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1.
Biomolecules & Therapeutics ; : 674-681, 2023.
Artículo en Inglés | WPRIM | ID: wpr-999689

RESUMEN

Bile pigment, bilirubin, and biliverdin concentrations may change as a results of biliary tract cancer (BTC) altering the mechanisms of radical oxidation and heme breakdown. We explored whether changes in bile pigment components could help distinguish BTC from benign biliary illness by evaluating alterations in patients with BTC. We collected bile fluid from 15 patients with a common bile duct stone (CBD group) and 63 individuals with BTC (BTC group). We examined the bile fluid’s bilirubin, biliverdin reductase (BVR), heme oxygenase (HO-1), and bacterial taxonomic abundance. Serum bilirubin levels had no impact on the amounts of bile HO-1, BVR, or bilirubin. In comparison to the control group, the BTC group had considerably higher amounts of HO-1, BVR, and bilirubin in the bile. The areas under the curve for the receiver operating characteristic curve analyses of the BVR and HO-1 were 0.832 (p<0.001) and 0.891 (p<0.001), respectively. Firmicutes was the most prevalent phylum in both CBD and BTC, according to a taxonomic abundance analysis, however the Firmicutes/Bacteroidetes ratio was substantially greater in the BTC group than in the CBD group. The findings of this study showed that, regardless of the existence of obstructive jaundice, biliary carcinogenesis impacts heme degradation and bile pigmentation, and that the bile pigment components HO-1, BVR, and bilirubin in bile fluid have a diagnostic significance in BTC. In tissue biopsies for the diagnosis of BTC, particularly for distinguishing BTC from benign biliary strictures, bile pigment components can be used as additional biomarkers.

2.
Annals of Surgical Treatment and Research ; : 140-150, 2021.
Artículo en Inglés | WPRIM | ID: wpr-889317

RESUMEN

Purpose@#In this pilot study, using next-generation sequencing and integrated messenger RNA (mRNA) sequencing, we investigated circulating microRNA (miRNA) expression profiling from bile-derived exosomes to identify dysregulated miRNA signatures and oncogenic pathways and determine their effects on targeted mRNAs in cholangiocarcinoma (CCA).Moreover, we explored the possibility that genetic analysis using bile-derived exosomes may replace gene analysis using tissue. @*Methods@#Bile was collected from a patient with perihilar CCA before curative resection. As a control, bile was collected from a patient with a common bile duct stone. Exosomes were isolated from the bile, and we performed next-generation miRNA sequencing using isolated exosomes. To evaluate miRNA-mRNA interactions, mRNA sequencing was performed using bile fluid in both patients. @*Results@#We identified 22 differentially expressed miRNAs. More than 65% of the predicted mRNA targets of those miRNAs were actually differentially expressed between control and CCA bile samples. In functional pathway analysis, targets of 22 miRNAs were primarily enriched in mitogen-activated protein kinase, platelet derived growth factor, vascular endothelial growth factor, epidermal growth factor receptor, and p53 signaling. In particular, in the functional assessment of miRNAmRNA interactions, RAS pathways, including downstream pathways (PI3K-AKT-mTOR and RAS-RAF-MEK-ERK), were determined to be enriched. @*Conclusion@#Circulating miRNAs in bile-derived exosomes provide new information for the development of miRNA analysis in CCA. These miRNAs may represent the oncogenic characteristics of CCA tissue, enabling them to be used instead of tissue samples for the diagnosis of CCA. Further research investigating circulating miRNAs in bile exosomes may lead to more rational, targeted approaches to treatment.

3.
Annals of Surgical Treatment and Research ; : 140-150, 2021.
Artículo en Inglés | WPRIM | ID: wpr-897021

RESUMEN

Purpose@#In this pilot study, using next-generation sequencing and integrated messenger RNA (mRNA) sequencing, we investigated circulating microRNA (miRNA) expression profiling from bile-derived exosomes to identify dysregulated miRNA signatures and oncogenic pathways and determine their effects on targeted mRNAs in cholangiocarcinoma (CCA).Moreover, we explored the possibility that genetic analysis using bile-derived exosomes may replace gene analysis using tissue. @*Methods@#Bile was collected from a patient with perihilar CCA before curative resection. As a control, bile was collected from a patient with a common bile duct stone. Exosomes were isolated from the bile, and we performed next-generation miRNA sequencing using isolated exosomes. To evaluate miRNA-mRNA interactions, mRNA sequencing was performed using bile fluid in both patients. @*Results@#We identified 22 differentially expressed miRNAs. More than 65% of the predicted mRNA targets of those miRNAs were actually differentially expressed between control and CCA bile samples. In functional pathway analysis, targets of 22 miRNAs were primarily enriched in mitogen-activated protein kinase, platelet derived growth factor, vascular endothelial growth factor, epidermal growth factor receptor, and p53 signaling. In particular, in the functional assessment of miRNAmRNA interactions, RAS pathways, including downstream pathways (PI3K-AKT-mTOR and RAS-RAF-MEK-ERK), were determined to be enriched. @*Conclusion@#Circulating miRNAs in bile-derived exosomes provide new information for the development of miRNA analysis in CCA. These miRNAs may represent the oncogenic characteristics of CCA tissue, enabling them to be used instead of tissue samples for the diagnosis of CCA. Further research investigating circulating miRNAs in bile exosomes may lead to more rational, targeted approaches to treatment.

4.
Keimyung Medical Journal ; : 77-97, 2021.
Artículo en Coreano | WPRIM | ID: wpr-917024

RESUMEN

This study was performed to select the proper assessing methods for learning outcomes in undergraduate education of medical humanities (MH), and to evaluate whether student assessments in MH curricula are related to the graduate outcomes (GO)and/or periodic phase outcomes (PO). We searched the reasonable assessing methods for GO and PO of MH curricula of Keimyung University School of Medicine (KUSM). The outcomes are composed of six competencies including patient care, communication, patient support, professionalism, problem solving and research, and self-development. Then, we analyzed whether student assessments carried out during formal MH curricula properly achieved their PO, furthermore their GO. Four competencies including communication, patient support, professionalism, self-development were lightened to be closely related to outcomes for MH. Only the component of problem solving was settled to be related to MH in the competency of problem solving and research. The competency of patient care was excluded from the relationship with MH. The assessing methods for the GO and three PO recommended from educational experts, and there were various available assessing methods based on medical situations and clinical contexts including direct observation of clinical skills, 360 degree feedback, peer review, self-assessment, project-based assessment, portfolio-based assessment, discussion & presentation-based assessment, log-based assessment. For the outcome-achieving from formal MH curricula, the MH programs of phase-1 (1st and 2nd grades) almost accomplished the PO of communication, patient supporting and professionalism, and considerably accomplished the PO of problem solving and self-development. The MH programs of phase-2 (3rd and 4th grades) accomplished considerably their PO as the competencies of professionalism and problem solving, and partially as communication, patient supporting and self-development. However, as only one program, public health law, was provided for MH program in phase-3 (5th and 6th grades), the extra methods to evaluate their MH outcomes are needed. Many assessing methods can be available for the most MH competencies consisting of the GO of KUSM, and the proper assessing methods for each MH competency should be selected based on programs and learning contexts in MH education. While formal MH curricula of the school variously accomplished the MH competencies of GO according to periodic phases of curricula, it is recommended to enhance the feasibility and effectiveness of evaluation for GO in MH curricula of the school.

5.
Korean Medical Education Review ; (3): 189-197, 2020.
Artículo | WPRIM | ID: wpr-836873

RESUMEN

The goal of this study is to present efficient measures to improve the quality of medical education through using a developed and applied continuous quality improvement (CQI) model suitable for medical education.To achieve this purpose, we developed a theoretical CQI model through a review of the literature according to the design-based research method. Through repetitive productive cyclical processes and professional reviews, we finally deduced an appropriate CQI model for medical education. The most important results of this study are as follows: First, the CQI model for medical education is defined as a quality management system with a cyclical course of planning, implementation, evaluation, and improvement of medical education.Second, the CQI model for medical education is composed of quality management activities of educational design, work, and evaluation. In addition, each activity has the implementation strategies of planning, doing, checking, and improving based on the PDCA model (Plan-Do-Check-Act model). Third, the CQI model for medical school education is composed of committees related to medical education doing improvement activities, as well as planning, implementing and evaluating it with CQI. As a result, we can improve teaching by using the CQI model for medical education. It is more meaningful because this gives us organized and practical measures of quality management and improvement in medical education as well as in the educational process.

6.
Keimyung Medical Journal ; : 11-16, 2019.
Artículo en Coreano | WPRIM | ID: wpr-786191

RESUMEN

The mission of an organization defines the fundamental reason for the organization's existence and serves as a compass that leads and guides the organization. This study aimed to develop a system regarding mission and vision in accordance with the value system of organizations. The Delphi questionnaires were formulated in such a way to reflect an open survey for the first survey and then a structured survey in the second survey. The validity of the Delphi survey results was analyzed using the content validity ratio (CVR).Missions include the reason for the existence of an organization and its management purpose. A vision is a blueprint that outlines the future roles and goals of an organization beyond its current position. Then, a strategy is seen as a method to achieve the mission and vision. Values are consistent principles and tenet. This study found through the web sites of all 40 medical schools that 9 schools (22.5%) had both missions and visions, 10 schools (25.0%) had only one of them, and 21 schools (52.5%) had none of them. this study recommends the inclusion of various stakeholder, the selection of a mission system, modification or improvements after re-analyzing the relationship, the use of the Delphi method, proofreading of the draft by Korean language experts, the suitability and notify about the mission development to medical school members.


Asunto(s)
Humanos , Métodos , Misiones Religiosas , Facultades de Medicina
7.
Keimyung Medical Journal ; : 11-16, 2019.
Artículo en Coreano | WPRIM | ID: wpr-917020

RESUMEN

The mission of an organization defines the fundamental reason for the organization's existence and serves as a compass that leads and guides the organization. This study aimed to develop a system regarding mission and vision in accordance with the value system of organizations. The Delphi questionnaires were formulated in such a way to reflect an open survey for the first survey and then a structured survey in the second survey. The validity of the Delphi survey results was analyzed using the content validity ratio (CVR).Missions include the reason for the existence of an organization and its management purpose. A vision is a blueprint that outlines the future roles and goals of an organization beyond its current position. Then, a strategy is seen as a method to achieve the mission and vision. Values are consistent principles and tenet. This study found through the web sites of all 40 medical schools that 9 schools (22.5%) had both missions and visions, 10 schools (25.0%) had only one of them, and 21 schools (52.5%) had none of them. this study recommends the inclusion of various stakeholder, the selection of a mission system, modification or improvements after re-analyzing the relationship, the use of the Delphi method, proofreading of the draft by Korean language experts, the suitability and notify about the mission development to medical school members.

8.
Keimyung Medical Journal ; : 11-16, 2019.
Artículo en Coreano | WPRIM | ID: wpr-917012

RESUMEN

The mission of an organization defines the fundamental reason for the organization's existence and serves as a compass that leads and guides the organization. This study aimed to develop a system regarding mission and vision in accordance with the value system of organizations. The Delphi questionnaires were formulated in such a way to reflect an open survey for the first survey and then a structured survey in the second survey. The validity of the Delphi survey results was analyzed using the content validity ratio (CVR).Missions include the reason for the existence of an organization and its management purpose. A vision is a blueprint that outlines the future roles and goals of an organization beyond its current position. Then, a strategy is seen as a method to achieve the mission and vision. Values are consistent principles and tenet. This study found through the web sites of all 40 medical schools that 9 schools (22.5%) had both missions and visions, 10 schools (25.0%) had only one of them, and 21 schools (52.5%) had none of them. this study recommends the inclusion of various stakeholder, the selection of a mission system, modification or improvements after re-analyzing the relationship, the use of the Delphi method, proofreading of the draft by Korean language experts, the suitability and notify about the mission development to medical school members.

9.
The Korean Journal of Internal Medicine ; : 612-621, 2018.
Artículo en Inglés | WPRIM | ID: wpr-714630

RESUMEN

BACKGROUND/AIMS: Grape seed proanthocyanidin extract (GSPE) has been reported to have a beneficial effect on regulating inf lammation. However, the anti-inflammatory mechanism of GSPE remains unclear. The aim of this study was to verify the influence of GSPE on the Toll-like receptor 4 (TLR4)-mediated signaling pathway in the regulation of murine autoimmune arthritis. METHODS: Collagen-induced arthritis (CIA) was induced in dilute brown non-agouti (DBA)/1J mice. The mice were treated with GSPE (0 or 100 mg/kg) intraperitoneally. The severity of arthritis was assessed clinically, biochemically, and histologically. Immunostaining for TLR4 was performed. The expressions of TLR4 and downstream signaling molecules were analyzed by Western blot. The effect of GSPE on lipopolysaccharide (LPS)-induced TLR4 activation was also evaluated using RAW264.7 cells and fibroblast-like synoviocytes (FLSs) from patients with rheumatoid arthritis and from those with osteoarthritis. RESULTS: GSPE attenuated the clinical severity of arthritis and decreased histological damage. GSPE treatment reduced the number of TLR4-stained cells in the synovium of mice with CIA. GSPE also downregulated the expression of TLR4, myeloid differentiation factor 88 (MyD88) and phosphorylated IκBα synovial protein in CIA mice. Concurrently, GSPE inhibited the nuclear translocation of nuclear factor-κB (NF-κB) subunits (p65 and p50). LPS-induced TLR4 activation was suppressed by GSPE in human FLS as well as in murine macrophages in vitro. CONCLUSIONS: Our results demonstrated that GSPE ameliorated CIA by regulating the TLR4-MyD88-NF-κB signaling pathway.


Asunto(s)
Animales , Humanos , Ratones , Artritis , Artritis Experimental , Artritis Reumatoide , Western Blotting , Técnicas In Vitro , Macrófagos , Factor 88 de Diferenciación Mieloide , Osteoartritis , Membrana Sinovial , Receptor Toll-Like 4 , Vitis
10.
Journal of Bacteriology and Virology ; : 179-188, 2017.
Artículo en Coreano | WPRIM | ID: wpr-194948

RESUMEN

Escherichia coli (E. coli) is a clinically important causative organism that can lead to urinary tract infections. Quinolone antibiotics are among the first-line treatments for urinary tract infections. However, the frequency of resistance to quinolone in E. coli has been increasing. Therefore, new antimicrobial agents that can be used for treatment in lieu of quinolone antibiotics are needed. In this study, thirty-six compounds with higher scores in a virtual screening based on the three-dimensional structure of E. coli DNA gyrase were selected for in vitro antimicrobial activity testing. An in vitro test confirmed the antimicrobial activity of 4-[(1-methyl-6-nitroquinolin-1-ium-4-yl)amino]-N-[4-[(1-methylpyridin-1-ium-4-yl)amino]phenyl]benzamide (ZINC18057104) against E. coli among the 36 compounds. The minimum inhibitory concentration (MIC) of ZINC18057104 against E. coli ATCC® 25922™ was 2 μg/ml, and the MIC₅₀ and MIC₉₀ for the 72 quinolone-resistant E. coli clinical isolates were 4 and 64 μg/ml, respectively. ZINC18057104, which has a quinoline structure which is similar to the quinolone antibiotics, is predicted to exhibit antimicrobial activity in quinolone-resistant E. coli because it has different molecular interactions with the DNA gyrase than that of existing quinolone antibiotics.


Asunto(s)
Antibacterianos , Antiinfecciosos , Girasa de ADN , ADN , Descubrimiento de Drogas , Escherichia coli , Técnicas In Vitro , Tamizaje Masivo , Pruebas de Sensibilidad Microbiana , Infecciones Urinarias
11.
The Korean Journal of Internal Medicine ; : 345-351, 2017.
Artículo en Inglés | WPRIM | ID: wpr-82837

RESUMEN

BACKGROUND/AIMS: The pathogen Acinetobacter baumannii is increasingly causing healthcare-associated infections worldwide, particularly in intensive care units. Biofilm formation, a factor contributing to the virulence of A. baumannii, is associated with long-term persistence in hospital environments. The present study investigates the clinical impact of biofilm production on colonization and acquisition after patient admission. METHODS: Forty-nine A. baumannii isolates were obtained between August and November 2013 from Keimyung University Dongsan Medical Center, Daegu, Korea. All isolates were obtained from sputum samples of new patients infected or colonized by A. baumannii. The microtiter plate assay was used to determine biofilm formation. RESULTS: Twenty-four A. baumannii isolates (48%) demonstrated enhanced biofilm formation capacity than that of the standard A. baumannii strain (ATCC 19606). All isolates were resistant to carbapenem, 38 isolates (77%) were collected from patients in an intensive care unit, and 47 isolates (95%) were from patients who had been exposed to antibiotics in the previous month. The median duration of colonization was longer for biofilm-producing isolates than that of the biofilm non-biofilm producing isolates (18 days vs. 12 days, p < 0.05). Simultaneous colonization with other bacteria was more common for biofilm-producing isolates than that for the non-biofilm producing isolates. The most prevalent co-colonizing bacteria was Staphylococcus aureus. CONCLUSIONS: Biofilm-producing isolates seem to colonize the respiratory tract for longer durations than the non-biofilm producing isolates. During colonization, biofilm producers promote co-colonization by other bacteria, particularly S. aureus. Additional research is required to determine possible links between biofilm formation and nosocomial infection.


Asunto(s)
Humanos , Acinetobacter baumannii , Acinetobacter , Antibacterianos , Bacterias , Biopelículas , Colon , Infección Hospitalaria , Unidades de Cuidados Intensivos , Corea (Geográfico) , Admisión del Paciente , Sistema Respiratorio , Esputo , Staphylococcus aureus , Virulencia
12.
Journal of Korean Medical Science ; : 552-558, 2015.
Artículo en Inglés | WPRIM | ID: wpr-99853

RESUMEN

Temporomandibular joint (TMJ) disorder is clinically important because of its prevalence, chronicity, and therapy-refractoriness of the pain. In this study, we investigated the effect of infliximab in a mouse model of TMJ pain using a specially-engineered transducer for evaluating the changes in bite force (BF). The mice were randomly divided into three groups (7 mice per group): the control group, the complete Freund's adjuvant (CFA) group, and the infliximab group. BF was measured at day 0 (baseline BF). After measuring the baseline BF, CFA or incomplete Freund's adjuvant was injected into both TMJs and then the changes in BF were measured at days 1, 3, 5, 7, 9, and 13 after the TMJ injection. For measuring the BF, we used a custom-built BF transducer. Control, CFA, and infliximab groups showed similar baseline BF at day 0. From day 1, a significant reduction in BF was observed in the CFA group, and this reduction in BF was statistically significant compared to that in the control group (P < 0.05). This reduction in BF was maintained until day 7, and BF started to recover gradually from day 9. In the infliximab group also, the reduction in BF was observed on day 1, and this reduction was maintained until day 7. However, the degree of reduction in BF was less remarkable compared to that in the CFA group. The reduction in BF caused by injection of CFA into the TMJ could be partially alleviated by the injection of anti-tumor necrosis factor alpha, infliximab.


Asunto(s)
Animales , Masculino , Ratones , Antirreumáticos/uso terapéutico , Fuerza de la Mordida , Modelos Animales de Enfermedad , Adyuvante de Freund/toxicidad , Infliximab/uso terapéutico , Ratones Endogámicos ICR , Articulación Temporomandibular/patología , Trastornos de la Articulación Temporomandibular/inducido químicamente , Factores de Tiempo
13.
Keimyung Medical Journal ; : 109-119, 2014.
Artículo en Coreano | WPRIM | ID: wpr-85996

RESUMEN

To investigate a specific mechanism of apoptosis induced by sonication, we applied 20 kHz ultrasound to leukemia cell line HL-60 with different intensities (0-60 W/cm2) and time durations (0-100 sec). In accordance with previous reports, ultrasound treatment in HL-60 cells induced immediate cell death and delayed cell death which are associated with cell lysis and apoptosis, respectively. Delayed cell death of HL-60 was also detected 5 hours after sonication in our experiment. Detection of caspase activation by Western blot and sub-G1 accumulation by flow cytometry confirmed that apoptosis plays a role in delayed cell death induced by sonication in HL-60 cells. In addition, we found that decrease in lysosomes of HL-60 cells after sonication suggesting lysosomal rupture is involved in the mechanism of cell death induced by sonication.


Asunto(s)
Humanos , Apoptosis , Western Blotting , Muerte Celular , Línea Celular , Citometría de Flujo , Células HL-60 , Leucemia , Lisosomas , Rotura , Sonicación , Terapia por Ultrasonido , Ultrasonografía
14.
Genomics & Informatics ; : 121-126, 2014.
Artículo en Inglés | WPRIM | ID: wpr-91761

RESUMEN

Medication adherence is generally defined as the extent of voluntary cooperation of a patient in taking medicine as prescribed. Adherence to long-term treatment with chronic disease is essential for reducing disease comorbidity and mortality. However, medication non-adherence in chronic disease averages 50%. This study was conducted a genome-wide association study to identify the genetic basis of medication adherence. A total of 235 medication non-adherents and 1,067 medication adherents with hypertension or diabetes were used from the Korean Association Resource project data according to the self-reported treatment status of each chronic disease, respectively. We identified four single nucleotide polymorphisms with suggestive genome-wide association. The most significant single nucleotide polymorphism was rs6978712 (chromosome 7, p = 4.87 x 10-7), which is located proximal to the GCC1 gene, which was previously implicated in decision-making capability in drug abusers. Two suggestive single nucleotide polymorphisms were in strong linkage disequilibrium (r2 > 0.8) with rs6978712. Thus, in the aspect of decision-making in adherence behavior, the association between medication adherence and three loci proximal to the GCC1 gene seems worthy of further research. However, to overcome a few limitations in this study, defining the standardized phenotype criteria for self-reported adherence should be performed before replicating association studies.


Asunto(s)
Humanos , Enfermedad Crónica , Comorbilidad , Consumidores de Drogas , Estudio de Asociación del Genoma Completo , Hipertensión , Desequilibrio de Ligamiento , Cumplimiento de la Medicación , Mortalidad , Fenotipo , Polimorfismo de Nucleótido Simple
15.
Journal of Bacteriology and Virology ; : 162-169, 2014.
Artículo en Inglés | WPRIM | ID: wpr-163001

RESUMEN

Gastric cancer is the third most common cancer and the third most frequent cause of cancer mortality in Asia. It is predicted that gastric cancer will remain an important cause of death at least during the next half century because of the increasing number of new cases in an aging population. However, little has been revealed about the role of gastric microbes and their reaction to gastric cancer. In this study, we identified differences in the microbial communities between gastric cancer and normal gastric mucosa by comparing the microbiomes of tissues from the same patients. The clustering analysis results showed different bacterial communities between normal gastric mucosa and gastric cancer. A comparison of bacterial communities at the species level revealed that Helicobacter pylori was significantly reduced in cancer tissue compared to that in normal gastric mucosa in the same patient. A comparison at the genus level showed that Propionibacterium spp., Staphylococcus spp., and Corynebacterium spp. had significantly reduced populations in cancer tissue, whereas Clostridium spp. and Prevotella spp. had significantly increased populations in cancer tissue.


Asunto(s)
Humanos , Envejecimiento , Asia , Causas de Muerte , Clostridium , Corynebacterium , Mucosa Gástrica , Helicobacter pylori , Microbiota , Mortalidad , Membrana Mucosa , Prevotella , Propionibacterium , Staphylococcus , Neoplasias Gástricas , Estómago
16.
Korean Journal of Dermatology ; : 600-607, 2013.
Artículo en Coreano | WPRIM | ID: wpr-117464

RESUMEN

BACKGROUND: UVB irradiation induces apoptosis or/and autophagy through several molecular pathways in keratinocytes. However, the precise molecular mechanism of UVB-induced autophagy is largely unknown in keratinocytes. OBJECTIVE: The purpose of this study was to investigate the molecular mechanisms of UVB-induced apoptosis and autophagy in HaCaT cell lines. METHODS: Cells were irradiated by UVB (Westinghouse FS-40 sunlamps) with various doses (0, 30, 60, 120, 240 mJ/cm2). The expression levels of caspase-3, Bax, Bcl2, Bcl-X(L) and LC3 were confirmed by Western blot analysis in UVB-irradiated HaCaT cell lines. Apoptotic cells were analyzed by PI staining, and autophagy cells were analyzed by immunofluorescent staining. RESULTS: The expression of Bcl-X(L) decreased from UVB 60 mJ/cm2 and Bcl2 decreased from UVB 240 mJ/cm2. The expression of caspase-3 was increased from UVB 120 mJ/cm2. These data showed that UVB-induced apoptosis is mediated by up-regulation of caspase-3 and down-regulation of Bcl2 and Bcl-X(L). Furthermore, the expression of LC3 increased from UVB 120 mJ/cm2. In addition, autophagy formation was observed in few fractions of apoptotic HaCaT cells in immunofluorescent staining; most apoptotic cells did not show autophagy formation. Moreover, autophagy formation inhibitor treatment induced a slight increment of apoptotic cell population under UVB irradiation. CONCLUSION: UVB irradiation induces not only apoptotic cell death but also autophagy formations; these events may create a defense mechanism for the prevention of apoptosis in UVB-treated HaCaT cells.


Asunto(s)
Apoptosis , Autofagia , Western Blotting , Caspasa 3 , Muerte Celular , Línea Celular , Regulación hacia Abajo , Queratinocitos , Regulación hacia Arriba
17.
Experimental & Molecular Medicine ; : 186-192, 2005.
Artículo en Inglés | WPRIM | ID: wpr-201944

RESUMEN

Ultraviolet B (UVB) irradiation of skin induces an acute inflammation. Cyclooxygenase-2 (COX-2) protein plays key roles in acute inflammation in UVB-irradiated keratinocyte cell line HaCaT. Recently, curcumin has been regarded as a promising anti-inflammatory agent due to its ability to inhibit COX-2 expression. However, it remains largely unknown whether curcumin inhibits the UVB-induced COX-2 expression in HaCaT cells. This study was undertaken to clarify the effect of curcumin on the expression of COX-2 in UVB- irradiated HaCaT cells and further determined the molecular mechanisms associated with this process. In this study, we have found that the expression of COX-2 mRNA and protein were up-regulated in UVB-irradiated HaCaT cells in a dose- and time-dependent manner. Interestingly, treatment with curcumin strongly inhibited COX-2 mRNA and protein expressions in UVB-irradiated HaCaT cells. Notably, there was effective inhibition by curcumin on UVB-induced activations of p38 MAPK and JNK in HaCaT cells. The DNA binding activity of AP-1 transcription factor was also markedly decreased with curcumin treatment in UVB-irradiated HaCaT cells. These results collectively suggest that curcumin may inhibit COX- 2 expression by suppressing p38 MAPK and JNK activities in UVB-irradiated HaCaT cells. We propose that curcumin may be applied as an effective and novel sunscreen drug for the protection of photoinflammation.


Asunto(s)
Humanos , Curcumina/farmacología , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Proteínas Quinasas JNK Activadas por Mitógenos/antagonistas & inhibidores , Queratinocitos/citología , Prostaglandina-Endoperóxido Sintasas/metabolismo , Factor de Transcripción AP-1/metabolismo , Rayos Ultravioleta , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores
18.
Journal of Bacteriology and Virology ; : 27-38, 2004.
Artículo en Inglés | WPRIM | ID: wpr-14991

RESUMEN

Recently the transcriptional up-regulation of human beta-defensin 2 (HBD-2) by lipopolysaccharide (LPS) was found to be associated with NF-kappaB binding site. Although the general mechanisms of NF-kappaB activation by LPS stimulation are well understood, less is known about the signal transduction pathway leading to LPS-induced NF-kappaB activation in human corneal epithelial (HCE) cells. The aim of this study was to investigate the intracellular signals involved in LPS-induced HBD-2 mRNA expression in HCE cells. Pretreatments of inhibitors for NF-kappaB, protein tyrosine kinase, p38 mitogen activated protein kinase (MAPK), and c-Jun N-terminal kinase (JNK) attenuated the LPS-induced NF-kappaB DNA binding activity and HBD-2 mRNA expression. Furthermore, pretreatments with inhibitors for protein kinase C (PKC), phosphatidylcholine-phospholipase C, phosphatidylinositol-phospholipase C, or phosphatidate phosphohydrolase prevented LPS-induced HBD-2 mRNA expression and HBD-2 prmoter-driven luciferase activity. However, the increased expression of HBD-2 mRNA and the increased DNA binding activity of NF-kappaB induced by LPS were not changed by the blockage of extracellular signal-regulated kinase (ERK) and of addition of antioxidants. Forskolin, a protein kinase A (PKA) agonist did not induce HBD-2 mRNA expression. These data demonstrate that LPS-induced HBD-2 mRNA expression via NF-kappaB is, at least in part, dependent on PKC, p38 MAPK, JNK, and protein tyrosine kinase status, but appears to be independent on PKA, ERK and ROS in HCE cells. Taken together, there may be more than one signaling pathways that lead to LPS-induced up-regulation of HBD-2 mRNA expression in HCE cells.


Asunto(s)
Humanos , Antioxidantes , Sitios de Unión , Colforsina , Proteínas Quinasas Dependientes de AMP Cíclico , ADN , Células Epiteliales , Proteínas Quinasas JNK Activadas por Mitógenos , Luciferasas , FN-kappa B , Proteínas Quinasas p38 Activadas por Mitógenos , Fosfatidato Fosfatasa , Fosfotransferasas , Proteína Quinasa C , Proteínas Quinasas , Proteínas Tirosina Quinasas , ARN Mensajero , Transducción de Señal , Regulación hacia Arriba
19.
Journal of Bacteriology and Virology ; : 235-243, 2003.
Artículo en Coreano | WPRIM | ID: wpr-39993

RESUMEN

Proteolytic degradation of the extracellular matrix and tumor metastasis correlate with the expression of endopeptidases known as matrix metalloproteinases (MMPs). Expression of MMPs is regulated by cytokines and signal transduction pathways including those activated by phorbol myristate acetate (PMA). We found that resveratrol, a phytoalexin present in grapes, significantly inhibits the PMA-induced increase of MMP-9 expression and activity. These effects of resveratrol were dose-dependent and correlated with the suppression of MMP-9 mRNA expression levels. PMA caused a 23-fold increase in MMP-9 promoter activity, which was suppressed by resveratrol. Transient transfection by MMP-9 constructs, in which specific transcriptional factors were mutagenized, indicated that the effects of PMA and resveratrol were mediated via AP1 and NFkB response elements. Resveratrol inhibited PMA-mediated activation of c-Jun Nterminal kinase (JNK) and protein kinase C (PKC)-delta activation. Therefore, we conclude that the inhibitory activities of resveratrol on MMP-9, JNK, and PKC-delta may have therapeutic potential for controlling growth and invasiveness of tumors.


Asunto(s)
Citocinas , Endopeptidasas , Matriz Extracelular , Metaloproteinasas de la Matriz , Metástasis de la Neoplasia , Fosfotransferasas , Proteína Quinasa C , Elementos de Respuesta , ARN Mensajero , Transducción de Señal , Acetato de Tetradecanoilforbol , Transfección , Vitis
20.
Journal of Bacteriology and Virology ; : 113-118, 2003.
Artículo en Coreano | WPRIM | ID: wpr-110749

RESUMEN

HL-60 cells (human promyelocytic leukemia cells) differentiate into the monocyte/macrophage like cells that die spontaneously by apoptosis when treated with 12-O-tetradecanoylphorbol-13-acetate (TPA). It is known that inhibitors of apoptosis proteins (IAP) bind to and inhibit caspase 3, 7, 9 activity and the induction of apoptosis. In this study, we examined the expression of IAP genes during TPA induced differentiation of HL-60 cells. During the differentiation, HIAP-1, HIAP-2, and XIAP expressions were decreased in protein levels. The pan-caspase inhibitor z-VAD-fmk blocked the decrease of HIAP-1 and HIAP-2, which indicates HIAP-1 and HIAP-2 could be caspase substrates. These findings suggest that the decrease of IAP proteins is related to the induction of apoptosis that is associated with TPA- induced HL-60 cell differentiation.


Asunto(s)
Humanos , Apoptosis , Caspasa 3 , Células HL-60 , Leucemia
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