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2.
Beijing Da Xue Xue Bao Yi Xue Ban ; 55(6): 1013-1021, 2023 Dec 18.
Artículo en Chino | MEDLINE | ID: mdl-38101782

RESUMEN

OBJECTIVE: To investigate the efficacy and safety of iguratimod combined with tofacitinib in patients with difficult-to-treat moderate-to-severe rheumatoid arthritis (RA). METHODS: In this prospective clinical study, 30 patients with difficult-to-treat moderate-to-severe RA who attended the Department of Rheumatology and Immunology of Shanxi Province Fenyang Hospital from September 2021 to June 2022 were selected. Twenty-three patients enrollment had been treated with 2 or more conventional synthetic disease modifying anti-rheumatic drugs (DMARDs) for more than 6 months. At least, methotrexate or leflunomide was included. Seven patients were treated with conventional synthetic DMARDs combined with tumor necrosis factor antagonists. Because all the patients had not reached the target of treatment, the combination treatment regimen of DMARDs was changed to iguratimod and tofacitinib. The observation period was 12 weeks. Clinical data were collected before and after treatment. At the end of 4 weeks, 8 weeks and 12 weeks, the clinical data were collected such as swollen joints count (SJC), tender joints count (TJC), time of morning stiffness, clinical disease activity index (CDAI), health status assessment questionnaire (HAQ), and 28-joint disease activity score (DAS28) were included. We collected laboratory indicators, recorded the patient's medication, and observed some changes to see if any adverse drug reactions occurred during the treatment. RESULTS: There were significant differences in erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), rheumatoid factor (RF), platelet (PLT), SJC, TJC, DAS28 based on ESR(DAS28-ESR), time of morning stiffness, HAQ, CDAI, and anti-cyclic citrullinated peptide antibody before and after treatment. The differences had statistical significance (P < 0.05). There was no statistical differences in globulin before and after treatment (P>0.05). During the treatment of iguratimod combined with tofacitinib, there was no serious adverse reactions such as leukopenia, significant elevation of liver enzymes, allergy or thromboemblolic events that occurred in all the patients. CONCLUSION: Iguratimod combined with tofacitinib in the treatment of difficult-to-treat moderate-to-severe RA may have efficacy. The machanism was improving the patients' recent clinical symptoms by reducing inflammatory indexes. This combination treatment regimen with iguratimod and tofacitinib has a good safety profile.


Asunto(s)
Antirreumáticos , Artritis Reumatoide , Humanos , Estudios Prospectivos , Artritis Reumatoide/tratamiento farmacológico , Antirreumáticos/uso terapéutico , Resultado del Tratamiento
3.
Microb Biotechnol ; 16(6): 1373-1392, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36965164

RESUMEN

In order to address the global crisis in pear productivity, there has been increased attention given to advocating for the use of organic fertilizers. As part of this effort, researchers have been investigating the microbial properties of organic fertilizers to better understand their potential impact on fruit productivity. Our research focused specifically on the impact of four different ratios of sheep manure (SM) and chemical fertilizers (CF) on pear productivity. We found that replacing CF with SM resulted in a proliferation of gammaproteobacteria, Chlamydiae, Bastocatellia and Clostridia in the soil rhizosphere, which is the region around the roots of plants where most nutrient uptake occurs. Using redundancy analysis, we were able to determine that SM was particularly effective at promoting the growth of gammaproteobacteria and clostridia, which were associated with C:N ratios around 14:1 as well as the availability of K, Fe, Zn and Cu. This combination of factors was conducive to a transition from vegetative growth to reproductive growth, resulting in an increase in pear production from 43 to 56 tons per hectare. We also discovered that Blastociella acts as a buffering system in regulating soil acidity. Taken together, our findings indicate that a combination of SM and CF can improve the abundance of beneficial bacteria in the rhizosphere, leading to an increase in pear productivity.


Asunto(s)
Microbiota , Pyrus , Animales , Ovinos , Fertilizantes/análisis , Frutas/química , Rizosfera , Microbiota/fisiología , Suelo/química , Bacterias/genética , Firmicutes , Microbiología del Suelo , Estiércol/microbiología
4.
Front Immunol ; 13: 920253, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35911687

RESUMEN

Background: Patients with early-stage laryngeal cancer, even stage T1-2N0, are at considerable risk of recurrence and death. The genetic and immunologic characteristics of recurrent laryngeal cancer remain unclear. Methods: A total of 52 T1-2N0 laryngeal cancer patients were enrolled. Of these, 42 tissue samples were performed by targeted DNA sequencing, and 21 cases were performed by NanoString immuno-oncology targeted RNA sequencing to identify the distinct molecular bases and immunologic features associated with relapse in patients with early laryngeal cancer, respectively. Results: To the best to our knowledge, we present for the first time an overview of the genomic mutation spectrum of early-stage laryngeal cancers. A total of 469 genomic alterations were detected in 211 distinct cancer-relevant genes, and the genes found to be mutated in more than five patients (>10%) included tumor protein p53 (TP53, 78.5%), FAT atypical cadherin 1 (FAT1, 26%), LDL receptor related protein 1B (LRP1B, 19%), cyclin dependent kinase inhibitor 2A (CDKN2A, 17%), tet methylcytosine dioxygenase 2 (TET2, 17%), notch receptor 1 (NOTCH1, 12%) and neuregulin 1 (NRG1, 12%). Recurrent laryngeal cancer demonstrated a higher tumor mutation burden (TMB), as well as higher LRP1B mutation and NOTCH1 mutation rates. Univariate and multivariate analyses revealed that high TMB (TMB-H) and NOTCH1 mutation are independent genetic factors that are significantly associated with shorter relapse-free survival (RFS). Simultaneously, the results of the transcriptome analysis presented recurrent tumors with NOTCH1 mutation displayed upregulation of the cell cycle pathway, along with decreased B cells score, T cells score, immune signature score and tumor-infiltrating lymphocytes (TILs) score. The Cancer Genome Atlas (TCGA)-laryngeal cancer dataset also revealed weakened immune response and impaired adhesion functions in NOTCH1-mutant patients. Conclusions: Genomic instability and impaired immune response are key features of the immunosurveillance escape and recurrence of early laryngeal cancer after surgery. These findings revealed immunophenotypic attenuation in recurrent tumors and provided valuable information for improving the management of these high-risk patients. Due to the small number of patients in this study, these differences need to be further validated in a larger cohort.


Asunto(s)
Neoplasias Laríngeas , Receptor Notch1 , Inhibidor p16 de la Quinasa Dependiente de Ciclina , Humanos , Inmunidad/genética , Neoplasias Laríngeas/complicaciones , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/cirugía , Mutación , Recurrencia Local de Neoplasia/patología , Receptor Notch1/genética , Receptor Notch1/inmunología
5.
Protein Pept Lett ; 28(9): 1043-1053, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33726638

RESUMEN

BACKGROUND: Thermophilic fungi have recently emerged as a promising source of thermostable enzymes. Superoxide dismutases are key antioxidant metalloenzymes with promising therapeutic effects in various diseases, both acute and chronic. However, structural heterogeneity and low thermostability limit their therapeutic efficacy. OBJECTIVE: Although several studies from hypethermophilic superoxide dismutases (SODs) have been reported, information about Cu,Zn-SODs from thermophilic fungi is scarce. Chaetomium thermophilum is a thermophilic fungus that could provide proteins with thermophilic properties. METHODS: The enzyme was expressed in Pichia pastoris cells and crystallized using the vapor-diffusion method. X-ray data were collected, and the structure was determined and refined to 1.56 Å resolution. Structural analysis and comparisons were carried out. RESULTS: The presence of 8 molecules (A through H) in the asymmetric unit resulted in four different interfaces. Molecules A and F form the typical homodimer which is also found in other Cu,Zn- SODs. Zinc was present in all subunits of the structure while copper was found in only four subunits with reduced occupancy (C, D, E and F). CONCLUSION: The ability of the enzyme to form oligomers and the elevated Thr:Ser ratio may be contributing factors to its thermal stability. Two hydrophobic residues that participate in interface formation and are not present in other CuZn-SODs may play a role in the formation of new interfaces and the oligomerization process. The CtSOD crystal structure reported here is the first Cu,Zn-SOD structure from a thermophilic fungus.


Asunto(s)
Chaetomium/enzimología , Cobre/química , Proteínas Fúngicas/química , Superóxido Dismutasa/química , Zinc/química , Chaetomium/genética , Cristalografía por Rayos X , Estabilidad de Enzimas , Proteínas Fúngicas/genética , Dominios Proteicos , Superóxido Dismutasa/genética
6.
RSC Adv ; 10(16): 9476-9485, 2020 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-35497211

RESUMEN

Three couples of coordination polymers (CPs), namely, [Co((R/S)-Hcna)2] n (1-D/L), [Cd6((1R,2R/1S,2S)-cpba)4(phen)6(H2O)3] n (2-D/L) and [Cd2((1R,2R/1S,2S)-Hcpba)2(phen)2] n (3-D/L) {(R/S)-H2cna = (R/S)-6-(1-carboxyethoxy)-2-naphthoic acid, (1R,2R/1S,2S)-H3cpba = (1R,2R/1S,2S)-2,2'-((5-carboxy-1,3-phenylene)bis(oxy))dipropionic acid, phen = 1,10-phenanthroline} are successfully synthesized under hydrothermal conditions. Structural analysis shows that CP 1 has a 3D 3,6-c net structure with a point symbol of (4·62)2(42·610·83). CPs 2 and 3 are obtained under very similar reaction conditions except using different solvent ratios. The presence of the planar chelating ligand phen in CPs 2 and 3 limited the spatial growth of the structure, resulting in the formation of different 1D structures. All CPs crystallized in the chiral space group P21, CPs 1-3 are all SHG active. Their luminescence sensing activities for organics such as antibiotics, pesticides and nitro aromatics are also investigated. The results showed that CP 1 can effectively identify trace amounts of nitrofurans (NFs) and CP 3 has obvious recognition ability toward nitrofurans (NFs) and nitroimidazoles (NMs). Both CPs 1 and 3 could selectively detect 2,6-dichloro-4-nitroaniline (DCN). The luminescence of CPs 1 and 3 can also be quenched by (D/L)-4-nitrophenylalanine ((D/L)-NPA) and (1R,2R/1S,2S)-2-amino-1-(4-nitrophenyl)propane-1,3-diol ((1R,2R/1S,2S)-ANPO).

7.
Plant Cell ; 31(9): 2131-2151, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31221736

RESUMEN

The receptor-like kinase SIT1 acts as a sensor in rice (Oryza sativa) roots, relaying salt stress signals via elevated kinase activity to enhance salt sensitivity. Here, we demonstrate that Protein Phosphatase 2A (PP2A) regulatory subunit B'κ constrains SIT1 activity under salt stress. B'κ-PP2A deactivates SIT1 directly by dephosphorylating the kinase at Thr515/516, a salt-induced phosphorylation site in the activation loop that is essential for SIT1 activity. B'κ overexpression suppresses the salt sensitivity of rice plants expressing high levels of SIT1, thereby contributing to salt tolerance. B'κ functions in a SIT1 kinase-dependent manner. During early salt stress, activated SIT1 phosphorylates B'κ; this not only enhances its binding with SIT1, it also promotes B'κ protein accumulation via Ser502 phosphorylation. Consequently, by blocking SIT1 phosphorylation, B'κ inhibits and fine-tunes SIT1 activity to balance plant growth and stress adaptation.


Asunto(s)
Oryza/metabolismo , Proteínas de Plantas/metabolismo , Proteínas Quinasas/metabolismo , Proteína Fosfatasa 2/metabolismo , Estrés Salino/fisiología , Adaptación Fisiológica , Regulación de la Expresión Génica de las Plantas , Oryza/genética , Oryza/crecimiento & desarrollo , Fosforilación , Proteínas de Plantas/genética , Raíces de Plantas/metabolismo , Plantas Modificadas Genéticamente , Estrés Salino/genética , Tolerancia a la Sal/genética , Tolerancia a la Sal/fisiología , Estrés Fisiológico
8.
Insect Sci ; 23(3): 452-68, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27060479

RESUMEN

MicroRNAs (miRNAs) are a novel class of small, non-coding endogenous RNAs that play critical regulatory roles in many metabolic activities in eukaryotes. Reports of the identification of miRNAs in Sogatella furcifera (white-backed planthopper), the insect that acts as the only confirmed vector of the southern rice black-streaked dwarf virus (SRBSDV), are limited. In this study, a total of 382 miRNAs were identified in S. furcifera, including 106 conserved and 276 novel miRNAs, using high-throughput sequencing based on two small RNA libraries from viruliferous and non-viruliferous S. furcifera, and these miRNAs belonged to 52 conserved miRNA families and 58 S. furcifera-specific families, respectively. Comparison with miRNAs from 26 insect species and five other species in miRBase showed that more than half of the conserved miRNA families are highly conserved in Hexapoda, while other miRNAs are only conserved in non-dipterans. Furthermore, 4 117 target genes predicted for the 382 identified miRNAs could be categorized into 45 functional groups annotated by Gene Ontology. Compared with non-viruliferous cells, eight up-regulated miRNAs and four down-regulated miRNAs were identified in cells inoculated with SRBSDV, among which miR-14 and miR-n98a may be involved in the immune response to SRBSDV infection. Analyses of the identified miRNAs will provide insights into the roles of these miRNAs in the regulation and expression of genes involved in the metabolism, development and viral infection of S. furcifera.


Asunto(s)
Hemípteros/genética , MicroARNs/aislamiento & purificación , Animales , Regulación de la Expresión Génica , Hemípteros/inmunología , Hemípteros/virología , Insectos Vectores/genética , Insectos Vectores/virología , Virus de Plantas/inmunología , Virus de Plantas/fisiología , Reoviridae/inmunología , Reoviridae/fisiología
9.
Hortic Res ; 3: 16007, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27004126

RESUMEN

The disease symptoms recognized as 'Anthracnose' are caused by Colletotrichum spp. and lead to large-scale strawberry (Fragaria×ananassa Duchesne) losses worldwide in terms of both quality and production. Little is known regarding the mechanisms underlying the genetic variations in the strawberry-Colletotrichum spp. interaction. In this work, Colletotrichum gloeosporioides (C. gloeosporioides) infection was characterized in two varieties exhibiting different susceptibilities, and the involvement of salicylic acid (SA) was examined. Light microscopic observation showed that C. gloeosporioides conidia germinated earlier and faster on the leaf surface of the susceptible cultivar compared with the less-susceptible cultivar. Several PR genes were differentially expressed, with higher-amplitude changes observed in the less-susceptible cultivar. The less-susceptible cultivar contained a higher level of basal SA, and the SA levels increased rapidly upon infection, followed by a sharp decrease before the necrotrophic phase. External SA pretreatment reduced susceptibility and elevated the internal SA levels in both varieties, which were sharply reduced in the susceptible cultivar upon inoculation. The less-susceptible cultivar also displayed a more sensitive and marked increase in the transcripts of NB-LRR genes to C. gloeosporioides, and SA pretreatment differentially induced transcript accumulation in the two varieties during infection. Furthermore, SA directly inhibited the germination of C. gloeosporioides conidia; NB-LRR transcript accumulation in response to SA pretreatment was both dose- and cultivar-dependent. The results demonstrate that the less-susceptible cultivar showed reduced conidia germination. The contribution of SA might involve microbial isolate-specific sensitivity to SA, cultivar/tissue-specific SA homeostasis and signaling, and the sensitivity of R genes and the related defense network to SA and pathogens.

10.
Zhongguo Zhong Yao Za Zhi ; 40(23): 4568-72, 2015 Dec.
Artículo en Chino | MEDLINE | ID: mdl-27141665

RESUMEN

Trans-cinnamaldehyde, the main component of volatile oil from cassia twig or Cinnamomum cassia, which is a traditional Chinese herbal medicine. Trans-cinnamaldehyde is a kind olefine aldehyde of organic compounds and has many pharmacological properties, such as anti-inflammatory, anti-tumor, anti-bacterial, antidiabetic, anti-obesity, and neuroprotection etc. The compound has preventive and therapeutic effects on the nervous system, cardiovascular, cancer, diabetes and other diseases. Trans-cinnamaldehyde, as a preventive care of nature medicine, has great clinical and market potential. This paper gives a review about the pharmacological effects and mechanism of trans-cinnamaldehyde researched in the latest five years. We hope to provide some basic information for further research on trans-cinnamaldehyde.


Asunto(s)
Acroleína/análogos & derivados , Cinnamomum aromaticum/química , Medicamentos Herbarios Chinos/farmacología , Acroleína/química , Acroleína/farmacología , Animales , Medicamentos Herbarios Chinos/química , Humanos
11.
Plant Cell ; 26(6): 2538-2553, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24907341

RESUMEN

High salinity causes growth inhibition and shoot bleaching in plants that do not tolerate high salt (glycophytes), including most crops. The molecules affected directly by salt and linking the extracellular stimulus to intracellular responses remain largely unknown. Here, we demonstrate that rice (Oryza sativa) Salt Intolerance 1 (SIT1), a lectin receptor-like kinase expressed mainly in root epidermal cells, mediates salt sensitivity. NaCl rapidly activates SIT1, and in the presence of salt, as SIT1 kinase activity increased, plant survival decreased. Rice MPK3 and MPK6 function as the downstream effectors of SIT1. SIT1 phosphorylates MPK3 and 6, and their activation by salt requires SIT1. SIT1 mediates ethylene production and salt-induced ethylene signaling. SIT1 promotes accumulation of reactive oxygen species (ROS), leading to growth inhibition and plant death under salt stress, which occurred in an MPK3/6- and ethylene signaling-dependent manner in Arabidopsis thaliana. Our findings demonstrate the existence of a SIT1-MPK3/6 cascade that mediates salt sensitivity by affecting ROS and ethylene homeostasis and signaling. These results provide important information for engineering salt-tolerant crops.

12.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 34(2): 179-84, 2014 Feb.
Artículo en Chino | MEDLINE | ID: mdl-24672942

RESUMEN

OBJECTIVE: To explore the potential effect of Guizhi plus Gegen Decoction (GGD) in improving learning and memory of lipopolysaccharides (LPS) induced neuroinflammatory mice and its possible mechanisms. METHODS: Totally 63 male ICR mice were randomly divided into 5 groups, i.e., the normal control (n = 13), the model group (n = 13), the low dose GGD group (n = 10), the high dose GGD group (n = 14), and the positive control group (n = 13). Mice were intraperitoneally injected with LPS (0.33 mg/kg) to induce Alzheimer's disease (AD) model. Mice in the high and the low dose GGD groups were administered with 12 g/kg or 6 g/kg by gastrogavage for 4 successive weeks. Mice in the control group were intraperitoneally injected with minocycline (50 mg/kg) for 3 days. By the end of treatment LPS were injected 4 h before behavior test each day, and then behavior test was conducted in mice of each group. Effect of GGD on learning and memory of AD mice was observed by using open field test, novel object recognition task, and Morris water maze. RESULTS: Open field test showed there was no statistical difference in the movement time and the movement distance among all groups (P > 0.05), suggesting that LPS and GGD had no effect on locomotor activities of mice. In novel object recognition test, AD mice spent significantly shorter time to explore novel object after they were induced by LPS (P < 0.05), while for AD mice in the low and high dose GGD groups, their capacities for exploration and memory were significantly improved (P < 0. 05, P < 0.01). Results of Morris water maze showed that AD mice exhibited increased escape latency (P < 0.05) and spent much less time in swimming across the original platform (both P < 0.05). However, AD mice in the low and high dose GGD groups had obvious shortened latency and increased time percentage for swimming (P < 0.05, P < 0.01). CONCLUSION: GGD possessed certain improvement in learning and memory disorder of LPS induced AD mice.


Asunto(s)
Medicamentos Herbarios Chinos/uso terapéutico , Neuritis/tratamiento farmacológico , Neuritis/psicología , Enfermedad de Alzheimer/inducido químicamente , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/psicología , Animales , Lipopolisacáridos/efectos adversos , Masculino , Trastornos de la Memoria/prevención & control , Ratones , Ratones Endogámicos ICR , Neuritis/inducido químicamente , Fitoterapia
13.
Pak J Pharm Sci ; 26(1): 1-6, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23261720

RESUMEN

Sarcandra glaber is a common traditional Chinese medicine used to treat psoriasis and other infectious diseases, isofraxidin and astilbin are the main components of it. In order to study the pharmacokinetics of Sarcandra glabra, an HPLC method for simultaneous determination of isofraxidin and astilbin in rat plasma was established. Plasma samples were prepared using solid phase extraction method. C(18) column with a guard was used, mobile phase was consisted of A (methanol) and B (0.1% aqueous acetic acid) with gradient elution as follows: 0 - 4min, A: 35%, B: 65%; 4 - 10min, A: 35% - 45%, B: 65% - 55%; 10 - 20min, A: 45%, B: 55%. The flow rate was 1.2 mL/min from 0 to 4 min, 1.0 mL/min from 4 to 20 min. The detection wavelength was 300 nm. A linear correlation between drug amount and peak area was established for isofraxidin in the range of 20-320 ng and for astilbin in the range of 19-304 ng. The recovery was over 68% for both compounds, the accuracy was within 8%, and the inter-day and intra-day precisions were all less than 8%. The pharmacokinetics of isofraxidin and astilbin was studied after orally administration the extract of Sarcandra glabra.


Asunto(s)
Cromatografía Líquida de Alta Presión , Cumarinas/administración & dosificación , Cumarinas/sangre , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/metabolismo , Flavonoles/administración & dosificación , Flavonoles/sangre , Magnoliopsida , Administración Oral , Animales , Calibración , Cromatografía Líquida de Alta Presión/normas , Cumarinas/farmacocinética , Medicamentos Herbarios Chinos/farmacocinética , Flavonoles/farmacocinética , Modelos Lineales , Masculino , Tasa de Depuración Metabólica , Plantas Medicinales , Ratas , Ratas Wistar , Estándares de Referencia , Reproducibilidad de los Resultados
14.
Appl Microbiol Biotechnol ; 95(6): 1469-78, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22215071

RESUMEN

Cellulases can be engineered with enhanced properties for broad use in scientific and industrial applications. In this study, the wild-type cbh2 gene of the thermophilic fungus Chaetomium thermophilum encoding cellobiohydrolase II (CBHII) was mutagenized through in vitro directed evolution. The resulting Pichia pastoris yeast library was screened, and two transformants were selected for enhanced CBHII activities that were not attributed to increased gene copy numbers. The optimum fermentation times of the two mutant transformants were shortened to 4-5 days after methanol induction compared to 6 days for the wild-type. The optimum reaction temperature (60 °C) and pH level (5 or 6) of the mutant CBHII proteins, designated CBHIIX16 and CBHIIX305, were higher than those of wild-type CBHII (50 °C and pH 4). Kept at 80 °C for 1 h, CBHIIX16 and CBHIIX305 retained >50% of their activities, while the wild-type CBHII lost all activity. Sequence analysis of CBHIIX16 and CBHIIX305 revealed that they contained five and six mutated amino acids, respectively. Structural modeling confirmed the presence of carbohydrate binding type-1 and catalytic domains, where the hydrogen bond numbers between the 227th and 203rd amino acids were increased, which perhaps contributed to the elevated enzyme stability. Therefore, the two CBHII mutants selected for increased enzymatic activities also demonstrated elevated optimum reaction temperature and pH levels and enhanced thermal stability. These properties may be beneficial in practical applications for CBHII.


Asunto(s)
Celulosa 1,4-beta-Celobiosidasa/química , Celulosa 1,4-beta-Celobiosidasa/genética , Chaetomium/enzimología , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Secuencia de Aminoácidos , Celulosa 1,4-beta-Celobiosidasa/metabolismo , Chaetomium/química , Chaetomium/genética , Clonación Molecular , Evolución Molecular Dirigida , Estabilidad de Enzimas , Fermentación , Proteínas Fúngicas/metabolismo , Calor , Concentración de Iones de Hidrógeno , Cinética , Datos de Secuencia Molecular , Pichia/genética , Pichia/metabolismo , Conformación Proteica
15.
Amino Acids ; 42(4): 1309-16, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21191803

RESUMEN

Due to the complexity of Plasmodium falciparum (PF) genome, predicting mitochondrial proteins of PF is more difficult than other species. In this study, using the n-peptide composition of reduced amino acid alphabet (RAAA) obtained from structural alphabet named Protein Blocks as feature parameter, the increment of diversity (ID) is firstly developed to predict mitochondrial proteins. By choosing the 1-peptide compositions on the N-terminal regions with 20 residues as the only input vector, the prediction performance achieves 86.86% accuracy with 0.69 Mathew's correlation coefficient (MCC) by the jackknife test. Moreover, by combining with the hydropathy distribution along protein sequence and several reduced amino acid alphabets, we achieved maximum MCC 0.82 with accuracy 92% in the jackknife test by using the developed ID model. When evaluating on an independent dataset our method performs better than existing methods. The results indicate that the ID is a simple and efficient prediction method for mitochondrial proteins of malaria parasite.


Asunto(s)
Biología Computacional/métodos , Proteínas Mitocondriales/química , Plasmodium falciparum/química , Proteínas Protozoarias/química , Proteínas Protozoarias/genética , Secuencia de Aminoácidos , Bases de Datos de Proteínas , Proteínas Mitocondriales/genética , Datos de Secuencia Molecular , Plasmodium falciparum/genética , Análisis de Secuencia de Proteína
16.
J Bacteriol ; 193(16): 4261-2, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21685279

RESUMEN

Ralstonia solanacearum strain Po82, a phylotype IIB/sequevar 4 strain, was found to be pathogenic to both solanaceous plants and banana. Here, we report the complete genome sequence of Po82 and its comparison with seven published R. solanacearum genomes.


Asunto(s)
Genoma Bacteriano , Enfermedades de las Plantas/microbiología , Ralstonia solanacearum/clasificación , Ralstonia solanacearum/genética , Secuencia de Bases , Anotación de Secuencia Molecular , Datos de Secuencia Molecular
17.
Biotechnol Lett ; 33(6): 1127-32, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21287231

RESUMEN

A new superoxide dismutase (SOD) gene from the thermophilic fungus Chaetomium thermophilum (Ctsod) was cloned and expressed in Pichia pastoris and its gene product was characterized. The specific activity of the purified CtSOD was 2,170 U/mg protein. The enzyme was inactivated by KCN and H(2)O(2) but not by NaN(3), confirming that it belonged to the type of Cu, ZnSOD. The amino acid residues involved in coordinating copper and zinc were conserved. The recombinant CtSOD exhibited optimum activity at pH 6.5 and 60°C. The enzyme retained 65% of the maximum activity at 70°C for 60 min and the half-life was 22 and 7 min at 80 and 90°C, respectively. The recombinant yeast exhibited higher stress resistance than the control yeast cells to salt and superoxide-generating agents, such as paraquat and menadione.


Asunto(s)
Chaetomium/enzimología , Chaetomium/genética , Pichia/enzimología , Pichia/genética , Superóxido Dismutasa/genética , Superóxido Dismutasa/metabolismo , Antioxidantes/metabolismo , Secuencia de Bases , Biotecnología , Clonación Molecular , ADN de Hongos/genética , Inhibidores Enzimáticos/farmacología , Estabilidad de Enzimas , Proteínas Fúngicas/antagonistas & inhibidores , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Expresión Génica , Genes Fúngicos , Estrés Oxidativo , Proteínas Recombinantes/antagonistas & inhibidores , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Salinidad , Superóxido Dismutasa/antagonistas & inhibidores
18.
Acta Crystallogr Sect F Struct Biol Cryst Commun ; 66(Pt 9): 1089-92, 2010 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-20823534

RESUMEN

Cu,Zn superoxide dismutase (Cu,ZnSOD) from the thermophilic fungus Chaetomium thermophilum was expressed in Pichia pastoris and purified. Crystals were grown in over 120 conditions but only those produced with 1.4 M sodium potassium phosphate pH 8.2 as precipitant were suitable for structural studies. Data were collected to 1.9 A resolution at 100 K from a single crystal using a synchrotron-radiation source. The crystals belonged to space group P6(1)/P6(5), with unit-cell parameters a=90.2, c=314.5 A and eight molecules in the asymmetric unit. Elucidation of the crystal structure will provide insights into the active site of the enzyme and a better understanding of the structure-activity relationship, assembly and thermal stability of Cu,ZnSODs.


Asunto(s)
Chaetomium/enzimología , Superóxido Dismutasa/química , Cristalización , Cristalografía por Rayos X , Expresión Génica , Superóxido Dismutasa/genética , Superóxido Dismutasa/aislamiento & purificación
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(4): 949-52, 2010 Apr.
Artículo en Chino | MEDLINE | ID: mdl-20545137

RESUMEN

Successive projections algorithm combined with partial least squares regression, termed as SPA-PLS approach, was implemented as a novel variable selection approach to multivariate calibration. The proposed approach was applied to near-infrared reflectance data for analyzing moisture in wheat. The number of variables selected from 701 spectral variables was reduced to 16 by SPA, and the root mean squared error of prediction set (RMSEP) of the corresponding partial least squares regression models was decreased to 0.205 5% as well. The result indicates that the SPA-PLS approach by performing SPA prior to calibration not only can improve the model accuracy, but also decreases the number of spectral variables, so its resulting model becomes more concise. Moreover, as compared with genetic algorithm for wavelength selection, SPA is a deterministic search technique whose results are reproducible and it is more robust with respect to the choice of the validation set.


Asunto(s)
Algoritmos , Espectroscopía Infrarroja Corta , Triticum , Calibración , Análisis de los Mínimos Cuadrados , Análisis de Regresión
20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(4): 860-4, 2008 Apr.
Artículo en Chino | MEDLINE | ID: mdl-18619316

RESUMEN

Electronic absorption spectroscopy (EAS), as an indirect analytical technique, has been used to carry out quantitative analysis of unknown samples by establishing a model with calibration samples. Partial least squares (PLS), as a powerful technique for process modeling and multivariate statistical process control, has been widely used to establish this model. On account of the noise signal in the spectra, the signal preprocessing was often a necessary step in building reliable and robust multivariate calibrations. The main goal of preprocessing was to remove variation in the data that was irrelevant to modeling. Orthogonal signal correction (OSC) and related methods emerged as filtering techniques for various spectra in modern chemometrics literature. However, it was confirmed in recent work that preprocessing with OSC did not lead to any significant improvements in calibration models subsequently developed by means of PLS regression, except for merely reducing the number of latent variables in the PLS model by the number of OSC components removed. Now in our study, taking into account the local effect sensitivity and numerous predictor variables with serious multicollinearity of the spectra data, a novel PLS algorithm that embedded the OSC into the regression framework of the PLS, termed as POSC-PLS method, was implemented. It firstly applied the OSC technique to a set of selected spectra at an optimized size of moving window, namely piecewise OSC (POSC), to pretreat the spectra matrix and eliminate the local variance, thus the spectra matrix pretreated was taken as the new independent variables matrix, then the PLS algorithm was applied to build the calibration model. Finally, application of the proposed POSC-PLS approach to the EAS quantitative analysis of the polyaromatic hydrocarbons (PAHs)was presented for comparison with the MLR (multiple linear regression), PLS and OSC-PLS methods. The result indicates that the POSC-PLS approach by performing POSC prior to calibration not only can improve the model accuracy, but also decreases the PLS factors compared to the models obtained by the above rest methods and so its resulting model becomes more concise. The removal of orthogonal components from the response matrix is greatly facilitated simply by considering localized spectral features. So, preprocessing with POSC was shown to benefit the multivariate PLS model because it performed a localized regression modeling procedure that differs from that of PLS. At the same time, the POSC is a potential chemometric technique in the pretreatment of various spectra.


Asunto(s)
Espectrofotometría/métodos , Calibración , Análisis de los Mínimos Cuadrados
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