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1.
Opt Lett ; 48(16): 4257-4260, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37582006

RESUMO

This Letter presents a dispersion spectroscopy method that achieves simultaneous detection of molecular vibrational dispersion over a broad spectral range. The method is implemented with an infrared mode-locked laser, a dispersion-compensated Michelson interferometer, and a multichannel detector. Synchronous detection under interferometric phase modulation near the destructive interference condition is employed to achieve a high signal-to-noise ratio. We successfully demonstrate the method by measuring the dispersion of carbon monoxide gas, achieving a noise-equivalent dispersion of 1.3 × 10-8 cm and a corresponding noise-equivalent absorbance of 6.5 × 10-4 with a measurement time of 2.2 s.

2.
Opt Express ; 30(21): 38674-38683, 2022 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-36258426

RESUMO

We demonstrate high-sensitivity vibrational absorption spectroscopy in the 2-micron wavelength range by using a mode-locked Cr:ZnS laser. Interferometric subtraction and multichannel detection across the broad laser spectrum realize simultaneous background-free detection of multiple vibrational modes over a spectral span of >380 cm-1. Importantly, we achieve detection of small absorbance on the order of 10-4, which is well below the detection limit of conventional absorption spectroscopy set by the detector dynamic range. The results indicate the promising potential of the background-free method for ultrasensitive and rapid detection of trace gases and chemicals.

3.
Opt Lett ; 47(23): 6077-6080, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37219176

RESUMO

We demonstrate spectral peak formation in a mode-locked solid-state laser that contains a gas cell inside the cavity. Symmetric spectral peaks appear in the course of sequential spectral shaping through resonant interaction with molecular rovibrational transitions and nonlinear phase modulation in the gain medium. The spectral peak formation is explained as that narrowband molecular emissions triggered by an impulsive rovibrational excitation are superposed on the broadband spectrum of the soliton pulse by constructive interference. The demonstrated laser, which exhibits comb-like spectral peaks at molecular resonances, potentially provides novel tools for ultrasensitive molecular detection, vibration-mediated chemical reaction control, and infrared frequency standards.

4.
Opt Lett ; 47(3): 637-640, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35103692

RESUMO

Self-powered ultraviolet detectors may find application in aviation and military fields. Here we demonstrate a self-powered asymmetric metal-semiconductor-metal (MSM) deep ultraviolet (DUV) detector with an Ni/Al electrode contact to AlN, and a photoelectric response current increase from dark current (Id) 2.6 × 10-12 A to 1.0 × 10-10 A after UV illumination (Ip) at 0 V bias. To further improve device performance, trenches are etched in AlN, and the Ni/Al electrodes are deposited in trenches to form a three-dimensional MSM (3D-MSM) structure. The improved performance is attributed to the stronger electric field from the asymmetric electrode and a shorter carrier migration path from the 3D-MSM device configuration. Our work will promote the development and application of DUV self-powered devices.

5.
Opt Lett ; 45(24): 6711-6714, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33325876

RESUMO

III-nitride-based distributed Bragg reflectors (DBRs) are advantageous in being in-situ integrated in III-nitride devices, and the bandgaps and their other corresponding optical parameters are tunable. However, a growing nitride DBR with low strain and high reflectivity remains a challenge. Here we demonstrate an AlN/InxAl1-xN DBR grown on Si and SiO2 substrates by reactive radio-frequency magnetron sputtering. Reflectance wavelengths covering the whole visible regions of the visible spectrum were achieved by rationally tuning the indium composition in InxAl1-xN and each layer's thickness of an AlN/InxAl1-xN DBR. This Letter should advance the design and fabrication of nitride optical and optoelectrical devices by incorporating an AlN/InxAl1-xN DBR, such as vertical-cavity surface-emitting laser (VCSEL) and RC LEDs.

6.
Nanotechnology ; 31(14): 145713, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-31860878

RESUMO

Seed-catalysed growth has been proved to be an ideal method to selectively tune the crystal structure of III-V nanowires along its growth axis. However, few results on relevant nitride NWs have been reported. In this study, we demonstrate the growth of epitaxial kinked wurtzite (WZ)/zinc-blende (ZB) heterostructure GaN NW arrays under the oxygen rich condition using hydride vapour-liquid-solid vapour phase epitaxy (VLS-HVPE). The typical GaN crystal includes WZ and ZB phases throughout the whole NW structure. A detailed structural analysis indicates that a stacking faults free zone was occasionally observed near the NW tips and in the relatively long kinked 〈11-23〉 directions segments (>200 nm). Furthermore, some NWs (<5%) develop phase boundaries, resulting in kinking and crystal phase evolution. A layer-by-layer growth mode was proposed to explain the crystal phase evolution along the phase boundaries. This study provides new insights into the controlled growth of wurtzite (WZ)/zinc-blende (ZB) heterostructure GaN NW.

7.
J Cell Biochem ; 120(8): 14095-14106, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31087707

RESUMO

AIMS: This study was conducted to explore the function of microRNA-141-3p/cyclin-dependent kinase 8 (miR-141-3p/CDK8) in regulating trastuzumab resistance of breast cancer cells. MATERIALS AND METHODS: Microarray analysis was performed to screen microRNAs that are differentially expressed in wild type and trastuzumab-resistant (TR) breast cancer cell lines. TargetScan helped predict the target gene of miR-141-3p. The regulatory relationship was confirmed through a luciferase reporter assay, quantitative reverse transcriptase polymerase chain reaction, and Western blot analysis. The MTT assay, transwell invasion assay, and wound scratch assay were performed to measure the proliferative, invasive, and migratory ability of breast cancer cells, respectively. Tumor cell xenografts in nude mice were conducted to observe the effect of miR-141-3p on trastuzumab resistance in breast cancer cells in vivo. The enzyme-linked immunosorbent assay was used to detect protein secretion. RESULTS: miR-141-3p was downregulated in the drug-resistant cell lines. CDK8 was proved to be a target gene of miR-141-3p. Transfection of miR-141-3p or CDK8 small interfering RNA (siRNA) reversed the resistance to trastuzumab in TR cell lines and suppressed cell invasion and migration. Dysregulation of transforming growth factor beta (TGF-ß) was detected when the expression of CDK8 was silenced by CDK8 siRNA, and downregulation of TGF-ß had a notable effect on reducing the phosphorylation of SMAD2/SMAD3. CONCLUSION: miR-141-3p could restore the sensitivity to trastuzumab in breast cancer cells by repressing CDK8, which might regulate the phosphorylation levels of SMAD2/SMAD3 via TGF-ß.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Quinase 8 Dependente de Ciclina/metabolismo , MicroRNAs/metabolismo , Transdução de Sinais , Trastuzumab/uso terapêutico , Animais , Sequência de Bases , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação para Baixo/genética , Resistencia a Medicamentos Antineoplásicos , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Invasividade Neoplásica , Fator de Crescimento Transformador beta/metabolismo , Trastuzumab/farmacologia
8.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 44(12): 1344-1352, 2019 Dec 28.
Artigo em Zh | MEDLINE | ID: mdl-31969498

RESUMO

OBJECTIVE: To examine the expression of vasohibin-1, metastasis-associated in colon cancer-1 (MACC1) and KAI1 proteins in serous ovarian cancer and their clinical significance.
 Methods: In 124 specimens of serous ovarian cancer (serous ovarian cancer group) and 30 specimens of ovarian serous cystadenoma (ovarian serous cystadenoma group), the expression of vasohibin-1, MACC1 and KAI1 protiens were detected by immunohistochemistry ElivisionTM method.
 Results: In the serous ovarian cancer group, the positive rates of vasohibin-1 and MACC1 proteins were 48.4% and 58.1%, respectively, which were both higher than those in the ovarian serous cystadenoma group (10.0% and 13.3%, respectively); while the positive rate of KAI1 protein in the serous ovarian cancer group was 33.9%, which was lower than that in the ovarian serous cystadenoma group (86.7%), there were significant differences between the 2 groups (all P<0.05). In the serous ovarian cancer group, the expression of the 3 proteins were closely related to the pathological grade, Federation International of Gynecology and Obstetrics (FIGO) stage and pelvic lymph node metastasis (all P<0.05). The KAI1 protein was negatively correlated with the levels of vasohibin-1 and MACC1 (r=-0.500, -0.600, respectively, both P<0.01); while there was a positive correlation between the vasohibin-1 and the MACC1 (r=0.518, P<0.01). Kaplan-Meier survival analysis showed that the over-expression of vasohibin-1, MACC1 and the low-expression of KAI1 protein were related to the survival rates (all P<0.05). Multi-factor analysis showed that the expression of vasohibin-1, KAI1 protein and the FIGO stage were independent prognosis factors for radical operation of serous ovarian cancer (RR=2.185, 3.893, 0.413; 95% CI=1.263-3.779, 2.190-6.921, 0.251-0.681; all P<0.05).
 Conclusion: The up-regulation of vasohibin-1, MACC1 and down-regulation of KAI1 in serous ovarian cancer are related to the tumor differentiation, clinical stage, metastasis and prognosis. Combined detection of these indexes is useful in predicting the progression and prognosis of serous ovarian cancer.


Assuntos
Carcinoma Epitelial do Ovário , Neoplasias Ovarianas , Proteínas de Ciclo Celular , Neoplasias do Colo , Feminino , Humanos , Proteína Kangai-1 , Estadiamento de Neoplasias , Prognóstico , Transativadores , Fatores de Transcrição
9.
Scand J Gastroenterol ; 53(7): 769-776, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29852786

RESUMO

OBJECTIVE: To clarify the relative expression and molecular function of microRNA (miR)-145 in esophageal cancer and understand its mechanistic involvement in this disease. MATERIAL AND METHODS: The relative expression of miR-145 in clinical samples was analyzed using the public GSE43732 dataset. The prognostic analysis with respect to miR-145 expression was performed with Kaplan-Meier plot. Cell viability was measured by MTT assay and the anchorage-independent growth was evaluated by soft agar assay. The migration and invasion of esophageal cancer cells were measured using transwell chamber. The regulatory effect of miR-145 on SMAD5 was determined by dual-luciferase reporter assay. The endogenous SMAD5 protein was measured by Western blot. RESULTS: We demonstrated high expression of miR-145 associated with late stage and unfavorable prognosis of esophageal cancer. Ectopic expression of miR-145 mimic significantly stimulated cell proliferation and anchorage-independent growth. Furthermore, high level of miR-145 significantly promoted both migration and invasion in vitro. Notably, we identified SMAD5 as direct target of miR-145, the suppressed expression of which consequently led to increased cell proliferation and migration/invasion. CONCLUSION: Our study uncovered the crucial role of miR-145/SMAD5 in esophageal cancer and highlighted its target potential for diagnostic and therapeutic purpose.


Assuntos
Neoplasias Esofágicas/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Proteína Smad5/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Sobrevivência Celular , Neoplasias Esofágicas/patologia , Humanos , Metástase Linfática/genética , Prognóstico
10.
BMC Surg ; 17(1): 47, 2017 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-28431527

RESUMO

BACKGROUND: Metastasis and recurrence are the most common reasons for treatment failure of colorectal carcinoma (CRC). Vasculogenic mimicry (VM, blood supply formation often seen in highly aggressive tumors), Aldehyde dehydrogenase 1 (ALDH1, a biomarker of cancer stem cells), KAI1 (a suppressor gene of tumor metastasis) are all valuable factors for metastasis and prognosis in diverse human cancers. However, the correlation of VM, ALDH1, KAI1 and microvessel density (MVD) in CRC is unclear. In this study, we analyzed the correlations among VM, ALDH1, KAI1 and MVD, as well as their respective correlations with clinicopathological parameters and survival in CRC. METHODS: The level of VM, ALDH1, KAI1 and MVD in 204 whole tissue samples of CRC were examined by immunhistochemistry. Clinical data was also collected. RESULTS: Levels of VM, ALDH1 and MVD were significantly higher, and levels of KAI1 significantly lower, in CRC tissues than in normal colorectal tissues. Levels of VM, ALDH1 and MVD were positively associated with invasion of depth, lymph node metastasis (LNM), distant metastasis and tumor-node-metastasis (TNM) stages, and negatively with patients' overall survival (OS). Levels of KAI1 was negatively correlated with invasion of depth, LNM, distant metastasis and TNM stages, and the KAI1 positive expression subgroup had significantly longer OS than did the KAI1- subgroup. In multivariate analysis, high levels of VM, ALDH1 and KAI1, as well as TNM stages were independently correlated with lower OS in patients with CRC. CONCLUSIONS: VM, MVD and the expression of ALDH1 and KAI1 may represent promising metastatic and prognostic biomarkers, as well as potential therapeutic targets for CRC.


Assuntos
Neoplasias Colorretais/patologia , Isoenzimas/metabolismo , Microvasos/metabolismo , Retinal Desidrogenase/metabolismo , Adulto , Idoso , Família Aldeído Desidrogenase 1 , Feminino , Humanos , Proteína Kangai-1/metabolismo , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Prognóstico
11.
BMC Cancer ; 16(1): 876, 2016 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-27832750

RESUMO

BACKGROUND: Tumor recurrence and metastasis are the most common reason for treatment failure. Metastasis-associate in colon cancer-1 (MACC1) has been identified as a metastatic and prognostic biomarker for colorectal cancer and other solid tumors. Aldehyde dehydrogenase 1 (ALDH1), a marker of cancer stem cells, is also associated with metastasis and poor prognosis in many tumors. However, the prognostic value of either MACC1 or ALDH1 in non-small cell lung cancer (NSCLC) is unclear. In this study, we explored the relationship between MACC1 and ALDH1 expression, as well as their respective associations with clinicopathological features, to determine if either could be useful for improvement of survival prognosis in NSCLC. METHODS: The expression levels of both MACC1 and ALDH1 in 240 whole tissue sections of NSCLC were examined by immunohistochemistry. Clinical data were also collected. RESULTS: MACC1 and ALDH1 were significantly overexpressed in NSCLC tissues when compared to levels in normal lung tissues. Investigation of associations between MACC1 or ALDH1 protein levels with clinicopathological parameters of NSCLC revealed correlations between the expression of each with tumor grade, lymph node metastasis, and tumor node metastasis. The overall survival of patients with MACC1- or ALDH1-positive NSCLC tumors was significantly lower than that of those who were negative. Importantly, multivariate analysis suggested that positive expression of either MACC1 or ALDH1, as well as TNM stage, could be independent prognostic factors for overall survival in patients with NSCLC. CONCLUSIONS: MACC1 and ALDH1 may represent promising metastatic and prognostic biomarkers, as well as potential therapeutic targets, for NSCLC.


Assuntos
Adenocarcinoma/secundário , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/secundário , Carcinoma de Células Escamosas/secundário , Isoenzimas/metabolismo , Neoplasias Pulmonares/patologia , Retinal Desidrogenase/metabolismo , Fatores de Transcrição/metabolismo , Adenocarcinoma/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Família Aldeído Desidrogenase 1 , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma de Células Escamosas/metabolismo , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Neoplasias Pulmonares/metabolismo , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida , Transativadores
12.
World J Surg Oncol ; 14(1): 276, 2016 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-27793161

RESUMO

BACKGROUND: The most common reason for malignant tumor treatment failure is recurrence and metastasis. Metastasis-associated in colon cancer-1 (MACC1) was originally identified as a metastatic and prognostic biomarker for colon cancer and later other solid tumors. Kangai 1 (KAI1), a marker of suppressor of metastasis, is also associated with metastasis and poor prognosis in many tumors. However, the prognostic value of either MACC1 or KAI1 in gastric adenocarcinoma (GAC) is unclear. In this study, we explored the relationship between MACC1 and KAI1 expression, as well as their respective correlation with clinicopathological features, to determine if either could be helpful for improvement of survival prognosis in GAC patients. METHODS: The expression levels of both MACC1 and KAI1 in 325 whole-tissue sections of GAC were examined by immunohistochemistry. Clinical data was also collected. RESULTS: MACC1 was significantly overexpressed in GAC tissues when compared to levels in normal gastric tissues; KAI1 was significantly down-expressed in GAC tissues when compared to levels in normal gastric tissues. Investigation of association between MACC1 and KAI1 protein levels with clinicopathological parameters of GAC indicated association between the expression of each with tumor grade, lymph node metastasis, invasive depth, and TNM stages. The overall survival time of patients with MACC1- or KAI1-positive GAC tumors was significantly shorter or longer than that of those who were negative. Importantly, multivariate analysis suggested that positive expression of either MACC1 or KAI1, as well as TNM stage, could be independent prognostic factors for overall survival in patients with GAC. CONCLUSIONS: MACC1 and KAI1 may represent promising metastatic and prognostic biomarkers, as well as potential therapeutic targets, for GAC.


Assuntos
Adenocarcinoma/secundário , Biomarcadores Tumorais/metabolismo , Proteína Kangai-1/metabolismo , Neoplasias Gástricas/patologia , Fatores de Transcrição/metabolismo , Adenocarcinoma/metabolismo , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Neoplasias Gástricas/metabolismo , Taxa de Sobrevida , Transativadores
13.
Luminescence ; 31(1): 281-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26081829

RESUMO

We describe a signal amplification assay for the simultaneous detection of HIV-1 and HIV-2 via a quantum dot (QD) layer-by-layer assembled polystyrene microsphere (PS) composite in a homogeneous format. The crucial point of this composite is the core-shell system. PS is utilized as the core and QDs as the shell. Based on the high affinity of streptavidin and biotin, QDs are assembled layer-by-layer on the surface of the PS as amplification labels. Biotinylated reporter probe is combined with the PS-QDs conjugate and then hybridized with target DNA immobilized on the surface of a 96-well plate. Using this approach, each target DNA corresponds to a large number of QDs and the fluorescence signal is greatly enhanced. Two QD colors (605 and 655 nm) are used to detect dual-target DNAs simultaneously. Taking advantage of the enzyme-free reaction and high sensitivity, this PS-QD-based sensor can be used in simple 'mix and detection' assays. Our results show that this technology has potential application in rapid point-of-care testing, gene expression studies, high-throughput screening and clinical diagnostics.


Assuntos
DNA Viral/análise , HIV-1/isolamento & purificação , HIV-2/isolamento & purificação , Pontos Quânticos , HIV-1/química , HIV-2/química , Microesferas , Poliestirenos/química , Espectrometria de Fluorescência
14.
World J Surg Oncol ; 13: 234, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26231404

RESUMO

BACKGROUND: KAI1 and epithelial-mesenchymal transition (EMT) is related to both angiogenesis and lymphangiogenesis and is an important target in new cancer treatment strategies. We aimed to investigate the KAI1 and marker of EMT expression and correlation with lymph node metastasis (LNM) and explore their prognostic impact in non-small cell lung cancer (NSCLC). METHODS: Tumor tissue specimens from 312 resected patients with stage I-IIIA NSCLC were obtained. Immunohistochemistry was used to assess the expression of the molecular markers KAI1, E-cadherin (E-cad), vimentin, CD34, and D2-40. RESULTS: There were 153 N0 and 159 N+ patients. Tumor cell expression of KAI1and the marker of EMT, lymphatic vessel density (LVD), and microvessel density (MVD) were related to LNM. In multivariate analyses, the ages of patients, high tumor cell KAI1 expression, EMT, and the scores of MVD were independent factor of prognosis. CONCLUSIONS: Tumor cell KAI1 expression, EMT, LVD, and MVD correlate with LNM. Thus, the detection of KAI1, expression of markers of EMT, and the scores of MVD may be used as a potential indicator of NSCLC prognosis.


Assuntos
Adenocarcinoma/patologia , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Grandes/patologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/patologia , Transição Epitelial-Mesenquimal , Proteína Kangai-1/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidade , Caderinas/metabolismo , Carcinoma de Células Grandes/metabolismo , Carcinoma de Células Grandes/mortalidade , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/mortalidade , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Linfangiogênese , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Vimentina/metabolismo
15.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 45(1): 43-8, 2014 Jan.
Artigo em Zh | MEDLINE | ID: mdl-24527580

RESUMO

OBJECTIVE: To seek good markers to predict invasion and metastasis of gastric adenocarcinoma (GAC). METHODS: Expression of Kangai 1 (KAI1), CD34, and D2-40 were examined by immunohistochemistry containing 145 specimens of GAC and 50 specimens of normal gastric tissue. Microvessel density (MVD) and lymph vessel density (LVD) were determined by the mean number of small CD34-positive or D2-40-positive vessels counted. And the relationship of KAI1, MVD and LVD, as well as the role of them on invasion, metastasis and prognosis in GAC were analyzed. RESULTS: The positive rate of KAI1, the median scores of MVD and LVD in normal gastric tissue and GAC tissue were 92.0%, (9.2 +/- 7.8)/LP, (7.5 +/- 7.6)/LP and 37.2%, (21.6 +/- 9. 1)/ LP, (22.6 +/- 12.7)/LP, respectively. And there was a significant different between the two groups (P < 0.05). The expression of KAI1, the scores of MVD and LVD were significantly related with pathologic-tumor-node metastasis (pTNM) stages, depth of invation and lymph node metastasis (all P < 0.05). There was a significant relationship between the expression of KAI1 and the scores of MVD or LVD. The survival rate of the KAI1-positive or KAI1-negative group was significantly different (P < 0.01); the survival rates were significantly lower in MVD > or = 22's group than that in MVD < 22's group, so was the same relationship between the LVD > or = 23's group and the LVD < 23's group (both P < 0.01). Cox regression analysis: pTNM stage, expression of KAI1, and the scores of MVD were independent factors of postoperative survival time in GAC (P < 0.05). CONCLUSION: The combined detection of KAI1, CD34, and D2-40 has an important role in predicting the progression and prognosis of GAC.


Assuntos
Adenocarcinoma/metabolismo , Proteína Kangai-1/metabolismo , Linfangiogênese , Neovascularização Patológica , Neoplasias Gástricas/metabolismo , Adenocarcinoma/patologia , Progressão da Doença , Humanos , Metástase Linfática , Vasos Linfáticos , Prognóstico , Neoplasias Gástricas/patologia , Taxa de Sobrevida
16.
Plants (Basel) ; 12(13)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37447022

RESUMO

Paeonia ostii is an important woody oil crop mainly cross-pollinated. However, the low yield has become an important factor restricting the industrial development of P. ostii. Cross-pollination has become one of the important measures to increase the seed yield. Therefore, conservation of pollen with high vitality is crucial to ensure successful pollination of P. ostii. In this study, we found an effective methodological system to assess the viability, ability to germinate, and optimal storage conditions of P. ostii pollen grains. The optimal medium in vitro was 50 g/L sucrose, 100 mg/L boric acid, 50 g/L PEG6000, 100 mg/L potassium nitrate, 300 mg/L calcium nitrate, and 200 mg/L magnesium sulfate at pH 5.4. Optimal germination condition in vitro was achieved at 25 °C for 120 min, allowing easy observation of the germination percentage and length of the pollen tubes. In addition, the viability of pollen grains was assessed by comparing nine staining methods. Among them, MTT, TTC, benzidine-H2O2, and FDA were effective to distinguish between viable and non-viable pollen, and the results of the FDA staining method were similar to the pollen germination percentage in vitro. After evaluation of pollen storage, thawing and rehydration experiments showed that thawing at 4 °C for 30 min and rehydration at 25 °C for 30 min increased the germination percentage of pollen grains stored at low temperatures. The low-temperature storage experiments showed that 4 °C was suitable for short-term storage of P. ostii pollen grains, while -80 °C was suitable for long-term storage. This is the first report on the in vitro germination, viability tests, and storage of P. ostii pollen grains, which will provide useful information for P. ostii germplasm conservation and artificial pollination.

17.
Micromachines (Basel) ; 14(11)2023 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-38004982

RESUMO

Two-dimensional (2D) materials, characterized by their atomically thin nature and exceptional properties, hold significant promise for future nano-electronic applications. The precise control of carrier density in these 2D materials is essential for enhancing performance and enabling complex device functionalities. In this study, we present an electron-beam (e-beam) doping approach to achieve controllable carrier doping effects in graphene and MoS2 field-effect transistors (FETs) by leveraging charge-trapping oxide dielectrics. By adding an atomic layer deposition (ALD)-grown Al2O3 dielectric layer on top of the SiO2/Si substrate, we demonstrate that controllable and reversible carrier doping effects can be effectively induced in graphene and MoS2 FETs through e-beam doping. This new device configuration establishes an oxide interface that enhances charge-trapping capabilities, enabling the effective induction of electron and hole doping beyond the SiO2 breakdown limit using high-energy e-beam irradiation. Importantly, these high doping effects exhibit non-volatility and robust stability in both vacuum and air environments for graphene FET devices. This methodology enhances carrier modulation capabilities in 2D materials and holds great potential for advancing the development of scalable 2D nano-devices.

18.
Analyst ; 137(7): 1611-7, 2012 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-22343986

RESUMO

A new quantum dot-based method to detect specific sequences of DNA is proposed. The capture and reporter probes do not hybridize to each other, but in the presence of a template they can anneal to each other via the formation of a stable ternary complex. Because of the specific design of the capture and reporter probes, the 5' end of the template target DNA remains free to hybridize with another reporter. In this way, each capture DNA is an initiator strand that triggers a cascade of hybridization events between the target DNA and the reporter probe. This forms a superstructure, enhances base stacking, and produces a strong fluorescent signal. The introduction of T4 DNA ligase further stabilizes the superstructure and greatly increases the fluorescence intensity, and the detection limit is as low as 10 fM. This fluorescence method is advantageous over conventional techniques because of its excellent ability to discriminate single base-pair mismatches and single nucleotide gap or flap. This simple technique is promising for improving medical diagnosis and treatment.


Assuntos
Técnicas Biossensoriais/métodos , DNA/química , Pontos Quânticos , Sequência de Bases , Eletroforese em Gel Bidimensional , Fluorescência , Dados de Sequência Molecular , Hibridização de Ácido Nucleico
19.
Analyst ; 137(6): 1396-401, 2012 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-22318238

RESUMO

We introduce here a novel assay for the detection of platelet-derived growth factor BB (PDGF-BB) via hybridization chain reaction (HCR) based on an aptameric system, where stable DNA monomers assemble only upon exposure to a target PDGF-BB aptamer. In this process, two complementary stable species of biotinylated DNA hairpins coexist in solution until the introduction of initiator aptamer strands triggers a cascade of hybridization events that yields nicked double helices analogous to alternating copolymers. In detail, the aptamer firstly opens the hairpins in the solution, creating long concatemers, and then reacts with the antibody captured PDGF-BB on the well surface. Moreover, several experimental conditions including different PDGF-BB aptamers, the spacer length of the selected aptamer and hairpin, etc. are investigated and optimized. Our results show that the coupling of HCR to aptamer triggers for the amplification detection of PDGF-BB achieves a better performance in the fluorescence detection of PDGF-BB as compared to the traditional antibody-antigen-aptamer assays. Upon modification, the approach presented herein could be extended to detect other types of targets. We believe such advancements will represent a significant step towards improved diagnostics and more personalized medical treatment and environmental monitoring.


Assuntos
Aptâmeros de Nucleotídeos/química , Bioensaio/métodos , Proteínas Proto-Oncogênicas c-sis/análise , Becaplermina , DNA/química , DNA/genética , Humanos , Hibridização Genética , Conformação de Ácido Nucleico , Sensibilidade e Especificidade , Espectrometria de Fluorescência/métodos
20.
Sheng Li Xue Bao ; 64(6): 657-65, 2012 Dec 25.
Artigo em Zh | MEDLINE | ID: mdl-23258329

RESUMO

The aim of the present study is to explore whether vasculogenic mimicry (VM) and bacterial L-form infection exist in human epithelial ovarian cancer (EOC) or not and to elucidate the correlation of L-form infection, expression of hypoxia inducible factor 1α (HIF-1α)/MMP-9 and VM. In 87 specimens of EOC and 20 specimens of ovarian benign epithelial tumor tissues, L-form infection was detected by Gram's staining, expression of HIF-1α/MMP-9 and VM were detected by immunohistochemical and histochemical staining. The results showed that the positive rates of HIF-1α and MMP-9 protein in EOC were 52.9% and 66.7%, while in benign epithelial tumor tissues, the positive rates were 10.0% and 10.0% respectively, and there were significant differences between them (P < 0.05). In EOC and benign epithelial tumor tissues, L-form infections ratios were 24.1% and 0, respectively, and the difference was also significant (P < 0.01). Expression of VM, HIF-1α and MMP-9 in EOC was significantly related to differentiation, abdominal implantation and lymph node metastasis and FIGO stage (P < 0.01). L-form infection had relationship with abdominal implantation, lymph node metastasis and FIGO stage (P < 0.01 or 0.05). The expression of HIF-1α had positive relationship with expression of MMP-9 and VM (r = 0.505, 0.585, respectively, P < 0.01); there was also a positive relationship between MMP-9 expression and VM (r = 0.625, P < 0.01). Overexpression of VM, HIF-1α and MMP-9 were related to poor prognosis: the survival rates were significantly lower in positive patients than those in negative patients (P < 0.05). And the group with L-form infection also had poor prognosis: the survival rates were lower than those in group without infection (P < 0.05). FIGO stage, expression of VM, HIF-1α and MMP-9 were independent prognosis factors of EOC (P < 0.05). The results suggest that L-form infection, the expression of HIF-1α, MMP-9 and VM in EOC are related to differentiation, lymph node metastasis, clinical stage and prognosis. Combined detection of these indexes has an important role in predicting the progression and prognosis of EOC.


Assuntos
Infecções Bacterianas/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Formas L/patogenicidade , Metaloproteinase 9 da Matriz/metabolismo , Neoplasias Epiteliais e Glandulares/patologia , Neovascularização Patológica , Neoplasias Ovarianas/patologia , Infecções Bacterianas/microbiologia , Carcinoma Epitelial do Ovário , Feminino , Humanos , Neoplasias Epiteliais e Glandulares/metabolismo , Neoplasias Epiteliais e Glandulares/microbiologia , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/microbiologia , Prognóstico
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