4,136 research outputs found
MitoTALENs: A general approach to reduce mutant mtDNA loads and restore oxidative phosphorylation function in mitochondrial diseases
We have designed mitochondrially targeted Transcription Activator-Like Effector Nucleases or mitoTALENs to cleave specific sequences in the mitochondrial DNA (mtDNA) with the goal of eliminating mtDNA carrying pathogenic point mutations. To test the generality of the approach we designed mitoTALENs to target two relatively common pathogenic mtDNA point mutations associated with mitochondrial diseases: the m.8344A>G tRNA^(Lys) gene mutation associated with Myoclonic Epilepsy with Ragged-Red Fibers (MERRF) and the m.13513G>A ND5 mutation associated with MELAS/Leigh Syndrome. Transmitochondrial cybrid cells harbouring the respective heteroplasmic mtDNA mutations were transfected with the respective mitoTALEN and analysed after different time periods. MitoTALENs efficiently reduced the levels of the targeted pathogenic mtDNAs in the respective cell lines. Functional assays showed that cells with heteroplasmic mutant mtDNA were able to recover respiratory capacity and oxidative phosphorylation enzymes activity after transfection with the mitoTALEN. To improve the design in the context of the low complexity of mtDNA, we designed shorter versions of the mitoTALEN specific for the MERRF m.8344A>G mutation. These shorter mitoTALENs also eliminated the mutant mtDNA. These reductions in size improve our ability to package these large sequences into viral vectors, bringing the use of these genetic tools closer to clinical trials
Estudo seccional revela um alto percentual de infecção assintomática por Plasmodium vivax em área do Rio Negro, Amazonas, Brasil
A parasitological, clinical, serological and molecular cross-sectional study carried out in a highly endemic malaria area of Rio Negro in the Amazon State, Brazil, revealed a high prevalence of asymptomatic Plasmodium vivax infection. A total of 109 persons from 25 families were studied in five villages. Ninety-nine inhabitants (90.8%) had at least one previous episode of malaria. Serology showed 85.7% and 46.9% of positivity when P. falciparum antigens and P. vivax MSP-1, respectively, were used. Twenty blood samples were PCR positive for P. vivax (20.4%) and no P. falciparum infection was evidenced by this technique. No individual presenting positive PCR reaction had clinical malaria during the survey neither in the six months before nor after, confirming that they were cases of asymptomatic infection. Only one 12 year old girl presented a positive thick blood smear for P. vivax. This is the first description of asymptomatic Plasmodium infection in this area studied.Um estudo seccional parasitológico, clínico, sorológico e molecular, realizado em uma área altamente endêmica para malária, no Rio Negro, Estado do Amazonas, revela alta prevalência de infecção assintomática por Plasmodium vivax. Um total de 109 pessoas de 25 famílias residentes em cinco comunidades do Rio Padauiri, afluente do Rio Negro, foram estudadas. Noventa por cento dos habitantes (90,8%) tinham tido pelo menos um episodio prévio de malária. A sorologia mostrou 85,7% e 46,9% de positividade quando antígenos de P. falciparum e P. vivax MSP-1, foram respectivamente usados. Vinte amostras de sangue submetidas ao PCR foram positivas para P. vivax (20,4%), entretanto, nenhuma foi positiva para o P. falciparum por esta técnica. Nenhum paciente com PCR positivo durante o inquérito e seis meses antes ou depois teve manifestações clínicas de malária, portanto, podemos afirmar que eram assintomáticos. Somente uma criança de 12 anos de idade teve gota espessa positiva para P. vivax. Esta é a primeira descrição de infecção assintomática por Plasmodium na área estudada
Pattern of humoral immune response to Plasmodium falciparum blood stages in individuals presenting different clinical expressions of malaria
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Background\ud
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The development of protective immunity against malaria is slow and to be maintained, it requires exposure to multiple antigenic variants of malaria parasites and age-associated maturation of the immune system. Evidence that the protective immunity is associated with different classes and subclasses of antibodies reveals the importance of considering the quality of the response. In this study, we have evaluated the humoral immune response against Plasmodium falciparum blood stages of individuals naturally exposed to malaria who live in endemic areas of Brazil in order to assess the prevalence of different specific isotypes and their association with different malaria clinical expressions.\ud
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Methods\ud
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Different isotypes against P. falciparum blood stages, IgG, IgG1, IgG2, IgG3, IgG4, IgM, IgE and IgA, were determined by ELISA. The results were based on the analysis of different clinical expressions of malaria (complicated, uncomplicated and asymptomatic) and factors related to prior malaria exposure such as age and the number of previous clinical malaria attacks. The occurrence of the H131 polymorphism of the FcγIIA receptor was also investigated in part of the studied population.\ud
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Results\ud
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The highest levels of IgG, IgG1, IgG2 and IgG3 antibodies were observed in individuals with asymptomatic and uncomplicated malaria, while highest levels of IgG4, IgE and IgM antibodies were predominant among individuals with complicated malaria. Individuals reporting more than five previous clinical malaria attacks presented a predominance of IgG1, IgG2 and IgG3 antibodies, while IgM, IgA and IgE antibodies predominated among individuals reporting five or less previous clinical malaria attacks. Among individuals with uncomplicated and asymptomatic malaria, there was a predominance of high-avidity IgG, IgG1, IgG2 antibodies and low-avidity IgG3 antibodies. The H131 polymorphism was found in 44.4% of the individuals, and the highest IgG2 levels were observed among asymptomatic individuals with this allele, suggesting the protective role of IgG2 in this population.\ud
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Conclusion\ud
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Together, the results suggest a differential regulation in the anti-P. falciparum antibody pattern in different clinical expressions of malaria and showed that even in unstable transmission areas, protective immunity against malaria can be observed, when the appropriated antibodies are produced.We would like to especially thank Dr. Cristóvão Luis Pitangueira Mangueira, Flávia Cristina Kinskowski and Milca Geane de Lamos Valim at the Central Laboratory of the Clinical Hospital for participating in the determination of the total IgE and IgA levels. This work was supported by FAPESP (process number 2001/04073-5) and Laboratório de Investigações Médicas do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (LIM-48/HCFMUSP)We would like to especially thank Dr. Cristóvão Luis Pitangueira Mangueira, Flávia Cristina Kinskowski and Milca Geane de Lamos Valim at the Central Laboratory of the Clinical Hospital for participating in the determination of the total IgE and IgA levels. This work was supported by FAPESP (process number 2001/040735) and Laboratório de Investigações Médicas do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (LIM48/HCFMUSP
Análise do conteúdo de artrópodes em livros didáticos de biologia do ensino médio e o perfil do professor: estudo de caso
Há décadas, o livro didático (LD) é tido como principal recurso de ensino e aprendizagem, do qual professores e alunos fazem uso, com ou sem erros factuais, conceituais e de conteúdo. O filo Arthropoda, além de compreender o maior grupo de metazoários, desperta interesse entre professores e alunos, devido ao convívio cotidiano. O objetivo deste trabalho foi o de realizar uma análise estrutural e qualitativa dos LDs de biologia utilizados no Ensino Médio em colégios da rede pública de ensino do município de Cascavel, PR, bem como do conteúdo específico do filo Arthropoda. Além disso, levantou-se o perfil do professor para uma possível correlação com a escolha do LD. Para a análise do livro, adaptou-se uma ficha de avaliação de manuais escolares, e para o levantamento do perfil aplicou-se um questionário semi-estruturado, abordando aspectos relacionados à formação, atuação, metodologia de ensino e opinião do professor sobre o LD. Verificou-se que ambos os livros analisados apresentam falhas referentes ao conteúdo e ilustrações, sendo mais evidentes em um dos livros e que há uma possível relação entre o perfil do professor e a escolha do LD
Attenuation of motor deficits by hydroethanolic extract of Poincianella pyramidalis in a Parkinson's disease model
The present study aimed to evaluate the possible neuroprotective effect of the hydroethanolic extract of Poincianella pyramidalis (EFIPp) (Tul.) L. P. Queiroz (Fabaceae), an endemic plant found in Northeastern Brazil, commonly used in folk medicine, on the motor deficits induced by repeated treatment with reserpine (RES) in rats. Adult male Wistar rats received 10 s.c. injections of 0.1 mg/kg RES or vehicle (VR), every 48 h, and daily i.p. injections daily of HEPp (25 mg/kg) or vehicle (VE). Throughout treatment, catalepsy behavior and oral movements were scored. After behavioral tests, superoxide dismutase (SOD) and catalase (CAT) activities were evaluated in the prefrontal cortex, hippocampus and striatum. RES treatment induced a progressive increase of catalepsy time in the treated group compared to control groups starting at day 15. RES also increased the number of vacuous chewing movements, tongue protrusions and duration of facial twitching. Treatment with HEPp attenuated the motor deficit in the catalepsy test and delayed the onset of oral movements induced by RES. No significant changes were observed in the antioxidant assay. Taken together, these results show a beneficial effect of HEPp on motor deficits induced by reserpine, suggesting a neuroprotective effect in a rat model of PD.Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)Fundação de Apoio a Pesquisa e a Inovação Tecnologica do Estado de Sergipe (FAPITEC)Pro-reitoria de Pesquisa da Universidade Federal de Sergipe (POSGRAP/UFS)Univ Fed Sergipe, Dept Physiol, Sao Cristovao, SE, BrazilUniv Massachusetts, Neurosci & Behav Program, Amherst, MA 01003 USAMinist Educ, CAPES Fdn, BR-70040020 Brasilia, DF, BrazilUniv Fed Sao Paulo, Dept Biosci, Santos, SP, BrazilUniv Fed Sao Paulo, Dept Pharmacol, Sao Paulo, SP, BrazilUniv Fed Sergipe, Dept Biosci, Itabaiana, SE, BrazilUniv Fed Sao Paulo, Dept Biosci, Santos, SP, BrazilUniv Fed Sao Paulo, Dept Pharmacol, Sao Paulo, SP, BrazilWeb of Scienc
Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV
The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8 TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum
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