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Papers by Marcel Frajblat

A experimentacao animal foi determinante na evolucao da medicina e das ciencias biomedicas. Apesa... more A experimentacao animal foi determinante na evolucao da medicina e das ciencias biomedicas. Apesar desta importância, ate meados do seculo XX, estes animais estiveram em um segundo plano dentro do contexto cientifico. Apenas recentemente, percebeu-se a influencia do modelo animal e seu bem-estar nos resultados de um experimento. Como decorrencia surge a Ciencia em Animais de Laboratorio, cujo foco principal de estudo e o proprio animal e como este deve ser produzido e manipulado. Esta ciencia engloba uma serie de areas e serve de base para todas as outras ciencias biomedicas e incluem entre outras: sanidade, genetica, reproducao, bem-estar, instalacoes, etica e educacao. No Brasil, a partir dos anos 70 institutos de pesquisa e Universidades iniciaram uma producao mais controlada de animais com edificacoes construidas especificamente com este objetivo. Recentemente com a aprovacao da lei 11.794/2008 (Lei Arouca), primeira lei brasileira a regulamentar a experimentacao animal, foi ini...

Reproductive technologies have a fundamental role in biomedical research. Through them, new anima... more Reproductive technologies have a fundamental role in biomedical research. Through them, new animal models are produced and preserved safely. The production of genetically modified animals directly involves the use of embryos, their manipulation and transference to recipient females. Once a new genetically modified lineage has been produced, the best way to preserve it is by cryopreservation of sperm or embryos. A new technology for manipulating and modifying the mouse genome has been developed in recent years. The CRISPR / Cas9 system made the production of these animals faster, more effective and at a lower cost than traditional techniques. This technology will boost the worldwide mutant animal production project for each of the approximately 25,000 genes present in the mouse. It will also allow the production of models with double or triple mutation and in animals with different genetic backgrounds. This presentation will address the importance of reproductive techniques in this f...

Anais da Academia Brasileira de Ciências

Pathogenic microbial detection and control in laboratory animal facilities is essential to guaran... more Pathogenic microbial detection and control in laboratory animal facilities is essential to guarantee animal welfare, data validity and reproducibility. Helicobacter spp. are known to affect mice health, what may interfere with experimental outcomes. This study aimed to screen for Helicobacter spp. in mice from animal facilities in Rio de Janeiro, Brazil using a PCR-based method. Primers designed to specifi cally identify Helicobacter spp. were used to amplify feces or intestine DNA extracted of mice from four different animal facilities. The expected 375 base pairs (bp) amplicon was purifi ed, sequenced and a similarity of 95% was observed when compared to deposited sequences of H. hepaticus and H. bilis. In our screening, Helicobacter spp. was detected in ~59% of fecal and ~70% of intestine samples. Our study is the fi rst to screen for Helicobacter spp. in mouse facilities of a Rio de Janeiro University using a low cost, rapid molecular diagnostic test. Although Helicobacter spp. screening is not mandatory according to Brazilian animal welfare regulation it is recommended by institutional animal health monitoring programs guidelines worldwide, including ARRIVE, AAALAC and FELASA.

Revista De Etologia, Jun 1, 2011

Ciencia E Cultura, Jun 1, 2008

Revista De Etologia, Jun 1, 2011

A adequação do ambiente físico quanto aos hábitos da espécie em relação ao bem-estar animal e o r... more A adequação do ambiente físico quanto aos hábitos da espécie em relação ao bem-estar animal e o refinamento das pesquisas, ultimamente vem ganhando importância investigativa. Com o objetivo de avaliar o comportamento de ratos alojados em caixas de diferentes cores, utilizaram-se 48 animais machos com 3 meses de idade divididos em seis grupos, sendo que três grupos foram alojados em caixas brancas e outros três em caixas pretas, durante 4 semanas. Empregando-se o labirinto em cruz elevado (LCE), os resultados mostraram maior tempo de permanência nos braços fechados dos animais alojados nas caixas brancas. No teste do campo aberto (CA), houve maior ambulação do grupo mantido em caixas pretas, e na esquiva inibitória, os dados indicaram um aumento significativo no tempo de permanência na plataforma do grupo alojado em caixas pretas. Assim, os animais alojados em gaiolas de cor preta apresentaram maior tendência exploratória (menor ansiedade) e melhor aprendizado. Palavras-chave: Comportamento animal. Alojamento. Ratos Wistar. Evaluation of the behavior of rats housed in boxes of different colors. Lately, the adequacy of a physical ambient to the specie's habits relating to their well being and refined researches is getting important for researchers. With the aim of evaluate the behavior of rats housed in boxes of different colors, it was used 48 male animals, with 3 months of age, divided in 6 groups, three groups in white boxes and the other three in black boxes, for 4 weeks. Observing on the elevated plus maze, the results showed that the animals from white boxes stayed more time in the closed arms. On the open field test, there was more walking of the group kept in Black boxes, and on the inhibitory avoidance, data indicated a significant increase on the time spent on the platform by the group housed in the black boxes. Thus, the animal housed in Black cages have shown a greater exploratory tendency (decreased anxiety), and better learning.

Journal of animal …, 2002

Acta Scientiae Veterinariae, 2010

The importance of mice as animal model for research has promoted the surge of many strains with i... more The importance of mice as animal model for research has promoted the surge of many strains with important characteristics which need to be preserved. Embryo ...

Jornal brasileiro de reprodução assistida, 2015

This study aimed to assess the efficiency, in terms of recovered motile spermatozoa with normal m... more This study aimed to assess the efficiency, in terms of recovered motile spermatozoa with normal morphology, of three sperm selection techniques: migration- sedimentation (SS), swim-up from fresh semen (SF), and swim-up from washed (SL) sperm. Samples from 20 normozoospermic men were divided into three equal aliquots and processed in parallel. SS was performed in a Jondet tube, using 1 ml of semen and 2.5 ml of Human Tubal Fluid medium (HTF+10% Synthetic Serum Supplement, Irvine, USA). For SF, 1 ml of HTF was layered over 1 ml of fresh semen (SF). For SL, 1 ml of sperm was first centrifuged (300 g, 10 min) and the pellet resuspended in 1 ml of HTF; a second layer of HTF was placed on top. Migration time was 1h (SF and SL) and 1h30' for SS at 37°C. After migration, 200 μl were removed from the top layer (SF, SL) and from the central cone (SS). Concentration, morphology and motility were determined. Recovery rates were 25% for SS, 10.1% for SF and 4.5% for SL. SS recovery rate was ...

A experimentacao animal foi determinante na evolucao da medicina e das ciencias biomedicas. Apesa... more A experimentacao animal foi determinante na evolucao da medicina e das ciencias biomedicas. Apesar desta importância, ate meados do seculo XX, estes animais estiveram em um segundo plano dentro do contexto cientifico. Apenas recentemente, percebeu-se a influencia do modelo animal e seu bem-estar nos resultados de um experimento. Como decorrencia surge a Ciencia em Animais de Laboratorio, cujo foco principal de estudo e o proprio animal e como este deve ser produzido e manipulado. Esta ciencia engloba uma serie de areas e serve de base para todas as outras ciencias biomedicas e incluem entre outras: sanidade, genetica, reproducao, bem-estar, instalacoes, etica e educacao. No Brasil, a partir dos anos 70 institutos de pesquisa e Universidades iniciaram uma producao mais controlada de animais com edificacoes construidas especificamente com este objetivo. Recentemente com a aprovacao da lei 11.794/2008 (Lei Arouca), primeira lei brasileira a regulamentar a experimentacao animal, foi ini...

Reproductive technologies have a fundamental role in biomedical research. Through them, new anima... more Reproductive technologies have a fundamental role in biomedical research. Through them, new animal models are produced and preserved safely. The production of genetically modified animals directly involves the use of embryos, their manipulation and transference to recipient females. Once a new genetically modified lineage has been produced, the best way to preserve it is by cryopreservation of sperm or embryos. A new technology for manipulating and modifying the mouse genome has been developed in recent years. The CRISPR / Cas9 system made the production of these animals faster, more effective and at a lower cost than traditional techniques. This technology will boost the worldwide mutant animal production project for each of the approximately 25,000 genes present in the mouse. It will also allow the production of models with double or triple mutation and in animals with different genetic backgrounds. This presentation will address the importance of reproductive techniques in this f...

Anais da Academia Brasileira de Ciências

Pathogenic microbial detection and control in laboratory animal facilities is essential to guaran... more Pathogenic microbial detection and control in laboratory animal facilities is essential to guarantee animal welfare, data validity and reproducibility. Helicobacter spp. are known to affect mice health, what may interfere with experimental outcomes. This study aimed to screen for Helicobacter spp. in mice from animal facilities in Rio de Janeiro, Brazil using a PCR-based method. Primers designed to specifi cally identify Helicobacter spp. were used to amplify feces or intestine DNA extracted of mice from four different animal facilities. The expected 375 base pairs (bp) amplicon was purifi ed, sequenced and a similarity of 95% was observed when compared to deposited sequences of H. hepaticus and H. bilis. In our screening, Helicobacter spp. was detected in ~59% of fecal and ~70% of intestine samples. Our study is the fi rst to screen for Helicobacter spp. in mouse facilities of a Rio de Janeiro University using a low cost, rapid molecular diagnostic test. Although Helicobacter spp. screening is not mandatory according to Brazilian animal welfare regulation it is recommended by institutional animal health monitoring programs guidelines worldwide, including ARRIVE, AAALAC and FELASA.

Revista De Etologia, Jun 1, 2011

Ciencia E Cultura, Jun 1, 2008

Revista De Etologia, Jun 1, 2011

A adequação do ambiente físico quanto aos hábitos da espécie em relação ao bem-estar animal e o r... more A adequação do ambiente físico quanto aos hábitos da espécie em relação ao bem-estar animal e o refinamento das pesquisas, ultimamente vem ganhando importância investigativa. Com o objetivo de avaliar o comportamento de ratos alojados em caixas de diferentes cores, utilizaram-se 48 animais machos com 3 meses de idade divididos em seis grupos, sendo que três grupos foram alojados em caixas brancas e outros três em caixas pretas, durante 4 semanas. Empregando-se o labirinto em cruz elevado (LCE), os resultados mostraram maior tempo de permanência nos braços fechados dos animais alojados nas caixas brancas. No teste do campo aberto (CA), houve maior ambulação do grupo mantido em caixas pretas, e na esquiva inibitória, os dados indicaram um aumento significativo no tempo de permanência na plataforma do grupo alojado em caixas pretas. Assim, os animais alojados em gaiolas de cor preta apresentaram maior tendência exploratória (menor ansiedade) e melhor aprendizado. Palavras-chave: Comportamento animal. Alojamento. Ratos Wistar. Evaluation of the behavior of rats housed in boxes of different colors. Lately, the adequacy of a physical ambient to the specie's habits relating to their well being and refined researches is getting important for researchers. With the aim of evaluate the behavior of rats housed in boxes of different colors, it was used 48 male animals, with 3 months of age, divided in 6 groups, three groups in white boxes and the other three in black boxes, for 4 weeks. Observing on the elevated plus maze, the results showed that the animals from white boxes stayed more time in the closed arms. On the open field test, there was more walking of the group kept in Black boxes, and on the inhibitory avoidance, data indicated a significant increase on the time spent on the platform by the group housed in the black boxes. Thus, the animal housed in Black cages have shown a greater exploratory tendency (decreased anxiety), and better learning.

Journal of animal …, 2002

Acta Scientiae Veterinariae, 2010

The importance of mice as animal model for research has promoted the surge of many strains with i... more The importance of mice as animal model for research has promoted the surge of many strains with important characteristics which need to be preserved. Embryo ...

Jornal brasileiro de reprodução assistida, 2015

This study aimed to assess the efficiency, in terms of recovered motile spermatozoa with normal m... more This study aimed to assess the efficiency, in terms of recovered motile spermatozoa with normal morphology, of three sperm selection techniques: migration- sedimentation (SS), swim-up from fresh semen (SF), and swim-up from washed (SL) sperm. Samples from 20 normozoospermic men were divided into three equal aliquots and processed in parallel. SS was performed in a Jondet tube, using 1 ml of semen and 2.5 ml of Human Tubal Fluid medium (HTF+10% Synthetic Serum Supplement, Irvine, USA). For SF, 1 ml of HTF was layered over 1 ml of fresh semen (SF). For SL, 1 ml of sperm was first centrifuged (300 g, 10 min) and the pellet resuspended in 1 ml of HTF; a second layer of HTF was placed on top. Migration time was 1h (SF and SL) and 1h30' for SS at 37°C. After migration, 200 μl were removed from the top layer (SF, SL) and from the central cone (SS). Concentration, morphology and motility were determined. Recovery rates were 25% for SS, 10.1% for SF and 4.5% for SL. SS recovery rate was ...