34 resultados para FML


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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The FML antigen of Leishmania donovani, in combination with either Riedel de Haen (R), QuilA, QS21 saponins, IL12 or BCG, was used in vaccination of an outbred murine model against visceral leishmaniasis (VL). Significant and specific increases in anti-FML IgG and IgM responses were detected for all adjuvants, and in anti-FML IgG1, IgG2a and IgG2b and delayed type of hypersensitivity to L. donovani lysate (DTH), only for all saponins and IL12. The QS21-FML and QuilA-FML groups achieved the highest IgG2a response. QuilA-FML developed the strongest DTH and QS21-FML animals showed the highest serum IFN-gamma concentrations. The reduction of parasitic load in the liver in response to each FML-vaccine formulation was: 52% (P < 0.025) for BCG-FML, 73% (P < 0.005) for R-FML, 93% (P < 0.005) for QuilA-FML and 79.2% (P < 0.025) for QS21-FML treated animals, respectively. Protection was specific for R-FML and QS21-FML while the QuilA saponin treatment itself induced 69% of LDU reduction. The FML-saponin vaccines promote significant, specific and strong protective effects against murine visceral leishmaniasis. BCG-FML induced minor and non-specific protection while IL 12-FML, although enhancing the specific antibody and IDR response, failed to reduce the parasitic load of infected animals. (C) 2002 Elsevier B.V. Ltd. All rights reserved.

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The fucose mannose ligand (Leishmania donovani FML)-saponin vaccine has earlier shown its immunoprophylactic potential against visceral leishmaniasis in the CB hamster (87.7% of parasite load reduction), Balb/c (84.4%) and Swiss albino mouse (85-93%) models. In this investigation its specific immunotherapeutic efficacy against L. donovani infection in Balb/c mice was studied. The effects of vaccine treatment on the Immoral response, delayed type of hypersensitivity to promastigote lysate (DTH), cytokine levels in sera and reduction of the liver parasitic load of L. donovani infected mice, were examined. The types and subtypes of anti-FML antibodies increased significantly in the vaccinees over the saline and saponin controls. As expected for a saponin vaccine, the highest ratios were found in relation to IgG1, IgG2a and IgG2b (4.4, 5 and 2.5, respectively). The DTH response and the in vitro ganglion cell proliferative response against FML antigen were also significantly higher than controls (P < 0.005). Concomitantly, an impressive and specific decrease of liver parasitic burden was detected only in vaccine-treated animals (94.7%). Our results indicate that the therapeutic FML-vaccine has a potent effect on modulation of the murine infection leading to the reduction of parasitic load and signs of disease, being a new potential tool in the therapy and control of visceral leishmaniasis. (C) 2003 Elsevier Ltd. All rights reserved.

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"September 1989."

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玉米幼苗经外源脱落酸(ABA)处理后,其生长与光合作用,如株高、干物质积累、净光合速率(Pn)、光合作用的量子效率(фC02)和羧化效率(CE),以及光系统II (PSII)实际光化学效率(фPSII)等受到抑制,且该抑制程度与处理ABA的浓度呈相关性。PSII最大光化学活性(Fv/Fm)变化表明,以10和25μmol L-I ABA处理玉米幼苗7天,可明显提高其抗光抑制能力,而50μmol L-1ABA处理的玉米幼苗在相同条件下的抗光抑制能力下降。进一步以25μmol L-lABA处理玉米幼苗来研究,结果表明ABA处理可减缓强光下玉米叶片Pn、CE、фPS II和叶片吸收光能光化学猝灭(qP)的下降,同时增强叶片吸收光能的非光化学猝灭(NPQ)。另外,叶绿素荧光非光化学猝灭的中间组分(qm)增强,光抑制后Fv/Fm的恢复能力提高,这表明ABA处理高提高了强光下玉米幼苗的光系统状态转换能力和Psn循环修复作用。除此之外,ABA处理后玉米幼苗的叶黄素循环类色素,如紫黄质(V)、环氧玉米黄质(A)和玉米黄质(Z)的含量增加,叶黄素循环库(V+A+Z)增大,说明依赖于叶黄素循环的热耗散在ABA处理玉米幼苗中得到加强。另外,ABA处理幼苗在强光下保持较高фPsII/Pn活性,以及叶片抗氧化酶活性提高,如超氧化物歧化酶(SOD)、抗坏血酸过氧化物酶(APX)、单脱氢抗坏血酸还原酶(DHAR)和谷胱甘肽还原酶(GR),抗氧化物含量增加,如抗坏血酸(AsA)、脱氢抗坏血酸(DHAsA)、还原型谷胱甘肽(GSH)和氧化型谷胱甘肽(GSSH),这说明ABA诱导Mehler-peroxidase反应的增强在提高玉米幼苗抗光抑制能力中也发挥重要作用。 玉米叶片光系统I和光系统II在相同强度(300μmolm-2 S-l)的红光(655nm)和远红光(700-770 nm)共同照射下,光系统I(PSI)和光系统II(PSII)吸收光能基本平衡,叶片光合作用处于状态1,此时Psn保持较高的光适应下最大荧光( Fml)。关闭远红光,使叶片只处在红光照射下,则会引起光下PSII最大荧光( Frri2)的降低。关闭远红光约20nun后,光下下降的Psn最大荧光基本达到稳定,叶片光合作用处于状态2。这种在状态l向状态2的转换过程中所发生的PSII最大荧光下降不受DTT(叶黄素循环抑制剂)的影响,且整个过程中PsII最大光化学效率( Fv/Fm)保持不变,而光下PSII初始荧光(F0')在前20min内迅速降低。另外,在PSII吸收的红光照射下,玉米叶片吸收光向PSII分配的量(B)不断减少,与此同时,吸收光能向PSI分配的量(a)不断增多。ABA预处理玉米幼苗7天,可进一步加强红光下PSII最大荧光(Fm2)的降低,使荧光参数Fm1/Fm2—1增大,而使β/α-1降低。另外,ABA处理较对照幼苗在红光下呈现更高的荧光非光化学猝灭中间组分(qm)。在引入叶绿体蛋白激酶抑制剂NEM的情况下,ABA处理与对照玉米叶片在红光下所表现的qm差异则消失。从状态1向状态2的转换过程中,ABA处理引起玉米叶片77K低温荧光F684/F732的下降幅度显著加大。以上结果说明ABA处理可提高玉米幼苗光合作用的状态转换能力。 用的25μmol L-l ABA对玉米幼苗进行长时间(根系浇灌7天,LT)和短时间(实验前一天晚上叶面喷施1次,ST)处理,研究叶片C02同化、PsII化学活性,以及叶黄素循环的变化。结果表明在非光抑制状态下,LT与ST对玉米叶片光化学活性( Fv/Fm)及叶片羧化效率(CE)没有明显影响,但二者都引起叶片净光合速率(Pn)与气孔导度(Gs)下降。LT处理增大玉米叶片叶黄素循环库,而ST处理对该库大小没有影响。1500μmol m-2 s-1强光可明显引起玉米幼苗叶片Fv/Fm降低,但与对照幼苗相比,LT处理能显著减缓Fv/Fm降低。经60min强光照射后,ST与对照在Fv/Fm、фPS II、Pn和CE等参数上没有明显差异,但这些参数在LT处理的玉米幼苗中仍保持较高水平。LT处理幼苗叶黄素循环类色素含量及非光化学荧光猝灭(NPQ)都显著高于对照,膜脂过氧化产物MDA含量比对照低。而ST处理与对照在叶黄素循环类色素含量、NPQ和MDA含量等方面没有明显差异。以上结果说明ST处理对玉米幼苗光抑制没有明显影响,而LT处理可增强玉米幼苗抗光抑制能力,这可能与ABA处理使玉米幼苗在强光下维持较高的C02同化作用,以及其诱导叶片叶黄素循环增大有关。

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O objectivo deste trabalho, relaciona-­‐se com o levantamento de informação escrita relativa ao espólio documental deixado por José Francisco David Ferreira (JFDF), Cientista e Professor Catedrático da Faculdade de Medicina de Lisboa (FML) nascido em 1929 e falecido em 2012. Versa a descrição do processo e da metodologia utilizada, para o projecto em curso, de tratamento do espólio do Cientista e Professor José Francisco David Ferreira. Está enquadrado nos Espólios de Personalidades & Arquivos Científicos em História Contemporânea da Faculdade de Ciências Sociais e Humanas da Universidade Nova de Lisboa.

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Construir un instrumento psicométrico útil y válido para evaluar la eficacia de un programa de enseñanza alternativa basado en los contenidos del SOE, y para evaluar la capacidad adquirida por sujetos que han participado en programas de iniciación. Redefinir el término iniciación desde una perspectiva psicológica. Determinar un modelo de procedimiento de enseñanza y evaluación útil de actividad de ocio. La muestra la componían 117 individuos, alumnos de una escuela de vela. La investigación se articula en dos bloques; en el primero de ellos se plantea la iniciación a la vela desde una perspectiva histórica, sociológica y psicológica; desde esta última perspectiva se determinan los contenidos y habilidades que el sujeto iniciado debe poseer. A continuación se elabora un programa de enseñanza y evaluación basado en las teorías de Piagelin, inscritas dentro de la perspectiva genético-evolutiva de J. Piaget. En el segundo bloque se comprueba experimentalmente la validez del método mediante los instrumentos seleccionados y se analizan los datos desde las perspectivas psicométricas siguientes: test norma de grupo, test referidos al criterio y desde la teoría de respuesta de ítems. Test del lápiz y papel con ítems gráficos. Software para el análisis de ítems siguientes: UNIVAC, BICAL, ANCILLES, CALFIT, ITEMAN, BIG JIFFY, NOHARM, CREDIT, FML, BILOG, DISLOG, LOGISTY, TESTFACT, MICROCAT, MULTILOS, MIRTE, S/N, METRIX. Según software. Se confirma la importancia del planteamiento psicológico de un modelo de aprendizaje de la vela. Se observa que la excesiva tecnificación puede repercutir negativamente en la motivación aunque los resultados sean más positivos.

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The influences of hygrothermal conditioning on mechanical properties of a fiber/metal laminate (FML) have been investigated by tensile and compression tests. The environmental action, such as high moisture concentration, high temperatures, corrosive fluids or ultraviolet radiation (UV), can affect the performance of advanced composites during service. In the present work, the results show that for the glass fiber/epoxy composites tensile and compression values decrease after hygrothermal conditioning. However, no changes on mechanical properties (tensile and compression strength) are observed for the Glare laminate, regardless the hygrothermal conditioning. (C) 2006 Elsevier Ltd. All rights reserved.

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Continuous fiber/metal laminates (FML) offer significant improvements over current available materials for aircraft structures due to their excellent fatigue endurance and low density. Glass fibers/epoxy laminae and aluminum foil (Glare) are commonly used to obtain these hybrid composites. The environmental factors can limit the applications of composites by deteriorating the mechanical properties during service. Usually, epoxy resins absorb moisture when exposed to humid environments and metals are prone to surface corrosion. Therefore, the combination of the two materials in Glare (polymeric composite and metal). can lead to differences that often turn out to be beneficial in terms of mechanical properties and resistance to environmental influences. In this work. The viscoelastic properties. such as storage modulus (E') and loss modulus (E'), were obtained for glass fiber/epoxy composite, aluminum 2024-T3 alloy and for a glass fiber/epoxy/aluminum laminate (Glare). It was found that the glass fiber/epoxy (G/E) composites decrease the E' modulus during hygrothermal conditioning up to saturation point (6 weeks). However, for Glare laminates the E' modulus remains unchanged (49GPa) during the cycle of hygrothermal conditioning. The outer aluminum sheets in the Glare laminate shield the G/E composite laminae from moisture absorption. which in turn prevent, in a certain extent, the material from hygrothermal degradation effects. (c) 2005 Elsevier B.V. All rights reserved.

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Fiber metal laminates (FML) offer significant improvements over current available materials for aircraft structures due to their excellent mechanical characteristics and relatively low density. Non-destructive testing techniques are being used in the characterization of composite materials. Among these, vibration testing is one of the most used tools because it allows the determination of the mechanical properties. In this work, the viscoelastic properties such as elastic (E') and viscous (E) responses were obtained for aluminum 2024 alloy; carbon fiber/epoxy; glass fiber/epoxy and their hybrids aluminum 2024 alloy/carbon fiber/epoxy and aluminum 2024 alloy/glass fiber/epoxy composites. The experimental results were compared to calculated E modulus values by using the composite micromechanics approach. For all specimens studied, the experimental values showed good agreement with the theoretical values. The damping behavior, i.e. The storage modulus and the loss factor, from the aluminum 2024 alloy and fiber epoxy composites can be used to estimate the viscoelastic response of the hybrid FML. (c) 2005 Elsevier Ltd. All rights reserved.

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The effect of thermal-shock cycles on the mechanical properties of fiber-metal laminates (FMLs) has been evaluated. FML plates were composed by two AA2024 Al sheets (1.6 mm thick) and one composite ply formed by two layers of unidirectional glass fiber epoxy prepreg and two layers of epoxy adhesive tape of glass fiber reinforced epoxy adhesive. The set was manufactured by hand layup and typical vacuum bag technique. The curing cycle was in autoclave at 125 +/- 5 degrees C for 90 min and an autoclave pressure of 400 kPa. FML coupons taken from the manufactured plate were submitted to temperature variations between -50 and +80 degrees C, with a fast transition between these temperatures. Tensile and interlaminar shear strength were evaluated on samples after 1000 and 2000 cycles, and compared to nonexposed samples. 2000 Cycles corresponds to typical C Check interval for commercial aircraft maintenance programs. It was observed that the thermal-shock cycles did not result in significant microstructural changes on the FML, particularly on the composite ply. Similarly, no appreciable effect on the mechanical properties of FML was observed by the thermal-shock cycles. (c) 2012 Elsevier Ltd. All rights reserved.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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This study evaluated the performance of crude total antigen (CTA) and fucose-mannose ligand antigen (FML) in an enzyme-linked immunosorbent assay for diagnosis of canine visceral leishmaniasis (CVL). The assays used sera from known negative controls (n = 30), clinically symptomatic (n = 30) and oligosymptomatic (n = 30) parasitologically proven infection (by microscopy). Aspirates of popliteal lymph node from infected canines were colleted to score parasitism and compared with the ELISA results. The study indicated that FML used in ELISA provided high sensitivity for detecting oligosymptomatic dogs (90%) and CTA showed greater sensitivity than FML for symptomatic canines (90%). In oligosymptomatic dogs, specificity was 100% for CTA-ELISA, but in symptomatic dogs, FML specificity was higher (96.7%) than CTA-ELISA (93.3%). A significant correlation was observed between the degree of parasitism and the results obtained in CTA-ELISA. Since no available antigen offers 100% specificity and sensitivity for CVL diagnosis, the choice of antigen used must depend on the aim of the investigation. (C) 2008 Elsevier B.V. All rights reserved.

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Leishmune (R) vaccine is the first licensed vaccine against canine visceral leishmaniasis. It contains the Fucose-Mannose-ligand (FML) antigen of Leishmania donovani. The potential Leishmune (R) vaccine effect on the interruption of the transmission of the disease, was assayed by monitoring, in untreated (n = 40) and vaccinated dogs (n = 32) of a Brazilian epidemic area: the kala-azar clinical signs, the FML-seropositivity and the Leishmania parasite evidence by immunohistochemistry of skin and PCR for Leishmanial DNA of lymph node and blood samples. on month I I after vaccination, untreated controls showed: 25% of symptomatic cases, 50% of FML-seropositivity, 56.7% of lymph node PCR, 15.7% of blood PCR and 25% of immunohistochemical positive reactions. The Leishmune (R)-vaccinated dogs showed 100% of seropositivity to FML and a complete absence of clinical signs and of parasites (0%) in skin, lymph node and blood PCR samples (P < 0.01). The positivity in FML-ELISA in untreated dogs significantly correlates with the PCR in lymph node samples (p < 0.001) and with the increase in number of symptoms (p = 0.006) being strong markers of infectiousness. The absence of symptoms and of evidence of Leishmania DNA and parasites in Leishmune (R)-vaccinated animals indicates the non-infectious condition of the Leishmune (R)-vaccinated dogs. (c) 2005 Elsevier Ltd. All rights reserved.