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1.
Cereb Cortex ; 33(9): 5082-5096, 2023 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-36288912

RESUMEN

Advances in Magnetic Resonance Imaging hardware and methodologies allow for promoting the cortical morphometry with submillimeter spatial resolution. In this paper, we generated 3D self-enhanced high-resolution (HR) MRI imaging, by adapting 1 deep learning architecture, and 3 standard pipelines, FreeSurfer, MaCRUISE, and BrainSuite, have been collectively employed to evaluate the cortical thickness. We systematically investigated the differences in cortical thickness estimation for MRI sequences at multiresolution homologously originated from the native image. It has been revealed that there systematically exhibited the preferences in determining both inner and outer cortical surfaces at higher resolution, yielding most deeper cortical surface placements toward GM/WM or GM/CSF boundaries, which directs a consistent reduction tendency of mean cortical thickness estimation; on the contrary, the lower resolution data will most probably provide a more coarse and rough evaluation in cortical surface reconstruction, resulting in a relatively thicker estimation. Although the differences of cortical thickness estimation at the diverse spatial resolution varied with one another, almost all led to roughly one-sixth to one-fifth significant reduction across the entire brain at the HR, independent to the pipelines we applied, which emphasizes on generally coherent improved accuracy in a data-independent manner and endeavors to cost-efficiency with quantitative opportunities.


Asunto(s)
Encéfalo , Imagen por Resonancia Magnética , Imagen por Resonancia Magnética/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Corteza Cerebral
2.
Eur Arch Otorhinolaryngol ; 281(2): 757-766, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37695364

RESUMEN

PURPOSE: Olfactory identification disorder is considered a promising early biomarker of Alzheimer's disease (AD). The QUICK TODA2 can be used as a short olfactory screening tool specific for French AD patients. The selection of AD specific odorants and the design of this screening were the main objectives of this twofold study. METHODS: In study 1, the TODA2 olfactory test was administered to 43 mild-AD patients and 45 healthy controls (HC) in five memory centres in France. The selection of AD specific odorants was based on the differences in the proportion of correct answers and in the threshold means between AD and HC groups. In study 2, another set of 19 mild-AD patient were included at the memory centre of Nice Hospital. All participants completed the olfactory assessment pipeline including the QUICK TODA2, TODA2 and Sniffin' Sticks Identification sub-Test (SST-i). The individual scores of the three tests were correlated. RESULTS: In study 1, ten TODA2 odorants could significantly differentiate AD participants from controls. We selected the six most AD-sensitive items to design the QUICK TODA2. In study 2, we reported strong significant correlations between QUICK TODA2 and TODA2 (ρ(17) = 0.68, p = 0.001**), SST-i and QUICK TODA2 (ρ(17) = 0.65, p = 0.002**), SST-i and TODA2 (ρ(17) = 0.57, p = 0.01*). CONCLUSION:  QUICK TODA2 is a 5-min non-invasive olfactory AD screening tool dedicated to French culture. Its results converge with those of longer, validated olfactory tests. It could be used as a quick screening tool in the general daily practice before an extensive assessment in memory centres.


Asunto(s)
Enfermedad de Alzheimer , Trastornos del Olfato , Humanos , Trastornos del Olfato/diagnóstico , Enfermedad de Alzheimer/diagnóstico , Olfato , Odorantes , Biomarcadores
3.
Chem Biodivers ; : e202301020, 2023 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-37815162

RESUMEN

Naturalness is gaining ground among perfumers and the use of natural raw materials is spreading in perfumery. Forgotten perfumery plants are of concern to develop innovative and natural ingredients for modern perfume industries. The main purpose of this study was to evaluate the potential interest of Crataegus monogyna Jacq. extracts as fragrance ingredient. To this end, various extractions, phytochemical characterizations and organoleptic evaluations of hawthorn were conducted on fresh, frozen, and dried flowering aerial parts, to identify those most likely to be of interest. More than a hundred compounds, anisaldehyde being the predominant one, were characterized for the first time in the volatile fraction, using HS-SPME-GC-MS technology. Impact of plant treatment and harvest year on the extracts were also discussed. From this work, a new and natural hawthorn-based ingredient was developed to complete the perfumers' palette.

4.
Molecules ; 28(2)2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36677948

RESUMEN

As an alternative to fossil volatile hydrocarbon solvents used nowadays in perfumery, investigation on essential oil of Commiphora wildii Merxm. oleo gum resin as a source of heptane is reported here. Heptane, representing up to 30 wt-% of this oleo gum resin, was successfully isolated from the C. wildii essential oil, using an innovative double distillation process. Isolated heptane was then used as a solvent in order to extract some noble plants of perfumery. It was found that extracts obtained with this solvent were more promising in terms of sensory analysis than those obtained from fossil-based heptane. In addition, in order to valorize the essential oil depleted from heptane, chemical composition of this oil was found to obtain, and potential biological activity properties were studied. A total of 172 different compounds were identified by GC-MS in the remaining oil. In vitro tests-including hyaluronidase, tyrosinase, antioxidant, elastase and lipoxygenase, as well as inhibitory tests against two yeasts and 21 bacterial strains commonly found on the skin-were carried out. Overall, bioassays results suggest this heptane-depleted essential oil is a promising active ingredient for cosmetic applications.


Asunto(s)
Aceites Volátiles , Aceites Volátiles/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Commiphora/química , Piel , Resinas de Plantas
5.
Chem Biodivers ; 19(2): e202100871, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34882976

RESUMEN

The volatile fraction of the leaves of Betula glandulosa Michx. has been investigated for its secondary metabolite composition by GC/MS and GC/FID. The rapid expansion of this shrub species in subarctic landscapes, like the ones found in Nunavik (Northern Québec, Canada), highly impacts ecosystem dynamics. Yet, despite its abundance, few phytochemical investigations have yet been conducted on this species. In this study, we present the first phytochemical investigation of the volatile metabolites of B. glandulosa leaves. Although no essential oil was isolated, volatile compounds were extracted from the hydrosol by steam distillation. The main metabolites observed were linalool (14.6-19.0 %), C6 oxylipins (known as green leaf volatiles, GLV; total of 18.2-40.2 %), eugenol (1.6-8.6 %) and α-terpineol (3.3-4.8 %). Dwarf birch is an important food source for insects and herbivores, so knowledge of its metabolite composition could help understand parts of its functional role in subarctic ecosystems. The composition of the volatile fraction could serve as marker for differentiating B. glandulosa from other dwarf birch species like Betula nana L.


Asunto(s)
Betula , Ecosistema , Herbivoria , Hojas de la Planta/química , Quebec
6.
Chem Biodivers ; 19(7): e202200158, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35604399

RESUMEN

Agricultural practices generate huge amounts of by-products, often simply discarded as waste that must be processed at some cost. The natural by-products revalorisation as raw material to produce high-added value ingredients for various industrial sectors may pave the way towards more sustainable industrial practices, via an optimised utilisation of natural resources. Integrating the circular economy precepts to production systems is considered to be a more and more promising management solution to significantly reduce the environmental impact of economic activities. This article discusses the valorisation of Rosa centifolia stem to produce a natural extract with cosmetic anti-aging potential. To do so, the cosmetic potential of 30 extracts obtained by maceration of agricultural by-products in a hydroalcoholic solvent was evaluated: their activities, as well as their inhibitory activities of specific enzymes were assessed in vitro to identify those that could be used effectively as anti-ageing actives while meeting the consumer's expectations in terms of sustainability, naturality, transparency and traceability.[1] A hydroalcoholic extract of R. centifolia stem revealed itself particularly promising due to its valuable anti-hyaluronidase and antioxidant activities, and its interesting anti-elastase and anti-inflammatory potential. The bio-guided fractionation of this extract allows the characterisation of three major compounds, e. g., isoquercitrin, quercitrin and euscaphic acid, never identified in R. centifolia previously.


Asunto(s)
Rosa , Antioxidantes/química , Antioxidantes/farmacología , Fitoquímicos/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Rosa/química
7.
Eur Arch Otorhinolaryngol ; 279(7): 3477-3484, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34716806

RESUMEN

BACKGROUND: Post-COVID-19 Olfactory impairment has a negative impact on quality of life. The Sniffin Sticks test 12 items (SST-12) can be used in quick olfactory disorders screening. Its evaluation in a post-covid-19 situation was the main objective of this work. METHODS: All patient impaired with a post-COVID olfactory loss were included while consulting to the ENT department. The clinical examination included an olfaction recovery self-assessment (VAS), a nasofibroscopy, a quality of life (QoL) assessment, the complete Sniffin' Sticks Test (SST), and the SST-12. RESULTS: Among the 54 patients included, 92% (n = 50) were correctly screened as olfactory impaired by SST-12. We report excellent correlations between SST-12 and SST (rho (52) = 0.98, p < 0.001), QoL(rho(52) = 0.33 p = 0.016), or VAS (rho(52) = 0.49, p < 0.001) assessments. CONCLUSIONS: SST-12 is a quick and reliable tool to screen large-scale population of post-COVID-19 olfactory impaired patients and could be used in a general daily clinical practice.


Asunto(s)
COVID-19 , Trastornos del Olfato , Anosmia , Humanos , Odorantes , Trastornos del Olfato/diagnóstico , Trastornos del Olfato/epidemiología , Trastornos del Olfato/etiología , Calidad de Vida , Olfato
8.
Cereb Cortex ; 30(4): 2199-2214, 2020 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-31812987

RESUMEN

Tuberous sclerosis complex (TSC) is a rare genetic disorder characterized by benign tumors throughout the body; it is generally diagnosed early in life and has a high prevalence of autism spectrum disorder (ASD), making it uniquely valuable in studying the early development of autism, before neuropsychiatric symptoms become apparent. One well-documented deficit in ASD is an impairment in face processing. In this work, we assessed whether anatomical connectivity patterns of the fusiform gyrus, a central structure in face processing, capture the risk of developing autism early in life. We longitudinally imaged TSC patients at 1, 2, and 3 years of age with diffusion compartment imaging. We evaluated whether the anatomical connectivity fingerprint of the fusiform gyrus was associated with the risk of developing autism measured by the Autism Observation Scale for Infants (AOSI). Our findings suggest that the fusiform gyrus connectivity captures the risk of developing autism as early as 1 year of age and provides evidence that abnormal fusiform gyrus connectivity increases with age. Moreover, the identified connections that best capture the risk of developing autism involved the fusiform gyrus and limbic and paralimbic regions that were consistent with the ASD phenotype, involving an increased number of left-lateralized structures with increasing age.


Asunto(s)
Trastorno Autístico/diagnóstico por imagen , Red Nerviosa/diagnóstico por imagen , Lóbulo Temporal/diagnóstico por imagen , Esclerosis Tuberosa/diagnóstico por imagen , Trastorno Autístico/etiología , Preescolar , Femenino , Humanos , Lactante , Imagen por Resonancia Magnética/métodos , Masculino , Estudios Prospectivos , Factores de Riesgo , Esclerosis Tuberosa/complicaciones
9.
Metabolomics ; 16(3): 31, 2020 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-32103392

RESUMEN

INTRODUCTION: Fine lavender and lavandin are perfume and medicinal plants originate from the South of France and are widely cultivated for their essential oils. Recently, cultivated plants suffered from a severe decline in France, due to the propagation of the yellow decline disease. This disease is caused by the stolbur phytoplasma, a bacterium transmitted by a sap-sucking insect, the planthopper. OBJECTIVES: In order to understand the complex relationships between host plant, pest, pathogen and environment responsible for the yellow decline of lavender, we use a metabolomic approach to highlight changes in chemical emissions from asymptomatic ("healthy") and symptomatic ("infected") plants. METHODS: Volatile compounds produced by fine lavender and lavandin were collected in the field using a dynamic headspace extraction approach. Afterwards, compounds trapped on Tenax adsorbent were thermodesorbed and analysed using an automated thermal desorption-gas chromatography-mass spectrometry (ATD-GC-MS). Multivariate statistical analyses was performed using principal component analysis and partial least square discriminant analyses. RESULTS: The untargeted screening of volatiles allowed the separation of asymptomatic and symptomatic plants according to their emissions. The approach was sufficiently accurate so as to separate the emissions according to the different stages of infection. Twelve compounds were found to be deregulated metabolites of yellow disease infection, common to fine lavender (variety 7713) and lavandin (variety abrial). CONCLUSION: The metabolomic approach allowed for the effective identification of chemical variations between infected and healthy plants in a complex field environment.


Asunto(s)
Lavandula/química , Metabolómica , Enfermedades de las Plantas , Compuestos Orgánicos Volátiles/metabolismo , Análisis Discriminante , Cromatografía de Gases y Espectrometría de Masas , Lavandula/crecimiento & desarrollo , Lavandula/metabolismo , Análisis de Componente Principal , Compuestos Orgánicos Volátiles/análisis
10.
Phytochem Anal ; 31(6): 778-785, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32337802

RESUMEN

INTRODUCTION: In situ analysis of volatile organic compounds (VOCs) emitted by plants is an important challenge in chemical ecology. The traditional approach usually consists in trapping compounds using dynamic headspace extraction (DHS) in-field, followed by gas chromatography analysis coupled with mass spectrometry (GC-MS and/or GC-FID) in the laboratory. OBJECTIVES: In this study, we evaluated the use of the new portable Torion T-9 GC-MS system for rapid and in situ analysis of VOCs emitted by fine lavender and lavandin species. MATERIAL AND METHODS: All field analyses were performed using a person-portable low-thermal mass GC system coupled with a miniature toroidal ion trap mass analyser (ppGC-ITMS): Torion T-9 portable GC-MS. Subsequently, multivariate statistical analyses were performed to determine chemical differences between species. RESULTS: Thirty compounds were separated and detected in all lavender above-ground samples in only 3 min of analysis. CONCLUSIONS: The portable GC-MS device enabled a rapid in-field distinction of Lavandula species based on their detected volatile profiles.


Asunto(s)
Lavandula , Compuestos Orgánicos Volátiles , Cromatografía de Gases y Espectrometría de Masas , Compuestos Orgánicos Volátiles/análisis
11.
Chem Biodivers ; 16(12): e1900506, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31633273

RESUMEN

Perfumes have always been products of great importance, mainly composed of natural, valuable and vegetal raw materials. Today, some of them have completely disappeared in perfumery, even though they are part of our cultural heritage and were commonly used in the past. Balm of Judea is one of the most noble, rare and fascinating ingredient long used in perfumery and medicine, that is missing today. After years of research, we collected a resin and an essential oil (steam distillation of fresh aerial parts) from Commiphora gileadensis (L.) C.Chr. native from Saudi Arabia and cultivated in Israel. The aims of this study were to i) identify the main reasons of the loss of the balm of Judea, ii) characterize the volatile composition of the resin and the essential oil and iii) evaluate their olfactory profile and assess their biological activity. Eighty-three compounds were identified in the resin, by a combination of GC-MS and GC/FID techniques, using direct injection and HS-SPME. α-Pinene (24.0 %), sabinene (43.8 %), ß-pinene (6.3 %) and cymene (3.6 %) were the main identified compounds, giving an intense, terpenic and lemony smell to the resin. Anti-inflammatory, wound-healing and whitening activities were highlighted. Sabinene (22.7 %), terpinen-4-ol (18.7 %), α-pinene (14.4 %) and cymene (13.6 %) were identified as the main components of the essential oil, giving a spicy, woody and lemony fragrance. Anti-inflammatory and whitening activities were emphasized.


Asunto(s)
Commiphora/química , Aceites Volátiles/química , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Commiphora/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Odorantes/análisis , Aceites Volátiles/aislamiento & purificación , Componentes Aéreos de las Plantas/química , Componentes Aéreos de las Plantas/metabolismo , Resinas de Plantas/química , Resinas de Plantas/metabolismo , Microextracción en Fase Sólida
12.
Chem Biodivers ; 16(10): e1900424, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31419369

RESUMEN

For centuries, perfumes consisted in a combination of natural ingredients, mainly of plant origin. From the 19th century on, the advent of organic synthesis enabled the deployment of multiple synthetic olfactory notes, enriching significantly the perfumers' portfolio. Chemistry is ever since the foundation of modern perfumery. However, sustainable-minded consumers, massively rejecting synthetics for safety and ecological issues, engaged a global return to nature in numerous sectors, and the fragrance industry is not outdone. Sustainable extraction of natural products, making use of innovative technologies, process intensification and agro-based solvents, constitutes the answer to develop eco-conceived fragrant ingredients covering every olfactory family without endangering biodiversity any further. The objective of this review is to draw a clear picture of where those technological advances are today and to assess the ones that may be effectively transposed at the industrial scale tomorrow.


Asunto(s)
Productos Biológicos/aislamiento & purificación , Odorantes/análisis , Perfumes/aislamiento & purificación , Productos Biológicos/química , Perfumes/química
13.
Chem Biodivers ; 16(8): e1900280, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31211502

RESUMEN

A headspace solid-phase microextraction (HS-SPME) method combined with gas chromatography-mass spectrometry (GC/MS) was developed and optimized for the extraction and the analysis of volatile organic compounds (VOCs) from lavandin and fine lavender roots. Optimal parameters to extract volatile molecules from ground and intact roots were determined using a divinylbenzene-carboxen-polydimethylsiloxane (DVB/CAR/PDMS) coating fiber at 70 °C for 60 min. A total of 99 VOCs, including 40 monoterpenoids, 15 sesquiterpenoids, 1 diterpenoid and 2 coumarins were detected. The main compounds detected in lavandin roots were fenchol, borneol, and coumarin. Performances of the optimized SPME GC/MS method were evaluated via the comparison of VOC emissions between roots from different cultivars of fine lavender (7713 and maillette) and lavandin (abrial and grosso). Chemometric analysis, using partial least squares-discriminant analysis (PLS-DA), suggests fifteen significant features as potential discriminatory compounds. Among them, ß-phellandrene allows discrimination between lavender and lavandin varieties.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas , Lavandula/química , Compuestos Orgánicos Volátiles/análisis , Análisis Discriminante , Lavandula/metabolismo , Análisis de los Mínimos Cuadrados , Extractos Vegetales/química , Raíces de Plantas/química , Raíces de Plantas/metabolismo , Microextracción en Fase Sólida , Compuestos Orgánicos Volátiles/aislamiento & purificación
14.
EMBO J ; 33(13): 1492-501, 2014 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-24859967

RESUMEN

Eukaryotic topoisomerases I (topo I) and II (topo II) relax the positive (+) and negative (-) DNA torsional stress (TS) generated ahead and behind the transcription machinery. It is unknown how this DNA relaxation activity is regulated and whether (+) and (-)TS are reduced at similar rates. Here, we used yeast circular minichromosomes to conduct the first comparative analysis of topo I and topo II activities in relaxing chromatin under (+) and (-)TS. We observed that, while topo I relaxed (+) and (-)TS with similar efficiency, topo II was more proficient and relaxed (+)TS more quickly than (-)TS. Accordingly, we found that the relaxation rate of (+)TS by endogenous topoisomerases largely surpassed that of (-)TS. We propose a model of how distinct conformations of chromatin under (+) and (-)TS may produce this unbalanced relaxation of DNA. We postulate that, while quick relaxation of (+)TS may facilitate the progression of RNA and DNA polymerases, slow relaxation of (-)TS may serve to favor DNA unwinding and other structural transitions at specific regions often required for genomic transactions.


Asunto(s)
ADN-Topoisomerasas de Tipo II/metabolismo , ADN de Hongos/metabolismo , ADN Superhelicoidal/metabolismo , Saccharomyces cerevisiae/enzimología , Cromatina , Cromosomas Fúngicos/genética , Cromosomas Fúngicos/metabolismo , ADN-Topoisomerasas de Tipo II/genética , ADN de Hongos/genética , ADN Superhelicoidal/genética , Regulación Fúngica de la Expresión Génica , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae
15.
Chem Biodivers ; 15(4): e1800031, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29505125

RESUMEN

Lichens are complex symbiotic organisms able to produce a vast array of compounds. The Algerian lichen diversity has only prompted little interest even given the 1085 species listed. Herein, the chemodiversity of four Algerian lichens including Cladonia rangiformis, Ramalina farinaceae, R. fastigiata, and Roccella phycopsis was investigated. A dereplication strategy, using ultra high performance liquid chromatography-high resolution-electrospray ionization-mass spectrometry (UHPLC-HRMS/MS), was carried out for a comprehensive characterization of their substances including phenolics, depsides, depsidones, depsones, dibenzofurans, and aliphatic acids. Some known compounds were identified for the first time in some species. Additionally, the lichenic extracts were evaluated for their antifungal and antimicrobial activities on human pathogenic strains (Candida albicans, C. glabrata, Aspergillus fumigatus, Staphylococcus aureus, and Escherichia coli). Cyclohexane extracts were found particularly active against human pathogenic fungi with MIC80 values ranging from 8 to 62.5 µg/mL, without cytotoxicity. This study highlights the therapeutic and prophylactic potential of lichenic extracts as antibacterial and antifungal agents.


Asunto(s)
Antibacterianos/farmacología , Antifúngicos/farmacología , Líquenes/química , Extractos Vegetales/farmacología , Argelia , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Aspergillus fumigatus/efectos de los fármacos , Candida/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Relación Dosis-Respuesta a Droga , Escherichia coli/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Staphylococcus aureus/efectos de los fármacos , Relación Estructura-Actividad , Espectrometría de Masas en Tándem
16.
J Sci Food Agric ; 98(2): 726-736, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28675447

RESUMEN

BACKGROUND: The current study presents new insight on the phytochemical content and biological activities of five Prunus domestica L. varieties ('Quetsche blanche de Létricourt', 'Mirabelle de Nancy', 'Perdrigon violet', 'Mirabelle de Provence', 'Reine-claude dorée'). RESULTS: The plum leaves were found to possess promising anti-aging activities by their capacity to inhibit 1,1-diphenyl-2-picrylhydrazyl (DPPH), elastase, hyaluronidase and lipoxygenase. After solid phase extraction (SPE), chlorogenic acid, rutin, quercetin and their derivatives were putatively identified by high-performance liquid chromatography coupled with tandem mass spectrometry using an electrospray ionization source (HPLC/ESI-MS/MS). CONCLUSION: The plum leaf, a by-product, provides an interesting valuable resource for use as a natural cosmetic product or as a food supplement. © 2017 Society of Chemical Industry.


Asunto(s)
Cosméticos/química , Extractos Vegetales/química , Hojas de la Planta/química , Prunus domestica/química , Cromatografía Líquida de Alta Presión , Flavonoides , Espectrometría de Masa por Ionización de Electrospray
17.
Neuroimage ; 148: 77-102, 2017 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-28087490

RESUMEN

In conjunction with the ISBI 2015 conference, we organized a longitudinal lesion segmentation challenge providing training and test data to registered participants. The training data consisted of five subjects with a mean of 4.4 time-points, and test data of fourteen subjects with a mean of 4.4 time-points. All 82 data sets had the white matter lesions associated with multiple sclerosis delineated by two human expert raters. Eleven teams submitted results using state-of-the-art lesion segmentation algorithms to the challenge, with ten teams presenting their results at the conference. We present a quantitative evaluation comparing the consistency of the two raters as well as exploring the performance of the eleven submitted results in addition to three other lesion segmentation algorithms. The challenge presented three unique opportunities: (1) the sharing of a rich data set; (2) collaboration and comparison of the various avenues of research being pursued in the community; and (3) a review and refinement of the evaluation metrics currently in use. We report on the performance of the challenge participants, as well as the construction and evaluation of a consensus delineation. The image data and manual delineations will continue to be available for download, through an evaluation website2 as a resource for future researchers in the area. This data resource provides a platform to compare existing methods in a fair and consistent manner to each other and multiple manual raters.


Asunto(s)
Esclerosis Múltiple/diagnóstico por imagen , Adulto , Algoritmos , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Sustancia Blanca/diagnóstico por imagen
18.
Chembiochem ; 18(7): 654-665, 2017 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-28140512

RESUMEN

The αv ß3 integrin receptor plays an important role in tumor metastasis and tumor-induced angiogenesis. The inhibition of this receptor with diverse ligands, antibodies, or cyclic peptides is a promising research field for the treatment of a variety of tumors. The replacement of Phe-(Me)Val dipeptide by a ß-lactam ring in Cilengitide has led to new products that show higher inhibitory activity than the parent cyclopeptide. In particular, substitution of a peptide bond ß-lactam-NH-Asp linkage by a ß-lactam-O-Asp ester linkage increases the activity of the new cyclodepsipeptide. In the same way it has been found that open-chain compounds of the form Asp-ß-lactam-Arg can interact with the receptor and inhibit its activity moderately. The integrin inhibitory activity of the synthesized compounds has been established by using the CGH array, a method that appears to be a more reliable trial than the classical adhesion test.


Asunto(s)
Depsipéptidos/farmacología , Integrina alfaVbeta3/antagonistas & inhibidores , Peptidomiméticos/farmacología , beta-Lactamas/farmacología , Depsipéptidos/síntesis química , Expresión Génica , Células Endoteliales de la Vena Umbilical Humana , Humanos , Conformación Molecular , Simulación del Acoplamiento Molecular , Peptidomiméticos/síntesis química , Venenos de Serpiente/química , Venenos de Serpiente/farmacología , beta-Lactamas/síntesis química
19.
BMC Complement Altern Med ; 17(1): 383, 2017 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-28768532

RESUMEN

BACKGROUND: Ficus umbellata is a medicinal plant previously shown to endow estrogenic properties. Its major component was isolated and characterized as 7-methoxycoumarin (MC). Noteworthy, coumarins and the respective active metabolite 7-hydroxycoumarin analogs have shown aromatase inhibitory activity, which is of particular interest in the treatment of estrogen-dependent cancers. The present work aimed at evaluating the estrogenic/antiestrogenic effects of MC in vitro and in vivo. METHODS: To do so, in vitro assays using E-screen and reporter gene were done. In vivo, a 3-day uterotrophic assay followed by a postmenopausal-like rat model to characterize MC as well as F. umbellata aqueous extract in ovariectomized Wistar rats was performed. The investigations focused on histological (vaginal and uterine epithelial height) and morphological (uterine wet weight, vagina stratification and cornification) endpoints, bone mass, biochemical parameters and lipid profile. RESULTS: MC induced a significant (p < 0.05) MCF-7 cell proliferation at a concentration of 0.1 µM, but did not inhibit the effect induced by estradiol in both E-screen and reporter gene assays. In vivo, MC treatment did not show an uterotrophic effect in both rat models used. However, MC (1 mg/kg) induced a significant increase (p < 0.01) of vaginal epithelial height. No significant change was observed with MC in abdominal fat weight, serum lipid levels and bone weight. CONCLUSION: These results suggest that MC has a weak estrogenic activity in vitro and in vivo that accounts only in part to the estrogenicity of the whole plant extract. MC could be beneficial with regard to vagina dryness as it showed a tissue specific effect without exposing the uterus to a potential tumorigenic growth.


Asunto(s)
Estrógenos/metabolismo , Ficus/química , Fitoestrógenos/farmacología , Extractos Vegetales/farmacología , Umbeliferonas/farmacología , Útero/efectos de los fármacos , Vagina/efectos de los fármacos , Tejido Adiposo/metabolismo , Animales , Inhibidores de la Aromatasa/farmacología , Huesos/efectos de los fármacos , Epitelio/efectos de los fármacos , Estradiol/metabolismo , Estradiol/farmacología , Antagonistas de Estrógenos/farmacología , Femenino , Células HEK293 , Humanos , Lípidos/sangre , Células MCF-7 , Ovariectomía , Posmenopausia , Ratas Wistar , Útero/metabolismo , Vagina/metabolismo
20.
BMC Complement Altern Med ; 17(1): 65, 2017 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-28109283

RESUMEN

BACKGROUND: Since the biological properties of propolis depend to the plants that can be found in a specific region, propolis from unexplored regions attracts the attention of scientists. Ethanolic extract of Cameroonian propolis (EEP) is used to treat various ailments including gynecological problems and amenorrhea. Since there were no scientific data to support the above claims, the present study was therefore undertaken to assess estrogenic properties of Cameroonian propolis. METHODS: To achieve our goal, the ability of EEP to induce MCF-7 cells proliferation in E-screen assay as well as to activate estrogen receptors α (ERα) and ß (ERß) in cell-based reporter gene assays using human embryonic kidney cells (HEK293T) transfected with ERs was tested. Further, a 3-day uterotrophic assay was performed and the ability of EEP to alleviate hot flushes in ovariectomized adult rats was evaluated. RESULTS: In vitro, EEP showed an antiestrogenic activity in both HEK293T ER-α and ER-ß cells. In vivo, EEP induced a significant increase in a bell shape dose response manner of the uterine wet weight, the total protein levels in the uterus, the uterine and vaginal epithelium height and acini border cells of mammary gland with the presence of abundant eosinophil secretions. Moreover, EEP induced a significant decrease in the total number, average duration as well as frequency of hot flushes after 3 days of treatment in rat (equivalent to a month in woman). The dose of 150 mg/kg exhibited the most potent estrogenic effects among all the tested doses. The UPLC-HRMS analysis showed the presence of caffeic acid derivatives and trirtepernoids in EEP, which are well known endowed with estrogenic properties. CONCLUSION: These results suggest that Ethanolic extract of Cameroonian propolis has estrogen-like effects in vivo and may alleviate some menopausal problems such as vaginal dryness and hot flushes. Ethanol-extracted Cameroobian propolis exhibited in vitro and in vivo estrogen-like effects. This extract may contain promising phytoestrogens.


Asunto(s)
Estrógenos/farmacología , Sofocos/tratamiento farmacológico , Própolis/química , Animales , Abejas , Camerún , Etanol , Femenino , Células HEK293 , Humanos , Glándulas Mamarias Animales/efectos de los fármacos , Tamaño de los Órganos/efectos de los fármacos , Ovariectomía , Própolis/farmacología , Ratas , Ratas Wistar , Útero/efectos de los fármacos , Vagina/efectos de los fármacos
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