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1.
Braz. j. biol ; 842024.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469387

RESUMEN

Abstract Germin-like proteins (GLPs) play an important role against various stresses. Vitis vinifera L. genome contains 7 GLPs; many of them are functionally unexplored. However, the computational analysis may provide important new insight into their function. Currently, physicochemical properties, subcellular localization, domain architectures, 3D structures, N-glycosylation & phosphorylation sites, and phylogeney of the VvGLPs were investigated using the latest computational tools. Their functions were predicted using the Search tool for the retrieval of interacting genes/proteins (STRING) and Blast2Go servers. Most of the VvGLPs were extracellular (43%) in nature but also showed periplasmic (29%), plasma membrane (14%), and mitochondrial- or chloroplast-specific (14%) expression. The functional analysis predicted unique enzymatic activities for these proteins including terpene synthase, isoprenoid synthase, lipoxygenase, phosphate permease, receptor kinase, and hydrolases generally mediated by Mn+ cation. VvGLPs showed similarity in the overall structure, shape, and position of the cupin domain. Functionally, VvGLPs control and regulate the production of secondary metabolites to cope with various stresses. Phylogenetically VvGLP1, -3, -4, -5, and VvGLP7 showed greater similarity due to duplication while VvGLP2 and VvGLP6 revealed a distant relationship. Promoter analysis revealed the presence of diverse cis-regulatory elements among which CAAT box, MYB, MYC, unnamed-4 were common to all of them. The analysis will help to utilize VvGLPs and their promoters in future food programs by developing resistant cultivars against various biotic (Erysiphe necator and in Powdery Mildew etc.) and abiotic (Salt, drought, heat, dehydration, etc.) stresses.


Resumo As proteínas do tipo germin (GLPs) desempenham um papel importante contra vários estresses. O genoma de Vitis vinifera L. contém 7 GLPs; muitos deles são funcionalmente inexplorados. No entanto, a análise computacional pode fornecer informações importantes sobre sua função. Atualmente, as propriedades físico-químicas, localização subcelular, arquitetura de domínio, estruturas 3D, sítios de N-glicosilação e fosforilação e estudos filogenéticos dos VvGLPs foram conduzidos usando as ferramentas computacionais mais recentes. Suas funções foram previstas usando a ferramenta Search para recuperação de genes/proteínas em interação (STRING) e servidores Blast2Go. A maioria dos VvGLPs são extracelulares (43%) na natureza, mas também mostraram expressão periplasmática (29%), na membrana plasmática (14%) e específica para mitocôndrias ou cloroplastos (14%). A análise funcional previu atividades enzimáticas únicas para essas proteínas, incluindo terpeno sintase, isoprenoide sintase, lipoxigenase, fosfato permease, receptor quinase e hidrolases geralmente mediadas por cátion Mn +. VvGLPs mostraram similaridade na estrutura geral, forma e posição do domínio cupin. Funcionalmente, os VvGLPs controlam e regulam a produção de metabólitos secundários para lidar com vários estresses. Filogeneticamente, VvGLP1, -3, -4, -5 e VvGLP7 mostraram maior similaridade devido à duplicação, enquanto VvGLP2 e VvGLP6 revelaram uma relação distante. A análise do promotor revelou a presença de diversos elementos cis-reguladores, entre os quais CAAT box, MYB, MYC, sem nome-4, sendo comum a todos eles. A análise ajudará a utilizar VvGLPs e seus promotores em programas alimentares futuros, desenvolvendo cultivares resistentes contra vários estresses bióticos (Erysiphe necator e no oídio, etc.) e abióticos (sal, seca, calor, estresse hídrico, etc.).

2.
Braz. j. biol ; 84: e256732, 2024. tab, graf, ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1364524

RESUMEN

Germin-like proteins (GLPs) play an important role against various stresses. Vitis vinifera L. genome contains 7 GLPs; many of them are functionally unexplored. However, the computational analysis may provide important new insight into their function. Currently, physicochemical properties, subcellular localization, domain architectures, 3D structures, N-glycosylation & phosphorylation sites, and phylogeney of the VvGLPs were investigated using the latest computational tools. Their functions were predicted using the Search tool for the retrieval of interacting genes/proteins (STRING) and Blast2Go servers. Most of the VvGLPs were extracellular (43%) in nature but also showed periplasmic (29%), plasma membrane (14%), and mitochondrial- or chloroplast-specific (14%) expression. The functional analysis predicted unique enzymatic activities for these proteins including terpene synthase, isoprenoid synthase, lipoxygenase, phosphate permease, receptor kinase, and hydrolases generally mediated by Mn+ cation. VvGLPs showed similarity in the overall structure, shape, and position of the cupin domain. Functionally, VvGLPs control and regulate the production of secondary metabolites to cope with various stresses. Phylogenetically VvGLP1, -3, -4, -5, and VvGLP7 showed greater similarity due to duplication while VvGLP2 and VvGLP6 revealed a distant relationship. Promoter analysis revealed the presence of diverse cis-regulatory elements among which CAAT box, MYB, MYC, unnamed-4 were common to all of them. The analysis will help to utilize VvGLPs and their promoters in future food programs by developing resistant cultivars against various biotic (Erysiphe necator and in Powdery Mildew etc.) and abiotic (Salt, drought, heat, dehydration, etc.) stresses.


As proteínas do tipo germin (GLPs) desempenham um papel importante contra vários estresses. O genoma de Vitis vinifera L. contém 7 GLPs; muitos deles são funcionalmente inexplorados. No entanto, a análise computacional pode fornecer informações importantes sobre sua função. Atualmente, as propriedades físico-químicas, localização subcelular, arquitetura de domínio, estruturas 3D, sítios de N-glicosilação e fosforilação e estudos filogenéticos dos VvGLPs foram conduzidos usando as ferramentas computacionais mais recentes. Suas funções foram previstas usando a ferramenta Search para recuperação de genes/proteínas em interação (STRING) e servidores Blast2Go. A maioria dos VvGLPs são extracelulares (43%) na natureza, mas também mostraram expressão periplasmática (29%), na membrana plasmática (14%) e específica para mitocôndrias ou cloroplastos (14%). A análise funcional previu atividades enzimáticas únicas para essas proteínas, incluindo terpeno sintase, isoprenoide sintase, lipoxigenase, fosfato permease, receptor quinase e hidrolases geralmente mediadas por cátion Mn +. VvGLPs mostraram similaridade na estrutura geral, forma e posição do domínio cupin. Funcionalmente, os VvGLPs controlam e regulam a produção de metabólitos secundários para lidar com vários estresses. Filogeneticamente, VvGLP1, -3, -4, -5 e VvGLP7 mostraram maior similaridade devido à duplicação, enquanto VvGLP2 e VvGLP6 revelaram uma relação distante. A análise do promotor revelou a presença de diversos elementos cis-reguladores, entre os quais CAAT box, MYB, MYC, sem nome-4, sendo comum a todos eles. A análise ajudará a utilizar VvGLPs e seus promotores em programas alimentares futuros, desenvolvendo cultivares resistentes contra vários estresses bióticos (Erysiphe necator e no oídio, etc.) e abióticos (sal, seca, calor, estresse hídrico, etc.).


Asunto(s)
Estrés Fisiológico/genética , Proteínas , Vitis/genética
3.
Braz J Biol ; 84: e256732, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35293478

RESUMEN

Germin-like proteins (GLPs) play an important role against various stresses. Vitis vinifera L. genome contains 7 GLPs; many of them are functionally unexplored. However, the computational analysis may provide important new insight into their function. Currently, physicochemical properties, subcellular localization, domain architectures, 3D structures, N-glycosylation & phosphorylation sites, and phylogeney of the VvGLPs were investigated using the latest computational tools. Their functions were predicted using the Search tool for the retrieval of interacting genes/proteins (STRING) and Blast2Go servers. Most of the VvGLPs were extracellular (43%) in nature but also showed periplasmic (29%), plasma membrane (14%), and mitochondrial- or chloroplast-specific (14%) expression. The functional analysis predicted unique enzymatic activities for these proteins including terpene synthase, isoprenoid synthase, lipoxygenase, phosphate permease, receptor kinase, and hydrolases generally mediated by Mn+ cation. VvGLPs showed similarity in the overall structure, shape, and position of the cupin domain. Functionally, VvGLPs control and regulate the production of secondary metabolites to cope with various stresses. Phylogenetically VvGLP1, -3, -4, -5, and VvGLP7 showed greater similarity due to duplication while VvGLP2 and VvGLP6 revealed a distant relationship. Promoter analysis revealed the presence of diverse cis-regulatory elements among which CAAT box, MYB, MYC, unnamed-4 were common to all of them. The analysis will help to utilize VvGLPs and their promoters in future food programs by developing resistant cultivars against various biotic (Erysiphe necator and in Powdery Mildew etc.) and abiotic (Salt, drought, heat, dehydration, etc.) stresses.


Asunto(s)
Vitis , Glicoproteínas/genética , Glicoproteínas/metabolismo , Proteínas de Plantas/metabolismo , Vitis/genética
5.
J Appl Microbiol ; 117(4): 1079-94, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24995828

RESUMEN

AIMS: To describe microbial diversity, biofilm composition and biogeochemical potential within biofilms in the water overlying uranium tailings characterized by high pH, high metal concentration and low permeability. METHODS AND RESULTS: To estimate microbial diversity in biofilms formed in water columns overlying uranium mine tailings, culture-dependent and culture-independent methods were employed. High-throughput sequencing revealed the presence of 11 phyla; however, the majority of the sequences were affiliated with four major lineages (Proteobacteria, Bacteroidetes, Actinobacteria and Firmicutes) as confirmed by culture-based methods. Dominant phylotypes were closely related to methylotrophs (Methylobacterium) and bacterial groups able to utilize complex hydrocarbons (Aquabacterium and Dechloromonas). Microbial diversity in biofilms from the 13 m depth was significantly different that in biofilms from 1 to 41 m (P < 0·05). Phylotypes closely related to iron-reducing bacteria were identified at each depth; whereas sulphate-, thio-sulphate-, sulphite- and sulphur-reducing bacteria, at low abundance, were only detected at lower depths. Confocal scanning laser microscopy (CSLM) was used to investigate polymer quantity and composition of the biofilm components, and principal component analysis of the CLSM data revealed that the relative abundance of α-L-fucose and N-acetyl-glucosamine/lipopolysaccharide residues separated tailings-water interface biofilms from those from other depths. Reduced (ferrous) iron was detected within all the biofilm samples examined by scanning X-ray transmission microscopy. CONCLUSIONS: Microbial communities within the water column covering a highly alkaline uranium tailings body form biofilms with microenvironments where iron reduction takes place. SIGNIFICANCE AND IMPACT OF THE STUDY: This study demonstrates the biogeochemical potential of microbial biofilm communities in the water column covering an alkaline uranium tailings body; specifically, the nature of the bacterial groups detected (Aquabacterium, Dechloromonas) and the presence of reduced iron suggest that complex hydrocarbons are available for bacterial growth and geochemical change, such as iron reduction, can occur even though the system bulk phase is predominantly oxic.


Asunto(s)
Bacterias/clasificación , Biopelículas/crecimiento & desarrollo , Minería , Contaminantes Radiactivos del Suelo/metabolismo , Uranio/metabolismo , Microbiología del Agua , Bacterias/genética , Bacterias/aislamiento & purificación , Filogenia
6.
Aliment Pharmacol Ther ; 40(4): 374-81, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24961751

RESUMEN

BACKGROUND: There are limited data regarding clinical outcomes in ulcerative colitis (UC) patients who require early corticosteroids (CS) use. AIM: To evaluate the rate of early CS utilisation (within 30 days of diagnosis) as a predictive marker for long-term outcomes, colectomy and CS dependency, in a population-based cohort of incident UC cases. METHODS: Nationwide data were obtained from the Veterans Affairs (VA) health care system for the period 2001-2011. Incident UC cases were identified. A retrospective cohort design and time-to-event survival analysis were used to track outcomes of interest. Cox regression multivariate analysis was employed. RESULTS: One thousand and thirty-five newly diagnosed patients with UC were identified and included in the analysis; 236 (23%) of those patients required early CS therapy. Patients were followed-up over a median time of 4.7 years (IQR 2.8-6.8) after UC diagnosis. The 5-year cumulative probability of requiring colectomy varied significantly by early CS use status (13% among early CS users compared to 4% among those who did not require early CS treatment, P < 0.001). Similar variation in the 5-year cumulative probability of CS dependency by early CS status was observed. Early CS users were more likely to require colectomy 2.9 (CI 1.7-5.0, P < 0.001) and to become CS dependent 4.5 (95% CI 3.6-5.7, P < 0.001) than non-users. CONCLUSIONS: Early CS use can help identify those patients who have a more active disease course of UC. Recognising this can be among the indicators that can help physicians identify patients who may require early initiation of more aggressive therapy.


Asunto(s)
Colectomía/estadística & datos numéricos , Colitis Ulcerosa/tratamiento farmacológico , Glucocorticoides/uso terapéutico , Adulto , Anciano , Estudios de Cohortes , Colitis Ulcerosa/fisiopatología , Colitis Ulcerosa/cirugía , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Análisis de Regresión , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Análisis de Supervivencia , Factores de Tiempo
7.
Can J Microbiol ; 60(4): 243-9, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24693983

RESUMEN

Lake Diefenbaker (LD) is a large reservoir on the South Saskatchewan River used for agricultural irrigation, drinking water, and recreation. Our objectives were to determine the distribution and abundance of bacterial indicators in embayments and the main channel of LD and to relate these to environmental factors. Total coliforms (TCs), fecal coliforms (FCs), and fecal indicator bacteria (i.e., Escherichia coli) were measured concurrently with water quality parameters. Although TCs, FCs, and E. coli were present in LD, they rarely exceeded the TC and FC Canadian Council of Ministers of the Environment (CCME) water quality standards for agricultural use (1000 colony-forming units (CFU) per 100 mL and 100 CFU per 100 mL, respectively). The correlation between the bacterial indicators in the sediments and the water column indicates that higher embayment abundances may be related to sediment loading and (or) resuspension events in these frequently mixed embayments. With higher water temperatures and water levels, as well as higher microbial activity, CCME bacterial limits may be exceeded. The greatest contributor to bacterial indicator abundance was water temperature. We predict that water quality standards will be exceeded more frequently with climate warming.


Asunto(s)
Enterobacteriaceae/crecimiento & desarrollo , Lagos , Microbiología del Agua , Calidad del Agua/normas , Abastecimiento de Agua/normas , Enterobacteriaceae/aislamiento & purificación , Escherichia coli/crecimiento & desarrollo , Escherichia coli/aislamiento & purificación , Heces/microbiología , Agua Dulce/microbiología , Sedimentos Geológicos/microbiología , Calentamiento Global , Lagos/microbiología , Ríos/microbiología , Saskatchewan , Estaciones del Año , Temperatura
8.
J Appl Microbiol ; 114(6): 1671-86, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23448257

RESUMEN

AIMS: To describe the diversity and metabolic potential of microbial communities in uranium mine tailings characterized by high pH, high metal concentration and low permeability. METHODS AND RESULTS: To assess microbial diversity and their potential to influence the geochemistry of uranium mine tailings using aerobic and anaerobic culture-based methods, in conjunction with next generation sequencing and clone library sequencing targeting two universal bacterial markers (the 16S rRNA and cpn60 genes). Growth assays revealed that 69% of the 59 distinct culturable isolates evaluated were multiple-metal resistant, with 15% exhibiting dual-metal hypertolerance. There was a moderately positive correlation coefficient (R = 0·43, P < 0·05) between multiple-metal resistance of the isolates and their enzyme expression profile. Of the isolates tested, 17 reduced amorphous iron, 22 reduced molybdate and seven oxidized arsenite. Based on next generation sequencing, tailings depth was shown to influence bacterial community composition, with the difference in the microbial diversity of the upper (0-20 m) and middle (20-40 m) tailings zones being highly significant (P < 0·01) from the lower zone (40-60 m) and the difference in diversity of the upper and middle tailings zone being significant (P < 0·05). Phylotypes closely related to well-known sulfate-reducing and iron-reducing bacteria were identified with low abundance, yet relatively high diversity. CONCLUSIONS: The presence of a population of metabolically-diverse, metal-resistant micro-organisms within the tailings environment, along with their demonstrated capacity for transforming metal elements, suggests that these organisms have the potential to influence the long-term geochemistry of the tailings. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is the first investigation of the diversity and functional potential of micro-organisms present in low permeability, high pH uranium mine tailings.


Asunto(s)
Bacterias/clasificación , Minería , Uranio , Bacterias/aislamiento & purificación , Bacterias/metabolismo , Biodiversidad , Biotransformación , Concentración de Iones de Hidrógeno , Hierro/metabolismo , Metales/toxicidad , Datos de Secuencia Molecular , Permeabilidad , Filogenia , ARN Ribosómico 16S/genética , Cloruro de Sodio/toxicidad
9.
Curr HIV Res ; 10(6): 532-8, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22716105

RESUMEN

There is limited information available about the prevalence and pattern of human immunodeficiency virus (HIV) drug resistance mutations (DRMs) among antiretroviral therapy (ART) experienced patients from northern India. Results of genotypic drug resistance testing were obtained from plasma samples of 128 patients, who had presented with clinical or immunological failure to treatment after at least six months of ART. Major DRMs associated with any of the three classes of antiretroviral (ARV) drugs, nucleoside reverse transcriptase inhibitors (NRTI), non-nucleoside reverse transcriptase inhibitors (NNRTI) and protease inhibitors (PI), were seen in 120 out of 128 patients (93.8% prevalence). NRTI and NNRTI DRMs were each seen in 115/128 (89.8%) patients, with M184V, M41L, D67N and T215Y being the most frequent among NRTI associated mutations, and K103N, G190A, Y181C and A98G among NNRTI associated ones. PI DRMs were observed in 14/128 (10.9%) patients, with L10I, V82A and L89V being the commonest. These results present a high prevalence of DRMs among ART experienced patients from northern India with clinical or immunological failure of therapy. It emphasizes the need for regular testing of plasma samples of such patients for DRMs in order to detect and replace a failing regimen early, and also the use of HIV drug resistance genotyping of ART naive individuals prior to initiating first line ART for possible transmitted resistance. It is very important to enhance the access of patients to ARV drugs so that their compliance could be improved and hence development of DRMs be minimized.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/genética , Fármacos Anti-VIH/administración & dosificación , Farmacorresistencia Viral/genética , VIH-1/genética , VIH-1/inmunología , Inhibidores de Proteasas/administración & dosificación , Inhibidores de la Transcriptasa Inversa/administración & dosificación , Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Síndrome de Inmunodeficiencia Adquirida/epidemiología , Adulto , Femenino , Genotipo , VIH-1/efectos de los fármacos , Humanos , India/epidemiología , Masculino , Filogenia , Prevalencia , Insuficiencia del Tratamiento
10.
Obstet Gynecol ; 115(6): 1225-1232, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20502294

RESUMEN

OBJECTIVE: To estimate the effects of chlorhexidine vaginal and baby wipes on fetal and neonatal mortality, respectively, and infection-related morbidity. METHODS: We performed a placebo-controlled, randomized trial of chlorhexidine vaginal and neonatal wipes to reduce neonatal sepsis and mortality in three hospitals in Pakistan. The primary study outcome was a composite of neonatal sepsis or 7-day perinatal mortality. RESULTS: From 2005 to 2008, 5,008 laboring women and their neonates were randomly assigned to receive either chlorhexidine wipes (n=2,505) or wipes with a saline placebo (n=2,503). The primary outcome was similar in the chlorhexidine and control groups (3.1% compared with 3.4%; relative risk 0.91, 95% confidence interval 0.67-1.24) as was the composite rate of neonatal sepsis or 28-day perinatal mortality (3.8% compared with 3.9%, relative risk 0.96, 95% confidence interval 0.73-1.27). At day 7, the chlorhexidine group had a lower rate of neonatal skin infection (3.3% compared with 8.2%, P<.001). With the exception of less frequent 7-day hospitalization in the chlorhexidine group, there were no significant differences in maternal outcomes between the groups. CONCLUSION: Using maternal chlorhexidine vaginal wipes during labor and neonatal chlorhexidine wipes does not reduce maternal and perinatal mortality or neonatal sepsis. The finding of reduced superficial skin infections on day 7 without change in sepsis or mortality suggests that this difference, although statistically significant, may not be of major importance. LEVEL OF EVIDENCE: I.


Asunto(s)
Antiinfecciosos Locales/uso terapéutico , Clorhexidina/uso terapéutico , Enfermedades del Recién Nacido/mortalidad , Enfermedades del Recién Nacido/prevención & control , Sepsis/prevención & control , Adulto , Países en Desarrollo , Femenino , Humanos , Recién Nacido , Enfermedades del Recién Nacido/microbiología , Pakistán/epidemiología , Embarazo , Sepsis/mortalidad , Adulto Joven
11.
Chirality ; 21(2): 255-61, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18561251

RESUMEN

Chromatographic behavior of nonracemic mixtures, viz., mandelic acid and stilbene oxide as analytes has been studied in detailed by enantiomer self-disproportionation on achiral ordered mesoporous material M41S and regular silica gel as stationary phases. Enantiomer self-disproportionation gave enhanced separation of analytes. The extent and magnitude of enantiomer self-disproportionation is dependent on the optical purity of the starting non-racemic molecules, presence of intermolecular hydrogen bonding/pi-pi interactions and the nature of eluents used. The present study and previous literature data suggest that percentage ee of a nonracemic mixture needs to be determined before any chromatographic purification is taken up as enantiomer self-disproportionation phenomenon could occur during purification. The data show that enantiomer self-disproportionation of nonracemic mixtures can be harnessed for its enantioenrichment on inexpensive achiral stationary phases.


Asunto(s)
Cromatografía en Gel/métodos , Dióxido de Silicio/química , Enlace de Hidrógeno , Ácidos Mandélicos/análisis , Ácidos Mandélicos/aislamiento & purificación , Porosidad , Gel de Sílice , Solventes/química , Estereoisomerismo , Estilbenos/análisis , Estilbenos/aislamiento & purificación , Propiedades de Superficie , Temperatura
12.
J Chromatogr A ; 1191(1-2): 223-30, 2008 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-18325527

RESUMEN

Novel chiral stationary phase (CSP) based on chiral aminoalcohol immobilized on ordered mesoporous silica SBA-15 1a and standard silica 1b and their copper complexes 1a' and 1b', respectively, was synthesized as potential material for chiral ligand exchange chromatography (CLEC). Microanalysis, inductively coupled plasma spectroscopy (ICP), thermo-gravimetric analysis (TGA), cross polarized magic angle spinning (CP-MAS) (13)C NMR, Powder X-ray diffraction (PXRD), FTIR, N(2) adsorption isotherm, scanning electron microscopy (SEM), transmitted electron microscope (TEM) and solid reflectance UV-vis spectroscopy were used to characterize these materials. All the chiral stationary phases thus synthesized were used for the separation of different racemic compounds such as mandelic acid, 2,2'-dihydroxy-1,1'-binaphthalene BINOL) and diethyl tartrate by simple medium-pressure column chromatography. Successful enantio-separation of racemic mandelic acid was achieved with all the stationary phases but 1a and 1b gave slightly better resolution than their copper complexes 1a' and 1b'. Remarkably these materials are stable under the given experimental conditions and can be used repeatedly for several cycles of enantioresolution. It was observed that the porosity and surface area of the stationary phase play an important role in the chiral separation.


Asunto(s)
Dióxido de Silicio/síntesis química , Amino Alcoholes/química , Cromatografía Liquida/instrumentación , Cromatografía Liquida/métodos , Cobre/química , Dióxido de Silicio/química , Estereoisomerismo
13.
J Chromatogr A ; 1135(2): 186-93, 2006 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-17055521

RESUMEN

A new chiral stationary phase (CSP) was synthesized based on (S)-1-anilino-3-propyl-2-propanol covalently bonded to the mesoporous semi-crystalline material M41S. Direct semipreparative enantioseparation of mandelic acid could be achieved using medium pressure chromatography. Partly separated could also be the enantiomers of 2,2'-dihydroxy-1,1'-binaphthalene, cyanochromene oxide, diethyl tartrate and 2-phenyl propionic acid. The characterization of CSP was accomplished by microanalysis, cross polarized magic angle spinning (CP-MAS) 13C NMR, powder X-ray diffraction (XRD), FTIR, thermo-gravimetric analysis (TGA), N2 adsorption-desorption isotherm, scanning electron microscopy (SEM) and solid reflectance UV-vis spectroscopy. Furthermore the stability of CSP was satisfactory as it could withstand three washing and reuse experiments of enantioseparation of mandelic acid without loss in its performance.


Asunto(s)
Amino Alcoholes/química , Espectroscopía de Resonancia Magnética , Microscopía Electrónica de Rastreo , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Estereoisomerismo , Difracción de Rayos X
14.
Anim Reprod Sci ; 54(3): 149-57, 1999 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-10066102

RESUMEN

The objective of this study was to develop a simple and portable CO2 incubator using effervescent granules (EG) and to examine the effect of negative and positive air pressure for in vitro maturation (IVM), fertilization (IVF) and culture (IVC) of bovine oocytes. In experiment 1, cumulus-oocyte complexes (COCs) were matured (22 h), fertilized (5 h) and cultured (7 days) using 0.25, 0.5 or 1.0 g of EG per 0.6 l added to maintain an optimum level of CO2 (approximately 3, 6 or 12%, respectively) for in vitro production of embryos. Control oocytes, zygotes and embryos were cultured in a standard CO2 incubator. The blastocyst production rates observed on Days 7 to 9 after insemination were 20.5+/-4.2%, 18.5+/-3.9% and 28.7+/-5.1% for the 0.25 g EG, 0.5 g EG treatments and control, respectively. These rates were significantly higher (P < 0.05) than that of the 1.0 g EG treatment (8.7+/-2.6%). The number of cells in the inner cell mass (ICM) and trophectoderm (TE) produced from blastocysts using the control procedure were 40.8+/-2.9 and 81.2+/-5.3, respectively, and were higher (P < 0.05) compared to the 0.50 g EG (34.6+/-2.9 and 66.8+/-5.7) and 1.0 g EG treatments (33.4+/-3.4 and 67.2+/-7.3). In experiment 2, COCs were placed in a small box with 0.25 g of EG so that the effects on IVM, IVF and IVC of positive or negative air pressure could be compared. The blastocyst production rate observed in the negative air pressure treatment (29.6+/-4.6%) was higher (P < 0.01) than that of the positive air pressure treatment (6.2+/-1.5%) or the normal treatment pressure (P < 0.05; 18.7+/-4.2%) but did not differ from that of the control (30.7+/-4.4%). These results indicate that this simple type of incubator with negative air pressure can be successfully used for in vitro production of bovine embryos and could be used at the field level.


Asunto(s)
Bovinos/embriología , Desarrollo Embrionario y Fetal/fisiología , Incubadoras/veterinaria , Presión del Aire , Animales , Dióxido de Carbono/fisiología , Femenino , Fertilización In Vitro/veterinaria , Masculino , Oocitos/fisiología , Interacciones Espermatozoide-Óvulo/fisiología , Espermatozoides/fisiología
15.
Am J Sports Med ; 26(1): 20-9, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9474397

RESUMEN

We retrospectively reviewed the results of 97 patients with anterior cruciate ligament reconstructions using an arthroscopically assisted two-incision technique without extraarticular augmentation at an intermediate followup of 5 to 9 years postoperatively. Evaluation included detailed history, physical examination, functional testing, KT-1000 arthrometer measurements, multiple scoring systems, and radiographs. The results were compared with those from a previous study that evaluated a smaller patient cohort using the identical surgical technique at a 2- to 4-year followup. The postoperative physical examination and KT-1000 arthrometer results were statistically improved when compared with preoperative findings. A negative pivot shift result was noted in 83% of patients, and a 1+ result in 17% of patients. Seventy percent of patients had < 3 mm difference on manual maximum side-to-side testing. Functional testing averaged less than 2% asymmetry for vertical jump, single-legged hop, or timed 6-meter hop. The Tegner activity level was significantly improved from prereconstruction ratings and similar to preinjury ratings. The mean Lysholm score was 87. The modified Hospital for Special Surgery scores resulted in good or excellent results in 82% of the patients (mean, 87 points). The mean Noyes sports function score was 89, and the reoperation rate for a symptomatic knee flexion contracture was 12%. Ninety-seven percent of patients indicated that they would undergo the procedure again. When compared with this same population at 2 to 4 years, we saw no deterioration in scoring scale results.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Ligamento Cruzado Anterior/cirugía , Endoscopía , Traumatismos de la Rodilla/cirugía , Tendones/trasplante , Adolescente , Adulto , Artroscopía , Niño , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Estudios Retrospectivos , Rotura , Trasplante Autólogo , Resultado del Tratamiento
16.
Am J Sports Med ; 26(1): 30-40, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9474398

RESUMEN

We conducted a retrospective, minimum 2-year follow-up study to evaluate the effectiveness of a single-incision endoscopic anterior cruciate ligament reconstruction technique using patellar tendon autograft without extraarticular augmentation and followed by accelerated rehabilitation. One hundred three patients were evaluated (mean followup, 36 months; range, 24 to 55). There were significant improvements in physical examination test results (Lachman, anterior drawer, and pivot shift) postoperatively, and 94 patients (91%) had negative pivot shift results. KT-1000 arthrometric testing showed a significant reduction in manual maximum anterior translation and side-to-side differences at followup. Good range of motion was achieved. Patients with asymmetric prone heel heights usually had hyperextension in the contralateral knee. Functional tests showed 4% to 6% differences in side-to-side comparisons for a timed single-legged hop, single-legged hop for distance, and vertical jump. Postoperatively, the results of the Tegner scale were similar to preinjury scores. The mean results of the Hospital for Special Surgery scale (90), Lysholm score (89), and Noyes sport function score (90) were all excellent or good. Only 5 patients (5%) required reoperations for flexion contractures. Ninety-six patients (93%) reported they were "mostly" or "completely" satisfied, and 98 (95%) would recommend the procedure to others. These results demonstrated encouraging outcome using this single-incision technique.


Asunto(s)
Lesiones del Ligamento Cruzado Anterior , Ligamento Cruzado Anterior/cirugía , Endoscopía , Traumatismos de la Rodilla/cirugía , Tendones/trasplante , Adolescente , Adulto , Artroscopía , Niño , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Rótula , Rotura , Trasplante Autólogo
17.
J Urol ; 151(6): 1607-9, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8189574

RESUMEN

We report a case of renal cell carcinoma that showed extensive osteosarcomatous differentiation and simulated a staghorn calculus clinically and radiologically. The literature on osteosarcomatous differentiation in renal cell carcinoma is reviewed.


Asunto(s)
Carcinoma de Células Renales/diagnóstico , Cálculos Renales/diagnóstico , Neoplasias Renales/diagnóstico , Pelvis Renal , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Osteosarcoma/patología
19.
J Pak Med Assoc ; 43(9): 174-6, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8283595

RESUMEN

Fifty cases of uterine rupture were managed in 4 years giving a frequency of 1 per 89.9 deliveries. There was an obvious difference between those with a previously scarred uterus (34) vs those without a scar (16) cephalopelvic disproportion, grand multiparity and mismanagement of cases by traditional birth attendant (TBAs) were the common etiologic factors in the unscarred uterus, cephalopelvic disproportion, forceps delivery, grand multiparity and prolonged first stage of labour were the common etiologic factors in patients with previously scarred uterus. In the unscarred group both maternal and foetal (81.6%) mortality was high (JPMA 43: 174, 1993).


Asunto(s)
Rotura Uterina , Adulto , Femenino , Muerte Fetal , Humanos , Pakistán , Embarazo , Rotura Uterina/epidemiología , Rotura Uterina/etiología
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