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1.
Micron ; 182: 103637, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38688142

RESUMO

The ultrastructure of snake sperm has received substantial attention primarily because snakes exhibit considerable variability in reproductive characteristics between species, with a wide range of mating systems and reproductive behaviors. Variability of sperm morphology among snake species may be associated with the reproductive strategies of each taxon, such as competition or sperm storage. We provide a detailed description of the sperm ultrastructure of nine snake species (Anilius scytale, Tropidophis paucisquamis, Bothrops jararaca, Oxyrhopus guibei, Dipsas mikanii, Micrurus corallinus, Xenopholis scalaris, Acrochordus javanicus, and Cylindrophis ruffus) and compared this with sperm data from the literature for the following taxa: Liotyphlops beui, Amerotyphlops reticulatus, Trilepida koppesi, Anilios waitii, Anilios endoterus, Aspidites melanochephalus, Boa constrictor amarali, Corallus hortulana, Epicrates cenchria, Boa constrictor occidentalis, Eryx jayakari, Micrurus corallinus, Micrurus surinamensis, Micrurus frontalis, Micrurus altirostris, Oxyuranus microlepidotus, Bothrops alternatus, Bothrops diporus, Crotalus durissus, Agkistrodon contortrix, Vipera aspis, Boiga irregularis, Zamenis schrenckii, Zamenis scalaris, Stegonotus cuculatus, Nerodia sipedon, Liodytes pygaea, and Myrrophis chinensis. We found twelve polymorphic characters in the ultrastructure of sperm among the described snakes. Our work supports the importance of ultrastructural analysis of sperm morphology to understand snake reproduction, and provides sperm-derived morphological characters for phylogenetic analysis.


Assuntos
Serpentes , Espermatozoides , Animais , Masculino , Espermatozoides/ultraestrutura , Serpentes/anatomia & histologia , Microscopia Eletrônica de Transmissão/métodos
2.
J Dent Res ; 97(5): 580-588, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29439598

RESUMO

Diabetes mellitus increases periodontitis and pathogenicity of the oral microbiome. To further understand mechanisms through which diabetes affects periodontitis, we examined its impact on periodontal ligament fibroblasts in vivo and in vitro. Periodontitis was induced by inoculation of Porphyromonas gingivalis and Fusobacterium nucleatum in normoglycemic and diabetic mice. Diabetes, induced by multiple low-dose injections of streptozotocin increased osteoclast numbers and recruitment of neutrophils to the periodontal ligament, which could be accounted for by increased CXC motif chemokine 2 (CXCL2) and receptor activator of nuclear factor kappa B ligand (RANKL) expression by these cells. Diabetes also stimulated a significant increase in nuclear factor kappa B (NF-κB) expression and activation in periodontal ligament (PDL) fibroblasts. Surprisingly, we found that PDL fibroblasts express a 2.3-kb regulatory unit of Col1α1 (collagen type 1, alpha 1) promoter typical of osteoblasts. Diabetes-enhanced CXCL2 and RANKL expression in PDL fibroblasts was rescued in transgenic mice with lineage-specific NF-κB inhibition controlled by this regulatory element. In vitro, high glucose increased NF-κB transcriptional activity, NF-κB nuclear localization, and RANKL expression in PDL fibroblasts, which was reduced by NF-κB inhibition. Thus, diabetes induces changes in PDL fibroblast gene expression that can enhance neutrophil recruitment and bone resorption, which may be explained by high glucose-induced NF-κB activation. Furthermore, PDL fibroblasts express a regulatory element in vivo that is typical of committed osteoblasts.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Fibroblastos/metabolismo , NF-kappa B/metabolismo , Ligamento Periodontal/metabolismo , Animais , Quimiocina CXCL2/metabolismo , Diabetes Mellitus Experimental/complicações , Feminino , Imunofluorescência , Gengiva/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Periodontite/diagnóstico por imagem , Periodontite/etiologia , Periodontite/metabolismo , Ligante RANK/metabolismo , Microtomografia por Raio-X
3.
J Periodontal Res ; 52(4): 734-744, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28256038

RESUMO

BACKGROUND AND OBJECTIVE: The potential benefits of statins in modulating periodontal disease is supported by in vitro and clinical studies showing statins can induce a lower expression of proinflammatory cytokines and matrix metalloproteinases. The aim of this study was to evaluate the effects of rosuvastatin (ST) on ligature-induced periodontitis in spontaneously hypertensive rats (SHR). MATERIAL AND METHODS: Fifty-four adult male rats were divided into three groups: SHR-C, SHR-L and SHR-L-ST (C, control; L, ligature groups). In the SHR-L-ST group, animals were treated with daily 2 mg/kg ST administration. In L groups, a ligature remained around mandibular first molars for 10 d. Each group was divided for killing at 10 or 21 d postoperatively. Microtomographic and histometric analyses were performed. Osteoclastogenesis was evaluated by tartrate-resistant acid phosphatase assay and gene expression of 84 proinflammatory mediators by polymerase chain reaction array. RESULTS: The SHR-L-ST group showed reduced bone loss and attachment loss in comparison with the SHR-L group at both 10 and 21 d postoperatively (p < 0.05). ST decreased the amount of tartrate-resistant acid phosphatase-positive cells compared with the SHR-L group at both 10 and 21 d (p < 0.05). The SHR-L-ST group presented 14 genes differentially expressed when compared with SHR-L group, featuring a downregulated gene profile at 10 d. CONCLUSION: Statin therapy may promote a protective effect against alveolar bone and connective tissue attachment losses attributable to periodontitis in hypertensive rats through inflammatory gene profile modulation.


Assuntos
Periodontite/tratamento farmacológico , Ratos Endogâmicos SHR , Rosuvastatina Cálcica/farmacologia , Animais , Biomarcadores/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Expressão Gênica , Ligadura , Masculino , Mandíbula , Osteoclastos/efeitos dos fármacos , Periodontite/diagnóstico por imagem , Reação em Cadeia da Polimerase , Ratos , Microtomografia por Raio-X
4.
Rev. bras. plantas med ; 18(1,supl.1): 367-372, 2016. tab
Artigo em Português | LILACS | ID: lil-782972

RESUMO

RESUMO As doenças pós-colheita do mamão são as principais responsáveis pelas perdas que ocorrem durante esse processo. A antracnose é uma doença causada pelo fungo Colletotrichum gloeosporioides. Esse patógeno tem a capacidade de se estabelecer no fruto imaturo, permanecendo em estado latente até que as condições se tornem favoráveis ao seu desenvolvimento. O presente estudo teve como objetivo determinar o efeito fungistático dos óleos essenciais sobre o fungo C.gloeosporioides. Os experimentos foram realizados no laboratório de Fitossanidade da Universidade Estadual de Mato Grosso do Sul, Unidade Universitária de Cassilândia, foram três etapas, quais sejam: I efeito dos óleos essenciais sobre a germinação de conídios, II- ação in vitro dos óleos sobre micélios fúngicos e III- efeito dos óleos essenciais sobre o fungo em frutos do mamoeiro. Para as três fases o delineamento experimental utilizado foi inteiramente casualizado, em esquema fatorial 6 X 5, (óleos essenciais de alecrim, menta, capim-limão, anis, árvore-chá e canela) e cinco concentrações (0 μL, 10 μL, 30 μL, 50 μL, 100 μL), com 5 repetições. A germinação de conídios foi afetada drasticamente pelos óleos de menta e árvore-chá. O efeito fungitóxico do óleo de menta foi confirmado nos experimentos subsequentes, nos quais essa substância na concentração de 100 µL inibiu completamente o crescimento micelial invivo e in vitro do fungo C. gloeosporioides. Os óleos de alecrim e árvore-chá também afetam o crescimento micelial in vivo e in vitro desse fungo, embora em menor intensidade.


ABSTRACT Post-harvest papaya diseases are primarily responsible for the losses suffered during this process. Anthracnose is a disease caused by the Colletotrichum gloeosporioides fungus. This pathogen has the ability to settle in the immature fruit, remaining dormant until conditions become favorable for its development. The purpose of this study was to determine the fungicidal effect of essential oils on the C. gloeosporioides fungus. The experiments were undertaken in the Plant Health laboratory of the State University of Mato Grosso do Sul, at the University Unit of Cassilandia, where an evaluation was performed in three stages, namely: I) the effect of essential oils on spore germination, II) the in vitro action of oils on mycelium fungi, and III) the effect of essential oils on the fungus in papaya fruit. For the three phases, the experimental design was completely randomized in a 6 x 5 factorial arrangement (essential oils of rosemary, mint, lemongrass, anise, tea tree, and cinnamon) and five concentrations (0 uL, 10 uL, 30 uL, 50 uL, 100 uL) with five replications. The spore germination was drastically affected by the mint and tea tree oils. The fungitoxic effect of peppermint oil was confirmed in subsequent experiments in which this substance at a concentration of 100 uL completely inhibited the mycelial in vivo and in vitro growth of the C. gloeosporioides fungus. The rosemary and tea tree oils also affect the mycelial in vivo and in vitro growth of this fungus, albeit to a lesser degree.


Assuntos
Técnicas In Vitro/métodos , Óleos Voláteis/análise , Carica/classificação , Fungos/isolamento & purificação
5.
Rev. bras. plantas med ; 17(2): 254-261, Apr-Jun/2015. tab, graf
Artigo em Português | LILACS | ID: lil-746136

RESUMO

RESUMO: No Brasil existem várias doenças fúngicas que acometem a bananeira. Destas, pode-se citar a antracnose, responsável por grandes prejuízos à cultura, cujo agente causal é o fungo Colletotrichum musae. A principal forma de controle dessa enfermidade é através da aplicação de fungicidas a base de tiabendazol ou tiofanato metílico. Esse manejo, embora eficiente, favorece o desenvolvimento de resistência do patógeno, causa danos ao ambiente e ao produtor, deixando ainda resíduos nos frutos. Esses fatores têm favorecido a busca por substâncias alternativas com capacidade de controlar o fungo e que não sejam nocivas ao ambiente e, principalmente, que sejam seguras ao consumidor final. Dentre as opções, surge o interesse pelo uso de certos óleos essenciais e da própolis, ambos conhecidos por possuírem propriedades fungicidas. O presente trabalho foi desenvolvido com o objetivo de determinar o potencial fungitóxico "in vitro" da própolis e dos óleos essenciais de palmarosa (Cymbopogon martinii), de teatree (Melaleuca alternifolia), de cravo (Eugenia caryophyllata), e de eucalipto (Corymbia citriodora), sobre Colletotrichum musae. O desenvolvimento experimental consistiu em adicionar inóculos fúngicos de 5 mm, obtidos a partir de colônias puras, ao meio de cultura BDA (batata-dextrose-ágar) acrescido das referidas substâncias em diferentes concentrações (0, 25, 50, 75, 100 e 125 µL/L). Paralelo aos tratamentos realizou-se teste com o fungicida padrão para comparações das médias. A eficiência das substâncias sobre o fungo foi determinada através das avaliações do crescimento micelial das colônias (média de duas medidas diametralmente opostas). Os valores de crescimento micelial obtidos foram utilizados também para o cálculo do índice de velocidade de crescimento micelial. O delineamento experimental utilizado foi inteiramente casualizado em esquema fatorial 5 x 6 + 1, (cinco substâncias em seis concentrações + fungicida), com cinco repetições. Os óleos de tea tree, cravo e palmarosa foram eficientes no controle do fungo Colletotrichum musae não diferindo do fungicida a partir da dose de 50 µL/L em todas as avaliações, apresentando potencial para controle em cultivos orgânicos ou em sistemas de manejo integrado.


ABSTRACT: In Brazil there are several fungi that cause diseases on banana plants. These include the "anthracnose", which is responsible for major crop losses and whose causative agent is the fungus Colletotrichum musae. The main way to control this disease is through the application of fungicides based on thiabendazole and thiophanate-methyl. Although this management is effective, it favors the development of pathogen resistance, which causes damage to the environment and producer and also leaves residues in fruits. These factors have encouraged the search for alternative substances to control the fungus and that are not harmful to the environment and particularly to the final consumer. Among the options, there is interest in the use of essential oils and propolis, both known to have antifungal activity. The present work was developed with the objective of determining the potential of propolis and essential oils of palmarosa (Cymbopogon martinii), tea tree (Melaleuca alternifolia), clove (Eugenia caryophyllata) and eucalyptus (Corymbia citriodora) in the in vitro control of the fungus Colletotrichum musae. The experimental development consisted in adding 5 mm fungal inoculants, obtained from pure colonies, in PDA culture (potato-dextrose-agar) plus the aforementioned substances in different concentrations (0, 25, 50, 75, 100 and 125 µL/L). At the same time as these treatments, we carried out a test with the fungicide to compare the averages. The efficiency of the substances on the fungus was determined through evaluations of the mycelial growth of the colonies (average of two diametrically opposed measures). The values of mycelial growth obtained were also used for the calculation of the speed index of the mycelial growth. The experimental design was completely randomized in 5 x 6 + 1 (5 substances in 6 concentrations + fungicide) factorial design, with 5 repetitions. The tea tree, clove and palmarosa oils were efficient in the control of the fungus Colletotrichum musae, which can be used as a control option in organic crops or in integrated management systems.


Assuntos
Própole/análise , Óleos Voláteis/farmacologia , Colletotrichum/classificação , Musa/classificação , Microbiologia , /prevenção & controle
6.
Rev. bras. plantas med ; 16(1): 54-61, 2014. graf, tab
Artigo em Português | LILACS | ID: lil-703722

RESUMO

Devido às poucas informações sobre as práticas de cultivo do capim-limão (Cymbopogon citratus, DC.) objetivou-se avaliar o efeito de lâminas de irrigação sobre: a produção de biomassa, o rendimento e composição do óleo essencial. O experimento foi instalado em ambiente protegido para possibilitar o controle das lâminas de irrigação e avaliar a viabilidade para situações em que as condições climáticas normais sejam inadequadas. O delineamento experimental foi em blocos inteiramente casualizados com cinco tratamentos e três repetições. Os dados foram submetidos à análise de variância pelo tese F e as médias comparadas pelo teste de Tukey a 5% de probabilidade. Na etapa um, os tratamentos consistiram da aplicação de lâminas referentes a 50%, 75%, 100%, 125% da evapotranspiração da cultura (ETc), irrigando duas vezes por semana e de 100% da evapotranspiração da cultura (ETc), irrigando uma vez por semana, sendo denominados de T1, T2, T3, T4 e T5, respectivamente. Na etapa dois, os tratamentos consistiram da aplicação de lâminas referentes a 50%, 75%, 100%, 125% da ETc irrigando uma vez por semana e de 100% da ETc, irrigando a cada 14 dias, sendo denominados de T6, T7, T8, T9 e T10 respectivamente. O corte do capim-limão foi realizado após 60 dias do início dos tratamentos. Avaliou-se a altura de plantas, o número de perfilhos por touceira, a massa seca da parte aérea, o rendimento e a composição do óleo essencial. O T5, caracterizado por estresse hídrico e intervalo de irrigação moderado, foi o que apresentou a maior produção de matéria seca, maior produtividade do capim-limão e maior estimativa da produtividade de óleo essencial e maior concentração de citral, na primeira etapa. Na etapa dois, o T6, correspondente ao estresse hídrico crescente e acentuado, foi o que apresentou maior estimativa da produtividade de óleo essencial. De acordo com os resultados observados, não foi possível definir a melhor lâmina, porém, concluiu-se que uma única irrigação semanal, para as condições estudadas neste experimento promoveu o melhor resultado.


The aim of this work was to evaluate the effect of different irrigation depths on biomass production, yield and composition of lemongrass (Cymbopogon citratus)essential oil, because of poor information on cultivation practices. The experiment was set up in a protected environment to control irrigation and also to evaluate situations in which the normal climatic conditions are inadequate. A complete randomized block design was incorporated with five treatments and three replications, and averages were compared using the Tukey's test at 5% probability. In phase one, the treatments consisted of irrigation depths relating to 50%, 75%, 100%, 125% of crop evapotranspiration (ETc), irrigating twice a week, and irrigating only once a week for a sample supplied with 100% of the crop evapotranspiration (ETc); these were labeled T1, T2, T3, T4 and T5, respectively. In phase two, the treatments consisted of depths of 50%, 75%, 100%, 125% of the ETc, irrigating once a week, and another with 100% of the ETc, irrigating every 14 days, which were denominated T6, T7, T8, T9 and T10, respectively. Harvest of the lemon grass was done after 60 days of treatment. Plant height, number of tillers per plant, dry mass of the shoots, yield and composition of essential oil were evaluated. Treatment T5, characterized by water stress and a moderate irrigation interval, presented the highest dry matter production, lemongrass productivity, estimate of essential oil productivity and concentration of citral in the first phase. In phase two of this work, T6,characterized by a sharp increaseof water stress, presented the greatest estimate of essential oil productivity. According to the results observed, we could not define an optimal irrigation depth; however, we concluded that a single irrigation per week for the conditions of this experiment provided the best result.


Assuntos
Óleos Voláteis/farmacologia , Cymbopogon/crescimento & desenvolvimento , Eficiência/classificação , Desidratação , Irrigação Agrícola
7.
Genet Mol Res ; 10(4): 2664-70, 2011 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-22057962

RESUMO

Smith-Magenis syndrome (SMS) is a complex congenital anomaly characterized by craniofacial anomalies, neurological and behavioral disorders. SMS is caused by a deletion in region 17p11.2, which includes the RAI1 gene (90% of cases), or by point mutation in the RAI1 gene (10% of cases). Laboratory diagnosis is through cytogenetic analysis by GTG banding and molecular cytogenetic analysis by FISH. We carried out an active search for patients in Associations of Parents and Friends of Exceptional Children (APAE) of São Paulo and genetic centers in Brazil. Forty-eight patients were screened for mental retardation, craniofacial abnormalities and stereotyped behavior with a diagnosis of SMS. In seven of them, chromosome banding at high resolution demonstrated chromosome 17p11.2 deletions, confirmed by FISH. We also made a meta-analysis of 165 cases reported between 1982 and 2010 to compare with the clinical data of our sample. We demonstrated differences between the frequencies of clinical signs among the cases reported and seven Brazilian cases of this study, such as dental anomalies, strabismus, ear infections, deep hoarse voice, hearing loss, and cardiac defects. Although the gold standard for diagnosis of SMS is FISH, we found that the GTG banding technique developed to evaluate chromosome 17 can be used for the SMS diagnosis in areas where the FISH technique is not available.


Assuntos
Bandeamento Cromossômico/métodos , Deleção Cromossômica , Cromossomos Humanos Par 17/genética , Mutação Puntual , Síndrome de Smith-Magenis , Fatores de Transcrição/genética , Adolescente , Brasil , Criança , Feminino , Humanos , Masculino , Síndrome de Smith-Magenis/diagnóstico , Síndrome de Smith-Magenis/genética , Síndrome de Smith-Magenis/patologia , Transativadores
8.
Braz. j. microbiol ; 38(1): 131-134, Jan.-Mar. 2007. tab
Artigo em Inglês | LILACS | ID: lil-449382

RESUMO

The aim of this study was to investigate the presence of antibiotic resistant Staphylococcus aureus strains in fish stalls and in hands and nasal and oral cavities of fish handlers of the Mucuripe Fish Market, Fortaleza, Ceará, Brazil. All S. aureus isolates were resistant to Ampicillin and 44 percent were multi-drug resistant.


O objetivo da pesquisa foi investigar a presença de Staphylococcus aureus resistente a antibióticos nos boxes de venda de peixe e nas mãos e cavidades nasal e oral de manipuladores de pescado da Feira de Pescado do Mucuripe, Fortaleza, Ceará. Todas as cepas isoladas foram resistentes à ampicilina e 44 por cento apresentaram multiresistência.


Assuntos
Resistência a Ampicilina , Produtos Pesqueiros , Técnicas In Vitro , Staphylococcus aureus , Amostras de Alimentos , Métodos
9.
Rev Inst Med Trop Sao Paulo ; 43(5): 263-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11696848

RESUMO

Over the last 30 years, a number of Vibrio species found in the aquatic environment have been indicated as cause of disease in human beings. Vibrio vulnificus is an emergent pathogen, an invasive and lethal marine bacterium related to wound infection and held accountable for gastroenteritis and primary septicemia. It occurs quite frequently in marine organisms, mainly in mollusks. This study aimed at isolating and identifying strains of V. vulnificus based upon the analysis of twenty samples of seabob shrimp, Xiphopenaeus kroyeri (Heller), purchased at the Mucuripe fish market (Fortaleza, Brazil). TCBS agar was used to isolate suspect strains. Seven of twenty-nine strains isolated from six different samples were confirmed as such by means of biochemical evidence and thus submitted to biological assays to determine their virulence. The susceptibility of the V. vulnificus strains to a number of antibiotics was tested. None of the V. vulnificus strains showed signs of virulence during a 24-hour observation period, possibly due to the shedding of the capsules by the cells. As to the results of the antimicrobial susceptibility tests, the seven above-mentioned V. vulnificus strains were found to be sensitive to nitrofurantoin (NT), ciprofloxacin (CIP), gentamicin (GN) and chloramphenicol (CO) and resistant to clindamycin (CI), penicillin (PN) and ampicillin (AP).


Assuntos
Decápodes/microbiologia , Frutos do Mar/microbiologia , Vibrio/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Testes de Sensibilidade Microbiana , Vibrio/classificação , Vibrio/efeitos dos fármacos
10.
Cytobios ; 106 Suppl 2: 203-16, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11545447

RESUMO

Spermiogenesis in the bufonid Melanophryniscus cambaraensis was analysed ultrastructurally. The nucleus of spermatids undergoes morphological modifications divided into five distinct stages based on chromatin condensation. The acrosomal vesicle differentiates into an acrosome and a subacrosomal cone, which cap the anterior region of the nucleus. The spermatozoa consist of the head with a nucleus and acrosomal complex and the tail, with an axoneme, an axial rod and an undulating membrane. The participation of several carbohydrate moieties during this differentiation process was detected using various gold-labelled lectins.


Assuntos
Bufonidae/fisiologia , Espermátides/citologia , Espermatogênese/fisiologia , Animais , Carboidratos/análise , Diferenciação Celular , Glicoconjugados/análise , Histocitoquímica , Lectinas , Masculino , Microscopia Eletrônica , Cabeça do Espermatozoide/química , Cabeça do Espermatozoide/ultraestrutura , Cauda do Espermatozoide/química , Cauda do Espermatozoide/ultraestrutura , Espermátides/química , Espermátides/ultraestrutura , Espermatozoides/química , Espermatozoides/citologia , Espermatozoides/ultraestrutura
11.
Tissue Cell ; 31(3): 308-17, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18627861

RESUMO

A detailed description of the sperm ultrastructure of Tropidurus semitaeniatus and T. torquatus is provided. Mature spermatozoa of T. semitaeniatus and T. torquatus are filiform and characterized by: apical portion of acrosome depressed; perforatorium single; epinuclear lucent zone well developed; midpiece short; mitochondria columnar; midpiece with three sets of alternating ring structures and mitochondria (rs1/m1, rs2/m2, rs3/m3); nuclear shoulders rounded; nucleus elongate; fibres 3 and 8 enlarged; and fibrous sheath in midpiece. Spermatozoa ofTropidurus are unusual in possessing a unilateral electron-lucent ridge at the surface of the acrosome and an epinuclear electron-lucent zone. The two species are very similar, differing in details such as degree of acrosome flattening, presence of bulging at nuclear base, and arrangement of microtubules in the endpiece. Comparisons between Tropiduridae and other families of iguanian lizards are made.

12.
Comp Biochem Physiol B ; 88(3): 977-81, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-2827953

RESUMO

1. Hydroxysteroid oxidoreductases have been partially purified from the cytosol fraction (105,000 g supernatant) of liver from a fresh-water turtle (Podocnemis expansa) and a sea-water turtle (Chelonia mydas mydas) by precipitation with ammonium sulphate (AS, 10-80% saturation). 2. The following enzymes were detected (substrates in brackets): 3 alpha-hydroxysteroid oxidoreductase (androsterone), 3 beta-hydroxysteroid oxidoreductase (DHEA) and 17 beta-hydroxysteroid oxidoreductase (testosterone, oestradiol-17 beta). NAD as well as NADP were effective as cofactors. 3. In fresh-water turtle, highest activities of the 3 alpha-enzyme were measured in the 20% AS fraction (cofactor NAD), of the 3 beta-enzyme in the 60% AS fraction (cofactor NAD) and of the 17 beta-enzyme in the 40% AS fraction (cofactor NADP). 4. In sea-water turtle, highest activities were observed for all three enzymes in the 60% AS fraction. 5. Generally, enzyme activities were higher in sea-water turtles than in fresh-water turtles. The most active enzyme in both turtles was found to be the 3 alpha-hydroxysteroid oxidoreductase, followed by the 17 beta- and the 3 beta-hydroxysteroid oxidoreductases.


Assuntos
Hidroxiesteroide Desidrogenases/metabolismo , Fígado/enzimologia , Tartarugas/metabolismo , 17-Hidroxiesteroide Desidrogenases/metabolismo , 3-Hidroxiesteroide Desidrogenases/metabolismo , 3-alfa-Hidroxiesteroide Desidrogenase (B-Específica) , Animais , Radioisótopos de Carbono , Citosol/enzimologia , Estradiol Desidrogenases/metabolismo , Feminino , Cinética , Masculino , Especificidade da Espécie
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