770

RESUMO

Focusing on the removal of ammonia nitrogen from polluted water, the absorption properties of five materials (zeolite, maifanite, diatomite, bentonite, and activated carbon) were tested. Results showed that the pseudo-second-order kinetic equation was suitable for data fitting for the five materials. The maximum theoretical adsorption capacities of the five materials were 2.0673 mg·g-1, 0.9982 mg·g-1, 0.7580 mg·g-1, 1.7486 mg·g-1, and 1.0160 mg·g-1, respectively, which were close to the experimental value. Chemical-based adsorption was the main mode of adsorption. Data for diatomite were fitted using the Langmuir isotherm equation, and belonged to the single-layer molecular adsorption group, while the other four materials were fitted using the Freundlich isotherm equation, belonging to the multi-layer molecular adsorption group. Moreover, the results showed that the removal rates of ammonia nitrogen by zeolite, diatomite, bentonite, and activated carbon increased with an increase in dosage, and the maximum removal rates were 100%, 10.46%, 49.25%, and 16.87%, respectively. A maifanite dosage of 0.4g achieved the maximum removal rate of 48.85%. At pH 4-10, the adsorption capacities of zeolite and maifanite first increased and then decreased, while that of diatomite, bentonite, and activated carbon slowly increased. The desorption capacity of the five tested materials increased with an increase in the initial concentration of ammonia nitrogen.

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