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1.
Artigo em Inglês | MEDLINE | ID: mdl-31580011

RESUMO

BACKGROUND: Main vessel (MV) stent deformation and overstretch caused by classical kissing balloon inflation (C-KBI) using two balloons with a longer overlapping in the MV for bifurcation lesions has caused a widespread concern. PURPOSE: This bench study tested our hypothesis that mini-KBI (M-KBI) with a shorter protrusion of side branch (SB) balloon would ascertain a better result after Culotte stenting. METHODS: Twenty-four coronary stents were deployed using Culotte approach in twelve bifurcation models with a bifurcation angle of 45°, 3.5 mm in MV diameter, and 3.0 mm in SB diameter. After stent implantation, the final KBI were assigned to C-KBI (two kissing balloons juxtaposed within the MV stent, at least overlap for 3 mm; n = 6) and M-KBI (the proximal marker of SB balloon just sited at the level of upper edge of SB ostium; n = 6). Proximal optimization technique (POT) was performed after KBI. Stent geometry was visually evaluated based on bench photos, microscopy, videoscopy, micro-CT, and scanning electron microscopy. Stent deformation index, minimal lumen diameter, and cross-sectional area at either carina level of MV and ostium of SB were measured from optical coherence tomography (OCT). RESULTS: In Culotte technique, C-KBI was associated with visually significant stent deformation, overexpansion and the "bottleneck" effect of the MV stent, which could not be effectively rectified by POT, while M-KBI could keep the circle shape of MV stent with good stent apposition in both MV and SB stent. By quantitative measurements, deformation index of MV was 0.06 ± 0.01 after M-KBI, significantly lower than 0.25 ± 0.02 if C-KBI was performed. In the line in carina, compared to C-KBI, M-KBI has smaller CSA-stent/CSA-reference, which indicated a less overstretch of MV stent. However, minimal lumen diameter and cross-sectional area of SB ostium was not different in the mini-KBI group (3.0958 ± 0.0285 mm and 7.9667 ± 0.1741 mm), when compared those after C-KBI (3.1217 ± 0.0772 mm and 7.9083 ± 0.3115 mm, p > .05). CONCLUSIONS: Followed by POT, M-KBI is preferable than C-KBI in preventing stent deformation, overexpansion in MV stent and could get well apposed of MV stent and well-opened SB stent as expected in a Culotte technique.

2.
Nat Genet ; 51(6): 1052-1059, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31152161

RESUMO

Maize is one of the most important crops globally, and it shows remarkable genetic diversity. Knowledge of this diversity could help in crop improvement; however, gold-standard genomes have been elucidated only for modern temperate varieties. Here, we present a high-quality reference genome (contig N50 of 15.78 megabases) of the maize small-kernel inbred line, which is derived from a tropical landrace. Using haplotype maps derived from B73, Mo17 and SK, we identified 80,614 polymorphic structural variants across 521 diverse lines. Approximately 22% of these variants could not be detected by traditional single-nucleotide-polymorphism-based approaches, and some of them could affect gene expression and trait performance. To illustrate the utility of the diverse SK line, we used it to perform map-based cloning of a major effect quantitative trait locus controlling kernel weight-a key trait selected during maize improvement. The underlying candidate gene ZmBARELY ANY MERISTEM1d provides a target for increasing crop yields.


Assuntos
Estudos de Associação Genética , Genoma de Planta , Genômica , Fenótipo , Zea mays/genética , Biologia Computacional/métodos , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Endogamia , Anotação de Sequência Molecular , Melhoramento Vegetal , Plantas Geneticamente Modificadas , Polimorfismo de Nucleotídeo Único , Característica Quantitativa Herdável
3.
Nat Commun ; 8(1): 1874, 2017 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-29187731

RESUMO

Maize was domesticated from lowland teosinte (Zea mays ssp. parviglumis), but the contribution of highland teosinte (Zea mays ssp. mexicana, hereafter mexicana) to modern maize is not clear. Here, two genomes for Mo17 (a modern maize inbred) and mexicana are assembled using a meta-assembly strategy after sequencing of 10 lines derived from a maize-teosinte cross. Comparative analyses reveal a high level of diversity between Mo17, B73, and mexicana, including three Mb-size structural rearrangements. The maize spontaneous mutation rate is estimated to be 2.17 × 10-8 ~3.87 × 10-8 per site per generation with a nonrandom distribution across the genome. A higher deleterious mutation rate is observed in the pericentromeric regions, and might be caused by differences in recombination frequency. Over 10% of the maize genome shows evidence of introgression from the mexicana genome, suggesting that mexicana contributed to maize adaptation and improvement. Our data offer a rich resource for constructing the pan-genome of Zea mays and genetic improvement of modern maize varieties.


Assuntos
Evolução Molecular , Genoma de Planta/genética , Zea mays/genética , Haplótipos
4.
Plant Biotechnol J ; 15(10): 1250-1263, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28218981

RESUMO

Amino acids are both constituents of proteins, providing the essential nutrition for humans and animals, and signalling molecules regulating the growth and development of plants. Most cultivars of maize are deficient in essential amino acids such as lysine and tryptophan. Here, we measured the levels of 17 different total amino acids, and created 48 derived traits in mature kernels from a maize diversity inbred collection and three recombinant inbred line (RIL) populations. By GWAS, 247 and 281 significant loci were identified in two different environments, 5.1 and 4.4 loci for each trait, explaining 7.44% and 7.90% phenotypic variation for each locus in average, respectively. By linkage mapping, 89, 150 and 165 QTLs were identified in B73/By804, Kui3/B77 and Zong3/Yu87-1 RIL populations, 2.0, 2.7 and 2.8 QTLs for each trait, explaining 13.6%, 16.4% and 21.4% phenotypic variation for each QTL in average, respectively. It implies that the genetic architecture of amino acids is relative simple and controlled by limited loci. About 43.2% of the loci identified by GWAS were verified by expression QTL, and 17 loci overlapped with mapped QTLs in the three RIL populations. GRMZM2G015534, GRMZM2G143008 and one QTL were further validated using molecular approaches. The amino acid biosynthetic and catabolic pathways were reconstructed on the basis of candidate genes proposed in this study. Our results provide insights into the genetic basis of amino acid biosynthesis in maize kernels and may facilitate marker-based breeding for quality protein maize.


Assuntos
Aminoácidos/metabolismo , Genes de Plantas , Zea mays/genética , Zea mays/metabolismo , Mapeamento Cromossômico , Estudo de Associação Genômica Ampla , Locos de Características Quantitativas
5.
J Integr Plant Biol ; 57(11): 943-53, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26282053

RESUMO

Genome information from model species such as rice can assist in the cloning of genes in a complex genome, such as maize. Here, we identified a maize ortholog of rice GS5 that contributes to kernel development in maize. The genome-wide association analysis of the expression levels of ZmGS5, and 15 of its 26 paralogs, identified a trans-regulator on chromosome 7, which was a BAK1-like gene. This gene that we named as ZmBAK1-7 could regulate the expression of ZmGS5 and three of the paralogs. Candidate-gene association analyses revealed that these five genes were associated with maize kernel development-related traits. Linkage analyses also detected that ZmGS5 and ZmBAK1-7 co-localized with mapped QTLs. A transgenic analysis of ZmGS5 in Arabidopsis thaliana L. showed a significant increase in seed weight and cell number, suggesting that ZmGS5 may have a conserved function among different plant species that affects seed development.


Assuntos
Frutas/crescimento & desenvolvimento , Oryza/genética , Proteínas de Plantas/genética , Zea mays/genética , Arabidopsis , Regulação da Expressão Gênica de Plantas , Oryza/crescimento & desenvolvimento , Plantas Geneticamente Modificadas , Zea mays/crescimento & desenvolvimento
6.
Heart Lung Circ ; 24(11): 1062-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26048317

RESUMO

BACKGROUND: To investigate the efficacy and safety of low-dose tirofiban in elderly patients undergoing primary percutaneous coronary intervention (PPCI) for acute myocardial infarction (AMI). METHODS: One hundred and four patients aged 70 years and above undergoing PPCI for AMI were divided into control (n=52) and study (n=52) groups. All patients received bolus intracoronary injection of tirofiban (10µg/kg), which was followed by intravenous infusion at 0.15µg/kg/min in the control group and at 0.075µg/kg/min in the study group for 24h. RESULTS: There was no statistically significant difference between the study group and the control group in patients with complete ST segment resolution (84.2% vs. 85.7%, P=0.851), peak high-sensitive cardiac troponin T level (5.1±1.9 vs. 5.8±2.6µg/L, P=0.123), scores of thrombus in the infarct-related artery (0.98±0.51 vs. 1.12±0.59, P=0.214), and patients with TIMI grade 3 flow (86.0% vs. 88.2%, P=0.737) after PPCI. There were no statistically significant differences between the two groups in left ventricular ejection fraction (57.1±6.3 vs. 57.7±6.1, P=0.611) and composite major adverse cardiovascular events rate (P =0.778) at 90 days after PCI. The total bleeding rate in the study group was lower than in the control group (P=0.048). CONCLUSION: In elderly patients with AMI undergoing primary PCI, low and standard dose of tirofiban exerts similar effects on platelet aggregation, coronary flow, infarct size, left ventricular systolic function and short-term clinical outcomes. Low dose regimen is associated with a lower bleeding rate than the standard dose.


Assuntos
Infarto do Miocárdio/sangue , Infarto do Miocárdio/terapia , Intervenção Coronária Percutânea , Troponina T/sangue , Tirosina/análogos & derivados , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Infarto do Miocárdio/fisiopatologia , Volume Sistólico/efeitos dos fármacos , Tirofibana , Tirosina/administração & dosagem
7.
Int J Cardiol ; 171(2): 161-8, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24380498

RESUMO

OBJECTIVES: Enhanced external counterpulsation (EECP) could improve endothelium-dependent vasodilatation of carotid artery and restore imbalance of nitric oxide and endothein-1 in patients with coronary artery disease. Our study was designed to test the hypothesis that long-term EECP may protect vascular endothelial cells from apoptosis by modifying apoptosis-related gene expression. METHODS: Eighteen male Yorkshire pigs were randomly assigned to three groups: usual diet (Normal), high cholesterol diet (HC) and high cholesterol diet plus EECP (HC+EECP). Vascular endothelial cells were isolated from the aortic endothelium and identified by CD31 staining and DiI-Ac-LDL reaction. Morphological changes were observed by both scanning and transmission electronic microscopes. TUNEL technique was applied to detect the apoptotic index of vascular endothelial cells. Two genes, Apaf-1 and BIRC2, were chosen for exploring the potential mechanisms of action at the molecular level. RESULTS: EECP brought a certain degree of alleviation from ultrastructural changes such as shrinking and blebbing of cytomembrane, marginalization, degeneration, and fragmentation of the nucleus. EECP also significantly reduced apoptotic indices while compared with that of control (177±12‰ vs. 237±23‰, P<0.05). The Apaf-1 expression at both protein and mRNA level in pigs of HC+EECP group was significantly decreased than those of the HC group (P<0.05), whereas the BIRC2 expression was significantly enhanced after EECP treatment, documented by immunostaining and semi-quantitative RT-PCR analysis, respectively (P<0.05). CONCLUSIONS: EECP could protect vascular endothelial cells from apoptosis, thereby delaying the progression of early atherosclerotic lesions possibly through transcriptional down-regulation of pro-apoptotic gene Apaf-1, and up-regulation of anti-apoptotic gene BIRC2.


Assuntos
Apoptose/genética , Fator Apoptótico 1 Ativador de Proteases/genética , Contrapulsação/métodos , Células Endoteliais/patologia , Hipercolesterolemia , Proteínas Inibidoras de Apoptose/genética , Animais , Aorta Abdominal/patologia , Aorta Abdominal/fisiologia , Artérias Carótidas/patologia , Artérias Carótidas/fisiologia , Modelos Animais de Doenças , Células Endoteliais/fisiologia , Regulação da Expressão Gênica/fisiologia , Hipercolesterolemia/genética , Hipercolesterolemia/patologia , Hipercolesterolemia/terapia , Masculino , Distribuição Aleatória , Sus scrofa , Ubiquitina-Proteína Ligases , Vasodilatação/fisiologia
8.
Heart Vessels ; 25(2): 97-103, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20339970

RESUMO

This study was designed to investigate the effect of low-dose nesiritide on renal function and major cardiac events in patients with acute decompensated heart failure following acute myocardial infarction. Sixty patients were randomized into nesiritide (loading dose 0.5 microg/kg, maintenance dose 0.0075 microg/kg/min) and nitroprusside groups. Compared with the nitroprusside group, the nesiritide group had a greater heart rate reduction (P < 0.05), higher 24 h urine volume (P < 0.001), and more significant alleviation in dyspnea (P < 0.001). The prevalence of hypotension in the nesiritide group was lower than in the nitroprusside group (7.4% vs 28.5%, P < 0.05). The nesiritide group had a greater reduction in serum noradrenaline, angiotensin II, aldosterone, endothelin, and N-terminal prohormone brain natriuretic peptide (all P < 0.01). The mean serum creatinine in the nesiritide group was reduced (109.4 +/- 26.6 vs 102.8 +/- 21.6 micromol/l, P < 0.01), whereas it remained unchanged in the nitroprusside group (106.8 +/- 20 vs 106.0 +/- 19.2 micromol/l, P > 0.05). The rehospitalization or mortality rate was similar between the two groups 3 months after the therapy (P > 0.05). We conclude that low-dose nesiritide is more effective in suppressing the activation of the sympathetic and renin-angiotensin systems. It also improves the clinical symptoms and enhances renal function, but its effect on hospital readmission or mortality rate needs further investigation.


Assuntos
Fármacos Cardiovasculares/administração & dosagem , Insuficiência Cardíaca/tratamento farmacológico , Nefropatias/tratamento farmacológico , Rim/efeitos dos fármacos , Infarto do Miocárdio/tratamento farmacológico , Peptídeo Natriurético Encefálico/administração & dosagem , Nitroprussiato/administração & dosagem , Idoso , Biomarcadores/sangue , Fármacos Cardiovasculares/efeitos adversos , Distribuição de Qui-Quadrado , Creatinina/sangue , Feminino , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/fisiopatologia , Hemodinâmica/efeitos dos fármacos , Humanos , Rim/fisiopatologia , Nefropatias/etiologia , Nefropatias/mortalidade , Nefropatias/fisiopatologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/fisiopatologia , Peptídeo Natriurético Encefálico/efeitos adversos , Peptídeo Natriurético Encefálico/sangue , Nitroprussiato/efeitos adversos , Readmissão do Paciente , Fragmentos de Peptídeos/sangue , Volume Sistólico/efeitos dos fármacos , Fatores de Tempo , Resultado do Tratamento , Função Ventricular Esquerda/efeitos dos fármacos
9.
Chin Med J (Engl) ; 122(10): 1188-94, 2009 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-19493469

RESUMO

BACKGROUND: Enhanced external counterpulsation (EECP) improves ischemia in patients with refractory angina pectoris, but the mechanism remains unclear. To explore the mechanisms of EECP action, we detected progenitor cells presenting any of the following markers CD34(+), CD29(+), and CD106(+). METHODS: Growth cytokines-mediated progenitor cell mobilization and associated angiogenesis potential were assessed in a porcine model of hypercholesterolemia. Twenty-four male domestic swines were randomly assigned to 4 groups: normal diet (control, n = 6), hypercholesterolemic diet (CHOL, n = 6), hypercholesterolemic diet with administration of recombinant human granulocyte colony-stimulating factor (rhG-CSF) (rhG-CSF, n = 6), and hypercholesterolemic diet with EECP treatment (EECP, n = 6). EECP was applied 2 hours every other day for a total of 36 hours. Serum levels of vascular endothelial growth factor (VEGF) and granulocyte colony-stimulating factor (G-CSF), peripheral blood progenitor cell counts, level of regional angiogenesis, and expression of VEGF and stromal cell derived factor 1alpha (SDF-1alpha) in porcine myocardium were assessed, respectively. RESULTS: A porcine model of hypercholesterolemia-induced arteriosclerosis was successfully established. There was no significant difference in serum levels of VEGF among the four groups. The serum levels of G-CSF in the EECP group increased significantly at week 15 and week 18 ((38.3 +/- 5.6) pg/ml at week 15 vs (26.2 +/- 3.7) pg/ml at week 12, P < 0.05, and (46.9 +/- 6.1) pg/ml at week 18 vs (26.2 +/- 3.7) pg/ml at week 12, P < 0.01). The serum levels of G-CSF in group 3 increased also significantly after receiving rhG-CSF injection for five days ((150 +/- 13.9) pg/ml at week 18 vs (24.8 +/- 5.4) pg/ml at week 12, P < 0.01). Compared to other groups and other time points, progenitor cell counts increased significantly after 2-hour EECP treatment (108 +/- 13 vs 26 +/- 6 per 10(5) leukocytes, P < 0.01), but not at week 18. The progenitor cell counts also increased significantly after subcutaneous injection of rhG-CSF for five days compared to the week 12 (baseline) (180 +/- 21 vs 25 +/- 7 per 10(5) leukocytes, P < 0.01). There was no significant difference among the four groups at other time points. Moreover, the expression of VEGF and SDF-1alpha and the level of regional angiogenesis in myocardium increased significantly in both EECP and rhG-CSF groups. CONCLUSIONS: The results demonstrated that EECP could facilitate angiogenesis in the myocardium of atherosclerotic swines by increasing endogenous G-CSF, inducing an enhanced mobilization of progenitor cells and augmenting myocardial expression of VEGF and SDF-1alpha.


Assuntos
Arteriosclerose/fisiopatologia , Contrapulsação/métodos , Hipercolesterolemia/cirurgia , Miocárdio/metabolismo , Neovascularização Patológica/metabolismo , Neovascularização Patológica/cirurgia , Animais , Western Blotting , Quimiocina CXCL12/metabolismo , Modelos Animais de Doenças , Eletroforese em Gel de Poliacrilamida , Fator Estimulador de Colônias de Granulócitos/sangue , Fator Estimulador de Colônias de Granulócitos/metabolismo , Humanos , Hipercolesterolemia/metabolismo , Imuno-Histoquímica , Masculino , Distribuição Aleatória , Proteínas Recombinantes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células-Tronco/citologia , Suínos , Fator A de Crescimento do Endotélio Vascular/sangue , Fator A de Crescimento do Endotélio Vascular/metabolismo
10.
Zhongguo Wei Zhong Bing Ji Jiu Yi Xue ; 20(11): 663-6, 2008 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-19000422

RESUMO

OBJECTIVE: To explore the effect of long-term enhanced external counterpulsation (EECP) on morphological damage of endomembrane and endothelium-dependent vasodilatation of the carotid arteries of hypercholesterolemic pigs. METHODS: Eighteen male infant pigs were randomly divided into three groups according to the contents of their diet: the normal control group (n=6), the high-cholesterol feeding control group (n=6) and EECP group (n=6). Porcine model of hypercholesterolemia was reproduced by feeding animals with high-cholesterol diet. After completion of EECP treatment for 36 hours in EECP group, carotid arterial rings were harvested from all animals. Both scanning and transmission electron microscopy was employed to observe the changes in morphology of their endomembrane. At the same time, their vasodilatation response to variant dose of acetylcholine (Ach) was detected. RESULTS: The surface of endothelium in the normal control group was smooth, and endothelial cells were in regular streamline array, and they were almost in same size, attaching closely to matrix without smooth muscle cell proliferation and lipid infiltration in intima. In contrast, the endothelial cells of hypercholesterolemic pigs were in irregular array, with marked desquamation, resulting in loose linkage. Smooth muscle cells were found to invade into intimal layer and proliferated, and foam cells could also be found in intimal layer. In hypercholesterolemic pigs treated with EECP, slight intimal damage was found. In addition, with Ach dose of 10(-8) mol/L to 10(-5)mol/L, endothelium-dependent vasodilatation ratio in hypercholesterolemic pigs with or without EECP treatment, was significantly lower than that of the normal control group (all P<0.05). However, endothelium-dependent vasodilatation ratio in pigs with EECP treatment was obviously higher compared with hypercholesterolemic pigs without EECP treatment with the dosage of Ach concentration ranged from 10(-7) mol/L to 10(-5) mol/L (all P<0.05). CONCLUSION: Long-term EECP ameliorates both the morphological damage and the impaired endothelium-dependent vasodilatation function resulting from hypercholesterolemia, contributing to prevention of atherosclerosis.


Assuntos
Artérias Carótidas/patologia , Contrapulsação , Hipercolesterolemia/patologia , Túnica Íntima/patologia , Animais , Artérias Carótidas/fisiopatologia , Modelos Animais de Doenças , Hipercolesterolemia/fisiopatologia , Técnicas In Vitro , Masculino , Suínos , Túnica Íntima/fisiopatologia , Vasodilatação/fisiologia
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