760 resultados para MAGNA STRAUS


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Replication-defective adenoviruses have been utilized as candidate HIV vaccine vectors Few studies have described the international epidemiology of pre-existing immunity to adenoviruses We enrolled 1904 participants in a cross-sectional serological survey at seven sites in Africa, Brazil, and Thailand to assess neutralizing antibodies (NA) for adenovirus types Ad5, Ad6, Ad26 and Ad36 Clinical trial samples were used to assess NA titers from the US and Europe The proportions of participants that were negative were 14 8%(Ad5), 31 5%(Ad6),41 2%(Ad26) and 53.6% (Ad36) Adenovirus NA titers varied by geographic location and were higher in non-US and non-European settings, especially Thailand In multivariate logistic regression analysis, geographic setting (non-US and non-European settings) was statistically significantly associated with having higher Ad5 titers, participants from Thailand had the highest odds of having high Ad5 titers (adjusted OR = 3 53,95% CI 224,557) Regardless of location. titers of Ad5NA were the highest and Ad36 NA were the lowest Coincident Ad5/6 titers were lower than either Ad5 or Ad6 titers alone Understanding pre-existing immunity to candidate vaccine vectors may contribute to the evaluation of vaccines in international populations (C) 2009 Published by Elsevier Ltd

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Hydrocephalus is a common neurological problem in humans, Usually caused by an impairment of cerebrospinal fluid (CSF) flow or absorption. A reliable induced model of chronic hydrocephalus in mice would be useful to test hypotheses using genetic mutants. Our goal was to characterize behavioral and histological changes in juvenile and Young adult mice with kaolin (aluminum silicate) -induced hydrocephalus. Seven-day old and 7-8 week old mice received injection of kaolin into the cisterna magna. Behavior was assessed repeatedly. Seven or 14 days following kaolin, magnetic resonance (MR) imaging was used to assess ventricle size. In hydrocephalic mice, body weight was significantly lower than in age-matched saline-injected sham controls and the gait and posture score were impaired. Juvenile mice developed severe ventriculomegaly and had reduced corpus callosum thickness with gross white matter destruction by 14 days. Reactive astroglial change in white matter and cortex and reduced cellular proliferation in the subependymal zone were also apparent. Young adult mice developed only moderate ventricular enlargement without overt white matter destruction, although there was corpus callosum atrophy and mild astroglial reaction in white matter. Glial fibrillary acidic protein content was significantly higher in juvenile and young adult hydrocephalic mice at 7 and 14 days, but myelin basic protein content was not significantly altered. In conclusion, hydrocephalus induced by percutaneous injection of kaolin in juvenile and young adult mice is feasible. The associated periventricular alterations are essentially the same as those reported in rats of comparable ages. (C) 2009 Elsevier Inc. All rights reserved.

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After liver transplantation, migration of donor-derived hematopoietic cells to recipient can be detected in pheripheral blood. This state is termed microchimerism. The aim of this study was to investigate prospectively the presence of allogeneic microchimerism, the occurrence of acute cellular rejection and the level of immunosuppression in transplanted patients. Microchimerism occurrence between 10 days and 12 months after liver transplantation was analyzed in 47 patients aged between 15 and 65 by a two-stage nested PCR/SSP technique to detect donor MHC HLA-DR gene specifically. A pre-transplant blood sample was colleted from each patient to serve as individual negative control. Microchimerism was demonstrated in 32 (68%) of the 47 patients; of these, only 10 patients (31.2%) presented rejection. Early microchimerism was observed in 25 patients (78.12%) and late microchimerism in 7 patients (21.8%). Among the patients with microchimerism, 14 were given CyA and 18 were given FK506. In the group without microchimerism, 12 patients were given CyA and 03 were given FK506. There was a significant association between the presence of microchimerism and the absence of rejection (p=0.02) and also between microchimerism and the type of immunosuppression used. Our data indicate that microchimerism and probably differentiation of donor-derived leukocytes can have relevant immunologic effects both in terms of sensitization of recipient and in terms of immunomodulation toward tolerance induction. (C) 2008 Elsevier B.V. All rights reserved.

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Background The strongest genetic marker for psoriasis is Cw*06. Polymorphisms in the tumor necrosis factor (TNF)-alpha promoter region, especially replacement of guanine with adenine in positions -238 and -308 are related to higher TNF-alpha production and higher risk for psoriasis in Caucasoid populations, not found in Asians. We performed a case-control study of 69 patients with psoriasis type I and 70 controls, characterized clinical progression along 10-years of follow-up in mild or severe disease and determined HLA class I, II, and TNF single nucleotide polymorphisms (SNPs) -238 and -308 polymorphisms to demonstrate whether these polymorphisms may be genetic risk for susceptibility to psoriasis or severity of the disease in Brazilians. Methods Polymorphisms were identified using PCR/SSP. Alleles, genotypes, and haplotypes frequencies were compared using Fisher`s test. Results More severe disease was found in male patients. It may be suggested that alleles B*37, Cw*06, Cw*12, and DRB1*07 were associated with severe disease course, while B*57 with mild disease. No statistical difference was found between the patients and controls regarding polymorphisms frequencies in TNF SNPs. This study pointed to a higher TNF-238 G/G genotype frequency (OR: 3.21; CI: 1.06-9.71; P = 0.04) in the group with severe disease. Conclusions Polymorphisms in the TNF-alpha SNPs do not seem to be a more important genetic risk factor for psoriasis than the already known Cw*06 in Brazilian patients, but these markers may be related to clinical manifestations.

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Systemic administration of cannabidiol (CBD), a non-psychotomimetic compound from Cannabis sativa, attenuates the cardiovascular and behavioral responses to restraint stress. Although the brain structures related to CBD effects are not entirely known, they could involve brainstem structures responsible for cardiovascular control. Therefore, to investigate this possibility the present study verified the effects of CBD (15.30 and 60 nmol) injected into the cisterna magna on the autonomic and behavioral changes induced by acute restraint stress. During exposure to restraint stress (1 h) there was a significant increase in mean arterial pressure (MAP) and heart rate (HR). Also, 24 h later the animals showed a decreased percentage of entries onto the open arms of the elevated plus-maze. These effects were attenuated by CBD (30 nmol). The drug had no effect on MAP and HR baseline values. These results indicate that intracisternal administration of CBD can attenuate autonomic responses to stress. However, since CBD decreased the anxiogenic consequences of restraint stress, it is possible that the drug is also acting on forebrain structures. (C) 2011 Elsevier Inc. All rights reserved.

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Dopamine (DA) is a neuromodulator in the brainstem involved with the generation and modulation of the autonomic and respiratory activities. Here we evaluated the effect of microinjection of DA intracistema magna (icm) or into the caudal nucleus tractus solitarii (cNTS) on the baseline cardiovascular and respiratory parameters and on the cardiovascular and respiratory responses to chemoreflex activation in awake rats. Guide cannulas were implanted in cisterna magna or cNTS and femoral artery and vein were catheterized. Respiratory frequency (f(R)) was measured by whole-body plethysmography. Chemoreflex was activated with KCN (iv) before and after microinjection of DA icm or into the cNTS bilaterally while mean arterial pressure (MAP), heart rate (HR) and f(R) were recorded. Microinjection of DA icm (n = 13), but not into the cNTS (n = 8) produced a significant decrease in baseline MAP (-15 +/- 1 vs 1 +/- 1 mm Hg) and HR (-55 +/- 11 vs -11 +/- 17 bpm) in relation to control (saline with ascorbic acid, n = 9) but no significant changes in baseline f(R). Microinjection of DA icm or into the cNTS produced no significant changes in the pressor, bradycardic and tachypneic responses to chemoreflex activation. These data show that a) DA icm affects baseline cardiovascular regulation, but not baseline f(R) and autonomic and respiratory components of chemoreflex and b) DA into the cNTS does not affect either the autonomic activity to the cardiovascular system or the autonomic and respiratory responses of chemoreflex activation. (C) 2010 Elsevier B.V. All rights reserved.

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The Bandas del Sur Formation preserves a Quaternary extra-caldera record of central phonolitic explosive volcanism of the Las Canadas volcano at Tenerife. Volcanic rocks are bimodal in composition, being predominantly phonolitic pyroclastic deposits, several eruptions of which resulted in summit caldera collapse, alkali basaltic lavas erupted from many fissures around the flanks. For the pyroclastic deposits, there is a broad range of pumice glass compositions from phonotephrite to phonolite. The phonolite pyroclastic deposits are also characterized by a diverse, 7-8-phase phenocryst assemblage (alkali feldspar + biotite + sodian diopside + titanomagnetite + ilmenite + nosean-hauyne + titanite + apatite) with alkali feldspar dominant, in contrast to interbedded phonolite lavas that typically have lower phenocryst contents and lack hydrous phases. Petrological and geochemical data are consistent with fractional crystallization (involving the observed phenocryst assemblages) as the dominant process in the development of phonolite magmas. New stratigraphically constrained data indicate that petrological and geochemical differences exist between pyroclastic deposits of the last two explosive cycles of phonolitic volcanism. Cycle 2 (0.85-0.57 Ma) pyroclastic fall deposits commonly show a cryptic compositional zonation indicating that several eruptions tapped chemically, and probably thermally stratified magma systems. Evidence for magma mixing is most widespread in the pyroclastic deposits of Cycle 3 (0.37-0.17 Ma), which includes the presence of reversely and normally zoned phenocrysts, quenched mafic glass blebs in pumice, banded pumice, and bimodal to polymodal phenocryst compositional populations. Syn-eruptive mixing events involved mostly phonolite and tephriphonolite magmas, whereas a pre-eruptive mixing event involving basaltic magma is recorded in several banded pumice-bearing ignimbrites of Cycle 3. The periodic addition and mixing of basaltic magma ultimately may have triggered several eruptions. Recharge and underplating by basaltic magma is interpreted to have elevated sulphur contents (occurring as an exsolved gas phase) in the capping phonolitic magma reservoir. This promoted nosean-hauyne crystallization over nepheline, elevated SO3 contents in apatite, and possibly resulted in large, climatologically important SO2 emissions.

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São descritas e ilustradas Apenesia longa sp. nov., A. peccata sp. nov., A. magna sp. nov., A. permaxima sp. nov., A. perconcava sp. nov. e A. recta sp. nov. da região Neotropical. São adicionados dados novos de variações estruturais e distribuição geográfica de A. transversa Evans, 1963, A. spinipes Evans, 1969, A. tlahuicana Evans, 1963, A. triangula Azevedo & Batista, 2002, A. megaventris Azevedo & Batista, 2002, A. venezuelana Evans, 1963, A. acia Lanes & Azevedo, 2004 e A. ventosa Azevedo & Batista, 2002. Duas sinonímias novas são propostas: A. peruana Evans, 1963 como sinônimo junior de A. brasiliensis (Kieffer, 1910); A. subangulata Azevedo & Batista, 2002 como sinônimo junior de A. fulvicollis (Westwood, 1874), esta ultima considerada dentro ao grupo nitida. É fornecida uma chave de identificação para as espécies do grupo, baseada em machos.

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Os glicoesfingolipídios (GSLs) são importantes componentes da membrana celular, organizados em microdomínios, relacionados a receptores de membrana e comportamento anti-social da célula neoplásica como crescimento descontrolado, invasão e ocorrência de metástases. OBJETIVO: Como a expressão de GSLs no carcinoma espinocelular (CEC) é tema pouquíssimo estudado decidiu-se realizar estudo prospectivo visando avaliar a expressão de GSLs no CEC do trato aerodigestivo superior. MÉTODO: Coletou-se 33 amostras de CEC e mucosa normal e GSLs extraídos e purificados por cromatografia de fase reversa em coluna de C-18 e hidrólise alcalina em metanol. Os GSLs foram quantificados por densitometria das placas de cromatografia de alta resolução em camada delgada coradas com orcinol. RESULTADOS: Observou-se aumento significativo de GSLs no CEC (3,57µg/mg) em comparação à mucosa normal (1,92µg/mg), principalmente do monosialogangliosídeo (GM3), trihexosilceramida (CTH), dihexosilceramida (CDH), globosídeo (Gb4). A expressão de monohexosilceramida (CMH) foi semelhante no CEC e na mucosa normal. O aumento do GM3 no CEC foi demonstrado por métodos imunoquímicos empregando-se MAb DH2 (anti-GM3). Analisando-se os carboidratos do CMH por cromatografia gasosa acoplado a espectrômetro de massa constatou-se que a mucosa normal expressa glucosilceramida e o CEC glucosilceramida e galactosilceramida. CONCLUSÃO: O aumento de GSLs no tecido tumoral pode representar alterações dos microdomínios da membrana celular resultantes do processo de transformação maligna, responsáveis por uma maior interação célula-célula e célula-matriz aumentando seu potencial de infiltração e metástase, possibilitando o emprego dos GSLs e de MAbs no diagnóstico e no tratamento do CEC, a exemplo do que ocorre no melanoma.

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A ressecção do ramo ascendente da mandíbula ocasiona um déficit funcional e estético considerável. OBJETIVO: Comparar a mandibulectomia marginal e segmentar de tumores avançados de loja amigdalina e região retromolar sem envolvimento ósseo mandibular detectado no período pré-operatório, em relação à sobrevida e recidiva loco-regional. Forma de Estudo: Estudo de coorte contemporânea com corte transversal. MATERIAL E MÉTODO: Compararam-se 20 pacientes tratados com mandibulectomia marginal e 22 tratados com mandibulectomia segmentar de outubro de 1994 a dezembro de 2001 em serviço de referência em Cirurgia de Cabeça e Pescoço. RESULTADOS: Dos 20 pacientes tratados com mandibulectomia marginal, 35% morreram com doença, 15% por recidiva local, 15% por recidiva regional e 5% por recidiva loco-regional. Dos 22 pacientes tratados com mandibulectomia segmentar 45,4% morreram pela doença, sendo 31,8% por recidiva local e 13,6% por recidiva à distância. Na análise pelo método de Kaplan-Meier o grupo tratado com mandibulectomia marginal apresentou uma taxa de 55%, e o grupo tratado com ressecção segmentar 45% com p= 0,8329. CONCLUSÕES: A análise dos dois grupos evidenciou que a conservação do ramo ascendente da mandíbula, mesmo em lesões avançadas, sem envolvimento mandibular, não aumenta o índice de recidiva.

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A eficiência da adubação nitrogenada do tomateiro, na presença da adubação orgânica, foi avaliada em dois experimentos de campo conduzidos em duas épocas: primavera/verão (nov./98 a fev./99) e outono/primavera (maio/99 a out/99). Os dois experimentos foram instalados na horta da Universidade Federal de Viçosa, em solo da classe Argissolo Vermelho-Amarelo Câmbico. Em ambos, as doses de N aplicadas, na forma de nitrocálcio, foram 0,0; 93,3; 187,0; 374,0; e 748,0 kg/ha, e as doses de adubação orgânica, na forma de esterco bovino curtido, foram 0 e 8 t/ha de matéria seca. Os experimentos seguiram o delineamento em blocos ao acaso, no arranjo fatorial 5 x 2, com quatro repetições. O peso e o número de frutos comercializáveis de tomate, por planta, são aumentados com o aumento do nível de N no solo. A percentagem de frutos comercialmente desclassificáveis é maior na primavera/verão do que no outono/primavera. A eficiência da adubação nitrogenada pelo tomateiro é maior no outono/primavera do que na primavera/verão. Na primavera/verão ela foi maior quando não houve adição de matéria orgânica ao solo, o contrário ocorrendo no outono/primavera.

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Este trabalho teve como objetivo avaliar a patogenicidade e a agressividade de três raças de Cercospora sojina, em dois cultivares de soja, BMX Magna e Bragg. Para isso, preparou-se suspensão, na concentração de 40 x 10³ conídio mL-1, para inoculação das plantas. Quinze dias após a inoculação com o fungo, verificou-se que a severidade e o número de lesões por folíolo, para a raça 23, não apresentaram diferenças estatísticas entre os cultivares. Para as raças 24 e 25, o cultivar BMX Magna apresentou maior valor do grau de infecção, diferindo estatisticamente daquele do cultivar Bragg. Com relação ao diâmetro das lesões, para a raça 23, o cultivar Bragg apresentou maior valor, para a raça 24, o maior valor ocorreu em BMX Magna e para a raça 25, não houve diferença estatística entre os cultivares. Portanto, as raças de C. sojina são patogênicas para os dois cultivares de soja e há diferença de agressividade entre elas, sendo as raças 24 e 25 mais agressivas do que a raça 23.

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Objetivou-se, com este trabalho, determinar parâmetros de crescimento e de rendimento da cana-de-açúcar cv. RB92579, sob regime de irrigação, no Semiárido brasileiro, visando a avaliar o desempenho desta cultura nas condições edafoclimáticas locais. Foram avaliados o acúmulo de biomassa seca e as suas respectivas partições, durante dois ciclos consecutivos de cana-de-açúcar (soca e ressoca), além dos indicadores de rendimento e de qualidade da cultura ao final do período experimental. Em ambos os ciclos, foram realizadas dez coletas de amostras para se determinar a biomassa seca de seis componentes estruturais dos perfilhos (folhas verdes, bainhas, parte emergente, pseudocolmos, folhas e bainhas mortas e colmo). A cana-de-açúcar apresentou elevado acúmulo de biomassa seca da parte aérea da planta, com valor médio de 6.493 g m-2 para os dois ciclos de cultivo. No início do seu crescimento, os fotoassimilados foram destinados prioritariamente às folhas verdes, bainhas, parte emergente e pseudocolmos. Em fase posterior de crescimento, os fotoassimilados passaram a ser utilizados na formação dos colmos. Os resultados obtidos foram muito semelhantes para os ciclos de soca e ressoca. Os modelos ajustados para descrever a evolução da biomassa seca e de suas respectivas partições apresentaram ajustes satisfatórios, em função dos dias após o corte. O elevado rendimento industrial (133,88 ± 40,84 t ha-1) e a alta concentração de sacarose por biomassa seca (0,34 ± 0,10 g g-1) proporcionaram valores elevados de produção de açúcar (17,75 ± 4,44 t ha-1) e de álcool (12,73 ± 3,23 t ha-1), indicando alto desempenho produtivo da RB92579 para a região.