Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
1.
Nutrients ; 15(9)2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37432323

RESUMEN

Depression is the most common mental illnesses worldwide. The consumption of ultra-processed food (UPF) has increased globally due to its affordability and convenience; however, only a few studies have investigated the link between UPF intake and depression in the general population. We investigated the associations between UPF and depression using the Korea National Health and Nutrition Examination Survey. A total of 9463 individuals (4200 males and 5263 females) aged above 19 years old participated in this study. The prevalence of depression was identified using the Patient Health Questionnaire-9. Dietary intake was assessed through a 24-h recall interview. The percentage of energy from UPFs was ascertained based on the NOVA classification. The associations between the quartile ranges of UPF intake and depression were estimated using logistic regression models. Individuals in the highest quartile had a 1.40 times higher likelihood of having depression, with marginal significance (95% confidence intervals (CIs) = 1.00-1.96). In a sex-specific stratification, only females demonstrated a significant association (odds ratio (OR) = 1.51, 95% CI 1.04-2.21), even after adjusting for confounders (p-value for trend = 0.023). Our findings revealed a significant association between higher UPF intake and depression among females but not among males in the Korean general population.


Asunto(s)
Depresión , Alimentos Procesados , Adulto , Femenino , Humanos , Masculino , Adulto Joven , Depresión/epidemiología , Encuestas Nutricionales , República de Corea/epidemiología , Pueblos del Este de Asia
2.
BMC Nephrol ; 23(1): 98, 2022 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-35260104

RESUMEN

BACKGROUND: Chronic stimulation of the mineralocorticoid receptor has been suggested as one of the potential causes of cardiovascular events and death in patients with end-stage renal disease. This observational cohort study was performed to demonstrate that serum cortisol might be a predictive marker for patient mortality and to evaluate its association with oxidized low-density lipoprotein (oxLDL) in hemodialysis (HD) patients. METHODS: Patients receiving HD three times a week were screened for enrollment at two institutions. Baseline cortisol levels were measured before each HD session, and the patients were divided into two groups according to the median value of serum cortisol before analysis. The baseline characteristics and laboratory values of the high and low cortisol groups were compared. Serum cortisol, adrenocorticotropic hormone, renin, aldosterone, and oxLDL were measured in 52 patients to evaluate the effect of oxidative stress on serum cortisol levels. RESULTS: A total of 133 HD patients were enrolled in this cohort study. Compared to the patients with low serum cortisol levels, the patients with high serum cortisol levels (baseline cortisol ≥ 10 µg/dL) showed higher rates of cardiovascular disease (59.7% vs. 39.4%, P=0.019) and left ventricular systolic dysfunction (LVSD) (25.9% vs. 8.0%, P=0.016). The patients in the high cortisol group demonstrated higher all-cause mortality than those in the low cortisol group. The serum cortisol level was an independent risk factor for patient mortality (hazard ratio 1.234, 95% confidence interval 1.022-1.49, P=0.029). Among the 52 patients with oxLDL measurements, oxLDL was an independent risk factor for elevated serum cortisol levels (Exp(B) 1.114, P=0.013) and LVSD (Exp(B) 12.308, P=0.045). However, plasma aldosterone levels did not affect serum cortisol levels. CONCLUSIONS: Serum cortisol is a useful predictive marker for all-cause death among patients receiving HD. OxLDL is an independent marker for elevated serum cortisol among HD patients.


Asunto(s)
Hidrocortisona , Fallo Renal Crónico , Aldosterona , Biomarcadores , Estudios de Cohortes , Femenino , Humanos , Fallo Renal Crónico/complicaciones , Masculino , Estrés Oxidativo , Diálisis Renal
3.
Diagn Pathol ; 16(1): 19, 2021 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-33706755

RESUMEN

BACKGROUND: Immunohistochemistry (IHC) remains the gold standard for the diagnosis of pathological diseases. This technique has been supporting pathologists in making precise decisions regarding differential diagnosis and subtyping, and in creating personalized treatment plans. However, the interpretation of IHC results presents challenges in complicated cases. Furthermore, rapidly increasing amounts of IHC data are making it even harder for pathologists to reach to definitive conclusions. METHODS: We developed ImmunoGenius, a machine-learning-based expert system for the pathologist, to support the diagnosis of tumors of unknown origin. Based on Bayesian theorem, the most probable diagnoses can be drawn by calculating the probabilities of the IHC results in each disease. We prepared IHC profile data of 584 antibodies in 2009 neoplasms based on the relevant textbooks. We developed the reactive native mobile application for iOS and Android platform that can provide 10 most possible differential diagnoses based on the IHC input. RESULTS: We trained the software using 562 real case data, validated it with 382 case data, tested it with 164 case data and compared the precision hit rate. Precision hit rate was 78.5, 78.0 and 89.0% in training, validation and test dataset respectively. Which showed no significant difference. The main reason for discordant precision was lack of disease-specific IHC markers and overlapping IHC profiles observed in similar diseases. CONCLUSION: The results of this study showed a potential that the machine-learning algorithm based expert system can support the pathologic diagnosis by providing second opinion on IHC interpretation based on IHC database. Incorporation with contextual data including the clinical and histological findings might be required to elaborate the system in the future.


Asunto(s)
Inmunohistoquímica , Aprendizaje Automático , Neoplasias/diagnóstico , Neoplasias/patología , Algoritmos , Teorema de Bayes , Sistemas Especialistas , Humanos , Inmunohistoquímica/métodos , Neoplasias/metabolismo , Programas Informáticos
4.
Sci Rep ; 9(1): 9976, 2019 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-31292469

RESUMEN

This paper presents very large complete band gaps at low audible frequency ranges tailored by gradient-based design optimizations of periodic two- and three-dimensional lattices. From the given various lattice topologies, we proceed to create and enlarge band gap properties through controlling neutral axis configuration and cross-section thickness of beam structures, while retaining the periodicity and size of the unit cell. Beam neutral axis configuration and cross-section thickness are parameterized by higher order B-spline basis functions within the isogeometric analysis framework, and controlled by an optimization algorithm using adjoint sensitivity. Our optimal curved designs show much more enhanced wave attenuation properties at audible low frequency region than previously reported straight or simple undulated geometries. Results of harmonic response analyses of beam structures consisting of a number of unit cells demonstrate the validity of the optimal designs. A plane wave propagation in infinite periodic lattice is analyzed within a unit cell using the Bloch periodic boundary condition.

5.
PLoS One ; 14(5): e0216415, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31048884

RESUMEN

BACKGROUND AND AIMS: Malnutrition and inflammation are closely linked to vascular calcification (VC), the severity of which correlate with adverse outcome. However, there were few studies on the interplay between malnutrition, inflammation and VC progression, rather than VC presence per se. We aimed to determine the relationship of malnutrition, inflammation, abdominal aortic calcification (AAC) progression with survival in hemodialysis (HD) patients. METHODS: Malnutrition and inflammation were defined as low serum albumin (< 40 g/L) and high hs-CRP (≥ 28.57 nmol/L), respectively. We defined AAC progression as an increase in AAC score using lateral lumbar radiography at both baseline and one year later. Patients were followed up to investigate the impact of AAC progression on all-cause and cardiovascular mortality. RESULTS: AAC progressed in 54.6% of 97 patients (mean age 58.2±11.7 years, 41.2% men) at 1-year follow-up. Hypoalbuminemia (Odds ratio 3.296; 95% confidence interval 1.178-9.222), hs-CRP (1.561; 1.038-2.348), low LDL-cholesterol (0.976; 0.955-0.996), and the presence of baseline AAC (10.136; 3.173-32.386) were significant risk factors for AAC progression. During the mean follow-up period of 5.9 years, 38(39.2%) patients died and 27(71.0%) of them died of cardiovascular disease. Multivariate Cox regression analysis adjusted for old age, diabetes, cardiovascular history, and hypoalbuminemia determined that AAC progression was an independent predictor of all-cause mortality (2.294; 1.054-4.994). CONCLUSIONS: Malnutrition and inflammation were significantly associated with AAC progression. AAC progression is more informative than AAC presence at a given time-point as a predictor of all-cause mortality in patients on maintenance HD.


Asunto(s)
Aorta Abdominal/diagnóstico por imagen , Desnutrición , Diálisis Renal , Calcificación Vascular , Adulto , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Inflamación/diagnóstico por imagen , Inflamación/mortalidad , Inflamación/terapia , Masculino , Desnutrición/complicaciones , Desnutrición/diagnóstico por imagen , Desnutrición/mortalidad , Desnutrición/terapia , Persona de Mediana Edad , Estudios Prospectivos , Tasa de Supervivencia , Calcificación Vascular/diagnóstico por imagen , Calcificación Vascular/etiología , Calcificación Vascular/mortalidad , Calcificación Vascular/terapia
6.
Artif Cells Nanomed Biotechnol ; 46(sup2): 1127-1136, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30047294

RESUMEN

Due to its tentacle poison and huge body, giant jellyfish (Nemopilema nomurai) poses challenging issues to the environment and ecosystems. Here we developed, upcycling a giant jellyfish extract as a reducing agent, a green synthetic method of gold nanoparticles (JF-AuNPs) which possess biological activities. The colloidal solutions of JF-AuNPs were blue, violet, purple and pink depending on the extract concentration. UV-visible spectra exhibited two surface plasmon resonance bands at 5 4 0 ∼ 550 nm and 810 nm. Spherical shapes with an average size of 35.2 ± 8.7 nm and triangular nanoplates with an average height of 70.5 ± 30.3 nm were observed. A face-centered cubic structure was confirmed by high-resolution X-ray diffraction. JF-AuNPs exhibited significant cytotoxic effect against HeLa cancer cells but not against normal cells such as NIH-3T3 and Raw 264.7 cells. In HeLa cells, JF-AuNPs decreased the phosphorylation of AKT and ERK, which are crucial for cell proliferation. Also, JF-AuNPs decreased NO secretion and iNOS expression levels, resulting in anti-inflammatory effects in LPS-inflamed macrophages. Collectively, we established a green synthesis of anti-tumorigenic and anti-inflammatory JF-AuNPs using the extract of jellyfish sea wastes. Thus, beneficial effects of JF-AgNPs must be weighed in further studies in vivo and it can be potent nanomedicine for future applications.


Asunto(s)
Oro/química , Oro/farmacología , Nanopartículas del Metal/química , Sustancias Reductoras/química , Escifozoos/química , Residuos , Animales , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Tecnología Química Verde , Humanos , Ratones , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo
7.
PLoS One ; 12(10): e0185846, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29049308

RESUMEN

BACKGROUND: Vascular calcification is associated with structural and functional abnormality of the heart and blood vessels. We investigated the relationship between intradialytic hypotension (IDH) and vascular calcification in hemodialysis (HD) patients, and their impacts on cardiovascular events (CVEs). METHOD: We enrolled 191 maintenance HD patients who underwent plain abdomen radiography for abdominal aortic calcification score (AACS). A nadir systolic blood pressure (BP) < 90 mm Hg or the requirement of bolus fluid administration was required to quantify the hypotension diagnosis. IDH was defined as > 2 hypotension episodes during 10 HD treatments. RESULTS: Among the 191 patients, IDH occurred in 32. AACS was higher in the IDH group compared with the no-IDH group (8.4 ± 6.0 vs. 4.9 ± 5.2, respectively; P = 0.001). High AACS was an independent risk factor after adjustment for age, diabetes mellitus, ultrafiltration, diastolic BP, and calcium level (odds ratio (OR) = 1.09, 95% CI = 1.01-1.18; P = 0.03). Patients with both IDH and AACS ≧ 4 had the highest cumulative CVE rate (27.9%, P = 0.008) compared with 11.2%, 12.5%, and 6% for those with AACS ≧ 4 only, with IDH only, and neither, respectively. In multivariate analysis, the presence of both IDH and AACS ≧ 4 was a significant predictor of CVE (hazard ratio (HR) = 2.84, 95% CI = 1.04-7.74, P = 0.04). CONCLUSION: IDH is associated with abdominal aortic calcification and is an independent risk factor for IDH. Both IDH and high AACS were significant predictors of CVE.


Asunto(s)
Hipotensión/complicaciones , Diálisis Renal , Calcificación Vascular/complicaciones , Anciano , Aorta/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad
8.
PLoS One ; 12(9): e0185296, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28953969

RESUMEN

BACKGROUND: Vascular calcification is common and may affect cardiac function in patients with end-stage renal disease (ESRD). However, little is known about the effect of residual renal function on vascular calcification and cardiac function in patients on hemodialysis. METHODS: This study was conducted between January 2014 and January 2017. One hundred six patients with residual renal function on maintenance hemodialysis for 3 months were recruited. We used residual renal urea clearance (KRU) to measure residual renal function. First, abdominal aortic calcification score (AACS) and brachial-ankle pulse wave velocity (baPWV) were measured in patients on hemodialysis. Second, we performed echocardiography and investigated new cardiovascular events after study enrollment. RESULTS: The median KRU was 0.9 (0.3-2.5) mL/min/1.73m2. AACS (4.0 [1.0-10.0] vs. 3.0 [0.0-8.0], p = 0.05) and baPWV (1836.1 ± 250.4 vs. 1676.8 ± 311.0 cm/s, p = 0.01) were significantly higher in patients with a KRU < 0.9 mL/min/1.73m2 than a KRU ≥ 0.9 mL/min/1.73m2. Log-KRU significantly negatively correlated with log-AACS (ß = -0.29, p = 0.002) and baPWV (ß = -0.19, P = 0.05) after factor adjustment. The proportion of left ventricular diastolic dysfunction was significantly higher in patients with a KRU < 0.9 mL/min/1.73m2 than with a KRU ≥ 0.9 mL/min/1.73m2 (67.9% vs. 49.1%, p = 0.05). Patients with a KRU < 0.9 mL/min/1.73m2 showed a higher tendency of cumulative cardiovascular events compared to those with a KRU ≥ 0.9 ml/min/1.73m2 (P = 0.08). CONCLUSIONS: Residual renal function was significantly associated with vascular calcification and left ventricular diastolic dysfunction in patients on hemodialysis.


Asunto(s)
Pruebas de Función Cardíaca , Pruebas de Función Renal , Riñón/fisiopatología , Diálisis Renal , Micción/fisiología , Calcificación Vascular/fisiopatología , Índice Tobillo Braquial , Aorta Abdominal/patología , Aorta Abdominal/fisiopatología , Demografía , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis de la Onda del Pulso , Urea/metabolismo , Calcificación Vascular/diagnóstico por imagen
9.
PLoS One ; 12(1): e0170272, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28099511

RESUMEN

BACKGROUND: In hemodialysis patients, fluid overload and malnutrition are accompanied by extracellular fluid (ECF) expansion and intracellular fluid (ICF) depletion, respectively. We investigated the relationship between ECF/ICF ratio (as an integrated marker reflecting both fluid overload and malnutrition) and survival and cardiovascular disease (CVD) in the context of malnutrition-inflammation-arteriosclerosis (MIA) complex. METHODS: Seventy-seven patients from a single hemodialysis unit were prospectively enrolled. The ECF/ICF volume was measured by segmental multi-frequency bioimpedance analysis. MIA and volume status were measured by serum albumin, C-reactive protein (CRP), pulse wave velocity (PWV) and plasma B-type natriuretic peptide (BNP), respectively. RESULTS: The mean ECF/ICF ratio was 0.56±0.06 and the cut-off value for maximum discrimination of survival was 0.57. Compared with the low ECF/ICF group, the high ECF/ICF group (ratio≥0.57, 42%) had higher all-cause mortality, CVD, CRP, PWV, and BNP, but lower serum albumin. During the 5-year follow-up, 24 all-cause mortality and 38 CVD occurred (18 and 24, respectively, in the high ECF/ICF group versus 6 and 14 respectively in the low ECF/ICF group, P<0.001). In the adjusted Cox analysis, the ECF/ICF ratio nullifies the effects of the MIA and volume status on survival and CVD and was an independent predictor of all-cause mortality and CVD: hazard ratio (95% confidence interval); 1.12 (1.01-1.25) and 1.09 (1.01-1.18) for a 0.01 increase in the ECF/ICF ratio. The degree of malnutrition (albumin), inflammation (CRP), arteriosclerosis (PWV), and fluid overload (BNP) were correlated well with the ECF/ICF ratio. CONCLUSIONS: Hemodialysis patients with high ECF/ICF ratio are not only fluid overloaded, but malnourished and have stiff artery with more inflammation. The ECF/ICF ratio is highly related to the MIA complex, and is a major risk indicator for all-cause mortality and CVD.


Asunto(s)
Arteriosclerosis/patología , Líquido Extracelular/metabolismo , Inflamación/patología , Líquido Intracelular/metabolismo , Desnutrición/patología , Diálisis Renal/mortalidad , Proteína C-Reactiva/análisis , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Péptido Natriurético Encefálico/sangre , Estudios Prospectivos , Análisis de la Onda del Pulso , Factores de Riesgo , Albúmina Sérica/análisis
10.
J Biomed Mater Res B Appl Biomater ; 105(7): 2136-2144, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-27417290

RESUMEN

During the last decade, there has been a great advance in the kidney dialysis system by wearable artificial kidney (WAK) system for end-stage renal disease patients. Uremic solute removal and water regeneration system are the most prerequisite for WAK to work properly. In this study, we designed a filtering membrane system by using immobilized urease silk fibroin filter and evaluated its comparative effectiveness with a PVDF filtering system in peritoneal dialysate regeneration system by urea removal efficacy. We evaluated this membrane's characteristic and performances by conducting SEM-EDX analyze, water-binding abilities and porosity test, removal abilities of urea, cytotoxicity assay and enzyme activity assay. Under the condition for optimization of urease, the percentage removal of urea was about 40% and 60% in 50 mg/dL urea solution by urease immobilized PVDF and silk fibroin scaffolds, respectively. The batch experimental result showed that immobilized filter removed more than 50% of urea in 50 mg/dL urea solution. In addition silk fibroin with urease filter removed 90 percent of urea in the peritoneal dialysate after 24 h filtration. We suggest that silk fibroin with urease fixation filter can be used more effectively for peritoneal dialysate regeneration system, which have hydrophilic property and prolonged enzyme activity. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2136-2144, 2017.


Asunto(s)
Enzimas Inmovilizadas/química , Fibroínas/química , Ensayo de Materiales , Diálisis Peritoneal/instrumentación , Ureasa/química , Animales , Ratones , Células 3T3 NIH
11.
J Microbiol Biotechnol ; 26(9): 1620-8, 2016 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-27238937

RESUMEN

In this study, we investigated colistin resistance mechanisms associated with the regulation of the pbgP operon in Klebsiella pneumoniae, using four isogenic pairs of colistin-susceptible strains and their colistin-resistant derivatives and two colistin-resistant clinical isolates. Amino acid sequence alterations of PhoPQ, PmrAB, and MgrB were investigated, and mRNA expression levels of phoQ, pmrB, pmrD, and pbgP were measured using quantitative real-time PCR. The phoQ and pmrB genes were deleted from two colistin-resistant derivatives, 134R and 063R. We found that phoQ, pmrD, and pbgP were significantly upregulated in all colistin-resistant derivatives. However, pmrB was significantly upregulated in only two colistin-resistant derivatives and one clinical strain. pmrB was not overexpressed in the other strains. The minimum inhibitory concentration of colistin was drastically lower in both phoQ- and pmrB-deleted mutants from a colistin-resistant derivative (134R) that was overexpressing phoQ and pmrB. However, colistin susceptibility was restored only in a phoQ-deleted mutant from a colistin-resistant derivative (063R) without overexpression of pmrB. In conclusion, two different regulations of the pbgP operon may associate with the development of colistin-resisant K. pneumoniae.


Asunto(s)
Colistina/farmacología , Farmacorresistencia Bacteriana/genética , Regulación Bacteriana de la Expresión Génica , Genes Bacterianos/genética , Klebsiella pneumoniae , Secuencia de Aminoácidos , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Eliminación de Gen , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Regulación Bacteriana de la Expresión Génica/genética , Humanos , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/genética , Pruebas de Sensibilidad Microbiana , Operón/genética
12.
Appl Microbiol Biotechnol ; 100(5): 2355-65, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26754815

RESUMEN

Tuberculosis (TB) is a major global health problem, and multi-drug-resistant TB (MDR-TB) and extensively drug-resistant TB (XDR-TB) are spreading throughout the world. However, conventional drug susceptibility test (DST) methods, which rely on the detection of the colony formation on a solid medium, require 1-2 months to the result. A rapid and accurate DST is necessary to identify patients with drug-resistant TB and treat them with appropriate drugs. Here, we used microscopic imaging of Mycobacterium tuberculosis (MTB) immobilized in an agarose matrix for a rapid DST. The agarose matrix, which was molded in a microfluidic chip, was inoculated with MTB, and TB drugs in liquid culture medium diffused throughout the agarose to reach the MTB immobilized in the agarose matrix. After the responses of MTB to drugs were tracked with an automated microscopic system, an image-processing program automatically determined the susceptibility and resistance of MTB to specific doses of TB drugs. The automatic DST system was able to assess the drug susceptibility of various drug-resistant clinical TB strains within 9 days with an accuracy comparable to that of conventional method. Our rapid DST method based on microscopic time-lapse imaging greatly reduces the time required for a DST and can be used to rapidly and accurately treat TB patients.


Asunto(s)
Antituberculosos/farmacología , Pruebas de Sensibilidad Microbiana/métodos , Microfluídica/métodos , Microscopía/métodos , Mycobacterium tuberculosis/efectos de los fármacos , Imagen de Lapso de Tiempo/métodos , Automatización de Laboratorios/métodos , Geles , Humanos , Pruebas de Sensibilidad Microbiana/instrumentación , Sefarosa , Factores de Tiempo
13.
Antimicrob Agents Chemother ; 60(1): 609-12, 2016 01.
Artículo en Inglés | MEDLINE | ID: mdl-26459897

RESUMEN

Colistin-resistant mutants were obtained from 17 colistin-susceptible strains of Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Escherichia coli. The stability of colistin resistance in these mutants was investigated. Three of four colistin-resistant P. aeruginosa mutants recovered colistin susceptibility in colistin-free medium; however, colistin-susceptible revertants were obtained from only one strain each of A. baumannii and E. coli. No susceptible revertants were obtained from K. pneumoniae mutants.


Asunto(s)
Acinetobacter baumannii/efectos de los fármacos , Antibacterianos/farmacología , Colistina/farmacología , Farmacorresistencia Bacteriana/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Klebsiella pneumoniae/efectos de los fármacos , Pseudomonas aeruginosa/efectos de los fármacos , Acinetobacter baumannii/genética , Acinetobacter baumannii/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Farmacorresistencia Bacteriana/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Pruebas de Sensibilidad Microbiana , Tasa de Mutación , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
14.
Antimicrob Agents Chemother ; 59(11): 6763-73, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26282408

RESUMEN

In this study, we investigated the effects of colistin resistance on virulence and fitness in hypermucoviscous (HV) Klebsiella pneumoniae sequence type 23 (ST23) strains. Colistin-resistant mutants were developed from three colistin-susceptible HV K. pneumoniae ST23 strains. The lipid A structures of strains were analyzed by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry. Changes in HV were investigated using the string test, and extracellular polysaccharide production was quantified. The expression levels of the phoQ, pmrD, pmrB, pbgP, magA, and p-rmpA2 genes, serum resistance, and biofilm-forming activity were determined. The fitness of colistin-resistant mutants compared to that of the parental strains was examined by determining the competitive index (CI). The colistin-resistant mutants exhibited reduced HV, which was accompanied by decreased formation of capsular polysaccharides (CPS) and reduced expression of genes (magA and p-rmpA2). While there was enhanced expression of pmrD and pbgP in all colistin-resistant derivatives, there were differences in the expression levels of phoQ and pmrB between strains. MALDI-TOF analysis detected the addition of aminoarabinose or palmitate to the lipid A moiety of lipopolysaccharide in the colistin-resistant derivatives. In addition, survival rates in the presence of normal human serum were decreased in the mutant strains, and CI values (0.01 to 0.19) indicated significant fitness defects in the colistin-resistant derivatives compared to the respective parental strains. In hypervirulent HV K. pneumoniae strains, the acquisition of colistin resistance was accompanied by reduced CPS production, impaired virulence, and a significant fitness cost.


Asunto(s)
Antibacterianos/farmacología , Colistina/farmacología , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biopelículas/efectos de los fármacos , Farmacorresistencia Bacteriana/genética , Regulación Bacteriana de la Expresión Génica , Polisacáridos Bacterianos/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
15.
BMC Musculoskelet Disord ; 16: 69, 2015 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-25886842

RESUMEN

BACKGROUND: Since the reference value is the core factor of the T-score calculation, it has a significant impact on the prevalence of osteoporosis. The purpose of this study was to determine the effects of using the Korean reference value on the prevalence of osteoporosis and on the prediction of fracture risk. METHODS: We used femoral neck bone mineral density (BMD) data from the Korea National Health and Nutrition Examination Survey (KNHANES) 2008-2011. The Korean reference was identified by the mean and standard deviation of men and women aged 20-29 years. We compared the prevalence and the fracture risk assessment tool (FRAX™) probability obtained from the Korean reference and the NHANES III reference. RESULTS: In men, the prevalence of osteoporosis increased when using the Korean men's reference, and the difference increased up to 9% for those in their 80s. In women, the prevalence increased when using the NHANES III reference, and the difference increased up to 17% for those in their 80s. The reference value also affected the fracture risk probability, and the difference from changing the reference value increased in women and in subjects with more clinical fracture risk factors. In major osteoporotic fractures, the difference of the risk probability was up to 6% in women aged 70-79 years with two clinical risk factors. For femoral neck fractures, the difference was up to 7% in women aged 50-59 years with two clinical risk factors. CONCLUSIONS: We confirmed that the reference value had significant effects on the prevalence of osteoporosis and on the fracture risk probability. The KNHANES 2008-2011 BMD data reflected the characteristics of the Korean BMD status well with regard to data size and study design; therefore, these data can be used as reference values.


Asunto(s)
Fracturas Óseas/etnología , Fracturas Óseas/epidemiología , Encuestas Nutricionales/normas , Osteoporosis/etnología , Osteoporosis/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Densidad Ósea , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Valor Predictivo de las Pruebas , Prevalencia , Valores de Referencia , República de Corea/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Factores Sexuales
18.
Int J Cardiol ; 176(3): 941-5, 2014 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-25200848

RESUMEN

BACKGROUND: Periprocedural (6 h pre- and 24 h post-angiography) hemofiltration appears to effectively prevent contrast-induced nephropathy (CIN) in chronic kidney disease (CKD) patients undergoing coronary angiography. However, this procedure over-uses medical resources, and the cessation of hemofiltration during coronary angiography results in persistent renal injury. In comparison, simultaneous hemofiltration performed only during coronary angiography requires fewer medical resources and can provide instantaneous protection against CIN. METHODS: Sixty-eight CKD patients (serum creatinine, 2.51±1.15 mg/dL) undergoing coronary angiography were randomized in a 1:2 ratio to receive either periprocedural (n=23) or simultaneous (n=45) hemofiltration. The expected CIN rate was similar for the two groups (41.3% versus 40.0%, p=0.769). RESULTS: On day 3 after contrast exposure, four and seven patients in the periprocedural and simultaneous groups, respectively experienced CIN (17.4% versus 15.6%, p=0.846). On days 5-30, seven and three patients in the periprocedural and simultaneous groups, respectively experienced CIN (30.4% versus 6.7%, p=0.009). The serum creatinine levels of patients in the periprocedural group transiently decreased on day 1 and persistently increased during days 5-30 compared with the simultaneous group. This difference between the two groups in terms of creatinine levels over time was statistically significant (F statistic=6.830; p=0.001, by ANCOVA). The cost of hemofiltration was doubled in the periprocedural group ($1066±83 versus $504±40, p<0.001). CONCLUSIONS: Simultaneous hemofiltration provide equal early (day 3) and better late-stage (days 5-30) renal protection against CIN at a significantly lower cost compared with periprocedural hemofiltration.


Asunto(s)
Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/prevención & control , Medios de Contraste/efectos adversos , Angiografía Coronaria/efectos adversos , Hemofiltración/métodos , Insuficiencia Renal Crónica/diagnóstico por imagen , Lesión Renal Aguda/epidemiología , Anciano , Angiografía Coronaria/métodos , Creatinina/sangre , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Atención Perioperativa/métodos , Proyectos Piloto , Estudios Prospectivos , Insuficiencia Renal Crónica/sangre , Insuficiencia Renal Crónica/complicaciones , Ácidos Triyodobenzoicos/efectos adversos
19.
Nanoscale Res Lett ; 9(1): 103, 2014 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-24589224

RESUMEN

An eco-friendly approach is described for the green synthesis of gold nanoparticles using catechin as a reducing and capping agent. The reaction occurred at room temperature within 1 h without the use of any external energy and an excellent yield (99%) was obtained, as determined by inductively coupled plasma mass spectrometry. Various shapes of gold nanoparticles with an estimated diameter of 16.6 nm were green-synthesized. Notably, the capping of freshly synthesized gold nanoparticles by catechin was clearly visualized with the aid of microscopic techniques, including high-resolution transmission electron microscopy, atomic force microscopy, and field emission scanning electron microscopy. Strong peaks in the X-ray diffraction pattern of the as-prepared gold nanoparticles confirmed their crystalline nature. The catalytic activity of the as-prepared gold nanoparticles was observed in the reduction of 4-nitrophenol to 4-aminophenol in the presence of NaBH4. The results suggest that the newly prepared gold nanoparticles have potential uses in catalysis.

20.
Eur J Drug Metab Pharmacokinet ; 39(1): 11-6, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23749586

RESUMEN

The pharmacokinetic interaction of enrofloxacin and trimethoprim was evaluated after single-dose intraperitoneal or oral co-administration in rats. Plasma concentrations of the two drugs were determined by high-performance liquid chromatography. Following intraperitoneal combination, a significant (P < 0.05) increase in mean values of plasma half-life (t 1/2) and maximum plasma concentration (C max) was observed for enrofloxacin and trimethoprim, respectively. There was a significant (P < 0.05) increase in mean values of area under the plasma drug concentration versus time from time zero to infinity (AUC0-∞) and C max between combined oral doses (10, 30 and 100 mg/kg) of both antibacterial drugs. Also, after oral conjugation a significant difference in mean values of MRT0-∞ was observed between lower (10 mg/kg) and higher (100 mg/kg) doses of both drugs. A significant increase in pharmacokinetic parameters of both drugs in combined intraperitoneal and oral doses indicated pharmacokinetic interaction of enrofloxacin and trimethoprim. Further study is recommended in other species of animals.


Asunto(s)
Antibacterianos/administración & dosificación , Antibacterianos/farmacocinética , Fluoroquinolonas/administración & dosificación , Fluoroquinolonas/farmacocinética , Trimetoprim/administración & dosificación , Trimetoprim/farmacocinética , Administración Oral , Animales , Antibacterianos/sangre , Área Bajo la Curva , Cromatografía Líquida de Alta Presión , Combinación de Medicamentos , Interacciones Farmacológicas , Enrofloxacina , Fluoroquinolonas/sangre , Semivida , Inyecciones Intraperitoneales , Masculino , Tasa de Depuración Metabólica , Ratas , Ratas Sprague-Dawley , Trimetoprim/sangre
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA