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In this work, both undoped and Thulium (Tm3+) doped (0.3-10 mol%) magnesium pyrophosphate (Mg2P2O7) powders were synthesized by the solvent evaporation method to study their photo-and thermoluminescent properties. Two crystalline phases were observed in the powders by X-Ray diffraction (XRD), the main phase being Mg2P2O7 and the second one thulium phosphate (TmPO4). The superficial morphology was analyzed by scanning electron microscopy (SEM), which revealed that the powders are agglomerates with an undefined form and grains with non-uniform size distribution. The photoluminescence (PL) emission spectra of Tm3+ doped powders show the 1D2 â 3F4 transition, associated with Tm3+ ions, at 452 and 458 nm. The thermoluminescence (TL) properties were analyzed in the undoped and Tm3+ doped powders exposed to 90Sr beta source. The TL glow curve of Tm3+ doped powders exhibits three maxima at about â64-66 °C, â198-202 °C, and â301 °C. The TL dose-response is sub-linear from 0.11 to 0.54 Gy, linear between 0.79 and 24.95 Gy, and supra-linear from 34.99 to 599.95 Gy. Acceptable repeatability with a coefficient of variation of â¼1% was obtained after ten cycles of irradiation and readout. At 63 d of storage, the powders show fading of 30%, and at 1.6 years (585 d), the integrated TL intensity decays by 47%. The kinetic parameters of activation energy and frequency factor were evaluated using the Initial Rise, Booth, Bohun, and Porfianovitch (BBP) and Hoogenstraaten methods and Glow Curve Deconvolution with a general order kinetic model.
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This work reports on the thermoluminescence (TL) properties and detection of contaminating minerals isolated from Mexican cocoa beans irradiated with gamma radiation and stored for 4 years. Contaminating minerals isolated from cocoa beans consisting of quartz, diopside, plagioclase, albite, and iron oxide with irregular and rectangular grains and average length of 135 µm. Cocoa beans are detected as irradiated even after 4 years of storage using the shape and maximum temperature of the TL glow curve of contaminating minerals. The TL properties of dose-response, and fading of minerals were also analysed. The TL dose-response is linear from 5 to 100 Gy, supra-linear between 250 and 1000 Gy, and sub-linear above 1500 Gy. Based on the TL1/TL2 ratio the minerals are identified as irradiated from 250 Gy to 4500 Gy in the dose-response test and after different storage times in the darkness at room temperature. A continuum trap distribution can be associated with the TL glow curve of minerals using the Tm-Tstop method. First order kinetic peaks were used in the Glow Curve Deconvolution of natural and irradiated (1 and 10 kGy) TL curves.
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Quartzo , Raios gama , TemperaturaRESUMO
Resumen La presencia de alteraciones de señal en resonancia magnética (RM) cerebral durante o posterior a un evento epiléptico es cada vez más reconocida en la literatura. Los cambios de señal peri-ictales se considera que sería el resultado de edema cerebral localizado, defecto de la autorregulación cerebral y disrupción de la barrera hemato-encefálica que ocurre durante una crisis epiléptica sostenida. Reportamos el caso de un hombre de 62 años diagnosticado de un síndrome parietal de instalación subaguda cuyo estudio con RM de cerebro mostró una lesión tumefacta con edema cortico-subcortical de ubicación temporo-occipital derecha. El estudio con electroencefalograma mostró actividad ictal en la misma localización. Se inició terapia con fármacos anticonvulsivantes mostrando franca mejoría clínica y electrofisiológica. El control con RM diferido mostró resolución completa de las alteraciones descritas.
The presence seizure-induced signal changes on brain magnetic resonance imaging (MRI) have been increasingly recognized in the literature. The reversible MRI changes in epileptic patients may be the result of a local brain swelling, a defect of cerebral autoregulation and a blood-brain barrier disruption during sustained epileptogenic activity. We report a 62 years old man diagnosed with a subacute right parietal syndrome. MRI shows a tumefactive lesion in right temporo-occipital lobes mimicking a structural lesion. Electroencephalogram (EEG) exhibits continuous ictal activity in the same region. Antiepileptic drugs were started achieving progressive electro-clinical improvement. Subsequent MRI showed remission of signal changes.
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Humanos , Masculino , Pessoa de Meia-Idade , Convulsões/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Convulsões/fisiopatologia , Diagnóstico Diferencial , Eletroencefalografia , EpilepsiaRESUMO
In the spermatozoa of some species, the ubiquitin-proteasome system detects altered proteins and tags them for elimination by the proteasome. In some species' ejaculates, a high proportion of ubiquitinated spermatozoa (i.e. those having ubiquitin bound to the altered or damaged membrane proteins) has been related to infertility. The aim of this study was to assess whether the percentage of ubiquitinated spermatozoa relates to fertility of dairy bulls and whether ubiquitination increases during protein remodelling that occurs during in vitro spermatic capacitation. Thirty-two frozen semen straws from four high-fertility (ReproMax(®) ) and four normal-fertility (Normal) Holstein-Friesian sires were evaluated. Ubiquitinated and capacitated spermatozoa were quantified by sperm ubiquitin tag immunoassay and chlortetracycline stain, respectively. Fertilizing capacity of sires was assessed by in vitro fertilization. No differences were found between Normal and ReproMax(®) sires with regard to the observed percentage of ubiquitinated spermatozoa (42.97 ± 3.69% and 49.68 ± 9.27%, respectively; p > 0.05). Additionally, no differences were found in the percentage of ubiquitinated spermatozoa as a consequence of spermatic capacitation in either Normal (42.97 ± 3.69% before capacitation vs 44.67 ± 7.5% after; p > 0.05) or ReproMax(®) sires (49.68 ± 9.27% before vs 45.05 ± 7.51% after; p > 0.05). The percentage of ubiquitinated spermatozoa in a thawed sperm samples did not correlate with its in vitro fertilizing capacity; thus, this assay does not prove useful to detect in vivo fertility differences between sires. Additionally, protein degradation occurring during remodelling of the spermatozoon plasma membrane during the capacitation process does not seem to involve the ubiquitin-proteasome system.
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Bovinos , Fertilização/fisiologia , Preservação do Sêmen/veterinária , Espermatozoides/química , Espermatozoides/fisiologia , Animais , Criopreservação/veterinária , Fertilização in vitro/veterinária , Temperatura Alta , Masculino , Preservação do Sêmen/métodos , Capacitação Espermática , Contagem de Espermatozoides/veterinária , UbiquitinaçãoRESUMO
The present paper reports the experimental results of dysprosium doped calcium sulphate (CaSO4:Dy) films deposited by spray pyrolysis method. CaSO4:Dy films were deposited on three different surfaces: glass, aluminum and quartz substrates at temperatures in the range from 450 to 600 °C. Structural and morphological characteristics of CaSO4:Dy films were observed. Thermoluminescent characteristics of films were determined by irradiating ultraviolet energy region. Thermoluminescent glow curve of CaSO4:Dy films with glass and aluminum substrates showed a peak under environmental irradiation. Both TL response glow shape and intensity of CaSO4:Dy films UV irradiated as a function of substrates were studied.
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OBJECTIVE: Rheumatoid arthritis (RA) is an autoimmune disease of unknown etiology in which inflammatory pathology involves T cell activation and the CD28 costimulatory molecule involved in T cell presentation. The gene includes the CD28 IVS3 +17T/C polymorphism that could be associated with susceptibility to RA whereas the soluble concentrations of CD28 (sCD28) could be related to clinical activity. METHODS: We investigated the CD28 IVS3 +17T/C polymorphism in 200 RA patients and 200 healthy subjects (HS). Furthermore, we quantified the sCD28 concentrations in 77 samples of each group. We applied indexes focused to determine the activity and disability (DAS28 and Spanish HAQ-DI, respectively) in RA patients. RESULTS: RA patients had significantly higher frequencies of the CD28 T allele compared to HS (p = 0.032 OR = 1.59, C.I. 1.02-2.49). In addition, the IVS3 +17 T/T genotype frequency was also increased in RA vs. HS (p = 0.026). The RA patients showed higher sCD28 serum levels than HS (p = 0.001). Carriers of the T/T genotype in RA patients showed higher sCD28 levels than C/C carriers (p =0.047). In addition, a correlation between sCD28 and Spanish HAQ-DI (correlation, 0.272; p =0.016), was found. CONCLUSION: The T allele in CD28 IVS3 +17T/C polymorphism is associated with a susceptibility to RA in Western Mexico. In addition, increased sCD28 levels are related to T/T genotype in RA patients.
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Artrite Reumatoide/genética , Antígenos CD28/genética , Polimorfismo de Nucleotídeo Único , Adulto , Antígenos CD28/sangue , Estudos de Casos e Controles , Feminino , Frequência do Gene , Estudos de Associação Genética , Genótipo , Humanos , Íntrons , Masculino , México , Pessoa de Meia-Idade , Adulto JovemRESUMO
Tumor necrosis factor-alpha (TNF-alpha) plays a central role in inflammation, and it has been directly implicated in the pathogenesis of rheumatoid arthritis (RA). TNF-alpha activity is mediated through TNFRI and TNFRII cell surface receptors, which act as physiological attenuators of TNF-alpha activity. We recruited 190 RA patients and 190 healthy subjects (HS) in order to associate the -383A>C TNFRI polymorphism with sTNFRI levels and DAS28 score in RA. In results, sTNFRI levels were higher in RA patients than HS (P = 0.04). The -383A>C TNFRI polymorphism did not show significant differences in both studied groups. However, in the RA group the sTNFRI levels were significantly elevated (P = 0.004) in A/A genotype carriers. In addition, the A/A genotype carriers had the higher DAS28 score than A/C genotype (P = 0.02). These data suggest that -383A>C TNFRI polymorphism is not a susceptibility marker in RA, whereas the increased levels of sTNFRI could reflect the clinical activity in RA patients.
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Artrite Reumatoide/genética , Polimorfismo Genético , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/etnologia , Artrite Reumatoide/imunologia , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Fenótipo , Receptores Tipo I de Fatores de Necrose Tumoral/sangue , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Adulto JovemRESUMO
OBJECTIVE: To measure levels of soluble tumour necrosis factor alpha (TNFalpha) receptor type I (sTNFRI) and type II (sTNFRII) in order to correlate them with C-reactive protein (CRP), rheumatoid factor (RF), erythrocyte sedimentation rate (ESR), and disease activity score (DAS28) in RA patients. METHODS: We recruited 41 RA patients classified according to American College of Rheumatology (ACR) criteria and 38 healthy subjects (HS). sTNFRI and sTNFRII were measured using an enzyme-linked immunosorbent assay (ELISA) kit. Clinical activity in RA patients was evaluated using the Disease Activity Score using 28 joint counts (DAS28). The statistical analysis was realized using SPSS version 10.0. RESULTS: Soluble TNFRI and TNFRII levels were higher in RA patients (p = 0.04 and 0.001, respectively) than HS. Serum levels of sTNFRI correlated with sTNFRII (r = 0.699, p < 0.0001). sTNFRII correlated with DAS28 (r = 0.375, p = 0.017), RF (r = 0.505, p = 0.004), and ESR (r = 0.323, p = 0.042). CONCLUSION: The increased levels of both sTNFRI and sTNFRII suggest a secondary event related to the inflammatory state observed in RA, whereas the correlation of sTNFRII with RF, ESR, and DAS28 reflects the preferential TNFRII shedding induced by TNFalpha. sTNFRII may be useful as an additional inflammatory marker in RA.
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Artrite Reumatoide/sangue , Receptores Tipo II do Fator de Necrose Tumoral/sangue , Receptores Tipo I de Fatores de Necrose Tumoral/sangue , Índice de Gravidade de Doença , Adulto , Biomarcadores/sangue , Sedimentação Sanguínea , Proteína C-Reativa/metabolismo , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fator Reumatoide/sangueRESUMO
Rice hoja blanca virus (RHBV) is a major virus disease of economic importance affecting rice in northern South America, Central America and the Caribbean. This is the first report of transgenic resistance to RHBV and the transformation of an indica rice variety from Latin America. Rice transformed with the RHBV nucleocapsid protein ( N) gene had a significant reduction in disease development. Several reactions were observed that ranged from susceptible to completely resistant plants (immunity). The resistant reactions were characterized by the production of local lesions like a hypersensitive reaction or a recovery phenotype with the emergence of symptom-less new leaves. These transgenic RHBV-resistant rice lines expressed the N gene RNA at low levels that were below the detection limit by Northern blots and only resolved by RT-PCR. The nucleocapsid protein could not be detected in any of the transgenic plants either by Western or ELISA tests. These results suggest that the resistance encoded by the N gene in these plants appears to be mediated by RNA. When challenged with RHBV, the resistant transgenic lines showed a significant increased performance for important agronomic traits including the number of tillers, the number of grains per plant and the yield as compared to the susceptible control. Furthermore, upon inoculation some of the most-resistant transgenic lines showed agronomic traits similar to the uninoculated non-transgenic Cica 8 control. Using both agronomic traits and disease severity as criteria, several of the most-resistant lines were followed through the R(4) generation and demonstrated that the N gene and RHBV resistance was inherited in a stable manner. These transgenic rice lines could become a new genetic resource in developing RHBV-resistant cultivars.
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Proteínas do Capsídeo/genética , Oryza/genética , Oryza/virologia , Vírus de Plantas/genética , Proteínas do Capsídeo/metabolismo , Oryza/metabolismo , Vírus de Plantas/metabolismoRESUMO
UNLABELLED: The objective of this study was to investigate the mid term influence of vessel size in clinical and angiographic outcome, after Wiktor stent implantation in arteries larger and smaller than 3 mm. METHOD: A total of 188 stents were implanted in 167 patients divided in two groups. Group 1: stents implanted in arteries smaller than 3 mm, 40 stents in 38 patients. Group 2: in arteries larger than 3 mm. 148 stents in 129 patients. Clinical follow up and a repeated coronary angiographic study were carried out after six months. RESULTS: Angiographic success was achieved in 97% and 98% cases, with clinical success in 92% and 95% respectively. Acute occlusion occurred in 2 patients of group 1 (5%), and in four patients in group 2 (2.7%); one patient died and four patients suffered a non-fatal myocardial infarction. During clinical follow up, nine patients presented a major complication, two in group 1 and seven in group 2 (5.5% vs. 5.6%). Asymptomatic survival was 86% and 84% respectively. In angiographic follow up we observed a restenosis rate of 41% of the patients in group 1 and 25% of those in group 2. Immediate gain was similar in both groups, but late loss (1.06 +/- 0.85 vs 0.97 +/- 0.86) and loss rate (0.60 vs 0.46) were greater in group 1. CONCLUSION: The frequency of stent thrombosis as well as the incidence of restenosis were higher in arteries smaller than 3 mm. No differences were observed in the incidence of major ischemic events.
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Angioplastia Coronária com Balão , Doença das Coronárias/terapia , Stents , Idoso , Angioplastia Coronária com Balão/instrumentação , Angiografia Coronária , Doença das Coronárias/diagnóstico por imagem , Doença das Coronárias/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
The sequences of RNA-3 and RNA-4 of rice hoja blanca tenuivirus isolates from Colombia and from Costa Rica were determined and analyzed. These isolates were 98.9% and 98.6% identical in the coding and non-coding regions of RNA-3, and 96.9 and 91.5% identical in the coding and non-coding regions of RNA-4, and are therefore strains of the same virus. There is about three times as much variation between isolates (based on consensus sequences) as there is within isolates (based on sequences of individual clones). There is also considerably more variation for RNA-4 (both between and within isolates) than there is for RNA-3, even though between tenivirus species RNA-3 has diverged more than RNA-4, implying that the evolution of the tenuivirus RNAs is not necessarily dependent on the amount of variation found for these RNAs.