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1.
Blood Purif ; 53(3): 200-209, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37989110

RESUMO

INTRODUCTION: Left ventricular diastolic dysfunction (LVDD) frequently occurs in haemodialysis patients and is associated with adverse outcomes. Lung ultrasound (LUS) has been recently proposed for the quantification of extravascular lung water through assessment of B-lines. LUS findings and their relationship with LVDD in clinically euvolemic haemodialysis patients were investigated in this study. METHODS: Echocardiography and LUS examinations were performed on each patient. Multivariate linear regression and forward stepwise logistic regression were performed to determine the relationship between B-lines and LVDD. A receiver operating characteristic (ROC) curve with area under the curve (AUC) was calculated to determine the accuracy of B-lines for evaluating LVDD. RESULTS: A total of 119 patients were enrolled. The number of B-lines was statistically related to echocardiographic parameters (LAVI, LVEDVI, E/A, and E/e') of diastolic function, while the relationship between B-lines and LVEF disappeared after adjusting for potential confounding factors. Additionally, compared with the mild B-line group (B-lines: <14), the moderate (B-lines: 14-30) and severe B-line groups (B-lines: >30) were associated with an increased risk of LVDD (OR 24.344, 95% CI 4.854-122.084, p < 0.001, and OR 94.552, 95% CI 9.617-929.022, p < 0.001, respectively). Furthermore, the AUC of the ROC curve for B-lines predicting LVDD was 0.845, and the cut-off of B-lines was 14.5 (sensitivity 64.91%, specificity 93.55%). CONCLUSION: LUS B-lines were closely associated with left ventricular diastolic function in clinically euvolemic haemodialysis patients. Moreover, our findings suggested a B-line ≥14.5 as a reliable cut-off value for identifying patients with LVDD. LUS B-lines may be used as a novel indicator for evaluating LVDD.


Assuntos
Diálise Renal , Disfunção Ventricular Esquerda , Humanos , Diálise Renal/efeitos adversos , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/etiologia , Ecocardiografia/efeitos adversos , Curva ROC , Pulmão , Função Ventricular Esquerda
2.
Bioinformatics ; 39(9)2023 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-37682111

RESUMO

MOTIVATION: In recent years, the development of natural language process (NLP) technologies and deep learning hardware has led to significant improvement in large language models (LLMs). The ChatGPT, the state-of-the-art LLM built on GPT-3.5 and GPT-4, shows excellent capabilities in general language understanding and reasoning. Researchers also tested the GPTs on a variety of NLP-related tasks and benchmarks and got excellent results. With exciting performance on daily chat, researchers began to explore the capacity of ChatGPT on expertise that requires professional education for human and we are interested in the biomedical domain. RESULTS: To evaluate the performance of ChatGPT on biomedical-related tasks, this article presents a comprehensive benchmark study on the use of ChatGPT for biomedical corpus, including article abstracts, clinical trials description, biomedical questions, and so on. Typical NLP tasks like named entity recognization, relation extraction, sentence similarity, question and answering, and document classification are included. Overall, ChatGPT got a BLURB score of 58.50 while the state-of-the-art model had a score of 84.30. Through a series of experiments, we demonstrated the effectiveness and versatility of ChatGPT in biomedical text understanding, reasoning and generation, and the limitation of ChatGPT build on GPT-3.5. AVAILABILITY AND IMPLEMENTATION: All the datasets are available from BLURB benchmark https://microsoft.github.io/BLURB/index.html. The prompts are described in the article.

3.
Int J Biol Macromol ; 251: 126320, 2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37579905

RESUMO

A novel antibacterial indicator film was prepared by mixing corn starch with tangerine peel essential oil (TEO) Pickering emulsion emulsified by ultrasonic and esterified modified starch (UDSt), and then incorporated with purple corncob anthocyanin (PCA), which was used to monitor the freshness of pork. The results showed that the UDSt can effectively stabilize the TEO emulsion. PCA showed obvious color changes at different pH. With the increase of pH, the color of film changed from red to yellow, and its response to volatile ammonia changed from pink to cyan, showing better response ability. The loading of TEO conferred the film excellent bacteriostatic ability against E. coli and S. aureus. The film also had good ability of light blocking and free radical scavenging. In the process of pork deterioration, the antibacterial indicator film changed from pink to yellow, which was closely related to pork quality and had a good linear indicator correlation. The addition of TEO reduced the release of PCA in the antibacterial indicator film and helped to maintain the functional properties of the film. This type of antibacterial indicator film had considerable application potential in indicating food freshness.

4.
Carbohydr Polym ; 273: 118579, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34560983

RESUMO

In this paper, a novel biosorbent of SNCs-PEI was successfully prepared by grafting polyethylenimine (PEI) onto the starch nanocrystals (SNCs) using glutaraldehyde as a crosslinking agent. The optimal preparation conditions of SNCs-PEI were determined by the orthogonal experiments of the three-factor and three-level, and the SNCs-PEI was characterized by Fourier transform infrared spectroscopy (FT-IR), energy-dispersive X-ray spectroscopy (EDAX), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The zeta potential of SNCs-PEI was +26.3 mV (pH 7), which had a good adsorption performance for the anionic dye methyl blue (MB). The adsorption kinetics and isotherm of MB by SNCs-PEI were studied. At the temperature of 25, 30 and 35 °C, its maximum adsorption capacity was 337.84, 377.36 and 383.14 mg g-1, respectively. The adsorption of MB by the SNCs-PEI was a spontaneous and endothermic process according to the thermodynamic analysis.

5.
Int J Biol Macromol ; 167: 1241-1247, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33189752

RESUMO

The green hard capsules were prepared with corn nano-starch (CNS) and cellulose nanocrystal (CNC) in this study, the glycerol and carrageenan were used as plasticizer and gelling agent in the CNS/CNC gel solution, respectively. The capsule-films with different CNC content were prepared by casting method, and the dipping method was used in preparation of the corresponding capsules. The compatibility of CNS/CNC capsules was analyzed by Fourier Transform Infrared spectroscopy (FTIR) and X-Ray Diffraction (XRD), and the morphology of the capsules was analyzed by Scanning Electron Microscopy (SEM). The results showed that the tensile strength of the CNS based capsule-film was significantly improved with the addition of CNC. When the content of CNC was 6.0%, the tensile strength increased by 238.10%. The transparency of the capsule with different CNC contents was slightly reduced, but was greater than 87.0%. The loss on drying of CNS/CNC capsule was between 12.87% and 15.03%, and it could be completely dissolved in the artificial gastric juice within 6.0 min, which was in accordance with the provisions of Chinese Pharmacopoeia (2015).


Assuntos
Celulose/química , Nanocompostos/química , Nanopartículas/química , Amido/química , Cápsulas , Carragenina/química , Glicerol/química , Microscopia Eletrônica de Varredura , Nanocompostos/ultraestrutura , Nanopartículas/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/isolamento & purificação , Temperatura , Resistência à Tração , Viscosidade , Difração de Raios X , Zea mays/química
6.
Int J Biol Macromol ; 132: 1155-1162, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30981769

RESUMO

In the present study, in order to improve the properties of nanostarch-based nanocomposite film for food packaging, a type of nanocomposite film based on corn nanostarch (CNS) as the matrix and modified cellulose nanocrystals (modified-CNCs) as the reinforcement was prepared using a solution casting method. The cellulose nanocrystals (CNCs) were modified by a two-step method in which they were initially crosslinked with citric acid, and subsequently amidated with chitosan. Then, a type of CNS/modified-CNCs nanocomposite film with different content levels of modified-CNC were prepared and characterized using Fourier Transform Infrared spectroscopy (FTIR); X-ray Photoelectron Spectroscopy (XPS); X-Ray Diffraction (XRD); Differential Scanning Calorimetry (DSC); and Scanning Electron Microscopy (SEM). It was observed that when compared with the pure CNS film, the 8.0 wt% modified-CNCs loaded nanostarch-based nanocomposite film had displayed a 230.0% increase in tensile strength. And the moisture absorption ability had decreased by 25.6%; water vapor permeability had decreased by 87.4%; and the water contact angle value had increased by 18.1%. Also the results of this experimental study had revealed that the CNS/modified-CNCs nanocomposite film had displayed better antimicrobial activities against E. coli and S. aureus bacteria when compared with the pure CNS film.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Celulose/química , Nanocompostos/química , Nanopartículas/química , Escherichia coli/efeitos dos fármacos , Embalagem de Alimentos , Permeabilidade , Staphylococcus aureus/efeitos dos fármacos , Vapor , Resistência à Tração
7.
Cardiorenal Med ; 4(1): 53-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24847334

RESUMO

BACKGROUND: The therapeutic role of L-carnitine (LC) on the anemia of chronic hemodialized patients is still controversial. In order to clarify the long-term effects of LC administration on renal anemia, an open, observational 12-month study was performed. METHODS: Twenty stable outpatients undergoing hemodialysis were administered LC 900 mg p.o. daily for 12 months. The recombinant human erythropoietin (rHuEPO) dose was adjusted monthly when necessary to maintain the target hemoglobin (Hb) levels. RESULTS: The free LC level increased, while the acyl/free LC ratio decreased significantly 3 months after administration and was then maintained until the end of the study. There was no difference in Hb levels and the erythropoietin resistance index (ERI) during the study period. However, it was observed that ERI decreased significantly in 7 out of 18 patients (responders) 5 months after LC administration and was maintained thereafter (almost 40% reduction of the rHuEPO dose). The acyl/free carnitine ratio at baseline was the most contributing factor distinguishing responders from nonresponders. CONCLUSION: Although the beneficial effect of LC supplementation on renal anemia was not observed in all patients, at least 40% of the patients (responders) showed a significant improvement in ERI after long-term LC administration.

8.
Nephron Extra ; 4(1): 33-41, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24803919

RESUMO

BACKGROUND: It is well known that the physical activity in chronic hemodialysis patients decreases compared to that in normal subjects. In order to investigate the effects of L-carnitine on physical capacity and lipid metabolism, a cardiopulmonary exercise test using a bicycle ergometer was performed before and after 3 months of oral L-carnitine supplementation under double-blind conditions. METHODS AND RESULTS: A total of 20 stable outpatients undergoing hemodialysis treatment were randomly divided into 2 groups: controls receiving placebo and patients receiving 900 mg L-carnitine p.o. daily. The levels of free and acyl carnitine increased significantly from 22.9 ± 7.3 to 149.9 ± 51.8 µmol/l and from 16.0 ± 2.8 to 100.3 ± 50.2 µmol/l, respectively, in the L-carnitine group; however, there was no significant change in other plasma lipid profiles. The exercise time was decreased and the heart rate at the anaerobic threshold was increased in the control group 3 months after the study period, but there were no such changes observed in the L-carnitine group. The minute ventilation/CO2 output slope increased significantly from 38.9 ± 7.8 to 43.8 ± 11.8 in the L-carnitine group. It has been speculated that a shift in the energy source occurs from carbohydrate to lipid, in terms of an increase of oxygen demand. CONCLUSION: L-Carnitine supplementation might have some beneficial effects on the physical capacity of chronic hemodialysis patients due to the improvement of the lipid metabolism in the muscle.

9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(1): 89-91, 2013 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-23586232

RESUMO

The diffuse-reflectance FTIR spectroscopy (DRIFTS) and attenuated total reflection FTIR (ATR-FTIR) were used to study polygonum multi florum Thumb and its extracts. The result shows that when acetone is used as extraction agent, the contents of extracts in polygonum multi florum Thunb's phloem are highest, those in polygonum multi florum Thunb's xylem are the lowest. Compared with DRIFTS and ATR-FTIR, it can be found that there are some differences between polygonum multi florum Thunb and its extracts. There are two gentle absorption peaks at 3 576 and 3 147 cm(-1) respectively for polygonum multi florum Thunb, while there is a strong absorption peak at 3 351 cm(-1) for its extracts, showing that there may be more OH... active ingredients in polygonum multi florum Thunb's extracts. Meanwhile, polygonum multiflorum Thunb has strong absorption peaks at 931, 859, 766 and 709 cm(-1) respectively, while its extracts have no resembling absorption peaks. It also shows that the extracts are active ingredients.


Assuntos
Medicamentos de Ervas Chinesas/análise , Extratos Vegetais/química , Polygonum/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
10.
J Cell Physiol ; 227(6): 2363-70, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21826650

RESUMO

Small hepatocytes (SHs) are a subpopulation of hepatocytes that have high growth potential in culture and can differentiate into mature hepatocytes (MHs). The activin (Act)/follistatin (Fst) system critically contributes to homeostasis of cell growth in the normal liver. ActA and ActB consist of two disulfide-linked Inhibin (Inh)ß subunits, InhßA and InhßB, respectively. Fst binds to Act and blocks its bioactivity. In the present study we carried out the experiments to clarify how Fst regulates the proliferation of SHs. The gene expression was analyzed using DNA microarray analysis, reverse transcription-polymerase chain reaction (RT-PCR) and real-time PCR, and protein expression was examined by western blots, immunocytochemistry, and enzyme-linked immunosorbent assay. RT-PCR showed that Fst expression was high in SHs and low in MHs. Although the ActA expression was opposite to that of Fst, ActB expression was high in SHs and low in MHs and increased with time in culture. Fst protein was detected in the cytoplasm of SHs and secreted into the culture medium. ActB protein was also secreted into the medium. Although the exogenous administration of ActA and ActB apparently suppressed the proliferation of SHs, apoptosis of SHs was not induced by treatment with ActA or ActB. On the other hand, Fst treatment did not affect the colony formation of SHs but prevented the inhibitory effect of ActA. Neutralization by the anti-Fst antibody resulted in the suppression of DNA synthesis in SHs, and small hairpin RNA against Fst suppressed the expansion of SH colonies. In conclusion, Fst expression is necessary for the proliferation of SHs.


Assuntos
Proliferação de Células , Tamanho Celular , Folistatina/metabolismo , Hepatócitos/metabolismo , Fígado/metabolismo , Ativinas/metabolismo , Animais , Apoptose , Western Blotting , Diferenciação Celular , Células Cultivadas , Meios de Cultivo Condicionados/metabolismo , Replicação do DNA , Ensaio de Imunoadsorção Enzimática , Folistatina/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica , Imuno-Histoquímica , Fígado/citologia , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Interferência de RNA , Ratos , Ratos Endogâmicos F344 , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Transfecção
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(12): 3217-9, 2012 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-23427538

RESUMO

In-situ attenuated total reflection FTIR (in situ ATR-FTIR) was used for the dynamic research on the residual of pesticide. The in-situ characterization of dichlorvos and orthene on the tomatoes' surface shows that the dichlorvos has obvious volatility and its degradation amount is 80% 20 minutes after spraying. Meanwhile, the ATR-FTIR shows that the strong absorption peak of dichlorvos at 1 734 cm(-1) turns to negative peaks and the absorption peaks at 3 073 cm(-1) significantly abate. The absorption peaks at 1 277 cm(-1) become weak and red shift (30 cm(-1)) shows that the dichlorvos may be hydrolyzed to some extent. While the absorption peaks of orthene show no change 120 minute after spraying. It shows that the orthene is relatively stable.


Assuntos
Resíduos de Praguicidas/análise , Solanum lycopersicum/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Diclorvós/análise , Compostos Organotiofosforados/análise , Fosforamidas , Propriedades de Superfície , Volatilização
12.
Am J Pathol ; 175(6): 2362-71, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19893024

RESUMO

In galactosamine (GalN)-induced rat liver injury, hepatic stem/progenitor cells, small hepatocytes (SHs) and oval cells, transiently appear in the initial period of liver regeneration. To clarify the relationship between SHs and oval cells, CD44(+) and Thy1(+) cells were sorted from GalN-treated livers and used as candidates for SHs and oval cells, respectively. Some Thy1(+) cells isolated 3 days after GalN-treatment (GalN-D3) formed CD44(+) cell colonies, but those from GalN-D2 could form few. GeneChip (Affymetrix, Inc, Santa Clara, CA) analysis of the sorted cells and cultured Thy1(+) cells suggested that hepatocytic differentiation progressed in the order Thy1(+) (GalN-D3), Thy1(+) cell colony (Thy1-C), and CD44(+) (GalN-D4) cells. When Thy1(+), Thy1-C, and CD44(+) cells were transplanted into retrorsine/PH rat livers, they could proliferate to form hepatocytic foci. At 30 days after transplantation most cells forming the foci derived from CD44(+) cells possessed C/EBPalpha(+) nuclei, whereas only a few cells derived from Thy1-C showed this positivity. When Thy1(+) (GalN-D3) cells were cultured between collagen gels in medium with hepatocyte growth factor(+)/dexamethasone(-)/dimethyl sulfoxide(-), ducts/cysts consisting of biliary epithelial cells appeared, whereas with CD44(+) and Thy1(+) (GalN-D2) cells they did not. Taken together, these results indicate that the commitment of Thy1(+) cells to differentiate into hepatocytes or biliary epithelial cells may occur between Day 2 and Day 3. Furthermore, some Thy1(+) cells may differentiate into hepatocytes via CD44(+) SHs.


Assuntos
Sistema Biliar/citologia , Diferenciação Celular/fisiologia , Células Epiteliais/citologia , Hepatócitos/citologia , Regeneração Hepática/fisiologia , Antígenos Thy-1/metabolismo , Animais , Separação Celular , Doença Hepática Induzida por Substâncias e Drogas/patologia , Células Epiteliais/metabolismo , Citometria de Fluxo , Galactosamina/toxicidade , Hepatócitos/metabolismo , Receptores de Hialuronatos/metabolismo , Imuno-Histoquímica , Masculino , Microscopia Eletrônica de Transmissão , Análise de Sequência com Séries de Oligonucleotídeos , Ratos , Ratos Endogâmicos F344 , Células-Tronco/citologia , Células-Tronco/metabolismo
13.
Cell Transplant ; 17(10-11): 1221-30, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19181216

RESUMO

Rat small hepatocytes (SHs) are committed progenitor cells that can differentiate into mature hepatocytes and can selectively proliferate in serum-free medium when they are cultured on hyaluronic acid (HA)-coated dishes. In this study we examined the separation of human SHs from adult human livers. We obtained liver tissues from the resected liver of 16 patients who underwent hepatic resections. Extracted liver specimens were clearly separate from the tumor regions with sufficient margins. Hepatic cells were isolated using the modified method of two-step collagenase perfusion. A low-speed centrifugation was performed and cells in the supernatant were finally cultured on HA-coated dishes in serum-free DMEM/F12 medium including nicotinamide, EGF, and HGF. Small-sized hepatocytes selectively proliferated to form colonies and many colonies continued growing for more than 3 weeks. The average number of cells in a colony was 38.6 +/- 18.0, 79.0 +/- 54.0, and 101.5 +/- 115.7 at day 7, 14, and 21, respectively. About 0.04% of plated cells could form an SH colony. Immunocytochemistry showed that the cells forming a colony were positive for albumin, transferrin, keratin 8, and CD44. The results of RT-PCR showed that colony-forming cells expressed albumin, transferrin, alpha1-antitrypsin, fibrinogen, glutamine synthetase, many cytochrome P450s, and liver-enriched transcription factors (HNF3alpha, HNF4alpha, C/EBPalpha, and C/EBPbeta). Furthermore, the cells expressed not only the genes of hepatic differentiated functions but also those of both hepatic stem cell marker (Thy1.1, EpCAM, AFP) and SH marker (CD44, D6.1A, BRI3). Albumin secretion into culture medium was also observed. Our results demonstrate the existence of hepatocyte progenitor cells in human adult livers, and the cells can grow in a serum-free medium on HA-coated dishes. Human SHs may be a useful source for cell transplantation as well as pharmaceutical and toxicological investigations.


Assuntos
Proliferação de Células , Meios de Cultura Livres de Soro/farmacologia , Hepatócitos/fisiologia , Fígado/efeitos dos fármacos , Células-Tronco/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Albuminas/metabolismo , Técnicas de Cultura de Células , Células Cultivadas , Materiais Revestidos Biocompatíveis/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo , Feminino , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Ácido Hialurônico/farmacologia , Fígado/citologia , Fígado/enzimologia , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Manejo de Espécimes/métodos , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo
14.
Nat Protoc ; 2(5): 1197-205, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17546015

RESUMO

This protocol details a method of obtaining selectively proliferated hepatocyte progenitor cells using hyaluronic acid (HA)-coated dishes and serum-free medium. A small hepatocyte (SH) is a hepatocyte progenitor cell of adult livers and has many hepatic functions. When the rat SH begins to proliferate, CD44 is specifically expressed. To define the purification of SH, CD44 and cytokeratin 8 are used as marker proteins. The growth of SHs is faster on HA-coated dishes than on other extracellular matrix-coated ones. The use of both DMEM/F12 medium and HA-coated dishes allows the selective proliferation of SHs in culture. The purification of SHs is approximately 85% at day 10.


Assuntos
Técnicas de Cultura de Células/métodos , Proliferação de Células , Hepatócitos/citologia , Células-Tronco/citologia , Animais , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico , Queratina-8 , Ratos
15.
Int Immunol ; 16(12): 1701-9, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15477228

RESUMO

Dendritic cells (DCs) are potent antigen-presenting cells that play a pivotal role in the initiation of T cell-dependent immune responses. Immature DCs obtained from peripheral blood CD14+ monocytes by culture with granulocyte macrophage-colony stimulating factor (GM-CSF) and interleukin-4 (IL-4) differentiate into mature DCs upon stimulation with lipopolysaccharide (LPS). At least three families of mitogen-activated protein kinases (MAPKs), that is, extracellular signal-regulated kinases (ERK), c-Jun N-terminal kinases (JNK) and p38 MAPK, are involved in the DC maturation process. We report investigations of the role of JNK in the maturation of human monocyte-derived DCs. SP600125, a specific inhibitor of JNK, inhibited the LPS-induced up-regulation of CD80, CD83, CD86 and CD54, but augmented the up-regulation of HLA-DR. SP600125 slightly inhibited the down-regulation of FITC-dextran uptake during DC maturation. However, SP600125 did not affect the LPS induced up-regulation of allostimulatory capacity of DCs. SP600125 inhibited the release of IL-12 p70 and TNF-alpha from mature DCs. Although autologous T cells primed by the ovalbumin (OVA)-pulsed mature DCs produced IFN-gamma, but not IL-4, OVA-pulsed SP600125-treated mature DCs could initiate IL-4 production from autologous T cells. In contrast, a p38 MAPK inhibitor, SB203580, profoundly inhibited the phenotypic and functional maturation of DCs, while an ERK inhibitor, PD98059, had little or no effect. Taken together, the JNK signaling pathway appears to have a role that is distinct from the p38 MAPK and ERK cascades in the maturation process of DCs, and may be involved in the augmentation of Th2-prone T cell responses when it is suppressed.


Assuntos
Células Dendríticas/enzimologia , Fluoresceína-5-Isotiocianato/análogos & derivados , Proteínas Quinases JNK Ativadas por Mitógeno/fisiologia , Antracenos/farmacologia , Antígenos CD/metabolismo , Transporte Biológico/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Células Dendríticas/imunologia , Dextranos/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Flavonoides/farmacologia , Fluoresceína-5-Isotiocianato/metabolismo , Antígenos HLA-DR/metabolismo , Humanos , Imidazóis/farmacologia , Interleucina-12/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Monócitos/efeitos dos fármacos , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Subunidades Proteicas/metabolismo , Piridinas/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/fisiologia
16.
J Dermatol Sci ; 29(2): 97-103, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12088610

RESUMO

Propionibacterium acnes (P. acnes) causes an inflammatory acne that is characterized by massive neutrophilic infiltration. IL-8 is thought to play an important role in the pathophysiology of P. acnes, although the mechanisms by which P. acnes up-regulates the release of IL-8, a neutrophilic chemokine, from target cells is not well understood. In this study, we investigated the mechanisms through which heat-killed P. acnes induces IL-8 production in THP-1 cells (a human monocytic cell line). We found that P. acnes is able to directly induce IL-8 production and IL-8 mRNA expression in human monocytic cells in a dose- and time-dependent manner through a mechanism requiring transcription factor NF-kappaB activation. Additionally, P. acnes-induced IL-8 secretion was inhibited by roxithromycin, a macrolide antibiotic, and its inhibitory effect seemed to be partially associated with the inhibition of P. acnes-induced NF-kappaB activation. This is the first study to show that NF-kappaB activation is involved in the IL-8 production of monocytic cells stimulated by P. acnes.


Assuntos
Interleucina-8/biossíntese , Monócitos/metabolismo , Monócitos/microbiologia , NF-kappa B/fisiologia , Propionibacterium acnes/fisiologia , Antibacterianos/farmacologia , Linhagem Celular , Homeostase , Humanos , Interleucina-8/antagonistas & inibidores , Interleucina-8/genética , NF-kappa B/efeitos dos fármacos , RNA Mensageiro/metabolismo , Roxitromicina/farmacologia , Regulação para Cima
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