85 results on '"Dsouza R"'
Search Results
2. Future microbond testing - finite element simulation of optical fibers for strains
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International Conference on Composite Materials (22nd : 2019 : Melboune, VIC.), Dsouza, R, Jokinen, J, Sarlin, E, Antunes, P, and Kanerva, M
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- 2019
3. Development and validation of a computer crash simulation model of an occupied adult manual wheelchair subjected to a frontal impact
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Dsouza, R. and Bertocci, G.
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- 2010
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4. Human Coronaviruses In Severe Acute Respiratory Infection (SARI) Cases in Southwest India
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Suresha, Prabhu G., Akhil, Chameettachal, Anjali, Aithal, Giselle, Dsouza R., Revti, Bhaskar, and Arunkumar, Govindakarnavar
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- 2016
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5. Experimental and numerical dataset of Microbond test using optical fibres for strain
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Dsouza, R., Antunes, P., Kakkonen, M., Jokinen, J., Sarlin, E., Kallio, P., and Kanerva, M.
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Engineering ,Optical fibres ,Debonding ,Finite element analysis (FEA) ,lcsh:R858-859.7 ,Interface ,lcsh:Computer applications to medicine. Medical informatics ,lcsh:Science (General) ,Cohesive Zone Modelling ,lcsh:Q1-390 - Abstract
This data article provides useful information often required for numerical modeling of the so-called microbond tests. It includes the experimental and simulation data of the microbond testing using Fibre Bragg Grating (FBG) fibres for optical strains. Microbond testing was performed on five different droplets of varying embedded length and diameter to collect the data. Finite element simulation was carried out and modelling was validated, by using two variables force and strain, to collect the data. The output data of the fitted models is given and is also visualized via graphs of force-strain derivative curves. The data of the simulations is provided for different finite element mesh densities. Here, to clarify the type and form of the data for the use by readers, the energy distribution curves describing various functionalities of the droplet, fibre and interface are presented. For further reading, the interpretation and analysis of this data can be found in a research article titled "3D interfacial debonding during microbond testing: Advantages of local strain recording" (R. Dsouza et al., 2020) [1]. published
- Published
- 2020
6. Experimental and numerical dataset of Microbond test using optical fibres for strain
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Dsouza, R., Antunes, P., Kakkonen, M., Jokinen, J., Sarlin, E., Kallio, P., Kanerva, M., Tampere University, Materials Science and Environmental Engineering, Research group: Plastics and Elastomer Technology, BioMediTech, and Research group: Micro and Nanosystems Research Group
- Subjects
216 Materials engineering - Abstract
This data article provides useful information often required for numerical modeling of the so-called microbond tests. It includes the experimental and simulation data of the microbond testing using Fibre Bragg Grating (FBG) fibres for optical strains. Microbond testing was performed on five different droplets of varying embedded length and diameter to collect the data. Finite element simulation was carried out and modelling was validated, by using two variables force and strain, to collect the data. The output data of the fitted models is given and is also visualized via graphs of force-strain derivative curves. The data of the simulations is provided for different finite element mesh densities. Here, to clarify the type and form of the data for the use by readers, the energy distribution curves describing various functionalities of the droplet, fibre and interface are presented. For further reading, the interpretation and analysis of this data can be found in a research article titled “3D interfacial debonding during microbond testing: Advantages of local strain recording” (R. Dsouza et al., 2020) [1]. publishedVersion
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- 2020
7. 3D interfacial debonding during microbond testing: Advantages of local strain recording
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Dsouza, R., primary, Antunes, P., additional, Kakkonen, M., additional, Jokinen, J., additional, Sarlin, E., additional, Kallio, P., additional, and Kanerva, M., additional
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- 2020
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8. Enthüllung von Schlüsselmoden in Photoprozessen unter Verwendung von ab-initio Moleculardynamik
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Dsouza, R.
- Abstract
The Born-Oppenheimer (BO) approximation represents one of the milestones achieved in the development of molecular physics. The resulting concept of an adiabatic potential energy surface (PES) is fundamental to our understanding of photoprocesses and reaction dynamics. The dynamics of the nuclei on a single BO potential-energy surface is a good rationalization of dynamics occurring in chemical processes. In many situations, the motion of nuclei on the PES of a single adiabatic state provides a realistic description of molecular dynamics. However, under certain conditions, the BO approximation breaks down, and picture of a single PES is not valid any longer. This typically happens in the course of photoinduced reactions, charge transfer processes, and molecular collision and fragmentation processes. The time-evolution of the system must then be described in terms of a number of PESs which are nonadiabatically coupled to one another. Nonadiabatic processes usually involve nuclear dynamics on at least two coupled PESs and thus cannot be rationalized within the BO approximation. Radiationless relaxation in electronic excited states is mediated by either an internal conversion (IC) or an inter-system crossing (ISC) process. Conical Intersections (CI) are the central requirement to understand the radiationless relaxation process and have been an important tool to model IC and ISC in polyatomic systems. The understanding, as well as the optimization of CIs in molecular systems, requires computational tools that can describe the dynamical correlation and configurations interaction of the system in electronically excited states. An established tool for elucidating mechanisms of chemical reactions that occur in the electronic excited state is Ab Initio molecular dynamics (AIMD). However, to describe photo processes by AIMD, an underlying electronic-structure method that can treat excited states is necessary. Time-dependent density functional theory (TDDFT) provides a in principle exact description of electronically excited states. Compared to wavefunction-based methods, TDDFT is computationally less demanding and is relatively straightforward and easy to use. To model radiationless relaxation in systems, a state-to-state modelling procedure is required. This is facilitated by Mixed quantum-classical (MQC) scheme in particular, surface hopping (SH) method. In this thesis, a TDDFT based MQC method, that can account for non-adiabatic effects in photo processes is implemented. The non-adiabatic scheme is based on the fewest switches trajectory surface hopping (FSSH) method introduced by John Tully. The method is applied to describe chemical processes, such as isomerization and intravibrational relaxation, that occur upon photoexcitation of the photochromic systems like Spironapthopyran (SNP). In the case of SNP, the results of the TDDFT-MQC method are in good agreement with PES simulations based on the state-averaged complete active space (SA-CASSCF) method, both concerning the observed reaction mechanisms and the excited state lifetimes which are obtained from experiments conducted in-house. Parallel to this work, we applied second order algebraic diagrammatic construction (ADC(2)) for the possible refinement of the postulated reaction mechanism and energies in the case of N-methylmorpholine. The ADC(2)-based MQC simulations confirm the main experimental trends, energetics and provide an accurate description of the reaction mechanism. Additionally, a critical assessment is made for the accuracy of the ab-initio methods employed throughout this work and possible extension to modeling reactions in solid-state. Die Born-Oppenheimer Näherung (BOA) ist ein Meilenstein in der Entwicklung der Molekülphysik. Das daraus resultierende Konzept einer adiabatischen Potenzialfläche (PES) ist grundlegend für unser Verständnis von Photonenprozessen und Reaktionsdynamiken. Die Dynamik der Kerne auf einer einzelnen PES ist eine gute Erklärung für die Dynamik von chemischen Prozessen. In vielen möglichen Situationen liefert die Bewegung von Kernen auf der PES eines einzelnen adiabatischen Zustands eine realistische Beschreibung der Molekulardynamik. In einigen Fällen jedoch bricht die BOA jedoch zusammen und das Bild einer einzelnen PES ist nicht mehr anwendbar. Dies geschieht typischerweise im Verlauf von photoinduzierten Reaktionen, Ladungstransferprozessen sowie molekularen Kollisions- und Fragmentierungsprozessen. Unter diesen Bedingungen muss die zeitliche Entwicklung des Systems unter Betrachtung mehrerer PES beschrieben werden, die nichtadiabatisch miteinander gekoppelt sind. Nichtadiabatische Prozesse beinhalten normalerweise Kerndynamik auf mindestens zwei gekoppelten PES und können daher nicht innerhalb der BOA beschrieben werden. Typische Phänomene, die mit einer Verletzung der Born-Oppenheimer-Näherung einhergehen, sind die strahlungslose Relaxation angeregter elektronischer Zustände, Ladungstransferprozesse, photoinduzierter molekularer Zerfall und Isomerisierungsprozesse mehratomiger Moleküle. Die strahlungslose Relaxation in elektronisch angeregten Zustäden entweder über einen internen Umwandlungsprozess (IC) oder einen Inter-System-Crossing-Prozess (ISC) geschient. Konische Durchschneidungen (CI) sind die zentrale Voraussetzung für das Verständnis des strahlungslosen Relaxationsprozesses und ein wichtiges Instrument zur Modellierung von IC und ISC in mehratomigen Systemen. Das Verständnis sowie die Optimierung von CIs in molekularen Systemen erfordern Rechenwerkzeuge, die dynamische Korrelation und Konfigurationswechselwirkung des Systems in elektronisch angeregten Zuständen beschreiben können. Ein etabliertes Werkzeug zur Aufklärung der Mechanismen chemischer Reaktionen, die in elektronisch angeregten Zuständen ablaufen, ist die Ab Initio Moleküldynamik (AIMD). Zur Beschreibung von Photonenprozessen durch AIMD ist jedoch eine zugrunde liegende elektronische Strukturmethode erforderlich, mit der angeregte Zustände behandelt werden können. Die zeitabhängige Dichtefunktionaltheorie (TDDFT) liefert eine im Prinzip genaue Beschreibung elektronisch angeregter Zustände. Im Vergleich zu Wellenfunktions methoden ist TDDFT weniger rechenintensiv und benutzerfreundlich. Um die strahlungslose Relaxation in Systemen modellieren zu können, ist ein Zustands-Modellierungsverfahren erforderlich, welches durch das Mixed quantum-classical (MQC)-schema, insbesondere die Surface Hopping-Methode, gegeben ist. In dieser Arbeit wird eine TDDFT-basierte MQC-Methode implementiert, die nicht-adiabatische Effekte in Photoprozessen berücksichtigen kann. Das nicht-adiabatische Schema basiert auf der von John Tully eingeführten minimalen FSSH-Methode (Trajectory Surface Hopping). Die Methode wird angewendet, um chemische Prozesse wie Isomerisierung und IC zu beschreiben, die bei Photoanregung von photochromen Systemen wie Spironapthopyran (SNP) auftreten. Im Falle von SNP stimmen die Ergebnisse der TDDFT-MQC-Methode gut mit PESSimulationen überein, die auf der Methode des zustandsgemittelten vollständigen aktiven Raums (SA-CASSCF) basieren. Dies gilt sowohl hinsichtlich der beobachteten Reaktionsmechanismen als auch der angeregten Zustandslebensdauern, wie kürzlich selbst durchgeführte Experimente zeigen. Durch die Verwendung von MQC innerhalb von Second Order Algebraic Digrammatic Construction (ADC(2)) wird die Verfeinerung des postulierten Reaktionsmechanismus und der Energiezustände ermöglicht. Im Falle von N-methylmorpholin bestätigen die ADC(2)-Simulationen die generellen experimentellen Trends, die Energielevel sowie eine genaue Beschreibung des Reaktionsmechanismus. Zusätzlich wird eine kritische Bewertung der Genauigkeit der in dieser Arbeit verwendeten ab-initio-methoden und einer möglichen Ausweitung auf Modellierung von Reaktionen in Festkörpern vorgenommen.
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- 2019
9. Circulating Genotypes of Dengue-1 Virus in South West India, 2014-2015
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Kumar Rajendra, Sushama Aswathyraj, Govindakarnavar Arunkumar, Maity Hindol, Dsouza R. Giselle, Aithal Anjali, Bhaskar Revti, Ramachandran Sanjay, Shetty Pooja, and Sasidharanpillai Sabeena
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0301 basic medicine ,Microbiology (medical) ,Serotype ,Genotype ,viruses ,Ns1 antigen ,India ,Envelope Gene ,Dengue virus ,Biology ,medicine.disease_cause ,History, 21st Century ,Virus ,Dengue fever ,Dengue ,03 medical and health sciences ,Viral Envelope Proteins ,medicine ,Humans ,Phylogeny ,virus diseases ,General Medicine ,Sequence Analysis, DNA ,biochemical phenomena, metabolism, and nutrition ,Dengue Virus ,medicine.disease ,Virology ,030104 developmental biology ,Infectious Diseases ,RNA, Viral ,Mild fever - Abstract
Dengue is the most prevalent arboviral disease affecting humans, with tropical and subtropical regions having the highest risk of dengue virus infections. The clinical symptoms often range from mild fever to fever with hemorrhagic manifestations and shock. Since 2010, India has been witnessing a marked increase in the number of dengue virus serotype 1 (DENV-1) infections, apart from those of serotypes 2 (DENV-2) and 3 (DENV-3). The present study was undertaken to understand the circulating genotypes of DENV-1 in South West India, by sequencing the envelope gene of DENV-1 samples representative of the 2014-2015 time period. The extracted RNAs from dengue NS1 antigen ELISA-positive samples, archived at the APEX Referral Laboratory for Arboviruses (National Vector Borne Disease Control Programme, Manipal Centre for Virus Research), were used for the study. The currently circulating genotypes of DENV-1 identified from the study area belong to genotypes V and I. Multicentric laboratory-based studies analyzing the envelope gene of all dengue serotypes are required from endemic countries like India.
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- 2017
10. Human coronaviruses in severe acute respiratory infection (SARI) cases in southwest India
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Bhaskar Revti, Prabhu G. Suresha, Dsouza R. Giselle, Govindakarnavar Arunkumar, Aithal Anjali, and Chameettachal Akhil
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0301 basic medicine ,Respiratory tract infections ,business.industry ,Cross-sectional study ,viruses ,Coronaviridae Infections ,virus diseases ,Retrospective cohort study ,medicine.disease_cause ,Virology ,Virus ,03 medical and health sciences ,030104 developmental biology ,Infectious Diseases ,medicine.anatomical_structure ,Throat ,Etiology ,medicine ,business ,Coronavirus - Abstract
Acute viral respiratory infections (AVRI) are a leading cause of morbidity and mortality among all age groups globally. Except for Influenza virus and Respiratory Syncytial virus, mostly viral aetiology of AVRI remains undiagnosed. Lately, human coronaviruses (HCoVs) have emerged as an important aetiology of AVRI. A laboratory based retrospective cross sectional study was conducted in which respiratory samples (throat swabs) of patients (n = 864), with Influenza negative SARI, of all age groups between Jan 2011-Dec 2012 were tested for HCoVs including MERS-CoV using Conventional and real time PCR assays. The prevalence of HCoV among SARI cases was 1.04% (9/864) [95% CI: 0.36-1.72]. Of these four (44.44%) were identified as HCoV OC43, three (33.33%) as HCoV NL63 and two (22.22%) as HCoV 229E. No HCoV HKU1 was detected. The samples were also negative for SARS-CoV and MERS-CoV. The results of this study documents low prevalence of human coronaviruses in SARI cases in south western India and the absence of highly pathogenic human coronaviruses. As the study included only SARI cases the prevalence reported could be an under estimate when it is extrapolated to community.
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- 2015
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11. Human coronaviruses in severe acute respiratory infection (SARI) cases in southwest India
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Prabhu G, Suresha, Chameettachal, Akhil, Aithal, Anjali, Dsouza R, Giselle, Bhaskar, Revti, and Govindakarnavar, Arunkumar
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Adult ,Male ,Adolescent ,Coronaviridae Infections ,viruses ,Short Communication ,prevalence ,Short Communications ,India ,Polymerase Chain Reaction ,Young Adult ,MERS ,Humans ,Child ,Respiratory Tract Infections ,Retrospective Studies ,SARS ,virus diseases ,Infant ,Middle Aged ,southwest India ,Coronavirus ,Cross-Sectional Studies ,Child, Preschool ,SARI ,Pharynx ,HCoV ,Female - Abstract
Acute viral respiratory infections (AVRI) are a leading cause of morbidity and mortality among all age groups globally. Except for Influenza virus and Respiratory Syncytial virus, mostly viral aetiology of AVRI remains undiagnosed. Lately, human coronaviruses (HCoVs) have emerged as an important aetiology of AVRI. A laboratory based retrospective cross sectional study was conducted in which respiratory samples (throat swabs) of patients (n = 864), with Influenza negative SARI, of all age groups between Jan 2011–Dec 2012 were tested for HCoVs including MERS‐CoV using Conventional and real time PCR assays. The prevalence of HCoV among SARI cases was 1.04% (9/864) [95% CI: 0.36–1.72]. Of these four (44.44%) were identified as HCoV OC43, three (33.33%) as HCoV NL63 and two (22.22%) as HCoV 229E. No HCoV HKU1 was detected. The samples were also negative for SARS‐CoV and MERS‐CoV. The results of this study documents low prevalence of human coronaviruses in SARI cases in south western India and the absence of highly pathogenic human coronaviruses. As the study included only SARI cases the prevalence reported could be an under estimate when it is extrapolated to community. J. Med. Virol. 88:163–165, 2016. © 2015 Wiley Periodicals, Inc.
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- 2015
12. Consensus of mental health and well being for developing countries
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BRUCE S, DSOUZA R, DEVA P, RUIZ P, SUNDRAM S., MAJ, Mario, Bruce, S, Maj, Mario, Dsouza, R, Deva, P, Ruiz, P, and Sundram, S.
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- 2006
13. The how and why of a $10 optical coherence tomography system
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Leahy, M. J., additional, Wilson, C., additional, Hogan, J., additional, O’Brien, Peter, additional, Dsouza, R., additional, Neuhaus, K., additional, Bogue, D., additional, Subhash, H., additional, O’Riordan, Colm, additional, and McNamara, Paul M., additional
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- 2016
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14. Transient global amnesia following coronary angiography
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Udyavar, A., Dsouza, R., Gadkar, N., and Rajani, Rajesh
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- 2006
15. Phototriggered release of amine from a cucurbituril macrocycle
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Vázquez, J., primary, Romero, M. A., additional, Dsouza, R. N., additional, and Pischel, U., additional
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- 2016
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16. Human coronaviruses in severe acute respiratory infection (SARI) cases in southwest India
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Suresha, Prabhu G., primary, Akhil, Chameettachal, additional, Anjali, Aithal, additional, Giselle, Dsouza R., additional, Revti, Bhaskar, additional, and Arunkumar, Govindakarnavar, additional
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- 2015
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17. Prevalence of Hepatitis C–Related Cirrhosis in Elderly Asian Patients Infected in Childhood
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DSOUZA, R, primary, GLYNN, M, additional, USHIROLUMB, I, additional, FEAKINS, R, additional, DOMIZIO, P, additional, MEARS, L, additional, ALSCED, E, additional, KUMAR, P, additional, SABIN, C, additional, and FOSTER, G, additional
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- 2005
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18. The how and why of a $10 optical coherence tomography system
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Izatt, Joseph A., Fujimoto, James G., Tuchin, Valery V., Leahy, M. J., Wilson, C., Hogan, J., O’Brien, Peter, Dsouza, R., Neuhaus, K., Bogue, D., Subhash, H., O’Riordan, Colm, and McNamara, Paul M.
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- 2016
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19. Effect of maternal autonomy on under five child mortality in slums of Karachi, Pakistan
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DSOUZA, R, primary
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- 1998
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20. Pitfalls in acupuncture research
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DSOUZA, R
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- 1993
21. Pharmacokinetics of Sch 34343 in rats and dogs
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Lin, C., Loebenberg, D., Chung, M., Oden, E., Veals, J., Kim, H., Lim, J., Korduba, C., DSouza, R., Moss, E., Symchowicz, S., and Miller, G. H.
- Abstract
The pharmacokinetics of 14C-Sch 34343 were studied in rats and dogs following intravenous and intramuscular dosing. In both species, it was rapidly absorbed after intramuscular dosing. The serum AUC for total radioactivity and for intact drug after intramuscular dosing were similar to those obtained after intravenous dosing. Following both routes of drug administration, the elimination of half-life (T
½β ) was 7 mm in rats and 25–32 mm in dogs. Following intravenous dosing of 14C-Sch 34343 to rats, radioactivity in tissues disappeared rapidly with time indicating no tissue accumulation. Highest concentrations of radioactivity were seen in the kidney. Liver, lung, skin and heart appeared to have concentrations of radioactivity similar to those of blood. Sch 34343 was excreted rapidly and primarily into the urine in both rats and dogs. After either route of dosing, urinary excretion of total radioactivity ranged from 84 to 93% and that of intact Sch 34343 from 41 to 51% of the dose, respectively. In addition, the effect of pretreatment with probenecid on the pharmacokinetics in rats and dogs and in anephric rats were also evaluated Pretreatment with probenecid prolonged the elimination half-life in both rats and dogs. Anephric rats had a longer half-life than normal rats.- Published
- 1985
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22. Matrix Metalloproteinase-9 as a Predictor of Healing in Diabetic Foot Ulcers.
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Shetty P, Dsouza R, and Kumar B V
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Background Wound healing in diabetic foot ulcers (DFUs) is hindered by several physiological and biochemical abnormalities, including prolonged inflammation, an imbalance in extracellular matrix (ECM) synthesis and degradation, insufficient neovascularization, and reduced macrophage activity. In DFUs, excessive and uncontrolled matrix metalloproteinases (MMPs) degrade the ECM and impede wound healing. Matrix metalloproteinase-9 (MMP-9) concentration plays a key role in inflammation and ECM degradation. This study explores the relationship between wound type in DFUs and MMP-9 levels, hypothesizing that a high MMP-9 environment may indicate inflammation and impaired wound healing. Materials and methods Forty individuals with type 2 diabetes and foot ulcers were recruited for the study. The participants were divided into two groups: nonhealing and healing, with 20 patients in each group. Biopsy samples were homogenized, and MMP-9 activity was measured using an ELISA. Results The MMP-9 concentration was significantly higher in nonhealing ulcers compared to healing ulcers. Receiver operating characteristic analysis revealed that MMP-9 measurement was the most accurate predictor of wound healing, with an area under the curve value of 0.945 and high sensitivity and specificity. Although there was a weak correlation between MMP-9 concentration and glycosylated hemoglobin, it was not statistically significant. Conclusions MMP-9 expression serves as a marker of poor wound healing. MMP-9 levels in the wound at the time of presentation may predict the healing trajectory and help tailor a specific treatment plan for each DFU patient., Competing Interests: Human subjects: Consent for treatment and open access publication was obtained or waived by all participants in this study. Ethics Committee of Father Muller Medical College issued approval FMIEC/CCM/711/2020. This research project has been reviewed and approved. Animal subjects: All authors have confirmed that this study did not involve animal subjects or tissue. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: This work was supported by the Advance Research Department, Rajiv Gandhi University of Health Sciences,Grant number 20MED255. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Shetty et al.)
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- 2024
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23. Ultrafast signatures of merocyanine overcoming steric impedance in crystalline spiropyran.
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Siddiqui KM, Bittmann SF, Hayes SA, Krawczyk KM, Sarracini A, Corthey G, Dsouza R, and Miller RJD
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Isomerisation through stereochemical changes and modulation in bond order conjugation are processes that occur ubiquitously in diverse chemical systems and for photochromic spirocompounds, it imparts them their functionality as phototransformable molecules. However, these transformations have been notoriously challenging to observe in crystals due to steric hindrance but are necessary ingredients for the development of reversible spiro-based crystalline devices. Here, we report the detection of spectroscopic signatures of merocyanine due to photoisomerisation within crystalline spiropyran following 266 nm excitation. Our femtosecond spectroscopy experiments reveal bond breaking, isomerisation and increase in bond order conjugation towards the formation of merocynine on a sub-2 ps time scale. They further unveil a lifetime of several picoseconds for the initial open ring intermediate with subsequent relaxation to mercocyanine, with established back connversion pathways, which make the system highly reversible in the solid state. Supporting femtosecond electron diffraction studies suggest that lattice strain favours the return of photoproduct to the closed spiroform. Our work thus paves the way for novel ultrafast applications from spiropyran-derived compounds., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)
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- 2024
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24. Pseudo hepatic vein thrombosis in a newborn with infracardiac total anomalous pulmonary venous connection.
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DSouza R, Kuruvilla Thomas S, Patharateeranart K, Seed M, Lam CZ, and Yoo SJ
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- Humans, Infant, Newborn, Diagnosis, Differential, Scimitar Syndrome diagnostic imaging, Pulmonary Veins diagnostic imaging, Pulmonary Veins abnormalities, Male, Incidental Findings, Female, Hepatic Veins diagnostic imaging, Hepatic Veins abnormalities, Venous Thrombosis diagnostic imaging, Tomography, X-Ray Computed methods
- Abstract
We report an interesting incidental liver finding during ECG-gated cardiac computed tomography (CT) in a newborn with infracardiac total anomalous pulmonary venous connection to the portal vein. This case shows a unique abnormality in hepatic perfusion that was initially mistaken for hepatic vein thrombosis. We review the altered hepatic blood flow distribution in this pathologic anatomy to help explain the observed hepatic perfusion abnormality on CT. This understanding will enable an imager to anticipate hepatic perfusion patterns in similar patients, potentially avoiding misdiagnosis and unnecessary further testing., Competing Interests: Declarations. Consent: Patient consent has been obtained. Conflicts of interest: None, (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
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- 2024
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25. Severe burns in a resource-limited rural healthcare centre.
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Masih S, Dsouza R, and Goldstein AL
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- Adult, Female, Humans, Burn Units, Fatal Outcome, India, Burns therapy, Rural Health Services, Resource-Limited Settings
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A woman in her mid-30s presented to our 30-bed healthcare centre with extensive burns, hours after falling into a shallow pit of burning dried tea leaves. On arrival, there was no evidence of airway compromise. She was fully conscious but had signs of shock and hypovolemia. Forty-five per cent of the total body surface area was burned, including the face, neck, thorax, abdomen, upper limbs and thighs. The family refused referral to a burns centre and insisted on continuing treatment at our facility. Our hospital, not equipped to manage burns, was adapted to deliver effective, immediate care. After initial stabilisation, the patient was unwilling to remain hospitalised because of her husband's employment commitment. Subsequently, we were notified that the patient died within 1 month of discharge. This article highlights the importance of burns care facilities in rural India and the impact of a failure to access quality health on outcomes., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2024. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2024
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26. Benign ectopic prostate-a rare differential for a presacral mass.
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Dsouza R, A R, Mathew A, and Raghunath R
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- Humans, Male, Diagnosis, Differential, Adult, Prostate pathology, Prostate diagnostic imaging, Prostate surgery, Choristoma surgery, Choristoma diagnosis, Choristoma diagnostic imaging, Magnetic Resonance Imaging
- Abstract
A man in his mid-40s presented to the colorectal surgery clinic with complaints of chronic perianal pain for over 20 years. He had episodes of urinary incontinence associated with pain. There were no other symptoms to suspect bowel pathology. On examination, he was found to have a tender mass in the retro-rectal plane without any evidence of rectal mucosal irregularity. He underwent an MRI of the pelvis, which showed a well-defined T2 hyperintense partly cystic lesion in the presacral region abutting the mesorectal fascia and a normal prostate gland. With a suspicion of a tailgut cyst or a duplication cyst, he underwent an excision of the presacral mass. Intraoperatively, there was a 2 × 2 cm well-defined firm, cystic lesion anterior to the fifth sacral vertebra and coccyx. The lesion was adherent to the mesorectum and was excised. On histopathology, there were features of muscular stroma and bilayered glandular epithelium with clear cytoplasm conclusive of a benign ectopic prostate., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2024. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2024
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27. Delayed three-dimensional inversion recovery-prepared fast low-angle shot for airway imaging in children: More than myocardial fibrosis assessment.
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Acosta Izquierdo L, Dsouza R, Saprungruang A, Amirabadi A, Seed M, Yoo SJ, and Lam CZ
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- Humans, Child, Retrospective Studies, Female, Child, Preschool, Male, Adolescent, Reproducibility of Results, Age Factors, Myocardium pathology, Cardiac-Gated Imaging Techniques, Infant, Magnetic Resonance Imaging, Cine, Magnetic Resonance Imaging, Predictive Value of Tests, Fibrosis, Imaging, Three-Dimensional
- Abstract
Background: To investigate the ability of a delayed respiratory-navigated, electrocardiographically-gated three-dimensional inversion recovery-prepared fast low-angle shot (3D IR FLASH) sequence to evaluate the lower airways in children undergoing routine cardiovascular magnetic resonance (CMR)., Methods: This retrospective study included pediatric patients (0-18 years) who underwent clinical CMR where a delayed 3D IR FLASH sequence was performed between July 2020 and April 2021. The airway image quality and extent of lower airway visibility were graded by two blinded readers using a four-point ordinal scale (0-3). Lower airway anatomical variants and abnormalities were recorded., Results: One hundred and eighty patients were included with a median age of 11.7 (4.6-15.3) years. Fifty-one of 180 (28%) were under general anesthesia. Overall, the median grading of airway image quality was 3 (2-3) and the extent of lower airway visibility was 3 (3-3). Interrater agreement was almost perfect (κ = 0.867 and κ = 0.956, respectively). Image quality correlated with extent of lower airway visibility (r = 0.62, p < 0.01). Delayed 3D IR FLASH was able to characterize the segmental bronchi in 137/180 (76%) and lobar bronchi in 172/180 (96%) of patients. Lower airway abnormalities were identified in 37/180 (21%) of patients and 33/129 (26%) with congenital heart disease (CHD). Identified abnormalities included tracheobronchial branching anomalies in 6/180 (3%), abnormal tracheobronchial situs in 6/180 (3%), and extrinsic vascular compression in 25/180 (14%)., Conclusion: Delayed 3D IR FLASH has excellent performance for evaluation of the lower airway anatomy and can simultaneously assess for myocardial late gadolinium enhancement. Lower airway abnormalities are not infrequently seen in children undergoing routine CMR for CHD., Competing Interests: Declaration of competing interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)
- Published
- 2024
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28. Prognostic value of myocardial deformation parameters for outcome prediction in tetralogy of Fallot.
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Thomas SK, DSouza R, Hanneman K, Karur GR, Houbois C, Ishikita A, D'Errico L, Begun I, Ng MY, and Wald RM
- Subjects
- Humans, Male, Female, Adult, Risk Factors, Treatment Outcome, Middle Aged, Young Adult, Time Factors, Cardiac Surgical Procedures adverse effects, Cardiac Surgical Procedures mortality, Risk Assessment, Retrospective Studies, Heart Valve Prosthesis Implantation adverse effects, Heart Valve Prosthesis Implantation mortality, Myocardial Contraction, Recovery of Function, Tetralogy of Fallot physiopathology, Tetralogy of Fallot surgery, Tetralogy of Fallot diagnostic imaging, Tetralogy of Fallot mortality, Predictive Value of Tests, Ventricular Function, Left, Ventricular Function, Right, Ventricular Remodeling, Magnetic Resonance Imaging, Cine, Registries, Pulmonary Valve Insufficiency physiopathology, Pulmonary Valve Insufficiency diagnostic imaging, Pulmonary Valve Insufficiency etiology, Pulmonary Valve Insufficiency surgery, Pulmonary Valve Insufficiency mortality
- Abstract
Background: The prognostic value of myocardial deformation parameters in adults with repaired tetralogy of Fallot (rTOF) has not been well-elucidated. We therefore aimed to explore myocardial deformation parameters for outcome prediction in adults with rTOF using cardiovascular magnetic resonance imaging (CMR)., Methods: Adults with rTOF and at least moderate pulmonary regurgitation were identified from an institutional prospective CMR registry. Left ventricular (LV) and right ventricular (RV) global strains were recorded in longitudinal (GLS), circumferential (GCS), and radial (GRS) directions. Major adverse cardiovascular events (MACE) were defined as a composite of mortality, resuscitated sudden death, sustained ventricular tachycardia (>30 seconds), or heart failure (hospital admission >24 hours). In patients with pulmonary valve replacement (PVR), pre- and post-PVR CMR studies were analyzed to assess for predictors of complete RV reverse remodeling, defined as indexed RV end-diastolic volume (RVEDVi) <110 mL/m
2 . Logistic regression models were used to estimate the odds ratio (OR) per unit change in absolute strain value associated with clinical outcomes and receiver operator characteristic curves were constructed with area under the curve (AUC) for select CMR variables., Results: We included 307 patients (age 35 ± 13 years, 59% (180/307) male). During 6.1 years (3.3-8.8) of follow-up, PVR was performed in 142 (46%) and MACE occurred in 31 (10%). On univariate analysis, baseline biventricular ejection fraction (EF), mass, and all strain parameters were associated with MACE. After adjustment for LVEF, only LV-GLS remained independently predictive of MACE (OR 0.822 [0.693-0.976] p = 0.025). Receiver operator curves identified an absolute LV-GLS value less than 15 and LVEF less than 51% as thresholds for MACE prediction (AUC 0.759 [0.655-0.840] and 0.720 [0.608-0.810]). After adjusting for baseline RVEDVi, RV-GCS (OR 1.323 [1.094-1.600] p = 0.004), LV-GCS (OR 1.276 [1.029-1.582] p = 0.027) and LV-GRS (OR 1.101 [1.0210-1.200], p = 0.028) were independent predictors of complete remodeling post-PVR remodeling., Conclusion: Biventricular strain parameters predict clinical outcomes and post-PVR remodeling in rTOF. Further study will be necessary to establish the role of myocardial deformation parameters in clinical practice., Competing Interests: Declaration of competing interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)- Published
- 2024
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29. Quantitative three-dimensional imaging of chemical short-range order via machine learning enhanced atom probe tomography.
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Li Y, Wei Y, Wang Z, Liu X, Colnaghi T, Han L, Rao Z, Zhou X, Huber L, Dsouza R, Gong Y, Neugebauer J, Marek A, Rampp M, Bauer S, Li H, Baker I, Stephenson LT, and Gault B
- Abstract
Chemical short-range order (CSRO) refers to atoms of specific elements self-organising within a disordered crystalline matrix to form particular atomic neighbourhoods. CSRO is typically characterized indirectly, using volume-averaged or through projection microscopy techniques that fail to capture the three-dimensional atomistic architectures. Here, we present a machine-learning enhanced approach to break the inherent resolution limits of atom probe tomography enabling three-dimensional imaging of multiple CSROs. We showcase our approach by addressing a long-standing question encountered in body-centred-cubic Fe-Al alloys that see anomalous property changes upon heat treatment. We use it to evidence non-statistical B
2 -CSRO instead of the generally-expected D03 -CSRO. We introduce quantitative correlations among annealing temperature, CSRO, and nano-hardness and electrical resistivity. Our approach is further validated on modified D03 -CSRO detected in Fe-Ga. The proposed strategy can be generally employed to investigate short/medium/long-range ordering phenomena in different materials and help design future high-performance materials., (© 2023. The Author(s).)- Published
- 2023
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30. Laparoscopic Versus Open Pre-Treatment Loop Colostomy for Fecal Diversion in Rectal Cancer Patients: Is Laparoscopic Colostomy Better?
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Varghese G, Shankar B, Dsouza R, and Jesudason MR
- Abstract
Diversion colostomy plays a crucial role in the management of carcinoma rectum in low- and middle-income countries as significant number of patients present with partial intestinal obstruction. The aim of this study was to compare laparoscopic and open approaches for fecal diversion done in patients with adenocarcinoma of the rectum as a pretreatment procedure. The primary end point of our study was time to initiation of neoadjuvant chemo radiation. It was a retrospective study that included all patients diagnosed to have carcinoma rectum and underwent a pretreatment fecal diversion between 2012 and 2014. A total of 55 patients underwent pretreatment diversion colostomy of which 33 were performed via the laparoscopic approach while 22 had open diversion. The time for initiation of neoadjuvant therapy was shorter in the laparoscopic group compared to the open approach (16 days vs. 20.5 days, P = 0.31). The study concluded that pretreatment diversion colostomy using the laparoscopic approach was a safe option in low- and middle-income countries as it was associated with faster recovery and early initiation of neoadjuvant therapy in patients with partially obstructed locally advanced carcinoma rectum., Competing Interests: Conflict of InterestThe authors declare that they have no conflict of interest., (© Indian Association of Surgical Oncology 2020.)
- Published
- 2023
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31. Strategic and contested use of food laws to ban smokeless tobacco products in India: a qualitative analysis of litigation.
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Dsouza R and Bhojani U
- Subjects
- Humans, Smoking, Legislation, Food, India, Tobacco Use, Tobacco, Smokeless, Tobacco Industry, Tobacco Products
- Abstract
Objective: To understand how food laws are used, contested and interpreted to ban certain forms of chewing tobacco in India., Methods: A qualitative study analysing all the tobacco-related litigation under the food laws in India. We used an inductive thematic analysis of the litigation contents., Results: The tobacco industry systematically deployed litigation to (1) challenge the categorisation of smokeless tobacco products as food, and hence, questioned the use of food laws for regulating these products; (2) challenge the regulatory power of the state government in banning tobacco products via the food laws; and (3) challenge the applicability of the general food laws that enabled stricter regulations beyond what is prescribed under the tobacco-specific law., Conclusion: Despite facing several legal challenges from the tobacco industry, Indian states optimised food laws to enable stricter regulations on smokeless tobacco products than were feasible through use of a tobacco-specific law., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2023
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32. Systematic Review on Diagnostic Reference Levels for Computed Tomography Examinations in Radiation Therapy Planning.
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Rao S, Sharan K, Sukumar S, Chandraguthi SG, Nisha Dsouza R, David LR, Ravichandran S, Uzun B, Kadavigere R, and Uzun Ozsahin D
- Abstract
Background : In August 2017, the European Commission awarded the "European Study on Clinical Diagnostic Reference Levels (DRL) for X-ray Medical Imaging" project to the European Society of Radiology to provide up-to-date Diagnostic Reference Levels based on clinical indications. This work aimed to conduct an extensive literature review by analyzing the most recent studies published and the data provided by the National Competent Authorities to understand the current situation regarding Diagnostic Reference Levels based on clinical indications for Radiation Therapy Computed Tomography. Objective : To review the literature on established DRLs and methodologies for establishing Diagnostic reference levels in radiation therapy planning computed tomography (RTCT). Methods : Eligibility criteria: A cohort study (observational design) reporting DRLs in adult patients undergoing computed tomography (CT) for radiation therapy for the region head and neck or pelvis were included. The comprehensive literature searches for the relevant studies published between 2000 and 2021 were performed using PubMed, Scopus, CINHAL, Web of Science, and ProQuest. Results : Three hundred fifty-six articles were identified through an extensive literature search. Sixty-eight duplicate reports were removed. The title and abstract of 288 studies were assessed and excluded if they did not meet the inclusion criteria. Sixteen of 288 articles were selected for full-text screening (studies conducted between 2000 and 2021). Five articles were included in the review after the full-text screening. Conclusions : A globally approved standard protocol that includes scanning techniques, dose measurement method, and DRL percentile needs to be established to make a valuable and accurate comparison with international DRLs.
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- 2023
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33. Slow progression of pediatric HIV associates with early CD8+ T cell PD-1 expression and a stem-like phenotype.
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Vieira V, Lim N, Singh A, Leitman E, Dsouza R, Adland E, Muenchhoff M, Roider J, Marin Lopez M, Carabelli J, Giandhari J, Groll A, Jooste P, Prado JG, Thobakgale C, Dong K, Kiepiela P, Prendergast AJ, Tudor-Williams G, Frater J, Walker BD, Ndung'u T, Ramsuran V, Leslie A, Kløverpris HN, and Goulder P
- Subjects
- Humans, CD4-Positive T-Lymphocytes, CD8-Positive T-Lymphocytes, Phenotype, HIV Infections, Programmed Cell Death 1 Receptor metabolism
- Abstract
HIV nonprogression despite persistent viremia is rare among adults who are naive to antiretroviral therapy (ART) but relatively common among ART-naive children. Previous studies indicate that ART-naive pediatric slow progressors (PSPs) adopt immune evasion strategies similar to those described in natural hosts of SIV. However, the mechanisms underlying this immunophenotype are not well understood. In a cohort of early-treated infants who underwent analytical treatment interruption (ATI) after 12 months of ART, expression of PD-1 on CD8+ T cells immediately before ATI was the main predictor of slow progression during ATI. PD-1+CD8+ T cell frequency was also negatively correlated with CCR5 and HLA-DR expression on CD4+ T cells and predicted stronger HIV-specific T lymphocyte responses. In the CD8+ T cell compartment of PSPs, we identified an enrichment of stem-like TCF-1+PD-1+ memory cells, whereas pediatric progressors and viremic adults had a terminally exhausted PD-1+CD39+ population. TCF-1+PD-1+ expression on CD8+ T cells was associated with higher proliferative activity and stronger Gag-specific effector functionality. These data prompted the hypothesis that the proliferative burst potential of stem-like HIV-specific cytotoxic cells could be exploited in therapeutic strategies to boost the antiviral response and facilitate remission in infants who received early ART with a preserved and nonexhausted T cell compartment.
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- 2023
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34. Energy landscapes from cryo-EM snapshots: a benchmarking study.
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Dsouza R, Mashayekhi G, Etemadpour R, Schwander P, and Ourmazd A
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- Protein Conformation, Cryoelectron Microscopy, Motion, Algorithms
- Abstract
Biomolecules undergo continuous conformational motions, a subset of which are functionally relevant. Understanding, and ultimately controlling biomolecular function are predicated on the ability to map continuous conformational motions, and identify the functionally relevant conformational trajectories. For equilibrium and near-equilibrium processes, function proceeds along minimum-energy pathways on one or more energy landscapes, because higher-energy conformations are only weakly occupied. With the growing interest in identifying functional trajectories, the need for reliable mapping of energy landscapes has become paramount. In response, various data-analytical tools for determining structural variability are emerging. A key question concerns the veracity with which each data-analytical tool can extract functionally relevant conformational trajectories from a collection of single-particle cryo-EM snapshots. Using synthetic data as an independently known ground truth, we benchmark the ability of four leading algorithms to determine biomolecular energy landscapes and identify the functionally relevant conformational paths on these landscapes. Such benchmarking is essential for systematic progress toward atomic-level movies of continuous biomolecular function., (© 2023. The Author(s).)
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- 2023
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35. Breast reconstruction following mastectomy in Indian women: a neglected entity.
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Dsouza R, Gaikwad P, Samuel VM, and Thomas C
- Subjects
- Female, Humans, Mastectomy methods, Surgical Flaps blood supply, Breast Neoplasms surgery, Mammaplasty methods, Phyllodes Tumor pathology
- Abstract
Phyllodes tumour is a rapidly growing neoplasm with a propensity to involve the entire breast tissue. In large tumours, the treatment comprises a wide local excision or a mastectomy. A woman in her 20s from rural India presented with complaints of a recurrent left breast lump. The lump progressed to a large size, limiting her social activities and causing depression. On examination, she had a mass occupying almost the entire left breast, with stretched skin, dilated veins and pressure necrosis. There were no palpable axillary nodes. She was offered a wide local excision and reconstruction with a latissimus dorsi pedicled flap. After much discussion and clarification of some misconceptions around breast reconstruction, she underwent the planned surgery. This was followed by adjuvant radiation therapy as the histopathology was consistent with a complex phyllodes tumour with close margins. She was well at 1-year follow-up and led a good family and social life. Breast conservation and reconstruction are seldom offered as part of cancer treatment in India. All women should be offered surgical options that are oncologically safe while preserving body image, and hence healthcare providers must work towards breaking the barriers that prevent breast reconstruction., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2022. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2022
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36. Head biomechanics of video recorded falls involving children in a childcare setting.
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Bertocci G, Smalley C, Brown N, Dsouza R, Hilt B, Thompson A, Bertocci K, McKinsey K, Cory D, and Pierce MC
- Subjects
- Biomechanical Phenomena, Body Height, Child, Child, Preschool, Head, Humans, Infant, Acceleration, Child Care
- Abstract
The objective of this study was to characterize head biomechanics of video-recorded falls involving young children in a licensed childcare setting. Children 12 to < 36 months of age were observed using video monitoring during daily activities in a childcare setting (in classrooms and outdoor playground) to capture fall events. Sensors (SIM G) incorporated into headbands worn by the children were used to obtain head accelerations and velocities during falls. The SIM G device was activated when linear acceleration was ≥ 12 g. 174 video-recorded falls activated the SIM G device; these falls involved 31 children (mean age = 21.6 months ± 5.6 SD). Fall heights ranged from 0.1 to 1.2 m. Across falls, max linear head acceleration was 50.2 g, max rotational head acceleration was 5388 rad/s
2 , max linear head velocity was 3.8 m/s and max rotational head velocity was 21.6 rad/s. Falls with head impact had significantly higher biomechanical measures. There was no correlation between head acceleration and fall height. No serious injuries resulted from falls-only 1 child had a minor injury. In conclusion, wearable sensors enabled characterization of head biomechanics during video-recorded falls involving young children in a childcare setting. Falls in this setting did not result in serious injury., (© 2022. The Author(s).)- Published
- 2022
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37. Prognostic significance of MR identified EMVI, tumour deposits, mesorectal nodes and pelvic side wall disease in locally advanced rectal cancer.
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Chandramohan A, Mittal R, Dsouza R, Yezzaji H, Eapen A, Simon B, John R, Singh A, Ram TS, Jesudason MR, Masih D, and Karuppusami R
- Subjects
- Extranodal Extension, Female, Humans, Lymphatic Metastasis, Magnetic Resonance Imaging methods, Male, Middle Aged, Neoadjuvant Therapy, Neoplasm Invasiveness pathology, Neoplasm Staging, Prognosis, Retrospective Studies, Neoplasms, Second Primary pathology, Rectal Neoplasms diagnostic imaging, Rectal Neoplasms pathology, Rectal Neoplasms therapy
- Abstract
Aim: To study the prognostic significance of MRI identified tumour deposits (TD), extramural vascular invasion (EMVI), lymph node metastases (LNM) and pelvic sidewall (PSW) disease in rectal cancer., Methods: This IRB approved study was conducted on patients with stage IIA-IIIC rectal adenocarcinoma treated with neoadjuvant long course chemoradiotherapy (LCCRT) and total mesorectal excision (TME) type of surgery between 2012-2018. A radiologist blinded to outcome reviewed staging and restaging magnetic resonance imaging (MRI) for TD, EMVI, LNM and PSW. The agreement between four radiologists was studied and we obtained outcome data from a prospectively maintained database. The prognostic significance of imaging findings was assessed., Results: A total of 297 (186 males) patients with a mean age of 47.3 (SD14.4) years were included in the study. The majority had T3 (n = 206) or T4 (n = 59) stage disease. The mean duration of follow-up was 49.3 ± 25 months (6.6-101 months). 5-year overall (OS) and disease-free survival (DFS) was 84% and 74%, respectively. Staging and restaging MRI had EMVI in 49.5% and 31.3%; TD in 47.5% and 31.6%; LNM in 61.1% and 38.1% and PSW in 11.4% and 6.1%. OS was adversely affected by EMVI, TD and PSW with the adjusted HR (aHR) of 3.32, 3.31, 3.27 for staging MRI and 2.99, 3.1, 2.81 for restaging MRI, respectively, p < 0.05. DFS was affected by EMVI (aHR = 1.85, 2.33) and TD (aHR = 1.83, 2.19), p < 0.05. Persistence of these findings after LCCRT led to worst outcome. Intra- and interobserver agreement for EMVI, TD and LN was 0.789, 0.734, 0.406 and 0.449, 0.354, 0.376, respectively, p < 0.001., Conclusions: MRI identified that TD, EMVI and PSW disease are independent poor prognostic indicators in rectal cancer patients. Interobserver agreement for these findings was moderate to fair., (© 2021 The Association of Coloproctology of Great Britain and Ireland.)
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- 2022
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38. Legal Challenges in Tobacco Control: Historical and Qualitative Analysis of Litigations in Karnataka.
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Dsouza R, Bhojani U, Joseph N, Prabhakara P, and Selvarajan M
- Abstract
Background: Tobacco use is a major cause of disease and death in India. Karnataka, a southern Indian state with 12 million tobacco users has a fair share of this burden. The Government of Karnataka has used an ensemble of regulations to reduce tobacco use. Studies indicate that litigations have been used by the tobacco industry to challenge tobacco control regulations at the national level. There is a dearth of studies on how litigations have been used at a state level., Objectives: To historically analyse the tobacco-related litigations so as to better understand how laws/regulations have been used and contested by various stakeholders in advancing or resisting the tobacco control efforts in Karnataka., Methods: We used a retrospective qualitative analysis of tobacco-related litigations adjudicated by the Karnataka High court. We systematically searched a legal database and selected 39 litigations for analysis. We mapped these cases in a spreadsheet and used thematic content analysis of the court judgements., Results: Our study demonstrated that tobacco regulations and legal challenges arise from a range of laws related to food, pharmaceuticals, municipal affairs and taxation in addition to tobacco-specific laws. We found that tobacco regulations have been intensely litigated, predominantly by parties with commercial interests in tobacco that resisted these regulations. Comparatively, there were very few litigations from public health advocates demanding stricter tobacco control regulations., Conclusion: Analysis of litigations helps in identifying legal challenges that inform tobacco control authorities to anticipate and prepare for future challenges in implementing tobacco control regulations. Tobacco control agencies need adequate legal personnel and resources to effectively respond to these challenges., Competing Interests: Conflict of Interests UB is a member of the Advisory Board of the HGJ Health Policy Research. The authors declare no conflict of interest for this work.
- Published
- 2022
39. Development of a Smartphone-Based Skin Simulation Model for Medical Education.
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Dsouza R, Spillman DR Jr, Barrows S, Golemon T, and Boppart SA
- Subjects
- Computer Simulation, Humans, Smartphone, Education, Medical, Mobile Applications, Students, Medical
- Abstract
Introduction: Teaching dermatology to medical students entails a series of lectures, pictures, and hands-on skin examinations to convey a sense of skin features and textures, often by use of simulated skin models. However, such methods can often lack accurate visual and tactile texture representation of skin lesions. To facilitate learning, we have developed a smartphone-based skin simulation model, which provides a configurable visual and tactile sense of a lesion by using the ubiquitous availability of smartphone-based mobile platforms., Methods: A polydimethylsiloxane (PDMS) overlay was used as a configurable translucent elastomer material to model the stiffness and texture of skin. A novel custom smartphone-based app was developed to capture images of various skin lesions, which were subsequently displayed on a tablet or second smartphone, over which the PDMS model skin elastomer was placed. Using the local Bluetooth connection between mobile devices, an iterative feedback algorithm corrected the visual distortion caused by the optical scattering of the translucent elastomer, enabling better virtual visualization of the lesion., Results: The developed smartphone-based app corrected the distortion of images projected through the simulated skin elastomer. Surface topography of the developed PDMS elastomer provided a more accurate representation of skin texture., Conclusions: In this investigation, we developed a smartphone-based skin lesion visualization app with a simulated skin elastomer for training/education in not only dermatology but also all general medical specialties that examine the skin. This technique has the potential to advance the educational experience by giving students the ability to see, touch, and feel pragmatic skin textures and lesions., Competing Interests: The authors declare no conflict of interest., (Copyright © 2020 Society for Simulation in Healthcare.)
- Published
- 2021
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40. External environmental agents influence telomere length and telomerase activity by modulating internal cellular processes: Implications in human aging.
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Fernandes SG, Dsouza R, and Khattar E
- Subjects
- Aging metabolism, Animals, Cell Physiological Phenomena drug effects, Humans, Environmental Pollutants toxicity, Telomerase metabolism, Telomere drug effects
- Abstract
External environment affects cellular physiological processes and impact the stability of our genome. The most important structural components of our linear chromosomes which endure the impact by these agents, are the chromosomal ends called telomeres. Telomeres preserve the integrity of our genome by preventing end to end fusions and telomeric loss through by inhibiting DNA damage response (DDR) activation. This is accomplished by the presence of a six membered shelterin complex at telomeres. Further, telomeres cannot be replicated by normal DNA polymerase and require a special enzyme called telomerase which is expressed only in stem cells, few immune cells and germ cells. Telomeres are rich in guanine content and thus become extremely prone to damage arising due to physiological processes like oxidative stress and inflammation. External environmental factors which includes various physical, biological and chemical agents also affect telomere homeostasis by increasing oxidative stress and inflammation. In the present review, we highlight the effect of these external factors on telomerase activity and telomere length. We also discuss how the external agents affect the physiological processes, thus modulating telomere stability. Further, we describe its implication in the development of aging and its related pathologies., (Copyright © 2021 Elsevier B.V. All rights reserved.)
- Published
- 2021
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41. Microscale sensor solution for data collection from fibre-matrix interfaces.
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Dsouza R, Antunes P, Kakkonen M, Tanhuanpää O, Laurikainen P, Javanshour F, Kallio P, and Kanerva M
- Abstract
Especially the applications of fibrous composites in miniature products, dental and other medical applications require accurate data of microscale mechanics. The characterization of adhesion between single filament and picoliter-scale polymer matrix usually relies on the experiments using so-called microbond (MB) testing. The traditional MB test systems provide unitary data output (i.e., converted force) which is enigmatic in resolving the fracture parameters of multi-mode interface cracks. As a fundamental basis, the momentary reaction force and respective local strain at the location of a non-ambiguous gradient are needed for a mechanical analysis. In this paper, a monolithic compliant based structure with an integrated Fiber Bragg Grating (FBG) sensor is developed and analysed. The stiffness of the compliant structure is estimated by using mathematical and finite element (FE) models. Qualification experiments are carried out to confirm the functional performance: MB testing of synthetic (carbon and glass) and natural (flax) single filaments are successfully performed. Quasi-static and dynamic analysis of the MB testing is carried out by using the FE method to interpret the response of the compliant structure. The developed strain-sensing CBPM-FBG holder shows excellent sensitivity during the MB tests for both synthetic and natural filaments, even at a low filament diameters as low as [Formula: see text], making the monolithic compliant structure the first instrument capable of force-strain data output for bonded filament-droplet specimens.
- Published
- 2021
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42. Bilateral mammary hibernoma mimicking breast carcinoma: a diagnostic challenge.
- Author
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Dsouza R, Cherian AJ, Ananthakrishnan R, and Menon N
- Subjects
- Aged, Breast diagnostic imaging, Female, Humans, Neoplasm Recurrence, Local, Ultrasonography, Mammary, Breast Neoplasms diagnostic imaging, Breast Neoplasms surgery, Lipoma diagnostic imaging, Lipoma surgery
- Abstract
We describe a 68-year-old postmenopausal woman who presented with a history of rapidly enlarging lumps in both breasts. Though the breast lumps appeared suspicious on ultrasonography, the core biopsy was reported to be benign. In view of the clinical and radiological suspicion of malignancy, she underwent a diagnostic excision of both the lumps, the histopathology was consistent with mammary hibernoma. To the best of the authors' knowledge, this is the first report of a bilateral mammary hibernoma in an elderly postmenopausal woman. Given the clinical presentation, it is important to differentiate mammary hibernoma from carcinoma breast, which is a more common condition in this age group. However, preoperative diagnosis is challenging in view of the lack of definitive radiological and histological features. Although benign, hibernoma may have a propensity for local recurrence and, therefore, complete surgical excision remains the mainstay of treatment., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2021. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2021
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43. Efficacy of endotracheal tube suctioning in intubated intensive care unit patients determined by in vivo catheter-based optical coherence tomography-a pilot study.
- Author
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Dsouza R, Spillman DR Jr, Barkalifa R, Monroy GL, Chaney EJ, Johnson MA, White KC, and Boppart SA
- Abstract
Background: Mechanical ventilation using an endotracheal tube (ETT) is one of the critical interventions given to patients in the intensive care unit (ICU). ETTs are associated with the formation of biofilms, placing patients at increased risk for developing ventilator-associated pneumonia (VAP). ETT suctioning is used to remove secretions, reduce bacterial colonization, and reduce the rate of biofilm formation. However, current standard-of-care suctioning procedures do not adequately eliminate all secretions from the ETT., Methods: This observational study was conducted in a cohort of 4 subjects admitted to the ICU and intubated with an ETT, irrespective of ethnicity, gender, or race. A total of 23 suctioning procedures were evaluated with in vivo three-dimensional (3D) optical coherence tomography (OCT) imaging, before and after suctioning. A secretion density metric was derived from the OCT data to quantify the amount of secretions present within the ETT, and an attenuation coefficient metric was derived to detect and quantify the presence of biofilms. Analyzed OCT images were correlated with clinical and microscopy data., Results: Data obtained suggests that the current standard-of-care suctioning procedure is inefficient at clearing secretions or preventing the formation of biofilms. The presence of biofilms was corroborated with both post-intubation microscopy of the ETTs, as well as with clinical data., Conclusions: We conclude that the standard-of-care suctioning method does not eliminate secretions nor reduce the formation of biofilm in ETTs. Our in situ imaging method was sensitive to the presence of secretions, biofilms, and quantitative, and can be used for investigating different suctioning protocols in the future., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at http://dx.doi.org/10.21037/qims-20-549). SAB is co-founder and Chief Medical Officer of PhotoniCare, Inc., which is developing optical imaging systems for the ear, and Diagnostic Photonics, Inc., which is developing optical imaging systems for cancer detection. SAB also reports intellectual property owned by the University of Illinois at Urbana-Champaign related to optical coherence tomography, and licensed to commercial entities. SAB reports grants from NIH, during the conduct of the study. RD reports grants from NIH, during the conduct of the study. DRSJ reports grants from NIH, during the conduct of the study; grants from NIH, outside the submitted work; RB reports grants from NIH, during the conduct of the study. GLM reports grants from NIH, during the conduct of the study. EJC reports grants from NIH, during the conduct of the study. MAJ reports grants from NIH, during the conduct of the study. KCW reports grants from NIH, during the conduct of the study., (2021 Quantitative Imaging in Medicine and Surgery. All rights reserved.)
- Published
- 2021
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44. Role of Telomeres and Telomeric Proteins in Human Malignancies and Their Therapeutic Potential.
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Fernandes SG, Dsouza R, Pandya G, Kirtonia A, Tergaonkar V, Lee SY, Garg M, and Khattar E
- Abstract
Telomeres are the ends of linear chromosomes comprised of repetitive nucleotide sequences in humans. Telomeres preserve chromosomal stability and genomic integrity. Telomere length shortens with every cell division in somatic cells, eventually resulting in replicative senescence once telomere length becomes critically short. Telomere shortening can be overcome by telomerase enzyme activity that is undetectable in somatic cells, while being active in germline cells, stem cells, and immune cells. Telomeres are bound by a shelterin complex that regulates telomere lengthening as well as protects them from being identified as DNA damage sites. Telomeres are transcribed by RNA polymerase II, and generate a long noncoding RNA called telomeric repeat-containing RNA (TERRA), which plays a key role in regulating subtelomeric gene expression. Replicative immortality and genome instability are hallmarks of cancer and to attain them cancer cells exploit telomere maintenance and telomere protection mechanisms. Thus, understanding the role of telomeres and their associated proteins in cancer initiation, progression and treatment is very important. The present review highlights the critical role of various telomeric components with recently established functions in cancer. Further, current strategies to target various telomeric components including human telomerase reverse transcriptase (hTERT) as a therapeutic approach in human malignancies are discussed.
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- 2020
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45. Diabetic Retinopathy and Anemia: Is There a Treatable Nutritional element?
- Author
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J C, DSouza R, Mathew KG, Muralidharan J, Nithyanandam S, Joseph M, and Idiculla J
- Subjects
- Humans, Anemia, Diabetes Mellitus, Type 2, Diabetic Retinopathy
- Published
- 2020
46. Crohn's disease associated adenocarcinoma of ileocaecal region: a miscalculated approach.
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Dsouza R, Varghese G, Korula DR, and Dutta AK
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- Adenocarcinoma etiology, Adult, Cecal Neoplasms etiology, Female, Humans, Ileal Neoplasms etiology, Adenocarcinoma surgery, Cecal Neoplasms surgery, Crohn Disease complications, Ileal Neoplasms surgery
- Abstract
Adenocarcinoma of the bowel is a dreadful sequelae of inflammatory bowel disease that can be difficult to diagnose and has been shown to have poor prognosis. The diagnosis is often made on histopathological examination of the resected specimen for what is suspected to be an exacerbation of the underlying intestinal Crohn's. A 39-year-old woman who was being treated for small bowel Crohn's disease for 4 years presented with features of intermittent intestinal obstruction that was refractory to medical therapy. A contrast CT of the abdomen was suggestive of ileocaecal Crohn's disease, and colonoscopy revealed a stricture at proximal transverse colon with multiple superficial ulcers. She underwent a mesentery sparing right hemicolectomy and had an uneventful recovery. The biopsy, however, was reported to be moderately differentiated adenocarcinoma stage T3N0 with a harvest of four pericolic nodes. Adjuvant chemotherapy was advised, which she deferred. Ten months later, she presented to the emergency room with features of intestinal obstruction. Contrast CT of the abdomen showed thickening at the anastomotic site with intestinal obstruction. On exploratory laparotomy, tumour recurrence was noted at the site of the anastomosis and diffuse peritoneal metastasis. A palliative diversion ileostomy was done due to inoperable obstructing disease. She was then given palliative therapy and subsequently succumbed to the illness. The inclusion of mesentery with the resected specimen in Crohn's disease has been a debate over many years. Since the preoperative diagnosis of carcinoma of the bowel in Crohn's disease is challenging, all ileocolic resections should be radical as done in oncological resections. This would yield better oncological safety and may improve survival rates., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2020. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2020
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47. Cervical sympathetic schwannoma: a forgotten differential for Horner's syndrome.
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Dsouza R, Kota AA, Agarwal S, and Issac R
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- Humans, Neck, Horner Syndrome diagnosis, Horner Syndrome etiology, Neurilemmoma diagnosis, Neurilemmoma diagnostic imaging
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- 2020
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48. Mycotic abdominal aortic aneurysm complicated by infective spondylitis due to P seudomonas aeruginosa .
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Dsouza R, Kota AA, Jain S, and Agarwal S
- Subjects
- Aged, Aneurysm, Infected therapy, Anti-Bacterial Agents therapeutic use, Aortic Aneurysm, Abdominal therapy, Humans, Male, Pseudomonas aeruginosa, Spondylitis therapy, Aneurysm, Infected microbiology, Aortic Aneurysm, Abdominal microbiology, Ceftazidime therapeutic use, Pseudomonas Infections complications, Spondylitis microbiology
- Abstract
A 67-year-old man with diabetes and hypertension presented with complaints of abdominal pain and lower back ache for 7 months, with intermittent episodes of fever. On examination, there was an expansile mass in the upper abdomen with bruit on auscultation. He also had tenderness in the L1-L2 vertebral space with paraspinal fullness, causing painful restriction of lower limb motor functions but without affecting sensation. On evaluation, he was found to have an abdominal aortic aneurysm with infective lumbar spondylodiscitis. The aspirate from the paravertebral infected tissue and cultures from blood grew Pseudomonas aeruginosa , a rare causative agent of mycotic aortic aneurysm. Whether the infective spondylitis spread to the abdominal aorta causing the mycotic aneurysm or vice versa is a dilemma in such a case. However, the mainstay of treatment remains adequate source control and repair of the aneurysm with appropriate antibiotic therapy. Our patient received intravenous antibiotics for P . aeruginosa based on sensitivity, following which he underwent debridement of the infective spondylodiscitis with aneurysmorrhaphy. He had an uneventful recovery and was well at 3-month follow-up., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2020. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2020
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49. Streptococcus constellatus : a rare causative agent of pyogenic liver abscess.
- Author
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Dsouza R, Roopavathana B, Chase S, and Nayak S
- Subjects
- Abdominal Pain etiology, Adult, Anti-Bacterial Agents therapeutic use, Combined Modality Therapy, Diagnosis, Differential, Drainage, Fever etiology, Humans, Jaundice etiology, Liver Abscess, Pyogenic complications, Liver Abscess, Pyogenic diagnostic imaging, Liver Abscess, Pyogenic therapy, Male, Streptococcal Infections complications, Streptococcal Infections diagnostic imaging, Streptococcal Infections therapy, Tomography, X-Ray Computed, Liver Abscess, Pyogenic diagnosis, Streptococcal Infections diagnosis, Streptococcus constellatus isolation & purification
- Abstract
A 26-year-old man who was previously well presented to the emergency in septic shock. He had a preceding history of fever, right upper abdominal pain and jaundice. On examination, there was tenderness over the right hypochondrium and epigastrium, without features of generalised peritonitis. His blood tests were suggestive of sepsis with deranged liver function tests. CT scan of the abdomen showed multiples abscesses in various segments of the liver and a thrombus in the inferior venacava, without any other intraabdominal focus of infection. The abscess was aspirated under sonographic guidance, and the cultures grew Streptococcus constellatus species of S. milleri group (SMG). He received crystalline penicillin, based on culture sensitivity and underwent drainage of the abscess. There was a clinical improvement and he was subsequently discharged in a stable condition. On 3 months follow-up, there was a complete resolution of the liver abscess and normalisation of the liver function tests., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2019. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2019
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50. Promoting oral health in nursing education through interprofessional collaborative practice: A quasi-experimental survey study design.
- Author
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Dsouza R, Quinonez R, Hubbell S, and Brame J
- Subjects
- Attitude of Health Personnel, Education, Nursing methods, Humans, North Carolina, Surveys and Questionnaires, Interprofessional Relations, Oral Health education, Students, Nursing psychology
- Abstract
Background: Optimal oral health education is limited in nursing curricula and may therefore, not translate as a priority for nurses in clinical practice., Objectives: To evaluate the influence of an educational intervention on knowledge, confidence, practice behaviors, and perceived barriers of nursing students regarding preventive oral health services., Design: Quasi-experimental pre-post survey study design., Participants: Sixty-four first-year Accelerated Bachelor of Nursing (ASBN) students at the University of North Carolina at Chapel Hill., Methods: Students were asked to complete oral-health-related questionnaires following didactic and clinical simulation on principles of oral health, oral screening, counseling, and referral to a dentist. A post-survey following clinical rotations was completed testing long-term effectiveness., Results: Fifty-five (86%) ABSN students completed the pre-survey, 49 (77%) completed the post-survey; 44 (69%) completed both. Participants' showed a significant increase in knowledge from pre-post questionnaires for two of five questions (p = 0.04; p < 0.0001). Confidence scores in performing oral screenings (p < 0.0001) and counseling (p = 0.006) increased; while scores regarding referrals decreased (p = 0.718). Post-intervention, 37% reported performing oral screenings, 45% counseling, and 8% dental referrals. Respondents reported a significant increase in willingness to implement oral health services during clinical visits (p < 0.0001)., Conclusion: Mixed educational methods can successfully influence oral health knowledge and confidence among ABSN students and their willingness to perform in clinical practice., (Published by Elsevier Ltd.)
- Published
- 2019
- Full Text
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