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1.
Artigo em Inglês | MEDLINE | ID: mdl-34792614

RESUMO

PURPOSE: The optimal surgical procedure, whether total gastrectomy (TG) or proximal gastrectomy (PG), for Siewert type II/III adenocarcinoma of esophagogastric junction (AEG) has not been standardised, primarily because the optimal extent of lymph node (LN) dissection for AEG based on the metastatic rate of perigastric LNs remains under debate. The aim of this study was to investigate the metastatic incidence and prognostic significance of lower perigastric lymph nodes (LPLN), including No.4d, 5, 6 and 12a LN stations, in Siewert type II/III AEG. METHODS: A total of 701 patients with Siewert type II/III AEG who received transabdominal open gastrectomy (425 patients with TG and 276 patients with PG) from 2010 to 2015 in West China Hospital were retrospectively included. Based on the clinicopathological information of TG patients, the risk factors of LPLN-positive patients were evaluated, and the metastatic incidence as well as the therapeutic value (TV) index of each LN station was assessed. Moreover, the 5-year overall survival (OS) rates between LPLN-positive and LPLN-negative groups were compared in TG patients, and the postoperative survival difference between TG and PG patients was also compared, using propensity score matching (PSM) method. RESULTS: Tumour size (≥ 5 cm, OR = 1.481, p = 0.002) and pT stage (pT4, OR = 2.755, p = 0.024) were significant risk factors for patients with LPLN metastasis. For patients with tumour size more than 5 cm or pT4 stage, the metastatic rates of LPLN for Siewert type II, III and II/III AEG were 31.67%, 34.69% and 33.03%, whereas the TV indexes of LPLN for them were 5.76, 5.62 and 5.38, respectively. LPLN was a significant independent prognostic factor (HR = 1.422, p = 0.028), and positive LPLN was related to worse prognosis (p < 0.05). For patients with tumour size more than 5 cm or pT4 stage, TG patients were illustrated to have a better prognosis than PG patients, with 5-year OS rates of 58.9% vs 38.2% for Siewert type II AEG (χ2 = 4.159, p = 0.041), 68.9% vs 50.2% for Siewert type III AEG (χ2 = 5.630, p = 0.018) and 65.1% vs 40.3% for Siewert type II/III AEG (χ2 = 12.604, p < 0.001), respectively. CONCLUSIONS: LPLN metastasis is a poor prognostic factor for patients with Siewert II/III AEG. LPLN dissection may improve the long-term survival of patients with tumour size more than 5 cm or pT4 stage, and TG might be more suitable for this kind of cancer.

2.
Emerg Microbes Infect ; 10(1): 37-50, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33296295

RESUMO

Hepatitis B e antigen (HBeAg) is a widely used marker both for chronic hepatitis B (CHB) clinical management and HBV-related basic research. However, due to its high amino acid sequence homology to hepatitis B core antigen (HBcAg), most of available anti-HBe antibodies are cross-reactive with HBcAg resulting in high interference against accurate measurement of the status and level of HBeAg. In the study, we generated several monoclonal antibodies (mAbs) targeting various epitopes on HBeAg and HBcAg. Among these mAbs, a novel mAb 16D9, which recognizes the SKLCLG (aa -10 to -5) motif on the N-terminal residues of HBeAg that is absent on HBcAg, exhibited excellent detection sensitivity and specificity in pairing with another 14A7 mAb targeting the HBeAg C-terminus (STLPETTVVRRRGR, aa141 to 154). Based on these two mAbs, we developed a novel chemiluminescent HBeAg immunoassay (NTR-HBeAg) which could detect HBeAg derived from various HBV genotypes. In contrast to widely used commercial assays, the NTR-HBeAg completely eliminated the cross-reactivity with secreted HBcAg from precore mutant (G1896A) virus in either cell culture or patient sera. The improved specificity of the NTR-HBeAg assay enables its applicability in cccDNA-targeting drug screening in cell culture systems and also provides an accurate tool for clinical HBeAg detection.


Assuntos
Anticorpos Anti-Hepatite B/análise , Antígenos E da Hepatite B/química , Vírus da Hepatite B/genética , Hepatite B Crônica/imunologia , Motivos de Aminoácidos , Anticorpos Monoclonais/análise , Técnicas de Cultura de Células , Linhagem Celular , Epitopos/imunologia , Genótipo , Células Hep G2 , Antígenos do Núcleo do Vírus da Hepatite B/química , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Antígenos E da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Hepatite B Crônica/sangue , Humanos , Medições Luminescentes
3.
J Zhejiang Univ Sci B ; 21(9): 749-751, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32893532

RESUMO

Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was found initially in Wuhan, China in early December 2019. The pandemic has spread to 216 countries and regions, infecting more than 23310 000 people and causing over 800 000 deaths globally by Aug. 24, 2020, according to World Health Organization (https://www.who.int/emergencies/diseases/ novel-coronavirus-2019). Fever, cough, and dyspnea are the three common symptoms of the condition, whereas the conventional transmission route for SARS-CoV-2 is through droplets entering the respiratory tract. To date, infection control measures for COVID-19 have been focusing on the involvement of the respiratory system. However, ignoring potential faecal transmission and the gastrointestinal involvement of SARS-CoV-2 may result in mistakes in attempts to control the pandemic.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Fezes/virologia , Gastroenteropatias/virologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Betacoronavirus/genética , COVID-19 , China/epidemiologia , Infecções por Coronavirus/epidemiologia , Microbiologia Ambiental , Humanos , Modelos Biológicos , Pandemias , Pneumonia Viral/epidemiologia , RNA Viral/análise , RNA Viral/genética , SARS-CoV-2 , Eliminação de Partículas Virais
4.
Nanoscale Res Lett ; 14(1): 89, 2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30868364

RESUMO

Highly branched metallic nanostructures, which possess a large amount of catalyst active sites and surface-enhanced Raman scattering (SERS) hot spots owing to their large surface areas, multi-level branches, corners, and edges, have shown potential in various applications including catalysis and SERS. In this study, well-defined dendritic silver (Ag) nanostructures were prepared by a facile and controllable electrochemical deposition strategy. The morphology of Ag nanostructures is controlled by regulating electrodeposition time and concentration of AgNO3 in the electrolyte solution. Compared to conventional Ag nanoparticle films, dendritic Ag nanostructures exhibited larger SERS enhancement ascribed to the numerous hot spots exist in the nanogaps of parallel and vertically stacked multilayer Ag dendrites. In addition, the prepared dendritic Ag nanostructures show 3.2-fold higher catalytic activity towards the reduction of 4-nitrophenol (4-NP) by NaBH4 than the Ag nanoparticle films. The results indicate that the dendritic Ag nanostructures represent a unique bifunctional nanostructure that serves as both efficient catalysts and excellent SERS substrates, which may be further employed as a nanoreactor for in situ investigation and real-time monitoring of catalytic reactions by SERS technique.

5.
Micromachines (Basel) ; 10(3)2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30875813

RESUMO

We study the effect of etching depth on the threshold characteristics of GaSb-based middle infrared (Mid-IR) photonic-crystal surface-emitting lasers (PCSELs) with different lattice periods. The below-threshold emission spectra are measured to identify the bandgap as well as band-edge modes. Moreover, the bandgap separation widens with increasing etching depth as a result of enhanced diffraction feedback coupling. However, the coupling is nearly independent of lattice period. The relationship between threshold gain and Bragg detuning is also experimentally determined for PCSELs and is similar to that calculated theoretically for one-dimensional distributed feedback lasers.

6.
Materials (Basel) ; 12(2)2019 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-30669560

RESUMO

This paper discusses the issue of controlling the epitaxial growth of mixed group V alloys to form a type-I InGaAsSb/AlGaAsSb double quantum wells (QWs) structure. We also discuss the run-to-run reproducibility of lattice-matched AlGaAsSb alloys and strained In0.35Ga0.65As0.095Sb0.905 in terms of growth parameters (V/III ratio, Sb2/As2 ratio). Molecular beam epitaxy (MBE) was used to grow two type-I InGaAsSb double-QWs laser structures differing only in the composition of the bottom cladding layer: Al0.85Ga0.15As0.072Sb0.928 (sample A) and Al0.5Ga0.5As0.043Sb0.957 (sample B). Both samples were respectively used in the fabrication of photonic crystal surface-emitting lasers (PCSELs). Sample A presented surface lasing action from circular as well as triangular photonic crystals. Sample B did not present surface lasing due to the deterioration of the active region during the growth of the upper cladding. Our findings underline the importance of temperature in the epitaxial formation of AlxGa1-xAsySb1-y in terms of lasing performance.

7.
Biosci Rep ; 39(8)2019 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-29700213

RESUMO

Increasing evidence suggests that microRNAs (miRNAs) play a critical role in tumorigenesis. Decreased expression of miR-382 has been observed in various types of cancers. However, the biological function of miR-382 in colorectal cancer (CRC) is still largely unknown. Here, we found that miR-382 was down-regulated in human colorectal cancer tissues and cell lines associated with it. MiR-382 inhibited colorectal cancer cell proliferation, migration, invasion, and enhance chemosensitivity. Furthermore, we identified Krüppel-like factor 12 (KLF12) and homeodomain-interacting protein kinase 3 (HIPK3) as the target of miR-382, and miR-382 rescued the promotion effect of KFL12 on migration and enhanced chemosensitivity in colorectal cancer cell lines. Collectively, these findings revealed that miR-382 inhibits migration and enhances chemosensitivity by targeting KLF12 and HIPK3 in colorectal cancer. These findings might serve as a tumor suppressor in CRC.


Assuntos
Neoplasias Colorretais/genética , Genes Supressores de Tumor/fisiologia , MicroRNAs/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica/genética , Células HCT116 , Humanos , Fatores de Transcrição Kruppel-Like/genética
8.
Opt Express ; 26(10): 13483-13488, 2018 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-29801373

RESUMO

We investigate threshold current temperature dependence of electrically injected quantum-dot (QD) photonic crystal (PC) surface-emitting lasers (SELs) with respect to wavelength detuning between QD gain peak and PC cavity resonance. The lasing emissions cover wavelengths from 1283 nm to 1318 nm. Almost infinite characteristic temperature is realized at certain temperature range for PCSEL with large negative gain-cavity detuning. Moreover, band-edge lasing mode is identified in our "PC slab-on-substrate" structure, and its far-field distribution is characterized as doughnut-shaped beam with azimuthal polarization.

9.
J Zhejiang Univ Sci B ; 16(11): 897-903, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26537207

RESUMO

OBJECTIVE: To explore the feasibility and clinical value of secondary sentinel lymph node (SSLN) tracing technique in radical gastrectomy for advanced gastric cancer (AGC). METHODS: From January 2009 to June 2011, 247 patients who suffered from gastric angle cancer with metastasis in No. 3 group lymph nodes were divided randomly into groups A and B. Methylthioninium chloride was injected into the peripheral tissue of the metastatic No. 3 group lymph nodes of 138 patients in group A before tumor resections. SSLNs were traced and individual lymphadenectomies were carried out based on the biopsy results of the SSLNs. Standard D2 radical gastrectomies were carried out directly on 109 patients in group B. Postoperative follow-up and survival analysis were carried out for patients in both groups. RESULTS: SSLNs were found in 114 (82.6%) patients in group A. Ninety of those patients (78.9%) demonstrated existing metastasis in SSLNs. According to Kaplan-Meier's method, the postoperative 3-year cumulative survival rates were 63.5% and 47.5%, and the median survival time were 40 and 36 months for the patients of groups A and B, respectively (P<0.05). CONCLUSIONS: The SSLN tracing technique is feasible in radical gastrectomy for AGC. It gives surgeons important information about the terminal status of lymph node metastasis and provides some scientific basis for individual lymphadenectomy.


Assuntos
Gastrectomia , Excisão de Linfonodo , Linfonodos/patologia , Neoplasias Gástricas/patologia , Adulto , Idoso , Feminino , Humanos , Excisão de Linfonodo/métodos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Biópsia de Linfonodo Sentinela , Neoplasias Gástricas/cirurgia
10.
Appl Opt ; 52(28): 6906-9, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24085204

RESUMO

We have proposed and fabricated a new mid-infrared reflector using the guided-mode resonance (GMR). The GMR reflector consists of subwavelength Ge grating on GaAs substrate with a low-refractive-index SiOx layer in between. With a total thickness of about 2 µm, a near-100% reflectivity at 8 µm has been obtained both theoretically and experimentally.

11.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 39(2): 142-5, 2004 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-15061891

RESUMO

OBJECTIVE: To study dynamic relation between periodontal pathogens and cariogenic bacteria under analogous oral environment. METHODS: Eight periodontopathic and cariogenic bacteria of Porphyromonas gingivalis (Pg), Actinobacillus actinomycetemcomitans (Aa), Fusobacterium nucleatum (Fn), Provotella intermedium (Pi), Streptococcus mutans (Sm), Streptococcus sanguis (Ss), Actinomyces viscosus (Av) and Lactobacillus acidophilus (La) were used. These eight strains were cultured in modified chemostat under analogous oral environment which contained 600 ml modified BM medium supplemented with 2.5 g/L porcine gastric mucin, respectively. After 1, 24, 48 and 96 h, optical sectioning of plaque biofilms on removable and replaceable hydroxyapatite disks was analyzed by the combination of live bacterial Gram fluorescence staining and confocal laser scanning microscopy. Biofilm thickness and reconstruction of the three-dimensional architecture of plaque biofilms were made. RESULTS: Biofilm thickness increased significantly with time (P < 0.001). Biofilms of Aa were thinner than those of Ss and eight-specie biofilms were thicker than those formed by Ss and Aa per time point. Three-dimensional images showed periodontal pathogens mainly occurred in cariogenic bacterial complex or on the biofilm surface. CONCLUSIONS: Gram-positive cariogenic species initially predominated in artificial plaque, followed by the increasing proportions of Gram-negative periodontal pathogens. The relation between microecological balance among bacteria and diseases is worthy of further studies.


Assuntos
Bactérias/crescimento & desenvolvimento , Biofilmes , Cárie Dentária/microbiologia , Doenças Periodontais/microbiologia , Ecologia , Humanos , Microscopia Confocal
12.
Zhonghua Nan Ke Xue ; 8(2): 92-4, 2002.
Artigo em Chinês | MEDLINE | ID: mdl-12479017

RESUMO

OBJECTIVES: To study the inhibitory effect of KF-950 on human acrosin and sperm acrosome. METHODS: Human acrosin was extracted and purified with 2% acetic acid, and its residual activity was evaluated by BAEE/ADH assay after treated with different concentrations of KF-950. ABC assay was used to observe the effect of KF-950 on human acrosome with Biotin-PSA as a probe. RESULTS: 1. The activity of normal sperm acrosin was (37.65 +/- 4.47) U/L. 2. The residual activity was inversely related to the concentration of KF-950 (r = -0.998), and had a dose-response curve. The result could be described by Y = 7.57-1.895X. 3. With increase of KF-950 concentration and prolongation of action time, the staining rate of acrosome obviously dropped (P < 0.01). CONCLUSIONS: KF-950 directly inhibits acrosin activity and assumely injures sperm acrosome. It might be a new kind of highly effective inhibitor.


Assuntos
Acrosina/antagonistas & inibidores , Acrossomo/metabolismo , Espermatozoides/efeitos dos fármacos , Humanos , Masculino , Espermatozoides/fisiologia
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