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991.
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Michael P. Thomas Craig S. Parzynski Jeptha P. Curtis Milan Seth Brahmajee K. Nallamothu Paul S. Chan John A. Spertus Manesh R. Patel Steven M. Bradley Hitinder S. Gurm 《PloS one》2015,10(9)
Background
Substantial geographic variation exists in percutaneous coronary intervention (PCI) use across the United States. It is unclear the extent to which high PCI utilization can be explained by PCI for inappropriate indications. The objective of this study was to examine the relationship between PCI rates across regional healthcare markets utilizing hospital referral regions (HRRs) and PCI appropriateness.Methods
The number of PCI procedures in each HRR was obtained from the 2010 100% Medicare limited data set. HRRs were divided into quintiles of PCI utilization with increasing rates of utilization progressing to quintile 5. NCDR CathPCI Registry® data were used to evaluate patient characteristics, appropriate use criteria (AUC), and outcomes across the HRR quintiles defined by PCI utilization with the study population restricted to HRRs where ≥ 80% of the PCIs were performed at institutions participating in the registry. PCI appropriateness was defined using 2012 AUC by the American College of Cardiology (ACC)/American Heart Association (AHA)/The Society for Cardiovascular Angiography and Interventions (SCAI).Results
Our study cohort comprised of 380,981 patients treated at 178 HRRs. Mean PCI rates per 1,000 increased from 4.6 in Quintile 1 to 10.8 in Quintile 5. The proportion of non-acute PCIs was 27.7% in Quintile 1 increasing to 30.7% in Quintile 5. Significant variation (p < 0.001) existed across the quintiles in the categorization of appropriateness across HRRs of utilization with more appropriate PCI in lower utilization areas (Appropriate: Q1, 76.53%, Q2, 75.326%, Q3, 75.23%, Q4, 73.95%, Q5, 72.768%; Inappropriate: Q1 3.92%, Q2 4.23%, Q3 4.32%, Q4 4.35%, Q5 4.05%; Uncertain: Q1 8.29%, Q2 8.84%, Q3 8.08%, Q4 9.01%, Q5 8.93%; Not Mappable: Q1 11.26%, Q2 11.67%, Q3 12.37%, Q4 12.69%, Q5 14.34%). There was no difference in risk-adjusted mortality across quintiles of PCI utilization.Conclusions
Geographic regions with lower PCI rates have a higher proportion of PCIs performed for appropriate indications. Areas that perform more PCIs also appear to perform more elective PCI and many could not be mapped by the AUC. 相似文献994.
Mark W. Eshoo Heather E. Carolan Christian Massire Danny M. Chou Chris D. Crowder Megan A. Rounds Curtis A. Phillipson Steven E. Schutzer David J. Ecker 《PloS one》2015,10(9)
Ixodes pacificus ticks can harbor a wide range of human and animal pathogens. To survey the prevalence of tick-borne known and putative pathogens, we tested 982 individual adult and nymphal I. pacificus ticks collected throughout California between 2007 and 2009 using a broad-range PCR and electrospray ionization mass spectrometry (PCR/ESI-MS) assay designed to detect a wide range of tick-borne microorganisms. Overall, 1.4% of the ticks were found to be infected with Borrelia burgdorferi, 2.0% were infected with Borrelia miyamotoi and 0.3% were infected with Anaplasma phagocytophilum. In addition, 3.0% were infected with Babesia odocoilei. About 1.2% of the ticks were co-infected with more than one pathogen or putative pathogen. In addition, we identified a novel Anaplasmataceae species that we characterized by sequencing of its 16S rRNA, groEL, gltA, and rpoB genes. Sequence analysis indicated that this organism is phylogenetically distinct from known Anaplasma species with its closest genetic near neighbors coming from Asia. The prevalence of this novel Anaplasmataceae species was as high as 21% at one site, and it was detected in 4.9% of ticks tested statewide. Based upon this genetic characterization we propose that this organism be called ‘Candidatus Cryptoplasma californiense’. Knowledge of this novel microbe will provide awareness for the community about the breadth of the I. pacificus microbiome, the concept that this bacterium could be more widely spread; and an opportunity to explore whether this bacterium also contributes to human or animal disease burden. 相似文献
995.
Geoffrey E. Lynn Jonathan D. Oliver Curtis M. Nelson Roderick F. Felsheim Timothy J. Kurtti Ulrike G. Munderloh 《PloS one》2015,10(3)
Human pathogens transmitted by ticks undergo complex life cycles alternating between the arthropod vector and a mammalian host. While the latter has been investigated to a greater extent, examination of the biological interactions between microbes and the ticks that carry them presents an equally important opportunity for disruption of the disease cycle. In this study, we used in situ hybridization to demonstrate infection by the Ehrlichia muris-like organism, a newly recognized human pathogen, of Ixodes scapularis ticks, a primary vector for several important human disease agents. This allowed us to assess whole sectioned ticks for the patterns of tissue invasion, and demonstrate generalized dissemination of ehrlichiae in a variety of cell types and organs within ticks infected naturally via blood feeding. Electron microscopy was used to confirm these results. Here we describe a strong ehrlichial affinity for epithelial cells, neuronal cells of the synganglion, salivary glands, and male accessory glands. 相似文献
996.
Claudia Agnoli Sara Grioni Sabina Sieri Carlotta Sacerdote Fulvio Ricceri Rosario Tumino Graziella Frasca Valeria Pala Amalia Mattiello Paolo Chiodini Licia Iacoviello Amalia De Curtis Salvatore Panico Vittorio Krogh 《PloS one》2015,10(6)
Background
Metabolic syndrome (defined as at least three among abdominal obesity, high blood triglycerides, low high-density lipoprotein cholesterol, high blood glucose, and high blood pressure) is emerging as a risk factor for breast cancer; however few studies – most confined to postmenopausal women – have investigated associations between breast cancer risk and metabolic syndrome. The purpose of this study was to examine the association between metabolic syndrome and its components, and risk of breast cancer in postmenopausal and premenopausal women.Methods
We performed a case-cohort study on 22,494 women recruited in 1993-1998 to four Italian centres (Turin, Varese, Naples, Ragusa) of the European Prospective Investigation into Cancer and Nutrition (EPIC) and followed-up for up to 15 years. A random subcohort of 565 women was obtained and 593 breast cancer cases were diagnosed. Hazard ratios (HR) with 95% confidence intervals (CI), adjusted for potential confounders, were estimated by Prentice-weighted Cox proportional hazards models.Results
Presence of metabolic syndrome was associated with significantly increased breast cancer risk in all women (HR 1.52, 95%CI 1.14-2.02). When the analyses were repeated separately for menopausal status, the association was limited to postmenopausal women (HR 1.80, 95%CI 1.22-2.65) and absent in premenopausal women (HR 0.71, 95%CI 0.43-1.16); P for interaction between metabolic syndrome and menopausal status was 0.001. Of metabolic syndrome components, only high blood glucose was significantly associated with increased breast cancer risk in all women (HR 1.47, 95%CI 1.13-1.91) and postmenopausal women (HR 1.89, 95%CI 1.29-2.77), but not premenopausal women (HR 0.80, 95%CI 0.52-1.22; P interaction=0.004).Conclusions
These findings support previous data indicating that metabolic syndrome is an important risk factor for breast cancer in postmenopausal women, but not in premenopausal women, and suggest that prevention of metabolic syndrome through lifestyle changes could confer protection against breast cancer. 相似文献997.
998.
A high‐density,SNP‐based consensus map of tetraploid wheat as a bridge to integrate durum and bread wheat genomics and breeding 下载免费PDF全文
Marco Maccaferri Andrea Ricci Silvio Salvi Sara Giulia Milner Enrico Noli Pier Luigi Martelli Rita Casadio Eduard Akhunov Simone Scalabrin Vera Vendramin Karim Ammar Antonio Blanco Francesca Desiderio Assaf Distelfeld Jorge Dubcovsky Tzion Fahima Justin Faris Abraham Korol Andrea Massi Anna Maria Mastrangelo Michele Morgante Curtis Pozniak Amidou N'Diaye Steven Xu Roberto Tuberosa 《Plant biotechnology journal》2015,13(5):648-663
999.
1000.
Native mass spectrometry and ion mobility characterization of trastuzumab emtansine,a lysine-linked antibody drug conjugate 下载免费PDF全文
Julien Marcoux Thierry Champion Olivier Colas Elsa Wagner-Rousset Nathalie Corva?a Alain Van Dorsselaer Alain Beck Sarah Cianférani 《Protein science : a publication of the Protein Society》2015,24(8):1210-1223
Antibody–drug conjugates (ADCs) are biochemotherapeutics consisting of a cytotoxic chemical drug linked covalently to a monoclonal antibody. Two main classes of ADCs, namely cysteine and lysine conjugates, are currently available on the market or involved in clinical trials. The complex structure and heterogeneity of ADCs makes their biophysical characterization challenging. For cysteine conjugates, hydrophobic interaction chromatography is the gold standard technique for studying drug distribution, the naked antibody content, and the average drug to antibody ratio (DAR). For lysine ADC conjugates on the other hand, which are not amenable to hydrophobic interaction chromatography because of their higher heterogeneity, denaturing mass spectrometry (MS) and UV/Vis spectroscopy are the most powerful approaches. We report here the use of native MS and ion mobility (IM-MS) for the characterization of trastuzumab emtansine (T-DM1, Kadcyla®). This lysine conjugate is currently being considered for the treatment of human epidermal growth factor receptor 2 (HER2)-positive breast cancer, and combines the anti-HER2 antibody trastuzumab (Herceptin®), with the cytotoxic microtubule-inhibiting maytansine derivative, DM1. We show that native MS combined with high-resolution measurements and/or charge reduction is beneficial in terms of the accurate values it provides of the average DAR and the drug load profiles. The use of spectral deconvolution is discussed in detail. We report furthermore the use of native IM-MS to directly determine DAR distribution profiles and average DAR values, as well as a molecular modeling investigation of positional isomers in T-DM1. 相似文献