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1.
Opt Express ; 29(2): 2884-2892, 2021 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-33726475

RESUMEN

With increasing use of mobile displays outdoors, privacy-related issues have come to the fore. Therefore, in this study, we proposed a novel concept using directionally guided light transmission using double-sided asymmetric prism arrays for fabricating a privacy protection film for digital displays. The proposed film allows only the user in front of the display to see its contents using dual refraction in a prism array. Otherwise, when the display is viewed at an angle, it is difficult to recognize the contents due to the overlap of different letters. The optical path was analysed through ray-tracing simulations, and the performance of the film was quantified using an optical character recognition (OCR) method. To further enhance the effectiveness of the film, a metal film was applied on the vertical face of the micro prism arrays using an oblique deposition method. This metal-coated double-sided prism array film showed superior privacy-protecting performance compared to a conventional method based on the micro-louver structure.

2.
Int Endod J ; 54(3): 377-387, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33090483

RESUMEN

AIM: To examine the type of vesicular glutamate transporter (VGLUT)-immunopositive (+) axons that coexpress neuropeptides in the rat and human dental pulp, which may help understand peripheral mechanism of pulpal inflammatory pain in rats and humans. METHODOLOGY: The trigeminal ganglia (TG) and the dental pulp of the maxillary molar teeth from three male Sprague-Dawley rats weighing 300-330 g and dental pulps of three healthy human (male) maxillary premolar teeth from three 16 to 28-year-old patients extracted for orthodontic treatment were used. The type of VGLUT + axons that coexpress substance P (SP)- and/or calcitonin gene-related peptide (CGRP) and parvalbumin in the rat TG and in the axons of the rat and the human dental pulp was examined by double fluorescence immunohistochemistry and quantitative analysis. Results were analyzed using one-way anova and the Kruskal-Wallis test. RESULTS: SP and CGRP were expressed in many human VGLUT1 + pulpal axons but not in the rat VGLUT1 + TG neurons and pulpal axons (P < 0.05). SP and CGRP were expressed in a considerable number of human VGLUT2 + pulpal axons and also in many rat TG neurons and pulpal axons. The fraction of VGLUT1 + axons expressing parvalbumin was about three times higher in the rat than in the human dental pulp (P < 0.05). CONCLUSIONS: These findings suggest that the types of VGLUT + axons, which release neuropeptides, may be different between the rat and the human dental pulp, raising a possibility that peripheral mechanism of pulpal inflammatory pain may be different between rats and humans.


Asunto(s)
Neuropéptidos , Proteínas de Transporte Vesicular de Glutamato , Animales , Axones , Pulpa Dental , Humanos , Ratas , Ratas Sprague-Dawley
3.
Int Endod J ; 54(7): 1142-1154, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33641170

RESUMEN

AIM: To identify odontogenesis-promoting compounds and examine the molecular mechanism underlying enhanced odontoblast differentiation and tooth formation. METHODOLOGY: Five different nymphaeols, nymphaeol B (NB), isonymphaeol B (INB), nymphaeol A (NA), 3'-geranyl-naringenin (GN) and nymphaeol C (NC) were isolated from the fruit of Macaranga tanarius. The cytotoxic effect of nymphaeols on human DPSCs was observed using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The effect of nymphaeols on odontoblast differentiation was analysed with Alizarin Red S staining and odontoblast marker expression was assessed using real-time polymerase chain reaction and Western blot analysis. The molecular mechanism was investigated with Western blot analysis. In order to examine the effect of INB on dentine formation in the developing tooth germ, INB-soaked beads were placed under the tooth bud explants in the collagen gel; thereafter, the tooth bud explant-bead complexes were implanted into the sub-renal capsules for 3 weeks. Tooth root formation was analysed using micro-computed tomography and histological analysis. Data are presented as mean ± standard error (SEM) values of three independent experiments, and results are compared using a two-tailed Student's t-test. The data were considered to have statistical significance when the P-value was less than 0.05. RESULTS: Three of the compounds, NB, INB, and GN, did not exert a cytotoxic effect on human DPSCs. However, INB was most effective in promoting the deposition of calcium minerals in vitro (P < 0.001) and induced the expression of odontogenic marker genes (P < 0.05). Moreover, this compound strongly induced the phosphorylation of mitogen-activated protein (MAP) kinases and protein kinase B (AKT) (P < 0.05). The inhibition of p38 MAP, c-Jun N-terminal kinase (JNK), and AKT substantially suppressed the INB-induced odontoblast differentiation (P < 0.001). In addition, isonymphaeol B significantly induced the formation of dentine and elongation of the tooth root in vivo (P < 0.05). CONCLUSIONS: Prenylflavonoids, including INB, exerted stimulatory effects on odontoblast differentiation and tooth root and dentine formation via the MAP kinase and AKT signalling pathways. These results suggest that nymphaeols could stimulate the repair processes for dentine defects or injuries.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Euphorbiaceae/química , Flavonoides/farmacología , Odontoblastos/efectos de los fármacos , Células Madre/efectos de los fármacos , Células Cultivadas , Pulpa Dental/citología , Humanos , Proteínas Quinasas Activadas por Mitógenos , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Raíz del Diente , Microtomografía por Rayos X
4.
Cogn Affect Behav Neurosci ; 20(1): 49-58, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31654234

RESUMEN

Weight-associated stigmatization and discrimination may induce chronic stress in individuals with obesity. As a consequence, this stressor may cause an imbalance of HPA stress axis leading to increased eating behavior, and ultimately, weight gain. However, the direct link between internalized weight bias and stress response to acute stressors via cortisol secretion has not been investigated so far. Therefore, the purpose of this study was to investigate the interaction between internalized weight stigma as a stressor and cortisol reactivity in an acute psychosocial stress situation induced by the Trier Socials Stress Test for groups (TSST-G). Participants with BMI >30 kg/m2 (n = 79) were included in the study. Results reveal that while individuals with low internalized stigma reacted as predicted with an increase in cortisol secretion to acute psychosocial stress, individuals with medium or high internalized stigma did not show a typical cortisol response. However, these findings depend on the several factors, for instance on gender. In sum, acute stress in individuals with internalized weight bias seems to blunt HPA axis reactions to acute psychosocial stress. The study contributes to the understanding of the psychological and endocrinological consequences of internalized weight bias and underlines the importance of interventions to reduce stigmatization.


Asunto(s)
Sistema Hipotálamo-Hipofisario/fisiología , Sistema Hipófiso-Suprarrenal/fisiología , Estigma Social , Estrés Psicológico/psicología , Adulto , Peso Corporal/fisiología , Femenino , Humanos , Masculino , Obesidad/fisiopatología
5.
J Intern Med ; 288(6): 689-698, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32583471

RESUMEN

OBJECTIVES: This study aimed to examine the association between statin exposure and dementia risk in individuals with hypercholesterolaemia using data from the NHIS-HEALS database between 2002 and 2015. METHODS: Subjects were classified into statin exposure and statin nonexposure groups according to medication possession ratio. Dementia was defined as those with primary diagnostic dementia codes such as F00-F03, G30, G31.1, G31.9 or G31.82. Cox proportional hazards regression models were adopted after stepwise adjustment for confounders to investigate the prospective association between statin exposure and dementia risk. RESULTS: During the follow-up period (median follow-up 11.7 years), 711 cases of dementia occurred, accounting for 11.5% of the total study population (statin exposure group, 8.2%; statin nonexposure group, 12.9%). Compared to the statin nonexposure group, fully adjusted hazard ratios (HRs) (95% confidence intervals [CIs]) for overall dementia in the statin exposure group were 0.63 (0.43-0.91) and 0.62 (0.50-0.78) in men and women, respectively. Compared to the statin nonexposure group, the HRs (95% CIs) for Alzheimer's disease and related dementia, vascular dementia and other types of dementia in the statin exposure group were 0.54 (0.32-0.91), 2.45 (0.69-8.68) and 0.59 (0.32-1.07), respectively, in men and 0.53 (0.38-0.73), 1.29 (0.42-3.96) and 0.70 (0.51-0.96), respectively, in women. CONCLUSIONS: Hypercholesterolaemic individuals exposed to statin had a lower risk of overall dementia and Alzheimer's disease and related dementia in both sexes, and a lower risk of other types of dementia in women, than subjects who were not exposed to statins.


Asunto(s)
Demencia/epidemiología , Demencia/prevención & control , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Hipercolesterolemia/tratamiento farmacológico , Adulto , Anciano , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Distribución por Sexo
6.
Osteoporos Int ; 31(12): 2363-2372, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32638050

RESUMEN

Intake of plant-based protein and recommended protein intake are associated with a lower risk of osteosarcopenic adiposity (co-occurrence of osteopenia/osteoporosis, sarcopenia, and adiposity) in elderly Korean men. INTRODUCTION: Osteosarcopenic adiposity (OSA) syndrome is defined as the concurrent presence of osteopenia/osteoporosis, sarcopenia, and adiposity and leads to negative functional and metabolic outcomes in late adulthood. This study aimed to investigate the association between OSA and protein intake in adults aged 50 or older. METHODS: A population-based, cross-sectional survey was conducted using the Korea National Health and Nutrition Examination Survey 2008-2009 data and included 645 men and 706 women aged 50 or older. Subjects were classified into normal and OSA groups. Protein intake was analyzed using the 24-h recall method. RESULTS: There was no significant difference in the intake of total protein and animal-based protein between normal and OSA groups. However, in males, the intake of plant-based protein (p = 0.0031) was significantly lower in the OSA group than that in the normal group. Further, the protein intake in the OSA group was 0.96 g/kg/day, which was significantly lower than that in the normal group (1.06 g/kg/day; p = 0.0203). After adjusting for confounding factors, men over 65 years old who consumed less than the recommended nutrient intake (RNI) of 0.91 g/kg/day had 5.82 times higher risk of OSA compared with subjects consuming protein equal to or greater than the RNI amount (95% CI 1.81-18.66). CONCLUSION: In conclusion, a protein intake of RNI or more is associated with a lower risk of OSA in Korean elderly men.


Asunto(s)
Adiposidad , Sarcopenia , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas Nutricionales , Obesidad , República de Corea/epidemiología , Sarcopenia/epidemiología
7.
J Eur Acad Dermatol Venereol ; 34(12): 2907-2913, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32603006

RESUMEN

BACKGROUND: Novel picosecond lasers using a diffractive optical element (P-DOE) have been available for skin resurfacing with distinct mechanisms. However, there are limited data directly comparing P-DOE and conventional fractional lasers for the treatment of atrophic acne scarring. OBJECTIVES: We sought to compare the efficacy and safety of a 1064-nm neodymium-doped yttrium aluminium garnet P-DOE and a non-ablative fractional laser (NAFL) in the treatment of acne scarring. METHODS: A prospective, randomized, split-face, controlled trial was performed. One randomly assigned half-side of each patient's face (n = 25) was treated with four consecutive sessions of P-DOE at 3-week intervals and the other side with NAFL, with subsequent follow-up for 8 weeks after the final sessions. The efficacy and safety of the two lasers were determined by the Echelle d'Evaluation Clinique des Cicatrices d'acné (Scale of Clinical Evaluation of Acne Scars; ECCA) grading scale, Investigator's Global Assessment (IGA) score and patients' reports at the final visit. Histologic analysis was also performed. RESULTS: The P-DOE-treated side achieved a significantly better improvement in acne appearance (ECCA per cent reduction: 55% vs. 42%) with less severe pain (4.3 vs. 5.6) (P < 0.05). The IGA score and subjective satisfaction were consistent with ECCA score results. Occurrences of treatment-related side-effects were also lower in the group treated with P-DOE (P < 0.05). Histologic analysis revealed elongation and increased density of neocollagen fibres, elastic fibres and mucin throughout the dermis from both sides. CONCLUSIONS: Compared with NAFL, P-DOE afforded better clinical outcomes and fewer side-effects in the treatment of acne scarring in Asian patients.


Asunto(s)
Acné Vulgar , Láseres de Estado Sólido , Acné Vulgar/complicaciones , Aluminio , Cicatriz/etiología , Cicatriz/patología , Erbio , Humanos , Láseres de Estado Sólido/uso terapéutico , Neodimio , Satisfacción del Paciente , Estudios Prospectivos , Resultado del Tratamiento , Itrio
8.
J Appl Microbiol ; 124(1): 241-253, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29044827

RESUMEN

AIM: In this study, the effects of the addition of salt to treatment with acids (one of several organic acids and salt in various solutions including rich or minimal broth, buffer, or distilled water) on the reduction of Escherichia coli O157:H7 were investigated. The protein expression profiles corresponding to acid stress (acetic acid) with or without salt addition were studied using a comparative proteomic analysis of E. coli O157:H7. METHODS AND RESULTS: When acetic, lactic, or propionic acid was combined with 3% NaCl, mutually antagonistic effects of acid and salt on viability of E. coli O157:H7 were observed only in tryptone and yeast extract broth. After exposure to acetic acid alone or in combination with salt, approximately 851 and 916 protein spots were detected, respectively. Analysis of 10 statistically significant differentially expressed proteins revealed that these proteins are mainly related to energy metabolism. CONCLUSIONS: When we compared protein expression of E. coli O157:H7 treated with acetic acid and the combination of the acid and salt, the differentially expressed proteins were not related to acid stress- and salt stress-inducible proteins such as stress shock proteins. SIGNIFICANCE AND IMPACT OF THE STUDY: According to these results, the increased resistance of E. coli O157:H7 to acetic acid after the addition of salt may not be the result of synthesis of proteins related to these phenomena; therefore, further research needs to be conducted to identify the mechanism of the mutually antagonistic effect of some organic acids and salt.


Asunto(s)
Ácidos/farmacología , Escherichia coli O157/efectos de los fármacos , Escherichia coli O157/crecimiento & desarrollo , Cloruro de Sodio/farmacología , Antiinfecciosos/farmacología , Recuento de Colonia Microbiana , Escherichia coli O157/genética , Escherichia coli O157/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Concentración de Iones de Hidrógeno , Proteómica
9.
J Eur Acad Dermatol Venereol ; 32(4): 639-644, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29178495

RESUMEN

BACKGROUND: While device-based acne treatments are widely applied for patients not tolerating conventional medications, related controlled studies have been still limited. Recently, non-ablative 1450-nm diode laser (DL) and fractional microneedling radiofrequency (FMR) have been effectively used for acne, in addition to well-recognized dermal remodelling effects. OBJECTIVE: To compare the clinical course of acne treatment between DL and FMR. METHODS: Twenty-five Korean patients with mild-to-moderate facial acne completed treatments with DL and FMR through a 20-week, randomized split-face study. One randomly assigned half side of each patient's face received DL and the other side by FMR. Treatments were scheduled to receive three consecutive sessions at 4-week intervals. Objective assessments including revised Leeds grades, lesion counts, sebum output measurements, and patients' subjective satisfaction were investigated. RESULTS: Both DL and FMR demonstrated steady improvement of acne and seborrhoea during treatment sessions. While results between two devices were similar during treatment sessions, FMR was superior to DL in the 12-week follow-up. Patients' subjective assessments for seborrhoea improvement were similar between two devices, while those for acne, skin texture, and acne scars were more satisfactory for FMR. For safety profile, no significant difference was observed between two regimens, while mild postinflammatory hyperpigmentation was observed only in DL side. CONCLUSION: Both DL and FMR demonstrated efficacies for acne and seborrhoea, with reasonable safety profile. FMR was more effective than DL for the long-term maintenance, and subjective assessments for texture and scar improvements. Therefore, a few sessions of these devices would be a viable option for acne treatments.


Asunto(s)
Acné Vulgar/terapia , Dermatitis Seborreica/terapia , Terapia por Láser/instrumentación , Agujas , Acné Vulgar/patología , Acné Vulgar/radioterapia , Adolescente , Adulto , Dermatitis Seborreica/patología , Dermatitis Seborreica/radioterapia , Femenino , Humanos , Terapia por Láser/efectos adversos , Masculino , Agujas/efectos adversos , Satisfacción del Paciente , Estudios Prospectivos , República de Corea , Sebo/metabolismo , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Adulto Joven
10.
Infect Immun ; 85(12)2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28970272

RESUMEN

Development of approaches to genetically manipulate Chlamydia is fostering important advances in understanding pathogenesis. Fluorescence-reported allelic exchange mutagenesis (FRAEM) now enables the complete deletion of specific genes in C. trachomatis L2. We have leveraged this technology to delete the coding sequences for a known type III effector. The evidence provided here indicates that CT694/CTL0063 is a virulence protein involved in chlamydial invasion. Based on our findings, we designate the gene product corresponding to ct694-ctl0063translocated membrane-associated effector A (TmeA). Deletion of tmeA did not impact development of intracellular chlamydiae. However, the absence of TmeA manifested as a decrease in infectivity in both tissue culture and murine infection models. The in vitro defect was reflected by impaired invasion of host cells. TmeA binds human AHNAK, and we demonstrate here that AHNAK is transiently recruited by invading chlamydiae. TmeA, however, is not required for endogenous AHNAK recruitment. TmeA also impairs AHNAK-dependent actin bundling activity. This TmeA-mediated effect likely does not explain impaired invasion displayed by the tmeA strain of Chlamydia, since AHNAK-deficient cells revealed no invasion phenotype. Overall, our data indicate the efficacy of FRAEM and reveal a role of TmeA during chlamydial invasion that manifests independently of effects on AHNAK.


Asunto(s)
Proteínas Bacterianas/metabolismo , Chlamydia trachomatis/patogenicidad , Marcación de Gen/métodos , Proteínas de la Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Factores de Virulencia/metabolismo , Animales , Proteínas Bacterianas/genética , Células Cultivadas , Infecciones por Chlamydia/patología , Chlamydia trachomatis/genética , Modelos Animales de Enfermedad , Fluorescencia , Humanos , Ratones , Mutagénesis , Recombinación Genética , Análisis de Supervivencia , Factores de Virulencia/genética
11.
J Endocrinol Invest ; 39(11): 1329-1336, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27561910

RESUMEN

PURPOSE: Nonalcoholic fatty liver disease (NAFLD) is associated with various metabolic abnormalities that can increase the risk of an osteoporotic fracture. Across the few previous studies of the association between NAFLD and bone mineral density (BMD), the association was not consistent. We examined the association between BMD and NAFLD in generally healthy adults. METHODS: The subjects who visited the Seoul National University Hospital for health checkup between 2005 and 2015 were included. Men aged more than 40 and postmenopausal women were included. Lumbar spine and femoral neck (FN) BMD were measured using dual-energy X-ray absorptiometry. Liver ultrasonography was conducted to evaluate the extent of fatty changes. After excluding subjects with a secondary cause of liver disease such as heavy drinking or viral hepatitis, multivariable linear regression analysis adjusted for possible cofactors was performed to investigate the association between BMD and NAFLD. RESULTS: A total of 6634 subjects was included in this study (men:women = 3306:3328). Multivariate regression analysis revealed a significant negative association between FN BMD and NAFLD in men (ß = -0.013, p = 0.029). However, there was a positive correlation between lumbar spine BMD and NAFLD in postmenopausal women (ß = 0.022, p = 0.005). CONCLUSIONS: Moderate or severe NAFLD exerted a detrimental effect on FN BMD in men. However, moderate or severe NAFLD had a positive effect on lumbar spine BMD in postmenopausal women. Potential sex-specific differences of the effect of NAFLD on BMD need to be elucidated further.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico/fisiopatología , Osteoporosis/complicaciones , Absorciometría de Fotón , Adulto , Biomarcadores/análisis , Biomarcadores/sangre , Densidad Ósea , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Enfermedad del Hígado Graso no Alcohólico/etiología , Osteoporosis/metabolismo , República de Corea/epidemiología , Factores de Riesgo , Ultrasonografía
13.
Parasitology ; 142(6): 807-15, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25621413

RESUMEN

Trematode tyrosinases (TYRs) play a major role in the tanning process during eggshell formation. We investigated the molecular and biochemical features of Paragonimus westermani TYR (PwTYR). The PwTYR cDNA was composed of 1568-bp encompassing a 1422-bp-long open reading frame (474-amino acid polypeptide). A strong phylogenetic relationship with Platyhelminthes and Deuterostomian orthologues was evident. The recombinant PwTYR expressed in prokaryotic cells promptly oxidized diphenol substrates, with a preferential affinity toward ortho-positioned hydroxyl groups. It demonstrated fairly weak activity for monophenol compounds. Diphenol oxidase activity was augmented with an increase of pH from 5.0 to 8.0, while monophenol oxidase activity was highest at an acidic pH and gradually decreased as pH increased. Transcription profile of PwTYR was temporally upregulated along with worm development. PwTYR was specifically localized in vitellocytes and eggs. The results suggested that conversion of tyrosine to L-dihydroxyphenylalanine by PwTYR monophenol oxidase activity might be rate-limiting step during the sclerotization process of P. westermani eggs. The pH-dependent pattern of monophenol and diphenol oxidase activity further proposes that the initial hydroxylation might slowly but steadily progress in acidic secreted vesicles of vitellocytes and the second oxidation process might be rapidly accelerated by neural or weak alkaline pH environments within the ootype.


Asunto(s)
Regulación Enzimológica de la Expresión Génica/fisiología , Monofenol Monooxigenasa/metabolismo , Paragonimus/enzimología , Secuencia de Aminoácidos , Animales , Clonación Molecular , ADN Complementario , Cáscara de Huevo/enzimología , Datos de Secuencia Molecular , Monofenol Monooxigenasa/genética , Proteínas Recombinantes , Membrana Vitelina/enzimología
14.
J Appl Microbiol ; 119(2): 455-64, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25973744

RESUMEN

AIM: In this study, the effectiveness of combining each of seven types of acids with 3% salt as a treatment against pathogens was investigated in laboratory media and acidified food. METHODS AND RESULTS: When 0.5% malic, 0.5% tartaric, 0.5% citric or 0.25% phosphoric acid was combined with 3% salt, there was a higher reduction in Gram-negative bacteria (Escherichia coli O157:H7 and Salmonella Typhimurium) compared to when using acid alone. However, when 0.5% acetic, 0.5% propionic or 0.25% lactic acid was combined with 3% salt, the salt provided protection against the acid treatment. However, the antagonistic effects of acetic, propionic and lactic acid seen with Gram-negative bacteria were not observed in Listeria monocytogenes. Antagonistic effects were similarly observed when E. coli O157:H7 was treated with acetic acid and salt in food. CONCLUSIONS: These results show that the addition of salt increases the resistance of Gram-negative bacteria to acid treatments when using acetic, propionic and lactic acid. SIGNIFICANCE AND IMPACT OF THE STUDY: This study shows that antagonistic effects were observed when Gram-negative bacteria were treated with organic acids of simple structure. It may provide useful information for understanding the acid resistance mechanism of Gram-negative bacteria and developing methods for preserving acidified food.


Asunto(s)
Ácidos/farmacología , Bacterias/efectos de los fármacos , Conservación de Alimentos/métodos , Cloruro de Sodio/farmacología , Verduras/microbiología , Ácidos/análisis , Bacterias/crecimiento & desarrollo , Bacterias/metabolismo , Medios de Cultivo/química , Medios de Cultivo/metabolismo , Microbiología de Alimentos , Cloruro de Sodio/análisis
15.
J Appl Microbiol ; 117(6): 1700-8, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25178712

RESUMEN

AIMS: This study investigated the effects of sodium chloride (NaCl) and various acids, alone or in combination, on Shigella flexneri growth in laboratory medium and cucumber puree. METHODS AND RESULTS: Shigella flexneri was treated with various acids (acetic, citric, malic, tartaric, propionic, lactic and phosphoric acid) alone or with 3, 6 or 9% NaCl. Pronounced antagonistic effects were observed in Sh. flexneri treated with acetic or lactic acid in combination with 3% NaCl. Next, Sh. flexneri was pre-exposed to 3% NaCl and then treated with various acids; acid-stressed cells were then inoculated onto agar plates containing 3% NaCl. There was no significant difference in the reduction of Sh. flexneri, regardless of treatment (P > 0·05). Finally, Sh. flexneri was inoculated into cucumber puree to which various concentrations of acetic acid had been added with and without 3% NaCl. Antagonistic effects were observed with a treatment of either 0·5 or 1% acetic acid combined with 3% NaCl. CONCLUSIONS: Antagonistic effects were observed when Sh. flexneri was exposed to acetic or lactic acid with NaCl. SIGNIFICANCE AND IMPACT OF THE STUDY: This study shows that depending on the type of acid, the addition of NaCl can increase the resistance of Sh. flexneri to acid treatments. This may provide useful information for developing methods of preserving acidified foods.


Asunto(s)
Shigella flexneri/efectos de los fármacos , Cloruro de Sodio/farmacología , Ácido Acético/farmacología , Ácidos/farmacología , Cucumis sativus , Medios de Cultivo , Concentración de Iones de Hidrógeno , Viabilidad Microbiana/efectos de los fármacos , Shigella flexneri/crecimiento & desarrollo
16.
Plant Dis ; 98(10): 1450, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30703940

RESUMEN

White clover (Trifolium repens L.) is a herbaceous, perennial plant that has become one of the most widely distributed legumes in the world. It is extensively used in grass-legume pastures, but also has the potential to invade agricultural lands and natural ecosystems. White clover is a well-known natural host for Alfalfa mosaic virus (AMV), Clover yellow vein virus (ClYVV), Soybean dwarf virus (SbDV), Beet western virus (BWYV), Tomato spotted wilt virus (TSWV), Zucchini yellow mosaic virus (ZYMV), etc (1). In July 2013, during a survey to determine the presence of different viruses infecting weed plants in South Korea, three white clover leaf samples showing yellow mosaic symptoms were collected from Taean County, South Chungcheong Do Province, South Korea. In order to identify the infecting virus, total RNA from three leaf samples was extracted using the Tri-reagent (MRC Reagent, Inc., OH) as described by the manufacturer, and was applied to the large-scale oligonucleotide (LSON) chip (3), wherein probes specific to a ClYVV isolate produced a positive reaction. All three samples tested were positive for ClYVV. To confirm this result, ClYVV-specific primers were designed using the sequences of four ClYVV isolates from NCBI (GenBank Accession Nos. AF185959, AF203536, DQ333346, and NC003536). Total RNA was extracted from symptomatic white clover samples using Easy-Spin Total RNA Extraction Kit (iNtRon, Daejeon, Korea) and used as template for RT-PCR. The positive control RNA was used from ClYVV GM isolate (KF975894) and negative control RNA used symptomless white clover plants. The ClYVV coat protein (CP) gene was amplified by RT-PCR using the specific primer pairs ClYVV-CP-F / ClYVV-CP-R (5'-CAAGAGCAGCACGATGAG-3' and 5'-CTCGCTCTATAAAGATCAGAT-3'). DNA fragments of the expected size (1,042 bp) were obtained from the white clover Korea isolate (AB930132), and the PCR product was cloned into a T&A cloning vector (RBC Bioscience, Taipei, Taiwan) and sequenced directly in both directions. BLAST analyses of the nucleotide sequence CP gene fragments revealed the highest identity with 98% with other ClYVV isolates (AF203536). To determine the experimental host range of the ClYVV Korea isolate, we inoculated five species (Chenopodium amaranticolor, C. quinoa, Nicotiana clevelandii, N. benthamiana, and Trifolium repens) in three families using this isolate. All test plants were mechanically inoculated with 0.1 M phosphate buffered saline (Takara, Tokyo, Japan). Each test plant was inoculated nine times and grown in a greenhouse maintained at 27 to 33°C. Necrotic local lesions were produced on inoculated leaves of C. amaranticolor, C. quinoa, and N. clevelandii 4 to 6 days post-inoculation. After 10 to 14 days, C. amaranticolor and C. quinoa showed systemic chlorotic spot symptoms, and N. clevelandii, N. benthamiana, and T. repens showed chlorotic spot, mild mosaic, and mosaic in the upper leaves, respectively. Up to now, in South Korea, ClYVV has been detected in gladiolus (Gladiolus gandavensis) (3) and soybean (Glycine max) (4). ClYVV can be easily transmitted by insect, aphid, or mechanical inoculation and has a host range including tobacco, soybean, etc. The presence of ClYVV could become an important threat to crop production in South Korea. To our knowledge, this is the first report of a ClYVV infection of the white clover plant in South Korea. References: (1) B. L. Denny and P. L. Guy. Australas. Plant Pathol. 38:270, 2009. (2) M. Nam et al. Plant Pathol. J. 30:51, 2014. (3) I. S. Park et al. Korean J. Plant Pathol. 14:74, 1998. (4) J. C. Shin et al. Plant Dis. 98:1283, 2014.

17.
Phys Rev Lett ; 111(9): 095002, 2013 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-24033042

RESUMEN

One of the important rotational resonances in nonaxisymmetric neoclassical transport has been experimentally validated in the KSTAR tokamak by applying highly nonresonant n=1 magnetic perturbations to rapidly rotating plasmas. These so-called bounce-harmonic resonances are expected to occur in the presence of magnetic braking perturbations when the toroidal rotation is fast enough to resonate with periodic parallel motions of trapped particles. The predicted and observed resonant peak along with the toroidal rotation implies that the toroidal rotation in tokamaks can be controlled naturally in favorable conditions to stability, using nonaxisymmetric magnetic perturbations.

18.
Phys Rev Lett ; 109(14): 145003, 2012 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-23083252

RESUMEN

Dual (or sometimes multiple) flux tubes (DFTs) have been observed in the core of sawtoothing KSTAR tokamak plasmas with electron cyclotron resonance heating. The time evolution of the flux tubes visualized by a 2D electron cyclotron emission imaging diagnostic typically consists of four distinctive phases: (1) growth of one flux tube out of multiple small flux tubes during the initial buildup period following a sawtooth crash, resulting in a single dominant flux tube along the m/n=1/1 helical magnetic field lines, (2) sudden rapid growth of another flux tube via a fast heat transfer from the first one, resulting in approximately identical DFTs, (3) coalescence of the two flux tubes into a single m/n=1/1 flux tube resembling the internal kink mode in the normal sawteeth, which is explained by a model of two current-carrying wires confined on a flux surface, and (4) fast localized crash of the merged flux tube similar to the standard sawtooth crash. The dynamics of the DFTs implies that the internal kink mode is not a unique prerequisite to the sawtooth crash, providing a new insight on the control of the sawtooth.

19.
Parasitology ; 139(10): 1361-74, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22657393

RESUMEN

Taenia solium, a causative agent of taeniasis and cysticercosis, has evolved a repertoire of lipid uptake mechanisms. Proteome analysis of T. solium excretory-secretory products (TsESP) identified 10 kDa proteins displaying significant sequence identity with cestode hydrophobic-ligand-binding-proteins (HLBPs). Two distinct 362- and 352-bp-long cDNAs encoding 264- and 258-bp-long open reading frames (87 and 85 amino acid polypeptides) were isolated by mining the T. solium expressed sequence tags and a cDNA library screening (TsHLBP1 and TsHLBP2; 94% sequence identity). They clustered into the same clade with those found in Moniezia expansa and Hymenolepis diminuta. Genomic structure analysis revealed that these genes might have originated from a common ancestor. Both the crude TsESP and bacterially expressed recombinant proteins exhibited binding activity toward 1-anilinonaphthalene-8-sulfonic acid (1,8-ANS), which was competitively inhibited by oleic acid. The proteins also bound to cis-parinaric acid (cPnA) and 16-(9-anthroyloxy) palmitic acid (16-AP), but showed no binding activity against 11-[(5-dimethylaminonaphthalene-1-sulfonyl) amino] undecanoic acid (DAUDA) and dansyl-DL-α-aminocaprylic acid (DACA). Unsaturated fatty acids (FAs) showed greater affinity than saturated FAs. The proteins were specifically expressed in adult worms throughout the strobila. The TsHLBPs might be involved in uptake and/or sequestration of hydrophobic molecules provided by their hosts, thus contributing to host-parasite interface interrelationships.


Asunto(s)
Regulación de la Expresión Génica , Proteínas del Helminto/genética , Proteínas del Helminto/metabolismo , Ligandos , Taenia solium/genética , Taenia solium/metabolismo , Secuencia de Aminoácidos , Animales , ADN Complementario/genética , Ácidos Grasos/metabolismo , Ácidos Grasos Insaturados/metabolismo , Perfilación de la Expresión Génica , Proteínas del Helminto/química , Interacciones Hidrofóbicas e Hidrofílicas , Datos de Secuencia Molecular , Filogenia , Unión Proteica , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Taenia solium/clasificación
20.
J Clin Pharm Ther ; 37(5): 614-6, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22642701

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: Proton pump inhibitors (PPIs), which are widely used for the treatment of peptic ulcers and gastroesophageal diseases, reduce both basal and stimulated gastric acid secretion by inhibiting the parietal cell enzyme H(+)-K(+)-adenosine triphosphatase. There have been several reports of hypersensitivity reactions to PPIs but anaphylaxis is very rare. We report on two cases of anaphylaxis to PPIs. CASE SUMMARY: Our two interesting and instructive cases of anaphylaxis to PPIs relate to the orally disintegrating form of lansoprazole and omeprazole. The first patient had taken esomeprazole 20 mg/day for 1 month without any side effects before experiencing anaphylaxis to lansoprazole. To our knowledge, this is the first report of anaphylaxis to the orally disintegrating form of lansoprazole. In the second case, the patient was misdiagnosed with penicillin allergy which she suffered from earlier. WHAT IS NEW AND CONCLUSION: Physicians need to be more aware of the possibility of hypersensitivity to PPIs.


Asunto(s)
Anafilaxia/inducido químicamente , Hipersensibilidad a las Drogas/etiología , Inhibidores de la Bomba de Protones/efectos adversos , Anciano , Femenino , Humanos , Persona de Mediana Edad , Inhibidores de la Bomba de Protones/uso terapéutico
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