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1.
Lupus ; 29(2): 182-190, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31948350

RESUMO

We have explored the relationship between possible hemostatic changes and clinical manifestation of the systemic lupus erythematosus (SLE) as a function of greater or lesser disease activity according to Systemic Lupus Erythematosus Disease Activity Index-2000 (SLEDAI-2K) criteria. Endothelial injury and hypercoagulability were investigated in patients with SLE by measuring thrombomodulin (TM), D-dimer (DDi) and thrombin generation (TG) potential. A total of 90 participants were distributed into three groups: 1) women with SLE presenting with low disease activity (laSLE) (SLEDAI-2K ≤ 4), 2) women with SLE presenting with moderate to high disease activity (mhaSLE) (SLEDAI-2K > 4), and 3) a control group comprising healthy women. Levels of TM and DDi were higher both in the laSLE and mhaSLE groups compared to controls and in mhaSLE compared to the laSLE group. With respect to TG assay, lagtime and endogen thrombin potential, low concentrations of tissue factor provided the best results for discrimination among groups. Analysis of these data allow us to conclude that TM, DDi and TG are potentially useful markers for discriminating patients with very active from those with lower active disease. Higher SLE activity may cause endothelial injury, resulting in higher TG and consequently a hypercoagulability state underlying the picture of thrombosis common in this inflammatory disease.


Assuntos
Endotélio Vascular/patologia , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/patologia , Trombofilia/patologia , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Estudos Transversais , Endotélio Vascular/fisiopatologia , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Humanos , Lúpus Eritematoso Sistêmico/fisiopatologia , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Trombomodulina/sangue , Trombofilia/fisiopatologia , Tromboplastina/análise , Adulto Jovem
2.
J Helminthol ; 92(3): 353-368, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28502254

RESUMO

Five species of Urocleidoides (one new) and two new species of Constrictoanchoratus n. gen. are described in this study. All were collected from the gills of Hoplias malabaricus (Characiformes: Erythrinidae) captured in six localities of coastal rivers of the north-eastern sector the State of Pará (Oriental Amazon): Urocleidoides brasiliensis Rosim, Mendoza-Franco & Luque, 2011; Urocleidoides bulbophallus n. sp.; Urocleidoides cuiabai Rosim, Mendoza-Franco & Luque, 2011; Urocleidoides eremitus Kritsky, Thatcher & Boeger, 1986; Urocleidoides malabaricusi Rosim, Mendoza-Franco & Luque, 2011; Constrictoanchoratus lemmyi n. gen. n. sp.; and Constrictoanchoratus ptilonophallus n. gen. n. sp. This is the first reported occurrence of the four previously described species of Urocleidoides parasitizing H. malabaricus from streams in the Oriental Amazon Basin. The analysis of voucher specimens of U. eremitus parasitizing the gills of H. malabaricus from the Upper Paraná River floodplain in the limits of States of Paraná and Mato Grosso do Sul, Brazil, indicates that these specimens are members of a new species of Urocleidoides, described here as Urocleidoides paranae n. sp. Constrictoanchoratus n. gen. is proposed for the species with a male copulatory organ sclerotized, coiled, clockwise; ventral anchor with elongate superficial root, inconspicuous deep root; dorsal anchor with inconspicuous roots, and a constriction at the intersection between the shaft and the point. The host-parasite diversity scenario and host specificity of the species of Constrictoanchoratus n. gen. and Urocleidoides from the gills of H. malabaricus are also discussed in this study.


Assuntos
Caraciformes/parasitologia , Doenças dos Peixes/parasitologia , Brânquias/parasitologia , Platelmintos/classificação , Platelmintos/isolamento & purificação , Rios/parasitologia , Animais , Brasil/epidemiologia , Doenças dos Peixes/epidemiologia , Especificidade de Hospedeiro , Interações Hospedeiro-Parasita , Platelmintos/anatomia & histologia , Platelmintos/genética
3.
Stud Mycol ; 86: 1-28, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28348446

RESUMO

The order Chaetothyriales (Pezizomycotina, Ascomycetes) harbours obligatorily melanised fungi and includes numerous etiologic agents of chromoblastomycosis, phaeohyphomycosis and other diseases of vertebrate hosts. Diseases range from mild cutaneous to fatal cerebral or disseminated infections and affect humans and cold-blooded animals globally. In addition, Chaetothyriales comprise species with aquatic, rock-inhabiting, ant-associated, and mycoparasitic life-styles, as well as species that tolerate toxic compounds, suggesting a high degree of versatile extremotolerance. To understand their biology and divergent niche occupation, we sequenced and annotated a set of 23 genomes of main the human opportunists within the Chaetothyriales as well as related environmental species. Our analyses included fungi with diverse life-styles, namely opportunistic pathogens and closely related saprobes, to identify genomic adaptations related to pathogenesis. Furthermore, ecological preferences of Chaetothyriales were analysed, in conjuncture with the order-level phylogeny based on conserved ribosomal genes. General characteristics, phylogenomic relationships, transposable elements, sex-related genes, protein family evolution, genes related to protein degradation (MEROPS), carbohydrate-active enzymes (CAZymes), melanin synthesis and secondary metabolism were investigated and compared between species. Genome assemblies varied from 25.81 Mb (Capronia coronata) to 43.03 Mb (Cladophialophora immunda). The bantiana-clade contained the highest number of predicted genes (12 817 on average) as well as larger genomes. We found a low content of mobile elements, with DNA transposons from Tc1/Mariner superfamily being the most abundant across analysed species. Additionally, we identified a reduction of carbohydrate degrading enzymes, specifically many of the Glycosyl Hydrolase (GH) class, while most of the Pectin Lyase (PL) genes were lost in etiological agents of chromoblastomycosis and phaeohyphomycosis. An expansion was found in protein degrading peptidase enzyme families S12 (serine-type D-Ala-D-Ala carboxypeptidases) and M38 (isoaspartyl dipeptidases). Based on genomic information, a wide range of abilities of melanin biosynthesis was revealed; genes related to metabolically distinct DHN, DOPA and pyomelanin pathways were identified. The MAT (MAting Type) locus and other sex-related genes were recognized in all 23 black fungi. Members of the asexual genera Fonsecaea and Cladophialophora appear to be heterothallic with a single copy of either MAT-1-1 or MAT-1-2 in each individual. All Capronia species are homothallic as both MAT1-1 and MAT1-2 genes were found in each single genome. The genomic synteny of the MAT-locus flanking genes (SLA2-APN2-COX13) is not conserved in black fungi as is commonly observed in Eurotiomycetes, indicating a unique genomic context for MAT in those species. The heterokaryon (het) genes expansion associated with the low selective pressure at the MAT-locus suggests that a parasexual cycle may play an important role in generating diversity among those fungi.

4.
Genet Mol Res ; 16(3)2017 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-28973715

RESUMO

The objective of this study was to estimate the genetic effects on in vitro germination and development of chili peppers. For this, four genotypes (UFPB-132, -134, -137, and -390) were used as parents. They were crossed in a complete diallel scheme. The parents (4) and hybrid (12) seeds were germinated in glass bottles containing MS media. The following variables were evaluated: seed germination percentage, deformed seedlings percentage, radicle emission percentage, root length, root number, hypocotyl length, hypocotyl width, definitive leaf number, leaf length, and leaf width. The data were submitted to analysis of variance and the means were grouped by the Scott-Knott criteria (P ≤ 0.05). The diallel analysis was performed according to the Griffing method, method I, fixed model. Significant differences for all analysed variables were observed. Additive and non-additive effects were observed influencing the performance of the genotypes in relation to the evaluated variables. The genitor 132 showed the highest general combining ability for almost all evaluated characteristics, except seed germination percentage and deformed seedlings percentage. This study revealed dominance effects are responsible for genotypic variation for almost all evaluated traits. In addition, we found significant reciprocal effects for all studied characters. For the traits to which non-additive variances were important (germination percentage, deformed seedlings percentage, root number, hypocotyl length, hypocotyl width, and definitive leaf number, leaf length, and leaf width), there was an additional opportunity for developing F1 hybrid.


Assuntos
Capsicum/genética , Genótipo , Germinação , Capsicum/crescimento & desenvolvimento , Variação Genética , Hipocótilo/crescimento & desenvolvimento , Característica Quantitativa Herdável
5.
Metrologia ; 54(1A)2017.
Artigo em Inglês | MEDLINE | ID: mdl-33100400

RESUMO

In 2016, comparisons of activity measurements of 18F and 64Cu using the Transfer Instrument of the International Reference System (SIRTI) took place at the National Institute of Standards and Technology (NIST, USA). This is the first SIRTI comparison for 64Cu. Ampoules containing about 27 kBq of 18F and 100 kBq of 64Cu solutions were measured in the SIRTI for about 5 and 1.5 half-lives, respectively. The NIST standardized the activity in the ampoules by ionization chamber measurements traceable to 4π(LS)ß-γ anticoincidence measurements. The comparisons, identifiers BIPM.RI(II)-K4.F-18 and BIPM.RI(II)-K4.Cu-64, are linked to the corresponding BIPM.RI(II)-K1.F-18 and BIPM.RI(II)-K1.Cu-64 comparisons and degrees of equivalence with the respective key comparison reference values have been evaluated. The NIST replaces its earlier degree of equivalence for 18F obtained in the frame of the CCRI(II)-K3.F-18 comparison in 2001.

6.
Phys Lett B ; 761: 281-286, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-28057978

RESUMO

The hypothesis that proximity to the Sun causes variation of decay constants at permille level has been tested and disproved. Repeated activity measurements of mono-radionuclide sources were performed over periods from 200 days up to four decades at 14 laboratories across the globe. Residuals from the exponential nuclear decay curves were inspected for annual oscillations. Systematic deviations from a purely exponential decay curve differ from one data set to another and are attributable to instabilities in the instrumentation and measurement conditions. The most stable activity measurements of alpha, beta-minus, electron capture, and beta-plus decaying sources set an upper limit of 0.0006% to 0.008% to the amplitude of annual oscillations in the decay rate. Oscillations in phase with Earth's orbital distance to the Sun could not be observed within a 10-6 to 10-5 range of precision. There are also no apparent modulations over periods of weeks or months. Consequently, there is no indication of a natural impediment against sub-permille accuracy in half-life determinations, renormalisation of activity to a distant reference date, application of nuclear dating for archaeology, geo- and cosmochronology, nor in establishing the SI unit becquerel and seeking international equivalence of activity standards.

7.
Parasite Immunol ; 35(7-8): 214-23, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23607422

RESUMO

Chagas disease was discovered more than a hundred years ago, but its pathogenesis is still not completely understood. Autoimmunity is one of the mechanisms shown to contribute to its pathogenesis, which may indicate an important participation of B lymphocytes. Patients with Chagas disease have shown increased percentage of B cells producing IL-10. However, there are no reports of the phenotypic markers of B cells producing IL-10 in patients with Chagas disease. For the first time in the literature, we evaluated the phenotypic profile of distinct markers of B cells from peripheral blood of noninfected individuals and patients with Chagas disease. Our results showed that patients with Chagas disease had a higher expression of CD21 and CD24 on the surface of CD19+ B cells, while CD43 and CD23 were expressed equally in all groups. Moreover, the expression of MHC-II (HLA-DR), CD80, CD86, caspase-3, granzyme B and intracellular IL-10 and TGF-ß by CD19+ B cells was higher in patients with Chagas disease. The results of IL-10 production within CD19+ CD5+ CD1d+ B cells showed a higher percentage of this cytokine in patients with Chagas disease. Thus, our data bring a new knowledge about distinct markers of B cells in immune responses of Chagas disease.


Assuntos
Linfócitos B/imunologia , Doença de Chagas/imunologia , Adulto , Antígenos CD/análise , Linfócitos B/metabolismo , Biomarcadores/análise , Caspase 3/metabolismo , Doença de Chagas/metabolismo , Feminino , Antígenos HLA-DR/imunologia , Antígenos HLA-DR/metabolismo , Humanos , Imunofenotipagem , Interleucina-10/biossíntese , Interleucina-10/imunologia , Masculino , Pessoa de Meia-Idade , Fator de Crescimento Transformador beta/metabolismo , Trypanosoma cruzi/imunologia
8.
Scand J Immunol ; 75(2): 142-6, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21923739

RESUMO

Sporotrichosis is a chronic granulomatous mycosis caused by the dimorphic fungus Sporothrix schenckii. The immunological mechanisms involved in the prevention and control of sporotrichosis suggest that cell-mediated immunity plays an important role in protecting the host against S. schenckii. Nonetheless, recent data strongly support the existence of protective Abs against this pathogenic fungus. In a previous study, we showed that passive Ab therapy led to a significant reduction in the number of colony forming unit in the organs of mice when the MAb was injected before and during S. schenckii infection. The ability of opsonization to enhance macrophage damage to S. schenckii and subsequent cytokine production was investigated in this work. Here we show that the fungicidal characteristics of macrophages are increased when the fungus is phagocytosed in the presence of inactivated serum from mice infected with S. schenckii or mAb anti-gp70. Additionally, we show an increase in the levels of pro-inflammatory cytokines such as TNF-α and IL-1ß. This study provides additional support for the importance of antibodies in protecting against S. schenckii and concludes that opsonization is an important process to increase TNF-α production and fungus killing by macrophages in experimental sporotrichosis.


Assuntos
Anticorpos Antifúngicos/farmacologia , Macrófagos/efeitos dos fármacos , Proteínas Opsonizantes/farmacologia , Fagocitose/efeitos dos fármacos , Sporothrix/imunologia , Esporotricose/imunologia , Fator de Necrose Tumoral alfa/biossíntese , Animais , Anticorpos Antifúngicos/isolamento & purificação , Linhagem Celular , Feminino , Soros Imunes/química , Imunidade Celular/efeitos dos fármacos , Interleucina-1beta/biossíntese , Macrófagos/imunologia , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Viabilidade Microbiana , Proteínas Opsonizantes/isolamento & purificação , Esporotricose/microbiologia , Esporotricose/patologia
9.
Scand J Immunol ; 76(3): 311-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22670682

RESUMO

Although the pathophysiology of Chagas disease is not completely understood, it is widely accepted that involvement of the immune response is critical in determining the outcome of the disease. In this context, CD4⁺ T cells may play an important role in generating different mechanisms of protection. In addition to effector and regulatory functions, CD4⁺ T cells may be also involved with lytic activities against the parasite and may have a relevant role on control of the infection. In this study, we have evaluated CD4⁺ T cells expressing cytotoxic and apoptosis markers in response to Trypanossoma cruzi infection in indeterminate (IND) and cardiac (CARD) patients with Chagas disease and non-infected individuals (NI). Our data demonstrated that: (1) CD4⁺ T cells presented higher ex vivo granzyme B expression in patients with Chagas disease compared with healthy individuals and that antigen induced a greater granzyme B expression in IND patients; (2) CD95L expression in CD4⁺ CD95⁺ T cells from IND patients is higher than in CARD and NI; (3) IND and CARD patients had an increased frequency of caspase-3 after in vitro stimulation and also expressed a high frequency of annexinV⁺ 7ADD⁺ within CD4⁺ T cells; (4) Lastly, a positive correlation was seen between cytotoxic molecules and CD45RO memory marker in CD4⁺ T cells and between caspase-3 and CD95L within CD4⁺ CD95⁺ T cells. These results suggest new insights into the functional competence of CD4⁺ T cells among the different clinical forms of Chagas disease, which will lead to a better understanding of their influence during immune responses against T. cruzi.


Assuntos
Apoptose/imunologia , Linfócitos T CD4-Positivos/imunologia , Doença de Chagas/imunologia , Subpopulações de Linfócitos T/imunologia , Adulto , Idoso , Animais , Biomarcadores/análise , Linfócitos T CD4-Positivos/metabolismo , Doença de Chagas/complicações , Doença de Chagas/metabolismo , Citotoxicidade Imunológica/imunologia , Feminino , Citometria de Fluxo , Granzimas/imunologia , Granzimas/metabolismo , Cardiopatias/etiologia , Cardiopatias/imunologia , Humanos , Proteína 1 de Membrana Associada ao Lisossomo/imunologia , Proteína 1 de Membrana Associada ao Lisossomo/metabolismo , Masculino , Pessoa de Meia-Idade , Subpopulações de Linfócitos T/metabolismo , Trypanosoma cruzi/imunologia
10.
Indian J Lepr ; 84(4): 317-20, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23720896

RESUMO

The association of hemicrania continua and leprosy has been described in 2008. This relation can be causal or casual. Hemicrania continua is a strictly unilateral, moderate to severe, continuous, indomethacin-responsive primary headache with autonomic cranial symptoms and leprosy is an usual cause of peripheral neuropathy. Prevalence has fallen in the past years, but transmission continues and leprosy remains a public health problem. The objective of this study is to report one case of headache fulfilling the IHS criteria for HC, presented during the course of leprosy. A 61 years old woman started hypo and hiperpigmented lesions with impaired sensation to touch on right side of face (malar). She had biopsy in facial lesion and histopathology compatible with a borderline leprosy form. At the same time, she reported new headaches, daily and continuous, without pain-free periods, unilateral (which were located in the same side of the leprosy lesion in face), throbbing and severe (VAS = 8) with ipsilateral conjuntival injection and lacrimation that improved with indomethacin. We hypothesize that the local injury on the face of this patient predisposes a mechanism of central sensitization, resulting in trigeminal autonomic cephalgia. Relation between trigemino-autonomic cephalalgias and leprosy provides insights into craniofacial pain mechanisms.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Dor Facial/complicações , Indometacina/uso terapêutico , Hanseníase Dimorfa/complicações , Transtornos de Enxaqueca/complicações , Biópsia , Brasil , Face/patologia , Dor Facial/tratamento farmacológico , Feminino , Humanos , Hanseníase Dimorfa/tratamento farmacológico , Hanseníase Dimorfa/transmissão , Pessoa de Meia-Idade , Transtornos de Enxaqueca/tratamento farmacológico , Resultado do Tratamento
11.
Reprod Domest Anim ; 46(1): 1-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19645857

RESUMO

The uterus is a well-known target of endocrine, paracrine and autocrine acting molecules among which steroid hormones are of special importance. The objective of our work was to localize oestrogen receptors (ERα and ERß) mRNA and protein in the pig uterus throughout pregnancy (10, 18, 32, 50, 71, 90 days post coitum) using RT-PCR, Western-blot and immunohistochemistry. The present study is the first one to demonstrate the presence of ERs protein in the porcine uterus not only at the beginning but also at mid- and late pregnancy. In the pregnant swine, ERα was immunolocalized in the luminal epithelium (LE) and glandular epithelium (GE) and the myometrium of the uterus with differences in the intensity of staining at different stages of pregnancy studied. The LE and GE of pregnant swine stained for ERß regardless of the day of pregnancy examined, whereas only a few cells within the myometrium showed a weak immunoreactivity. Western blot analysis confirmed the presence of ERα and ERß proteins on all investigated days of gestation. The expression of ERα and ERß mRNA was detected by RT-PCR in all examined samples corresponding to each of the consecutive stages of pregnancy. The obtained results show that ERα is more abundant in comparison to ERß within the porcine pregnant uterus. The presence of ERα and ERß in all compartments of the pig uterus during pregnancy may indicate direct action of oestrogens on proliferation and differentiation of these cells.


Assuntos
Receptor alfa de Estrogênio/análise , Receptor beta de Estrogênio/análise , Suínos/metabolismo , Útero/química , Animais , Western Blotting , Epitélio/química , Receptor alfa de Estrogênio/genética , Receptor beta de Estrogênio/genética , Feminino , Expressão Gênica , Idade Gestacional , Imuno-Histoquímica , Miométrio/química , Gravidez , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
J Fish Biol ; 77(3): 468-78, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20701634

RESUMO

Knodus dorsomaculatus, a new species, is described from Teles Pires River, a tributary of the Tapajós River, Brazil. It can be distinguished from its congeners by the presence of a conspicuous dark blotch on the base of the first five branched dorsal fin rays and the presence of ii,9 dorsal fin rays. Additional comparisons between K. dorsomaculatus and its congeners are presented.


Assuntos
Peixes/classificação , Animais , Brasil , Feminino , Peixes/anatomia & histologia , Masculino , Rios , Especificidade da Espécie
13.
Appl Radiat Isot ; 134: 74-78, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29158037

RESUMO

In External Beam Radiotherapy, National Metrology Institutes (NMIs) play a critical role in the delivery of accurate absorbed doses to patients undergoing treatment. In contrast for nuclear medicine the role of the NMI is less clear and although significant work has been done in order to establish links for activity measurement, the calculation of administered absorbed doses is not traceable in the same manner as EBRT. Over recent decades the use of novel radiolabelled pharmaceuticals has increased dramatically. The limitation of secondary complications due to radiation damage to non-target tissue has historically been achieved by the use of activity escalation studies during clinical trials and this in turn has led to a chronic under dosing of the majority of patients. This paper looks to address the difficulties in combining clinical everyday practice with the grand challenges laid out by national metrology institutes to improve measurement capability in all walks of life. In the life sciences it can often be difficult to find the correct balance between pure research and practical solutions to measurement problems, and this paper is a discussion regarding these difficulties and how some NMIs have chosen to tackle these issues. The necessity of establishing strong links to underlying standards in the field of quantitative nuclear medicine imaging is highlighted. The difficulties and successes of current methods for providing traceability in nuclear medicine are discussed.


Assuntos
Radiometria/métodos , Compostos Radiofarmacêuticos/análise , Dosagem Radioterapêutica , Radioterapia/métodos , Ensaios Clínicos como Assunto , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/radioterapia , Medicina Nuclear , Compostos Radiofarmacêuticos/administração & dosagem
14.
Appl Radiat Isot ; 134: 6-12, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28947247

RESUMO

Some authors have raised doubt about the invariability of decay constants, which would invalidate the exponential-decay law and the foundation on which the common measurement system for radioactivity is based. Claims were made about a new interaction - the fifth force - by which neutrinos could affect decay constants, thus predicting changes in decay rates in correlation with the variations of the solar neutrino flux. Their argument is based on the observation of permille-sized annual modulations in particular decay rate measurements, as well as transient oscillations at frequencies near 11 year-1 and 12.7 year-1 which they speculatively associate with dynamics of the solar interior. In this work, 12 data sets of precise long-term decay rate measurements have been investigated for the presence of systematic modulations at frequencies between 0.08 and 20 year-1. Besides small annual effects, no common oscillations could be observed among α, ß-, ß+ or EC decaying nuclides. The amplitudes of fitted oscillations to residuals from exponential decay do not exceed 3 times their standard uncertainty, which varies from 0.00023 % to 0.023 %. This contradicts the assertion that 'neutrino-induced' beta decay provides information about the deep solar interior.

15.
Appl Radiat Isot ; 109: 151-153, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26640235

RESUMO

A new determination of the (109)Cd half-life was made by a time series of measurements of an aqueous sample using a re-entrant type ionisation chamber. The measurement campaign covered a period of 6 years or approximately 4.7 half-lives of (109)Cd. The resulting value of 462.1 (3) days is in good agreement with the recently published values of 462.29 (30) days and 462.3 (8) days. This new half-life determination will allow evaluators to specify a recommended value of the (109)Cd half-life making it more accurate and precise.

16.
Appl Radiat Isot ; 109: 17-23, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26682894

RESUMO

In 2014, the first three comparisons of activity measurements of (18)F were carried out at the VNIIM, NPL and the ENEA-INMRI using the BIPM's Transfer Instrument of the International Reference System. The transfer instrument and the NMIs primary measurement methods are briefly described. The degrees of equivalence with the key comparison reference value defined in the frame of the corresponding SIR comparison have been evaluated. World-wide consistency of activity measurements of (18)F is demonstrated.


Assuntos
Radioisótopos de Flúor/análise , Radioisótopos de Flúor/normas , Laboratórios/normas , Medicina Nuclear/normas , Radiometria/normas , Internacionalidade , Doses de Radiação , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Biochim Biophys Acta ; 555(1): 13-25, 1979 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-314306

RESUMO

Isolated frog skins (without chorion) were incubated with 42K+ Ringers' solution, bathing the internal surface for 2 h. All the K+ contained in the frog skin was equilibrated in specific activity with external 42K+. The kinetics of the washout of 42K+ from the internal surface of the skin exhibits one fast and one slow exponential component. Amiloride reduces the release of 42K+ corresponding to both components without affecting the K+ content of the skin. Ouabain increases the loss of 42K+ of the slow component by 200%. Since the total K+ in the skin decreases to 25% of its original value both compartments are affected. The results suggest that two distinct functional compartments exist defined by two 42K+ release ratios and that because of the large K+ contents of these compartments both are intracellular. The relation with the transepithelial Na+ transport and the morphological identification of these compartments is discussed.


Assuntos
Potássio/metabolismo , Pele/metabolismo , Animais , Anuros , Transporte Biológico/efeitos dos fármacos , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Cinética , Ouabaína/farmacologia , Rana temporaria , Pele/efeitos dos fármacos
18.
Biochim Biophys Acta ; 510(2): 298-304, 1978 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-307402

RESUMO

1. Cu2+ at a concentration of 10-4 M, when applied to the external side of the frog skin produces an increase in the short-circuit current (Isc). 2. This effect was studied in skins of Rana temporaria adapted to cold,(5 degrees C) and room temperature (20 degrees C), skins of Rana pipiens adapted to cold, and the results compared with those obtained previously with Rana ribibunda. 3. The observed effect is less dependent upon the adaptation to cold than upon the functional state of the skin: skins with low short circuit currents have a bigger response to Cu2+ than skins with high Isc. 4. A species difference cannot be ruled out since skins of Rana ribibunda exhibiting high Isc give good responses to Cu2+. 5. 5,5' -dithiobis (2-nitrobenzoic acid), a sulphydryl-oxidizing reagent, produces an effect similar to that of Cu2+, and dithiothreitol an SH-reducing agent, reverses the effect of this ion. 6. Cu2+ also induces an increase in the unidirectional K+ fluxes and unmasks a net outward potassium flux. 7. The outward K+ flux induced by Cu2+ is sensitive to ouabain. 8. It is concluded that Cu2+ increases the permeability of the external barrier of the frog skin to Na+ and K+, probably by reacting with SH groups.


Assuntos
Cobre/farmacologia , Pele/efeitos dos fármacos , Reagentes de Sulfidrila/farmacologia , Adaptação Fisiológica , Animais , Anuros , Temperatura Baixa , Técnicas In Vitro , Potenciais da Membrana/efeitos dos fármacos , Potássio/metabolismo , Rana pipiens , Rana temporaria , Fenômenos Fisiológicos da Pele , Sódio/metabolismo
19.
Biochim Biophys Acta ; 552(1): 178-82, 1979 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-107970

RESUMO

60Co-EDTA was tested as an extracellular marker in isolated epithelia of frog skin. It was found to be non-toxic for frog skin and 0.1 mM EDTA proved to be enough to saturate any adsorption sites. Comparing with [14C]inulin, 60Co-EDTA marks a slightly greater extracellular space and this volume is constant between 15 min and 2 h. Furthermore it is reproducible and its use simplifies the methodology of the determination of water and electrolyte contents in the cells.


Assuntos
Cobalto/metabolismo , Ácido Edético/metabolismo , Epitélio/metabolismo , Pele/metabolismo , Amilorida/farmacologia , Animais , Anuros , Água Corporal/metabolismo , Radioisótopos de Cobalto , Inulina/metabolismo , Ouabaína , Potássio/metabolismo , Ranidae , Pele/efeitos dos fármacos , Sódio/metabolismo , Vasopressinas/farmacologia
20.
Biochim Biophys Acta ; 646(2): 193-202, 1981 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-7295713

RESUMO

1. Chemical determinations of Cl- in frog skin indicate that the intracellular concentration of this ion is above that corresponding to an equilibrium distribution. 2. Published data on Na+ efflux from the cell compartments into the two external bathing solutions, and on unidirectional fluxes across the whole preparation suggest that there are large unidirectional fluxes across the basolateral membranes. 3. Cl- uptake from the mucosal barrier is very small, and the removal of Cl- from the mucosal bathing solution does not affect the intracellular Cl- concentration. 4. Removal of Cl- from the serosal bathing solution produces a drastic decrease in cell Cl- together with a loss of water. 5. This is accompanied by a less marked effect on Na+ and K+ content of the cells. 6. The removal of Na+ from the serosal bathing solution produces also a decrease in Cl-, Na+ and K+ content of the cells with a marked loss of water. 7. It is suggested that the basolateral membrane of the frog skin is the site of mechanisms able to regulate volume and ion composition of the epithelial cells and that part of these mechanisms consists of a coupling between the movements of Na+ and Cl-.


Assuntos
Cloretos/metabolismo , Potássio/metabolismo , Pele/metabolismo , Sódio/metabolismo , Acetazolamida/farmacologia , Animais , Água Corporal/metabolismo , Matemática , Permeabilidade , Rana ridibunda , Pele/efeitos dos fármacos
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