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This study presents a mass-production process for conductive carbon membrane-type sponge electrodes derived from recyclable cellulose biowaste. It includes an all-in-one hydrogel fabrication process for mass production, which significantly shortens the complex and expensive process for the conventional process of catalytic electrodes based on conductive supporting substrates such as the gas diffusion layer (GDL). The presence of pre-adsorbed melamine powder in the all-in-one hydrogel induces internal diffusion of the gaseous reactant for the uniform growth of carbon nanotubes (CNTs) onto the sponge-like porous carbon aerogel with a relatively thick and tortuous pore structure, thereby providing the electrochemical properties and mechanical strength simultaneously required for the air electrodes of rechargeable and quasi solid-state zinc-air batteries.
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The aim of this study was to evaluate the antioxidant and antibacterial activity of Hovenia (Hovenia dulcis) monofloral honey produced in Korea. To produce Hovenia monofloral honey, Hovenia trees were surrounded by a net house, and honeybees were breed there over a 20-day period. Hovenia monofloral honey contained more than 95% of Hovenia pollen and showed physicochemical properties in agreement with the international honey standard (Codex). The total phenolic and flavonoid contents of Hovenia monofloral honey ranged from a 24.82-27.00 mg gallic acid equivalent/100 g honey and a 0.41-0.46 mg quercetin equivalent/100 g honey, respectively. In addition, to evaluate the functional properties of Hovenia monofloral honey, the antioxidant activity of Hovenia monofloral honey was estimated by using the 1,1-diphenyl-2-picrylhydrazyl radical and the 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging assay. Furthermore, Hovenia monofloral honey showed an antibacterial activity against foodborne gram positive (Listeria monocytogenes and Staphylococcus aureus) and gram negative bacteria (Salmonella Typhimurium and Escherichia coli O157:H7).
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PURPOSE: The diagnostic criteria of gastric intraepithelial neoplasia (IEN) are controversial across the world. We investigated how many discrepancies occur in the pathologic diagnosis of IEN and early gastric carcinoma in endoscopic submucosal dissection (ESD) specimens, and evaluated the reasons of the discordance. MATERIALS AND METHODS: We retrospectively reviewed 1,202 ESD specimens that were originally diagnosed as gastric IEN and early carcinoma at 12 institutions. RESULTS: The final consensus diagnosis of carcinoma were 756 cases, which were originally 692 carcinomas (91.5%), 43 high-grade dysplasias (5.7%), 20 low-grade dysplasias (2.6%), and 1 others (0.1%), respectively. High- and low-grade dysplasia were finally made in 63 and 342 cases, respectively. The diagnostic concordance with the consensus diagnosis was the highest for carcinoma (91.5%), followed by low-grade dysplasia (86.3%), others (63.4%) and high-grade dysplasia (50.8%). The general kappa value was 0.83, indicating excellent concordance. The kappa values of individual institutions ranged from 0.74 to 1 and correlated with the proportion of carcinoma cases. The cases revised to a final diagnosis of carcinoma exhibited both architectural abnormalities and cytologic atypia. The main differential points between low- and high-grade dysplasias were the glandular distribution and glandular shape. Additional features such as the glandular axis, surface maturation, nuclear stratification and nuclear polarity were also important. CONCLUSION: The overall concordance of the diagnosis of gastric IEN and early carcinoma in ESD specimens was excellent. It correlated with the proportion of carcinoma cases, demonstrating that the diagnostic criteria for carcinoma are more reproducible than those for dysplasia.
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Carcinoma in Situ/diagnóstico , Resección Endoscópica de la Mucosa/métodos , Neoplasias Gástricas/diagnóstico , Carcinoma in Situ/patología , Detección Precoz del Cáncer , Femenino , Humanos , Masculino , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Estudios Retrospectivos , Factores de Riesgo , Neoplasias Gástricas/patologíaRESUMEN
PURPOSE: Cefaclor, a second-generation oral cephalosporin, is known to cause IgE-mediated hypersensitivity. Assays of serum-specific IgE (sIgE) to cefaclor are commercially available via the ImmunoCAP system (Thermo Fisher Scientific). While serum levels of sIgE >0.35 kU/L are considered indicative of an allergy, some patients with cefaclor allergy show low serum IgE levels. This study aimed to evaluate the proper cut-off levels of sIgE in the diagnosis of immediate hypersensitivity to cefaclor. MATERIALS AND METHODS: A total of 269 patients with drug allergy history, who underwent assays of sIgE to cefaclor at Ajou University hospital and Dong-A University Hospital, were reviewed retrospectively. Among them, 193 patients exhibited cefaclor-induced immediate hypersensitivity with certain or probable causality of an adverse drug reaction according to the WHO-UMC (the World Health Organization-the Uppsala Monitoring Centre) algorithm, and 76 controls showed delayed hypersensitivity reactions to non-antibiotics. RESULTS: In total, 126 of the 193 patients (65.3%) experienced anaphylaxis; they had higher serum sIgE levels than patients with immediate hypersensitivity who did not experience anaphylaxis (6.36±12.39 kU/L vs. 4.28±13.61 kU/L, p<0.001). The best cut-off value for cefaclor-induced immediate hypersensitivity was 0.11 kU/L, with sensitivity of 80.2% and specificity of 81.6%. A cut-off value of 0.44 kU/L showed the best sensitivity (75.4%) and specificity (65.7%) for differentiating anaphylaxis from immediate hypersensitivity reactions. CONCLUSION: Patients with cefaclor anaphylaxis exhibit high serum IgE levels. A cut-off value of 0.11 kU/L of sIgE to cefaclor is proper for identifying patients with cefaclor allergy, and 0.44 kU/L may be useful to detect anaphylaxis.
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Anafilaxia/inducido químicamente , Antibacterianos/inmunología , Cefaclor/efectos adversos , Hipersensibilidad Inmediata/inmunología , Inmunoglobulina E/sangre , Adolescente , Adulto , Anciano , Anafilaxia/inmunología , Antibacterianos/efectos adversos , Estudios de Casos y Controles , Cefaclor/inmunología , Niño , Femenino , Humanos , Hipersensibilidad Inmediata/inducido químicamente , Hipersensibilidad Inmediata/diagnóstico , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Sensibilidad y Especificidad , Urticaria/inducido químicamente , Adulto JovenRESUMEN
Background/Aims: Endoscopic submucosal dissection (ESD) has been regarded as a curative treatment for early gastric cancer (EGC) in indicated cases. The aim of this study was to evaluate the nationwide long-term clinical outcomes of ESD for EGC in Korea. Methods: A prospective multicenter cohort study was performed to evaluate the long-term efficacy of ESD for EGC within pre-defined indications at 12 institutes in Korea. The cases that met the expanded criteria upon pathological review after ESD were followed for 5 years. The primary outcome was 5-year disease specific free survival. Results: Six hundred ninety-seven patients with 722 EGCs treated with ESD were prospectively enrolled and followed for 5 years. Complete resection was achieved in 81.3% of the cases, and curative resection was achieved in 86.1%. During the 5-year follow-up, the overall survival rate was 96.6%, and the disease specific free survival rate was 90.6%. Local recurrence developed in 0.9%, and metachronous tumor development occurred in 7.8%; both conditions were treated by endoscopic or surgical treatment. Distant metastasis developed in 0.5% during follow-up. Conclusions: ESD showed excellent long-term clinical outcomes and can be accepted as a curative treatment for patients with EGC who meet the expanded criteria in final pathology studies.
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Detección Precoz del Cáncer/mortalidad , Resección Endoscópica de la Mucosa/mortalidad , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/cirugía , Anciano , Supervivencia sin Enfermedad , Resección Endoscópica de la Mucosa/métodos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Estudios Prospectivos , República de Corea , Tasa de Supervivencia , Tiempo , Factores de Tiempo , Resultado del TratamientoRESUMEN
PURPOSE: To examine factors in the fear-avoidance model, such as pain, pain catastrophizing, fear-avoidance beliefs, physical disability, and depression and their relationships with physical and psychological quality of life in patients with rheumatic diseases. MATERIALS AND METHODS: The data were obtained from 360 patients with rheumatic diseases who completed self-report measures assessing study variables. Structural equation modeling was used to examine the hypothesized relationships among factors specified in the fear-avoidance model predicting physical and psychological quality of life. RESULTS: Final models fit the data well, explaining 96% and 82% of the variance in physical and psychological quality of life, respectively. Higher pain catastrophizing was related to stronger fear-avoidance beliefs that had a direct negative association with physical disability and depression, which, in turn, negatively affected physical quality of life. Pain severity was also directly related to physical disability. Physical disability also affected physical quality of life indirectly through depression. The hypothesized relationships specified in the model were also confirmed for psychological quality of life. However, physical disability had an indirect association with psychological quality of life via depression. CONCLUSION: The current results underscore the significant role of cognitive, affective, and behavioral factors in perceived physical disability and their mediated detrimental effect on physical and psychological quality of life in patients with rheumatic diseases. Implications for rehabilitation The fear-avoidance model is applicable to the prediction of quality of life in patients with rheumatic diseases. As pain-catastrophizing and fear-avoidance beliefs are important factors linked to physical disability and depression, intervening these cognitive factors is necessary to improve physical function and depression in patients with rheumatic diseases. Considering the strong association between depression and physical and psychological quality of life, the assessment and treatment of the former should be included in the rehabilitation of patients with rheumatic diseases. Interventions targeting physical function and depression are likely to be effective in terms of improving physical and psychological quality of life in patients with rheumatic diseases.
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Catastrofización , Depresión/psicología , Personas con Discapacidad/psicología , Miedo/psicología , Calidad de Vida , Enfermedades Reumáticas/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Negativismo , Trastornos FóbicosRESUMEN
PURPOSE: Little research has examined the role of pain catastrophizing (PC) in predicting suicide among patients with rheumatic disease or the mechanisms through which it works. This study examines whether depression, perceived social support (PSS), and perceived burdensomeness (PB) mediate the relationship between PC and suicide risk. It also examines the relative importance of sociodemographic, clinical, and psychological factors in predicting suicide risk. METHODS: Three hundred sixty patients from a rheumatology clinic in Korea completed measures of pain catastrophizing, social support, depression, and perceived burdensomeness. RESULTS: In hierarchical multiple regression analysis, the PC magnification, PB, physical disability, and PSS were significantly related to suicide risk. Results of the serial multiple mediation analysis indicated that the total indirect effect of PC magnification on suicide risk was significant while the direct effect was not. Four specific indirect effects of PC magnification were found to be statistically significant. First of all, PC magnification was associated with suicide risk through PB and through depression and PB. PC magnification was also associated with suicide risk through depression and PSS. Lastly, PC magnification was associated with suicide risk through depression, PSS, and PB. CONCLUSIONS: The identified pathways through which PC affects suicide risk suggest the importance of depression, PSS, and PB. Evaluation and intervention targeted at physical disability and the psychological factors of PC magnification, depression, PSS, and PB may be integrated into the management of suicide risk in patients with rheumatic disease.
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Catastrofización/psicología , Depresión/psicología , Enfermedades Reumáticas/psicología , Suicidio/psicología , Adulto , Anciano , Femenino , Humanos , Relaciones Interpersonales , Masculino , Persona de Mediana Edad , Percepción , República de Corea , Apoyo SocialRESUMEN
PURPOSE: Researchers recently suggested intravenous paracetamol as a potential cause of hypotension. We aimed to investigate risk factors of paracetamol- and propacetamol-associated adverse drug reactions (ADRs) in Korean individuals. METHODS: All adverse hypotension cases, regardless of suspected drug, and all ADRs associated with paracetamol and propacetamol use were collected from the Korea Adverse Event Reporting System database between 2011 and 2014. The seriousness, causality, and type of ADR were classified. RESULTS: Of 4,771 cases of adverse hypotension, 403 (8.4%) were reported to be related to propacetamol. This was comparable to the rate of hypotension associated with fentanyl (454, 9.5%), the major suspected drug of hypotension. Paracetamol-associated hypotension accounted for merely 1.2% (55 cases) of all hypotension cases. Among ADRs associated with propacetamol use, hypotension was the most common (37.1%), whereas cutaneous reactions were the primary paracetamol-associated ADR. Propacetamol/paracetamol-associated hypotension was frequently recorded in older patients (≥54 years) (53.9 ± 25.8 vs. 42.8 ± 21.7, P < 0.001) and taking more concomitant drugs (1.9 ± 5.0 vs. 1.1 ± 3.2, P < 0.001). Also, compared with other ADRs associated by propacetamol/paracetamol, hypotension was more commonly assessed as a serious outcome (27.3% vs. 11.4%, P < 0.001). Regarding concomitant medications, the risk for hypotension associated with propacetamol was significantly increased in patients simultaneously taking antibacterials (J01), cold preparations (R05), drugs for acid related disorders (A02), blood substitutes (B05), or antithrombotics (B01). CONCLUSIONS: Propacetamol was found to be a major suspected drug of pharmacologically associated hypotension in Korea. Older and male patients taking medications in combination with propacetamol/paracetamol should undergo monitoring of their blood pressure. Copyright © 2017 John Wiley & Sons, Ltd.
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Acetaminofén/análogos & derivados , Sistemas de Registro de Reacción Adversa a Medicamentos , Analgésicos/efectos adversos , Hipotensión/inducido químicamente , Acetaminofén/administración & dosificación , Acetaminofén/efectos adversos , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Analgésicos/administración & dosificación , Bases de Datos Factuales , Femenino , Humanos , Hipotensión/epidemiología , Masculino , Persona de Mediana Edad , República de Corea/epidemiología , Factores de Riesgo , Factores SexualesRESUMEN
BACKGROUND/AIMS: Endoscopic submucosal dissection (ESD) has been an established treatment for indicated early gastric cancer (EGC) without deterioration of quality of life (QOL) compared with surgical resection. The aim of this study was to evaluate long-term QOL in patients undergoing ESD for EGC. METHODS: Patients scheduled to undergo curative ESD for EGC were prospectively enrolled from 12 institutions between May 2010 and December 2011. Assessments of QOL with Korean versions of the European Organization for Research and Treatment of Cancer (EORTC) QOL questionnaire-core (QLQ-C30) and a gastric cancer-specific questionnaire (STO22) were performed at baseline and at 7 days, 3 months, and 6 months after ESD. RESULTS: A total of 666 subjects were assessed for QLQ-C30 and QLQ-STO22. The mean QLQ-C30 score was 69.5 at baseline, 68.8 at 7 days, 73.1 at 3 months, and 73.2 at 6 months. The global health status on the EORTC QLQ-C30 was significantly improved after 3 and 6 months (p=0.0003 and p<0.0001, respectively). The QLQ-C30 and STO22 scores were not significantly different, or they only slightly deteriorated between before and immediately after ESD, but they were significantly improved after 3 and 6 months (p<0.05). CONCLUSIONS: QOL did not deteriorate immediately after ESD, and it improved more significantly at up to 6 months in patients who underwent curative ESD for EGC without significant complications.
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Adenocarcinoma/cirugía , Resección Endoscópica de la Mucosa , Calidad de Vida , Neoplasias Gástricas/cirugía , Adenocarcinoma/patología , Anciano , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Prospectivos , Neoplasias Gástricas/patología , Encuestas y CuestionariosRESUMEN
BACKGROUND/AIMS: Endoscopic submucosal dissection (ESD) is an effective treatment for early gastric cancer (EGC) that has demonstrated a minimal risk of lymph node metastasis in retrospective studies. We sought to prospectively evaluate the short-term outcomes of ESD treatment in EGCs. METHODS: A prospective multicenter cohort study of neoplasms 3 cm or less in diameter at endoscopic size evaluation was performed in 12 Korean ESD study grouprelated university hospitals and the National Cancer Center. Resected specimens were evaluated by the central pathologic review board. RESULTS: A patient cohort (n=712) with a total of 737 EGCs was analyzed. The margin-free en bloc resection rate was 97.3%, and curative resection of 640 lesions (86.8%) was achieved. Lower curative resection rates were associated with lesions 2 to 3 cm in size prior to ESD compared with lesions 2 cm or less in size (78.6% vs 88.1%, respectively, p=0.009). Significant factors associated with noncurative resection were moderately or poorly differentiated histological type, posterior wall tumor location, tumor size larger than 3 cm, ulceration, and submucosal invasion. Delayed bleeding occurred in 49 patients (6.9%), and 12 patients (1.7%) exhibited perforations. CONCLUSIONS: ESD is an effective treatment with a high curative resection rate for EGCs that meets relatively conservative pre-ESD indications. Long-term survival outcomes should be evaluated in followup studies.
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Resección Endoscópica de la Mucosa/estadística & datos numéricos , Gastroscopía/estadística & datos numéricos , Neoplasias Gástricas/cirugía , Adulto , Anciano , Detección Precoz del Cáncer , Resección Endoscópica de la Mucosa/métodos , Femenino , Mucosa Gástrica/cirugía , Gastroscopía/métodos , Humanos , Masculino , Márgenes de Escisión , Persona de Mediana Edad , Estudios Prospectivos , Neoplasias Gástricas/patología , Resultado del Tratamiento , Carga TumoralRESUMEN
BACKGROUND: Discrepancies in the clinicopathologic parameters pre- and post-endoscopic submucosal dissection (ESD) sometimes necessitate additional surgical resection. The aim of this study was to assess such discrepancies in clinicopathologic parameters before and after ESD in the context of reducing the risk of failure of curative ESD. METHODS: Data on 712 early gastric cancer patients were prospectively collected from 12 university hospitals nationwide. The inclusion criteria were differentiated carcinoma <3 cm in size, no ulceration, submucosal invasion <500 µm, and no metastasis. Clinicopathologic factors were compared retrospectively. RESULTS: The discrepancy rate was 20.1 % (148/737) and the most common cause of discrepancy was tumor size (64 cases, 8.7 %). Ulceration, undifferentiated histology, and SM2 invasion were found in 34 (4.6 %), 18 (2.4 %), and 51 cases (6.9 %), respectively. Lymphovascular invasion (LVI) was observed in 34 cases (4.6 %). Cases with lesions exceeding 3 cm in size showed more frequent submucosal invasion, an elevated gross morphology, and upper and middle locations (p < 0.05). In the cases with ulceration, depth of invasion (DOI) was deeper than in the cases without ulceration (p = 0.005). Differentiation was correlated with DOI and LVI (p = 0.021 and 0.007). DOI was correlated with tumor size, ulceration, differentiation, LVI, gross type, and location. There were statistically significant differences between mucosal cancer cases and submucosal cancer cases in tumor size, differentiation, ulceration, LVI, and location. CONCLUSIONS: The overall discrepancy rate was 20.1 %. To reduce this rate, it is necessary to evaluate the DOI very cautiously, because it is correlated with other parameters. In particular, careful checking for SM-invasive cancer is required due to the high incidence of LVI irrespective of the depth of submucosal invasion.
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Adenocarcinoma/patología , Resección Endoscópica de la Mucosa , Gastrectomía , Mucosa Gástrica/patología , Neoplasias Gástricas/patología , Adenocarcinoma/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Detección Precoz del Cáncer , Femenino , Estudios de Seguimiento , Mucosa Gástrica/cirugía , Gastroscopía , Humanos , Escisión del Ganglio Linfático , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Estadificación de Neoplasias , Pronóstico , Estudios Prospectivos , República de Corea , Neoplasias Gástricas/cirugíaRESUMEN
The selective targeting of an integrin αvß3 receptor using radioligands may enable the assessment of angiogenesis and integrin αvß3 receptor status in tumors. The aim of this research was to label a peptidomimetic integrin αvß3 antagonist (PIA) with (99m)Tc(CO)3 and to test its receptor targeting properties in nude mice bearing receptor-positive tumors. PIA was reacted with tris-succinimidyl aminotriacetate (TSAT) (20 mM) as a PIA per TSAT. The product, PIA-aminodiacetic acid (ADA), was radiolabeled with [(99m)Tc(CO)3(H2O)3](+1), and purified sequentially on a Sep-Pak C-18 cartridge followed by a Sep-Pak QMA anion exchange cartridge. Using gradient C-18 reverse-phase HPLC, the radiochemical purity of (99m)Tc(CO)3-ADA-PIA (retention time, 10.5 min) was confirmed to be > 95%. Biodistribution analysis was performed in nude mice (n = 5 per time point) bearing receptor-positive M21 human melanoma xenografts. The mice were administered (99m)Tc(CO)3-ADA-PIA intravenously. The animals were euthanized at 0.33, 1, and 2 hr after injection for the biodistribution study. A separate group of mice were also co-injected with 200 µg of PIA and euthanized at 1 hr to quantify tumor uptake. (99m)Tc(CO)3-ADA-PIA was stable in phosphate buffer for 21 hr, but at 3 and 6 hr, 7.9 and 11.5% of the radioactivity was lost as histidine, respectively. In tumor bearing mice, (99m)Tc(CO)3-ADA-PIA accumulated rapidly in a receptor-positive tumor with a peak uptake at 20 min, and rapid clearance from blood occurring primarily through the hepatobiliary system. At 20 min, the tumor-toblood ratio was 1.8. At 1 hr, the tumor uptake was 0.47% injected dose (ID)/g, but decreased to 0.12% ID/g when co-injected with an excess amount of PIA, indicating that accumulation was receptor mediated. These results demonstrate successful (99m)Tc labeling of a peptidomimetic integrin antagonist that accumulated in a tumor via receptor-specific binding. However, tumor uptake was very low because of low blood concentrations that likely resulted from rapid uptake of the agent into the hepatobiliary system. This study suggests that for (99m)Tc(CO)3-ADA-PIA to be useful as a tumor detection agent, it will be necessary to improve receptor binding affinity and increase the hydrophilicity of the product to minimize rapid hepatobiliary uptake.
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Chloroquine (CQ) is used to treat malaria and a variety of inflammatory diseases including systemic lupus erythematosus and rheumatoid arthritis. However, CQ is known to cause cytotoxicity of which mechanism is still uncertain. This study investigated the molecular mechanism responsible for the cell death in CQ-treated A172 human glioblastoma cells. CQ-induced apoptotic cell death of the cells in a time- and concentration-dependent manner. CQ also increased the production of nitric oxide in the cells. However, the pretreatment with aminoguanidine (AG) and N-Omega-nitro-l-arginine methyl ester (NAME), nitric oxide synthase inhibitors, did not block the CQ-induced cell death. In contrast to NO level increase, the level of intracellular reactive oxygen species (ROS) and their extracellular release were transiently and mildly increased by CQ. In addition, CQ depleted cellular GSH content, which was accompanied with time-dependent increase in GSH peroxidase without any significant change in GSH reductase activity. Glutathione (GSH) S-transferase activity was only transiently increased at 15 min treatment with CQ. Furthermore, the CQ-induced cell death was significantly suppressed when intracellular GSH decrease was prevented by the pretreatment with N-acetylcysteine (NAC) or glutathione ethylester (GSH-EE). At the same time, the pretreatment of the cells with NAC and GSH-EE significantly blocked the CQ-induced NO increase, representing that CQ-induced NO increase was resulted from the depletion of GSH. CQ also induced time-dependent increase in Bax level and caspase-3 activity with no change in Bcl-2 level. Overall, these results suggest that CQ-induced NO increase and cell death are dependent on GSH depletion, the cellular redox changes.
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Antimaláricos/toxicidad , Antirreumáticos/toxicidad , Apoptosis , Cloroquina/toxicidad , Glutatión/metabolismo , Óxido Nítrico/metabolismo , Caspasa 3/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Glioblastoma , Glutatión Peroxidasa/metabolismo , Glutatión Reductasa/metabolismo , Glutatión Transferasa/metabolismo , Humanos , Nitritos/metabolismo , Oxidación-Reducción , Especies Reactivas de Oxígeno/metabolismo , Proteína X Asociada a bcl-2/metabolismoRESUMEN
There is an extremely high incidence of antimicrobial resistance of the clinical isolates of Staphylococcus aureus in Korea. This study carried out a molecular investigation to determine the prevalence of the community-associated antimicrobial-resistant S. aureus and methicillin-resistant S. aureus (MRSA). The percentage resistance from the nasal swabs of healthy volunteers in 2003 in Seoul is as follows: penicillin (91%), erythromycin (EM, 14%), gentamicin (GM, 9.3%), tetracycline (TE, 8.2%), cephalothin (4%), oxacillin (OX, MRSA; 3.8%), clindamycin (CC, 2.6%), ciprofloxacin (CIP, 0.8%), and sulfamethoxazole/trimethoprim (0.6%). The community-associated MRSA (C-MRSA) strains were examined by pulsed-field gel electrophoresis (PFGE) analysis of the SmaI macro-fragments, multilocus sequence typing (MLST), and staphylococcal cassette chromosome mec (SCCmec) typing using the PCR analysis. The Korean C-MRSA isolates were clustered into three distinct groups. One PFGE group containing the C-MRSA strains showed resistance to CC, EM, and GM, a high level (32-96 microg/ml) of resistance to methicillin, sequence type 5 (ST5), and SCCmec type II, which is the most common hospital associated-MRSA (H-MRSA) isolated in Korea. These results highlight the heterogeneous genetic background of the C-MRSA as well as the pervasiveness of the H-MRSA isolates in this community.
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Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus/efectos de los fármacos , Adolescente , Adulto , Antibacterianos/administración & dosificación , Proteínas Bacterianas/genética , Niño , Preescolar , Infecciones Comunitarias Adquiridas/epidemiología , Infecciones Comunitarias Adquiridas/microbiología , Electroforesis en Gel de Campo Pulsado , Humanos , Lactante , Recién Nacido , Corea (Geográfico)/epidemiología , Resistencia a la Meticilina , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Epidemiología Molecular , Proteínas de Unión a las Penicilinas , Reacción en Cadena de la Polimerasa , Prevalencia , Análisis de Secuencia de ADN , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/genética , Staphylococcus aureus/aislamiento & purificaciónRESUMEN
3-Monochloro-1,2-propanediol (MCPD) is a well-known by-product of acid-hydrolyzed soy sauce during its manufacturing process. To evaluate the immunotoxicity of MCPD, we investigated its effect on the thymic subset, delayed-type hypersensitivity, mixed-lymphocyte reaction and peritoneal macrophage activity. MCPD was administered by gavage for 14 days at 0, 25, 50, and 100 mg/kg/day to female Balb/c mice. The thymic subsets and annexin-V positive cells in thymic cells were quantified by flow cytometry. Mixed-lymphocyte reaction, delayed-type hypersensitivity and peritoneal macrophage activity were assessed. The mixed-lymphocyte reaction and delayed-type hypersensitivity were not significantly changed. However, there were significant increases in the apoptosis of mice treated with high dose of MCPD compared to the vehicle control. A significant decrease in the CD4+CD8+ thymic subset of mice treated with high dose of MCPD was observed. The activity of peritoneal macrophage was significantly reduced in high dose group. These results indicate that MCPD could modulate the immune function in Balb/c mice.
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Apoptosis/efectos de los fármacos , Esterilizantes Químicos/toxicidad , Hipersensibilidad Tardía/inmunología , Macrófagos Peritoneales/efectos de los fármacos , Subgrupos de Linfocitos T/efectos de los fármacos , Timo/efectos de los fármacos , alfa-Clorhidrina/toxicidad , Animales , Apoptosis/inmunología , Ciclo Celular/inmunología , Esterilizantes Químicos/inmunología , Femenino , Citometría de Flujo , Inmunohistoquímica , Inmunofenotipificación , Prueba de Cultivo Mixto de Linfocitos , Macrófagos Peritoneales/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Óxido Nítrico/inmunología , Organismos Libres de Patógenos Específicos , Subgrupos de Linfocitos T/inmunología , Timo/citología , Timo/inmunología , Factor de Necrosis Tumoral alfa/inmunología , alfa-Clorhidrina/inmunologíaRESUMEN
3-Monochloro-1,2-propanediol (MCPD) is a well-known by-product of acid-hydrolyzed soy sauce during its manufacturing process. MCPD has been reported genotoxic in vitro, and reproductive toxicity and carcinogenicity in rats. However, no previous studies have investigated MCPD-induced alterations in the immune system. In the present study, MCPD was administered by gavage for 14 days at 0, 25, 50, and 100 mg/kg per day to female Balb/c mice. The antibody-mediated immune response to sheep red blood cells (SRBC) was assessed using the antibody-forming cell (AFC) assay, and splenic cell phenotypes were quantified by flow cytometry. Hematological and histopathological changes were assessed. Mitogen-stimulated spleen lymphocyte proliferation and natural killer (NK) cell activity were evaluated. The T-lymphocyte blastogenesis by concanavalin A (Con A) or anti-CD3 and B-lymphocyte blastogenesis by lipopolysaccharide (LPS) were not significantly changed. There were no significant changes in the hematological and histopathological findings of MCPD-treated mice. However, the significant decrease in thymus weight was observed in 100 mg dose group, even though that did not change body weight gain. The cellularities of spleen and thymus were significantly reduced in high-dose group. Exposure to high dose of MCPD decreased the AFC response to SRBC in mice. There was a significant decrease in NK cell activity of mice treated with high dose of MCPD. These results indicate that MCPD could modulate the immune function in Balb/c mice.
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Contaminación de Alimentos , Glicerol/toxicidad , Sistema Inmunológico/efectos de los fármacos , Animales , Células Productoras de Anticuerpos/efectos de los fármacos , Peso Corporal/efectos de los fármacos , División Celular/efectos de los fármacos , Eritrocitos/inmunología , Femenino , Glicerol/análogos & derivados , Células Asesinas Naturales/efectos de los fármacos , Subgrupos Linfocitarios/efectos de los fármacos , Linfocitos/citología , Linfocitos/efectos de los fármacos , Ratones , Ratones Endogámicos BALB C , Mitógenos/farmacología , Tamaño de los Órganos/efectos de los fármacos , Ovinos , Bazo/citología , Bazo/efectos de los fármacos , alfa-ClorhidrinaRESUMEN
Asiatic acid (AA), a triterpene, decreased viability and induced apoptosis of HepG2 human hepatoma cells in a dose-dependent manner. AA also markedly increased intracellular Ca(2+) level, which was blocked by TMB-8 and dantrolene, intracellular Ca(2+) release blockers, but not by EGTA, an extracellular Ca(2+) chelator. Moreover, AA-induced apoptosis was significantly suppressed by treatment with TMB-8 and dantrolene, suggesting that intracellular Ca(2+) release may play an essential role in the AA-induced apoptosis. In addition, AA profoundly increased protein level of p53, which was also inhibited by BAPTA/AM, an intracellular Ca(2+) chelator, TMB-8 and dantrolene. Treatment with A23187, a Ca(2+) ionophore, or thapsigargin, a Ca(2+)-ATPase inhibitor, alone enhanced p53 nuclear accumulation, indicating that p53 accumulation is dependent on intracellular Ca(2+) increase. Furthermore, the viability of Hep3B, p53-null cells, was much higher than that of HepG2, p53-wild type cells, when treated with AA. Taken together, these results suggest that AA induced apoptosis through increased intracellular Ca(2+), which, in turn, enhanced p53 expression in HepG2 cells. These results further suggest that AA may be a valuable agent for the therapeutic intervention of human hepatomas.
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Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Calcio/metabolismo , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Triterpenos/farmacología , Proteína p53 Supresora de Tumor/biosíntesis , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Triterpenos Pentacíclicos , Células Tumorales CultivadasRESUMEN
Cyclooxygenases (COX) appear to be involved in the mechanism of apoptosis in various cancer cells. In this study we investigated the role of COX in the capsaicin (Cap)-induced apoptosis in SK-N-SH human neuroblastoma cells. Cap induced decreased cell viability and apoptosis in a dose-dependent manner. Cap also significantly reduced the basal generation of reactive oxygen species (ROS) and lipid peroxidation in a time-dependent fashion. Cap markedly suppressed the expression of COX-1 and COX-2. Pretreatment with NS-398, a selective COX-2 inhibitor, or indomethacin, a nonselective COX inhibitor, significantly enhanced the Cap-induced decreased cell viability and apoptosis. Exogenous application of an oxidant, H2O2, significantly prevented the Cap-induced apoptosis and suppressed the expression of COX isoforms. These results suggest that redox status-dependent regulation of COX expression may mediate apoptosis induced by Cap in human neuroblastoma cells.
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Apoptosis/fisiología , Capsaicina/farmacología , Isoenzimas/biosíntesis , Neuroblastoma/patología , Prostaglandina-Endoperóxido Sintasas/biosíntesis , Supervivencia Celular , Ciclooxigenasa 1 , Ciclooxigenasa 2 , Relación Dosis-Respuesta a Droga , Humanos , Isoenzimas/farmacología , Proteínas de la Membrana , Oxidantes , Oxidación-Reducción , Prostaglandina-Endoperóxido Sintasas/farmacología , Células Tumorales CultivadasRESUMEN
INTRODUCTION: The murine local lymph node assay (LLNA) was developed as an alternative to guinea pig models for the assessment of the xenobiotic contact sensitization potential. However, it would be advantageous to have an alternative endpoint to the usual radioisotopic-dependent measures. In the present study, we investigated the development of a nonradioisotopic endpoint for LLNA using immunohistochemistry. METHODS: Female Balb/c mice were treated by the topical application of strong sensitizers, 2,4-dinitrochlorobenzene (DNCB) and toluene diisocyanate (TDI), and a strong irritant, sodium lauryl sulfate (SLS), on the dorsum of both ears once daily for three consecutive days. The proliferation of cells in the auricular lymph node and ears was analyzed by means of the labeling index (LI) of bromodeoxyuridine (BrdU) incorporation into cells. RESULTS: Skin reactions, consisting of increased ear thickness and the presence of inflammatory cell infiltrates, were observed in mice treated with DNCB and TDI. The cell number and the weight of the lymph nodes in the mice treated with the allergens, DNCB and TDI, were increased compared to vehicle control. We observed an increase in the areas of the B220(+) cells in the lymph nodes of mice treated with allergens, as determined by immunohistochemistry. There was an increase in the percentage of B220(+) cells in mice treated with DNCB and TDI compared to the vehicle control, but not in those treated with SLS. Because we observed an increase in the percentage of B cells in the allergen-treated group, we measured the stimulation index (SI) in the cortex and medulla (C+M) of the lymph node. The SI values of the C+M in the lymph nodes of the mice treated with DNCB and TDI were increased more than threefold compared with that of the control. However, the SI of the C+M in the lymph nodes of the mice exposed to 25% SLS was not significantly increased compared to the vehicle control, although the lymph node weight of the SLS group was significantly increased. DISCUSSION: In Balb/c mice, BrdU immunohistochemistry showed its potential use for the identification and differentiation of chemicals with the capacity to induce irritation and sensitization. The results suggest that the measurement of the SI in the cortex and medulla of the lymph node using BrdU immunohistochemistry could provide a useful method to screen irritants and allergens.
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Alérgenos/toxicidad , Antimetabolitos , Bromodesoxiuridina , Dermatitis Alérgica por Contacto/patología , Irritantes/toxicidad , Ganglios Linfáticos/citología , Animales , Recuento de Células , División Celular/efectos de los fármacos , Separación Celular , ADN/biosíntesis , Determinación de Punto Final , Femenino , Citometría de Flujo , Inmunohistoquímica , Ganglios Linfáticos/efectos de los fármacos , Ratones , Ratones Endogámicos BALB CRESUMEN
Oxidative stress has been known to be involved in the mechanism of toxic effects of various agents on many cellular systems. In this study we investigated the role of reactive oxygen species (ROS) in 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced neuronal cell toxicity using SK-N-SH human neuroblastoma cells. TCDD inhibited proliferation of the cells in a dose-dependent manner, which was revealed by MTT staining, counting of cells stained with trypan blue and [3H]thymidine uptake assay. TCDD also suppressed the basal generation of ROS in a time- and concentration-dependent manner assessed by 2',7'-dichlorofluorescein fluorescence. In addition, TCDD induced a dose-dependent inhibition of lipid peroxidation, a biomarker of oxidative stress, whereas it significantly increased the level of glutathione (GSH), an intracellular free radical scavenger in the cells. Moreover, TCDD altered the activities of major antioxidant enzymes; increase in superoxide dismutase (SOD) and catalase, but decrease in glutathione peroxidase (GSH-Px) and glutathione reductase (GSH-Red). Pretreatment with L-buthionine-S,R-sulfoximine (BSO, 50 microM), an inhibitor of GSH synthesis, significantly prevented the TCDD-induced reduction in lipid peroxidation and cell proliferation. Interestingly, exogenous application of an oxidant, H2O2 (50 microM) markedly restored the inhibited cell proliferation induced by TCDD. Taken together, these results suggest that alteration of cellular redox balance may mediate the TCDD-induced inhibition of proliferation in human neuronal cells.