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1.
Phys Rev Lett ; 129(3): 034502, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35905359

RESUMEN

Processes leading to anomalous fluctuations in turbulent flows, referred to as intermittency, are still challenging. We consider cascade trajectories through scales as realizations of a stochastic Langevin process for which multiplicative noise is an intrinsic feature of the turbulent state. The trajectories are conditioned on their entropy exchange. Such selected trajectories concentrate around an optimal path, called instanton, which is the minimum of an effective action. The action is derived from the Langevin equation, estimated from measured data. In particular instantons with negative entropy pinpoint the trajectories responsible for the emergence of non-Gaussian statistics at small scales.

2.
Porcine Health Manag ; 7(1): 6, 2021 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-33397484

RESUMEN

In the last two decades, in France, Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) stabilization protocols have been implemented using mass vaccination with a modified live vaccine (MLV), herd closure and biosecurity measures. Efficient surveillance for PRRSV is essential for generating evidence of absence of viral replication and transmission in pigs. The use of processing fluid (PF) was first described in 2018 in the United States and was demonstrated to provide a higher herd-level sensitivity compared with blood samples (BS) for PRRSV monitoring. In the meantime, data on vertical transmission of MLV viruses are rare even as it is a major concern. Therefore, veterinarians usually wait for several weeks after a sow mass vaccination before starting a stability monitoring. This clinical study was conducted in a PRRSV-stable commercial 1000-sow breed-to-wean farm. This farm suffered from a PRRS outbreak in January 2018. After implementing a stabilisation protocol, this farm was controlled as stable for more than 9 months before the beginning of the study. PF and BS at weaning were collected in four consecutive batches born after a booster sow mass MLV vaccination. We failed to detect PRRSV by qPCR on PF and BS collected in a positive-stable breeding herd after vaccination with ReproCyc® PRRS EU (Boehringer Ingelheim, Ingelheim, Germany).

4.
Rev Mal Respir ; 33(9): 817-823, 2016 Nov.
Artículo en Francés | MEDLINE | ID: mdl-27257103

RESUMEN

Erlotinib can be prescribed in the treatment of locally advanced or metastatic non-small lung cancer cell (NSCLC) after failure of at least one prior chemotherapy regimen on the basis of the BR-21 study. Several publications have recently questioned these results. The metabolic imaging of solid tumours by positron emission tomography is a research field that could help customize the treatment of NSCLC and so complement the treatment approaches allowed by genetic analyses. This strategy is part of an innovative "early metabolic look" approach. The primary objective of this study is to determine if metabolic progression observed between the 7th and 14th day after initiation of treatment with erlotinib by 3'-Deoxy-3'-[18F]-Fluorothymidine PET in patients with EGFR naive NSCLC is predictive for morphological progression after 6 to 8 weeks of treatment. A health economic analysis will be conducted. This study is particularly innovative because it begins the exploration of the era of metabolic evaluation of therapeutic response in NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Monitoreo de Drogas/métodos , Clorhidrato de Erlotinib/uso terapéutico , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/tratamiento farmacológico , Tomografía de Emisión de Positrones , Biomarcadores Farmacológicos/análisis , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Clorhidrato de Erlotinib/farmacocinética , Femenino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Masculino , Medicina de Precisión/métodos , Valor Predictivo de las Pruebas , Proyectos de Investigación , Resultado del Tratamiento
5.
Phys Rev Lett ; 114(10): 101301, 2015 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-25815919

RESUMEN

We report the results of a joint analysis of data from BICEP2/Keck Array and Planck. BICEP2 and Keck Array have observed the same approximately 400 deg^{2} patch of sky centered on RA 0 h, Dec. -57.5°. The combined maps reach a depth of 57 nK deg in Stokes Q and U in a band centered at 150 GHz. Planck has observed the full sky in polarization at seven frequencies from 30 to 353 GHz, but much less deeply in any given region (1.2 µK deg in Q and U at 143 GHz). We detect 150×353 cross-correlation in B modes at high significance. We fit the single- and cross-frequency power spectra at frequencies ≥150 GHz to a lensed-ΛCDM model that includes dust and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r), using a prior on the frequency spectral behavior of polarized dust emission from previous Planck analysis of other regions of the sky. We find strong evidence for dust and no statistically significant evidence for tensor modes. We probe various model variations and extensions, including adding a synchrotron component in combination with lower frequency data, and find that these make little difference to the r constraint. Finally, we present an alternative analysis which is similar to a map-based cleaning of the dust contribution, and show that this gives similar constraints. The final result is expressed as a likelihood curve for r, and yields an upper limit r_{0.05}<0.12 at 95% confidence. Marginalizing over dust and r, lensing B modes are detected at 7.0σ significance.

6.
Int J Paleopathol ; 3(3): 150-157, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29539449

RESUMEN

Pathoecology provides unique frameworks for understanding disease transmission in ancient populations. Analyses of Old and New World archaeological samples contribute empirically to our understanding of parasite infections. Combining archaeological and anthropological data, we gain insights about health, disease, and the way ancient people lived and interacted with each other and with their environments. Here we present Old and New World parasite evidence, emphasizing how such information reflects the different ways ancient populations exploited diverse environments and became infected with zoonotic parasites. It is clear that the most common intestinal helminths (worm endoparasites) were already infecting ancient inhabitants of the New World prior to the European conquest, although not so intensely as in ancient Europe. The first paleoepidemiological transition from hunting-gathering to agriculture did not change the zoonotic infection pattern of people in the Americas. However, the same transition in Europe resulted in increased zoonotic parasitism with parasites from domestic animals. Therefore, there is a demonstrable difference in the impact of the first paleoepidemiologic transition in the Americas compared to Europe.

7.
J Parasitol ; 98(6): 1273-5, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22924925

RESUMEN

For the first time in the study of ancient parasites, analyses were carried out on samples taken from a First World War settlement in France (Geispolsheim, region of Alsace). Microscopic examination of sediment samples revealed the presence of 3 common human parasites, i.e., Trichuris trichiura , Ascaris lumbricoides , and Taenia sp. A review of paleoparasitological studies in Europe shows that these 3 parasites have infected humanity for centuries. Despite this recurrence, literature shows that knowledge regarding many helminths was limited, and their life cycles were only relatively recently elucidated. Finally, the present study provides additional information about the health of the German soldiers and the sanitary conditions in the trenches during the first modern world conflict.


Asunto(s)
Ascariasis/historia , Parasitosis Intestinales/historia , Personal Militar/historia , Teniasis/historia , Cuartos de Baño/historia , Tricuriasis/historia , Primera Guerra Mundial , Animales , Ascaris lumbricoides/aislamiento & purificación , Francia , Alemania , Historia del Siglo XX , Humanos , Taenia/aislamiento & purificación , Trichuris/aislamiento & purificación
8.
Biomaterials ; 32(31): 7999-8009, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21788070

RESUMEN

The aim of this work was to develop a new microparticulate system able to form a complex with radionuclides with a high yield of purity for diagnostic or therapeutic applications. Owing to its properties potato starch was chosen as starting material and modified by oxidization and coupling of a ligand (polyamine) enabling modified starch to chelate radionuclides. The choice of suitable experiments was based on a combination of a Rechtschaffner experimental design and a surface response design to determine the influence of experimental parameters and to optimize the final product. Starch-based microparticle formulations from the experimental plans were compared and characterized through particle size analysis, scanning electron microscopy, elemental analysis and, for the most promising formulations, by in vitro labeling stability studies and determination of free polyamine content or in vivo imaging studies. The mechanism of starch-based microparticle degradation was identified by means of size measurements. The results of the Rechtschaffner design showed the positive qualitative effect of the temperature and the duration of coupling reaction whereas surface response analysis clearly showed that, by increasing the oxidization level and starch concentration, the nitrogen content in the final product is increased. In vitro and in vivo characterization led to identification of the best formulation. With a size around 30 µm, high radiochemical purity (over 95%) and a high signal-to-noise ratio (over 600), the new starch-based microparticulate system could be prepared as ready-to-use kits and sterilized without modification of its characteristics, and thus meet the requirement for in vivo diagnostic and therapeutic applications.


Asunto(s)
Microesferas , Medicina Nuclear/métodos , Almidón/uso terapéutico , Análisis de Varianza , Animales , Cadaverina/metabolismo , Cromatografía Líquida de Alta Presión , Masculino , Oxidación-Reducción , Tamaño de la Partícula , Ratas , Ratas Wistar , Reproducibilidad de los Resultados , Coloración y Etiquetado , Almidón/química , Almidón/ultraestructura , Esterilización , Estrés Mecánico , Propiedades de Superficie
10.
Virchows Arch ; 453(4): 377-86, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18795323

RESUMEN

This article describes the potential interest in physical and forensic anthropology of the microscopic analysis of residues of putrefaction fluid, a calcified deposit frequently found associated with bone rests. Its sampling and analysis seem straightforward and relatively reproducible. Samples came from archeological material (Monterenzio Vecchia, an Etruscan necropolis from the north of Italy dated between the fifth and third century B.C.; body rests of Agnès Sorel, royal mistress died in 1450 A.D.; skull and grave of French King Louis the XI and Charlotte of Savoy dated from 1483 A.D.). All samples were studied by direct optical microscope and scanning electron microscopy. Many cytological, histological, and elemental analysis were possible, producing precious data for the identification of these remains and, in some cases, the cause of death.


Asunto(s)
Antropología Forense/métodos , Paleopatología/métodos , Cambios Post Mortem , Embalsamiento/historia , Personajes , Francia , Historia del Siglo XV , Historia Antigua , Humanos , Italia , Plomo/química , Microscopía/métodos , Microscopía Electrónica de Rastreo/métodos
11.
J Radiol ; 87(3): 307-10, 2006 Mar.
Artículo en Francés | MEDLINE | ID: mdl-16550115

RESUMEN

Atypical ductal hyperplasia (ADH) of the breast is a difficult histologic diagnosis. It is usually found, but not always, on clusters of microcalcifications. The subsequent risk of breast carcinoma is 4 to 5 times more important and the carcinoma can arise in the same breast or in the contralateral breast. Diagnosis can be establish on core needle biopsy with Mammotome 11G. The risk of under-estimation (ductal carcinoma in situ or invasive carcinoma) is about 20%. This risk is drastically decreased if the target (the calcifications) is completely removed by the Mammotome. This study includes 62 cases of ADH found on 633 calcifications biopsied by Mammotome 11G. In 31 cases, surgery was performed and ADH was confirmed in 25 cases (6 cases was under-estimated). In the other 31 cases, all calcifications were removed, there was no other risk factor and follow-up was suggested. Like after surgery, yearly bilateral mammography during about 20 years is recommended. In this last group, there was no false-negative result, median follow-up: 35,5 months (22-62).


Asunto(s)
Biopsia con Aguja/instrumentación , Enfermedades de la Mama/patología , Enfermedades de la Mama/cirugía , Mama/patología , Mama/cirugía , Calcinosis/patología , Calcinosis/cirugía , Adulto , Anciano , Diseño de Equipo , Femenino , Humanos , Hiperplasia , Persona de Mediana Edad
12.
Bull Soc Pathol Exot ; 99(1): 53-7, 2006 Mar.
Artículo en Francés | MEDLINE | ID: mdl-16568686

RESUMEN

Paleoparasitology in the Old World has mainly concerned the study of latrine sediments and coprolites collected from mummified bodies or archaeological strata, mostly preserved by natural conditions. For the first time, different unusual archaeological samples were studied to look for the eggs of helminths parasites (embalming reject jar, canopic package, shroud). Now, samples of organic matter have been successfully processed in order to extract helminths eggs, following the protocol of BOUCHET 2001 (4). Helminth eggs are frequently preserved in the late Quaternary archaeological contexts because of their hard-wearing chitin shell. Six types of eggs were revealed (Schistosoma mansoni, Schistosoma haematobium, Taenia, Enterobius vermicularis, Ascaris lumbricoides and Trichuris trichiura). This study allows to enlarge the Palaeoparasitological research with material never exploited. Moreover, if we take into account identified parasite and geography, it's possible to enlarge the debate to parasite spatio-temporal migration. Considering the particular context of samples preservation, it's interesting to observe an exceptional conservation of parasitological sign related to excellent taphonomic condition (aridity anaeroby, rapid interruption of thanatomorphosis, natural "mummification").


Asunto(s)
Helmintos , Paleontología , Parasitología , Animales , Egipto , Sudán
13.
J Radiol ; 85(12 Pt 2): 2111-22, 2004 Dec.
Artículo en Francés | MEDLINE | ID: mdl-15692428

RESUMEN

At screening mammography, lesions must be assigned to BI-RADS classification. Category 3 is used for nonpalpable probably benign lesions. This category is defined either by a subset of lesions that are so likely to be benign that follow-up is a reasonable alternative to immediate biopsy, or by a less than 2% malignancy rate for American BI-RADS, or than 5% for French ANAES. The initial work-up to analyze the lesion must be complete, not only with four screening standard views but with magnification views and sonography if necessary. The risk of malignancy is very low and the pronostic factors are the same as in screening detected carcinomas.


Asunto(s)
Enfermedades de la Mama/diagnóstico por imagen , Neoplasias de la Mama/diagnóstico por imagen , Calcinosis/diagnóstico por imagen , Mamografía , Enfermedades de la Mama/clasificación , Neoplasias de la Mama/clasificación , Calcinosis/clasificación , Femenino , Humanos
14.
J Parasitol ; 89(5): 1073-6, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14627164

RESUMEN

Dioctophymidae eggs were found in human coprolites dated from 3,384 to 3,370 BC from the site Arbon-Bleiche 3, Switzerland. This is the first record of dioctophymiasis in archaeological material. The important percentage of this disease in the studied coprolites raises the question of a higher prevalence during the Neolithic than at present.


Asunto(s)
Dioctophymatoidea/aislamiento & purificación , Infecciones por Enoplida/historia , Heces/parasitología , Fósiles , Animales , Historia Antigua , Humanos , Suiza
15.
J Radiol ; 83(9 Pt 1): 1063-71, 2002 Sep.
Artículo en Francés | MEDLINE | ID: mdl-12223915

RESUMEN

PURPOSE: To assess the value of percutaneous vacuum-assisted core biopsy to improve the diagnosis of non palpable mammographic abnormalities. MATERIALS AND METHODS: A total of 252 core biopsies using an 11G Mammotome((R))were performed in 249 patients. Stereotactic localization was performed in the prone position on a dedicated digital Fischer table. RESULTS: Fifty-one, or 25%, of 200 clusters of microcalcifications corresponded to carcinomas: 126 benign lesions, 23 atypical hyperplasia and LCIS, 31 DCIS, 15 invasive ductal carcinomas, and 4 false negative biopsies. In these 4 last cases, surgery was performed because radiographs of the core biopsy showed no microcalcifications; carcinoma was confirmed at histology of the surgical specimen. Using the BI-RADS system, 7 lesions were category 3, 175 lesions were category 4, and 18 lesions were category 5. From a total of 52 masses, 31 were benign lesions, 2 were borderline lesions, and 19 were invasive carcinomas. From these, 5 lesions were category 3, 31 were category 4, and 16 were category 5. Diagnostic surgical biopsy was avoided in 161 cases (63%), in 152 cases for benign lesions including 151 lesions classified as category 4 lesions and in 9 cases for multifocal or recurrent malignant lesions. CONCLUSION: When technical pitfalls are avoided and when presence of microcalcifications in the core biopsy sample is verified, vacuum assisted core biopsy with Mammotome((R)) 11G provides accurate diagnosis of non-palpable mammographic abnormalities.


Asunto(s)
Biopsia con Aguja/métodos , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Calcinosis/diagnóstico por imagen , Calcinosis/patología , Mamografía/métodos , Radiografía Intervencional/métodos , Técnicas Estereotáxicas , Succión/métodos , Biopsia con Aguja/instrumentación , Biopsia con Aguja/normas , Neoplasias de la Mama/clasificación , Neoplasias de la Mama/cirugía , Calcinosis/clasificación , Calcinosis/cirugía , Reacciones Falso Negativas , Femenino , Humanos , Mamografía/instrumentación , Mamografía/normas , Estadificación de Neoplasias/instrumentación , Estadificación de Neoplasias/métodos , Estadificación de Neoplasias/normas , Selección de Paciente , Radiografía Intervencional/instrumentación , Radiografía Intervencional/normas , Sensibilidad y Especificidad , Técnicas Estereotáxicas/instrumentación , Técnicas Estereotáxicas/normas , Succión/instrumentación , Succión/normas , Vacio
16.
J Parasitol ; 88(2): 404-5, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12054021

RESUMEN

Schistosoma mansoni eggs were found in a latrine dated AD 1450-1550 in Montbéliard, France. This is the first record of intestinal schistosomiasis in archaeological material. Because the parasite has an African origin, its presence in Europe at that time may be due to African slaves. However, intestinal schistosomiasis has never been established in Europe.


Asunto(s)
Schistosoma mansoni/aislamiento & purificación , Esquistosomiasis mansoni/historia , Cuartos de Baño/historia , Animales , Arqueología , Heces/parasitología , Francia , Historia del Siglo XV , Historia del Siglo XVI , Humanos , Esquistosomiasis mansoni/parasitología
17.
J Parasitol ; 88(6): 1266-7, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12537127

RESUMEN

Until now, Pthirus pubis infestation in ancient human populations had only been recorded in the Old World. We found crab lice on South American mummified bodies from the Atacama Desert region. Crab louse eggs were found attached to the pubic hairs of a 2,000-yr-old Chilean mummy. Well-preserved adults were found in sediment and clothing from a Peruvian mummy dated 1,000 yr ago. Paleoparasitological evidence expands the knowledge of the distribution of this ectoparasite in ancient populations. As with many other parasites, pubic lice recorded in Andean populations show the antiquity of this parasite in the New World. It is likely that P. pubis entered the continent with early human migration to the New World.


Asunto(s)
Infestaciones por Piojos/historia , Momias/parasitología , Phthirus/clasificación , Animales , Chile , Historia Antigua , Humanos , Paleopatología , Perú
18.
Int J Parasitol ; 31(10): 1101-6, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11429174

RESUMEN

On the Middle-Age site of Namur (Belgium) the analysis of coprolites revealed the presence of many well-preserved Ascaris eggs. Following rehydratation of the coprolite samples, 104 eggs were collected and extracted with an ultrasonication and phenol-chloroform based method. Three overlapping fragments of the 18S rRNA gene and one fragment of the cytochrome b gene have been reproducibly amplified, cloned and sequenced. The analysis of these sequences confirms the identification of the eggs as coming from Ascaris. Our study reveals that coprolites can be an interesting source of parasites that can be readily identified using molecular approaches. The study of ancient DNA from helminth parasites is of interest as it may answer long-standing questions in the history of infectious diseases and gives a possibility to compare these ancient sequences with those of modern populations.


Asunto(s)
Ascaris/genética , ADN de Helmintos/aislamiento & purificación , Fósiles , Animales , Secuencia de Bases , Bélgica , Grupo Citocromo b/química , Grupo Citocromo b/genética , ADN de Helmintos/química , ADN de Helmintos/genética , Heces/parasitología , Datos de Secuencia Molecular , Paleopatología/métodos , Reacción en Cadena de la Polimerasa , ARN Ribosómico 18S/química , ARN Ribosómico 18S/genética , ARN Ribosómico 18S/aislamiento & purificación , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido Nucleico
19.
C R Acad Sci III ; 324(2): 123-7, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11280043

RESUMEN

Bothriocephalid (Diphyllobothrium pacificum) and Ascarid (Ascaris lumbricoides) eggs have been identified in a sample taken in the abdominal cavity of a child skeleton found in Zeto Point (ADK-011), an archaeological site on Adak Island in the Central Aleutian Islands (Alaska).


Asunto(s)
Huesos/parasitología , Cestodos/aislamiento & purificación , Abdomen/parasitología , Alaska , Animales , Arqueología , Niño , Femenino , Humanos , Prácticas Mortuorias , Óvulo , Paleontología , Esqueleto
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