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1.
Front Microbiol ; 13: 828990, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464970

RESUMO

Genomic information for bacteria within the genus Rahnella remains limited. Rahnella sp. JZ-GX1 was previously isolated from the Pinus massoniana rhizosphere in China and shows potential as a plant growth-promoting (PGP) bacterium. In the present work, we combined the GridION Nanopore ONT and Illumina sequencing platforms to obtain the complete genome sequence of strain JZ-GX1, and the application effects of the strain in natural field environment was assessed. The whole genome of Rahnella sp. JZ-GX1 comprised a single circular chromosome (5,472,828 bp, G + C content of 53.53%) with 4,483 protein-coding sequences, 22 rRNAs, and 77 tRNAs. Based on whole genome phylogenetic and average nucleotide identity (ANI) analysis, the JZ-GX1 strain was reidentified as R. victoriana. Genes related to indole-3-acetic acid (IAA), phosphorus solubilization, nitrogen fixation, siderophores, acetoin, 1-aminocyclopropane-1-carboxylate (ACC) deaminase, gamma-aminobutyric acid (GABA) production, spermidine and volatile organic compounds (VOCs) biosynthesis were present in the genome of strain JZ-GX1. In addition, these functions were also confirmed by in vitro experiments. Importantly, compared to uninoculated control plants, Pyrus serotina, Malus spectabilis, Populus euramericana (Dode) Guinier cv. "San Martino" (I-72 poplar) and Pinus elliottii plants inoculated with strain JZ-GX1 showed increased heights and ground diameters. These findings improve our understanding of R. victoriana JZ-GX1 as a potential biofertilizer in agriculture.

2.
Plant J ; 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35352402

RESUMO

The meadowfoam family (Limnanthaceae) is one of the smallest and genomically underexplored families of the Brassicales. The Limnanthaceae harbor about seven species in the genus Limnanthes (meadowfoam) and Floerkea proserpinacoides (false mermaidweed), all native to North America. Because all Limnanthes and Floerkea species have only five chromosome pairs, i.e., a chromosome number rare in Brassicales and shared with Arabidopsis thaliana (Arabidopsis), we examined the Limnanthaceae genomes as a potential model system. Using low-coverage whole-genome sequencing data, we reexamined phylogenetic relationships and characterized the repeatomes of Limnanthaceae genomes. Phylogenies based on complete chloroplast and 35S rDNA sequences corroborated the sister relationship between Floerkea and Limnanthes and two major clades in the latter genus. The genome size of Limnanthaceae species ranges from 1.5 to 2.1 Gb, apparently due to the large increase in DNA repeats, which constitute 60-70% of their genomes. Repeatomes are dominated by long terminal repeat retrotransposons, while tandem repeats represent only less than 0.5% of the genomes. The average chromosome size in Limnanthaceae species (340-420 Mb) is more than 10 times larger than in Arabidopsis (32 Mb). A three-dimensional fluorescence in situ hybridization analysis demonstrated that the five chromosome pairs in interphase nuclei of Limnanthes species adopt the Rabl-like configuration.

3.
Sheng Li Xue Bao ; 73(4): 559-570, 2021 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-34405212

RESUMO

Prostaglandins are a class of poly-unsaturated fatty acids-derived bioactive lipids with important physiological function by binding to specific receptors. Prostaglandin receptors lack specific antibodies, which greatly impedes the research on our understanding of the signaling of prostaglandins. The aim of this study was to identify nine mouse lines with amino terminal (-NH2, -N) HA-tagged prostaglandin receptors by using the combination of artificial sperm and CRISPR-Cas9 technology. The guide RNA expression plasmid and labeled targeting vector plasmids were transferred into "artificial sperm cells". The "artificial sperm cells" containing labeled proteins were selected and injected into mouse oocytes, and implanted into pseudopregnant mice to obtain labeled mice. The genomic DNA of the prostaglandin receptor tagged mice was extracted, and the genotypes of mice were detected by PCR method. We also isolated mouse peritoneal macrophages to verify the protein expression of HA-labeled prostaglandin receptor by Western blot. Specific DNA bands were amplified in prostaglandin receptor labeled mice, and specific HA protein bands were detected in macrophage proteins, which was not detected in wild type mice. In summary, we successfully constructed 9 mouse lines with HA-tagged prostaglandin receptors, providing a powerful tool for further study of the pathophysiological functions of prostaglandin signaling both in vivo and in vitro.


Assuntos
RNA Guia , Receptores de Prostaglandina , Animais , Camundongos , Oócitos , Plasmídeos
4.
J Agric Food Chem ; 69(25): 7000-7015, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34139119

RESUMO

High intake of dietary fibers was found to be inversely associated with type-2 diabetes (T2D), whereas the difference among different dietary fibers on T2D remains unclear. Therefore, we have investigated the effects of different dietary fibers on T2D. Nine types of dietary fibers were used to investigate and evaluate their effects on type-2 diabetic rats via physiology, genomics, and metabolomics. We found that supplementation with ß-glucan, arabinogalactan, guar gum, apple pectin, glucomannan, and arabinoxylan significantly reduced the fasting blood glucose, whereas carrageenan, xylan, and xanthan gum did not affect glycemic control in diabetic rats. Also, bioactive dietary fibers (ß-glucan, arabinogalactan, guar gum, and apple pectin) associated with the increased butyric acid level and abundance of beneficial bacteria (Lachnobacterium, Parabacteroides, Faecalibacterium, Akkermansia, and some butyric acid-producing bacteria), as well as improved host metabolism by decreasing 12α-hydroxylated bile acids, acylcarnitines, and amino acids (leucine, phenylalanine, citrulline, etc.), thereby exert beneficial effects on T2D. It was also found that ß-glucan might attenuate insulin resistance via downregulation of Prevotella copri-mediated biosynthesis of branched-chain amino acids in T2D. Together, our study uncovered the effects of different dietary fibers on T2D, along with their potential mechanism.


Assuntos
Diabetes Mellitus Experimental , Microbioma Gastrointestinal , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Fibras na Dieta , Hipoglicemiantes , Prevotella , Ratos
5.
Crit Rev Food Sci Nutr ; : 1-23, 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33591236

RESUMO

Food nutrients plays a crucial role in human health, especially in gastrointestinal (GI) health. The effect of food nutrients on human health mainly depends on the digestion and fermentation process in the GI tract. In vitro GI digestion and fermentation models had the advantages of reproducibility, simplicity, universality, and could integrally simulate the in vivo conditions to mimic oral, gastric, small intestinal and large intestinal digestive processes. They could not only predict the relationship among material composition, structure and digestive characteristics, but also evaluate the bioavailability of material components and the impact of digestive metabolites on GI health. This review systematicly summarized the current state of the in vitro simulation models, and made detailed descriptions for their applications, advantages and disadvantages, and specially their applications in food carbohydrates. In addition, it also provided the suggestions for the improvement of in vitro models and firstly proposed to establish a set of standardized methods of in vitro dynamic digestion and fermentation conditions for food carbohydrates, which were in order to further evaluate more effects of the nutrients on human health in future.

6.
Int J Biol Macromol ; 154: 25-30, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32171833

RESUMO

The antidiabetic function of polysaccharides prepared from six legumes: soybean, white kidney bean, red kidney bean, small black soybean, field bean, lentil were studied. Six legume polysaccharides' antidiabetic function in high-fat diet and streptozotocin-induced type II diabetic mice were compared. Their effects on body weight, fasting blood glucose (FBG), glycosylated serum protein (GSP), serum insulin levels (HOMA-IR), blood lipids (including total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-c), and high-density lipoprotein cholesterol (HDL-c)) were tested. Results showed that red kidney bean polysaccharides (RK) could alleviate the symptoms of emaciation, decreased the levels of FBG, GSP, TC, LDL-c and obviously reduced the concentration of TG and HOMA-IR (p < 0.05). RK exhibited greater antidiabetic potential in type II diabetic mice, compared with other legume polysaccharides. The chemical composition of six legume polysaccharides were determined. Composition analysis indicated that the six legume polysaccharides were obviously different in moisture, ash, neutral sugar, uronic acid, total phenolic content, total flavonoid content, amino acid composition and monosaccharide composition. Results indicated that the antidiabetic activities of RK might due to its higher content and specific structure of polysaccharide.


Assuntos
Fabaceae/química , Hipoglicemiantes/farmacologia , Polissacarídeos/farmacologia , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/tratamento farmacológico , Jejum/sangue , Hipoglicemiantes/uso terapêutico , Insulina/sangue , Lipídeos/sangue , Masculino , Camundongos , Polissacarídeos/uso terapêutico
7.
Food Funct ; 11(4): 2886-2897, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32186298

RESUMO

This work investigated the physiochemical characteristics and preventive effects of purified pectin (H121, L13 and L102) with different esterification degrees on dextran sulfate sodium (DSS)-induced colitis in mice. Three doses of each type of pectin were administered to C57BL/6J mice for 7 days before the DSS treatment, with dextran and mesalazine as positive controls. Results showed that pathological factors including the body weight, the disease activity index (DAI), the colonic weight/length ratio and the organ index of the spleen were improved with pre-intervention of a high dose of L13 or L102. Further studies showed that administration of a low dose of L13, low dose and medium dose of L102 or dextran improved intestinal permeability and tight junction function in colitis mice. Treatments of L13 of all doses and L102 of a high dose downregulated the oxidative stress-associated factors, while L102 of a low dose and H121 ameliorated the inflammatory cytokine production in serum and the colon. The above results suggested that pectin could attenuate DSS-induced intestinal epithelial injury, inflammation and oxidative stress. Specifically, compared to high esterified pectin, low esterified pectin displayed better protective effects in acute colitis mice.


Assuntos
Colite Ulcerativa/prevenção & controle , Alimento Funcional , Pectinas/administração & dosagem , Administração Oral , Animais , Colite Ulcerativa/induzido quimicamente , Dextranos , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Distribuição Aleatória , Organismos Livres de Patógenos Específicos
8.
Can Respir J ; 2019: 2697376, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31379980

RESUMO

Aim: The transmembrane chemokine (C-X-C motif) ligand 16 (CXCL16) plays a vital role in the pathogenesis of organ fibrosis, including the liver and kidney. However, the detailed biological function of CXCL16 is still not fully understood in the progression of pulmonary fibrosis (PF). The aim of present study is to examine the function of CXCL16 in PF. Materials and Methods: In this study, we constructed the PF model on mouse by using bleomycin and analyzed the effect of the mouse recombinant protein CXCL16 on mouse lung fibroblast L929 (LF) as well. To further examine the connection between CXCL16 and STAT3 in mouse LF cells, the STAT3 inhibitor AG490 was utilized to inhibit the expression of STAT3. Meanwhile, lipopolysaccharide was used to enhance the phosphorylation of STAT3 (p-STAT3) in mouse LF cells. Results: Our results indicated that the level of CXCL16/CXCR6 was significantly upregulated in the mouse PF model. Moreover, the level of p-STAT3 was also promoted. In addition, the mouse recombinant protein CXCL16 not only contributed to the proliferation of mouse LF cells but also induced the expression of p-STAT3 in LF cells. However, the effect of CXCL16 was deeply abolished by the STAT3 inhibitor AG490 in LF cells. Meanwhile, the antibody of CXCL16 deeply reduced the phosphorylation of STAT3 in lipopolysaccharide (LPS) cultured cells. Conclusions: All these results demonstrated that CXCL16 promoted the phosphorylation of STAT3 and further demonstrated that STAT3 was a critical component in CXCL16/CXCR6 signaling pathway. This research not only enhanced the comprehension of CXCL16 but also indicated its potential value as a target in the treatment for human PF.


Assuntos
Quimiocina CXCL16/sangue , Modelos Animais de Doenças , Fibrose Pulmonar/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Estudos de Casos e Controles , Linhagem Celular , Progressão da Doença , Lipopolissacarídeos , Masculino , Camundongos , Fosforilação , Fator de Transcrição STAT3/antagonistas & inibidores , Tirfostinas
9.
Biomaterials ; 195: 75-85, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30616030

RESUMO

Targeted drug delivery with precisely controlled drug release and activation is highly demanding and challenging for tumor precision therapy. Herein, a biomimetic cascade nanoreactor (designated as Mem@GOx@ZIF-8@BDOX) is constructed for tumor targeted starvation therapy-amplified chemotherapy by assembling tumor cell membrane cloak and glucose oxidase (GOx) onto zeolitic imidazolate framework (ZIF-8) with the loading prodrug of hydrogen peroxide (H2O2)-sensitive BDOX. Biomimetic membrane camouflage affords superior immune evasion and homotypic binding capacities, which significantly enhance the tumor preferential accumulation and uptake for targeted drug delivery. Moreover, GOx-induced glycolysis would cut off glucose supply and metabolism pathways for tumor starvation therapy with the transformation of tumor microenvironments. Importantly, this artificial adjustment could trigger the site-specific BDOX release and activation for cascade amplified tumor chemotherapy regardless of the complexity and variability of tumor physiological environments. Both in vitro and in vivo investigations indicate that the biomimetic cascade nanoreactor could remarkably improve the therapeutic efficacy with minimized side effects through the synergistic starvation therapy and chemotherapy. This biomimetic cascade strategy would contribute to developing intelligent drug delivery systems for tumor precision therapy.


Assuntos
Biomimética/métodos , Nanopartículas/química , Animais , Glucose Oxidase/química , Humanos , Peróxido de Hidrogênio/química , Estruturas Metalorgânicas , Pró-Fármacos/química , Zeolitas/química
10.
Plant J ; 93(6): 1088-1101, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29381236

RESUMO

Brachypodium distachyon is a well-established model monocot plant, and its small and compact genome has been used as an accurate reference for the much larger and often polyploid genomes of cereals such as Avena sativa (oats), Hordeum vulgare (barley) and Triticum aestivum (wheat). Centromeres are indispensable functional units of chromosomes and they play a core role in genome polyploidization events during evolution. As the Brachypodium genus contains about 20 species that differ significantly in terms of their basic chromosome numbers, genome size, ploidy levels and life strategies, studying their centromeres may provide important insight into the structure and evolution of the genome in this interesting and important genus. In this study, we isolated the centromeric DNA of the B. distachyon reference line Bd21 and characterized its composition via the chromatin immunoprecipitation of the nucleosomes that contain the centromere-specific histone CENH3. We revealed that the centromeres of Bd21 have the features of typical multicellular eukaryotic centromeres. Strikingly, these centromeres contain relatively few centromeric satellite DNAs; in particular, the centromere of chromosome 5 (Bd5) consists of only ~40 kb. Moreover, the centromeric retrotransposons in B. distachyon (CRBds) are evolutionarily young. These transposable elements are located both within and adjacent to the CENH3 binding domains, and have similar compositions. Moreover, based on the presence of CRBds in the centromeres, the species in this study can be grouped into two distinct lineages. This may provide new evidence regarding the phylogenetic relationships within the Brachypodium genus.


Assuntos
Brachypodium/genética , Centrômero/genética , DNA de Plantas/genética , Genoma de Planta/genética , Sequência de Aminoácidos , Brachypodium/classificação , Brachypodium/metabolismo , Centrômero/metabolismo , Cromossomos de Plantas/genética , Cromossomos de Plantas/metabolismo , DNA de Plantas/metabolismo , Evolução Molecular , Histonas/genética , Histonas/metabolismo , Hibridização in Situ Fluorescente , Nucleossomos/genética , Nucleossomos/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Poliploidia , Ligação Proteica , Homologia de Sequência de Aminoácidos
11.
Sci Rep ; 7: 41659, 2017 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-28134354

RESUMO

Sugarcane (Saccharum hybrids spp.) is the most important sugar crop that accounts for ~75% of the world's sugar production. Recently, a whole-genome sequencing project was launched on the wild species S. spontaneum. To obtain information on the DNA composition of the repeat-enriched region of the centromere, we conducted a genome-wide analysis of the DNA sequences associated with CenH3 (a mutant of histone H3 located in eukaryote centromeres) using chromatin immunoprecipitation followed by sequencing (ChIP-seq) method. We demonstrate that the centromeres contain mainly SCEN-like single satellite repeat (Ss1) and several Ty3/gypsy retrotransposon-related repeats (Ss166, Ss51, and Ss68). Ss1 dominates in the centromeric regions and spans up to 500 kb. In contrast, the Ty3/gypsy retrotransposon-related repeats are either clustered spanning over a short range, or dispersed in the centromere regions. Interestingly, Ss1 exhibits a chromosome-specific enrichment in the wild species S. spontaneum and S. robustum, but not in the domesticated species S. officinarum and modern sugarcane cultivars. This finding suggests an autopolyploid genome identity of S. spontaneum with a high level of homology among its eight sub-genomes. We also conducted a genome-wide survey of the repetitive DNAs in S. spontaneum following a similarity-based sequence clustering strategy. These results provide insight into the composition of sugarcane genome as well as the genome assembly of S. spontaneum.


Assuntos
Centrômero/genética , Genoma de Planta , Sequências Repetitivas de Ácido Nucleico , Saccharum/genética , Elementos de DNA Transponíveis , Histonas/genética , Ploidias
12.
BMC Pulm Med ; 16(1): 124, 2016 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-27544078

RESUMO

BACKGROUND: Autonomic dysfunction in patients with chronic obstructive pulmonary disease (COPD) may increase the risks of arrhythmia and sudden death. We studied cardiac autonomic function in patients with acute exacerbation of COPD (AECOPD). METHODS: Patients with AECOPD were classified into ventricular tachycardia (VT) and non-VT groups according to the presence or absence of VT. The following parameters derived from 24-h Holter monitoring were compared between groups: average heart rate, heart rate deceleration capacity (DC), heart rate acceleration capacity (AC), standard deviation of normal RR intervals (SDNN), standard deviation of average RR interval in 5-min segments (SDANN), root mean square of standard deviations of differences between adjacent normal RR intervals (rMSSD), low-frequency power (LF), high-frequency power (HF) and LF/HF ratio. RESULTS: Seventy patients were included, 22 in the VT group and 48 in the non-VT group. The groups had similar clinical characteristics (except for more common amiodarone use in the VT group, P < 0.05) and general ECG characteristics. DC, SDNN, SDANN and rMSSD were lower and AC higher in the VT group (P < 0.05). In the VT group, DC was correlated positively with SDNN (r = 0.716), SDANN (r = 0.595), rMSSD (r = 0.571) and HF (r = 0.486), and negatively with LF (r = -0.518) and LF/HF (r = -0.458) (P < 0.05). AC was correlated negatively with SDNN (r = -0.682), SDANN (r = -0.567) and rMSSD (r = -0.548) (P < 0.05). CONCLUSIONS: DC decreased and AC increased in patients with AECOPD and VT, reflecting an imbalance in autonomic regulation of the heart that might increase the risk of sudden death.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Coração/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/complicações , Taquicardia Ventricular/fisiopatologia , Doença Aguda , Idoso , China , Progressão da Doença , Eletrocardiografia Ambulatorial , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taquicardia Ventricular/complicações
13.
Nanoscale ; 7(26): 11393-400, 2015 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-26073879

RESUMO

The critical doping structures of rare-earth atoms in the promising ß-SiAlON phosphors have long been argued owing to the lack of direct evidence. Here, the exact locations and coordination of the Ce rare-earth atoms in the ß-SiAlON structure have been examined using an atom-resolved Cs-corrected scanning transmission electron microscope. Three different occupation sites for the Ce atoms have been directly observed: two of them are in the structural channel coordinated with six and nine N(O) atoms, respectively; the other one is the unexpected substitution site for Si(Al). The chemical valences and stabilities of the doping Ce ions at the different occupation sites have been evaluated using density functional calculations. Correlation of the different doping structures with the luminescence properties has been investigated by the aid of cathodoluminescence (CL) microanalysis, which verifies the different contribution of the interstitial trivalent Ce ions to the light emission while no luminescence is observed for the substitutional doping of quadrivalent Ce.

14.
J Photochem Photobiol B ; 127: 94-9, 2013 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-23973779

RESUMO

Despite the fact that the luminescence reaction mechanism of aequorin has been intensively investigated, details in luminescence such as the effect of important amino acids residues and explicit water molecules on spectroscopic properties of coelenteramide remain unclear. In this work, the effect of amino acids residues His16, Tyr82, Trp86, Phe113, Trp129, Tyr132, explicit water molecules Wat505 and Wat405 on the spectral properties of CLM(-) has been studied by CAM-B3LYP, TD M06L and TD CAM-B3LYP methods in hydrophobic environment and aqueous solution. In hydrophobic environment, the amino acids or water molecules have no significant effect on the absorption. Tyr82 and Trp86 move close to CLM(-) changes the hydrogen bond network, and thus, the spectral properties is significantly affected by the hydrogen bonds between His16H(+)+Tyr82+Trp86 and CLM(-). Tyr82, Trp86 hydrogen bonding to CLM(-) upshifts the excited energy and helps emission spectra shift to blue region. Therefore, it is concluded that His16H(+)+Tyr82+Trp86 modify the emission spectra. The molecular electrostatic potential indicated that the greater electron density is located at the oxygen atom of 6-p-hydroxyphenyl group of CLM(-), and it facilitates the formation of hydrogen bond with His16H(+)+Tyr82+Trp86. It is a critical condition for the modification of emission spectra. It is expected to help to understand the interactions between emitter and amino acids in the micro environment.


Assuntos
Equorina/química , Aminoácidos , Benzenoacetamidas/química , Medições Luminescentes , Pirazinas/química , Água , Absorção , Domínio Catalítico , Ligação de Hidrogênio , Modelos Moleculares
15.
Photochem Photobiol ; 89(4): 849-55, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23495829

RESUMO

The dynamics simulation and quantum chemical calculation are employed to investigate spectrum properties of deprotonation process of coelenteramide and two final states neutral state and phenolate anion. According to the calculation results, theoretical evidence supporting the luminescence mechanism hypothesis is proposed in a significant bioluminescence process. In vivo of marine bioluminescent organisms, if the protein motion provides the conditions for the deprotonation of coelenteramide in some protein molecules, the phenolate anion is completely deprotonated coelenteramide as an emitter in these protein molecules and emits fluorescence assigned to the lower energy peak. And in another emitter in which the condition of deprotonation is not met, the fluorescence is produced by the neutral state of coelenteramide and assigned to the higher energy peak. The energy difference decreases gradually when the proton of coelenteramide gradually approaches to His22. For phenolate anion and neutral state, electronic cloud distributions between their each frontier molecular orbitals HOMO and LUMO have high overlapping volume. The molecular electrostatic potential indicates that for phenolate anion, the oxygen atom after deprotonation has greater electron density, which is good for formation hydrogen bonds with amino acids in the environment.


Assuntos
Benzenoacetamidas/química , Luminescência , Pirazinas/química , Simulação por Computador , Modelos Químicos , Modelos Moleculares , Espectroscopia Fotoeletrônica , Conformação Proteica , Espectrofotometria Atômica , Estereoisomerismo
16.
Dongwuxue Yanjiu ; 33(1): 60-6, 2012 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-22345010

RESUMO

The tree shrews, as an ideal animal model receiving extensive attentions to human disease research, demands essential research tools, in particular cellular markers and monoclonal antibodies for immunological studies. In this paper, a 1 365 bp of the full-length CD4 cDNA encoding sequence was cloned from total RNA in peripheral blood of tree shrews, the sequence completes two unknown fragment gaps of tree shrews predicted CD4 cDNA in the GenBank database, and its molecular characteristics were analyzed compared with other mammals by using biology software such as Clustal W2.0 and so forth. The results showed that the extracellular and intracellular domains of tree shrews CD4 amino acid sequence are conserved. The tree shrews CD4 amino acid sequence showed a close genetic relationship with Homo sapiens and Macaca mulatta. Most regions of the tree shrews CD4 molecule surface showed positive charges as humans. However, compared with CD4 extracellular domain D1 of human, CD4 D1 surface of tree shrews showed more negative charges, and more two N-glycosylation sites, which may affect antibody binding. This study provides a theoretical basis for the preparation and functional studies of CD4 monoclonal antibody.


Assuntos
Antígenos CD4/genética , Clonagem Molecular , Tupaia/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Antígenos CD4/química , Humanos , Mamíferos/classificação , Mamíferos/genética , Modelos Moleculares , Dados de Sequência Molecular , Fases de Leitura Aberta , Filogenia , Estrutura Terciária de Proteína , Alinhamento de Sequência , Tupaia/classificação
17.
Zhonghua Jie He He Hu Xi Za Zhi ; 34(3): 182-6, 2011 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-21569684

RESUMO

OBJECTIVE: To investigate the urodynamic changes in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS) and nocturnal polyuria. METHODS: From Sept. 2002 to Jun. 2008, 23 patients with nocturnal polyuria were diagnosed as having OSAHS by polysomnography (PSG). The number and output of nocturia, the osmotic pressure and the excretion of Na(+) were recorded during both the PSG night and CPAP titrating night. Plasma levels of brain natriuretic peptide (BNP) and atrial natriuretic peptides (ANP) were also measured at 11PM in the 2 nights and 7AM in the next mornings. Urodynamic studies including urine flow, bladder pressure during filling, pressure-flow study during voiding and urethral pressure were carried out in these patients. Urodynamic studies were performed again after treatment with CPAP for 3 months. RESULTS: PSG showed that the patients with nocturnal polyuria had moderate to severe OSAHS, in which the apnea-hypopnea index (AHI) being 48 ± 15 events per hour. The number of nocturnal voiding during the PSG night was more than that during the CPAP titrating night. During the PSG night, the output of nocturia, the nocturia excretion of Na(+), ANP levels (at 7am in the next morning after PSG night) increased and the osmotic pressure of nocturia decreased. CPAP therapy could reverse these abnormalities. The main characteristics of urodynamics in these patients included weak detrusor contraction, hypoesthesia in filling cystometry, and decreased bladder compliance, and detrusor external sphincter dyssynergia. After 3 months of CPAP treatment, both the motility of the detrusor of bladder and the bladder compliance improved. CONCLUSIONS: CPAP therapy can effectively reverse the nocturnal polyuria in OSAHS patients. In OSAHS patients, the features of nocturia, including the changes of output, osmotic pressure and the excretion of Na(+), may be related to the secretion of high-level of ANP. During the course of chronic progressively OSAHS pathophysiology, detrusor function of bladder may be damaged. CPAP therapy could decrease the nocturnal excretion of ANP, and improve the motility of the detrusor of bladder.


Assuntos
Poliúria/fisiopatologia , Apneia Obstrutiva do Sono/fisiopatologia , Apneia Obstrutiva do Sono/urina , Adulto , Idoso , Idoso de 80 Anos ou mais , Fator Natriurético Atrial/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Noctúria/fisiopatologia , Noctúria/urina , Poliúria/urina , Bexiga Urinária/fisiopatologia , Urodinâmica
18.
Dongwuxue Yanjiu ; 31(5): 483-9, 2010 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-20979250

RESUMO

The use of tree shrews (Tupaia belangeri) in human disease studies demands essential research tools, in particular cellular markers and their monoclonal antibodies for immunological studies. Here we cloned the full-length cDNAs encoding CD3E from total RNA of the spleen, liver and peripheral blood of tree shrews and analyzed their structural characteristics in comparison with other mammals by Discovery Studio software. The results showed that the open reading frame sequence of tree shrew CD3E was 582 bp, encoding 194 amino acids. The overall structure of tree shrew CD3E protein was similar to its counterparts of other mammals, intracellular and transmembrane domain highly conserved. However, detailed analysis revealed two potential glycosylation sites and different surface charges in the extracellular domain. Availability of the entire open-reading-frame and related sequence information would therefore facilitate the preparation of monoclonal antibodies against tree shrew CD3 and further studies for its function.


Assuntos
Complexo CD3/genética , Tupaiidae/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Complexo CD3/química , Clonagem Molecular , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Filogenia
20.
J Chem Theory Comput ; 5(8): 2021-9, 2009 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-26613144

RESUMO

The mechanism of the reaction of imidogen (NH) with fulminic acid (HCNO) has been investigated theoretically using the multiconfigurational self-consistent-field theory (MCSCF), multireference Rayleigh-Schrodinger perturbation theory (RSPT2), and coupled cluster theory (CC) along with the complete basis set extrapolations (CBS). The calculations show that the NH + HCNO reaction takes place via an N → C addition mechanism predominantly by surmounting a small barrier (ca. ∼3 kcal/mol). The adduct is HC(NH)NO in the triplet state with an exothermicity of more than 60 kcal/mol. The subsequent C-N cleavage, which is nearly barrierless, leads to HCNH and NO as the final products. This represents the most energetically favorable product channel of the title reaction. The channels leading to HCN, HNC, HNO, or HON via O- or H-migration mechanisms involve higher barriers and thus are negligible. The singlet-triplet crossing has been investigated as well for the HCNH + NO product channel by locating the conical interactions. Using transition state theory, the rate constants were predicted as a function of temperatures. It is suggested that the NH + HCNO reaction might be an alternative source for the NO regeneration under the combustion conditions. This calculation is useful to simulate experimental investigations of the NH + HCNO reaction.

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