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1.
Bioengineering (Basel) ; 11(4)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38671802

RESUMO

Nanobodies have emerged as promising tools in biomedicine due to their single-chain structure and inherent stability. They generally have convex paratopes, which potentially prefer different epitope sites in an antigen compared to traditional antibodies. In this study, a synthetic phage display nanobody library was constructed and used to identify nanobodies targeting a tumor-associated antigen, the human B7-H3 protein. Combining next-generation sequencing and single-clone validation, two nanobodies were identified to specifically bind B7-H3 with medium nanomolar affinities. Further characterization revealed that these two clones targeted a different epitope compared to known B7-H3-specific antibodies, which have been explored in clinical trials. Furthermore, one of the clones, dubbed as A6, exhibited potent antibody-dependent cell-mediated cytotoxicity (ADCC) against a colorectal cancer cell line with an EC50 of 0.67 nM, upon conversion to an Fc-enhanced IgG format. These findings underscore a cost-effective strategy that bypasses the lengthy immunization process, offering potential rapid access to nanobodies targeting unexplored antigenic sites.

2.
J Ethnopharmacol ; 319(Pt 3): 117347, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37931831

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Jianpi Huayu Decoction (JHD) is an herbal prescription in traditional Chinese medicine based on Sijunzi Decoction to treat patients with colorectal cancer (CRC). Its effects on the inhibition of CRC cell proliferation and tumor growth are promising; however, its multicomponent nature makes a complete understanding of its mechanism challenging. AIM OF THE STUDY: To explore the therapeutic targets and underlying molecular pathways of JHD in CRC treatment using network pharmacology techniques and in vivo validation. MATERIALS AND METHODS: The active ingredients and targets of JHD were identified, compound-target interactions were mapped, and enrichment analyses were conducted. We identified the hub targets of JHD-induced cellular senescence in CRC. The binding affinities between compounds and targets were evaluated through molecular docking. Subsequently, we conducted bioinformatic analyses to compare the expression of hub targets between colorectal tissue and normal tissue. Finally, in vivo experiments were carried out utilizing a xenograft model to assess the effects of JHD on cellular senescence biomarkers. RESULTS: Network pharmacology revealed 129 active ingredients in JHD that were associated with 678 targets, leading to the construction of compound-target and target-pathway networks. Enrichment analyses highlighted key pathways including cellular senescence. Based on this, hub targets associated with cellular senescence were determined and validated. Molecular docking indicated favorable interactions between the active components and hub targets. Gene expression and survival analysis in CRC tissue were consistent with the potential roles of hub genes. Animal experiments showed that JHD triggered cellular senescence and suppressed the growth of CRC by regulating the p53-p21-Rb signaling pathway. CONCLUSIONS: This research adopted network pharmacology, bioinformatics, and animal experiments to unveil that JHD induces cellular senescence in CRC by influencing the p53-p21-Rb pathway and senescence-associated secretory phenotypes, highlighting its potential as a CRC treatment.


Assuntos
Neoplasias Colorretais , Farmacologia em Rede , Animais , Humanos , Simulação de Acoplamento Molecular , Proteína Supressora de Tumor p53/genética , Senescência Celular , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética
3.
Gene ; 893: 147940, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37907182

RESUMO

Previous observational studies have indicated an association between hair color and the risk of melanoma and keratinocyte skin cancer (KSC); however, different hair colors show inconsistent effects on skin cancers. Here, we conducted a two-sample Mendelian randomization (MR) study to evaluate the causal relationship between natural hair color and skin cancers by using 211 single nucleotide polymorphisms as genetic instruments from a genome-wide meta-analysis of 360,270 individuals of European ancestry. Light hair colors (red, blonde, and light brown) were associated with high levels of cutaneous melanoma (CM) and KSC (CM-inverse variance weighted [IVW] odds ratio [OR]-red: 1.034, 95% confidence interval [CI]: 1.025-1.044, P < 0.001; OR-blonde: 1.008, 95% CI: 1.003-1.014, P = 0.003; OR-light brown: 1.006, 95% CI: 1.002-1.011, P = 0.009; KSC-IVW OR-red: 1.078, 95% CI: 1.053-1.103, P < 0.001; OR-blonde: 1.024, 95% CI: 1.009-1.040, P = 0.002; OR-light brown: 1.018, 95% CI: 1.004-1.033, P = 0.01). However, dark brown hair showed an inverse causal relationship with skin cancers (CM IVW OR: 0.987, 95% CI: 0.984-0.990, P < 0.001; KSC IVW OR: 0.979, 95% CI: 0.970-0.988, P < 0.001). Black hair was associated with a decreased risk of KSC (IVW OR: 0.954, 95% CI: 0.913-0.997, P = 0.036) but showed no causal relationship with CM. The present study provides strong MR evidence of a causal association between hair color and skin cancer. Secondary MR analyses enhances result robustness by replicating findings, exploring gender-specific effects, and providing a more comprehensive understanding of the complex relationship between hair color and skin cancers. More large-scale MR studies or randomized controlled trials are required to further investigate the mechanisms of the association between hair color and skin cancers.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Neoplasias Cutâneas/genética , Melanoma/genética , Cor de Cabelo/genética , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único , Estudo de Associação Genômica Ampla , Melanoma Maligno Cutâneo
4.
Planta ; 258(3): 61, 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37542564

RESUMO

MAIN CONCLUSION: High expressions of nitrate use and photosynthesis-related transcripts contribute to the stronger plasticity to high nitrate for the invader relative to its native congener, which may be driven by hormones. Strong phenotypic plasticity is often considered as one of the main mechanisms underlying exotic plant invasions. However, few studies have been conducted to investigate the related molecular mechanisms. Here, we determined the differences in the plastic responses to high nitrate between the invasive plant X. strumarium and its native congener, and the molecular bases by transcriptome analysis and quantitative real-time PCR validation. Our results showed that the invader had higher plasticity of growth, nitrogen accumulation and photosynthesis in responses to high nitrate than its native congener. Compared with its congener, more N utilization-related transcripts, including nitrate transporter 1/peptide transporter family 6.2 and nitrate reductase 1, were induced by high nitrate in the root of X. strumarium, improving its N utilization ability. More transcripts coding for photosynthetic antenna proteins were also induced by high nitrate in the shoot of X. strumarium, enhancing its photosynthesis. Hormones may be involved in the regulation of the plastic responses to high nitrate in the two species. Our study contributes to understanding the molecular mechanisms underlying the stronger plasticity of the invader in responses to high nitrate, and the potential function of plant hormones in these processes, providing bases for precise control of invasive plants using modern molecular techniques.


Assuntos
Nitratos , Xanthium , Nitratos/farmacologia , Nitratos/metabolismo , Xanthium/genética , Xanthium/metabolismo , Plantas , Fotossíntese/genética , Hormônios/metabolismo
5.
J Transl Med ; 21(1): 510, 2023 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-37507803

RESUMO

Metabolic dysfunction-associated fatty liver disease (MAFLD) is among the most widespread metabolic disease globally, and its associated complications including insulin resistance and diabetes have become threatening conditions for human health. Previous studies on non-alcoholic fatty liver disease (NAFLD) were focused on the liver's lipid metabolism. However, growing evidence suggests that mitochondrial metabolism is involved in the pathogenesis of NAFLD to varying degrees in several ways, for instance in cellular division, oxidative stress, autophagy, and mitochondrial quality control. Ultimately, liver function gradually declines as a result of mitochondrial dysfunction. The liver is unable to transfer the excess lipid droplets outside the liver. Therefore, how to regulate hepatic mitochondrial function to treat NAFLD has become the focus of current research. This review provides details about the intrinsic link of NAFLD with mitochondrial metabolism and the mechanisms by which mitochondrial dysfunctions contribute to NAFLD progression. Given the crucial role of mitochondrial metabolism in NAFLD progression, the application potential of multiple mitochondrial function improvement modalities (including physical exercise, diabetic medications, small molecule agonists targeting Sirt3, and mitochondria-specific antioxidants) in the treatment of NAFLD was evaluated hoping to provide new insights into NAFLD treatment.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Fígado/patologia , Estresse Oxidativo , Mitocôndrias/metabolismo , Antioxidantes/metabolismo
6.
Plant Sci ; 328: 111542, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36563940

RESUMO

Reblooming bearded iris (Iris spp.) could bloom in both spring and autumn, which has extended the ornamental periods. Our previous transcriptome analysis has indicated the possible regulatory role of SHORT VEGETATIVE PHASE (SVP) in reblooming of bearded iris. Moreover, it has been revealed that the mutations of TERMINAL FLOWER 1 (TFL1) led to the continuous-flowering phenotypes in rose (Rosa spp.) and strawberry (Fragaria spp.). In order to verify the functions of these two genes on reblooming in bearded iris, IgSVP and IgTFL1 were isolated and functionally characterized. All the overexpression Arabidopsis lines of IgSVP and IgTFL1 generated the late-flowering phenotypes, indicating their functions as flowering repressors. The ectopic expression of IgSVP and IgTFL1 also generated phenotypic changes on flowers, inflorescences and branch structures. Moreover, the protein-protein interaction was found between a homologue of IgSVP and the floral meristem identity gene APETALA 1. The expression profiling showed that IgSVP was expressed significantly lower in the rebloomers in the second floral initiation stage (T5) than those of the first one (T1) in both the once-bloomers and the rebloomers, suggesting the possible regulation of IgSVP on reblooming. However, the expression level of IgTFL1 in the rebloomers was significantly higher in T5 than that in T1. The functional characterization of the two important flowering repressors IgSVP and IgTFL1 could lay solid foundation for future molecular breeding of iris, for example, knocking out the key repressors by CRISPR/Cas9 system to extend the ornamental periods of bearded iris.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Flores/metabolismo , Arabidopsis/metabolismo , Inflorescência/genética , Fatores de Transcrição/metabolismo , Regulação da Expressão Gênica de Plantas
7.
Front Plant Sci ; 13: 1035137, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36388472

RESUMO

Soil nitrogen forms are important for exotic plant invasions. However, little effort has been made to study the molecular mechanisms underlying the utilization of different N forms in co-occurring invasive and native plants. The invasive plant Xanthium strumarium prefers nitrate relative to ammonium, and mainly invades nitrate-dominated environments, while it co-occurring native congener X. sibiricum prefers ammonium. Here, we addressed the genetic bases for the interspecific difference in ammonium use and the effects of gibberellin (GA). Twenty-six transcripts related with GA biosynthesis and ammonium utilization were induced by ammonium in X. sibiricum, while only ten in X. strumarium and none for ammonium uptake. XsiAMT1.1a, XsiGLN1.1 and XsiGLT1b may be crucial for the strong ability to absorb and assimilate ammonium in X. sibiricum. All tested transcripts were significantly up-regulated by GA1 and GA4 in X. sibiricum. XsiGA3OX1a, which was also induced by ammonium, may be involved in this regulation. Consistently, glutamine synthetase activity increased significantly with increasing ammonium-N/nitrate-N ratio for X. sibiricum, while decreased for X. strumarium. Our study is the first to determine the molecular mechanisms with which invasive and native plants use ammonium differently, contributing to understanding the invasion mechanisms of X. strumarium and its invasion habitat selection.

8.
Front Bioeng Biotechnol ; 10: 884797, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35573224

RESUMO

Otitis media (OM) is a common disease in children. One of the most common pathogens causing OM is non-typeable Haemophilus influenzae (NTHi). NTHi in the middle ear can be successfully eradicated by a regimen of oral antibiotics sustained for 7-10 days (e.g., cefuroxime axetil 250 mg/day for patients aged 3 months to 2 years and 500 mg/day for patients ages ≥2 years). However, lack of compliance is relevant to treatment failure or early relapse. In order to overcome these challenges, we have developed antibiotics-loaded bioadhesive nanoparticles (BNPs) that can adhere to the epidermis of the middle ear after local administration and significantly prolong the release time of antibiotics in the middle ear. Compared with oral administration of CA, local delivery of free antibiotic cefuroxime axetil (CA), and CA loaded non-bioadhesive nanoparticles (CA/NNPs), BNPs loaded with cefuroxime axetil (CA/BNPs) showed significantly longer retention time in the middle ear, resulting in continuous release of the drug and higher therapeutic efficacy against OM with only a single dosage. CA concentrations were maintained above the minimum inhibitory concentration (MIC) for NTHi throughout 7 days' treatment. NTHi OM in a mouse model was successfully eradicated without causing tissue toxicity. CA/BNPs minimize systemic drug exposure through local administration, as demonstrated by undetectable levels in the blood.

9.
Phytochem Anal ; 33(2): 239-248, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34390060

RESUMO

INTRODUCTION: The roots of Stephania succifera are used in traditional medicine for the treatment of several diseases. Research on this plant has mainly focused on bioactive alkaloids from the roots, and no previous work on compounds from the abundant leaves has yet been reported. OBJECTIVE: To identify and compare alkaloidal compounds in S. succifera roots and leaves and to predict the potential bioactivity of some alkaloids. METHODS: High-performance liquid chromatography with quadrupole time-of-flight tandem mass spectrometry (HPLC-QTOF-MS/MS) was employed to identify alkaloidal compounds from S. succifera. The potential targets and bioactivities of most alkaloids were predicted using the PharmMapper server. RESULTS: Fifty-six alkaloidal compounds, including protoberberine-, aporphine-, proaporphine-, benzylisoquinoline-, and lactam-type alkaloids, were identified or tentatively identified in S. succifera roots and leaves based on the HPLC-MS data. Forty-one compounds have not been previously reported in S. succifera and eight of them have not been previously reported in the literature. Twenty-four alkaloidal compounds were found in both roots and leaves. Twelve potential targets with different indications were predicted for some alkaloids. CONCLUSION: Comparison of chemical constituents and their potential bioactivities for S. succifera roots and leaves indicated that diverse bioactive alkaloids were present in the leaves as well as the roots. PharmMapper provided new directions for bioactivity screening. This study will be helpful for further understanding the medicinal components of S. succifera and the rational utilisation of plant resources.


Assuntos
Alcaloides , Stephania , Alcaloides/análise , Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/química , Folhas de Planta/química , Stephania/química , Espectrometria de Massas em Tandem/métodos
10.
Int J Syst Evol Microbiol ; 70(10): 5417-5424, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32886591

RESUMO

A Gram-stain-negative, moderately halophilic strain, designated strain L5T, was isolated from wetsalted hides collected from Chengdu, south-west PR China. The cells were motile, facultative aerobic, short rod-shaped and non-endospore-forming. Growth of strain L5T occurred at pH 6-10 (optimum, pH 8), 10-45 °C (optimum, 30 °C) and in the presence of 1-17 % (w/v) NaCl (optimum, 10 %). Results of phylogenetic analyses based on 16S rRNA, gyrB and rpoD gene sequences and its genome revealed that strain L5T belonged to the genus Halomonas. Strain L5T was found to be most closely related to the type strains of Halomonas saliphila, Halomonas lactosivorans, Halomonas kenyensis, Halomonas daqingensis and Halomonas desiderata (98.8, 98.6, 98.3, 97.9 and 97.4 % 16S rRNA gene sequence similarity, respectively). The draft genome was approximately 4.2 Mb in size with a G+C content of 63.5 mol%. The average nucleotide identity (ANI) and digital DNA-DNA hybridization values among strain L5T and the selected Halomonas species were 83.3-88.9 % (ANIm), 71.1-87.3 % (ANIb) and 20.2-34.6 %, which are below the recommended cutoff values. Major fatty acids were C16 : 0, C16 : 1 ω7c, C18 : 1 ω7c and C19 : 0 cyclo ω8c and the predominant ubiquinone was Q-9, with minor ubiquinone Q-8 also present. The phospholipid profile consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, four unidentified aminophospholipids and three unidentified phospholipids. Based on the mentioned polyphasic taxonomic evidence, strain L5T represents a novel species within the genus Halomonas, for which Halomonas pellis sp. nov. is proposed. The type strain is L5T (=CGMCC 1.17335T=KCTC 72573T).


Assuntos
Cabras/microbiologia , Halomonas/classificação , Filogenia , Pele/microbiologia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Halomonas/isolamento & purificação , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Cloreto de Sódio , Ubiquinona/química
11.
J Microbiol Biotechnol ; 30(7): 1082-1091, 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32325545

RESUMO

Microbial transglutaminases (MTGs) are widely used in the food industry. In this study, the MTG gene of Streptomyces sp. TYQ1024 was cloned and expressed in a food-grade bacterial strain, Bacillus subtilis SCK6. Extracellular activity of the MTG after codon and signal peptide (SP Ync M) optimization was 20 times that of the pre-optimized enzyme. After purification, the molecular weight of the MTG was 38 kDa and the specific activity was 63.75 U/mg. The optimal temperature and pH for the recombinant MTG activity were 50°C and 8.0, respectively. MTG activity increased 1.42- fold in the presence of ß-ME and 1.6-fold in the presence of DTT. Moreover, 18% sodium chloride still resulted in 83% enzyme activity, which showed good salt tolerance. Cross-linking gelatin with the MTG increased the strength of gelatin 1.67 times and increased the thermal denaturation temperature from 61.8 to 75.8°C. The MTG also significantly increased the strength and thermal stability of gelatin. These characteristics demonstrated the huge commercial potential of MTG, such as for applications in salted protein foods.


Assuntos
Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Gelatina/genética , Gelatina/metabolismo , Sinais Direcionadores de Proteínas/genética , Transglutaminases/genética , Transglutaminases/metabolismo , Proteínas de Bactérias/genética , Clonagem Molecular , Códon , Regulação Bacteriana da Expressão Gênica , Concentração de Íons de Hidrogênio , Cinética , Streptomyces/genética , Temperatura
12.
3 Biotech ; 9(4): 132, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30863711

RESUMO

Human oral streptococci, particularly the mitis group, often dwell in the upper respiratory tracts, oral mucosa, and tooth surfaces of healthy individuals. In this work, an α-hemolytic strain, designated LQJ-218, was isolated from the human oral cavity and evaluated for its ability to produce exopolysaccharides. Phylogenetic analysis based on 16S rRNA gene sequences showed that this strain is a potentially novel species belonging to the mitis group streptococci. Whole-genome sequence-based analysis indicated that the genome sequence of Streptococcus sp. LQJ-218 was 1,935,194 bp in length, with a mol% G + C content of 40.0, and contained 1897 coding DNA sequences and 91 RNA genes. Furthermore, four biosynthetic gene clusters relevant to exopolysaccharide production were identified in the genome. Both digital DNA-DNA hybridization (yielding a value of 56.60% between strain LQJ-218 and its nearest relative S. mitis) and average nucleotide identity analysis (revealing 91.29% identity of LQJ-218 with its nearest relative S. mitis) suggested that strain LQJ-218 should be classified as a novel Streptococcus species. This potentially novel strain may possess great potential for contributing to the development of new exopolysaccharides. The present study provides valuable genetic information that may be useful in comparative genomics and biotechnological applications.

13.
Carbohydr Polym ; 154: 13-9, 2016 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-27577891

RESUMO

The oxidized amyloses with different carboxyl content were prepared to include linalool for antimicrobial activity in aqueous environment. The results show that linalool can be effectively reserved from volatilization through encapsulation into amylose and oxidized amyloses. The inclusion ability of oxidized amyloses towards linalool is decreasing with the increase of oxidation level due to the depolymerization of amylose. However, the solubilization effect of oxidized amyloses to linalool is enhanced efficiently owning to the high water solubility of oxidized amyloses. It is interesting that the inclusion complexes have good antimicrobial activity in aqueous environment. Linalool solubilized by oxidized amyloses presents better antimicrobial performance than that solubilized by amylose, mainly resulting from that amylose-linalool inclusion complex would aggregate and retrograde fast in aqueous solution, which is disadvantageous for the release of linalool. The study suggests that oxidized amylose is a promising solubilizer and carrier of linalool for antimicrobial activity in aqueous environment.


Assuntos
Amilose/administração & dosagem , Amilose/química , Anti-Infecciosos/administração & dosagem , Portadores de Fármacos/química , Monoterpenos/administração & dosagem , Monoterpenos Acíclicos , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Portadores de Fármacos/administração & dosagem , Liberação Controlada de Fármacos , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Monoterpenos/química , Monoterpenos/farmacologia , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Difração de Raios X
14.
Small ; 10(22): 4700-10, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25115777

RESUMO

The integration of novel surface-enhanced Raman scattering (SERS) nanoprobes and a microfluidic dielectrophoresis (DEP) device is developed for rapid on-line SERS detection of Salmonella enterica serotype Choleraesuis and Neisseria lactamica. The SERS nanoprobes are prepared by immobilization of specific antibody onto the surface of nanoaggregate-embedded beads (NAEBs), which are silica-coated, dye-induced aggregates of a small number of gold nanoparticles (AuNPs). Each NAEB gives highly enhanced Raman signals owing to the presence of well-defined plasmonic hot spots at junctions between AuNPs. Herein, the on-line SERS detection and accurate identification of suspended bacteria with a detection capability down to a single bacterium has been realized by the NAEB-DEP-Raman spectroscopy biosensing strategy. The practical detection limit with a measurement time of 10 min is estimated to be 70 CFU mL(-1) . In comparison with whole-cell enzyme-linked immunosorbent assay (ELISA), the SERS-nanoprobe-based biosensing method provides advantages of higher sensitivity and requiring lower amount of antibody in the assay (100-fold less). The total assay time including sample pretreatment is less than 2 h. Hence, this sensing strategy is promising for faster and effective on-line multiplex detection of single pathogenic bacterium by using different bioconjugated SERS nanoprobes.


Assuntos
Eletroforese/instrumentação , Microfluídica/instrumentação , Sondas Moleculares , Salmonella enterica/isolamento & purificação , Análise Espectral Raman/métodos , Ensaio de Imunoadsorção Enzimática , Nanopartículas Metálicas , Microscopia Eletrônica de Transmissão
15.
Opt Express ; 21(4): 4167-73, 2013 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-23481950

RESUMO

The Cr³âºâ‚‹Yb³âº codoped YAG crystals were synthesized by the solid state reaction method, in which the intense near-infrared emission around 1000 nm originated from Yb³âº ²F5/2 →²F7/2 transition was obtained due to the efficient energy transfer from Cr³âº to Yb³âº. The stable and transient spectral measurements revealed that the phonon assistant energy transfer process is responsible for the energy transfer from Cr³âº to Yb³âº upon both the excitations of Cr³âº: 4T1 and 4T2> energy levels. Due to the effective absorption of Cr³âº in the visible region in YAG and the efficient energy transfer to Yb³âº, this material can be developed as spectral convertors to improve silicon solar cell photovoltaic conversion efficiency.


Assuntos
Fontes de Energia Elétrica , Medições Luminescentes/instrumentação , Energia Solar , Desenho de Equipamento , Análise de Falha de Equipamento
16.
BMC Cancer ; 10: 610, 2010 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-21054888

RESUMO

BACKGROUND: Oridonin, a tetracycline diterpenoid compound, has the potential antitumor activities. Here, we evaluate the antitumor activity and action mechanisms of oridonin in colorectal cancer. METHODS: Effects of oridonin on cell proliferation were determined by using a CCK-8 Kit. Cell cycle distribution was determined by flow cytometry. Apoptosis was examined by analyzing subdiploid population and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. Senescent cells were determined by senescence-associated ß-galactosidase activity analysis. Semi-quantitative RT-PCR was used to examine the changes of mRNA of p16, p21, p27 and c-myc. The concomitant changes of protein expression were analyzed with Western blot. Expression of AcH3 and AcH4 were examined by immunofluorescence staining and Western blots. Effects of oridonin on colony formation of SW1116 were examined by Soft Agar assay. The in vivo efficacy of oridonin was detected using a xenograft colorectal cancer model in nude mice. RESULTS: Oridonin induced potent growth inhibition, cell cycle arrest, apoptosis, senescence and colony-forming inhibition in three colorectal cancer cell lines in a dose-dependent manner in vitro. Daily i.p. injection of oridonin (6.25, 12.5 or 25 mg/kg) for 28 days significantly inhibited the growth of SW1116 s.c. xenografts in BABL/C nude mice. With western blot and reverse transcription-PCR, we further showed that the antitumor activities of oridonin correlated with induction of histone (H3 and H4) hyperacetylation, activation of p21, p27 and p16, and suppression of c-myc expression. CONCLUSION: Oridonin possesses potent in vitro and in vivo anti-colorectal cancer activities that correlated with induction of histone hyperacetylation and regulation of pathways critical for maintaining growth inhibition and cell cycle arrest. Therefore, oridonin may represent a novel therapeutic option in colorectal cancer treatment.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Inibidor de Quinase Dependente de Ciclina p21/genética , Diterpenos do Tipo Caurano/farmacologia , Regulação Neoplásica da Expressão Gênica , Histonas/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogênicas c-myc/genética , Acetilação , Animais , Apoptose , Senescência Celular , Neoplasias Colorretais/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p27 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias , beta-Galactosidase/metabolismo
17.
J Exp Clin Cancer Res ; 29: 141, 2010 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-21054902

RESUMO

BACKGROUND: To study on expressions and clinical significances of CD133 protein and CD133 mRNA in primary lesion of gastric adenocarcinoma (GC). METHODS: Expressions of CD133 protein by immunostaining (99 cases) and CD133 mRNA by semi-quantitative RT-PCR (31 cases) were detected in primary lesion and in noncancerous gastric mucosa tissue (NCGT). Correlations of CD133 protein expression with clinicopathological parameters and post-operative survival were analyzed. Relations of CD133 mRNA level with Ki-67 labeling index (LI), and lymphatic metastasis were assessed too. RESULTS: Brown particles indicating CD133 protein positivity occurred in some parts of tumor cells and epithelium. Expressive percentage of CD133 protein positivity was significantly higher in subgroups with >5 cm diameter (P = 0.041), later TNM stage (P = 0.044), severer lymph node metastasis (P = 0.017), occurrences of lymphatic invasion (P = 0.000) and vascular invasion (P = 0.000) respectively. Severer invasion depth (P = 0.011), lymph node metastasis occurrence (P = 0.043) and later TNM stage (P = 0.049) were the independent risk factors for CD133 protein expression. Average brightness scale value (BSV) of CD133 mRNA was significantly higher in subgroups with >5 cm diameter (P = 0.041), lymph node metastasis occurrence (P = 0.004) and in lower Ki-67 LI (P = 0.02). Relative analysis revealed that BSV of CD133 mRNA related positively to metastatic lymphatic nodes ratio (P = 0.008) and metastatic lymph node number (P = 0.009), but negatively to Ki-67 LI (P = 0.009). Survival of positive subgroup of CD 133 protein was significantly poorer (P = 0.047). Lymph node metastasis occurrence (P = 0.042), later TNM stage (P = 0.046) and CD 133 protein positive expression (P = 0.046) were respectively the independent risk factors to survival. CONCLUSION: Higher expressive level of CD133 mRNA is associated to lower Ki-67 LI and severer lymphatic metastasis. Therefore, the expressive level of CD133 mRNA can play an appropriate role to reflect the status of lymph node metastasis and proliferation of GC. CD133 protein expression is closely related with larger tumor, later TNM stage, lymphtic metastasis and survival of GC.


Assuntos
Adenocarcinoma/química , Antígenos CD/análise , Glicoproteínas/análise , Peptídeos/análise , RNA Mensageiro/análise , Neoplasias Gástricas/química , Antígeno AC133 , Adenocarcinoma/genética , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD/genética , Distribuição de Qui-Quadrado , China , Feminino , Glicoproteínas/genética , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Antígeno Ki-67/análise , Modelos Logísticos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Peptídeos/genética , Prognóstico , Modelos de Riscos Proporcionais , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Medição de Risco , Fatores de Risco , Neoplasias Gástricas/genética , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Taxa de Sobrevida
18.
Biomed Pharmacother ; 64(3): 184-90, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20053523

RESUMO

The effects of a small interfering RNA targeting ryanodine receptor 2 (si-Ryr2) on cardiomyocytes injury following a simulated ischemia-reperfusion (I/R) were investigated. Pretreated with si-Ryr2 or ryanodine, primary cultures of neonatal rat cardiomyocytes were subjected to a protocol of simulated I/R. Compared with control, the cytosolic Ca(2+) concentration ([Ca(2+)](i)) and the generation of reactive oxygen species (ROS) was significantly augmented after I/R. Concomitant with these, cell injury assessed by Annexin V/PI staing, mitochondria membrane potential (DeltaPsim) and the leakage of lactic dehydrogenase (LDH) and creatine phosphokinase (CPK) were aggravated. Si-Ryr2 treatment reduced [Ca(2+)](i) and ROS generation and protected the cardiomyocytes from subsequent I/R injury, as evidenced by stable DeltaPsim and decreased Annexin V(+) PI(-) staing and enzymes release. Moreover, si-Ryr2 exerted more effective protection on I/R injury compared to ryanodine. The present study demonstrated for the first time that in neonatal cardiomyocytes, si-Ryr2 reduces cell death associated with attenuating [Ca(2+)](i) and ROS production. Furthermore, we attempt to speculate that si-Ryr2 excel ryanodine in Ryr2 function research of cardioprotection.


Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miócitos Cardíacos/efeitos dos fármacos , Interferência de RNA , RNA Interferente Pequeno/farmacologia , Canal de Liberação de Cálcio do Receptor de Rianodina/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Sinalização do Cálcio/fisiologia , Dióxido de Carbono/farmacologia , Células Cultivadas/efeitos dos fármacos , Técnicas In Vitro , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Cardíacas/efeitos dos fármacos , Nitrogênio/farmacologia , Oxigênio/farmacologia , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Rianodina/farmacologia , Canal de Liberação de Cálcio do Receptor de Rianodina/biossíntese , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/fisiologia
19.
Yao Xue Xue Bao ; 44(6): 586-90, 2009 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-19806887

RESUMO

To investigate the protective effects of recombinant human tumor necrosis factor receptor II: IgG Fc fusion protein (rhu TNFR: Fc) against the lipopolysaccharide (LPS) induced intestinal damage of rats and its underlying mechanism. SD rats were randomly divided into four groups: control group, rhuTNFR: Fc group, LPS group and rhu TNFR: Fc + LPS group. Mean arterial pressure (MAP) was continuously monitored and the mortality rates were assessed. The levels of TNF-alpha and its bioactivity in the serum were assessed by ELISA and flow cytometry respectively. Pathologic changes of intestinal tissue were observed by HE staining. The rats of control and rhu TNFR: Fc group all survived with stable MAP, and the low level and bioactivity of TNF-alpha in the serum were maintained. While 83% of the rats in LPS group died by 6 h with the levels and bioactivity of TNF-alpha increasing significantly. In rhu TNFR: Fc + LPS group, the mortality rate of rats dropped to 33%. The TNF-alpha level increased compared with control group but its bioactivity decreased significantly compared with LPS group. The MPO activity and content of MDA decreased significantly. The status of pathological manifestation in the intestine was also ameliorated. These data suggest that rhu TNFR: Fc could protect rats from the acute intestine injury induced by LPS through ablating the rise in serum TNF-alpha level and bioactivity as well as anti-oxidation.


Assuntos
Imunoglobulina G/farmacologia , Intestinos/efeitos dos fármacos , Intestinos/patologia , Animais , Modelos Animais de Doenças , Etanercepte , Feminino , Humanos , Mucosa Intestinal/metabolismo , Lipopolissacarídeos/efeitos adversos , Masculino , Ratos , Ratos Sprague-Dawley , Receptores do Fator de Necrose Tumoral , Receptores Tipo II do Fator de Necrose Tumoral/farmacologia , Proteínas Recombinantes de Fusão/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
20.
Biomed Pharmacother ; 63(7): 537-42, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18848768

RESUMO

Tumor necrosis factor-alpha (TNF-alpha) is thought to play a major role in systemic inflammation associated with sepsis. A potent TNF antagonist, a recombinant fusion protein that consists of the soluble TNF receptor (p75) linked to the Fc portion of human IgG1 (sTNFR II/IgG1 Fc fusion protein, sTNFR:Fc), has been shown to provide rapid and sustained improvement in local inflammation diseases by binding TNF-alpha and preventing its proinflammatory activities. To explore the potential therapeutic efficacy for septic shock of sTNFR:Fc, we investigate the effect of this molecule on the survival rate, blood pressure, serum TNF-alpha bioactivity as well as the expression of TNF-alpha at mRNA level in the liver in a LPS-induced rat septic shock model. Blood pressure of the rats was monitored by multi-channel creature signal analysis system. Serum TNF-alpha level and bioactivity was assessed using an enzyme-linked immunoassay and a L929 cytotoxicity assay, respectively. The expression of TNF-alpha mRNA in liver was examined by semi-quantitative RT-PCR. sTNFR:Fc administered to rats 24h before LPS challenge ablated the rise in serum TNF-alpha bioactivity that occurs in response to LPS and protected against hypotension and death. These results indicate that TNF-alpha is a mediator of fatal septic shock, and suggest that sTNFR:Fc offer a potential therapy of systemic infection.


Assuntos
Imunoglobulina G/uso terapêutico , Fatores Imunológicos/uso terapêutico , Receptores do Fator de Necrose Tumoral/uso terapêutico , Choque Séptico/tratamento farmacológico , Animais , Pressão Sanguínea/efeitos dos fármacos , Etanercepte , Humanos , Lipopolissacarídeos/farmacologia , Fígado/metabolismo , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , Choque Séptico/mortalidade , Choque Séptico/fisiopatologia , Taxa de Sobrevida , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/sangue , Fator de Necrose Tumoral alfa/genética
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