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1.
Sci Total Environ ; 712: 136427, 2020 Apr 10.
Article de Anglais | MEDLINE | ID: mdl-31935548

RÉSUMÉ

Inhaled radon from groundwater used for domestic purposes is one of the sources of natural radioactivity into indoor air. Due to uranium-bearing minerals occurrences, hydrogeochemical conditions, tectonic structures, and hydraulic circuits, the radon pathway from rocks to groundwater is quite unpredictable. High radon potential from bedrocks is not always associated with high radon levels in groundwater. Besides, inhaled radon from domestic use may also increase the exposure toindoor radon levels. This innovative methodology using hydrogeochemical conditions and groundwater flow transport was used for radon predictions in the underground to ensure safe drinking water ingestion and inhalation. This innovative radon prediction methodology is based on classic hydrogeochemical analyses (Eh-pH, Piper, Schöeller and Gibb's diagrams) and multivariate statistical analyses (Principal Component Analysis and Pearson's correlation). High dissolution of major ions does not imply high radon mobilization from rocks to groundwater. The travel time was estimated to developed a flow transport of contaminated groundwater. Radiological results show that of the 25 sampled springs, five of them contained radon concentrations above the Portuguese imposed limit (222Rn = 500 Bq·L-1), and 16 of them with values above the WHO recommended limit (222Rn = 100 Bq·L-1). Overall, this new approach of radon prediction showed that uranium enrichment in rocks at ideal hydrochemical conditions and emanation coefficient, and shallow circuits, are responsible for radon increasing in drinking water. The proposed approach allow to predict the areas with high radon potential groundwaters, being a tool to be used by water planners and policy makers for corrective and preventive measures in shallow groundwater flows. To safeguard clean water within the predefined deadline of Sustainable Development Goals (2030) and to ensure human health in compliance with WHO guidelines for safe drinking water, should be established priority water protection policies to reduced radon in this contaminated springs (n = 16).


Sujet(s)
Eau de boisson/composition chimique , Nappe phréatique , Humains , Contrôle des radiations , Radon , Polluants radioactifs de l'eau
2.
Ultrason Imaging ; 41(1): 17-34, 2019 01.
Article de Anglais | MEDLINE | ID: mdl-30239291

RÉSUMÉ

We describe the concept of a new imaging modality based on the tracking and dynamic modeling of local intensity changes (ICs) observed in conventional ultrasound images collected during a medium-temperature change. We computed the pixel-by-pixel IC from averaged B-mode images that exhibited different behaviors with varying temperature resulting from changes in the speed of sound, which consequently induce changes in the backscattered energy. Moreover, for each pixel, a first-order polynomial model was adjusted to the different temperature-dependent ICs. The representation of the polynomial angular parameter in 2D pixel space was used to obtain a parametric image. The results obtained by simulations and with real B-mode images indicated that this new ultrasound imaging modality was able to enhance the contrast and highlight structures that were poorly visible or even undetected in conventional images. A temperature change of 3°C was found to be sufficient to generate appropriate images with the proposed method. In addition, if a temperature change of 6°C was considered, the thermal dose, measured as the cumulative number of equivalent minutes at 43°C (CEM43°C), was 2.4 CEM43°C, which is a value that is considered safe according to the literature. We provide a proof-of-concept of a new imaging modality that opens new opportunities for the enhancement of ultrasound images and consequently contributes to improvements in ultrasound-based diagnoses. Our approach is based on images returned by commercial ultrasound scanners. Therefore, it can be implemented in any ultrasound system and is independent of specific ultrasound hardware and software data acquisition characteristics.


Sujet(s)
Amélioration d'image/méthodes , Traitement d'image par ordinateur/méthodes , Température , Échographie/méthodes , Algorithmes , Animaux , Simulation numérique , Études de faisabilité , Modèles animaux , Modèles statistiques , Suidae
3.
Ecotoxicol Environ Saf ; 133: 164-75, 2016 Nov.
Article de Anglais | MEDLINE | ID: mdl-27448957

RÉSUMÉ

At Vila Pouca de Aguiar area, northern Portugal, crops out a post-tectonic Variscan granite pluton, related with the Régua-Vila Real-Verín fault zone, comprising three types of biotite granites. Among these granites, PSG granite yield the highest average contents of U, probably due to its enrichment in accessory U-bearing minerals such as zircon. In the proximity of faults and joints, these granites are often affected by different degrees of hydrothermal alteration, forming reddish altered rocks, commonly known as "episyenites". These altered rocks are probably associated to the occurrence of hydrothermal processes, which led to uranium enrichment in the most advanced stages of episyenitization. In these granites, both average gamma absorbed dose rates in outdoor and indoor air are higher than those of the world average. Furthermore, even in the worst usage scenario, all these granites can be used as a building material, since their annual effective doses are similar to the limit defined by the European Commission. The geometric mean of radon activity of 91 dwellings located at the Vila Pouca de Aguiar pluton is 568Bqm(-3), exceeding that of other northern Portuguese granites. Measurements carried out during a winter season, indicate that 62.6% of the analysed dwellings yield higher indoor radon average values than the Portuguese legislation limit (400Bqm(-3)), and annual effective doses due higher than the world's average value (1.2mSvy(-1)). The interaction of geogenic, architectural and anthropogenic features is crucial to explain the variance in the geometric mean of radon activity of dwellings from Vila Pouca de Aguiar pluton, but the role of geologic faults is probably the most important decisive factor to increase the indoor radon concentration in dwellings. Hence, the development of awareness campaigns in order to inform population about the incurred radiological risks to radon exposure are highly recommended for this specific area.


Sujet(s)
Polluants atmosphériques radioactifs/analyse , Pollution de l'air intérieur/analyse , Matériaux de construction , Radon/analyse , Silice , Silicates d'aluminium , Matériaux de construction/effets indésirables , Composés du fer II , Portugal , Potassium/analyse , Saisons , Spectrométrie gamma , Thorium/analyse , Uranium/analyse
4.
Radiat Prot Dosimetry ; 160(1-3): 226-30, 2014 Jul.
Article de Anglais | MEDLINE | ID: mdl-24743768

RÉSUMÉ

Recently, the idea of generating radon map of Brazil has emerged. First attempts of coordinating radon surveys--carried out by different groups across the country--and initial discussions on how to proceed on a larger scale were made at the First Brazilian Radon Seminary, Natal, September 2012. Conventionally, it is believed that indoor radon is no major problem in Brazil, because the overall benign climate usually allows high ventilation rates. Nevertheless, scattered measurements have shown that moderately high indoor radon concentrations (up to a few hundred Bq m⁻³) do occur regionally. Brazilian geology is very diverse and there are regions where an elevated geogenic radon potential exists or is expected to exist. Therefore, a Brazilian Radon Survey is expected to be a challenge, although it appears an important issue, given the rising concern of the public about the quality of its environment.


Sujet(s)
Pollution de l'air intérieur/analyse , Contrôle des radiations , Polluants radioactifs/analyse , Radon/analyse , Brésil , Collecte de données , Environnement , Phénomènes géologiques , Logement , Humains
5.
J Environ Radioact ; 112: 96-107, 2012 Oct.
Article de Anglais | MEDLINE | ID: mdl-22694913

RÉSUMÉ

Naturally occurring uranium geochemical anomalies, representative of the several thousand recognized in the Portuguese section of the Iberian Massif and outcropping in three target areas with a total of a few thousand square metres, were subjected to a detailed study (1:1000 scale) to evaluate the radiological health-risk on the basis of a dose assessment. To reach this goal some radioactive isotopes from the uranium, thorium and potassium radioactive series were measured in 52 samples taken from different environmental compartments: soils, stream sediments, water, foodstuff (vegetables) and air; external radiation was also measured through a square grid of 10×10 m, with a total of 336 measurements. The results show that some radioisotopes have high activities in all the environmental compartments as well as a large variability, namely for those of the uranium decay chain, which is a common situation in the regional geological setting. Isotopic disequilibrium is also common and led to an enrichment of several isotopes in the different pathways, as is the case of (226)Ra; maximum values of 1.76 Bq L(-1) (water), 986 Bq kg(-1) (soils) and 18.9 Bq kg(-1) (in a turnip sample) were measured. On the basis of a realistic scenario combined with the experimental data, the effective dose from exposure to ionizing radiation for two groups of the population (rural and urban) was calculated; the effective dose is variable between 8.0 and 9.5 mSv year(-1), which is 3-4 times higher than the world average. Thus, the radiological health-risk for these populations could be significant and the studied uranium anomalies must be taken into account in the assessment of the geochemical background. The estimated effective dose can also be used as typical of the background of the Beiras uranium metalogenetic province and therefore as a "benchmark" in the remediation of the old uranium mining sites.


Sujet(s)
Rayonnement naturel , Exposition environnementale , Dose de rayonnement , Contrôle des radiations , Radio-isotopes/analyse , Humains , Portugal
6.
Int J Immunogenet ; 38(3): 225-31, 2011 Jun.
Article de Anglais | MEDLINE | ID: mdl-21324097

RÉSUMÉ

FcγRIIA binding to IgG subclasses with different levels of affinity is influenced by the polymorphism in the gene that encodes this receptor. The substitution of arginine (R) for histidine (H) in the 131 position defines three allelic patterns, H/H, R/R, and H/R, resulting in FcγRIIA-H/H131 affinity for IgG2 and higher affinity for IgG3 subclasses. Studies have shown the importance of genetic host factors in leishmaniasis and participation of FcγRs on the macrophage infection by amastigote forms and in the immune response to Leishmania sp. We analysed the influence of allelic diversity patterns of the receptor FcγRIIA on American tegumentary leishmaniasis (ATL). FcγRIIA-H/R131 polymorphism was determined by PCR followed by an allele-specific enzymatic digestion in 88 individuals with ATL and 98 healthy volunteer blood donors (control group). The genotypic and allelic distributions of FcγRIIA-H/R131 were similar among the studied groups as well in mild and severe clinical forms of ATL. Our results suggest no association between this allelic polymorphism and susceptibility or resistance to ATL, neither influencing the development of different clinical forms of this illness.


Sujet(s)
Leishmaniose cutanée/génétique , Polymorphisme génétique , Récepteurs du fragment Fc des IgG/génétique , Adolescent , Adulte , Sujet âgé , Allèles , Études cas-témoins , Enfant , Femelle , Fréquence d'allèle/génétique , Génotype , Humains , Mâle , Adulte d'âge moyen , Jeune adulte
7.
Rev. bras. plantas med ; 13(spe): 564-568, 2011. graf, tab
Article de Portugais | LILACS | ID: lil-618332

RÉSUMÉ

O objetivo do trabalho foi avaliar o efeito dos extratos aquosos de hortelã e melissa na germinação e vigor de sementes de tanchagem. O experimento foi conduzido no Departamento de Fitotecnia da Universidade Federal de Viçosa, no mês de abril de 2011. O delineamento utilizado foi o inteiramente casualizado com cinco tratamentos (testemunha, 25 por cento, 50 por cento, 75 por cento e 100 por cento do extrato aquoso de hortelã e melissa) e quatro repetições. Os extratos foram preparados utilizando a parte aérea das plantas, na proporção de 100g de planta para 1 L de água destilada. Foram utilizadas 50 sementes de tanchagem em cada caixa gerbox, previamente umedecido com os extratos aquosos (correspondentes aos tratamentos), estas foram levadas para germinar em câmara de germinação, em temperatura de 20°C, fotoperíodo de 16 horas luz e 8 horas escuro, por 14 dias. Durante esse tempo foram feitas às contagens diárias das sementes germinadas para calcular o índice de velocidade de germinação e ao final dos 14 dias foi calculada a porcentagem de germinação. Sementes de tanchagem não submetidas aos extratos aquosos de melissa e hortelã apresentaram-se mais vigorosas quando comparado com as concentrações, evidenciando o potencial alelopático de melissa e hortelã sobre a sua qualidade fisiológica.


The aim of this work was to evaluate the effect of aqueous extracts of Melissa officinallis and Mentha x villosa for the germination and vigor of Plantago major seeds. The experiment was conducted at the Plant Science Department, Federal University of Viçosa, in April 2011. The design was a completely randomized design with five treatments (control, 25 percent, 50 percent, 75 percent and 100 percent of the aqueous extract of Mentha x villosa and Melissa Officinallis) and four replications. The extracts were prepared utulizando the shoots of plants at the rate of 100g of plant to 1 L of distilled water. We used 50 Plantago major seeds in each box incubator and these were subsequently placed in a germination chamber. 14 days during the counting of germinated seeds per day to calculate the index of germination speed and the end of 14 days was the germination percentage. Plantago major seeds not subjected to aqueous extracts of lemon balm and mint showed higher values in the variables studied when compared to other concentrations, showing the allelopathic potencial of Melissa officinallis and Mentha x villosa on the development of plantain, determined by germinating.


Sujet(s)
Extraits de plantes/analyse , Mentha/métabolisme , Melissa/métabolisme , Plantago/classification , Graines/croissance et développement , Germination , Allélopathie
8.
J Environ Radioact ; 101(10): 875-82, 2010 Oct.
Article de Anglais | MEDLINE | ID: mdl-20554356

RÉSUMÉ

In order to evaluate the influence of faulting on the variability of geogenic radon at detailed scale (1:2000), data on gamma ray fluxes, U and Th concentrations in rocks, radon in soil-gas and radon in groundwater were collected in three target areas on the Oliveira do Hospital region (Central Portugal). This region stands on the Iberian Uranium Province, and is dominantly composed of Hercynian granites and metasedimentary rocks of pre-Ordovician age, crosscut by faults with dominant strike N35 degrees E, N55 degrees E and N75 degrees E. Radiometric anomalies are frequent, associated with faults of the referred systems and metasedimentary enclaves; the analytical data confirms that these anomalies are produced by local high uranium contents in rocks and fault-filling materials (n=34, range 13-724 ppm), while other radiogenic elements are relatively constant (e.g. Th 4-30 ppm). Radon concentration in soil can be extremely high, up to 12,850 kBq m(-3) (n=215), with a large proportion of results above 100 kBq m(-3). Unsurprisingly, groundwater also shows high radon concentrations, with observed values in the range 150-4850 Bq.L(-1) (n=17). From the results it is concluded that metasedimentary enclaves, as well as faults, can accumulate uranium from circulating fluids, and as a consequence, strongly locally enhance geogenic radon potential. Due to this fact, for the purpose of land use planning in such uranium-enriched regions, very detailed geological mapping is needed to precisely recognize radon high risk areas. A correlation between radon concentration in soil or in groundwater and gamma ray fluxes was established pointing to the possible use of these fluxes as a first step in assessing geogenic radon potential, at least to geological setting similar to the study area.


Sujet(s)
Polluants atmosphériques radioactifs/analyse , Contrôle des radiations/méthodes , Radon/analyse , Polluants radioactifs du sol/analyse , Portugal , Uranium/analyse
9.
J Environ Radioact ; 100(10): 896-904, 2009 Oct.
Article de Anglais | MEDLINE | ID: mdl-19632749

RÉSUMÉ

Indoor radon activities were measured during a period of 6 months, as well as several physical environmental variables (temperature, pressure, humidity and rainfall). The location was a small room at an administrative building of the University of Coimbra, usually undisturbed by human activities and situated over bedrock of low-uranium Triassic red sandstones. A low average activity of radon was observed (36 Bq m(-3)), however showing a very well marked daily periodicity (10+/-5 Bq m(-3)), with maximum values occurring more frequently between 9 and 10 a.m. Daily variations are shown to have no relation with earth tides, and their amplitudes exhibit a significant correlation with outdoor temperature; no dependence on barometric pressure was found. Rainfall disturbs the observed daily radon cycles through a strong reduction of their amplitude, but has no effect on the long-term variability of the gas concentration.


Sujet(s)
Polluants atmosphériques radioactifs/analyse , Pollution de l'air intérieur/analyse , Périodicité , Radon/analyse , Pollution de l'air intérieur/statistiques et données numériques , Géographie , Cinétique , Portugal , Contrôle des radiations , Facteurs temps
11.
Biochem Genet ; 39(9-10): 289-96, 2001 Oct.
Article de Anglais | MEDLINE | ID: mdl-11758725

RÉSUMÉ

The polyacrylamide gel electrophoresis system (PAGE) and inhibition tests for biochemical characterization of alpha- and beta-esterases were used to obtain a functional classification of esterases in plants and to show a differential expression of esterases as markers of pathogenesis in cassava plants (Manihot esculenta Crantz). The characterization of alpha- and beta-esterases from leaves of M. esculenta by the PAGE system was possible using an extraction solution containing two phenol-complexing agents (PVP-40 and sodium metabisulfite), three antioxidant agents (EDTA, beta-mercaptoethanol, and DTT), and one quinone reducer (ascorbic acid). Fourteen esterase isozymes were detected in young unexpanded leaves of M. esculenta cultivars. The inhibition pattern of alpha- and beta-esterases of M. esculenta showed that Est-9 is an arylesterase, and in the unexpanded leaves of the M. esculenta plants infected with Xanthomonas axonopodis pv. manihotis, the Est-7 beta-esterase showed the characteristic staining of an alpha/beta-esterase. This diffrential expression of Est-7 isozyme in young unexpanded leaves of cassava plants can be used as a marker of pathogenesis after infection with X. axonopodis pv. manihotis.


Sujet(s)
Esterases/métabolisme , Manihot/enzymologie , Manihot/microbiologie , Xanthomonas/pathogénicité , Électrophorèse sur gel de polyacrylamide , Esterases/isolement et purification , Isoenzymes/isolement et purification , Isoenzymes/métabolisme , Maladies des plantes/microbiologie , Feuilles de plante/enzymologie
12.
Rev Soc Bras Med Trop ; 33(1): 75-8, 2000.
Article de Portugais | MEDLINE | ID: mdl-10881122

RÉSUMÉ

Cryptococcosis is considered the most frequent fungal systemic opportunist infection in patients with AIDS. C. neoformans var. neoformans infects the patients with AIDS more often than C. neoformans var. gattii which has been rarely isolated from patients with AIDS. Even in endemic regions of C. neoformans var. gattii, the variety of neoformans is still the most common agent diagnosed in cryptococcosis of patients with AIDS. Cerebrospinal fluid (CSF) from fifty patients with neurocryptococcosis associated with AIDS were studied. The fungi were isolated in agar Sabouraud medium, and were identified by microscopic and macroscopic examination by agar Sabouraud, agar niger and Christensen's urea medium. The variety was determined based on a color characteristic reaction on glycine-L-canavanina-bromothymol blue agar. From all of the fifty patients' cerebrospinal fluid (CSF) we were able to recover C. neoformans. The isolates were identified as C. neoformans var. neoformans in 47 patients and as C. neoformans var. gattii. in the 3 remaining patients. These findings suggest that both varieties, gattii and neoformans, are agents of neurocryptococcosis in patients with AIDS.


Sujet(s)
Syndrome d'immunodéficience acquise/microbiologie , Cryptococcus neoformans/isolement et purification , VIH-1 (Virus de l'Immunodéficience Humaine de type 1) , Infections opportunistes liées au SIDA/liquide cérébrospinal , Infections opportunistes liées au SIDA/microbiologie , Syndrome d'immunodéficience acquise/liquide cérébrospinal , Adulte , Liquide cérébrospinal/microbiologie , Femelle , Humains , Mâle , Méningite cryptococcique/liquide cérébrospinal , Méningite cryptococcique/microbiologie , Adulte d'âge moyen
13.
Braz Dent J ; 11(2): 141-6, 2000.
Article de Anglais | MEDLINE | ID: mdl-11210263

RÉSUMÉ

Endodontic retreatment of a maxillary right lateral incisor with two root canals is described. The diagnosis of fusion, gemination or dens invaginatus could not be made, due to conflicting findings, and to previous root canal treatment that erased the original configuration of the pulp chamber.


Sujet(s)
Dens in dente/diagnostic , Cavité pulpaire de la dent/malformations , Dents fusionnées/diagnostic , Incisive/malformations , Adulte , Diagnostic différentiel , Femelle , Études de suivi , Humains , Maxillaire , Reprise du traitement , Produits d'obturation des canaux radiculaires/usage thérapeutique , Liquides d'irrigation endocanalaire/usage thérapeutique , Traitement de canal radiculaire/méthodes
14.
Phys Med Biol ; 44(3): N31-8, 1999 Mar.
Article de Anglais | MEDLINE | ID: mdl-10211813

RÉSUMÉ

The lack of well established dosimetry protocols for HDR sources is a point of great concern regarding the uniformity of procedures within a particular country and worldwide. The main objective of this paper is to report the results from ten institutions of an intercomparison of calibration procedures for 192Ir HDR sources currently in use in Brazil. The treatment irradiator of one institution was calibrated by a reference system and used by all participants with their own measuring electrometers and ionization chambers under the same experimental conditions. Two methods were used: the calibration jig and the well-type ionization chamber. Each participant was allowed to use their own method and formalism. The results of this exercise were very positive since this was the first time in Brazil that a group of users gathered to share their experience and openly discuss the physical concepts behind the calibration procedures. The results were all within +/-3.0%, except one case where -4.6% was observed and later identified as a problem with the Nk value for x-rays. Though the magnitude of the deviations found was generally acceptable considering the diversity of formalisms currently in use, a proposal is now being prepared to be adopted as a national protocol. The identification of the institutions was left out for the sake of confidentiality.


Sujet(s)
Radio-isotopes de l'iridium/analyse , Radiométrie , Curiethérapie , Brésil , Calibrage , Rayons gamma
15.
J Cell Biol ; 136(5): 1081-90, 1997 Mar 10.
Article de Anglais | MEDLINE | ID: mdl-9060472

RÉSUMÉ

The kinesin superfamily is a large group of proteins (kinesin-like proteins [KLPs]) that share sequence similarity with the microtubule (MT) motor kinesin. Several members of this superfamily have been implicated in various stages of mitosis and meiosis. Here we report our studies on KLP67A of Drosophila. DNA sequence analysis of KLP67A predicts an MT motor protein with an amino-terminal motor domain. To prove this directly, KLP67A expressed in Escherichia coli was shown in an in vitro motility assay to move MTs in the plus direction. We also report expression analyses at both the mRNA and protein level, which implicate KLP67A in the localization of mitochondria in undifferentiated cell types. In situ hybridization studies of the KLP67A mRNA during embryogenesis and larval central nervous system development indicate a proliferation-specific expression pattern. Furthermore, when affinity-purified anti-KLP67A antisera are used to stain blastoderm embryos, mitochondria in the region of the spindle asters are labeled. These data suggest that KLP67A is a mitotic motor of Drosophila that may have the unique role of positioning mitochondria near the spindle.


Sujet(s)
Protéines de Drosophila , Drosophila/génétique , Protéines associées aux microtubules/analyse , Microtubules/métabolisme , Mitochondries/composition chimique , Mitose/physiologie , Séquence d'acides aminés , Animaux , Séquence nucléotidique , Cellules CHO , Cricetinae , ADN complémentaire/génétique , Drosophila/embryologie , Escherichia coli/génétique , Régulation de l'expression des gènes au cours du développement , Protéines associées aux microtubules/génétique , Protéines associées aux microtubules/isolement et purification , Données de séquences moléculaires , ARN messager/analyse , Protéines de fusion recombinantes/métabolisme
16.
Mol Biol Cell ; 6(11): 1563-74, 1995 Nov.
Article de Anglais | MEDLINE | ID: mdl-8589456

RÉSUMÉ

The KLP61F gene product is essential for Drosophila development. Mutations in KLP61F display a mitotic arrest phenotype caused by a failure in the proper separation of duplicated centrosomes (Heck et al., 1993). Sequence analysis of KLP61F identified it as a member of the bimC family of kinesin-like microtubule motor proteins. Here we report that KLP61F is distinct from KRP130, a kinesin-like protein recently purified from Drosophila embryos and suggested to be the product of the KLP61F gene (Cole et al., 1994). We also characterized recombinant KLP61F and found that it possesses microtubule-stimulated ATPase and microtubule translocation activities in vitro. In addition, we have used an affinity-purified, KLP61F-specific antiserum to localize native KLP61F and an epitope-tagged KLP61F fusion protein during various stages of mitosis in Drosophila syncytial blastoderm embryos. From early prophase through anaphase, KLP61F is coincident with the distribution of tubulin. Together these results confirm the existence of multiple bimC-like kinesins in Drosophila and suggest that KLP61F function is intrinsic to the mitotic spindle.


Sujet(s)
Protéines de Drosophila , Drosophila/physiologie , Protéines associées aux microtubules/physiologie , Appareil du fuseau/physiologie , Adenosine triphosphatases/analyse , Adenosine triphosphatases/biosynthèse , Adenosine triphosphatases/métabolisme , Animaux , Technique de Western , Clonage moléculaire , Drosophila/embryologie , Drosophila/génétique , Embryon non mammalien/physiologie , Épitopes , Technique d'immunofluorescence indirecte , Expression des gènes , Gènes d'insecte , Protéines associées aux microtubules/analyse , Protéines associées aux microtubules/biosynthèse , Microtubules/ultrastructure , Mutagenèse , Protéines de fusion recombinantes/analyse , Protéines de fusion recombinantes/biosynthèse , Protéines de fusion recombinantes/métabolisme , Sites étiquetés par des séquences , Appareil du fuseau/ultrastructure
17.
Genetics ; 139(2): 757-66, 1995 Feb.
Article de Anglais | MEDLINE | ID: mdl-7713430

RÉSUMÉ

We developed a screening approach that utilizes an inverse polymerase chain reaction (PCR) to detect P element insertions in or near previously cloned genes in Drosophila melanogaster. We used this approach in a large scale genetic screen in which P elements were mobilized from sites on the X chromosome to new autosomal locations. Mutagenized flies were combined in pools, and our screening approach was used to generate probes corresponding to the sequences flanking each site of insertion. These probes then were used for hybridization to cloned genomic intervals, allowing individuals carrying insertions in them to be detected. We used the same approach to perform repeated rounds of sib-selection to generate stable insertion lines. We screened 16,100 insert bearing individuals and recovered 11 insertions in five intervals containing genes encoding members of the kinesin superfamily in Drosophila melanogaster. In addition, we recovered an insertion in the region including the Larval Serum Protein-2 gene. Examination by Southern hybridization confirms that the lines we recovered represent genuine insertions in the corresponding genomic intervals. Our data indicates that this approach will be very efficient both for P element mutagenesis of new genomic regions and for detection and recovery of "local" P element transposition events. In addition, our data constitutes a survey of preferred P element insertion sites in the Drosophila genome and suggests that insertion sites that are mutable at a rate of approximately 10(-4) are distributed every 40-50 kb.


Sujet(s)
Éléments transposables d'ADN , ADN/analyse , Protéines de Drosophila , Drosophila melanogaster/génétique , Dépistage génétique/méthodes , Réaction de polymérisation en chaîne/méthodes , Animaux , Séquence nucléotidique , Clonage moléculaire , Croisements génétiques , Femelle , Hormones des insectes/génétique , Kinésine/génétique , Mâle , Protéines associées aux microtubules/génétique , Données de séquences moléculaires , Mutagenèse , Chromosome X
18.
Rev Port Cardiol ; 10(11): 845-8, 1991 Nov.
Article de Portugais | MEDLINE | ID: mdl-1786169

RÉSUMÉ

A case of Transesophageal Echocardiography (T.E.E.) Assessment of "Rheumatic Mitral Stenosis" is presented. T.E.E. has been recently referred as having superior resolution than transthoracic Echocardiography on the detection of thrombi. In the presented case a thrombi was detected in the left atrial appendage. This fact has allowed a better planning of surgery.


Sujet(s)
Échocardiographie/méthodes , Cardiopathies/imagerie diagnostique , Thrombose/imagerie diagnostique , Sténose tricuspidienne/imagerie diagnostique , Oesophage , Femelle , Atrium du coeur/imagerie diagnostique , Humains , Adulte d'âge moyen
19.
Rev Port Cardiol ; 9(9): 683-6, 1990 Sep.
Article de Portugais | MEDLINE | ID: mdl-2257155

RÉSUMÉ

OBJECTIVE: to assess the experience of both departments in the surgical therapy of infective endocarditis--indications and results. DESIGN: retrospective analysis on clinical data, surgery and follow up. SETTING: patients (pts) studied in the Cardiology Department and Cardiothoracic Surgery Department of the Santa Marta Hospital in Lisbon. PATIENTS AND INTERVENTIONS: sequential sample of 28 patients (11 females, 17 males, mean age 39 years) submitted to surgery between 1978 and 1987 for infective endocarditis. MEASUREMENTS AND RESULTS: the indications for surgery were: heart failure (15 pts), "resistant" infection (8 pts), emboli (4 pts) and "large" vegetations shown by echocardiography (2 pts). Surgical mortality -27.5%. Four patients developed periprosthetic leaks. There was an improvement in functional class of the survivals. CONCLUSION: the indications for surgery were heart failure, "resistant" infection, emboli and "large" vegetations. There was a high surgical mortality, namely in the patients with resistant infection, severe heart failure and periprosthetic leaks. In the follow up there was a net improvement of functional class. The morbidity is due to the periprosthetic leaks, which induced most of the reoperations.


Sujet(s)
Candidose/chirurgie , Endocardite bactérienne/chirurgie , Endocardite/chirurgie , Adolescent , Adulte , Candidose/mortalité , Endocardite/microbiologie , Endocardite/mortalité , Endocardite bactérienne/mortalité , Femelle , Études de suivi , Humains , Mâle , Adulte d'âge moyen , Études rétrospectives
20.
Rev Port Cardiol ; 9(3): 221-5, 1990 Mar.
Article de Portugais | MEDLINE | ID: mdl-2390283

RÉSUMÉ

We report the case of a 23 year old patient in whom heart disease was detected in childhood. He began to have suddenly fever and symptoms of right side heart failure. There were signs of aortic regurgitation, a systodiastolic murmur in the left parasternal region and a diastolic murmur in the left 4th intercostal space. The bidimensional and Doppler Echocardiogram showed a saccular dilatation in the right ventricular outflow tract. He was submitted to catheterisation which confirmed aortic regurgitation and detected ventricular septal defect and pulmonary hypertension. During surgery, a subaortic ventricular septal defect was seen as well as a dilatation of the right coronary aortic cusp which prolapsed through the defect to the right ventricular outflow tract. Vegetations were seen in the pulmonary valve. The aortic valve and a pulmonary cusp were excised and a Björk Shiley aortic prosthetic valve was inserted. The septal defect was closed. The patient is still alive, symptomless, with 40 months of follow up. We discuss some problems related to this case, particularly the surgical indication and the rarity of the morphology discovered.


Sujet(s)
Insuffisance aortique/complications , Endocardite bactérienne/complications , Communications interventriculaires/complications , Valve du tronc pulmonaire , Adulte , Humains , Mâle
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