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1.
Article de Anglais | MEDLINE | ID: mdl-38907641

RÉSUMÉ

BACKGROUND: The DNA mismatch repair (MMR) system serves as a sophisticated guardian of the precise functioning of the human genome. Dysregulation within this system is linked to the oncogenesis process. Reduced expression of MMR system proteins identified in salivary gland tumors (SGTs) suggests an increased risk of tumoral occurrence. This study aims to analyze the expression of MMR proteins in SGTs and discuss the relevance of this association to the development of these neoplasms. MATERIAL AND METHODS: This review was conducted following the PRISMA guidelines and was registered in PROSPERO (CRD42023465590). A comprehensive search of the PubMed/MEDLINE, Web of Science, Scopus, Embase, and ProQuest (non-peer reviewed platform) was performed to answer the question "Do DNA MMR system proteins exhibit expression in SGTs?". The methodological quality of the selected studies was assessed using the JBI's Critical Appraisal Tool. RESULTS: A total of 142 patients with benign SGTs and 84 with malignant SGTs were included in this review. The literature analysis showed a notable reduction in the expression of DNA MMR system proteins (hHMS2, hMLH1, hMSH3 and hMSH6) in the percentage of marked cells. CONCLUSIONS: The reduction in the expression of the DNA MMR system proteins suggests an interesting correlation with the development of malignant and benign SGTs. Nevertheless, further investigations are warranted to better clarify the precision of measuring biomarker protein expression.

2.
Phys Rev E ; 108(1-1): 014308, 2023 Jul.
Article de Anglais | MEDLINE | ID: mdl-37583232

RÉSUMÉ

We discuss the majority vote model coupled with scale-free networks and investigate its critical behavior. Previous studies point to a nonuniversal behavior of the majority vote model, where the critical exponents depend on the connectivity. At the same time, the effective dimension D_{eff} is unity for a degree distribution exponent 5/2<γ<7/2. We introduce a finite-size theory of the majority vote model for uncorrelated networks and present generalized scaling relations with good agreement with Monte Carlo simulation results. Our finite-size approach has two sources of size dependence: an external field representing the influence of the mass media on consensus formation and the scale-free network cutoff. The critical exponents are nonuniversal, dependent on the degree distribution exponent, precisely when 5/2<γ<7/2. For γ≥7/2, the model is in the same universality class as the majority vote model on Erdos-Rényi random graphs. However, for γ=7/2, the critical behavior includes additional logarithmic corrections.

3.
J Insect Sci ; 22(3)2022 May 01.
Article de Anglais | MEDLINE | ID: mdl-35596588

RÉSUMÉ

The expansion of Integrated Pest Management (IPM), including biological control, has had several positive consequences for the agricultural environment and participants in the production chain. To enable successful operation and applications of biological control, production of insects used for rearing natural enemies (parasitoids and predators) must be optimized to reduce time and costs and improve production both qualitatively and quantitatively. The present study evaluated the effect of wheat varieties, the main component of artificial diets for Ephestia kuehniella, on the reproductive performance and biological parameters of this flour moth, which is used for mass production of Trichogramma spp. (Hymenoptera: Trichogrammatidae) and other parasitoids and predators. Four varieties of wheat were compared: BRS 327, BRS Marcante, BRS Parrudo, and KBR, with and without the addition of corn E. kuehniella reared on 97% BRS 327 wheat flour + 3% nutritional yeast had the best biological parameters and substitution of corn for about half of the wheat increased the number of eggs per female.


Sujet(s)
Hymenoptera , Papillons de nuit , Animaux , Régime alimentaire , Femelle , Farine , Humains , Ovule , Triticum , Zea mays
4.
Phys Rev E ; 105(3-1): 034105, 2022 Mar.
Article de Anglais | MEDLINE | ID: mdl-35428121

RÉSUMÉ

We define a stochastic reaction-diffusion process that describes a consensus formation in a nonsedentary population. The process is a diffusive version of the majority-vote model, where the state update follows two stages: In the first stage, spins are allowed to jump to a random neighbor node with probabilities D_{+} and D_{-} for the respective spin orientations, and in the second stage, the spins in the same node can change its values according to the majority-vote update rule. The model presents a consensus formation phase when the concentration is greater than a threshold value and a paramagnetic phase on the converse for equal diffusion probabilities, i.e., maintaining the inversion symmetry. Setting unequal diffusion probabilities for the respective spin orientations is the same as applying an external magnetic field. The system undergoes a discontinuous phase transition for concentrations higher than the critical threshold on the external field. The individuals that diffuse more dominate the stationary collective opinion.

5.
Mol Ther ; 30(5): 1952-1965, 2022 05 04.
Article de Anglais | MEDLINE | ID: mdl-35339689

RÉSUMÉ

For coronavirus disease 2019 (COVID-19), effective and well-understood treatment options are still scarce. Since vaccine efficacy is challenged by novel variants, short-lasting immunity, and vaccine hesitancy, understanding and optimizing therapeutic options remains essential. We aimed at better understanding the effects of two standard-of-care drugs, dexamethasone and anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies, on infection and host responses. By using two COVID-19 hamster models, pulmonary immune responses were analyzed to characterize effects of single or combinatorial treatments. Pulmonary viral burden was reduced by anti-SARS-CoV-2 antibody treatment and unaltered or increased by dexamethasone alone. Dexamethasone exhibited strong anti-inflammatory effects and prevented fulminant disease in a severe disease model. Combination therapy showed additive benefits with both anti-viral and anti-inflammatory potency. Bulk and single-cell transcriptomic analyses confirmed dampened inflammatory cell recruitment into lungs upon dexamethasone treatment and identified a specifically responsive subpopulation of neutrophils, thereby indicating a potential mechanism of action. Our analyses confirm the anti-inflammatory properties of dexamethasone and suggest possible mechanisms, validate anti-viral effects of anti-SARS-CoV-2 antibody treatment, and reveal synergistic effects of a combination therapy, thus informing more effective COVID-19 therapies.


Sujet(s)
Traitements médicamenteux de la COVID-19 , Animaux , Anti-inflammatoires/pharmacologie , Anti-inflammatoires/usage thérapeutique , Anticorps antiviraux , Antiviraux , Cricetinae , Dexaméthasone/pharmacologie , SARS-CoV-2 , Transcriptome
6.
Phys Rev Lett ; 127(6): 062003, 2021 Aug 06.
Article de Anglais | MEDLINE | ID: mdl-34420329

RÉSUMÉ

We describe an analysis comparing the pp[over ¯] elastic cross section as measured by the D0 Collaboration at a center-of-mass energy of 1.96 TeV to that in pp collisions as measured by the TOTEM Collaboration at 2.76, 7, 8, and 13 TeV using a model-independent approach. The TOTEM cross sections, extrapolated to a center-of-mass energy of sqrt[s]=1.96 TeV, are compared with the D0 measurement in the region of the diffractive minimum and the second maximum of the pp cross section. The two data sets disagree at the 3.4σ level and thus provide evidence for the t-channel exchange of a colorless, C-odd gluonic compound, also known as the odderon. We combine these results with a TOTEM analysis of the same C-odd exchange based on the total cross section and the ratio of the real to imaginary parts of the forward elastic strong interaction scattering amplitude in pp scattering for which the significance is between 3.4σ and 4.6σ. The combined significance is larger than 5σ and is interpreted as the first observation of the exchange of a colorless, C-odd gluonic compound.

7.
NPJ Parkinsons Dis ; 7(1): 45, 2021 May 26.
Article de Anglais | MEDLINE | ID: mdl-34039994

RÉSUMÉ

Constipation is a common but not a universal feature in early PD, suggesting that gut involvement is heterogeneous and may be part of a distinct PD subtype with prognostic implications. We analysed data from the Parkinson's Incidence Cohorts Collaboration, composed of incident community-based cohorts of PD patients assessed longitudinally over 8 years. Constipation was assessed with the MDS-UPDRS constipation item or a comparable categorical scale. Primary PD outcomes of interest were dementia, postural instability and death. PD patients were stratified according to constipation severity at diagnosis: none (n = 313, 67.3%), minor (n = 97, 20.9%) and major (n = 55, 11.8%). Clinical progression to all three outcomes was more rapid in those with more severe constipation at baseline (Kaplan-Meier survival analysis). Cox regression analysis, adjusting for relevant confounders, confirmed a significant relationship between constipation severity and progression to dementia, but not postural instability or death. Early constipation may predict an accelerated progression of neurodegenerative pathology.

8.
Neotrop Entomol ; 50(1): 156-160, 2021 Feb.
Article de Anglais | MEDLINE | ID: mdl-32712943

RÉSUMÉ

Studies of insect feeding behavior are useful in different areas of entomology such as plant resistance, biology, and insecticide efficacy. For chewing insects, this kind of technique is well established, but for sap-sucking insects, especially tiny ones such as whiteflies, aphids, and psyllids, these tests can be laborious. Manipulation is difficult and can damage the plant, affecting the results. We describe here three types of cages for tests with small insects, one for seedlings in pots, a second for larger plants or plants in the field, and a third for caging insects on part of a leaf. These cages have been useful for different types of studies in addition to feeding behavior and can facilitate research with small phytophagous sucking insects.


Sujet(s)
Comportement alimentaire , Insectes , Animaux , Phloème , Plantes
9.
Eur J Neurol ; 28(1): 108-116, 2021 01.
Article de Anglais | MEDLINE | ID: mdl-32920893

RÉSUMÉ

BACKGROUND AND PURPOSE: Although highly disabling, the pathogenesis and evolution of fatigue in Parkinson's disease (PD) is largely unknown, and no sufficiently documented treatment currently exists. The aim of the present study was to investigate the evolution of fatigue during the first 9 years after diagnosis. METHODS: This study is part of the Norwegian ParkWest collaboration, a prospective population-based longitudinal cohort study. The present study comprised 191 newly diagnosed patients and 170 control participants. Fatigue was assessed by the Fatigue Severity Scale, with examinations at baseline and then every other year up to 9 years of follow-up. Linear mixed models were applied to investigate possible variables associated with fatigue. RESULTS: It was found that there was a statistically significant increase in the proportion of PD patients with fatigue during the first 9 years after diagnosis. A large proportion of patients had a significant increase or decrease in fatigue score between consecutive visits. In addition, the relative risk of persistent fatigue and ever having fatigue was higher than for controls. There were statistically significant longitudinal associations between higher levels of fatigue and female gender, comorbidity at baseline, depressive symptoms, dependency in activities of daily living and better cognitive functioning. Lower levels of fatigue were associated with the use of dopamine agonists. CONCLUSION: Fatigue is a common, severely limiting symptom in PD. This study demonstrates associations with other factors that could yield a better understanding of the symptom and thus possible treatment strategies, although further investigations are necessary to establish causal relationships.


Sujet(s)
Maladie de Parkinson , Activités de la vie quotidienne , Fatigue/épidémiologie , Fatigue/étiologie , Femelle , Études de suivi , Humains , Études longitudinales , Maladie de Parkinson/complications , Maladie de Parkinson/traitement médicamenteux , Maladie de Parkinson/épidémiologie , Études prospectives
10.
Int Endod J ; 53(10): 1348-1373, 2020 Oct.
Article de Anglais | MEDLINE | ID: mdl-32602945

RÉSUMÉ

OBJECTIVES: This systematic review aimed to compare the cytotoxicity of root canal filling materials (RCFMs) assessed using tetrazolium salt-based tests (TSBT), including the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, with those obtained using other cell viability assays. METHODS: A search was performed on PubMed, Scopus, Web of Science and OpenGrey up to March 2019, followed by a manual search. According to the Participants, Exposure, Comparator and Outcomes (PECO) criteria, in vitro studies that evaluated the cytotoxic effect of RCFMss on animal and/or human cells through TSBT and at least one other viability assay were compared. The methodological quality of selected papers was assessed using ToxRTool® and SciRAP® . Data were analysed using Wilcoxon's signed-rank test for paired samples and linear weighting kappa. RESULTS: A total of 230 non-duplicated records were identified. After applying the eligibility criteria, 55 studies were selected for methodological evaluation, seven were selected by manual searching, 22 were excluded for methodological reasons, and 40 were included. A total of 410 comparisons were performed between TSBT and distinct cell viability tests (DCVT). MTT had moderate concordance with DCVT using human cells (n = 138 samples) (P = 0.507; k = 0.4225) and animal cells (n = 122 samples) (P = 0.124; k = 0.5775). XTT had good concordance using human (n = 110 samples) (P = 0.507; k = 0.6336) and animal cells (n = 12 samples) (P = 0.564; k = 0.6604). MTT, XTT, WST and MTS assays showed moderate concordance with DCVT (n = 410 samples) (P = 0.375; k = 0.5138) and complete agreement in 226 samples. DISCUSSION: The included studies had methodological heterogeneity that was minimized by the systematic review methodology. CONCLUSIONS: MTT and XTT do not cause over- or underestimation of cell viability during cytotoxicity screening of root canal filling materials, implying that these assays can be considered reliable for this purpose. Nonetheless, the development of protocols for the cytotoxic screening of these materials on 3D tissue-like cultures aiming to improve their predictability in the clinical scenario is suggested.


Sujet(s)
Cavité pulpaire de la dent , Produits d'obturation des canaux radiculaires , Animaux , Survie cellulaire , Humains , Produits d'obturation des canaux radiculaires/toxicité , Obturation de canal radiculaire , Sels de tétrazolium
11.
Br J Oral Maxillofac Surg ; 58(1): 109-111, 2020 01.
Article de Anglais | MEDLINE | ID: mdl-31761568

RÉSUMÉ

Intramuscular myxomas are myxoid neoplasms that mainly affect the muscles of the thigh, upper arm, and gluteus. In the head and neck region they are rare, and we know of only two reported cases in the masseter muscle. We think that this is the third. A 60-year-old woman presented with a painless nodule on the right side of her face. Magnetic resonance imaging showed a well-defined mass restricted to the muscle, with no infiltration into adjacent structures. Microscopic analysis confirmed the gross examination, and showed a tumour with copious myxoid stroma, scattered spindle to stellate cells, and an absence of atypia, which did not stain for CD34, S100, or smooth-muscle actin. A final diagnosis of intramuscular myxoma was made. Despite its rarity, it is important to consider this neoplasm in the differential diagnosis of tumours with a gelatinous-like appearance that involve masticatory muscles of the head and neck.


Sujet(s)
Tumeurs musculaires/diagnostic , Myxome/diagnostic , Diagnostic différentiel , Femelle , Humains , Imagerie par résonance magnétique , Muscle masséter , Adulte d'âge moyen , Syndrome
12.
J Stomatol Oral Maxillofac Surg ; 121(1): 84-89, 2020 Feb.
Article de Anglais | MEDLINE | ID: mdl-30794883

RÉSUMÉ

Medication related osteonecrosis of the jaw (MRONJ) is characterized by exposed necrotic bone in the maxillofacial region that persists for more than eight weeks in patients taking antiresorptive or antiangiogenic drugs for bone metastasis or osteoporosis. The management of such condition depends on several factors, among which the staging of MRONJ. Though, a specific gold standard treatment has not been established to date. The aim of this case series is to describe the outcome of surgical treatment of MRONJ with the adjunct of Platelet-rich Fibrin (PRF). Eleven patients under therapy with alendronate underwent surgical removal of necrotic bone and debridement, followed by placement of PRF membranes in the bone defect. The outcome of the surgical treatment was successful in all patients, in a follow-up range from 12 to 36 months. In the cases presented, the macroscopic evaluation showed excellent and fast soft tissue healing, with no recurrence of bone exposure and no signs of infections. PRF membranes were also effective for postsurgical pain control. The use of PRF may represent a valuable adjunct in the surgical management of MRONJ.


Sujet(s)
Ostéonécrose de la mâchoire associée aux biphosphonates , Fibrine riche en plaquettes , Humains , Cicatrisation de plaie
13.
Eur J Neurol ; 27(1): 43-50, 2020 01.
Article de Anglais | MEDLINE | ID: mdl-31293044

RÉSUMÉ

BACKGROUND AND PURPOSE: Parkinson's disease (PD), dementia with Lewy bodies (DLB) and Alzheimer's disease (AD) are three of the most common neurodegenerative disorders. Up to 20% of these patients have the wrong diagnosis, due to overlapping symptoms and shared pathologies. A cerebrospinal fluid (CSF) biomarker panel for AD is making its way into the clinic, but an equivalent panel for PD and DLB and for improved differential diagnoses is still lacking. Using well-defined, community-based cohorts and validated analytical methods, the diagnostic value of CSF total-α-synuclein (t-α-syn) alone and in combination with total tau (t-tau) in newly diagnosed patients with PD, DLB and AD was determined. METHODS: Cerebrospinal fluid concentrations of t-α-syn were assessed using our validated in-house enzyme-linked immunosorbent assay in 78 PD patients, 20 AD patients, 19 DLB patients and 32 controls. t-tau was measured using a commercial assay. Diagnostic performance was assessed by receiver operating characteristic curve analysis. RESULTS: Compared to controls (mean 517 pg/ml), significantly lower levels of CSF t-α-syn in patients with PD (434 pg/ml, 16% reduction, P = 0.036), DLB (398 pg/ml, 23% reduction, P = 0.009) and AD (383 pg/ml, 26% reduction, P = 0.014) were found. t-α-syn levels did not differ significantly between PD, DLB and AD. The t-tau/t-α-syn ratio showed an improved performance compared to the single markers. CONCLUSION: This is the first study to compare patients with PD, DLB and AD at the time of diagnosis. It was found that t-α-syn can contribute as a teammate with tau in a CSF biomarker panel for PD and DLB, and strengthen the existing biomarker panel for AD.


Sujet(s)
Maladie d'Alzheimer/diagnostic , Maladie à corps de Lewy/diagnostic , Maladie de Parkinson/diagnostic , alpha-Synucléine/liquide cérébrospinal , Protéines tau/liquide cérébrospinal , Sujet âgé , Sujet âgé de 80 ans ou plus , Maladie d'Alzheimer/liquide cérébrospinal , Marqueurs biologiques/liquide cérébrospinal , Diagnostic différentiel , Femelle , Humains , Maladie à corps de Lewy/liquide cérébrospinal , Mâle , Adulte d'âge moyen , Maladie de Parkinson/liquide cérébrospinal
14.
Neotrop Entomol ; 49(2): 250-257, 2020 Apr.
Article de Anglais | MEDLINE | ID: mdl-31797306

RÉSUMÉ

Huanglongbing (HLB), the most destructive citrus disease worldwide, was first recorded in Brazil in 2004, and since then, more than 50 million trees identified with this disease have been eliminated. The disease is managed mainly by controlling the psyllid vector Diaphorina citri Kuwayama, 1908 (Hemiptera: Liviidae). Although the presence of the insect in commercial citrus groves is low, HLB infection rates increase in areas bordering the groves. The disease is transmitted by psyllids from host citrus plants in areas outside the managed groves, such as abandoned or organic groves and residential trees, and from orange jasmine plants in urban settings. In order to provide information to support HLB control, this study evaluated the biotic and abiotic variables that affect the dynamics of D. citri populations after releases of the parasitoid wasp Tamarixia radiata (Waterston, 1922) (Hymenoptera: Eulophidae) in external sources of HLB inocula. The study was divided into two parts. After releasing the parasitoids in non-commercial areas, we determined the following: (a) the variables that significantly affected the number of nymphs collected on shoots in the same non-commercial area; (b) the variables that significantly affected the number of adult psyllids collected in a neighboring commercial citrus area. Our results indicated that the number of nymphs in external areas was affected only by the host plant and rainfall. However, periodic parasitoid releases significantly reduced the number of adult psyllids collected in the commercial area. The results indicate that the release of parasitoids in external sources of inocula has the potential to maximize actions for D. citri control, contributing to the reduction of psyllid populations in commercial areas. Consequently, this strategy may help to manage the disease infection without an increase in insecticide use.


Sujet(s)
Hemiptera/parasitologie , Lutte biologique contre les nuisibles , Guêpes/physiologie , Animaux , Brésil , Citrus , Hemiptera/microbiologie , Maladies des plantes/microbiologie
15.
Arq. bras. med. vet. zootec. (Online) ; 71(6): 1773-1780, Nov.-Dec. 2019. tab
Article de Portugais | LILACS, VETINDEX | ID: biblio-1055107

RÉSUMÉ

A laminite endocrinopática tem acometido um número crescente de equinos com sinais de obesidade. Em um estudo recente com fêmeas jovens (até cinco anos) da raça Campolina, demonstraram-se indícios de alterações no dígito, ainda discretas, aparentemente associadas ao aumento da adiposidade. Com a hipótese de que essa associação é mais evidente em animais em faixa etária superior, o objetivo do presente estudo foi estudar éguas adultas (acima de cinco anos) da raça Campolina com e sem obesidade, avaliando-se radiograficamente a relação espacial entre estojo córneo e falange distal. Foram utilizadas 27 éguas entre seis e 14 anos de idade, sendo analisadas variáveis de adiposidade e medidas radiográficas dos cascos dos membros torácicos de equinos com escore corporal de 5 a 7/9 (grupo controle) e de 8 a 9 (grupo obeso). Foram feitas comparações entre os grupos e correlacionaram-se as variáveis de adiposidade com variáveis casco. A distância de afundamento da falange distal foi cerca de 20% superior nas éguas obesas (12,3±2,5 contra 10,2±2,2mm no grupo controle). Esse parâmetro também correlacionou (P<0,01) com vários parâmetros de adiposidade, com destaque para o escore de condição corporal (r=0,47) e a circunferência de pescoço a 75% (r=0,42). Os resultados corroboram estudos prévios que demonstraram associação entre obesidade e indícios de separação entre falange distal e estojo córneo em equinos de raças nacionais, comprovando, assim, a utilidade da avaliação radiográfica nesses animais. Em conclusão, éguas da raça Campolina com obesidade possuem alterações evidentes na relação espacial entre estojo córneo e falange distal, que se intensificam com o aumento da idade e da adiposidade.(AU)


In a recent study with young females (up to 5 years old) of the Campolina breed, there were discrete indications of alterations in the digit, apparently associated to the increase in adiposity. With the hypothesis that this association is more evident in horses in the upper age group, the objective was to study Campolina adult mares (above 5 years) with and without obesity, evaluating radiographically the spatial relationship between the horn and distal phalanx. Eighteen mares between six and fourteen years and with a body score of 5 to 7/9 (Control Group) and 8 to 9 (Obeso Group) were used. Adiposity and radiographic measurements from the forelimbs were analyzed. Comparisons were made between groups and adiposity variables were correlated with hoof variables. The sinking distance of the distal phalanx was about 20% higher in obese mares (12.3±2.5 versus 10.2±2.2mm). This parameter also correlated (P< 0.01) with several adiposity parameters, with emphasis on body score condition (r= 0.47) and neck circumference at 75% (r= 0.42). In conclusion, Campolina mares with obesity have obvious alterations in the spatial relation between the corneal and the distal phalanx, which get intense according to increases in age and adiposity.(AU)


Sujet(s)
Animaux , Femelle , Poids et mesures du corps/médecine vétérinaire , Phalanges des orteils/anatomie et histologie , Sabot et griffe/anatomie et histologie , Equus caballus/anatomie et histologie
16.
Int J Cosmet Sci ; 41(3): 265-273, 2019 Jun.
Article de Anglais | MEDLINE | ID: mdl-30982995

RÉSUMÉ

OBJECTIVES: In view of the lack of studies about the morphological and structural changes caused by solar radiation in young people, the aim of the present study was to evaluate the photoageing-related changes in the skin of different age groups by biophysical and imaging techniques. METHODS: Forty-four healthy female subjects were divided into two age groups: Group 1 (G1): 18-35 years old and Group 2 (G2): 40-60 years old. The skin of malar region of the face was evaluated in terms of mechanical properties, disorder in the pigmentation pattern, morphological and structural changes using the Cutometer® , Colorimeter® , Visioface® and Dermascan C® devices and reflectance confocal microscopy (Vivascope® ). RESULTS: The results showed that the main changes in the skin of G1 were related to the pigmentation pattern, the papilla format and depletion of thin collagen fibres. These alterations were also observed in the skin of G2, but with more pronounced effects. CONCLUSION: The knowledge about the skin changes caused by photoageing obtained in this study is very important for the development of dermocosmetic products for more effective treatments particularly focused on this type of skin. Finally, objective characterization of photoageing showed the importance of photoprotective habits since the first years of life in order to retard the appearance of skin changes caused by solar radiation.


OBJECTIFS: Compte tenu du manque d'études sur les modifications structurelles et morphologiques causées par le rayonnement solaire chez les jeunes gens, le but de la présente étude était d'évaluer les changements liés au photovieillissement de la peau de différents groupes d'âges grâce des techniques de biophysique et d'imagerie. MÉTHODES: Quarante-quatre sujets féminins en bonne santé ont été divisés en deux groupes d'âges : Groupe 1 (G1) : 18-35 ans et Groupe 2 (G2) : 40-60 ans. La peau des régions malaires du visage a été évaluée en termes de propriétés mécaniques, troubles du schéma de pigmentation, et changements morphologiques et structurels à l'aide des dispositifs Cutometer®, Colorimeter®, Visioface® et Dermascan C® et de la microscopie confocale par réflectance (Vivascope®). RÉSULTATS: Les résultats ont montré que les principaux changements au niveau de la peau du G1 étaient liés au schéma de pigmentation, au format papillaire et à la déplétion de fines fibres de collagène. Ces altérations ont également été observées au niveau de la peau du G2, mais avec des effets plus prononcés. CONCLUSION: Les connaissances sur les modifications cutanées causées par le photovieillissement acquises grâce à cette étude sont très importantes pour le développement de produits dermo-cosmétiques pour des traitements plus efficaces axés plus particulièrement sur ce type de peau. Et enfin, la caractérisation objective du photovieillissement a montré l'importance des habitudes photoprotectrices depuis les premières années de vie afin de retarder l'apparition de modifications cutanées causées par le rayonnement solaire.


Sujet(s)
Vieillissement de la peau/effets des radiations , Lumière du soleil/effets indésirables , Rayons ultraviolets/effets indésirables , Adolescent , Adulte , Phénomènes biophysiques , Brésil , Élasticité , Femelle , Humains , Adulte d'âge moyen , Phénomènes physiologiques de la peau , Pigmentation de la peau , Viscosité , Jeune adulte
17.
Biomed Pharmacother ; 113: 108728, 2019 May.
Article de Anglais | MEDLINE | ID: mdl-30856536

RÉSUMÉ

Glioblastoma, which is highly invasive and has a poor patient prognosis, is the most common type of brain tumor. Flavonoids have known antiproliferative and antineoplastic effects, such as apoptosis induction and tumor growth inhibition. We investigated the effects of treatment with three flavonoids (BAS-1, BAS-4, and BAS-6) isolated from the Amazon plant Brosimum acutifolium on the proliferation and migration of the C6 glioma cell line. Cytotoxicity was evaluated by MTT assay, and morphological changes were evaluated by phase-contrast microscopy and by transmission electron microscopy. Apoptosis was determined using Annexin V-FITC-propidium iodide (PI) staining. A hemolysis assay was used to evaluate plasma membrane injury. Antiproliferative effects were assessed by wound migration and colony formation assays. Mitochondrial transmembrane potential (ΔΨm) was determined using JC-1 dye and flow cytometry. To identify the flavonoid targets, western blotting was performed. BAS-1 and BAS-4 reduced C6 cell proliferation in a dose-dependent manner. BAS-6 showed no effect. Due to its high toxicity toward primary glial cells and its high hemolytic index, BAS-1 was not used in the remaining experiments. BAS-4 treatment did not induce cytotoxicity in primary glial cells; however, in glioma cells, it suppressed migration and invasion and led to apoptosis through mitochondrial damage, ΔΨm loss, cell cycle arrest, and reduced AKT phosphorylation, which is a component of the main cell survival pathway. We conclude that BAS-4 showed potential activity against glioma by inducing apoptosis mediated by ΔΨm loss and AKT pathway disruption, and future studies should further evaluate BAS-4 as a promising antineoplastic agent against glioblastoma.


Sujet(s)
Tumeurs du cerveau/traitement médicamenteux , Flavonoïdes/pharmacologie , Gliome/traitement médicamenteux , Moraceae/composition chimique , Animaux , Antinéoplasiques d'origine végétale/administration et posologie , Antinéoplasiques d'origine végétale/isolement et purification , Antinéoplasiques d'origine végétale/pharmacologie , Apoptose/effets des médicaments et des substances chimiques , Tumeurs du cerveau/anatomopathologie , Points de contrôle du cycle cellulaire/effets des médicaments et des substances chimiques , Lignée cellulaire tumorale , Prolifération cellulaire/effets des médicaments et des substances chimiques , Survie cellulaire/effets des médicaments et des substances chimiques , Relation dose-effet des médicaments , Flavonoïdes/administration et posologie , Flavonoïdes/isolement et purification , Cytométrie en flux , Glioblastome/traitement médicamenteux , Glioblastome/anatomopathologie , Gliome/anatomopathologie , Potentiel de membrane mitochondriale/effets des médicaments et des substances chimiques , Phosphorylation/effets des médicaments et des substances chimiques , Protéines proto-oncogènes c-akt/métabolisme , Rats , Rat Wistar
18.
Appl Opt ; 57(27): 7910-7914, 2018 Sep 20.
Article de Anglais | MEDLINE | ID: mdl-30462059

RÉSUMÉ

Thermal conductivity of Er3+-doped yttrium aluminum perovskite has been obtained by the use of laser induced temperature distribution and time-independent heat propagation equations. By using the spatially resolved microluminescence technique, the fluorescence spectra on the sample surface were mapped during the laser focused heating process, and the local temperature was measured at different spots on the sample surface with micrometric resolution. Significant information about the temperature profile was obtained following the maximum temperature of the laser spot and the behavior of the heat diffusion on the surface of the irradiation side. These data were finally used to feed the heat propagation equations from where the thermal conductivity was evaluated.

19.
Acta Neurol Scand ; 138(5): 394-399, 2018 Nov.
Article de Anglais | MEDLINE | ID: mdl-29947088

RÉSUMÉ

OBJECTIVES: Parkinson's disease (PD)-related fatigue is a significant clinical problem, and the pathological processes that cause fatigue remain unknown. The aim of the present study was to explore the possible association of peripheral inflammation markers and fatigue in PD. MATERIALS & METHODS: We included 47 drug naïve, newly diagnosed PD patients with low (≤3.0) or high (>5.5) fatigue levels as evaluated by the Fatigue Severity Scale (FSS). Strict diagnostic criteria were applied for inclusion. Patients with possible confounding causes for fatigue were excluded. Serum concentrations of a panel of inflammatory markers (IL-8, TNF-α, MCP1, MIP-1ß, IL-6, IL-6R, p-selectin, E-selectin-1, ICAM, VCAM-1, CCL5, IL1-Ra, and TNFR1) were measured using ELISA technology in PD patients with and without fatigue to assess the potential relationships of fatigue in newly diagnosed, treatment-naïve patients. RESULTS: Fatigued PD patients had significantly higher levels of the IL-1 receptor antagonist (IL1-Ra) (1790 pg/mL (SD1007) vs 1262 pg/mL (SD379)) and of the adhesion molecule VCAM 1 (1071 ng/mL (SD276) vs 895 ng/mL (SD229)) than non-fatigued patients. A binary logistic regression model, including high or low FSS score as the dependent variable and UPDRS motor score, MADRS, MMSE, ESS, and IL1-Ra/VCAM-1 as independent variables, showed a significant effect both for IL1-Ra and VCAM-1. CONCLUSIONS: Higher serum levels of the inflammatory molecules IL1-Ra and VCAM-1 were associated with higher fatigue levels in patients with newly diagnosed, drug-naïve PD. These findings highlight an altered immune response as a potential contributor to PD-related fatigue, from the earliest clinical stages of the disease.


Sujet(s)
Fatigue/étiologie , Inflammation/complications , Antagoniste du récepteur à l'interleukine-1/sang , Maladie de Parkinson/complications , Molécule-1 d'adhérence des cellules vasculaires/sang , Adulte , Sujet âgé , Marqueurs biologiques/sang , Fatigue/sang , Femelle , Humains , Inflammation/sang , Mâle , Adulte d'âge moyen , Maladie de Parkinson/sang
20.
Phys Rev E ; 97(2-2): 029901, 2018 Feb.
Article de Anglais | MEDLINE | ID: mdl-29548199

RÉSUMÉ

This corrects the article DOI: 10.1103/PhysRevE.93.042111.

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