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1.
Int J Syst Evol Microbiol ; 51(Pt 3): 751-758, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11411694

RESUMO

In order to reconstruct the evolution of euglenid flagellates, euglenozoan SSU rDNA data have been used to investigate phylogenetic relationships with a focus on osmotrophic taxa and especially on the Rhabdomonadales. The dataset consisting of the SSU rDNAs of osmotrophic, phagotrophic and phototrophic taxa was used in parsimony, maximum-likelihood and distance analyses. Five genera make up the Rhabdomonadales, all of them osmotrophic: Gyropaigne, Menoidium, Parmidium, Rhabdomonas and Rhabdospira. According to our analyses they form a strongly supported monophyletic assemblage which is characterized by a low sequence divergence compared to the euglenids in general. Closest relatives are the members of the osmotrophic genus Distigma. All primary osmotrophic species constitute a larger monophyletic group with the phototrophic euglenids and the phagotroph Peranema trichophorum. The combination of three rhabdomonadalian species Rhabdomonas gibba, Rhabdomonas spiralis and Rhabdospira spiralis with nearly identical SSU rDNA sequences is strongly recommended. The phagotroph Petalomonas cantuscygni branches at the bottom of the euglenid subtree with significantly weaker support. The inter-relationship of the three distinct euglenozoan taxa (euglenids, kinetoplastids and diplonemids) could not be convincingly resolved by this study.


Assuntos
DNA Ribossômico/genética , Euglênidos/classificação , Euglênidos/genética , Filogenia , Animais , DNA de Protozoário/genética , Euglena/classificação , Euglena/genética , Euglena gracilis/classificação , Euglena gracilis/genética , Variação Genética , RNA de Protozoário/genética , RNA Ribossômico/genética
2.
Protist ; 149(3): 265-76, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23194638

RESUMO

The Cryptophyta comprise photoautotrophic protists with complex plastids which harbor a remnant eukaryotic nucleus (nucleomorph) and a few heterotrophic taxa which either lack a plastid (Goniomonas) or contain a complex plastid devoid of pigments (Ieucoplast; Chilomonas). To resolve the phylogenetic relationships between photosynthetic, leucoplast-containing and aplastidial taxa, we determined complete nuclear-encoded SSU rRNA-sequences from 12 cryptophyte taxa representing the genera Cryptomonas, Chilomonas, Rhodomonas, Chroomonas, Hemiselmis, Proteomonas and Teleaulax and, as an outgroup taxon, Cyanoptyche gloeocystis (Glaucocystophyta). Phylogenetic analyses of SSU rRNA sequences from a total of 24 cryptophyte taxa rooted with 4 glaucocystophyte taxa using distance, parsimony and likelihood methods as well as LogDet transformations invariably position the aplastidial genus Goniomonas as a sister taxon to a monophyletic lineage consisting of all plastid containing cryptophytes including Chilomonas. Among the plastid-containing taxa, we identify six major clades each supported by high bootstrap values: clade I (Cryptomonas and Chilomonas), clade II (Rhodomonas, Pyrenomonas, Rhinomonas and Storeatula), clade III (Guillardia and the 'unidentified cryptophyte' strain CCMP 325), clade IV (Teleaulax and Geminigera), clade V (Proteomonas) and clade VI (Hemiselmis, Chroomonas and Komma). Clade I (Cryptomonas and Chilomonas) represents a sister group to clades II-VI which together form a monophyletic lineage; the phylogenetic relationships between clades II-VI remain largely unresolved. Chilomonas is positioned within the Cryptomonas clade and thus presumably evolved from a photosynthetic taxon of this genus. In our analysis the characters blue and red pigmentation do not correspond with a basal subdivision of the phylum, thus rejecting this character for higher-level classification of cryptophytes. However, different spectroscopic subtypes of phycoerythrin (PE I-III) and phycocyanin (PC II-IV) represent informative characters at a lower taxonomic level. Phycocyanin types are confined to the later diverging clade VI and within Hemiselmis, a species with phycocyanin is monophyletic with two species containing phycoerythrin. This supports previous molecular studies which demonstrated that the ß subunit of all cryptophyte biliproteins, regardless of spectroscopic type, is phylogenetically derived from the red algal ß-phycoerythrin gene family, therefore the cryptophyte phycocyanins presumably originated by chromophore replacement from phycoerythrin. Our phylogenetic analysis does not support a previous suggestion that the aplastidial cryptophyte Goniomonas evolved from an ancestor containing a complex cryptomonadtype plastid by nucleomorph and plastid loss.

3.
Biomed Biochim Acta ; 45(8): 1021-8, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3778431

RESUMO

Hooded rats of the Long-Evans strain with bilateral symmetric lesions of the nucleus reticularis pontis oralis (RPO) displayed locomotor hyperactivity in the open field (OF) compared with their preoperative values. Their locomotor velocity and their climbing rate were significantly enhanced. Habituation in the OF was significantly weakened. The lesioned rats were unable to acquire any active avoidance responses in a Y-maze or a jump test. They were unable to correctly perform preoperatively learned avoidance responses and could not relearn the tasks. Reaction times to the conditioned stimulus increased and more often the rats escaped only after the onset of the punishment; even their escape responses were instable. The lesioned rats were neurologically inconspicuous. One can assume that the RPO participates in a functional system for control and recall of learned (not inborn) programs.


Assuntos
Comportamento Animal , Formação Reticular/fisiologia , Animais , Aprendizagem da Esquiva , Eletrochoque , Comportamento Alimentar , Lateralidade Funcional , Habituação Psicofisiológica , Masculino , Atividade Motora , Ratos , Reflexo
7.
Stat Med ; 3(2): 173-84, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6463454

RESUMO

Three techniques for disease time-space clustering analysis, those of Knox, Mantel and Ederer-Myers-Mantel, were applied to simulated data so as to study their sensitivities. The simulated data corresponded to three alternative non-null models for the distribution, transmission and development of Hodgkin's disease (HD) which were formulated in accordance with the results of published studies. The results indicate that the three techniques may not be sufficiently sensitive to the clustering in a real data set of HD cases. Therefore, the inconclusive results obtained to date with regard to clustering of HD may be related to the low power of the statistical techniques employed.


Assuntos
Doença de Hodgkin/epidemiologia , Estatística como Assunto , Doença de Hodgkin/transmissão , Humanos , Israel , Probabilidade , Conglomerados Espaço-Temporais
8.
Am J Ind Med ; 4(1-2): 309-28, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6132552

RESUMO

Population monitoring of birth defects provides a means for detecting relative changes in their frequency. Many varied systems have been developed throughout the world since the thalidomide tragedy of the early 1960s. Although it is difficult to pinpoint specific teratogenic agents based on rises in rates of a particular defect or a constellation of defects, monitoring systems can provide clues for hypothesis testing in epidemiological investigations. International coordination of efforts in this area resulted in the founding of the International Clearinghouse for Birth Defects Monitoring Systems (ICBDMS) in 1974. In this paper we will describe the functions and basic requirements of monitoring systems in general, and look at the development and activities of the ICBDMS. A review of known and suspected environmental teratogenic agents (eg, chemical, habitual, biological, physical, and nutritional) is also presented.


Assuntos
Anormalidades Congênitas/etiologia , Anormalidades Induzidas por Medicamentos/epidemiologia , Anormalidades Induzidas por Radiação/epidemiologia , Anestésicos/toxicidade , Anticonvulsivantes/toxicidade , Antieméticos/toxicidade , Antituberculosos/toxicidade , Infecções Bacterianas/complicações , Anormalidades Congênitas/epidemiologia , Feminino , Deficiência de Ácido Fólico/complicações , Hormônios Esteroides Gonadais/toxicidade , Herpesvirus Humano 3/patogenicidade , Antagonistas dos Receptores Histamínicos H1/toxicidade , Humanos , Imunização/efeitos adversos , Praguicidas/toxicidade , Gravidez , Vírus da Rubéola/patogenicidade
10.
Med Microbiol Immunol ; 166(1-4): 249-54, 1978 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-723788

RESUMO

An influenza surveillance program developed and conducted in three districts in Israel during winter 1976--77, was based mainly on morbidity data in the general population, corroborated by sero-epidemiologic surveys on selected groups. This information was supplemented by data on mortality organized according to specific age groups. During the period under study, similar results were observed in each of the three districts surveyed. Two successive waves of influenza were recorded: an early wave due to B/Hong Kong/5/72 followed by an A/Victoria/3/75 outbreak. Both waves were of moderate extent, with the highest frequency of clinical influenza occurring in the youngest group, age 0--14 years. The age-specific mortality rates were highest and rather similar in the extreme age groups 65+ and 0. The search of A/New Jersey/8/76 antibody revealed a considerable proportion of positives with a higher titer in the older age groups. A special serologic survey among Yemenite Jews over 50 years of age, who immigrated to Israel in 1949, showed that the 1918 influenza pandemic also reached that isolated country. The surveillance program provided an early warning system as well as a rather accurate measurement of influenza impact in Israel.


Assuntos
Surtos de Doenças/epidemiologia , Inquéritos Epidemiológicos , Influenza Humana/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Anticorpos Antivirais/análise , Criança , Pré-Escolar , Humanos , Lactente , Influenza Humana/imunologia , Influenza Humana/mortalidade , Israel , Judeus , Pessoa de Meia-Idade , Orthomyxoviridae/imunologia , Iêmen/etnologia
11.
Dev Biol Stand ; 39: 437-42, 1977.
Artigo em Inglês | MEDLINE | ID: mdl-604128

RESUMO

The main objectives of the monitoring were: (1) to define the prevalent virus involved in influenza activity: (2) to determine the time of its occurrence; and (3) to evaluate its extent and impact. A sudden rise in the frequency of visits associated with acute respiratory conditions in the age group 0-14 to the emergency rooms of 14 hospitals throughout the country, correlated well with the start of influenza B/Hong Kong activity; this was simultaneously attested by two different laboratories. The later and sporadic occurrence of influenza A/Victoria activity did not affect the usual trend observed in the frequency of visits to emergency rooms. An age group stratified serologic follow-up pointed to a progressively increasing rate of influenza B infection up to the age group 15-24. A crude morbidity rate of 13-18% was recorded during influenza B outbreaks in several agricultural settlements. The percentage distribution of cases was about 15,21, 26 and 37 in the age groups 0-4, 5-9, 10-14 and 15+, respectively. The mortality associated with influenza B and influenza A activity did not exceed the expected rate.


Assuntos
Influenza Humana/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Criança , Pré-Escolar , Surtos de Doenças , Hospitais Gerais , Humanos , Lactente , Vírus da Influenza A/imunologia , Vírus da Influenza A/isolamento & purificação , Influenza Humana/microbiologia , Israel , Pessoa de Meia-Idade , Vigilância da População , Doenças Respiratórias/epidemiologia , Doenças Respiratórias/mortalidade , Estações do Ano
12.
Infection ; 5(2): 71-5, 1977.
Artigo em Inglês | MEDLINE | ID: mdl-881264

RESUMO

Two inactivated influenza-virus vaccines were tested and compared in three army training units in Israel. The serological responses to the vaccines and the side-effects were assessed. The vaccines contained the influenza strains which were prevalent in 1974: A2/Port Chalmers/1/73 and B/Hong Kong/8/73. One of the vaccines also contained A2/England/42/72. Both vaccines caused a more than three-fold rise in geometric mean titers against influenza A strains, and about a twofold rise in geometric mean titers against influenza B/Hong Kong/5/73. Approximately 75%-80% of the vaccinees acquired protective hemagglutination-inhibition antibody titers against influenza A strains, while less than 30% acquired protective titers against B strains. In general, there were no significant differences between the serological responses to the two vaccines. More than 50% of the vaccinees experienced at least one systemic side-effect (50.3% with one vaccine and 61.0% with the other). The average number of side-effects per person was between 1.78 and 2.11. However, these side-effects were generally of short duration and caused minimal disability. On the whole, the two vaccines did not differ significantly with regard to the side-effects they caused.


Assuntos
Formação de Anticorpos , Vacinas contra Influenza/efeitos adversos , Influenza Humana/prevenção & controle , Medicina Militar , Vacinação , Humanos , Vacinas contra Influenza/administração & dosagem , Influenza Humana/imunologia , Israel
16.
Minerva Med ; 66(45): 2189-99, 1975 Jun 20.
Artigo em Italiano | MEDLINE | ID: mdl-1170527

RESUMO

Experience with thalidomide and German measles contracted during pregnancy has focused attention on the question of birth defects. It is suggested that good reasons exist for the carrying out epidemiological investigations to establish the true incidence and geographical and social distribution of such deformities, and hence their possibly "environmental" origin at least in some instances. Such investigations would supplement research into experimental teratology. The advantages, disadvantages and limitations of retrospective and prospective investigations are discussed. A detailed account is given of a prospective survey in progress in Israel. Reference is also made to a similar survey being launched in some Italian cities with the aid of the CNR.


Assuntos
Anormalidades Congênitas/epidemiologia , Anormalidades Induzidas por Medicamentos/epidemiologia , Anormalidades Múltiplas/epidemiologia , Osso e Ossos/anormalidades , Sistema Nervoso Central/anormalidades , Anormalidades Congênitas/classificação , Consanguinidade , Anormalidades do Sistema Digestório , Exposição Ambiental , Métodos Epidemiológicos , Etnicidade , Feminino , Cardiopatias Congênitas/epidemiologia , Humanos , Israel , Articulações/anormalidades , Troca Materno-Fetal , Prontuários Médicos , Gravidez , Estudos Prospectivos , Doenças Respiratórias/congênito , Estudos Retrospectivos , Anormalidades Urogenitais
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