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51.
Saha Soma Pal Dey Poushali Mitra Souvik 《Proceedings of the National Academy of Sciences, India. Section B.》2021,91(4):919-927
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Microbial association is considered as a significant innovation for land colonization of mosses. Plagiomnium... 相似文献
52.
Mohammed N. Meah Trisha Singh Michelle C. Williams Marc R. Dweck David E. Newby Piotr Slomka Philip D. Adamson Alastair J. Moss Damini Dey 《Journal of Cardiovascular Computed Tomography》2021,15(4):333-338
BackgroundThe ability to characterize and to quantify the extent of coronary artery disease has the potential to improve the prognostic capability of coronary computed tomography angiography. Although reproducible techniques have been described in those with mild coronary disease, this has yet to be assessed in patients with advanced disease.MethodsTwenty patients with known multivessel disease underwent repeated computed tomography coronary angiography, 2 weeks apart. Coronary artery segments were analysed using semi-automated software by two trained observers to determine intraobserver, interobserver and interscan reproducibility.ResultsOverall, 149 coronary arterial segments were analysed. There was excellent intraobserver and interobserver agreement for all plaque volume measurements (Lin’s coefficient 0.95 to 1.0). There were no substantial interscan differences (P ?> ?0.05 for all) for total (2063 ?± ?1246 ?mm3, mean of differences ?35.6 ?mm3), non-calcified (1795 ?± ?910 ?mm3, mean of differences ?4.3 ?mm3), calcified (298 ?± ?425 ?mm3, mean of differences ?31.3 ?mm3) and low-attenuation (13 ?± ?13 ?mm3, mean of differences ?2.6 ?mm3) plaque volumes. Interscan agreement was highest for total and noncalcified plaque volumes. Calcified and low-attenuation plaque (?236.6 to 174 ?mm3 and -15.8 to 10.5 ?mm3 respectively) had relatively wider 95% limits of agreement reflecting the lower absolute plaque volumes.ConclusionIn the presence of advanced coronary disease, semi-automated plaque quantification provides excellent reproducibility, particularly for total and non-calcified plaque volumes. This approach has major potential to assess change in disease over time and optimize risk stratification in patients with established coronary artery disease. 相似文献
53.
Todd C. Villines Subhi J. Al’Aref Daniele Andreini Marcus Y. Chen Andrew D. Choi Carlo N. De Cecco Damini Dey James P. Earls Maros Ferencik Heidi Gransar Harvey Hecht Jonathon A. Leipsic Michael T. Lu Mohamed Marwan Pál Maurovich-Horvat Edward Nicol Gianluca Pontone Jonathan Weir-McCall Gudrun M. Feuchtner 《Journal of Cardiovascular Computed Tomography》2021,15(2):180-189
54.
The field of pain medicine that once began as a supportive and compassionate care, adding value to the management of acute and chronic ailments, has now transformed into a vital and essential specialty with structured training programs and service units with professionals dedicating their careers to it. The expansion of understanding of the direct relationship of pain relief to the quality of life, uncovering of neuronal pathways, and technological advances in imaging as well as in interventional techniques have all contributed to this phenomenal growth. However, there is a growing concern whether the training programs and the specialized practitioners are gradually limiting their skilled inputs primarily within the sensory realm of the pain experience with sophisticated interventional techniques and relegating its subjective and emotional dimensions to perfunctory realms within the schema of service provision. While the specialty is still young, if we can understand the inherent aspect of these dimensions within the pain experience and acknowledge the gaps in service provision, it may be possible to champion development of truly comprehensive pain relief programs that responds effectively and ethically to a patient''s felt needs. This article attempts to position the subjectivity of pain experience in context and surface the need to design complete systems of pain relief services inclusive of this dimension. It presents authors’ review of literature on perspectives of ‘unpleasant subjective emotional experiencing of the pain” to elucidate possible clinical implications based on the evidences presented on neuro-biology and neuro-psychology of the pain experience; the aim being to inspire systems of care where this dimension is sufficiently evaluated and managed. 相似文献
55.
Ranjith Tellis Olga Starobinets Michael Prokle Usha Nandini Raghavan Christopher Hall Tammana Chugh Ekin Koker Siva Chaitanya Chaduvula Christoph Wald Sebastian Flacke 《Journal of digital imaging》2021,34(1):75
Identifying areas for workflow improvement and growth is essential for an interventional radiology (IR) department to stay competitive. Deployment of traditional methods such as Lean and Six Sigma helped in reducing the waste in workflows at a strategic level. However, achieving efficient workflow needs both strategic and tactical approaches. Uncertainties about patient arrivals, staff availability, and variability in procedure durations pose hindrances to efficient workflow and lead to delayed patient care and staff overtime. We present an alternative approach to address both tactical and strategic needs using discrete event simulation (DES) and simulation based optimization methods. A comprehensive digital model of the patient workflow in a hospital-based IR department was modeled based on expert interviews with the incumbent personnel and analysis of 192 days’ worth of electronic medical record (EMR) data. Patient arrival patterns and process times were derived from 4393 individual patient appointments. Exactly 196 unique procedures were modeled, each with its own process time distribution and rule-based procedure-room mapping. Dynamic staff schedules for interventional radiologists, technologists, and nurses were incorporated in the model. Stochastic model simulation runs revealed the resource “computed tomography (CT) suite” as the major workflow bottleneck during the morning hours. This insight compelled the radiology department leadership to re-assign time blocks on a diagnostic CT scanner to the IR group. Moreover, this approach helped identify opportunities for additional appointments at times of lower diagnostic scanner utilization. Demand for interventional service from Outpatients during late hours of the day required the facility to extend hours of operations. Simulation-based optimization methods were used to model a new staff schedule, stretching the existing pool of resources to support the additional 2.5 h of daily operation. In conclusion, this study illustrates that the combination of workflow modeling, stochastic simulations, and optimization techniques is a viable and effective approach for identifying workflow inefficiencies and discovering and validating improvement options through what-if scenario testing. 相似文献
56.
Chhaya V Verma Rachna D Arora Hetal M Mistry Swati V Kubal Nandini S Kolwankar Pranali C Patil Anushka A Dalvi Sonal A Vichare Akhila Natesan Anagha N Mangaonkar Dolly D Kanakia Gayatri S Jere Karan Y Bansode Madhura R Patil Rajvi D Sheth Sandhya D Dudhavade Sayali D Mhatre Suresh K Patel Akanksha G Mohite Ankita N Bhavsar Jessica E Alfonso Maryam NA Syed Nidhi P Savla Riya N Rajgond Rutuja A Bute Samiksha M Mane Shubham R Jaiswal Vibhawari A Parab Abhiram M Kasbe Mohan A Joshi Ramesh N Bharmal 《Indian Journal of Critical Care Medicine》2021,25(3):317
57.
Nandini Suresh Haritha Jamuna Subbarao Velmurugan Natanasabapathy Anil Kishen 《Journal of endodontics》2021,47(7):1182-1190
IntroductionPhotoactivated chitosan-based nanoparticles can eliminate bacterial biofilm, inactivate endotoxins, improve resistance to biological degradation (resorption), and promote bone regeneration. This case is the first documentation to highlight the successful healing of teeth with extensive inflammatory root resorption (IRR) with periapical lesions using a combined surgical and nonsurgical root canal therapy using rose bengal functionalized chitosan nanoparticles (CSRBnp).MethodsA 17-year-old boy with extensive IRR of maxillary right canine (teeth #6), maxillary right lateral incisor (#7), maxillary right central incisor (#8), and maxillary left central incisor (#9) was treated with photoactivated CSRBnp, both intracanal as well as topically on resorptive defects and periapical lesions. The larger external resorptive defects on the root surfaces were restored with Biodentine, whereas the through-and-through periapical lesions were packed with sticky bone for Guided Bone Regeneration.ResultsAt 26 months of follow-up, the clinical, 2-dimensional (intraoral periapical radiographs) and 3-dimensional (cone-beam computed tomography) images showed absence of clinical symptoms, teeth mobility, arrested IRR, and significant osseous healing of the periradicular region. Postoperatively, the patient retraumatized thrice in relation to #7 resulting in horizontal root fracture, which showed type I pattern of root fracture healing in the follow-up.ConclusionsPhotoactivated chitosan-based nanoparticles can be a viable therapeutic option to hinder root resorption while enhancing healing outcomes in cases of severe IRR. 相似文献
58.
Yadhav A. Imrit Hanusha Bhakhoa Tetiana Sergeieva Sergi Dans Nandini Savoo Mohamed I. Elzagheid Lydia Rhyman Diego M. Andrada Ponnadurai Ramasami 《RSC advances》2020,10(47):27884
A-234, [EtO–P( O)(F)–N C(Me)–N(Et)2], is the suspected A-type nerve agent used in the Skripal attack on the 4th of March 2018. Studies related to the structure and reactivity of this compound are limited. We, therefore, aimed at understanding the underlying hydrolysis mechanism of A-234 within the DFT framework. The attack of the water molecule can occur at the phosphinate and acetoamidine reactive centres. Our theoretical findings indicate that the hydrolysis at the acetoamidine centre is thermodynamically favoured compared to the hydrolysis at the phosphinate centre. The hydrolysis at the acetoamidine moiety may proceed via two pathways, depending on the nitrogen atom participating in the hydrolysis. The main pathway consists of four distinct channels to reach the final product, with the concerted 1,3-proton shift favoured kinetically and thermodynamically in the gas phase and water as solvent. The results are in good agreement with the literature, although some differences in the reaction mechanism were observed.A theoretical study of the hydrolysis mechanism of A-234 [EtO–P( O)(F)–N C(Me)–N(Et)2]; the suspected novichok agent in the Skripal attack. 相似文献
59.
Correction for ‘Thermodynamically stable vesicle formation of biodegradable double mPEG-tailed amphiphiles with sulfonate head group’ by Rita Ghosh et al., RSC Adv., 2020, 10, 32522–32531, DOI: 10.1039/D0RA05613HThe authors regret that an incorrect version of Fig. 5 was included in the original article. The correct version of Fig. 5 is presented below.Open in a separate windowFig. 1Upper panel: Size distribution histograms of aggregates in 2.0 mM solutions (pH 7) of (a) (mPEG4)2SO3Na, and (b) (mPEG23)2SO3Na at 25 °C; lower panel: unstained HRTEM images of 2 mM (c) (mPEG4)2SO3Na and (d) (mPEG23)2SO3Na solutions in phosphate buffer (pH 7.0).The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers. 相似文献
60.
Saibal Dey Muralidhara Ramachandra Ira Pastan Michael M. Gottesman Suresh V. Ambudkar 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(20):10594-10599
Human P-glycoprotein (Pgp) confers multidrug resistance to cancer cells by ATP-dependent extrusion of a great many structurally dissimilar hydrophobic compounds. The manner in which Pgp recognizes these different substrates is unknown. The protein shows internal homology between its N- and C-terminal halves, each comprised of six putative transmembrane helices and a consensus ATP binding/utilization site. Photoactive derivatives of certain Pgp substrates specifically label two regions, one on each half of the protein. In this study, using [125I]iodoarylazidoprazosin ([125I]IAAP), a photoactive analog of prazosin, we have demonstrated the presence of two nonidentical drug-interaction sites within Pgp. Taking advantage of a highly susceptible trypsin cleavage site in the linker region of Pgp, we characterized the [125I]IAAP binding to the N- and C-terminal halves. cis(Z)-Flupentixol, a modulator of Pgp function, preferentially increased the affinity of [125I]IAAP for the C-terminal half of the protein (C-site) by reducing the Kd from 20 to 6 nM without changing the labeling or affinity (Kd = 42–46 nM) of the N-terminal half (N-site). Also, the concentration of vinblastine (Pgp substrate) and cyclosporin A (Pgp modulator) required for 50% inhibition of [125I]IAAP binding to the C-site was increased 5- to 6-fold by cis(Z)-flupentixol without any effect on the N-site. In addition, [125I]IAAP binding to the N-site was less susceptible than to C-site to inhibition by vanadate which blocks ATP hydrolysis and drug transport. These data demonstrate the presence of at least two nonidentical substrate interaction sites in Pgp. 相似文献