Synthesis, photo- and thermo-luminescent properties of Mg2P2O7:Tm3+ phosphors.

In this work, both undoped and Thulium (Tm3+) doped (0.3-10 mol%) magnesium pyrophosphate (Mg2P2O7) powders were synthesized by the solvent evaporation method to study their photo-and thermoluminescent properties. Two crystalline phases were observed in the powders by X-Ray diffraction (XRD), the main phase being Mg2P2O7 and the second one thulium phosphate (TmPO4). The superficial morphology was analyzed by scanning electron microscopy (SEM), which revealed that the powders are agglomerates with an undefined form and grains with non-uniform size distribution. The photoluminescence (PL) emission spectra of Tm3+ doped powders show the 1D2 → 3F4 transition, associated with Tm3+ ions, at 452 and 458 nm. The thermoluminescence (TL) properties were analyzed in the undoped and Tm3+ doped powders exposed to 90Sr beta source. The TL glow curve of Tm3+ doped powders exhibits three maxima at about ⁓64-66 °C, ⁓198-202 °C, and ⁓301 °C. The TL dose-response is sub-linear from 0.11 to 0.54 Gy, linear between 0.79 and 24.95 Gy, and supra-linear from 34.99 to 599.95 Gy. Acceptable repeatability with a coefficient of variation of ∼1% was obtained after ten cycles of irradiation and readout. At 63 d of storage, the powders show fading of 30%, and at 1.6 years (585 d), the integrated TL intensity decays by 47%. The kinetic parameters of activation energy and frequency factor were evaluated using the Initial Rise, Booth, Bohun, and Porfianovitch (BBP) and Hoogenstraaten methods and Glow Curve Deconvolution with a general order kinetic model.

New Insights for the Renewed Phytoplankton-Bacteria Coupling Concept: the Role of the Trophic Web.

It is widely accepted that in many aquatic ecosystems bacterioplankton is dependent on and regulated by organic carbon supplied by phytoplankton, leading to coupled algae-bacteria relationship. In this study, an in-depth analysis of this relationship has been carried out by combining two approaches: (i) a correlation analyses between heterotrophic bacterial production (BP) vs. primary production (PP) or algal excretion of organic carbon (EOC), (ii) the balance between bacterial carbon demands (BCD) and the supply of C as EOC, measured as BCD:EOC ratio. During the study period (2013-2016), the algae-bacteria relationship was constantly changing from a coupling in 2013, uncoupling in 2014 and 2015, and an incipient return to coupling (in 2016). Our results show that top-down control (bacterivory) by algal mixotrophy acts as a decoupling force since it provides a fresh C source different to algal EOC to satisfy bacterial carbon demands. Notably, a relationship between the BCD:EOC ratio and the ecosystem metabolic balance (Primary production (PP): respiration (R)) was found, suggesting that PP:R may be a good predictor of the algae-bacteria coupling. This analysis, including the comparison between basal and potential ecosystem metabolic balance, can be a tool to improve knowledge on the interaction between both biotics compartments, which the traditional analyses on coupling may not capture.

Thermoluminescence properties and identification of irradiated cocoa beans during long-term storage.

This work reports on the thermoluminescence (TL) properties and detection of contaminating minerals isolated from Mexican cocoa beans irradiated with gamma radiation and stored for 4 years. Contaminating minerals isolated from cocoa beans consisting of quartz, diopside, plagioclase, albite, and iron oxide with irregular and rectangular grains and average length of 135 µm. Cocoa beans are detected as irradiated even after 4 years of storage using the shape and maximum temperature of the TL glow curve of contaminating minerals. The TL properties of dose-response, and fading of minerals were also analysed. The TL dose-response is linear from 5 to 100 Gy, supra-linear between 250 and 1000 Gy, and sub-linear above 1500 Gy. Based on the TL1/TL2 ratio the minerals are identified as irradiated from 250 Gy to 4500 Gy in the dose-response test and after different storage times in the darkness at room temperature. A continuum trap distribution can be associated with the TL glow curve of minerals using the Tm-Tstop method. First order kinetic peaks were used in the Glow Curve Deconvolution of natural and irradiated (1 and 10 kGy) TL curves.

Registro español de desfibrilador automático implantable. XVIII informe oficial de la Asociación del Ritmo Cardiaco de la Sociedad Española de Cardiología (2021) / Spanish implantable cardioverter-defibrillator registry. 18th official report of the Heart Rhythm Association of the Spanish Society of Cardiology (2021)

Introducción y objetivos Se presentan los datos correspondientes a los implantes de desfibrilador automático implantable (DAI) en España en el año 2021. Métodos Los datos provienen de los centros implantadores, que cumplimentaron voluntariamente una hoja de recogida de datos durante el implante. Resultados En 2021 se recibieron 7.496 formularios de implante, frente a los 7.743 comunicadas por Eucomed (European Confederation of Medical Suppliers Associations), lo que implica que se han recogido datos del 96,8% de los dispositivos implantados en España. El cumplimiento osciló entre el 99,9% en el campo «nombre del hospital implantador» y el 8,9% en la variable «hospital de referencia». En 2021, 199 hospitales han participado en el registro, lo cual supera las cifras de los años previos en que el número de participantes osciló alrededor de 170 hospitales. La tasa total de implantes registrados fue 158/millón de habitantes (163 según Eucomed), lo que la sitúa como el año con mayor actividad. Sin embargo, el registro sigue mostrando diferencias importantes entre las comunidades autónomas y la tasa de implante más baja de todos los países europeos participantes en Eucomed. Conclusione El Registro español de desfibrilador automático implantable del año 2021 recoge un incremento en el número de implantes de DAI y refleja la recuperación de la actividad hospitalaria tras el impacto inicial de la pandemia por COVID-19 durante 2020. A pesar del incremento en el número total de implantes en España, este sigue siendo muy inferior a la media de la Unión Europea y persisten las diferencias entre las comunidades autónomas españolas (AU)

Introduction and objectives This article presents the data corresponding to implantable cardioverter-defibrillator (ICD) implantations in Spain in 2021. Methods The data were drawn from implanting centers, which voluntarily completed a data collection sheet during the procedure. Results In 2021, 7496 implant data sheets were received, compared with 7743 reported by Eucomed (European Confederation of Medical Suppliers Associations), indicating that data were collected from 96.8% of the devices implanted in Spain. Data completion ranged from 99.9% for “name of implanting hospital” to 8.9% for “implanting hospital”. In 2021, 199 hospitals participated in the registry, exceeding the figures of previous years, with around 170 participating hospitals. The total rate of registered implants was 158/million inhabitants (163 according to Eucomed), making 2021 the year with the highest activity. However, the registry continues to show significant differences among the various autonomous communities and the lowest implantation rate of all the European countries participating in Eucomed. Conclusions The Spanish implantable cardioverter-defibrillator registry for 2021 recorded an increase in the number of ICD implantations, reflecting the recovery of hospital activity after the initial impact of the COVID-19 pandemic in 2020. Although the total number of implants has increased in Spain, figures are still much lower than the European Union average, with differences persisting among Spanish autonomous communities (AU)

Continuous-wave optically stimulated luminescence properties of Guajillo chilli polyminerals exposed to gamma radiation.

In this investigation, the Continuous-Wave Optically Stimulated Luminescence (CW-OSL) properties of polyminerals extracted from Mexican and Peruvian Guajillo chilli were studied using a source of cesium-137 (Cs-137) gamma radiation. The Guajillo chilli polyminerals were stimulated with blue light for 120 s, and their luminescence was detected in the UV region. The General Order Kinetics (GOK) deconvolution analysis of the CW-OSL curves was carried out using three individual components. The CW-OSL dose response from 10 to 5000 Gy was analysed in Guajillo chilli polyminerals. After different storage periods, the polyminerals show an increase in the CW-OSL intensity. A strong and moderate effect of the sunlight (60 min) and artificial (6 h) light is observed on the CW-OSL response. Therefore, the CW-OSL properties of polyminerals could be used in the identification of Mexican and Peruvian Guajillo chilli exposed to Cs-137 gamma radiation.

Alteración de señal periictal transitoria en resonancia magnética de encéfalo simulando lesión estructural: caso clínico / Reversible peri-ictal MRI signal changes mimicking structural lesion: case report

Resumen La presencia de alteraciones de señal en resonancia magnética (RM) cerebral durante o posterior a un evento epiléptico es cada vez más reconocida en la literatura. Los cambios de señal peri-ictales se considera que sería el resultado de edema cerebral localizado, defecto de la autorregulación cerebral y disrupción de la barrera hemato-encefálica que ocurre durante una crisis epiléptica sostenida. Reportamos el caso de un hombre de 62 años diagnosticado de un síndrome parietal de instalación subaguda cuyo estudio con RM de cerebro mostró una lesión tumefacta con edema cortico-subcortical de ubicación temporo-occipital derecha. El estudio con electroencefalograma mostró actividad ictal en la misma localización. Se inició terapia con fármacos anticonvulsivantes mostrando franca mejoría clínica y electrofisiológica. El control con RM diferido mostró resolución completa de las alteraciones descritas.

The presence seizure-induced signal changes on brain magnetic resonance imaging (MRI) have been increasingly recognized in the literature. The reversible MRI changes in epileptic patients may be the result of a local brain swelling, a defect of cerebral autoregulation and a blood-brain barrier disruption during sustained epileptogenic activity. We report a 62 years old man diagnosed with a subacute right parietal syndrome. MRI shows a tumefactive lesion in right temporo-occipital lobes mimicking a structural lesion. Electroencephalogram (EEG) exhibits continuous ictal activity in the same region. Antiepileptic drugs were started achieving progressive electro-clinical improvement. Subsequent MRI showed remission of signal changes.

Improvements in beam's eye view fiducial tracking using a novel multilayer imager.

Purpose.Electronic portal image devices (EPIDs) have been investigated previously for beams-eye view (BEV) applications such as tumor tracking but are limited by low contrast-to-noise ratio and detective quantum efficiency. A novel multilayer imager (MLI), consisting of four stacked flat-panels was used to measure improvements in fiducial tracking during liver stereotactic body radiation therapy (SBRT) procedures compared to a single layer EPID.Methods.The prototype MLI was installed on a clinical TrueBeam linac in place of the conventional DMI single-layer EPID. The panel was extended during volumetric modulated arc therapy SBRT treatments in order to passively acquire data during therapy. Images were acquired for six patients receiving SBRT to liver metastases over two fractions each, one with the MLI using all 4 layers and one with the MLI using the top layer only, representing a standard EPID. The acquired frames were processed by a previously published tracking algorithm modified to identify implanted radiopaque fiducials. Truth data was determined using respiratory traces combined with partial manual tracking. Results for 4- and 1-layer mode were compared against truth data for tracking accuracy and efficiency. Tracking and noise improvements as a function of gantry angle were determined.Results. Tracking efficiency with 4-layers improved to 82.8% versus 58.4% for the 1-layer mode, a relative improvement of 41.7%. Fiducial tracking with 1-layer returned a root mean square error (RMSE) of 2.1 mm compared to 4-layer RMSE of 1.5 mm, a statistically significant (p < 0.001) improvement of 0.6 mm. The reduction in noise correlated with an increase in successfully tracked frames (r = 0.913) and with increased tracking accuracy (0.927).Conclusion. Increases in MV photon detection efficiency by utilization of a MLI results in improved fiducial tracking for liver SBRT treatments. Future clinical applications utilizing BEV imaging may be enhanced by including similar noise reduction strategies.

Clinical translation of a new flat-panel detector for beam's-eye-view imaging.

Electronic portal imaging devices (EPIDs) lend themselves to beams-eye view clinical applications, such as tumor tracking, but are limited by low contrast and detective quantum efficiency (DQE). We characterize a novel EPID prototype consisting of multiple layers and investigate its suitability for use under clinical conditions. A prototype multi-layer imager (MLI) was constructed utilizing four conventional EPID layers, each consisting of a copper plate, a Gd2O2S:Tb phosphor scintillator, and an amorphous silicon flat panel array detector. We measured the detector's response to a 6 MV photon beam with regards to modulation transfer function, noise power spectrum, DQE, contrast-to-noise ratio (CNR), signal-to-noise ratio (SNR), and the linearity of the detector's response to dose. Additionally, we compared MLI performance to the single top layer of the MLI and the standard Varian AS-1200 detector. Pre-clinical imaging was done on an anthropomorphic phantom, and the detector's CNR, SNR and spatial resolution were assessed in a clinical environment. Images obtained from spine and liver patient treatment deliveries were analyzed to verify CNR and SNR improvements. The MLI has a DQE(0) of 9.7%, about 5.7 times the reference AS-1200 detector. Improved noise performance largely drives the increase. CNR and SNR of clinical images improved three-fold compared to reference. A novel MLI was characterized and prepared for clinical translation. The MLI substantially improved DQE and CNR performance while maintaining the same resolution. Pre-clinical tests on an anthropomorphic phantom demonstrated improved performance as predicted theoretically. Preliminary patient data were analyzed, confirming improved CNR and SNR. Clinical applications are anticipated to include more accurate soft tissue tracking.

Reproducibilidad de la medición manual del grosor coroideo utilizando la tomografía de coherencia óptica / Reproducibility of manual choroidal thickness measurements using optical coherence tomography

OBJETIVO: La tomografía de coherencia óptica de dominio espectral (SD-OCT) es la herramienta de mayor utilidad para medir el grosor coroideo (GC). El GC puede estar aumentado tanto en las enfermedades oftalmológicas como en las sistémicas. No obstante, existen ciertas inquietudes en relación con la reproducibilidad y la validez externa de la OCT. El objetivo de este estudio fue determinar la variabilidad interobservador e intraobservador de la medición manual de la OCT. MÉTODOS: El GC fue medido de manera manual en la región central en 40 ojos de 21 sujetos (11 sanos y 10 con espondilitis anquilosante) utilizando RTVue-100 OCT (Optovue Inc., Fremont, CA, EE.UU.). Las mediciones fueron obtenidas por 9 oftalmólogos independientes de 6 centros diferentes. Para determinar la variabilidad interobservador se utilizó el cálculo del coeficiente de correlación intraclase (CCI). También la variabilidad intraobservador fue determinada en 2 de los oftalmólogos. RESULTADOS: La media del GC subfoveal fue de 364,9 ± 85,1μm (rango, 170-572). El CCI interobservador fue 0,823 (IC 95%, 0,749-0,888; p < 0,001). El CCI intraobservador fue 0,885 (IC 95%, 0,783-0,939; p < 0,001) y 0,925 (IC 95%, 0,859-0,960; p < 0,001). CONCLUSIONES: En este estudio la medición manual del GC ha demostrado buena concordancia. Los resultados sugieren que la medición manual con la OCT es un método válido para los estudios multicéntricos

PURPOSE: Spectral-domain optical coherence tomography (SD-OCT) is the most useful tool to measure choroidal thickness (CT). CT may be increased in ocular and systemic diseases. However, there are concerns relating reproducibility and external validity of OCT. The aim of this study was to assess the inter-observer and intra-observer variability of manual OCT measurements. METHODS: CT was manually measured in the central choroid of 40 eyes from 21 subjects (11 healthy and 10 with ankylosing spondylitis) using RTVue-100 OCT (Optovue Inc., Fremont, CA, EE.UU.). Measurements were performed by 9 independent ophthalmologists from 6 different centers. To assess the inter-observer variability, the intra-class correlation coefficient (ICC) method was calculated. Also, intra-observer variability was assessed in 2 of the ophthalmologists. RESULTS: The mean subfoveal CT was 364.9 ± 85.1μm (range, 170 to 572). The inter-observer ICC was 0.823 (CI 95%, 0.749 to 0.888, p < 0.001). The intra-observer ICCs were 0.885 (CI 95%, 0.783 to 0.939, p < 0.001) and 0.925 (CI 95%, 0.859 to 0.960. p < 0.001). CONCLUSIONS: In this study, manual measurements of CT with OCT showed a good concordance. These results suggest that manual OCT is a valid tool for multicenter studies

A hexavalent Coxsackievirus B vaccine is highly immunogenic and has a strong protective capacity in mice and nonhuman primates.

Coxsackievirus B (CVB) enteroviruses are common human pathogens known to cause severe diseases including myocarditis, chronic dilated cardiomyopathy, and aseptic meningitis. CVBs are also hypothesized to be a causal factor in type 1 diabetes. Vaccines against CVBs are not currently available, and here we describe the generation and preclinical testing of a novel hexavalent vaccine targeting the six known CVB serotypes. We show that the vaccine has an excellent safety profile in murine models and nonhuman primates and that it induces strong neutralizing antibody responses to the six serotypes in both species without an adjuvant. We also demonstrate that the vaccine provides immunity against acute CVB infections in mice, including CVB infections known to cause virus-induced myocarditis. In addition, it blocks CVB-induced diabetes in a genetically permissive mouse model. Our preclinical proof-of-concept studies demonstrate the successful generation of a promising hexavalent CVB vaccine with high immunogenicity capable of preventing CVB-induced diseases.

Reproducibility of manual choroidal thickness measurements using optical coherence tomography. / Reproducibilidad de la medición manual del grosor coroideo utilizando la tomografía de coherencia óptica.

PURPOSE: Spectral-domain optical coherence tomography (SD-OCT) is the most useful tool to measure choroidal thickness (CT). CT may be increased in ocular and systemic diseases. However, there are concerns relating reproducibility and external validity of OCT. The aim of this study was to assess the inter-observer and intra-observer variability of manual OCT measurements. METHODS: CT was manually measured in the central choroid of 40 eyes from 21 subjects (11 healthy and 10 with ankylosing spondylitis) using RTVue-100 OCT (Optovue Inc., Fremont, CA, EE.UU.). Measurements were performed by 9 independent ophthalmologists from 6 different centers. To assess the inter-observer variability, the intra-class correlation coefficient (ICC) method was calculated. Also, intra-observer variability was assessed in 2 of the ophthalmologists. RESULTS: The mean subfoveal CT was 364.9±85.1µm (range, 170 to 572). The inter-observer ICC was 0.823 (CI 95%, 0.749 to 0.888, p<0.001). The intra-observer ICCs were 0.885 (CI 95%, 0.783 to 0.939, p<0.001) and 0.925 (CI 95%, 0.859 to 0.960. p<0.001). CONCLUSIONS: In this study, manual measurements of CT with OCT showed a good concordance. These results suggest that manual OCT is a valid tool for multicenter studies.

Automated MV markerless tumor tracking for VMAT.

Tumor tracking during radiotherapy treatment can improve dose accuracy, conformity and sparing of healthy tissue. Many methods have been introduced to tackle this challenge utilizing multiple imaging modalities, including a template matching based approach using the megavoltage (MV) on-board portal imager demonstrated on 3D conformal treatments. However, the complexity of treatments is evolving with the introduction of VMAT and IMRT, and successful motion management is becoming more important due to a trend towards hypofractionation. We have developed a markerless lung tumor tracking algorithm, utilizing the electronic portal imager (EPID) of the treatment machine. The algorithm has been specifically adapted to track during complex treatment deliveries with gantry and MLC motion. The core of the algorithm is an adaptive template matching method that relies on template stability metrics and local relative orientations to perform multiple feature tracking simultaneously. Only a single image is required to initialize the algorithm and features are automatically added, modified or removed in response to the input images. This algorithm was evaluated against images collected during VMAT arcs of a dynamic thorax phantom. Dynamic phantom images were collected during radiation delivery for multiple lung SBRT breathing traces and an example patient data set. The tracking error was 1.34 mm for the phantom data and 0.68 mm for the patient data. A multi-region, markerless tracking algorithm has been developed, capable of tracking multiple features simultaneously without requiring any other a priori information. This novel approach delivers robust target localization during complex treatment delivery. The reported tracking error is similar to previous reports for 3D conformal treatments.

Riesgo de enfermedad cardiovascular en pacientes con infección VIH en tratamiento antirretroviral / Risk of cardiovascular disease in patients with HIV infection undergoing antiretroviral therapy

ANTECEDENTES: La mayor supervivencia de los pacientes con infección por VIH gracias al tratamiento antirretroviral (TAR) se acompaña de una mayor frecuencia de enfermedad cardiovascular (ECV). Analizamos la prevalencia de los factores de riesgo cardiovascular (FRCV) y la estimación del riesgo de ECV en una cohorte de personas con infección por VIH en España. MÉTODOS: Estudio transversal, observacional de los FRCV en la cohorte española VACH de pacientes con infección por VIH que recibían TAR. RESULTADOS: Se evaluaron 15.559 pacientes con infección por VIH (76% varones; edad media: 46 años). Un 3,7% había experimentado al menos un evento de ECV. La prevalencia de FRCV era elevada: hiperlipidemia, 64%; tabaquismo, 47%; HTA, 22%; y diabetes, 16%. Según la escala Framingham, un 10,9% presentaba alto riesgo de ECV y un 28,8% riesgo moderado. De los pacientes con elevado riesgo de ECV, el 49% recibía inhibidores de proteasa y el 43% abacavir. Se usaron fármacos hipotensores en el 53% de los pacientes con diagnóstico de HTA, y fármacos antidiabéticos en el 2,6% de los pacientes con diabetes. CONCLUSIONES: Los FRCV tradicionales son frecuentes en los pacientes con infección por VIH con TAR en España, y una elevada proporción de ellos tiene riesgo moderado-alto de ECV. Por tanto, el control de los FRCV modificables en los pacientes con infección por VIH debería mejorarse y valorar el uso de fármacos con mejor perfil de riesgo cardiovascular

BACKGROUND: The increased survival of patients with HIV infection thanks to antiretroviral therapy (ART) is accompanied by a higher rate of cardiovascular disease (CVD). We analysed the prevalence of the cardiovascular risk factors (CRFs) and estimated the risk of CVD in a cohort of patients with HIV in Spain. METHODS: We conducted a cross-sectional, observational study of CRFs in the Spanish VACH cohort of patients with HIV who undergo ART. RESULTS: The study assessed 15,559 patients with HIV (76% men; mean age, 46 years). Some 3.7% had experienced at least 1 CVD event. The prevalence of CRFs was high (hyperlipidaemia, 64%; tobacco use, 47%; arterial hypertension, 22%; and diabetes, 16%). According to the Framingham scale, 10.9% of the patients presented a high CVD risk, and 28.8% presented a moderate risk. Of the patients with a high CVD risk, 49% took protease inhibitors and 43% took abacavir. Fifty-three percent of the patients diagnosed with arterial hypertension took antihypertensive drugs, and 2.6% of the patients with diabetes took antidiabetic agents. CONCLUSIONS: Classical CRFs are common in patients with HIV undergoing ART in Spain, and a large proportion of them have a moderate-high risk of CVD. Therefore, controlling the modifiable CRFs in patients with HIV should be improved, and the use of drugs with a better cardiovascular risk profile should be assessed

Risk of cardiovascular disease in patients with HIV infection undergoing antiretroviral therapy. / Riesgo de enfermedad cardiovascular en pacientes con infección VIH en tratamiento antirretroviral.

BACKGROUND: The increased survival of patients with HIV infection thanks to antiretroviral therapy (ART) is accompanied by a higher rate of cardiovascular disease (CVD). We analysed the prevalence of the cardiovascular risk factors (CRFs) and estimated the risk of CVD in a cohort of patients with HIV in Spain. METHODS: We conducted a cross-sectional, observational study of CRFs in the Spanish VACH cohort of patients with HIV who undergo ART. RESULTS: The study assessed 15,559 patients with HIV (76% men; mean age, 46 years). Some 3.7% had experienced at least 1 CVD event. The prevalence of CRFs was high (hyperlipidaemia, 64%; tobacco use, 47%; arterial hypertension, 22%; and diabetes, 16%). According to the Framingham scale, 10.9% of the patients presented a high CVD risk, and 28.8% presented a moderate risk. Of the patients with a high CVD risk, 49% took protease inhibitors and 43% took abacavir. Fifty-three percent of the patients diagnosed with arterial hypertension took antihypertensive drugs, and 2.6% of the patients with diabetes took antidiabetic agents. CONCLUSIONS: Classical CRFs are common in patients with HIV undergoing ART in Spain, and a large proportion of them have a moderate-high risk of CVD. Therefore, controlling the modifiable CRFs in patients with HIV should be improved, and the use of drugs with a better cardiovascular risk profile should be assessed.

Synthesis of ß-Ca2P2O7:Tb3+ to gamma radiation detection by thermoluminescence.

In this work, luminescent emissions of beta-calcium pyrophosphate doped with terbium ions (ß-Ca2P2O7:Tb3+) were studied. The Ca2P2O7:Tb3+ powders were prepared by precipitation and annealed at 900°C for 2h was applied on the powders to observe the beta phase. Radioluminescence measurements showed emission bands related with 5D3 (5D4)→7FJ transitions of Tb3+ ions. Three overlapped peaks at 126, 165 and 220°C were observed in thermoluminescence response. A linear TL dose-response in the range of 0.2-10Gy and an acceptable TL reproducibility were showed by the ß-Ca2P2O7:Tb3+ samples exposed to 60Co gamma radiation. The TL glow curves were analyzed by Initial Rise method and Computational Glow-Curve Deconvolution assuming a General Order Kinetic model to evaluate the kinetic parameters related with the TL peaks.

Simplification to dual therapy (atazanavir/ritonavir + lamivudine) versus standard triple therapy [atazanavir/ritonavir + two nucleos(t)ides] in virologically stable patients on antiretroviral therapy: 96 week results from an open-label, non-inferiority, randomized clinical trial (SALT study).

OBJECTIVES: We evaluated whether maintenance therapy with atazanavir/ritonavir plus lamivudine (ATV/r + 3TC) was non-inferior to ATV/r plus two nucleosides (ATV/r + 2NUCs) at 96 weeks of follow-up. METHODS: SALT is a multicentre, open-label, non-inferiority clinical trial in HIV-1-infected virologically suppressed patients. Hepatitis B virus surface antigen-negative subjects with no previous treatment failure/resistance mutations and HIV-1-RNA <50 copies/mL for ≥6 months were randomized (1 : 1) to ATV/r + 3TC or ATV/r + 2NUCs. The primary endpoint was HIV-1-RNA <50 copies/mL in the PP population. Non-inferiority was demonstrated if the lower bound of the 95% CI for the difference was not below -12%. RESULTS: Some 286 patients were analysed. At week 96, 74.4% had HIV-1-RNA <50 copies/mL in the ATV/r + 3TC arm versus 73.9% in the ATV/r + 2NUCs arm (95% CI for the difference, -9.9%-11.0%). In both groups, similar values were observed for patients with confirmed virological failure in ATV/r + 3TC versus ATV/r + 2NUCs (9 versus 5), death (1 versus 0), discontinuation due to ART-related toxicity (7 versus 11), withdrawal from the study (7 versus 9) and loss to follow-up (6 versus 6). One patient taking ATV/r + 2NUCs developed resistance mutations (M184V and L63P). Similar values were obtained for change in mean CD4 count [19 versus 18 cells/mm3 (95% CI for the difference, -49.3-50.7), grade 3-4 adverse events (70.7% versus 70.2%) and changes in the global deficit score, -0.3 (95% CI, -0.5 to -0.1) for ATV/r + 3TC, versus -0.2 (95% CI, -0.4 to -0.1) for ATV/r + 2NUCs]. CONCLUSIONS: The long-term results of switching to ATV/r + 3TC show that this strategy is effective, safe and non-inferior to ATV + 2NUCs in virologically suppressed HIV-infected patients.

Very low level viraemia and risk of virological failure in treated HIV-1-infected patients.

OBJECTIVES: The aim of the study was to investigate whether very low level viraemia (VLLV) (20-50 HIV-1 RNA copies/mL) was associated with increased risk of virological failure (VF) as compared with persistent full suppression (< 20 copies/mL). METHODS: From the VACH Cohort database, we selected those patients who started antiretroviral therapy (ART) after January 1997 and who achieved effective viral suppression [two consecutive viral loads (VLs) < 50 copies/mL] followed by full suppression (at least one VL <20 copies/mL). We carried out survival analyses to investigate whether the occurrence of VLLV rather than maintaining full suppression at < 20 copies/mL was associated with virological failure (two consecutive VLs > 200 copies/mL or one VL > 200 copies/mL followed by a change of ART regimen, administrative censoring or loss to follow-up), adjusted for nadir CD4 cell count, sex, age, ethnicity, transmission group, type of ART and time on effective suppression at < 50 copies/mL. RESULTS: Of 21 480 patients who started ART, 13 674 (63.7%) achieved effective suppression at < 50 copies/mL, of whom 4289 (31.4%) further achieved full suppression at < 20 copies/mL after May 2009. A total of 2623 patients (61.1%) remained fully suppressed thereafter, while 1666 had one or more episodes of VL detection > 20 copies/mL (excluding virological failure). A total of 824 patients had VLLV after suppression at < 20 copies/mL. VLLV was not associated with virological failure as compared with persistent full suppression [hazard ratio (HR) 0.67; 95% confidence interval (CI) 0.44-1.00], independently of the number of blips recorded (from one to 18). CONCLUSIONS: In our population of HIV-infected patients on ART who achieved viral suppression at < 20 copies/mL, the risk of virological failure was no different for patients who remained fully suppressed compared with those who experienced subsequent episodes of VLLV.

The diversity of the human hair colour assessed by visual scales and instrumental measurements. A worldwide survey.

OBJECTIVES: To study (i) the diversity of the natural colour of the human hair through both visual assessment of hair tone levels and colorimetric measurements of hair strands collected from 2057 human male and female volunteers, from 23 regions of the world and (ii) the correlation between visual assessments and colorimetric measurements. METHODS: Hair strands were analysed by a spectrocolorimeter under the L*, a*, b* referential system and scored in vivo by experts before sampling, through standardized visual reference scales based on a 1-10 range. RESULTS: Results show that from a typological aspect, black or dark brown hairs largely predominate among studied ethnic groups, whereas Caucasian or derived populations exhibit the widest palette of medium to fair shades, partly explaining some past interbreeding among populations. Instrumental measurements clearly confirm that a given colour of a pigmented hair, at the exclusion of red hairs, is mostly governed by two components, L* and b*, from the L*, a*, b* reference system. CONCLUSION: The comparisons between visual assessments and instrumental data show that these appear closely linked. Darker hairs show close or subtle variations in L*, a*, b* parameters, making their individual colour differentiation calling for technical improvements in colorimetric measurements. The latter are likely governed by other physical factors such as shape, diameter and shine.