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991.
992.
Evguenia Krastinova Remonie Seng Patrick Yeni Jean-Paul Viard Daniel Vittecoq Caroline Lascoux-Combe Erwan Fourn Golriz Pahlavan Jean Fran?ois Delfraissy Laurence Meyer for the ANRS PRIMO COPANA Cohorts 《PloS one》2013,8(8)
Objective
Guidelines for initiating HIV treatment are regularly revised. We explored how physicians in France have applied these evolving guidelines for ART initiation over the last decade in two different situations: chronic (CHI) and primary HIV-1 infection (PHI), since specific recommendations for PHI are also provided in France.Methods
Data came from the ANRS PRIMO (1267 patients enrolled during PHI in 1996–2010) and COPANA (800 subjects enrolled at HIV diagnosis in 2004–2008) cohorts. We defined as guidelines-inconsistent during PHI and CHI, patients meeting criteria for ART initiation and not treated in the following month and during the next 6 months, respectively.Results
ART initiation during PHI dramatically decreased from 91% of patients in 1996–99 to 22% in 2007 and increased to 60% in 2010, following changes in recommendations. In 2007, however, after the CD4 count threshold was raised to 350 cells/mm3 in 2006, only 55% of the patients with CD4≤350 were treated and 66% in 2008. During CHI, ART was more frequently initiated in patients who met the criteria at entry (96%) than during follow-up: 83% when recommendation to treat was 200 and 73% when it was 350 cells/mm3. Independent risk factors for not being treated during CHI despite meeting the criteria were lower viral load, lower educational level, and poorer living conditions.Conclusion
HIV ART initiation guidelines are largely followed by practitioners in France. What can still be improved, however, is time to treat when CD4 cell counts reach the threshold to treat. Risk factors for lack of timely treatment highlight the need to understand better how patients’ living conditions and physicians’ perceptions influence the decision to initiate treatment. 相似文献993.
Sophie Sanchez Vincent Dupret Paul Tafforeau Katherine M. Trinajstic Bettina Ryll Pierre-Jean Gouttenoire Lovisa Wretman Louise Zylberberg Fran?oise Peyrin Per E. Ahlberg 《PloS one》2013,8(2)
Background
Firm attachments binding muscles to skeleton are crucial mechanical components of the vertebrate body. These attachments (entheses) are complex three-dimensional structures, containing distinctive arrangements of cells and fibre systems embedded in the bone, which can be modified during ontogeny. Until recently it has only been possible to obtain 2D surface and thin section images of entheses, leaving their 3D histology largely unstudied except by extrapolation from 2D data. Entheses are frequently preserved in fossil bones, but sectioning is inappropriate for rare or unique fossil material.Methodology/Principal Findings
Here we present the first non-destructive 3D investigation, by propagation phase contrast synchrotron microtomography (PPC-SRµCT), of enthesis histology in extant and fossil vertebrates. We are able to identify entheses in the humerus of the salamander Desmognathus from the organization of bone-cell lacunae and extrinsic fibres. Statistical analysis of the lacunae differentiates types of attachments, and the orientation of the fibres, reflect the approximate alignment of the muscle. Similar histological structures, including ontogenetically related pattern changes, are perfectly preserved in two 380 million year old fossil vertebrates, the placoderm Compagopiscis croucheri and the sarcopterygian fish Eusthenopteron foordi.Conclusions/Significance
We are able to determine the position of entheses in fossil vertebrates, the approximate orientation of the attached muscles, and aspects of their ontogenetic histories, from PPC-SRµCT data. Sub-micron microtomography thus provides a powerful tool for studying the structure, development, evolution and palaeobiology of muscle attachments. 相似文献994.
Lorenzo Tancioni Tommaso Russo Stefano Cataudella Valentina Milana Anne Kathrin Hett Elisa Corsi Anna Rita Rossi 《PloS one》2013,8(4)
Leuciscine fishes represent an important component of freshwater ichthyofauna endemic to northern Mediterranean areas. This lineage shows high intra-specific morphological variability and exhibits high levels of hybridization, two characteristics that contribute to systematic uncertainties, misclassification of taxa and, potentially, the mismanagement of biodiversity. This study focused on brook chub, Squalius lucumonis, an endemic taxon of Central Italy. The taxonomic status of this species has long been questioned, and a hybrid origin from sympatric leusciscines (S. squalus x Rutilus rubilio, or S. squalus x Telestes muticellus) has been hypothesised. A phenotypic (evaluating shape and meristic counts) and genetic (using mitochondrial and nuclear markers) investigation of these four taxa was conducted to test species delimitation in sympatric areas and to evaluate the taxonomic status of S. lucumonis. One hundred and forty-five individuals of all four taxa were collected within streams of the lowest portion of the Tiber River basin and analysed; this region encompasses a large portion of the S. lucumonis distribution. The different morphological and genetic approaches were individually examined, compared, and then combined in a quantitative model to both investigate the limits of each approach and to identify cases of misclassification. The results obtained confirm the cladogenetic non-hybrid origin of S. lucumonis, highlight the need for immediate conservation actions and emphasise the value of an integrated approach in the study of leuciscines evolution. 相似文献
995.
Pauline Scherdel Jean-Fran?ois Salaün Marie-No?lle Robberecht-Riquet Laura Reali Gabriella Páll Elke J?ger-Roman Manuel Praena Crespo Marilena Moretto Margareta Seher-Zupan?i? Sigurlaug Agustsson the European Confederation of Primary Care Paediatricians research group Martin Chalumeau 《PloS one》2013,8(8)
Objective
We aimed to study current practices in growth monitoring by European primary care paediatricians and to explore their perceived needs in this field.Methods
We developed a cross-sectional, anonymous on-line survey and contacted primary care paediatricians listed in national directories in the 18 European countries with a confederation of primary care paediatricians. Paediatricians participated in the survey between April and September 2011.Results
Of the 1,198 paediatricians from 11 European countries (response rate 13%) who participated, 29% used the 2006 World Health Organization Multicentre Growth Reference Study growth charts, 69% used national growth charts; 61% used software to draw growth charts and 79% did not use a formal algorithm to detect abnormal growth on growth charts. Among the 21% of paediatricians who used algorithms, many used non-algorithmic simple thresholds for height and weight and none used the algorithms published in the international literature. In all, 69% of paediatricians declared that a validated algorithm to monitor growth would be useful in daily practice. We found important between-country variations.Conclusion
The varied growth-monitoring practices declared by primary care paediatricians reveals the need for standardization and evidence-based algorithms to define abnormal growth and the development of software that would use such algorithms. 相似文献996.
Stochastic winter weather events are predicted to increase in occurrence and amplitude at northern latitudes and organisms are expected to cope through phenotypic flexibility. Small avian species wintering in these environments show acclimatization where basal metabolic rate (BMR) and maximal thermogenic capacity (MSUM) are typically elevated. However, little is known on intra-seasonal variation in metabolic performance and on how population trends truly reflect individual flexibility. Here we report intra-seasonal variation in metabolic parameters measured at the population and individual levels in black-capped chickadees (
Poecile
atricapillus
). Results confirmed that population patterns indeed reflect flexibility at the individual level. They showed the expected increase in BMR (6%) and MSUM (34%) in winter relative to summer but also, and most importantly, that these parameters changed differently through time. BMR began its seasonal increase in November, while MSUM had already achieved more than 20% of its inter-seasonal increase by October, and declined to its starting level by March, while MSUM remained high. Although both parameters co-vary on a yearly scale, this mismatch in the timing of variation in winter BMR and MSUM likely reflects different constraints acting on different physiological components and therefore suggests a lack of functional link between these parameters. 相似文献
997.
998.
Anne Grundy Johanna M. Schuetz Agnes S. Lai Rozmin Janoo-Gilani Stephen Leach Igor Burstyn Harriet Richardson Angela Brooks-Wilson John J. Spinelli Kristan J. Aronson 《Cancer epidemiology》2013,37(5):606-612
Circadian (clock) genes have been linked with several functions relevant to cancer, and epidemiologic research has suggested relationships with breast cancer risk for variants in NPAS2, CLOCK, CRY2 and TIMELESS. Increased breast cancer risk has also been observed among shift workers, suggesting potential interactions in relationships of circadian genes with breast cancer. Relationships with breast cancer of 100 SNPs in 14 clock-related genes, as well as potential interactions with shift work history, were investigated in a case–control study (1042 cases, 1051 controls). Odds ratios in an additive genetic model for European-ancestry participants (645 cases, 806 controls) were calculated, using a two-step correction for multiple testing: within each gene through permutation testing (10,000 permutations), and correcting for the false discovery rate across genes. Interactions of genotypes with ethnicity and shift work (<2 years vs ≥2 years) were evaluated individually. Following permutation analysis, two SNPs (rs3816360 in ARNTL and rs11113179 in CRY1) displayed significant associations with breast cancer and one SNP (rs3027188 in PER1) was marginally significant; however, none were significant following adjustment for the false discovery rate. No significant interaction with shift work history was detected. If shift work causes circadian disruption, this was not reflected in associations between clock gene variants and breast cancer risk in this study. Larger studies are needed to assess interactions with longer durations (>30 years) of shift work that have been associated with breast cancer. 相似文献
999.
Furha Iram Cossor Lucile L. Adams-Campbell Rowan T. Chlebowski Marc J. Gunter Karen Johnson Robert E. Martell Anne McTiernan Michael S. Simon Thomas Rohan Robert B. Wallace Jessica K. Paulus 《Cancer epidemiology》2013,37(5):742-749
Background: Observational studies have associated metformin use with lower colorectal cancer (CRC) incidence but few studies have examined metformin's influence on CRC survival. We examined the relationships among metformin use, diabetes, and survival in postmenopausal women with CRC in the Women's Health Initiative (WHI) clinical trials and observational study. Methods: 2066 postmenopausal women with CRC were followed for a median of 4.1 years, with 589 deaths after CRC diagnosis from all causes and 414 deaths directly attributed to CRC. CRC-specific survival was compared among women with diabetes with metformin use (n = 84); women with diabetes with no metformin use (n = 128); and women without diabetes (n = 1854). Cox proportional hazard models were used to estimate associations among metformin use, diabetes and survival after CRC. Strategies to adjust for potential confounders included: multivariate adjustment with known predictors of colorectal cancer survival and construction of a propensity score for the likelihood of receiving metformin, with model stratification by propensity score quintile. Results: After adjusting for age and stage, CRC specific survival in women with diabetes with metformin use was not significantly different compared to that in women with diabetes with no metformin use (HR 0.75; 95% CI 0.40–1.38, p = 0.67) and to women without diabetes (HR 1.00; 95% CI 0.61–1.66, p = 0.99). Following propensity score adjustment, the HR for CRC-specific survival in women with diabetes with metformin use compared to non-users was 0.78 (95% CI 0.38–1.55, p = 0.47) and for overall survival was 0.86 (95% CI 0.49–1.52; p = 0.60). Conclusions: In postmenopausal women with CRC and DM, no statistically significant difference was seen in CRC specific survival in those who used metformin compared to non-users. Analyses in larger populations of colorectal cancer patients are warranted. 相似文献
1000.
Maria Leticia Zarantonelli Anna Skoczynska Aude Antignac Meriem El Ghachi Ala-Eddine Deghmane Marek Szatanik Céline Mulet Catherine Werts Lucie Peduto Martine Fanton d’Andon Françoise Thouron Faridabano Nato Lionel LeBourhis Dana J. Philpott Stephen E. Girardin Francina Langa Vives Philippe Sansonetti Gérard Eberl Ivo G. Boneca 《Cell host & microbe》2013,13(6):735-745