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31.
32.
Masliza Mahmod Nikhil Pal Jennifer Rayner Cameron Holloway Betty Raman Sairia Dass Eylem Levelt Rina Ariga Vanessa Ferreira Rajarshi Banerjee Jurgen E. Schneider Christopher Rodgers Jane M. Francis Theodoros D. Karamitsos Michael Frenneaux Houman Ashrafian Stefan Neubauer Oliver Rider 《Journal of cardiovascular magnetic resonance》2018,20(1):88
Background
Heart failure (HF) is characterized by altered myocardial substrate metabolism which can lead to myocardial triglyceride accumulation (steatosis) and lipotoxicity. However its role in mild HF with preserved ejection fraction (HFpEF) is uncertain. We measured myocardial triglyceride content (MTG) in HFpEF and assessed its relationships with diastolic function and exercise capacity.Methods
Twenty seven HFpEF (clinical features of HF, left ventricular EF >50%, evidence of mild diastolic dysfunction and evidence of exercise limitation as assessed by cardiopulmonary exercise test) and 14 controls underwent 1H-cardiovascular magnetic resonance spectroscopy (1H-CMRS) to measure MTG (lipid/water, %), 31P-CMRS to measure myocardial energetics (phosphocreatine-to-adenosine triphosphate - PCr/ATP) and feature-tracking cardiovascular magnetic resonance (CMR) imaging for diastolic strain rate.Results
When compared to controls, HFpEF had 2.3 fold higher in MTG (1.45?±?0.25% vs. 0.64?±?0.16%, p?=?0.009) and reduced PCr/ATP (1.60?±?0.09 vs. 2.00?±?0.10, p?=?0.005). HFpEF had significantly reduced diastolic strain rate and maximal oxygen consumption (VO2 max), which both correlated significantly with elevated MTG and reduced PCr/ATP. On multivariate analyses, MTG was independently associated with diastolic strain rate while diastolic strain rate was independently associated with VO2 max.Conclusions
Myocardial steatosis is pronounced in mild HFpEF, and is independently associated with impaired diastolic strain rate which is itself related to exercise capacity. Steatosis may adversely affect exercise capacity by indirect effect occurring via impairment in diastolic function. As such, myocardial triglyceride may become a potential therapeutic target to treat the increasing number of patients with HFpEF.33.
Prompt serum copper and zinc in addition to vitamin B12 levels should be measured in patients suffering from refractory anemia with neurological symptoms. A timely copper supplementation can help revert the hematological and possibly the neurological manifestations. 相似文献
34.
Kumaragurubaran?KarthikEmail authorView authors OrcID profile Ramalingam?Mahaprabhu Parimal?Roy Muthusamy?Raman 《Proceedings of the National Academy of Sciences, India. Section B.》2018,88(4):1409-1412
An investigation was carried out in an organized dairy farm of Tamil Nadu State, India where cattle were reported to have eye infection. Preliminary clinical intervention revealed that the animals had infectious bovine keratoconjunctivitis (IBK). Isolation and identification of pathogen from eye swab revealed the presence of Moraxella spp. On further molecular characterization by Polymerase chain reaction (PCR) suggested that the isolate as Moraxella bovoculi. PCR followed by sequencing was carried and the results showed that the isolate was M. bovoculi and the sequence was submitted in the GenBank with the sequence id. KX121047. Animals were treated with antibiotics as per the results from antibiotic sensitivity test and treatment yielded good results as the animals responded to treatment. This report is the first of its kind from India as there was no previous report regarding M. bovoculi from the country. Further insights into the bacterial genome can aid in identification of the genes or regions involved in pathogenesis of IBK and also to carve out the prevention and control strategies of IBK. 相似文献
35.
Asvadi Nazanin Hajarol Afshari Mirak Sohrab Mohammadian Bajgiran Amirhossein Khoshnoodi Pooria Wibulpolprasert Pornphan Margolis Daniel Sisk Anthony Reiter Robert E. Raman Steven S. 《Abdominal imaging》2018,43(11):3117-3124
Abdominal Radiology - To evaluate 3T mpMRI characteristics of transition zone and peripheral zone index prostate cancer lesions stratified by Gleason Score and PI-RADSv2 with whole mount... 相似文献
36.
Purpose
To provide normal macular thickness measurements using Spectral Domain Optical Coherence Tomography (SDOCT, Copernicus, Optopol Technologies, Zawierci, Poland).Methods
Fifty-eight eyes of 58 healthy subjects were included in this prospective study. All subjects had comprehensive ophthalmic examination including best-corrected visual acuity (BCVA). All the subjects underwent Copernicus SDOCT. Central foveal thickness (CFT) and photoreceptor layer (PRL) thickness were measured and expressed as mean and standard deviation. Mean retinal thickness for each of the 9 regions defined in the Early Treatment Diabetic Retinopathy Study was reported. The data were compared with published literature in Indians using Stratus and Spectralis OCTs to assess variation in instrument measurements.Results
The mean CFT in the study sample was 173.8 ± 18.16 microns (131–215 microns) and the mean PRL thickness was 65.48 ± 4.23 microns (56–74 microns). No significant difference (p = 0.148) was found between CFT measured automated (179.28 ± 22 microns) and manually (173.83 ± 18.1 microns). CFT was significantly lower in women (167.62 ± 16.36 microns) compared to men (180.03 ± 18 microns) (p = 0.008). Mean retinal thickness reported in this study was significantly different from published literature using Stratus OCT and Spectralis OCT.Conclusion
We report the normal mean retinal thickness in central 1 mm area to be between 138 and 242 microns in Indian population using Copernicus SDOCT. We suggest that different OCT instruments cannot be used interchangeably for the measurement of macular thickness as they vary in segmentation algorithms. 相似文献37.
Parth Makker MD Moussa Saleh MD Aditi S. Vaishnav MBBS Kristie M. Coleman RN Stuart Beldner MD Haisam Ismail MD Nikhil Sharma MD Ram Jadonath MD Bruce Goldner MD Raman Mitra MD PhD Laurence Epstein MD Roy John MD Stavros E. Mountantonakis MD 《Journal of cardiovascular electrophysiology》2021,32(6):1658-1664
38.
Pain on common bile duct injection during ERCP: does it indicate sphincter of Oddi dysfunction? 总被引:1,自引:0,他引:1
M J Schmalz J E Geenen W J Hogan W J Dodds R P Venu G K Johnson 《Gastrointestinal endoscopy》1990,36(5):458-461
The reproduction of a patient's biliary-type pain upon initial injection of contrast material into the common bile duct during diagnostic ERCP is a dramatic experience for both patient and physician. The significance of this phenomenon is not clear, but it is touted by some to be a provocative test for sphincter of Oddi dysfunction. Sphincter of Oddi manometry was performed on 224 consecutive patients referred over a 2-year period for evaluation of post-cholecystectomy syndrome and suspected sphincter of Oddi dysfunction. All patients received only intravenous diazepam as premedication for ERCP. Delayed drainage time (greater than 45 min), bile duct dilation (greater than or equal to 12 mm), and a basal sphincter of Oddi pressure of greater than 40 mm Hg (mean +/- 3 SD) were considered elevated. We observed a reproduction of pain in 15 of 224 patients (6.7%) immediately following contrast injection. There was no correlation between pain on contrast injection and elevated basal sphincter of Oddi pressure, delayed common bile duct drainage, bile duct dilation, or abnormal liver enzymes. Therefore, we feel that reproduction of the patient's biliary-type pain associated with contrast injection of ERCP is not a provocative test for sphincter of Oddi dysfunction. 相似文献
39.
Sequencing of 3-O sulfate containing heparin decasaccharides with a partial antithrombin III binding site 下载免费PDF全文
Shriver Z Raman R Venkataraman G Drummond K Turnbull J Toida T Linhardt R Biemann K Sasisekharan R 《Proceedings of the National Academy of Sciences of the United States of America》2000,97(19):10359-10364
Heparin- and heparan sulfate-like glycosaminoglycans (HLGAGs) represent an important class of molecules that interact with and modulate the activity of growth factors, enzymes, and morphogens. Of the many biological functions for this class of molecules, one of its most important functions is its interaction with antithrombin III (AT-III). AT-III binding to a specific heparin pentasaccharide sequence, containing an unusual 3-O sulfate on a N-sulfated, 6-O sulfated glucosamine, increases 1,000-fold AT-III's ability to inhibit specific proteases in the coagulation cascade. In this manner, HLGAGs play an important biological and pharmacological role in the modulation of blood clotting. Recently, a sequencing methodology was developed to further structure-function relationships of this important class of molecules. This methodology combines a property-encoded nomenclature scheme to handle the large information content (properties) of HLGAGs, with matrix-assisted laser desorption ionization MS and enzymatic and chemical degradation as experimental constraints to rapidly sequence picomole quantities of HLGAG oligosaccharides. Using the above property-encoded nomenclature-matrix-assisted laser desorption ionization approach, we found that the sequence of the decasaccharide used in this study is DeltaU(2S)H(NS,6S)I(2S)H(NS, 6S)I(2S)H(NS,6S)IH(NAc,6S)GH(NS,3S,6S) (+/-DDD4-7). We confirmed our results by using integral glycan sequencing and one-dimensional proton NMR. Furthermore, we show that this approach is flexible and is able to derive sequence information on an oligosaccharide mixture. Thus, this methodology will make possible both the analysis of other unusual sequences in HLGAGs with important biological activity as well as provide the basis for the structural analysis of these pharamacologically important group of heparin/heparan sulfates. 相似文献
40.
Joachim G. Eichhorn MD Frederick R. Long MD Claudia Jourdan MD Johannes T. Heverhagen MD PhD Sharon L. Hill ARNP Subha V. Raman MD John P. Cheatham MD 《Catheterization and cardiovascular interventions》2008,72(4):544-551
Objective : To evaluate varying CT settings to visualize pediatric vascular stents in comparison to digital angiography (DA). Background : There is a great clinical interest in substituting noninvasive methods to follow up children with congenital heart disease after interventional treatment. Materials and Methods : CT studies in small children with transcatheter placed stents were reviewed, retrospectively. Furthermore, eight stents were implanted in tubes and partially obstructed. CT exams were performed on varying scanners (4 up to 64 slices) with corresponding tube settings. The effects of dose on image quality were evaluated regarding stent size, strut thickness, and in‐stent stenoses in comparison to DA. Results : Fourteen children with 28 implanted stents were identified. Significant differences between higher and lower radiation settings were not found, corresponding with the phantom, where moderate tube setting showed the best results. In vitro, there was an improvement with increasing number of detector rows, which resulted in a decrease of stent strut overestimation (295% down to 201%; P < 0.0001) and a better agreement with DA measurements for mild (78% up to 91%; P = 0.003) and moderate in‐stent stenoses (80% up to 99%; P = 0.0001). Conclusion : Higher radiation exposure settings did not improve image quality, suggesting that the exams could be performed at a lower radiation dose. © 2008 Wiley‐Liss, Inc. 相似文献