35 resultados para Cutis laxa


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Autosomal recessive cutis laxa type I (ARCL type I) is characterized by generalized cutis laxa with pulmonary emphysema and/or vascular complications. Rarely, mutations can be identified in FBLN4 or FBLN5. Recently, LTBP4 mutations have been implicated in a similar phenotype. Studying FBLN4, FBLN5, and LTBP4 in 12 families with ARCL type I, we found bi-allelic FBLN5 mutations in two probands, whereas nine probands harbored biallelic mutations in LTBP4. FBLN5 and LTBP4 mutations cause a very similar phenotype associated with severe pulmonary emphysema, in the absence of vascular tortuosity or aneurysms. Gastrointestinal and genitourinary tract involvement seems to be more severe in patients with LTBP4 mutations. Functional studies showed that most premature termination mutations in LTBP4 result in severely reduced mRNA and protein levels. This correlated with increased transforming growth factor-beta (TGFβ) activity. However, one mutation, c.4127dupC, escaped nonsense-mediated decay. The corresponding mutant protein (p.Arg1377Alafs(*) 27) showed reduced colocalization with fibronectin, leading to an abnormal morphology of microfibrils in fibroblast cultures, while retaining normal TGFβ activity. We conclude that LTBP4 mutations cause disease through both loss of function and gain of function mechanisms.

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Primary vesicoureteral reflux (VUR) is a common pediatric condition due to a developmental defect in the ureterovesical junction. The prevalence of VUR among individuals with connective tissue disorders, as well as the importance of the ureter and bladder wall musculature for the anti-reflux mechanism, suggest that defects in the extracellular matrix (ECM) within the ureterovesical junction may result in VUR. This review will discuss the function of the smooth muscle and its supporting ECM microenvironment with respect to VUR, and explore the association of VUR with mutations in ECM-related genes.

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Brown rot caused by Monilinia laxa and Monilinia fructigena is considered one of the most important diseases affecting Prunus species. Although some losses can result from the rotten fruits in the orchard, most of the damage is caused to fruits during the post-harvest phase. Several studies reported that brown rot incidence during fruit development highly varies; it was found that at a period corresponding to the the pit hardening stage, fruit susceptibility drastically decreases, to be quickly restored afterwards. However the molecular basis of this phenomenon is still not well understood. Furthermore, no difference in the rot incidence was found between wound and un-wound fruits, suggesting that resistance associated more to a specifc biochemical response of the fruit, rather than to a higher mechanical resistance. So far, the interaction Monilinia-peach was analyzed through chemical approaches. In this study, a bio-molecular approach was undertaken in order to reveal alteration in gene expression associated to the variation of susceptibility. In this thesis three different methods for gene expression analysis were used to analyze the alterations in gene expression occurring in peach fruits during the pit hardening stage, in a period encompassing the temporary change in Monilinia susceptibility: real time PCR, microarray and cDNA AFLP techniques. In 2005, peach fruits (cv.K2) were weekly harvested during a 19-week long-period, starting from the fourth week after full bloom, until full maturity. At each sampling time, three replicates of 5 fruits each were dipped in the M.laxa conidial suspension or in distilled water, as negative control. The fruits were maintained at room temperature for 3 hours; afterwards, they were peeled with a scalpel; the peel was immediately frozen in liquid nitrogen and transferred to -80 °C until use. The degree of susceptibility of peach fruit to the pathogen was determined on 3 replicates of 20 fruits each, as percentage of infected fruits, after one week at 20 °C. Real time PCR analysis was performed to study the variation in expression of those genes encoding for the enzymes of the phenylpropanoid pathway (phenylalanine ammonia lyase (PAL), chalcone synthase (CHS), cinnamate 4-hydroxylase (C4H), leucoanthocyanidine reductase (LAR), hydroxycinnamoyl CoA quinate hydroxycinnamoyl transferase (HQT) and of the jasmonate pathway, such as lipoxygenase (LOX), both involved in the production of important defense compounds. Alteration in gene expression was monitored on fruit samples of a period encompassing the pit hardening stage and the corresponding temporary resistance to M.laxa infections, weekly, from the 6thto the 12th week after full bloom (AFB) inoculated with M. laxa or mock-inoculated. The data suggest a critical change in the expression level of the phenylpropanoid pathway from the 7th to the 8th week AFB; such change could be directly physiologically associated to the peach growth and it could indirectly determine the decrease of susceptibility of peach fruit to Monilinia rot during the subsequent weeks. To investigate on the transcriptome variation underneath the temporary loss of susceptibility of peach fruits to Monilinia rot, the microarray and the cDNA AFLP techniques were used. The samples harvested on the 8th week AFB (named S, for susceptible ones) and on the 12th week AFB (named R, for resistant ones) were compared, both inoculated or mock-inoculated. The microarray experiments were carried out at the University of Padua (Dept. of Environmental Agronomy and Crop Science), using the μPEACH1.0 microarray together with the suited protocols. The analysis showed that 30 genes (corresponding to the 0.6% of the total sequences (4806) contained in the μPeach1.0 microarray) were found up-regulated and 31 ( 0.6%) down regulated in RH vs. SH fruits. On the other hand, 20 genes (0.4%) were shown to be up-regulated and 13 (0.3%) down-regulated in the RI vs. SI fruit. No genes were found differentially expressed in the mock-inoculated resistant fruits (RH) vs. the inoculated resistant ones (RI). Among the up-regulated genes an ATP sulfurylase, an heat shock protein 70, the major allergen Pru P1, an harpin inducing protein and S-adenosylmethionine decarboxylase were found, conversely among the down-regulated ones, cinnamyl alcohol dehydrogenase, an histidine- containing phosphotransfer protein and the ferritin were found. The microarray experimental results and the data indirectly derived, were tested by Real Time PCR analysis. cDNA AFLP analysis was also performed on the same samples. 339 transcript derived fragments considered significant for Monilinia resistance, were selected, sequenced and classified. Genes potentially involved in cell rescue and defence were well represented (8%); several genes (12.1%) involved in the protein folding, post-transductional modification and genes (9.2%) involved in cellular transport were also found. A further 10.3% of genes were classified as involved in the metabolism of aminoacid, carbohydrate and fatty acid. On the other hand, genes involved in the protein synthesis (5.7%) and in signal transduction and communication (5.7%) were found. Among the most interesting genes found differentially expressed between susceptible and resistant fruits, genes encoding for pathogenesis related (PR) proteins were found. To investigate on the association of Monilinia resistance and PR biological function, the major allergen Pru P1 (GenBank accession AM493970) and its isoform (here named Pru P2), were expressed in heterologous system and in vitro assayed for their anti-microbial activity. The ribonuclease activity of the recombinant Pru P1 and Pru P2 proteins was assayed against peach total RNA. As the other PR10 proteins, they showed a ribonucleolytic activity, that could be important to contrast pathogen penetration. Moreover Pru P1 and Pru P2 recombinant proteins were checked for direct antimicrobial activity. No inhibitory effect of Pru P1 or Pru P2 was detected against the selected fungi.

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Calcinosis cutis is a rare condition characterized by the deposition of insoluble calcium salts in the skin and subcutaneous tissue. Dystrophic calcinosis cutis appears as a result of local tissue damage or abnormalities, such as alterations in extra-cellular matrix proteins or subcutaneous tissue with normal calcium and phosphate serum levels. It has been rarely described as a late complication of burns. Latency periods of 15-54 years have been reported. We describe the case of a 57-year-old man with dystrophic calcinosis cutis in a burn scar, which developed 42 years after the skin injury. The condition was successfully treated with surgical excision.

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Subsampling is a common method for estimating the abundance of species in trawl catches. However, the accuracy of subsampling in representing the total catch has not been assessed. To estimate one possible source of bias due to subsampling, we tested whether the position on trawler sorting trays from which subsamples were taken affected their ability to represent species in catches. This was done by sorting catches into 10 kg subsamples and comparing subsamples taken from different positions on the sorting tray. Comparisons were made after species were grouped into three categories of abundance, either 'rare', 'common' or 'abundant'. A generalised linear model analysis showed that taking subsamples from different positions on the sorting tray had no major effect on estimating the total numbers or weights of fish or invertebrates, or the total number of fish or invertebrate taxa, recorded in each position. Some individual taxa showed differences between positions on the sorting tray (11.5% of taxa ina three-position design; 25% in a five-position design). But consistent and meaningful patterns in the position of these taxa on the sorting tray could only be seen for the pony fish Leiognathus moretoniensis and the saucer scallop Amusium pleuronectes. Because most bycatch laxa are well mixed throughout the catch, subsamples can be taken from any position on trawler sorting trays without introducing bias.

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嵩草属隶属于莎草科苔草亚科苔草族,主要分布于北半球温带地区,少数种类为环北极分布,有一种产于泰国清迈,一种产于苏门达腊岛北部高山。本‘文在形态学、微形态学、解剖学和胚胎学研究的基础上,对嵩草属植物进行了全面的分类学修订,根据属内各类群之间的系统演化关系建立了一个新的属下分类系统,确认了世界范围内53种3亚种嵩草属植物,并做出5个种上等级的新组合,描述了一个新亚组。 作者研究了国内外14家标本馆(室)的3000多份腊叶标本并进行多次野外的实地观察,对嵩草属植物的形态学性状进行了详细的比较和分析,评价了它们的系统学价值及其演化趋势。在嵩草属中,花序是由小穗排列成的圆锥花序或穗状花序,花序各部分的形态性状是种及种上等级分类的基础;花序的演化趋势是由圆锥花序到穗状花序,小穗是从由数朵雄花与1朵雌花组成简化到由1朵雌花组成。但是,花序和小穗由复杂到简单的进化在嵩草属中平行地发生于不同的类群中。先出叶的性状状态是分种的主要特征之一,通常认为边缘开裂的先出叶是原始的,边缘合生而为囊状的先出叶是进化的。同样,先出叶由开裂到合生的进化也是多次发生的。此外,根状茎、秆、叶鞘、叶片、柱头及小坚果等的性状状态对于种及种上等级的分类都具有重要的意义。 应用扫描电子显微镜对38种(或亚种)嵩草属植物的小坚果表面进行了观察,证明小坚果纹饰在种及种上等级的分类中具有重要的参考价值,并能揭示种及种下等级的亲缘关系。例如,分布于喜马拉雅东部至横断山地区的3种植物,K.clarkeana、K.curvata和K.fragilis外部形态非常相似,难于区分,而其小坚果的微形态特征却可以提供3种之间关系的证据。K.clarkeana与K.fragilis果实表面的特征完全一致,且与其它植物有显著区别,应为同种植物;K.curvata与它们明显不同,也与其它种有较大差异,应为独立的种。K.gramini folia,K.cercostach ys和K. nepalensis果实表面纹饰具有一些共同的特征,说明它们之间的亲缘关系较近。K.filicina和K.duthiei也存在同样的情形。 通过对秆和叶片的横切面和表皮的解剖学观察比较,发现嵩草属植物秆的横切面表现出由三角形到圆形的一系列变化。秆的横切面明显地分两个区域,中部的髓由较大而无色的细胞组成,其中心常碎裂形成大的气腔;外围的绿色部分,由绿色组织及分布其中的气腔和外韧维管束及与其相伴的厚壁组织组成。秆的表皮与叶片下表皮非常相象。叶片横切面的外形为V形、新月形或半圆形。V形的叶片具有明显发育的中脉并且在远轴面凸起,形成脊;新月形和半圆形的叶片中脉发育不明显,也无脊。叶片的表皮细胞均为长方形,垂周壁波纹状;平列型的气孔器纵向成行排列,多局限于下表皮;上表皮近边缘及脉附近的细胞常常在细胞的一端形成乳突。秆和叶片横切面的形态对于分种及种上等级的划分具有参考价值。 胚胎学研究表明小孢子、胚囊和胚的发育与莎草科其它类群一致。花粉为假单体花粉( pseudomonad),成熟花粉三核。胚珠倒生,厚珠心,双层珠被,珠孑L由内珠被形成。胚囊的发育为蓼型,原胚的发育为柳叶菜型灯芯草变型。首次观察到,在大孢子四分体时期,合点端和珠孔端两个大孢子细胞开始时体积都增大,而中部两个很快退化,稍后珠孔端一个也退化,合点端一个为功能大孢子,发育成为胚囊。根据胚胎学证据,不支持将嵩草属与苔草族一起另立为嵩草科。 嵩草属中较原始的一个亚属subg. Compositae主要分布于西喜马拉雅至横断山地区,还有一种见于泰国,一种产于苏门达腊,而后2种植物还具有一些最原始的形态性状。结合地史的变化推测,嵩草属可能在第三纪早期起源于古地中海的东部和北部。 根据形态学和解剖学性状的分析表明,许多性状在嵩草属中是平行演化的,如花序和小穗由复杂到简单、秆由圆柱形到三棱形、叶片横切面由V形到半圆形等。该属的属下分类应该追溯这些平行的演化线,而不能像以前的分类那样,将它们横向地划分为几个组或亚属。作者认为嵩草属有3个大的进化分支,据此将其划分为3个亚属。Subg. Compositae,12种,是较原始的一个分支。叶近基生,叶片扁平;花序多疏松圆锥状,少穗状,苞片多为叶状;小穗两性到单性,先出叶多为囊状,少边缘分离,退化小穗轴明显、扁平、较长。Subg. Blysmocarex,仅2种,是较早分化而相对隔离的一个分支。根状茎匍匐状;花序由圆锥状到穗状,小穗两性或单性;柱头2。Subg. Kobresia,种类最多。叶片扁平或内卷;秆三棱形到圆柱形;花序紧密,复杂到简单,苞片不为叶状;小穗两性或单性,先出叶由开裂到合生,退化小穗轴较小而不显著。根据该亚属呈现出的不同的性状演化系列,可以分为3个组。Sect. Kobresia花序圆锥状至穗状,小穗多为两性,少为单性,先出叶边缘分离。含3个亚组:subsect. Kobresia,8种2亚种.植株纤细,秆与叶均为丝状;subsect. Royleanae,8种l亚种,植株较粗壮,叶片扁平或对折;subsect. Sibiri-cae,4种,秆较粗,叶片内卷。Sect. Psmmostachys,仅2种,小穗两性,先出叶完全合生为囊状。Sect.Hemicarex花序一般为穗状,稀圆锥状,小穗多为单性,少两性。分为四个亚组:subsect. Forexeta,6种,叶片内卷或对折,先出叶线形,边缘分离或合生;subsect. Chlorostachys,3种,叶片扁平,小穗两性;subsect. Holmia,4种,叶片扁平,小穗单性;subsect.Utriculatae,5种,叶片丝状,先出叶完全合生为囊状,不为线形。嵩草属的属下分类纲要如下: Subgenus 1. Compositae (Clarke) Kukkonen Type: K. laxa Nees. Subgenus 2. Blysmocarex (Ivanova) S. R. Zhang Type: K. macrantha Boeck. Subgenus 3. Kobresia Section 1. Kobresia Subsection 1. Kobresia Type: K. simpliciuscula (Wahl. ) Mack. Subsection 2. Royleanae (Ivanova) S. R. Zhang Type: K. royleana (Nees) Boeck. Subsection 3. Sibiricae (Ivanova) Egorova Type: K. sibirica (Turcz. ex Ledeb. ) Boeck. Section 2. Psmmostachys Ivanova Type: K. robusta Maxim. Section 3. Hemicarex (Bentham) Clarke Subsection 4. Forexeta (Raffin. ) S. R. Zhang Type: K. cercostachys (Franch. ) C. B. Clarke. Subsection 5. Chlorostachys (Ivanova) S. R. Zhang Type: K. duthiei C B. Clarke. Subsection 6. Holmia (Boern. ) S. R. Zhang Type: K. esenbeckii (Kunth) Noltie. Subsection 7. Utriculatae S. R. Zhang Type: K. prainii Kukenthal.

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Durante los últimos 35 años las drogas ilegales han constituido un factor significativo en el drama social colombiano. Hoy día es común atribuir a éstas la causalidad de muchos problemas del país y se han elaborado algunas explicaciones del desarrollo de dicha "industria" en Colombia, de las cuales se derivan recomendaciones de política, tanto las implementadas por los gobiernos como las recomendadas por los críticos. El Centro de Estudios y Observatorio de Drogas y Delito (Ceodd),(...) de la Facultad de Economía de la Universidad del Rosario, ha encontrado que las explicaciones más comunes pueden clasificarse en tres grupos. El primero, incluye afirmaciones simples que atribuyen el desarrollo de las drogas ilegales a la pobreza, a la desigualdad, a las crisis económicas, a la corrupción o a la localización de Colombia a mitad de camino entre las plantaciones de coca de Bolivia y Perú con Estados Unidos. (...) En segundo lugar, se encuentran las razones basadas en modelos de criminalidad común, también llamados policivos, en los cuales las leyes surgen de procesos legitimados por la sociedad y quienes las violan son considerados personas con comportamientos desviados, que deben corregirse por medio de sanciones o restricciones. Siguiendo este enfoque, las políticas hacia las drogas tienen que ser represivas. En tercer lugar, están las respuestas basadas en la elevada rentabilidad de las drogas, generada por su ilegalidad, y por la existencia de una gran demanda internacional: por ejemplo, un kilo de cocaína en Colombia puede costar unos US$1.500 y cuando llega a los Estados Unidos se paga entre US$15.000 y US$18.000. Según estimaciones de las Naciones Unidas, en los últimos años la demanda mundial de cocaína ha estado alrededor de 800 toneladas. Este enfoque justifica la producción ilegal y quienes lo apoyan creen que el país produce drogas como resultado de un ‘choque externo’. Los que comulgan con esta posición consideran que Colombia, en los años sesenta, era una nación típica en términos de criminalidad, afectada por el surgimiento de una gran demanda externa de drogas que estimuló la producción de éstas. Este desarrollo constituye la causa principal de los graves problemas que enfrenta actualmente el país. Según esta explicación, la razón por la cual el país produce drogas radica en el exterior y la única solución es la legalización para acabar el ‘choque externo’. Desafortunadamente, quienes apoyan este modelo no explican por qué ese ‘choque externo’ afectó de manera tan grave a Colombia y no a otros países como Ecuador, Perú y Bolivia, donde no se desarrollaron grandes carteles de traficantes, o en Malasia, Indonesia y Taiwán, que en el pasado fueron grandes exportadores de coca. Sin embargo, la evidencia empírica encontrada por el Ceodd contradice los argumentos anteriores, pues ninguno explica por qué la producción y el tráfico de drogas ilegales están concentrados en pocos países. En el caso de la teoría policiva, la concentración se explicaría solamente si por razones genéticas una población fuera más proclive al crimen. Respecto a la producción justificada por la rentabilidad, ésta se explicaría si todos los países que pudieran producir coca, amapola, cocaína y heroína lo estuvieran haciendo. La coca puede crecer en unos 30 países, la amapola en 120 y la cocaína y la heroína se pueden refinar en cualquier parte del mundo. Por consiguiente, si la rentabilidad determinara la producción, Colombia sería sólo uno entre los muchos productores. De la misma forma, otras explicaciones como la pobreza, las crisis, la desigualdad y la corrupción fallan porque dichos problemas son endémicos en muchas sociedades que no producen o trafican drogas. La localización geográfica del país, por su parte, no explica por qué en Colombia surgieron las grandes organizaciones criminales. Además, cuando la diferencia entre los precios de exportación e importación es tan grande, como en el caso de la cocaína y de la heroína, los costos de transporte y la distancia son problemas menores. En ese caso lo que importa es reducir el riesgo y no la distancia. Ahora bien, si no hubiera demanda de drogas tampoco habría oferta y sin oferta no habría demanda. La teoría económica enseña que la demanda y la oferta son como las dos hojas de una tijera: ambas son necesarias para que haya un mercado. Para el Ceodd, estas afirmaciones son ciertas pero triviales e incompletas. La rentabilidad de las drogas es una condición necesaria, pero no suficiente para que en un país se cultive coca y se refine cocaína. Entonces, lo que se debe averiguar es por qué una condición necesaria, en el caso colombiano, se vuelve suficiente. Es claro que la gran demanda internacional es ilegal y que cuando un producto fácil de fabricar, que no requiere grandes destrezas o capital -como la cocaína o la heroína- es declarado ilegal a nivel mundial, su producción y tráfico tenderá a concentrarse en los países donde el imperio de la ley sea más débil y la sociedad más laxa frente a la ilegalidad. Es cierto que si la cocaína no fuera rentable no se produciría, pero Colombia no concentra la producción de cocaína porque sea rentable sino porque es ilegal, advierte el director del Ceodd, Francisco E. Thoumi.

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Introducción: Los resultados de la remoción de tatuajes con láser de sesión a sesión según los parámetros utilizados son limitados en la literatura. Objetivo: Evaluar los cambios en el aclaramiento de tatuajes y factores asociados posterior a una sesión con láser y los efectos adversos. Materiales y Métodos: Estudio longitudinal retrospectivo de antes y después de 1 sesión de con láser para remoción de tatuajes, donde se determinaron parámetros del tratamiento, aclaramiento y efectos adversos. Resultados: Se evaluaron 35 pacientes para un total de 98 sesiones, fototipo de piel II y IV. Equipos utilizados laser Q-Switch Nd Yag 1064 (83.3%), láser Q-Switch Nd YAG 532(11.3%) y laser Q-Switch Rubí (4.1%). El aclaramiento posterior a la sesión de láser fue evaluado por dos evaluadores independientes, mostrando concordancia significativa (Kappa de 0.615, p<0.001), con aclaración en un 96% de los tatuajes después de la sesión de láser. (p< 0.001). Se encontraron cambios significativos entre la densidad de energía aplicada y las categorías de aclaramiento de la escala de 0 a 3, siendo a mayor densidad mayor el nivel de aclaramiento (p= 0.05). No se encontró asociación significativa entre el número de pases y el aclaramiento del tatuaje. Los efectos adversos fueron del 5.4%. Cicatriz 2%, hiperpigmentación 2% y hipopigmentación 1%. Conclusión: Posterior a una sesión de remoción de tatuajes con láser Q-Switch hay un aclaramiento significativo en un 96% asociado con la densidad de energía, a mayor densidad de energía mayor el nivel de aclaramiento y no al número de pases realizados.

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OBJETIVO: Avaliar a prevalência de lesões cutâneas actínicas em portadores de carcinoma basocelular do segmento cefálico. MÉTODOS: Foi conduzido estudo tipo caso-controle. Os casos, constituídos por pacientes com carcinoma basocelular sólido, primário, menor que dois centímetros, no segmento cefálico; e controles, por pacientes com outras dermatoses. Foram analisadas variáveis constitucionais, comportamentais e lesões actínicas. RESULTADOS: Avaliaram-se 120 casos e 360 controles. Mílio facial (OR = 2,3), leucodermia puntacta de membros superiores (OR = 2,9) e cutis romboidalis nuchae (OR = 1,8) associaram-se à neoplasia independentemente das demais variáveis, sugerindo um fenótipo de risco. Houve ainda associação com fenótipos claros, genética familiar e exposição solar cumulativa. Queimadura solar, tabagismo e alcoolismo não foram identificados como fatores de risco. O uso de fotoprotetores não evidenciou proteção; porém, o grupo controle era composto por pacientes dermatológicos, aos quais são indicados fotoprotetores regularmente. CONCLUSÃO: Lesões actínicas foram mais prevalentes em portadores de carcinoma basocelular sólido do segmento cefálico que em controles, especialmente mílio, cutis romboidalis nuchae e leucodermia puntacta, independentemente dos demais fatores de risco conhecidos.

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Hereditary equine regional dermal asthenia belongs to a group of inherited, congenital connective tissue dysplasias usually described as hyperelastosis cutis, cutaneous asthenia, dermatosparaxis, or Ehlers-Danlos-like syndrome. This report presents the clinical and histological features of three related Quarter horses affected with regional dermal asthenia. These horses had bilateral asymmetric lesions of the trunk and lumbar regions, where the skin was hyperextensible. Handling of the skin elicited a painful response and superficial trauma led to skin wounds. The skin was thinner than normal in the affected areas, with thickened borders and harder fibrotic masses (pseudotumours). The histopathological findings included thinner and smaller collagen fibrils, and a loose arrangement of collagen fibres in the middle, adventitial and deep dermis. Masson's trichrome and Calleja stains did not reveal any abnormality of collagen and elastic fibres. Electron microscopy showed no abnormalities. As in human patients, pseudotumour histopathological findings included fibroplasia and neovascularization. The pedigree chart of these animals supports an autosomal recessive type of inheritance, which has been suggested by other studies. This is the first report of this disease in Brazil. Its clinical and histological features resemble those described in horses affected with this condition in the United States.

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A new species of Pelexia Poit. ex Until. (Orchidaceae, Spiranthinae) occurring in central Sao Paulo, southeastern Brazil, is described and illustrated as P. vinosa A. W. C. Ferreira, M. I. S. Lima & Pansarin. Pelexia vinosa is recognized by its leaves that are present at flowering and its dark purple leaf blades with reddish margins. Inflorescences are sparsely pubescent and reddish. The red sepals contrast with the white hyaline petals and labellum. The species is notable for its spurlike nectary that is parallel and adnate to the ovary. The new species is morphologically similar to P. laxa (Poepp. & Endl.) Lindl. In addition, the need to preserve native areas of the interior of Sao Paulo State (habitat of P. vinosa) is discussed.

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Tegumentary leishmaniases are caused by approximately 15 species of protozoa of the genus Leishmania. They prevail in tropical and subtropical areas of the Old and New World but human mobility also makes them a medical problem in nonendemic areas. Clinical manifestations may comprise cutaneous and mucocutaneous forms that may be localized, disseminated, or diffuse in distribution and may differ in Old and New World leishmaniases. Diagnosis and treatment vary according to the clinical manifestations, geographic area, and Leishmania species involved. This article highlights the diversity and complexity of tegumentary leishmaniases, which are worsened by human immunodeficiency virus/Leishmania coinfection.

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Background: Sugarcane is one of the most important crops in Brazil, mainly because of its use in biofuel production. Recent studies have sought to determine the role of sugarcane endophytic microbial diversity in microorganism-plant interactions, and their biotechnological potential. Epicoccum nigrum is an important sugarcane endophytic fungus that has been associated with the biological control of phytopathogens, and the production of secondary metabolites. In spite of several studies carried out to define the better conditions to use E. nigrum in different crops, little is known about the establishment of an endophytic interaction, and its potential effects on plant physiology. Methodology/Principal Findings: We report an approach based on inoculation followed by re-isolation, molecular monitoring, microscopic analysis, plant growth responses to fungal colonization, and antimicrobial activity tests to study the basic aspects of the E. nigrum endophytic interaction with sugarcane, and the effects of colonization on plant physiology. The results indicate that E. nigrum was capable of increasing the root system biomass and producing compounds that inhibit the in vitro growth of sugarcane pathogens Fusarium verticillioides, Colletotrichum falcatum, Ceratocystis paradoxa, and Xanthomomas albilineans. In addition, E. nigrum preferentially colonizes the sugarcane surface and, occasionally, the endophytic environment. Conclusions/Significance: Our work demonstrates that E. nigrum has great potential for sugarcane crop application because it is capable of increasing the root system biomass and controlling pathogens. The study of the basic aspects of the interaction of E. nigrum with sugarcane demonstrated the facultative endophytism of E. nigrum and its preference for the phylloplane environment, which should be considered in future studies of biocontrol using this species. In addition, this work contributes to the knowledge of the interaction of this ubiquitous endophyte with the host plant, and also to a better use of microbial endophytes in agriculture.

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Antimicrobial peptides (AMPs) are an important component of the innate immune system of the plants. Plant defensins are a large family of antimicrobial peptides with several interesting features, such as small dimension, high stability and broad spectrum of action. The discovery of new molecules and the study of their mechanism of action allow to consider them attractive for biotechnological applications. In this PhD thesis a defensin from Prunus persica (PpDFN1) and four novel DEFensin Like (DEFL) peptides from Vitis vinifera have been studied. In order to characterize the antimicrobial activity of these molecules, the recombinant mature peptides have been expressed in Escherichia coli and purified to homogeneity by chromatography techniques. PpDFN1 is able to inhibit the growth of B. cinerea, P. expansum and M. laxa with different intensity. The recombinant peptide is capable of membrane permeabilization as demonstrated by SYTOX green fluorescence uptake in treated mycelia. Its interaction with membranes containing sphingolipid species has been shown by artificial lipid monolayers. Furthermore, PpDFN1 displays stronger interaction with monolayers composed by lipids extracted from sensitive fungi with the highest interaction against P. expansum, the most sensitive fungi to PpDFN1 action. DEFL 13, a defensin from grapevine, resulted the strongest antibotrytis peptides. It is electrostatically attracted to the fungal membranes as shown by the antagonist effect of the cations and is able to membrane permeabilization in B. cinerea hyphae. DEFL 13 is internalized in fungal cells and leads to fungal death by activation of some signaling pathways as demonstrated by screening of a mutant collection of B. cinerea