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1.
Opt Lett ; 49(3): 570-573, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300061

RESUMO

Recently, there has been significant interest in the generation of coherent temporal solitons in optical microresonators. In this Letter, we present a demonstration of dissipative Kerr soliton generation in a microrod resonator using an auxiliary-laser-assisted thermal response control method. In addition, we are able to control the repetition rate of the soliton over a range of 200 kHz while maintaining the pump laser frequency, by applying external stress tuning. Through the precise control of the PZT voltage, we achieve a stability level of 3.9 × 10-10 for residual fluctuation of the repetition rate when averaged 1 s. Our platform offers precise tuning and locking capabilities for the repetition frequency of coherent mode-locked combs in microresonators. This advancement holds great potential for applications in spectroscopy and precision measurements.

2.
Ann Transl Med ; 11(2): 110, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36819581

RESUMO

Background: Doppler ultrasonography is used to study ovarian vascular characteristics. However, the outcomes are reported with a considerable variability in literature. Here we review the differences in Doppler ultrasound-measured ovarian blood flow indices between women with and without ovarian dysfunction and seeks correlations between Doppler measures and ovarian markers. Methods: A literature search was conducted in electronic databases (Google Scholar, Ovid, PubMed, Science Direct, and Springer) to identify studies that used Doppler for ovarian blood flow examination and reported Doppler measures in women with and without ovarian dysfunction and/or the correlations between wDoppler indices and markers of ovarian dysfunction. After quality assessment of included studies, a meta-analysis of weighted mean differences (WMDs) between women with and without ovarian dysfunction in vascularization index (VI), flow index (FI), vascularization flow index (VFI), pulsatility index (PI) and resistance index (RI) was performed. Correlation coefficients between Doppler indices and markers of ovarian dysfunction were pooled to achieve overall estimates. Results: A total of 27 studies [2,377 women with ovarian dysfunction and 308 controls; age 27.7 years, 95% confidence interval (CI): 26.4 to 29.1] were included. These studies were of moderate quality. The VI (WMD 9.75; P<0.0001), FI (WMD 2.73; P<0.0001), and VFI (WMD 1.29; P<0.0001) were significantly higher whereas PI (WMD -1.08; P=0.001) and RI (WMD -0.26; P<0.0001) were significantly lower in women with polycystic ovarian syndrome (PCOS) than in normal women. In women undergoing in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI), antral follicle count was positively correlated with VI (r=0.24; P=0.001), FI (r=0.42; P<0.0001), and VFI (r=0.25; P=0.002). In women with PCOS, testosterone had statistically non-significant correlations with VI (r=0.40; P=0.081), and VFI (r=0.39; P=0.063) and was inversely correlated with PI (r=-0.30; P<0.0001) and RI (r=-0.48; P<0.0001). In women with PCOS, luteinizing hormone (LH) was inversely correlated with PI (r=-0.26; P=0.086) and RI (r=-0.25; P=0.007). Conclusions: Doppler indices are found significantly different in women with and without ovarian dysfunction and have significant correlations with markers of ovarian dysfunction. These results support the use of Doppler ultrasound to examine ovarian dysfunction. High statistical heterogeneity observed herein should be studies in future investigations.

4.
Saudi J Gastroenterol ; 24(1): 59-66, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29451186

RESUMO

Background/Aims: Probiotics play a role in relieving irritable bowel syndrome (IBS); however, the underlying mechanism is yet unclear. The aim of the study was to investigate the effects of the supernatants of Lactobacillus acidophilus and Bifidobacterium longum on the expression of serotonin transporter (SERT) messenger ribonucleic acid (mRNA) and protein. Materials and Methods: HT-29 and Caco-2 cells were treated with different concentrations of L. acidophilus and B. longum supernatants for 12 h and 24 h, respectively. SERT mRNA and proteins levels were detected by real-time polymerase chain reaction (real-time PCR) and Western-blotting. Results: The mRNA levels of SERT in HT-29 and Caco-2 cells treated with different concentrations of L. acidophilus or B. longum supernatants for 12 h and 24 h, each, were higher than that in the control groups. In addition, the expression of the protein in both cells was also upregulated, which was approximately similar to that of the corresponding mRNA. Conclusions: L. acidophilus and B. longum supernatants can upregulate SERT mRNA and protein levels in intestinal epithelial cells.


Assuntos
Bifidobacterium longum/metabolismo , Mucosa Intestinal/metabolismo , Lactobacillus acidophilus/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Regulação para Cima , Células CACO-2 , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Células HT29 , Humanos , Intestinos/citologia , Síndrome do Intestino Irritável/dietoterapia , Síndrome do Intestino Irritável/metabolismo , Probióticos/metabolismo , Probióticos/farmacologia , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética
5.
Exp Ther Med ; 15(3): 2575-2582, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29456661

RESUMO

Cervical cancer is one of the primary causes of cancer-associated mortality worldwide. Due to the increasing incidence of cervical cancer, multiple treatment options are required. Initial responses to chemotherapy and surgical interventions are generally positive, however patients often experience relapse and tumor recurrence. Currently, the effects of cucurbitacins on different types of cancer are being investigated, as they exhibit a wide variety of bioactivities. The anticancer activity of the cucurbitacin 23,24-dihydrocucurbitacin B against a panel of human cervical cancer cell lines was investigated in the current study. Cell viability was determined using an MTT assay and apoptosis was detected using DAPI staining. The proportion of apoptotic cells, cell cycle distribution, mitochondrial membrane potential (ΔΨm) and reactive oxygen species (ROS) levels were estimated using flow cytometry. Protein expression was determined using western blot analysis. The results of the current study indicated that 23,24-dihydrocucurbitacin B inhibited the viability of human cervical cancer cell lines and had an IC50 of 40-60 µM. However, its cytotoxic effects were much less pronounced in normal epithelial fr2 and HerEpiC cells, where it had an IC50 of 125 µM. The underlying mechanisms of this were further studied and the results demonstrated that 23,24-dihydrocucurbitacin B induced apoptosis in HeLa cells and caused ROS-mediated shifts in the ΔΨm. Additionally, it caused the cell cycle arrest of HeLa cells at the G2/M checkpoint. The phosphoinositide 3 kinase/protein kinase B/mechanistic target of rampamycin (PI3K/AKT/mTOR) cascade may serve an important role in cancer tumorigenesis, progression and resistance to chemotherapy. The results indicated that 23,24-dihydrocucurbitacin B significantly decreased the expression of important proteins in the PI3K/Akt/mTOR cascade. Taken together, these results suggest that 23,24-dihydrocucurbitacin B may be novel method of treating cervical cancer.

6.
J Huazhong Univ Sci Technolog Med Sci ; 37(1): 122-130, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28224420

RESUMO

In our previous studies, a novel cortex-like TiO2 coating was prepared on Ti surface through micro-arc oxidation (MAO) by using sodium tetraborate as electrolyte, and the effects of the coating on cell attachment were testified. This study aimed to investigate the effects of this cortex-like MAO coating on osseointegration. A sand-blasting and acid-etching (SLA) coating that has been widely used in clinical practice served as control. Topographical and chemical characterizations were conducted by scanning electron microscopy, energy dispersive X-ray spectrometer, X-ray diffraction, contact angle meter, and step profiler. Results showed that the cortex-like coating had microslots and nanopores and it was superhydrophilic, whereas the SLA surface was hydrophobic. The roughness of MAO was similar to that of SLA. The MAO and SLA implants were implanted into the femoral condyles of New Zealand rabbits to evaluate their in-vivo performance through micro-CT, histological analysis, and fluorescent labeling at the bone-implant interface four weeks after surgery. The micro-CT showed that the bone volume ratio and mean trabecular thickness were similar between MAO and SLA groups four weeks after implantation. Histological analysis and fluorescent labeling showed no significant differences in the bone-implant contact between the MAO and SLA surfaces. It was suggested that with micro/nanostructure and superhydrophilicity, the cortex-like MAO coating causes excellent osseointegration, holding a promise of an application to implant modification.


Assuntos
Materiais Revestidos Biocompatíveis/farmacologia , Fêmur/diagnóstico por imagem , Osseointegração/efeitos dos fármacos , Titânio/química , Animais , Materiais Revestidos Biocompatíveis/química , Fêmur/cirurgia , Implantes Experimentais , Microscopia Eletrônica de Varredura , Oxirredução , Coelhos , Propriedades de Superfície , Titânio/farmacologia , Difração de Raios X , Microtomografia por Raio-X
7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-238406

RESUMO

In our previous studies,a novel cortex-like TiO2 coating was prepared on Ti surface through micro-arc oxidation (MAO) by using sodium tetraborate as electrolyte,and the effects of the coating on cell attachment were testified.This study aimed to investigate the effects of this cortex-like MAO coating on osseointegration.A sand-blasting and acid-etching (SLA) coating that has been widely used in clinical practice served as control.Topographical and chemical characterizations were conducted by scanning electron microscopy,energy dispersive X-ray spectrometer,X-ray diffraction,contact angle meter,and step profiler.Results showed that the cortex-like coating had microslots and nanopores and it was superhydrophilic,whereas the SLA surface was hydrophobic.The roughness of MAO was similar to that of SLA.The MAO and SLA implants were implanted into the femoral condyles of New Zealand rabbits to evaluate their in-vivo performance through micro-CT,histological analysis,and fluorescent labeling at the bone-implant interface four weeks after surgery.The micro-CT showed that the bone volume ratio and mean trabecular thickness were similar between MAO and SLA groups four weeks after implantation.Histological analysis and fluorescent labeling showed no significant differences in the bone-implant contact between the MAO and SLA surfaces.It was suggested that with micro/nanostructure and superhydrophilicity,the cortex-like MAO coating causes excellent osseointegration,holding a promise of an application to implant modification.

8.
Chin Med J (Engl) ; 129(20): 2427-2433, 2016 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-27748334

RESUMO

BACKGROUND: Colorectal serrated polyp is considered as histologically heterogeneous lesions with malignant potential in western countries. However, few Asian studies have investigated the comprehensive clinical features of serrated polyps in symptomatic populations. The aim of the study was to evaluate the features of colorectal serrated polyps in a Chinese symptomatic population. METHODS: Data from all consecutive symptomatic patients were documented from a large colonoscopy database and were analyzed. Chi-square test or Fisher's exact test and logistic regression analysis were used for the data processing. RESULTS: A total of 9191 (31.7%) patients were detected with at least one colorectal polyp. The prevalence of serrated polyps was 0.53% (153/28,981). The proportions of hyperplastic polyp (HP), sessile serrated adenoma/polyp (SSA/P), and traditional serrated adenoma (TSA) of all serrated polyps were 41.2%, 7.2%, and 51.6%, respectively, which showed a lower proportion of HP and SSA/P and a higher proportion of TSA. Serrated polyps appeared more in males and elder patients while there was no significant difference in the subtype distribution in gender and age. The proportions of large and proximal serrated polyps were 13.7% (21/153) and 46.4% (71/153), respectively. In total, 98.9% (89/90) serrated adenomas were found with dysplasia. Moreover, 14 patients with serrated polyps were found with synchronous advanced colorectal neoplasia, and large serrated polyps (LSPs) (odds ratio: 3.446, 95% confidence interval: 1.010-11.750, P < 0.05), especially large HPs, might have an association with synchronous advanced neoplasia (AN). CONCLUSIONS: The overall detection rate of colorectal serrated polyps in Chinese symptomatic patient population was low, and distribution pattern of three subtypes is different from previous reports. Moreover, LSPs, especially large HPs, might be associated with an increased risk of synchronous AN.


Assuntos
Neoplasias do Colo/diagnóstico , Neoplasias do Colo/epidemiologia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/epidemiologia , Adulto , Distribuição por Idade , Idoso , Distribuição de Qui-Quadrado , Colonoscopia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Prevalência
9.
Chem Asian J ; 11(2): 256-64, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26541628

RESUMO

Based on anisometric noble-metal nanocrystals, a universal fabrication protocol for preparing 3D supercrystals with controlled orientation on a chip has been developed. A comparison of the surface-enhanced Raman scattering (SERS) behavior of 3D nanorod supercrystals aligned vertically and parallel to the chip indicates that the SERS-enhancing ability and reproducibility of the former is superior to the latter. The 3D nanorod supercrystals aligned vertically to the chip have been utilized as highly sensitive SERS substrates for the label-free discrimination of Gram-positive and -negative bacteria. Furthermore, to strengthen the stability of the supercrystal substrate for assays of bacteria in biosamples, a coating of the antibiotic vancomycin can dramatically increase adhesion of bacteria on a nanointerface and simultaneously improve the SERS response of bacteria to achieve a layer-by-layer assembled, stable, and reliable biosensor for bacteria.


Assuntos
Técnicas Biossensoriais , Metais/química , Nanoestruturas , Salmonella/isolamento & purificação , Staphylococcus/isolamento & purificação , Microscopia Eletrônica de Varredura , Análise Espectral Raman , Propriedades de Superfície , Tensoativos , Vancomicina/química
10.
Scand J Gastroenterol ; 51(5): 572-82, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26691157

RESUMO

OBJECTIVE: Colorectal cancer (CRC) is the third leading cause of cancer-related mortality in the United States. Recent cancer genome-sequencing efforts and complementary functional studies have led to the identification of a collection of candidate 'driver' genes involved in CRC tumorigenesis. Tripartite motif (TRIM3) is recently identified as a tumour suppressor in glioblastoma but this tumour-suppressive function has not been investigated in CRC. MATERIAL AND METHODS: In this study, we investigated the potential role of TRIM3 as a tumour suppressor in CRC development by manipulating the expression of TRIM3 in two authentic CRC cell lines, HCT116 and DLD1, followed by various functional assays, including cell proliferation, colony formation, scratch wound healing, soft agar, and invasion assays. Xenograft experiment was performed to examine in vivo tumour-suppressive properties of TRIM3. RESULTS: Small-interfering RNA (siRNA) mediated knockdown of TRIM3 conferred growth advantage in CRC cells. In contrast, overexpression of TRIM3 affected cell survival, cell migration, anchorage independent growth and invasive potential in CRC cells. In addition, TRIM3 was found to be down-regulated in human colon cancer tissues compared with matched normal colon tissues. Overexpression of TRIM3 significantly inhibited tumour growth in vivo using xenograft mouse models. Mechanistic investigation revealed that TRIM3 can regulate p53 protein level through its stabilisation. CONCLUSIONS: TRIM3 functions as a tumour suppressor in CRC progression. This tumour-suppressive function is exerted partially through regulation of p53 protein. Therefore, this protein may represent a novel therapeutic target for prevention or intervention of CRC.


Assuntos
Proteínas de Transporte/genética , Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Experimentais , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Animais , Apoptose , Proteínas de Transporte/biossíntese , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Feminino , Humanos , Immunoblotting , Imuno-Histoquímica , Camundongos , Camundongos Nus , Reação em Cadeia da Polimerase em Tempo Real
11.
Acta Pharmacol Sin ; 36(11): 1377-87, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26190499

RESUMO

AIM: To investigate whether the transfer of the IL-37b gene, a newly identified inhibitor of both innate and adaptive immunity, could improve the therapeutic efficacy of mesenchumal stromal cells (MSCs) in inflammatory bowel disease (IBD). METHODS: The expression of IL-37 in biopsied specimens of the patients with active ulcerative colitis (UC) was detected using RT-PCR and immunohistochemistry. Mice were treated with 3% dextran sulfate sodium (DSS) for 8 days to induce colitis. Before DSS treatment, the mice were injected with MSCs, MSC-eGFP or MSC-IL37b. Their body weight was measured each day, and the colons and spleens were harvested on d 10 for pathological and biochemical analyses. RESULTS: In biopsied specimens of the patients with active UC, the expression of IL-37 was dramatically elevated in inflamed mucosa, mainly in epithelial cells and infiltrating immune cells. Compared to MSC-eGFP or MSCs, MSC-IL37b administration significantly attenuated the body weight and colon length reduction, and decreased the histological score in DSS-induced colitis mice. Furthermore, MSC-IL37b administration increased the percentage of myeloid-derived suppressor cells (MDSCs) among total splenic mononuclear cells as well as the percentage of regulatory T cells (Tregs) among splenic CD4+ T cells in the mice. Moreover, MSC-IL37b administration increased the IL-2+ cells and decreased the IFN-γ+ cells among splenic CD4+ T cells. CONCLUSION: IL-37 is involved in the pathophysiology of UC. IL-37b gene transfer enhances the therapeutic efficacy of MSCs in DSS-induced colitis mice by inducing Tregs and MDSCs and regulating cytokine production.


Assuntos
Técnicas de Transferência de Genes , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/terapia , Interleucina-1/genética , Transplante de Células-Tronco Mesenquimais , Animais , Citocinas/análise , Sulfato de Dextrana , Modelos Animais de Doenças , Feminino , Terapia Genética , Humanos , Doenças Inflamatórias Intestinais/induzido quimicamente , Doenças Inflamatórias Intestinais/patologia , Transplante de Células-Tronco Mesenquimais/métodos , Camundongos , Camundongos Endogâmicos C57BL
12.
Acta Pharmacol Sin ; 36(4): 528-34, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25832432

RESUMO

AIM: IL-37b has shown anti-cancer activities in addition to its anti-inflammatory properties. In this study, we investigated the effects of IL-37b on breast carcinoma growth in mice and to determine the involvement of T cell activation in the effects. METHODS: IL-37b gene was transferred into mouse breast carcinoma cell line 4T1 (4T1-IL37b cells), the expression of secretory IL-37b by the cells was detected, and the effects of IL-37b expression on the cell proliferation in vitro was evaluated. After injection of 4T1 cells or 4T1-IL37b cells into immunocompetent BALB/c mice, immunodeficient BALB/c nude mice and NOD-SCID mice, the tumor growth and survival rate were measured. The proliferation of T cells in vitro was also detected. RESULTS: IL-37b was detected in the supernatants of 4T1-IL37b cells with a concentration of 12.02 ± 0.875 ng/mL. IL-37b expression did not affect 4T1 cell proliferation in vitro. BALB/c mice inoculated with 4T1-IL37b cells showed significant retardation of tumor growth. BALB/c mice inoculated with both 4T1 cells and mitomycin C-treated 4T1-IL37b cells also showed significant retardation of tumor growth. But the anti-cancer activity of IL-37b was abrogated in BALB/c nude mice and NOD-SCID mice inoculated with 4T1-IL37b cells. Recombinant IL-37b slightly promoted CD4(+) T cell proliferation without affecting CD8(+) T cell proliferation. CONCLUSION: IL-37b exerts anti-4T1 breast carcinoma effects in vivo by modulating the tumor microenvironment and influencing T cell activation.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Mama/patologia , Interleucina-1/genética , Interleucina-1/uso terapêutico , Animais , Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Técnicas de Transferência de Genes , Terapia Genética , Células HEK293 , Humanos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos SCID , Proteínas Recombinantes/genética , Proteínas Recombinantes/uso terapêutico , Linfócitos T/citologia , Linfócitos T/patologia
13.
World J Gastroenterol ; 21(1): 102-11, 2015 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-25574083

RESUMO

Intestinal dysbiosis is now known to be a complication in a myriad of diseases. Fecal microbiota transplantation (FMT), as a microbiota-target therapy, is arguably very effective for curing Clostridium difficile infection and has good outcomes in other intestinal diseases. New insights have raised an interest in FMT for the management of extra-intestinal disorders associated with gut microbiota. This review shows that it is an exciting time in the burgeoning science of FMT application in previously unexpected areas, including metabolic diseases, neuropsychiatric disorders, autoimmune diseases, allergic disorders, and tumors. A randomized controlled trial was conducted on FMT in metabolic syndrome by infusing microbiota from lean donors or from self-collected feces, with the resultant findings showing that the lean donor feces group displayed increased insulin sensitivity, along with increased levels of butyrate-producing intestinal microbiota. Case reports of FMT have also shown favorable outcomes in Parkinson's disease, multiple sclerosis, myoclonus dystonia, chronic fatigue syndrome, and idiopathic thrombocytopenic purpura. FMT is a promising approach in the manipulation of the intestinal microbiota and has potential applications in a variety of extra-intestinal conditions associated with intestinal dysbiosis.


Assuntos
Terapia Biológica/métodos , Fezes/microbiologia , Enteropatias/terapia , Intestinos/microbiologia , Microbiota , Animais , Terapia Biológica/efeitos adversos , Disbiose/microbiologia , Interações Hospedeiro-Patógeno , Humanos , Enteropatias/diagnóstico , Enteropatias/microbiologia , Resultado do Tratamento
14.
Gut Liver ; 8(5): 487-94, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25228972

RESUMO

BACKGROUND/AIMS: To investigate the differential expression of RING finger (RNF) proteins in Barrett esophagus (BE) and esophageal adenocarcinoma (EAC). METHODS: The differential expression of RNFs in normal esophagus (NE), BE, and EAC was screened using microarray assay. Real-time quantitative polymerase chain reaction (PCR), tissue micro-array assay, and Western blot analysis were independently performed to detect the mRNA and protein expression of screened RNFs. RESULTS: The expression of nine RNFs in the BE or EAC was 2-fold higher than those in NE. Among these proteins, the RNF32 and RNF121 expression in BE was 20.3-fold and 16.4-fold higher, respectively, than that in NE, and the expression of RNF24, RNF130, RNF141, RNF139, RNF11, RNF14, and RNF159 was upregulated more than 2-fold compared with NE. The expression of nine RNFs was not only upregulated in the EAC but was also positively related to the RNF expression in BE. The PCR results also indicated increased expression of these RNFs in BE and EAC compared to NE. Furthermore, the mRNA expression of all RNFs, except for RNF141 in EAC, was dramatically higher than those in the BE. Similar results were also obtained from the Western blot analysis. CONCLUSIONS: A total of nine RNFs play critical roles in the progression of BE to EAC.


Assuntos
Adenocarcinoma/enzimologia , Esôfago de Barrett/enzimologia , Neoplasias Esofágicas/enzimologia , Domínios RING Finger , Ubiquitina-Proteína Ligases/metabolismo , Adenocarcinoma/genética , Adulto , Idoso , Esôfago de Barrett/genética , Proteínas de Transporte/genética , Proteínas de Ligação a DNA , Progressão da Doença , Neoplasias Esofágicas/genética , Feminino , Perfilação da Expressão Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Pessoa de Meia-Idade , Proteínas/genética , Receptores de Superfície Celular/genética , Ubiquitina-Proteína Ligases/genética
15.
Appl Opt ; 52(32): 7759-68, 2013 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-24216735

RESUMO

A fiber with a thin-metallic layer introduced between the central core and the cladding is proposed to lift the near-degeneracy of the modes TE01, TM01, and HE21. It can be used to obtain the pure mode TE01 as both the active and passive fibers. In the case of the active fiber, the fiber with the appropriate rare earth doping profile in the central core is presented as the gain medium of a fiber laser. The numerical results show that the pure mode TE01 (99.99%) can be obtained. In the case of the passive fiber, Gaussian light beams with suitable shift distance from the center core are coupled into the fiber. The results indicate that only the mode TE01 remains with the increasing propagation distance.

16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(5): 1371-5, 2012 May.
Artigo em Chinês | MEDLINE | ID: mdl-22827092

RESUMO

A method of copper converting process determination based on PbO/PbS emission spectrum analysis was described. According to the known emission spectrum of gas molecules, the existence of PbO and PbS was confirmed in the measured spectrum. Through the field experiment it was determined that the main emission spectrum of the slag stage was from PbS, and the main emission spectrum of the copper stage was from PbO. The relative changes in PbO/PbS emission spectrum provide the method of copper converting process determination. Through using the relative intensity in PbO/PbS emission spectrum the copper smelting process can be divided into two different stages, i.e., the slag stage (S phase) and the copper stage (B phase). In a complete copper smelting cycle, a receiving telescope of appropriate view angle aiming at the converter flame, after noise filtering on the PbO/PbS emission spectrum, the process determination agrees with the actual production. Both the theory and experiment prove that the method of copper converting process determination based on emission spectrum analysis is feasible.

17.
Hepatogastroenterology ; 58(106): 682-6, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21661452

RESUMO

BACKGROUND/AIMS: Since telomeres and telomerase play crucial roles in maintaining cell immortalization and cancer progression, they may be targets for anticancer treatment. PinX1 is a potent telomerase inhibitor, and a putative tumor suppressor. The use of PinX1 to treat cancers has not been reported yet. METHODOLOGY: In order to use PinX1 in gene therapy for gastric carcinoma, we transfected PinX1 gene into the gastric carcinoma line MKN28 using the eukaryotic expression vector pIRES2-EGFP. PinX1-expressing, drug-resistant clones were screened with G418 and used in the study. RESULTS: MKN28 cells transfected with PinX1 gene grew more slowly than the cells not transfected or transfected with void vectors (p<0.05). The IC50 value decreased markedly in cells transfected with PinX1 gene. PinX1 gene transfection enhanced the sensitivity of MKN28 cells to 5-fluorouracil (p<0.05). CONCLUSIONS: PinX1 may be used in gene therapy for gastric carcinoma.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Fluoruracila/farmacologia , Terapia Genética , Neoplasias Gástricas/terapia , Proteínas Supressoras de Tumor/genética , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Neoplasias Gástricas/patologia , Telomerase/fisiologia , Transfecção
18.
J Gastrointest Surg ; 14(8): 1227-34, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20544396

RESUMO

INTRODUCTION: The aim of this study was to investigate the role of Mad1/c-Myc in telomerase regulation in gastric cancer cells in order to gain insight into telomerase activity and to evaluate PinX1 as a putative inhibitor of gastric cancer. METHODS: PinX1 and PinX1siRNA eukaryotic expression vectors were constructed by recombinant technology and transfected into gastric carcinoma cells using Lipofectamine 2000. Telomerase activity was measured by the telomeric repeat amplification protocol. Apoptosis of gastric cancer cells was analyzed by flow cytometry and transmission electron microscopy. Reverse transcription-polymerase chain reaction and Western blotting were used to assess the expression levels of PinX1 and Mad1/c-Myc. RESULTS: We found that PinX1-negative gastric cancer cells showed significantly higher telomerase activity than did the PinX1-postive cells. PinX1-transfection reduced telomerase activity in PinX1-negative gastric cancer cells and exhibited an upregulation of Mad1 and downregulation of c-Myc expression. Pinx1 RNAi treatment led to downregulation of Mad1 and upregulation of c-Myc. CONCLUSION: Suppression of telomerase activity mediated by PinX1 is involved in the Mad1/c-Myc pathway.


Assuntos
Proteínas de Ciclo Celular/genética , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica , Proteínas Nucleares/genética , RNA Neoplásico/genética , Neoplasias Gástricas/genética , Telomerase/metabolismo , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor/genética , Apoptose , Western Blotting , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Citometria de Fluxo , Mucosa Gástrica/metabolismo , Mucosa Gástrica/ultraestrutura , Genes myc , Humanos , Microscopia Eletrônica de Transmissão , Proteínas Nucleares/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Telomerase/genética , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/metabolismo
19.
Mol Diagn Ther ; 14(3): 155-61, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20560677

RESUMO

OBJECTIVE: Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is thought to be a promising anti-neoplastic agent because of its ability to selectively induce apoptosis in cancer cells. However, some cancer cells are resistant to TRAIL. The mechanisms underlying this resistance are unclear. The aim of this study was to explore the role of programmed cell death 4 (PDCD4) in regulating TRAIL sensitivity in gastric cancer cells. METHODS: PDCD4 complementary DNA and PDCD4-specific short-hairpin RNA (shRNA) fragments were transfected into TRAIL-sensitive and -resistant gastric cancer cells. Expression of PDCD4 and Akt was detected via western blot. Cell survival and apoptosis were measured using 3-(4,5-dimethylthiazolyl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometry (FCM) assays. RESULTS: We found that upregulation of PDCD4 enhanced TRAIL sensitivity in gastric cancer cells. Downregulation of PDCD4 decreased TRAIL sensitivity. Inhibition of Akt by the phosphoinositide 3-kinase (PI3K) inhibitor LY294002 induced PDCD4 activity and enhanced TRAIL sensitivity in TRAIL-resistant gastric cancer cells. CONCLUSION: We demonstrated that PDCD4 regulates TRAIL sensitivity in gastric cancer cells by inhibiting the PI3K/Akt signaling pathway.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Apoptose/efeitos dos fármacos , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas de Ligação a RNA/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Técnicas de Silenciamento de Genes , Humanos , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/metabolismo , Neoplasias Gástricas/enzimologia , Neoplasias Gástricas/patologia , Regulação para Cima/efeitos dos fármacos
20.
Hepatogastroenterology ; 56(94-95): 1371-6, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19950794

RESUMO

BACKGROUND/AIMS: To analyze the differential expression genes (DEGs) between esophageal adenocarcinoma (EAC) and para-cancerous tissue (PCT) and explore the target genes related to the development and progression of EAC. METHODOLOGY: The total RNAs of matched EAC and para-cancerous tissue of EAC patients were isolated using one step Trizol method. Matched RNAs were qualified using 10 g/L agarose gel electrophoresis. cRNAs were synthesized, fluorescence labeled and purified after total RNAs were purified. The RNAs of EAC and PCT were hybridized with Agilent oligomicroarray (30,968 probes). The fluorescence intensity features were detected by Agilent scanner and quantified by feature extraction software. RESULTS: (1)The total RNA, reverse transcription product and fluorescence labeled cRNA were all of high quality; (2)There were 212 up-regulated genes and 126 down-regulated genes am- ong 2-fold DEGs, including 16 genes related to cytochrome P450 (CYP). CONCLUSIONS: Many EAC-assoeiated genes were screened by the high-throughput gene chip method. The development and progression of EAC is a complicated process involving multigenes and multiprocedures. The down-regulated expression of CYP related genes and gene polymorphism of CYP2 subfamily may be involved in the onset and progress of EAC.


Assuntos
Adenocarcinoma/enzimologia , Neoplasias Esofágicas/enzimologia , Adenocarcinoma/etiologia , Sistema Enzimático do Citocromo P-450/genética , Regulação para Baixo , Neoplasias Esofágicas/etiologia , Perfilação da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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