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1.
BMC Genomics ; 24(1): 613, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37828501

RESUMO

BACKGROUND: The domestic dog, Canis lupus familiaris, is a companion animal for humans as well as an animal model in cancer research due to similar spontaneous occurrence of cancers as humans. Despite the social and biological importance of dogs, the catalogue of genomic variations and transcripts for dogs is relatively incomplete. RESULTS: We developed CanISO, a new database to hold a large collection of transcriptome profiles and genomic variations for domestic dogs. CanISO provides 87,692 novel transcript isoforms and 60,992 known isoforms from whole transcriptome sequencing of canine tumors (N = 157) and their matched normal tissues (N = 64). CanISO also provides genomic variation information for 210,444 unique germline single nucleotide polymorphisms (SNPs) from the whole exome sequencing of 183 dogs, with a query system that searches gene- and transcript-level information as well as covered SNPs. Transcriptome profiles can be compared with corresponding human transcript isoforms at a tissue level, or between sample groups to identify tumor-specific gene expression and alternative splicing patterns. CONCLUSIONS: CanISO is expected to increase understanding of the dog genome and transcriptome, as well as its functional associations with humans, such as shared/distinct mechanisms of cancer. CanISO is publicly available at https://www.kobic.re.kr/caniso/ .


Assuntos
Neoplasias , Lobos , Cães , Animais , Humanos , Transcriptoma , Lobos/genética , Genoma , Genômica , Neoplasias/genética , Neoplasias/veterinária , Isoformas de Proteínas/genética
2.
BMC Bioinformatics ; 19(Suppl 1): 40, 2018 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-29504894

RESUMO

BACKGROUND: Aberrant mutations in KRAS play a critical role in tumor initiation and progression, and are a negative prognosis factor in lung adenocarcinoma (LUAD). RESULTS: Using genomic analysis for K-Ras isoforms (K-Ras4A and K-Ras4B) and large-scale multi-omics data, we inspected the overall survival (OS) and disease-free survival (DFS) of LUAD patients based on the abundance of transcript variants by analyzing RNA expression and somatic mutation data from The Cancer Genome Atlas (n = 516). The expression of the minor transcript K-Ras4A and its proportion were positively correlated with the presence of KRAS mutations in LUAD. We found that both K-Ras4A abundance measures (expression and proportion) have a strong association with poor OS (p = 0.0149 and p = 3.18E-3, respectively) and DFS (p = 3.03E-4 and p = 0.0237, respectively), but only in patients harboring KRAS mutations. A Cox regression analysis showed significant results in groups with low expression (hazard ratio (HR) = 2.533, 95% confidence interval (CI) = 1.380-4.651, p = 2.72E-3) and low proportion (HR = 2.549, 95% CI = 1.387-4.684, p = 2.58E-3) of K-Ras4A. CONCLUSIONS: Based on the above results, we report the possible use of abundance measures for K-Ras4A for predicting the survival of LUAD patients with KRAS mutations.


Assuntos
Adenocarcinoma de Pulmão/mortalidade , Neoplasias Pulmonares/mortalidade , Proteínas Proto-Oncogênicas p21(ras)/genética , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/terapia , Idoso , Intervalo Livre de Doença , Feminino , Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Mutação , Prognóstico , Modelos de Riscos Proporcionais , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
3.
BMC Genomics ; 17(1): 631, 2016 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-27519173

RESUMO

BACKGROUND: Alternative splicing events that result in the production of multiple gene isoforms reveals important molecular mechanisms. Gene isoforms are often differentially expressed across organs and tissues, developmental stages, and disease conditions. Specifically, recent studies show that aberrant regulation of alternative splicing frequently occurs in cancer to affect tumor cell transformation and growth. While analysis of isoform expression is important for discovering tumor-specific isoform signatures and interpreting relevant genomic mutations, there is currently no web-based, easy-to-use, and publicly available platform for this purpose. DESCRIPTION: We developed ISOexpresso to provide information regarding isoform existence and expression, which can be grouped by cancer vs. normal conditions, cancer types, and tissue types. ISOexpresso implements two main functions: First, the Isoform Expression View function creates visualizations for condition-specific RNA/isoform expression patterns upon query of a gene of interest. With this function, users can easily determine the major isoform (the most expressed isoform in a sample) of a gene with respect to the condition and check whether it matches the known canonical isoform. ISOexpresso outputs expression levels of all known transcripts to check alterations of expression landscape and to find potential tumor-specific isoforms. Second, the User Data Annotation function supports annotation of genomic variants to determine the most plausible consequence of a variation (e.g., an amino acid change) among many possible interpretations. As most coding sequence mutations are effective through the subsequent transcription and translation, ISOexpresso automatically prioritizes transcripts that act as backbones for mutation effect prediction by their relative expression. By employing ISOexpresso, we could investigate the consistency between the most expressed and known canonical/principal isoforms, as well as infer candidate tumor-specific isoforms based on their expression levels. In addition, we confirmed that ISOexpresso could easily reproduce previously known isoform expression patterns: recurrent observation of a major isoform across tissues, differential isoform expression patterns in a given tissue, and switching of major isoform during tumorigenesis. CONCLUSIONS: ISOexpresso serves as a web-based, easy-to-use platform for isoform expression and alteration analysis based on large-scale cancer database. We anticipate that ISOexpresso will expedite formulation and confirmation of novel hypotheses by providing isoform-level perspectives on cancer research. The ISOexpresso database is available online at http://wiki.tgilab.org/ISOexpresso/ .


Assuntos
Perfilação da Expressão Gênica/instrumentação , Regulação Neoplásica da Expressão Gênica , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Interface Usuário-Computador , Bases de Dados Factuais , Proteína Forkhead Box M1/genética , Proteína Forkhead Box M1/metabolismo , Humanos , Internet , Mutação , Proteínas de Neoplasias/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
4.
Int J Legal Med ; 128(1): 51-2, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23525666

RESUMO

This study reports on the forensic parameters of 30 insertion-deletion polymorphisms (Indels) (Investigator DIPplex® kit) in 100 individuals from a Korean population. The match probability ranged from 0.353 to 0.789, and the combined power of discrimination reached 0.99999999995. The DIPplex® kit is more discriminative in Koreans than six COfiler® short tandem repeats (STRs), but less discriminative than nine Profiler Plus® STRs. This study further demonstrated that some Indels in the DIPplex® kit could be used as Asian ancestry informative markers through a comparison with other population data.


Assuntos
Povo Asiático/genética , Marcadores Genéticos/genética , Genética Populacional , Genótipo , Mutação INDEL/genética , Efeito Fundador , Frequência do Gene , Triagem de Portadores Genéticos , Loci Gênicos/genética , Humanos , Repetições de Microssatélites/genética , Reação em Cadeia da Polimerase , Probabilidade , República da Coreia
5.
Adv Mater ; 36(3): e2308819, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37832157

RESUMO

The combined effects of compact TiO2 (c-TiO2 ) electron-transport layer (ETL) are investigated without and with mesoscopic TiO2 (m-TiO2 ) on top, and without and with an iodine-terminated silane self-assembled monolayer (SAM), on the mechanical behavior, opto-electronic properties, photovoltaic (PV) performance, and operational-stability of solar cells based on metal-halide perovskites (MHPs). The interfacial toughness increases almost threefold in going from c-TiO2 without SAM to m-TiO2 with SAM. This is attributed to the synergistic effect of the m-TiO2 /MHP nanocomposite at the interface and the enhanced adhesion afforded by the iodine-terminated silane SAM. The combination of m-TiO2 and SAM also offers a significant beneficial effect on the photocarriers extraction at the ETL/MHP interface, resulting in perovskite solar cells (PSCs) with power-conversion efficiency (PCE) of over 24% and 20% for 0.1 and 1 cm2 active areas, respectively. These PSCs also have exceptionally long operational-stability lives: extrapolated T80 (duration at 80% initial PCE retained) is ≈18 000 and 10 000 h for 0.1 and 1 cm2 active areas, respectively. Postmortem characterization and analyses of the operational-stability-tested PSCs are performed to elucidate the possible mechanisms responsible for the long operational-stability.

6.
Artigo em Inglês | MEDLINE | ID: mdl-36752619

RESUMO

Novel TiO2 nanorods (NRs) with various lengths of 70-200 nm and uniform widths of 46-48 nm are selectively synthesized by a solvothermal reaction under a basic environment. The length of TiO2 NRs is reproducibly tuned by varying the concentration of tetramethylammonium hydroxide (TMAH), while the NRs in the pure anatase phase are grown in the [001] direction, caused by the preferential binding affinity of TMAH to the TiO2 (101) facet. TiO2 NRs of various lengths are then applied to form the electron transporting layer (ETL) of mesoscopic perovskite solar cells (PSCs). We found that PSC devices with NRs exhibit superior photovoltaic (PV) performance to those with conventional 46 nm-sized TiO2 nanoparticles (NP46). Particularly, the PSC with TiO2 NRs of 110 nm length (NR110) exhibits the optimum PV conversion efficiency (PCE): the average PCE is 22.64% with a VOC of 1.137 V, a JSC of 24.60 mA·cm-2, and a FF of 80.96%, while the champion PCE is 23.18%. In addition, the PSC with NR110 (PSC-NR110) reveals significantly improved long-term stability in air with a relative humidity of 40-50%. In 1000 h, its PCE is reduced by only 9% whereas that of PSC with NP46 decreases by 25%. The PSC properties analyzed by impedance spectroscopy and J-V curve measurements under dark conditions and at various light intensities provide evidence that PSC-NR110 has fewer defects and shows significantly reduced charge recombination. We discuss the advantages of NR structures in preparing the ETL of PSC devices and also explain why the charge recombination is suppressed.

7.
Nanomaterials (Basel) ; 12(22)2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36432255

RESUMO

Li-doped CuSCN films of various compositions were applied as hole-transporting material (HTM) for mesoscopic perovskite solar cells (PSCs). Those films of ~60 nm thickness, spin-coated on the perovskite layer, exhibit significantly higher crystallinity and hole mobility compared with the pristine CuSCN films. Among them, 0.33% Li-doped CuSCN (Li0.33:CuSCN) shows the best performance as the HTM of mesoscopic PSC. Furthermore, by depositing a slight amount of PCPDTBT over the Li0.33:CuSCN layer, the VOC was increased to 1.075 V, resulting in an average PCE of 20.24% and 20.65% for the champion device. These PCE and VOC values are comparable to those of PSC using spiro-OMETAD (PCE: 20.61%, VOC: 1.089 V). Such a remarkable increase can be attributed to the penetration of the PCPDTBT polymer into the grain boundaries of the Li0.33:CuSCN film, and to the interface with the perovskite layer, leading to the removal of defects on the perovskite surface by paving the non-contacting parts, as well as to the tight interconnection of the Li0.33:CuSCN grains. The PSC device with Li0.33:CuSCN showed a high long-term stability similar to that with bare CuSCN, and the introduction of PCPDTBT onto the perovskite/Li0.33:CuSCN further improved device stability, exhibiting 94% of the initial PCE after 100 days.

8.
Sci Data ; 9(1): 132, 2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-35361774

RESUMO

The identification of efficient and sensitive biomarkers for non-invasive tests is one of the major challenges in cancer diagnosis. To address this challenge, metabolomics is widely applied for identifying biomarkers that detect abnormal changes in cancer patients. Canine mammary tumors exhibit physiological characteristics identical to those in human breast cancer and serve as a useful animal model to conduct breast cancer research. Here, we aimed to provide a reliable large-scale metabolite dataset collected from dogs with mammary tumors, using proton nuclear magnetic resonance spectroscopy. We identified 55 metabolites in urine samples from 20 benign, 87 malignant, and 49 healthy control subjects. This dataset provides details of mammary tumor-specific metabolites in dogs and insights into cancer-specific metabolic alterations that share similar molecular characteristics.


Assuntos
Cães , Neoplasias Mamárias Animais , Animais , Feminino , Neoplasias Mamárias Animais/urina , Metabolômica , Espectroscopia de Prótons por Ressonância Magnética
10.
Int J Legal Med ; 125(6): 841-8, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21184092

RESUMO

Complete mitochondrial control region data were generated for 230 unrelated Pathans from North West Frontier Province and Federally Administered Tribal Areas of Pakistan. To confirm data quality and to explore the genetic structure of Pathans, mitochondrial DNA haplogroup affiliation was determined by shared haplogroup-specific polymorphisms in the control region and by the analysis of diagnostic coding region single-nucleotide polymorphisms using a multiplex system for the assignment of eight haplogroups: M, N1'5, W, R, R0, T, J, and U. Sequence comparison revealed that 193 haplotypes were defined by 215 variable sites when major insertions were ignored at nucleotide positions 16193, 309, and 573. From a phylogenetic perspective, Pathans have a heterogeneous origin, displaying a high percentage of West Eurasian haplogroups followed by haplogroups native to South Asia and a small fraction from East Asian lineages. In population comparisons, this ethnic group differed significantly from several other ethnic groups from Pakistan and surrounding countries. These results suggest that frequency estimates for mtDNA haplotypes should be determined for endogamous ethnic groups individually instead of pooling data for these subpopulations into a single dataset for the Pakistani population. Data presented here may contribute to the accuracy of forensic mtDNA comparisons in the Pathans of Pakistan.


Assuntos
DNA Mitocondrial/análise , Etnicidade/genética , Genética Populacional , Genética Forense , Haplótipos , Humanos , Masculino , Paquistão/etnologia , Polimorfismo de Nucleotídeo Único
11.
Nucleic Acids Res ; 37(Database issue): D423-30, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19015128

RESUMO

Influenza epidemics arise through the acquisition of viral genetic changes to overcome immunity from previous infections. An increasing number of complete genomes of influenza viruses have been sequenced in Asia in recent years. Knowledge about the genomes of the seasonal influenza viruses from different countries in Asia is valuable for monitoring and understanding of the emergence, migration and evolution of strains. In order to make full use of the wealth of information from such data, we have developed an integrated user friendly relational database, Influenza Sequence and Epitope Database (ISED), that catalogs the influenza sequence and epitope information obtained in Asia. ISED currently hosts a total of 13,020 influenza A and 2984 influenza B virus sequence data collected in 17 countries including 9 Asian countries, and a total of approximately 545 amantadine-resistant influenza virus sequences collected in Korea. ISED provides users with prebuilt application tools to analyze sequence alignment and different patterns and allows users to visualize epitope-matching structures, which is freely accessible at http://influenza.korea.ac.kr and http://influenza.cdc.go.kr.


Assuntos
Alphainfluenzavirus/genética , Alphainfluenzavirus/imunologia , Antígenos Virais/química , Betainfluenzavirus/genética , Betainfluenzavirus/imunologia , Bases de Dados Genéticas , Epitopos/química , Genoma Viral , Análise de Sequência , Software , Proteínas Virais/química
12.
PLoS One ; 16(2): e0246354, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33600481

RESUMO

Short DNA oligonucleotides (~4 mer) have been used to index samples from different sources, such as in multiplex sequencing. Presently, longer oligonucleotides (8-12 mer) are being used as molecular barcodes with which to distinguish among raw DNA molecules in many high-tech sequence analyses, including low-frequent mutation detection, quantitative transcriptome analysis, and single-cell sequencing. Despite some advantages of using molecular barcodes with random sequences, such an approach, however, makes it impossible to know the exact sequences used in an experiment and can lead to inaccurate interpretation due to misclustering of barcodes arising from the occurrence of unexpected mutations in the barcodes. The present study introduces a tool developed for selecting an optimal barcode subset during molecular barcoding. The program considers five barcode factors: GC content, homopolymers, simple sequence repeats with repeated units of dinucleotides, Hamming distance, and complementarity between barcodes. To evaluate a selected barcode set, penalty scores for the factors are defined based on their distributions observed in random barcodes. The algorithm employed in the program comprises two steps: i) random generation of an initial set and ii) optimal barcode selection via iterative replacement. Users can execute the program by inputting barcode length and the number of barcodes to be generated. Furthermore, the program accepts a user's own values for other parameters, including penalty scores, for advanced use, allowing it to be applied in various conditions. In many test runs to obtain 100000 barcodes with lengths of 12 nucleotides, the program showed fast performance, efficient enough to generate optimal barcode sequences with merely the use of a desktop PC. We also showed that VFOS has comparable performance, flexibility in program running, consideration of simple sequence repeats, and fast computation time in comparison with other two tools (DNABarcodes and FreeBarcodes). Owing to the versatility and fast performance of the program, we expect that many researchers will opt to apply it for selecting optimal barcode sets during their experiments, including next-generation sequencing.


Assuntos
Código de Barras de DNA Taxonômico/métodos , Oligonucleotídeos/genética , Simulação por Computador , DNA/genética , Perfilação da Expressão Gênica/métodos , Modelos Estatísticos , Mutação/genética , Análise de Célula Única/métodos
13.
Biochem Biophys Res Commun ; 397(3): 429-35, 2010 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-20529698

RESUMO

The crystal structures of aprotinin and its complex with sucrose octasulfate (SOS), a polysulfated heparin analog, were determined at 1.7-2.6A resolutions. Aprotinin is monomeric in solution, which associates into a decamer at high salt concentrations. Sulfate ions serve to neutralize the basic amino acid residues of aprotinin to stabilize the decameric aprotinin. Whereas SOS interacts with heparin binding proteins at 1:1 molar ratio, SOS was surprisingly found to induce strong agglutination of aprotinins. Five molecules of aprotinin interact with one molecule of the sulfated sugar, which is stabilized by electrostatic interactions between the positively charged residues of aprotinin and sulfate groups of SOS. The multiple binding modes of SOS with five individual aprotinin molecules may represent the diverse patterns of potential heparin binding to aprotinin, reflecting the interactions of densely packed protein molecules along the heparin polymer.


Assuntos
Aprotinina/química , Heparina/química , Sacarose/análogos & derivados , Animais , Bovinos , Cristalização , Cristalografia por Raios X , Ligação Proteica , Conformação Proteica , Multimerização Proteica , Estabilidade Proteica , Sacarose/química
14.
J Clin Microbiol ; 48(6): 2177-85, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20392920

RESUMO

Influenza epidemics arise through the accumulation of viral genetic changes, culminating in a novel antigenic type that is able to escape host immunity. Following an outbreak of the A/Fujian/411/2002-like strains in Asia, including China, Japan, and South Korea, in 2002, Australia and New Zealand experienced substantial outbreaks of the same strains in 2003, and subsequently worldwide outbreaks occurred in the 2003-2004 season. The emergence of A/Fujian/411/2002-like strains coincided with a higher level of influenza-like illness in South Korea than what is seen at the peak of a normal season, and there was at least a year's difference between South Korea and the United States. Genetic evolution of human influenza A/H3N2 viruses was monitored by sequence analysis of hemagglutinin (HA) genes collected in Asia, including 269 (164 new) HA genes isolated in South Korea from 1999 to 2007. The Fujian-like influenza strains were disseminated with rapid sequence variation across the antigenic sites of the HA1 domain, which sharply distinguished between the A/Moscow/10/1999-like and A/Fujian/411/2002-like strains. This fast variation, equivalent to approximately 10 amino acid changes within a year, occurred in Asia and would be the main cause of the disappearance of the reassortants, although the reassortant and nonreassortant Fujian-like strains circulated simultaneously in Asia.


Assuntos
Evolução Molecular , Vírus da Influenza A Subtipo H3N2/genética , Influenza Humana/epidemiologia , Influenza Humana/virologia , Antígenos Virais/genética , Análise por Conglomerados , Variação Genética , Hemaglutininas Virais/genética , Humanos , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Modelos Moleculares , Dados de Sequência Molecular , Filogenia , Estrutura Terciária de Proteína , RNA Viral/genética , Vírus Reordenados/genética , República da Coreia/epidemiologia , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
15.
Nucleic Acids Res ; 36(Database issue): D455-60, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17982173

RESUMO

Biomarkers enable early diagnosis, guide molecularly targeted therapy and monitor the activity and therapeutic responses across a variety of diseases. Despite intensified interest and research, however, the overall rate of development of novel biomarkers has been falling. Moreover, no solution is yet available that efficiently retrieves and processes biomarker information pertaining to infectious diseases. Infectious Disease Biomarker Database (IDBD) is one of the first efforts to build an easily accessible and comprehensive literature-derived database covering known infectious disease biomarkers. IDBD is a community annotation database, utilizing collaborative Web 2.0 features, providing a convenient user interface to input and revise data online. It allows users to link infectious diseases or pathogens to protein, gene or carbohydrate biomarkers through the use of search tools. It supports various types of data searches and application tools to analyze sequence and structure features of potential and validated biomarkers. Currently, IDBD integrates 611 biomarkers for 66 infectious diseases and 70 pathogens. It is publicly accessible at http://biomarker.cdc.go.kr and http://biomarker.korea.ac.kr.


Assuntos
Biomarcadores/química , Doenças Transmissíveis/diagnóstico , Bases de Dados Factuais , Biomarcadores/análise , Carboidratos/química , Doenças Transmissíveis/terapia , Humanos , Internet , Conformação Molecular , Ácidos Nucleicos/química , Proteínas/química , Análise de Sequência , Interface Usuário-Computador
16.
Nat Commun ; 11(1): 3616, 2020 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-32680987

RESUMO

Genomic and precision medicine research has afforded notable advances in human cancer treatment, yet applicability to other species remains uncertain. Through whole-exome and transcriptome analyses of 191 spontaneous canine mammary tumors (CMTs) that exhibit the archetypal features of human breast cancers, we found a striking resemblance of genomic characteristics including frequent PIK3CA mutations (43.1%), aberrations of the PI3K-Akt pathway (61.7%), and key genes involved in cancer initiation and progression. We also identified three gene expression-based CMT subtypes, one of which segregated with basal-like human breast cancer subtypes with activated epithelial-to-mesenchymal transition, low claudin expression, and unfavorable disease prognosis. A relative lack of ERBB2 amplification and Her2-enrichment subtype in CMT denoted species-specific molecular mechanisms. Taken together, our results elucidate cross-species oncogenic signatures for a better understanding of universal and context-dependent mechanisms in breast cancer development and provide a basis for precision diagnostics and therapeutics for domestic dogs.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Carcinogênese/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Mamárias Animais/genética , Animais , Mama/patologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Classe I de Fosfatidilinositol 3-Quinases/genética , Estudos de Coortes , Variações do Número de Cópias de DNA , Análise Mutacional de DNA , Conjuntos de Dados como Assunto , Cães , Transição Epitelial-Mesenquimal , Feminino , Humanos , Glândulas Mamárias Animais/patologia , Glândulas Mamárias Animais/cirurgia , Neoplasias Mamárias Animais/mortalidade , Neoplasias Mamárias Animais/patologia , Neoplasias Mamárias Animais/cirurgia , Mutação , Prognóstico , RNA-Seq , Especificidade da Espécie , Sequenciamento do Exoma
17.
J Microbiol Biotechnol ; 17(8): 1308-15, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18051599

RESUMO

ALipase B from Candida antarctica (CalB) displayed on the cell surface of H. polymorpha has been functionally improved for catalytic activity by molecular evolution. CalB was displayed on the cell surface by fusing to a cell-wall anchor motif (CwpF). A library of CalB mutants was constructed by in vivo recombination in H. polymorpha. Several mutants with increased whole-cell CalB activity were acquired from screening seven thousand transformants. The two independent mutants CalB10 and CalB14 showed an approximately 5 times greater whole-cell activity than the wild-type. When these mutants were made as a soluble form, CalB 10 showed 6 times greater activity and CalB14 showed an 11 times greater activity compared with the wild-type. Sequence analyses of mutant CALB genes revealed amino acid substitutions of Leu278Pro in CalB10 and Leu278Pro/Leu219Gln in CalB14. The substituted Pro278 in both mutants was located near the proline site of the alpha10 helix. This mutation was assumed to induce a conformational change in the alpha10 helix and increased the k(cat) value of mutant CalB approximately 6 times. Site-directed mutagenized CalB, LQ (Leu219Gln) was secreted into the culture supernatant at an amount of approximately 3 times more without an increase in the CalB transcript level, compared with the wild-type.


Assuntos
Evolução Molecular Direcionada/métodos , Lipase/metabolismo , Proteínas Recombinantes/metabolismo , Substituição de Aminoácidos/genética , Análise Mutacional de DNA , Proteínas Fúngicas , Cinética , Lipase/genética , Modelos Moleculares , Mutagênese , Mutagênese Sítio-Dirigida , Mutação de Sentido Incorreto , Pichia/genética , Pichia/metabolismo , Estrutura Secundária de Proteína/genética , Transporte Proteico/genética , Proteínas Recombinantes/genética
18.
Lung Cancer ; 113: 106-114, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29110836

RESUMO

OBJECTIVES: Despite initial responses to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) in EGFR mutant non-small cell lung cancer, patients invariably develop acquired resistance. In this study, we performed next-generation sequencing in pre- and post-EGFR-TKI tumor samples to identify novel resistance mechanisms to EGFR-TKIs. MATERIAL AND METHODS: We collected tumor tissues before EGFR-TKI treatment and after progression from 19 NSCLC patients to analyze genomic alterations in 409 cancer related genes. Bioinformatics analyses were used to identify mutations in which the allele frequencies are significantly changed, or newly appeared after progression. RESULTS: Overall, mutation rates and compositions were similar between pre- and post-EGFR-TKI tumors. We identified EGFR T790M as the most common mechanism of acquired resistance (63.2%). No pre-EGFR-TKI tumor had a preexisting T790M mutation, suggesting that tumors acquired T790M mutations following progression on EGFR-TKIs. Compared to T790M-positive tumors, T790M-negative tumors showed relatively high tumor mutation burden and shorter survival, suggesting T790M-negative patients as a potential candidate for immune checkpoint inhibitors. TP53 mutation was also significantly enriched in the T790M-negative tumors. Finally, we described here for the first time a novel missense mutation (T263P), which occurred concurrently with an activating G719A mutation, in the extracellular domain II of EGFR in a patient with poor response to erlotinib. Ba/F3 cells harboring EGFR T263P/G719A mutation showed higher sensitivity to afatinib, compared to gefitinib due to inhibition of EGFR/HER2 heterodimerization. CONCLUSION: Comprehensive genomic analysis of post-EGFR-TKI tumors can provide novel insight into the complex molecular mechanisms of acquired resistance to EGFR-TKIs.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Receptores ErbB/antagonistas & inibidores , Neoplasias Pulmonares/tratamento farmacológico , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Adulto , Idoso , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/efeitos dos fármacos , Feminino , Frequência do Gene , Heterogeneidade Genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida
19.
ACS Appl Mater Interfaces ; 9(30): 25257-25264, 2017 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-28700209

RESUMO

Thin films of a heteropolytungstate, lithium silicotungstate (Li4SiW12O40, termed Li-ST), prepared by a solution process at low temperature, were successfully applied as electron transporting layer (ETL) of planar-type perovskite solar cells (PSCs). Dense and uniform Li-ST films were prepared on FTO glass by depositing a thin Li-ST buffer layer, followed by coating of a main Li-ST layer. The film thickness was controlled by varying the number of coating cycles, consisting of spin-coating and thermal treatment at 150 °C. In particular, by employing 60 nm-thick Li-ST layer obtained by two cycles of coating, the fabricated CH3NH3PbI3 PSC device demonstrates the photovoltaic conversion efficiency (PCE) of 14.26% with JSC of 22.16 mA cm-2, VOC of 0.993 mV and FF of 64.81%. The obtained PCE is significantly higher than that of the PSC employing a TiO2 layer processed at the same temperature (PCE = 12.27%). Spectroscopic analyses by time-resolved photoluminescence and pulsed light-induced transient measurement of photocurrent indicate that the Li-ST layer collects electrons from CH3NH3PbI3 more efficiently and also exhibits longer electron lifetime than the TiO2 layer thermally treated at 150 °C. Thus, Li-ST is considered to be a promising ETL material that can be applied for the fabrication of flexible PSC devices.

20.
Sci Rep ; 7(1): 6849, 2017 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-28754997

RESUMO

In the present study, a dual-functional smart film combining the effects of wavelength conversion and amplification of the converted wave by the localized surface plasmon resonance has been investigated for a perovskite solar cell. This dual-functional film, composed of Au nanoparticles coated on the surface of Y2O3:Eu3+ phosphor (Au@Y2O3:Eu3+) nanoparticle monolayer, enhances the solar energy conversion efficiency to electrical energy and long-term stability of photovoltaic cells. Coupling between the Y2O3:Eu3+ phosphor monolayer and ultraviolet solar light induces the latter to be converted into visible light with a quantum yield above 80%. Concurrently, the Au nanoparticle monolayer on the phosphor nanoparticle monolayer amplifies the converted visible light by up to 170%. This synergy leads to an increased solar light energy conversion efficiency of perovskite solar cells. Simultaneously, the dual-function film suppresses the photodegradation of perovskite by UV light, resulting in long-term stability. Introducing the hybrid smart Au@Y2O3:Eu3+ film in perovskite solar cells increases their overall solar-to-electrical energy conversion efficiency to 16.1% and enhances long-term stability, as compared to the value of 15.2% for standard perovskite solar cells. The synergism between the wavelength conversion effect of the phosphor nanoparticle monolayer and the wave amplification by the localized surface plasmon resonance of the Au nanoparticle monolayer in a perovskite solar cell is comparatively investigated, providing a viable strategy of broadening the solar spectrum utilization.

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