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1.
Clin Radiol ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39245603

RESUMEN

AIMS: To evaluate the ability of logistic regression and machine learning methods to predict active arterial extravasation on computed tomographic angiography (CTA) in patients with acute gastrointestinal hemorrhage using clinical variables obtained prior to image acquisition. MATERIALS AND METHODS: CT angiograms performed for the indication of gastrointestinal bleeding at a single institution were labeled retrospectively for the presence of arterial extravasation. Positive and negative cases were matched for age, gender, time period, and site using Propensity Score Matching. Clinical variables were collected including recent history of gastrointestinal bleeding, comorbidities, laboratory values, and vitals. Data were partitioned into training and testing datasets based on the hospital site. Logistic regression, XGBoost, Random Forest, and Support Vector Machine classifiers were trained and five-fold internal cross-validation was performed. The models were validated and evaluated with the area under the receiver operating characteristic curve. RESULTS: Two-hundred and thirty-one CTA studies with arterial gastrointestinal extravasation were 1:1 matched with 231 negative studies (N=462). After data preprocessing, 389 patients and 36 features were included in model development and analysis. Two hundred and fifty-five patients (65.6%) were selected for the training dataset. Validation was performed on the remaining 134 patients (34.4%); the area under the receiver operating characteristic curve for the logistic regression, XGBoost, Random Forest, and Support Vector Machine classifiers was 0.82, 0.68, 0.54, and 0.78, respectively. CONCLUSION: Logistic regression and machine learning models can accurately predict presence of active arterial extravasation on CTA in patients with acute gastrointestinal bleeding using clinical variables.

2.
Geophys Res Lett ; 49(8): e2021GL097309, 2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-35866056

RESUMEN

The mechanisms for chaos terrain formation on Europa have long been a source of debate in the scientific community. There exist numerous theoretical and numerical models for chaos formation, but to date there has been a lack of quantifiable observations that can be used to constrain models and permit comparison to the outputs of these chaos models. Here, we use mapping and statistical analysis to develop a quantitative description of chaos terrain and their observed morphologies. For nine chaos features, we map every block, or region of pre-existing terrain within disrupted matrix. We demonstrate that chaos terrains follow a continuous spectrum of morphologies between two endmembers, platy and knobby. We find that any given chaos terrain's morphology can be quantified by means of the linearized exponential slope of its cumulative block area distribution. This quantitative metric provides a new diagnostic parameter in future studies of chaos terrain formation and comparison.

3.
Am J Physiol Heart Circ Physiol ; 321(2): H339-H352, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34170194

RESUMEN

Electronic cigarettes (E-cigs) have been promoted as harm-free or less risky than smoking, even for women during pregnancy. These claims are made largely on E-cig aerosol having fewer number of toxic chemicals compared with cigarette smoke. Given that even low levels of smoking are found to produce adverse birth outcomes, we sought to test the hypothesis that vaping during pregnancy (with or without nicotine) would not be harm-free and would result in vascular dysfunction that would be evident in offspring during adolescent and/or adult life. Pregnant female Sprague Dawley rats were exposed to E-cig aerosol (1 h/day, 5 days/wk, starting on gestational day 2 until pups were weaned) using e-liquid with 0 mg/mL (E-cig0) or 18 mg/mL nicotine (E-cig18) and compared with ambient air-exposed controls. Body mass at birth and at weaning were not different between groups. Assessment of middle cerebral artery (MCA) reactivity revealed a 51%-56% reduction in endothelial-dependent dilation response to acetylcholine (ACh) for both E-cig0 and E-cig18 in 1-mo, 3-mo (adolescent), and 7-mo-old (adult) offspring (P < 0.05 compared with air, all time points). MCA responses to sodium nitroprusside (SNP) and myogenic tone were not different across groups, suggesting that endothelial-independent responses were not altered. The MCA vasoconstrictor response (5-hydroxytryptamine, 5-HT) was also not different across treatment and age groups. These data demonstrate that maternal vaping during pregnancy is not harm-free and confers significant cerebrovascular health risk/dysfunction to offspring that persists into adult life. NEW & NOTEWORTHY These data established that vaping electronic cigarettes during pregnancy, with or without nicotine, is not safe and confers significant risk potential to the cerebrovascular health of offspring in early and adult life. A key finding is that vaping without nicotine does not protect offspring from cerebrovascular dysfunction and results in the same level of cerebrovascular dysfunction (compared with maternal vaping with nicotine), indicating that the physical and/or chemical properties from the base solution (other than nicotine) are responsible for the cerebrovascular dysfunction that we observed. Listen to this article's corresponding podcast at https://ajpheart.podbean.com/e/maternal-vaping-impairs-vascular-function-in-theoffspring/.


Asunto(s)
Cigarrillo Electrónico a Vapor/farmacología , Arteria Cerebral Media/efectos de los fármacos , Nicotina/farmacología , Agonistas Nicotínicos/farmacología , Efectos Tardíos de la Exposición Prenatal , Vapeo , Vasoconstricción/efectos de los fármacos , Vasodilatación/efectos de los fármacos , Acetilcolina/farmacología , Aerosoles , Animales , Sistemas Electrónicos de Liberación de Nicotina , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/fisiopatología , Femenino , Arteria Cerebral Media/fisiopatología , Nicotina/administración & dosificación , Agonistas Nicotínicos/administración & dosificación , Nitroprusiato/farmacología , Embarazo , Ratas , Serotonina/farmacología , Vasoconstricción/fisiología , Vasoconstrictores/farmacología , Vasodilatación/fisiología , Vasodilatadores/farmacología
4.
HIV Med ; 21(5): 299-308, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31985887

RESUMEN

OBJECTIVES: The aim of the study was to assess the validity of an easy-to-calculate chronic kidney disease (CKD) risk score developed by the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) group in a longitudinal observational study of people living with HIV (PLWH) in the USA. METHODS: PLWH (2002-2016) without prior exposure to potentially nephrotoxic antiretroviral agents and with at least three estimated glomerular filtration rate (eGFR) test results were identified in the Observational Pharmaco-Epidemiology Research and Analysis (OPERA® ) cohort. Three samples were drawn independently using the same eligibility criteria but each using a different eGFR equation, specifically the Cockcroft-Gault (C-G), Modification of Diet in Renal Disease (MDRD) or Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) eGFR estimation method. Full and short D:A:D risk scores were applied. CKD was defined as a confirmed decrease in eGFR to < 60 mL/min/1.73 m2 (stages 3-5). Poisson models estimated the association between CKD incidence and a one-point increase in the continuous risk score. The incidence rate ratio (IRR), adjusted IRR (aIRR), and Harrell's discrimination statistic were used to assess validity. RESULTS: There were 19 444, 22 727 and 22 748 PLWH in the OPERA C-G, CKD-EPI and MDRD samples, respectively. The median (minimum-maximum) follow-up duration was 6.1 (0.3-9.1) years in the D:A:D cohort and ranged from 3.2 to 3.5 (0.2-15.5) years in the OPERA validation samples. The observation time for the majority of PLWH in the D:A:D cohort began prior to 2006, in stark contrast to the OPERA validation samples, where the majority of PLWH were observed after 2011. The CKD incidence ranged from 7.3 per 1000 person-years [95% confidence interval (CI) 6.8, 7.9 per 1000 person-years] in OPERA C-G to 11.0 (95% CI 10.4, 11.6 per 1000 person-years) in OPERA MDRD. In OPERA samples, IRRs by risk group and adjusted IRRs (full risk score) were similar to those in the D:A:D derivation cohort (adjusted IRR 1.3; 95% CI 1.3, 1.3). Harrell's c-statistic ranged from 0.87 to 0.92 in the OPERA samples, comparable to that in the derivation cohort (0.92). Results for short scores were similar. CONCLUSIONS: The findings support the validity of the D:A:D risk scoring method for assessing CKD (stages 3-5) probability in an exclusively USA-based sample regardless of eGFR method.


Asunto(s)
Fármacos Anti-VIH/efectos adversos , Infecciones por VIH/tratamiento farmacológico , Insuficiencia Renal Crónica/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Fármacos Anti-VIH/uso terapéutico , Femenino , Tasa de Filtración Glomerular/efectos de los fármacos , Humanos , Incidencia , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Insuficiencia Renal Crónica/inducido químicamente , Insuficiencia Renal Crónica/fisiopatología , Estados Unidos/epidemiología
5.
Nat Mater ; 17(5): 416-420, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29610487

RESUMEN

The possibility of driving phase transitions in low-density condensates through the loss of phase coherence alone has far-reaching implications for the study of quantum phases of matter. This has inspired the development of tools to control and explore the collective properties of condensate phases via phase fluctuations. Electrically gated oxide interfaces1,2, ultracold Fermi atoms3,4 and cuprate superconductors5,6, which are characterized by an intrinsically small phase stiffness, are paradigmatic examples where these tools are having a dramatic impact. Here we use light pulses shorter than the internal thermalization time to drive and probe the phase fragility of the Bi2Sr2CaCu2O8+δ cuprate superconductor, completely melting the superconducting condensate without affecting the pairing strength. The resulting ultrafast dynamics of phase fluctuations and charge excitations are captured and disentangled by time-resolved photoemission spectroscopy. This work demonstrates the dominant role of phase coherence in the superconductor-to-normal state phase transition and offers a benchmark for non-equilibrium spectroscopic investigations of the cuprate phase diagram.

6.
Phys Rev Lett ; 123(4): 042502, 2019 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-31491269

RESUMEN

We report the first measurement of the neutron cross section on argon in the energy range of 100-800 MeV. The measurement was obtained with a 4.3-h exposure of the Mini-CAPTAIN detector to the WNR/LANSCE beam at LANL. The total cross section is measured from the attenuation coefficient of the neutron flux as it traverses the liquid argon volume. A set of 2631 candidate interactions is divided in bins of the neutron kinetic energy calculated from time-of-flight measurements. These interactions are reconstructed with custom-made algorithms specifically designed for the data in a time projection chamber the size of the Mini-CAPTAIN detector. The energy averaged cross section is 0.91±0.10(stat)±0.09(syst) b. A comparison of the measured cross section is made to the GEANT4 and FLUKA event generator packages, where the energy averaged cross sections in this range are 0.60 and 0.68 b, respectively.

7.
HIV Med ; 19(10): 724-733, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30101539

RESUMEN

OBJECTIVES: The single-tablet regimen rilpivirine, emtricitabine and tenofovir alafenamide (RPV/FTC/TAF) for treatment of HIV-1-infected adults was approved based on bioequivalence. We assessed the clinical efficacy, safety and tolerability of switching to RPV/FTC/TAF from either RPV/FTC/tenofovir disoproxil fumarate (TDF) or efavirenz (EFV)/FTC/TDF. METHODS: We conducted two distinct randomized, double-blind, active-controlled, noninferiority trials in participants taking RPV/FTC/TDF (Study 1216) and EFV/FTC/TDF (Study 1160). Each study randomized virologically suppressed (HIV-1 RNA < 50 copies/mL) adults (1:1) to switch to RPV/FTC/TAF or continue their current regimen for 96 weeks. We evaluated efficacy as the proportion with HIV-1 RNA < 50 copies/mL using the Food and Drug Administration snapshot algorithm and prespecified bone and renal endpoints at week 96. RESULTS: We randomized and treated 630 participants in Study 1216 (RPV/FTC/TAF, n = 316; RPV/FTC/TDF, n = 314) and 875 in Study 1160 (RPV/FTC/TAF, n = 438; EFV/FTC/TDF, n = 437). In both studies, the efficacy of switching to RPV/FTC/TAF was noninferior to that of continuing baseline therapy at week 96, with respective percentages of patients with HIV RNA < 50 copies/mL being 89.2% versus 88.5% in Study 1216 [difference 0.7%; 95% confidence interval (CI) -4.3 to +5.8%] and 85.2% versus 85.1% in Study 1160 (difference 0%; 95% CI -4.8 to +4.8%). No participant on RPV/FTC/TAF developed treatment-emergent resistance versus two on EFV/FTC/TDF and one on RPV/FTC/TDF. Compared with continuing baseline therapy, significant improvements in bone mineral density and renal tubular markers were observed in the RPV/FTC/TAF groups (P < 0.001). CONCLUSIONS: Switching to RPV/FTC/TAF from RPV/FTC/TDF or EFV/FTC/TDF was safe and effective and improved bone mineral density and renal biomarkers up to 96 weeks with no cases of treatment-emergent resistance.


Asunto(s)
Antirretrovirales/administración & dosificación , Terapia Antirretroviral Altamente Activa/métodos , Combinación de Medicamentos , Sustitución de Medicamentos/métodos , Infecciones por VIH/tratamiento farmacológico , Adulto , Antirretrovirales/efectos adversos , Terapia Antirretroviral Altamente Activa/efectos adversos , Método Doble Ciego , Sustitución de Medicamentos/efectos adversos , Femenino , VIH-1/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , ARN Viral/sangre , Resultado del Tratamiento , Carga Viral
8.
Phys Rev Lett ; 119(5): 053201, 2017 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-28949762

RESUMEN

Slow atoms in Rydberg states can exhibit specular reflection from a cylindrical surface upon which an azimuthally periodic potential is imposed. We have constructed a concave mirror of this type, in the shape of a truncated oblate ellipsoid of revolution, which has a focal length of (1.50±0.01) m measured optically. When placed near the center of a long vacuum pipe, this structure brings a beam of n=32 positronium (Ps) atoms to a focus on a position sensitive detector at a distance of (6.03±0.03) m from the Ps source. The intensity at the focus implies an overall reflection efficiency of ∼30%. The focal spot diameter (32±1) mm full width at half maximum is independent of the atoms' flight times from 20 to 60 µs, thus indicating that the mirror is achromatic to a good approximation. Mirrors based on this principle would be of use in a variety of experiments, allowing for improved collection efficiency and tailored transport or imaging of beams of slow Rydberg atoms and molecules.

9.
J Public Health (Oxf) ; 39(4): 685-690, 2017 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-28334986

RESUMEN

Around 150 cities have emerged as notable at a global scale. With a global population of fewer than 12%, they generate 46% of world gross domestic product. There is growing interest in how cities can accelerate health improvements through wider social and economic collaboration. A team led by Public Health England in London visited counterparts in New York City and Paris to examine how city health leaders addressed public health challenges. The three cities have similar health challenges but different legal, political and fiscal resources for promoting and protecting health. Consequently, there is no single model that every city could adopt. Organizational structures, interpersonal relationships and individual skills can play an important part in effective delivery of better city health. Lack of access to published evidence on how practice has been influenced by city health policies hampers learning between cities. There is little easily comparable data to guide those interested in such learning. Municipal governments are ideally situated to join researchers to fill this gap in the literature.


Asunto(s)
Relaciones Interinstitucionales , Relaciones Interprofesionales , Gobierno Local , Administración en Salud Pública , Salud Urbana , Ciudades , Política de Salud , Promoción de la Salud/organización & administración , Humanos , Liderazgo , Londres , Ciudad de Nueva York , Paris , Salud Pública
10.
Psychol Health Med ; 22(2): 227-236, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-26872528

RESUMEN

Greater patient involvement in health decision-making requires exchange of information between the patient and the healthcare professionals. Decisions regarding healthcare at the end of life include consideration of cardiopulmonary resuscitation (CPR). The stated objectives of this study were to determine how often language around concepts of resuscitation is used in the community by examination of the English language corpora (ELC); to explore the understanding of the same language by a group of older hospital patients; and to determine the patients' knowledge of the process and success of CPR, as well as the sources of their information. Medical inpatients aged 75 years and older were surveyed to this end in the setting of a tertiary university teaching hospital. Interrogation of the Australian, British and American English Corpora was accomplished by a linguist, and a questionnaire and semi-structured interview were administered to ascertain patient knowledge. We demonstrated that although medical inpatients have some familiarity with terms relating to resuscitation, there is a lack of understanding of the context, process and outcomes of CPR. The predominant sources of information were television and print media. Examination of the ELC revealed a paucity of the use of terms related to resuscitation. This finding indicates that physicians have a duty of care to determine patients' understanding around resuscitation language, and terms used, in discussions of their preferences before assuming their engagement in shared decision-making. More open public discussion around death and resuscitation would increase the general knowledge of the population and would provide a better foundation for the discussions in times of need.


Asunto(s)
Reanimación Cardiopulmonar , Toma de Decisiones , Pacientes Internos , Lenguaje , Anciano , Anciano de 80 o más Años , Australia , Femenino , Humanos , Entrevistas como Asunto , Masculino , Participación del Paciente , Médicos , Investigación Cualitativa , Encuestas y Cuestionarios , Cuidado Terminal
11.
Phys Rev Lett ; 117(21): 216402, 2016 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-27911545

RESUMEN

The affinity A_{Ps} of positronium (Ps) atoms for a metal is the negative of the maximum kinetic energy with which Ps is emitted into vacuum when thermalized positrons in a metal encounter the surface. When this quantity is measured by ground state Ps time of flight (TOF), the precision is severely limited by the short triplet state lifetime of 142 ns. By quickly converting the emitted Ps atoms into long-lived Rydberg states, we are able to dramatically increase the TOF to allow precision measurements of A_{Ps}. From our measurements made on a Cu(110) sample at T=128 K, we find A_{Ps}(128 K)=(-2.476±0.010_{stat}±0.013_{syst}) eV, compared with the result A_{Ps}(128 K)=(-2.545±0.010_{num}±0.010_{syst}) eV found using highly accurate generalized gradient approximations for both electrons and positrons within density functional theory. Such precision opens up opportunities in the quest for an improved density functional.

12.
Mol Psychiatry ; 20(1): 118-25, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25199916

RESUMEN

Autism is a heritable disorder, with over 250 associated genes identified to date, yet no single gene accounts for >1-2% of cases. The clinical presentation, behavioural symptoms, imaging and histopathology findings are strikingly heterogeneous. A more complete understanding of autism can be obtained by examining multiple genetic or behavioural mouse models of autism using magnetic resonance imaging (MRI)-based neuroanatomical phenotyping. Twenty-six different mouse models were examined and the consistently found abnormal brain regions across models were parieto-temporal lobe, cerebellar cortex, frontal lobe, hypothalamus and striatum. These models separated into three distinct clusters, two of which can be linked to the under and over-connectivity found in autism. These clusters also identified previously unknown connections between Nrxn1α, En2 and Fmr1; Nlgn3, BTBR and Slc6A4; and also between X monosomy and Mecp2. With no single treatment for autism found, clustering autism using neuroanatomy and identifying these strong connections may prove to be a crucial step in predicting treatment response.


Asunto(s)
Trastorno Autístico/patología , Encéfalo/patología , Modelos Animales de Enfermedad , Familia de Multigenes/genética , Animales , Trastorno Autístico/genética , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Ratones , Ratones Endogámicos BALB C , Ratones Transgénicos
13.
Intern Med J ; 46(10): 1198-1203, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27404498

RESUMEN

BACKGROUND: Aplastic anaemia (AA) is a rare acquired bone marrow failure syndrome resulting from the immune-mediated destruction of haemopoietic stem cells. For adults in whom first-line haemopoietic progenitor cell transplantation is not feasible, combination anti-thymocyte globulin (ATGAM) plus cyclosporine A is standard therapy; however, there are minimal data available regarding the optimal ATGAM dosage in terms of efficacy and survival. AIMS: Our institutions have historically used different dosing protocols of ATGAM in the treatment of AA. We aimed to review the outcome of AA patients treated with these protocols and compare them to the published literature. METHODS: We conducted a retrospective study of 31 adults who received first-line ATGAM for AA and compared response rates and survival between cohorts who received standard (40 mg/kg/day D1-4) versus lower-dose (15 mg/kg/day D1-5) ATGAM schedules. RESULTS: There were similar rates of response (64 vs 71%, P = 1.0), relapse (33 vs 33%, P = 1.0), transformation (14 vs 24%, P = 0.66) or infection (43 vs 47%, P = 1.0), respectively, between standard and lower-dose cohorts. At a median follow up of 24 months, there was no statistical difference between standard and lower-dose cohorts in either event-free (42.2 vs 64.7%, P = 0.91) or overall survival (73.1 vs 88.2%, P = 0.75). CONCLUSION: Our experience suggests that lower-dose ATGAM at 15 mg/kg/day D1-5 as treatment of AA produces similar responses and outcomes as per standard-dose ATGAM schedules. Prospective trials comparing ATGAM dose schedules in AA are warranted.


Asunto(s)
Anemia Aplásica/tratamiento farmacológico , Suero Antilinfocítico/administración & dosificación , Ciclosporina/administración & dosificación , Inmunosupresores/administración & dosificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Australia , Bases de Datos Factuales , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
14.
Intern Med J ; 46(6): 694-702, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27009846

RESUMEN

BACKGROUND: Greater numbers of persons aged over 80 years are admitted to intensive care units (ICU) compared with 15 years ago. Outcomes other than death such as physical dependence and cognitive impairment and treatment burden are important to older people. AIMS: The aims of this study were to determine the long-term outcomes of functional impairment, health-related quality of life (HRQoL) and the self-reported burden of treatment in a sample of patients aged 80 years and above admitted to ICU. Half of the cohort were admitted for elective cardiac surgery, the rest for non-cardiac surgery and medical conditions. METHODS: In this longitudinal cohort study, in a tertiary level ICU, we measured HRQoL using the SF-36 and functional status using the modified Barthel Index at several time points over a 2-year follow-up period. We also assessed treatment burden by asking participants whether they thought the episode of care was worthwhile. RESULTS: A total of 348 patients was recruited into the study. One-fifth of the cohort had died by the 2-year follow-up data collection point. There was an improvement in physical functioning in the cardiac surgery group at 6 months which was not sustained. There was no change in HRQoL at 2 years in either group. The majority valued the episode of care. CONCLUSION: We demonstrated that HRQoL and previous lifestyle is preserved in the majority following ICU admission, associated with a high level of patient valuation of the episode of care.


Asunto(s)
Enfermedad Crónica/mortalidad , Costo de Enfermedad , Cuidados Críticos/normas , Estado de Salud , Calidad de Vida , Anciano de 80 o más Años , Australia , Comorbilidad , Femenino , Hospitales Privados , Humanos , Unidades de Cuidados Intensivos , Estimación de Kaplan-Meier , Estudios Longitudinales , Masculino , Evaluación del Resultado de la Atención al Paciente , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios
15.
Phys Rev Lett ; 114(15): 153201, 2015 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-25933312

RESUMEN

Recently it has been discovered that positronium (Ps), after forming in metal-organic framework (MOF) crystals, is emitted into vacuum with a high efficiency and low energy that can only be explained by its propagating as delocalized Bloch states. We show that the Ps atoms are emitted from MOFs in a series of narrow energy peaks consistent with Ps at Bloch-state energy minima being emitted adiabatically into the vacuum. This implies that the Ps emission energy spectra can be directly compared with calculations to obtain detailed information about the Ps band structure in the MOF crystal. The narrow energy width of the lowest energy Ps peak from one MOF sample (2-Methylimidazole zinc salt ZIF-8) suggests it originates from a polaronic Ps surface state. Other peaks can be assigned to Ps with an effective mass of about twice that of bare Ps. Given the immense catalog of available MOF crystals, it should be possible to tune the Ps properties to make vastly improved sources with high production efficiency and a narrow energy spread, for use in fundamental physics experiments.

17.
HIV Clin Trials ; 15(2): 51-6, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24710918

RESUMEN

BACKGROUND: Pill burden, dosing frequency, and concerns about safety and tolerability are important obstacles to maintaining adequate medication adherence. Raltegravir (RAL) is indicated for twice-daily dosing and when taken with emtricitabine (FTC)/tenofovir disoproxil fumarate (TDF), it becomes a twice-daily multiple-tablet regimen. Elvitegravir (EVG)/cobicistat (COBI)/FTC/TDF, STB, is the first approved once-a-day integrase strand transfer inhibitor (INSTI) containing single-tablet regimen that combines EVG, an INSTI, and COBI, a novel pharmacoenhancer, with the preferred nucleos(t)ide backbone of FTC/TDF. METHODS: This was a 48-week prospective, single-arm open-label study of the switch to STB in virologically sup-pressed HIV-1-infected adult patients on FTC/TDF and twice-daily RAL for at least 6 months. Objectives were to evaluate the tolerability and safety of a regimen simplification to once-a-day STB, while maintaining viral suppression through 48 weeks. RESULTS: Forty-eight individuals in the United States were enrolled. The median age was 44 years, 96% were male, and 83% were White. The median time on RAL + FTC/TDF treatment prior to enrollment was 34 months. Ninety-six percent of participants cited regimen simplification as the reason to enroll in the switch study. At base-line, the median CD4 count was 714 cell/µL and estimated glomerular filtration rate (eGFR) was 105 mL/min. At week 48, all assessed study participants remained viro-logically suppressed to the lower limit of quantification (HIV-1 RNA<50 copies/mL) and maintained high CD4 cell count (median, 751 cells/mL) and stable eGFR (median, 100.5 mL/min). STB was well tolerated with no discontinuations, no study drug-related serious adverse events, and no study drug-related grade 3/4 adverse events. CONCLUSIONS: All participants switching to 1 tablet once-a-day STB from a twice-daily RAL + FTC/TDF regimen remained virologically suppressed. STB was well tolerated. Switching to STB may be a viable option for virologically suppressed patients wanting to simplify from a twice-daily RAL-containing regimen.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Adenina/administración & dosificación , Adenina/efectos adversos , Adenina/análogos & derivados , Adulto , Fármacos Anti-VIH/efectos adversos , Recuento de Linfocito CD4 , Carbamatos/administración & dosificación , Carbamatos/efectos adversos , Cobicistat , Creatinina/sangre , Creatinina/metabolismo , Desoxicitidina/administración & dosificación , Desoxicitidina/efectos adversos , Desoxicitidina/análogos & derivados , Combinación de Medicamentos , Quimioterapia Combinada , Emtricitabina , Femenino , Tasa de Filtración Glomerular/efectos de los fármacos , Humanos , Masculino , Organofosfonatos/administración & dosificación , Organofosfonatos/efectos adversos , Estudios Prospectivos , Pirrolidinonas/administración & dosificación , Pirrolidinonas/efectos adversos , Quinolonas/administración & dosificación , Quinolonas/efectos adversos , Raltegravir Potásico , Tenofovir , Tiazoles/administración & dosificación , Tiazoles/efectos adversos , Resultado del Tratamiento , Estados Unidos , Carga Viral
18.
Intern Med J ; 44(7): 671-5, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24766152

RESUMEN

BACKGROUND: Within Australian hospitals, cardiac and respiratory arrests result in a resuscitation attempt unless the patient is documented as not for resuscitation. AIM: To examine the consistency of policies and documentation for withholding in-hospital resuscitation across health services. METHOD: An observational, qualitative review of hospital policy and documentation was conducted in June 2013 in three public and two private sector hospitals in metropolitan Melbourne. Not for resuscitation (NFR) forms were evaluated for physical characteristics, content, authorisation and decision-making. Hospital policies were coded for alerts, definition of futility and burden of treatment and management of discussions and dissent. RESULTS: There was a lack of standardisation, with each site using its own unique NFR form and accompanying site-specific policies. Differences were found in who could authorise the decision, what was included on the form, the role of patients and families, and how discussions were managed and dissent resolved. Futility and burden of treatment were not defined independently. These inconsistencies across sites contribute to a lack of clarity regarding the decision to withhold resuscitation, and have implications for staff employed across multiple hospitals. CONCLUSIONS: NFR forms should be reviewed and standardised so as to be clear, uniform and consistent with the legislative framework. We propose a two-stage process of documentation. Stage 1 facilitates discussion of patient-specific goals of care and consideration of limitations of treatment. Stage 2 serves to communicate a NFR order. Decisions to withhold resuscitation are inherently complex but could be aided by separating the decision-making process from the communication of the decision, resulting in improved end-of-life care.


Asunto(s)
Servicios de Salud/normas , Hospitalización , Hospitales/normas , Órdenes de Resucitación , Servicios de Salud/ética , Hospitales/ética , Humanos , Órdenes de Resucitación/ética , Victoria/epidemiología
19.
Rev Sci Instrum ; 95(3)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38517258

RESUMEN

We present the development of a versatile apparatus for 6.2 eV laser-based time and angle-resolved photoemission spectroscopy with micrometer spatial resolution (time-resolved µ-ARPES). With a combination of tunable spatial resolution down to ∼11 µm, high energy resolution (∼11 meV), near-transform-limited temporal resolution (∼280 fs), and tunable 1.55 eV pump fluence up to 3 mJ/cm2, this time-resolved µ-ARPES system enables the measurement of ultrafast electron dynamics in exfoliated and inhomogeneous materials. We demonstrate the performance of our system by correlating the spectral broadening of the topological surface state of Bi2Se3 with the spatial dimension of the probe pulse, as well as resolving the spatial inhomogeneity contribution to the observed spectral broadening. Finally, after in situ exfoliation, we performed time-resolved µ-ARPES on a ∼30 µm flake of transition metal dichalcogenide WTe2, thus demonstrating the ability to access ultrafast electron dynamics with momentum resolution on micro-exfoliated materials.

20.
HIV Med ; 14(7): 391-400, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23298380

RESUMEN

OBJECTIVES: The aim of the study was to compare the neuropsychiatric safety and tolerability of rilpivirine (TMC278) vs. efavirenz in a preplanned pooled analysis of data from the ECHO and THRIVE studies which compared the safety and efficacy of the two drugs in HIV-1 infected treatment naïve adults. METHODS: ECHO and THRIVE were randomized, double-blind, double-dummy, 96-week, international, phase 3 trials comparing the efficacy, safety and tolerability of rilpivirine 25 mg vs. efavirenz 600 mg once daily in combination with two background nucleoside/tide reverse transcriptase inhibitors. Safety and tolerability analyses were conducted when all patients had received at least 48 weeks of treatment or discontinued earlier. Differences between treatments in the incidence of neurological and psychiatric adverse events (AEs) of interest were assessed in preplanned statistical analyses using Fisher's exact test. RESULTS: At the time of the week 48 analysis, the cumulative incidences in the rilpivirine vs. efavirenz groups of any grade 2-4 treatment-related AEs and of discontinuation because of AEs were 16% vs. 31% (P<0.0001) and 3% vs. 8% (P=0.0005), respectively. The incidence of treatment-related neuropsychiatric AEs was 27% vs. 48%, respectively (P<0.0001). The incidence of treatment-related neurological AEs of interest was 17% vs. 38% (P<0.0001), and that of treatment-related psychiatric AEs of interest was 15% vs. 23% (P=0.0002). Dizziness and abnormal dreams/nightmares occurred significantly less frequently with rilpivirine vs. efavirenz (P<0.01). In both groups, patients with prior neuropsychiatric history tended to report more neuropsychiatric AEs but rates remained lower for rilpivirine than for efavirenz. CONCLUSIONS: Rilpivirine was associated with fewer neurological and psychiatric AEs of interest than efavirenz over 48 weeks in treatment-naïve, HIV-1-infected adults.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Benzoxazinas/efectos adversos , Infecciones por VIH/tratamiento farmacológico , VIH-1 , Trastornos Mentales/inducido químicamente , Enfermedades del Sistema Nervioso/inducido químicamente , Nitrilos/efectos adversos , Pirimidinas/efectos adversos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alquinos , Fármacos Anti-VIH/farmacología , Fármacos Anti-VIH/uso terapéutico , Benzoxazinas/administración & dosificación , Benzoxazinas/uso terapéutico , Ciclopropanos , Infecciones por VIH/psicología , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , VIH-1/fisiología , Humanos , Persona de Mediana Edad , Nitrilos/administración & dosificación , Nitrilos/uso terapéutico , Pirimidinas/administración & dosificación , Pirimidinas/uso terapéutico , Rilpivirina , Carga Viral/fisiología , Adulto Joven
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