Contribution du traitement des images-satellite à la cartographie des pâturages sahéliens

Certains pâturages sahéliens se sont considérablement dégradés au cours des années de sécheresse 1972-1973. Face à cette situation, il est devenu indispensable de procéder à d'importants travaux d'inventaires actualisés des ressources fourragères. Ces inventaires concernent des superficies de plus en plus vastes et s'orientent vers l'étude de l'évolution des parcours. Les images-satellites offrent une solution à quelques-uns des problèmes nouveaux posés par l'étude de régions immenses à des périodes successives. Mais l'interprétation des images-satellite exige une approche globale au travers d'unités synthétiques: les Unités Paysages Pastorales. Traitées par informatique à 1/100 000, les images-satellite permettent d'importants travaux de reconnaissance. Employées conjointement avec des observations de terrain et des photographies aériennes, elles rendent possible la cartographie actualisée des ressources pastorale

Structural organisation of the type IV secretion systems

Type IV secretion (T4S) systems are large dynamic nanomachines that transport DNAs and/or proteins through the membranes of bacteria. Because of their complexity and multi-protein organisation, T4S systems have been extremely challenging to study structurally. However in the past five years significant milestones have been achieved by X-ray crystallography and cryo-electron microscopy. This review describes some of the more recent advances: the structures of some of the protein components of the T4S systems and the complete core complex structure that was determined using electron microscopy

Evaluación de la actividad biológica de productos herbolarios comerciales

Antecedentes: En México los productos herbolarios se comercializan mayormente sin ningún control de calidad, lo cual fue evidenciado recientemente por nuestro grupo de investigación. Objetivo: Evaluar la actividad biológica de diversos productos, considerando el uso tradicional de las plantas que contienen. Material y métodos: Los productos fueron adquiridos comercialmente tanto en hierberías como en centros comerciales. Se obtuvieron extractos hidroalcohólicos por maceración a temperatura ambiente y extractos acuosos por ebullición. Se evaluaron la actividad antioxidante (DPPH) antimicrobiana contra S. aureus, E. coli y C. albicans (microdilución en placa), antihipertensiva (inhibición de la enzima convertidora de angiotensina) e inmunomoduladora de los extractos obtenidos. Resultados: Los productos que contenían Peumus boldus, Turnera diffusa, Eucalyptus globulus, Ginkgo biloba y Agastache mexicana resultaron con buena actividad antioxidante, los demás mostraron actividad antioxidante baja o moderada. P. boldus, E. globulus y Salvia officinalis mostraron buena actividad antimicrobiana; sin embargo, los productos analizados de Allium sativum y Mentha piperita, reconocidos tradicionalmente por sus propiedades antisépticas, no mostraron actividad contra los microorganismos utilizados. Los productos comerciales con A. sativum o con Esquisetum arvense, que se recomiendan como diuréticos, no mostraron efecto en la prueba utilizada. Conclusiones: Los resultados de esta investigación demuestran que distintos productos que dicen contener la misma planta producen diferentes grados de actividad biológica. Se hace necesario un estricto control de calidad de los productos herbolarios que evalúe también la actividad biológica, con el fin de prevenir problemas en la salud de la población que los consume

Antimicrobial and Antioxidant Activities of Plants from Northeast of Mexico

Traditional medicine has a key role in health care worldwide. Obtaining scientific information about the efficacy and safety of the plants from our region is one of the goals of our research group. In this report, 17 plants were selected and collected in different localities from northeast Mexico. The dried plants were separated into leaves, flowers, fruit, stems, roots and bark. Each part was extracted with methanol, and 39 crude extracts were prepared. The extracts were tested for their antimicrobial activity using three Gram-negative bacterial strains (Pseudomonas aeruginosa, Klebsiella pneumoniae and Acinetobacter baumannii), three Gram-positive bacterial strains (Enterococcus faecalis and two Staphylococcus aureus strains), and seven clinically isolated yeasts (Candida albicans, C. krusei, C. tropicalis, C. parapsilosis and C. glabrata); their antioxidant activity was tested using a DPPH free radical assay. No activity against Gram-negative bacteria was observed with any extract up to the maximum concentration tested, 1000 μg ml−1. We report here for the first time activity of Ceanothus coeruleus against S. aureus (flowers, minimal inhibitory concentration (MIC) 125 μg ml−1), C. glabrata (MICs 31.25 μg ml−1) and C. parapsilosis (MICs between 31.25 and 125 μg ml−1); Chrysanctinia mexicana against C. glabrata (MICs 31.25 μg ml−1); Colubrina greggii against E. faecalis (MICs 250 μg ml−1) and Cordia boissieri against C. glabrata (MIC 125 μg ml−1). Furthermore, this is the first report about antioxidant activity of extracts from Ceanothus coeruleus, Chrysanctinia mexicana, Colubrina greggii and Cyperus alternifolius. Some correlation could exist between antioxidant activity and antiyeast activity against yeasts in the species Ceanothus coeruleus, Schinus molle, Colubrina greggii and Cordia boissieri

Review of plants with hepatoprotective activity evaluated in Mexico

Liver diseases represent a major health problem around the world. in Mexico these are the 5th leading cause of death in the economically active population. in Mexico, it is estimated that about 60% of the population uses some medicine from plants to treat their illnesses. The purpose of this work was to search for medicinal plants in Mexico that have been evaluated for their hepatoprotective effect in different models. in this review we found only 13 plants evaluated for hepatoprotective activity: Amole tuber, Cochlospermum vitifolium, Heterotheca inuloides, Hibiscus sabdariffa, Leucophyllum frutescens, Prostechea michuacana, Psidium Guajava, Rosmarinus officinalis, Verbena Carolin, Centaurea americana, Juglans mollis, Krameria ramossisima and Turnera diffusa. This study describes the studies conducted in Mexico for each of them and the international literature reports of pharmacological and phytochemical studies

2,2′-Dimethoxy-4,4′-[rel-(2R,3S)-2,3-di­methylbutane-1,4-diyl]diphenol

The title mol­ecule, C20H26O4, commonly known as meso-dihydro­guaiaretic acid, is a naturally occurring lignan extracted from Larrea tridentata and other plants. The mol­ecule has a noncrystallographic inversion center situated at the midpoint of the central C—C bond, generating the meso stereoisomer. The central C—C—C—C alkyl chain displays an all-trans conformation, allowing an almost parallel arrangement of the benzene rings, which make a dihedral angle of 5.0 (3)°. Both hydr­oxy groups form weak O—H⋯O—H chains of hydrogen bonds along [100]. The resulting supra­molecular structure is an undulating plane parallel to (010)

A new RP-HPLC method as an auxiliary tool for optimization of sample preparation procedures for tracing of PPCPs of different hydrophilicities

Recently, pharmaceutical and personal care products (PPCPs) have received considerable attention because of their increasing use. Analysis of PPCPs presents a significant analytical challenge, with high-performance liquid chromatography (HPLC) in reversed-phase mode, as the most widely used analytical technique. To facilitate the optimization of the procedures that are applied in the early stages of sample preparation, a simple and fast HPLC method is proposed in this work for the separation of some PPCPs with a wide range of hydrophilicity. Two columns were evaluated (Atlantis dC18 and Discovery HS F5); as for mobile phases: a formate buffer (40 mmol L-1, pH 4) and methanol were tested in a gradient mode. The fluorinated column allowed better separation in a shorter time and better resolution for all analytes (Rs >1). The proposed method delivered good performance for the tracing of PPCPs and is a suitable alternative to traditional C18-based HPLC methods

CUANTIFICACIÓN DE T 514 (PEROXISOMICINA A1) EN DOS PLANTAS DEL GÉNERO KARWINSKIA

Quantification of T 514 (peroxisomicineA1), a dimeric hydroxyanthracenone with potential antineoplasic effect is describedwhich was accomplished in two species ofgenus Karwinskia, collected in differenlocations of Mexico. The best source forthe extraction of this compound proved tobe Karwinskia parvifolia. This species wascollected in Sinaloa and Sonora; the resultsshowed a high amount of peroxisomicineA1, scarce stational variation and thepresence of a few number of secondarymetabolites which could interfere with theprocedure of extraction and purification.Se describe la cuantifiación de T 514 operoxisomicina A1, posible agenteantineoplásico, en dos plantas del géneroKarwinskia, obtenidas en distintas regiones de México. La mejor fuente de extracción de este compuesto resultó ser K.parvifolia, proveniente de Sinaloa y Sonora, por su alto contenido del compuesto encuestión, su escasa variabilidad estacionaly la presencia de pocas sustanciasinterferentes que pudieran complicar elprocedimiento de extracción y purificación

Unintentional pediatric injuries in Sao Paulo. How often is it severe?

Purpose: To evaluate severity and built a pilot of a national databank about pediatric trauma and to determine its severity. Methods: Prospective study of unintentional pediatric trauma in five hospitals in the city of Sao Paulo, Brazil. Results: 916 patients in 4 months. 61.5% of traumatized children were male, average 6.5 years. 48. 4% were falls. Most families had an average monthly income less than three minimum wages. 42% of accidents occurred at home. 18.9% of children were alone. 59,8% of parents thought it could be prevented. 26.5% of children had previous accidents. GCS was severe: 5 patients, moderate: 8 patients. 21 patients were intubated (2.4%), RTS <7 in 10.2%, PTS<8 in 3.6%. 8.5% patients were considered severe, which was related to falls (p= 0.001)sports (p= 0.045)pedestrian (p= 0.006)child education (p= 0.015) and cared by male (p= 0.007). Conclusions: Severity occurred in 8.5% and was associated to falls, sports, traffic, child education, and cared by male. Simple preventive measures could have prevented most of the accidents. The tested tool for details was successful and can be used throughout the country.Univ Fed Sao Paulo UNIFESP, Dept Surg, Sao Paulo, SP, BrazilOrg Nao Govt ONG Crianca Segura, Sao Paulo, SP, BrazilONG Crianca Segura, Sao Paulo, SP, BrazilSoc Brasileira Pediat, Dept Childhood Safety, Sao Paulo, SP, BrazilAssociacao Brasileira Defesa Consumidor PROTESTE, Sao Paulo, SP, BrazilTeaching & Simulat Ctr HCor CETES HCor, Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Dept Surg, Rua Coronel Lisboa 687, BR-04020041 Sao Paulo, SP, BrazilUniv Fed Para UFPA, Belem, Para, BrazilUniv Fed Sao Paulo UNIFESP, Operat Tech & Expt Surg, Dept Surg, Sao Paulo, SP, BrazilUniv Fed Sao Paulo UNIFESP, Dept Surg, Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Dept Surg, Rua Coronel Lisboa 687, BR-04020041 Sao Paulo, SP, BrazilUniv Fed Sao Paulo UNIFESP, Operat Tech & Expt Surg, Dept Surg, Sao Paulo, SP, BrazilWeb of Scienc