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21.
Rohan S. Virgincar Zackary I. Cleveland S. Sivaram Kaushik Matthew S. Freeman John Nouls Gary P. Cofer Santiago Martinez‐Jimenez Mu He Monica Kraft Jan Wolber H. Page McAdams Bastiaan Driehuys 《NMR in biomedicine》2013,26(4):424-435
In this study, hyperpolarized 129Xe MR ventilation and 1H anatomical images were obtained from three subject groups: young healthy volunteers (HVs), subjects with chronic obstructive pulmonary disease (COPD) and age‐matched controls (AMCs). Ventilation images were quantified by two methods: an expert reader‐based ventilation defect score percentage (VDS%) and a semi‐automated segmentation‐based ventilation defect percentage (VDP). Reader‐based values were assigned by two experienced radiologists and resolved by consensus. In the semi‐automated analysis, 1H anatomical images and 129Xe ventilation images were both segmented following registration to obtain the thoracic cavity volume and ventilated volume, respectively, which were then expressed as a ratio to obtain the VDP. Ventilation images were also characterized by generating signal intensity histograms from voxels within the thoracic cavity volume, and heterogeneity was analyzed using the coefficient of variation (CV). The reader‐based VDS% correlated strongly with the semi‐automatically generated VDP (r = 0.97, p < 0.0001) and with CV (r = 0.82, p < 0.0001). Both 129Xe ventilation defect scoring metrics readily separated the three groups from one another and correlated significantly with the forced expiratory volume in 1 s (FEV1) (VDS%: r = –0.78, p = 0.0002; VDP: r = –0.79, p = 0.0003; CV: r = –0.66, p = 0.0059) and other pulmonary function tests. In the healthy subject groups (HVs and AMCs), the prevalence of ventilation defects also increased with age (VDS%: r = 0.61, p = 0.0002; VDP: r = 0.63, p = 0.0002). Moreover, ventilation histograms and their associated CVs distinguished between subjects with COPD with similar ventilation defect scores, but visibly different ventilation patterns. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Joyce G. Rohan Shawn M. McInturf Molly K. Miklasevich Chester P. Gut Michael D. Grimm James E. Reboulet 《Journal of toxicology and environmental health. Part A》2018,81(10):314-332
Exposure to fuels continues to be a concern in both military and general populations. The aim of this study was to examine effects of in vivo rat repeated exposures to different types of jet fuel utilizing microelectrode arrays for comparative electrophysiological (EP) measurements in hippocampal slices. Animals were exposed to increasing concentrations of four jet fuels, Jet Propellant (JP)-8, Jet A, JP-5, or synthetic Fischer Tropsch (FT) fuel via whole-body inhalation for 20 d (6 hr/d, 5 d/week for 28 d) and synaptic transmission as well as behavioral performance were assessed. Our behavioral studies indicated no significant changes in behavioral performance in animals exposed to JP-8, Jet A, or JP-5. A significant deviation in learning pattern during the Morris water maze task was observed in rats exposed to the highest concentration of FT (2000 mg/m3). There were also significant differences in the EP profile of hippocampal neurons from animals exposed to JP-8, Jet A, JP-5, or FT compared to control air. However, these differences were not consistent across fuels or dose dependent. As expected, patterns of EP alterations in brain slices from JP-8 and Jet A exposures were more similar compared to those from JP-5 and FT. Further longitudinal investigations are needed to determine if these EP effects are transient or persistent. Such studies may dictate if and how one may use EP measurements to indicate potential susceptibility to neurological impairments, particularly those that result from inhalation exposure to chemicals or mixtures. 相似文献
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The potential role of lung microbiota in lung cancer attributed to household coal burning exposures 下载免费PDF全文
Nathaniel Rothman Thomas Rohan Wei Hu Jun Xu Roel Vermeulen Xingzhou He James Robert White Guoping Wu Fusheng Wei Qing Lan 《Environmental and molecular mutagenesis》2014,55(8):643-651
Bacteria influence site‐specific disease etiology and the host's ability to metabolize xenobiotics, such as polycyclic aromatic hydrocarbons (PAHs). Lung cancer in Xuanwei, China has been attributed to PAH‐rich household air pollution from burning coal. This study seeks to explore the role of lung microbiota in lung cancer among never smoking Xuanwei women and how coal burning may influence these associations. DNA from sputum and buccal samples of never smoking lung cancer cases (n = 8, in duplicate) and controls (n = 8, in duplicate) in two Xuanwei villages was extracted using a multi‐step enzymatic and physical lysis, followed by a standardized clean‐up. V1‐V2 regions of 16S rRNA genes were PCR‐amplified. Purified amplicons were sequenced by 454 FLX Titanium pyrosequencing and high‐quality sequences were evaluated for diversity and taxonomic membership. Bacterial diversity among cases and controls was similar in buccal samples (P = 0.46), but significantly different in sputum samples (P = 0.038). In sputum, Granulicatella (6.1 vs. 2.0%; P = 0.0016), Abiotrophia (1.5 vs. 0.085%; P = 0.0036), and Streptococcus (40.1 vs. 19.8%; P = 0.0142) were enriched in cases compared with controls. Sputum samples had on average 488.25 species‐level OTUs in the flora of cases who used smoky coal (PAH‐rich) compared with 352.5 OTUs among cases who used smokeless coal (PAH‐poor; P = 0.047). These differences were explained by the Bacilli species (Streptococcus infantis and Streptococcus anginosus). Our small study suggests that never smoking lung cancer cases have differing sputum microbiota than controls. Further, bacteria found in sputum may be influenced by environmental exposures associated with the type of coal burned in the home. Environ. Mol. Mutagen. 55:643–651, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
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Aim: To investigate the prevalence of medication‐related problems (MRPs) in patients attending aged care and memory disorder clinics and explore the potential role of a clinical pharmacist to obtain medication histories and identify unresolved MRPs. Methods: The clinical pharmacist interviewed patients and reviewed their medication regimens in the outpatient clinics. Clinical significance of pharmacist‐identified MRPs was rated by an independent expert panel using validated criteria. Results: Forty‐six patients (mean age 82 years) were reviewed. They took a median of nine medications, of which three were not recorded in the medical record. One hundred and thirteen MRPs (median 2.0 per patient) were identified by the pharmacist. Independent review rated 35% of MRPs as high or extreme risk. Thirty‐seven (33%) MRPs related to medications not recorded in the medical record. Conclusions: Medication‐related problems were present for most patients. Involvement of a clinical pharmacist resulted in a more comprehensive medication history and identified unresolved MRPs. 相似文献
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D Rohan Jeyarajah Amit Khithani Veeraiah Siripurapu Elizabeth Liu Ashley Thomas A Joe Saad 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2014,16(3):263-266
Background:Many previous studies have suggested that the number of lymph nodes retrieved should serve as a benchmark for assessing the adequacy of the resection. The aim was to retrospectively observe the impact of nodal retrieval after educating the pathologist.Methods:Patients undergoing a pancreaticoduodenectomy (PD) between September 2005 and March 2009 were included in the study. The PDs performed between September 2005 and March 2008 were designated as Group A. The pathologistswere educated regarding the importance of nodal counts in PD by the surgeon on the 1st April 2008. PDs performed betweenApril 2008 and March 2009 were designated as Group B.Results:Ninety-eight PDs performed by a single surgeon (D.R.J.) for peri-ampullary malignancy were evaluated. The median number of lymph nodes retrieved in Group A was 11(3–32) nodes. The median number of lymph nodes retrieved in Group B was 22 (10–29) nodes (P < 0.001).The lymph node ratio (positive/total nodes), median number of positive nodes retrieved, and the node positivity (node positive compared to node negative) rate did not change.Discussion:A single intervention with the pathologists did impact the number of lymph nodes retrieved from PD specimens. However, the lymph node ratio and lymph node positivity rate remained unchanged. The pathologist is critical to nodal retrieval in PD, but the use of this lymph node number for benchmark of surgical adequacy may be simplistic. 相似文献
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