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1.
Gynecol Oncol ; 155(2): 186-191, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31519320

RESUMEN

OBJECTIVE: The AGO-OVAR16 study was designed to test the efficacy, safety, and tolerability of pazopanib maintenance after first-line chemotherapy in patients with newly diagnosed advanced ovarian cancer (AOC). METHODS: Nine hundred and forty patients with histologically confirmed AOC, International Federation of Gynecology and Obstetrics (FIGO) stage II-IV, were randomized in a 1:1 ratio to receive either 800 mg pazopanib once daily or placebo for up to 24 months, unless there was disease progression, toxicity, withdrawal of consent, or death. The primary endpoint (investigator-assessed progression-free survival [PFS]) was met and previously reported. The results of final analyses of overall survival (OS) are reported here. RESULTS: A third OS interim analysis showed futility and led to study closure and a final OS analysis after last patient last visit. At the time of the final OS analysis, 494 (89.7% of the planned 551) events had occurred. No difference was observed in OS between pazopanib and placebo. The hazard ratio (HR) was 0.960 (95% confidence interval [CI]: 0.805-1.145), and the median OS from randomization was 59.1 months in pazopanib and 64.0 months in placebo arms. For the East Asian patients, similar to the first three interim OS analyses, a numerical negative trend was observed favoring placebo (HR, 1.332; 95% CI: 0.863-2.054). Exploratory analyses showed a trend for a longer time to first subsequent anti-cancer therapy or death with pazopanib over placebo (HR, 0.829; 95% CI: 0.713-0.965), with a median estimate of 19.0 and 14.5 months, respectively. No new safety signals were observed. CONCLUSION: Although pazopanib prolonged PFS, this was not associated with improvement in median OS. CLINICAL TRIAL INFORMATION: ClinicalTrials.gov: NCT00866697.


Asunto(s)
Inhibidores de la Angiogénesis/administración & dosificación , Carcinoma Epitelial de Ovario/tratamiento farmacológico , Neoplasias Ováricas/tratamiento farmacológico , Pirimidinas/administración & dosificación , Sulfonamidas/administración & dosificación , Adulto , Anciano , Carcinoma Epitelial de Ovario/mortalidad , Supervivencia sin Enfermedad , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Indazoles , Persona de Mediana Edad , Neoplasias Ováricas/mortalidad , Calidad de Vida , Resultado del Tratamiento , Adulto Joven
2.
Br J Cancer ; 116(3): 303-309, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-28072765

RESUMEN

Backround:Patients with metastatic endometrial carcinoma have a poor prognosis and PIK3CA mutations and amplifications are common in these cancers. This study evaluated the efficacy and safety of the pure PI3K inhibitor BKM120 in advanced or recurrent endometrial carcinoma. METHODS: This phase II, multicentre, single-arm, double strata (histological low grade (LG) or high grade (HG)) open-label study enrolled patients with histologically confirmed advanced or recurrent endometrial carcinoma who had received not more than one prior chemotherapy regimen. Patients received initially BKM120 100 mg tablets once daily. Primary end points were proportion of patients free of progression at 2 months (HG strata) or at 3 months (LG strata), objective response rate (ORR), and safety. RESULTS: A total of 40 patients were enrolled, of whom 16 patients had received BKM120 at 100 mg. Because of high toxicities (cutaneous rash (54%), depressive events (47%), and anxiety (40%), the IDMC has proposed to stop recruitment at 100 mg and to continue the clinical trial with a lower dose of 60 mg per day. In addition, 24 patients (median age 67 years old) were newly enrolled (14 in the LG strata and 10 in the HG strata). Rate of nonprogression at 2 months in the HG strata was 70% and at 3 months was 60% in the LG strata. Median progression-free survival (PFS) for all patients is 4.5 months (CI 95% 2.8-6.1), and the median PFS for LG strata is 8.3 months compared with 3.8 months for the HG strata. No response was reported. At 60 mg per day, the most commonly reported treatment-related adverse events (AEs) were hyperglycaemia (58%), cognitive (31%), digestive (28%), hepatic liver functions (26%), and rash (23%). The most commonly reported treatment-related grade ⩾3 AEs were HTA (17%), hyperglycaemia (17%), and increased alanine aminotransferase (24%). Five patients (21%) stopped BKM120 for toxicity. CONCLUSIONS: The BKM120 was associated with an unfavourable safety profile and minimal antitumour activity in monotherapy in advanced or recurrent endometrial carcinoma. The clinical trial was stopped before end of recruitment for toxicity.


Asunto(s)
Aminopiridinas/uso terapéutico , Antineoplásicos/uso terapéutico , Carcinoma Endometrioide/tratamiento farmacológico , Neoplasias Endometriales/tratamiento farmacológico , Morfolinas/uso terapéutico , Anciano , Anciano de 80 o más Años , Carcinoma Endometrioide/patología , Quimioterapia Adyuvante , Progresión de la Enfermedad , Neoplasias Endometriales/patología , Femenino , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Inhibidores de las Quinasa Fosfoinosítidos-3 , Recurrencia , Resultado del Tratamiento
3.
J Evol Biol ; 29(9): 1867-72, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27272199

RESUMEN

A major cost of group-living is its inherent risk of pathogen infection. To limit this risk, many group-living animals have developed the capability to prophylactically boost their immune system in the presence of group members and/or to mount collective defences against pathogens. These two phenomena, called density-dependent prophylaxis and social immunity, respectively, are often used to explain why, in group-living species, individuals survive better in groups than in isolation. However, this survival difference may also reflect an alternative and often overlooked process: a cost of social isolation on individuals' capability to fight against infections. Here, we disentangled the effects of density-dependent prophylaxis, social immunity and stress of social isolation on the survival after pathogen exposure in group-living adults of the European earwig Forficula auricularia. By manipulating the presence of group members both before and after pathogen exposure, we demonstrated that the cost of being isolated after infection, but not the benefits of social immunity or density-dependent prophylaxis, explained the survival of females. Specifically, females kept constantly in groups or constantly isolated had higher survival rates than females that were first in groups and then isolated after infection. Our results also showed that this cost of social isolation was absent in males and that social isolation did not reduce the survival of noninfected individuals. Overall, this study gives a new perspective on the role of pathogens in social evolution, as it suggests that an apparently nonadaptive, personal immune process may promote the maintenance of group-living under pathogenic environments.


Asunto(s)
Insectos/inmunología , Aislamiento Social , Animales , Ambiente , Femenino , Infecciones , Masculino , Dinámica Poblacional , Conducta Social
4.
Occup Med (Lond) ; 66(6): 454-9, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27048296

RESUMEN

BACKGROUND: Rheumatoid arthritis (RA) causes significant impairment of physical function, and thus adversely affects patients' ability to work. AIMS: To document how often work limitations are discussed by rheumatologists and RA patients during consultations. METHODS: We conducted an observational study in a sample of French rheumatologists and in a parallel sample of patients recruited by pharmacists. We asked all rheumatologists in France practising in private practice or mixed practice (private practice and hospital) to participate in a telephone survey about their most recent consultation with an RA patient. Randomly selected pharmacists recruited RA patients to complete a questionnaire about their most recent consultation with their rheumatologist. We included patients aged 20-59, with a paid job or unemployed. We calculated the proportion of consultations including work-related discussions in both samples. RESULTS: Of the 1737 rheumatologists contacted, 153 (9%) described consultations with eligible patients. Of the 1200 pharmacists contacted, 39 (3%) recruited 81 RA patients. The proportion of consultations including work-related discussions was 50% [95% confidence interval (CI) 42-58%] in the rheumatologist sample and 52% (95% CI 41-63%) in the patient sample. The most frequent subject of discussion (88%) was physical problems related to work in both samples. CONCLUSIONS: This is the first study to document the proportion of consultations where rheumatologists and their RA patients discuss work. Both specialists and patients reported that work was discussed in one in every two consultations.


Asunto(s)
Artritis Reumatoide , Comunicación , Relaciones Médico-Paciente , Derivación y Consulta , Reumatólogos , Trabajo , Adulto , Artritis Reumatoide/complicaciones , Empleo , Femenino , Francia , Humanos , Masculino , Persona de Mediana Edad , Especialización , Encuestas y Cuestionarios , Evaluación de Capacidad de Trabajo , Adulto Joven
5.
Planta ; 241(4): 847-60, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25515193

RESUMEN

MAIN CONCLUSION: Aqueous Si limits Cu uptake by a Si-accumulating plant via physicochemical mechanisms occurring at the root level. Sufficient Si supply may alleviate Cu toxicity in Cu-contaminated soils. Little information is available on the role of silicon (Si) in copper (Cu) tolerance while Cu toxicity is widespread in crops grown on Cu-contaminated soils. A hydroponic study was set up to investigate the influence of Si on Cu tolerance in durum wheat (Triticum turgidum L.) grown in 0, 0.7, 7.0 and 30 µM Cu without and with 1.0 mM Si, and to identify the mechanisms involved in mitigation of Cu toxicity. Si supply alleviated Cu toxicity in durum wheat at 30 µM Cu, while Cu significantly increased Si concentration in roots. Root length, photosynthetic pigments concentrations, macroelements, and organic anions (malate, acetate and aconitate) in roots, were also increased. Desorption experiments, XPS analysis of the outer thin root surface (≤100 Å) and µXRF analyses showed that Si increased adsorption of Cu at the root surface as well as Cu accumulation in the epidermis while Cu was localised in the central cylinder when Si was not applied. Copper was not detected in phytoliths. This study provides evidences for Si-mediated alleviation of Cu toxicity in durum wheat. It also shows that Si supplementation to plants exposed to increasing levels of Cu in solution induces non-simultaneous changes in physiological parameters. We propose a three-step mechanism occurring mainly at the root level and limiting Cu uptake and translocation to shoots: (i) increased Cu adsorption onto the outer thin layer root surface and immobilisation in the vicinity of root epidermis, (ii) increased Cu complexation by both inorganic and organic anions such as aconitate and, (iii) limitation of translocation through an enhanced thickening of a Si-loaded endodermis.


Asunto(s)
Cobre/toxicidad , Silicio/farmacología , Triticum/efectos de los fármacos , Biomasa , Hidroponía , Fotosíntesis/efectos de los fármacos , Hojas de la Planta/química , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/crecimiento & desarrollo , Raíces de Plantas/química , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/crecimiento & desarrollo , Brotes de la Planta/química , Brotes de la Planta/efectos de los fármacos , Brotes de la Planta/crecimiento & desarrollo , Plantones/química , Plantones/efectos de los fármacos , Plantones/crecimiento & desarrollo , Triticum/química , Triticum/crecimiento & desarrollo
6.
J Evol Biol ; 28(7): 1299-308, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25975926

RESUMEN

The evolution of family life requires net fitness benefits for offspring, which are commonly assumed to mainly derive from parental care. However, an additional source of benefits for offspring is often overlooked: cooperative interactions among juvenile siblings. In this study, we examined how sibling cooperation and parental care could jointly contribute to the early evolution of family life. Specifically, we tested whether the level of food transferred among siblings (sibling cooperation) in the European earwig Forficula auricularia (1) depends on the level of maternal food provisioning (parental care) and (2) is translated into offspring survival, as well as female investment into future reproduction. We show that higher levels of sibling food transfer were associated with lower levels of maternal food provisioning, possibly reflecting a compensatory relationship between sibling cooperation and maternal care. Furthermore, the level of sibling food transfer did not influence offspring survival, but was associated with negative effects on the production of the second and terminal clutch by the tending mothers. These findings indicate that sibling cooperation could mitigate the detrimental effects on offspring survival that result from being tended by low-quality mothers. More generally, they are in line with the hypothesis that sibling cooperation is an ancestral behaviour that can be retained to compensate for insufficient levels of parental investment.


Asunto(s)
Conducta Animal/fisiología , Evolución Biológica , Insectos/fisiología , Hermanos , Animales , Tamaño de la Nidada , Conducta Alimentaria , Femenino , Conducta Materna , Ninfa , Análisis de Supervivencia
7.
Br J Cancer ; 109(10): 2507-14, 2013 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-24129243

RESUMEN

BACKGROUND: Although patients with cancer are often accompanied by a relative during breaking bad news (BBN) consultations, little is known regarding the efficacy of training programmes designed to teach residents the communication skills needed to break bad news in a triadic consultation. METHODS: Residents were randomly assigned to a 40-h dyadic and triadic communication skills training programme (n=48) or a waiting list (n=47). A simulated BBN triadic consultation was audiotaped at baseline, and after training for the training group, and 8 months after baseline for the waiting list group. Transcripts were analysed using content analysis software (LaComm). A coder determined the moment of bad news delivery and the relative's first turn of speech regarding the bad news. A generalised estimating equation was used to evaluate residents' communication skills, BBN timing, and the relative's inclusion in the consultation. RESULTS: Ninety-five residents were included. After training, the duration of the pre-delivery phase was found to be longer for the trained residents (relative risk (RR)=3.04; P<0.001). The simulated relative's first turn of speech about the bad news came more often during the pre-delivery phase (RR=6.68; P=0.008), and was more often initiated by the trained residents (RR=19.17; P<0.001). Trained residents also used more assessment (RR=1.83; P<0.001) and supportive utterances (RR=1.58; P<0.001). CONCLUSION: This study demonstrates that a training programme that focuses on the practice of dyadic and triadic communication skills can improve the communication skills of the participating residents in a BBN triadic consultation. Such a training should be included in resident curriculum.


Asunto(s)
Competencia Clínica , Internado y Residencia , Relaciones Médico-Paciente , Médicos , Revelación de la Verdad , Adulto , Competencia Clínica/normas , Comunicación , Educación , Educación Médica/métodos , Educación Médica/normas , Femenino , Humanos , Internado y Residencia/métodos , Internado y Residencia/normas , Masculino , Simulación de Paciente , Médicos/psicología , Médicos/normas , Mejoramiento de la Calidad , Adulto Joven
8.
J Evol Biol ; 26(10): 2209-20, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23981229

RESUMEN

Although inbreeding is commonly known to depress individual fitness, the severity of inbreeding depression varies considerably across species. Among the factors contributing to this variation, family interactions, life stage and sex of offspring have been proposed, but their joint influence on inbreeding depression remains poorly understood. Here, we demonstrate that these three factors jointly shape inbreeding depression in the European earwig, Forficula auricularia. Using a series of cross-breeding, split-clutch and brood size manipulation experiments conducted over two generations, we first showed that sib mating (leading to inbred offspring) did not influence the reproductive success of earwig parents. Second, the presence of tending mothers and the strength of sibling competition (i.e. brood size) did not influence the expression of inbreeding depression in the inbred offspring. By contrast, our results revealed that inbreeding dramatically depressed the reproductive success of inbred adult male offspring, but only had little effect on the reproductive success of inbred adult female offspring. Overall, this study demonstrates limited effects of family interactions on inbreeding depression in this species and emphasizes the importance of disentangling effects of sib mating early and late during development to better understand the evolution of mating systems and population dynamics.


Asunto(s)
Endogamia , Insectos/fisiología , Conducta Materna , Animales , Femenino , Estadios del Ciclo de Vida , Masculino , Conducta Sexual Animal
9.
Rev Mal Respir ; 40(1): 47-60, 2023 Jan.
Artículo en Francés | MEDLINE | ID: mdl-36470780

RESUMEN

Over recent years, High Flow Nasal Cannula (HFNC) oxygen therapy has been more and more extensively applied in numerous medical settings, and it is now carried out in invasive procedures such as pre-oxygenation before orotracheal intubation, often leading to complications. More generally, pre-oxygenation is aimed at maintaining the highest possible oxygen saturation for extended periods of time. With this in mind, HFNC seems as effective as standard oxygen delivery with regard to hematosis in patients with mild or moderate hypoxemia, and it presents the advantage of reducing the adverse events associated with intubation. That said, during pre-oxygenation of patients with severe hypoxemia, non-invasive ventilation (NIV) is probably more effective than HFNC, especially in the prevention of respiratory events. However, in patients with little or no hypoxemia undergoing risky procedures such as bronchial endoscopy, HFNC allows better oxygen saturation than standard methods. To summarize, even though NIV remains useful in unstable patients, especially in decreasing desaturation episodes, HFNC could represent a reasonable alternative in case of poor tolerance, allowing continuous oxygenation of patients requiring digestive endoscopy or trans-esophageal ultrasound.


Asunto(s)
Ventilación no Invasiva , Insuficiencia Respiratoria , Humanos , Oxígeno , Cánula/efectos adversos , Pulmón , Terapia por Inhalación de Oxígeno/métodos , Intubación Intratraqueal/efectos adversos , Hipoxia/etiología , Hipoxia/prevención & control , Ventilación no Invasiva/métodos , Insuficiencia Respiratoria/terapia
11.
Br J Cancer ; 103(2): 171-7, 2010 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-20628395

RESUMEN

BACKGROUND: This study aims to assess the efficacy of a 40-h training programme designed to teach residents the communication skills needed to break the bad news. METHODS: Residents were randomly assigned to the training programme or to a waiting list. A simulated patient breaking bad news (BBN) consultation was audiotaped at baseline and after training in the training group and 8 months after baseline in the waiting-list group. Transcripts were analysed by tagging the used communication skills with a content analysis software (LaComm) and by tagging the phases of bad news delivery: pre-delivery, delivery and post-delivery. Training effects were tested with generalised estimating equation (GEE) and multivariate analysis of variance (MANOVA). RESULTS: The trained residents (n=50) used effective communication skills more often than the untrained residents (n=48): more open questions (relative rate (RR)=5.79; P<0.001), open directive questions (RR=1.71; P=0.003) and empathy (RR=4.50; P=0.017) and less information transmission (RR=0.72; P=0.001). The pre-delivery phase was longer for the trained (1 min 53 s at baseline and 3 min 55 s after training) compared with the untrained residents (2 min 7 s at baseline and 1 min 46 s at second assessment time; P<0.001). CONCLUSION: This study shows the efficacy of training programme designed to improve residents' BBN skills. The way residents break bad news may thus be improved.


Asunto(s)
Comunicación , Educación , Internado y Residencia , Relaciones Médico-Paciente , Revelación de la Verdad , Humanos
12.
New Phytol ; 188(3): 902-6, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20723075

RESUMEN

• The quantification of silicon (Si) in plants generally requires a digestion procedure before the determination of the dissolved Si concentration by spectrometric analysis. Recent procedures produce rapid and accurate measurements, but are based on either hazardous chemicals or sophisticated instrumentation. • Here, we describe a simpler procedure using Tiron. Tiron [4,5-dihydroxy-1,3-benzene-disulfonic acid disodium salt, (HO)(2)C(6)H(2)(SO(3)Na)(2)] is currently used as a selective extractant for amorphous silica in soils. Because Si in the shoots is mostly composed of amorphous opaline silica particles (i.e. phytoliths), we tested the Tiron extraction procedure for plants. • Our results are critically discussed in relation to two other standard procedures: electrothermal vaporization determination and high-temperature lithium-metaborate digestion. • We demonstrate that Tiron extraction is an alternative method which allows the rapid, safe and accurate quantification of Si in shoots of various plants covering a wide range of Si concentrations.


Asunto(s)
Sal Disódica del Ácido 1,2-Dihidroxibenceno-3,5-Disulfónico , Helechos/química , Magnoliopsida/química , Brotes de la Planta/química , Dióxido de Silicio/análisis , Silicio/análisis , Métodos , Espectrofotometría Atómica/métodos
13.
Sci Rep ; 10(1): 19999, 2020 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-33203877

RESUMEN

Crops may take benefits from silicon (Si) uptake in soil. Plant available Si (PAS) can be affected by natural weathering processes or by anthropogenic forces such as agriculture. The soil parameters that control the pool of PAS are still poorly documented, particularly in temperate climates. In this study, we documented PAS in France, based on statistical analysis of Si extracted by CaCl2 (SiCaCl2) and topsoil characteristics from an extensive dataset. We showed that cultivation increased SiCaCl2 for soils developed on sediments, that cover 73% of France. This increase is due to liming for non-carbonated soils on sediments that are slightly acidic to acidic when non-cultivated. The analysis performed on non-cultivated soils confirmed that SiCaCl2 increased with the < 2 µm fraction and pH but only for soils with a < 2 µm fraction ranging from 50 to 325 g kg-1. This increase may be explained by the < 2 µm fraction mineralogy, i.e. nature of the clay minerals and iron oxide content. Finally, we suggest that 4% of French soils used for wheat cultivation could be deficient in SiCaCl2.

14.
Clin Nutr ; 39(6): 1900-1907, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31471163

RESUMEN

BACKGROUND & AIMS: Malnutrition affects 5-10% of elderly people living in the community. A few studies suggest that nutritional intervention may reduce health care costs. The present study included malnourished elderly patients living at home. It aimed to compare health care costs between patients that were prescribed ONS by their general practitioner and those who were not, and to assess the effect of ONS prescription on the risk of hospitalisation. METHODS: This prospective multicentre observational study included malnourished patients ≥70 years old who lived at home. Patients were defined as malnourished if they presented with one or more of the following criteria: weight loss ≥5% in 1 month, weight loss ≥10% in 6 months, BMI <21 kg/m2, albuminemia <35 g/L or Short-Form MNA ≤ 7. Their general practitioners prescribed an ONS, or not, according to their usual practice. Health care costs were recorded during a 6-month period. Other collected data were diseases, disability, self-perception of current health status, quality of life (QoL), nutritional status, appetite and compliance to ONS. A propensity score method was used to compare costs and risk of hospitalisation to adjust for potential confounding factors and control for selection bias. RESULTS: We analysed 191 patients. At baseline, the 133 patients (70%) who were prescribed ONS were more disabled (p < 0.001) and had poorer perception of their health (p = 0.02), lower QoL (p = 0.04) and lower appetite (p < 0.001) than the 58 patients (30%) who were not prescribed ONS. At 6 months, appetite had improved more in the ONS prescription group (p = 0.001). Weight change was not different between groups. Patients prescribed ONS were more frequently hospitalised (OR 2.518, 95% CI: [1.088; 5.829] hosp; p = 0.03). Analyses of adjusted populations revealed no differences in health care costs between groups. In the ONS prescription group, we identified that health care costs were lower (p = 0.042) in patients with an energy intake from ONS ≥ 500 kcal/d (1389 ± 264 €) vs. < 500 kcal/d (3502 ± 839 €). The risk of hospitalisation was reduced 3 and 5 times when the intake from ONS was ≥30 g of protein/day or ≥500 kcal/d, respectively. CONCLUSIONS: ONS prescription in malnourished elderly patients generated no extra heath care cost. High energy and protein intake from ONS was associated with a reduced risk of hospitalisation and health care costs.


Asunto(s)
Nutrición Enteral , Servicios de Atención de Salud a Domicilio , Hospitalización , Desnutrición/terapia , Estado Nutricional , Factores de Edad , Anciano , Anciano de 80 o más Años , Envejecimiento , Regulación del Apetito , Análisis Costo-Beneficio , Proteínas en la Dieta/administración & dosificación , Ingestión de Energía , Nutrición Enteral/efectos adversos , Nutrición Enteral/economía , Femenino , Francia , Costos de la Atención en Salud , Servicios de Atención de Salud a Domicilio/economía , Hospitalización/economía , Humanos , Masculino , Desnutrición/diagnóstico , Desnutrición/economía , Desnutrición/fisiopatología , Estudios Prospectivos , Calidad de Vida , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
15.
J Viral Hepat ; 16(9): 621-32, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19302336

RESUMEN

Cell entry by enveloped viruses is mediated by viral glycoproteins, and generally involves a short hydrophobic peptide (fusion peptide) that inserts into the cellular membrane. An internal hydrophobic domain within E1 (aa262-290) of hepatitis C virus (HCV) may function as a fusion peptide. Retrovirus-based HCV-pseudotyped viruses (HCVpp; genotype 1a) containing Ala or Pro substitutions at conserved amino acid positions within this putative fusion peptide were generated. Mutation of conserved residues significantly reduced efficiency of HCVpp entry into Huh-7 cells. The majority of amino acid substitutions appeared to disrupt necessary interactions between E1 and E2. For some mutants, reductions in HCVpp-associated E1 were associated with the incorporation of a high molecular weight, hyperglycosylated E2 that displayed decreased CD81-binding. Other entry-deficient mutants displayed normal E1E2 incorporation into pseudoparticles and normal CD81-binding, and therefore might affect viral fusion. One mutant (S283P) consistently displayed two- to threefold higher infectivity than did wild-type. Three mutations that decreased HCVpp infectivity also reduced levels of HCVcc infectious virus production. However, the S283P mutation had a different effect in the two systems as it did not increase production of infectious HCVcc. This comprehensive mutational analysis of the putative HCV fusion peptide provides insight into the role of E1 in its interaction with E2 and in HCV entry.


Asunto(s)
Vectores Genéticos , Hepacivirus/fisiología , Retroviridae/genética , Proteínas del Envoltorio Viral/genética , Virión/genética , Internalización del Virus , Sustitución de Aminoácidos , Antígenos CD/metabolismo , Línea Celular , Hepacivirus/genética , Humanos , Mutagénesis Sitio-Dirigida , Proteínas Mutantes/genética , Proteínas Mutantes/fisiología , Unión Proteica , Recombinación Genética , Tetraspanina 28 , Proteínas del Envoltorio Viral/metabolismo , Proteínas del Envoltorio Viral/fisiología
16.
J Evol Biol ; 22(9): 1906-13, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19682304

RESUMEN

In social animals, body size can be shaped by multiple factors, such as direct genetic effects, maternal effects, or the social environment. In ants, the body size of queens correlates with the social structure of the colony: colonies headed by a single queen (monogyne) generally produce larger queens that are able to found colonies independently, whereas colonies headed by multiple queens (polygyne) tend to produce smaller queens that stay in their natal colony or disperse with workers. We performed a cross-fostering experiment to investigate the proximate causes of queen size variation in the socially polymorphic ant Formica selysi. As expected if genetic or maternal effects influence queen size, eggs originating from monogyne colonies developed into larger queens than eggs collected from polygyne colonies, be they raised by monogyne or polygyne workers. In contrast, eggs sampled in monogyne colonies were smaller than eggs sampled in polygyne colonies. Hence, eggs from monogyne colonies are smaller but develop into larger queens than eggs from polygyne colonies, independently of the social structure of the workers caring for the brood. These results demonstrate that a genetic polymorphism or maternal effect transmitted to the eggs influences queen size, which probably affects the social structure of new colonies.


Asunto(s)
Hormigas/crecimiento & desarrollo , Tamaño Corporal , Óvulo , Conducta Social , Animales , Hormigas/genética , Femenino , Masculino , Polimorfismo Genético
17.
Br J Dermatol ; 160(1): 80-91, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18811683

RESUMEN

BACKGROUND: To date, risk assessment following topical exposure to cosmetic/dermatological formulations cannot be precisely evaluated. OBJECTIVES: To provide a tool for optimization of active permeation into/through skin and for risk assessment. METHODS: A predictive model was developed for estimating the cumulative mass of a chemical absorbed into and across the skin from a cosmetic/dermatological formulation. Account was taken of (i) the ionization state of the chemical, to correct the skin/vehicle partition coefficient; and (ii) the nature of the cosmetic/dermatological formulation. Three specific assumptions were made: firstly, steady-state transport across the skin was achieved despite application of a finite dose of chemical; secondly, vehicle effects were small relative to the precision of the prediction; and, thirdly, each formulation could be treated as an oil-in-water emulsion, in which only that fraction of the chemical in the aqueous phase was available to partition into the stratum corneum. A database of 101 ex vivo human skin experiments involving 36 chemicals was analysed. RESULTS: For 91% of the data, the difference between predicted and experimental values was less than a factor 5; when the aforementioned corrections were not used, on the other hand, only 26% of the data was well predicted. The model was successfully applied to predict skin absorption of two compounds not included in the database, for which in vitro percutaneous penetration from cosmetic vehicles have been measured. CONCLUSION: A model has been developed to predict the mass of a chemical absorbed into and through the skin from a cosmetic or dermatological formulation.


Asunto(s)
Cosméticos/farmacocinética , Absorción Cutánea , Piel/metabolismo , Administración Cutánea , Algoritmos , Cosméticos/química , Humanos , Modelos Biológicos , Valor Predictivo de las Pruebas , Piel/efectos de los fármacos
18.
Value Health ; 17(7): A587-8, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27201998
19.
Allergy ; 63(3): 292-8, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18028246

RESUMEN

BACKGROUND: Allergic rhinitis (AR) and asthma are inflammatory conditions of the airways that often occur concomitantly. This observational, cross-sectional, national study was undertaken to describe the frequency and severity of AR in asthmatic patients. The impact of AR on the quality of life and the therapeutic management of patients in everyday general medical practice were also assessed. METHODS: From April to October 2005, 1906 French general practitioners (GP) participated in the study. Each physician had to fill out a questionnaire (including the Juniper Asthma Control Questionnaire and a Rhinitis Questionnaire) for up to 10 consecutive adult asthmatic patients. The first three patients with a confirmed diagnosis of AR (Allergic Rhinitis and its Impact on Asthma classification) were asked to complete the Juniper Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ). RESULTS: A total of 14,703 patient questionnaires and 4335 auto-questionnaires were analysed. Patients presented with intermittent (45%), mild (25%), moderate (25%) and severe (4%) persistent asthma. The frequency of AR in asthmatic patients was 55.2% (CI: 95%, 54.4-56.0%). Allergic rhinitis was mild for 54% and moderate/severe for 46% of patients. The frequency and severity of AR increased with the severity of asthma (P < 0.001). Moreover, AR was associated with worse asthma control whatever be the severity of asthma (P < 0.001). The global RQLQ scores of AR patients worsened with the severity of asthma (P < 0.001). Prescription of anti-asthma treatments significantly increased with the severity of AR. The majority of AR patients (81%) were treated for rhinitis. CONCLUSIONS: This survey suggested that AR was associated with more severe asthma, more difficulty to control asthma and substantial impairment of quality of life. The high frequency of AR in asthma patients requires that these conditions should be recognized and managed by GP.


Asunto(s)
Asma/epidemiología , Medicina Familiar y Comunitaria , Rinitis Alérgica Perenne/epidemiología , Rinitis Alérgica Estacional/epidemiología , Adolescente , Adulto , Distribución por Edad , Antialérgicos/uso terapéutico , Antiasmáticos/uso terapéutico , Asma/diagnóstico , Asma/tratamiento farmacológico , Distribución de Chi-Cuadrado , Comorbilidad , Intervalos de Confianza , Estudios Transversales , Femenino , Estudios de Seguimiento , Francia/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Probabilidad , Estudios Retrospectivos , Rinitis Alérgica Perenne/diagnóstico , Rinitis Alérgica Perenne/tratamiento farmacológico , Rinitis Alérgica Estacional/diagnóstico , Rinitis Alérgica Estacional/tratamiento farmacológico , Medición de Riesgo , Índice de Severidad de la Enfermedad , Distribución por Sexo , Encuestas y Cuestionarios , Resultado del Tratamiento
20.
Diabetes Metab ; 34(5): 473-81, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18783976

RESUMEN

AIM: Several studies indicate that family functioning and parental expressiveness can influence children's glycaemic control. However, previous studies have had contradictory findings. Furthermore, no previous work has simultaneously explored the mother's and father's perception of family cohesiveness together with maternal and paternal alexithymia in relation to a child's diabetic control. In this study, we examined whether the parental perception of family cohesion and the parents' degree of alexithymia could predict their child's or adolescent's glycaemic control (severe hypoglycaemia, hospitalizations for hyperglycaemia and HbA(1c)) after adjusting for demographic variables. METHODS: The study included 45 Belgian families with at least one type 1 diabetic child aged six to 18 years (25 girls and 20 boys). Parents completed demographic questionnaires about themselves and their children. Information on type 1 diabetes in their child and the family-medical history were also collected. The number of severe-hypoglycaemic events and hospitalizations for hyperglycaemia were documented for the last 12 months, as were HbA(1c) levels over the last 16 months. Finally, family cohesiveness (FACES-III) and parental alexithymia (TAS-20) were assessed. RESULTS: Hierarchical regression analyses showed that the perception of family cohesion by mothers (P<0.05) was a predictor of the number of severe hypoglycaemic events in the last 12 months. Parents' demographic variables (marital and professional status, P<0.001) and maternal alexithymia (P<0.05) were found to be predictors of the number of hospitalizations for hyperglycaemia in the last 12 months. As for HbA(1c), only two parental demographic variables were significant predictors (marital and professional status, P<0.01 and P<0.05, respectively). CONCLUSION: The maternal perception of family cohesiveness and maternal alexithymia predict on glycaemic control in children and adolescents with diabetes.


Asunto(s)
Síntomas Afectivos/psicología , Glucemia/metabolismo , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/psicología , Relaciones Interpersonales , Padres/psicología , Adolescente , Adulto , Niño , Emociones , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Masculino , Relaciones Padres-Hijo , Percepción , Apoyo Social , Encuestas y Cuestionarios
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