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1.
Genet Mol Res ; 15(4)2016 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-27819734

RESUMO

Although the palynology and sporophyte stage of Isöetes sinensis have been well studied, the biology of its gametophyte and embryo is less well understood. To date, the functions of several genes of I. sinensis and the molecular mechanisms of enzymes encoded by them remain to be studied. In the present study, the Fe-SOD gene of I. sinensis was successfully cloned using RT-PCR and rapid amplification of cDNA ends (RACE), and termed IsFeSOD. IsFeSOD has certain reference value in the classification of system evolution. The study also accumulated data for further research on the SOD gene. Bioinformatic analysis was employed to compare IsFeSOD with gene sequences obtained from other plants present in the GenBank. Furthermore, the recombinant pET32-FeSOD plasmids were transformed into Escherichia coli BL21 for expression. IsFeSOD was observed to have 1469 nucleotides that were predicted to encode 247 amino acids. The bioinformatic analysis revealed that IsFeSOD contained conserved TGGGA sequences, similar to eight other species, in addition to five other conserved sequences. The recombinant protein was about 43 kDa. Recombinant FeSOD was expressed, purified, and confirmed by western blotting. Alignment of complete Fe-SOD mRNA sequences from 9 species revealed several conserved sequences. A phylogenetic tree was constructed using MEGA4.1 and ClustalX multiple-sequence alignment programs. This study could be helpful in further characterization of SOD genes and for classification of system evolution status.


Assuntos
Briófitas/enzimologia , Briófitas/genética , Regulação da Expressão Gênica de Plantas , Superóxido Dismutase/genética , Sequência de Aminoácidos , Sequência de Bases , Western Blotting , Clonagem Molecular , DNA Complementar/genética , Regulação Enzimológica da Expressão Gênica , Filogenia , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Superóxido Dismutase/química , Superóxido Dismutase/metabolismo
2.
Zhonghua Wai Ke Za Zhi ; 54(8): 632-6, 2016 Aug 01.
Artigo em Chinês | MEDLINE | ID: mdl-27502142

RESUMO

OBJECTIVE: To evaluate the anesthetic efficacy of periprostatic nerve block in transrectal ultrasound(TRUS) guided biopsy on different prostate volume. METHODS: A total of 568 patients received prostate biopsy in Department of Urology, Subei People's Hospital from May 2013 to September 2015 were retrospectively studied. All patients were divided into local anesthesia group and nerve block group according to different way of anesthesia. Then each group was divided into four subgroups(20-40 ml, >40-60 ml, >60-100 ml and >100 ml subgroups) according to different prostate volume range. After being anaesthetized successfully, patients in two groups underwent prostate biopsy, visual analogue scale(VAS) scores, visual numeric scale(VNS)scores and complications were recorded and analyzed. At inter-group and intra-group in local anesthesia group and nerve block group, Mann-Whitney U test of non-parametric analysis and single factor variance analysis were used to compare the VAS scores and the VNS scores respectively, and chi-square test was used to compare the rates of complication. RESULTS: The VAS scores of four subgroups: local anesthesia group: 1.9±0.9, 2.8±1.5, 3.8±2.3 and 5.3±2.5; nerve block group: 1.5±0.7, 2.0±0.8, 2.9±1.7 and 4.2±2.0. The VNS scores: local anesthesia group: 3.4±0.6, 2.9±0.6, 2.7±0.5 and 1.6±0.7; nerve block group: 3.7±0.5, 3.3±0.4, 3.0±0.8 and 2.0±0.7. The VAS scores and the VNS scores had significant differences (Z=-3.637-98.253, all P<0.05) at inter-group or intra-group level. For the complication rates of operation, hematuria, blood, urinary retention were significant differences (F=1.347-15.402, all P<0.05) at intra-group level. But there were no significant differences at inter-group level(P>0.05). CONCLUSION: Compared with local anesthesia, ultrasound guided prostate peripheral nerve block anesthesia has great analgesic effect and high safety, but for patients with a large prostate volumethe analgesic effect is inefficiency.


Assuntos
Anestesia Local/métodos , Anestésicos Locais/administração & dosagem , Biópsia Guiada por Imagem , Lidocaína/administração & dosagem , Bloqueio Nervoso/métodos , Próstata/diagnóstico por imagem , Próstata/patologia , Análise de Variância , Biópsia por Agulha , Distribuição de Qui-Quadrado , Humanos , Masculino , Medição da Dor , Estudos Retrospectivos , Ultrassonografia de Intervenção , Escala Visual Analógica
3.
Nanoscale ; 6(21): 12414-20, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25238442

RESUMO

The luminescence of semiconductor nanostructures is strongly dependent on their size, dimensions, morphology, composition, or defects, and their band emissions can be properly and selectively tailored through the rational manipulation of these parameters during material growth. Using spatially-resolved cathodoluminescence spectroscopy, monochromatic contrast maps and high-resolution transmission electron microscopy, an obvious red-shift of the near-band-edge emission of wurtzite ZnS nanobelts, resulting from a strip of stacking faults or a zinc-blende phase with tens of atomic layers in width, has been observed and its related mechanism has been discussed. This finding is not specific to the defect-dependent optical properties tailoring of ZnS nanostructures and represents a general validity for clarifying the mechanism of peak-shift (band-gap expansion or shrinking) of a wide range of semiconductor nanostructures with various defects. In addition, the general formation mechanism of the belt-like nanostructure was proposed based on precise microstructure analyses on a ZnS nanobelt with atomic terrace growth fronts.

4.
IET Nanobiotechnol ; 5(4): 126-31, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22149868

RESUMO

Neopterin is a catabolic product of guanosine triphosphate, a purine nucleotide. Measuring neopterin concentrations in biological fluids such as urine provides information about cellular immune activation in humans under control of T helper cells. A high neopterin concentration in bodily fluids, including serum and urine, indicates cellular immunity activation, which is associated with oxidative stress. In this work, neopterin is the target molecule and imprinted onto poly(ethylene-co-vinyl alcohol) via solvent evaporation. The template molecules on the thin film are then removed, and the membrane is used as a sensing element for electrochemical urinalysis. Poly(ethylene-co-vinyl alcohol) containing 27 mol% ethylene had high imprinting effectiveness and may be integrated with the proposed portable biosensor. In random urine analysis, the cyclic voltammetry measurements of neopterin with an additional recovery method achieved >95% recovery for the neopterin concentration of 15 ng/mL.


Assuntos
Técnicas Biossensoriais/instrumentação , Impressão Molecular/métodos , Neopterina/química , Polivinil/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas , Eletrodos , Humanos , Neopterina/urina , Propriedades de Superfície
5.
J Phys Chem B ; 109(46): 21521-4, 2005 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-16853794

RESUMO

GaN nanowires with P doping were synthesized via a simple thermal evaporation process. The P-doped GaN nanowires have average diameters of approximately 100 nm and lengths up to tens of micrometers. Scanning electron microscope and high-resolution field-emission transmission electron microscope analyses revealed that P doping results in a rough surface morphology of GaN nanowires. Field-emission measurements showed that P doping effectively decreases the turn-on field of GaN nanowire to 5.1 V/mum, holding promise of application as an electron emitter. The rough surface is responsible for enhancement of the field-emission properties of GaN nanowires.

6.
J Biol Chem ; 276(25): 22332-40, 2001 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-11297539

RESUMO

Indole-3-carbinol (I3C), a compound naturally occurring in Brassica vegetables, can induce a G(1) cell cycle arrest of human MCF-7 breast cancer cells that is accompanied by the selective inhibition of cyclin-dependent kinase 6 (CDK6) expression. Reverse transcriptase-polymerase chain reaction analysis of CDK6 mRNA decay rates revealed that I3C had no effect on CDK6 transcript stability. We report the first identification and functional characterization of the CDK6 promoter in order to determine whether I3C inhibits CDK6 transcription. In MCF-7 cells stably transfected with CDK6 promoter-linked luciferase reporter plasmids, I3C inhibited CDK6 promoter activity in an I3C-specific response that was not a consequence of the growth-arrested state of the cells. Deletion analysis revealed a 167-base pair I3C-responsive region of the CDK6 promoter between -805 and -638. Site-specific mutations within this region revealed that both Sp1 and Ets-like sites, which are spaced 5 base pairs apart, were necessary for I3C responsiveness in the context of the CDK6 promoter. Electrophoretic mobility shift analysis of protein-DNA complexes formed with nuclear proteins isolated from I3C-treated and -untreated cells, in combination with supershift assays using Sp1 antibodies, demonstrated that the Sp1-binding site in the CDK6 promoter forms a specific I3C-responsive DNA-protein complex that contains the Sp1 transcription factor. Taken together, our results suggest that I3C down-regulates CDK6 transcription by targeting Sp1 at a composite DNA site in the CDK6 promoter.


Assuntos
Neoplasias da Mama/patologia , Ciclo Celular/efeitos dos fármacos , Quinases Ciclina-Dependentes , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Indóis/farmacologia , Regiões Promotoras Genéticas , Proteínas Serina-Treonina Quinases/genética , Fator de Transcrição Sp1/metabolismo , Sequência de Bases , Neoplasias da Mama/genética , Clonagem Molecular , Quinase 6 Dependente de Ciclina , Primers do DNA , Humanos , Mutagênese , Proteínas Nucleares/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
7.
Artigo em Chinês | MEDLINE | ID: mdl-12571938

RESUMO

OBJECTIVE: Twenty-six species of human parasites were recorded in Zhejiang Province in 1987-1989 as a part of the national investigation on the distribution of human parasites, and the total prevalence was 80.2%. In order to find out possible changes on the composition of parasite species and decrease of prevalence after control intervention particularly mass chemotherapy in the past years and provide evidence for an improved control strategy, the second sampled survey was carried out from 1998 to 1999. METHODS: Ten counties were identified randomly out of 28 counties where the last survey was conducted following the same sampling method. Same technics were used for case detection and data processing. RESULTS: The total infection rate in a sample of 15,698 was 22.84% was 22.84% in 30 investigation spots in 10 counties, and 17 species of parasites were revealed. The overall prevalence was reduced by 71.51% in comparison to that of 1989, and the number of parasite species was 17, 9 less than that of the last investigation. CONCLUSIONS: The prevalence of human parasites has greatly declined in this province due to the socioeconomic development and adoption of comprehensive control measures focusing on mass chemotherapy in the past decade.


Assuntos
Doenças Parasitárias/epidemiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , China/epidemiologia , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Prevalência , Estudos de Amostragem
8.
Artigo em Inglês | MEDLINE | ID: mdl-18244766

RESUMO

In this paper, we propose a novel fuzzy logic controller, called linguistic hedge fuzzy logic controller, to simplify the membership function constructions and the rule developments. The design methodology of linguistic hedge fuzzy logic controller is a hybrid model based on the concepts of the linguistic hedges and the genetic algorithms. The linguistic hedge operators are used to adjust the shape of the system membership functions dynamically, and ran speed up the control result to fit the system demand. The genetic algorithms are adopted to search the optimal linguistic hedge combination in the linguistic hedge module, According to the proposed methodology, the linguistic hedge fuzzy logic controller has the following advantages: 1) it needs only the simple-shape membership functions rather than the carefully designed ones for characterizing the related variables; 2) it is sufficient to adopt a fewer number of rules for inference; 3) the rules are developed intuitionally without heavily depending on the endeavor of experts; 4) the linguistic hedge module associated with the genetic algorithm enables it to be adaptive; 5) it performs better than the conventional fuzzy logic controllers do; and 6) it can be realized with low design complexity and small hardware overhead. Furthermore, the proposed approach has been applied to design three well-known nonlinear systems. The simulation and experimental results demonstrate the effectiveness of this design.

9.
IEEE Trans Neural Netw ; 8(6): 1545-56, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-18255755

RESUMO

The cerebellar model articulation controller (CMAC) neural network has the advantages of fast convergence speed and low computation complexity. However, it suffers from a low storage space utilization rate on weight memory. In this paper, we propose a direct weight address mapping approach, which can reduce the required weight memory size with a utilization rate near 100%. Based on such an address mapping approach, we developed a pipeline architecture to efficiently perform the addressing operations. The proposed direct weight address mapping approach also speeds up the computation for the generation of weight addresses. Besides, a CMAC hardware prototype used for color calibration has been implemented to confirm the proposed approach and architecture.

10.
Artigo em Inglês | MEDLINE | ID: mdl-18255886

RESUMO

In this paper, a tree-based approach is proposed to design the fuzzy logic controller. Based on the proposed methodology, the fuzzy logic controller has the following merits: the fuzzy control rule can be extracted automatically from the input-output data of the system and the extraction process can be done in one-pass; owing to the fuzzy tree inference structure, the search spaces of the fuzzy inference process are largely reduced; the operation of the inference process can be simplified as a one-dimensional matrix operation because of the fuzzy tree approach; and the controller has regular and modular properties, so it is easy to be implemented by hardware. Furthermore, the proposed fuzzy tree approach has been applied to design the color reproduction system for verifying the proposed methodology. The color reproduction system is mainly used to obtain a color image through the printer that is identical to the original one. In addition to the software simulation, an FPGA is used to implement the prototype hardware system for real-time application. Experimental results show that the effect of color correction is quite good and that the prototype hardware system can operate correctly under the condition of 30 MHz clock rate.

11.
Appl Opt ; 18(20): 3510-2, 1979 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-20216633

RESUMO

Wavelength and temperature-dependent characteristics of silicon P-I-N laser detectors are studied using the modified Baraff theory. Both the electron or hole injection effect and photogeneration effect are considered in the calculation of the power spectral density of multiplication noise and efficiencies. The results thus obtained are compared with previous papers where the photogeneration effect was neglected.

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