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1.
Phys Rev Lett ; 127(27): 275901, 2021 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-35061440

RESUMEN

The ultrafast electron energy transport is investigated in laser-heated warm dense copper in a high flux regime (2.5±0.7×10^{13} W/cm^{2} absorbed). The dynamics of the electron temperature is retrieved from femtosecond time-resolved x-ray absorption near-edge spectroscopy near the Cu L3 edge. A characteristic time of ∼1 ps is observed for the increase in the average temperature in a 100 nm thick sample. Data are well reproduced by two-temperature hydrodynamic simulations, which support energy transport dominated by thermal conduction rather than ballistic electrons.

2.
J Dairy Sci ; 104(5): 5675-5688, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33663858

RESUMEN

Monitoring liveweight (LW) is an important part of sound management practices at the individual and flock level (e.g., controlling for nutritional status based on body condition, reproduction, and health-related issues), but it is time consuming and stressful. To our knowledge, no literature has reported on the evaluation of automated weighing systems in dairy sheep as an alternative to conventional static scales. The objective of this research was to evaluate the practical feasibility of using an automated walk-over-weighing (WoW) prototype to measure daily LW changes in dairy ewes without human intervention. We used adult Lacaune dairy ewes in 2 complementary trials conducted indoors. Trial 1 aimed at evaluating the repeatability, precision, and accuracy of LW measures recorded using WoW scales compared with a static scale (the gold standard). Forty-two adult ewes (LW ± standard deviation = 71.3 ± 10.4 kg) were randomly drafted from the main flock and used in a 1-day session. The trial included 3 passages. In each passage, ewes were weighed first on a static scale; once a static position was achieved and LW recorded, they continued the circuit and immediately traversed the WoW scale for an automated LW record. Trial 2 aimed to demonstrate the feasibility of using the WoW device under real-world conditions in a dairy sheep-farming system. The WoW scale was installed in the exit race of the milking parlor and evaluated over 7 wk with adult ewes in mid lactation (n = 93; LW 78.5 ± 8.1 kg). Once the ewes were acclimated to the WoW system, 1 group of ewes (n = 48) continued to receive the same feeding regimen (controls), and the other group (n = 45) underwent a nutritional challenge [challenged; 2 wk of undernutrition and then back to control regimen (refeeding) for 1 wk]. We evaluated the ability of the WoW to detect small changes in LW. We collected LW data (2 weighings per ewe per day) from the WoW after each of the 2 milking sessions (morning and evening). We also obtained LW values by weighing the ewes using a static scale once a week. The automated WoW system showed substantial agreement with the gold standard when assessed using Lin's concordance correlation coefficient and Bland and Altman's method, largely due to high repeatability. The WoW system was adequate for detecting small daily variations in LW during undernutrition and refeeding periods. Misbehaviors resulted in spurious WoW values in trial 2, requiring us to use filtration methods to exclude outlier weights and allow meaningful assessment of small LW changes. The WoW system evaluated here is an alternative to the static scales conventionally used on dairy sheep farms. If sound filtration of raw data is applied, WoW could contribute to the close (daily) monitoring of individual LW without operator intervention (i.e., voluntary weighing) and taking animal welfare into account (i.e., no stress related to the weighing session on static scales).


Asunto(s)
Lactancia , Leche , Animales , Peso Corporal , Ingestión de Alimentos , Femenino , Reproducción , Ovinos
3.
Phys Rev Lett ; 124(13): 133902, 2020 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-32302194

RESUMEN

We report evidence of strong lasing on the 4p-4s transition at 62.7 nm in nickel-like krypton occurring simultaneously with the usual 4d-4p lasing at 32.8 nm. The gain dynamics of both transitions were experimentally and numerically investigated and found comparable. The two-color amplifier was seeded by the same harmonic pulse, therefore producing a short-duration coherent two-color soft x-ray laser pulse. Both transitions offer similar prospects of pulse energy and duration and could lead to the delivery of intense and ultrashort two-color coherent soft x-ray pulses with a controllable delay.

4.
Br J Dermatol ; 182(2): 477-480, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31077337

RESUMEN

Immune checkpoint inhibitors are now the standard of care in the treatment of several types of cancer. Cutaneous immune-related adverse events (irAEs) are usually of low grade and reversible, while endocrine irAEs are generally irreversible and managed with hormone replacement therapy. We report a 47-year-old patient, treated with the anti-programmed cell death (PD)1 antibody pembrolizumab for a metastatic melanoma, who developed severe lipodystrophy after 10 months of treatment, characterized by the loss of subcutaneous fat tissue, central obesity and insulin resistance with a decreased leptin level. Histological analysis of a cutaneous biopsy revealed subcutaneous fat cell destruction associated with oedema, the presence of lipophages, and a CD3+ lymphocytic infiltrate involving the panniculus. This led to the diagnosis of anti-PD-1-induced acquired generalized lipodystrophy, after ruling out differential diagnoses (i.e. genetic and systemic autoimmune diseases). No corticosteroids were introduced considering the high risk of inducing severe metabolic complications, and pembrolizumab was discontinued as complete response of the melanoma was achieved. However, after 12 months of follow-up, lipodystrophy and its severe metabolic complications are still ongoing. What's already known about this topic? Anti-programmed cell death (PD)1 agents are now a standard of care in the treatment of several cancers, including melanoma. Endocrine and cutaneous immune-related adverse events (irAEs) are among the most frequent irAEs (14-30% and 30-40%, respectively) in patients treated with immune checkpoint inhibitors. What does this study add? Acquired generalized lipodystrophy can occur during anti-PD1 therapy and is associated with severe metabolic complications. With the increase in anti-PD1 prescription in several cancer types, clinicians must be aware of the whole range of irAEs that may occur.


Asunto(s)
Lipodistrofia Generalizada Congénita , Melanoma , Anticuerpos Monoclonales Humanizados , Humanos , Inhibidores de Puntos de Control Inmunológico , Melanoma/tratamiento farmacológico , Persona de Mediana Edad , Receptor de Muerte Celular Programada 1
5.
Prog Urol ; 30(8-9): 426-429, 2020.
Artículo en Francés | MEDLINE | ID: mdl-32389492

RESUMEN

For the first time, faced with a crisis with an exceptional magnitude due to the COVID-19 pandemic responsible for saturation of emergency services and intensive care units, the urolithiasis committee of the French Urology Association designed the recommendations for care and treatment of stone-forming patients and their treatment during crisis.


Asunto(s)
Infecciones por Coronavirus/epidemiología , Neumonía Viral/epidemiología , Urolitiasis/terapia , Urología/métodos , COVID-19 , Francia/epidemiología , Humanos , Pandemias , Guías de Práctica Clínica como Asunto
6.
Opt Express ; 27(6): 8871-8883, 2019 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-31052698

RESUMEN

We present experimental results obtained at a user-oriented XUV beamline implemented at the ELI Beamlines facility. The coherent XUV radiation is produced via high harmonic generation in gases in a loose focusing geometry. The beamline is designed to be driven by 1 kHz, 100 mJ, 20 fs pulses centered at a wavelength of 830 nm. Results such as XUV spectra, beam wavefront and pulse energy obtained during the beamline commissioning with a commercial 1 kHz, 5 mJ, 40 fs laser system are presented. A unique XUV spectrometer for source characterization designed to reach a very high sensitivity is described in detail, and we demonstrate a novel technique for single-shot and every-shot XUV pulse energy measurement.

7.
J Viral Hepat ; 25(10): 1132-1138, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29660206

RESUMEN

An important requirement for a state-of-the-art hepatitis B surface antigen (HBsAg) screening assay is reliable detection of mutated HBsAg. Currently, there is a striking shortage of data regarding the detection rates of in vivo HBsAg mutations for these clinically important assays. Therefore, we compared the detection rates of four commercial HBsAg screening assays using a global cohort of 1553 patients from four continents with known HBV genotypes. These samples, which represent the broadest spectrum of known and novel HBsAg major hydrophilic region (MHR) mutations to date, were analyzed for the presence of HBsAg using the Roche Elecsys® HBsAg II Qualitative, Siemens ADVIA Centaur XP HBsAg II, Abbott Architect HBsAg Qualitative II and DiaSorin Liaison® HBsAg Qualitative assays, respectively. Of the 1553 samples, 1391 samples could be sequenced; of these, 1013 (72.8%) carried at least one of the 345 currently known amino acid substitutions (distinct HBsAg mutation) in the HBsAg MHR. All 1553 patient samples were positive for HBsAg using the Elecsys® HBsAg II Qual assay, with a sensitivity (95% confidence interval) of 99.94% (99.64%-100%), followed by the Abbott Architect 99.81% (99.44%-99.96%), Siemens ADVIA 99.81% (99.44%-99.96%) and DiaSorin Liaison® 99.36% (98.82%-99.69%) assays, respectively. Our results indicate that the Elecsys® HBsAg II Qual assay exhibits the highest sensitivity among the commercial HBsAg screening assays, and demonstrate that its capacity to detect HBV infection is not compromised by HBsAg MHR mutants.


Asunto(s)
Pruebas Diagnósticas de Rutina/normas , Antígenos de Superficie de la Hepatitis B/genética , Virus de la Hepatitis B/genética , Hepatitis B/virología , Tamizaje Masivo/métodos , Estudios de Cohortes , Genotipo , Hepatitis B/diagnóstico , Antígenos de Superficie de la Hepatitis B/sangre , Virus de la Hepatitis B/inmunología , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B Crónica/diagnóstico , Hepatitis B Crónica/virología , Humanos , Inmunoensayo , Mutación , Sensibilidad y Especificidad
8.
Diabet Med ; 34(3): 426-431, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27657549

RESUMEN

AIM: It is unclear whether ketosis-prone diabetes is a specific type or a subtype of Type 2 diabetes. We aimed to describe the clinical and metabolic features of ketosis-prone diabetes in a sub-Saharan population. METHODS: We consecutively enrolled and characterized 173 people with non-autoimmune diabetes admitted for hyperglycaemic crisis at the Yaoundé Central Hospital, Cameroon. Blood samples were collected for fasting glucose, HbA1c , lipid profile and C-peptide assays with insulin resistance and secretion estimation by homeostasis model assessment. People were classified as having Type 2 diabetes (n = 124) or ketosis-prone diabetes (n = 49). Ketosis-prone diabetes was sub-classified as new-onset ketotic phase (n = 34) or non-ketotic phase (n = 15). RESULTS: Ketosis-prone diabetes was found in 28.3% of the hyperglycaemic crises. Age at diabetes diagnosis was comparable in Type 2 and ketosis-prone diabetes [48 ± 14 vs 47 ± 11 years; P = 0.13] with a similar sex distribution. Overall BMI was 27.7 ± 13.4 kg/m2 and was ≥ 25 kg/m2 in 55.8% of those taking part, however, 73.5% of those with ketosis-prone diabetes reported weight loss of > 5% at diagnosis. Blood pressure and lipid profile were comparable in both types. Ketosis-prone diabetes in the ketotic phase was characterized by lower insulin secretion and higher serum triglycerides compared with non-ketotic ketosis prone and Type 2 diabetes. Type 2 and ketosis prone diabetes in the non-ketotic phase were comparable in terms of lipid profile, blood pressure, waist-to-hip ratio, BMI and fat mass, insulin secretion and insulin resistance indices. CONCLUSIONS: Ketosis-prone diabetes is likely to be a subtype of Type 2 diabetes with the potential to develop acute insulinopenic episodes.


Asunto(s)
Diabetes Mellitus Tipo 2/diagnóstico , Cetoacidosis Diabética/diagnóstico , Hiperglucemia/prevención & control , Resistencia a la Insulina , Enfermedad Aguda , Adulto , Anciano , Camerún , Terapia Combinada , Estudios Transversales , Diabetes Mellitus Tipo 2/etnología , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/terapia , Cetoacidosis Diabética/etnología , Cetoacidosis Diabética/metabolismo , Cetoacidosis Diabética/terapia , Diagnóstico Diferencial , Femenino , Hemoglobina Glucada/análisis , Hospitales Urbanos , Humanos , Insulina/sangre , Insulina/metabolismo , Resistencia a la Insulina/etnología , Secreción de Insulina , Células Secretoras de Insulina/metabolismo , Masculino , Persona de Mediana Edad , Derivación y Consulta
9.
Prog Urol ; 27(16): 1031-1035, 2017 Dec.
Artículo en Francés | MEDLINE | ID: mdl-28869172

RESUMEN

In front of the arrival of new devices intended to simplify the removal of double J stent, it poses the problem of the knowledge of the real cost of such an ablation under the current conditions of realization. MATERIAL AND METHOD: This is a monocentric economic evaluation of cost and remuneration needed data-gathering of quotation (CCAM, GHS/SE, …), estimate of the associated costs of wear and damping of the endoscopic equipments (endoscopes, cables, …), estimate of the cost of sterilization, estimate of the associated costs to the intervention of staff (Auxiliary nurse [AS] and Nurse [IDE]) with timing of the various tasks. RESULTS: Quotation CCAM JCGE004 (48€) gives access to fixed price SE1 (73.71€ for private clinic, and 75.89€ for public institution) without hospitalization nor anaesthesia. The costs were reported to an act of single double J removal. Concerning the equipments: 4.42€HT for the fibroscopes, graspers, cable and light. The costs of sterilization were: 17.95€HT. The timed workforce's costs were: 7.61-9.51€ for AS and 9.92-10.84€ for IDE. The cost of consumable was about 1.37 €HT, by excluding the common base from the extractions (1.876€HT). The total costs in France in 2016 were thus about 47.4 to 50.496€ including all taxes. CONCLUSIONS: This estimate will be used certainly for reflection on the investments and the future studies of the economic impact of the new devices of extraction, by correlating it of course with the various maintenance contracts from each institution. LEVEL OF PROOF: 4.


Asunto(s)
Costos y Análisis de Costo , Remoción de Dispositivos/economía , Remoción de Dispositivos/instrumentación , Equipo Reutilizado , Stents , Esterilización , Catéteres Urinarios , Tecnología de Fibra Óptica , Francia , Humanos , Instalaciones Privadas
10.
Phys Rev Lett ; 115(8): 083901, 2015 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-26340189

RESUMEN

We report the first experimental demonstration of a laser-driven circularly polarized soft-x-ray laser chain. It has been achieved by seeding a 32.8 nm Kr ix plasma amplifier with a high-order harmonic beam, which has been circularly polarized using a four-reflector polarizer. Our measurements testify that the amplified radiation maintains the initial polarization of the seed pulse in good agreement with our Maxwell-Bloch modeling. The resulting fully circular soft-x-ray laser beam exhibits a Gaussian profile and yields about 10^{10} photons per shot, fulfilling the requirements for laboratory-scale photon-demanding application experiments.

11.
Lett Appl Microbiol ; 60(5): 481-90, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25619748

RESUMEN

UNLABELLED: The food safety criteria that have been incorporated in European regulation (EC) No2073/2005 (Official Journal of the European Union L, 338, 2005, 1), for Listeria monocytogenes in ready-to eat (RTE) foods, specify a maximum allowable concentration of 100 CFU g(-1) or ml(-1) . Some factors such as pH, salt and modified atmosphere packaging (MAP) are used to prevent the growth of L. monocytogenes in order to comply with the limit. Interactions between background microflora (BM) and L. monocytogenes may limit the growth of L. monocytogenes. The aim of this study was to investigate the mechanisms behind the observed inhibition by natural BM of the growth of L. monocytogenes in ready-to-eat diced poultry meat whose pH and water activity were favourable to its growth. The dynamics of L. monocytogenes and natural BM were therefore monitored in mono-culture and co-culture experiments with various combinations of contamination levels. In the absence of BM, the growth potential of L. monocytogenes depended only on the initial inoculum. With both BM and L. monocytogenes, whatever the combination of concentrations studied, the growth potentials of L. monocytogenes were lower than in a mono-culture through a partial Jameson effect. Thus, the use-by date of this product can be optimized by using models that take into account interactions with BM. SIGNIFICANCE AND IMPACT OF THE STUDY: The study of the growth of Listeria monocytogenes in a diced poultry meat, a matrix whose pH and water activity characteristics are favourable to L. monocytogenes growth, showed that it was inhibited by natural background microflora. This highlights the importance of knowing the product's composition, and in particular the natural background microflora, which can impact the use-by date.


Asunto(s)
Microbiología de Alimentos , Listeria monocytogenes/crecimiento & desarrollo , Carne/microbiología , Aves de Corral/microbiología , Animales , Técnicas de Cocultivo , Recuento de Colonia Microbiana , Inocuidad de los Alimentos , Microbiota
12.
Diabetes Obes Metab ; 16(9): 861-8, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24641271

RESUMEN

AIM: Glucagon-like peptide-1 (GLP-1) receptor agonists improve islet function and delay gastric emptying in patients with type 2 diabetes mellitus (T2DM). This meta-analysis aimed to investigate the effects of the once-daily prandial GLP-1 receptor agonist lixisenatide on postprandial plasma glucose (PPG), glucagon and insulin levels. METHODS: Six randomized, placebo-controlled studies of lixisenatide 20 µg once daily were included in this analysis: lixisenatide as monotherapy (GetGoal-Mono), as add-on to oral antidiabetic drugs (OADs; GetGoal-M, GetGoal-S) or in combination with basal insulin (GetGoal-L, GetGoal-Duo-1 and GetGoal-L-Asia). Change in 2-h PPG and glucose excursion were evaluated across six studies. Change in 2-h glucagon and postprandial insulin were evaluated across two studies. A meta-analysis was performed on least square (LS) mean estimates obtained from analysis of covariance (ANCOVA)-based linear regression. RESULTS: Lixisenatide significantly reduced 2-h PPG from baseline (LS mean difference vs. placebo: -4.9 mmol/l, p < 0.001) and glucose excursion (LS mean difference vs. placebo: -4.5 mmol/l, p < 0.001). As measured in two studies, lixisenatide also reduced postprandial glucagon (LS mean difference vs. placebo: -19.0 ng/l, p < 0.001) and insulin (LS mean difference vs. placebo: -64.8 pmol/l, p < 0.001). There was a stronger correlation between 2-h postprandial glucagon and 2-h PPG with lixisenatide than with placebo. CONCLUSIONS: Lixisenatide significantly reduced 2-h PPG and glucose excursion together with a marked reduction in postprandial glucagon and insulin; thus, lixisenatide appears to have biological effects on blood glucose that are independent of increased insulin secretion. These effects may be, in part, attributed to reduced glucagon secretion.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Péptido 1 Similar al Glucagón/agonistas , Glucagón/sangre , Hipoglucemiantes/uso terapéutico , Insulina/metabolismo , Péptidos/uso terapéutico , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Vaciamiento Gástrico/efectos de los fármacos , Glucagón/efectos de los fármacos , Glucagón/metabolismo , Hemoglobina Glucada/metabolismo , Humanos , Insulina/sangre , Secreción de Insulina , Periodo Posprandial , Ensayos Clínicos Controlados Aleatorios como Asunto
13.
Nano Lett ; 13(11): 5147-52, 2013 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-24111679

RESUMEN

Intracellular biochemical reactions are often localized in space and time, inducing gradients of enzymatic activity that may play decisive roles in determining cell's fate and functions. However, the techniques available to examine such enzymatic gradients of activity remain limited. Here, we propose a new method to engineer a spatial gradient of signaling protein concentration within Xenopus egg extracts using superparamagnetic nanoparticles. We show that, upon the application of a magnetic field, a concentration gradient of nanoparticles with a tunable length extension is established within confined egg extracts. We then conjugate the nanoparticles to RanGTP, a small G-protein controlling microtubule assembly. We found that the generation of an artificial gradient of Ran-nanoparticles modifies the spatial positioning of microtubule assemblies. Furthermore, the spatial control of the level of Ran concentration allows us to correlate the local fold increase in Ran-nanoparticle concentration with the spatial positioning of the microtubule-asters. Our assay provides a bottom-up approach to examine the minimum ingredients generating polarization and symmetry breaking within cells. More generally, these results show how magnetic nanoparticles and magnetogenetic tools can be used to control the spatiotemporal dynamics of signaling pathways.


Asunto(s)
Magnetismo , Nanopartículas , Proteínas/química , Transducción de Señal
14.
J Frailty Aging ; 13(3): 240-247, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39082768

RESUMEN

BACKGROUND: The study investigates the correlation between muscle mass and physical activity level measured objectively and subjectively in older adults who fall or are at high risk of falling. METHODS: FITNESS (Fall Interest to Target Newly Sarcopenic Society) is a multi-center (French university hospitals of Angers, Lille, Limoges and Orléans), cross-sectional, observational study of routine care within a French multidisciplinary hospital consultation. Inclusion criteria were ≥ 75 years old, living at home and consulting for fall or gait disorder. A standardized geriatric assessment, muscle mass evaluation by impedancemetry, physical activity by continuous actimetry (5 days) and Incidental and Planned Exercise Questionnaire (IPEQ) were performed at patient inclusion. RESULTS: 170 people aged 75 and over were included in the FITNESS study (mean age 82.9 ±4.7 years, women 72.9%). Muscle mass (whole body and lower limbs) correlated with active energy expenditure (AEE, ρ whole body = 0.32, p-value < 0.001; ρ lower limbs = 0.25, p-value = 0.003), but not with number of daily steps, nor with IPEQ score. Multivariate analysis of whole-body muscle mass showed a positive and significant association with AEE and albumin levels and for lower limb muscle mass, a positive association with AEE and Charlson. CONCLUSION: This study suggests that in the particular population of older adults who fall and/or are at high risk of falling, loss of muscle mass correlates with reduced physical activity. So subjects who fall or at high risk of falling constitute a special group for whom the fight against sedentary lifestyles and the maintenance of physical activity should be a dual priority.


Asunto(s)
Accidentes por Caídas , Ejercicio Físico , Evaluación Geriátrica , Humanos , Masculino , Femenino , Accidentes por Caídas/prevención & control , Accidentes por Caídas/estadística & datos numéricos , Anciano , Estudios Transversales , Anciano de 80 o más Años , Evaluación Geriátrica/métodos , Músculo Esquelético , Sarcopenia/epidemiología , Metabolismo Energético/fisiología , Factores de Riesgo , Francia/epidemiología , Encuestas y Cuestionarios
15.
J Clin Virol ; 174: 105712, 2024 10.
Artículo en Inglés | MEDLINE | ID: mdl-39047323

RESUMEN

Fourth-generation HIV immunoassays have been developed to reduce the window period of detection during seroconversion period, allowing for the detection of early and established infections. The aim of this work was to evaluate a newly developed assay, Access HIV Ag/Ab combo on the novel high throughput DxI 9000 Access Immunoassay Analyzer (Beckman Coulter, Inc.). The assay allows for simultaneous qualitative detection and differentiation of HIV-1 p24 antigen and HIV-1/2 antibodies. Assay performance was compared to two gold standard assays, the Abbott Architect HIV Ag/Ab Combo and Roche Elecsys HIV Duo, and assessed in a multicenter study, using a wide panel of samples (n > 9000, clinical samples and viral lysates) representative of genetic diversity for both antibodies and antigens, early phases of infection, negative, and cross-reacting samples. The clinical sensitivity was 100 % for clinical samples as well as for viral lysates. Data on viral lysates and early detection on seroconversion panels showed a better result with the Access assay. Analytical sensitivity showed a limit of p24 detection determined around 0.2 IU/mL. The overall specificity was 99.91 %, and no interference was found using the potentially cross-reactive samples. In conclusion, the Access HIV Ag/Ab combo assay demonstrated its ability for accurate diagnosis of chronic as well as primary HIV infections on the DxI 9000 Analyzer, despite the high level of genetic diversity of these viruses.


Asunto(s)
Anticuerpos Anti-VIH , Proteína p24 del Núcleo del VIH , Infecciones por VIH , VIH-1 , Sensibilidad y Especificidad , Humanos , Infecciones por VIH/diagnóstico , Anticuerpos Anti-VIH/sangre , Inmunoensayo/métodos , VIH-1/inmunología , VIH-1/genética , Proteína p24 del Núcleo del VIH/sangre , Proteína p24 del Núcleo del VIH/inmunología , Antígenos VIH/sangre , Antígenos VIH/inmunología , VIH-2/inmunología , VIH-2/genética , Juego de Reactivos para Diagnóstico/normas
16.
Animal ; 18 Suppl 2: 101233, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39054177

RESUMEN

Small ruminant (sheep and goat) production of meat and milk is undertaken in diverse topographical and climatic environments and the systems range from extensive to intensive. This could lead to different types of welfare compromise, which need to be managed. Implementing Precision Livestock Farming (PLF) and other new or innovative technologies could help to manage or monitor animal welfare. This paper explores such opportunities, seeking to identify promising aspects of PLF that may allow improved management of welfare for small ruminants using literature search (two reviews), workshops in nine countries (France, Greece, Ireland, Israel, Italy, Norway, Romania, Spain, and the United Kingdom) with 254 stakeholders, and panels with 52 experts. An investigation of the main welfare challenges that may affect sheep and goats across the different management systems in Europe was undertaken, followed by a prioritisation of animal welfare issues obtained in the nine countries. This suggested that disease and health issues, feed access and undernutrition/malnutrition, maternal behaviour/offspring losses, environmental stressors and issues with agonistic behavioural interactions were important welfare concerns. These welfare issues and their indicators (37 for sheep, 25 for goats) were categorised into four broad welfare indicator categories: weight loss or change in body state (BWC), behavioural change (BC), milk yield and quality (MY), and environmental indicators (Evt). In parallel, 24 potential PLF and innovative technologies (8 for BWC; 10 for BC; 4 for MY; 6 for Evt) that could be relevant to monitor these broad welfare indicator categories and provide novel approaches to manage and monitor welfare have been identified. Some technologies had the capacity to monitor more than one broad indicator. Out of the 24 technologies, only 12 were animal-based sensors, or that could monitor the animal individually. One alternative could be to incorporate a risk management approach to welfare, using aspects of environmental stress. This could provide an early warning system for the potential risks of animal welfare compromise and alert farmers to the need to implement mitigation actions.


Asunto(s)
Crianza de Animales Domésticos , Bienestar del Animal , Cabras , Animales , Crianza de Animales Domésticos/métodos , Ovinos , Europa (Continente) , Ganado
17.
Opt Express ; 21(9): 11441-7, 2013 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-23670000

RESUMEN

We present single shot nanoscale imaging using a table-top femtosecond soft X-ray laser harmonic source at a wavelength of 32 nm. We show that the phase retrieval process in coherent diffractive imaging critically depends on beam quality. Coherence and image fidelity are measured from single-shot coherent diffraction patterns of isolated nano-patterned slits. Impact of flux, wave front and coherence of the soft X-ray beam on the phase retrieval process and the image quality are discussed. After beam improvements, a final image reconstruction is presented with a spatial resolution of 78 nm (half period) in a single 20 fs laser harmonic shot.


Asunto(s)
Algoritmos , Artefactos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Nanopartículas/ultraestructura , Difracción de Rayos X/métodos
18.
Nanotechnology ; 24(43): 432002, 2013 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-24107712

RESUMEN

Metallic nanoparticles (MNPs) such as iron oxide and gold nanoparticles are interesting platforms to build theragnostic nanocarriers which combine both therapeutic and diagnostic functions within a single nanostructure. Nevertheless, their surface must be functionalized to be suitable for in vivo applications. Surface functionalization also provides binding sites for targeting ligands, and for drug loading. This review focuses on the materials and surface chemistry used to build hybrid nanocarriers that are inorganic cores functionalized with organic materials. The surface state of the MNPs largely depends on their synthesis routes, and dictates the strategies used for functionalization. Two main strategies can be found in the literature: the design of core-shell nanosystems, or embedding nanoparticles in organic materials. Emerging tendencies such as the use of clusters or alternative coating materials are also described. To present both hydrophilic and lipophilic nanosystems, we chose the doxorubicin anticancer agent as an example, as the molecule presents an affinity for both types of materials.


Asunto(s)
Nanopartículas del Metal/química , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Coloides/síntesis química , Doxorrubicina/administración & dosificación , Doxorrubicina/química , Portadores de Fármacos , Compuestos Férricos/química , Interacciones Hidrofóbicas e Hidrofílicas , Liposomas/química , Polímeros/química , Electricidad Estática , Propiedades de Superficie
19.
J Dairy Sci ; 96(9): 5591-602, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23810590

RESUMEN

The mechanisms of cellular damage that lactic acid bacteria incur during freeze-thaw processes have not been elucidated to date. Fourier transform infrared spectroscopy was used to investigate in situ the lipid phase transition behavior of the membrane of Lactobacillus delbrueckii ssp. bulgaricus CFL1 cells during the freeze-thaw process. Our objective was to relate the lipid membrane behavior to membrane integrity losses during freezing and to cell-freezing resistance. Cells were produced by using 2 different culture media: de Man, Rogosa, and Sharpe (MRS) broth (complex medium) or mild whey-based medium (minimal medium commonly used in the dairy industry), to obtain different membrane lipid compositions corresponding to different recovery rates of cell viability and functionality after freezing. The lipid membrane behavior studied by Fourier transform infrared spectroscopy was found to be different according to the cell lipid composition and cryotolerance. Freeze-resistant cells, exhibiting a higher content of unsaturated and cyclic fatty acids, presented a lower lipid phase transition temperature (Ts) during freezing (Ts=-8°C), occurring within the same temperature range as the ice nucleation, than freeze-sensitive cells (Ts=+22°C). A subzero value of lipid phase transition allowed the maintenance of the cell membrane in a relatively fluid state during freezing, thus facilitating water flux from the cell and the concomitant volume reduction following ice formation in the extracellular medium. In addition, the lipid phase transition of freeze-resistant cells occurred within a short temperature range, which could be ascribed to a reduced number of fatty acids, representing more than 80% of the total. This short lipid phase transition could be associated with a limited phenomenon of lateral phase separation and membrane permeabilization. This work highlights that membrane phase transitions occurring during freeze-thawing play a fundamental role in the cryotolerance of Lb. delbrueckii ssp. bulgaricus CFL1 cells.


Asunto(s)
Lactobacillus delbrueckii/fisiología , Lípidos de la Membrana/fisiología , Medios de Cultivo , Ácidos Grasos/análisis , Congelación , Cromatografía de Gases y Espectrometría de Masas , Lactobacillus delbrueckii/química , Lactobacillus delbrueckii/crecimiento & desarrollo , Lípidos de la Membrana/química , Espectroscopía Infrarroja por Transformada de Fourier
20.
Prog Urol ; 23(16): 1389-99, 2013 Dec.
Artículo en Francés | MEDLINE | ID: mdl-24274943

RESUMEN

The Lithiasis Committee of the French Association of Urology (CLAFU) aimed to update the current knowledge about urolithiasis. This update will be divided into four parts: 1) general considerations; 2) the management of ureteral stones; 3) the management of kidney stones; 4) metabolic assessment and medical treatment of urolithiasis. Recent technicals advances helped the urologists to improve stones management: new extracorporeal shockwave lithotripsy (ESWL) devices, new flexible ureterorenoscopes, development of laser fragmentation. ESWL, semi-rigid and flexible ureteroscopy and the percutaneous nephrolithotomy (PCNL) remain currently the main therapeutic options. The first part of this update deals with the description and classification of stones, preoperative assessment, post-operative management and clinical follow-up. Main criteria of therapeutic choices are stone location, stone composition and stone size. Stone composition is assessed with infrared spectrophotometry analysis and its hardness is correlated with U.H. density on CT scan assessment. Preoperative assessment consists in urinary cytobacteriological examine, urinary PH, blood creatininemia, hemostasis. Low-dose CT scan is recommended before urological treatment. The result of the treatment must be done 1 or 3 months later with plain abdominal film and ultrasonography. Medical management of urolithiasis will be based on stone composition, metabolic and nutritional evaluation. Treatment success is definited by absence of residual fragments. Annual follow-up is recommended and based either on plain abdominal film and ultrasonography or low-dose CT scan.


Asunto(s)
Litotripsia por Láser , Nefrolitiasis/terapia , Nefrostomía Percutánea , Ureterolitiasis/terapia , Ureteroscopía , Urología , Adulto , Congresos como Asunto , Francia , Humanos , Litotripsia por Láser/instrumentación , Litotripsia por Láser/métodos , Nefrolitiasis/diagnóstico , Nefrostomía Percutánea/instrumentación , Nefrostomía Percutánea/métodos , Guías de Práctica Clínica como Asunto , Cuidados Preoperatorios/métodos , Medición de Riesgo , Factores de Riesgo , Resultado del Tratamiento , Ureterolitiasis/diagnóstico , Ureteroscopía/instrumentación , Ureteroscopía/métodos
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