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1.
Acta Endocrinol (Buchar) ; 17(4): 449-454, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35747862

RESUMEN

Context: Human zonulin is a protein that regulates the intercellular tight junctions in various tissues and organs of the human body. Hashimoto's thyroiditis (HT) is one of the most common endocrine autoimmune disorder, but the role of increased intestinal permeability in its pathogenesis is still being studied. Objective and design: This pilot cross-sectional study investigates serum zonulin concentration in adults with Hashimoto's thyroiditis and assesses the relationship between zonulin levels, clinical hormonal and immunological characteristics. Subjects and methods: A group of 62 adults with HT participated in this study and were divided into three groups: hypothyroid (n=33) euthyroid (n=25) and hyperthyroid (n=4). Serum zonulin was determined using an ELISA method. Results: Age, gender and BMI were different between groups (hypothyroid and euthyroid ones). Serum zonulin values ranged from 2.6 to 198.0 ng/mL in participants. A direct positive correlation was found between serum zonulin levels and weight and BMI (r = 0.351, p = 0.008 and r = 0.236, p = 0.05, respectively). Conclusions: There is no correlation between zonulin and thyroid hormones or autoantibodies in Hashimoto thyroiditis patients. There is a difference in zonulin levels between the studied groups, but they are not statistically significant.

3.
J Eur Acad Dermatol Venereol ; 28(9): 1214-8, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24028636

RESUMEN

BACKGROUND: Correct evaluation of horizontal scalp biopsies requires accurate gross sectioning and embedding of the tissue. The most common issue during processing includes incorrect specimen bisection. OBJECTIVES: To verify if (i) ex vivo assessment of scalp biopsies by contact dermatoscopy can identify the correct plane of transverse bisection as well as (ii) if using contact dermatoscopy on the glass slides can be useful to control the tissue processing and expedite sign-out. MATERIALS AND METHODS: For the first aim, dermatoscopic pictures of 43 scalp biopsies were printed and shown to 10 dermatology residents not involved in the study, who were asked to identify and highlight the dermo-epidermal junction. For the second aim, dermatoscopic captions of 40 horizontal sections were evaluated in a blinded way for the size of the specimen as well as the level and plane of bisection. The agreement was investigated using Cohen's κ statistics. RESULTS: Ten independent observers were able to correctly identify the dermo-epidermal junction as a brownish wavy line in 95.3% cases. The Cohen's κ statistics showed almost perfect agreement. Two independent pathologists agreed on the specimen size in all cases, on the specimen plane in 39 cases and on the specimen level on 35 cases. The Cohen's κ statistics showed almost complete agreement for the size and plane of bisection and substantial agreement for the level of section. CONCLUSION: Ex vivo dermatoscopy of scalp biopsies may be a new way to decrease laboratory costs and improve turnaround time in hair pathology as this technique optimally guides the correct bisection at 1-1.5 mm below the junction. Ex vivo dermatoscopy on the slides may expedite sign out after the initial bisection.


Asunto(s)
Dermoscopía , Cuero Cabelludo/patología , Manejo de Especímenes/normas , Biopsia/normas , Humanos
4.
J Eur Acad Dermatol Venereol ; 28(11): 1560-2, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24112758

RESUMEN

BACKGROUND: Onychomatricoma is a benign fibroepithelial nail matrix tumor that infiltrates the nail plate leading to multiple tunneled cavities lined with matrix epithelium and filled with serum. Diagnostic features of onychomatricoma on reflectance confocal microscopy (RCM) have not been previously described. OBJECTIVE: We sought to demonstrate the feasibility of using RCM to diagnose onychomatricoma. METHODS: Reflectance confocal microscopy was used to evaluate four patients with onychomatricoma before tumor excision. We evaluated the affected nail and one unaffected nail of each patient with VivaScope 1500 (Lucid Inc., Rochester, NY, USA). RESULTS: Reflectance confocal microscopy evaluation of onychomatricomas revealed longitudinal dark areas and bright/grey lines, forming channel like structures. The channels were outlined by bright circular lines with grey dot centers. These RCM features correlated with the pathology of the onychomatricomas within the nail plate. LIMITATIONS: Proximal portion of onychomatricoma was not reach by RCM. CONCLUSIONS: Reflectance confocal microscopy can assist in rapid and noninvasive diagnosis of onychomatricoma showing characteristic channel like structures within nail plates.


Asunto(s)
Microscopía Confocal/métodos , Enfermedades de la Uña/patología , Neoplasias Fibroepiteliales/patología , Estudios de Factibilidad , Humanos , Enfermedades de la Uña/diagnóstico , Enfermedades de la Uña/cirugía , Uñas/patología , Neoplasias Fibroepiteliales/diagnóstico , Neoplasias Fibroepiteliales/cirugía , Reproducibilidad de los Resultados
5.
mBio ; : e0152224, 2024 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-39189744

RESUMEN

Extracellular vesicles (EV), key players in cell-to-cell communication, may contribute to disease propagation in several neurodegenerative diseases, including Alzheimer's disease (AD), by favoring the dissemination of neurotoxic proteins within the brain. Interestingly, growing evidence supports the role of herpes simplex virus type 1 (HSV-1) infection in the pathogenesis of AD. Here, we investigated whether HSV-1 infection could promote the spread of phosphorylated tau (ptau) among neurons via EV. We analyzed the ptau species that were secreted via EV following HSV-1 infection in neuroblastoma cells and primary neurons, focusing particularly on T205, T181, and T217, the phosphorylation sites mainly associated with AD. Moreover, by overexpressing human tau tagged with GFP (htauGFP), we found that recipient tau knockout (KO) neurons uptook EV that are loaded with HSV-1-induced phtauGFP. Finally, we exploited an in vivo model of acute infection and assessed that cerebral HSV-1 infection promotes the release of ptau via EV in the brain of infected mice. Overall, our data suggest that, following HSV-1 infection, EV play a role in tau spreading within the brain, thus contributing to neurodegeneration.IMPORTANCEHerpes simplex virus type 1 (HSV-1) infection that reaches the brain has been repeatedly linked with the appearance of the pathognomonic markers of Alzheimer's disease (AD), including accumulation of amyloid beta and hyperphosphorylated tau proteins, and cognitive deficits. AD is a multifactorial neurodegenerative disease representing the most common form of dementia in the elderly, and no cure is currently available, thus prompting additional investigation on potential risk factors and pathological mechanisms. Here, we demonstrate that the virus exploits the extracellular vesicles (EV) to disseminate phosphorylated tau (ptau) among brain cells. Importantly, we provide evidence that the HSV-1-induced EV-bearing ptau can be undertaken by recipient neurons, thus likely contributing to misfolding and aggregation of native tau, as reported for other AD models. Hence, our data highlight a novel mechanism exploited by HSV-1 to propagate tau-related damage in the brain.

7.
J Eur Acad Dermatol Venereol ; 27(10): 1299-303, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22449222

RESUMEN

BACKGROUND: Scalp biopsies are crucial for the diagnosis of cicatricial alopecia. However, the pathologic interpretation may not be diagnostic if biopsy is not obtained from the correct site. This is particularly relevant for cicatricial alopecia as the disease may be focal and disease activity difficult to appreciate by the naked eye. OBJECTIVE: To report a new simple technique to select the optimal biopsy site in cicatricial alopecia. METHODS: In the last 2 years we performed dermoscopy guided scalp biopsies using handled dermatoscopes in 80 patients with different forms of cicatricial alopecia. Biopsy site was selected based on presence of the following dermatoscopic features: perifollicular concentric white scales in lichen planopilaris, frontal fibrosing alopecia (FFA) and discoid lupus erythematosus (DLE); hair tufts in folliculitis decalvans, hairs surrounded by a peripilar grey-white halo in central centrifugal cicatricial alopecia and follicular red dots or keratotic plugs in DLE. RESULTS: The dermoscopy guided biopsies yielded a definitive pathological diagnosis in 95% of the cases. COMMENT: The advantage of this method is that it is a fast, precise way to identify even individually affected follicles in early or focal cicatricial alopecia. It also allows for the morphologic characterization of particular follicular structures.


Asunto(s)
Alopecia/diagnóstico , Alopecia/patología , Dermoscopía/métodos , Cuero Cabelludo/patología , Biopsia , Foliculitis/patología , Folículo Piloso/patología , Humanos , Lupus Eritematoso Discoide/patología
8.
Br J Dermatol ; 166(6): 1289-94, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22348354

RESUMEN

BACKGROUND: A patient's ethnicity can be an important clue in the diagnosis of scarring alopecia as some disorders such as traction alopecia (TA) and central centrifugal cicatricial alopecia (CCCA) are more prevalent in or exclusive to African-Americans. OBJECTIVES: To perform a retrospective review of 60 scalp biopsies from African-American patients including 25 cases of CCCA, 22 cases of TA, five cases of frontal fibrosing alopecia, three cases of discoid lupus erythematosus, three cases of hair breakage and two cases of alopecia areata. METHODS: Serial horizontal and vertical sections were examined. RESULTS: Features characteristic of the African-American scalp include: golf club-shaped bulb, elliptical shape of the hair shaft, asymmetrical outer root sheath and paired grouping of hair follicles. Clues to the diagnosis of CCCA include: premature desquamation of the inner root sheath, goggles and naked hair shafts in fibrous streamers. Diagnosis of TA is suggested by preserved sebaceous glands along with follicular miniaturization and drop-out. CONCLUSIONS: The clues reported here aim to help the dermatopathologists to: recognize at a glance that they are dealing with a scalp biopsy from an African-American patient; make the most probable diagnosis by connecting the clues (even if only vertical sections are present); and understand the morphological basis for the susceptibility of the African hair to damage.


Asunto(s)
Alopecia/patología , Negro o Afroamericano , Cabello/patología , Lupus Eritematoso Discoide/patología , Cuero Cabelludo/patología , Alopecia/etnología , Biopsia/métodos , Folículo Piloso/patología , Humanos , Lupus Eritematoso Discoide/etnología , Estudios Retrospectivos
9.
Comput Struct Biotechnol J ; 20: 4195-4205, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36016719

RESUMEN

ABCG2/BCRP is an ABC transporter that plays an important role in tissue protection by exporting endogenous substrates and xenobiotics. ABCG2 is of major interest due to its involvement in multidrug resistance (MDR), and understanding its complex efflux mechanism is essential to preventing MDR and drug-drug interactions (DDI). ABCG2 export is characterized by two major conformational transitions between inward- and outward-facing states, the structures of which have been resolved. Yet, the entire transport cycle has not been characterized to date. Our study bridges the gap between the two extreme conformations by studying connecting pathways. We developed an innovative approach to enhance molecular dynamics simulations, 'kinetically excited targeted molecular dynamics', and successfully simulated the transitions between inward- and outward-facing states in both directions and the transport of the endogenous substrate estrone 3-sulfate. We discovered an additional pocket between the two substrate-binding cavities and found that the presence of the substrate in the first cavity is essential to couple the movements between the nucleotide-binding and transmembrane domains. Our study shed new light on the complex efflux mechanism, and we provided transition pathways that can help to identify novel substrates and inhibitors of ABCG2 and probe new drug candidates for MDR and DDI.

12.
J Cutan Pathol ; 36(12): 1316-22, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19602066

RESUMEN

Angiolymphoid hyperplasia with eosinophilia (ALHE) is a benign, uncommon idiopathic condition, characterized by cutaneous papules or nodules, whose etiopathogenesis is still unclear. It has been considered an angioproliferating lesion (epithelioid hemangioma) since histologically it is marked by a proliferation of blood vessels, accompanied by an inflammatory infiltrate, consisting mainly of lymphocytes and eosinophils. We present a case of ALHE assessed immunohistochemically for D2-40-a new marker for lymphatic endothelial cells. A biopsy specimen obtained from the same anatomical area of a healthy individual served as a normal control. The ALHE specimen showed increased number of lymphatic vessels when stained for D2-40, whereas the endothelial cells lining blood vessels were negative. The specificity of D2-40 for lymphatic vessels was further substantiated by studying Factor VIII-related antigen expression in consecutive sections of both ALHE and the control specimen. A reverse pattern was appreciated-blood vessels showed Factor VIII positive labeling, whereas lymphatic endothelial cells remained unlabeled. We therefore assume that apart from the lymphocytic infiltrate in the lesion, the recognized lymphoid component in ALHE is due to lymphatic vessel proliferation as well. Hence, this condition may be considered as possibly derived from lymphatic endothelium.


Asunto(s)
Anticuerpos Monoclonales , Células Endoteliales/patología , Enfermedades de los Labios/patología , Vasos Linfáticos/patología , Anciano , Hiperplasia Angiolinfoide con Eosinofilia/metabolismo , Hiperplasia Angiolinfoide con Eosinofilia/patología , Anticuerpos Monoclonales de Origen Murino , Células Endoteliales/metabolismo , Femenino , Humanos , Enfermedades de los Labios/metabolismo , Vasos Linfáticos/metabolismo
13.
Nucleic Acids Res ; 35(Web Server issue): W568-72, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17485475

RESUMEN

In silico screening methods based on the 3D structures of the ligands or of the proteins have become an essential tool to facilitate the drug discovery process. To achieve such process, the 3D structures of the small chemical compounds have to be generated. In addition, for ligand-based screening computations or hierarchical structure-based screening projects involving a rigid-body docking step, it is necessary to generate multi-conformer 3D models for each input ligand to increase the efficiency of the search. However, most academic or commercial compound collections are delivered in 1D SMILES (simplified molecular input line entry system) format or in 2D SDF (structure data file), highlighting the need for free 1D/2D to 3D structure generators. Frog is an on-line service aimed at generating 3D conformations for drug-like compounds starting from their 1D or 2D descriptions. Given the atomic constitution of the molecules and connectivity information, Frog can identify the different unambiguous isomers corresponding to each compound, and generate single or multiple low-to-medium energy 3D conformations, using an assembly process that does not presently consider ring flexibility. Tests show that Frog is able to generate bioactive conformations close to those observed in crystallographic complexes. Frog can be accessed at http://bioserv.rpbs.jussieu.fr/Frog.html.


Asunto(s)
Biología Computacional/métodos , Cristalografía por Rayos X/métodos , Estructura Molecular , Proteínas/química , Algoritmos , Química/métodos , Química Farmacéutica/métodos , Simulación por Computador , Bases de Datos de Proteínas , Ligandos , Modelos Químicos , Conformación Molecular , Docilidad , Relación Estructura-Actividad Cuantitativa , Programas Informáticos
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