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1.
Nat Mater ; 22(9): 1136-1143, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37537353

RESUMEN

The development of solid-state Li-metal batteries has been limited by the Li-metal plating and stripping rates and the tendency for dendrite shorts to form at commercially relevant current densities. To address this, we developed a single-phase mixed ion- and electron-conducting (MIEC) garnet with comparable Li-ion and electronic conductivities. We demonstrate that in a trilayer architecture with a porous MIEC framework supporting a thin, dense, garnet electrolyte, the critical current density can be increased to a previously unheard of 100 mA cm-2, with no dendrite-shorting. Additionally, we demonstrate that symmetric Li cells can be continuously cycled at a current density of 60 mA cm-2 with a maximum per-cycle Li plating and stripping capacity of 30 mAh cm-2, which is 6× the capacity of state-of-the-art cathodes. Moreover, a cumulative Li plating capacity of 18.5 Ah cm-2 was achieved with the MIEC/electrolyte/MIEC architecture, which if paired with a state-of-the-art cathode areal capacity of 5 mAh cm-2 would yield a projected 3,700 cycles, significantly surpassing requirements for commercial electric vehicle battery lifetimes.

2.
Faraday Discuss ; 248(0): 266-276, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-37753630

RESUMEN

The full electrification of transportation will require batteries with both 3-5× higher energy densities and a lower cost than what is available in the market today. Energy densities of >1000 W h kg-1 will enable electrification of air transport and are among the very few technologies capable of achieving this energy density. Limetal-O2 or Limetal-air are theoretically able to achieve this energy density and are also capable of reducing the cost of batteries by replacing expensive supply chain constrained cathode materials with "free" air. However, the utilization of liquid electrolytes in the Limetal-O2/Limetal-air battery has presented many obstacles to the optimum performance of this battery including oxidation of the liquid electrolyte and the Limetal anode. In this paper a path towards the development of a Limetal-air battery using a cubic garnet Li7La3Zr2O12 (LLZ) solid-state ceramic electrolyte in a 3D architecture is described including initial cycling results of a Limetal-O2 battery using a recently developed mixed ionic and electronic (MIEC) LLZ in that 3D architecture. This 3D architecture with porous MIEC structures for the O2/air cathode is essentially the same as a solid oxide fuel cell (SOFC) indicating the importance of leveraging SOFC technology in the development of solid-state Limetal-O2/air batteries.

3.
Eur J Dent Educ ; 24(2): 282-291, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31925893

RESUMEN

OBJECTIVE: To ascertain dental educators' attitudes towards the teaching of dental amalgam at dental schools in Australia and identify preferred curricular approaches in a potentially "amalgamless" profession. METHODS: A mixed methods analysis was employed based on an open-ended response survey followed by a closed-ended questionnaire. Identification of key issues from the survey helped frame the questionnaire. Participants included those with expertise in operative and restorative dentistry, with direct involvement in curriculum development or delivery, at Australian dental schools. RESULTS: Participants numbered fifteen and represented seven of the nine dental schools in Australia. Key themes identified and explored included the following: (in)consistency of approach to teaching restorative dentistry; a perceived disconnect between undergraduate study and the "real world"; a need for a focus on teaching of alternatives to dental amalgam (80 per cent (strongly) agreeing); the contradictory nature of the evidence base and literature that is not readily understood; the need for more post-graduate education relating to adhesive restorative materials (86 per cent (strongly) agreeing); the need for dental amalgam to continue to be available; formal understandings (guidelines) as to the use of dental amalgam; dental schools in Australia being heard on these issues; and the relevance of this issue (100 per cent (strongly) agreeing the issue is topical and important). CONCLUSION: There is a broad consensus of dental educators at Australian dental schools as how best to approach the teaching of amalgam if a phase-down is to occur and the issues any such approach may face.


Asunto(s)
Amalgama Dental , Restauración Dental Permanente , Actitud , Australia , Resinas Compuestas , Curriculum , Educación en Odontología , Encuestas y Cuestionarios , Enseñanza
4.
Phys Chem Chem Phys ; 17(3): 2199-209, 2015 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-25483273

RESUMEN

Since the discovery of their excellent performance as the light-absorbing semiconducting component in photovoltaic cells, the PbX3CH3NH3 (X = I, Br, Cl) perovskites have received renewed attention. The five polymorphs stable above 200 K - the tetragonal phases for X = I, Br, Cl and the cubic phases for X = I, Br - were studied using periodic DFT calculations involving hybrid functionals (PBE0 and HSE), employing Gaussian-type orbitals as well as plane waves and including relativistic effects (spin-orbit coupling). The influence of the halogen substitution and of the crystal phase on these properties is analysed by comparing the properties obtained in this study to the experimental ones and to the theoretical ones computed using other methods. We show that an accurate treatment of these systems requires the description of dispersion forces and spin-orbit coupling. The different time scales for the electronic and vibrational components of the polarizability inspire the hypothesis that several interfacial charge transfer mechanisms are encountered in the working principle of the photovoltaic devices involving these perovskite materials. The heavy elements in the structure (Pb, I) play a major role in the high polarizability and the low effective charge carrier masses and hence in the low exciton binding energies and the high charge mobility. This systematic work on the PbX3CH3NH3 family offers to theoreticians an overview of the landscape of quantum chemical methods to enable a reasonable choice of methodology for studying these systems.

5.
Indian J Crit Care Med ; 19(8): 487-9, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26321811

RESUMEN

Hypertriglyceridemia can cause severe diseases such as acute pancreatitis (AP) and coronary artery disease. The routine management of hypertriglyceridemia is dietary restriction of fat and lipid-lowering medications to manage the secondary or precipitating causes of hypertriglyceridemia. However, in cases of AP with severe hypertriglyceridemia (SHTG) (triglycerides [TG] >1000 mg/dl) rapid reduction of TG levels to well below 1000 mg/dl can improve outcome and prevent further episodes of pancreatitis. Plasmapheresis is a therapeutic option in such medical emergencies. We discussed 2 cases of severe AP with SHTG where we used early plsmapheresis along with other supportive management.

6.
BMJ Open Ophthalmol ; 9(1)2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38272533

RESUMEN

OBJECTIVE: To evaluate the Descemet membrane endothelial keratoplasty (DMEK) preparation performance of trainee surgeons in an ex vivo human donor cornea DMEK wet lab simulation setting. METHODS: Human donor corneoscleral rims unsuitable for transplantation were obtained from Moorfields Lions Eye Bank. At the wet lab, graft stripping was performed by scoring the peripheral endothelium. The trypan blue positive cells (TBPC) and cell density (cells/mm2-reticule count) were counted manually before and after stripping. The procedural time, peripheral and central tears and complete peel-off were also recorded and analysed. RESULTS: Eight trainee surgeons attended the wet lab each attempting three DMEKs. Between the first and last attempts a significant decrease was seen in the procedural time (17.6 min vs 10.6 min (p<0.05)) and the TBPC % (12.9% vs 3.8% (p<0.05)). The percentage of tears peripherally and centrally also reduced between the first and the last trials (50% vs 13% (p=0.2226) and 38% vs 0% (p=0.1327)). A significant correlation was found between longer peeling times and higher TBPC % (p<0.001) with a 0.7% endothelial mortality increase for each additional minute required to complete the peel. CONCLUSIONS: DMEK wet labs provide a controlled risk-free learning opportunity for trainee surgeons to improve confidence and competence. Wet labs improve the success rate of DMEK graft preparation as well as flatten the learning curve. This emphasises the importance of continued support for the expansion of this valuable learning resource, promoting wider uptake of DMEK surgery.


Asunto(s)
Queratoplastia Endotelial de la Lámina Limitante Posterior , Humanos , Córnea/cirugía , Bancos de Ojos , Donantes de Tejidos , Curva de Aprendizaje , Azul de Tripano
7.
ACS Appl Mater Interfaces ; 15(1): 751-760, 2023 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-36580372

RESUMEN

Lithium garnet Li7La3Zr2O12 (LLZO), with high ionic conductivity and chemical stability against a Li metal anode, is considered one of the most promising solid electrolytes for lithium-sulfur batteries. However, an infinite charge time resulting in low capacity has been observed in Li-S cells using Ta-doped LLZO (Ta-LLZO) as a solid electrolyte. It was observed that this cell failure is correlated with lanthanum segregation to the surface of Ta-LLZO that reacts with a sulfur cathode. We demonstrated this correlation by using lanthanum excess and lanthanum deficient Ta-LLZO as the solid electrolyte in Li-S cells. To resolve this challenge, we physically separated the sulfur cathode and LLZO using a poly(ethylene oxide) (PEO)-based buffer interlayer. With a thin bilayer of LLZO and the stabilized sulfur cathode/LLZO interface, the hybridized Li-S batteries achieved a high initial discharge capacity of 1307 mA h/g corresponding to an energy density of 639 W h/L and 134 W h/kg under a high current density of 0.2 mA/cm2 at room temperature without any indication of a polysulfide shuttle. By simply reducing the LLZO dense layer thickness to 10 µm as we have demonstrated before, a significantly higher energy density of 1308 W h/L and 257 W h/kg is achievable. X-ray diffraction and X-ray photoelectron spectroscopy indicate that the PEO-based interlayer, which physically separates the sulfur cathode and LLZO, is both chemically and electrochemically stable with LLZO. In addition, the PEO-based interlayer can adapt to the stress/strain associated with sulfur volume expansion during lithiation.

8.
JMIR Med Inform ; 10(4): e29385, 2022 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-35404254

RESUMEN

BACKGROUND: Obtaining patient feedback is an essential mechanism for health care service providers to assess their quality and effectiveness. Unlike assessments of clinical outcomes, feedback from patients offers insights into their lived experiences. The Department of Health and Social Care in England via National Health Service Digital operates a patient feedback web service through which patients can leave feedback of their experiences in structured and free-text report forms. Free-text feedback, compared with structured questionnaires, may be less biased by the feedback collector and, thus, more representative; however, it is harder to analyze in large quantities and challenging to derive meaningful, quantitative outcomes. OBJECTIVE: The aim of this study is to build a novel data analysis and interactive visualization pipeline accessible through an interactive web application to facilitate the interrogation of and provide unique insights into National Health Service patient feedback. METHODS: This study details the development of a text analysis tool that uses contemporary natural language processing and machine learning models to analyze free-text clinical service reviews to develop a robust classification model and interactive visualization web application. The methodology is based on the design science research paradigm and was conducted in three iterations: a sentiment analysis of the patient feedback corpus in the first iteration, topic modeling (unigram and bigram)-based analysis for topic identification in the second iteration, and nested topic modeling in the third iteration that combines sentiment analysis and topic modeling methods. An interactive data visualization web application for use by the general public was then created, presenting the data on a geographic representation of the country, making it easily accessible. RESULTS: Of the 11,103 possible clinical services that could be reviewed across England, 2030 (18.28%) different services received a combined total of 51,845 reviews between October 1, 2017, and September 30, 2019. Dominant topics were identified for the entire corpus followed by negative- and positive-sentiment topics in turn. Reviews containing high- and low-sentiment topics occurred more frequently than reviews containing less polarized topics. Time-series analysis identified trends in topic and sentiment occurrence frequency across the study period. CONCLUSIONS: Using contemporary natural language processing techniques, unstructured text data were effectively characterized for further analysis and visualization. An efficient pipeline was successfully combined with a web application, making automated analysis and dissemination of large volumes of information accessible. This study represents a significant step in efforts to generate and visualize useful, actionable, and unique information from free-text patient reviews.

9.
JACC Clin Electrophysiol ; 8(9): 1122-1132, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36137717

RESUMEN

BACKGROUND: The role of cardiac magnetic resonance (CMR) in the evaluation and management of patients with frequent premature ventricular complexes (PVCs) of unknown etiology remains unclear. OBJECTIVES: This study evaluated the prevalence and prognostic significance of myocardial abnormalities detected with CMR among patients with frequent PVCs and no known structural heart disease. METHODS: This prospective cohort study included consecutive patients with frequent PVCs and a negative initial diagnostic work-up who underwent CMR with late gadolinium enhancement imaging. The clinical outcome was a composite of mortality, ventricular fibrillation, sustained ventricular tachycardia, or reduction in left ventricular ejection fraction of ≥10%. RESULTS: A total of 255 patients were included, of whom 35 (13.7%) had evidence of myocardial abnormality on CMR. Age ≥60 years (odds ratio [OR]: 6.96; 95% CI: 1.30-37.18), multifocal PVCs (OR: 10.90; 95% CI: 3.21-36.97), and non-outflow tract left ventricular PVC origin (OR: 3.00; 95% CI: 1.00-8.95) were independently associated with the presence of a myocardial abnormality on CMR. After a median follow-up of 36 months, the composite outcome occurred in 15 (5.9%) patients. The presence of a myocardial abnormality on CMR was independently associated with the composite outcome (HR: 4.35; 95% CI: 1.34-14.15; P = 0.014). CONCLUSIONS: One in 7 patients with frequent PVCs with no known structural heart disease had myocardial abnormality detected on CMR, and these abnormalities were associated with adverse clinical outcomes. These findings highlight the important role of CMR in the evaluation of patients with frequent PVCs.


Asunto(s)
Función Ventricular Izquierda , Complejos Prematuros Ventriculares , Humanos , Persona de Mediana Edad , Medios de Contraste , Gadolinio , Espectroscopía de Resonancia Magnética , Estudios Prospectivos , Volumen Sistólico , Complejos Prematuros Ventriculares/diagnóstico
10.
World J Hepatol ; 13(5): 522-532, 2021 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-34131467

RESUMEN

The coronavirus disease 2019 (COVID-19) pandemic has caused unprecedented pressure on public health and healthcare. The pandemic surge and resultant lockdown have affected the standard-of-care of many medical conditions and diseases. The initial uncertainty and fear of cross transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have changed the routine management of patients with pre-existing liver diseases, hepatocellular carcinoma, and patients either listed for or received a liver transplant. COVID-19 is best described as a multisystem disease caused by SARS-CoV-2, and it can cause acute liver injury or decompensation of the pre-existing liver disease. There has been considerable research on the pathophysiology, infection transmission, and treatment of COVID-19 in the last few months. The pathogenesis of liver involvement in COVID-19 includes viral cytotoxicity, the secondary effect of immune dysregulation, hypoxia resulting from respiratory failure, ischemic damage caused by vascular endotheliitis, congestion because of right heart failure, or drug-induced liver injury. Patients with chronic liver diseases, cirrhosis, and hepatocellular carcinoma are at high risk for severe COVID-19 and mortality. The phase III trials of recently approved vaccines for SARS-CoV-2 did not include enough patients with pre-existing liver diseases and excluded immunocompromised patients or those on immunomodulators. This article reviews the currently published research on the effect of COVID-19 on the liver and the management of patients with pre-existing liver disease, including SARS-CoV-2 vaccines.

11.
Trop Gastroenterol ; 31(3): 155-64, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21560518

RESUMEN

INTRODUCTION: Endoscopic glue (N-butyl-2-cyanoacrylate) injection has emerged as promising therapy for bleeding gastric varices (GV). We evaluated safety and long term efficacy of this technique in patients with portal hypertension and large bleeding GV. PATIENT AND METHODS: 170 patients (mean age 40.9 +/- 14y; 132 male; 142 had cirrhosis, 40 Child A, 62 Child B, 40 Child C) underwent glue injection into GV (F3 140, F2 30; fundal 114) as emergency procedure for active bleeding in 62 and electively for prevention of rebleeding in 108. Glue was injected intra-variceally under endoscopic vision, 0.5-4 ml/aliquot, repeated at 3 weeks till varices were eradicated/solidified. The efficacy was assessed by hemostasis at 48 h, primary, secondary, definitive success and treatment failure. RESULTS: The overall hemostasis rate at 48h was 82.3% (51/62). Follow up was available in 158 patients for mean of 30.7 + 17.2 months. Repeat injections were performed in 76. The mean number of injections were 1.9 +/- 1.0 (1-4); total volume was 2.5 +/- 1.7 ml/patient. The status of GVs at last follow up was: disappeared in 32 (22.6%); F1 solidified in 46 (32.3%); F2 solidified in 64 (45.0%). Bleeding recurred in 14.5% (23/158); 60% within 2 weeks of injection. The primary, secondary and definitive success rates were 85.4% (135/158), 4.4% (7/158) and 89.9% (142/158) respectively and treatment failure rate was 10% (16/158). No significant complications were noticed except for injection site ulceration in 32. Twenty patients died on follow up (9 died of uncontrolled bleeding, 11 died of liver failure). CONCLUSION: Endoscopic glue injection into bleeding GVs was effective in achieving hemostasis in 82% with a definitive success rate of 90% and had a good safety profile on long-term follow up.


Asunto(s)
Enbucrilato/administración & dosificación , Várices Esofágicas y Gástricas/terapia , Hemorragia Gastrointestinal/terapia , Adhesivos Tisulares/administración & dosificación , Adolescente , Adulto , Anciano , Enbucrilato/efectos adversos , Femenino , Hemorragia Gastrointestinal/prevención & control , Gastroscopía , Hemostasis Endoscópica/efectos adversos , Humanos , Inyecciones/métodos , Masculino , Persona de Mediana Edad , Factores de Tiempo , Adhesivos Tisulares/efectos adversos , Adulto Joven
12.
Heart ; 105(18): 1408-1413, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31142596

RESUMEN

OBJECTIVE: The natural history of frequent premature ventricular complexes (PVCs) in association with preserved left ventricular ejection fraction (LVEF) is uncertain. The optimal management of this population is thus undefined. We studied the outcomes of untreated patients with frequent PVCs and preserved LVEF. METHODS: This cohort study prospectively evaluated consecutive patients from 2012 to 2017, with asymptomatic or minimally symptomatic frequent idiopathic PVCs (≥5% PVCs in 24 hours; normal LVEF; no cause identified on comprehensive evaluation). No suppressive therapy (ablation or antiarrhythmic drugs) were used and patients were followed with serial ambulatory ECG monitoring and echocardiography. The primary arrhythmic outcome was reduction in PVC burden to <1% on serial ambulatory monitoring. The primary echocardiographic outcome was a reduction of LVEF to <50%. RESULTS: One hundred patients met inclusion criteria (mean age 51.8 years, 57% female) with a median PVC burden of 18.4%. Reduction to <1% PVCs occurred in 44 of 100 patients (44.0%) at a median of 15.4 months (range 2.6 to 64.3). Recurrence was uncommon (4/44, 9.1%). Four patients (4.3%) with a persistently elevated PVC burden developed left ventricular dysfunction (LVEF <50%) during the follow-up period at a range of 53-71 months. The initial PVC burden did not predict subsequent resolution (HR 1.00(0.97, 1.03); p=0.86). CONCLUSIONS: A strategy of active surveillance is appropriate for the majority of patients with frequent idiopathic PVCs in association with preserved LVEF, owing to the low risk of developing left ventricular systolic dysfunction and the high rate of spontaneous resolution.


Asunto(s)
Frecuencia Cardíaca , Volumen Sistólico , Función Ventricular Izquierda , Complejos Prematuros Ventriculares/fisiopatología , Adolescente , Adulto , Anciano , Enfermedades Asintomáticas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Recurrencia , Sistema de Registros , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Disfunción Ventricular Izquierda/etiología , Disfunción Ventricular Izquierda/fisiopatología , Complejos Prematuros Ventriculares/complicaciones , Complejos Prematuros Ventriculares/diagnóstico , Adulto Joven
13.
Indian J Plast Surg ; 45(3): 585-6, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23450934
14.
Indian J Gastroenterol ; 36(5): 390-399, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29034439

RESUMEN

BACKGROUND: Though pathogenesis of non-alcoholic steatohepatitis (NASH) is unclear, association with small intestinal bacterial overgrowth [SIBO] and fecal dysbiosis is suggested. We evaluated SIBO in NASH using quantitative jejunal aspirate culture (conventional criteria: ≥ 105 colony forming unit (CFU)/mL and newer cutoff ≥ 103 CFU/mL) and glucose hydrogen breath test. METHODS: Thirty-eight patients with NASH (age 37.5 years, range 20-54, 9, 24% female), diagnosed by ultrasonography, alanine aminotransferase >1.5 times normal and liver biopsy (in 27/38, 71%) and exclusion of other causes and 12 constipation-predominant irritable bowel syndrome as historical controls (age 39.5-y, 26-44; 3, 25% female) without fatty liver were studied. RESULTS: Jejunal aspirates, obtained in 35/38 patients, were sterile in 14/35 (40%) and bacteria isolated in 21 (60%) (all aerobic, in one anaerobe also; Gram positive 5, negative 13, both 3). In contrast, bacteria (two Gram negative) were isolated in 3/12 (25%) controls (odds ratio 4.5, 95% CI 1.0-19.5; p = 0.04); colony counts were higher in NASH than controls (median 380 CFU/mL, 0-200,000 vs. 0 CFU/mL, 0-1000; p = 0.02). Gram negative bacteria tended to be commoner in NASH than controls (16/35 vs. 2/12; p = 0.07). Seven out of 35 (20%) patients with NASH (≥ 105 CFU/mL in 5 and 2 other on glucose hydrogen breath test) and no control had SIBO (p = ns); low-grade SIBO (≥103 CFU/mL) was commoner in NASH than controls (14/35, 40%, vs. 1/12, 8.3%; p = 0.04). There was no correlation between bacterial colony count and bacterial type and anthropometric and biochemical parameters. CONCLUSION: Low-grade bacterial overgrowth, particularly with Gram negative bacteria, was commoner in NASH than controls.


Asunto(s)
Infecciones Bacterianas , Carga Bacteriana , Colitis/etiología , Colitis/microbiología , Microbioma Gastrointestinal , Bacterias Gramnegativas/aislamiento & purificación , Yeyuno/microbiología , Enfermedad del Hígado Graso no Alcohólico/microbiología , Adulto , Pruebas Respiratorias , Colitis/diagnóstico , Femenino , Glucosa , Humanos , Hidrógeno , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Adulto Joven
15.
Free Radic Biol Med ; 41(6): 979-84, 2006 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-16934681

RESUMEN

Oxidative stress markers and functional tests were studied to confirm early biochemical and functional changes in retina and hippocampus of diabetic mice. The effects of lutein treatment were also tested. Mice were induced diabetic by alloxan injection and divided into subgroups: control, control+lutein, diabetic, diabetic+lutein, diabetic+insulin, and diabetic+insulin+lutein. Treatments started on Day 4 after alloxan injection and animals were sacrificed on Day 14. Malondialdehyde and glutathione concentrations and glutathione peroxidase activity were measured as oxidative stress markers. The following functional tests for retina and hippocampus were performed: electroretinogram and Morris water maze test. NFkappaB activity was also measured. Oxidative stress and NFkappaB activity increase in the retina and hippocampus after 15 days of diabetes. Impairment of the electroretinogram and a correlation between latencies of the water maze test and glycated hemoglobin (HbA1c) levels were observed. Lutein prevented all these changes even under hyperglycemic conditions. Retina appears to be affected earlier than hippocampus by diabetes-induced oxidative stress. Although a proper glycemic control is desirable in preventing the development of diabetic complications, it is not sufficient to prevent them completely. Lutein could be an appropriate coadjuvant treatment for the changes observed in this study.


Asunto(s)
Diabetes Mellitus Experimental/fisiopatología , Hipocampo/fisiopatología , Luteína/farmacología , Retina/fisiopatología , Animales , Glucemia/metabolismo , Electrorretinografía , Glutatión/metabolismo , Hipocampo/efectos de los fármacos , Masculino , Malondialdehído/metabolismo , Aprendizaje por Laberinto/efectos de los fármacos , Ratones , FN-kappa B/metabolismo , Valores de Referencia , Retina/efectos de los fármacos
16.
PLoS One ; 11(2): e0146837, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26889676

RESUMEN

BACKGROUND: Dealing with insistent patient demand for antibiotics is an all too common part of a General Practitioner's daily routine. This study explores the extent to which portable Immersive Virtual Reality technology can help us gain an accurate understanding of the factors that influence a doctor's response to the ethical challenge underlying such tenacious requests for antibiotics (given the threat posed by growing anti-bacterial resistance worldwide). It also considers the potential of such technology to train doctors to face such dilemmas. EXPERIMENT: Twelve experienced GPs and nine trainees were confronted with an increasingly angry demand by a woman to prescribe antibiotics to her mother in the face of inconclusive evidence that such antibiotic prescription is necessary. The daughter and mother were virtual characters displayed in immersive virtual reality. The specific purposes of the study were twofold: first, whether experienced GPs would be more resistant to patient demands than the trainees, and second, to investigate whether medical doctors would take the virtual situation seriously. RESULTS: Eight out of the 9 trainees prescribed the antibiotics, whereas 7 out of the 12 GPs did so. On the basis of a Bayesian analysis, these results yield reasonable statistical evidence in favor of the notion that experienced GPs are more likely to withstand the pressure to prescribe antibiotics than trainee doctors, thus answering our first question positively. As for the second question, a post experience questionnaire assessing the participants' level of presence (together with participants' feedback and body language) suggested that overall participants did tend towards the illusion of being in the consultation room depicted in the virtual reality and that the virtual consultation taking place was really happening.


Asunto(s)
Ética Médica/educación , Médicos Generales/ética , Relaciones Médico-Paciente/ética , Pautas de la Práctica en Medicina/ética , Terapia de Exposición Mediante Realidad Virtual/educación , Adulto , Antibacterianos/uso terapéutico , Teorema de Bayes , Femenino , Médicos Generales/psicología , Humanos , Masculino , Persona de Mediana Edad , Pautas de la Práctica en Medicina/estadística & datos numéricos , Derivación y Consulta/ética , Entrenamiento Simulado/métodos , Encuestas y Cuestionarios
17.
FASEB J ; 18(11): 1255-7, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15180954

RESUMEN

Our study aimed to investigate, in vivo, the relationship between vitamin A status and NF-kappaB activity, a transcription factor central in regulating inflammatory and immune responses. We used a novel transgenic murine NF-kappaB-luciferase reporter model that enabled molecular imaging of NF-kappaB activity in live mice via an intensified image-capture apparatus. Whole-body luminescence, which reflects overall NF-kappaB activity, was elevated 2.2-fold in vitamin A-deficient (VAD) mice compared with control mice. Specifically, NF-kappaB activity in VAD mice was increased 1.8-fold in the lymph nodes and 1.4-fold in the thymus and, NF-kappaB induction in UVB radiation-exposed skin was also enhanced in VAD mice compared with control mice. The administration of all-trans retinoic acid to VAD mice resulted in a transient reduction in NF-kappaB activity and, conversely, a single dose of the RAR-pan-antagonist, AGN 194310, administered to control mice, led to a marked, transient induction of whole-body luminescence. Our results suggest that vitamin A status, and vitamin A itself, affects NF-kappaB activity in vivo and that the elevated NF-kappaB activity in VAD may be a mechanism underlying some of the features of VAD syndrome.


Asunto(s)
FN-kappa B/metabolismo , Deficiencia de Vitamina A/metabolismo , Animales , Benzoatos/farmacología , Genes Reporteros , Cadenas kappa de Inmunoglobulina/genética , Luciferasas/genética , Tejido Linfoide/metabolismo , Ratones , Ratones Transgénicos , Piel/metabolismo , Piel/efectos de la radiación , Linfocitos T/metabolismo , Tiofenos/farmacología , Activación Transcripcional/efectos de los fármacos , Activación Transcripcional/efectos de la radiación , Tretinoina/antagonistas & inhibidores , Tretinoina/farmacología , Tretinoina/uso terapéutico , Rayos Ultravioleta , Deficiencia de Vitamina A/tratamiento farmacológico , Deficiencia de Vitamina A/genética
18.
BMC Gastroenterol ; 5: 27, 2005 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-16098234

RESUMEN

BACKGROUND: Autoimmune hepatitis (AIH) has been reported to show considerable geographical variation in frequency and clinical manifestations. It is considered a rare cause of liver disease in India. The present study was undertaken to determine the incidence, clinical, biochemical and histological profile of AIH in this part of the world. METHODS: Patients presenting with acute or chronic liver disease between January 1999 and June 2002 were evaluated prospectively. AIH was diagnosed using the international autoimmune hepatitis group criteria. Workup included clinical, biochemical, USG, viral markers, UGI endoscopy, AI markers (ANA, SMA, Anti-LKM, AMA, RF, p-ANCA) using indirect immunofluorescence and liver biopsy if possible. RESULTS: Forty-one of 2401 (1.70%) patients were diagnosed to have autoimmune liver disease. Out of these, 38 had autoimmune hepatitis and the rest 3 had primary biliary cirrhosis. The mean age of the patients of autoimmune hepatitis was 36.2 (15.9) years, 34 (89.4%) were females, and the duration of symptoms was 20.3 (20.5) months. Nineteen (50%) of them presented with chronic hepatitis, 13 (34.2%) as cirrhosis, 5 (13.1%) with acute hepatitis and 1 (2.6%) with cholestatic hepatitis. The presentations were jaundice in 21 (55.2%), pedal edema and hepatomegaly in 17 (44.7%), splenomegaly in 13 (34.2%), encephalopathy, abdominal pain in 9 (23.6%) and fever in 8 (21%). Twelve had esophageal varices and 3 had bled. Biochemical parameters were ALT 187 (360) U/L, AST 157 (193) U/L, ALP 246 (254) U/L, globulin 4.1 (1.6) g/dL, albumin 2.8 (0.9) g/dL, bilirubin 5.2 (7.4) mg/dL, prothrombin time 17 (7) sec and ESR 47 (17) sec. The autoimmune markers were SMA (24), ANA (15), both SMA and ANA (4), AMA (1), rheumatoid factor (2), pANCA (1), and Anti-LKM in none. Thirty (79%) patients had definite AIH and eight (21%) had probable AI hepatitis. Associated autoimmune diseases was seen in 15/38 (39.4%), diabetes 4, hypothyroidism 3, vitiligo 2, thrombocytopenia 2, rheumatoid arthritis 2, Sjogren's syndrome 1 and autoimmune polyglandular syndrome III in 1. Viral markers were positive in two patients, one presenting as acute hepatitis and HEV-IgM positive and another anti-HCV positive. CONCLUSION: In India, autoimmune hepatitis is uncommon and usually presents with chronic hepatitis or cirrhosis, acute hepatitis being less common. Age at presentation was earlier but clinical parameters and associated autoimmune diseases were similar to that reported from the west. Primary biliary cirrhosis is rare. Type II AIH was not observed.


Asunto(s)
Hepatitis Autoinmune/epidemiología , Hepatitis Autoinmune/fisiopatología , Hígado/patología , Adolescente , Adulto , Anciano , Anticuerpos/sangre , Anticuerpos Antivirales/sangre , Azatioprina/uso terapéutico , Niño , Preescolar , Endoscopía Gastrointestinal , Femenino , Glucocorticoides/uso terapéutico , Virus de Hepatitis/inmunología , Hepatitis Autoinmune/patología , Hepatitis Autoinmune/virología , Humanos , Inmunosupresores/uso terapéutico , Incidencia , India/epidemiología , Hígado/enzimología , Hígado/virología , Masculino , Persona de Mediana Edad , Prednisolona/uso terapéutico , Estudios Prospectivos , Tracto Gastrointestinal Superior/patología
19.
BMC Gastroenterol ; 5: 29, 2005 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-16164746

RESUMEN

BACKGROUND: The use of Lamivudine in chronic hepatitis B (CHB) is well known, however the reported rate of HBeAg sero-conversion and its durability post-treatment have varied considerably. We undertook the present study to study the effect of Lamivudine on HBeAg loss and seroconversion rates in Indian patients of CHB in relation to frequency, predictors and durability. METHODS: We treated 60 patients of e antigen positive CHB (with active viral replication and ongoing necro-inflammatory activity) with Lamivudine. They were followed up by monthly aminotransferases, and 3 monthly HBeAg and anti-HBe. Those who attained HBeAg sero-conversion were advised to discontinue Lamivudine after 6 months and followed up every 3 months thereafter, to see for relapse. Treatment was given for maximum of 3 years if not sero-converted. RESULTS: The annual incremental loss of HBeAg in patients receiving Lamivudine was 25 (41.6%) at end of 1st year, 33 (55%) at 2nd year and 35 (58.3%) at 3rd year. The corresponding rates for full sero-conversion were 17/60 (28.6%), 22/60 (36.6%) and 24/60 (40%) in the 3 years. HBeAg loss correlated with increased pre-therapy ALT levels (p = 0.002) and decreased pretreatment HBV-DNA levels (p = 0.004). The presence of cirrhosis had no influence on the rate of HBeAg loss. Relapse occurred in 35% (7/20) post-treatment at median time of 6 months. CONCLUSION: Indian patients showed a higher rate of HBeAg sero-conversion in the first year of Lamivudine treatment. This correlated with baseline ALT and inversely with HBV-DNA levels. Relapse rate after treatment was high and occurred soon after stopping treatment.


Asunto(s)
Antígenos e de la Hepatitis B/sangre , Hepatitis B Crónica/tratamiento farmacológico , Hepatitis B Crónica/inmunología , Lamivudine/uso terapéutico , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alanina Transaminasa/sangre , Niño , Preescolar , ADN Viral/sangre , Femenino , Estudios de Seguimiento , Virus de la Hepatitis B/genética , Hepatitis B Crónica/enzimología , Hepatitis B Crónica/epidemiología , Humanos , Incidencia , India , Masculino , Persona de Mediana Edad , Recurrencia
20.
Pain ; 101(1-2): 129-38, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12507707

RESUMEN

Perioperative pain is still a major problem, and new pharmacological means should be explored to mitigate such pain. Adenosine is an ubiquitous endogenous substance; when exogenously administered, it provides a number of salutary effects including neuromodulation, antinociception, and cytoprotective actions. The aim of this study was to characterize the perioperative antinociceptive-analgesic effects of intraoperative adenosine infusion and determine the duration of actions in the postoperative period, and compare them to those of remifentanil in patients undergoing major surgical procedures in a double-blind study.Sixty-two patients were randomly assigned to one of the two treatments. After standard induction of anesthesia, the lungs were mechanically ventilated. Anesthesia was maintained with a constant alveolar concentration of inhaled anesthetics (3% desflurane and 65% nitrous oxide in oxygen). A variable-rate of intravenous infusion of adenosine (50-500 microg kg(-1) x min(-1)) or remifentanil (0.05-0.5 microg kg(-1) x min(-1)) was initiated 5 min before the skin incision and was titrated to maintain systolic blood pressure and heart rate within 20% of baseline values during surgery. Postoperative evaluations included the level of sedation, degree of pain severity, opioid analgesic (fentanyl, morphine) consumption, and cardiorespiratory variables for 48 h. Intraoperative inhibition of the cardiovascular responses to surgical stimulation could be equally achieved by adenosine or remifentanil, and both could maintain excellent hemodynamic stability. Postoperatively, however, there were striking differences: (1). initial pain score was reduced by 60% (P<0.001) in the adenosine group compared to the remifentanil group and it remained lower throughout the 48 h recovery period; (2). postoperative morphine requirements during the first 0.25, 2 and 48 h were consistently lower in the adenosine group as compared to the remifentanil group (78, 71 and 42%, P<0.001, respectively); (3). adenosine patients remained significantly less sedated at all evaluations; (4) the end-tidal and arterial carbon dioxide values in the remifentanil group were significantly higher when patients were admitted to the postanesthesia care unit. No adverse effect of adenosine was observed at any time. Intraoperative adenosine infusion provided a salutary recovery from anesthesia associated with a pronounced and sustained postoperative pain relief. Compared to remifentanil, adenosine significantly reduced the opioid requirements and minimized the side effects including protracted sedation, cardiorespiratory instability, nausea, and vomiting in the postoperative recovery period.


Asunto(s)
Adenosina/administración & dosificación , Analgésicos Opioides/administración & dosificación , Analgésicos/administración & dosificación , Dolor Postoperatorio/tratamiento farmacológico , Piperidinas/administración & dosificación , Adenosina/efectos adversos , Adulto , Analgésicos/efectos adversos , Analgésicos Opioides/efectos adversos , Anestesia por Inhalación , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Piperidinas/efectos adversos , Remifentanilo , Resultado del Tratamiento
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