bluuebunny/crossref_metadata_2025 huggingface dataset:
Características da estrutura de um podzólico vermelho amarelo da Estação Experimental de Monte Alegre do Sul
Authors: Queiroz Neto José Pereira de , Oliveira J. Bertoldo de , Grohmann Francisco
Published: April 2009

Com a finalidade de definir o estado estrutural de um podzólico vermelho amarelo-orto, bem como a sua variação frente a diferentes formas de uso, foram feitas as análises de amostras de solo das seguintes parcelas da Estação Experimental de Monte Alegre do Sul: a)cultura de milho durante 15 anos; b)pomar de frutas de clima temperado, em produção; c) eucalipto de 2.° corte. Procedeu-se à análise granulométrica e às determinações de pH, C e N totais, Ca++, Mg++ e K+ trocáveis. Foram determinados o estado de agregação, por peneiragem a sêco, e a estabilidade nágua dos gregados. Os resultados mostraram redução do diâmetro médio geométrico dos agregados da parcela "eucalipto" (2,55 mm) para a "pomar" (2,35 mm) e desta para "milho" (2,25 mm). A redução da estabilidade nágua na parcela cultivada anualmente foi muito sensível: 87% dos agregados de "eucalipto" foram estáveis nágua, ao passo que de "milho" só 31% o foram. Os autores discutem as causas dêsse comportamento do solo.
Adaptação de um pulverizador de tração humana para aplicação localizada de herbicidas
Authors: Viliotti C.A. , Vieira L.B. , Ferreira L.R. , Dias G.P. , Rinaldi P.C.N.
Published: April 2009

Objetivou-se com este trabalho adaptar um pulverizador de tração humana para aplicação localizada de herbicidas. Para o desenvolvimento do circuito eletrônico, foi elaborado um programa computacional em linguagem Assembly, com informações sobre a variação da resistência elétrica no LDR (Resistor Dependente de Luz) referente à radiação global incidente e refletida para quatro tipos de superfícies diferentes (plantas dicotiledôneas, plantas monocotiledôneas, palhada de trigo e solo). Concluiu-se que é possível e economicamente viável a utilização do sensor LDR para detecção de plantas daninhas.
O discurso político sobre a educação no Brasil autoritário
Authors: Germano José Willington
Published: April 2009

Este artigo procura explicitar o discurso político autoritário sobre a educação no Brasil e sua materialização em políticas educacionais pós-1964. Embora tenha como objetivo focalizar o período que se inaugura com o golpe civil/militar de 1964, recua no tempo histórico, até os anos de 1930. Isso evidenciou o processo de constituição de um imaginário social instituinte, no tocante ao papel das Forças Armadas, em particular do Exército, para o desenvolvimento do país. Ao longo do tempo, foi se plasmando um pensamento militar, ancorado no tema ordem e progresso, sobre a sociedade brasileira e acerca do Estado, necessário para desenvolver o país, e a educação requerida para dar sustentáculo ao projeto de nação almejado pelos "homens de farda". Observa-se que as intervenções militares na política efetuadas a partir do Estado Novo (1937-1945) tiveram caráter conservador e salvacionista, ganhando relevo no âmbito militar, de 1937 a 1964, a idéia do Exército como educador do povo, para além dos quartéis.
Situação de Sítio
Authors: Simon Iumna Maria
Published: April 2009

No panorama recente da poesia brasileira surpreendeu o aparecimento, em 2001, do poema "Sítio", de Claudia Roquette-Pinto, poeta até então tida como intimista, metaforizante, trancada no seu mundo privado e burguês. O foco desta abordagem é discutir como foi possível à autora formular nesse poema um estudo sobre o medo e a violência, sem abrir mão da sua imagética introspectiva e da sua experiência poética anterior, centrada numa escrita referencialmente rarefeita. A análise em detalhe do poema procura registrar a conversão da opacidade, do lacunar e da indeterminação em elementos de caracterização da violência urbana e da miséria emocional dos protegidos. Aí se entrelaçam portanto a atualidade do processo histórico-social brasileiro, a vulnerabilidade da poesia e as carências do sujeito poético.
Determinantes da duração esperada do emprego urbano e rural no Nordeste brasileiro
Authors: Monte Paulo Aguiar do , Penido Mariângela Rangel Jacques
Published: April 2009

Este trabalho tem como objetivo analisar os determinantes da duração no emprego nos estados do Nordeste para os anos 1993 e 2003. Para tanto, foram utilizados os microdados da Pesquisa Nacional por Amostra de Domicílios (PNAD), realizada pelo Instituto Brasileiro de Geografia e Estatística (IBGE). Os resultados obtidos por meio do modelo paramétrico evidenciam que a duração das relações de emprego é maior para os homens, chefes-de-família, brancos e trabalhadores com idade mais elevada. No que tange ao aspecto regional, verificou-se que os residentes nos estados de Pernambuco e Bahia - justamente os que possuem as maiores taxas de desemprego - apresentam maior rotatividade quando comparado aos demais estados nordestinos.
Métodos para predição de bitter pit em maçãs 'Fuji' e 'Braeburn'
Authors: Sestari Ivan , Neuwald Daniel Alexandre , Giehl Ricardo Fabiano Hettwer , Weber Anderson , Brackmann Auri
Published: April 2009

Experimentos foram conduzidos com objetivo de avaliar a eficiência de métodos para predição da ocorrência de bitter pit em maçãs 'Fuji' e 'Braeburn' em duas épocas de amostragem. Os frutos, provenientes de seis pomares distintos, três para cada cultivar, foram coletados antecipadamente (20 dias em relação à colheita) e na data prevista para a colheita comercial. Os métodos de predição utilizados foram: a) infiltração dos frutos com solução 0,10M MgCl2 mais 0,01% Tween-20 e 0,4M de sorbitol; b) imersão dos frutos em solução com 2500nL L-1 de ethephon mais 0,01% Tween-20. Os frutos foram armazenados em atmosfera controlada (AC) por cinco meses mais 12 dias, a 20°C, simulando a incidência real de bitter pit em armazenamento comercial. Cada tratamento foi constituído por quatro repetições de 25 frutos. A incidência e severidade de bitter pit, prevista por ambos os métodos foi semelhante à ocorrência real de bitter pit após o armazenamento em atmosfera controlada para cada uma das cultivares utilizadas, quando os frutos foram amostrados antecipadamente em relação à colheita comercial. Na avaliação realizada com frutos amostrados na colheita comercial, nenhum dos métodos foi capaz de prever a incidência de bitter pit após o armazenamento de maneira confiável. Para ambas as cultivares, a infiltração com magnésio e a imersão dos frutos em ethephon só são eficientes na predição da incidência de bitter pit em frutos coletados 20 dias antes da colheita comercial.
A multidimensionalidade nas organizações empresariais: proposta de um modelo analítico
Authors: Alves Sérgio
Published: April 2009

O modelo proposto neste artigo tem por fundamento teórico o legado de Max Weber, principalmente a sua tipologia da ação social e os seus tipos ideais de dominação, cujos componentes são reelaborados para a construção de instrumental analítico capaz de contribuir para investigar configurações administrativo-organizacionais. O modelo ressalta a coexistência, no interior da organização empresarial, de um conjunto de fenômenos simultaneamente opostos e complementares, em meio a um processo contínuo de organização-interações-reordenamento. A empresa dotada de uma estrutura equiparativo-adaptadora é o tipo-base do modelo, a partir do qual são descritos os subtipos ordenativo-conservador e liberativo-transformador. Este trabalho insere novos elementos no debate sobre como integrar flexibilidade, autonomia e liberdade, que propiciam a inovação e a criatividade, com estabilidade, padronização e regulamentação, que favorecem a disciplina administrativa e o controle gerencial.
Avaliação da satisfação do consumidor utilizando o método de equações estruturais: um modelo aplicado ao setor elétrico brasileiro
Authors: Marchetti Renato , Prado Paulo H. M.
Published: April 2009

Este artigo apresenta o Modelo de avaliação da Satisfação do Consumidor quanto ao Setor Elétrico Brasileiro, baseado em Modelo de Equações Estruturais. Nele, inseriram-se os construtos da Desconformidade com os serviços de distribuição de energia elétrica, avaliados a partir da percepção dos seus diversos componentes e do valor percebido como antecedentes da Satisfação. Também criou-se uma variável latente, representando a Satisfação Global, que foi utilizada para avaliar os resultados globais de cada concessionária de energia. Complementando o modelo, inseriu-se também o construto da fidelidade, avaliado por meio de cenários em que o consumidor era exposto a vantagens, verificando-se se este tinha intenção de troca. Os resultados obtidos indicam um modelo de grande validade e consistência interna, bem como flexibilidade para mensurar a Satisfação em diversas situações (para diferentes portes de empresa, regiões do país etc.). Da mesma forma, a replicação desta metodologia em outros setores da economia brasileira permitem a comparação de desempenho entre elas e com benchmarks internacionais, hoje difundidos pelo mundo.
Ecology of the parasitic endohelminth community of Pseudoplatystoma fasciatum (Linnaeus, 1776) (Siluriformes: Pimelodidae) from the Aquidauana River, Pantanal, State of Mato Grosso do Sul, Brazil
Authors: Campos CM. , Fonseca VE. , Takemoto RM. , Moraes FR.
Published: April 2009

This study investigated the structure and diversity of the endohelminth community and its interactions with Pseudoplatystoma fasciatum, caught in the Aquidauana River, in the State of Mato Grosso do Sul, Brazil. Ten helminth species were represented in 1,228 specimens of parasites found in the intestine and mesentery of 33 specimens of P. fasciatum. Cestodes were observed in the intestine, while nematodes Cucullanus sp. in the mesentery. Contracaecum sp. Type 1, Spatulifer rugosa and Choanoscolex abscisus showed the highest mean intensity and mean abundance and Nomimoscolex sudobin showed the highest prevalence. Simpson's index indicated dominance in the endohelminth infracommunities (C = 1.0792) and Choanoscolex abscisus was considered the central species. A clumped pattern of dispersion according to Green's index was related. 69.69% of hosts analyzed had between 2 and 5 species of endohelminths. Mean diversity was H = 0.5517 (SD = 0.4209). Two pairs of species showed significant positive association and four pairs presented significant positive correlation among abundance data. Significant negative correlations between total length and prevalence and abundance of Peltydocotyle rugosa and Nomimoscolex sudobim were found. However, no significant correlation was observed between condition factor and abundance, as well as total length and diversity. There was significant prevalence of Harriscolex kaparari in male hosts.
Reproduction of Cubaris murina (Crustacea: Isopoda) under laboratory conditions and its use in ecotoxicity tests
Authors: Niemeyer JC. , Santos VC. , Araújo PB. , da Silva EM.
Published: April 2009

Reproduction of the isopod Cubaris murina was studied in the laboratory in order to observe the offspring number per brood, the number and duration of the incubation periods, and the influence of repeated mating on number of young per brood. An experiment was conducted with two different groups: female/male pairs and females that were isolated after mating. No significant difference was found between the two reproductive female groups for the mean number of young per brood (x = 25) and the duration of the incubation periods (x = 17 days). One mating was enough for at least five broods, with no reduction in brood size. There was no significant difference between the number of adult males and females. Low-density cultures had a significantly higher growth rate compared to high-density cultures. Furthermore, the experimental results for optimization isopod culture conditions for terrestrial ecotoxicity testing are reported.
Histological and histochemical analysis of the gonadal development of males and females of Armases rubripes (Rathbun 1897) (Crustacea, Brachyura, Sesarmidae)
Authors: Santos CM. , Lima GV. , Nascimento AA. , Sales A. , Oshiro LMY.
Published: April 2009

The objective of this study was to provide information on the histological characteristics of the gonads of male and female Armases rubripes crabs, and to try to establish a relationship between the microscopic and macroscopic stages previously identified. Thirty-six crabs were collected by hand between February 2003 and January 2004 in banks of Spartina alterniflora on Sahy Beach in Mangaratiba, Rio de Janeiro state, Brazil. The histological analysis of the ovaries of A. rubripes demonstrated a gradual process of development of the oocytes. According to their cellular characteristics, five types of cells were distinguished: oogonia, oocyte I, oocyte II, oocyte III and oocyte IV. The ovaries showed four stages during gonadal activity: stage I (rudimentary), stage II (developing or maturing), stage III (developed or mature) and stage IV (resting). The results of the histochemical analyses showed that the ovaries vary according to the gonad development stage. The histological aspect of one section of the male gonad was always the same in all of the seminiferous tubules, where the lumen of these tubules always contained spermatozoa and/or spermatids. It was not possible to characterize the three stages of gonad development in the males. This agrees with previous reports in the literature. However, in the females there was a relationship between the gonad stages distinguished macroscopically and the results obtained through the histological and histochemical analysis, due to the presence of different cell types, as well as the lysis process and reabsorption of the oocytes in spent females.
Frugivory in Lacistema hasslerianum Chodat (Lacistemaceae), a gallery forest understory treelet in Central Brazil
Authors: Melo C. , Oliveira PE.
Published: April 2009

The objectives of this study were to know and to characterize the behavioural patterns of frugivorous birds in Lacistema hasslerianum. The study was carried out in the Panga Ecological Station (Uberlândia, Minas Gerais State). During the frutification time (September-October), L. hasslerianum was observed for 31.25 hours and received 58 visits by five species of birds. Tyrannidae was the best represented family (2 species). Pipridae was the most frequent visitor in L. hasslerianum (68.97% of visits). The number of consumed fruits was correlated with the time of permanence on the plant. The main foraging tactic was "Stalling" (58.62%) and the most frequent fruit consumption strategy was "swallower" (45.25%), which indicates a high seed dispersal potential. Antilophia galeata (Pipridae), although a territorial bird, presented the best dispersal efficiency for Lacistema hasslerianum, because of its consumption rate (2.82 whole fruits consumed/minute).
Phosphorus recovery from wastewater: needs, technologies and costs
Authors: Cornel P. , Schaum C.
Published: April 2009

Phosphorus is an essential, yet limited resource, which cannot be replaced by any other element. This is why there are increasing efforts to recycle phosphorus contained in wastewater. It involves the recovery of phosphorus and, normally, the separation of phosphates from harmful substances. Phosphorus can be recovered from wastewater, sewage sludge, as well as from the ash of incinerated sewage sludge, and can be combined with phosphorus removal in most cases. The phosphorus recovery rate from the liquid phase can reach 40 to 50% at the most, while recovery rates from sewage sludge and sewage sludge ash can reach up to 90%. There are various methods which can be applied for phosphorus recovery. Up to now, there is limited experience in industrial-scale implementation. The costs for recovered phosphate exceed the costs for phosphate from rock phosphate by several times. For German conditions, the specific additional costs of wastewater treatment by integrating phosphorus recovery can be estimated at €2–6 per capita and year.
Ammonia influence in anaerobic digestion of OFMSW
Authors: Benabdallah El Hadj T. , Astals S. , Galí A. , Mace S. , Mata-Álvarez J.
Published: April 2009

The anaerobic digestion of the organic fraction of municipal solid wastes is taking increasing importance in the recent years. The main problem of some anaerobic digestion process is the large quantity of ammonia that is released, especially when high solid digestion is implemented. A fraction of the supernatant is treated and the remaining is recirculated to maintain the reactor in the optimum solids concentration. The question arising is if this recirculation stream should also be treated to improve biogas production. However, when doing the latter the quantity of ammonia inside the reactor increases too which could lead to inhibit the reactor operation. In this paper it appears that not only free ammonia affects the methanogenic fermentation but also ammonium ion concentration. Biogas production profiles are estimated using the Gompertz model. On the other hand, inhibition constants are fitted using a non-competitive inhibition model equation Thus, 50% inhibition of biomethane production was observed at level of 215 and 468 mg NH3_N/L under mesophilic and thermophilic conditions. However, the methane generation under mesophilic and thermophilic conditions was reduced by 50% when ammonium ion reach concentrations of 3,860 and 5,600 mg NH4+_N/L respectively. Under mesophilic conditions, pH higher than 7 impacted the methanogens bacteria negatively. This threshold pH limit, is variable under thermophilic conditions, depending on the total ammonia concentration.
Foodwaste as a co-substrate in a fed-batch anaerobic biowaste digester for constant biogas supply
Authors: Nayono Satoto E. , Gallert Claudia , Winter Josef
Published: April 2009

The use of foodwaste as a supplementary substrate for an anaerobic municipal biowaste digester during night times and as the sole substrate during weeks ends, when no biowaste suspension was available was studied in order to equilibrate biogas production. Assays were performed in semi-continuously fed laboratory reactors with real substrates, simulating practical feed conditions. Biogas production of biowaste or foodwaste reached 0.39 or 0.52 m3·kg−1 CODadded, with an average methane content of 62–66%, respectively. By foodwaste co-digestion during the night in a semi-continuously fed bioreactor, the total biogas production of the reactor increased by 21–37% compared to biogas production during biowaste-only-fed periods during the day and no feeding during the night. After three weeks of supplemenary foodwaste digestion during the nights and during week ends, the COD elimination efficiency of the reactor reached the same level as in biowaste-only-fed periods (51–65%). During co-digestion of foodwaste with biowaste, the volatile solids elimination efficiency was between 62–65%, which was insignificantly less compared to the volatile solids elimination during biowaste-only-fed periods (63–68%).
Advanced Control for a Fire-Tube Shell Boiler System
Authors: Abu Bakar Tarmidi , Hussain Mohamed Azlan
Published: April 2009

The design of a fire-tube shell boiler consists of a bundle of tubes contained inside a shell. The heat transfer process from the combustion gas to the boiling water via the tube surface is extremely complicated as it involves combustion, convection, conduction, and boiling process. Severe boiling and evaporating processes take place outside the fire-tube shell boiler where the steam is generated. However, many processes such as the regeneration of absorbent for CO2 removal needs optimum steam consumption, which reflects its high costs for operation. Therefore, good control performance of steam pressure becomes important. This study is aimed at developing a control scheme to minimize the effect of over-firing on the fire-tube shell boiler which impacts on excessive fuel consumption. The Neural Network Predictive Controller (NNPC) is used in this work, using the optimization and neural toolboxes which are written in the MATLAB code and were compared with the PID controller for set-point tracking and disturbance rejection ability. The comparison reveals that NNPC gives an excellent alternative to PID controller due to the non-linearity of the fire-tube shell boiler system. Since NNPC can reduce the fuel consumption by minimizing actuator moves, the control of boiler and burners in this plant in Brunei is recommended to be upgraded to replace the existing PID controller.
TEACHER SELF-EFFICACY BELIEF
Authors: Erdem Eda , Demirel Özcan
Published: April 2009

This study presents development and validation of a new measurement instrument to explore student-teachers' self-efficacy beliefs toward teaching. We developed and administered a survey to 346 student teachers at Hacettepe University, Ankara, Turkey in the Department of Elementary
Education in the spring term of the 2003–2004 academic year. The nature of the study is descriptive. The aim is to describe what the real situation is. Standard scale development methods and factor analysis were used. The results of the study were strongly supported by the validity and
reliability of the survey. Cronbach's alpha was calculated and the reliability coefficient was 0.92. For purposes of examining content validity, the opinions of experts on 5 subject matters were taken. Factor analysis was made to elicit the fundamental dimensions of the survey. As a result
of the Kalse-Meyer-Olkin and Bartlett test (0.93), factor analysis was administered to the survey. A single-factor model was specified for the structure of the survey as anticipated.
THE EFFECTS OF QUALITY OF WORK LIFE ON COMMITMENT AND TURNOVER INTENTION
Authors: Huang Tung-Chun , Lawler John , Lei Ching-Yi
Published: April 2009

Although previous studies have demonstrated the importance of balance between family and work life, few have included quality of work life (QWL) and job-related attitudes. The aim of this study was to examine the impact of quality of work life on auditors' career and organizational
commitment in Taiwanese public accounting firms, and how those commitments, in turn, affect turnover intention. Our findings indicate that different dimensions of QWL result in distinctive effects on organizational and career commitments and turnover intentions. Managerial implications for
both researchers and practitioners are discussed.
AN EXAMINATION OF THE CORRELATION BETWEEN DEPRESSION AND HOPELESSNESS LEVELS IN MOTHERS OF DISABLED CHILDREN
Authors: Ceylan Remziye , Aral Neriman
Published: April 2009

This research was conducted to examine the correlation between depression and hopelessness levels in mothers of disabled children between the ages 5 and 7. A total of 126 mothers of children with disabilities was used in the study. They were obtained from the nursery schools of the
First Education Schools of the Ministry of Education or from private schools. In this study the Beck Depression Scale (Beck, Ward, Mendelson, Mock, & Erbaugh, 1961), Beck Hopelessness Scale (Beck, Lester, & Trexler, 1974) and a General Information Form (Ceylan & Aral, 2005) were
used for statistical analyses. The findings suggested a significant correlation between the depression and hopelessness levels of mothers of disabled children (p < .01).
BELIEFS AND ATTITUDES ABOUT TRANSRACIAL ADOPTION AMONG A SAMPLE OF SOUTH AFRICAN STUDENTS
Authors: Moos Aziza , Mwaba Kelvin
Published: April 2009

Transracial adoption, defined as the adoption of a child from a race that is different from that of the adoptive parent, has attracted interest among social scientists seeking to understand how the public views adoption. Studies conducted mostly in industrialized countries suggest that
most people approve of such adoption, believing it is a better alternative to out-of-home care. Those who are opposed believe that it risks damaging the racial or ethnic identity of the child. In South Africa, it is just over 10 years since the new democratic government repealed all previous
laws that prohibited mixing of races including interracial marriage and transracial adoption. In the present study we sought to understand South African students' beliefs and attitudes about transracial adoption. A sample of 72 mostly black undergraduate students was surveyed. The results
showed that most of the students approved of transracial adoption and believed that it promoted racial tolerance. Less than 5% believed that transracial adoption could lead to the loss of a child's culture. The results were interpreted as suggesting that young South Africans may
be committed to the vision of a multiracial nation.
A prediction of self-esteem and life satisfaction by social problem solving
Authors: Hamarta Erdal
Published: April 2009

The aim of this study was to determine whether or not social problem solving by university students predicts their self-esteem and life satisfaction. The survey model was adopted and the sample of the study consisted of 405 university students. The results of the study showed that self-esteem
and life satisfaction are positively correlated with positive problem orientation and rational problem solving; they are negatively correlated with negative problem orientation, impulsivity/carelessness, and avoidance styles. The results also showed that negative problem orientation, positive
problem orientation, and avoidance style significantly predicted self-esteem. In addition, rational problem solving, positive problem orientation, and avoidance style significantly predicted life satisfaction.
The transcriptional cascade associated with creatine kinase down-regulation and mitochondrial biogenesis in mice sarcoma
Authors: Bera Soumen , Ray Manju
Published: April 2009

The tissue-specific expressions of creatine kinase (CK) isoforms are regulated by the coordinated action of various transcription factors. The myogenic differentiation factor D (MyoD) family of proteins and the myocyte-specific enhancer binding factor 2 family of transcription factors are important in regulating the muscle-specific expression of cytosolic muscle-type CK (MCK) and mitochondrial CKs. As reported in some related studies, TNF-α mediated degradation of MyoD and myogenin mRNA may lead to severe muscle wasting and cachexia, which is characterized by a low transcript level of MCK and myosin heavy chain proteins. In our previous study, we reported on a complete loss of total CK activity and expression when sarcoma was induced in mouse skeletal muscle (Patra et al. FEBS J. 275 (2008) 3236–3247). This study aimed at investigating the transcriptional cascade of CK down-regulation in carcinogen-induced sarcoma in mouse muscle. Both CK deficiency and enhanced nitric oxide synthase (NOS) were known to augment mitochondrial biogenesis, so we also explored the activation of the transcriptional cascade of mitochondrial biogenesis in this cancer. We observed the activation of the TNF-α-mediated nitric oxide production pathway with NFκB activation and concomitant degradation of MyoD and myogenin mRNA. Exploration of mitochondrial biogenesis revealed high cytochrome c oxidase activity and mitochondrial DNA content in sarcoma. The PGC-related co-activator seems to have a major role in regulating mitochondrial biogenesis by upregulating nuclear respiratory factors and mitochondrial transcription factor A. From the above findings, it can be concluded that severe muscle degeneration leads to CK down-regulation in sarcoma, and that the stimulation of mitochondrial biogenesis indicated a scenario representing both CK deficiency and NOS overexpression on the one hand, and altered bioenergetic profiling on the other.
Maximum Entropy on Compact Groups
Authors: Harremoës Peter
Published: April 2009

In a compact group the Haar probability measure plays the role of uniform distribution. The entropy and rate distortion theory for this uniform distribution is studied. New results and simplified proofs on convergence of convolutions on compact groups are presented and they can be formulated as entropy increases to its maximum. Information theoretic techniques and Markov chains play a crucial role. The convergence results are also formulated via rate distortion functions. The rate of convergence is shown to be exponential.
Synthesis of New Naphtho[2,3-f]quinoxaline-2,7,12(1H)-trione and Anthra-9,10-quinone Dyes from Furan-2,3-diones
Authors: Üngören Şevket Hakan
Published: April 2009

Novel naphtho[2,3-f]quinoxaline-2,7,12(1H)-trione and anthra-9,10-quinone dyes were synthesized in good yield from furan-2,3-diones using 1,2-diaminoanthra-9,10-quinone and 1,4-diaminoanthra-9,10-quinone. The chromophores were characterized by molecular spectroscopy methods.
Role of the Heparan Sulfate Proteoglycan Syndecan-1 (CD138) in Delayed-Type Hypersensitivity
Authors: Masouleh Behzad Kharabi , Ten Dam Gerdy B. , Wild Martin K. , Seelige Ruth , van der Vlag Johan , Rops Angelique L. , Echtermeyer Frank G. , Vestweber Dietmar , van Kuppevelt Toin H. , Kiesel Ludwig , Götte Martin
Published: April 2009

The cell surface heparan sulfate proteoglycan syndecan-1 (CD138) modulates the activity of chemokines, cytokines, integrins, and other adhesion molecules which play important roles in the regulation of inflammation. We have previously shown that syndecan-1-deficient murine leukocytes display increased interactions with endothelial cells and increased diapedesis in vivo and in vitro. In this study, we demonstrate that syndecan-1 has an important function as a negative modulator in the murine contact allergy model of oxazolone-mediated delayed-type hypersensitivity (DTH). Following elicitation of the DTH response, syndecan-1-deficient mice showed an increase in leukocyte recruitment, resulting in an increased and prolonged edema formation. Expression of the cytokines TNF-α and IL-6 of the chemokines CCL5/RANTES and CCL-3/MIP-1α and of the adhesion molecule ICAM-1 were significantly increased in syndecan-1-deficient compared with wild-type mice. In wild-type mice, syndecan-1 mRNA and protein expression was reduced during the DTH response. The differentially increased adhesion of syndecan-1-deficient leukocytes to ICAM-1 was efficiently inhibited in vitro by CD18-blocking Abs, which emerges as one mechanistic explanation for the anti-inflammatory effects of syndecan-1. Collectively, our results show an important role of syndecan-1 in the contact DTH reaction, identifying syndecan-1 as a novel target in anti-inflammatory therapy.
Contribution of Adenosine A2B Receptors to Inflammatory Parameters of Experimental Colitis
Authors: Frick Julia-Stefanie , MacManus Christopher F. , Scully Melanie , Glover Louise E. , Eltzschig Holger K. , Colgan Sean P.
Published: April 2009

Inflammatory diseases influence tissue metabolism, significantly altering the profile of extracellular adenine nucleotides. A number of studies have suggested that adenosine (Ado) may function as an endogenously generated anti-inflammatory molecule. Given the central role of intestinal epithelial cells to the development of colitis, we hypothesized that specific Ado receptors would contribute to disease resolution in mucosal inflammation as modeled by dextran sodium sulfate (DSS) colitis. Initial profiling studies revealed that murine intestinal epithelial cells express predominantly the Ado A2B receptor (AA2BR) and to a lesser extent AA2AR. Guided by these results, we examined the contribution of AA2BR to colitis. Initial studies indicated that the severity of colitis was increased in Aa2br−/− mice relative to Aa2br+/+ controls, as reflected by increased weight loss, colonic shortening, and disease activity indices. Likewise, enteral administration of the selective AA2BR inhibitor PSB1115 to Aa2br+/+ mice resulted in a similar increase in severity of DSS colitis. Cytokine profiling of colonic tissue revealed specific deficiencies in IL-10 in Aa2br−/− mice relative to controls. Extensions of these findings in cultured human intestinal epithelial cells revealed that stable Ado analogs induce IL-10 mRNA and protein and that such increases can be blocked with PSB1115. Taken together, these studies indicate a central regulatory role for AA2BR-modulated IL-10 in the acute inflammatory phase of DSS colitis, thereby implicating AA2BR as an endogenously protective molecule expressed on intestinal epithelial cells.
Functional Blocking Monoclonal Antibodies against IL-12p40 Homodimer Inhibit Adoptive Transfer of Experimental Allergic Encephalomyelitis
Authors: Mondal Susanta , Roy Avik , Pahan Kalipada
Published: April 2009

IL-12p70 (p40:p35) and IL-23 (p40:p19) are bioactive cytokines and their role in experimental allergic encephalomyelitis (EAE), an animal model for multiple sclerosis, are becoming clear. On the other hand, the IL-12p40 homodimer (p402) was considered as an inactive or inhibitory molecule and its functions are poorly understood. To facilitate the studies on p402, we have recently generated neutralizing mAb against mouse p402. The present study demonstrates the effectiveness of p402 mAb in treating the disease process of relapsing-remitting EAE in female SJL/J mice. The p402 mAb ameliorated clinical symptoms and disease progression of EAE in recipient mice and suppressed the generation of encephalitogenic T cells in donor mice. Histological and blood-brain barrier (BBB) and blood-spinal cord barrier (BSB) permeability studies reveal that p402 mAb effectively inhibited the infiltration of mononuclear cells into brain and spinal cord and improved the integrity of BBB and BSB in EAE mice. Consequently, p402 mAb also suppressed the expression of proinflammatory molecules, normalized the expression of myelin genes, and blocked demyelination in the CNS of EAE mice. On the other hand, recombinant mouse p402 increased the infiltration of mononuclear cells into the CNS, enhanced the permeability through BBB and BSB, stimulated CNS expression of proinflammatory molecules, and aggravated the disease process of EAE. Taken together, our results suggest that p402 participates in the pathogenesis of EAE and that neutralization of p402 may be beneficial in multiple sclerosis patients.
A Protective Role for Dengue Virus-Specific CD8+ T Cells
Authors: Yauch Lauren E. , Zellweger Raphaël M. , Kotturi Maya F. , Qutubuddin Afrina , Sidney John , Peters Bjoern , Prestwood Tyler R. , Sette Alessandro , Shresta Sujan
Published: April 2009

Infection with one of the four serotypes of dengue virus (DENV1–4) can result in a range of clinical manifestations in humans, from dengue fever to the more serious dengue hemorrhagic fever/dengue shock syndrome. Although T cells have been implicated in the immunopathogenesis of secondary infections with heterologous DENV serotypes, the role of T cells in protection against DENV is unknown. In this study, we used a mouse-passaged DENV2 strain, S221, to investigate the role of CD8+ T cells in the immune response to primary DENV infection. S221 did not replicate well in wild-type mice, but did induce a CD8+ T cell response, whereas viral replication and a robust CD8+ T cell response were observed after infection of IFN-α/βR−/− mice. Depletion of CD8+ T cells from IFN-α/βR−/− mice before infection resulted in significantly higher viral loads compared with undepleted mice. Mapping the specificity of the CD8+ T cell response led to the identification of 12 epitopes derived from 6 of the 10 DENV proteins, with a similar immunodominance hierarchy observed in wild-type and IFN-α/βR−/− mice. DENV-specific CD8+ T cells produced IFN-γ, TNF-α, expressed cell surface CD107a, and exhibited cytotoxic activity in vivo. Finally, immunization with four of the immunodominant CD8+ T cell epitopes enhanced viral clearance. Collectively, our results reveal an important role for CD8+ T cells in the host defense against DENV and demonstrate that the anti-DENV CD8+ T cell response can be enhanced by immunization, providing rationale for designing DENV-specific vaccines that induce cell-mediated immunity.
A Novel and Critical Role for Tyrosine 663 in Platelet Endothelial Cell Adhesion Molecule-1 Trafficking and Transendothelial Migration
Authors: Dasgupta Bidisha , Dufour Eric , Mamdouh Zahra , Muller William A.
Published: April 2009

PECAM-1/CD31 is required for leukocyte transendothelial migration (TEM) under most inflammatory conditions. A critical pool of PECAM-1 resides in the lateral border recycling compartment (LBRC). During TEM, membrane from the LBRC is redirected to surround the leukocyte, and this targeted recycling per se is required for TEM. The cytoplasmic domain of PECAM-1 contains two tyrosine residues that have been implicated in PECAM-1 signaling in other cells but never examined in the context of TEM. We found that expression of PECAM-1 imparts on cells the ability to support TEM and that tyrosine 663 (but not tyrosine 686) is required. Furthermore, tyrosine 663 is required for PECAM-1 to efficiently enter and exit the LBRC. Most important, mutation of tyrosine 663 abolishes the ability of the endothelial cells to support targeted recycling of the LBRC. These data define a novel role for tyrosine 663 and suggest that it is part of a recognition motif for trafficking to and/or from the LBRC.
p53 Attenuates Lipopolysaccharide-Induced NF-κB Activation and Acute Lung Injury
Authors: Liu Gang , Park Young-Jun , Tsuruta Yuko , Lorne Emmanuel , Abraham Edward
Published: April 2009

The transcriptional factor p53 has primarily been characterized for its central role in the regulation of oncogenesis. A reciprocal relationship between the activities of p53 and NF-κB has been demonstrated in cancer cells, but there is little information concerning interactions between p53 and NF-κB in inflammatory processes. In this study, we found that neutrophils and macrophages lacking p53, i.e., p53−/−, have elevated responses to LPS stimulation compared with p53+/+ cells, producing greater amounts of proinflammatory cytokines, including TNF-α, IL-6, and MIP-2, and demonstrating enhanced NF-κB DNA-binding activity. p53−/− mice are more susceptible than are p53+/+ mice to LPS-induced acute lung injury (ALI). The enhanced response of p53−/− cells to LPS does not involve alterations in intracellular signaling events associated with TLR4 engagement, such as activation of MAPKs, phosphorylation of IκB-α or the p65 subunit of NF-κB, or IκB-α degradation. Culture of LPS-stimulated neutrophils and macrophages with nutlin-3a, a specific inducer of p53 stabilization, attenuated NF-κB DNA-binding activity and production of proinflammatory cytokines. Treatment of mice with nutlin-3a reduced the severity of LPS-induced ALI. These data demonstrate that p53 regulates NF-κB activity in inflammatory cells and suggest that modulation of p53 may have potential therapeutic benefits in acute inflammatory conditions, such as ALI.
MicroRNA-21 Is Up-Regulated in Allergic Airway Inflammation and Regulates IL-12p35 Expression
Authors: Lu Thomas X. , Munitz Ariel , Rothenberg Marc E.
Published: April 2009

Allergic airway inflammation is characterized by marked in situ changes in gene and protein expression, yet the role of microRNAs (miRNAs), a new family of key mRNA regulatory molecules, in this process has not yet been reported. Using a highly sensitive microarray-based approach, we identified 21 miRNAs with differential expression between doxycycline-induced lung-specific IL-13 transgenic mice (with allergic airway inflammation) and control mice. In particular, we observed overexpression of miR-21 and underexpression of miR-1 in the induced IL-13 transgenic mice compared with control mice. These findings were validated in two independent models of allergen-induced allergic airway inflammation and in IL-4 lung transgenic mice. Although IL-13-induced miR-21 expression was IL-13Rα1 dependent, allergen-induced miR-21 expression was mediated mainly independent of IL-13Rα1 and STAT6. Notably, predictive algorithms identified potential direct miR-21 targets among IL-13-regulated lung transcripts, such as IL-12p35 mRNA, which was decreased in IL-13 transgenic mice. Introduction of pre-miR-21 dose dependently inhibited cellular expression of a reporter vector harboring the 3′-untranslated region of IL-12p35. Moreover, mutating miR-21 binding sites in IL-12p35 3′-untranslated region abrogated miR-21-mediated repression. In summary, we have identified a miRNA signature in allergic airway inflammation, which includes miR-21 that modulates IL-12, a molecule germane to Th cell polarization.
Maintenance of Peripheral Tolerance through Controlled Tissue Homing of Antigen-Specific T Cells in K14-mOVA Mice
Authors: Bianchi Teresa , Pincus Laura B. , Wurbel Marc-André , Rich Benjamin E. , Kupper Thomas S. , Fuhlbrigge Robert C. , Boes Marianne
Published: April 2009

Immunological tolerance is crucial to avoid autoimmune and inflammatory diseases; however, the mechanisms involved are incompletely understood. To study peripheral tolerance to skin-associated Ags, we generated new transgenic mice expressing a membrane-bound form of OVA in skin under the human keratin 14 (K14) promoter (K14-mOVA mice). In contrast to other transgenic mice expressing similar self-Ags in skin, adoptive transfer of Ag-specific T cells does not induce inflammatory skin disease in our K14-mOVA mice. OVA-specific T cells transferred into K14-mOVA mice are activated in lymphoid tissues, undergo clonal expansion, and eventually acquire effector function. Importantly, these Ag-specific T cells selectively up-regulate expression of E-selectin ligand in cutaneous lymph nodes but not in mesenteric lymph nodes and spleen, demonstrating that expression of endogenous self-Ags in skin dictates imprinting of skin tissue homing in vivo. However, an additional inflammatory signal, here induced by tape stripping, is required in K14-mOVA mice to induce T cell migration to skin and development of inflammatory skin disease. Depletion of regulatory CD4+CD25+ T cells did not provoke homing of transferred T cells to skin under steady-state conditions, indicating that these cells are not the key regulators for inhibiting T cell homing in K14-mOVA mice. Both skin-derived and lymph node-resident CD8α+ dendritic cells are responsible for Ag presentation in vivo and induce tolerance to skin Ags, as we show by selective depletion of langerin+ and CD11c+ dendritic cells. Taken together, controlled skin homing of T cells is critical for the maintenance of peripheral immune tolerance to epidermal self-Ags.
Langerhans Cells Are Not Required for the CD8 T Cell Response to Epidermal Self-Antigens
Authors: Bursch Laura S. , Rich Benjamin E. , Hogquist Kristin A.
Published: April 2009

Langerhans cells (LC) are APC that reside at the barrier surfaces. Mice expressing an OVA peptide in the epidermis (K14-OVAp) were used to study CD8+ T cell responses to an epidermal self-Ag. Earlier results suggested that LC were the predominant APC, inducing a robust T cell response and autoimmunity. In this study, we used a whole protein model system, the K14-mOVA mouse, in which a transmembrane form of OVA was expressed in keratinocytes. In contrast to K14-OVAp mice, T cells in K14-mOVA mice were activated, but did not expand and instead died by apoptosis. Furthermore, in double-transgenic mice expressing both mOVA and OVAp, robust OT-I expansion occurred, indicating that tolerance to this Ag is not dominant and was due to lack of activating signals. We sought to identify the relevant APC in K14 mice using bone marrow chimeras and found that radioresistant cells (presumably LC) were able to cross-present the OVA Ag from keratinocytes to naive T cells in the lymph node. However, use of LC-deficient mice indicated that LC were not required for the expansion of OT-I in K14-OVAp or the deletion of OT-I in K14-mOVA mice. These data suggest that radioresistant non-LC present self-Ag in K14-OVAp mice and drive a robust CD8 T cell response.
HLA-DQ8 (DQB1*0302)-Restricted Th17 Cells Exacerbate Experimental Autoimmune Encephalomyelitis in HLA-DR3-Transgenic Mice
Authors: Mangalam Ashutosh , Luckey David , Basal Eati , Jackson Megan , Smart Michele , Rodriguez Moses , David Chella
Published: April 2009

Among all of the genetic factors associated with multiple sclerosis (MS) susceptibility, MHC class II molecules have the strongest association. Although a direct role of DR alleles in MS have been confirmed, it has been difficult to understand the role of DQ alleles in disease pathogenesis due to strong linkage disequilibrium with certain DR alleles. Population studies have indicated that DQ alleles may play a modulatory role in progression of MS. Using HLA class II transgenic (Tg) mice, we investigated gene complementation between DR and DQ genes in the disease process. Previously, using single Tg mice (expressing HLA-DR or DQ gene), we showed that PLP91–110 peptide induced experimental autoimmune encephalomyelitis (EAE) only in DR3.Aβ° mice, suggesting that DR3 (DRB1*0301) is a disease susceptibility gene in the context of PLP. We also showed that DQ6 protects development of EAE in DQ6/DR3 double Tg mice by production of anti-inflammatory IFN-γ. In this study, we investigated the ability of DQ8 to modulate disease in DR3/DQ8 double Tg mice. Introduction of DQ8 onto DR3 Tg mice led to higher disease incidence and increased disease severity on immunization with PLP91–110, indicating that DQ8 had an exacerbating effect on the development of EAE. Increased susceptibility in DR3/DQ8 Tg mice was due to increased production of proinflammatory cytokine IL-17 by DQ8-restricted T cells. HLA-DR3/DQ8 mice with EAE also demonstrated increased inflammation and demyelination in CNS as compared with single DR3 Tg mice. Thus double Tg mouse provides a novel model to study epistatic interactions between HLA class II molecules in inflammatory and demyelinating disease.
Induction of Airway Hyperreactivity by IL-25 Is Dependent on a Subset of Invariant NKT Cells Expressing IL-17RB
Authors: Stock Philippe , Lombardi Vincent , Kohlrautz Viola , Akbari Omid
Published: April 2009

IL-25 has been shown to induce Th2 responses and airway hyperreactivity (AHR) in mice, but the mechanism of action is not understood and it is unclear which cells mediate this disease. In this study we show that the receptor for IL-25, IL-17RB, is highly expressed on a subset of naive and activated CD4+ invariant NKT (iNKT) cells, but not on activated T cells. IL-17RB+ iNKT cells produced large amounts of Th2 cytokines that were substantially increased by IL-25 stimulation. Furthermore, IL-17RB+ iNKT cells were capable of restoring AHR in iNKT cell-deficient mice, whereas IL-17RB− iNKT cells failed to reconstitute AHR and lung inflammation. Finally, IL-17RB+ iNKT cells were detected in the lungs of wild-type mice, and induction of AHR by intranasal administration of IL-25 was significantly impaired in iNKT cell-deficient mice. Overall, our data suggest a critical role for iNKT cells in IL-25-mediated AHR. These results may lead to novel therapeutic approaches to target IL-17RB+ iNKT cells for the treatment of allergic asthma.