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1.
Brief Bioinform ; 22(5)2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-33847357

RESUMO

Bridging heterogeneous mutation data fills in the gap between various data categories and propels discovery of disease-related genes. It is known that genome-wide association study (GWAS) infers significant mutation associations that link genotype and phenotype. However, due to the differences of size and quality between GWAS studies, not all de facto vital variations are able to pass the multiple testing. In the meantime, mutation events widely reported in literature unveil typical functional biological process, including mutation types like gain of function and loss of function. To bring together the heterogeneous mutation data, we propose a 'Gene-Disease Association prediction by Mutation Data Bridging (GDAMDB)' pipeline with a statistic generative model. The model learns the distribution parameters of mutation associations and mutation types and recovers false-negative GWAS mutations that fail to pass significant test but represent supportive evidences of functional biological process in literature. Eventually, we applied GDAMDB in Alzheimer's disease (AD) and predicted 79 AD-associated genes. Besides, 12 of them from the original GWAS, 60 of them are supported to be AD-related by other GWAS or literature report, and rest of them are newly predicted genes. Our model is capable of enhancing the GWAS-based gene association discovery by well combining text mining results. The positive result indicates that bridging the heterogeneous mutation data is contributory for the novel disease-related gene discovery.


Assuntos
Doença de Alzheimer/genética , Estudos de Associação Genética/métodos , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Mutação , Polimorfismo de Nucleotídeo Único , Algoritmos , Biologia Computacional/métodos , Mineração de Dados/métodos , Redes Reguladoras de Genes/genética , Genótipo , Humanos , Fenótipo , Mapas de Interação de Proteínas/genética , Reprodutibilidade dos Testes
2.
J Chem Phys ; 151(15): 154502, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31640381

RESUMO

The transport behavior of ionic liquids (ILs) is pivotal for a variety of applications, especially when ILs are used as electrolytes. Many aspects of the transport dynamics of ILs remain to be understood. Here, a common ionic liquid, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BmimNTf2), was studied with molecular dynamics simulations. The results show that BmimNTf2 displays typical structural relaxation, subdiffusive behavior, and a breakdown of the Stokes-Einstein diffusion relation as in glass-forming liquids. In addition, the simulations show that the translational dynamics, reorientation dynamics, and structural relaxation dynamics are well described by the Vogel-Fulcher-Tammann equation like fragile glass forming liquids. Building on previous work that employed ion cage models, it was found that the diffusion dynamics of the cations and anions were well described by a hopping process random walk where the step time is the ion cage lifetime obtained from the cage correlation function. Detailed analysis of the ion cage structures indicated that the electrostatic potential energy of the ion cage dominates the diffusion dynamics of the caged ion. The ion orientational relaxation dynamics showed that ion reorientation is a necessary step for ion cage restructuring. The dynamic ion cage model description of ion diffusion presented here may have implications for designing ILs to control their transport behavior.

3.
Parasitol Res ; 118(1): 97-109, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30353232

RESUMO

Trypanosoma lewisi (Kinetoplastea: Trypanosomatida: Trypanosomatidae) with a cosmopolitan distribution is the type species of the subgenus Herpetosoma, which includes ca. 50 nominal species isolated mainly from rodents. Since members of Herpetosoma in different host species have an almost identical morphology of bloodstream forms, these trypanosomes are referred to as 'T. lewisi-like', and the molecular genetic characterization of each species is necessary to verify their taxonomy. In the present study, we collected blood samples from 89 murid rodents of 15 species and 11 soricids of four species in Indonesia, Philippines, Vietnam, Taiwan, and mainland China for the detection of hemoprotozoan infection. T. lewisi and T. lewisi-like trypanosomes were found in the blood smears of 10 murid animals, which included Bandicota indica (two rats), Rattus argentiventer (one rat), and Rattus tiomanicus (two rats) in Indonesia; Rattus rattus (one rat) in the Philippines; and Niviventer confucianus (four rats) in mainland China. Furthermore, large- or medium-sized non-T. lewisi-like trypanosomes were detected in two soricids, Crocidura dracula in Vietnam and Anourosorex yamashinai in Taiwan, respectively. Molecular genetic characterization of the small subunit (SSU) ribosomal RNA gene (rDNA) and glycosomal glyceraldehyde-3-phosphate dehydrogenase (gGAPDH) gene indicated that the trypanosomes from all the murid hosts had identical SSU rDNA or gGAPDH gene nucleotide sequences except for those in N. confucianus in mainland China. These N. confucianus-infecting trypanosomes also showed several unique morphological features such as smaller bodies, anteriorly positioned nuclei, and larger rod-shaped kinetoplasts when compared with T. lewisi trypomastigotes. Trypanosoma (Herpetosoma) niviventerae n. sp. is erected for this new species. Similarly, based on morphological and molecular genetic characterization, Trypanosoma sapaensis n. sp. and Trypanosoma anourosoricis n. sp. are proposed for the trypanosomes in C. dracula in Vietnam and A. yamashinai in Taiwan, respectively. More effort directed toward the morphological and molecular genetic characterization of the trypanosomes of rodents and soricids is required to fully understand the real biodiversity of their hemoflagellates.


Assuntos
Murinae/parasitologia , Ratos/parasitologia , Doenças dos Roedores/parasitologia , Trypanosoma/classificação , Tripanossomíase/veterinária , Animais , Sudeste Asiático/epidemiologia , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Ásia Oriental/epidemiologia , Gliceraldeído-3-Fosfato Desidrogenases/genética , Filogenia , Proteínas de Protozoários/genética , Doenças dos Roedores/sangue , Doenças dos Roedores/epidemiologia , Análise de Sequência de DNA/veterinária , Trypanosoma/citologia , Trypanosoma/genética , Trypanosoma/isolamento & purificação , Trypanosoma lewisi/genética , Trypanosoma lewisi/isolamento & purificação , Tripanossomíase/epidemiologia , Tripanossomíase/parasitologia
4.
Adv Exp Med Biol ; 1093: 263-279, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30306487

RESUMO

The lumbar spinal stenosis (LSS) is a kind of orthopedic disease which causes a series of neurological symptom. Vertebral lamina grinding operation is a key procedure in decompressive laminectomy for LSS treatment. With the help of image-guided navigation system, the robot-assisted technology is applied to reduce the burdens on surgeon and improve the accuracy of the operation. This paper proposes a multilevel fuzzy control based on force information in the robot-assisted decompressive laminectomy to improve the quality and the robotic dynamic performance in surgical operation. The controlled grinding path is planned in the medical images after 3D reconstruction, and the mapping between robot and images is realized by navigation registration. Multilevel fuzzy controller is used to adjust the feed rate to keep the grinding force stable. As the vertebral lamina contains different components according to the anatomy, it has different mechanical properties as the main reason causing the fluctuation of force. A feature extraction method for texture recognition of bone is introduced to improve the accuracy of component classification. When the inner cortical bone is reached, the feeding operation needs to stop to avoid penetration into spinal cord and damage to the spinal nerves. Experiments are conducted to evaluate the dynamic stabilities of the control system and state recognition.


Assuntos
Processamento de Imagem Assistida por Computador , Laminectomia , Procedimentos Cirúrgicos Robóticos , Coluna Vertebral/cirurgia , Cirurgia Assistida por Computador , Lógica Fuzzy , Humanos , Fenômenos Mecânicos
5.
Chemistry ; 23(64): 16338-16345, 2017 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-28850752

RESUMO

A series of Ca-doped lithium vanadates Li3-x Cax VO4 (x=0, 0.01, 0.03, and 0.05) are synthesized successfully through a simple sol-gel method. XRD patterns and energy-dispersive X-ray spectroscopy (EDS) mappings reveal that the doped Ca2+ ions enter into the lattice successfully and are distributed uniformly throughout the Li3 VO4 (LVO) grains. XRD spectra and SEM images show that Ca doping can lead to an enlarged lattice and refined Li3 VO4 particles. A small quantity of V ions will transfer from V5+ to V4+ in the Ca-doped samples, as demonstrated by the X-ray photoelectron spectroscopy (XPS) analysis, which leads to an increase of an order of magnitude in the electronic conductivity. Improved rate capability and cycling stability are observed for the Ca-doped samples, and Li2.97 Ca0.03 VO4 exhibits the best electrochemical performance among the studied materials. The initial charge/discharge capacities at 0.1 C increase from 480/645 to 527/702 mA h g-1 as x varies from 0 to 0.03. The charge capacity of Li2.97 Ca0.03 VO4 at 1 C retains 95.3 % of its initial value after 180 cycles, whereas the capacity retention is only 40 % for the pristine sample. Moreover, Li2.97 Ca0.03 VO4 maintains a high discharge capacity of 301.7 mA h g-1 at a high discharge rate (4 C), whereas the corresponding value is only 95.2 mA h g-1 for the pristine LVO sample. The enhanced cycling and rate performances are ascribed to the increased lithium ion diffusivity and electrical conductivity induced by Ca doping.

6.
Front Microbiol ; 15: 1389046, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38832118

RESUMO

Introduction: Microplastics (MPs), identified as emerging contaminants, have been detected across diverse environmental media. Their enduring presence and small size facilitate the adsorption of organic pollutants and heavy metals, leading to combined pollution effects. MPs also accumulate in the food chain thus pose risks to animals, plants, and human health, garnering significant scholarly attention in recent years. Aerobic granular sludge (AGS) technology emerges as an innovative approach to wastewater treatment. However, the impacts of MPs on the operational efficiency and microbial characteristics of AGS systems has been insufficiently explored. Methods: This study investigated the effects of varying concentration (10, 50, and 100 mg/L) of biodegradable MPs (Polylactic Acid, PLA) and non-biodegradable MPs (Polyethylene Terephthalate, PET) on the properties of AGS and explored the underlying mechanisms. Results and discussions: It was discovered that low and medium concentration of MPs (10 and 50 mg/L) showed no significant effects on COD removal by AGS, but high concentration (100 mg/L) of MPs markedly diminished the ability to remove COD of AGS, by blocking most of the nutrient transport channels of AGS. However, both PLA and PE promoted the nitrogen and phosphorus removal ability of AGS, and significantly increased the removal efficiency of total inorganic nitrogen (TIN) and total phosphorus (TP) at stages II and III (P < 0.05). High concentration of MPs inhibited the growth of sludge. PET noticeably deteriorate the sedimentation performance of AGS, while 50 mg/L PLA proved to be beneficial to sludge sedimentation at stage II. The addition of MPs promoted the abundance of Candidatus_Competibacter and Acinetobacter in AGS, thereby promoting the phosphorus removal capacity of AGS. Both 50 mg/L PET and 100 mg/L PLA caused large amount of white Thiothrix filamentous bacteria forming on the surface of AGS, leading to deterioration of the sludge settling performance and affecting the normal operation of the reactor. Comparing with PET, AGS proved to be more resistant to PLA, so more attention should be paid to the effect of non-biodegradable MPs on AGS in the future.

7.
Hum Mutat ; 34(8): 1094-101, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23592378

RESUMO

Neural tube defects (NTDs) are severe birth malformations that affect one in 1,000 live births. Recently, mutations in the planar cell polarity (PCP) pathway genes had been implicated in the pathogenesis of NTDs in both the mouse model and in human cohorts. Mouse models indicate that the homozygous disruption of Sec24b, which mediates the ER-to-Golgi transportation of the core PCP gene Vangl2 as a component of the COPII vesicle, will result in craniorachischisis. In this study, we found four rare missense heterozygous SEC24B mutations (p.Phe227Ser, p.Phe682Leu, p.Arg1248Gln, and p.Ala1251Gly) in NTDs cases that were absent in all controls. Among them, p.Phe227Ser and p.Phe682Leu affected its protein stability and physical interaction with VANGL2. Three variants (p.Phe227Ser, p.Arg1248Gln, and p.Ala1251Gly) were demonstrated to affect VANGL2 subcellular localization in cultured cells. Further functional analysis in the zebrafish including overexpression and dosage-dependent rescue study suggested that these four mutations all displayed loss-of-function effects compared with wild-type SEC24B. Our study demonstrated that functional mutations in SEC24B might contribute to the etiology of a subset of human NTDs and further expanded our knowledge of the role of PCP pathway-related genes in the pathogenesis of human NTDs.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular/química , Proteínas de Membrana/química , Mutação de Sentido Incorreto , Defeitos do Tubo Neural/genética , Proteínas de Transporte Vesicular/química , Proteínas de Transporte Vesicular/genética , Animais , Estudos de Casos e Controles , Polaridade Celular , Feminino , Expressão Gênica , Variação Genética , Células HEK293 , Células HeLa , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Defeitos do Tubo Neural/etiologia , Defeitos do Tubo Neural/patologia , Estabilidade Proteica , Estrutura Quaternária de Proteína , Análise de Sequência de DNA , Proteínas de Transporte Vesicular/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/genética
8.
Wei Sheng Wu Xue Bao ; 52(5): 602-10, 2012 May 04.
Artigo em Zh | MEDLINE | ID: mdl-22803346

RESUMO

OBJECTIVE: Gamma-butyrobetaine hydroxylase is an enzyme that catalyzes the last step in the biosynthesis of L-carnitine. We cloned, expressed and characterized a gamma-butyrobetaine hydroxylase gene bbh from Pseudomonas sp. L-1, to facilitate the production of L-carnitine using microorganisms. METHODS: We cloned bbh gene by PCR, and then cloned the open reading frame of bbh into pET-15b vector and expressed by Isopropyl beta-D-1-thiogalactopyranoside (IPTG) induction. After His-Bind Resin purification, the characteristics of BBH were studied. The three-dimensional structure of BBH monomer was modeled by SWISS-MODEL Workspace and resting cells were used for L-carnitine transformation. RESULTS: We cloned a gamma-butyrobetaine hydroxylase gene bbh (GenBank: JQ250036) from Pseudomonas sp. L-1 and expressed the gene in Escherichia coli BL21(DE3). BBH fusion protein was a homodimer, and the molecular weight of subunit was about 46.5kDa. The optimal temperature and pH was 30 degrees C and pH 7.5. The enzyme was stable below 45 degrees C. The enzyme was most stable at pH 6.0. We used resting cells of recombinant E. coli for L-carnitine biotransformation, after incubated at 30 degrees C and pH 7.0 for 31 h, the concentration of L-carnitine reached 12.7 mmol/L. CONCLUSION: The bbh gene from Pseudomonas sp. L-1 strain is remarkably different from that of reported one. The gamma-butyrobetaine hydroxylase expressed by this gene could effectively transform gamma-butyrobetaine for L-carnitine production. Beside by reporting of a bbh gene from bacteria, this research also provided a new process for biotransformation of L-carnitine.


Assuntos
Pseudomonas/enzimologia , gama-Butirobetaína Dioxigenase/química , gama-Butirobetaína Dioxigenase/genética , Clonagem Molecular , Estabilidade Enzimática , Escherichia coli/enzimologia , Escherichia coli/genética , Escherichia coli/metabolismo , Concentração de Íons de Hidrogênio , Modelos Moleculares , Pseudomonas/genética , Pseudomonas/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Temperatura , gama-Butirobetaína Dioxigenase/biossíntese , gama-Butirobetaína Dioxigenase/isolamento & purificação
10.
Nanomaterials (Basel) ; 11(12)2021 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-34947715

RESUMO

In this study, we studied the synergetic effect of potassium oxysalts on combustion and ignition of nano aluminum (Al) and nano copper oxide (CuO) composites. Potassium periodate (KIO4) and potassium perchlorate (KClO4) are good oxidizers with high oxygen content and strong oxidizability. Different contents of KIO4 and KClO4 were added to nano Al/CuO and the composites were assembled by sonication. When the peak pressure of nano Al/CuO was increased ~5-13 times, the pressurization rate was improved by ~1-3 orders of magnitude, the ignition delay time was shortened by ~0.08 ms-0.52 ms and the reaction completeness was adjustable when 30-70% KIO4 and KClO4 were added into the composites. The reaction of Al/KIO4 and Al/KClO4 at a lower temperature was helpful to ignite the ternary composite. Meanwhile, CuO significantly reduced the peak temperature of oxygen released from the decomposition of KIO4 and KClO4. The synergetic effect of binary oxidizers made the combustion performance of the ternary composites better than that of the binary composites. The present work indicates that KIO4 and KClO4 are promising additives for nano Al/CuO to tune and promote the combustion performance. The ternary composites have potential application in energy devices and combustion apparatus.

11.
Protein Expr Purif ; 69(1): 16-20, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19800407

RESUMO

Purification of a cis-epoxysuccinic acid hydrolase was achieved by ammonium sulfate precipitation, ionic exchange chromatography, hydrophobic interaction chromatography followed by size-exclusion chromatography. The enzyme was purified 177-fold with a yield of 14.4%. The apparent molecular mass of the enzyme was determined to be 33kDa under denaturing conditions. The optimum pH for enzyme activity was 7.0, and the enzyme exhibited maximum activity at about 45 degrees C in 50mM sodium phosphate buffer (pH 7.5). EDTA and o-phenanthrolin inhibited the enzyme activity remarkably, suggesting that the enzyme needs some metal cation to maintain its activity. Results of inductively coupled plasma mass spectrometry analysis indicated that the cis-epoxysuccinic acid hydrolase needs Zn(2+) as a cofactor. Eight amino acids sequenced from the N-terminal region of the cis-epoxysuccinic acid hydrolase showed the same sequence as the N-terminal region of the beta subunit of the cis-epoxysuccinic acid hydrolase obtained from Alcaligenes sp.


Assuntos
Bordetella/enzimologia , Hidrolases/isolamento & purificação , Hidrolases/metabolismo , Ácido Succínico/metabolismo , Sequência de Aminoácidos , Eletroforese em Gel de Poliacrilamida , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Hidrolases/antagonistas & inibidores , Hidrolases/química , Cinética , Dados de Sequência Molecular , Ácido Succínico/química , Temperatura
12.
Lipids ; 44(2): 161-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18989717

RESUMO

Diacylglycerol (DAG) supplementation has been shown to be associated with the reduction of postprandial triacylglycerol (TAG) concentration, although the extent of the association is uncertain. We quantitatively examined the effect of dietary DAG on postprandial serum TAG concentration by conducting a meta-analysis of randomized controlled trials. Potential papers were initially searched for in the electronic databases of Medline, Embase and Cochrane library. Inclusion criteria required the trial to be randomized with DAG as the treatment group, and TAG as the control group. Information was extracted independently by two investigators and the effect of DAG on postprandial TAG concentration was examined in Review Manager 4.2. Seven papers were included in the statistic pooling. DAG supplementation reduced the increment of postprandial TAG concentration significantly at postprandial 2 h (Weighted mean difference (WMD) -0.07 mmol/L; 95% CI -0.13 to 0.00 mmol/L; P = 0.05), 4 h (WMD -0.15 mmol/L; 95% CI -0.24 to -0.06 mmol/L; P = 0.002) and 6 h (WMD -0.14 mmol/L; 95% CI -0.23 to -0.05 mmol/L; P = 0.002). Linear regression showed that the effect of DAG was positively correlated with the daily dosage at 2 h (P = 0.095) and 6 h (P = 0.053) after lipid loading. In conclusion, compared with TAG oil, DAG reduced the postprandial serum TAG concentration at 2 h, 4 h and 6 h postprandial and was positively correlated with daily dosage.


Assuntos
Diglicerídeos/farmacologia , Período Pós-Prandial , Triglicerídeos/sangue , Adulto , Diglicerídeos/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
13.
RSC Adv ; 9(41): 23888-23893, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35530635

RESUMO

The compatible catalytic structure of NiCo2O4 was modified into multi-shelled hollow spheres by one-pot synthesis, followed by heat treatment. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Brunauer-Emmet-Teller (BET) and N2 adsorption-desorption approaches were used for the characterizations of nanoparticles and multi-shelled hollow porous structures and the morphologies and crystal structures of these hollow spheres, respectively. Differential scanning calorimetry (DSC) was adopted for comparing the thermal decomposition performances of ammonium perchlorate (AP) catalyzed by adding different contents of multi-shelled NiCo2O4 hollow spheres. Impressively, the experimental results showed that the NiCo2O4 hollow spheres exhibited more excellent catalytic activity than NiCo2O4 nanoparticles as a result of their large specific surface areas, good adsorption capacity and many active reduction sites. The decomposition temperature of AP with multi-shelled NiCo2O4 hollow spheres could be reduced up to 322.3 °C from 416.3 °C. Furthermore, a catalytic mechanism was proposed for the thermal decomposition of AP over multi-shelled NiCo2O4 hollow spheres based on electron transfer processes.

14.
Bioresour Technol ; 99(13): 5391-6, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18083551

RESUMO

Response surface methodology, which allows for rapid identification of important factors and optimization of them to enhance enzyme production, was employed here to optimize culture conditions for the production of cis-epoxysuccinic acid hydrolase from Bordetella sp. strain 1-3. In the first step, a Plackett-Burman design was used to evaluate the effects of nine variables (yeast extract, cis-epoxysuccinic acid, KH(2)PO(4), K(2)HPO(4).3H(2)O, MgSO(4).7H(2)O, trace minerals solution, culture volume, initial pH and incubation time) on the enzyme production. Yeast extract, cis-epoxysuccinic acid and KH(2)PO(4) had significant influences on cis-epoxysuccinic acid hydrolase production and their concentrations were further optimized using central composite design and response surface analysis. A combination of adjusting the concentration of yeast extract to 7.8 g/l, cis-epoxysuccinic acid to 9.8 g/l, and KH(2)PO(4) to 1.12 g/l would favor maximum cis-epoxysuccinic acid hydrolase production. An enhancement of cis-epoxysuccinic acid hydrolase production from 5.6 U/ml to 9.27 U/ml was gained after optimization.


Assuntos
Bordetella/enzimologia , Epóxido Hidrolases/metabolismo , Compostos de Epóxi/metabolismo , Ácido Succínico/metabolismo , Animais , Proteínas de Bactérias/metabolismo , Fermentação , Cinética , Mamíferos , Propriedades de Superfície , Tartaratos/metabolismo
15.
FEMS Microbiol Lett ; 267(2): 214-20, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17166227

RESUMO

A bacterial strain 1-3 capable of enantioselectively hydrolyzing cis-epoxysuccinic acid to D(-)-tartaric acid was isolated from soil. Phenotypic characteristics, Biolog GN test and phylogenetic analysis of strain 1-3 indicated that it belongs to the genus Bordetella. cis-Epoxysuccinic acid could be used as a carbon source and inducer for production of cis-epoxysuccinic acid hydrolase. After the purification of the enzymatic biotransformed product, a colorless and scentless crystal was obtained, which was confirmed to be the tartaric acid with laevorotatory optical rotation by the (1)H nuclear magnetic resonance spectrum and optical rotation analysis.


Assuntos
Bordetella/metabolismo , Succinatos/metabolismo , Tartaratos/metabolismo , Proteínas de Bactérias/metabolismo , Biotransformação , Bordetella/classificação , Bordetella/isolamento & purificação , Carbono/metabolismo , Hidrolases/metabolismo , Succinatos/química , Tartaratos/química
16.
Sci Total Environ ; 579: 871-880, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27884524

RESUMO

We assembled mesocosms to address the coherent mechanisms that an increasing phosphorus (P) concentration in water columns coupled with the phytoplankton bloom and identify the performance gap of regulating phytoplankton growth between two macrophyte species, Ceratophyllum demersum L. and Vallisneria spiralis L. Intense alkaline phosphatase activities (APA) were observed in the unplanted control, with their predominant part, phytoplankton APA (accounting for up to 44.7% of the total APA), and another large share, bacterial APA. These correspond with the large average concentration of total phosphorus (TP), total dissolved phosphorus (TDP) and soluble reactive (SRP) as well as high phytoplankton density in the water column. The consistency among P concentrations, phytoplankton density and APA, together with the positive impact of phytoplankton density on total APA revealed by the structural equation modelling (SEM), indicates that facilitated APA levels in water is an essential strategy for phytoplankton to enhance the available P. Furthermore, a positive interaction between phytoplankton APA and bacteria APA was detected, suggesting a potential collaboration between phytoplankton and bacteria to boost available P content in the water column. Both macrophyte species had a prominent performance on regulating phytoplankton proliferation. The phytoplankton density and quantum yield in C. demersum systems were all significantly lower (33.8% and 24.0%) than those in V. spiralis systems. Additionally, a greater decoupling effect of C. demersum on the relationship between P, APA, phytoplankton density, bacteria dynamic and quantum yield was revealed by SEM. These results imply that the preferred tactic of different species could lead to the performance gap.


Assuntos
Monitoramento Ambiental , Fósforo/análise , Fitoplâncton/fisiologia , Poluentes Químicos da Água/análise , Bactérias , Biomassa , Lagos , Nitrogênio , Plantas , Água
17.
Sheng Wu Gong Cheng Xue Bao ; 28(7): 813-22, 2012 Jul.
Artigo em Zh | MEDLINE | ID: mdl-23167193

RESUMO

In order to characterize a thermostable urate oxidase (Uox) from Microbacterium sp. strain ZZJ4-1, we cloned its gene (uox). The open reading frame of uox contained 894 base pairs and encoded a protein with 297 amino acids. Alignment of gene sequences indicated there was no obvious identity with the most reported uox and that 72% identity was found with uox from Arthrobacter globiformis. We inserted the gene into the plasmid pET-15b to construct an expression vector pET-15b-uox and got it induced expression in Escherichia coli BL21 (DE3). After the purification of the recombinant Uox by the HisBind column, we studied some properties of it. It was composed of subunits with a molecular mass of about 35 kDa. The optimal temperature and pH was 30 degrees C and pH 7.5. It was stable below 65 degrees C and from pH 8.5 to 11.0. The Km value was 0.22 mmol/L with the uric acid as the substrate. Ag+, Zn2+, CU2+ and SDS could totally inhibit its activity while Tween 20, Tween 80 and Triton X-100 had a slight promotion effect. The thermal stability of this enzyme was the most excellent among the reported recombinant Uox. Based on this property, it would be very useful in the application.


Assuntos
Actinomycetales/enzimologia , Urato Oxidase/genética , Actinomycetales/genética , Sequência de Aminoácidos , Clonagem Molecular , Estabilidade Enzimática , Escherichia coli/genética , Escherichia coli/metabolismo , Vetores Genéticos/genética , Dados de Sequência Molecular , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Urato Oxidase/metabolismo
18.
Neuropharmacology ; 61(3): 524-43, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21530552

RESUMO

The median (MR) and dorsal raphe (DR) nuclei contain the majority of the 5-hydroxytryptamine (5-HT, serotonin) neurons that project to limbic forebrain regions, are important in regulating homeostatic functions and are implicated in the etiology and treatment of mood disorders and schizophrenia. The primary synaptic inputs within and to the raphe are glutamatergic and GABAergic. The DR is divided into three subfields, i.e., ventromedial (vmDR), lateral wings (lwDR) and dorsomedial (dmDR). Our previous work shows that cell characteristics of 5-HT neurons and the magnitude of the 5-HT(1A) and 5-HT(1B) receptor-mediated responses in the vmDR and MR are not the same. We extend these observations to examine the electrophysiological properties across all four raphe subfields in both 5-HT and non-5-HT neurons. The neurochemical topography of glutamatergic and GABAergic cell bodies and nerve terminals were identified using immunohistochemistry and the morphology of the 5-HT neurons was measured. Although 5-HT neurons possessed similar physiological properties, important differences existed between subfields. Non-5-HT neurons were indistinguishable from 5-HT neurons. GABA neurons were distributed throughout the raphe, usually in areas devoid of 5-HT neurons. Although GABAergic synaptic innervation was dense throughout the raphe (immunohistochemical analysis of the GABA transporters GAT1 and GAT3), their distributions differed. Glutamate neurons, as defined by vGlut3 anti-bodies, were intermixed and co-localized with 5-HT neurons within all raphe subfields. Finally, the dendritic arbor of the 5-HT neurons was distinct between subfields. Previous studies regard 5-HT neurons as a homogenous population. Our data support a model of the raphe as an area composed of functionally distinct subpopulations of 5-HT and non-5-HT neurons, in part delineated by subfield. Understanding the interaction of the cell properties of the neurons in concert with their morphology, local distribution of GABA and glutamate neurons and their synaptic input, reveals a more complicated and heterogeneous raphe. These results provide an important foundation for understanding how specific subfields modulate behavior and for defining which aspects of the circuitry are altered during the etiology of psychological disorders.


Assuntos
Química Encefálica , Neurônios/fisiologia , Neurônios/ultraestrutura , Núcleos da Rafe/fisiologia , Núcleos da Rafe/ultraestrutura , Receptor 5-HT1A de Serotonina/metabolismo , Receptor 5-HT1B de Serotonina/metabolismo , Transmissão Sináptica , Animais , Dendritos/fisiologia , Dendritos/ultraestrutura , Impedância Elétrica , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Transportador de Glucose Tipo 3/metabolismo , Glutamato Descarboxilase/metabolismo , Imuno-Histoquímica , Masculino , Potenciais da Membrana , Técnicas de Patch-Clamp , Núcleos da Rafe/química , Ratos , Ratos Sprague-Dawley , Triptofano Hidroxilase/metabolismo
19.
Sheng Wu Gong Cheng Xue Bao ; 26(3): 335-40, 2010 Mar.
Artigo em Zh | MEDLINE | ID: mdl-20518346

RESUMO

We purified a sarcosine oxidase from Bacillus sp. strain BSD-8 isolated from soil. We purified the enzyme by ammonium sulfate precipitation, DEAE-cellulose, Toyopearl hydrophobic and Sephadex G-75 molecular sieve chromatography and characterized the purified sarcosine oxidase. This sarcosine oxidase was a flavin enzyme containing a noncovalently bound flavin with the subunit molecular mass of 51 kDa. The optimal temperature for this enzyme was 60 degrees C and it showed its highest activity at pH 8.5. It was stable in the pH range of 8.0-10.0 and at the temperature of 60 degrees C. Estimated by Lineveaver-Burk plots, the K(m) of the enzyme was 3.1 mmol/L. Ag+, Hg2+, SDS and Tween 80 dramatically inhibted the enzyme activity, whereas Tween 20 and Triton X-100 had no effect on enzyme activity. The thermostability of this enzyme was better than reported sarcosine oxidases, and it could be applied in enzymatic measuring of creatinine.


Assuntos
Bacillus/enzimologia , Sarcosina Oxidase/isolamento & purificação , Sarcosina Oxidase/metabolismo , Bacillus/isolamento & purificação , Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Precipitação Química , Estabilidade Enzimática , Sarcosina Oxidase/química , Microbiologia do Solo
20.
Asia Pac J Clin Nutr ; 17(3): 415-21, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18818161

RESUMO

The effects of diacylglycerol (DAG) on body weight are not consistent in clinical trials. This meta-analysis of randomized controlled trials was conducted to evaluate the efficacy of dietary DAG on body weight. Potential articles were initially searched from the electronic databases of Medline, Embase and Cochrane library using the subject keywords as follows: weight, DAG, triacylglycerol (TAG), reduction and obesity. Inclusion criteria required the trial to be randomized placebo controlled with body weight as an endpoint. Two reviewers independently extracted the information and evaluated the methodological quality using the scoring system developed by Jadad. Meta-analysis was performed with the software of Review Manager 4.2. The robustness of overall analysis was tested by sensitivity analysis and publication bias was visually inspected by funnel plot. Five published trials were included in the statistical pool. The meta-analysis indicated a significant difference in body weight reduction between group receiving DAG and group receiving TAG (weighted mean difference -0.75 kg; 95% CI: -1.11 to -0.39; p < 0.0001). Sensitivity analysis corroborated the result of the overall analysis. Linear regression analysis showed that there was significant correlation between daily dose and body weight reduction (p = 0.044, R2 = 0.889). In conclusion, this meta-analysis suggested that DAG was efficacious for reducing body weight compared with TAG and this effect was influenced by the daily dose.


Assuntos
Peso Corporal/efeitos dos fármacos , Diglicerídeos/farmacologia , Obesidade/tratamento farmacológico , Redução de Peso , Adulto , Relação Dose-Resposta a Droga , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Triglicerídeos/farmacologia , Redução de Peso/efeitos dos fármacos , Redução de Peso/fisiologia , Adulto Jovem
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