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1.
Food Chem ; 275: 610-617, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30724240

RESUMEN

Soybean plants of the variety 'MG/BR Conquista' were grown in open top chambers, simulating elevated CO2 concentration ([CO2]) and high temperature under the following treatments: 1) ambient [CO2] and ambient temperature (Amb); 2) elevated [CO2] (eCO2) and ambient temperature (Elev); 3) ambient [CO2] and high temperature (Amb/Temp); 4) elevated CO2 and high temperature (Elev/Temp). The aim was to evaluate responses to elevated [CO2] and high temperature, with focus on plant development and seed yield, and composition. Elev stimulated grain yield and Amb/Temp had opposite effect. Several biochemical parameters were affected by Amb/Temp, most of them reversed by simultaneous application of Elev. The oil obtained with Elev/Temp had lower degree of unsaturation. A network of relationships among biochemical parameters of grains at three developmental stages revealed that Amb/Temp and Elev/Temp affect significantly both carbohydrate and lipid metabolisms. No significant difference was obtained comparing networks corresponding to Amb and Elev/Temp.


Asunto(s)
Biomasa , Dióxido de Carbono/farmacología , Glycine max/efectos de los fármacos , Carbohidratos/química , Carbono/química , Carbono/metabolismo , Grano Comestible/metabolismo , Ácidos Grasos/química , Ácidos Grasos/metabolismo , Nitrógeno/química , Nitrógeno/metabolismo , Semillas/efectos de los fármacos , Semillas/metabolismo , Glycine max/química , Glycine max/metabolismo , Temperatura
2.
Environ Pollut ; 147(3): 691-5, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17116349

RESUMEN

Psidium guajava 'Paluma' saplings were exposed to carbon filtered air (CF), ambient non-filtered air (NF), and ambient non-filtered air+40ppb ozone (NF+O(3)) 8h per day during two months. The AOT40 values at the end of the experiment were 48, 910 and 12 895ppbh(-1), respectively for the three treatments. After 5 days of exposure (AOT40=1497ppbh(-1)), interveinal red stippling appeared in plants in the NF+O(3) chamber. In the NF chamber, symptoms were observed only after 40 days of exposure (AOT40=880ppbh(-1)). After 60 days, injured leaves per plant corresponded to 86% in NF+O(3) and 25% in the NF treatment, and the average leaf area injured was 45% in NF+O(3) and 5% in the NF treatment. The extent of leaf area injured (leaf injury index) was explained mainly by the accumulated exposure of ozone (r(2)=0.91; p<0.05).


Asunto(s)
Oxidantes Fotoquímicos/análisis , Ozono/análisis , Psidium/química , Brasil , Exposición a Riesgos Ambientales/efectos adversos , Monitoreo del Ambiente/métodos , Hojas de la Planta/química , Hojas de la Planta/efectos de los fármacos , Psidium/efectos de los fármacos , Clima Tropical
3.
Phytochemistry ; 55(6): 581-7, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11130668

RESUMEN

The distribution of polysaccharides from the seed cell walls of 57 samples of Vochysiaceae native to Brazil were studied, comprising 16 species distributed among the genera Callisthene, Qualea, Salvertia and Vochysia. The polysaccharides were extracted with hot water, then hydrolyzed with the resulting monomers analyzed by HPLC. All samples yielded arabinose, galactose, glucose. mannose and rhamnose, the relative amounts of each monomer, however, varying from one sample to another. Arabinose was always the predominant component, which implies that it might possibly be used as a marker of the Vochysiaceae. The quantitative distribution of monosaccharides was similar between the species of Qualea and Callisthene, characterized by the predominance of arabinose and mannose, and between the species of Salvertia and Vochysia, which contained higher amounts of arabinose and galactose. Such results are consistent with affinities inferred from floral morphology, wood anatomy and molecular data. Substantial intraspecific variation was observed for some species. UPGMA analysis based on the distribution of the monosaccharides reveals two main clusters, according to the links commented above. The resultant phenogram is not coherent with the current sectional classification of the Vochysiaceae, but the differences in the monosaccharides distribution between the two clusters are strongly supported by ANOVA.


Asunto(s)
Polisacáridos/análisis , Rosales/clasificación , Semillas/química , Pared Celular/química , Análisis por Conglomerados , Filogenia , Extractos Vegetales/química , Polisacáridos/clasificación , Rosales/química , Solubilidad , Agua/química
4.
Minerva Med ; 80(2): 169-71, 1989 Feb.
Artículo en Italiano | MEDLINE | ID: mdl-2927708

RESUMEN

The results achieved in the treatment of 160 cases of spontaneous pneumothorax in 1976-1986 are examined. Pleural aspiration drainage was practised in 141 cases and produced a permanent cure. 5 cases were surgically treated. Hospitalisation time was less than 16 days in 110 cases.


Asunto(s)
Neumotórax/terapia , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Succión , Factores de Tiempo , Cicatrización de Heridas
5.
Minerva Med ; 79(12): 1053-6, 1988 Dec.
Artículo en Italiano | MEDLINE | ID: mdl-2850513

RESUMEN

Four-hundred and thirty-six patients recognized affected by primitive lung neoplasia have been examined to prove possible correlation between the endoscopic aspects, histologic type and central or peripheral localization of the neoplasia. The diagnostic sensibility of the different cytohistological techniques used in fiberoptic bronchoscopy have been valued too. For the peripheral localizations the diagnosis has been obtained in most cases by using fine needle percutaneous aspiration.


Asunto(s)
Adenocarcinoma/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Células Pequeñas/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Neoplasias Pulmonares/diagnóstico , Adenocarcinoma/patología , Adenocarcinoma Bronquioloalveolar/diagnóstico , Adenocarcinoma Bronquioloalveolar/patología , Adulto , Anciano , Biopsia con Aguja , Broncoscopía , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Células Pequeñas/patología , Carcinoma de Células Escamosas/patología , Citodiagnóstico , Femenino , Humanos , Pulmón/patología , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
6.
Z Naturforsch C J Biosci ; 55(9-10): 688-92, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11098816

RESUMEN

The epicuticular waxes of leaves of four species (Aspidosperma pyrifolium, Capparis yco, Maytenus rigida and Ziziphus joazeiro) from the Caatinga, (a semi-arid ecosystem of Northeast Brazil) and four species (Aristolochia esperanzae, Didymopanax vinosum, Strychnos pseudoquina and Tocoyena formosa) from the Cerrado, (a savanna ecosystem covering one third of the Brazilian territory), were analyzed. Six species contained a high content (above 60 microg x cm(-2)) of wax, four of them from the Caatinga. Triterpenoids and n-alkanes were the most frequent and abundant constituents found in the species from both habitats. The distribution of n-alkanes predominated by homologues with 27, 29, 31 and 33 carbon atoms, displayed no consistent differences between species from the two habitats. Lupeol, beta-amyrin, epifriedelinol and ursolic acid were the triterpenoids found. Triterpenoids clearly predominate over alkanes in the waxes from the Cerrado species. The waxes of two evergreen species from the Caatinga yielded n-alkanes as predominant constituents. A comparison of foliar epicuticular waxes of native plants from ecosystems with different hydric constraints is discussed.


Asunto(s)
Hojas de la Planta/química , Plantas/química , Ceras/química , Alcoholes/análisis , Alcanos/análisis , Asteraceae/química , Brasil , Clima , Clima Desértico , Ecosistema , Ácidos Grasos/análisis , Cetonas/análisis , Rosales/química , Especificidad de la Especie , Triterpenos/análisis , Ceras/aislamiento & purificación
7.
Biochem Syst Ecol ; 28(6): 545-550, 2000 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-10793254

RESUMEN

Flavonoids of 11 samples of Cercis, comprising seven species, were isolated and identified. Only 3-O-monoglycosides of kaempferol, quercetin and myricetin were obtained. Bauhinia (the largest genus in tribe Cercideae) is akin to Cercis because flavones are rarely found in the former. On the other hand, species of Bauhinia often present glycosides of isorhamnetin and a wider diversity of glycosides, and only rarely present myricetin. The frequent occurrence of this flavonol and the simpler flavonoid profile of Cercis may reflect a greater antiquity of Cercis as compared with Bauhinia. With the exception of C. canadensis var. mexicana, Cercis taxa from xerophytic habitats did not yield kaempferol glycosides in detectable amounts, as opposed to taxa from mesophytic habitats. The results obtained are consistent with proposals of merging C. reniformis into synonymy of C. occidentalis, as well as the recognition of two North American species, C. canadensis and C. occidentalis, and the recognition of the Asian C. gigantea.

8.
Biochem Syst Ecol ; 29(7): 711-726, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11399358

RESUMEN

Leaves of species of three closely related genera of Melastomataceae, Lavoisiera, Microlicia and Trembleya were analyzed for their flavonoid composition. A total of 116 compounds were obtained, comprising 69 flavonol and 47 flavone glycosides. The common occurrence of flavones, including 6-oxygenated derivatives, characterize Lavoisiera (which often yielded methoxylated flavonols and flavones). Flavonols predominate in species of Microlicia. The flavonoid patterns of Trembleya are rather confusing, some species being akin to Lavoisiera, others to Microlicia. UPGMA analysis using the flavonoid aglycones as characters and the samples analyzed as OTUs gives no complete resolution for the three genera, but provides clusters combining exclusively or preferentially species of either Lavoisiera and Microlicia. Species of Trembleya emerge from the phenogram interspersed among species of the other genera. The data suggest the recognition of Lavoisiera and Microlicia and the lumping of species of Trembleya with either of these genera. If greater flavone diversity is viewed as indicative of further evolutionary advancement, shrubby habits in Microliceae (Lavoisiera and Trembleya) should be regarded as derived from herbaceous ones (Microlicia).

9.
Artículo en Inglés | MEDLINE | ID: mdl-23690840

RESUMEN

Propolis is a complex honeybee product with resinous aspect, containing plant exudates and beeswax. Their color, texture, and chemical composition vary, depending on the location of the hives and local flora. The most studied Brazilian propolis is the green (alecrim-do-campo) type, which contains mainly prenylated phenylpropanoids and caffeoylquinic acids. Other types of propolis are produced in Brazil, some with red color, others brown, grey, or black. The aim of the present work was to determine the chemical profiles of alcohol and chloroform extracts of eight samples of propolis, corresponding to six Brazilian regions. Methanol and chloroform extracts were obtained and analyzed by HPLC/DAD/ESI/MS and GC/MS. Two chemical profiles were recognized among the samples analyzed: (1) black Brazilian propolis, characterized chiefly by flavanones and glycosyl flavones, stemming from Picos (Piauí state) and Pirenópolis (Goiás state); (2) green Brazilian propolis, characterized by prenylated phenylpropanoids and caffeoylquinic acids, stemming from Cabo Verde (Bahia state), Lavras and Mira Bela (Minas Gerais state), Pariquera-Açu and Bauru (São Paulo state), and Ponta Grossa (Paraná state). The present work represents the first report of prenylated flavonoids in Brazilian propolis and schaftoside (apigenin-8-C-glucosyl-6-C-arabinose) in green propolis.

10.
Artículo en Inglés | MEDLINE | ID: mdl-23662146

RESUMEN

The cytotoxic activities of extracts of four samples of propolis from the state of Minas Gerais (Southeast Brazil) and two from the state of Paraná (South Brazil) were evaluated using sea urchin (Lytechinus variegatus) eggs. Cytotoxic activity was observed, characterized mainly by the inhibition of the first cleavage of newly fertilized eggs. Methanol extracts at 32 µg mL(-1) of all samples were highly active (97-100%). Extracts were also prepared by successive treatments of the samples with hexane, chloroform, ethyl acetate, and methanol. High activity was observed using the ethyl acetate fractions of all samples, but hexane and chloroform fractions of some samples also had high activity. Based on the chemical composition of the extracts and fractions (published previously), it is hypothesized that the cytotoxic activities observed are due mainly to artepillin C, p-coumaric acid, and kaempferide. The results suggest that caffeoylquinic acids have no cytotoxic activity in sea urchin eggs.

11.
Breast ; 22(6): 1136-41, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23958374

RESUMEN

PURPOSE: The aim of this paper is to analyze the incidence of acute and late toxicity and cosmetic outcome in breast cancer patients submitted to breast conserving surgery and three-dimensional conformal radiotherapy (3D-CRT) to deliver accelerated partial breast irradiation (APBI). METHODS AND MATERIALS: 84 patients were treated with 3D-CRT for APBI. This technique was assessed in patients with low risk stage I breast cancer enrolled from September 2005 to July 2011. The prescribed dose was 34/38.5 Gy delivered in 10 fractions twice daily over 5 consecutive days. Four to five no-coplanar 6 MV beams were used. In all CT scans Gross Tumor Volume (GTV) was defined around the surgical clips. A 1.5 cm margin was added by defining a Clinical Target Volume (CTV). A margin of 1 cm was added to CTV to define the planning target volume (PTV). The dose-volume constraints were followed in accordance with the NSABP/RTOG protocol. Late toxicity was evaluated according to the RTOG grading schema. The cosmetic assessment was performed using the Harvard scale. RESULTS: Median patient age was 66 years (range 51-87). Median follow-up was 36.5 months (range 13-83). The overall incidence of acute skin toxicities was 46.4% for grade 1 and 1% for grade 2. The incidence of late toxicity was 16.7% for grade 1, 2.4% for grade 2 and 3.6% for grade 3. No grade 4 toxicity was observed. The most pronounced grade 2 late toxicity was telangiectasia, developed in three patients. Cosmetics results were excellent for 52%, good for 42%, fair for 5% and poor for 1% of the patients. There was no statistical correlation between toxicity rates and prescribed doses (p = 0.33) or irradiated volume (p = 0.45). CONCLUSIONS: APBI using 3D-CRT is technically feasible with very low acute and late toxicity. Long-term results are needed to assess its efficacy in reducing the incidence of breast relapse.


Asunto(s)
Neoplasias de la Mama/radioterapia , Carcinoma Ductal de Mama/radioterapia , Traumatismos por Radiación/etiología , Radioterapia Conformacional/efectos adversos , Piel/efectos de la radiación , Tejido Adiposo/patología , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/cirugía , Carcinoma Ductal de Mama/cirugía , Fraccionamiento de la Dosis de Radiación , Estética , Femenino , Humanos , Hiperpigmentación/etiología , Persona de Mediana Edad , Necrosis/diagnóstico por imagen , Necrosis/etiología , Dolor/etiología , Radiografía , Planificación de la Radioterapia Asistida por Computador , Radioterapia Conformacional/métodos , Telangiectasia/etiología
12.
Oral Oncol ; 48(3): 266-71, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22079100

RESUMEN

In loco-regionally advanced head and neck squamous cell cancer (HNSCC), concurrent 3-weekly cisplatin improves overall survival (OS) compared to radiotherapy alone, but is often associated with renal toxicity. The use of radiotherapy with accelerated fractionation schedules has been reported to improve survival but its optimal combination with chemotherapy is unclear. Retrospective analysis of treatment outcome and nephrotoxicity of radiotherapy given with an intensity-modulated approach (IMRT) concurrent with either 3-weekly or weekly cisplatin in 94 patients with stage III/IV HNSCC. Patients treated with weekly cisplatin were significantly older (p=0.0014) and received a significantly lower total cisplatin dose (p=0.0002). With a median follow-up of 2.8 years, at univariate analysis, 3-weekly cisplatin shows a longer OS (p=0.041) but progression-free survival (PFS) is similar for both schedules (p=0.47). Cisplatin doses >240 mg/m(2) were associated with better OS but not PFS. Chronic renal failure rate was significantly higher with 3-weekly cisplatin (p=0.04). Multivariate analysis (Cox regression controlling for age) confirmed the significant and independent impact of alcohol and smoking habits on both PFS (HR, 2.2) and OS (HR, 2.3), while the treatment schedule affected only OS (HR, 2.2). Weekly cisplatin is less nephrotoxic. Both schedules can be combined to curative IMRT. PFS was not significantly different even if patients treated with the weekly schedule were significantly older and received reduced cisplatin doses. The study suggests that the different cisplatin dose doesn't affect the PFS results if concomitant to IMRT. Controlled prospective studies are needed.


Asunto(s)
Antineoplásicos/administración & dosificación , Carcinoma de Células Escamosas/tratamiento farmacológico , Cisplatino/administración & dosificación , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Lesión Renal Aguda/inducido químicamente , Adulto , Anciano , Antineoplásicos/efectos adversos , Carcinoma de Células Escamosas/radioterapia , Cisplatino/efectos adversos , Terapia Combinada/métodos , Supervivencia sin Enfermedad , Femenino , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Masculino , Persona de Mediana Edad , Radioterapia de Intensidad Modulada , Estudios Retrospectivos , Resultado del Tratamiento
13.
Biochem Syst Ecol ; 28(5): 487-488, 2000 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-10725605
18.
Mol Ecol Resour ; 8(5): 1114-6, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21585988

RESUMEN

Epidendrum puniceoluteum is an endemic orchid of Atlantic Rainforest, restricted to few populations only due to the destruction and fragmentation of its native habitat. Here, we report on the development of 10 microsatellite markers isolated from this orchid species. Genetic variability was characterized in two distant populations from Brazil coast. The number of alleles observed for each locus ranged from two to 12 and with an average of 6.4 alleles per locus. These microsatellites should be valuable tools for studying both fine-scale genetic structure of scattered E. puniceoluteum population and patterns will be useful genetic markers for other closely related taxa.

19.
J Nat Prod ; 55(6): 800-3, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1522421

RESUMEN

Ursolic acid from Jacaranda decurrens showed toxicity and feeding deterrency towards the greenbug Schizaphis graminum. Biological activity was determined by analyzing ursolic acid effects on the survival, reproductive index, and population growth rate of the greenbug. Survival and reproductive index decreased in direct proportion to ursolic acid content in the diet. The population growth rate decreased markedly when the aphids were fed on barley leaves sprayed with ursolic acid dissolved in DMSO, in comparison to leaves sprayed only with DMSO. The feeding behavior of the greenbug was also affected by ursolic acid. Ingestion time on diet with 0.1 mM was reduced about 30% in relation to the ingestion time on control diet.


Asunto(s)
Áfidos/fisiología , Plantas Tóxicas/química , Triterpenos/toxicidad , Animales , Brasil , Dimetilsulfóxido/farmacología , Conducta Alimentaria/efectos de los fármacos , Hordeum , Ninfa , Población , Reproducción/efectos de los fármacos , Triterpenos/química , Triterpenos/aislamiento & purificación , Ácido Ursólico
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