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1.
Plant Cell Environ ; 47(3): 976-991, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38164069

RESUMO

Mosses are vital components of ecosystems, exhibiting remarkable adaptability across diverse habitats from deserts to polar ice caps. Sanionia uncinata (Hedw.) Loeske, a dominant Antarctic moss survives extreme environmental condition through perennial lifecycles involving growth and dormancy alternation. This study explores genetic controls and molecular mechanisms enabling S. uncinata to cope with seasonality of the Antarctic environment. We analysed the seasonal transcriptome dynamics of S. uncinata collected monthly from February 2015 to January 2016 in King George Island, Antarctica. Findings indicate that genes involved in plant growth were predominantly upregulated in Antarctic summer, while those associated with protein synthesis and cell cycle showed marked expression during the winter-to-summer transition. Genes implicated in cellular stress and abscisic acid signalling were highly expressed in winter. Further, validation included a comparison of the Antarctic field transcriptome data with controlled environment simulation of Antarctic summer and winter temperatures, which revealed consistent gene expression patterns in both datasets. This proposes a seasonal gene regulatory model of S. uncinate to understand moss adaptation to extreme environments. Additionally, this data set is a valuable resource for predicting genetic responses to climatic fluctuations, enhancing our knowledge of Antarctic flora's resilience to global climate change.


Assuntos
Briófitas , Briófitas/genética , Ecossistema , Regiões Antárticas , Neve , Ambientes Extremos , Perfilação da Expressão Gênica
2.
Scand J Gastroenterol ; 59(1): 7-15, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37671790

RESUMO

BACKGROUND/AIMS: Acute peptic ulcer bleeding is the most common cause of non-variceal upper gastrointestinal bleeding (NVUGIB). Endoscopic hemostasis is the standard treatment. However, various conditions complicate endoscopic hemostasis. Transarterial visceral embolization (TAE) may be helpful as a rescue therapy. This study aimed to investigate the factors associated with rebleeding after TAE. METHODS: We retrospectively investigated the records of 156 patients treated with TAE between January 2007 and December 2021. Rebleeding was defined as the presence of melena, hematemesis, or hematochezia, with a fall (>2.0 g/dl) in hemoglobin level or shock after TAE. The primary outcomes were rebleeding rate and 30-day mortality. RESULTS: Seventy patients with peptic ulcer bleeding were selected, and rebleeding within a month after TAE occurred in 15 patients (21.4%). Among the patients included in rebleeding group, significant increases were observed in the prevalence of thrombocytopenia (73.3% vs. 16.4%, p<.001) and ulcers >1 cm (93.3% vs 54.5%, p = .014). The mean AIMS65 (albumin, international normalized ratio, mental status, systolic blood pressure, age >65 years) score (2.3 vs 1.4, p = .009) was significantly higher in the rebleeding group. Multivariate logistic analysis revealed that thrombocytopenia (odds ratio 31.92, 95% confidence interval 6.24-270.6, p<.001) and larger ulcer size (odds ratio 27.19, 95% confidence interval 3.27-677.7, p=.010) significantly increased the risk of rebleeding after TAE. CONCLUSION: TAE was effective in the treatment of patients with high-risk peptic ulcer bleeding. AIMS65 score was a significant predictor of rebleeding after TAE, and thrombocytopenia and larger ulcer size increased the risk of rebleeding after TAE.


Assuntos
Embolização Terapêutica , Hemostase Endoscópica , Úlcera Péptica , Trombocitopenia , Humanos , Idoso , Úlcera/terapia , Estudos Retrospectivos , Úlcera Péptica Hemorrágica/etiologia , Úlcera Péptica Hemorrágica/terapia , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia , Embolização Terapêutica/efeitos adversos , Trombocitopenia/terapia , Úlcera Péptica/complicações , Recidiva
3.
Environ Res ; 214(Pt 3): 113998, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35940229

RESUMO

We examined the seasonal cycle of radon concentration observed at King Sejong Station (KSG, 62°S), Antarctic Peninsula, during the period 2013-2016. The distribution of monthly radon concentration was found to be highly positively skewed from March through October (austral autumn to spring) due to large numbers of short-lived periods of high radon concentration. The global atmospheric chemistry model (CAM-Chem), which includes all global terrestrial sources of radon except for those in Antarctica, well reproduces the observed seasonal cycle of monthly-mean radon concentration at KSG. Further offline experiments suggest that uncertainties in radon emissions over South America and the Southern Ocean should be improved for the simulations of radon in Antarctica. The results demonstrate that seasonally varying transport of radon in the boundary layer from South America substantially affects the seasonality of monthly mean radon concentration at KSG. The composite analyses further reveal that high radon events at KSG are the result of a distinct east-west dipole-like structure associated with surface cyclonic circulation over the Bellingshausen Sea and anticyclonic circulation in the Weddell Sea. This atmospheric pattern provides favorable conditions for radon transport into KSG from the northwest. The relationship between radon concentration at KSG and climate variability is also discussed in this study.


Assuntos
Radônio , Regiões Antárticas , Clima , Estações do Ano
4.
Glob Chang Biol ; 27(17): 4040-4059, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33913236

RESUMO

The regional variability in tundra and boreal carbon dioxide (CO2 ) fluxes can be high, complicating efforts to quantify sink-source patterns across the entire region. Statistical models are increasingly used to predict (i.e., upscale) CO2 fluxes across large spatial domains, but the reliability of different modeling techniques, each with different specifications and assumptions, has not been assessed in detail. Here, we compile eddy covariance and chamber measurements of annual and growing season CO2 fluxes of gross primary productivity (GPP), ecosystem respiration (ER), and net ecosystem exchange (NEE) during 1990-2015 from 148 terrestrial high-latitude (i.e., tundra and boreal) sites to analyze the spatial patterns and drivers of CO2 fluxes and test the accuracy and uncertainty of different statistical models. CO2 fluxes were upscaled at relatively high spatial resolution (1 km2 ) across the high-latitude region using five commonly used statistical models and their ensemble, that is, the median of all five models, using climatic, vegetation, and soil predictors. We found the performance of machine learning and ensemble predictions to outperform traditional regression methods. We also found the predictive performance of NEE-focused models to be low, relative to models predicting GPP and ER. Our data compilation and ensemble predictions showed that CO2 sink strength was larger in the boreal biome (observed and predicted average annual NEE -46 and -29 g C m-2  yr-1 , respectively) compared to tundra (average annual NEE +10 and -2 g C m-2  yr-1 ). This pattern was associated with large spatial variability, reflecting local heterogeneity in soil organic carbon stocks, climate, and vegetation productivity. The terrestrial ecosystem CO2 budget, estimated using the annual NEE ensemble prediction, suggests the high-latitude region was on average an annual CO2 sink during 1990-2015, although uncertainty remains high.


Assuntos
Dióxido de Carbono , Ecossistema , Carbono , Dióxido de Carbono/análise , Reprodutibilidade dos Testes , Estações do Ano , Solo , Tundra , Incerteza
5.
J Med Virol ; 87(6): 993-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25712861

RESUMO

Acute hepatitis B, caused by hepatitis B virus (HBV) strains with drug resistant mutations or pre-core/basal core promoter (PC/BCP) mutations, is a public health concern, because this infection is often associated with poor disease outcome or difficulty in therapeutic choice. The HBV genotype, the prevalence of drug resistant mutations, and PC/BCP mutations in Korean patients with acute hepatitis B were studied. From 2006 to 2008, 36 patients with acute hepatitis B were enrolled prospectively in four general hospitals. Among them, 20 showed detectable HBV DNA (median value was 4.8 log copies/mL). HBV genotyping and analysis of HBV mutations that conferred resistance against lamivudine, adefovir, or entecavir and of PC/BCP mutations were performed using highly sensitive restriction fragment mass polymorphism (RFMP) analysis. All 20 patients were infected with HBV genotype C, which causes almost all cases of chronic hepatitis B in Korea. No patient showed mutations that conferred resistance against lamivudine (L180M, M204V/I), adefovir (A181T, N236S), or entecavir (I169M, A184T/V, S202I/G, M250V/I/L). However, four patients had BCP mutations, and two had PC mutations. Platelet counts were significantly lower in the four patients with PC/BCP mutations compared to those with wild type. In this study, all acute hepatitis B patients had genotype C HBV strains with no drug resistant mutations. However, 20% showed PC/BCP mutations. This highlights the need for further study on the significance of PC/BCP mutations.


Assuntos
Farmacorresistência Viral/genética , Antígenos do Núcleo do Vírus da Hepatite B/genética , Vírus da Hepatite B/genética , Hepatite B/virologia , Mutação , Regiões Promotoras Genéticas , Proteínas do Core Viral/genética , Adenina/análogos & derivados , Adenina/farmacologia , Adenina/uso terapêutico , Adulto , Idoso , Antivirais/farmacologia , Antivirais/uso terapêutico , DNA Viral/genética , DNA Viral/isolamento & purificação , Feminino , Genótipo , Guanina/análogos & derivados , Guanina/farmacologia , Guanina/uso terapêutico , Hepatite B/tratamento farmacológico , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/fisiologia , Humanos , Lamivudina/farmacologia , Lamivudina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Organofosfonatos/farmacologia , Organofosfonatos/uso terapêutico , Estudos Prospectivos , República da Coreia , Replicação Viral
6.
Scand J Gastroenterol ; 48(2): 196-204, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23194375

RESUMO

OBJECTIVES: To compare the efficacy of rescue therapies in lamivudine (LAM)-resistant chronic hepatitis B (CHB) infections including: (1) adefovir dipivoxil (ADV) monotherapy, (2) ADV plus LAM combination therapy and (3) entecavir (ETV) 1.0 mg monotherapy. MATERIALS AND METHODS: The authors designed a multicenter-retrospective study. Eight institutions participated in the study from Korea. RESULTS: A total of 343 LAM-resistant CHB patients were enrolled. The proportion of patients with undetectable serum hepatitis B virus (HBV) DNA levels at month 24 after the initiation of rescue therapy was higher in the ADV plus LAM combination therapy group (39/64, 60.9%) than in the ADV monotherapy (50/126, 39.7%) and ETV 1.0 mg monotherapy (19/48, 39.6%) groups (p = 0.014). Mean serum HBV DNA levels at 24 months were 2.07 ± 1.21 log(10) IU/ml in the ADV plus LAM combination therapy group, 2.74 ± 1.74 log(10) IU/ml in the ADV monotherapy group and 3.08 ± 1.97 log(10) IU/ml in the ETV 1.0 mg monotherapy group (p = 0.014). In multivariate analysis, a finding of undetectable serum HBV DNA level at 6 months and ADV plus LAM combination therapy (vs. ADV) was an independent factor for predicting undetectable serum HBV DNA at month 24 (odds ratio, 1.003; 95% confidence interval, 1.000-1.006; p = 0.026). CONCLUSIONS: ADV plus LAM combination therapy is more effective in reducing viral load than switching to ADV or ETV 1.0 mg in patients with LAM-resistant CHB.


Assuntos
Adenina/análogos & derivados , Antivirais/uso terapêutico , Farmacorresistência Viral , Guanina/análogos & derivados , Hepatite B Crônica/tratamento farmacológico , Lamivudina/uso terapêutico , Organofosfonatos/uso terapêutico , Adenina/uso terapêutico , Adulto , Esquema de Medicação , Quimioterapia Combinada , Feminino , Seguimentos , Guanina/uso terapêutico , Hepatite B Crônica/virologia , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Retrospectivos , Resultado do Tratamento , Carga Viral
7.
Korean J Gastroenterol ; 82(6): 304-309, 2023 12 25.
Artigo em Inglês | MEDLINE | ID: mdl-38130001

RESUMO

Small bowel variceal bleeding is a rare cause of gastrointestinal hemorrhage, with clinical manifestations ranging from asymptomatic incidental findings to life-threatening conditions. The diagnosis and management of small bowel bleeding are challenging because of the localization of the lesion and the difficulty of the procedure. Trans-arterial embolization (TAE) is a secure and straightforward method for treating ectopic varices. On the other hand, there have been limited local studies on the outcomes of TAE for patients with small bowel variceal hemorrhage. This paper reports patients diagnosed with small bowel variceal bleeding and treated with TAE.


Assuntos
Embolização Terapêutica , Varizes Esofágicas e Gástricas , Varizes , Humanos , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/terapia , Varizes Esofágicas e Gástricas/complicações , Varizes Esofágicas e Gástricas/diagnóstico , Varizes Esofágicas e Gástricas/terapia , Embolização Terapêutica/métodos , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico , Varizes/complicações , Resultado do Tratamento
8.
Sci Total Environ ; 803: 150002, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34482143

RESUMO

Dimethyl sulfide (DMS) produced by marine algae represents the largest natural emission of sulfur to the atmosphere. The oxidation of DMS is a key process affecting new particle formation that contributes to the radiative forcing of the Earth. In this study, atmospheric DMS and its major oxidation products (methanesulfonic acid, MSA; non-sea-salt sulfate, nss-SO42-) and particle size distributions were measured at King Sejong station located in the Antarctic Peninsula during the austral spring-summer period in 2018-2020. The observatory was surrounded by open ocean and first-year and multi-year sea ice. Importantly, oceanic emissions and atmospheric oxidation of DMS showed distinct differences depending on source regions. A high mixing ratio of atmospheric DMS was observed when air masses were influenced by the open ocean and first-year sea ice due to the abundance of DMS producers such as pelagic phaeocystis and ice algae. However, the concentrations of MSA and nss-SO42- were distinctively increased for air masses originating from first-year sea ice as compared to those originating from the open ocean and multi-year sea ice, suggesting additional influences from the source regions of atmospheric oxidants. Heterogeneous chemical processes that actively occur over first-year sea ice tend to accelerate the release of bromine monoxide (BrO), which is the most efficient DMS oxidant in Antarctica. Model-estimates for surface BrO confirmed that high BrO mixing ratios were closely associated with first-year sea ice, thus enhancing DMS oxidation. Consequently, the concentration of newly formed particles originated from first-year sea ice, which was a strong source area for both DMS and BrO was greater than from open ocean (high DMS but low BrO). These results indicate that first-year sea ice plays an important yet overlooked role in DMS-induced new particle formation in polar environments, where warming-induced sea ice changes are pronounced.


Assuntos
Camada de Gelo , Água do Mar , Regiões Antárticas , Sulfetos/análise
9.
J Med Virol ; 83(7): 1195-202, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21567423

RESUMO

The epidemiology and clinical outcomes of acute hepatitis C are different geographically. This study aimed to investigate the mode of infection, clinical characteristics, and outcomes of acute hepatitis C in Korea. Forty-seven patients with acute hepatitis C were enrolled consecutively in a study conducted in seven medical centers. The patients with the mean age of 45.8 years had mostly mild symptoms. A healthcare-related procedure was the most common exposure history (42.5%): acupuncture (17%), surgery (10.6%), needle-stick injury (8.5%), and other medical procedures (6.4%). There was no case of intravenous drug use. Twenty-one patients (44.7%) recovered spontaneously. Among the 16 patients who received antiviral therapy (34%), all of the 12 evaluable patients had a sustained virologic response, while 10 patients (21.3%) who did not receive antiviral therapy progressed to chronic infection. The overall seroconversion rate of anti-HCV antibody was 61.7%. The patients who recovered spontaneously had significantly lower rate of seroconversion compared with the patients who did not clear spontaneously the infection. In conclusion, acute hepatitis C in Korea was related to various healthcare procedures, including acupuncture, characterized by high rates of spontaneous recovery and low rates of seroconversion, which may be associated with different modes of infection and ethnic differences. The characteristics of acute hepatitis C in Asian countries warrants further study.


Assuntos
Hepatite C/transmissão , Acupuntura , Doença Aguda , Adulto , Idoso , Alanina Transaminase/análise , Antivirais/uso terapêutico , Feminino , Hepacivirus/fisiologia , Hepatite C/diagnóstico , Hepatite C/tratamento farmacológico , Hepatite C/epidemiologia , Anticorpos Anti-Hepatite C/análise , Anticorpos Anti-Hepatite C/biossíntese , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Ferimentos Penetrantes Produzidos por Agulha/sangue , RNA Viral/análise , Remissão Espontânea , República da Coreia , Fatores de Risco , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Resultado do Tratamento , Adulto Jovem
10.
J Med Virol ; 83(12): 2073-81, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22012713

RESUMO

Korea has recently experienced a nationwide outbreak of hepatitis A. This study aimed to investigate hepatitis A virus (HAV) genotypes and to compare clinical features between patients infected with HAV genotype IA and those with genotype IIIA. From September 2006 to August 2008, 595 patients with symptomatic hepatitis A were enrolled prospectively in four hospitals in Korea. Among them, 556 patients participated in this study by providing serum or stool samples for genotypic analysis. HAV RNA was detected in 499 patients (89.7%). Major genotypes included IA (n = 244, 48.9%) and IIIA (n = 244, 48.9%), and the remaining genotype was IB (n = 11, 2.2%). From September 2006 to August 2007, the distribution of genotypes IA and IIIA were 64.6% and 35.6%, respectively, which changed to 42.3% and 54.6%, respectively, from September 2007 to August 2008, indicating change of circulating HAV genotypes in the study period from IA to IIIA. Major patterns of amino acid substitution in the VP3/VP1 junction region were observed at position 512 (P → L) in genotype IA and at 520 (R → K) in genotype IIIA. Patients with genotype IIIA infection showed significantly higher aminotransferase levels, prothrombin time, and leukocyte count, with more severe symptoms than those with genotype IA at the time of admission. These results suggest the occurrence of a change of circulating HAV genotypes in recent community-wide outbreaks of hepatitis A in Korea, and genotype IIIA infection, compared with genotype IA infection, might show more severe clinical manifestations.


Assuntos
Vírus da Hepatite A Humana/classificação , Vírus da Hepatite A Humana/genética , Hepatite A/epidemiologia , Hepatite A/virologia , Adulto , Fezes/virologia , Feminino , Genótipo , Hepatite A/patologia , Vírus da Hepatite A Humana/isolamento & purificação , Humanos , Fígado/fisiopatologia , Testes de Função Hepática , Masculino , Mutação de Sentido Incorreto , Prevalência , Estudos Prospectivos , RNA Viral/genética , República da Coreia/epidemiologia , Soro/virologia , Resultado do Tratamento , Proteínas Virais/genética
11.
Korean J Hepatol ; 17(2): 120-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21757983

RESUMO

BACKGROUND/AIMS: Combination treatment consisting of hepatic arterial infusion chemotherapy with epirubicin and cisplatin (HAIC-EC) and systemic infusion of low-dose 5-fluorouracil (5-FU) are sometimes effective against advanced hepatocellular carcinoma (HCC). However, there is no effective treatment for advanced HCCs with arterioportal shunts (APS) or arteriovenous shunts (AVS). METHODS: We investigated a response and adverse events of a new combination protocol of repeated HAIC-EC and percutaneous intratumoral injection chemotherapy with a mixture of recombinant interferon-gamma (IFN-γ) and 5-FU (PIC-IF) in patients with far-advanced HCCs with large APSs or AVSs. RESULTS: There was a complete response (CR) for the large vascular shunts in all three patients and for all tumor burdens in two patients. Significant side effects were flu-like symptoms (grade 2) and bone marrow suppression (grade 2 or 3) after each cycle, but these were well-tolerated. CONCLUSIONS: These results suggest that the combination of HAIC-EC and PIC-IF is a new and promising approach for advanced HCC accompanied by a large APS or AVS.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Idoso , Angiografia , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Cisplatino/administração & dosagem , Epirubicina/administração & dosagem , Fluoruracila/administração & dosagem , Artéria Hepática , Humanos , Infusões Intra-Arteriais , Injeções Intramusculares , Interferon gama/administração & dosagem , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Masculino , Proteínas Recombinantes , Tomografia Computadorizada por Raios X , Carga Tumoral
12.
Nat Commun ; 12(1): 6879, 2021 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-34824215

RESUMO

The ongoing disproportionate increases in temperature and precipitation over the Arctic region may greatly alter the latitudinal gradients in greenup and snowmelt timings as well as associated carbon dynamics of tundra ecosystems. Here we use remotely-sensed and ground-based datasets and model results embedding snowmelt timing in phenology at seven tundra flux tower sites in Alaska during 2001-2018, showing that the carbon response to early greenup or delayed snowmelt varies greatly depending upon local climatic limits. Increases in net ecosystem productivity (NEP) due to early greenup were amplified at the higher latitudes where temperature and water strongly colimit vegetation growth, while NEP decreases due to delayed snowmelt were alleviated by a relief of water stress. Given the high likelihood of more frequent delayed snowmelt at higher latitudes, this study highlights the importance of understanding the role of snowmelt timing in vegetation growth and terrestrial carbon cycles across warming Arctic ecosystems.


Assuntos
Ciclo do Carbono , Desenvolvimento Vegetal , Neve , Tundra , Alaska , Mudança Climática , Ecossistema , Estações do Ano , Temperatura , Fatores de Tempo , Água
13.
J Med Virol ; 82(8): 1318-26, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20572083

RESUMO

The clinical outcome of symptomatic hepatitis A and the incidence and clinical characteristics of atypical presentation of hepatitis A were studied using prospective, multicenter design. The atypical presentation included delayed anti-hepatitis A virus (HAV) immunoglobulin M (IgM) seroconversion defined as positive anti-HAV IgM on the repeated test within 7 days of hospital admission after the initially negative result, prolonged cholestasis, and acute kidney injury (AKI). A total of 595 patients with symptomatic hepatitis A requiring hospital admission were enrolled prospectively from September 2006 to August 2008 in four major hospitals in a Korean city with a population of approximately 1 million. Clinical outcomes of symptomatic hepatitis A showed a case fatality rate of 0.2%, and fulminant hepatitis in 0.5%. Delayed anti-HAV IgM seroconversion was found in 6.4%, and was significantly associated with shorter intervals from symptom onset to hospital admission, higher body mass index, and lower alanine aminotransferase (ALT) level at admission. Prolonged cholestasis was found in 4.7% of patients, and could be predicted by preexisting chronic hepatitis B viral infection, prolonged prothrombin time, and higher total bilirubin level. AKI was complicated in 1.5%, which could be predicted by lower albumin level, higher ALT level, and higher white blood cell (WBC) count. More than half of the patients required hemodialysis. Substantial occurrence of delayed anti-HAV IgM seroconversion, prolonged cholestasis, and AKI was confirmed with various predictable factors, which could be helpful for accurate diagnosis and management of hepatitis A patients.


Assuntos
Anticorpos Anti-Hepatite A/sangue , Vírus da Hepatite A/imunologia , Hepatite A/epidemiologia , Hepatite A/patologia , Imunoglobulina M/sangue , Adulto , Colestase/virologia , Feminino , Hepatite A/complicações , Hepatite A/mortalidade , Hospitalização , Humanos , Incidência , Nefropatias/terapia , Nefropatias/virologia , Coreia (Geográfico)/epidemiologia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Mortalidade , Estudos Prospectivos , Diálise Renal , Fatores de Tempo
14.
Arch Virol ; 155(6): 1003-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20390311

RESUMO

Hepatitis E virus (HEV) was originally identified as the etiological agent of non-HAV enterically transmitted hepatitis. One HEV strain (FJ763142) was identified from an acute viral hepatitis E patient with IgM anti-HEV in Korea. The complete genome sequence consisted of 7,238 nucleotides (nt) plus a 22-nt poly(A) tail. The strain belongs to genotype IV, with 91% homology compared with AB197674, which was found in a Japanese patient who had traveled to China. This finding suggests that HEV genotype IV already circulates in Korea, and this HEV might be the first example of an indigenous strain.


Assuntos
Genoma Viral , Vírus da Hepatite E , Hepatite E/virologia , Análise de Sequência de DNA , Animais , Sequência de Bases , Feminino , Genótipo , Vírus da Hepatite E/classificação , Vírus da Hepatite E/genética , Vírus da Hepatite E/isolamento & purificação , Humanos , Coreia (Geográfico) , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia
15.
J Gastroenterol Hepatol ; 23 Suppl 2: S131-9, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19120886

RESUMO

BACKGROUND AND AIM: The gastroduodenal ulcer (GDU) mostly develops on the lesser curvature side of stomach and the anterior wall of duodenal bulb, irrespective of the etiologies including Helicobacter pylori infection, non-steroidal anti-inflammatory drugs, alcohol, etc. However, a clear explanation as to why ulcers are prevalent in these areas has still not been given. The current study was designed to evaluate whether the vascular endothelial growth factor (VEGF) polymorphism could predict susceptibility to GDU through deranged angiogenic activities. METHODS: A large scale case-control study based on known single nucleotide polymorphisms (SNP) of VEGF and another case control study based on the novel SNP of VEGF was performed through the SNP-IT assay using the SNP stream 25 k system. A site-directed mutagenesis and functional assay was executed to document the biological effect of a novel VEGF SNP on angiogenesis. RESULTS: Even though the case-control study between non-ulcer dyspepsia (NUD) and gastric ulcer (GU) patients was done in 10 SNP of the VEGF gene including -2488C/T, -634G/C, -7C/T, 3436G/C, 6112C/A, 6894C/T, 9374G/A, 9812C/T, 13128C/T, and 13553C/T, the analysis showed no statistically significant association between NUD and GU. Denaturing high-performance liquid chromatography analysis could identify two novel SNP of the VEGF gene, -1780T/C and IVS-99 G/C, among which -1780T/C showed a very strong association between NUD and GDU, presenting with OR=2.93 on codominant analysis (P<0.001), OR=8.62 on dominant analysis (P<0.001), and OR=3.21 on recessive analysis (P<0.001). The promoter assay using a site-directed mutagenesis and in vitro angiogenesis assay showed repressed transcription of the VEGF gene in gastric epithelial cells and defective tube formation in endothelial cells, both transfected with a plasmid containing -1780C/C mutant of VEGF gene. CONCLUSION: The novel VEGF polymorphism -1780T/C could significantly predict the predisposition to GDU after the exposure to etiologic risks, based on defective angiogenic activity.


Assuntos
Úlcera Duodenal/genética , Neovascularização Fisiológica/genética , Polimorfismo de Nucleotídeo Único , Úlcera Gástrica/genética , Fator A de Crescimento do Endotélio Vascular/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Células Cultivadas , Criança , Úlcera Duodenal/metabolismo , Úlcera Duodenal/fisiopatologia , Células Endoteliais/metabolismo , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Mutagênese Sítio-Dirigida , Razão de Chances , Regiões Promotoras Genéticas , Medição de Risco , Fatores de Risco , Úlcera Gástrica/metabolismo , Úlcera Gástrica/fisiopatologia , Transcrição Gênica , Transfecção , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto Jovem
16.
J Gastroenterol Hepatol ; 23(6): 976-84, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18444990

RESUMO

BACKGROUND AND AIM: Based on our previous studies that Artemisia asiatica extracts exert either antioxidative or cytoprotective actions against non-steroidal anti-inflammatory drugs or Helicobacter pylori-induced gastric mucosal injury, or imposes qualified ulcer healing in an acetic acid-induced gastric ulcer model, we investigated the protective effects of Artemisia asiatica extracts against ethanol-induced gastric mucosal injury. METHODS: Sprague-Dawley rats received 4 g/kg body weight (BW) of absolute ethanol intragastrically, which produced visible hemorrhagic gastric lesions 60 min later. RESULTS: In this animal setting, the pretreatment of Artemisia extracts (30 or 100 mg/kg BW), 1 h before ethanol administration, significantly attenuated the source of gastric injury, which was assessed with gross and microscopic analysis (P < 0.01). Protection from alcohol-induced damage with Artemisia pretreatment was associated with significantly decreased lipid peroxidation, protecting gastric mucosa from glutathione depletion, as well as the inhibition of the cytochrome 2E1 ethanol-metabolizing enzyme. It attenuated the expressions of ethanol-induced pro-inflammatory cytokines, including interleukin (IL)-1beta and interferon-gamma, a weak activation of IL-10, the inhibition of the alcohol-induced overexpression of intercellular adhesion molecule-1, and the considerable induction of heat shock protein-72 expression in gastric mucosal homogenates. CONCLUSION: The data suggest that the ethanol extracts of Artemisia asiatica exerted significant protection from alcohol-induced gastric mucosal injury through bio-regulation, which is essential for cytoprotection and anti-inflammation.


Assuntos
Antiulcerosos/uso terapêutico , Artemisia , Etanol/toxicidade , Mucosa Gástrica/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Úlcera Gástrica/tratamento farmacológico , Animais , Antiulcerosos/farmacologia , Modelos Animais de Doenças , Mucosa Gástrica/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/farmacologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/patologia , Resultado do Tratamento
17.
J Gastroenterol Hepatol ; 23 Suppl 2: S278-85, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19120912

RESUMO

BACKGROUND AND AIM: Helicobacter pylori (H. pylori) infection has been known to influence the gastric leptin and ghrelin secretion, for which the exact pathogenic role has not been documented yet. This study was designed to investigate the influence of H. pylori eradication on plasma or gastric levels of ghrelin, body mass index (BMI), and resultant levels of appetite in patients with peptic ulcer disease. METHODS: Twenty-two patients with H. pylori-associated active duodenal or gastric ulcer were treated with 7 weeks of antisecretory medication followed with 7 days of eradication regimen. The plasma and tissue ghrelin levels, tumor necrosis factor-alpha (TNF-alpha) mRNA, BMI, and appetite scale were checked before and after treatment. An additional endoscopic examination was conducted in 10 patients taking both ulcer treatment and H. pylori eradication. RESULTS: Gastric ghrelin mRNA expression was significantly increased after either ulcer healing or H. pylori eradication, whereas gastric TNF-alpha mRNA expression was decreased after ulcer treatment and H. pylori eradication. In parallel with these changes, the visual analog scales for hunger and prospective food consumption were significantly increased after ulcer healing and H. pylori eradication. An increase in BMI was not statistically related to ulcer healing and H. pylori eradication therapy. In the subgroup analysis of 10 patients performed with additional endoscopic examination, ulcer treatment was associated with increased plasma ghrelin level and tissue ghrelin expression irrelevant to H. pylori eradication. CONCLUSION: Restored tissue levels of ghrelin and improved status of appetite was achieved with gastric ulcer healing and H. pylori eradication.


Assuntos
Antibacterianos/uso terapêutico , Apetite/efeitos dos fármacos , Índice de Massa Corporal , Úlcera Duodenal/tratamento farmacológico , Grelina/metabolismo , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori , Inibidores da Bomba de Prótons/uso terapêutico , Úlcera Gástrica/tratamento farmacológico , Estômago/efeitos dos fármacos , Adulto , Idoso , Quimioterapia Combinada , Úlcera Duodenal/sangue , Úlcera Duodenal/microbiologia , Úlcera Duodenal/fisiopatologia , Ingestão de Alimentos/efeitos dos fármacos , Endoscopia Gastrointestinal , Feminino , Mucosa Gástrica/metabolismo , Grelina/sangue , Grelina/genética , Infecções por Helicobacter/sangue , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/metabolismo , Úlcera Gástrica/sangue , Úlcera Gástrica/microbiologia , Úlcera Gástrica/fisiopatologia , Resultado do Tratamento , Fator de Necrose Tumoral alfa/metabolismo , Cicatrização/efeitos dos fármacos
18.
Hepatogastroenterology ; 55(82-83): 578-81, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18613411

RESUMO

BACKGROUND/AIMS: Although the natural seroclearance rate of Hepatitis B surface antigen (HBsAg) is reported to be 0.4-2% in western countries, this is not well known in Korea. This study aimed to elucidate the rate of natural HbsAg seroclearance, factors associated with seroclearance and prognosis after seroclearance. METHODOLOGY: In 1999, 250 chronic HBsAg carriers without any history of antiviral treatment and without any evidence of liver cirrhosis or hepatocellular carcinoma were selected. Follow-up HBsAg/ anti-HBs tests were performed annually till 2004. During a mean follow-up period of 48 months, 24 patients were lost and 11 received antiviral treatment. Finally, 215 patients completed the study. RESULTS: HBsAg seroclearance was observed in 11 patients (6 males, 5 females). One-year seroclearance rate was 1.4%. All patients who achieved seroclearance were HBeAg (-)/HBV DNA (-) at the time of enrollment. Additionally, old age and normal serum alanine aminotransferase (ALT) level were the factors associated with seroclearance (p < 0.05, respectively). During the follow-up period, only mild transient elevations of ALT were observed in 4 patients and no serious complications were observed. CONCLUSIONS: Natural seroclearance occurred exclusively in patients who were HBeAg (-)/HBV-DNA (-), and annual rate of natural HBsAg seroclearance was 1.4%. No significant complications were observed after seroclearance.


Assuntos
Antígenos de Superfície da Hepatite B/sangue , Adulto , Idoso , Feminino , Seguimentos , Humanos , Coreia (Geográfico) , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Adulto Jovem
19.
Korean J Hepatol ; 14(1): 97-101, 2008 Mar.
Artigo em Coreano | MEDLINE | ID: mdl-18367862

RESUMO

Allopurinol-induced hypersensitivity syndrome is characterized by an idiosyncratic reaction involving multiple-organs, which usually begins 2 to 6 weeks after starting allopurinol. In rare cases, the adverse reactions to allopurinol are accompanied by a variety of liver injury, such as reactive hepatitis, granulomatous hepatitis, vanishing bile duct syndrome, or fulminant hepatic failure. Here we report a case with granulomatous hepatitis and ductopenia. A 69-year-old man with chronic renal failure, hyperuricemia, and previously normal liver function presented with jaundice, skin rash, and fever 2 weeks after taking allopurinol (200 mg/day). In histopathology, a liver biopsy specimen showed mild spotty necrosis of hepatocytes, marked cholestasis in parenchyma, and some granulomas in the portal area. There were vacuolar degeneration in the interlobular bile ducts and ductopenia in the portal tracts. Pathologic criteria strongly suggested the presence of allopurinol-induced granulomatous hepatitis with ductopenia and cholestasis. The patient fully recovered following the early administration of systemic corticosteroid therapy.


Assuntos
Alopurinol/efeitos adversos , Antimetabólitos/efeitos adversos , Doenças dos Ductos Biliares/induzido quimicamente , Ductos Biliares Intra-Hepáticos/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/patologia , Colestase/induzido quimicamente , Granuloma/induzido quimicamente , Idoso , Alopurinol/uso terapêutico , Antimetabólitos/uso terapêutico , Doenças dos Ductos Biliares/diagnóstico , Doenças dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia , Colestase/diagnóstico , Colestase/patologia , Toxidermias/patologia , Granuloma/patologia , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/tratamento farmacológico , Masculino
20.
Korean J Gastroenterol ; 50(3): 188-92, 2007 Sep.
Artigo em Coreano | MEDLINE | ID: mdl-17885285

RESUMO

Pneumatosis cystoides intestinalis is an uncommon condition of unknown etiology, characterized by the presence of multiple gas filled cysts in the gastrointestinal tract. Many different causes of pneumatosis cystoides intestinalis have been proposed, including mechanical, pulmonary, and bacterial causes. Approximately 85% of cases are thought to be secondary to coexisting disorders of the gastrointestinal tract or the respiratory system. The condition has been associated with the therapeutic uses of lactulose, steroids, and various cancer chemotherapeutic regimens. Lactitol is a disaccharide analogue of lactulose which is available as a pure crystalline powder. There are three previous case reports suggestive of lactulose causing pneumatosis intestinalis. We report a case of recurrent pneumatosis cystoides intestinalis associated with benign recurrent pneumoperitoneum developed probably secondary to lactitol therapy.


Assuntos
Pneumatose Cistoide Intestinal/diagnóstico , Pneumoperitônio/diagnóstico , Adulto , Catárticos/efeitos adversos , Catárticos/uso terapêutico , Feminino , Humanos , Pneumatose Cistoide Intestinal/diagnóstico por imagem , Pneumatose Cistoide Intestinal/etiologia , Pneumoperitônio/complicações , Recidiva , Álcoois Açúcares/efeitos adversos , Álcoois Açúcares/uso terapêutico , Tomografia Computadorizada por Raios X
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