Showing papers by "Fernando Ferreira published in 2004"

Type-A Arabidopsis response regulators are partially redundant negative regulators of cytokinin signaling.

Abstract: Type-A Arabidopsis (Arabidopsis thaliana) response regulators (ARRs) are a family of 10 genes that are rapidly induced by cytokinin and are highly similar to bacterial two-component response regulators. We have isolated T-DNA insertions in six of the type-A ARRs and constructed multiple insertional mutants, including the arr3,4,5,6,8,9 hextuple mutant. Single arr mutants were indistinguishable from the wild type in various cytokinin assays; double and higher order arr mutants showed progressively increasing sensitivity to cytokinin, indicating functional overlap among type-A ARRs and that these genes act as negative regulators of cytokinin responses. The induction of cytokinin primary response genes was amplified in arr mutants, indicating that the primary response to cytokinin is affected. Spatial patterns of ARR gene expression were consistent with partially redundant function of these genes in cytokinin signaling. The arr mutants show altered red light sensitivity, suggesting a general involvement of type-A ARRs in light signal transduction. Further, morphological phenotypes of some arr mutants suggest complex regulatory interactions and gene-specific functions among family members.

Epidemiologia da Leptospirose em animais silvestres na Fundação Parque Zoológico de São Paulo

Abstract: This study was aimed to achieve a better comprehension of the epidemiological aspects of leptospirosis in the Fundacao Parque Zoologico de Sao Paulo. From 1996 to 1999, blood samples were collected from 302 wild animals that were submitted to the Veterinary Division of the zoo for routine procedures. Positive Microscopic Aglutination Test were obtained from them 59 animals were positiv (19,5%) . The most frequent sorovars were copenhageni ( 15/59 = 25.4%), pomona (13/59 = 22%) and castellonis (10/59 = 16.9%). According to the orders and families of examined animals, the most frequent serovars were: Order Primate : copenhageni (13/25 = 52%), castellonis (5/25 = 20%) e grippotyphosa (2/25 = 8%). Family Felidae pomona (12/17 = 70.5%), icterohaemorrhagiae (2/17=11.7%) e grippotyphosa (1/17 = 5.8%). Family Cervidae : mini (1/1 = 100%). Family Bovidae : copenhageni (2/3 = 66.6%), pomona (1/3 = 33.3%). Order Rodentia : castellonis (2/3 = 66.6%). Family Macropodidae : sentot (1/1 = 100%). Family Girafidae : castellonis (1/1 = 100%). Free living specimens of the Muridae ( Rattus norvegicus ) and Didelphidae ( Didelphis marsupialis) families were also examined for Microscopic Aglutination Test and bacteriologic culture. Positive serologycal and bacteriologycal tests for Icterohaemorrhagiae serogrup were found in rodents, such as rats (3/7 = 42.8%) and opossum 2/5 = 40%). These strongly suggest that free-living rodents play na important role in the leptospirosis transmition inside the Zoo. Two specific areas, Extra Sector 1 and Feline Alley were considered critical due to the major proportion of seropositives animals. The possible reasons and these findings were sugestive for the profilatical procidures for the control of the Leptospirosis at the Sao Paulo Zoo were discussed.

Estimate of the owned canine and feline populations in urban area in Brazil

Abstract: OBJETIVO: Dada a importância do conhecimento acerca da populacao de caes e gatos domiciliados para o adequado planejamento e avaliacao das acoes de controle da raiva em areas urbanas, propoe-se a utilizacao de um valor preciso de estimativa dessas populacoes com base em indicadores populacionais humanos. METODOS: Foi calculada a razao entre as populacoes humana e animal (canina e felina) por meio de inspecoes domiciliares, no Municipio de Taboao da Serra, SP. O municipio foi dividido em duas areas homogeneas distintas socioeconomicamente, de acordo com o algoritmo da media k, de modo a permitir a comparacao das razoes homem:animal (cao e gato) das areas homogeneas. RESULTADOS: A razao entre a populacao humana e a populacao canina foi 5,14 e a entre a humana e a felina foi 30,57. Nao foi observada diferenca significativa ao comparar-se as razoes entre as populacoes humana e animal das areas homogeneas. CONCLUSOES: A adocao de uma metodologia de estimativa populacional canina e felina domiciliada, baseada em indicadores populacionais humanos, e a mais indicada e facilmente exequivel quando comparada ao censo canino.

Epidemiologia da Leptospirose em animais silvestres na Fundação Parque Zoológico de São Paulo Epidemiology of the Leptospirosis in wild animals at the Fundação Parque Zoológico de São Paulo

Abstract: This study was aimed to achieve a better comprehension of theepidemiological aspects of leptospirosis in the Fundacao ParqueZoologico de Sao Paulo. From 1996 to 1999, blood samples were collectedfrom 302 wild animals that were submitted to the Veterinary Division ofthe zoo for routine procedures. P ositive Microscopic Aglutination Testwere obtained from them 59 animals were positiv (19,5%) . The mostfrequent sorovars were copenhageni ( 15/59 = 25.4%), pomona (13/59= 22%) and castellonis (10/59 = 16.9%). According to the orders andfamilies of examined animals, the most frequent serovars were: OrderPrimate : copenhageni (13/25 = 52%), castellonis (5/25 = 20%) egrippotyphosa (2/25 = 8%). Family Felidae pomona (12/17 = 70.5%),icterohaemorrhagiae (2/17=11.7%) e grippotyphosa (1/17 = 5.8%).Family Cervidae : mini (1/1 = 100%). Family Bovidae : copenhageni (2/3 = 66.6%), pomona (1/3 = 33.3%). Order Rodentia : castellonis (2/3 =66.6%). Family Macropodidae : sentot (1/1 = 100%). Family Girafidae :castellonis (1/1 = 100%). Free living specimens of the Muridae (