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1.
Virus Res ; 338: 199234, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37802295

RESUMEN

Dengue virus (DENV) is one of the most prevalent arthropod-borne diseases. It may cause dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS), while no effective vaccines and drugs are available. Our study demonstrated that conessine exhibits broad antiviral activity against several enveloped viruses, including DENV, vesicular stomatitis virus, and herpes simplex virus. In addition, conessine has no direct destructive effect on the integrity or infectivity of virions. Both pre-treatment and post-treatment with conessine significantly reduce DENV replication. Pre-treatment with conessine disrupts the endocytosis of enveloped viruses, while post-treatment disturbs DENV RNA replication or translation at an early stage. Through screening differentially expressed genes by transcriptome sequencing, we found that conessine may affect cholesterol biosynthesis, metabolism or homeostasis. Finally, we confirmed that conessine inhibits virus replication through up-regulating cholesterol levels. Our work suggests that conessine could be developed as a prophylactic and therapeutic treatment for infectious diseases caused by enveloped viruses.


Asunto(s)
Virus del Dengue , Dengue , Humanos , Virus del Dengue/fisiología , Colesterol/farmacología , Replicación Viral , Antivirales/farmacología , Antivirales/uso terapéutico
2.
Front Bioeng Biotechnol ; 11: 1207048, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37362207

RESUMEN

Introduction: Drosophila melanogaster is a model organism for studying developmental biology and human neural disorders. Nanobodies are the variable domains of the heavy chains of camelid heavy-chain antibodies (VHHs) with high affinity to their antigens and have applications in basic research, similar to traditional antibodies. In addition, nanobodies acting as functionalized antibodies or protein binders have become an additional valuable approach in Drosophila. This study aimed to develop a VHH library against Drosophila proteins and confirm its availability by retrieving some Drosophila protein-specific nanobodies from the library. Methods: An alpaca was first immunized with Drosophila embryo lysate and then its lymphocytes were isolated. Total RNA was extracted and cDNA was synthesized. The vhh sequences were amplified by two round PCR, which were then ligated to a phage display vector pADL-10b. The ligation products were transduced into SS320 competent cells to generate a VHH library. From this library, nanobodies against CG7544, Myc, and CyclinE was enriched and screened by phage display technology and ELISA. DNA sequences of identified nanobodies were cloned into pADL-10b-Flag-His for expression and purification in Escherichia coli SS320. Binding ability of purified nanobodies with corresponding antigens were determined by ELISA and surface plasmon resonance in vitro. Results: In this study, an immune VHH library against Drosophila embryo proteins was generated with a capacity of 3 × 107. From this library, eight nanobodies against three Drosophila proteins, Myc, CyclinE, and CG7544, were identified and the DNA sequences of these nanobodies were obtained. These nanobodies were successfully expressed and purified from Escherichia coli SS320, and were demonstrated to bind corresponding antigens with high affinity in vitro. Moreover, the equilibrium constant between the highest enriched nanobodies and corresponding antigens were calculated. Conclusion: In summary, we report the availability of an immune VHH library and a highly efficient panning strategy for nanobodies against proteins in Drosophila.

3.
Genet Test Mol Biomarkers ; 24(4): 188-194, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32216635

RESUMEN

Aims: Cervical cancer is the second most common cause of cancer-related deaths in developing nations. Human papillomavirus prophylactic vaccines are not widely available, and there are shortages of gynecologists and cytologists in the already overburdened health care systems. The aim of this study was to identify circulating microRNAs (miRNAs) that could be used as feasible screening tests for cervical cancer in low-resource regions. Materials and Methods: Serum expression levels of five miRNAs were measured and validated by quantitative real-time polymerase chain reaction in cervical squamous cell carcinoma (CSCC) patients, cervical intraepithelial neoplasia patients, and healthy individuals. Squamous cell carcinoma-related antigen (SCC-Ag) was also measured in the serum. Results: Serum miR-638, miR-203a-3p, miR-1914-5p, and miR-521 levels were downregulated in the CSCC group (p < 0.05). Receiver operating characteristic (ROC) curve analysis indicated that the area under the ROC curve (AUC) values for miR-638 and miR-521 were 0.734 and 0.742, respectively, for discriminating CSCC patients from healthy controls. Furthermore, the combined use of miR-638 and SCC-Ag yielded the best screening performance and increased the AUC value, sensitivity, and specificity to 0.956, 94.87%, and 80.00%, respectively. Conclusion: This study suggested that miR-638 and miR-521 have independent screening value and that the combined measurement of miR-638 and SCC-Ag resulted in a better ability to discriminate patients with CSCC from healthy individuals.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/genética , MicroARNs/genética , Adulto , Antígenos de Neoplasias/sangre , Antígenos de Neoplasias/metabolismo , Biomarcadores de Tumor/sangre , Carcinoma de Células Escamosas/sangre , China , Femenino , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica/genética , Humanos , MicroARNs/metabolismo , Persona de Mediana Edad , Curva ROC , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Serpinas/sangre , Serpinas/metabolismo , Neoplasias del Cuello Uterino/sangre , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/genética
4.
Toxicol In Vitro ; 62: 104698, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31669364

RESUMEN

Both PM2.5 and respiratory viruses are part of the atmospheric constituents. Respiratory viruses are often associated with PM2.5 exposure, but the mechanism of toxicity remains to be explored. The vitro models that adequately reproduce healthy cells or diseased cells exposing to PM2.5 and infecting VSV can provide a useful tool for studying innate immune mechanisms and investigating new therapeutic focus. In the environment of PM2.5, an infection model in which VSV infected A549 cells was established, that mimics the state in which the antiviral innate immune pathways are activated after the respiratory system is infected with RNA viruses. Subsequently, the model was exposed to PM2.5 for 24 h. PM2.5 could be ingested by A549 cells and synergize with VSV to inhibit cell viability and promote apoptosis. The expression of VSV-G were more abundant after VSV-infected A549 cells were exposed to PM2.5. Furthermore, PM2.5 inhibits VSV-induced IFN-ß expression in A549 cells. ISG15, CCL-5, and CXCL-10 had the same expression tendency with IFN-ß mRNA, consistently. Interestingly, when MG132 was applied, the expression of p-IRF-3 and IFN-ß proteins reduced by PM2.5 were refreshed. Conversely, the expression of VSV-G proteins were decreased. PM2.5 could degrade p-IRF-3 proteins by ubiquitination pathway to inhibit VSV-induced IFN-ß expression in A549 cells. Therefore, replication of the VSV viruses was promoted.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Factor 3 Regulador del Interferón/metabolismo , Material Particulado/toxicidad , Ubiquitinación/efectos de los fármacos , Vesiculovirus/efectos de los fármacos , Células A549 , Apoptosis/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Factor 3 Regulador del Interferón/efectos de los fármacos , Interferón beta/metabolismo , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Estomatitis Vesicular/prevención & control , Estomatitis Vesicular/virología
5.
Front Genet ; 10: 1123, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31803230

RESUMEN

A case-control study was used to explore the association between the methylation status in the promoter regions of the cGAS, MAVS, and TRAF3 genes and the diseases of cervical precancerous lesions (CPL) and cervical cancer (CC) in a Southern Chinese population, and to further explore their interaction effects with high-risk human papillomavirus (hrHPV) infection and environmental factors in these diseases. The study protocol was approved by the ethics committee of The First Affiliated Hospital of Jinan University, and this study was performed in 97 healthy controls, 75 patients with CPL and 33 patients with CC, while each participant has read and signed the informed consent forms before enrolment. The promoter methylation status genes were detected from the bisulfite-treated DNA by the bisulfite sequencing PCR (BSP) technique, which was carried out using MethPrimer. The cGAS, MAVS, and TRAF3 promoter methylation levels in CPL (CPL cGAS = 35.40%, CPL MAVS = 24.26%, and CPL TRAF3 = 96.76%) were significantly higher than those in the control (Control cGAS = 31.87%, Control MAVS = 21.16%, and Control TRAF3 = 96.26%, PcGAS < 0.001, PMAVS < 0.001, and PTRAF3 = 0.001); however, there was no significant differences between the CC and control. In the logistic regression model with adjusted covariates, compared with the individuals whose cGAS methylation levels were less than or equal to 31.87%, the women with the levels more than 31.87% increased the risk of CPL by 2.49 times (ORa = 2.49, 95% CI = 1.31-4.75, P a = 0.006). The women with MAVS methylation levels above 21.16% were 1.97 times more likely to have CPL than the those with the levels less than 21.16% (ORa = 1.97, 95% CI = 1.06-3.69, P a = 0.033). A synergistic interaction was found between hrHPV and gene promoter methylation levels of cGAS and MAVS in CPL; however, no potential interaction was observed in CC. The promoter methylation levels in cGAS, MAVS, and TRAF3 genes are higher in CPL than in control, indicating that hypermethylation might be an early event in the progression of cervical intraepithelial neoplasia (CIN). The interaction between the promoter methylation levels in cGAS and MAVS genes and hrHPV infection might play a role in the development of CPL.

7.
Artículo en Inglés | MEDLINE | ID: mdl-31354628

RESUMEN

Objective: To evaluate the potential association between the genetic variants in miRNA processing genes (RAN, XPO5, DICER1, and TARBP2) and susceptibility to type 2 diabetes mellitus (T2DM) and its vascular complications, as well as to further investigate their interaction with environmental factors in type 2 diabetes. Methods: We conducted a case-control study in genotyping of five polymorphic loci, including RAN rs14035, XPO5 rs11077, DICER1 rs13078, DICER1 rs3742330, and TARBP2 rs784567, in miRNA processing genes to explore the risk factors for T2DM and diabetic vascular complications. Haplotype analyses, interactions of gene-gene and interactions of gene-environment were performed too. Results: We identified a 36% decreased risk of developing T2DM in individuals with the minor A allele in DICER1 rs13078 (OR: 0.64; 95%CI: 0.42-0.95; P: 0.026). The AA haplotype in DICER1 was also associated with a protective effect on T2DM compared with the AT haplotype (OR: 0.63; 95%CI: 0.42-0.94; P-value: 0.023). T2DM patients with the TT+TC genotype at RAN rs14035 had a 1.89-fold higher risk of developing macrovascular complications than patients with the CC genotype (OR: 1.89; 95%CI: 1.04-3.45; P-value: 0.037). We also identified two three-factor interaction models. One is a three-factor [DICER1 rs13078, body mass index (BMI), and triglyceride (TG)] interaction model for T2DM (OR: 5.93; 95%CI: 1.25-28.26; P = 0.025). Another three-factor [RAN rs14035, hypertension (HP), and duration of T2DM (DOD)] interaction model was found for macrovascular complications of T2DM (OR = 41.60, 95%CI = 11.75-147.35, P < 0.001). Conclusion: Our study provides new evidence that two single nucleotide polymorphisms (SNPs) of the miRNA processing genes, DICER1 and RAN, and their interactions with certain environmental factors might contribute to the risk of T2DM and its vascular complications in the southern Chinese population.

8.
Acta Trop ; 195: 35-43, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31004564

RESUMEN

Toxoplasma gondii has evolved many successful strategies for immune evasion. However, the parasite-derived effectors involved in modulating NF-κB signalling pathway are largely unknown. T. gondii Cathepsin C1 (CPC1) is widely conserved among T. gondii strains and is important for T. gondii intracellular growth and proliferation. Our study showed that CPC1 protein could abrogate NF-κB activation after screening dense granule proteins. CPC1 suppressed NF-κB activation at or downstream of p65 and decreased the production of IL-1, IL-8, IL-6, IL-12, and TNF-α. Western blot analysis revealed that CPC1 inhibited phospho-p65 and CPC1 proteins primarily settled in cytoplasm. RNA sequencing analysis revealed that overexpression of CPC1 significantly upregulated erythropoietin (EPO), which can be induced by the hypoxia-inducible factor -1α (HIF-1α) during hypoxia. Furthermore, dual-luciferase reporter assays confirmed that CPC1 upregulated HIF-1α. Finally, both the knockdown of EPO and restriction of HIF-1α partially eliminated the suppression impact of CPC1 on the NF-κB signalling pathway. Our study identified a previously unrecognized role of CPC1 in the negative regulation of NF-κB activation through positive regulation of the HIF-1α/EPO axis. For the first time, CPC1 was shown to play an important role in immune evasion during T. gondii infection.


Asunto(s)
Catepsina C/fisiología , Eritropoyetina/fisiología , Subunidad alfa del Factor 1 Inducible por Hipoxia/fisiología , FN-kappa B/fisiología , Toxoplasma/inmunología , Células HEK293 , Humanos , Evasión Inmune , Transducción de Señal/fisiología , Toxoplasma/enzimología
9.
Immunopharmacol Immunotoxicol ; 41(2): 199-206, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30724633

RESUMEN

Objective: The industrial production and combustion of coal can produce silica nanoparticles (nano-SiO2). It enters the human body mainly through the respiratory tract and exerts a toxic effect. However, whether nano-SiO2 can increase the IL-1ß-induced inflammatory expression in A549 cells has not been tested. Therefore, the synergistic toxicity of nano-SiO2 and IL-1ß to A549 was observed in our study. Materials and methods: We exposed A549 cells to nano-SiO2 (0, 100, 500, and 1000 µg/ml) for 12 and 24 h. The effect of nano-SiO2 on the viability of A549 cells was observed by the CCK-8 method. The A549 cells were exposed to nano-SiO2 (1 mg/mL) and cytokine IL-1ß (10 ng/mL) for 4 h, and we detected the expression of IL-1ß and IL-6 cytokines by real time quantitative polymerase chain (RT-qPCR) and enzyme linked immunosorbent assay (ELISA). The expression of ß-Actin, I-κB, phospho-ERK1/2 (P-ERK1/2), total-ERK1/2 (T-ERK1/2), phospho-JNK (P-JNK), total-JNK (T-JNK), phospho-P38 (P-P38), and total-P38 (T-P38) in A549 cells was detected by the Western Blot method. Results: The nano-SiO2 treatment resulted in a time-dependent decrease in the viability of A549 cells. The synergistic effect of nano-SiO2 and IL-1ß was observed on the new production of IL-1ß and IL-6 in A549 cells. The Western blot results showed that nano-SiO2 can increase the expression of IL-1ß and IL-6 by promoting the phosphorylation of ERK1/2 and elevating the phosphorylation of I-κB by IL-1ß. IL-1ß and IL-6 were induced by nano-SiO2, and the IL-1ß treatment with 20 µM of I-κBα phosphorylation inhibitor (PD98059) and 20 µM of ERK1/2 inhibitor (BAY11-7082) for 1 h was significantly lower than that of the control group in A549 cells. Discussion and conclusion: These results indicated that nano-SiO2 had a toxic effect on A549 cells, and this effect could increase IL-1ß on the A549 cell-induced inflammatory response. The results suggested that the release of IL-1ß and IL-6 in A549 was enhanced by the synergistic IL-1ß-induced phosphorylation of ERK1/2 and I-κB. This process is similar to a snowball, and it is possible that IL-1ß is continuously produced and repeatedly superimposed in A549 cells to produce an inflammatory effect; then, a vicious circle occurs, and an inflammatory storm is accelerated.


Asunto(s)
Interleucina-1beta/toxicidad , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Nanopartículas/efectos adversos , Dióxido de Silicio/toxicidad , Células A549 , Humanos , Inflamación/inducido químicamente , Inflamación/inmunología , Inflamación/patología , Interleucina-1beta/inmunología , Interleucina-6/inmunología , Sistema de Señalización de MAP Quinasas/inmunología , Proteína Quinasa 1 Activada por Mitógenos/inmunología , Proteína Quinasa 3 Activada por Mitógenos/inmunología , Factores de Tiempo
10.
J Basic Microbiol ; 59(3): 267-276, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30589093

RESUMEN

Marine Streptomyces sp. CC0208 isolated from the Bohai Bay showed high efficiency of cellulose degradation under optimized fermentation parameters. Also, as one of the bioinformatics-based approaches for the discovery of novel natural product and enzyme effectively, genome mining has been developed and applied widely. Herein, we reported the complete genome sequence of Streptomyces sp. CC0208.Whole-genome sequencing analysis revealed a genome size of 9,325,981 bp with a linear chromosome, GC content of 70.59% and 8487 protein-coding genes. Abundant genes have predicted functions in antibiotic metabolism and enzymes. A 20 enzymes closely associated with cellulose degradation were discovered. A total of 25 biosynthetic gene clusters (BGCs) of secondary metabolites were identified, including diverse classes of natural products. The availability of genome sequence of Streptomyces sp. CC0208 not only will assist in cracking the mechanism of cellulose degradation but also will provide the insights into the significant secondary metabolic potentials for the production of diverse compound classes based on rational strategies.


Asunto(s)
Celulosa/metabolismo , Genoma Bacteriano/genética , Metabolismo Secundario/genética , Streptomyces/genética , Streptomyces/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Productos Biológicos/metabolismo , Anotación de Secuencia Molecular , Familia de Multigenes , Filogenia , Agua de Mar/microbiología , Análisis de Secuencia de ADN , Streptomyces/clasificación
11.
Artículo en Inglés | MEDLINE | ID: mdl-30555415

RESUMEN

Objective: To explore the association between the methylation levels in the promoter regions of the NLRP3, AIM2, and ASC genes and T2DM and its vascular complications in a Southern Han Chinese population and further analyze their interaction and mediating effects with environmental factors in T2DM. Methods: A case-control study was used to determine the association between population characteristics, the methylation level in the promoter region of the NLRP3, AIM2, and ASC genes and T2DM and vascular complications. A mediating effect among genes-environment-T2DM and the interaction of gene-gene or gene-environment factors was explored. Results: In the logistic regression model with adjusted covariants, healthy people with lower total methylation levels in the AIM2 promoter region exhibited a 2.29-fold [OR: 2.29 (1.28~6.66), P = 0.011] increased risk of developing T2DM compared with higher-methylation individuals. T2DM patients without any vascular complications who had lower methylation levels (

12.
Artículo en Inglés | MEDLINE | ID: mdl-30319545

RESUMEN

Introduction: Published data regarding the association between solute carrier family 30, member 8 (SLC30A8) rs13266634 polymorphism and type 2 diabetes mellitus (T2DM) and impaired glucose regulation (IGR) risks in Chinese population are in-consistent. The purpose of this meta-analysis was to evaluate the association between SLC30A8 rs13266634 and T2DM/IGR in a Chinese population. Material and Methods: Three English (PubMed, Embase, and Web of Science) and three Chinese databases (Wanfang, CNKI, and CBMD database) were used for searching articles from January 2005 to January 2018. Odds ratio (OR) and 95% confidence interval (95%CI) were calculated with the random-effect model. Trial sequential analysis was also utilized. Results: Twenty-eight case-control studies with 25,912 cases and 26,975 controls were included for SLC30A8 and T2DM. Pooled risk allele C frequency for rs13266634 was 60.6% (95%CI: 59.2-62.0%) in the T2DM group and 54.8% (95%CI: 53.2-56.4%) in the control group which had estimated OR of 1.23 (95%CI: 1.17-1.28). Individuals who carried major homozygous CC and heterozygous CT genotype were at 1.51 and 1.23 times higher risk of T2DM, respectively, than those carrying minor homozygous TT. The most appropriate genetic analysis model was the co-dominant model based on comparison of OR1, OR2 and OR3. Five articles that involved 4,627 cases and 6,166 controls were included for SLC30A8 and IGR. However, no association was found between SLC30A8 rs13266634 and IGR (C vs. T, OR = 1.13, 95%CI: 0.98-1.30, p = 0.082). TSA revealed that the pooled sample sizes of T2DM exceeded the estimated required information size but not the IGR. Conclusion: The present meta-analysis demonstrated that SLC30A8 rs13266634 was a potential risk factor for T2DM, and more studies should be performed to confirm the association between rs13266634 polymorphism and IGR.

13.
J Proteomics ; 171: 73-80, 2018 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-28344024

RESUMEN

The morphology of Spirulina during cultivation is susceptible to external interferences, but the morphogenesis mechanism is still unclear. Here the proteomic changes of linear Spirulina and spiral Spirulina were comparatively investigated via isobaric tag for relative and absolute quantitation (iTRAQ). Totally 165 and 167 differences in proteins expression were screened out from the TJSD2/TJSD3 and TJBC4-1/TJBC4-2 groups, respectively. Gene ontology and metabolic pathway analysis of differences in proteins expression uncovered the metabolic pathways (photosynthesis, carbon fixation, sugar metabolism) that were significantly enriched with the proteins correlated with Spirulina morphogenesis. The results of differences in proteins expression in metabolic pathway were verified by quantitative real-time PCR. We also built a putative model of Spirulina morphogenesis mechanism and thought multiple metabolic pathways interact and take part in Spirulina morphogenesis.


Asunto(s)
Proteínas Bacterianas/metabolismo , Proteoma/metabolismo , Spirulina/metabolismo , Proteínas Bacterianas/genética , Metabolismo Energético , Ontología de Genes , Redes y Vías Metabólicas , Modelos Biológicos , Proteoma/genética , Spirulina/crecimiento & desarrollo
14.
Wei Sheng Wu Xue Bao ; 56(2): 232-40, 2016 Feb 04.
Artículo en Chino | MEDLINE | ID: mdl-27373071

RESUMEN

OBJECTIVE: Based on 16S rRNA and rpoC1 gene sequences, the phylogenetic relationship between Spirulina and Arthrospira were studied and compared. METHODS: We amplified, sequenced and analyzed 16S rRNA and rpoC1 of 84 strains. Then the phylogenetic trees were constructed and compared. RESULTS: The conserved sites percentage, average G+C content and sequence identity of rpoC1 were 49.7%, 47.7%, 76%-100% respectively, significantly lower than 79.4%, 55.6% and 91%-100% of 16S rRNA, and the heterogeneity degree was higher. The trees generated with two different genes showed similar topologies and thus inferred consistent phylogenetic relationships. Eighty-four experimental strains were divided into 3 groups belonging to 2 genera: F-35 1, F-904-2, F-1070 and TJBC14 were Spirulina and the rest were Arthrospira. Although morphospecies and geographical species could not be distinguished based on 16S rRNA and rpoC1 gene sequences, the bootstrap value of rpoC1 (100%) was higher than that of 16S rRNA (99%). Moreover, clustering effect of rpoC1 for Spirulina and Arthrospirai was better than 16S rRNA. CONCLUSION: Spirulina and Arthrospira were different genera, rpoC1 gene has more advantage to distinguish the strains in the same genus than that of 16S rRNA gene.


Asunto(s)
Proteínas Bacterianas/genética , Filogenia , ARN Ribosómico 16S/genética , Spirulina/genética , ADN Bacteriano/genética , ADN Ribosómico/genética , Spirulina/clasificación , Spirulina/aislamiento & purificación
15.
Mar Genomics ; 24 Pt 3: 197-8, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26001511

RESUMEN

The cyanobacteria TJSD091 strain, a member of the genus Arthrospira was isolated from seaside wetland in China, Bohai. The draft genome sequence of Arthrospira sp. TJSD091 with a genome size of approximately 6.3 Mbp and a G+C content of 44.75% is reported.


Asunto(s)
ADN Bacteriano/genética , Genoma Bacteriano/genética , Spirulina/genética , Datos de Secuencia Molecular , Spirulina/clasificación , Humedales
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(9): 2485-8, 2009 Sep.
Artículo en Chino | MEDLINE | ID: mdl-19950658

RESUMEN

Two kinds of Yb3+ doped silicate laser glass with little difference were produced by high temperature of melting process. The absorption and emission spectra of the two glass samples were tested by the correlative spectrographs; the integral absorption cross section, stimulated emission cross section, fluorescence line-width, fluorescence lifetime, least particle count, saturation pump intensity and least pump intensity of the Yb3+ -doped laser glasses were calculated respectively, and by comparison it was found that the chart of the absorption cross section is similar to the stimulated emission cross section calculated by the reciprocity method, and is very different from the stimulated emission cross section calculated by the Fuchbauer-Ladenburger method. This result is precisely in line with the theoretical analysis. The line-types of the absorption spectra of the two glass samples are almost the same, and the first peak value of absorption is located at 975 nm while the second peak value is at 908 nm. As the two components of the samples are not very different, the accord of the line-types of the absorption spectra indicates that the makeup of the glass material is the primary factor influencing the line-type of the absorption spectra. The fluorescence spectra of the two glass samples are very different, and the first fluorescence peak value of sample one is located at 993 nm with the second peak value at 1029 nm, while the first fluorescence peak value of sample two is located at 1 035 nm with the second peak value at 994 nm. The cause of the major difference in the fluorescence spectra of two samples lies in the different doping density of Yb3+. By comparison we found that the laser performance of sample two is better than that of sample one. The test shows that both samples are suitable for drawing fiber.

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