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1.
Chem Biodivers ; 20(4): e202300085, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36898981

RESUMO

Cardiovascular diseases (CVDs) are a major global health concern, and oxidative stress is known to play a central role in their pathogenesis. The identification of new agents capable of inhibiting oxidative stress presents a promising strategy for preventing and treating CVDs. Natural products and their derivatives offer a valuable source for drug discovery, and isosteviol, a readily available natural product, is known to exhibit cardioprotective effects. In this study, 22 new D-ring modified isosteviol derivatives were synthesized and evaluated for their cardioprotective effect in vivo using the zebrafish cardiomyopathy model. The findings revealed that derivative 4e exhibited the most potent cardioprotective effect, surpassing its parent compound isosteviol and the positive drug levosimendan. At 1 µM, derivative 4e significantly protected the cardiomyocytes from injury, while at 10 µM it effectively maintained normal heart phenotypes, preventing cardiac dysfunction in zebrafish. Further investigation demonstrated that 4e protected cardiomyocytes from oxidative stress-induced damage by inhibiting reactive oxygen species overaccumulation, activating superoxide dismutase 2 expression, and enhancing the endogenous antioxidant defense system. These results suggest that isosteviol derivatives, particularly 4e, have the potential to serve as a novel class of cardioprotective agents for the prevention and treatment of CVDs.


Assuntos
Cardiotônicos , Diterpenos do Tipo Caurano , Estresse Oxidativo , Animais , Cardiotônicos/farmacologia , Cardiotônicos/uso terapêutico , Diterpenos do Tipo Caurano/farmacologia , Diterpenos do Tipo Caurano/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Peixe-Zebra
2.
J Med Chem ; 67(8): 6749-6768, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38572607

RESUMO

Cardiovascular diseases (CVDs) persist as the predominant cause of mortality, urging the exploration of innovative pharmaceuticals. Mitochondrial dysfunction stands as a pivotal contributor to CVDs development. Sirtuin 3 (SIRT3), a prominent mitochondrial deacetylase known for its crucial role in protecting mitochondria against damage and dysfunction, has emerged as a promising therapeutic target for CVDs treatment. Utilizing isosteviol, a natural ent-beyerene diterpenoid, 24 derivatives were synthesized and evaluated in vivo using a zebrafish model, establishing a deduced structure-activity relationship. Among these, derivative 5v exhibited significant efficacy in doxorubicin-induced cardiomyopathy in zebrafish and murine models. Subsequent investigations revealed that 5v selectively elevated SIRT3 expression, leading to the upregulation of SOD2 and OPA1 expression, effectively preventing mitochondrial dysfunction, mitigating oxidative stress, and preserving cardiomyocyte viability. As a novel structural class of SIRT3 activators with robust therapeutic effects, 5v emerges as a promising candidate for further drug development.


Assuntos
Cardiotônicos , Diterpenos do Tipo Caurano , Desenho de Fármacos , Sirtuína 3 , Peixe-Zebra , Animais , Sirtuína 3/metabolismo , Sirtuína 3/antagonistas & inibidores , Diterpenos do Tipo Caurano/farmacologia , Diterpenos do Tipo Caurano/síntese química , Diterpenos do Tipo Caurano/química , Diterpenos do Tipo Caurano/uso terapêutico , Cardiotônicos/farmacologia , Cardiotônicos/síntese química , Cardiotônicos/química , Cardiotônicos/uso terapêutico , Relação Estrutura-Atividade , Camundongos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Humanos , Estresse Oxidativo/efeitos dos fármacos , Doxorrubicina/farmacologia
3.
Fitoterapia ; 169: 105616, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37479119

RESUMO

Glutamate-induced oxidative stress is well-known to play a crucial role in the development of neurodegenerative diseases, such as stroke. Genipin, a natural iridoid compound, has demonstrated potential neuroprotective properties but is unstable in physiological conditions. The present study aimed to develop new derivatives of genipin that exhibit improved stability and activity for the treatment of stroke. Nineteen new derivatives were thus designed and synthesized. Their neuroprotective effect against glutamate-induced injury was evaluated in HT22 cells. Among the newly synthesized derivatives, 3e demonstrated significantly greater neuroprotection and improved stability compared to genipin. Specifically, 0.01 µM of 3e was found to effectively attenuate glutamate-induced oxidative damage by inhibiting ROS over-accumulation, reducing MDA content, and restoring the endogenous antioxidative system. Further investigation revealed that 3e inhibited oxidative stress by downregulating the phosphorylation levels of p38 MAPK and activating Nrf2 and HO-1 proteins. These results suggested that 3e has the potential to serve as a promising candidate for the treatment of stroke by protecting against glutamate-induced oxidative stress.


Assuntos
Ácido Glutâmico , Fármacos Neuroprotetores , Ácido Glutâmico/toxicidade , Ácido Glutâmico/metabolismo , Fármacos Neuroprotetores/farmacologia , Linhagem Celular , Estrutura Molecular , Estresse Oxidativo , Iridoides/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo
4.
Front Microbiol ; 14: 1240471, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37840739

RESUMO

Flavobacterium columnare is the causative agent of columnaris disease in freshwater fish. Columnaris disease can cause heavy economic losses in aquaculture. In this study, whole-genome sequencing was used to characterize this pathogen. F. columnare isolate AH-01 had a circular chromosome and plasmid that encoded a total of 3,022 genes. Isolate GX-01 only had a circular chromosome and encoded 2,965 genes. Genomic islands, prophage regions, and CRISPR/Cas systems were identified in both genomes. Both genomes presented evidence of gene variation and horizontal transfer, both of which are the essential components of genetic diversity, genome plasticity, and functional evolution. Single-gene phylogeny and comparative genome analyses were performed to investigate the variation and evolution of this pathogen. Genetic analysis of 16S rRNA and housekeeping gene sequences significantly clustered 55 F. columnare isolates into four clades. The intragroup identity of the 16S rRNA gene exceeded 99%, while the intergroup identity was below the species delineation threshold. We discovered significant translocation, inversion, and rearrangement events that influenced local synteny within each group. Notably, the observed alignments varied considerably among all the studied groups. The core genomes of all strains with available sequences comprised 747 genes, corresponding to approximately 25% of the genome. Core genome multilocus sequence typing, genome-wide orthology and phylogenetic analyses, and average nucleotide identity suggested that the currently existing F. columnare was an assemblage of several distinct species, with levels of divergence at least equivalent to those between recognized bacterial species. The present investigation provided genomic evidence of gene variation and horizontal transfer, which were the basis of genetic diversity, genome plasticity, and functional evolution. The findings supported a proposed new taxonomic perspective on F. columnare.

5.
Ann Hum Biol ; 35(3): 349-54, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18568598

RESUMO

This study included 17 401 normal Han urban children aged 1-20 years from five cities in China in 2005. The skeletal maturity scores were assessed by the Tanner-Whitehouse 3 (TW3) method, and the smoothed centiles curves of scores (TW3-Chinese RUS and TW3-Chinese Carpal) were calculated using the LMS method. The skeletal maturity of the Chinese is approximately the same as Europeans in childhood, but the extent of TW3-RUS skeletal maturity advance in puberty and the ages of complete maturity of TW-Carpals are evidently more advanced in the Chinese.


Assuntos
Determinação da Idade pelo Esqueleto/normas , Desenvolvimento Ósseo , Adolescente , Adulto , Fatores Etários , Povo Asiático/estatística & dados numéricos , Calibragem , Criança , Pré-Escolar , China , Protocolos Clínicos/normas , Feminino , Ossos da Mão/crescimento & desenvolvimento , Humanos , Lactente , Masculino , Padrões de Referência , Valores de Referência , Fatores Sexuais
6.
Zhonghua Yi Xue Za Zhi ; 88(31): 2198-200, 2008 Aug 12.
Artigo em Zh | MEDLINE | ID: mdl-19080671

RESUMO

OBJECTIVE: To investigate the relationship of certain skeletal maturity indicators of hand and wrist with adolescent growth spurt. METHODS: 14 757 normal urban children, 7373 boys and 7384 girls, aged 7 - 20, all of Han nationality, from Shanghai, Guangzhou, Wenzhou, Dalian, and Shijiazhuang underwent measurement of height and weight, and left wrist anterior-posterior radiography. The incremental curve was fitted graphically according to the differences between the means for height at series ages. The ages of attainment of eleven skeletal indicators were defined by regression analysis for middle phalange 3, radius, and adductor sesamoid of the first finger. RESULTS: The accelerative phase of adolescent growth spurt was accompanied by becoming square of middle phalange 3 and the appearance of adductor sesamoid of the first finger. Peak growth velocity (PGV) was reached at about the time of epiphysis capping in middle phalange 3 and ossification of the adductor sesamoid of first finger. Decelerated phase of growth was indicated by the beginning of epiphysis fusion in radius and full maturity in adductor sesamoid of first finger. When the epiphysis of middle phalange 3 and the half of epiphysis of radius were respectively fused with their diaphyses, the growth spurt was ended. CONCLUSION: Certain skeletal maturity indicators of hand and wrist can be used to indicate the period of adolescent growth that a child has reached.


Assuntos
Desenvolvimento Ósseo , Ossos do Carpo/crescimento & desenvolvimento , Falanges dos Dedos da Mão/crescimento & desenvolvimento , Adolescente , Ossos do Carpo/diagnóstico por imagem , Criança , China , Feminino , Falanges dos Dedos da Mão/diagnóstico por imagem , Humanos , Masculino , Radiografia , Análise de Regressão
7.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 17(3): 177-9, 2005 Mar.
Artigo em Zh | MEDLINE | ID: mdl-15760535

RESUMO

OBJECTIVE: To study the changes in humoral immunological function and their clinical significance in cerebral hemorrhage. METHODS: Among 115 cases of cerebral hemorrhage, there was low volume bleeding in 39 case, middle volume in 37 cases, and large volume in 39 cases. The ratios of CD19+-CD25+ and CD19+-CD25-B lymphocytes were determined by flow cytometry, and the content of IgA, IgG, IgM, and complement C3 were determined with scattered turbidimetry. The changes in humoral immunological function were compared in patients with different degrees of hemorrhage, and their variation in acute and recovery stages of disease were respectively assessed. RESULTS: The ratios of CD19+-CD25+and CD19+-CD25-B lymphocyte, and the levels of IgA, IgG, IgM, and C3 were higher than those of controls (all P<0.05). The ratios of CD19+-CD25+ and CD19+-CD25- B lymphocyte, and the contents of IgA, IgG,IgM and C3 were increased with the increase in amount of hemorrhage(all P<0.05). The ratios of CD19+-CD25+ and CD19+-CD25-B lymphocytes in recovery stage were lower than those in acute stage (all P<0.05). CONCLUSION: There are activations of humoral immunological functions in cerebral hemorrhage. The more abundant in hemorrhage and the severer in disease, the more predominant in the changes in humoral immunological functions.


Assuntos
Formação de Anticorpos/imunologia , Hemorragia Cerebral/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Complemento C3/imunologia , Feminino , Humanos , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Masculino , Pessoa de Meia-Idade
8.
Exp Ther Med ; 7(1): 149-154, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24348781

RESUMO

The aim of this study was to investigate the frequency of circulating natural killer T (NKT) cells and regulatory T cells (Tregs), as well as serum cytokine profiles, in adult chronic primary immune thrombocytopenia (ITP). The frequency of circulating T cell receptor (TCR) Vα24+Vß11+CD3+ NKT cells and CD4+CD25+CD127-/low Tregs was measured using multi-color flow cytometry. The serum concentrations of 11 cytokines were determined with a cytometric bead assay. The frequency of circulating NKT cells in patients with ITP was 0.13±0.03%, whereas the frequency in healthy controls was 0.07±0.01% of CD3+ (P>0.05). However, the frequency of NKT cells in patients with ITP with platelet counts ≤20×109/l (0.22±0.05%) was significantly higher than that in patients with platelet counts >20×109/l (0.05±0.01%; P<0.05) and that in healthy controls (0.07±0.01%; P<0.05). The frequency of peripheral Tregs was comparable between patients with ITP (3.97±0.44% of CD4+) and healthy controls (3.69±0.31%; P>0.05). No significant differences were observed in the serum concentrations of 11 cytokines between patients with ITP and healthy controls, despite the fact that the serum levels of interleukin (IL)-12p70, IL-8, IL-4, interferon (IFN)-γ and tumor necrosis factor (TNF)-α in patients with ITP were higher than those in the healthy controls. The platelet count was negatively correlated with the frequency of circulating NKT cells in chronic ITP. These results indicate that NKT cells may be involved in ITP with severe thrombocytopenia, and NKT and Tregs may be important in cytokine deregulation in chronic ITP.

9.
Exp Ther Med ; 5(1): 209-214, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23251270

RESUMO

The aim of the present study was to evaluate the predictive efficiency of mean platelet volume (MPV) and platelet size deviation width (PDW) for bone marrow failure (BMF) in thrombocytopenic patients. Platelet count, MPV and PDW data were retrieved from the records of 574 unselected thrombocytopenic patients from between March 2010 and March 2011, of which 182 patients with a platelet count <20×10(9)/l were excluded from further study. A total of 392 valid thrombocytopenic patients were included in the present study and divided into two groups: 124 patients with idiopathic thrombocytopenia purpura (ITP) and 268 with BMF. The predictive efficiency of MPV and PDW were tested for the diagnosis of BMF. Significant differences were observed in the age distribution, platelet count, MPV and PDW between the ITP and BMF groups. The platelet count was positively correlated with MPV and PDW in the patients with ITP but not BMF. The negative-predictive values of MPV and PDW for BMF were 59.3 and 58.9%, respectively, with an MPV threshold of ≥11.0 fl and a PDW threshold of <16.0%. The positive-predictive values of MPV and PDW for BMF were 88.4 and 83.9%, respectively, with an MPV threshold <8.0 fl and a PDW threshold ≥17.5%. The areas under the curves (AUCs) of MPV and PDW were 0.281 and 0.700, respectively, for the diagnosis of BMF. The negative and positive-predictive values of MPV for BMF at different thresholds were not as conclusive as described in previous studies. MPV and PDW do not have sufficient specificity and sensitivity for the diagnosis of BMF in thrombocytopenic patients.

10.
ISRN Radiol ; 2013: 874570, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24967289

RESUMO

Rationale and Objective. Large studies have previously been performed to set up a Chinese bone age reference, but it has been difficult to compare the maturation of Chinese children with populations elsewhere due to the potential variability between raters in different parts of the world. We re-analysed the radiographs from a large study of normal Chinese children using an automated bone age rating method to establish a Chinese bone age reference, and to compare the tempo of maturation in the Chinese with other populations. Materials and Methods. X-rays from 2883 boys and 3143 girls aged 2-20 years from five Chinese cities, taken in 2005, were evaluated using the BoneXpert automated method. Results. Chinese children reached full maturity at the same age as previously studied Asian children from Los Angeles, but 0.6 years earlier than Caucasian children in Los Angeles. The Greulich-Pyle bone age method was adapted to the Chinese population creating a new bone age scale BX-China05. The standard deviation between BX-China05 and chronologic age was 1.01 years in boys aged 8-14, and 1.08 years in girls aged 7-12. Conclusion. By eliminating rater variability, the automated method provides a reliable and efficient standard for bone age determination in China.

11.
Zhonghua Er Ke Za Zhi ; 46(11): 851-5, 2008 Nov.
Artigo em Zh | MEDLINE | ID: mdl-19099904

RESUMO

OBJECTIVE: The determination of skeletal maturity has an important role in pediatric clinical practice, especially in relation to endocrinological problems and growth disorders, and it is frequently useful in diagnosis and monitoring treatment. It has been suggested that the difference between radius, ulna and short bonse (RUS) and carpal may be of differential diagnostic significance. However, no data on comparison among bone ages of Chinese children are available. The differences between TW3-Chinese RUS (TW3-C RUS) and TW3-Chinese Carpal (TW3-C Carpal) bone age of Chinese children were observed in this study to provide references for skeletal development estimation. METHODS: Totally 9408 Han healthy children (5066 boys, 4302 girls) aged 1.5 - 13.5 years from 5 cities of China were enrolled in this study. The bone ages of the children were estimated by TW3-C RUS and TW3-C Carpal. The Z score curves of the differences between them were fitted by BCPE distribution and the goodness-of-fit of Box-Cox power exponential distribution (BCPE) models were assessed by Q-test and percents of cases of sample below the fitted percentile curves. RESULTS: The means of the differences between TW3-C RUS and TW3-C Carpal were -0.19 - 0.17 over the age 2.0 - 13.5 years in boys and -0.12 - 0.13 from age 1.5 - 11.5 years in girls. The standard deviations were respectively 0.47 - 1.01 years for boys and 0.49 - 0.82 years for girls. The degrees of freedom, with respect to the parameter curves from BCPE distribution, were selected and the percentile curves were fitted by BCPE. The differences between percents of cases below the fitted percentile curves and expected values were all under 0.66%, exception of difference for 90th percentile in girls. CONCLUSIONS: The differences between TW3-C RUS and TW3-C Carpal varied with age, the standard deviations increased gradually before 4.5 years of age in boys and 4 years of age in girls, and afterwards the variations decreased steadily until the TW3-C Carpal has reached full maturity. However, there was sex diversity in the extent of the variations. The differences between TW3-C RUS and TW3-C Carpal for boys were evidently greater than that for girls. The sex difference decreased progressively after 10 years. The proposed Z scores curves charts should provide reference for clinical practice.


Assuntos
Determinação da Idade pelo Esqueleto/estatística & dados numéricos , Desenvolvimento Ósseo , Ossos do Carpo/anatomia & histologia , Adolescente , Povo Asiático , Criança , Pré-Escolar , China , Feminino , Humanos , Lactente , Masculino , Rádio (Anatomia) , Valores de Referência , Ulna , População Urbana
12.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 11(4): 398-404, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12962571

RESUMO

To establish reference values of various immunophenotypic markers in B lymphocyte population in healthy Chinese adults and build background information for accurate interpretation of B cell immunophenotyping data in clinical practice, peripheral blood from 41 healthy adults were collected separately into test tubes containing EDTA-K(2) and stored in room temperature no more than 24 hours before analysis. Whole blood lysis technique and multiparameter flow cytometry were applied to immunophenotype B cells gated on CD19/SSC dot-plot. The results showed that CD22, CD20, CD62L, CD40, CD24, CD79b, CD79a, and FMC-7 were almost positive in the circulating B cell population, whereas CD11a, CD80, CD103, CD10, CD40L, CD54, CD95L, CD86, and CD95 were almost negative in the peripheral blood B lymphocytes. CD18, CD44, CD23, CD5, CD11c and CD43 were positive in different B cell subpopulations. 78% of B cells were IgD positive and ratio kappa/lambda was 1.26. The significance of all these markers in the differential diagnosis of lymphoproliferative diseases was discussed. The conclusion is that it is necessary to consider the qualitative and quantitative levels of expression of various markers in normal B cell population in order to accurately interpret the pathological immunophenotypic data in clinical practice. It is also important to note the immunotypic differences of B cells between Chinese and Western populations.


Assuntos
Linfócitos B/imunologia , Citometria de Fluxo/métodos , Leucemia Linfocítica Crônica de Células B/imunologia , Linfoma/imunologia , Adulto , Idoso , Antígenos CD5/análise , Feminino , Humanos , Imunofenotipagem , Molécula 1 de Adesão Intercelular/análise , Masculino , Pessoa de Meia-Idade , Receptores de IgE/análise
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