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1.
J Nanosci Nanotechnol ; 18(5): 3433-3440, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442849

RESUMO

The Li1.20[Mn0.54Ni0.13Co0.13]0.80-xYbxO2 (x = 0, 0.01, 0.02, 0.03) cathode materials have been synthesized by using sol-gel method and characterized by means of XRD, SEM, ICP-OES analysis. The galvanostatic charge-discharge tests results showed the improved electrochemical properties were obtained through the Yb3+ doping modification. With the increase of Yb3+ doping content, the capacity retentions enhanced from 85.6% to 88.9% and then decrease to 86.5% after 100 cycles with x = 0.01, 0.02 and 0.03, respectively, while the un-doped sample delivered the capacity retention of 83.0%. Besides, the discharge capacity of Li1.20 [Mn0.54Ni0.13Co0.13]0.78Yb0.02O2 was about 23.1 mAh g-1 larger than that of un-doped sample at 5C high rate. The electrochemical impedance spectroscopy (EIS) and cyclic voltammetric results indicated that the Yb3+ doping modification could suppress the layered-spinel phase transformation during cycling and maintain a lower value of charge transfer impedance.

2.
Inflamm Res ; 64(10): 789-97, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26249853

RESUMO

BACKGROUND AND AIM: Studies have verified the protective effect of Hydrogen Sulfide (H2S) on gastric ulcer and ulcerative colitis, but the mechanisms are not fully illustrated. In this study, the possible protective effect of H2S on TNF-α/IFN-γ induced barrier dysfunction was investigated in Caco-2 cell monolayers. METHOD: The barrier function of Caco-2 monolayers was evaluated by measuring trans-epithelial electrical resistance (TEER) and FITC-Dextran 4 kDa (FD-4) trans-membrane flux. ZO-1 and Occludin were chosen as markers of the localization of tight junction (TJ) proteins for immunofluorescence. The expression of MLCK and phosphorylation level of myosin light chain (MLC) were measured by immunoblotting. The activation of NF-kB p65 was analyzed by EMSA and immunofluorescence. RESULTS: NaHS at 500 uM significantly attenuated TNF-α/IFN-γ-indueced Caco-2 monolayer barrier injury. The increased expression of MLCK and increased phosphorylation level of MLC induced by TNF-α/IFN-γ was also inhibited significantly by NaHS. Additionally, NaHS inhibited TNF-α/IFN-γ induced activation and nuclear translocation of NF-kB p65. CONCLUSION: The present study reveals the protective effect of H2S on TNF-α and IFN-γ-induced injury of intestinal epithelial barrier function in Caco-2 monolayers and suggests that the suppression of MLCK-P-MLC signaling mediated by NF-kB P65 might be one of the mechanisms underlying the protective effect of H2S.


Assuntos
Epitélio/efeitos dos fármacos , Sulfeto de Hidrogênio/farmacologia , Interferon gama/antagonistas & inibidores , Interferon gama/toxicidade , Mucosa Intestinal/efeitos dos fármacos , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/toxicidade , Biomarcadores/metabolismo , Células CACO-2 , Humanos , Mucosa Intestinal/citologia , Cadeias Leves de Miosina/metabolismo , Quinase de Cadeia Leve de Miosina/metabolismo , Ocludina/metabolismo , Fosforilação , Úlcera Gástrica/patologia , Úlcera Gástrica/prevenção & controle , Proteínas de Junções Íntimas/metabolismo , Fator de Transcrição RelA/metabolismo
3.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(4): 1138-41, 2015 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-26197618

RESUMO

For the first time, we real time measured released reaction heat between the binder and the curing agent in the curing process of cast explosive using fiber Bragg grating. In order to obtain the temperature in the process of pouring explosive casting real time and accurately, we designed the temperature monitoring system based on fiber Bragg grating. Given the risk of explosive component, long curing time and the requirements of constant temperature, a suitable measurement method for direct real-time monitoring has not been found. In recent years, due to its superior characteristics, fiber Bragg grating is widely used in the field of communication and sensing. We will make the collected reflection wavelength to convert real-time temperature displaying, utilizing linear relationship between fiber Bragg grating and temperature. Through WDM technology, seven grating points are written in two optical fibers to measure at the same time, and distribution trend of explosives internal temperature can be displayed in real time by multi-point distributed measurement. The curved design of the sensor not only improves the connection between sensor and jumper, but also benefits to place in oven. The txt data is made to draw a graph using origin software, and the changes in temperature in the curing process are displayed intuitively. The results show that this method is simple and high-precision, and meets the testing requirements of curing temperature of explosives.

5.
World J Clin Cases ; 11(8): 1862-1868, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36969994

RESUMO

BACKGROUND: Video-assisted thoracic surgery (VATS) lobectomy is a common treatment for patients with early-stage lung cancer. Some patients can experience slight gastrointestinal discomfort after lobectomy for a moment. Gastroparesis is a gastrointestinal disorder that can be severe; it is associated with an increased risk of aspiration pneumonia and impaired postoperative recovery. Here, we report a rare case of gastroparesis after VATS lobectomy. CASE SUMMARY: A 61-year-old man underwent VATS right lower lobectomy uneventfully but had an obstruction of the upper digestive tract 2 d after surgery. Acute gastroparesis was diagnosed after emergency computed tomography and oral iohexol X-ray imaging. After gastrointestinal decompression and administration of prokinetic drugs, the patient's gastrointestinal symptoms improved. Since perioperative medication was applied according to the recommended dose and there was no evidence of electrolyte imbalance, intraoperative periesophageal vagal nerve injury was the most likely underlying cause of gastroparesis. CONCLUSION: Although gastroparesis is a rare perioperative complication following VATS, clinicians should be on the alert when patients complain about gastrointestinal discomfort. When surgeons resect paraesophageal lymph nodes with electrocautery, excessive ambient heat and compression of paraesophageal hematoma might induce vagal nerve dysfunction.

6.
Curr Oncol ; 30(9): 7874-7890, 2023 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-37754487

RESUMO

Background: Recent studies have found that patients with incurable gastric cancer might benefit from palliative gastrectomy, but the impact of palliative gastrectomy on metastatic early-onset gastric cancer (mEOGC) patients remains unclear. Methods: We analyzed mEOGC patients enrolled in the Surveillance, Epidemiology, and End Results registry from January 2004 to December 2018. Propensity score matching (PSM) analysis with 1:1 matching and the nearest-neighbor matching method were used to ensure well-balanced characteristics between the groups of patients with palliative gastrectomy and those without surgery. Kaplan-Meier survival analysis and Cox proportional hazards regression models were used to evaluate the overall survival (OS) and cause-specific survival (CSS) risk with corresponding 95% confidence intervals (CIs). Results: Of 3641 mEOGC patients, 442 (12.1%) received palliative gastrectomy. After PSM, 596 patients were included in the analysis, with 298 in each group. For the matched cohort, the median survival was 8 months, and the 5-year survival was 4.0%. The median OS of mEOGC patients undergoing palliative gastrectomy was significantly longer than that of patients without surgery (13 months vs. 6 months, p < 0.001), and palliative gastrectomy remained an independent protective factor after adjusting for confounders (HR 0.459, 95% CI 0.382-0.552, p < 0.001), and the protective effect was robust in the subgroup analysis. Similar results were indicated in CSS. Stratified analyses by treatment modality also warranted the superiority of palliative-gastrectomy-based treatment in improving OS and CSS. Conclusions: mEOGC patients with palliative gastrectomy had a significantly longer survival time than patients without surgery. Exploratory analysis confirmed that surgery-based therapy modality was superior in improving survival time.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirurgia , Estudos Retrospectivos , Gastrectomia , Estimativa de Kaplan-Meier , Cuidados Paliativos
7.
J Surg Oncol ; 106(6): 689-95, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22532129

RESUMO

BACKGROUND: Tissue factor (TF) is a significant risk factor for tumor growth and hepatic metastasis in patients with colorectal cancer (CRC). This study aimed to investigate whether hyperthermia has synergistic anti-tumor effects with TF knockdown in suppressing CRC progression and metastasis in vitro and in vivo. METHODS: Human colorectal cancer LOVO cells were treated by hyperthermia at 44°C for 2 hr or/and TF siRNA. Then the cells were subjected to colony formation assay. Apoptosis was analyzed by flow cytometry, confocal microscopy, and transmission electron microscopy. The cell migration and invasion abilities were analyzed by wound healing and matrigel assay. In addition, orthotopic nude mice model of CRC was established. RESULTS: Hyperthermia synergized with TF knockdown to reduce colony formation ability, induce apoptosis, and suppress the migration and invasion of LOVO cells in vitro. Moreover, hyperthermia in combination with TF depletion inhibited the growth and hepatic metastasis of CRC in orthotopic nude mice model. Mechanistically, the synergistic effects were at least partly mediated by inducing JNK mediated apoptosis and suppressing matrix metalloproteinases (MMPs) mediated invasion. CONCLUSIONS: Hyperthermia in combination with TF-targeted therapy could be a potential approach for CRC treatment.


Assuntos
Neoplasias Colorretais/terapia , Hipertermia Induzida , Neoplasias Hepáticas/prevenção & controle , Neoplasias Hepáticas/secundário , Tromboplastina/antagonistas & inibidores , Animais , Apoptose , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Feminino , Proteínas Quinases JNK Ativadas por Mitógeno/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , NF-kappa B/fisiologia , Invasividade Neoplásica , RNA Interferente Pequeno/genética
8.
Int J Colorectal Dis ; 27(4): 437-45, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22076613

RESUMO

PURPOSE: Increased expression of tissue factor (TF) is associated with tumor invasion and metastasis in human colorectal cancer. We have previously observed that TF/FVIIa upregulates matrix metalloproteinase-7 (MMP-7) expression at the transcriptional level in colon cancer cells. MMP-7 overexpression is believed to play an important role in tumor invasion and metastasis. The aim of this study is to elucidate the molecular mechanisms by which TF/FVIIa induced MMP-7 expression and cell invasion in vitro. METHODS: Reverse transcription polymerase chain reaction, Western blot, luciferase assay, and chromatin immunoprecipitation (ChIP) were used to determine the potential mechanism and signaling pathways by which TF/FVIIa induced MMP-7 expression and cell invasion in LoVo cells. Small interfering RNA (siRNA) and cell invasion assay was used to examine whether blocking c-Fos expression could abolish FVIIa-mediated upregulation of MMP-7 and cell invasion in vitro. RESULTS: The results showed that FVIIa induced the upregulation of MMP-7 both at the mRNA and protein levels in a time- and dose-dependent manner and increased the invasive behavior of LoVo cells. FVIIa enhanced the promoter activity of MMP-7, and the activator protein-1 (AP-1) binding site was responsible for the activation. Site mutation of the AP-1 binding site in the promoter almost completely abolished FVIIa-mediated response. Furthermore, ChIP assay confirmed that FVIIa promoted the direct binding of c-Fos with the MMP-7 promoter in vivo. FVIIa also induced the expression and nuclear accumulation of the AP-1 subunit c-Fos. siRNA-mediated knockdown of c-Fos eliminated FVIIa-stimulated MMP-7 expression and cell migration in vitro. In addition, selective mitogen-activated protein kinase (MAPK) kinase (MEK1/2) inhibitor (PD98059) and p38 MAPK inhibitor SB203580 suppressed MMP-7 upregulation induced by FVIIa. CONCLUSIONS: Our data suggest that a novel TF/FVIIa/MAPK/c-Fos/MMP-7 axis plays an important role in modulating the invasion of colon cancer cells and blockage of this pathway holds promise to treat colon cancer metastasis.


Assuntos
Neoplasias do Colo/enzimologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fator VIIa/metabolismo , Metaloproteinase 7 da Matriz/genética , Proteínas Proto-Oncogênicas c-fos/metabolismo , Tromboplastina/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Sítios de Ligação , Linhagem Celular Tumoral , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Ativação Enzimática , Regulação Neoplásica da Expressão Gênica , Humanos , Sistema de Sinalização das MAP Quinases , Metaloproteinase 7 da Matriz/metabolismo , Invasividade Neoplásica , Regiões Promotoras Genéticas/genética , Ligação Proteica , Proteínas Proto-Oncogênicas c-jun/metabolismo , Fatores de Tempo , Fator de Transcrição AP-1/metabolismo , Regulação para Cima/genética
9.
Dig Dis Sci ; 57(12): 3126-35, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22684624

RESUMO

BACKGROUND: Barrier function is essential for the maintenance of normal intestinal function. Dysregulation of the intestinal barrier underlies a wide range of disorders. AIM: Previously, we found that sodium butyrate (NaB) decreased the molecular permeability of intestinal barrier in vivo model, but the mechanism by which NaB facilitated the tightness of tight junctions (TJs) in small intestinal epithelium needed further studies. METHODS: In vitro culture of the cdx2-IEC monolayer was used to mimic barrier function. The TJs were assessed by transepithelial electrical resistance (TEER) and paracellular flux of fluorescein isothiocyanate-conjugated dextran 40,000 (FD-40), Western blot, Q-RT-PCR, and immunofluorescence. Promoter and chromatin immunoprecipitation (ChIP) assays were also done to analyze the Claudin-1 gene. RESULTS: NaB decreased FD-40 flux, increased TEER and TJ protein Claudin-1 expression, induced ZO-1 and Occludin redistribution in cellular membrane, and reversed the damage effect after calcium (Ca(2+)) switch assay. Silencing Claudin-1 prevented protective function of NaB from enhancing intestinal barrier integrity. Further studies demonstrated that NaB increased Claudin-1 transcription by facilitating the interaction between transcription factor SP1 and a specific motif within the promoter region of Claudin-1. This SP1 binding motif was located upstream of the coding region (-138 to -76 bp) and indispensable for the transcription of Claudin-1 following NaB treatment. ChIP assay confirmed the association between SP1 and Claudin-1 promoter, and the elimination of the SP1 binding site by point mutation resulted in a significant loss of Claudin-1 transcription after NaB dealing. CONCLUSIONS: NaB enhanced intestinal barrier function through increasing Claudin-1 transcription via facilitating the association between SP1 and Claudin-1 promoter.


Assuntos
Butiratos/farmacologia , Claudina-1/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/fisiologia , Regulação para Cima/efeitos dos fármacos , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Linhagem Celular , Imunoprecipitação da Cromatina , Claudina-1/genética , Regiões Promotoras Genéticas , Ligação Proteica , Interferência de RNA , Ratos , Fator de Transcrição Sp1/genética , Fator de Transcrição Sp1/metabolismo , Transcrição Gênica
10.
Beijing Da Xue Xue Bao Yi Xue Ban ; 44(6): 937-41, 2012 Dec 18.
Artigo em Zh | MEDLINE | ID: mdl-23247462

RESUMO

OBJECTIVE: To investigate the risk factors for the prognosis in patients with node-negative rectal cancer. METHODS: Clinicopathological characteristics of 117 patients with lymph node-negative rectal carcinoma undergoing curative rectectomy from January 2005 to December 2008 were retrospectively analyzed. RESULTS: The overall 5-year survival rate was 91.5%. The univariate analysis revealed that tumor size(χ(2)=8.422,P=0.004), invasive depth(T staging, χ(2)=9.448,P=0.024), cell differentiation(χ(2)=26.571,P=0.000), pathologic type(χ(2)=4.712,P=0.030) and preoperative level of carcinoembryonic antigen(χ(2)=4.131,P=0.042) had significant effects on the survival. In multivariate analysis, the independent prognostic factors for these patients were tumor size (Wald=5.286,P=0.022), cell differentiation (Wald=7.172, P=0.007) and invasive depth (T staging, Wald=5.741, P=0.017). CONCLUSION: For node-negative rectal cancer patients, tumor size, poor differentiation and invasive depth are important markers to evaluate their prognosis.


Assuntos
Linfonodos/patologia , Neoplasias Retais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Neoplasias Retais/mortalidade , Estudos Retrospectivos , Taxa de Sobrevida
11.
J Gastrointest Surg ; 26(8): 1791-1803, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35501549

RESUMO

BACKGROUND: It is generally accepted that the distal resection margin of intermediate- to low-lying rectal cancer should be greater than 2 cm and at least 1 cm in special cases. This study intends to investigate whether a distal resection margin ≤ 1 cm affects tumor outcomes for patients with intermediate- to low-lying rectal cancer. METHODS: A systematic review of the literature was conducted. Sixteen studies included data for distal resection margins ≤ 1 cm (1684 cases) and > 1 cm (5877 cases), and 5 studies included survival data. Meta-analysis was used to compare the local recurrence rate and long-term survival of patients with distal resection margins > or ≤ 1 cm. RESULTS: The local recurrence rate in the ≤ 1-cm margin group (9.5%) was 2.3% higher than that in the > 1-cm margin group (7.2%) according to a fixed-effects model (RR [95% CI] 1.42 [1.18, 1.70], P < 0.001). The overall survival results of the five 1-cm margin studies showed an HR (95% CI) of 0.96 (0.75, 1.24) (P = 0.78). Subgroup analysis showed that the local recurrence rate in the subgroup with perioperative treatment was 1.2% lower in the ≤ 1-cm margin group (8.3%) than in the > 1-cm margin group (9.5%) (RR [95% CI] 0.97 [0.63, 1.49], P = 0.90). In the surgery alone subgroup, the local recurrence rate was 4.7% higher in the ≤ 1-cm margin group (12.4%) than in the > 1-cm group (7.7%) (RR [95% CI] 1.76 [1.09, 2.83], P = 0.02). CONCLUSIONS: For patients with intermediate- to low-lying rectal cancer undergoing surgery alone, a distal resection margin ≤ 1 cm may be not safe.


Assuntos
Margens de Excisão , Neoplasias Retais , Humanos , Recidiva Local de Neoplasia/patologia , Neoplasias Retais/patologia , Resultado do Tratamento
12.
J Gastrointest Oncol ; 13(5): 2293-2305, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36388673

RESUMO

Background: Patients with stage IIA rectal cancer have a higher survival rate but side effects from chemoradiotherapy; thus, whether neoadjuvant therapy should be performed for stage IIA rectal cancer is controversial. This study aimed to compare the survival outcomes of patients with stage IIA rectal cancer with or without neoadjuvant chemoradiotherapy. Methods: Patients with stage IIA rectal cancer between 2010 and 2015 were included through the Surveillance, Epidemiology, and End Results database. Propensity score matching was used to reduce the impact of confounding factors. Survival curves were plotted using the Kaplan-Meier method, and survival differences were assessed using the log-rank test. Results: There were no significant differences in overall survival and cancer-specific survival between the neoadjuvant chemoradiotherapy and surgery groups (P=0.973 and 0.983). Compared with the surgery group, the neoadjuvant chemoradiotherapy + surgery + chemotherapy group had a better overall survival (P=0.007). Subgroup analysis showed that the neoadjuvant chemoradiotherapy + surgery + chemotherapy group had better overall survival compared to the surgery group in the subgroup containing preoperative high-risk factors (P=0.003) but not in the low-risk subgroup (P=0.685). Conclusions: There is no evidence that neoadjuvant chemoradiotherapy + surgery can improve overall survival and cancer-specific survival compared to surgery alone in patients with stage IIA rectal cancer. Neoadjuvant chemoradiotherapy + surgery + chemotherapy can improve overall survival compared to surgery alone, but only in patients with preoperative high-risk factors. We suggest that patients with no preoperative high-risk factors may be considered for surgery alone, neoadjuvant chemoradiotherapy + surgery + chemotherapy is recommended for patients with preoperative risk factors.

13.
World J Clin Cases ; 10(10): 3241-3250, 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35647117

RESUMO

BACKGROUND: Appendico-vesicocolonic fistulas and appendiceal-colonic fistulas are two kinds of intestinal and bladder diseases that are rarely seen in the clinic. To our knowledge, no more than 4 cases of appendico-vesicocolonic fistulas have been publicly reported throughout the world, and no more than 100 cases of appendiceal-colonic fistulas have been reported. Although the overall incidence is low, an early diagnosis is difficult due to their atypical initial symptoms, but these diseases still require our attention. CASE SUMMARY: Here, we report a case of a 77-year-old male patient diagnosed with an appendico-vesicocolonic fistula combined with an appendiceal-colonic fistula. The main manifestations were diarrhea and urine that contained fecal material. The diagnosis was confirmed by multiple laboratory and imaging examinations. A routine urinalysis showed red blood cells and white blood cells. Abdominal and pelvic computed tomography scans showed close adhesions between the bowels and the bladder, and fistulas could be seen. Colonoscopy and cystoscopy and some other imaging examinations clearly showed fistulas. The preoperative diagnoses were a colovesical fistula and an appendiceal-colonic fistula. The fistulas were repaired by laparoscopic surgical treatment. The diseased bowel and part of the bladder wall were removed, followed by a protective ileostomy. The postoperative diagnosis was an appendico-vesicocolonic fistula combined with an appendiceal-colonic fistula, and the pathology suggested inflammatory changes. The patient recovered well after surgery, and all his symptoms resolved. CONCLUSION: The final diagnosis in this case was a double fistula consisting of an appendico-vesicocolonic fistula combined with an appendiceal-colonic fistula.

14.
Beijing Da Xue Xue Bao Yi Xue Ban ; 43(2): 204-8, 2011 Apr 18.
Artigo em Zh | MEDLINE | ID: mdl-21503113

RESUMO

OBJECTIVE: To study the influence of proline-rich tyrosine kinase 2 (Pyk2) on hepatic metastasis and microstructure of colon cancer cells in nude mice. METHODS: Hepatic metastases of colonic cancer were established in Babl/c nu/nu nude mice by splenic injection of colonic cancer cells SW480 which were transfected with sense-Pyk2 plasmid and antisense-Pyk2 plasmid. After six weeks, we counted the number of liver metastases in each group and observed the ultrastructure of tumor cells in each group by electron microscopy; furthermore, we tried to find out the correlationship between Pyk2 expression and the number of colonic cancer liver metastases. RESULTS: Difference was found between the nude mice injected with sense-Pyk2 plasmid and antisense-Pyk2 plasmid, and there was correlation between Pyk2 expression and the number of liver metastases, Pyk2 could inhabit the liver metastasis of colonic adenocarcinoma. In contrast, the ultrastructure of tumor cell had less heteromorphism in nude mice transfected with sense-Pyk2 plamisd. CONCLUSION: Pyk2 can reduce the number of liver metastasis of colonic adenocarcinoma, and also the heteromorphism of tumor cells which inhabit the progress of colonic adenocarcinoma liver metastasis.


Assuntos
Neoplasias do Colo/patologia , Quinase 2 de Adesão Focal/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundário , Animais , Quinase 2 de Adesão Focal/genética , Humanos , Neoplasias Hepáticas/ultraestrutura , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica/prevenção & controle , Plasmídeos , Transfecção
15.
Materials (Basel) ; 14(15)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34361377

RESUMO

In this paper, the thermal decomposition behavior of 3,5-difluoro-2,4,6-trinitroanisole (DFTNAN) was studied by differential scanning calorimetry (DSC) and thermogravimetry (TG) by using different heating rates (2, 5, 10, 15 °C·min-1). Subsequently, the kinetic and thermodynamic parameters of non-isothermal thermal decomposition of DFTNAN were calculated. The critical temperature of thermal explosion (Tb) and self-accelerating decomposition temperature (TASDT) were determined to be 249.03 °C and 226.33 °C, respectively. The compatibility of DFTNAN with a number of high explosives (cyclo-1,3,5-trimethylene-2,4,6-trinitramine (RDX), 1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaaza-tetracyclo-[5.5.0.05,9.03,11]-dodecane (CL-20) and dihydroxylammonium 5,5'-bistetrazole-1,1'-diolate (TKX-50)) was studied at different mass ratios using DSC. The criteria to judge the compatibility between the materials were based on a standardization agreement (STANAG 4147). The thermodynamic study results revealed that DFTNAN possessed superior thermal safety and stability. The experimental of compatibility results indicated that the mass ratios of the high explosives in the DFTNAN/RDX, DFTNAN/HMX and DFTNAN/CL-20 compositions more than 40%, 60% and 70% exhibited good compatibility, whereas DFTNAN/TKX-50 demonstrated poor compatibility.

16.
Huan Jing Ke Xue ; 41(9): 3932-3940, 2020 Sep 08.
Artigo em Zh | MEDLINE | ID: mdl-33124272

RESUMO

In a recent field campaign focused on air quality study, aerosol optical properties, particle number concentration, and PM2.5 components were monitored in Changzhou, Jiangsu Province, from May 27 to June 27, 2019. An array of instruments were deployed that included scanning mobility particle size spectrometer (SMPS), aethalometer (AE33), cavity attenuation phase shift single albedo monitor (CAPS-ALB), monitor for aerosols and gases in ambient air (MARGA) and RT-4 organic carbon/elemental carbon (OC/EC) carbon analyzer to study the ① changes in chemical composition and optical parameters of the new particles generated during the campaign period. ② comparison of the aerosol extinction coefficient recorded by these instruments and measured value in the reconstruction of IMPROVE (interagency monitoring of protected visual environment) and the calculated coefficient using MIE theory model were carried out. During the entire campaign, two new particle generation events were observed and also found that the particle size continued to increase from 4 nm to 64 nm. It was monitored that in the initial stage of new particle generation, sulfate contributed greatly. The measured average aerosol extinction coefficient during the period of particle generation, using these instruments was 95.40 Mm-1, while the average aerosol extinction reconstruction using the IMPROVE model was observed to be 140.20 Mm-1. The theoretical calculations based on Mie theory model yielded an average extinction coefficient of 93.54 Mm-1. It was found that the average aerosol extinction in Changzhou is lower than the average value of the urban aerosol extinction coefficient, which is measured to be 300 Mm-1 in China, during this period. The deployment of multiple instruments in a single campaign is more desirable because the combination of all observations helped in better characterization of the physicochemical properties of ambient aerosols from various aspects, including particle size spectrum and chemical composition.

17.
Beijing Da Xue Xue Bao Yi Xue Ban ; 41(5): 531-6, 2009 Oct 18.
Artigo em Zh | MEDLINE | ID: mdl-19829668

RESUMO

OBJECTIVE: To study the expression of coagulation factor VII(FVII)/tissue factor(TF)complex in colorectal carcinoma (CRC)and its correlation with clinicopathologic factor. METHODS: The expression of coagulation factor VII protein was studied by immunohistochemistry and Western blot.The expression of tissue factor and coagulation factor VII at the mRNA levels were evaluated by quantitative realtime RT-PCR in 45 cases of CRC. RESULTS: (1) FVII overexpression was ectopicly detected in CRC specimens at protein level by immunohistochemistry and Western blot, but not in adjacent non-cancerous mucosa of colorectum;(2)FVII protein mainly localized in the cytoplasm of colon cancer cells.The positive ratios of FVII protein expression in stages I, II, III and IV by immunohistochemistry assay were 33.3%, 40.0%, 64.7% and 80.0% respectively(P=0.001); (3)The expression of FVII mRNA in CRC with hepatic metastasis was significantly higher than that in CRC without hepatic metastasis.The relative expression was 5.33+/-2.88 and 1.47+/-0.51 respectively(P=0.03). Overexpression FVII gene was unrelated with tumor size, differentiation, depth of invasion, lymph node metastasis and TNM staging.There existed some relation between the gene and protein level by Spearman correlation, r=0.58, P=0.003;(4)The expression of TF mRNA in CRC significantly correlated with lymph node metastasis, hepatic metastasis and TNM staging.The expression of tissue factor was a critical factor to predict liver metastasis by logistic regression analysis(P=0.001). CONCLUSION: Colorectal cancer can ectopicly synthesize coagulation factor VII.Tissue factor expression may play a role in the process of developing hepatic metastasis.The microenvironment of high dose FVII protein may promote tumor metastasis.


Assuntos
Neoplasias Colorretais/metabolismo , Fator VII/metabolismo , Neoplasias Hepáticas/secundário , Tromboplastina/metabolismo , Adulto , Idoso , Neoplasias Colorretais/patologia , Fator VII/genética , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/metabolismo , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tromboplastina/genética
18.
Zhonghua Wai Ke Za Zhi ; 47(13): 984-7, 2009 Jul 01.
Artigo em Zh | MEDLINE | ID: mdl-19957807

RESUMO

OBJECTIVE: To evaluate the prognostic value of lateral pelvic lymph node metastasis on low rectal cancer. METHODS: One hundred and seventy-six patients with low rectal cancer who underwent radical resection combined with lateral pelvic lymph node dissection between 1994 and 2005 were reviewed. The data of the cases was investigated to define the prognostic value of lateral pelvic lymph node metastasis on the patients. RESULTS: Lateral node metastasis occurred in 33 patients (18.8%), and 51.5% of the metastasis occurred in internal iliac nodes or nodes at middle rectal roots and 39.4% in obturator nodes. Age < or =40 years, infiltrative cancer, T34 tumor, upward lymph node metastasis were risk factors for lateral node metastasis in low rectal cancer (P < 0.05). The overall 5-year survival rate was 64.1%, and it was 94.1%, 79.1%, 42.1% for patients with TNM stage I, II, III cancer, respectively. Tumor size, depth of infiltration, upward lymph node metastasis, lateral node metastasis was correlated significantly with prognosis (P < 0.05). The 5-year survival rate of the patients without lateral metastasis was 73.6%, which was significant higher than that of patients with lateral metastasis (21.4%, P < 0.05). CONCLUSION: Lateral pelvic lymph node metastasis is an important prognostic factor for low rectal cancer.


Assuntos
Linfonodos/patologia , Metástase Linfática/patologia , Neoplasias Retais/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Modelos Logísticos , Excisão de Linfonodo , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Pelve/patologia , Prognóstico , Neoplasias Retais/patologia , Estudos Retrospectivos , Adulto Jovem
19.
Huan Jing Ke Xue ; 40(6): 2510-2518, 2019 Jun 08.
Artigo em Zh | MEDLINE | ID: mdl-31854640

RESUMO

Secondary species are one of the most important components of PM1 particles. To investigate the contributions as well as the factors that affect the formation of the secondary aerosols, a high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS, AMS) was employed to characterize sub-micron particles (PM1) during spring and summer in urban Shanghai. Organics were dominant in PM1 particles and comprised around 55% of the total PM1 mass concentration, followed by sulfate (24%) and nitrate (10%). Positive matrix factorization was further applied to explore the sources of the organics. It was found that primary and secondary organic aerosols accounted for around 34% and 66% of the total organics, respectively. Three episodes were observed during the measurements, where secondary species increased substantially. Increases of secondary species were represented by increases of sulfate and LV-OOA1 in spring, especially during the noontime, thus indicating that their formation is promoted by photochemical oxidation; yet in summer, photochemical and aqueous chemistry together accelerate the formation of secondary species, as indicated by the good correlations between nitrate and aerosol liquid water as well as between SOA and Ox. Overall, we found that contributions from secondary organic and inorganic aerosols to total PM1 particles were 35.5% and 43%, respectively. This study highlights that the influence of photochemical and aqueous chemistry is significant in the promotion of secondary species formation in Shanghai.

20.
Zhonghua Yi Xue Za Zhi ; 88(47): 3319-24, 2008 Dec 23.
Artigo em Zh | MEDLINE | ID: mdl-19257960

RESUMO

OBJECTIVE: To investigate the genetic differences and their relativity with multi-drug resistance of Pseudomonas aeruginosa isolated. METHODS: Forty-nine Pseudomonas aeruginosa isolates were characterized by antimicrobial susceptibility and four-enzyme (I-CeuI, SpeI, SwaI, PacI) pulsed-field gel electrophoresis (PFGE). RESULTS: 85.7% of the P.aeruginosa isolates were MDR strains. Strains with PFGE pattern A were all susceptible to amikacin and cefepime, but were resistant to levofloxacin and meropenem. Strains with PFGE Patterns H and P had resistance to 6 - 8 different kinds of antibiotics. Strains with PFGE Patterns I and J were susceptible to all antibiotics tested in this study. Strains with other PFGE Patterns had intermediate resistance. PFGE pattern A was the dominant pattern, which accounted for 61.2% of all P.aeruginosa strains, 100% (2/2) in 2001, 65% (13/20) in 2002, 44.4% (8/18) in 2003 and 77.8% (7/9) in 2004. CONCLUSION: Four-enzyme combined PFGE analysis is highly discriminatory for the subtyping of MDR P.aeruginosa isolates.


Assuntos
Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genética , Genoma Bacteriano , Pseudomonas aeruginosa/genética , Técnicas de Tipagem Bacteriana , Eletroforese em Gel de Campo Pulsado , Humanos , Unidades de Terapia Intensiva , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/isolamento & purificação
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