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1.
Front Surg ; 9: 860300, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35529907

RESUMO

Introduction: This study aimed to evaluate the effect of arthroscopic treatment of popliteus tendinitis via an auxiliary extreme lateral approach and to investigate the pathogenesis and treatment of popliteus tendinitis. Materials and Methods: From 2016 to 2020, arthroscopic popliteus tendon ablation was performed in 15 patients (15 knees) with popliteus tendinitis via an auxiliary extreme lateral approach. Clinical outcomes were assessed using the Lysholm knee scoring scale, the Tegner score, the International Knee Documentation Committee (IKDC) score and the visual analogue scale (VAS) pain score at the 24-month follow-up after surgery. Results: A total of 15 patients (mean age, 51.1 ± 7.1 years) were included. They had a mean body mass index of 23.8 ± 2.1 kg/m2. The minimum follow-up period was 24 months. Comparing the postoperative state to the preoperative state, the mean postoperative Lysholm score, Tegner score, and IKDC score improved significantly from 70.0 ± 5.0, 3.0 ± 0.9, and 62.3 ± 5.5 to 89.3 ± 4.2, 4.6 ± 0.61, and 80.5 ± 4.4, respectively (p < 0.01). The preoperative VAS score for pain improved from 6.4 ± 0.5 to 0.9 ± 0.4 (p < 0.01). No patients were lost to follow-up. Conclusions: Following arthroscopic-assisted treatment, all the patients with popliteus tendinitis achieved satisfactory clinical outcomes in terms of pain relief and improved function. Level of Evidence: Level IV.

2.
Zhonghua Yi Xue Za Zhi ; 99(15): 1142-1146, 2019 Apr 16.
Artigo em Chinês | MEDLINE | ID: mdl-31006216

RESUMO

Objective: To evaluate the tumor burden reducing efficacy and safety of transcatheter arterial embolization (TAE) combined with octreotide LAR on neuroendocrine tumor liver metastasis (NETLM). Methods: Twenty-nine NETLM patients treated in the First Affiliated Hospital of Sun Yat-sen University from October 2014 to August 2018 were retrospectively recruited, including 12 males and 17 females. The mean age was 25-69(50±11) years. All patients were histologically proved as well-differentiated NET liver metastasis. Seventeen patients underwent combined treatment of TAE plus octreotide LAR (combined group) and 12 patients treated with only octreotide LAR (control group). Response of hepatic lesions were assessed according to RECIST 1.1. Objective response rates (ORR) of two groups were compared and analyzed. Safety and tolerance to TAE were also evaluated. Results: There were 13 PR and 4 SD in combined group, but only 1 PR and 9 PD in the control group. The ORR between the two groups were significantly different (13/17 vs 1/12, P<0.01).The main complication post TAE was post embolization syndrome, including abdominal pain (12/17), vomiting (6/17), fever (4/17), elevated transaminase (8/17) and bilirubinemia (3/17). Tumor lysis syndrome was observed in one patient. Conclusion: Compared to administration of octreotide LAR, TAE combined with octreotide LAR can effectively reduce tumor burden in patients with NETLM. TAE is safe and well-tolerated.


Assuntos
Neoplasias Hepáticas/secundário , Tumores Neuroendócrinos , Adulto , Feminino , Humanos , Masculino , Octreotida , Estudos Retrospectivos , Resultado do Tratamento , Carga Tumoral
3.
AMB Express ; 8(1): 193, 2018 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-30564983

RESUMO

Tetramethylpyrazine (TMP) with significant protective effects on cardiovascular is the active ingredient of traditional Chinese medicine Rhizoma Chuanxiong (RC). However, many studies have reported the low content of TMP in RC. The endophytes of medicinal plants have the biosynthetic potential to produce the same or similar active metabolites as the host, while few reports were conducted to explore the endophytic bacteria of Ligusticum chuanxiong Hort. and its productive capacity for the important ingredient TMP. The present paper focuses on the isolation and identification of TMP producing endophytic bacteria from RC. In this study, the endophytic bacteria were isolated from the rhizome of Ligusticum chuanxiong Hort. (Umbelliferae). Yeast extract peptone glucose medium (YP) was used for fermentation medium (37 °C, 220 rpm agitation, 144 h). GC and GC/MS were performed to determine and verify the product, the fermentation characteristics were investigated. Morphological observation, physiological and biochemical indexes combining with 16S rRNA sequence analysis were carried out to identify the endophytic bacteria. As a result, five strains of endophytic Bacillus subtilis were firstly isolated and identified from RC, named as LB3, LB3-2-1, LB6-2, LB4, LB5 respectively. All five strains of endophytic B. subtilis produced TMP, while LB5 had the highest production of 10.69 g/L at the 144 h fermentation. This work demonstrates the fact that the endophytic B. subtilis of RC can produce a high level of TMP, indicating the endophytic B. subtilis might play a role in the accumulation of TMP during the growth period of RC.

4.
Mater Sci Eng C Mater Biol Appl ; 93: 958-967, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30274133

RESUMO

Here we report the extreme toxicity in vitro of Bi(OH)3 and α-Bi2O3 nanoparticles (NPs), obtained through a facile synthesis with an average single particle size of 6-10 nm, tested on malignant gliosarcoma 9L and MCF-7 human breast cancer cells. For both nanomaterials, clonogenic assays reveal a mortality of over 90% in 9L and MCF-7 cells for a concentration of 50 µg/mL after incubation for 24 h. Moreover, the NPs show a significant mortality of up to 60% in the malignant cells at the very low concentration of 6.25 µg/mL. In contrast, at the same concentration, the nanomaterials exhibit no noticeable mortality towards normal Madin-Darby canine kidney cells. The internalisation of the NPs was demonstrated using flow cytometry and confocal microscopy was used to investigate when the loss of cell viability starts. The NPs show a faster cell death in 9L cells compared with MCF-7 cells, demonstrated via the identification of apoptosis through increased sub G1 levels after 24 h of NP incubation. Cleavage is identified as the main apoptotic nuclear morphology in 9L, which suggests the presence of reactive oxygen species.


Assuntos
Apoptose/efeitos dos fármacos , Bismuto/farmacologia , Citotoxinas/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Nanopartículas , Animais , Bismuto/química , Citotoxinas/química , Cães , Feminino , Humanos , Células MCF-7 , Células Madin Darby de Rim Canino
5.
J Viral Hepat ; 25(8): 904-910, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29582521

RESUMO

The underlying mechanism of coexistence of hepatitis B surface antigen (HBsAg) and hepatitis B surface antigen antibody (anti-HBs) is still controversial. To identify the host genetic factors related to this unusual clinical phenomenon, a two-stage study was conducted in the Chinese Han population. In the first stage, we performed a case-control (1:1) age- and gender-matched study of 101 cases with concurrent HBsAg and anti-HBs and 102 controls with negative HBsAg and positive anti-HBs using whole exome sequencing. In the second validation stage, we directly sequence the 16 exons on the OAS3 gene in two dependent cohorts of 48 cases and 200 controls. Although, in the first stage, a genome-wide association study of 58,563 polymorphism variants in 101 cases and 102 controls found no significant loci (P-value ≤ .05/58563), and neither locus achieved a conservative genome-wide significance threshold (P-value ≤ 5e-08), gene-based burden analysis showed that OAS3 gene rare variants were associated with the coexistence of HBsAg and anti-HBs. (P-value = 4.127e-06 ≤ 0.05/6994). A total of 16 rare variants were screened out from 21 cases and 3 controls. In the second validation stage, one case with a stop-gained rare variant was identified. Fisher's exact test of all 149 cases and 302 controls showed that the rare coding sequence mutations were more frequent in cases vs controls (P-value = 7.299e-09, OR = 17.27, 95% CI [5.01-58.72]). Protein-coding rare variations on the OAS3 gene are associated with the coexistence of HBsAg and anti-HBs in patients with chronic HBV infection in Chinese Han population.


Assuntos
2',5'-Oligoadenilato Sintetase/genética , Variação Genética , Anticorpos Anti-Hepatite B/sangue , Antígenos de Superfície da Hepatite B/sangue , Hepatite B Crônica/genética , Hepatite B Crônica/patologia , Adulto , Povo Asiático , Etnicidade , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência de DNA
6.
Genet Mol Res ; 14(4): 15399-411, 2015 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-26634505

RESUMO

Heterosis has greatly contributed to conventional plant breeding and is widely used to increase crop plant productivity. However, although some studies have explored the mechanisms of heterosis at the genomic and transcriptome level, these mechanisms still remain unclear. The growth and development of maize seedlings and immature embryos have an important impact on subsequent production. This study investigated differentially expressed genes (DEGs) between parents and reciprocal hybrids in the seedling leaves, roots, and immature embryo 15 days after pollination using amplified fragment length polymorphism (AFLP)-based transcript profiling (cDNA-AFLP). We isolated 180, 170, and 108 genes from the leaves, roots, and immature embryos, respectively, that were differentially expressed between hybrids and parents. Sequencing and functional analysis revealed that 107 transcript-derived fragments in the roots and leaves and 90 in the immature embryos were involved in known functions, whereas many DEGs had roles in plant growth and development, photosynthesis, signal transduction, and seed germination. Quantitative reverse-transcription polymerase chain reaction analysis of relative expression levels between reciprocal hybrids and both parental genotypes of selected genes produced results that were consistent with cDNA-AFLP. We validated the expression patterns of 15 selected genes related to heterosis formation and revealed that most showed non-additive expression in one or both hybrids, including dominant, underdominant, and overdominant expression. This indicates that gene-regulatory interactions among parental alleles play an important role in heterosis during the early developmental stages of maize.


Assuntos
Quimera , Perfilação da Expressão Gênica , Hibridização Genética , Transcriptoma , Zea mays/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Germinação/genética , Vigor Híbrido/genética , Endogamia , Reprodutibilidade dos Testes
7.
Genet Mol Res ; 13(4): 8458-68, 2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-25366740

RESUMO

Heterosis is the superior performance of heterozygous individuals and has been widely exploited in plant breeding, although the underlying regulatory mechanisms still remain largely elusive. To understand the molecular basis of heterosis in maize, in this study, roots and leaves at the seedling stage and embryos and endosperm tissues 15 days after fertilization of 2 elite hybrids and their parental lines were used to estimate the levels and patterns of cytosine methylation by the methylation-sensitive amplification polymorphism method. The relative total methylation levels were lower in all the tissues of all hybrids than their corresponding mid-parent values, and the number of demethylation events was higher in the hybrids. These results implied that the decreasing trend and demethylation in hybrids relative to their parents may enable the derepression and possibly expression of many genes that were associated with the phenotypic variation in hybrids. To further analyze the observed methylation pattern changes, a total of 63 differentially displayed DNA fragments were successfully sequenced. Basic Local Alignment Search Tool analysis showed that 11 fragments shared similarity with known functional proteins in maize or other plant species, including metabolism, transposon/retrotransposon, development, stress response, and signal transduction, which indicated that these genes might play a significant role in maize hybrid vigor.


Assuntos
Metilação de DNA , Regulação da Expressão Gênica de Plantas , Vigor Híbrido , Hibridização Genética , Zea mays/genética , Endogamia
8.
Genet Mol Res ; 13(4): 9019-23, 2014 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-25366792

RESUMO

Hu sheep is one of the most important species in China; it is also listed as one of the 78 nationally protected domestic animals by the Chinese government in 2000. The construction of cDNA expression library of Hu sheep is of great significance for protecting individual genomes, generating transgenic sheep, and conducting clinical research using cDNA from Hu sheep. In this study, the total RNA from the ear tissue of Hu sheep was extracted, and a cDNA expression library was constructed using the SMART(TM) technique. The titer of amplified cDNA library was 1.09 x 10(10) PFU/mL, the rate of recombination was above 91.6%, and the average size of fragments was 1.1 kb. This study has an important significance for the preservation of Hu sheep resources at the genome level.


Assuntos
DNA Complementar/genética , Espécies em Perigo de Extinção , Biblioteca Gênica , Ovinos/genética , Animais , China , Clonagem Molecular , Eletroforese em Gel de Ágar , RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
Genet Mol Res ; 13(3): 6126-34, 2014 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-25117371

RESUMO

We examined the influence of the promoter polymorphisms -250G/A (rs2070895) and -514C/T (rs1800588) in the human hepatic lipase (LIPC) gene on dyslipidemia and hypertensive disorders complicating pregnancy (HDCP) in a Chinese population. Clinically defined HDCP patients (N = 321) and healthy pregnant women (N = 331) were recruited and genotyped using polymerase chain reaction-restriction fragment length polymorphism for the two LIPC single nucleotide polymorphisms (SNPs). The results showed significant relationships between HDCP and triglycerides, apolipoprotein A1, and high-density lipoprotein cholesterol (P < 0.05), which confirmed that HDCP was accompanied by dyslipidemia. The results also demonstrated that in gestational hypertension (GH) patients, both total cholesterol (TC) and systolic blood pressure (SBP) levels were related to the two SNPs (P ≤ 0.004), although no significant association was found between HDCP and LIPC genotypes or alleles. Significant linkage disequilibrium of the two SNPs was found in both HDCP patients (R(2) = 0.867) and controls (R(2) = 0.91). Body mass index (BMI) was associated with -250G/A in women with mild preeclampsia (MPE) (P = 0.01). Carriers of the mutant homozygote -250AA genotype presented higher BMI in the MPE group. In conclusion, the LIPC -250G/A and -514C/T variants influenced TC and SBP levels in GH patients and the BMI level in the MPE group, although there was no evidence to validate an association between HDCP and LIPC allele, genotype, or haplotype frequencies.


Assuntos
Povo Asiático/genética , Estudos de Associação Genética , Hipertensão Induzida pela Gravidez/genética , Lipase/genética , Polimorfismo de Nucleotídeo Único , Adulto , Alelos , Pressão Sanguínea , Estudos de Casos e Controles , China , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Hipertensão Induzida pela Gravidez/diagnóstico , Lipídeos/sangue , Lipoproteínas/sangue , Gravidez , Risco
10.
J Nanosci Nanotechnol ; 12(6): 4724-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22905522

RESUMO

The structural evolution of nanocrystalline TiO2 was studied by X-ray diffraction (XRD) and the Rietveld refinement method (RRM). TiO2 powders were prepared by the sol-gel technique. Post annealing of as-synthesized powders in the temperature range from 500 degrees C to 800 degrees C under air and argon atmospheres led to the formation of TiO2 nanoparticles with mean crystallite size in the range of 37-165 nm, based on the Rietveld refinement results. It was found that the phase structure, composition, and crystallite size of the resulting particles were dependent on not only the annealing temperature, but also the annealing atmosphere. Rietveld refinement of the XRD data showed that annealing the powders under argon atmosphere promoted the polymorphic phase transformation from anatase to rutile. Field emission scanning electron microscopy (FESEM) was employed to investigate the morphology and size of the annealed powders.


Assuntos
Cristalização/métodos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Titânio/química , Atmosfera , Dureza , Temperatura Alta , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Tamanho da Partícula , Transição de Fase , Pós , Propriedades de Superfície
11.
Phytomedicine ; 17(8-9): 626-34, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20096551

RESUMO

The antidiabetic actions of Paeoniae Radix involve stimulating glucose uptake and reducing glucose absorption. However, the importance of this herb in the transcriptional regulation of hepatic gluconeogenesis has not previously been investigated, although hepatic gluconeogenesis contributes the most to fasting hyperglycemia. Using rats with streptozotocin-induced diabetes and db/db mice, the dose- and time-dependent suppressive effects of the ethanol extract of Paeoniae Radix (PR-Et) on diabetic hyperglycemia and phosphoenopyruvate carboxykinase (PEPCK) transcription are first demonstrated. Second, by employing H4IIE cells, the inhibitory action of PR-Et on both dexamethasone- and 8-bromo-cAMP-induced-PEPCK expression was also confirmed without causing any cytotoxicity. In addition, this inhibitory effect could be sustained for over 24 h with repeated treatment. Most importantly, PR-Et's action was unaffected by either insulin desensitization or palmitate stimulation. Finally, paeonol and paeoniflorin, two well-known constituents in Paeoniae Radix, did not suppress PEPCK expression at testing concentration. In conclusion, it was clearly demonstrated that transcriptional inhibition of gluconeogenesis is one of the important antidiabetic actions of Paeoniae Radix. Future development of this herb as a dietary supplement or drug should bring substantial benefits for the diabetic population.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Gluconeogênese/efeitos dos fármacos , Hipoglicemiantes/uso terapêutico , Fígado/efeitos dos fármacos , Paeonia/química , Fosfoenolpiruvato Carboxiquinase (GTP)/metabolismo , 8-Bromo Monofosfato de Adenosina Cíclica , Acetofenonas/isolamento & purificação , Acetofenonas/farmacologia , Acetofenonas/uso terapêutico , Animais , Benzoatos/isolamento & purificação , Benzoatos/farmacologia , Benzoatos/uso terapêutico , Hidrocarbonetos Aromáticos com Pontes/isolamento & purificação , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Hidrocarbonetos Aromáticos com Pontes/uso terapêutico , Linhagem Celular , Dexametasona , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Expressão Gênica/efeitos dos fármacos , Gluconeogênese/genética , Glucosídeos/isolamento & purificação , Glucosídeos/farmacologia , Glucosídeos/uso terapêutico , Humanos , Hipoglicemiantes/isolamento & purificação , Hipoglicemiantes/farmacologia , Insulina/metabolismo , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monoterpenos , Ácido Palmítico/metabolismo , Fosfoenolpiruvato Carboxiquinase (GTP)/genética , Fitoterapia , Raízes de Plantas , Ratos , Ratos Sprague-Dawley
12.
J Nanosci Nanotechnol ; 9(2): 1474-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19441550

RESUMO

SnO2-carbon nanotube composites were prepared by chemical treatment of tin chloride salt mixed with carbon nanotubes, followed by heat-treatment at high temperature. Nanosize SnO2 particles were formed and embedded in a carbon nanotube matrix. TEM and HRTEM observation confirmed the homogeneous distribution of SnO2 nanoparticles. SnO2-carbon nanotube anodes demonstrated high lithium storage capacity and stable cyclability, which could be attributed to the nanosize SnO2 crystals and the formation of carbon nanotube networks in the electrode.

13.
BMC Mol Biol ; 7: 14, 2006 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-16600022

RESUMO

BACKGROUND: Glycogen Synthase Kinase-3 (GSK3) activity is repressed following insulin treatment of cells. Pharmacological inhibition of GSK3 mimics the effect of insulin on Phosphoenolpyruvate Carboxykinase (PEPCK), Glucose-6 Phosphatase (G6Pase) and IGF binding protein-1 (IGFBP1) gene expression. CAAT/enhancer binding protein alpha (C/EBPalpha) regulates these gene promoters in liver and is phosphorylated on two residues (T222/T226) by GSK3, although the functional outcome of the phosphorylation has not been established. We aimed to establish whether CEBPalpha is a link between GSK3 and these gene promoters. RESULTS: C/EBPalpha represses the IGFBP1 thymine-rich insulin response element (TIRE), but mutation of T222 or T226 of C/EBPalpha to non-phosphorylatable alanines has no effect on C/EBPalpha activity in liver cells (towards the TIRE or a consensus C/EBP binding sequence). Phosphorylation of T222/T226 is decreased by GSK3 inhibition, suggesting GSK3 does phosphorylate T222/226 in intact cells. However, phosphorylation was not altered by treatment of liver cells with insulin. Meanwhile C/EBPalpha activity in 3T3 L1 preadipocytes was enhanced by mutation of T222/T226 and/or S230 to alanine residues. Finally, we demonstrate that C/EBPalpha is a very poor substrate for GSK3 in vitro and in cells. CONCLUSION: The work demonstrates an important role for this domain in the regulation of C/EBPalpha activity in adipocytes but not hepatocytes, however GSK3 phosphorylation of these residues does not mediate regulation of this C/EBP activity. In short, we find no evidence that C/EBPalpha activity is regulated by direct phosphorylation by GSK3.


Assuntos
Proteína alfa Estimuladora de Ligação a CCAAT/biossíntese , Proteína alfa Estimuladora de Ligação a CCAAT/genética , Regulação da Expressão Gênica , Quinase 3 da Glicogênio Sintase/metabolismo , Treonina/química , Células 3T3-L1 , Adenoviridae , Adipócitos/metabolismo , Animais , Linhagem Celular , Linhagem Celular Tumoral , Biblioteca Gênica , Hepatócitos/metabolismo , Humanos , Insulina/metabolismo , Metabolismo dos Lipídeos , Camundongos , Modelos Biológicos , Mutação , Fosforilação , Estrutura Terciária de Proteína , RNA/metabolismo , Ratos , Elementos de Resposta , Ribonucleases/metabolismo , Especificidade por Substrato , Timina/metabolismo , Transfecção
14.
J Nanosci Nanotechnol ; 6(1): 77-81, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16573073

RESUMO

Uniform and aligned Nickel Oxide (NiO) nanotube bundles have been synthesized by a template process. Individual nanotubes are 60 microm long with a 200 nm outer diameter and wall thickness of 20-30 nm. The synthesis involved forming Ni(OH)2 nanotubes that were subsequently heated to 350 degrees C in order to fully convert the product to NiO nanotubes. NiO nanotube powder was used in lithium-ion cells for assessment of lithium storage ability and electrochemical performance. Discharge capacity of the NiO nanotube electrode was in excess of 30% higher than that of the standard NiO nanocrystalline powder electrode after 20 cycles. Impedance data suggests the NiO nanotube electrode provides more controlled and sustainable Li diffusion when compared to the NiO reference powder electrode system.


Assuntos
Nanoestruturas/química , Níquel/química , Fontes de Energia Elétrica , Eletroquímica/métodos , Íons , Lítio , Microscopia Eletrônica de Varredura , Potenciometria , Soluções , Difração de Raios X
15.
J Nanosci Nanotechnol ; 6(3): 713-8, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16573126

RESUMO

Single-walled carbon nanotube (SWNT) papers were successfully prepared by dispersing SWNTs in Triton X-100 solution, then filtered by PVDF membrane (0.22 microm pore size). The electrochemical behavior and the reversible hydrogen storage capacity of single-walled carbon nanotube (SWNT) papers have been investigated in alkaline electrolytic solutions (6 N KOH) by cyclic voltammetry, linear micropolarization, and constant current charge/discharge measurements. The effect of thickness and the addition of carbon black on hydrogen adsorption/desorption were also investigated. It was found that the electrochemical charge-discharge mechanism occurring in SWNT paper electrodes is somewhere between that of carbon nanotubes (physical process) and that of metal hydride electrodes (chemical process), and consists of a charge-transfer reaction (Reduction/Oxidation) and a diffusion step (Diffusion).


Assuntos
Eletroquímica/métodos , Hidrogênio , Nanotecnologia/métodos , Nanotubos de Carbono/química , Nanotubos de Carbono/ultraestrutura , Papel , Ultrafiltração/métodos , Absorção , Teste de Materiais , Tamanho da Partícula
16.
J Nanosci Nanotechnol ; 5(7): 1135-40, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16108440

RESUMO

The ionic conductivity of polyethylene oxide (PEO) based solid polymer electrolytes (SPEs) has been improved by the addition of nanosize ceramic powders (TiO2 and AL2O3). The PEO based solid polymer electrolytes were prepared by the solution-casting method. Electrochemical measurement shows that the 10 wt% TiO2 PEO-LiClO4 polymer electrolyte has the best ionic conductivity (about 10(-4) S cm(-1) at 40-60 degrees C). The lithium transference number of the 10 wt% TiO2 PEO-LiClO4 polymer electrolyte was measured to be 0.47, which is much higher than that of bare PEO polymer electrolyte. Ac impedance testing shows that the interface resistance of ceramic-added PEO polymer electrolyte is stable. Linear sweep voltammetry measurement shows that the PEO polymer electrolytes are electrochemically stable in the voltage range of 2.0-5.0 V versus a Li/Li+ reference electrode.


Assuntos
Nanotecnologia/métodos , Polietilenoglicóis/química , Polímeros/química , Óxido de Alumínio/química , Materiais Biocompatíveis , Cerâmica/química , Eletroquímica , Eletrólitos , Íons , Lítio/química , Microscopia Eletrônica de Transmissão , Modelos Químicos , Pós , Espectrofotometria , Propriedades de Superfície , Titânio/química
17.
Diabetes Obes Metab ; 7(5): 563-9, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16050949

RESUMO

Glucagon-like peptide-1 (GLP-1) is an important insulinotropic hormone with potential in the treatment of type 2 diabetes. However, the short biological half-life of the peptide after cleavage by dipeptidylpeptidase IV (DPP IV) is a major limitation. Inhibition of DPP IV activity and the development of resistant GLP-1 analogues is the subject of ongoing research. In this study, we determined cell growth, insulin content, insulin accumulation and insulin secretory function of a insulin-secreting cell line cultured for 3 days with either GLP-1, GLP-1 plus the DPP IV inhibitor diprotin A (DPA) or stable N-acetyl-GLP-1. Native GLP-1 was rapidly degraded by DPP IV during culture with accumulation of the inactive metabolite GLP-1(9-36)amide. Inclusion of DPA or use of the DPP IV-resistant analogue, N-acetyl-GLP-1, improved cellular function compared to exposure to GLP-1 alone. Most notably, basal and accumulated insulin secretion was enhanced, and glucose responsiveness was improved. However, prolonged GLP-1 treatment resulted in GLP-1 receptor desensitization regardless of DPP IV status. The results indicate that prevention of DPP IV action is necessary for beneficial effects of GLP-1 on pancreatic beta cells and that prolonged exposure to GLP-1(9-36)amide may be detrimental to insulin secretory function. These observations also support the ongoing development of DPP-IV-resistant forms of GLP-1, such as N-acetyl-GLP-1.


Assuntos
Dipeptidil Peptidase 4/fisiologia , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Células Secretoras de Insulina/efeitos dos fármacos , Insulina/metabolismo , Animais , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Dipeptidil Peptidase 4/metabolismo , Relação Dose-Resposta a Droga , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/metabolismo , Oligopeptídeos/farmacologia , Inibidores de Proteases/farmacologia , Ratos
18.
Poult Sci ; 84(2): 321-7, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15742970

RESUMO

A polycystic ovarian follicle (PCOF) syndrome associated with high baseline concentrations of progesterone (P4) without preovulatory luteinizing hormone (LH) surges has been reported in turkey hens. The PCOF syndrome could be induced in turkey hens by injecting P4 (0.33 mg/kg per d) daily early in the reproductive period for 10 to 12 d and then waiting 3 wk for the syndrome to develop. It was hypothesized that an arrest in laying associated with the PCOF syndrome could be induced by daily injection of P4 in restricted-fed broiler breeder hens. Hens were divided into 5 treatment groups and were injected subcutaneously daily with P4 in canola oil at dosages of 0, 0.17, 0.33, 0.5, and 1.5 mg/kg per d for 13 d, at 14 wk of egg production when they were 41 wk of age. Blood samples were collected on d 7 and 13 immediately before P4 injection. Oviductal and ovarian morphologies were measured at necropsy 1 d after the last P4 injection. Egg production rate was reduced by injection of P4 at dosages < 0.17 mg/kg per d. At dosages of 0.5 and 1.5 mg/kg per d, ovarian hierarchical follicles had regressed. None of the broiler breeder hens had the PCOF syndrome at necropsy, but a high incidence of hens holding hard-shelled uterine eggs for several days was observed. Concentrations of LH decreased with P4 injection at > 0.17 mg/kg per d, and P4 concentrations were increased with P4 injection at > 0.5 mg/kg per d. Estradiol-17beta (E2) concentrations were decreased at all P4 dosages. It was concluded that egg production rate was reduced by daily injection of P4 at dosages > 0.17 mg/kg per d, and egg production ceased and ovarian follicles and the oviduct regressed at dosages > 0.50 mg/kg per d. The PCOF syndrome, however, was not induced in restricted-fed broiler breeder hens by P4 injection.


Assuntos
Oviposição/efeitos dos fármacos , Progesterona/toxicidade , Animais , Galinhas , Relação Dose-Resposta a Droga , Estradiol/sangue , Feminino , Hormônio Luteinizante/sangue , Folículo Ovariano/efeitos dos fármacos , Ovário/efeitos dos fármacos , Oviductos/efeitos dos fármacos , Progesterona/sangue
19.
Poult Sci ; 83(12): 2051-8, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15615020

RESUMO

Young laying turkey hens ceased laying and developed a polycystic ovarian follicle (PCOF) syndrome 3 wk after injections of progesterone (P4) ceased. It was hypothesized that laying Japanese quail chronically injected with progesterone (P4) would respond with reduced or arrested egg production and altered ovarian morphology similar to that seen in turkeys expressing the PCOF syndrome, and could thus serve as a model to study the PCOF syndrome. To test these hypotheses, 6 trials were conducted with young photosensitive Japanese quail photostimulated to induce sexual maturity with either 24L:0D or 14L:10D at 6 or 8 wk of age, and used after 3 to 5 wk of egg production. The quail were injected once daily at dosages of 0, 0.17, 0.33, 0.5, 1.5, 3.0, or 4.5 mg of P4/kg per d, or twice daily at dosages of 0 and 1.5 mg of P4/kg for 8 to 14 d and were then necropsied 1 d after the last injection or after waiting an additional 8 to 14 d. During the injection period, egg production was not different among P4 dosages <1.5 mg of P4/kg per d, but decreased at dosages of 1.5 mg of P4/kg per d or greater. A decrease in egg production was found with twice daily injections of 1.5 mg of P4/kg. The decrease in egg production rate ceased and egg production resumed 5 to 7 d after the last injections of 3.0 and 4.5 mg of P4/kg per d or twice-daily injections of 1.5 mg of P4/kg. Compared with control hens, a high percentage of hens (from 12 to 75%) held a hard-shelled egg in the uterus during single daily injections at dosages of 3.0 and 4.5 mg of P4/kg per d and twice daily injections of 1.5 mg of P4/kg. Ovary and oviductal weights, and number of hierarchical follicles were not changed after chronic P4 injection, but more atretic follicles were found in hens at the end of 8 to 12 d of P4 injection. In conclusion, a decreasing egg production rate was induced by chronic P4 injection, but the decrease ceased and egg production resumed 5 to 7 d after the last injections in laying Japanese quail. Young quail hens, unlike young turkey hens, did not develop a PCOF-like syndrome after P4 injection.


Assuntos
Coturnix/fisiologia , Oviposição/efeitos dos fármacos , Progesterona/toxicidade , Animais , Peso Corporal/efeitos dos fármacos , Esquema de Medicação/veterinária , Feminino , Luz , Tamanho do Órgão/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Ovário/efeitos dos fármacos , Oviductos/efeitos dos fármacos , Doenças das Aves Domésticas/induzido quimicamente , Progesterona/administração & dosagem , Perus
20.
J Nanosci Nanotechnol ; 4(7): 861-6, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15570973

RESUMO

Nano-crystalline Co3O4 and CoO powders have been prepared by a spray pyrolysis approach. The effects of the reaction temperature and initial salts on the crystallinity and phase composition have been studied. Based on the TEM and XRD results, the crystal sizes were in the range of 1-10 nm. SEM and TEM observations also reveal that the nano-powders easily create micron-scale spherical agglomerates. The Co3O4 powders obtained by spraying nitrate solution at 500 degrees C show high specific surface area, which according to the BET method is 82.37 m2/g. The time/temperature phase diagram of cobalt oxides developed from XRD and DTA/TGA analyses shows the existence of a CoO phase at low and high temperature ranges when some specific preparation conditions are applied.


Assuntos
Nanotecnologia/métodos , Materiais Biocompatíveis/química , Cobalto/química , Temperatura Alta , Lítio/química , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Óxidos/química , Difração de Pó , Temperatura , Fatores de Tempo , Difração de Raios X
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