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1.
J Antimicrob Chemother ; 78(4): 1117-1124, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36883515

RESUMO

OBJECTIVES: To elucidate the role of a novel carbapenem-hydrolysing class D ß-lactamase (RAD-1) from Riemerella anatipestifer. METHODS: We applied WGS and bioinformatic analysis to screen putative ß-lactamase genes in R. anatipestifer SCVM0004. A putative class D ß-lactamase gene was cloned into pET24a and transferred into Escherichia coli BL21 (DE3) for antibiotic susceptibility determination and protein purification. Meanwhile, the purified native protein was used to determine the enzymatic activities. RESULTS: A class D ß-lactamase, RAD-1, was identified in the genome of R. anatipestifer SCVM0004. It was distinct from all characterized class D ß-lactamases (≤42% amino acid sequence identity). Searching in GenBank showed that blaRAD-1 was widely disseminated among R. anatipestifer. Genomic environment analysis indicated that the chromosomal structures of blaRAD-1-located regions were relatively conserved. Expression of RAD-1 in E. coli results in elevated MICs for various ß-lactam antibiotics, including penicillins, extended-spectrum cephalosporins, a monobactam and carbapenems. Moreover, kinetic analysis of purified RAD-1 revealed: (i) high-level activity against penicillins; (ii) highest affinity for carbapenems; (iii) moderate hydrolysis of extended-spectrum cephalosporins and a monobactam; and (iv) no activity for oxacillin and cefoxitin. CONCLUSIONS: This study identified a novel chromosomally located class D carbapenemase RAD-1 (Bush-Jacoby functional group 2def) in R. anatipestifer SCVM0004. Moreover, bioinformatic analysis confirmed that the RAD-1 was widely prevalent and conserved in R. anatipestifer.


Assuntos
Carbapenêmicos , Escherichia coli , Carbapenêmicos/farmacologia , Carbapenêmicos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Cinética , beta-Lactamases/metabolismo , Cefalosporinas , Monobactamas , Penicilinas
2.
Antimicrob Agents Chemother ; 66(3): e0175721, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-34978883

RESUMO

Whole-genome sequencing of Riemerella anatipestifer isolate RCAD0122 revealed a chromosomally located ß-lactamase gene, blaRAA-1, which encoded a novel class A extended-spectrum ß-lactamase (ESBL), RAA-1. RAA-1 shared ≤65% amino acid sequence identity with other characterized ß-lactamases. The kinetic assay of native purified RAA-1 revealed ESBL-like hydrolysis activity. Furthermore, blaRAA-1 could be transferred to a homologous strain by natural transformation. However, an epidemiological study showed that the blaRAA-1 gene is not prevalent currently.


Assuntos
Riemerella , Sequência de Aminoácidos , Riemerella/genética , Riemerella/metabolismo , beta-Lactamases/metabolismo
3.
Adv Atmos Sci ; 39(10): 1709-1720, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35669259

RESUMO

China national air quality monitoring network has become the core data source for air quality assessment and management in China. However, during network construction, the significant change in numbers of monitoring sites with time is easily ignored, which brings uncertainty to air quality assessments. This study aims to analyze the impact of change in numbers of stations on national and regional air quality assessments in China during 2013-18. The results indicate that the change in numbers of stations has different impacts on fine particulate matter (PM2.5) and ozone concentration assessments. The increasing number of sites makes the estimated national and regional PM2.5 concentration slightly lower by 0.6-2.2 µg m-3 and 1.4-6.0 µg m-3 respectively from 2013 to 2018. The main reason is that over time, the monitoring network expands from the urban centers to the suburban areas with low population densities and pollutant emissions. For ozone, the increasing number of stations affects the long-term trends of the estimated concentration, especially the national trends, which changed from a slight upward trend to a downward trend in 2014-15. Besides, the impact of the increasing number of sites on ozone assessment exhibits a seasonal difference at the 0.05 significance level in that the added sites make the estimated concentration higher in winter and lower in summer. These results suggest that the change in numbers of monitoring sites is an important uncertainty factor in national and regional air quality assessments, that needs to be considered in long-term concentration assessment, trend analysis, and trend driving force analysis.

4.
Sheng Li Xue Bao ; 72(6): 757-764, 2020 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-33349834

RESUMO

The aim of the present paper was to study the role of sodium calcium exchanger (NCX) in the generation of action potentials (APs) in cardiomyocytes during early developmental stage (EDS). The precisely dated embryonic hearts of C57 mice were dissected and enzymatically dissociated to single cells. The changes of APs were recorded by whole-cell patch-clamp technique before and after administration of NCX specific blockers KB-R7943 (5 µmol/L) and SEA0400 (1 µmol/L). The results showed that, both KB-R7943 and SEA0400 had potent negative chronotropic effects on APs of pacemaker-like cells, while such effects were only observed in some ventricular-like cardiomyocytes. The negative chronotropic effect of KB-R7943 on ventricular-like cardiomyocytes was accompanied by shortening of AP duration (APD), whereas such an effect of SEA0400 was paralleled by decrease in velocity of diastolic depolarization (Vdd). From embryonic day 9.5 (E9.5) to E10.5, the negative chronotropic effects of KB-R7943 and SEA0400 on ventricular-like APs of embryonic cardiomyocytes gradually disappeared. These results suggest that, in the short-term development of early embryo, the function of NCX may experience developmental changes as evidenced by different roles of NCX in autorhythmicity and APs generation, indicating that NCX function varies with different conditions of cardiomyocytes.


Assuntos
Cálcio , Miócitos Cardíacos , Potenciais de Ação , Animais , Cálcio/metabolismo , Camundongos , Miócitos Cardíacos/metabolismo , Sódio/metabolismo , Trocador de Sódio e Cálcio , Tioureia/farmacologia
5.
Zhongguo Zhong Yao Za Zhi ; 45(13): 2993-3000, 2020 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-32726003

RESUMO

To scientifically evaluate the intervention effect of Chinese medicine preventive administration(combined use of Huo-xiang Zhengqi Oral Liquid and Jinhao Jiere Granules) on community population in the case of coronavirus disease 2019(COVID-19), a large cohort, prospective, randomized, and parallel-controlled clinical study was conducted. Total 22 065 subjects were included and randomly divided into 2 groups. The non-intervention group was given health guidance only, while the traditional Chinese medicine(TCM) intervention group was given two coordinated TCM in addition to health guidance. The medical instructions were as follows. Huoxiang Zhengqi Oral Liquid: oral before meals, 10 mL/time, 2 times/day, a course of 5 days. Jinhao Jiere Granules: dissolve in boiling water and take after meals, 8 g/time, 2 times/day, a course of 5 days, followed up for 14 days, respectively. The study found that with the intake of medication, the incidence rate of TCM intervention group was basically maintained at a low and continuous stable level(0.01%-0.02%), while the non-intervention group showed an overall trend of continuous growth(0.02%-0.18%) from 3 to 14 days. No suspected or confirmed COVID-19 case occurred in either group. There were 2 cases of colds in the TCM intervention group and 26 cases in the non-intervention group. The incidence of colds in the TCM intervention group was significantly lower(P<0.05) than that in the non-intervention group. In the population of 16-60 years old, the incidence rate of non-intervention and intervention groups were 0.01% and 0.25%, respectively. The difference of colds incidence between the two groups was statistically significant(P<0.05). In the population older than 60 years old, they were 0.04% and 0.21%, respectively. The incidence of colds in the non-intervention group was higher than that in the intervention group, but not reaching statistical difference. The protection rate of TCM for the whole population was 91.8%, especially for the population of age 16-60(95.0%). It was suggested that TCM intervention(combined use of Huoxiang Zhengqi Oral Liquid and Jinhao Jiere Granules) could effectively protect community residents against respiratory diseases, such as colds, which was worthy of promotion in the community. In addition, in terms of safety, the incidence of adverse events and adverse reactions in the TCM intervention group was relatively low, which was basically consistent with the drug instructions.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Medicamentos de Ervas Chinesas , Pandemias , Pneumonia Viral , Adolescente , Adulto , COVID-19 , Infecções por Coronavirus/tratamento farmacológico , Humanos , Medicina Tradicional Chinesa , Pessoa de Meia-Idade , Pneumonia Viral/tratamento farmacológico , Estudos Prospectivos , SARS-CoV-2 , Adulto Jovem , Tratamento Farmacológico da COVID-19
6.
Mol Reprod Dev ; 86(11): 1720-1730, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31489750

RESUMO

Lactate produced by glycolysis in Sertoli cells (SCs) is the main energy substrate for developing germ cells and plays a vital role in spermatogenesis. MicroRNAs (miRNAs) function as posttranscriptional regulators of gene expression in biological processes. We have previously shown that hyperthermia (43°C, 30 min) promotes lactate secretion by inhibiting phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) in cultured immature boar SCs. However, it is unclear whether miRNAs are involved in AMPK-modulated glycolysis in SCs. In the present study, we identified 349 miRNAs (227 upregulated and 122 downregulated) in hyperthermia-treated boar SCs by next-generation high-throughput RNA sequencing. MiR-8-3p, which was found to be a novel upregulated miRNA in hyperthermia-treated SCs, suppressed the expression of AMPK upstream genes (protein phosphatase 2 subunit B, PPP2R5B), and further downregulated the expression of p-AMPK. The miR-8-3p mimic upregulated expression of glucose transporter 3, lactate dehydrogenase A and monocarboxylate transporter 1, and increased lactic acid dehydrogenase activity, lactate secretion, and ATP depletion in SCs; the miR-8-3p inhibitor had the opposite effects on these parameters. Our findings indicate that miR-8-3p acts as a novel regulator of AMPK-modulated lactate secretion by targeting PPP2R5B in hyperthermic boar SCs.


Assuntos
Resposta ao Choque Térmico , Ácido Láctico/metabolismo , MicroRNAs/metabolismo , Proteína Fosfatase 2/metabolismo , Células de Sertoli/metabolismo , Animais , Masculino , Suínos
7.
Reprod Fertil Dev ; 31(10): 1616-1627, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31242957

RESUMO

As an important gram-negative bacterial outer membrane component, lipopolysaccharide (LPS) plays an important role in bacterial-induced endometritis in sows. However, how LPS induces endometritis is unclear. We stimulated sow endometrial epithelial cells (EECs) with LPS and detected cell viability and tumour necrosis factor-α (TNF-α) and interleukin-1 (IL-1) secretion. LPS affected EEC viability and TNF-α and IL-1 secretion in a dose-dependent manner. LPS induced differential expression in 10 of 393 miRNAs in the EECs (downregulated, nine; upregulated, one). MicroRNA (miRNA) high-throughput sequencing of the LPS-induced EECs plus bioinformatics analysis and the dual-luciferase reporter system revealed a novel miRNA target gene: mitogen-activated protein kinase kinase kinase 14 (MAP3K14). Ssc-novel-miR-106-5p mimic, inhibitor and the nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκBα) phosphorylation inhibitor Bay11-7085 were used to detect EEC nuclear factor-κB phosphorylation levels (p-NF-κB) and TNF-α and IL-1 secretion. MiR-106-5p mimic downregulated MAP3K14 mRNA and protein expression levels, inhibited p-NF-κB levels and decreased IL-1 and TNF-α secretion, whereas miR-106-5p inhibitor had the opposite effect. Bay11-7085 inhibited p-NF-κB expression and TNF-α and IL-1 secretion. These results suggest that LPS downregulates ssc-novel-miR-106-5p expression in sow EECs to increase MAP3K14 expression, which increases p-NF-κB to promote IL-1 and TNF-α secretion.


Assuntos
Endométrio/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Inflamação/induzido quimicamente , Lipopolissacarídeos/farmacologia , MicroRNAs/fisiologia , Proteínas Serina-Treonina Quinases/genética , Animais , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Endometrite/induzido quimicamente , Endometrite/genética , Endometrite/metabolismo , Endometrite/veterinária , Endométrio/imunologia , Endométrio/metabolismo , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Inflamação/genética , Inflamação/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Suínos , Quinase Induzida por NF-kappaB
8.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 36(4): 627-632, 2019 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-31441264

RESUMO

The quality inspection of magnetic resonance imaging (MRI) performance parameters is an important means to ensure the image quality and the reliability of diagnosis results. There are some problems in the manual calculation and eye recognition of the quality inspection parameters, such as strong subjectivity and low efficiency. In view of these facts, an automatic analysis system for MRI quality detection based on QT is proposed and implemented in C++ language. The image processing algorithm is introduced to automatically measure and calculate the quality inspection parameters. The software with comprehensive functions is designed to systematically manage the quality inspection information of MRI. The experimental results show that the automatically calculated parameters are consistent with the manually calculated ones. Accordingly, the accuracy and reliability of the algorithm is verified. The whole system is efficient, convenient and easy to operate, and it can meet the actual needs of MRI quality inspection.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/normas , Algoritmos , Reprodutibilidade dos Testes
9.
Biochem Biophys Res Commun ; 491(4): 1112-1117, 2017 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-28797567

RESUMO

Dietary deficiency of n-3 polyunsaturated fatty acids (PUFAs) is involved in the pathophysiology and etiology of major depressive disorder. Supplementation with docosahexaenoic acid (DHA) exerts antidepressant-like effect; however, the molecular mechanism of DHA action remains unclear. Here we examined the effects of DHA on the modulation of glial cell line-derived neurotrophic factor (GDNF), which is essential for neural development, plasticity, neurogenesis, and survival. We demonstrated that DHA treatment significantly increased GDNF release in a concentration dependent manner in rat C6 glioma cells (C6 cells) and primary cultured rat astrocytes, which is also associated with increased expression of GDNF mRNA. Furthermore, the DHA-induced GDNF production was inhibited by mitogen activated protein kinase (MEK) inhibitor and protein kinase C (PKC) inhibitor, but not protein kinase A (PKA) inhibitor and p38 mitogen-activated protein kinase (MAPK) inhibitor. DHA-induced extracellular signal-regulated kinase (ERK) activation is dependent on the PKC, as demonstrated by its reversibility after pretreatment with PKC inhibitor. Moreover, fibroblast growth factor receptor (FGFR inhibitor) but not epidermal growth factor receptor (EGFR) inhibitor blocked the activation of ERK induced by DHA treatment. DHA-induced GDNF production was also blocked by FGFR inhibitor, suggesting that FGFR is also involved in ERK activation-mediated GDNF production induced by DHA. Our study demonstrates that DHA-induced release of GDNF, mediated by PKC and FGFR-dependent on ERK activation, may contribute to the antidepressant-like effect of DHA.


Assuntos
Antidepressivos/farmacologia , Ácidos Docosa-Hexaenoicos/farmacologia , Fator Neurotrófico Derivado de Linhagem de Célula Glial/biossíntese , Glioma/metabolismo , Animais , Relação Dose-Resposta a Droga , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fator Neurotrófico Derivado de Linhagem de Célula Glial/antagonistas & inibidores , Glioma/patologia , Ratos , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
10.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 33(5): 972-8, 2016 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-29714953

RESUMO

Magnetoelastic(ME)sensors,characterized by wireless,passive,low cost and high sensitivity,have widespread applications in various fields.However,its defects of large volume,high power consumption,poor portability and inconveniency for use limit the application prospects of the ME sensors.To solve this problem,the present paper shows a portable,low-power,resonance-type ME sensor detecting system based on STM32.The experimental results indicated that this detecting system allowed the ME sensor to complete the measurement of resonant frequency in different medium and different concentration,with a frequency resolution of less than 1Hz,and the resonant frequency ratio of ME sensors in different sizes 0.933 8,closing the theoretical value of 0.942 3.Moreover,compared with the traditional impedance analyzer combined detecting system and the existing integrated detecting system,the present system has a power consumption of 0.68 Win operation and of only 2.20 mW in the dormancy mode.Therefore,the system can not only replace the original impedance analyzer combined detecting system,but also significantly improve the power control of the existing integrated detecting system,exhibiting the advantages of higher integration,portable measurement,and fine suitability for long-term monitoring.


Assuntos
Magnetismo , Tecnologia sem Fio , Impedância Elétrica
11.
Cell Physiol Biochem ; 37(2): 527-36, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26330232

RESUMO

BACKGROUND/AIMS: Puerarin shows a wide range of biological activities, including affecting the cardiac differentiation from murine embryonic stem (mES) cells. However, little is known about its effect and mechanism of action on the self-renewal of mES cells. This study aimed to determine the effect of puerarin on the self-renewal and pluripotency of mES cells and its underlying mechanisms. METHODS: RT-PCR and real-time PCR were used to detect the transcripts of core transcription factors, specific markers for multiple lineages, REST and microRNA-21 (miR-21). Colony-forming assay was performed to estimate the self-renewal capacity of mES cells. Western blotting and wortmannin were employed to explore the role of PI3K/Akt signaling pathway in the inhibitory action of puerarin on REST transcript. Transfected mES cells with antagomir21 were used to confirm the role of miR-21 in the action of puerarin on cell self-renewal. RESULTS: Puerarin significantly decreased the percentage of the self-renewal colonies, and suppressed the transcripts of Oct4, Nanog, Sox2, c-Myc and REST. Besides, PECAM, NCAM and miR-21 were up-regulated both under the self-renewal conditions and at day 4 of differentiation. The PI3K inhibitor wortmannin successfully reversed the mRNA expression changes of REST, Nanog and Sox2. Transfection of antagomir21 efficiently reversed the effects of puerarin on mES cells self-renewal. CONCLUSION: Inhibition of REST-miR-21 regulatory pathway may be the key mechanism of puerarin-induced suppression of mES cells self-renewal.


Assuntos
Isoflavonas/farmacologia , MicroRNAs/genética , Células-Tronco Embrionárias Murinas/citologia , Proteínas Repressoras/genética , Vasodilatadores/farmacologia , Androstadienos/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Autorrenovação Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Camundongos , MicroRNAs/metabolismo , Células-Tronco Embrionárias Murinas/efeitos dos fármacos , Células-Tronco Embrionárias Murinas/metabolismo , Proteínas Repressoras/metabolismo , Transdução de Sinais/efeitos dos fármacos , Wortmanina
12.
Cell Physiol Biochem ; 35(5): 1868-76, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25871338

RESUMO

BACKGROUND: Traditional Chinese herbal medicines (TCMs) have been widely used against a broad spectrum of biological activities, including influencing the cardiac differentiation from mouse embryonic stem cells (mESCs). However, their effects and mechanisms of action on ESCs proliferation remain to be determined. The present study aimed to determine the effect of three TCMs, baicalin, ginsenoside Rg1, and puerarin, on mESCs proliferation and to elucidate the possible mechanism of their action. METHODS: Cell proliferation was examined with a cell proliferation assay Cell Counting Kit-8 (CCK-8), propidium iodide (PI) staining was used to visualize cell cycle. The mRNA expression level of c-myc, c-fos, c-jun, GAPDH and microRNAs were measured by quantitative real time RT-PCR. RESULTS: We found that baicalin 50 µM suppressed the proliferation of mESCs as observations in more cells in G1 phase and less cells in either S phase or G2/M phase. Moreover, baicalin suppressed the expressions of c-jun and c-fos in mESCs and down-regulated the expression of miR-294. Overexpression of miR-294 in mESCs significantly reversed the effects of baicalin both on mESC proliferation and c-fos/c-jun expression. CONCLUSIONS: Baicalin down-regulation of miR-294 may be its key mechanism of action in decreasing mESCs proliferation.


Assuntos
Proliferação de Células/efeitos dos fármacos , Flavonoides/farmacologia , MicroRNAs/metabolismo , Animais , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/efeitos dos fármacos , Células-Tronco Embrionárias/metabolismo , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Medicina Tradicional Chinesa , Camundongos , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-fos/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo
13.
Mol Reprod Dev ; 82(11): 880-91, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26256020

RESUMO

Lipopolysaccharide (LPS) induces germ cell apoptosis, but its mechanism of action is not clear. One possibility is that LPS regulates the expression of FAS ligand (FASLG) in Sertoli cells, which will then influence germ cell apoptosis. In this study, LPS reduced the viability of cultured, immature boar Sertoli cells in a time- and dose-dependent manner; enhanced the production of pro-inflammatory cytokines including tumor necrosis factor α (TNFA), interleukin-1ß (IL1B), nitric oxide (NO), and transforming growth factor-ß (TGFB); and increased the expression of FASLG in a dose-dependent manner. While 10 µg/ml LPS enhanced the expression of FASLG, reduced cell cycle progression, and impaired the ultrastructure of Sertoli cells, this dose did not induce apoptosis. LPS also had no effect on the activity or expression of matrix metalloproteinases 2 or 9 (MMP2 or MMP9). In contrast, the expression of ssc-miR-187 increased following LPS challenge, and inhibition of ssc-miR-187 blocked LPS-induced expression of FASLG. Our results therefore suggest that LPS reduces the viability of and enhances FASLG expression in cultured, immature boar Sertoli cells through elevated secretion of TNFA, IL1B, NO, and TGFB as well as through the regulation of ssc-miR-187 potency.


Assuntos
Citocinas/biossíntese , Proteína Ligante Fas/biossíntese , Regulação da Expressão Gênica/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , MicroRNAs/biossíntese , Células de Sertoli/metabolismo , Animais , Células Cultivadas , Masculino , Células de Sertoli/citologia , Suínos
14.
Avian Pathol ; 44(3): 162-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25690020

RESUMO

Riemerella anatipestifer is a major bacterial pathogen of waterfowl, globally responsible for avian septicaemic disease. As chemotherapy is the predominant method for the prevention and treatment of R. anatipestifer infection in poultry, the widespread use of antibiotics has favoured the emergence of antibiotic-resistant strains. However, little is known about R. anatipestifer susceptibility to macrolide antibiotics and its resistance mechanism. We report for the first time the identification of a macrolide resistance mechanism in R. anatipestifer that is mediated by the ribosomal RNA methyltransferase ermF. We identified the presence of the ermF gene in 64/206 (31%) R. anatipestifer isolates from different regions in China. An ermF deletion strain was constructed to investigate the function of the ermF gene on the resistance to high levels of macrolides. The ermF mutant strain showed significantly decreased resistance to macrolide and lincosamide, exhibiting 1024-, 1024-, 4- and >2048-fold reduction in the minimum inhibitory concentrations for erythromycin, azithromycin, tylosin and lincomycin, respectively. Furthermore, functional analysis of ermF expression in E. coli XL1-blue showed that the R. anatipestifer ermF gene was functional in E. coli XL1-blue and conferred resistance to high levels of erythromycin (100 µg/ml), supporting the hypothesis that the ermF gene is associated with high-level macrolide resistance. Our work suggests that ribosomal RNA modification mediated by the ermF methyltransferase is the predominant mechanism of resistance to erythromycin in R. anatipestifer isolates.


Assuntos
Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/genética , Resistência Microbiana a Medicamentos/genética , Metiltransferases/genética , Riemerella/enzimologia , Antibacterianos/farmacologia , Azitromicina , China , Eletroforese em Gel de Poliacrilamida , Eritromicina , Escherichia coli , Lincomicina , Macrolídeos/farmacologia , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Riemerella/efeitos dos fármacos , Riemerella/genética , Tilosina
15.
Cell Physiol Biochem ; 34(2): 383-92, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25059232

RESUMO

AIMS: The embryonic stem cell-derived cardiomyocytes (ES-CM) is one of the promising cell sources for repopulation of damaged myocardium. However, ES-CMs present immature structure, which impairs their integration with host tissue and functional regeneration. This study used murine ES-CMs as an in vitro model of cardiomyogenesis to elucidate the effect of puerarin, the main compound found in the traditional Chinese medicine the herb Radix puerariae, on t-tubule development of murine ES-CMs. METHODS: Electron microscope was employed to examine the ultrastructure. The investigation of transverse-tubules (t-tubules) was performed by Di-8-ANEPPS staining. Quantitative real-time PCR was utilized to study the transcript level of genes related to t-tubule development. RESULTS: We found that long-term application of puerarin throughout cardiac differentiation improved myofibril array and sarcomeres formation, and significantly facilitated t-tubules development of ES-CMs. The transcript levels of caveolin-3, amphiphysin-2 and junctophinlin-2, which are crucial for the formation and development of t-tubules, were significantly upregulated by puerarin treatment. Furthermore, puerarin repressed the expression of miR-22, which targets to caveolin-3. CONCLUSION: Our data showed that puerarin facilitates t-tubule development of murine ES-CMs. This might be related to the repression of miR-22 by puerarin and upregulation of Cav3, Bin1 and JP2 transcripts.


Assuntos
Células-Tronco Embrionárias/citologia , Isoflavonas/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Sequência de Bases , Caveolina 3/genética , Diferenciação Celular , Primers do DNA , Proteínas de Membrana/genética , Camundongos , MicroRNAs/genética , Microscopia Eletrônica de Transmissão , Proteínas Musculares/genética , Miócitos Cardíacos/citologia , Miócitos Cardíacos/ultraestrutura , Proteínas do Tecido Nervoso/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Supressoras de Tumor/genética , Regulação para Cima/efeitos dos fármacos
16.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 31(3): 558-62, 2014 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-25219234

RESUMO

Aiming at the single treatment and the design separation between treatment and assessment in electrotherapy equipment, a kind of system including low-intermediate frequency treatment and efficacy evaluation was developed. With C8051F020 single-chip microcomputer as the core and the circuit design and software programming used, the system realized the random switch of therapeutic parameters, the collection, display and data storage of pressure pain threshold in the assessment. Experiment results showed that the stimulus waveform, current intensity, frequency, duty ratio of the system output were adjustable, accurate and reliable. The obtained pressure pain threshold had a higher accuracy (< 0.3 N) and better stability, guiding the parameter choice in the precise electrical stimulation. It, therefore, provides a reliable technical support for the treatment and curative effect assessment.


Assuntos
Terapia por Estimulação Elétrica/instrumentação , Medição da Dor/instrumentação , Desenho de Equipamento , Microcomputadores , Software
17.
Sci Total Environ ; 919: 170895, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38346652

RESUMO

Turbulent motion is the essential difference between the atmospheric boundary layer and the free atmosphere. Due to the lack of detection methods for vertical turbulent structures, commonly used methods usually focus on material distribution, thermal effects, or dynamic effects, and they fail to reflect the boundary layer objectively in terms of turbulence. Therefore, to date, the acquisition and characteristic analysis of the atmospheric boundary layer height under turbulent angles have not been achieved. This study proposes a method for obtaining the height of the boundary layer based on the power-law exponent of atmospheric turbulence. The proposed method is validated and analyzed with data from radiosondes obtained under sunny, cloudy, and light rain weather conditions, demonstrating its advantages. With the proposed method, the first published acquisition of boundary layer height characteristics based on turbulent motion is achieved, including a statistical analysis of the daily and monthly variation characteristics of the boundary layer height over the Shenzhen area in China. Moreover, different oscillation frequencies of the boundary layer height under different wind directions are revealed. The results of this study break the traditional bottleneck of not being able to obtain the height of the boundary layer based on turbulence, and provide a new perspective for the acquisition and research of the boundary layer height.

18.
Mol Immunol ; 166: 65-78, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38244370

RESUMO

Diabetic nephropathy(DN) remains a significant risk factor for cardiovascular and all-cause mortality, and end-stage renal disease (ESRD) associated with it is growing in prevalence.However, there is absolutely no curative strategy for DN. We subjected db/db and control mouse kidneys to transcriptional sequencing analysis to obtain transcriptome expression profile data in the diabetic nephropathy.We next performed differential analysis of db/db and control mice kidney sequencing data to obtain differentially expressed genes. The differential expressed genes were intersected with the oxidative stress and inflammatory response related genes derived from the MGI/MsiDB gene set to yield oxidative stress inflammatory response related differential 122 genes (OIRDEGs). To further clarify the biological functions of DEGs, we conducted GOKEGG analysis and obtained the top 20 genes by five computational algorithms of the cytohubba plugin via cytoscape, respectively. The genes obtained by the five algorithms were intersected and the intersection genes were considered as key genes,including Cd40lg, Il2rb, Lck, Il2rg, Zap70, Serpinb1a. Also,we used GSEA and immune infiltration analysis to clarify the biological signaling pathways and immune cell infiltration that are substantial in the diabetic nephropathy.Correlation studies of key genes with immune cell infiltration revealed that they were correlated with the majority types of T cells while only with two types of B cells.Then, we predicted miRNA and TF for the key genes and constructed the interaction network. Finally, the expression differences of key genes were examined by validation dataset and RT-PCR experiment.In conclusion,we have identified key genes associated with T cell immune response in a diabetic nephropathy model, which bear significance in the etiopathogenesis of immunological injury in diabetic nephropathy and provide an innovative proposal for the recognition and management of DN.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Serpinas , Animais , Camundongos , Nefropatias Diabéticas/genética , Algoritmos , Linfócitos B , Ligante de CD40 , Biologia Computacional
19.
Genes Genomics ; 46(5): 621-635, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38536617

RESUMO

BACKGROUND: TFP5 is a Cdk5 inhibitor peptide, which could restore insulin production. However, the role of TFP5 in diabetic nephropathy (DN) is still unclear. OBJECTIVE: This study aims to characterize the transcriptome profiles of mRNA and lncRNA in TFP5-treated DN mice to mine key lncRNAs associated with TFP5 efficacy. METHODS: We evaluated the role of TFP5 in DN pathology and performed RNA sequencing in C57BL/6J control mice, C57BL/6J db/db model mice, and TFP5 treatment C57BL/6J db/db model mice. The differentially expressed lncRNAs (DElncRNAs) and mRNAs (DEmRNAs) were analyzed. WGCNA was used to screen hub-gene of TFP5 in treatment of DN. RESULTS: Our results showed that TFP5 therapy ameliorated renal tubular injury in DN mice. In addition, compared with the control group, the expression profile of lncRNAs in the model group was significantly disordered, while TFP5 alleviated the abnormal expression of lncRNAs. A total of 67 DElncRNAs shared among the three groups, 39 DElncRNAs showed a trend of increasing in the DN group and decreasing after TFP treatment, while the remaining 28 showed the opposite trend. DElncRNAs were enriched in glycosphingolipid biosynthesis signaling pathways, NF-κB signaling pathways, and complement activation signaling pathways. There were 1028 up-regulated and 1117 down-regulated DEmRNAs in the model group compared to control group, and 123 up-regulated and 153 down-regulated DEmRNAs in the TFP5 group compared to the model group. The DEmRNAs were involved in PPAR and MAPK signaling pathway. We confirmed that MSTRG.28304.1 is a key DElncRNA for TFP5 treatment of DN. TFP5 ameliorated DN maybe by inhibiting MSTRG.28304.1 through regulating the insulin resistance and PPAR signaling pathway. The qRT-PCR results confirmed the reliability of the sequencing data through verifying the expression of ENSMUST00000211209, MSTRG.31814.5, MSTRG.28304.1, and MSTRG.45642.14. CONCLUSION: Overall, the present study provides novel insights into molecular mechanisms of TFP5 treatment in DN.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , RNA Longo não Codificante , Camundongos , Animais , Transcriptoma , Nefropatias Diabéticas/genética , Nefropatias Diabéticas/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Perfilação da Expressão Gênica/métodos , Reprodutibilidade dos Testes , Receptores Ativados por Proliferador de Peroxissomo/genética , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética
20.
Sci Total Environ ; 931: 172873, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38692330

RESUMO

Carbapenem resistance's global proliferation poses a significant public health challenge. The primary resistance mechanism is carbapenemase production. In this study, we discovered a novel carbapenemase, RATA, located on the chromosome of Riemerella anatipestifer isolates. This enzyme shares ≤52 % amino acid sequence identity with other known ß-lactamases. Antimicrobial susceptibility tests and kinetic assays demonstrated that RATA could hydrolyze not only penicillins and extended-spectrum cephalosporins but also monobactams, cephamycins, and carbapenems. Furthermore, its activity was readily inhibited by ß-lactamase inhibitors. Bioinformatic analysis revealed 46 blaRATA-like genes encoding 27 variants in the NCBI database, involving 21 different species, including pathogens, host-associated bacteria, and environmental isolates. Notably, blaRATA-positive strains were globally distributed and primarily collected from marine environments. Concurrently, taxonomic analysis and GC content analysis indicated that blaRATA orthologue genes were predominantly located on the chromosomes of Flavobacteriaceae and shared a similar GC content as Flavobacteriaceae. Although no explicit mobile genetic elements were identified by genetic environment analysis, blaRATA-2 possessed the ability of horizontal transfer in R. anatipestifer via natural transformation. This work's data suggest that RATA is a new chromosome-encoded class A carbapenemase, and Flavobacteriaceae from marine environments could be the primary reservoir of the blaRATA gene.


Assuntos
Proteínas de Bactérias , beta-Lactamases , beta-Lactamases/genética , beta-Lactamases/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Carbapenêmicos/farmacologia
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