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1.
Asian J Surg ; 44(10): 1324-1325, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34548220

RESUMO

It is very necessary for patients with liver cancer to reasonably apply the prediction method of liver failure after hepatectomy before liver surgery. Liver surgeons can benefit greatly from clinical activities.


Assuntos
Insuficiência Hepática , Falência Hepática , Neoplasias Hepáticas , Hepatectomia/efeitos adversos , Humanos , Falência Hepática/etiologia , Neoplasias Hepáticas/cirurgia , Fatores de Risco
2.
Front Oncol ; 11: 700228, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34395268

RESUMO

Background: Hepatocellular carcinoma (HCC) is one of the most serious consequences of chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infection. This study sought to investigate long-term outcomes after liver resection for HCC among patients with HBV/HCV co-infection (HBV/HCV-HCC) compared with patients with HBV infection (HBV-HCC). Methods: Patients who underwent curative-intent liver resection for HCC were identified from a multicenter Chinese database. Using propensity score matching (PSM), patients with HBV/HCV-HCC were matched one-to-one to patients with HBV-HCC. Overall survival (OS) and recurrence-free survival (RFS) were compared between the two groups before and after PSM. Results: Among 2,467 patients identified, 93 (3.8%) and 2,374 (96.2%) patients had HBV/HCV-HCC and HBV-HCC, respectively. Compared with patients with HBV-HCC, patients with HBV/HCV-HCC were older, have poorer liver-related characteristics but better tumor-related characteristics. PSM created 88 pairs of patients with comparable liver- and tumor-related characteristics (all P > 0.2). In the PSM cohort, the 3- and 5-year RFS rates in patients with HBV/HCV-HCC were 48.3% and 38.9%, which were significantly poorer than patients with HBV-HCC (61.8% and 49.2%, P = 0.037). Meanwhile, the 3- and 5-year OS rates in patients with HBV/HCV-HCC were also poorer than patients with HBV-HCC (65.4% and 51.1% vs. 73.7% and 63.0%), with a difference close to be significant between them (P = 0.081). Conclusion: Comparing to patients with HBV-HCC, liver resection resulted in relatively poorer long-term surgical outcomes in patients with HBV/HCV-HCC.

3.
World J Clin Cases ; 9(21): 6067-6072, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34368328

RESUMO

BACKGROUND: Direct metagenomic next-generation sequencing (mNGS) of clinical samples is an effective method for the molecular diagnosis of infection. However, its role in the diagnosis of patients with acute respiratory distress syndrome (ARDS) of an unknown infectious etiology remains unclear. CASE SUMMARY: A 33-year-old man was admitted to our center for a cough and febrile sensation. Shortly after admission, the patient was diagnosed with ARDS and treated in the intensive care unit. Subsequently, chest computed tomography features suggested an infection. mNGS was performed and the results were indicative of an infection caused by adenovirus type 7. The patient recovered after receiving appropriate treatment. CONCLUSION: mNGS is a promising tool for the diagnosis of ARDS caused by infectious agents. However, further studies are required to develop strategies for incorporating mNGS into the current diagnostic process for the disease.

4.
Eur J Surg Oncol ; 47(10): 2551-2560, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33934940

RESUMO

BACKGROUND & AIMS: Postoperative morbidity following hepatectomy for hepatocellular carcinoma (HCC) is common and its impact on long-term oncological outcome remains unclear. This study aimed to investigate if postoperative morbidity impacts long-term survival and recurrence following hepatectomy for HCC. METHODS: The data from a multicenter Chinese database of curative-intent hepatectomy for HCC were analyzed, and independent risks of postoperative 30-day morbidity were identified. After excluding patients with postoperative early deaths (≤90 days), early (≤2 years) and late (>2 years) recurrence rates, overall survival (OS), and time-to-recurrence (TTR) were compared between patients with and without postoperative morbidity. RESULTS: Among 2,161 patients eligible for the study, 758 (35.1%) had postoperative 30-day morbidity. Multivariable logistic regression analysis showed that diabetes mellitus, obesity, Child-Pugh grade B, cirrhosis, and intraoperative blood transfusion were independent risks of postoperative morbidity. The rates of early and late recurrence among patients with postoperative morbidity were higher than those without (50.7% vs. 38.8%, P < 0.001; and 41.7% vs. 34.1%, P = 0.017). Postoperative morbidity was associated with decreased OS (median: 48.1 vs. 91.6 months, P < 0.001) and TTR (median: 19.8 vs. 46.1 months; P < 0.001). After adjustment of confounding factors, multivariable Cox-regression analyses revealed that postoperative morbidity was associated with a 27.8% and 18.7% greater likelihood of mortality (hazard ratio 1.278; 95% confidence interval: 1.126-1.451; P < 0.001) and recurrence (1.187; 1.058-1.331; P = 0.004). CONCLUSION: This large multicenter study provides strong evidence that postoperative morbidity adversely impacts long-term oncologic prognosis after hepatectomy for HCC. The prevention and management of postoperative morbidity may be oncologically important.

5.
Am J Surg ; 222(4): 751-758, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33741185

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) is common among adolescents and young adults (AYAs) in areas with endemic hepatitis B virus infection. We sought to characterize clinical features and long-term outcomes among AYAs versus older adults (OAs) who underwent HCC resection. METHODS: From a Chinese multicenter database, patients were categorized as AYA (aged 13-39 years) versus OA (aged ≥40 years). Patient clinical features, perioperative outcomes, overall survival (OS) and time-to-recurrence (TTR) were compared. Multivariable Cox-regression analyses were performed to identify the impact of age on OS and TTR. RESULTS: Among 1952 patients, 354(22.2%) were AYAs. AYAs were less likely to have cirrhosis yet were likely to have advanced tumor pathological characteristics than OAs. Postoperative morbidity and mortality were comparable. Compared with OAs, AYAs had a comparable OS but a decreased TTR. Multivariable analyses identified that young age (<40 years) was independently associated with poorer TTR. CONCLUSIONS: Compared with OAs, AYAs had a higher incidence of recurrence following liver resection among patients with HCC, suggesting that enhanced surveillance for postoperative recurrence may be required among AYAs.


Assuntos
Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/virologia , Hepatite B/epidemiologia , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/virologia , Adolescente , Adulto , Carcinoma Hepatocelular/mortalidade , China/epidemiologia , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Masculino , Recidiva Local de Neoplasia , Fatores de Risco , Taxa de Sobrevida
6.
Hepatol Int ; 15(2): 459-471, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33534082

RESUMO

BACKGROUND: Evidence-based decision-making is critical to optimize the benefits and mitigate futility associated with surgery for patients with malignancies. Untreated hepatocellular carcinoma (HCC) has a median survival of only 6 months. The objective was to develop and validate an individualized patient-specific tool to predict preoperatively the benefit of surgery to provide a survival benefit of at least 6 months following resection. METHODS: Using an international multicenter database, patients who underwent curative-intent liver resection for HCC from 2008 to 2017 were identified. Using random assignment, two-thirds of patients were assigned to a training cohort with the remaining one-third assigned to the validation cohort. Independent predictors of postoperative death within 6 months after surgery for HCC were identified and used to construct a nomogram model with a corresponding online calculator. The predictive accuracy of the calculator was assessed using C-index and calibration curves. RESULTS: Independent factors associated with death within 6 months of surgery included age, Child-Pugh grading, portal hypertension, alpha-fetoprotein level, tumor rupture, tumor size, tumor number and gross vascular invasion. A nomogram that incorporated these factors demonstrated excellent calibration and good performance in both the training and validation cohorts (C-indexes: 0.802 and 0.798). The nomogram also performed better than four other commonly-used HCC staging systems (C-indexes: 0.800 vs. 0.542-0.748). CONCLUSIONS: An easy-to-use online prediction calculator was able to identify patients at highest risk of death within 6 months of surgery for HCC. The proposed online calculator may help guide surgical decision-making to avoid futile surgery for patients with HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/cirurgia , Hepatectomia , Humanos , Neoplasias Hepáticas/cirurgia , Nomogramas , Estudos Retrospectivos
7.
Am J Surg ; 221(5): 1024-1032, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32951853

RESUMO

BACKGROUND: Prealbumin is a more sensitive serum biomarker in reflecting liver function and nutritional status than albumin, because of its shorter half-life and its characteristics that could hardly be affected by supplemental venous infusion of albumin or blood transfusion. This study aimed to identify whether preoperative prealbumin level was associated with postoperative mortality and morbidity after hepatic resection for patients with hepatocellular carcinoma (HCC). METHODS: From a Chinese multicenter database, patients who underwent hepatic resection for HCC were divided into the low and normal prealbumin groups by using 17 mg/dL as the cut-off level for serum prealbumin taken within a week before surgery. Using univariable and multivariable logistic regression analyses, independent predictors associated with postoperative 30-day and 90-day mortality, 30-day overall and major morbidity, and postoperative hepatic insufficiency were identified. RESULTS: Among 1356 patients, 409 (30.2%) had a low preoperative prealbumin level. Postoperative 30-day and 90-day mortality, and 30-day overall and major morbidity in the low prealbumin group were significantly higher than the normal prealbumin group (2.9% vs. 0.5%, 5.1% vs. 1.5%, 35.7% vs. 18.4%, and 14.4% vs. 6.5%, respectively, all P < 0.001). Multivariable analyses identified that preoperative prealbumin level, but not albumin level, was independently associated with postoperative 30-day mortality (OR: 3.486, 95% CI: 1.184-10.265), 90-day mortality (2.504, 1.219-5.145), 30-day overall morbidity (1.727, 1.302-2.292), 30-day major morbidity (1.770, 1.155-2.711) and postoperative hepatic insufficiency (1.967, 1.119-3.427). CONCLUSIONS: Preoperative prealbumin level could be used to predict postoperative morbidity and mortality for patients treated with hepatic resection for HCC.


Assuntos
Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Pré-Albumina/análise , Biomarcadores/sangue , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/virologia , Feminino , Hepatectomia/métodos , Hepatectomia/mortalidade , Hepatite B/complicações , Hepatite B/epidemiologia , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estado Nutricional , Valor Preditivo dos Testes , Período Pré-Operatório
8.
Cancer Manag Res ; 12: 5607-5618, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32753973

RESUMO

Background: With an increase in life expectancy and improvement of surgical safety, more elderly patients with hepatocellular carcinoma (HCC), even with large tumors, are now considered for hepatectomy. This study aimed to clarify the impact of age on short- and long-term outcomes after major hepatectomy (≥3 segments) for large HCC (≥5 cm). Patients and Methods: Using a multicenter database, patients who underwent curative-intent major hepatectomy for large HCC between 2006 and 2016 were identified. Postoperative morbidity and mortality, overall survival (OS) and recurrence-free survival (RFS) were compared between the elderly (≥65 years) and younger (<65 years) patients. Univariable and multivariable Cox-regression analyses were performed to identify the risk factors of OS and RFS in the entire and elderly cohorts, respectively. Results: Of 830 patients, 92 (11.1%) and 738 (88.9%) were elderly and younger patients, respectively. There were no significant differences in postoperative 30-day mortality and morbidity between the two groups (5.4% vs 2.6% and 43.5% vs 38.3%, both P>0.05). The 5-year OS and RFS rates in elderly patients were also comparable to younger patients (35.0% vs 33.2% and 20.0% vs 20.8%, both P>0.05). In the entire cohort, multivariable Cox-regression analyses identified that old age was not independently associated with OS and RFS. However, in the elderly cohort, preoperative alpha-fetoprotein level >400 µg/L, multiple tumors, macrovascular invasion and microvascular invasion were independently associated with decreased OS and RFS. Conclusion: Carefully selected elderly patients benefited from major hepatectomy for large HCC as much as younger patients, and their long-term prognosis was determined by preoperative alpha-fetoprotein level, tumor number and presence of macro- or micro-vascular invasion.

11.
Sci Rep ; 6: 32167, 2016 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-27571770

RESUMO

A synthetic monoketone analog of curcumin, termed 3, 5-bis (2-flurobenzylidene) piperidin-4-one (EF24), has been reported to inhibit the growth of a variety of cancer cells both in vitro and in vivo. However, whether EF24 has anticancer effects on cholangiocarcinoma (CCA) cells and the mechanisms remain to be investigated. The aim of our study was to evaluate the molecular mechanisms underlying the anticancer effects of EF24 on CCA tumor growth and metastasis. Cell proliferation, apoptosis, migration, invasion, tumorigenesis and metastasis were examined. EF24 exhibited time- and dose-dependent inhibitory effects on HuCCT-1, TFK-1 and HuH28 human CCA cell lines. EF24 inhibited CCA cell proliferation, migration, and induced G2/M phase arrest. EF24 induced cell apoptosis along with negative regulation of NF-κB- X-linked inhibitor of apoptosis protein (XIAP) signaling pathway. XIAP inhibition by lentivirus mediated RNA interference enhanced EF24-induced apoptosis, while XIAP overexpression reduced it in CCA cells. In vivo, EF24 significantly suppressed the growth of CCA tumor xenografts and tumor metastasis while displaying low toxicity levels. Our findings indicate that EF24 is a potent antitumor agent that inhibits tumor growth and metastasis by inhibiting NF-κB dependent signaling pathways. EF24 may represent a novel approach for CCA treatment.


Assuntos
Compostos de Benzilideno/farmacologia , Colangiocarcinoma/tratamento farmacológico , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , NF-kappa B/metabolismo , Proteínas de Neoplasias/metabolismo , Piperidonas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Colangiocarcinoma/genética , Colangiocarcinoma/metabolismo , Colangiocarcinoma/patologia , Pontos de Checagem da Fase G2 do Ciclo Celular/genética , Humanos , Pontos de Checagem da Fase M do Ciclo Celular/genética , NF-kappa B/genética , Metástase Neoplásica , Proteínas de Neoplasias/genética , Transdução de Sinais/genética
12.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 25(3): 140-4, 2013 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-23656765

RESUMO

OBJECTIVE: To investigate the damage to endothelial cells incubated in high concentration of glucose challenged by lipopolysaccharide (LPS), and the likely mechanisms of injury. METHODS: Human pulmonary microvascular endothelial cells (PMVECs) were divided into the following groups: normal glucose group (NG), normal glucose + LPS stimulation group (NGL), high glucose stimulation group (HG), and high glucose + LPS stimulation group (HGL). The cells were incubated with normal glucose (5.5 mmol/L, contained 10% calf serum) or high glucose (33 mmol/L) for 5 days to form a monolayer of cells before LPS stimulation (10 mg/L) for 24 hours. The microfilaments (F-actin) were investigated by immuno-fluorescence, and the number and size change in fenestrae were examined by scanning electron microscopy. The permeability of vascular endothelial cell was assessed by trans-PMVEC horseradish peroxidase (HRP) flux. Western blotting was used to determine the expressions of dimethylarginine dimethylaminohydrolase 2 (DDAH2), inducible nitricoxide synthase (iNOS) and endothelial nitricoxide synthase (eNOS). Nitric oxide (NO) was assessed by Griess method. RESULTS: When stimulated with LPS, cells incubated with high glucose showed obvious microfilament rearrangement, a larger average diameter and increased number of F-actin, as well as higher HRP permeability on the hyperglycemic PMVECs compared with PMVECs cultured with normal glucose [(53.62±6.70)% vs. (23.63±3.92)%, P<0.01]. Furthermore, high glucose down-regulated DDAH2 expression (arbitrary units, AU, 0.33±0.08 vs. 0.77±0.14 , P<0.01) and up-regulated LPS-stimulated iNOS production (1.40±0.29 vs. 1.04±0.09, P<0.01), as well as increased LPS-stimulated nitrite/nitrate and stable NO end products compared with normal (20.36±2.25 µmol/L vs. 7.99±0.33 µmol/L, P<0.01) and reduction of eNOS levels was observed (0.67±0.09 vs. 0.91±0.17, P<0.05). CONCLUSION: It demonstrated that, in vitro high glucose deteriorate LPS-stimulated F-actin rearrangement and hyperpermeability of an endothelial monolayer, and the worsened imbalance of the NO pathway may lead to endothelial damage in microcirculation.


Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/citologia , Glucose/farmacologia , Lipopolissacarídeos/farmacologia , Actinas/metabolismo , Amidoidrolases/metabolismo , Células Cultivadas , Células Endoteliais/metabolismo , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Glucose/administração & dosagem , Humanos , Microcirculação , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo
13.
Hepatogastroenterology ; 59(118): 1951-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22819915

RESUMO

Liver resection has been established currently as an effective and standard treatment for patients suffering from both benign and malignant hepatobiliary diseases. Although substantial improvement in perioperative mortality rate and morbidity resulting from appropriate candidates selection, advanced surgical techniques and enhanced perioperative care, hepatectomy is still burdened by about 5% mortality rate and some lethal postoperative complications, especially postoperative liver insufficiency and failure. Various approaches have been advocated to minimize stress and insult on patients due to operative procedures. It becomes important to preserve remnant hepatic function as much as possible to improve the outcome of hepatectomy. Minimally invasive concept and fast track surgery are crucial breakthrough in the natural history of surgery and have been employed in liver resection. To safely and accurately perform hepatic resection, owing to our experiences with recent advances in surgical techniques and perioperative administration for liver resection, a novel strategy, "precise hepatectomy" originating from minimally invasive surgery has been developed, which includes precise preoperative planning, sophisticated intraoperative techniques and careful postoperative management. This strategy is characteristic by involvement of minimally invasive concept in overall therapy, from preoperative assessment to postoperative care, optimization of a series of advanced techniques and proper employment of surgical instruments in light of actual individual information. However, further prospective studies, especially randomized controlled trials in high volume centers, remain essential to compare the safety and therapeutic efficacies between precise hepatectomy and conventional surgical procedures.


Assuntos
Hepatectomia/métodos , Hepatectomia/efeitos adversos , Hepatectomia/mortalidade , Humanos , Procedimentos Cirúrgicos Minimamente Invasivos , Complicações Pós-Operatórias/etiologia , Medição de Risco , Fatores de Risco , Resultado do Tratamento
14.
Exp Biol Med (Maywood) ; 237(4): 352-61, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22550337

RESUMO

The tumor-suppressor ING3 has been shown to be involved in tumor transcriptional regulation, apoptosis and the cell cycle. Some studies have demonstrated that ING3 is dysregulated in several types of cancers. However, the expression and function of ING3 in human hepatocellular carcinoma (HCC) remains unclear. The aim of this study is to investigate ING3 expression in hepatic tumors and its clinical relevance in hepatic cancer. The expression of ING3 protein was examined in 120 dissected HCC tissues and 47 liver tissues adjacent to the tumor by immunohistochemical assays and confirmed by Western blot analysis in 20 paired frozen tumor and non-tumor liver tissues. The relationship between ING3 staining and clinico-pathological characteristics of HCC was further analyzed. The mRNA expression of ING3 in the dissected tissues was also analyzed by reverse transcriptase polymerase chain reaction (RT-PCR) and realtime PCR. Both mRNA and protein concentrations of ING3 were found to be downregulated in the majority of HCC tumors in comparison with matched non-tumor hepatic tissues. Analysis of the relationship between ING3 staining and clinico-pathological characteristics of HCC showed that the low expression of ING3 protein is correlated with more aggressive behavior of the tumor. Kaplan-Meier curves demonstrated that patients with a low expression of ING3 have a significantly increased risk of shortened survival time. In addition, multivariate analysis suggested that the level of ING3 expression may be an independent prognostic factor. Our findings indicate that ING3 may be an important marker for human hepatocellular carcinoma progression and prognosis, as well as a potential therapeutic target.


Assuntos
Carcinoma Hepatocelular/genética , Proteínas de Homeodomínio/genética , Neoplasias Hepáticas/genética , Adulto , Idoso , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Feminino , Genes Supressores de Tumor , Proteínas de Homeodomínio/metabolismo , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Supressoras de Tumor
15.
J Clin Invest ; 122(4): 1306-15, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22426212

RESUMO

Mechanical hyperalgesia is a common and potentially disabling complication of many inflammatory and neuropathic conditions. Activation of the enzyme PKCε in primary afferent nociceptors is a major mechanism that underlies mechanical hyperalgesia, but the PKCε substrates involved downstream are not known. Here, we report that in a proteomic screen we identified the NaV1.8 sodium channel, which is selectively expressed in nociceptors, as a PKCε substrate. PKCε-mediated phosphorylation increased NaV1.8 currents, lowered the threshold voltage for activation, and produced a depolarizing shift in inactivation in wild-type - but not in PKCε-null - sensory neurons. PKCε phosphorylated NaV1.8 at S1452, and alanine substitution at this site blocked PKCε modulation of channel properties. Moreover, a specific PKCε activator peptide, ψεRACK, produced mechanical hyperalgesia in wild-type mice but not in Scn10a-/- mice, which lack NaV1.8 channels. These studies demonstrate that NaV1.8 is an important, direct substrate of PKCε that mediates PKCε-dependent mechanical hyperalgesia.


Assuntos
Hiperalgesia/etiologia , Proteína Quinase C-épsilon/fisiologia , Processamento de Proteína Pós-Traducional , Células Receptoras Sensoriais/fisiologia , Canais de Sódio/fisiologia , Potenciais de Ação , Substituição de Aminoácidos , Animais , Células Cultivadas/efeitos dos fármacos , Gânglios Espinais/citologia , Hiperalgesia/enzimologia , Ativação do Canal Iônico , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação de Sentido Incorreto , Canal de Sódio Disparado por Voltagem NAV1.8 , Mutação Puntual , Proteína Quinase C-épsilon/análise , Proteína Quinase C-épsilon/genética , Ratos , Células Receptoras Sensoriais/enzimologia , Sódio/metabolismo , Canais de Sódio/análise , Canais de Sódio/química , Canais de Sódio/deficiência , Canais de Sódio/genética , Estresse Mecânico , Especificidade por Substrato
16.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 22(9): 528-32, 2010 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-20854731

RESUMO

OBJECTIVE: To determine the activation status of p38 mitogen-activated protein kinase (p38MAPK)/nuclear factor-ΚB (NF-ΚB) in coagulation disorders due to endothelial injury induced by sepsis. METHODS: Human umbilical vein endothelial cells (HUVECs) were exposed to plasma obtained from 22 patients suffering from sepsis. Plasma was also obtained from 8 healthy individuals to serve as negative control, and tumor necrosis factor-α (TNF-α) was used as positive control. Phosphorylation and activity of p38MAPK and NF-ΚB were determined with enzyme-linked immunosorbent assay (ELISA), Western blotting, and immunofluorescence assay. RESULTS: The level of TNF-α (ng/L) in sepsis plasma was significantly higher than that in healthy plasma (155.68±89.74 vs. 5.00±0.47, P <0.01). Compared with healthy plasma in 20% concentration it was found when HUVECs were treated with sepsis plasma in 20% concentration, tissue factor (TF, µg/L) reached the peak at 180 minutes (5.87±0.14 vs. 1.25±0.11, P <0.01), von Willebrand factor (vWF, µg/L) reached the peak at 120 minutes (9.59±0.07 vs. 3.59±0.06, P <0.01), then they began to decline. When HUVECs were treated with sepsis plasma in 20% concentration increased phosphorylation and activity of p38MAPK and NF-ΚB, phosphorylation of p38MAPK occurred before phosphorylation of NF-ΚB (2 minutes vs. 5 minutes). When the inhibitor of p38MAPK (SB239063) was added, NF-ΚB phosphorylation (activation) and NF-ΚB nuclear translocation were inhibited. CONCLUSION: This study demonstrates that p38MAPK/NF-ΚB transduction pathway plays an important role in septic coagulopathy.


Assuntos
Células Endoteliais da Veia Umbilical Humana/metabolismo , NF-kappa B/metabolismo , Sepse/metabolismo , Transdução de Sinais , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Estudos de Casos e Controles , Células Cultivadas , Humanos , Fosforilação , Sepse/fisiopatologia , Fator de Necrose Tumoral alfa/sangue
17.
J Neurochem ; 109(4): 981-94, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19519772

RESUMO

Our previous work suggested that collapsing the Na(+) gradient and membrane potential converts the dopamine (DA) transporter (DAT) to an inward-facing conformation with a different substrate binding profile. Here, DAT expressing human embryonic kidney 293 cells were permeabilized with digitonin, disrupting ion/voltage gradients and allowing passage of DAT substrates. The potency of p-tyramine and other non-catechols (d-amphetamine, beta-phenethylamine, MPP(+)) in inhibiting cocaine analog binding to DAT in digitonin-treated cells was markedly weakened to a level similar to that observed in cell-free membranes. In contrast, the potency of DA and another catechol, norepinephrine, was not significantly changed by the same treatment, whereas epinephrine showed only a modest reduction. These findings suggest that catechol substrates interact symmetrically with both sides of DAT and non-catechol substrates, favoring binding to outward-facing transporter. In the cocaine analog binding assay, the mutant W84L displayed enhanced intrinsic binding affinity for substrates in interacting with both outward- and inward-facing states; D313N showed wild-type-like symmetric binding; but D267L and E428Q showed an apparent improvement in the permeation pathway from the external face towards the substrate site. Thus, the structure of both substrate and transporter play a role in the sidedness and mode of interaction between them.


Assuntos
Catecóis/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/química , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Sítios de Ligação , Linhagem Celular , Digitonina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/genética , Humanos , Cinética , Modelos Moleculares , Mutação , Permeabilidade , Ligação Proteica , Conformação Proteica , Especificidade por Substrato , Zinco/farmacologia
18.
Cell Res ; 18(7): 768-79, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18574501

RESUMO

The interaction of mu-opioid receptor (MOPr) with the neuronal membrane glycoprotein M6a is known to facilitate MOPr endocytosis in human embryonic kidney 293 (HEK293) cells. To further study the role of M6a in the post-endocytotic sorting of MOPr, we investigated the agonist-induced co-internalization of MOPr and M6a and protein targeting after internalization in HEK293 cells that co-expressed HA-tagged MOPr and Myc-tagged M6a. We found that M6a, MOPr, and Rab 11, a marker for recycling endosomes, co-localized in endocytotic vesicles, indicating that MOPr and M6a are primarily targeted to recycling endosomes after endocytosis. Furthermore, co-expression of M6a augmented the post-endocytotic sorting of delta-opioid receptors into the recycling pathway, indicating that M6a might have a more general role in opioid receptor post-endocytotic sorting. The enhanced post-endocytotic sorting of MOPr into the recycling pathway was accompanied by a decrease in agonist-induced receptor down-regulation of M6a in co-expressing cells. We tested the physiological relevance of these findings in primary cultures of cortical neurons and found that co-expression of M6a markedly increased the translocation of MOPrs from the plasma membrane to intracellular vesicles at steady state and significantly enhanced both constitutive and agonist-induced receptor endocytosis. In conclusion, our results strongly indicate that M6a modulates MOPr endocytosis and post-endocytotic sorting and has an important role in receptor regulation.


Assuntos
Endocitose , Metiltransferases/metabolismo , Receptores Opioides mu/metabolismo , Linhagem Celular , Regulação para Baixo , Humanos , Glicoproteínas de Membrana/análise , Glicoproteínas de Membrana/metabolismo , Metiltransferases/análise , Neurônios , Transporte Proteico , Receptores Opioides mu/análise , Vesículas Transportadoras/química , Proteínas rab de Ligação ao GTP/análise , Proteínas rab de Ligação ao GTP/metabolismo
19.
J Neurochem ; 104(4): 1132-43, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17986216

RESUMO

Agonist-induced internalization of G protein-coupled receptors (GPCRs) is an important mechanism for regulating signaling transduction of functional receptors at the plasma membrane. We demonstrate here that both caveolae/lipid-rafts- and clathrin-coated-pits-mediated pathways were involved in agonist-induced endocytosis of the cannabinoid type 1 receptor (CB1R) in stably transfected human embryonic kidney (HEK) 293 cells and that the internalized receptors were predominantly sorted into recycling pathway for reactivation. The treatment of CB1 receptors with the low endocytotic agonist Delta9-THC induced a faster receptor desensitization and slower resensitization than the high endocytotic agonist WIN 55,212-2. In addition, the blockade of receptor endocytosis or recycling pathway markedly enhanced agonist-induced CB1 receptor desensitization. Furthermore, co-expression of phospholipase D2, an enhancer of receptor endocytosis, reduced CB1 receptor desensitization, whereas co-expression of a phospholipase D2 negative mutant significantly increased the desensitization after WIN 55,212-2 treatment. These findings provide evidences for the importance of receptor endocytosis in counteracting CB1 receptor desensitization by facilitating receptor reactivation. Moreover, in primary cultured neurons, the low endocytotic agonist Delta9-THC or anandamide exhibited a greater desensitization of endogenous CB1 receptors than the high endocytotic agonist WIN 55,212-2, CP 55940 or 2-arachidonoyl glycerol, indicating that cannabinoids with high endocytotic efficacy might cause reduced development of cannabinoid tolerance to some kind cannabinoid-mediated effects.


Assuntos
Canabinoides/metabolismo , Canabinoides/farmacologia , Receptor CB1 de Canabinoide/antagonistas & inibidores , Receptor CB1 de Canabinoide/metabolismo , Animais , Benzoxazinas/metabolismo , Benzoxazinas/farmacologia , Linhagem Celular , Células Cultivadas , Endocitose/efeitos dos fármacos , Endocitose/fisiologia , Humanos , Morfolinas/metabolismo , Morfolinas/farmacologia , Naftalenos/metabolismo , Naftalenos/farmacologia , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Transporte Proteico/efeitos dos fármacos , Transporte Proteico/fisiologia , Ratos , Ratos Sprague-Dawley , Receptor CB1 de Canabinoide/agonistas , Fatores de Tempo
20.
J Biol Chem ; 282(30): 22239-47, 2007 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-17548356

RESUMO

Using a yeast two-hybrid screen, the neuronal membrane glycoprotein M6a, a member of the proteolipid protein family, was identified to be associated with the mu-opioid receptor (MOPr). Bioluminescence resonance energy transfer and co-immunoprecipitation experiments confirmed that M6a interacts agonist-independently with MOPr in human embryonic kidney 293 cells co-expressing MOPr and M6a. Co-expression of MOPr with M6a, but not with M6b or DM20, exists in many brain regions, further supporting a specific interaction between MOPr and M6a. After opioid treatment M6a co-internalizes and then co-recycles with MOPr to cell surface in transfected human embryonic kidney 293 cells. Moreover, the interaction of M6a and MOPr augments constitutive and agonist-dependent internalization as well as the recycling rate of mu-opioid receptors. On the other hand, overexpression of a M6a-negative mutant prevents mu-opioid receptor endocytosis, demonstrating an essential role of M6a in receptor internalization. In addition, we demonstrated the interaction of M6a with a number of other G protein-coupled receptors (GPCRs) such as the delta-opioid receptor, cannabinoid receptor CB1, and somatostatin receptor sst2A, suggesting that M6a might play a general role in the regulation of certain GPCRs. Taken together, these data provide evidence that M6a may act as a scaffolding molecule in the regulation of GPCR endocytosis and intracellular trafficking.


Assuntos
Glicoproteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptores Opioides mu/metabolismo , Animais , Linhagem Celular , Endocitose , Transferência Ressonante de Energia de Fluorescência , Imuno-Histoquímica , Hibridização In Situ , Cinética , Glicoproteínas de Membrana/genética , Reação em Cadeia da Polimerase , Ratos , Receptores Opioides mu/genética , Proteínas Recombinantes/metabolismo , Transfecção
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