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1.
J Orthop Surg Res ; 18(1): 789, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37864189

RESUMO

INTRODUCTION: Intervertebral disk degeneration (IVDD) can be effectively treated using platelet-rich plasma (PRP). While the exact process is fully understood, it is believed that using pure PRP (P-PRP) without leukocytes is a better option for preventing IVDD. Semaphorin-3A (Sema3A), an inhibitor of angiogenesis and innervation, is essential for preserving IVDD's homeostasis. Whether PRP prevents IVDD by modifying Sema3A has yet to receive much research. This work aims to clarify how P-PRP affects Sema3A when IVDD develops in vitro. METHODS: Nucleus pulposus cells (NPCs) isolated from 8-week-old male Sprague-Dawley rats were exposed to 10 ng/ml IL-1ß and then treated with P-PRP or leukocyte platelet-rich plasma (L-PRP) in vitro, followed by measuring cell proliferation, apoptosis and microstructures, inflammatory gene and Sema3A expression, as well as anabolic and catabolic protein expression by immunostaining, quantitative real-time polymerase chain reaction (qPCR), western blot, and enzyme-linked immunosorbent assay (ELISA). RESULTS: In comparison with L-PRP, P-PRP had a higher concentration of growth factors but a lower concentration of inflammatory substances. P-PRP increased the proliferation of NPCs, while IL-1 relieved the amount of apoptosis due to its intervention. Anabolic genes, aggrecan, and collagen II had higher expression levels. MMP-3 and ADAMTS-4, two catabolic or inflammatory genes, showed lower expression levels. Sema3A activity was enhanced after P-PRP injection, whereas CD31 and NF200 expression levels were suppressed. CONCLUSIONS: P-PRP enhanced the performance of NPCs in IVDD by modifying the NF-κB signaling pathway and encouraging Sema3A expression, which may offer new therapy options for IVDD. THE TRANSLATIONAL POTENTIAL OF THIS ARTICLE: The findings provide a new therapeutic target for the treatment of IVDD and show a novel light on the probable mechanism of PRP and the function of Sema3A in the progression of IVDD.


Assuntos
Degeneração do Disco Intervertebral , Plasma Rico em Plaquetas , Animais , Masculino , Ratos , Colágeno/metabolismo , Degeneração do Disco Intervertebral/terapia , Degeneração do Disco Intervertebral/metabolismo , Plasma Rico em Plaquetas/metabolismo , Ratos Sprague-Dawley , Semaforina-3A/análise , Semaforina-3A/metabolismo
2.
Front Aging Neurosci ; 13: 741445, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34675799

RESUMO

Aneurysmal subarachnoid hemorrhage (aSAH) is a common disease causing vascular dementia. Survivors often suffer from cognitive impairment especially working memory deficit. Currently, lack of theoretical support limits the improvement of cognitive intervention or rehabilitation. It is unclear how the large-scale network differs and to what extent is the brain network affected? Our study aims to provide novel information about the topological characteristics of brain organization, especially "small-world" property. A total of 62 aSAH patients are enrolled in this study. They are divided into two groups according to the syndrome of working memory deficit. Their working memory function is evaluated by TMT-B and AVLT (Chinese version). Functional MRI scan is also performed for detecting resting-state cortical plasticity. We utilized ICA to extract functional sub-networks including working memory network from imaging data. And then we establish binarized network and calculate the small-worldness property as well as local and global efficiency of networks. aSAH group with working memory deficit shows no significant difference of clustering coefficient with control group. Our study discovered significant decrease of characteristic path length indicating an increase of overall routing efficiency. We reason that patients with working memory deficit have to recruit more neuronal resources and thus develops higher overall routing efficiency of local network. This study provides novel information about the neural alterations of aSAH patients with working memory deficit. It might contribute to the understanding of neural mechanism and the improvement of current intervention for vascular dementia.

3.
Environ Microbiol ; 22(3): 1125-1140, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31858668

RESUMO

Bacillus thuringiensis is the most widely used eco-friendly biopesticide, containing two primary determinants of biocontrol, endospore and insecticidal crystal proteins (ICPs). The 2-methylcitrate cycle is a widespread carbon metabolic pathway playing a crucial role in channelling propionyl-CoA, but with poorly understood metabolic regulatory mechanisms. Here, we dissect the transcriptional regulation of the 2-methylcitrate cycle operon prpCDB and report its unprecedented role in controlling the sporulation process of B. thuringiensis. We found that the transcriptional activity of the prp operon encoding the three critical enzymes PrpC, PrpD, and PrpB in the 2-methylcitrate cycle was negatively regulated by the two global transcription factors CcpA and AbrB, while positively regulated by the LysR family regulator CcpC, which jointly account for the fact that the 2-methylcitrate cycle is specifically and highly active in the stationary phase of growth. We also found that the prpD mutant accumulated 2-methylcitrate, the intermediate metabolite of the 2-methylcitrate cycle, which delayed and inhibited sporulation at the early stage. Thus, our results not only revealed sophisticated transcriptional regulatory mechanisms for the metabolic 2-methylcitrate cycle but also identified 2-methylcitrate as a novel regulator of sporulation in B. thuringiensis.


Assuntos
Bacillus thuringiensis/crescimento & desenvolvimento , Bacillus thuringiensis/genética , Proteínas de Bactérias/genética , Citratos/metabolismo , Regulação Bacteriana da Expressão Gênica/genética , Hidroliases/genética , Esporos Bacterianos/genética , Acil Coenzima A/metabolismo , Bacillus thuringiensis/enzimologia , Proteínas de Bactérias/metabolismo , Redes e Vias Metabólicas/genética , Óperon/genética , Esporos Bacterianos/crescimento & desenvolvimento , Fatores de Transcrição/genética
4.
Zhongguo Gu Shang ; 32(10): 941-946, 2019 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-32512967

RESUMO

OBJECTIVE: To explore the feasibility of full endoscopic fenestration (FE-FE) via interlaminar approach for the treatment of lumbar spinal stenosis (LSS), and meanwhile, to analyze the related practicability and clinical outcome. METHODS: Referring to the traditional laminectomy and decompression, the lumbar spinal canal decompression was performed by using the water-medium spinal endoscopy (named FE-FE technique). Thirty-seven patients with LSS treated by FE-FE technique were retrospectively analyzed. There were 19 males and 18 females, aged from 55 to 83 years old with an average of (67.1±18.9) years. Visual analogue scale(VAS), Japanese Orthopaedic Association Scores(JOA), Oswestry Disability Index (ODI) and 36-Item Short-Form Health Survey (SF-36) were recorded. The patient's conscious pain and recovery of neurological function were observed, and the clinical efficacy was evaluated according to the improvement rate of JOA score. RESULTS: All 37 patients were followed up for 8 to 24 months with an average of (13.7±6.1) months. The postoperative follow-up and clinical evaluation for conscious pain and neurological function recovery showed that VAS, JOA, ODI and SF-36 scores were significantly improved compared with those before surgery(P<0.05). According to the improvement rate of JOA score to evaluate the clinical effects, at 6 months after opertion, the results were excellent in 17 cases, good in 13 cases, fair in 5 cases, and poor in 2 cases;and the last follow-up, the results were excellent in 19 cases, good in 13 cases, fair in 4 cases, and poor in 1 case. Postoperative imaging showed significant expansion of spine canal volume, and the followed-up clinical symptoms were improved satisfactorily, with the relief of lumbago and leg pain, improvement of daily life quality, and increased adaptability to social activities and no serious complications. CONCLUSIONS: Precise localization is the key to complete the canal decompression under full endoscopic surgery. FE-FE technique can effectively enlarge the narrow lumbar canal with less trauma, positive efficacy, safety and reliability. FE-FE has a broad application prospect though large cases and multi-center studies need to be further carried out.


Assuntos
Estenose Espinal , Idoso , Idoso de 80 Anos ou mais , Descompressão Cirúrgica , Feminino , Humanos , Laminectomia , Vértebras Lombares , Masculino , Pessoa de Meia-Idade , Neuroendoscopia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Estenose Espinal/cirurgia , Resultado do Tratamento
5.
Sci Rep ; 8(1): 13352, 2018 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-30190566

RESUMO

The differences in artificial and natural selection have been some of the factors contributing to phenotypic diversity between Chinese and western pigs. Here, 830 individuals from western and Chinese pig breeds were genotyped using the reduced-representation genotyping method. First, we identified the selection signatures for different pig breeds. By comparing Chinese pigs and western pigs along the first principal component, the growth gene IGF1R; the immune genes IL1R1, IL1RL1, DUSP10, RAC3 and SWAP70; the meat quality-related gene SNORA50 and the olfactory gene OR1F1 were identified as candidate differentiated targets. Further, along a principal component separating Pudong White pigs from others, a potential causal gene for coat colour (EDNRB) was discovered. In addition, the divergent signatures evaluated by Fst within Chinese pig breeds found genes associated with the phenotypic features of coat colour, meat quality and feed efficiency among these indigenous pigs. Second, admixture and genomic introgression analysis were performed. Shan pigs have introgressed genes from Berkshire, Yorkshire and Hongdenglong pigs. The results of introgression mapping showed that this introgression conferred adaption to the local environment and coat colour of Chinese pigs and the superior productivity of western pigs.


Assuntos
Cruzamento , Genoma , Suínos/genética , Animais , China , Feminino , Masculino , Especificidade da Espécie
6.
Lab Chip ; 18(9): 1330-1340, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29619469

RESUMO

Microfluidic droplets have been applied extensively as reaction vessels in a wide variety of chemical and biological applications. Typically, once the droplets are formed in a flow channel, it is a challenge to add new chemicals to the droplets for subsequent reactions in applications involving multiple processing steps. Here, we present a novel and versatile method that employs a high strength alternating electrical field to tunably transfer chemicals into microfluidic droplets using nanodroplets as chemical carriers. We show that the use of both continuous and cyclic burst square wave signals enables extremely sensitive control over the total amount of chemical added and, equally importantly, the rate of addition of the chemical from the nanodroplet carriers to the microfluidic droplets. An a priori theoretical model was developed to model the mass transport process under the convection-controlled scenario and compared with experimental results. We demonstrate an application of this method in the controlled preparation of gold nanoparticles by reducing chloroauric acid pre-loaded in microfluidic droplets with l-ascorbic acid supplied from miniemulsion nanodroplets. Under different field strengths, l-ascorbic acid is supplied in controllable quantities and addition rates, rendering the particle size and size distribution tunable. Finally, this method also enables multistep synthesis by the stepwise supply of miniemulsions containing different chemical species. We highlight this with a first report of a three-step Au-Pd core-shell nanoparticle synthesis under continuous flow conditions.


Assuntos
Nanopartículas Metálicas/química , Microfluídica/métodos , Nanotecnologia/métodos , Eletricidade , Emulsões , Ouro/química , Modelos Teóricos , Tamanho da Partícula
7.
Sci Rep ; 6: 37608, 2016 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-27869185

RESUMO

This study proposes a new method for removal of metal artifacts from megavoltage cone beam computed tomography (MVCBCT) and kilovoltage CT (kVCT) images. Both images were combined to obtain prior image, which was forward projected to obtain surrogate data and replace metal trace in the uncorrected kVCT image. The corrected image was then reconstructed through filtered back projection. A similar radiotherapy plan was designed using the theoretical CT image, the uncorrected kVCT image, and the corrected image. The corrected images removed most metal artifacts, and the CT values were accurate. The corrected image also distinguished the hollow circular hole at the center of the metal. The uncorrected kVCT image did not display the internal structure of the metal, and the hole was misclassified as metal portion. Dose distribution calculated based on the corrected image was similar to that based on the theoretical CT image. The calculated dose distribution also evidently differed between the uncorrected kVCT image and the theoretical CT image. The use of the combined kVCT and MVCBCT to obtain the prior image can distinctly improve the quality of CT images containing large metal implants.


Assuntos
Artefatos , Tomografia Computadorizada de Feixe Cônico/métodos , Metais/química , Tomografia Computadorizada por Raios X/métodos , Relação Dose-Resposta à Radiação , Humanos , Imagens de Fantasmas , Interpretação de Imagem Radiográfica Assistida por Computador
8.
Bioresour Technol ; 221: 405-411, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27660991

RESUMO

Schizochytrium sp. is a hopeful docosahexaenoic acid (DHA) producing candidate due to its rapid growth rate and high DHA proportion in total lipid content. In this study, low-energy ion implantation was applied to Schizochytrium sp. to induce high DHA-producing mutants. Screening these mutants by Sudan black B staining, a mutant strain S1 which showed a 61% improvement in DHA production than that of the parent strain was successfully selected. Subsequently, parameters of DHA production of mutant strain S1 were optimized in a 500-mL Erlenmeyer flask. Under the optimum fermentation conditions, the production of DHA and the percentage of DHA in total lipid of mutant strain S1 were 6.52g/L and 46.2%, respectively. This study provides an effective breeding strategy for improved DHA production of Schizochytrium sp. through combination of the novel mutagenesis technology, the effective screening method and fermentation optimization.


Assuntos
Ácidos Docosa-Hexaenoicos/biossíntese , Estramenópilas/crescimento & desenvolvimento , Estramenópilas/metabolismo , Compostos Azo , Fermentação , Mutagênese , Naftalenos , Coloração e Rotulagem
9.
Sci Rep ; 6: 20871, 2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26892868

RESUMO

c-di-GMP riboswitches are structured RNAs located in the 5'-untranslated regions (5'-UTRs) of mRNAs that regulate expression of downstream genes in response to changing concentrations of the second messenger c-di-GMP. We discovered three complete c-di-GMP riboswitches (Bc3, Bc4 and Bc5 RNA) with similar structures, which are arranged in tandem to constitute a triple-tandem (Bc3-5 RNA) riboswitch in the 5'-UTR of the cspABCDE mRNA in Bacillus thuringiensis subsp. chinensis CT-43. Our results showed that this natural triple-tandem riboswitch controlled the expression of the reporter gene more stringently and digitally than the double-tandem or single riboswitch. A sandwich-like dual-fluorescence reporter was further constructed by fusing the Bc3-5 RNA gene between the two fluorescence protein genes amcyan and turborfp. This reporter strain was found to exhibit detectable fluorescence color changes under bright field in response to intracellular c-di-GMP level altered by induced expression of diguanylate cyclase (DGC) PleD. Using this system, two putative membrane-bound DGCs from B. thuringiensis and Xanthomonas oryzae were verified to be functional by replacing pleD with the corresponding DGC genes. This report represented the first native triple-tandem riboswitch that was applied to serve as a riboswitch-based dual-fluorescence reporter for the efficient and convenient verification of putative DGC activity in vivo.


Assuntos
GMP Cíclico/análogos & derivados , Regulação da Expressão Gênica , Genes Reporter , Riboswitch , Sequência de Bases , Biologia Computacional/métodos , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Conformação de Ácido Nucleico , RNA Mensageiro/química , RNA Mensageiro/genética
10.
Biotechnol Lett ; 38(3): 377-84, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26564407

RESUMO

OBJECTIVES: To investigate the effect of the combination of LMP-1 and HIF-1α delivered by adipose-derived stem cells (ADSCs) on osteogenesis in vitro and in vivo. RESULTS: Cells expressing both LMP-1 and HIF-1α genes had elevated mRNA expression of BMP-2, RunX2, alkaline phosphatase, osteocalcin, collagen I and alkaline phosphatase activity compared to cells from other groups. Furthermore, mineralization at day 14 in the cells expressing both LMP-1 and HIF-1α was significantly higher than in all the other groups. In vivo, H&E staining and immunohistochemical analysis of the cell-scaffolds also showed more ectopic bone formation at 4 weeks compared to other groups. More new vessel formation was apparent in the pLVX-rHIF-1α and pLVX-rLMP-1-rHIF-1α groups. CONCLUSION: LMP-1 and HIF-1α gene delivery synergistically enhanced the osteo-differentiation of ADSCs in vitro and promoted osteogenesis in vivo compared with LMP-1 alone or HIF-1α alone.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Regeneração Óssea/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proteínas do Citoesqueleto/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteínas com Domínio LIM/metabolismo , Células-Tronco/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Proteínas do Citoesqueleto/genética , Células HEK293 , Histocitoquímica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Imuno-Histoquímica , Proteínas com Domínio LIM/genética , Camundongos , Osteogênese/efeitos dos fármacos
11.
Front Microbiol ; 6: 908, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26441857

RESUMO

Cyclic di-AMP (c-di-AMP) is a recently discovered bacterial secondary messenger molecule, which is associated with various physiological functions. In the genus Bacillus, the intracellular level and turnover of c-di-AMP are mainly regulated by three diadenylate cyclases (DACs), including DisA, CdaA and CdaS, and two c-di-AMP-specific phosphodiesterases (GdpP and PgpH). In this study, we demonstrated that CdaS protein from B. thuringiensis is a hexameric DAC protein that can convert ATP or ADP to c-di-AMP in vitro and the N-terminal YojJ domain is essential for the DAC activity. Based on the markerless gene knock-out method, we demonstrated that the transcription of cdaS was initiated by the sporulation-specific sigma factor σ(H) and the deletion of cdaS significantly delayed sporulation and parasporal crystal formation. These findings contrast with similar experiments conducted using B. subtilis, wherein transcription of its cdaS was initiated by the sigma factor σ(G). Deletion of all the three DAC genes from a single strain was unsuccessful, suggesting that c-di-AMP is an indispensable molecule in B. thuringiensis. Phylogenetic analysis indicated increased diversity of CdaS in the B. cereus and B. subtilis Bacillus subgroups. In summary, this study identifies important aspects in the regulation of c-di-AMP in the genus Bacillus.

12.
Int J Biol Sci ; 11(7): 813-24, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26078723

RESUMO

Cyclic di­AMP (c-di-AMP) is a second signaling molecule involved in the regulation of bacterial physiological processes and interaction between pathogen and host. However, the regulatory network mediated by c-di-AMP in Mycobacterium remains obscure. In M. smegmatis, a diadenylate cyclase (DAC) was reported recently, but there is still no investigation on c-di-AMP phosphodiesterase (PDE). Here, we provide a systematic study on signaling mechanism of c-di-AMP PDE in M. smegmatis. Based on our enzymatic analysis, MsPDE (MSMEG_2630), which contained a DHH-DHHA1 domain, displayed a 200-fold higher hydrolytic efficiency (kcat /Km ) to c-di-AMP than to c-di-GMP. MsPDE was capable of converting c-di-AMP to pApA and AMP, and hydrolyzing pApA to AMP. Site-directed mutations in DHH and DHHA1 revealed that DHH domain was critical for the phosphodiesterase activity. To explore the regulatory role of c-di-AMP in vivo, we constructed the mspde mutant (Δmspde) and found that deficiency of MsPDE significantly enhanced intracellular C12-C20 fatty acid accumulation. Deficiency of DAC in many bacteria results in cell death. However, we acquired the M. smegmatis strain with DAC gene disrupted (ΔmsdisA) by homologous recombination approach. Deletion of msdisA reduced bacterial C12-C20 fatty acids production but scarcely affected bacterial survival. We also provided evidences that superfluous c-di-AMP in M. smegmatis could lead to abnormal colonial morphology. Collectively, our results indicate that MsPDE is a functional c-di-AMP-specific phosphodiesterase both in vitro and in vivo. Our study also expands the regulatory network mediated by c-di-AMP in M. smegmatis.


Assuntos
Fosfatos de Dinucleosídeos/metabolismo , Redes Reguladoras de Genes/genética , Mycobacterium smegmatis/enzimologia , Diester Fosfórico Hidrolases/metabolismo , Transdução de Sinais/genética , Adenilil Ciclases/metabolismo , Cromatografia Gasosa , Cromatografia Líquida , Escherichia coli , Ácidos Graxos/metabolismo , Hidrólise , Mutagênese Sítio-Dirigida , Diester Fosfórico Hidrolases/genética , Estrutura Terciária de Proteína , Espectrometria de Massas em Tandem
13.
J Vet Med Sci ; 75(10): 1393-8, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23728200

RESUMO

The aim of this study was to evaluate MHC class I expression and prognosis using tumor tissues surgically removed from 9 dogs with mammary gland carcinomas and from 13 dogs with complex carcinomas. We assessed MHC class I expression and its correlation with tumor size, B2M expression, infiltration of lymphocytes, histological grade and prognosis. Hematoxylin and eosin-stained sections were histologically graded using the Elston and Ellis grading method. MHC class I expression on tumor cells was evaluated using the avidin-biotin peroxidase complex method. Loss of MHC class I expression from canine mammary gland carcinomas was significantly correlated with poor prognosis (P<0.05). Loss of MHC class I expression showed no association with poor prognosis in canine mammary gland complex carcinomas, because the data were not balanced. Only 1 of 13 (7.6%) canine mammary gland complex carcinomas showed loss of MHC class I expression. All 13 of these dogs showed good prognosis. Thus, the low frequency of MHC class I expression loss from canine mammary gland complex carcinomas may be associated with good prognosis. Taken together, these results suggest that loss of MHC class I expression may be associated with poor prognosis in canine mammary gland carcinomas.


Assuntos
Doenças do Cão/patologia , Regulação Neoplásica da Expressão Gênica/genética , Antígenos de Histocompatibilidade Classe I/genética , Neoplasias Mamárias Animais/patologia , Animais , Doenças do Cão/genética , Doenças do Cão/cirurgia , Cães , Feminino , Imuno-Histoquímica/veterinária , Neoplasias Mamárias Animais/genética , Neoplasias Mamárias Animais/cirurgia , Prognóstico , Análise de Sobrevida , Microglobulina beta-2/genética
14.
Enzyme Microb Technol ; 52(6-7): 319-24, 2013 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-23608499

RESUMO

Cyclic 3',5'-diadenosine monophosphate (c-di-AMP) is a newly recognized bacterial nucleotide second messenger molecule. In addition, it has been shown to be a potential vaccine adjuvant. Although multiple methods are available for c-di-AMP synthesis, the yields are low and the purification procedures are laborious. Here, we report an enzymatic method for more efficient and economical c-di-AMP synthesis using a diadenylate cyclase DisA from Bacillus thuringiensis BMB 171 (btDisA). After overexpression and purification of btDisA, the enzyme-catalyzed reaction conditions were further investigated. Under the optimum conditions, in which 100mM CHES (pH 9.5) containing 2µM btDisA, 10mM ATP, and 10mM MgCl2 was incubated at 50°C for 4h, a high conversion rate of c-di-AMP was obtained. Coupling this process with HPLC purification and lyophilization yielded 100mg of highly pure c-di-AMP that was harvested in white powder form from a 50mL enzyme-catalyzed reaction system. The protocol is not only directly applicable for preparing abundant amounts of c-di-AMP for extensive biochemical and immunological use, but can also be scaled up to meet the requirements for medical applications.


Assuntos
Bacillus thuringiensis/enzimologia , Fosfatos de Dinucleosídeos/biossíntese , Microbiologia Industrial/métodos , Fósforo-Oxigênio Liases/genética , Bacillus thuringiensis/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cromatografia Líquida de Alta Pressão , Fosfatos de Dinucleosídeos/química , Fosfatos de Dinucleosídeos/isolamento & purificação , Liofilização , Fósforo-Oxigênio Liases/química , Fósforo-Oxigênio Liases/metabolismo
15.
Mol Cell Proteomics ; 12(5): 1363-76, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23408684

RESUMO

Bacillus thuringiensis is a well-known entomopathogenic bacterium used worldwide as an environmentally compatible biopesticide. During sporulation, B. thuringiensis accumulates a large number of parasporal crystals consisting of insecticidal crystal proteins (ICPs) that can account for nearly 20-30% of the cell's dry weight. However, the metabolic regulation mechanisms of ICP synthesis remain to be elucidated. In this study, the combined efforts in transcriptomics and proteomics mainly uncovered the following 6 metabolic regulation mechanisms: (1) proteases and the amino acid metabolism (particularly, the branched-chain amino acids) became more active during sporulation; (2) stored poly-ß-hydroxybutyrate and acetoin, together with some low-quality substances provided considerable carbon and energy sources for sporulation and parasporal crystal formation; (3) the pentose phosphate shunt demonstrated an interesting regulation mechanism involving gluconate when CT-43 cells were grown in GYS medium; (4) the tricarboxylic acid cycle was significantly modified during sporulation; (5) an obvious increase in the quantitative levels of enzymes and cytochromes involved in energy production via the electron transport system was observed; (6) most F0F1-ATPase subunits were remarkably up-regulated during sporulation. This study, for the first time, systematically reveals the metabolic regulation mechanisms involved in the supply of amino acids, carbon substances, and energy for B. thuringiensis spore and parasporal crystal formation at both the transcriptional and translational levels.


Assuntos
Bacillus thuringiensis/fisiologia , Proteínas de Bactérias/genética , Transcriptoma , Acetoína/metabolismo , Proteínas de Bactérias/metabolismo , Ciclo do Ácido Cítrico , Hidroxibutiratos/metabolismo , Anotação de Sequência Molecular , Fosforilação Oxidativa , Via de Pentose Fosfato , Poliésteres/metabolismo , Biossíntese de Proteínas , Proteoma/genética , Proteoma/metabolismo , Proteômica , ATPases Translocadoras de Prótons/genética , ATPases Translocadoras de Prótons/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Esporos Bacterianos/fisiologia , Transcrição Gênica
16.
Sci Total Environ ; 437: 196-9, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22940044

RESUMO

Four typical freshwater fish species in Lake Taihu (TH), China, were collected and analyzed for the residue levels of DDT and its metabolites DDD and DDE (sum of o,p'- and p,p'-DDT, DDD, and DDE is designated as DDTs). The DDTs concentrations ranged from 3.24 to 37.1 ng/g, and p,p'-DDE was the dominant isomer, followed by p,p'-DDD and o,p'-DDT. Source identification indicated that DDTs in TH was mostly stemmed from the historical usage of technical DDT mixture, but a new source of DDT, i.e., dicofol-type DDT, also occurred. The results from the present work, together with previously published data, clearly indicate that dicofol-type DDT was widespread and was an important continual source of DDTs in China.


Assuntos
DDT/análise , Peixes , Poluentes Químicos da Água/análise , Animais , China , DDT/metabolismo , Dicofol/análise , Monitoramento Ambiental , Inseticidas/análise , Lagos/análise
17.
Vet Immunol Immunopathol ; 144(3-4): 255-8, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22041600

RESUMO

The reactivity of different lectins with crude chromogranin A (CgA) obtained from different animals, namely, cow, horse, dog, pig, and dolphin, was examined to identify lectin(s) that would be useful as coating reagent(s) in a sandwich enzyme-linked immunosorbent assay (ELISA). Of the different lectins studied, the Amaranthus caudatus lectin (ACA), which is specific for the Thomsen-Friedenreich (T)-antigen (Galß1-3GalNAc), was found to react with the CgA from different animals by western blotting. Purified rabbit anti-bovine CgA antibody was also found to cross-react with the crude CgA preparations. On the basis of these findings, a sandwich ELISA was developed with ACA as the coating reagent and anti-bovine CgA antibody as the probing antibody. Using this method, concentration-dependent curves ranging from 0.003 µg/mL to 25 µg/mL and from 0.02 µg/mL to 25 µg/mL were obtained for bovine CgA and canine CgA, respectively. Similarly, concentration-dependent curves were obtained for the equine, swine, and dolphin crude CgA extracts. Thus, ACA is concluded to be a valuable reagent for CgA detection in crude extracts from different animal species, and for CgA isolation/purification.


Assuntos
Glândulas Suprarrenais/química , Amaranthus/imunologia , Antígenos Glicosídicos Associados a Tumores/imunologia , Cromogranina A/análise , Ensaio de Imunoadsorção Enzimática/métodos , Lectinas de Plantas/imunologia , Animais , Western Blotting , Bovinos , Cromogranina A/imunologia , Cães , Golfinhos , Eletroforese em Gel de Poliacrilamida , Cavalos , Coelhos/imunologia , Suínos , Extratos de Tecidos/química
18.
J Chromatogr A ; 1218(25): 3830-6, 2011 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-21601213

RESUMO

A novel, simple and efficient dispersive liquid-liquid microextraction based on solidification of floating organic droplet (DLLME-SFO) technique coupled with high-performance liquid chromatography with ultraviolet detection (HPLC-UV) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed for the determination of triclosan and its degradation product 2,4-dichlorophenol in real water samples. The extraction solvent used in this work is of low density, low volatility, low toxicity and proper melting point around room temperature. The extractant droplets can be collected easily by solidifying it at a lower temperature. Parameters that affect the extraction efficiency, including type and volume of extraction solvent and dispersive solvent, salt effect, pH and extraction time, were investigated and optimized in a 5 mL sample system by HPLC-UV. Under the optimum conditions (extraction solvent: 12 µL of 1-dodecanol; dispersive solvent: 300 of µL acetonitrile; sample pH: 6.0; extraction time: 1 min), the limits of detection (LODs) of the pretreatment method combined with LC-MS/MS were in the range of 0.002-0.02 µg L(-1) which are lower than or comparable with other reported approaches applied to the determination of the same compounds. Wide linearities, good precisions and satisfactory relative recoveries were also obtained. The proposed technique was successfully applied to determine triclosan and 2,4-dichlorophenol in real water samples.


Assuntos
Fracionamento Químico/métodos , Clorofenóis/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Triclosan/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Clorofenóis/análise , Modelos Lineares , Reprodutibilidade dos Testes , Rios , Sensibilidade e Especificidade , Triclosan/análise , Poluentes Químicos da Água/análise
20.
Bioconjug Chem ; 21(7): 1341-8, 2010 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-20583783

RESUMO

Although the tetracysteine (TC) motif has been used as a tag, the binding stability between TC motif and biarsenical reagent against extreme conditions as well as its capacity as a quantitative tag remains not well developed. To reveal these problems, we chose enoyl-acyl carrier protein reductase (FabI), which was involved in the final step of elongation in the bacterial fatty acid biosynthesis, to be tagged by the TC motif. Taking enhanced green fluorescent protein (EGFP) tagged FabI as a control, we investigated the activities of various TC tagged FabIs (N-terminus, C-terminus, or both N- and C-terminus TC motif). The results showed that all the TC tagged FabIs had high enzyme activities while the EGFP tagged FabI exhaustively lost the activity. Beside this, the characteristics of the tag, including labeling stability against extreme conditions, capacity for quantitative analysis, and ability for in-cell labeling, were also investigated. We demonstrated for the first time that the binding between FlAsH reagent and TC motif was stable against high pressure, high field strength, high temperature, and ultrasound. Furthermore, we verified the potential of TC motif for quantitative analysis of target protein by different approaches, including SDS-PAGE, spectrofluorometry (SPF), and capillary zone electrophoresis (CZE).


Assuntos
Arsenicais/química , Enoil-(Proteína de Transporte de Acila) Redutase (NADH)/química , Proteínas de Escherichia coli/química , Escherichia coli/enzimologia , Tetraciclina/química , Enoil-(Proteína de Transporte de Acila) Redutase (NADH)/metabolismo , Proteínas de Escherichia coli/metabolismo , Ácido Graxo Sintase Tipo II , Cinética
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