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1.
Nanotechnology ; 35(33)2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38701774

RESUMEN

The realization of perovskite oxide nanostructures with controlled shape and dimensions remains a challenge. Here, we investigate the use of helium and neon focused ion beam (FIB) milling in an ion microscope to fabricate BaTiO3nanopillars of sub-500 nm in diameter starting from BaTiO3(001) single crystals. Irradiation of BaTiO3with He ions induces the formation of nanobubbles inside the material, eventually leading to surface swelling and blistering. Ne-FIB is shown to be suitable for milling without inducing surface swelling. The resulting structures are defect-free single crystal nanopillars, which are enveloped, on the top and lateral sidewalls, by a point defect-rich crystalline region and an outer Ne-rich amorphous layer. The amorphous layer can be selectively etched by dipping in diluted HF. The geometry and beam-induced damage of the milled nanopillars depend strongly on the patterning parameters and can be well controlled. Ne ion milling is shown to be an effective method to rapidly prototype BaTiO3crystalline nanostructures.

2.
J Eur Acad Dermatol Venereol ; 36(1): 144-153, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34585800

RESUMEN

BACKGROUND: Epigallocatechin-3-gallate (EGCG) has been proven effective in treating viral warts. Since anticarcinogenic as well as anti-inflammatory properties are ascribed to the substance, its use has been evaluated in the context of different dermatoses. The effect of EGCG on interface dermatitis (ID), however, has not yet been explored. OBJECTIVES: In this study, we investigated the effect of EGCG on an epidermal human in vitro model of ID. METHODS: Via immunohistochemistry, lesional skin of lichen planus patients and healthy skin were analysed concerning the intensity of interferon-associated mediators, CXCL10 and MxA. Epidermal equivalents were stained analogously upon ID-like stimulation and EGCG treatment. Monolayer keratinocytes were treated likewise and supernatants were analysed via ELISA while cells were processed for vitality assay or transcriptomic analysis. RESULTS: CXCL10 and MxA are strongly expressed in lichen planus lesions and induced in keratinocytes upon ID-like stimulation. EGCG reduces CXCL10 and MxA staining intensity in epidermis equivalents and CXCL10 secretion by keratinocytes upon stimulation. It furthermore minimizes the cytotoxic effect of the stimulus and downregulates a magnitude of typical pro-inflammatory cytokines that are crucial for the perpetuation of ID. CONCLUSIONS: We provide evidence concerning anti-inflammatory effects of EGCG within a human in vitro model of ID. The capacity to suppress mediators that are centrally involved in disease perpetuation suggests EGCG as a potential topical therapeutic in lichen planus and other autoimmune skin diseases associated with ID.


Asunto(s)
Catequina , Dermatitis , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Catequina/análogos & derivados , Catequina/farmacología , Dermatitis/tratamiento farmacológico , Humanos , Queratinocitos
3.
BMC Vet Res ; 17(1): 92, 2021 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-33639950

RESUMEN

BACKGROUND: Between February and April 2016, a slight increase in mortality was observed in a colony consisting of 400 captive Seba's short-tailed bats (Carollia perspicillata). These animals cohabited with other nocturnal animal species in a dome of a private zoo in Switzerland. RESULTS: Gross and histological analysis of two (14.3%) out of the 13 animals submitted for necropsy within this period revealed a necrosuppurative pneumonia, hepatitis, splenitis, enterocolitis, and endometritis, with abundant intralesional colonies of Gram-negative rods. Yersinia (Y.) pseudotuberculosis serotype O:1 and biotype 1 belonging to the sequence type ST90 was isolated from the affected organs in both animals. Following this diagnosis, » of the colony (99 animals) was culled and submitted for gross and histopathological analysis, and a bacterial culture selective for Yersinia spp. of lung, liver, and spleen was performed. From these 99 animals, one gravid female was tested and found to be positive for Y. pseudotuberculosis in the absence of clinical symptoms and histopathological lesions. PCR analysis of altogether three bacterial isolates for virulence factors revealed the presence of the ail gene, and one isolate was also positive for the virF and yadA plasmid genes. CONCLUSIONS: These findings suggest that Carollia perspicillata are susceptible to lethal yersiniosis but do not represent a regular reservoir for Y. pseudotuberculosis. Culling of » of the population was sufficient to limit the spread of this infection among the colony. Moreover, no infections were detected in cohabitant nocturnal animals and caretakers, indicating that the zoonotic risk in this case was low.


Asunto(s)
Quirópteros/microbiología , Infecciones por Yersinia pseudotuberculosis/veterinaria , Yersinia pseudotuberculosis/aislamiento & purificación , Animales , Animales de Zoológico/microbiología , Femenino , Masculino , Embarazo , Serogrupo , Suiza , Infecciones por Yersinia pseudotuberculosis/epidemiología
4.
Nano Lett ; 18(3): 1882-1887, 2018 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-29470089

RESUMEN

Efficient polarization of organic molecules is of extraordinary relevance when performing nuclear magnetic resonance (NMR) and imaging. Commercially available routes to dynamical nuclear polarization (DNP) work at extremely low temperatures, relying on the solidification of organic samples and thus bringing the molecules out of their ambient thermal conditions. In this work, we investigate polarization transfer from optically pumped nitrogen vacancy centers in diamond to external molecules at room temperature. This polarization transfer is described by both an extensive analytical analysis and numerical simulations based on spin bath bosonization and is supported by experimental data in excellent agreement. These results set the route to hyperpolarization of diffusive molecules in different scenarios and consequently, due to an increased signal, to high-resolution NMR.

5.
Pathologe ; 39(4): 320-327, 2018 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-29796710

RESUMEN

Founded in 1386, Heidelberg University is Germany's oldest and one of Europe's most reputable universities. As a scientific hub in Germany, Heidelberg is home to several internationally renowned medical research facilities that have an enormous demand for biomaterial samples and data-especially in the field of translational and cancer research.The main objective of the BMBF-funded project "BioMaterialBank Heidelberg" (BMBH) was the harmonization of local biobanking under the same administrative roof through the implementation of common and standardized project, data, and quality management procedures.In the very beginning, existing structures and processes of the participating biobanks in Heidelberg were identified and a common administrative structure with central representatives for IT and quality management (QM) was established to coordinate all BMBH activities.Over time, implementation of consented structures and processes took place, also revealing organizational challenges that had to be solved concerning, for example, differences in sample handling and the definition of consistent access regulations.We will discuss below these challenges as well as the opportunities of building a centralized biobank and show how issues can be resolved using the example of the BMBH.


Asunto(s)
Bancos de Muestras Biológicas , Investigación Biomédica , Europa (Continente)
6.
J Anim Physiol Anim Nutr (Berl) ; 102(2): e798-e805, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29134690

RESUMEN

According to a previous meta-analysis, adult dogs do not notably increase calcium absorption from the gastrointestinal tract when calcium intake is decreased. This results in a negative calcium balance even with a moderate calcium reduction. In this study we wanted to verify (i) whether a negative calcium balance occurs at a calcium intake equivalent to NRC (2006) (Nutrient requirements of dogs and cats, 2006, The National Academies Press, Washington, DC) minimal requirements, and if so (ii) whether the negative calcium balance will persist for up to 6 months on a low-calcium diet. After a pre-feeding period of at least 18 weeks with calcium intake slightly exceeding maintenance requirements (200 mg/kg body weight0.75 ), 12 dogs (6 Beagles, 6 Foxhound crossbreds) were fed a low-calcium diet for 28 weeks. One dog was removed from the trial for reasons unrelated to the study at week 23. Calcium intake amounted to 60 mg/kg body weight0.75 corresponding to the minimal requirement for maintenance in dogs (NRC, 2006 (Nutrient requirements of dogs and cats, 2006, The National Academies Press, Washington, DC)). Digestion trials were carried out at week 7, 14, 21 and 28 of the low calcium feeding period. At these time points, and at week 18 of the pre-trial, blood samples were taken and analysed for calcium, ionised calcium, phosphorus, parathyroid hormone, vitamin D, serum crosslaps and bone alkaline phosphatase. Apparent calcium digestibility was negative throughout the study, suggesting a negative calcium balance. There was no systematic decrease in faecal calcium excretion. Serum calcium, ionised calcium and phosphorus remained within the reference range. Serum crosslaps increased continuously from baseline to week 28 of trial, with averages increasing from 0.102 ng/ml to 0.279 ng/ml, suggesting osteoclastic activity, indicative of calcium mobilisation from the skeleton. The study supports the theory of a lack of adaptation of intestinal calcium absorption from diets with relatively low calcium content in dogs. This agrees with clinical findings in dogs eating low-calcium diet.


Asunto(s)
Calcio de la Dieta/administración & dosificación , Calcio/química , Calcio/metabolismo , Heces/química , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Perros , Femenino
7.
Unfallchirurg ; 121(8): 642-648, 2018 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-29404636

RESUMEN

BACKGROUND: Combinations of sternal and spinal fractures often occur due to high velocity accidents and are associated with a high incidence of concomitant injuries. The anterior thoracic wall is described as the fourth column of torso stability, which is why sternovertebral injuries (SVI) present a high risk of sagittal deformation of the trunk, in particular injuries of the thoracic spine. To date, no studies have been published on the frequency distribution of the involved vertebral bodies in large patient groups. OBJECTIVES: This study was intended to elaborate a frequency distribution of vertebral fractures accompanying sternal fractures (SF) and examine the risk of a vertebral fracture accompanying a SF. MATERIAL AND METHODS: A total of 48,193 cases with the main or secondary diagnosis of a SF and 897,963 cases with vertebral fractures based on routine data of German hospitals from the years 2005-2012 were evaluated. A concomitant injury to the spinal column was examined for each vertebral body and then evaluated statistically. RESULTS AND CONCLUSIONS: Of all patients with a SF 30.96% also suffered from a vertebral fracture. Of these 3.11% were SF as the main diagnosis and 60.89% the secondary diagnosis. While vertebral fractures generally occurred most frequently in the region of the thoracolumbar transition and the second cervical vertebral body, the SVI showed a further frequency peak in the range from the lower cervical spine to the middle thoracic spine. The present study was able to show a frequency distribution of accompanying vertebral body injuries in a large and representative collective in the case of SF for the first time.


Asunto(s)
Fracturas Óseas , Fracturas de la Columna Vertebral , Vértebras Torácicas , Distribución por Edad , Vértebras Cervicales/lesiones , Fracturas Óseas/epidemiología , Alemania/epidemiología , Hospitales/estadística & datos numéricos , Humanos , Fracturas de la Columna Vertebral/epidemiología , Esternón/lesiones , Vértebras Torácicas/lesiones
8.
Schweiz Arch Tierheilkd ; 160(12): 743-748, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30516477

RESUMEN

INTRODUCTION: The following case report describes the clinical and diagnostic procedure for suspected brucellosis infection in a dog. A 21 month old intact male Border Collie was presented with an enlarged right testicle and epididymis. The dog was imported to Switzerland from Germany at the age of three months, but was never abroad since then. Clinical and laboratory diagnostic investigation included bacteriology and histology. An initial serological evaluation by means of rapid slide agglutination test (RSAT) was negative. Repeated examination of the same serum by a chromatographic immunoassay (ICT) revealed a positive result. Brucella canis infection was confirmed by culture. The present case is intended to underline the importance of the suspected diagnosis of 'brucellosis' in the presence of reproductive tract problems in dogs. In addition, Brucella canis has zoonotic potential and it is imperative to comply with strict hygiene management.


INTRODUCTION: Le rapport de cas suivant décrit la procédure clinique et diagnostique en cas de suspicion d'infection par la brucellose chez un chien. Un Border Collie mâle intact de 21 mois a été présenté avec un grossissement du testicule et de l'épididyme droits. Le chien avait été importé d'Allemagne en Suisse à l'âge de trois mois, mais n'avait si non jamais été à l'étranger depuis lors. Des examens diagnostiques cliniques et de laboratoire, notamment bactériologie et histologie ont été effectués. Une première évaluation sérologique au moyen du test d'agglutination rapide sur lame (RSAT) était négative. Un examen ultérieur du même sérum par une immunoanalyse chromatographique (ICT) a révélé un résultat positif. L'infection à Brucella canis a été confirmée par culture. Le présent cas souligne l'importance du diagnostic présumé de «brucellose¼ en présence de problèmes de l>appareil reproducteur chez le chien. De plus, Brucella canis a un potentiel zoonotique et il est impératif d'appliquer des mesures d'hygiène strictes.


Asunto(s)
Brucella canis/aislamiento & purificación , Brucelosis/veterinaria , Enfermedades de los Perros/microbiología , Epididimitis/veterinaria , Orquitis/veterinaria , Animales , Brucelosis/diagnóstico , Brucelosis/microbiología , Enfermedades de los Perros/diagnóstico , Perros , Epididimitis/diagnóstico , Epididimitis/microbiología , Masculino , Orquitis/diagnóstico , Orquitis/microbiología
9.
Clin Exp Dermatol ; 42(6): 659-662, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28639716

RESUMEN

Dermatomyositis (DM) is an autoimmune disorder associated with a dysregulation of immune homeostasis of both the innate and adaptive immune system. Earlier data suggested that these two arms of the immune system interconnect in DM. In the current study, we analysed the association of autoantigen expression [adaptive system components: Mi2, transcriptional intermediary factor (TIF)1γ, small ubiquitin-like modifier 1 activating enzyme subunit (SAE)1, melanoma differentiation-associated protein (MDA)5] with markers of cellular stress (innate system components: MxA, p53) in skin and muscle (immunohistology and gene expression data, respectively). We found that distinctive self-antigens of DM were elevated in both skin and muscle tissue. In particular, TIF1γ expression was seen in autoimmune diseases including DM, but not in other inflammatory skin disorders. This upregulation was closely associated with p53 expression and type I interferon-regulated inflammation, suggesting that upregulation of autoantigens in the skin and muscle of patients with DM might be driven by cellular stress. Better understanding of these mechanisms could pave the way for new therapeutic concepts focusing on stress reduction.


Asunto(s)
Autoantígenos/metabolismo , Dermatomiositis/metabolismo , Músculo Esquelético/metabolismo , Proteínas Nucleares/metabolismo , Piel/metabolismo , Factores de Transcripción/metabolismo , Biomarcadores/metabolismo , Niño , Preescolar , Expresión Génica , Humanos , Regulación hacia Arriba
10.
Schweiz Arch Tierheilkd ; 158(6): 405-10, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27504836

RESUMEN

INTRODUCTION: Brachyspira (B.) hyodysenteriae is the causative agent of swine dysentery (SD), a severe mucohaemorrhagic diarrheal disease in pigs worldwide. So far, the antimicrobial susceptibility patterns of B. hyodysenteriae in Switzerland have not been investigated. Therefore, a panel of 30 porcine B. hyodysenteriae isolates were tested against 6 antimicrobial agents by using the VetMIC Brachy panel, a broth microdilution test. Tiamulin and valnemulin showed high antimicrobial activity inhibiting all isolates at low concentrations. The susceptibility testing of doxycycline revealed values from ≤0.25 µg/ ml (47%) to 2 µg/ml (10%). The MIC values of lincomycin ranged between ≤0.5 µg/ml (30%) and 32 µg/ml (43%). For tylosin, 57% of the isolates could not be inhibited at the highest concentration of ≥128 µg/ml. The MIC values for tylvalosin were between ≤0.25 µg/ml (10%) and 8 µg/ml (20%). These findings reveal Switzerland's favourable situation compared to other European countries. Above all, tiamulin and valnemulin are still effective antimicrobial agents and can be further used for the treatment of SD.


INTRODUCTION: Brachyspira (B.) hyodysenteriae est l'agent de la dysenterie porcine, une affection diarrhéique muco-hémorragique grave des porcs connue dans le monde entier. Jusqu'à ce jour, la sensibilité aux antibiotiques B. hyodysenteriae n'avait pas été étudiée en Suisse. C'est pour cela qu'on a examiné, au moyen du test de micro dilution VetMIC Brachy panel, un choix de 30 isolats porcins de B. hyodysenteriae quant à leur sensibilité face à 6 substances antimicrobiennes. La Tiamuline et la Valnémuline ont montré une activité antimicrobienne élevée, bloquant tous les isolats à de faibles concentrations. Les tests de sensibilité vis-à-vis de la Doxycilline ont donné des valeurs comprises entre ≤0.25 µg/ml (47%) et 2 µg/ml (10%). Les valeurs de CMI de la Lincomycine variaient entre ≤0.5 µg/ml (30%) et 32 µg/ml (43%). Avec la Tylosine, 57% des isolats n'ont pas pu être bloqués avec la concentration la plus élevée de ≥128 µg/ml. Les valeurs de CMI pour la Tylvalosine se situaient entre ≤0.25 µg/ml (10%) et 8 µg/ml (20%). Ces résultats montrent que la situation suisse est favorable en regard d'autres pays européens. La Tiamuline et la Valnémuline en particulier restent des substances antimicrobiennes efficaces qui peuvent continuer à être utiliser pour lutter contre la dysenterie porcine.


Asunto(s)
Antiinfecciosos/farmacología , Brachyspira hyodysenteriae/efectos de los fármacos , Infecciones por Bacterias Gramnegativas/veterinaria , Enfermedades de los Porcinos/microbiología , Animales , Brachyspira hyodysenteriae/aislamiento & purificación , Infecciones por Bacterias Gramnegativas/microbiología , Pruebas de Sensibilidad Microbiana , Porcinos , Suiza
11.
Schweiz Arch Tierheilkd ; 158(6): 433-42, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27504838

RESUMEN

INTRODUCTION: Antimicrobial resistance has become an important concern in veterinary medicine. The aim of this study was to describe the rate of antimicrobial resistance in common equine pathogens and to determine the occurrence of multidrug-resistant isolates. A retrospective analysis of all susceptibility testing results from bacterial pathogens cultured from horses at the University of Zurich Equine Hospital (2012-2015) was performed. Strains exhibiting resistance to 3 or more antimicrobial categories were defined as multidrug-resistant. Susceptibility results from 303 bacterial pathogens were analyzed, most commonly Escherichia coli (60/303, 20%) and Staphylococcus aureus (40/303, 13%). High rates of acquired resistance against commonly used antimicrobials were found in most of the frequently isolated equine pathogens. The highest rate of multidrug resistance was found in isolates of Acinetobacter baumannii (23/24, 96%), followed by Enterobacter cloacae complex (24/28, 86%) and Escherichia coli (48/60, 80%). Overall, 60% of Escherichia coli isolates were phenotypically ESBL-producing and 68% of Staphylococcus spp. were phenotypically methicillin-resistant. High rates of acquired antimicrobial resistance towards commonly used antibiotics are concerning and underline the importance of individual bacteriological and antimicrobial susceptibility testing to guide antimicrobial therapy. Minimizing and optimizing antimicrobial therapy in horses is needed.


INTRODUCTION: Une connaissance des bactéries pathogènes présentes localement est importante pour pouvoir mettre en œuvre dès le début un traitement antibiotique ciblé. Le but de cette étude était de décrire les agents infectieux les plus fréquents et leur évolution dans le temps chez les chevaux hospitalisés à l'hôpital vétérinaire de Zürich entre 1988 et 2014. Tous les résultats positifs de cultures ont été analysés rétrospectivement. Les isolats ont été classés sur la base de leur localisation, du diagnostic et de l'année de leur isolation. Diverses périodes ont été comparées au moyen d'un test de chi carré. Escherichia coli (299/1'723, 17%), Streptococcus equi ssp. zooepidemicus (295/1'723, 17%) et les staphylocoques coagulase positive (196/1'723, 11%) ont été dans l'ensemble les bactéries mises en évidence le plus souvent. Des bactéries anaérobes strictes ont été trouvées principalement dans les infections dentaires (18/66, 27%), les péritonites (6/43, 14%) et les infections des tissus mous (28/208, 13%). Des cultures mixtes étaient particulièrement fréquentes dans les infections cutanées et dentaires (24/55, 44% et 17/43, 40%). Les principaux germes isolés dans la plupart des systèmes d'organes étaient aussi bien Gram positifs que Gram négatifs. Pour cette raison, il conviendrait, jusqu'à ce que les résultats des cultures et des antibiogrammes soient connus, de choisir un médicament à large spectre d'action.


Asunto(s)
Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , Resistencia a Múltiples Medicamentos , Hospitales Veterinarios/estadística & datos numéricos , Animales , Farmacorresistencia Bacteriana , Caballos , Estudios Retrospectivos
12.
Pathologe ; 36 Suppl 2: 205-9, 2015 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-26391248

RESUMEN

The availability of high quality human tissue samples and access to associated histopathological and clinical data are essential for biomedical research. Therefore, it is necessary to establish quality assured tissue biobanks that provide high quality tissue samples for research purposes. This entails quality concerns referring not only to the biomaterial specimen itself but encompassing all procedures related to biobanking, including the implementation of structural components, e.g. ethical and legal guidelines, quality management documentation as well as data and project management and information technology (IT) administration. Moreover, an integral aspect of tissue biobanks is the quality assured evaluation of every tissue specimen that is stored in a tissue biobank and used for projects to guarantee high quality assured biomaterial.


Asunto(s)
Bancos de Tejidos/organización & administración , Gestión de la Calidad Total/organización & administración , Investigación Biomédica/organización & administración , Investigación Biomédica/normas , Alemania , Adhesión a Directriz , Humanos , Comunicación Interdisciplinaria , Colaboración Intersectorial , Bancos de Tejidos/normas , Gestión de la Calidad Total/normas
13.
Schweiz Arch Tierheilkd ; 157(12): 665-73, 2015 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-26891572

RESUMEN

In a representative cross-sectional study during 12 months of the years 2008/2009 in four abattoirs in Switzerland, lung and pleura lesions as well as lesions of slaughter carcasses and organs of 34 706 pigs were studied for frequency and type of macroscopic lesions. Of the 24276 examined pigs, 91.2% of the lungs, 94.4% of the heart and 95.5% of the livers showed no macroscopically visible lesions. Pigs that were produced for a label program had significantly less bronchopneumonia and pneumonia residuals, pleuritis and liver lesions due to echinococcosis. Pigs supervised by the Swiss Pig Health Service (SGD), showed significantly less bronchopneumonia and pneumonia residuals, diffuse pleuritis, pleuritis/pericarditis and milkspots compared to the non-SGD supervised farms. Thanks to the national eradication program for enzootic pneumonia (EP) and actinobacillosis, the health-status of lungs has been considerably improved and the prevalence of pleurisy decreased considerably. The results of this study indicate a good herd health in Swiss pig production.


Asunto(s)
Actinobacilosis/prevención & control , Pulmón/patología , Pleura/patología , Neumonía Porcina por Mycoplasma/prevención & control , Enfermedades de los Porcinos/patología , Enfermedades de los Porcinos/prevención & control , Mataderos , Animales , Estudios Transversales , Hígado/patología , Miocardio/patología , Porcinos , Suiza
14.
Nanotechnology ; 25(17): 175601, 2014 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-24717841

RESUMEN

Vertically aligned silicon nanowire (SiNW) arrays have been fabricated over a large area using a silver-assisted single-step electroless wet chemical etching (EWCE) method, which involves the etching of silicon wafers in aqueous hydrofluoric acid (HF) and silver nitrate (AgNO3) solution. A comprehensive systematic investigation on the influence of different parameters, such as the etching time (up to 15 h), solution temperature (10-80 °C), AgNO3 (5-200 mM) and HF (2-22 M) concentrations, and properties of the multi-crystalline silicon (mc-Si) wafers, is presented to establish a relationship of these parameters with the SiNW morphology. A linear dependence of the NW length on the etch time is obtained even at higher temperature (10-50 °C). The activation energy for the formation of SiNWs on Si(100) has been found to be equal to ∼0.51 eV . It has been shown for the first time that the surface area of the Si wafer exposed to the etching solution is an important parameter in determining the etching kinetics in the single-step process. Our results establish that single-step EWCE offers a wide range of parameters by means of which high quality vertical SiNWs can be produced in a very simple and controlled manner. A mechanism for explaining the influence of various parameters on the evolution of the NW structure is discussed. Furthermore, the SiNW arrays have extremely low reflectance (as low as <3% for Si(100) NWs and <12% for mc-Si NWs) compared to ∼35% for the polished surface in the 350-1000 nm wavelength range. The remarkably low reflection surface of SiNW arrays has great potential for use as an effective light absorber material in novel photovoltaic architectures, and other optoelectronic and photonic devices.

15.
Pathol Biol (Paris) ; 62(4): 190-2, 2014 Aug.
Artículo en Francés | MEDLINE | ID: mdl-24972456

RESUMEN

The number of Hematopoietic Stem Cell Transplantations has globally taken off in the past decade. However, this increase in transplantation activity has put in the spotlight the need to create a special transplantation-skilled population of nurses. This type of specialisation allocated solely to this activity has not existed within the French nursing community until now. In the attempt to harmonize clinical practices between different French transplantation centers, the French Society of Bone Marrow Transplantation and Cell Therapy (SFGM-TC) sets up its forth annual series of workshops which brought together practitioners from all member centers and took place in September 2013 in Lille. Here we report our results and recommendations regarding the implementation of a transplant nurse status for post-transplant follow-up care.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas/métodos , Enfermeras Clínicas , Cuidados Posoperatorios , Trasplante de Médula Ósea , Competencia Clínica , Francia , Humanos , Enfermeras Clínicas/educación
16.
Environ Microbiome ; 19(1): 10, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38291506

RESUMEN

BACKGROUND: Coastal ecosystem variability at tropical latitudes is dependent on climatic conditions. During the wet, rainy season, extreme climatic events such as cyclones, precipitation, and winds can be intense over a short period and may have a significant impact on the entire land‒sea continuum. This study focused on the effect of river runoff across the southwest coral lagoon ecosystem of Grand Terre Island of New Caledonia (South Pacific) after a cyclonic event, which is considered a pulse disturbance at our study site. The variability of coastal microbiomes, studied by the metabarcoding of V4 18S (protists) and V4-V5 16S (bacteria) rDNA genes, after the cyclone passage was associated with key environmental parameters describing the runoff impact (salinity, organic matter proxies, terrestrial rock origin metals) and compared to community structures observed during the dry season. RESULTS: Microbiome biodiversity patterns of the dry season were destructured because of the runoff impact, and land-origin taxa were observed in the coastal areas. After the rainy event, different daily community dynamics were observed locally, with specific microbial taxa explaining these variabilities. Plume dispersal modeling revealed the extent of low salinity areas up to the coral reef area (16 km offshore), but a rapid (< 6 days) recovery to typical steady conditions of the lagoon's hydrology was observed. Conversely, during the same time, some biological components (microbial communities, Chl a) and biogeochemical components (particulate nickel, terrigenous organic matter) of the ecosystem did not recover to values observed during the dry season conditions. CONCLUSION: The ecosystem resilience of subtropical ecosystems must be evaluated from a multidisciplinary, holistic perspective and over the long term. This allows evaluating the risk associated with a potential continued and long-term disequilibrium of the ecosystem, triggered by the change in the frequency and intensity of extreme climatic events in the era of planetary climatic changes.

17.
Harmful Algae ; 135: 102648, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38830713

RESUMEN

Reports of the benthic dinoflagellate Ostreopsis spp. have been increasing in the last decades, especially in temperate areas. In a context of global warming, evidences of the effects of increasing sea temperatures on its physiology and its distribution are still lacking and need to be investigated. In this study, the influence of temperature on growth, ecophysiology and toxicity was assessed for several strains of O. cf. siamensis from the Bay of Biscay (NE Atlantic) and O. cf. ovata from NW Mediterranean Sea. Cultures were acclimated to temperatures ranging from 14.5 °C to 32 °C in order to study the whole range of each strain-specific thermal niche. Acclimation was successful for temperatures ranging from 14.5 °C to 25 °C for O. cf. siamensis and from 19 °C to 32 °C for O. cf. ovata, with the highest growth rates measured at 22 °C (0.54-1.06 d-1) and 28 °C (0.52-0.75 d-1), respectively. The analysis of cellular content of pigments and lipids revealed some aspects of thermal acclimation processes in Ostreopsis cells. Specific capacities of O. cf. siamensis to cope with stress of cold temperatures were linked with the activation of a xanthophyll cycle based on diadinoxanthin. Lipids (neutral reserve lipids and polar ones) also revealed species-specific variations, with increases in cellular content noted under extreme temperature conditions. Variations in toxicity were assessed through the Artemia franciscana bioassay. For both species, a decrease in toxicity was observed when temperature dropped under the optimal temperature for growth. No PLTX-like compounds were detected in O. cf. siamensis strains. Thus, the main part of the lethal effect observed on A. franciscana was dependent on currently unknown compounds. From a multiclonal approach, this work allowed for defining specificities in the thermal niche and acclimation strategies of O. cf. siamensis and O. cf. ovata towards temperature. Potential impacts of climate change on the toxic risk associated with Ostreopsis blooms in both NW Mediterranean Sea and NE Atlantic coast is further discussed, taking into account variations in the geographic distribution, growth abilities and toxicity of each species.


Asunto(s)
Dinoflagelados , Calentamiento Global , Temperatura , Dinoflagelados/fisiología , Dinoflagelados/crecimiento & desarrollo , Mar Mediterráneo , Floraciones de Algas Nocivas , Animales , Aclimatación , Océanos y Mares
18.
APL Bioeng ; 8(2): 026102, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38633836

RESUMEN

The sensing of left ventricular (LV) activity is fundamental in the diagnosis and monitoring of cardiovascular health in high-risk patients after cardiac surgery to achieve better short- and long-term outcome. Conventional approaches rely on noninvasive measurements even if, in the latest years, invasive microelectromechanical systems (MEMS) sensors have emerged as a valuable approach for precise and continuous monitoring of cardiac activity. The main challenges in designing cardiac MEMS sensors are represented by miniaturization, biocompatibility, and long-term stability. Here, we present a MEMS piezoresistive cardiac sensor capable of continuous monitoring of LV activity over time following epicardial implantation with a pericardial patch graft in adult minipigs. In acute and chronic scenarios, the sensor was able to compute heart rate with a root mean square error lower than 2 BPM. Early after up to 1 month of implantation, the device was able to record the heart activity during the most important phases of the cardiac cycle (systole and diastole peaks). The sensor signal waveform, in addition, closely reflected the typical waveforms of pressure signal obtained via intraventricular catheters, offering a safer alternative to heart catheterization. Furthermore, histological analysis of the LV implantation site following sensor retrieval revealed no evidence of myocardial fibrosis. Our results suggest that the epicardial LV implantation of an MEMS sensor is a suitable and reliable approach for direct continuous monitoring of cardiac activity. This work envisions the use of this sensor as a cardiac sensing device in closed-loop applications for patients undergoing heart surgery.

19.
J Appl Microbiol ; 114(6): 1702-12, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23480553

RESUMEN

AIMS: Exopolysaccharides (EPS) are industrially valuable molecules with numerous useful properties. This study describes the techniques used for the identification of a novel Vibrio bacterium and preliminary characterization of its EPS. METHODS AND RESULTS: Bioprospection in marine intertidal areas of New Caledonia followed by screening for EPS producing brought to selection of the isolate NC470. Phylogenetic analysis (biochemical tests, gene sequencing and DNA-DNA relatedness) permitted to identify NC470 as a new member of the Vibrio genus. The EPS was produced in batch fermentation, purified using the ultrafiltration process and analysed by colorimetry, Fourier Transform Infrared spectroscopy, gas chromatography, Nuclear Magnetic Resonance and HPLC-size exclusion chromatography. This EPS exhibits a high N-acetyl-hexosamines and uronic acid content with a low amount of neutral sugar. The molecular mass was 672 × 10(3)  Da. These data are relevant for possible technological exploitation. CONCLUSIONS: We propose the name Vibrio neocaledonicus sp. nov for this isolate NC470, producing an EPS with an unusual sugar composition. Comparison with other known polymers permitted to select applications for this polymer. SIGNIFICANCE AND IMPACT OF THE STUDY: This study contributes to evaluate the marine biodiversity of New Caledonia. It also highlights the biotechnological potential of New Caledonia marine bacteria.


Asunto(s)
Polisacáridos Bacterianos/metabolismo , Vibrio/metabolismo , Carbohidratos/análisis , Hexosaminas/análisis , Nueva Caledonia , Filogenia , Polisacáridos Bacterianos/química , Ácidos Urónicos/análisis , Vibrio/clasificación , Vibrio/genética
20.
Pathol Biol (Paris) ; 61(4): 160-3, 2013 Aug.
Artículo en Francés | MEDLINE | ID: mdl-24011958

RESUMEN

OBJECTIVE: To set up the minimal conditions necessary to ensure that the social and familial network of the patient is preserved during the hospital stay for allogeneic hematopoïetic stem cell transplantation. MATERIAL AND METHODS: A national survey was conducted to increase knowledge about the conditions of hospital stay of adult and pediatric stem cell recipients. Then a multidisciplinary panel of health workers including doctors and nurses met to establish recommendations for maintaining the social and familial relationships optimally during the HSCT procedure. RESULTS: Practices and policies are very heterogeneous among the transplant centers. No consensus has been established and the literature data are scarce. The panel has thus established a list of recommendations to maintain optimal relationships between the patient and his relatives and friends during the hospital stay. The objective is to ensure a better acceptation of the isolation conditions and to facilitate the return home after D30. CONCLUSION: Since there is no established scientific background for drastic isolation conditions, a multi-disciplinary approach in relationship with patients associations should allow softening of the procedures without impairing the quality of care.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas/normas , Tiempo de Internación , Apoyo Social , Adulto , Factores de Edad , Niño , Consenso , Recolección de Datos , Familia , Francia/epidemiología , Conocimientos, Actitudes y Práctica en Salud , Trasplante de Células Madre Hematopoyéticas/psicología , Trasplante de Células Madre Hematopoyéticas/estadística & datos numéricos , Humanos , Tiempo de Internación/estadística & datos numéricos , Trasplante Homólogo , Visitas a Pacientes/estadística & datos numéricos
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