RESUMEN
The investigation dealt with the effect of the replacement of a part of wheat flour by pea flour on the properties of batters and cakes. As the protein composition of pea flour differs from that of wheat, the effect of its incorporation on batter formation and cake properties was monitored throughout the different steps of cake processing. The incorporation of air, which influences the cell structure and density of the cake, was the subject of particular attention. Four orders of incorporation were first investigated to identify their effects on a standard recipe made with 100% wheat flour. Mixing first egg and sugar together allows introducing air, but most of it is lost after oil and flour introduction. Whatever the order of incorporation, the density of the batter ends around 1.1 ± 0.2 g.cm-1. However, batter consistencies are significantly different and resulting cakes show different crumb structures. These results are discussed in terms of physicochemical mechanisms, and a schematic representation of the phenomena occurring at the different steps of mixing depending on the order of ingredient incorporation is proposed. When 20 and 40% of the wheat flour was replaced by pea flour using the two most energy-efficient orders of incorporation, more air was incorporated into the batter. However, the resulting cakes were denser, but surprisingly softer. Differences in cell structure explain this apparent contradiction.
RESUMEN
The Golden Retriever Muscular Dystrophy dog lacks dystrophin. Disease progression in this model shares many similarities with the Duchenne muscular dystrophy, both from anatomico pathological and clinical standpoints. The model is increasingly used in pre-clinical trials but needs to be further investigated, particularly with reference to the evaluation of therapies. The aim of this study was to identify quantitative indices that would help characterize the dystrophic dog non-invasively using NMR imaging. Two-month-old dystrophic dogs and healthy control animals were scanned at 4T. Standard T2- and T1-weighted images, fat-saturated T1-weighted images pre- and post-gadolinium chelate injection were acquired and kinetics of muscle enhancement were studied over a 2-h period. Several indices were found to be abnormally high in dystrophic dogs: the T2-weighted/T1-weighted signal ratio, T2-weighted image heterogeneity and maximal signal enhancement post-gadolinium. These may be proposed to evaluate muscle structural alterations non-invasively in this disease.
Asunto(s)
Espectroscopía de Resonancia Magnética , Músculo Esquelético/patología , Distrofia Muscular Animal/diagnóstico , Animales , Modelos Animales de Enfermedad , Perros , Masculino , Factores de TiempoRESUMEN
A 15-Country collaborative cohort study was conducted to provide direct estimates of cancer risk following protracted low doses of ionizing radiation. Analyses included 407,391 nuclear industry workers monitored individually for external radiation and 5.2 million person-years of follow-up. A significant association was seen between radiation dose and all-cause mortality [excess relative risk (ERR) 0.42 per Sv, 90% CI 0.07, 0.79; 18,993 deaths]. This was mainly attributable to a dose-related increase in all cancer mortality (ERR/Sv 0.97, 90% CI 0.28, 1.77; 5233 deaths). Among 31 specific types of malignancies studied, a significant association was found for lung cancer (ERR/Sv 1.86, 90% CI 0.49, 3.63; 1457 deaths) and a borderline significant (P = 0.06) association for multiple myeloma (ERR/Sv 6.15, 90% CI <0, 20.6; 83 deaths) and ill-defined and secondary cancers (ERR/Sv 1.96, 90% CI -0.26, 5.90; 328 deaths). Stratification on duration of employment had a large effect on the ERR/Sv, reflecting a strong healthy worker survivor effect in these cohorts. This is the largest analytical epidemiological study of the effects of low-dose protracted exposures to ionizing radiation to date. Further studies will be important to better assess the role of tobacco and other occupational exposures in our risk estimates.
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Industrias/estadística & datos numéricos , Neoplasias Inducidas por Radiación/mortalidad , Reactores Nucleares/estadística & datos numéricos , Enfermedades Profesionales/mortalidad , Exposición Profesional/estadística & datos numéricos , Medición de Riesgo/métodos , Recuento Corporal Total/estadística & datos numéricos , Adulto , Estudios de Cohortes , Empleo/estadística & datos numéricos , Femenino , Humanos , Cooperación Internacional , Masculino , Dosis de Radiación , Factores de Riesgo , Análisis de Supervivencia , Tasa de SupervivenciaRESUMEN
We investigated whether the nitric oxide (NO) synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) affects the cerebrovascular changes occurring in seizures induced by kainic acid (KA) in awake, spontaneously breathing rats. Blood flow and tissue PO2 and PCO2 were continuously and simultaneously measured by mass spectrometry from a cannula chronically implanted into the dorsal hippocampus, L-NAME (20 mg/kg; n = 8) or saline (n = 9) was administered i.p. 30 min prior to i.p. KA (10 mg/kg) injection. L-NAME significantly decreased hippocampal blood flow and PO2 and increased mean arterial blood pressure (MABP). In L-NAME-treated rats, seizure activity occurred about 10 min sooner than in control rats, and status epilepticus was inevitably followed by a flat electroencephalogram and sudden death. In contrast, control rats survival KA-induced seizures. Hippocampal blood flow was significantly less elevated during the seizures in L-NAME-treated rats than in control rats (maximal levels, 170 and 450%, respectively, of baseline values), though MABP remained significantly higher. Hippocampal PO2 was significantly decreased at all times after KA injection in L-NAME-treated rats, whereas it remained at or above normoxic levels in control rats. The present results show that L-NAME markedly attenuates the hippocampal blood flow and tissue PO2 changes in response to enhanced metabolic activity due to limbic seizures and suggest that NO is of major importance in cerebral blood flow control during KA-induced seizures.
Asunto(s)
Hipocampo/irrigación sanguínea , Hiperemia/etiología , Hiperemia/prevención & control , Óxido Nítrico/antagonistas & inhibidores , Convulsiones/complicaciones , Animales , Arginina/análogos & derivados , Arginina/farmacología , Conducta Animal/efectos de los fármacos , Temperatura Corporal/efectos de los fármacos , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/fisiopatología , Circulación Cerebrovascular/efectos de los fármacos , Electroencefalografía , Hiperemia/fisiopatología , Ácido Kaínico/farmacología , Masculino , NG-Nitroarginina Metil Éster , Óxido Nítrico/biosíntesis , Ratas , Ratas Wistar , Convulsiones/inducido químicamente , Convulsiones/fisiopatologíaRESUMEN
Hepatitis C virus (HCV) strains isolated from 68 haemodialysis Tunisian patients exhibiting chronic infection were genotyped targeting the NS5b region of the HCV genome using a prototype assay developed by Bayer HealthCare-Diagnostics (TRUGENE NS5b HCV). The overall results were compared to those obtained with another assay of the same company based on sequencing of the 5' non-coding region (TRUGENE HCV 5'NC genotyping kit). All strains could be typed by the 5'NC typing kit, but only 62 (91; 2%) by the NS5b prototype assay. All the 62 strains typed by both methods exhibited the same pattern at the type level: 57 were type 1, 3 were type 2, and 2 were type 4. At the subtype level, eight strains that gave undetermined results by the 5'NC kit were successfully typed by the NS5b kit; eight additional strains exhibited discrepant results. The overall agreement between the two assays was 74.2% at the subtype level. In conclusion, the NS5b region appears to be much more accurate than the 5'NC region to subtype HCV strains, especially in those isolated from patients attending haemodialysis centres where the subtype distribution suggests frequent nosocomial transmissions.
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Regiones no Traducidas 5'/análisis , Hepacivirus/clasificación , Juego de Reactivos para Diagnóstico , Proteínas no Estructurales Virales/análisis , Regiones no Traducidas 5'/química , Estudios de Evaluación como Asunto , Genotipo , Hepacivirus/genética , Humanos , Túnez , Proteínas no Estructurales Virales/químicaRESUMEN
It has been suggested that nitric oxide (NO) interferes with both glutamatergic neurotransmission and the regulation of cerebral blood flow in epileptic seizures. This study examines the effect of an inhibitor of NO synthesis, NG-nitro-L-arginine methyl ester (L-NAME, 20 mg/kg), on the extracellular concentration of glutamate during seizures induced by kainic acid (KA; 10 mg/kg), both drugs being administered systemically. L-NAME was injected 40 min before KA. The extracellular glutamate concentration was measured in the hippocampus of awake, spontaneously breathing rats using microdialysis combined with HPLC. The arterial blood gases and glycemia were periodically checked. The arterial blood pressure, the electrocorticogram and the body temperature were continuously monitored. In basal conditions, the systemic injection of L-NAME increased arterial blood pressure but did not significantly change the hippocampal glutamate level. In seizure conditions, the hippocampal glutamate concentration was either slightly increased or not significantly changed in saline-treated rats (n = 6) but it was decreased in L-NAME-treated rats (n = 6). At all times after KA injection, the hippocampal glutamate concentration was significantly lower in L-NAME-treated rats than in saline-treated rats. Unlike saline-treated rats, L-NAME-treated rats died during status epilepticus. This study shows that acute systemic injection of L-NAME reduces the extracellular concentration of glutamate in the rat hippocampus during seizures induced by KA.
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Arginina/análogos & derivados , Ácido Glutámico/metabolismo , Óxido Nítrico/antagonistas & inhibidores , Animales , Arginina/farmacología , Glucemia/efectos de los fármacos , Modelos Animales de Enfermedad , Electrofisiología , Hipocampo , Ácido Kaínico/farmacología , Masculino , NG-Nitroarginina Metil Éster , Óxido Nítrico/biosíntesis , Ratas , Ratas Wistar , Convulsiones/inducido químicamente , Factores de TiempoRESUMEN
BACKGROUND AND PURPOSE: DTI is a promising technique for imaging of the spinal cord, but the technique has susceptibility-induced artifacts. We evaluated a pulse-triggered DTI sequence with an rFOV technique and coronal acquisition for the assessment of the cervical spinal cord in patients with myelitis at 3T. MATERIALS AND METHODS: A rFOV acquisition was established by a noncoplanar application of the excitation and the refocusing pulse in conjunction with outer volume suppression. The DTI sequence was performed in the coronal plane in 12 healthy volunteers and 40 consecutive patients with myelitis. Probabilistic tractography of the posterior and lateral funiculi was performed from the C1 to C7 levels. FA, MD, aD, rD, and ratios of aD and rD were measured. RESULTS: In healthy volunteers, mean DTI indices within the whole-fiber pathways were the following: FA = 0.61, MD = 1.17 × 10(-3) mm(2)/s, aD = 1.96 × 10(-3) mm(2)/s, rD = 0.77 × 10(-3) mm(2)/s, and ratios of aD and rD = 2.5. Comparison of healthy controls and patients with myelitis identified statistically significant differences for all DTI parameters. Different patterns of myelitis, including spinal cord atrophy and active inflammatory lesions, were recognized. There was a significant correlation between clinical severity and DTI parameters. CONCLUSIONS: The present work introduces a new approach for DTI of the cervical spinal cord at 3T, enabling a quantitative follow-up of patients with myelitis.
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Algoritmos , Vértebras Cervicales/patología , Imagen de Difusión Tensora/métodos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Mielitis/patología , Adulto , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
OBJECTIVES: To provide direct estimates of risk of cancer after protracted low doses of ionising radiation and to strengthen the scientific basis of radiation protection standards for environmental, occupational, and medical diagnostic exposures. DESIGN: Multinational retrospective cohort study of cancer mortality. SETTING: Cohorts of workers in the nuclear industry in 15 countries. PARTICIPANTS: 407 391 workers individually monitored for external radiation with a total follow-up of 5.2 million person years. MAIN OUTCOME MEASUREMENTS: Estimates of excess relative risks per sievert (Sv) of radiation dose for mortality from cancers other than leukaemia and from leukaemia excluding chronic lymphocytic leukaemia, the main causes of death considered by radiation protection authorities. RESULTS: The excess relative risk for cancers other than leukaemia was 0.97 per Sv, 95% confidence interval 0.14 to 1.97. Analyses of causes of death related or unrelated to smoking indicate that, although confounding by smoking may be present, it is unlikely to explain all of this increased risk. The excess relative risk for leukaemia excluding chronic lymphocytic leukaemia was 1.93 per Sv (< 0 to 8.47). On the basis of these estimates, 1-2% of deaths from cancer among workers in this cohort may be attributable to radiation. CONCLUSIONS: These estimates, from the largest study of nuclear workers ever conducted, are higher than, but statistically compatible with, the risk estimates used for current radiation protection standards. The results suggest that there is a small excess risk of cancer, even at the low doses and dose rates typically received by nuclear workers in this study.
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Neoplasias Inducidas por Radiación/mortalidad , Enfermedades Profesionales/mortalidad , Relación Dosis-Respuesta a Droga , Métodos Epidemiológicos , Femenino , Humanos , Masculino , Centrales Eléctricas , Medición de Riesgo , Recursos HumanosRESUMEN
The agglutination percentages given by various erythrocytes with reference sera have been compared in blood samples from Kulamwos living in the Ivory Coast and of blood donors of the regional transfusion centre of Toulouse. The study of O, A, B and AB phenotypes shows: 1. in O Kulamwos a higher agglutination percentage with anti-H than in Toulousains; 2. in B Kulamwos a higher agglutination percentage with anti-B than in Toulousains; 3. in A Kulamwos a very marked frequency of A intermediate which can be classified in different categories due to the variability of their agglutination percentage with anti-A1 and anti-H sera.
Asunto(s)
Sistema del Grupo Sanguíneo ABO , Donantes de Sangre , Côte d'Ivoire , Agregación Eritrocitaria , HumanosRESUMEN
Agglutination percentages of red blood cells from European and from three African populations (Twareg from Mali, Sara from Central African Republic, and Niokholonko from Senegal) in the ABO system have been compared. The results show a greater agglutinability of group O erythrocytes with anti-H sera, for African subjects than for Europeans. No significant difference was noted between African and European B subjects, except for the Niokholonko, whose agglutination percentage was slightly higher with anti-B. The study of group A disclosed a large number of Aint in all African populations studied. The AB African red cells seem to be less agglutinable with anti-A and anti-A1 sera than European ones; A and A1 antigens may be depressed by a strong B antigen.
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Sistema del Grupo Sanguíneo ABO , Población Negra , Frecuencia de los Genes , Población Blanca , África , Femenino , Humanos , Masculino , FenotipoRESUMEN
An automatized technique for the study of hemagglutination kinetics is described. It was used to differentiate between homozygous and heterozygous individuals in the Rh system. Other applications are proposed.
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Pruebas de Hemaglutinación/instrumentación , Sistema del Grupo Sanguíneo Rh-Hr/clasificación , Sistema del Grupo Sanguíneo ABO/análisis , Automatización , Heterocigoto , Homocigoto , Humanos , CinéticaRESUMEN
The authors determined the agglutination percentages with anti-B, eel and Ulex europeus anti-H reagents for the kinetic study of the in vitro conversion O red blood cells in B. The agglutination with the anti-B increases in proportion as the agglutination with eel anti-H decreases; the agglutination with Ulex anti-H remains constant. They converted (time=18 h) O red blood cells with a more or less high substance H content (adults in good health, africans and europeans, patients, newborn and one "Bombay" phenotype). They showed that there is a good correlation between the agglutination percentages with eel anti-H or Ulex anti-H before conversion and the agglutination percentages with anti-B after conversion. These "O converted" look like the B phenotype defined by a check sample of B subjects.
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Sistema del Grupo Sanguíneo ABO , Galactosiltransferasas/farmacología , Adulto , Eritrocitos/metabolismo , Pruebas de Hemaglutinación , Humanos , Recién Nacido , Cinética , Factores de TiempoRESUMEN
The red blood cell antigens of the ABO system are not present in all the anthropïd Primates. The Chimpanzee, particularly, shows only the two genes A and O. The alpha-galactosyl transferase, present in the human sera of group B, has been used to fix a molecule of galactose on O red cells of Chimpanzee giving them a B specificity. If the B gene was present in the Chimpanzee it could consequently be expressed on the erythrocytes. This gene, probably present in an ancestor common to the anthropoïd apes and to Man disappeared in the Chimpanzee, perhaps at the origin of species.
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Sistema del Grupo Sanguíneo ABO , Galactosiltransferasas/sangre , Pan troglodytes/sangre , Animales , Galactosemias , Genes , Pruebas de Hemaglutinación , Humanos , Técnicas In Vitro , FilogeniaRESUMEN
The authors have selected three series of families presenting several heterozygous AB gene combinations: the same gene A and the same gene B; the same gene B and different genes A; and the same gene A and different genes B. The results concerning these families show that the quantitiy of A1 and A substances (for A1B) or A (for A2B) is related to the "quality" of the alpha-D-galactosyl transferase acting on a more or less important H substratum. The alpha-N-acetyl-D-galactosaminyl transferase seems to have a minor function.
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Sistema del Grupo Sanguíneo ABO , Alelos , Heterocigoto , Pruebas de Aglutinación , Galactosiltransferasas/metabolismo , Pruebas Genéticas , Humanos , Linaje , FenotipoRESUMEN
Determination of hepatitis C virus (HCV) genotypes and subtypes has become increasingly important for the clinical management and prognosis of HCV infections. The aim of the present study was to assess the specificity and reliability of a newly developed, commercially available HCV genotyping kit (TRUGENE HCV 5'NC genotyping kit). This technique utilizes PCR fragments previously generated by the diagnostic Roche AMPLICOR HCV test, which are subsequently subjected to simultaneous PCR amplification and direct sequencing (CLIP sequencing) of the 5' noncoding region (5'NCR). HCV isolates from 100 randomly chosen patients were genotyped by both the TRUGENE HCV 5'NC genotyping kit and DNA enzyme immunoassay (DEIA). Typing results obtained by both methods were in complete concordance in 91% of the cases. HCV RNA from the samples with discordant genotype assignment in both assays was additionally amplified with primers from the HCV core and NS5B regions. Phylogenetic analysis of the obtained sequences supported the results obtained from DEIA in six cases and CLIP sequencing in two cases. In the former six cases, the TRUGENE HCV 5'NC genotyping kit could not correctly differentiate between subtypes of genotypes 1 and 2 due to the high conservation of the 5'NCR. However, since there was not any misclassification between HCV genotypes 1 and non-1 types, the results obtained with this system are, in general, reliable and can be used in clinical practice. The TRUGENE HCV 5'NC genotyping kit in our hands proved to be a fast and convenient technique that might be an attractive option for HCV genotyping in laboratories already using the Roche AMPLICOR HCV test for diagnostic reverse transcription-PCR.