156 resultados para chlorophyll relative index


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OBJECTIVE Streptozotocin (STZ) is the most widely used diabetogenic agent in animal models of islet transplantation. However, the immunomodifying effects of STZ and the ensuing hyperglycemia on lymphocyte subsets, particularly on T regulatory cells (Tregs), remain poorly understood. RESEARCH DESIGN AND METHODS This study evaluated how STZ-induced diabetes affects adaptive immunity and the consequences thereof on allograft rejection in murine models of islet and skin transplantation. The respective toxicity of STZ and hyperglycemia on lymphocyte subsets was tested in vitro. The effect of hyperglycemia was assessed independently of STZ in vivo by the removal of transplanted syngeneic islets, using an insulin pump, and with rat insulin promoter diphtheria toxin receptor transgenic mice. RESULTS Early lymphopenia in both blood and spleen was demonstrated after STZ administration. Direct toxicity of STZ on lymphocytes, particularly on CD8(+) cells and B cells, was shown in vitro. Hyperglycemia also correlated with blood and spleen lymphopenia in vivo but was not lymphotoxic in vitro. Independently of hyperglycemia, STZ led to a relative increase of Tregs in vivo, with the latter retaining their suppressive capacity in vitro. The higher frequency of Tregs was associated with Treg proliferation in the blood, but not in the spleen, and higher blood levels of transforming growth factor-β. Finally, STZ administration delayed islet and skin allograft rejection compared with naive mice. CONCLUSIONS These data highlight the direct and indirect immunosuppressive effects of STZ and acute hyperglycemia, respectively. Thus, these results have important implications for the future development of tolerance-based protocols and their translation from the laboratory to the clinic.

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Selective pressures related to gene function and chromosomal architecture are acting on genome sequences and can be revealed, for instance, by appropriate genometric methods. Cumulative nucleotide skew analyses, i.e., GC, TA, and ORF orientation skews, predict the location of the origin of DNA replication for 88 out of 100 completely sequenced bacterial chromosomes. These methods appear fully reliable for proteobacteria, Gram-positives, and spirochetes as well as for euryarchaeotes. Based on this genome architecture information, coorientation analyses reveal that in prokaryotes, ribosomal RNA (rRNA) genes encoding the small and large ribosomal subunits are all transcribed in the same direction as DNA replication; that is, they are located along the leading strand. This result offers a simple and reliable method for circumscribing the region containing the origin of the DNA replication and reveals a strong selective pressure acting on the orientation of rRNA genes similar to the weaker one acting on the orientation of ORFs. Rate of coorientation of transfer RNA (tRNA) genes with DNA replication appears to be taxon-specific. Analyzing nucleotide biases such as GC and TA skews of genes and plotting one against the other reveals a taxonomic clusterization of species. All ribosomal RNA genes are enriched in Gs and depleted in Cs, the only so far known exception being the rRNA genes of deuterostomian mitochondria. However, this exception can be explained by the fact that in the chromosome of the human mitochondrion, the model of the deuterostomian organelle genome, DNA replication, and rRNA transcription proceed in opposite directions. A general rule is deduced from prokaryotic and mitochondrial genomes: ribosomal RNA genes that are transcribed in the same direction as the DNA replication are enriched in Gs, and those transcribed in the opposite direction are depleted in Gs.

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The relationship between oestrogen replacement treatment and the risk of endometrial cancer was analysed in a case-control study of 158 histologically confirmed incident cases below the age of 75 and 468 controls in hospital for acute, non-neoplastic, non-hormone-related conditions conducted in the Swiss Canton of Vaud in 1988-1992. Overall, 60 (38%) cases vs. 93 (20%) controls had ever used oestrogen replacement treatment: the corresponding multiple logistic regression relative risk (RR) was 2.7 (95% confidence interval, CI: 1.7-4.1). The risk was directly related to duration of use, and rose to 5.1 (95% CI: 2.7-9.8) for > 5 year-use. The RR was still significantly elevated 10 or more years after stopping use (RR = 2.3, 95% CI: 1.2-4.5). When the role of covariates was considered, a significant interaction was observed with body mass index (RR for long-term oestrogen use = 6.0 for lean or normal weight women vs. 2.4 for overweight women). There was also a hint of a negative interaction with oral contraceptive (OC) use, since the RR for oestrogens was higher (or restricted) to women who had never used OC (RR = 5.4, for long-term oestrogen use), as compared with those who had used OC, who showed no significant evidence of association with oestrogens (RR = 0.9 for long-term use). There was no significant interaction with cigarette smoking. Thus, this study confirms the presence of a strong association between oestrogen replacement treatment and endometrial cancer risk, since in the late 1980s or early 1990s about 25% of cases could be attributed to oestrogen replacement treatment in this Swiss population. Further, it confirms the presence of significant negative interactions of oestrogen use with obesity, and, possibly, with OC as well.

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Rapport de synthèse : Le ganglion sentinelle (GS) se défini comme le premier ganglion de la chaîne ganglionnaire qui draine le territoire anatomique où siège une tumeur et, par conséquent, celui ayant le plus de possibilités de recevoir des métastases. La combinaison des deux techniques de détection du GS existantes, lymphoscintigraphie et coloration, permettent de déceler le GS dans 95-100% des cas. Le taux d'attente métastatique du GS varie entre 16 et 21 % des patients. Dans 50 à 87% des cas, le GS est le seul site de métastase et la probabilité de trouver des micro-métastases dans des ganglions appartenant aux relais supérieurs sans atteinte du GS est estimée à moins de 2%. Ces chiffres relèvent l'importance de la détection du GS. L'emploi de cette technique offre de nombreux avantages par rapport à la lymphadénéctomie élective que nous décrirons. Selon Rousseau et al., il existe une probable association entre le statut du GS et la survie de la maladie. Cette interprétation et celles d'autres auteurs soulignent la pertinence clinique du statut du GS dans le mélanome. En ce qui concerne la survie sans maladie (DFS) et la survie globale (OS), aucune différence significative n'a été observée entre les patients ayant subi une résection complète immédiate des ganglions lymphatiques et ceux qui d'abord ont subi une résection chirurgicale et analyse du GS secondaire, suivies par une dissection élective en cas de positivité. L'objectif de cette étude prospective était d'évaluer la pertinence de la positivité tumorale du GS dans l'évaluation des risques de rechute du mélanome. Cette étude a confirmé l'intérêt de la scintigraphie des ganglions lymphatiques (associée à la technique de coloration par bleu et celle de détection par sonde portable) dans l'identification du GS comme approche thérapeutique au stade précoce du mélanome. Elle a montré, en autre, que le statut du GS et l'indice de Breslow sont des facteurs de risque indépendants importants de rechute chez des patients atteints d'un mélanome au stade précoce. La combinaison de ces deux paramètres a permis de créer des groupes de patients à risque de rechute différents qui pourraient conduire à l'adaptation des protocoles de thérapie en fonction de ces risques.

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Une classification simplifiee du genre Colaniella LIKHAREV est proposee: Colaniella ex gr. parva, Colaniella ex gr. lepida, Colaniella ex gr. minima. Elle correspond a la division du taxon en trois groupes morphologiques. La repartition geographique de ce taxon est inventoriée de meme que les environnements sedimentaires et les microfaunes associees. Les nouvelles decouvertes de C. ex gr. parva dans Ie Permien superieur des coupes de Mesagros (ile d'Egine, Grece), d'Emarat (N Elbourz, Iran) et du Wadi Wasil dans les montagnes centrales d'Oman sont decrites en detail. L'importance des Colanielles dans la biostratigraphie du Permien superieur tethysien est analysee et clarifiee au vu des travaux recents et Ie problème des migrations est abordé. A simplified taxonomic classification in 3 groups of the genus Colaniella LIKHAREV is proposed: Colaniella ex gr. parva, Colaniella ex gr. lepida, Colaniella ex gr. minima. The repartition of the eight main Colaniella biofacies is given and the paleogeographic distribution of this genus is presented on a late Permian map configuration. New late Permian localities with Colaniella ex gr. parva have been found: Aegina island (Greece), Emmarat in the northern Alborz (Iran) and Wadi Wasit in the central Oman Mountains. The stratigraphic range of Colaniella ex gr. parva is much longer than previously accepted even by specialists. This range begins in the early Midian (Abadehian) and ends in the late Changhsingian (Dorashamian), very close to the range of the genus. For environmental reasons and slow eastward migration we have apparent shorter ranges in the Eastern part of the Tethyan domain.

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BACKGROUND: Cigarette smoking is associated with lower body mass index (BMI), and a commonly cited reason for unwillingness to quit smoking is a concern about weight gain. Common variation in the CHRNA5-CHRNA3-CHRNB4 gene region (chromosome 15q25) is robustly associated with smoking quantity in smokers, but its association with BMI is unknown. We hypothesized that genotype would accurately reflect smoking exposure and that, if smoking were causally related to weight, it would be associated with BMI in smokers, but not in never smokers. METHODS: We stratified nine European study samples by smoking status and, in each stratum, analysed the association between genotype of the 15q25 SNP, rs1051730, and BMI. We meta-analysed the results (n = 24 198) and then tested for a genotype × smoking status interaction. RESULTS: There was no evidence of association between BMI and genotype in the never smokers {difference per T-allele: 0.05 kg/m(2) [95% confidence interval (95% CI): -0.05 to 0.18]; P = 0.25}. However, in ever smokers, each additional smoking-related T-allele was associated with a 0.23 kg/m(2) (95% CI: 0.13-0.31) lower BMI (P = 8 × 10(-6)). The effect size was larger in current [0.33 kg/m(2) lower BMI per T-allele (95% CI: 0.18-0.48); P = 6 × 10(-5)], than in former smokers [0.16 kg/m(2) (95% CI: 0.03-0.29); P = 0.01]. There was strong evidence of genotype × smoking interaction (P = 0.0001). CONCLUSIONS: Smoking status modifies the association between the 15q25 variant and BMI, which strengthens evidence that smoking exposure is causally associated with reduced BMI. Smoking cessation initiatives might be more successful if they include support to maintain a healthy BMI.

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ABSTRACT: BACKGROUND: There is little information regarding the trends in body mass index (BMI) and obesity in the overall Portuguese population, namely if these trends are similar according to educational level. In this study, we assessed the trends in the prevalence of overweight and obesity in the Portuguese population, overall and by educational level. METHODS: Cross-sectional national health interview surveys conducted in 1995-6 (n=38,504), 1998-9 (n=38,688) and 2005-6 (n=25,348). Data were derived from the population and housing census of 1991 and two geographically-based strata were defined. The sampling unit was the house, and all subjects living in the sampling unit were surveyed. Height and weight were self-reported; the effects of gender, age group and educational level were also assessed by self-reported structured questionnaires. Bivariate comparisons were performed using Chi-square or analysis of variance (ANOVA). Trends in BMI levels were assessed by linear regression analysis, while trends in the prevalence of obesity were assessed by logistic regression. RESULTS: Mean (+/-standard deviation) BMI increased from 25.2+/-4.0 in 1995-6 to 25.7+/-4.5 kg/m2 in 2005-6. Prevalence of overweight remained stable (36.1% in 1995-6 and 36.4% in 2005) while prevalence of obesity increased (11.5% in 1995-6 and 15.1% in 2005-6). Similar findings were observed according to age group. Mean age-adjusted BMI increase (expressed in kg/m2/year and 95% confidence interval) was 0.073 (0.062, 0.084), 0.016 (0.000, 0.031) and 0.073 (0.049, 0.098) in men with primary, secondary and university levels, respectively; the corresponding values in women were 0.085 (0.073, 0.097), 0.052 (0.035, 0.069) and 0.062 (0.038, 0.084). Relative to 1995-6, obesity rates increased by 48%, 41% and 59% in men and by 40%, 75% and 177% in women with primary, secondary and university levels, respectively. The corresponding values for overweight were 6%, 1% and 23% in men and 5%, 7% and 65% in women. CONCLUSION: Between 1995 and 2005, obesity increased while overweight remained stable in the adult Portuguese population. Although higher rates were found among lesser educated subjects, the strong increase in BMI and obesity levels in highly educated subjects is of concern.

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INTRODUCTION: Lumbar spinal stenosis (LSS) treatment is based primarily on the clinical criteria providing that imaging confirms radiological stenosis. The radiological measurement more commonly used is the dural sac cross-sectional area (DSCA). It has been recently shown that grading stenosis based on the morphology of the dural sac as seen on axial T2 MRI images, better reflects severity of stenosis than DSCA and is of prognostic value. This radiological prospective study investigates the variability of surface measurements and morphological grading of stenosis for varying degrees of angulation of the T2 axial images relative to the disc space as observed in clinical practice. MATERIALS AND METHODS: Lumbar spine TSE T2 three-dimensional (3D) MRI sequences were obtained from 32 consecutive patients presenting with either suspected spinal stenosis or low back pain. Axial reconstructions using the OsiriX software at 0°, 10°, 20° and 30° relative to the disc space orientation were obtained for a total of 97 levels. For each level, DSCA was digitally measured and stenosis was graded according to the 4-point (A-D) morphological grading by two observers. RESULTS: A good interobserver agreement was found in grade evaluation of stenosis (k = 0.71). DSCA varied significantly as the slice orientation increased from 0° to +10°, +20° and +30° at each level examined (P < 0.0001) (-15 to +32% at 10°, -24 to +143% at 20° and -29 to +231% at 30° of slice orientation). Stenosis definition based on the surface measurements changed in 39 out of the 97 levels studied, whereas the morphology grade was modified only in two levels (P < 0.01). DISCUSSION: The need to obtain continuous slices using the classical 2D MRI acquisition technique entails often at least a 10° slice inclination relative to one of the studied discs. Even at this low angulation, we found a significantly statistical difference between surface changes and morphological grading change. In clinical practice, given the above findings, it might therefore not be necessary to align the axial cuts to each individual disc level which could be more time-consuming than obtaining a single series of axial cuts perpendicular to the middle of the lumbar spine or to the most stenotic level. In conclusion, morphological grading seems to offer an alternative means of assessing severity of spinal stenosis that is little affected by image acquisition technique.

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BACKGROUND: Studies about the association between body mass index (BMI) and health-related quality of life (HRQOL) are often limited, because they 1) did not include a broad range of health-risk behaviors as covariates; 2) relied on clinical samples, which might lead to biased results; and 3) did not incorporate underweight individuals. Hence, this study aims to examine associations between BMI (from being underweight through obesity) and HRQOL in a population-based sample, while considering multiple health-risk behaviors (low physical activity, risky alcohol consumption, daily cigarette smoking, frequent cannabis use) as well as socio-demographic characteristics. METHODS: A total of 5 387 young Swiss men (mean age = 19.99; standard deviation = 1.24) of a cross-sectional population-based study were included. BMI was calculated (kg/m²) based on self-reported height and weight and divided into 'underweight' (<18.5), 'normal weight' (18.5-24.9), 'overweight' (25.0-29.9) and 'obese' (≥30.0). Mental and physical HRQOL was assessed via the SF-12v2. Self-reported information on physical activity, substance use (alcohol, cigarettes, and cannabis) and socio-demographic characteristics also was collected. Logistic regression analyses were conducted to study the associations between BMI categories and below average mental or physical HRQOL. Substance use variables and socio-demographic variables were used as covariates. RESULTS: Altogether, 76.3% were normal weight, whereas 3.3% were underweight, 16.5% overweight and 3.9% obese. Being overweight or obese was associated with reduced physical HRQOL (adjusted OR [95% CI] = 1.58 [1.18-2.13] and 2.45 [1.57-3.83], respectively), whereas being underweight predicted reduced mental HRQOL (adjusted OR [95% CI] = 1.49 [1.08-2.05]). Surprisingly, obesity decreased the likelihood of experiencing below average mental HRQOL (adjusted OR [95% CI] = 0.66 [0.46-0.94]). Besides BMI, expressed as a categorical variable, all health-risk behaviors and socio-demographic variables were associated with reduced physical and/or mental HRQOL. CONCLUSIONS: Deviations from normal weight are, even after controlling for important health-risk behaviors and socio-demographic characteristics, associated with compromised physical or mental HRQOL among young men. Hence, preventive programs should aim to preserve or re-establish normal weight. The self-appraised positive mental well-being of obese men noted here, which possibly reflects a response shift, might complicate such efforts.

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OBJECTIVE: Evaluation of a French translation of the Addiction Severity Index (ASI) in 100 (78 male) alcoholic patients. METHOD: Validity of the instrument was assessed by measuring test-retest and interrater reliability, internal consistency and convergence and discrimination between items and scales. Concurrent validity was assessed by comparing the scores from the ASI with those obtained from three other clinimetric instruments. RESULTS: Test-retest reliability of ASI scores (after a 10-day interval) was good (r = 0.63 to r = 0.95). Interrater reliability was evaluated using six video recordings of patient interviews. Severity ratings assigned by six rates were significantly different (p < .05), but 72% of the ratings assigned by those who viewed the videos were within two points of the interviewer's severity ratings. Cronbach alpha coefficient of internal consistency varied from 0.58 to 0.81 across scales. The average item-to-scale convergent validity (r value) was 0.49 (range 0.0 to 0.84) for composite scores and 0.35 (range 0.00 to 0.68) for severity ratings, whereas discriminant validity was 0.11 on average (range-0.19 to 0.46) for composite scores and 0.12 (range-0.20 to 0.52) for severity ratings. Finally, concurrent validity with the following instruments was assessed: Severity of Alcoholism Dependence Questionnaire (40% shared variance with ASI alcohol scale), Michigan Alcoholism Screening Test (2% shared variance with ASI alcohol scale) and Hamilton Depression Rating Scale (31% shared variance with ASI psychiatric scale). CONCLUSIONS: The Addiction Severity Index covers a large scope of problems encountered among alcoholics and quantifies need for treatment. This French version presents acceptable criteria of reliability and validity.

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This study aimed to derive an index quantifying the state of alteration of cadavers by quantifying the presence of gas in the body using postmortem multidetector computed tomography (MDCT) imaging, and to validate the index by defining its sensitivity and specificity. The RA (radiological alteration)-index was derived from postmortem MDCT data from 118 nontraumatically deceased people. To validate the index, 100 additional scanned bodies (50 % traumatically deceased) were retrospectively examined by two independent observers. Presence of gas at 82 sites was assessed by a radiologist, whereas a forensic pathologist only investigated the seven sites used for the RA-index. The RA-index was highly correlated to the overall presence of gas in all 82 sites (R(2) = 0.98 in the derivation set and 0.85 in the validation set). Semiquantitative evaluation of gas presence in each site showed moderate reliability (Cohen's kappa range, 0.41-0.78); nevertheless, the overall RA-index was very reliable (ICC(2,1) = 0.95; 95 % CI 0.92-0.96). Examiner using the RA-index detected heart cavities full of gas with a sensitivity of 100 % (95 % CI 51.7-100) and a specificity of 98.8 % (92.6-99.9). We conclude that determining the presence of gas at seven sites is a valid means to measure the distribution of gas due to cadaveric alteration in the entire body. The RA-index is rapid, easy-to-use, and reliable for nonexperienced users, and it is a valid method to suspect the normal presence of gas from cadaveric alteration. MDCT can be used to screen for gas embolism and to give indications for gas composition analysis (gas chromatography).

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Background and Aims: The international E EsAI s tudy g roup is currently d eveloping the first activity index ( EEsAI) specific for E osinophilic Esophagitis (EoE). G oal: T o develop, e valuate and validate the EEsAI. Methods: T he development c omprises three p hases: 1. Selection of c andidate items ( completed); 2. Evaluation of t he activity index i n a first patient cohort (in progress, p atient recruitment completed); and 3. Validation in a s econd EoE patient cohort. F ocus group interviews with patients were used in p hase 1 to g enerate patient r eported outcomes (PRO) according to g uidelines o f regulatory authorities (FDA a nd EMA), whereas the section of biologic items was developed by Delphi rounds o f international E oE experts from E urope and North America. Results: T he EEsAI has a modular c omposition to a ssess the following components o f EoE activity: p atient r eported outcomes, e ndoscopic activity, histologic activity, laboratory activity, a nd quality of l ife (QoL). Definitions for a ll aspects o f endoscopic and histologic appearance were e stablished by consensus r ounds a mong E oE experts. S ymptom a ssessment tools were c reated that t ake into account d ifferent food consistencies as w ell as f ood avoidance and specific processing strategies. The EEsAI i s currently e valuated in a cohort of a dult EoE patients since M arch 2 011 (patient recruitment completed). Conclusions: The EEsAI standardizes outcome assessment in EoE t rials. T he collaboration with i nternational E oE e xperts a s well as f ollowing o f the guidelines f rom regulatory authorities will lead to its wide applicability.