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1.
Plant Cell ; 32(10): 3095-3112, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32732312

RESUMEN

Petals can be simple or elaborate, depending on whether they have lobes, teeth, fringes, or appendages along their margins, or possess spurs, scales, or other types of modifications on their adaxial/abaxial side, or both. Elaborate petals have been recorded in 23 orders of angiosperms and are generally believed to have played key roles in the adaptive evolution of corresponding lineages. The mechanisms underlying the formation of elaborate petals, however, are largely unclear. Here, by performing extensive transcriptomic and functional studies on Nigella damascena (Ranunculaceae), we explore the mechanisms underlying elaborate petal development and specialized character formation. In addition to the identification of genes and programs that are specifically/preferentially expressed in petals, we found genes and programs that are required for elaborate rather than simple petal development. By correlating the changes in gene expression with those in petal development, we identified 30 genes that are responsible for the marginal/ventral elaboration of petals and the initiation of several highly specialized morphological characters (e.g., pseudonectaries, long hairs, and short trichomes). Expression and functional analyses further confirmed that a class I homeodomain-leucine zipper family transcription factor gene, Nigella damascena LATE MERISTEM IDENTITY1 (NidaLMI1), plays important roles in the development of short trichomes and bifurcation of the lower lip. Our results not only provide the first portrait of elaborate petal development but also pave the way to understanding the mechanisms underlying lateral organ diversification in plants.


Asunto(s)
Flores/crecimiento & desarrollo , Genes de Plantas , Genes Reguladores , Ranunculaceae/crecimiento & desarrollo , Ranunculaceae/genética , Flores/genética , Regulación de la Expresión Génica de las Plantas
2.
Connect Tissue Res ; 59(1): 55-65, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28267379

RESUMEN

Purpose/Aim of the study: To evaluate the biomechanical characteristics and biocompatibility of an injectable, biodegradable calcium phosphate cement (CPC) containing poly lactic-co-glycolic acid (PLGA). MATERIALS AND METHODS: A vertebral compression fracture model was established using 20 human cadaveric vertebrae (T11-L3) divided into CPC/PLGA composite versus PMMA groups for biomechanical testing. In addition, 35 New Zealand rabbits were used to evaluate biodegradability and osteoconductive properties of CPC/PLGA using a bone defect model. In vitro cytotoxicity was evaluated by culturing with L929 cells. RESULTS: The CPC/PLGA composite effectively restored vertebral biomechanical properties. Compared with controls, the maximum load and compression strength of the CPC/PLGA group were lower, and stiffness was lower after kyphoplasty (all p <.05). Degradation was much slower in the control CPC compared with CPC/PLGA group. The bone tissue percentage in the CPC/PLGA group (44.9 ± 23.7%) was significantly higher compared with control CPC group (25.7 ± 10.9%) (p <.05). The viability of cells cultured on CPC/PLGA was greater than 70% compared with the blanks. CONCLUSIONS: Our biodegradable CPC/PLGA composite showed good biomechanical properties, cytocompatibility, and osteoconductivity and may represent an ideal bone substitute for future applications.


Asunto(s)
Cementos para Huesos , Fosfatos de Calcio , Fracturas por Compresión/terapia , Ensayo de Materiales , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Fracturas de la Columna Vertebral/terapia , Animales , Cementos para Huesos/química , Cementos para Huesos/farmacología , Fosfatos de Calcio/química , Fosfatos de Calcio/farmacología , Línea Celular , Modelos Animales de Enfermedad , Femenino , Fracturas por Compresión/metabolismo , Fracturas por Compresión/patología , Humanos , Masculino , Ratones , Persona de Mediana Edad , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/farmacología , Conejos , Fracturas de la Columna Vertebral/metabolismo , Fracturas de la Columna Vertebral/patología
3.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 33(5): 649-52, 2016 Oct.
Artículo en Zh | MEDLINE | ID: mdl-27577214

RESUMEN

OBJECTIVE: To analyze mutation of the PMP22 gene in a pedigree affected with Charcot-Marie-Tooth disease. METHODS: Genomic DNA was extracted from peripheral blood samples of the proband and members from his family, and fetal DNA was extracted from amniotic fluid sample. Multiplex ligation-dependent probe amplification (MLPA) and array-based comparative genomic hybridization (array-CGH) analyses were carried out to determine the copy number of the PMP22 gene. Sanger sequencing was carried out to detect point mutations of the PMP22 gene. RESULTS: A heterozygous duplication of the PMP22 gene was detected in the proband and his father, while no point mutation, insertion or deletion was found in them. No duplication or deletion of the PMP22 gene was found in other family members. CONCLUSION: Based on clinical symptoms and genetic findings, the heterozygous duplication of the PMP22 gene is probably the cause of the disease in the proband. The fact that the father has carried the same duplication but with no detectable symptom may be due to irregular transmission pattern of the mutation. Genetic counseling for the family should therefore be with caution.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth/genética , Duplicación de Gen , Predisposición Genética a la Enfermedad/genética , Proteínas de la Mielina/genética , Adulto , Hibridación Genómica Comparativa/métodos , Análisis Mutacional de ADN , Salud de la Familia , Femenino , Dosificación de Gen , Heterocigoto , Humanos , Masculino , Reacción en Cadena de la Polimerasa Multiplex/métodos , Linaje
4.
Mol Cell Biochem ; 395(1-2): 265-72, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24997628

RESUMEN

The growth and metastasis of solid tumors depends on angiogenesis. Anti-angiogenesis therapy may represent a promising therapeutic option. Vasostatin, the N-terminal domain of calreticulin, is a very potent endogenous inhibitor of angiogenesis and tumor growth. In this study, we attempted to investigate whether plasmid-encoding vasostatin complexed with cationic liposome could suppress the growth and metastasis of hepatocellular carcinoma in vivo and discover its possible mechanism of action. Apoptosis induction of pSecTag2B-vasostatin plasmid on murine endothelial cells (MS1) was examined by flow cytometric analysis in vitro. Nude mice bearing HCCLM3 tumor received pSecTag2B-vasostatin, pSecTag2B-Null, and 0.9 % NaCl solution, respectively. Tumor net weight was measured and survival time was observed. Microvessel density within tumor tissues was determined by CD31 immunohistochemistry. H&E staining of lungs and TUNEL assay of primary tumor tissues were also conducted. The results displayed that pSecTag2B-vasostatin could inhibit the growth and metastasis of hepatocellular carcinoma xenografts and prolong survival time compared with the controls in vivo. Moreover, histologic analysis revealed that pSecTag2B-vasostatin treatment increased apoptosis and inhibited angiogenesis. The present data may be of importance to the further exploration of this new anti-angiogenesis approach in the treatment of hepatocellular cancer.


Asunto(s)
Calreticulina/genética , Carcinoma Hepatocelular/terapia , Liposomas/administración & dosificación , Neoplasias Hepáticas/terapia , Fragmentos de Péptidos/genética , Animales , Calreticulina/metabolismo , Calreticulina/farmacología , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Femenino , Terapia Genética , Vectores Genéticos/administración & dosificación , Humanos , Neoplasias Hepáticas/patología , Ratones , Metástasis de la Neoplasia , Neoplasias Experimentales , Fragmentos de Péptidos/metabolismo , Fragmentos de Péptidos/farmacología , Plásmidos/genética
5.
Pharm Res ; 31(10): 2857-67, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25208873

RESUMEN

PURPOSE: The purpose of this study was to develop and evaluate the azithromycin cationic non-lecithoid nano/microparticles with high bioavailability and lung targeting efficiency. METHODS: The cationic niosomes with different sizes (AMCNS-S and AMCNS-L) along with varied built-in characteristics were produced to achieve high bioavailability and lung targeting efficiency of azithromycin (AM) via two administration routes widely used in clinical practice, i.e., oral and intravenous routes, instead of transdermal route (by which the only marketed niosome-based drug delivery dermatologic products were given). The possible explanations for improved bioavailability and lung targeting efficacy were put forward here. RESULTS: AMCNS-S (or AMCNS-L) had high bioavailability, for example, the oral (or intravenous) relative bioavailability of AMCNS-S (or AMCNS-L) to free AM increased to 273.19% (or 163.50%). After intravenous administration, AMCNS-S (or AMCNS-L) had obvious lung targeting efficiency, for example, the lung AM concentration of AMCNS-S (or AMCNS-L) increased 16 (or 28) times that of free AM at 12 h; the AM concentration of AMCNS-S (or AMCNS-L) in lung was higher than that in heart and kidney all the time. CONCLUSIONS: The development of niosome-based AM nanocarriers provides valuable tactics in antibacterial therapy and in non-lecithoid niosomal application.


Asunto(s)
Antibacterianos/administración & dosificación , Azitromicina/administración & dosificación , Portadores de Fármacos/química , Pulmón/metabolismo , Nanopartículas/química , Administración Oral , Animales , Antibacterianos/farmacocinética , Azitromicina/farmacocinética , Disponibilidad Biológica , Cationes , Absorción Gástrica , Inyecciones Intravenosas , Absorción Intestinal , Liposomas , Pulmón/efectos de los fármacos , Masculino , Tamaño de la Partícula , Ratas Sprague-Dawley , Propiedades de Superficie
6.
Bioresour Technol ; 395: 130352, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38272142

RESUMEN

The productive separation and conversion of corn straw offers significant prospects for the economic viability of biorefineries centered on straw resources. In this work, a graded utilization method was proposed to produce xylo-oligosaccharides (XOS), ethanol and lignin from corn straw by nicotinic acid (NA) hydrolysis and water/pentanol pretreatment. A XOS yield of 52.6 % was achieved under optimized conditions of 100 mM NA, 170 °C and 30 min. The solid residue was directly treated with water/pentanol, achieving a lignin removal rate of 79.7 %, and the total XOS yield was improved to 62.6 %. The lignin recovered from pentanol had a high purity of 97.6 %, with high phenolic OH content. Simultaneous saccharification and fermentation of final residue resulted in an ethanol yield of 92.0 %, which yielded 55.3 g/L ethanol. Thus, NA hydrolysis and water/pentanol pretreatment provided an efficient, environmentally friendly approach to fractionate corn straw for the co-production of XOS, ethanol, and lignin.


Asunto(s)
Glucuronatos , Lignina , Niacina , Lignina/química , Zea mays , Etanol , Pentanoles , Hidrólisis , Oligosacáridos , Fermentación , Agua
7.
Drug Dev Ind Pharm ; 39(9): 1364-71, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22994163

RESUMEN

The purpose of this study was to evaluate the taste masking potential of novel solid dispersions (SDs) using Eudragit® EPO as the excipient when incorporated into the orally disintegrating tablets (ODTs) for delivering a highly soluble drug with an extremely bitter taste. The pyridostigmine bromides (PB) SDs (PBSDs) were prepared by solvent evaporation-deposition method. The physicochemical properties of PBSDs were investigated by means of differential scanning calorimetry and Fourier transformed infrared spectroscopy. The dissolution test showed that only about 8% of PB was released from PBSDs in the simulated salivary fluid in 30 s. Therefore, PBSDs were considered taste-masked and selected for formulation of PBODTs. A central composite design was employed for process optimization. Multiple linear regression analysis for process optimization revealed that the optimal PBODTs were obtained, when the microcrystalline cellulose and crospovidone were 17.16 and 5.55 (%, w/w), respectively, and the average in vivo disintegration time was 25 s. The bitterness threshold of PB was examined by a sensory test, and the threshold value was set as 3 mg in each tablet. Taste evaluation of PBODTs in 18 volunteers revealed considerable taste masking with bitterness below the threshold value. PBODTs also revealed rapid drug release (around 99%, 2 min) in the simulated gastric fluid. The mean PB plasma concentration-time profiles of PBODTs and that of the commercial tablets were comparable, with closely similar pattern. Bioequivalence assessment results demonstrated that PBODTs and the commercial tablets were bioequivalent. In conclusion, PBODTs are prepared successfully, with taste masking and rapid disintegration in the oral cavity.


Asunto(s)
Inhibidores de la Colinesterasa/química , Aromatizantes/química , Modelos Químicos , Bromuro de Piridostigmina/química , Animales , Celulosa/química , Fenómenos Químicos , Química Farmacéutica/métodos , Inhibidores de la Colinesterasa/efectos adversos , Inhibidores de la Colinesterasa/análisis , Inhibidores de la Colinesterasa/farmacocinética , Excipientes/química , Femenino , Aromatizantes/metabolismo , Humanos , Cinética , Masculino , Ácidos Polimetacrílicos/química , Povidona/química , Bromuro de Piridostigmina/efectos adversos , Bromuro de Piridostigmina/análisis , Bromuro de Piridostigmina/farmacocinética , Conejos , Distribución Aleatoria , Saliva/química , Solubilidad , Comprimidos , Gusto , Equivalencia Terapéutica
8.
Huan Jing Ke Xue ; 44(8): 4507-4518, 2023 Aug 08.
Artículo en Zh | MEDLINE | ID: mdl-37694645

RESUMEN

Microplastics are widely distributed in the soil environment, threatening the soil ecological environment system and changing soil physicochemical properties and microbial characteristics. Biochar is often used as a soil amendment to improve soil quality due to its special pore structure and good soil nutrient retention ability. However, the understanding of the effects and mechanisms of biochar application on the physicochemical properties and bacterial communities of microplastic-contaminated soils is still very limited. Therefore, a 21-day micro-soil culture experiment was conducted to analyze the effects of biochar application on physicochemical properties and bacterial community changes in soil contaminated with different concentrations of microplastics using 16S rRNA high-throughput sequencing technology. The results revealed that the application of biochar slowed down the decrease in nitrate nitrogen and Olsen-P contents in microplastic-contaminated soil and increased the total phosphorus content. Biochar addition increased the relative abundance of tolerant phylum such as Acidobacteriota, Actinobacteriota, and Bacteroidota in microplastic-contaminated calcareous soil. Proteobacteria, Acidobacteriota, and Actinobacteriota were the dominant bacteria of the soil bacterial community in each treatment on day 7 and day 21. Compared with that on day 7, the relative abundance of Proteobacteria and Firmicutes significantly decreased, and the relative abundance of Acidobacteriota, Actinobacteriota, Bacteroidota, Chloroflexi, and Myxococcota increased on day 21. Biochar application also increased the relative abundance of Lysobacter in microplastic-contaminated soils. This study demonstrated that the application of biochar increased microplastic-resistant bacteria, enhanced the stability of microplastic-contaminated soil, and slowed down the pollution of microplastics to the soil. Moreover, biochar had great potential to improve the quality of microplastic-contaminated calcareous soil.


Asunto(s)
Microplásticos , Plásticos , ARN Ribosómico 16S/genética , Bacterias/genética , Acidobacteria , Bacteroidetes , Proteobacteria , Suelo
9.
Shanghai Kou Qiang Yi Xue ; 23(4): 427-30, 2014 Aug.
Artículo en Zh | MEDLINE | ID: mdl-25338792

RESUMEN

PURPOSE: To evaluate the effect of impressions made by agar/alginate compared with silicon rubber material. METHODS: Five moulds of bi-root canal molar, with different root canal angles of 0°, 10°, 20°, 30° and 40° were made. Twenty impressions were made for each mould with either silicon rubber or agar/alginate. The effects of two methods were evaluated and the influence of angles between root canals on the impression methods was analyzed. The data was analyzed with SPSS16.0 software package. RESULTS: Significant difference of integrality rate (IR) of impression was not found in silicon rubber group among different angle groups (P>0.05). IR of 40° group (60%) was significantly lower than that of 0°(95%) and general IR (83%) when using agar (P<0.05). IR of agar (60%) was statistically lower than silicon rubber (90%) in 40° group (P<0.05).The success rate of agar method was significantly lower than silicon rubber method in 40° group. The general IR of agar (83%) was significantly lower than that of silicon rubber (95%) (P<0.05). A significant negative correlation was observed between root canal angles and IR (r=-0.901,P=0.037). CONCLUSIONS: Silicon rubber impression materials are suggested for impression taking when root canal angles are over 30° in molars, while agar/alginate impression method is qualified for smaller angles. The general IR of silicon rubber material is better than that of agar when taking the impression of post and core in molar.


Asunto(s)
Agar , Cavidad Pulpar , Alginatos , Técnica de Impresión Dental , Ácido Glucurónico , Ácidos Hexurónicos , Humanos , Diente Molar , Tratamiento del Conducto Radicular
10.
Bing Du Xue Bao ; 29(2): 132-6, 2013 Mar.
Artículo en Zh | MEDLINE | ID: mdl-23757842

RESUMEN

To analyze the genomic sequence characteristics of a human Echovirus 9(ECHO-9) strain isolated from a child with Hand-foot-mouth disease (HFMD) in Kunming, Yunnan Province, in 2010. The complete genome sequence of a human echovirus 9 strain, MSH-KM812-2010 was determined. As other human enterovirus, its genome was 7,424 nucleotides (nts) in length and encoded for 2,203 amino acids (aas). In comparison to other human enteroviruses, MSH-KM812-2010 strain had the highest homology with other strains of human echovirus 9 in structural genomic regions and more homologous to other serotypes of B specie than to human echovirus 9 in non-structural genomic regions. Phylogenetic analysis based on complete VP1 gene revealed that the sequences of human echovirus 9 segregated into three distinct clades A, B and C with more than 15. 0% diversity between clades. All Chinese isolates belonged to the same clade. RDP3 and Blast revealed evident recombination in non-structural genomic regions. This report is the first to, describe the complete genome of the human echovirus 9 in China and provide an overview of the diversity of genetic characteristics of a circulating human echovirus 9.


Asunto(s)
Echovirus 9/genética , Echovirus 9/aislamiento & purificación , Genoma Viral , Secuencia de Bases , China , Echovirus 9/clasificación , Femenino , Humanos , Lactante , Datos de Secuencia Molecular , Filogenia , Proteínas Virales/genética
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