Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
1.
Sensors (Basel) ; 24(7)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38610323

RESUMO

The mature processes of metal oxide semiconductors (MOS) have attracted considerable interest. However, the low sensitivity of metal oxide semiconductor gas sensors is still challenging, and constrains its practical applications. Bimetallic nanoparticles are of interest owing to their excellent catalytic properties. This excellent feature of bimetallic nanoparticles can solve the problems existing in MOS gas sensors, such as the low response, high operating temperature and slow response time. To enhance acetone sensing performance, we successfully synthesized Au-Pd/ZnO nanorods. In this work, we discovered that Au-Pd nanoparticles modified on ZnO nanorods can remarkably enhance sensor response. The Au-Pd/ZnO gas sensor has long-term stability and an excellent response/recovery process. This excellent sensing performance is attributed to the synergistic catalytic effect of bimetallic AuPd nanoparticles. Moreover, the electronic and chemical sensitization of noble metals also makes a great contribution. This work presents a simple method for preparing Au-Pd/ZnO nanorods and provides a new solution for the detection of acetone based on metal oxide semiconductor.

2.
Molecules ; 29(7)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38611936

RESUMO

Efficient sensors for toluene detecting are urgently needed to meet people's growing demands for both environment and personal health. Metal oxide semiconductor (MOS)-based sensors have become brilliant candidates for the detection of toluene because of their superior performance over gas sensing. However, gas sensors based on pure MOS have certain limitations in selectivity, operating temperature, and long-term stability, which hinders their further practical applications. Noble metals (including Ag, Au, Pt, Pd, etc.) have the ability to enhance the performance of MOS-based sensors via surface functionalization. Herein, ZnO nanoflowers (ZNFs) modified with bimetallic AuPt are prepared for toluene detection through hydrothermal method. The response of a AuPt@ZNF-based gas sensor can reach 69.7 at 175 °C, which is 30 times, 9 times, and 10 times higher than that of the original ZNFs, Au@ZNFs, and Pt@ZNFs, respectively. Furthermore, the sensor also has a lower optimal operating temperature (175 °C), good stability (94% of previous response after one month), and high selectivity towards toluene, which is the result of the combined influence of the electronic and chemical sensitization of noble metals, as well as the unique synergistic effect of the AuPt alloy. In summary, AuPt@ZNF-based sensors can be further applied in toluene detection in practical applications.

3.
Artigo em Inglês | MEDLINE | ID: mdl-31485245

RESUMO

OBJECTIVE: To investigate the effect of Da-Cheng-Qi decoction (DCQD) on treating intestinal injury in rats with severe acute pancreatitis (SAP), based on the Janus kinase 2 (JAK2)/signal transducers and transcription 3 (STAT3) signaling pathway. METHODS: Rats were randomly divided into the SAP group, SAP + ruxolitinib (JAK2 inhibitor) group, SAP + Stattic (STAT3 inhibitor) group, SAP + DCQD group, and sham operation group. They were further divided into 3-hour, 6-hour, 12-hour, and 18-hour subgroups. Levels of amylase and the inflammatory cytokines tumor necrosis factor-α, interleukin 6, interleukin 10, and interleukin 4 in plasma were tested. The messenger ribonucleic acid (mRNA) expression of JAK2 and STAT3 and the protein expression of phosphorylated JAK2 (p-JAK2) and phosphorylated STAT3 (p-STAT3) in the pancreas and terminal ileum tissues were examined. RESULTS: Rats with SAP had severe changes in plasma levels of amylase and inflammatory cytokines and showed an overexpression of JAK2 mRNA, STAT3 mRNA, p-JAK2 protein, and p-STAT3 protein in the pancreas and terminal ileum. The events could be downregulated by treatment with DCQD, JAK2 inhibitor, and STAT3 inhibitor. CONCLUSIONS: In rats with SAP, DCQD ameliorated inflammatory cytokines and intestinal injury, which may be closely associated with the inhibition of the JAK2/STAT3 signaling pathway.

4.
Langenbecks Arch Surg ; 402(5): 831-840, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28612115

RESUMO

PURPOSE: Pancreatoduodenectomy is the most common operative procedure performed for distal bile duct carcinoma. Data on outcome after surgery for this rare malignancy is scarce, especially from western countries. The purpose of this study is to explore the prognostic factors and outcome after pancreatoduodenectomy for distal bile duct carcinoma. METHODS: Patients receiving pancreatoduodenectomy for distal bile duct carcinoma were identified from institutional databases of five German and one Russian academic centers for pancreatic surgery. Univariable and multivariable general linear model, Kaplan-Meier method, and Cox regression were used to identify prognostic factors for postoperative mortality and overall survival. RESULTS: N = 228 patients operated from 1994 to 2015 were included. Reoperation (OR 5.38, 95%CI 1.51-19.22, p = 0.010), grade B/C postpancreatectomy hemorrhage (OR 3.73, 95%CI 1.13-12.35, p = 0.031), grade B/C postoperative pancreatic fistula (OR 4.29, 95%CI 1.25-14.72, p = 0.038), and advanced age (OR 4.00, 95%CI 1.12-14.03, p = 0.033) were independent risk factors for in-hospital mortality in multivariable analysis. Median survival was 29 months, 5-year survival 27%. Positive resection margin (HR 2.07, 95%CI 1.29-3.33, p = 0.003), high tumor grade (HR 1.71, 95%CI 1.13-2.58, p = 0.010), lymph node (HR 1.68, 95%CI 1.13-2.51, p = 0.011), and distant metastases (HR 2.70, 95%CI 1.21-5.58, p = 0.014), as well as severe non-fatal postoperative complications (HR 1.64, 95%CI 1.04-2.58, p = 0.033) were independent negative prognostic factors for survival in multivariable analysis. CONCLUSION: Distant metastases and positive resection margin are the strongest negative prognostic factors for survival after pancreatoduodenectomy for distal bile duct carcinoma; thus, surgery with curative intent is only warranted in patients with local disease, where R0 resection is feasible.


Assuntos
Neoplasias dos Ductos Biliares/cirurgia , Pancreaticoduodenectomia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/patologia , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/cirurgia , Prognóstico , Reoperação , Estudos Retrospectivos , Federação Russa , Taxa de Sobrevida , Resultado do Tratamento
5.
Surg Today ; 47(3): 271-279, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27236779

RESUMO

PURPOSE: To assess the available evidence on the prognostic factors for the 5-year survival for patients with distal cholangiocarcinoma (DCC) following surgical resection. METHODS: We performed a comprehensive search of abstracts included in databases where relevant studies were published between January 2000 and August 2015. Risk ratios (RRs), 95 % confidence intervals (95 % CIs), and random-effects model were calculated using RevMan 5.3 software. RESULTS: A total of 23 observational studies involving 2063 patients with DCC were analyzed. The meta-analysis showed that postoperative adjuvant chemotherapy was not confirmed as a prognostic factor, with similar 5-year survival rates between those receiving and not receiving chemotherapy (RR 0.71; 95 % CI 0.21-2.36; P = 0.57). Perineural invasion (RR 0.51; 95 % CI 0.40-0.64; P < 0.00001), lymph node metastasis (RR 0.51; 95 % CI 0.38-0.70; P < 0.0001), positive resection margin status (RR 2.11; 95 % CI 1.36-3.30; P = 0.001), and not-well-differentiated adenocarcinoma (RR 1.77; 95 % CI 1.39-2.25; P < 0.00001) were associated with shorter survival. CONCLUSIONS: Perineural invasion, lymph node metastasis, resection margin status, and tumor differentiation were the significant prognostic factors for the 5-year survival.


Assuntos
Neoplasias dos Ductos Biliares/mortalidade , Neoplasias dos Ductos Biliares/cirurgia , Colangiocarcinoma/mortalidade , Colangiocarcinoma/cirurgia , Idoso , Neoplasias dos Ductos Biliares/patologia , Quimioterapia Adjuvante , Colangiocarcinoma/patologia , Feminino , Humanos , Metástase Linfática , Masculino , Margens de Excisão , Pessoa de Meia-Idade , Invasividade Neoplásica , Neoplasias de Tecido Nervoso/patologia , Prognóstico , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
6.
Surg Today ; 45(8): 1009-17, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25410475

RESUMO

PURPOSE: To investigate the relationship between the APACHE II score and the immunity of patients with severe acute pancreatitis. METHODS: Clinical data were collected from 88 patients with acute pancreatitis, divided into four groups according to the severity of the disease. C-reactive protein (CRP), tumor necrosis factor-α, interleukin-6, interleukin-10, interleukin-4 and endotoxin (ET) in serum were measured on admission and then on days 3, 5, and 7. RESULTS: The incidence of local complications and multiple organ dysfunction syndrome increased with a higher APACHE II score. The CRP levels were increased significantly on day 3 in all four groups, but remained high only in the extremely severe group. In the mild and moderate groups, the pro-/anti-inflammatory cytokines peaked on day 3 and then decreased slowly. In the severe and extremely severe groups, the proinflammatory cytokines levels peaked on days 3 and 5, and then decreased rapidly. The antiinflammatory cytokines increased progressively on days 3, 5 and 7. The ET levels peaked significantly and then decreased slowly in the mild, moderate and severe groups, but remained high in the extremely severe group. CONCLUSIONS: An APACHE II score of 16 or higher is predictive of more local and systemic complications, excessive immune response, and premature immunosuppression.


Assuntos
Pancreatite/imunologia , APACHE , Doença Aguda , Adulto , Idoso , Biomarcadores/sangue , Proteína C-Reativa/análise , Endotoxinas/sangue , Feminino , Humanos , Hospedeiro Imunocomprometido , Mediadores da Inflamação/sangue , Interleucina-10/sangue , Interleucina-4/sangue , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Fator de Necrose Tumoral alfa/sangue
7.
Langenbecks Arch Surg ; 398(6): 817-23, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23695769

RESUMO

PURPOSE: The aim of our study was to evaluate the safety and effectiveness of early enteral nutrition (EN) for patients after pancreatoduodenectomy (PD). METHODS: We performed a comprehensive search of abstracts in the MEDLINE database, OVID database, Springer database, the Science Citation Index, and the Cochrane Library database. Published data of randomized clinical trials (RCTs) comparing the clinically relevant outcomes of early EN and other nutritional routes for patients after PD were analyzed. The analyzed outcome variables included gastroparesis, intra-abdominal complications (gastroparesis excluded), mortality, infection, and postoperative hospital stay. The Cochrane Collaboration's RevMan 5.1 software was used for statistical analysis. RESULTS: Four RCTs published in 2000 or later were included in this meta-analysis, in which 246 patients underwent early EN and 238 patients underwent other nutritional routes following PD. In the combined results of early EN versus other nutritional routes, no significant difference could be found in gastroparesis (odds ratio (OR), 0.89; 95 % CI, 0.36-2.18; P = 0.79), intra-abdominal complications (gastroparesis excluded) (OR, 0.82; 95 % CI, 0.53-1.26; P = 0.37), mortality (OR, 0.43; 95 % CI, 0.11-1.62; P = 0.21), infection (OR, 0.55; 95 % CI, 0.29-1.07; P = 0.08), postoperative hospital stay (mean difference, -0.93; 95 % CI, -6.51 to 4.65; P = 0.74). CONCLUSIONS: Current RCTs suggests that early EN appears safe and tolerated for patients after PD, but does not show advantages in infection and postoperative hospital stay.


Assuntos
Nutrição Enteral/métodos , Pancreaticoduodenectomia/métodos , Segurança do Paciente , Cuidados Pós-Operatórios/métodos , Medicina Baseada em Evidências , Feminino , Humanos , Tempo de Internação , Masculino , Pancreaticoduodenectomia/mortalidade , Prognóstico , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento
8.
Inflamm Res ; 61(7): 743-8, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22466614

RESUMO

OBJECTIVES: To observe immune system changes in patients with secondary infection from severe acute pancreatitis (SAP). METHODS: Seventy-nine patients were recruited. The percentages of CD4+, CD8+, natural killer (NK), HLA-DR+ cells and B lymphocytes, and the CD4+/CD8+ ratio, were determined. In addition, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-10 (IL-10), and interleukin-4 (IL-4) serum levels were determined on days 1, 7, 14, and 28. RESULTS: Fifteen patients had a secondary infection. The immune response of the infected group was quite different from the non-infected group, with a higher percentage of CD4+ and HLA-DR+ cells on days 1, 7, 14 and 28, a higher percentage of CD8+ and NK cells on days 14 and 28, a reduced CD4+/CD8+ ratio, and a reduction in B lymphocytes. The cytokine levels in the infected group were different from the non-infected group, with a rise in TNF-α and IL-6 through the first 2 weeks, but dropping at 1 month. IL-10 and IL-4 increased initially, but then dropped over the next 3 weeks. CONCLUSIONS: An early excessive immune response followed by a subsequent immune deficiency is closely related to secondary SAP infection.


Assuntos
Coinfecção/imunologia , Leucócitos Mononucleares/imunologia , Pancreatite/imunologia , Coinfecção/sangue , Coinfecção/complicações , Citocinas/sangue , Antígenos HLA-DR/imunologia , Humanos , Contagem de Linfócitos , Pancreatite/sangue , Pancreatite/complicações
9.
Inflammation ; 34(1): 36-42, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20405190

RESUMO

To investigate patients with severe acute pancreatitis (SAP) by dynamic levels of pro-/anti-inflammatory cytokines and endotoxin (ET) in plasma and the relationship between immunity and infection, organ dysfunction. Seventy-two patients with SAP were recruited. The ET, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-10 (IL-10), and interleukin-4 (IL-4) were determined on admission and days 3, 7, and 14. For comparison, patients were analyzed through infection group versus non-infection group, multiple organ dysfunction syndrome (MODS) group versus non-MODS group. There were sixteen patients with secondary infection, twenty-two with MODS, and nine deaths. The infection group had higher levels of ET than the non-infection group on days 3 and 7. The dynamic cytokine levels of patients in the MODS group were unanimous with those outcomes in the infection group. The levels of cytokines in the infection group were different from the non-infection group, with more levels of TNF-α, IL-6 on days 3 and 7 and less on days 14, and more levels of IL-10, IL-4 on days 7 and 14. The levels of TNF-α, IL-6 in the MODS group were different from the non-MODS group, with more levels on days 3 and 7, and less levels on days 14. Immune dysregulation may play an important role in infection and organ dysfunction for patients with SAP.


Assuntos
Citocinas/sangue , Endotoxinas/sangue , Infecções/complicações , Pancreatite/complicações , Pancreatite/imunologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Interleucina-10/sangue , Interleucina-4/sangue , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/mortalidade , Pancreatite/mortalidade , Síndrome de Resposta Inflamatória Sistêmica/imunologia , Resultado do Tratamento , Fator de Necrose Tumoral alfa/sangue
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA