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1.
J Tradit Chin Med ; 34(3): 357-61, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24992765

RESUMEN

OBJECTIVE: To observe the impact of total flavonoids from Ganshanbian (Herba Hyperici Attenuati) on the expression of vascular smooth muscle membrane L-type calcium channel alpha1 C subunit (CaL-alpha1C) and ATP-sensitive K+ channel (K(ATP))-Kir6.1 mRNA, and explore the mechanisms of the antiarrhythmic effect of Ganshanbian (Herba Hyperici Attenuati) total flavonoids. METHODS: The treatment group was fed total flavonoids from Ganshanbian (Herba Hyperici Attenuati) for 7 days by gavage with 100 mg x kg(-1) x d(-1). The blank control group and model control group were given the same amount of normal saline for 7 d. Arrhythmias were induced by performing a myocardial ischemia-reperfusion and electrocardiogram was observed. Reverse transcription-polymerase chain reaction was used to detect the expression of CaL-alpha 1C and K(ATP)-Kir6.1 mRNA in the myocardial cell membrane of all groups of rats. RESULTS: Total flavonoids from Ganshanbian (Herba Hyperici Attenuati) can delay the appearance of myocardial ischemia reperfusion arrhythmias, shorten the duration of myocardial ischemia reperfusion arrhythmias, reduce heart rate, reduce cell membrane expression of CaL-a1C mRNA and enhance the expression of K(ATP)-Kir6.1 mRNA in myocardial ischemia-reperfusion arrhythmic rats. CONCLUSION: Total flavonoids from Ganshanbian (Herba Hyperici Attenuati) can alleviate arrhythmias by affecting the expression of L-type calcium channels and ATP-sensitive K+ channels.


Asunto(s)
Antiarrítmicos/administración & dosificación , Arritmias Cardíacas/tratamiento farmacológico , Canales de Calcio Tipo L/genética , Membrana Celular/metabolismo , Medicamentos Herbarios Chinos/administración & dosificación , Flavonoides/administración & dosificación , Canales KATP/genética , Isquemia Miocárdica/tratamiento farmacológico , Animales , Arritmias Cardíacas/genética , Arritmias Cardíacas/metabolismo , Canales de Calcio Tipo L/metabolismo , Membrana Celular/efectos de los fármacos , Femenino , Humanos , Canales KATP/metabolismo , Masculino , Isquemia Miocárdica/genética , Isquemia Miocárdica/metabolismo , Miocitos Cardíacos/metabolismo , Ratas , Ratas Sprague-Dawley
2.
Sleep Med ; 119: 164-171, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38685163

RESUMEN

AIM: To evaluate the prospective associations of nighttime sleep duration, midday napping, and sleep quality during early pregnancy with gestational diabetes mellitus (GDM) risk among Chinese pregnant women. METHODS: Sleep-related information was assessed by the Pittsburgh Sleep Quality Index in baseline surveys during the 6-15 (mean 10.3) gestational weeks. GDM was diagnosed during 24-28 gestational weeks according to the Chinese Guidelines on Diagnosis and Management of Hyperglycemia in Pregnancy (2022). Multivariable logistic regression models with adjustments for socio-demographic and lifestyle factors were used to estimate odds ratios (ORs) and 95 % confidence intervals (CIs) for the associations of sleep traits with GDM risk. RESULTS: We identified 503 incident GDM cases among 6993 participants. Compared with women who slept for 7-9 hours/night in early pregnancy, those who slept <7 hours/night showed a higher risk of GDM (OR, 1.75; 95 % CI: 1.20-2.54), whereas those who slept >9 hours/night showed no significant association for GDM risk (OR, 1.01; 95 % CI: 0.78-1.30). Compared with women with absolutely no napping, those with ≤60 and > 60 min/day midday napping showed no significant association for GDM risk (OR, 0.82; 95 % CI: 0.64-1.05 for ≤60 min/day midday napping; OR, 0.87; 95 % CI: 0.66-1.15 for >60 min/day midday napping). Poor sleep quality was not associated with GDM risk compared with good quality (OR, 0.90; 95 % CI: 0.72-1.12). CONCLUSION: A short nighttime sleep duration during early pregnancy was associated with a higher risk of GDM, which was independent of midday napping, sleep quality and lifestyle factors.


Asunto(s)
Diabetes Gestacional , Calidad del Sueño , Sueño , Humanos , Femenino , Diabetes Gestacional/epidemiología , Embarazo , Estudios Prospectivos , China/epidemiología , Adulto , Sueño/fisiología , Factores de Riesgo , Factores de Tiempo , Estudios de Cohortes , Encuestas y Cuestionarios , Duración del Sueño
3.
ACS Appl Mater Interfaces ; 16(15): 19421-19431, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38568871

RESUMEN

The employment of flexible piezoresistive sensors has sparked growing interest within the realm of wearable electronic devices, specifically in the fields of health detection and e-skin. Nevertheless, the advancement of piezoresistive sensors has been impeded by their limited sensitivity and restricted operating ranges. Consequently, it is imperative to fabricate sensors with heightened sensitivity and expanded operating ranges through the utilization of the appropriate methodologies. In this paper, piezoresistive sensors were fabricated utilizing electrospun polyvinylidene fluoride/polyacrylonitrile/polyethylene-polypropylene glycol multilayer fibrous membranes anchored with polypyrrole granules as the sensing layer, while electrospun thermoplastic polyurethane (TPU) fibers were employed as the flexible substrate. The sensitivity of the sensor is investigated by varying the fiber diameter of the sensing layer. The experimental findings reveal that a concentration of 14 wt % in the spinning solution exhibits high sensitivity (996.7 kPa-1) within a wide working range (0-10 kPa). This is attributed to the favorable diameter of the fibers prepared at this concentration, which facilitates the uniform in situ growth of pyrrole. The highly deformable TPU flexible fibers and multilayer sensing layer structure enable different linear responses across a broad pressure range (0-1 MPa). Furthermore, the sensor demonstrates good cyclic stability and can detect human movements under different pressures. These results suggest that the piezoresistive sensor with a wide operating range and high sensitivity has significant potential for future health monitoring and artificial intelligence applications.

4.
BMC Microbiol ; 13: 234, 2013 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-24144168

RESUMEN

BACKGROUND: Acinetobacter baumannii is a notorious opportunistic pathogen mainly associated with hospital-acquired infections. Studies on the clonal relatedness of isolates could lay the foundation for effective infection control. A snapshot study was performed to investigate the clonal relatedness of A. baumannii clinical isolates in our local settings. RESULTS: Among 82 non-repetitive Acinetobacter spp. clinical isolates that were recovered during a period of four days in 13 hospitals in Sichuan, Southwest China, 67 isolates were identified as A. baumannii. Half of the 67 A. baumannii isolates were non-susceptible to carbapenems. bla(OXA-23) was the only acquired carbapenemase gene detected, present in 40 isolates including five carbapenem-susceptible ones. The isolates belonged to 62 pulsotypes determined by PFGE and 31 sequence types (ST) by multi-locus sequence typing. Forty-three isolates belonged to the globally-disseminated clonal complex 92, among which ST75, ST92 and ST208 were the most common sequence types. CONCLUSIONS: Clinical isolates of A. baumannii were diverse in clonality in this snapshot study. However, most of the isolates belonged to the globally-distributed clonal complex CC92. ST75, ST92 and ST208 were the most common types in our region. In particular, ST208 might be an emerging lineage carrying bla(OXA-23).


Asunto(s)
Infecciones por Acinetobacter/microbiología , Acinetobacter baumannii/clasificación , Acinetobacter baumannii/genética , Variación Genética , Infecciones por Acinetobacter/epidemiología , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/aislamiento & purificación , Antibacterianos/farmacología , Carbapenémicos/farmacología , China/epidemiología , Análisis por Conglomerados , Estudios Transversales , Electroforesis en Gel de Campo Pulsado , Genotipo , Hospitales , Humanos , Epidemiología Molecular , Tipificación de Secuencias Multilocus , Resistencia betalactámica
5.
Am J Clin Nutr ; 117(6): 1353-1361, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37062367

RESUMEN

BACKGROUND: Evidence regarding prepregnancy weight change and gestational diabetes mellitus (GDM) is lacking among East Asian women. OBJECTIVES: Our study aimed to investigate the association between weight change from age 18 y to pregnancy and GDM in Chinese pregnant women. METHODS: Our analyses included 6972 pregnant women from the Tongji-Shuangliu Birth Cohort. Body weights were recalled for age 18 y and the time point immediately before pregnancy, whereas height was measured during early pregnancy. Prepregnancy weight change was calculated as the difference between weight immediately before pregnancy and weight at age 18 y. GDM outcomes were ascertained by 75-g oral-glucose-tolerance test. Multivariable logistic regression models were used to examine the association between prepregnancy weight change and risk of GDM. RESULTS: In total, 501 (7.2%) developed GDM in the cohort. After multivariable adjustments, prepregnancy weight change was linearly associated with a higher risk of GDM (P < 0.001). Compared with participants with stable weight (weight change within 5.0 kg) before pregnancy, multivariable-adjusted odds ratios and 95% confidence intervals were 1.55 (1.22, 1.98) and 2.24 (1.78, 2.83) for participants with moderate (5-9.9 kg) and high (≥10 kg) weight gain, respectively. In addition, overweight/obesity immediately before pregnancy mediated 17.6% and 31.7% of the associations of moderate and high-weight gain with GDM risk, whereas weekly weight gain during pregnancy mediated 21.1% and 22.7% of the associations. CONCLUSIONS: Weight gain from age 18 y to pregnancy was significantly associated with a higher risk of GDM. Maintaining weight stability, especially prevention of excessive weight gain from early adulthood to pregnancy, could be a potential strategy to reduce GDM risk.


Asunto(s)
Diabetes Gestacional , Aumento de Peso , Adolescente , Adulto , Femenino , Humanos , Embarazo , Índice de Masa Corporal , Pueblos del Este de Asia , Sobrepeso/complicaciones , Mujeres Embarazadas , Factores de Riesgo , Adulto Joven
6.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 42(5): 661-5, 2011 Sep.
Artículo en Zh | MEDLINE | ID: mdl-22007494

RESUMEN

OBJECTIVE: To investigate the correlation between the phenotype and expression level of femB of Staphylococcus aureus (MRSA), to discuss the mechanism of different phenotypes in methicillin-resistant Staphylococcus aureus. METHODS: The minimal inhibitory concentrations (MICs) of oxacillin against 71 clinical isolates of Staphylococcus aureus were determined by agar dilution method according to NCCLS. The production of beta-lactamase was identified by Cefinase paper strip method. The isolation rate of beta-lactamase-producing strains was counted and the correlation between the resistance phenotype and isolation rate of beta-lactamase was analysed by statistics. Real time fluorescent quantitative PCR was used to quantify the mRNA expression of femB of non-beta-lactamase-producing strains. RESULTS: The resistance rate of 71 Staphylococcus aureus to oxacillin was 66.20% (47/71), the isolation rate of beta-lactamase-producing MSSA strains was 58.3%,and that of strains of high- and low-level resistance to oxacillin were 63.15% and 55.56%. The standard curve was performed by series dilution of the heterogeneous resistant strain BB270, and the amount of femB-specific mRNA in strain BB270 was set to be 1. The calculated femB amounts in MSSA strains were from 0.4830-3.3636, while the amounts were from 0.4204-3.3636 in low-level MRSA strains, and 0.0718-16.0000 in high-level MRSA strains. There were no difference in the level of femB among MSSA, high-level MRSA and low-level MRSA. CONCLUSION: The expression level of femB may not be related to the resistance of non-beta-lactamase-producting Staphylococcus aureus to methicillin.


Asunto(s)
Proteínas Bacterianas/metabolismo , Farmacorresistencia Microbiana/genética , Staphylococcus aureus Resistente a Meticilina/genética , Oxacilina/farmacología , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Secuencia de Bases , Staphylococcus aureus Resistente a Meticilina/metabolismo , Datos de Secuencia Molecular , Fenotipo , beta-Lactamasas/metabolismo
7.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 42(2): 241-4, 259, 2011 Mar.
Artículo en Zh | MEDLINE | ID: mdl-21500563

RESUMEN

OBJECTIVE: To investigate the prevalence of genes encoding 16S rRNA methylase and the spreading path of these genes in 374 clinical isolate of enterobacteriaceae. METHODS: The genes encoding 16S rRNA methylase in 374 clinical isolate of enterobacteriaceae was detected with PCR. The sequence homogeny analyses were carried out with the NCBL BLAST program and enterbacterial repetitive intergenic consensus PCR (ERIC-PCR). The conjugation experiments were used to determine the transference of 16S rRNA methylase in vitro. RESULTS: In 374 clinical isolates, methylase genes were detected in 24 strains (6.41%), including 10 armA gene positive strains and 10 rmtB gene positive strains, and 4 strains with both genes positive. Highly homogenous strains were confirmed by ERIC-PCR. 45.8% (11/24) of the conjunction experiments for these strains were positive. CONCLUSION: The aminoglycoside resistance in enterobacteriaceae was concerned related to 16S rRNA methylase. The 16S rRNA methylase transferred either by clone or by plasmids horizontal spreading.


Asunto(s)
Enterobacteriaceae/genética , Metiltransferasas/genética , Técnicas de Tipificación Bacteriana , Enterobacteriaceae/clasificación , Enterobacteriaceae/aislamiento & purificación , Infecciones por Enterobacteriaceae/microbiología , Humanos , Homología de Secuencia de Aminoácido
8.
Sci Total Environ ; 750: 141415, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-32846251

RESUMEN

Antibiotics treatment could cause the dysbiosis of human intestinal microbiota and antibiotic resistome. Fecal microbiota transplantation (FMT) has been an efficacious treatment to restore the dysbiosis of intestinal microbiota in a variety of intestinal diseases. However, to data, the effect of the combinatorial antibiotic treatment on microbiota, antibiotic resistome and the FMT for restoration affected by combinatorial antibiotic exposure in the human intestinal microbiota remain unclear. In this study, we systematically investigated the effect of the colistin and amoxicillin combinatorial exposure in the simulator of the human intestinal microbial ecosystem (SHIME) and found that this combinatorial exposure significantly altered (p < 0.05) the human intestinal microbiota and antibiotic resistome. The shift of bacterial community and antibiotic resistome could incompletely recovery to baseline by FMT treatment after combinatorial antibiotic exposure. Additionally, the variance of antibiotic resistome was dominantly driven by the bacterial community (41.18%-68.03%) after the combinatorial antibiotic exposure. Overall, this study first to investigate the influence of the colistin and amoxicillin combinatorial exposure on the intestinal microbiota and antibiotic resistome, and assess the FMT recovery in the simulated human intestinal microbiota, which may potentially provide a correct administration of antibiotics and application of FMT in the clinic.


Asunto(s)
Colistina , Microbioma Gastrointestinal , Amoxicilina , Antibacterianos , Disbiosis , Humanos
9.
Bioengineered ; 12(1): 7714-7723, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34617877

RESUMEN

Osteoporosis (OP) is a systemic bone metabolic disease. Promotion of osteoblast proliferation and inhibition of cell apoptosis may be helpful for the prevention and clinical treatment of OP. In the current study, we focused on the expression changes and clinical values of lncRNA ROR and miR-145-5p in OP clinical serum samples, and investigated the interactive modulation effect of ROR/miR-145-5p on osteoblast function. Serum samples were obtained from 82 OP patients and 79 healthy individuals. MC3T3-E1 was applied for the cell experiments. Levels of lncRNA ROR and miR-145-5p were detected using qRT-PCR. Transient transfection was performed to regulate gene levels in cells, and cell proliferation and apoptosis were detected. A reciprocal correlation between lncRNA ROR and miR-145-5p was explored. LncRNA ROR was downregulated, and miR-145-5p was overexpressed in OP patients. The combined diagnosis of ROR and miR-145-5p showed good diagnostic value for OP. ROR knockdown promoted the MC3T3-E1 cell apoptosis and inhibited cell proliferation. Luciferase reporting assay verified the target relationship between ROR and miR-145-5p. MiR-145-5p downregulation reversed ROR silence mediated effect on MC3T3-E1 cell proliferation and apoptosis. LncRNA ROR is downregulated and miR-145-5p is highly expressed in OP patients. ROR knockdown may inhibit osteoblast proliferation via targeting miR-145-5p. It may provide a theoretical basis and experimental basis for ROR to be a potential target for the treatment of OP.


Asunto(s)
MicroARNs/genética , Osteoblastos/metabolismo , Osteoporosis , ARN Largo no Codificante/genética , Apoptosis/genética , Proliferación Celular/genética , Femenino , Humanos , Masculino , MicroARNs/metabolismo , Persona de Mediana Edad , Osteoporosis/genética , Osteoporosis/metabolismo , Osteoporosis/patología , ARN Largo no Codificante/metabolismo , Transducción de Señal/genética
10.
J Chromatogr Sci ; 59(3): 246-261, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33306786

RESUMEN

This research explored the HPLC fingerprints of Hypericum attenuatum Choisy, which has anti-arrhythmic activity. HPLC was adopted to perform a determination of chemical fingerprints of H. attenuatum specimens acquired through seven distinct sources. The anti-arrhythmic activity of each H. attenuatum sample was obtained through pharmacodynamics experiments in animals. A regression analysis and correlation analysis were utilized to calculate the relationship of the peak and pharmacological effectiveness with the identified peak. Peaks numbered 5, 7, 13 and 14 in the fingerprint were regarded as the likely anti-arrhythmic agents. The fingerprint was compared with reference standards for identification of the correlative peaks. Liquid chromatography-time-of-flight-mass spectrometry was applied to identify its structure. As a consequence, a universal model was established for the utilization of HPLC to investigate anti-arrhythmic activity and the spectrum-effect relationship among H. attenuatum. This model is available for the discovery of the major bioactive constituents of Hypericum.


Asunto(s)
Antiarrítmicos/análisis , Cromatografía Líquida de Alta Presión/métodos , Descubrimiento de Drogas/métodos , Flavonoides/análisis , Hypericum/química , Antiarrítmicos/química , Flavonoides/química , Espectrometría de Masas/métodos , Extractos Vegetales/química
11.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 40(2): 272-4, 278, 2009 Mar.
Artículo en Zh | MEDLINE | ID: mdl-19462905

RESUMEN

OBJECTIVE: To determine the association of the antibiotic resistance of clinical isolates of Acinetobacter baumannii and the genotype of OXA-carbapenemases. METHODS: One hundred and twenty Acinetobacter baumannii strains were isolated from clinical specimens in the West China Hospital from January 2005 to June 2006. The MICs of 12 common antimicrobial agents were determined by 2-fold agar dilution method followed by NCCLS recommendations. The bla(OXA-23) and bla(OXA-24) of those with resistance to IMP were amplified by PCR. RESULTS: The resistant rates of the 120 isolates to 11 common antimicrobial agents exceeded 50% except for IMP (44.4%). One hundred and ten strains were resistant to more than three common antimicrobial agents, with a resistant rate of 91.67%. Of the 50 strains resistant to IMP, 13 stains carried bla(OXA-23). No bla(OXA-24) was found in the resistant isolates. CONCLUSION: Multiple antibiotic resistances are common in Acinetobacters baumannii isolated in the West China Hospital. OXA-23-type carbapenemase is the major carbapenemase that contributes to the nosocomial infection of Acinetobacters baumannii.


Asunto(s)
Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/enzimología , Proteínas Bacterianas/genética , Farmacorresistencia Bacteriana Múltiple/genética , beta-Lactamasas/genética , Antibacterianos/farmacología , Genotipo
12.
Biomed Pharmacother ; 109: 716-725, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30551524

RESUMEN

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor-in-Chief. Features appear similar within the panel "Hypoxia" from Figure 1B, as well as to features from the panel "Hypoxia" of Figure 3C. Also, a section of panel "Hypoxia+pcDNA3.1" from Figure 3D appear similar to sections of the panels "Hypoxia+shNC" and "Hypoxia+sh-RMRP". A section of the "Control" panel of Figure 3D appears similar to sections of panels from Figures 5E-F of the article published by Shenfa Zhuang, Fengxian Liu and Pingping Wu in the Journal of Cellular Biochemistry 120 (2019) 13392-13402 https://doi.org/10.1002/jcb.28614 and Figure 5G of the article published by Yonghui Zhang, Jing Fang, Hongmeng Zhao, Yue Yu, Xuchen Cao and Bin Zhang in the Journal of Cellular Biochemistry 120 (2019) 5097-5107 https://doi.org/10.1002/jcb.27786. Another section of the "Control" panel of Figure 3D appears similar to a section of the panel "miR-1469 inhibitor" from Figure 5F of the article published by the Journal of Cellular Biochemistry 120 (2019) 5097. Given the comments of Dr Elisabeth Bik regarding this article "This paper belongs to a set of over 400 papers (as per February 2020) that share very similar Western blots with tadpole-like shaped bands, the same background pattern, and striking similarities in title structures, paper layout, bar graph design, and - in a subset - flow cytometry panels", the journal requested the authors to provide the raw data. However, the authors were not able to fulfil this request.


Asunto(s)
Proteínas Relacionadas con la Autofagia/biosíntesis , MicroARNs/metabolismo , Daño por Reperfusión Miocárdica/metabolismo , Péptido Sintasas/biosíntesis , ARN Largo no Codificante/biosíntesis , Regulación hacia Arriba/fisiología , Animales , Proteínas Relacionadas con la Autofagia/genética , Línea Celular , Expresión Génica , Marcación de Gen/métodos , Masculino , MicroARNs/genética , Daño por Reperfusión Miocárdica/genética , Péptido Sintasas/genética , ARN Largo no Codificante/genética , Ratas , Ratas Sprague-Dawley
13.
Sheng Wu Gong Cheng Xue Bao ; 34(8): 1259-1269, 2018 Aug 25.
Artículo en Zh | MEDLINE | ID: mdl-30152211

RESUMEN

Overuse of antibiotics in aquaculture, husbandry and healthcare has led to antibiotics residues in the enviuronment and the generation of antibiotic resistant bacteria that can be transferred into the human gut through food chain. Based on literatures, we reviewed the influence of bacterial resistance on intestinal flora and related immune regulation. Taking the source of antibiotic resistance to human intestinal flora as an entry point, we addressed the structure of human intestinal flora and the composition of drug resistance genes after exposure to pollutants. Moreover, we discussed the relationship among changes of intestinal flora, antibiotic resistance genes and immunomodulation related diseases. Last, we also indicated future research needs.


Asunto(s)
Bacterias/efectos de los fármacos , Farmacorresistencia Bacteriana/genética , Microbioma Gastrointestinal , Antibacterianos/farmacología , Bacterias/genética , Humanos
14.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 38(2): 268-71, 2007 Mar.
Artículo en Zh | MEDLINE | ID: mdl-17441346

RESUMEN

OBJECTIVE: To detect the expression level of femA of Staphylococcus aureus strains with different phenotype. METHODS: 15 strains of the non-beta-lactamase-producing clinical isolates with different phenotype by agar dilution and by nitrocephin paper strip method were chosen as the object of test, in addition to 4 donative strains (BB270, BB308, BB586, COL). Total RNA were extracted and analysed by agarose gel electrophoresis. Real time fluorescent quantitative PCR was performed to quantify the expression of femA gene. The expression level of femA of BB270 was set to be standard(100%). RESULTS: The expressions of femA were observed in all the tested strains. The amount of femA-specific mRNA in the mutant strain BB308 was approximately 37.82% and that of stain BB586 was 240.50%, homogeneous resistant strain COL was 862.61%. The amounts in MSSA strains were from 0.00353% to 29.92%, that in low-level MRSA strains were from 0.00554% to 310%, otherwise that in high-level MRSA strains were from 13.88% to 55000%, which were different among these groups. There was no significant difference in amount of femA-mRNA between MSSA and low-level MRSA strains (P1 = 0.83) but marked between high-level MRSA and low-level MRSA/MSSA strains (P2 = 0.006, P3 = 0.01)). CONCLUSION: Expression level of femA in high-level MRSA was significant higher than that in low-level MRSA and MSSA. femA was essential for the expression of high-level methicillin resistance in MRSA.


Asunto(s)
Proteínas Bacterianas/genética , Regulación Bacteriana de la Expresión Génica , Resistencia a la Meticilina/genética , Fenotipo , Staphylococcus aureus/genética , Staphylococcus aureus/fisiología , Girasa de ADN/genética , Reacción en Cadena de la Polimerasa
16.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 37(3): 365-8, 2006 May.
Artículo en Zh | MEDLINE | ID: mdl-16761409

RESUMEN

OBJECTIVE: To inquire into the mechanism of drug resistance in Staphylococcus aureus. METHODS: A total of 198 strains of Staphylococcus aureus were isolated from the samples sent to the Clinical Laboratory of Microbiology,West China Hospital. The resistance of Staphylococcus aureus to Methicillin was assayed with agar dilution. Staphylococcus aureus mecA gene was measured by PCR assay and beta-lactamase was detected by Nitrocephin. RESULTS: The rate of resistance to methicillin was 64.65% in 198 strains of Staphylococcus aureus; 118 strains of methicillin-resistant staphylococcus aureus(MRSA) were found to have high level resistance in 128 MRSA;10 strains of MRSA were found to have low level resistance; 41(58.57%) strains of methicillin-sensitive Staphylococcus aureus (MSSA) expressed beta-lactamase; 2 Staphylococcus aureus had mecA among them; 67 Staphylococcus aureus expressed beta-lactamase in high level resistance, 63(53.39%)Staphylococcus aureus expressed beta-lactamase in high level resistance, among them, 5 Staphylococcus aureus had mecA; 40.00% MRSA expressed beta-lactamase in low level resistance, 55 MRSA did not express beta-lactamase in high level resistance, which had all mecA; 9 Staphylococcus aureus did not express beta-lactamase in low level resistance, among them, 5 Staphylococcus aureus had mecA. The difference in expression of beta-lactamase was statistically significant between MSSA and MRSA; MRSA(53.39%) was lower than MSSA (58.57%); the other differences were not significant. The difference in having mecA was statistically significant between MRSA(having high resistant level and no expression of beta-lactamase) and the others; MRSA had higher mecA than did the others. CONCLUSION: The resistance in Staphylococcus aureus mainly involved two mechanisms: the expression of beta-lactamase and the expression of mecA.


Asunto(s)
Resistencia a la Meticilina/genética , Staphylococcus aureus/efectos de los fármacos , Proteínas Bacterianas/biosíntesis , Proteínas Bacterianas/genética , China , Genes Bacterianos/genética , Humanos , Proteínas de Unión a las Penicilinas , Staphylococcus aureus/enzimología , Staphylococcus aureus/genética , beta-Lactamasas/biosíntesis , beta-Lactamasas/genética
17.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 35(1): 91-3, 2004 Jan.
Artículo en Zh | MEDLINE | ID: mdl-14981826

RESUMEN

OBJECTIVE: To survey the antibiotic resistance of Stenotrophomonas maltophilia in Chengdu and Chongqing area and guide the rational antibiotics usage in the treatment of Stenotrophomonas maltophilia infection. METHODS: Minimal inhibitory concentrations (MICs) of 9 antibiotics against Stenotrophomonas maltophilia were measured using two-fold agar dilution method. RESULTS: A total of 154 strains of Stenotrophomonas maltophilia are multi-drug resistant. But the resistant ratios of trimethoprim-sulfamethoxazole, ticarcillin-clavavulanic acid and fluoroquinolones are lower; especially, new fluoroquinolones have stronger antimicrobial activities. CONCLUSION: The rate of isolating Stenotrophomonas maltophilia strains from clinical samples has been rising. In the therapy of Stenotrophomonas maltophilia infection, trimethoprim-sulfamethoxazole or fluoroquinolones is empirically the medicine of choice. For the treatment of serious infection, the administration of trimethoprim-sulfamethoxazole combined with ticarcillin-clavavulanic acid or new fluoroquinolones is rational.


Asunto(s)
Antiinfecciosos/farmacología , Fluoroquinolonas/farmacología , Stenotrophomonas maltophilia/efectos de los fármacos , Ticarcilina/farmacología , Combinación Trimetoprim y Sulfametoxazol/farmacología , Ácido Clavulánico/farmacología , Farmacorresistencia Bacteriana Múltiple , Humanos , Pruebas de Sensibilidad Microbiana
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