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1.
Dermatology ; : 1-7, 2022 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-35512658

RESUMEN

BACKGROUND: Ex vivo confocal microscopy using fusion mode and digital staining (EVCM) scans unfixed fresh tissue and produces rapidly digitally stained images of very similar quality to classical pathology. We investigated whether EVCM could represent an alternative to the standard histological examination of the pretherapeutic basal cell carcinoma (BCC) punch biopsies. OBJECTIVES: The objective of the study was to assess diagnostic accuracy of EVCM versus traditional histopathological examination for diagnosing and subtyping clinically suspicious lesions of BCC in 3-mm fresh and nonfixed punch biopsies. METHODS: In this prospective monocentric observational study, patients with clinically suspected BCC were consecutively enrolled. Punch biopsies were imaged using EVCM and subsequently processed for standard histologic examination (gold standard). EVCM images were examined by a dermatopathologist blinded to clinical aspect of the lesion and histopathological results. Concordance between the EVCM and histology analysis was calculated with Cohen's kappa (κ) statistic. RESULTS: Sixty-six patients were recruited, and 106 biopsies were analyzed. EVCM correctly diagnosed 70/73 BCCs and 31/33 non-BCC lesions, corresponding to a sensitivity of 96% and a specificity of 94% (positive predictive value = 97%, negative predictive value = 91%). The EVCM assessment led to over-staging and under-staging of BCC subtypes in 5% and 11% of cases, respectively. It led to over-staging and under-staging of BCC depths in 5% and 15%, respectively. The kappa coefficient for concordance was 0.78 (95% confidence interval [CI]: 0.69-0.88) when considering BCC subtypes and 0.81 (95% CI: 0.72-0.90) when considering BCC depths. CONCLUSIONS: These results render EVCM as a promising option for "real-time" pretreatment evaluation of clinically suspected BCC lesions. Further larger randomized studies are needed to assess the efficiency of EVCM versus standard care in patients with clinically suspected BCC.

4.
Dermatology ; 228(2): 103-6, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24334907

RESUMEN

BACKGROUND: Macular arteritis, macular lymphocytic arteritis (MLA) or lymphocytic thrombophilic arteritis all correspond to an identical new clinicopathological entity. Its individualization as a primary cutaneous lymphocytic arteritis is still controversial for certain authors as it could represent a latent form of cutaneous polyarteritis nodosa. MATERIALS AND METHODS: We report here 3 additional cases of MLA, present a review of the literature and discuss the disease's nosology. RESULTS: MLA is characterized clinically by a benign skin eruption consisting in bilateral asymptomatic erythematous/hyperpigmented macules mainly located on the lower legs and histologically by a medium-sized cutaneous lymphocytic prominent arteritis present in early cutaneous lesions. CONCLUSION: These findings support that MLA may be considered as a chronic and indolent primary lymphocytic cutaneous arteritis. Nevertheless, in some cases the objective obliteration of cutaneous vessels underlines the need for continuous monitoring in MLA patients.


Asunto(s)
Arteritis/patología , Hiperpigmentación/patología , Linfocitos , Adulto , Arteritis/clasificación , Arteritis/inmunología , Diagnóstico Diferencial , Femenino , Humanos , Hiperpigmentación/inmunología , Pierna/patología , Linfocitos/inmunología , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Enfermedades Cutáneas Vasculares/patología
5.
Melanoma Res ; 34(3): 241-247, 2024 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-38546723

RESUMEN

Although current systemic therapies significantly improved the outcome of advanced melanoma, the prognosis of patient with central nervous system (CNS) metastases remains poor especially when clinically symptomatic. We aimed to investigate the efficiency of CNS targets and tolerance of second-line combined anti-PD1/dual-targeted anti-BRAF/anti-MEK therapy implemented in patients with CNS progression after initially efficient first-line combined targeted therapy in patients with BRAF-mutated melanoma in a real-life setting. A monocentric retrospective analysis including all such patients treated from January 2017 to January 2022 was conducted in our tertiary referral center. The response of CNS lesions to second-line triple therapy was assessed through monthly clinical and at least quarterly morphological (according to RECIST criteria) evaluation. Tolerance data were also collected. Seventeen patients were included with a mean follow-up of 2.59 (±2.43) months. Only 1 patient displayed a significant clinical and morphological response. No statistically significant difference was observed between patients receiving or not additional local therapy (mainly radiotherapy) as to response achievement. Immunotherapy was permanently discontinued in 1 patient owing to grade 4 toxicity. Mean PFS and OS after CNS progression were 2.59 and 4.12 months, respectively. In this real-life survey, the subsequent addition of anti-PD1 to combined targeted therapy in melanoma patients with upfront CNS metastases did not result in significant response of CNS targets in most BRAF mutated melanoma patients with secondary CNS progression after initially successful first-line combined targeted therapy.


Asunto(s)
Neoplasias del Sistema Nervioso Central , Melanoma , Proteínas Proto-Oncogénicas B-raf , Neoplasias Cutáneas , Humanos , Melanoma/tratamiento farmacológico , Melanoma/genética , Melanoma/patología , Femenino , Masculino , Proteínas Proto-Oncogénicas B-raf/genética , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Neoplasias del Sistema Nervioso Central/secundario , Neoplasias del Sistema Nervioso Central/tratamiento farmacológico , Adulto , Neoplasias Cutáneas/tratamiento farmacológico , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Inhibidores de Proteínas Quinasas/uso terapéutico , Inhibidores de Proteínas Quinasas/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inhibidores de Puntos de Control Inmunológico/farmacología , Mutación , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Anciano de 80 o más Años
6.
Int J Cancer ; 133(1): 142-8, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23238767

RESUMEN

Plasmatic proteasome (p-proteasome) has recently been described as a new marker for metastatic melanoma. The objective of this study was to compare the diagnostic and prognostic values of p-proteasome with three other melanoma serological markers: S100B protein, melanoma inhibitory activity protein (MIA) and lactate dehydrogenase (LDH) in the plasma of 121 stage I-IV melanoma patients. Laboratory analyses were performed by standardized ELISA (p-proteasome, MIA), immunoluminometric assay (S100B) and colorimetry (LDH). We found that all markers were relevant for discriminating metastatic from nonmetastatic patients but p-proteasome displayed the highest diagnostic accuracy. P-proteasome and S100B were the most sensitive (58.1%) and p-proteasome and MIA the most specific (98.7 and 100%) in detecting metastatic disease. P-proteasome and S100B had the highest area under receiver operating characteristics curve, 0.811 (95% CI: 0.725-0.897) and 0.822 (95% CI: 0.738-0.906), respectively. These two markers were the best in detecting patients with lymph node metastases. S100B, MIA and LDH diagnostic accuracy was increased when these markers were combined with p-proteasome. As shown with univariate analysis, shorter progression-free and overall survival rates were significantly associated with elevated plasma levels of each markers. The multivariate Cox regression analysis identified p-proteasome as the only independent predictor of a poorer progression-free survival (p = 0.030). In conclusion, this comparative study established that p-proteasome quantification in combination with other melanoma biomarkers is an attractive approach for the biological follow-up of melanoma patients.


Asunto(s)
Biomarcadores de Tumor/sangre , Proteínas de la Matriz Extracelular/sangre , L-Lactato Deshidrogenasa/sangre , Melanoma/diagnóstico , Proteínas de Neoplasias/sangre , Factores de Crecimiento Nervioso/sangre , Complejo de la Endopetidasa Proteasomal/sangre , Proteínas S100/sangre , Neoplasias Cutáneas/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Colorimetría , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Estimación de Kaplan-Meier , Metástasis Linfática , Masculino , Melanoma/sangre , Melanoma/secundario , Persona de Mediana Edad , Estadificación de Neoplasias , Plasma , Valor Predictivo de las Pruebas , Pronóstico , Modelos de Riesgos Proporcionales , Subunidad beta de la Proteína de Unión al Calcio S100 , Neoplasias Cutáneas/sangre , Neoplasias Cutáneas/patología
7.
J Am Acad Dermatol ; 69(5): 768-775, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23972508

RESUMEN

BACKGROUND: Children with multiple café-au-lait macules (CALMs) may be followed for years before a second National Institutes of Health clinical criterion of neurofibromatosis type 1 (NF1) develops to confirm the diagnosis. OBJECTIVE: We sought to assess the prevalence of nevus anemicus (NA) in NF1 and its association with neuro-ophthalmologic complications. METHODS: This was a prospective multicenter case-control study of 210 consecutive patients with multiple CALMs. Patients with NF1 were matched for age, sex, and center with control subjects. We documented the number, location, and morphologic appearance of NA; dermatologic features of NF1; magnetic resonance imaging results; and family history. RESULTS: In all, 77 (51%) patients with NF1 had NA compared with 6 (2%) control subjects. NA was not detected in 26 patients with other genodermatoses associated with CALMs. Patients with NF1 and NA were younger than those without NA (median age: 17 years) (P = .002). NA was mostly localized to the upper anterior aspect of the chest. NA was not significantly linked with other clinical manifestations of NF1, including optic glioma and unidentified bright objects. LIMITATIONS: A potential referral bias associated with tertiary care centers is a limitation. CONCLUSIONS: NA appears to have a high prevalence and specificity in NF1 and might serve as a marker for NF1 in children with multiple CALMs.


Asunto(s)
Neurofibromatosis 1/complicaciones , Neurofibromatosis 1/diagnóstico , Nevo/etiología , Trastornos de la Pigmentación/etiología , Neoplasias Cutáneas/etiología , Adolescente , Adulto , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Humanos , Masculino , Estudios Prospectivos , Adulto Joven
8.
Int Wound J ; 10(5): 539-41, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22712583

RESUMEN

Pseudoepitheliomatous hyperplasia is a benign condition defined by an exuberant proliferation of the epithelium with downward progression into the dermis. It may occur in reaction to several conditions including chronic cutaneous wound. We describe an unusual case of a florid pseudoepitheliomatous hyperplasia mimicking a well-differentiated squamous cell carcinoma, restricted to the red part of a rose tattoo.


Asunto(s)
Enfermedades de la Piel/etiología , Tatuaje/efectos adversos , Biopsia , Diagnóstico Diferencial , Femenino , Humanos , Hiperplasia/etiología , Hiperplasia/patología , Hiperplasia/cirugía , Persona de Mediana Edad , Enfermedades de la Piel/patología , Enfermedades de la Piel/cirugía
9.
J Cell Physiol ; 227(6): 2578-85, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21898403

RESUMEN

Ultraviolet A (UVA) radiations are responsible for deleterious effects, mainly due to reactive oxygen species (ROS) production. Alpha-melanocyte stimulating hormone (α-MSH) binds to melanocortin-1 receptor (MC1R) in melanocytes to stimulate pigmentation and modulate cutaneous inflammatory responses. MC1R may be induced in keratinocytes after UV exposure. To investigate the effect of MC1R signaling on UVA-induced ROS (UVA-ROS) production, we generated HaCaT cells that stably express human MC1R (HaCaT-MC1R) or the Arg151Cys (R(151)C) non-functional variant (HaCaT-R(151)C). We then assessed ROS production immediately after UVA exposure and found that: (1) UVA-ROS production was strongly reduced in HaCaT-MC1R but not in HaCaT-R(151)C cells compared to parental HaCaT cells; (2) this inhibitory effect was further amplified by incubation of HaCaT-MC1R cells with α-MSH before UVA exposure; (3) protein kinase A (PKA)-dependent NoxA1 phosphorylation was increased in HaCaT-MC1R compared to HaCaT and HaCaT-R(151)C cells. Inhibition of PKA in HaCaT-MC1R cells resulted in a marked increase of ROS production after UVA irradiation; (4) the ability of HaCaT-MC1R cells to produce UVA-ROS was restored by inhibiting epidermal growth factor receptor (EGFR) or extracellular signal-regulated kinases (ERK) activity before UVA exposure. Our findings suggest that constitutive activity of MC1R in keratinocytes may reduce UVA-induced oxidative stress via EGFR and cAMP-dependent mechanisms.


Asunto(s)
AMP Cíclico/metabolismo , Queratinocitos/efectos de la radiación , NADPH Oxidasas/metabolismo , Estrés Oxidativo/efectos de la radiación , Especies Reactivas de Oxígeno/metabolismo , Receptor de Melanocortina Tipo 1/metabolismo , Rayos Ultravioleta , Proteínas Adaptadoras Transductoras de Señales , Proteínas Adaptadoras del Transporte Vesicular/metabolismo , Línea Celular , Proteínas Quinasas Dependientes de AMP Cíclico/antagonistas & inhibidores , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Relación Dosis-Respuesta en la Radiación , Receptores ErbB/antagonistas & inhibidores , Receptores ErbB/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Humanos , Queratinocitos/efectos de los fármacos , Queratinocitos/enzimología , Estrés Oxidativo/efectos de los fármacos , Fosforilación , Inhibidores de Proteínas Quinasas/farmacología , Receptor de Melanocortina Tipo 1/genética , Transducción de Señal/efectos de la radiación , Factores de Tiempo , Transfección , alfa-MSH/metabolismo
10.
Proc Natl Acad Sci U S A ; 106(40): 17013-8, 2009 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-19805157

RESUMEN

Plasma cells can synthesize and secrete thousands of Ig molecules per second, which are folded and assembled in the endoplasmic reticulum (ER) and are likely to place unusually high demands on the resident chaperones and folding enzymes. We have discovered a new resident ER protein (pERp1) that is a component of the BiP chaperone complex. PERp1 is substantially up-regulated during B to plasma cell differentiation and can be induced in B cell lines by some UPR activators, arguing that it represents a potentially new class of conditional UPR targets. In LPS-stimulated murine splenocytes, pERp1 interacted covalently via a disulfide bond with IgM monomers and noncovalently with other Ig assembly intermediates. Knockdown and overexpression experiments revealed that pERp1 promoted correct oxidative folding of Ig heavy chains and prevented off-pathway assembly intermediates. Although pERp1 has no homology with known chaperones or folding enzymes, it possesses a thioredoxin-like active site motif (CXXC), which is the signature of oxidoreductases. Mutation of this sequence did not affect its in vivo activity, suggesting that pERp1 is either a unique type of oxidoreductase or a previously unidentified class of molecular chaperone that is dedicated to enhancing the oxidative folding of Ig precursors.


Asunto(s)
Retículo Endoplásmico/metabolismo , Inmunoglobulinas/metabolismo , Chaperonas Moleculares/metabolismo , Células Plasmáticas/metabolismo , Secuencia de Aminoácidos , Animales , Linfocitos B/citología , Linfocitos B/metabolismo , Células de la Médula Ósea/citología , Células de la Médula Ósea/metabolismo , Diferenciación Celular , Línea Celular , Línea Celular Tumoral , Células Cultivadas , Chaperón BiP del Retículo Endoplásmico , Femenino , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Immunoblotting , Inmunoglobulinas/química , Ratones , Ratones Endogámicos C57BL , Chaperonas Moleculares/genética , Datos de Secuencia Molecular , Mutación , Oxidación-Reducción , Células Plasmáticas/citología , Pliegue de Proteína , Interferencia de ARN , Homología de Secuencia de Aminoácido , Regulación hacia Arriba
11.
Exp Dermatol ; 19(12): 1054-9, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20707810

RESUMEN

Plasmatic proteasome (p-proteasome) also called circulating proteasome has recently been described as a tumor marker. We investigated the diagnostic and prognostic accuracies of p-proteasome levels in a melanoma population classified according to the American Joint Committee on Cancer staging system. Using an ELISA test, we measured p-proteasome levels in 90 patients and 40 controls between March 2003 and March 2008. The subunit composition of p-proteasomes was determined in metastatic melanoma by proteomic analysis. The mean p-proteasome levels were correlated with stages (P < 0.0001; r(S) = 0.664). They were significantly higher in patients with stage IV and stage III with lymph node metastasis (9187 ± 1294 and 5091 ± 454 ng/ml, respectively) compared to controls (2535 ± 187 ng/ml; P < 0.001), to stage I/II (2864 ± 166 ng/ml; P < 0.001) and to stage III after curative lymphadenectomy (2859 ± 271 ng/ml; P < 0.001). The diagnostic accuracy of p-proteasome was evaluated by receiver operating characteristic analysis. With a cut-off of 4300 ng/ml, diagnostic specificity and sensitivity of p-proteasome for regional or visceral metastases were respectively 96.3% and 72.2%. In univariate analysis, high p-proteasome levels (>4300 ng/ml) were significantly correlated with an increased risk of progression [hazard ratio (HR) = 7.34; 95% CI 3.54-15.21, P < 0.0001] and a risk of death (HR = 5.92; 95% CI 2.84-12.33, P < 0.0001). In multivariate analysis, high p-proteasome levels were correlated with a poorer clinical outcome in the subgroup analysis limited to patients with disease stages I, II and III. Proteomic analysis confirmed the presence of all proteasome and immunoproteasome subunits. Taken together, these results indicate that p-proteasomes are a new marker for metastatic dissemination in patients with melanoma.


Asunto(s)
Melanoma/sangre , Melanoma/diagnóstico , Complejo de la Endopetidasa Proteasomal/sangre , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Supervivencia sin Enfermedad , Femenino , Humanos , L-Lactato Deshidrogenasa/sangre , Masculino , Melanoma/patología , Persona de Mediana Edad , Metástasis de la Neoplasia/diagnóstico , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Pronóstico , Subunidades de Proteína/sangre , Curva ROC , Recurrencia , Análisis de Supervivencia , Adulto Joven
12.
Cancers (Basel) ; 12(4)2020 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-32295074

RESUMEN

Melanoma and Merkel cell carcinoma are two aggressive skin malignancies with high disease-related mortality and increasing incidence rates. Currently, invasive tumor tissue biopsy is the gold standard for their diagnosis, and no reliable easily accessible biomarker is available to monitor patients with melanoma or Merkel cell carcinoma during the disease course. In these last years, liquid biopsy has emerged as a candidate approach to overcome this limit and to identify biomarkers for early cancer diagnosis, prognosis, therapeutic response prediction, and patient follow-up. Liquid biopsy is a blood-based non-invasive procedure that allows the sequential analysis of circulating tumor cells, circulating cell-free and tumor DNA, and extracellular vesicles. These innovative biosources show similar features as the primary tumor from where they originated and represent an alternative to invasive solid tumor biopsy. In this review, the biology and technical challenges linked to the detection and analysis of the different circulating candidate biomarkers for melanoma and Merkel cell carcinoma are discussed as well as their clinical relevance.

13.
Cells ; 8(7)2019 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-31330795

RESUMEN

Metastatic melanoma is one of the most aggressive and drug-resistant cancers with very poor overall survival. Circulating melanoma cells (CMCs) were first described in 1991. However, there is no general consensus on the clinical utility of CMC detection, largely due to conflicting results linked to the use of heterogeneous patient populations and different detection methods. Here, we developed a new EPithelial ImmunoSPOT (EPISPOT) assay to detect viable CMCs based on their secretion of the S100 protein (S100-EPISPOT). Then, we compared the results obtained with the S100-EPISPOT assay and the CellSearch® CMC kit using blood samples from a homogeneous population of patients with metastatic melanoma. We found that S100-EPISPOT sensitivity was significantly higher than that of CellSearch®. Specifically, the percentage of patients with ≥2 CMCs was significantly higher using S100-EPISPOT than CellSearch® (48% and 21%, respectively; p = 0.0114). Concerning CMC prognostic value, only the CellSearch® results showed a significant association with overall survival (p = 0.006). However, due to the higher sensitivity of the new S100-EPISPOT assay, it would be interesting to determine whether this functional test could be used in patients with non-metastatic melanoma for the early detection of tumor relapse and for monitoring the treatment response.


Asunto(s)
Melanoma/sangre , Células Neoplásicas Circulantes/metabolismo , Programas Informáticos , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Femenino , Humanos , Masculino , Melanoma/patología , Persona de Mediana Edad , Técnicas de Diagnóstico Molecular/métodos , Proteínas S100/genética , Proteínas S100/metabolismo
14.
Exp Dermatol ; 17(11): 908-15, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18341568

RESUMEN

Thymidine phosphorylase (TP)/platelet-derived endothelial cell growth factor is associated with tumor angiogenesis. We evaluated the TP mRNA and protein expression in basal cell carcinomas (BCC) and in various skin tumors including numerous BCC histological simulants. Immunohistochemistry was performed on 99 paraffin sections of formalin-fixed skin tumors using monoclonal antibodies (mAb) against TP. TP mRNA levels were measured by real time RT-PCR in whole BCCs (wBCC) and laser capture microdissected (LCM) BCC tumor cells. TP immunostaining was negative in all BCC variants and in most of the benign trichogeneic tumors studied. By contrast, TP was constantly immunodetected in actinic keratosis (AK), squamous cell carcinomas (SCC), syringomatous carcinomas (SC), basosquamous carcinomas (BSC) and melanomas. TP mRNA levels were low and statistically not different in wBCC and normal skin but were strongly downregulated in LCM-BCC as compared with LCM-normal epidermis. We concluded that (i) anti-TP mAb is an useful marker to differentiate BCC from AK, SCC, BSC and SC but not from trichoblastic tumors, (ii) the lack of TP protein expression in BCC tumoral cells is linked to transcriptional regulatory mechanisms, (iii) the low TP mRNA levels in whole BCC may be related to the low intra-tumoral microvessel density, the slow growth and the very low metastatic potential of these tumors.


Asunto(s)
Carcinoma Basocelular/patología , Neoplasias Cutáneas/patología , Timidina Fosforilasa/genética , Carcinoma Basocelular/genética , Carcinoma Basocelular/metabolismo , Carcinoma Basoescamoso/genética , Carcinoma Basoescamoso/metabolismo , Carcinoma Basoescamoso/patología , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Queratosis Actínica/genética , Queratosis Actínica/metabolismo , Queratosis Actínica/patología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/metabolismo , Timidina Fosforilasa/biosíntesis
15.
Part Fibre Toxicol ; 5: 20, 2008 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-19068117

RESUMEN

BACKGROUND: Constituted only by carbon atoms, CNT are hydrophobic and hardly detectable in biological tissues. These properties make biokinetics and toxicology studies more complex. METHODS: We propose here a method to investigate the biopersistence of CNT in organism, based on detection of nickel, a metal present in the MWCNT we investigated. RESULTS AND CONCLUSION: Our results in rats that received MWCNT by intratracheal instillation, reveal that MWCNT can be eliminated and do not significantly cross the pulmonary barrier but are still present in lungs 6 months after a unique instillation. MWCNT structure was also showed to be chemically modified and cleaved in the lung. These results provide the first data of CNT biopersistence and clearance at 6 months after respiratory administration.

17.
Mol Biol Cell ; 13(12): 4456-69, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12475965

RESUMEN

We demonstrate the existence of a large endoplasmic reticulum (ER)-localized multiprotein complex that is comprised of the molecular chaperones BiP; GRP94; CaBP1; protein disulfide isomerase (PDI); ERdj3, a recently identified ER Hsp40 cochaperone; cyclophilin B; ERp72; GRP170; UDP-glucosyltransferase; and SDF2-L1. This complex is associated with unassembled, incompletely folded immunoglobulin heavy chains. Except for ERdj3, and to a lesser extent PDI, this complex also forms in the absence of nascent protein synthesis and is found in a variety of cell types. Cross-linking studies reveal that the majority of these chaperones are included in the complex. Our data suggest that this subset of ER chaperones forms an ER network that can bind to unfolded protein substrates instead of existing as free pools that assembled onto substrate proteins. It is noticeable that most of the components of the calnexin/calreticulin system, which include some of the most abundant chaperones inside the ER, are either not detected in this complex or only very poorly represented. This study demonstrates an organization of ER chaperones and folding enzymes that has not been previously appreciated and suggests a spatial separation of the two chaperone systems that may account for the temporal interactions observed in other studies.


Asunto(s)
Retículo Endoplásmico/metabolismo , Secuencia de Aminoácidos , Animales , Western Blotting , Calnexina/metabolismo , Calreticulina/metabolismo , Núcleo Celular/metabolismo , Reactivos de Enlaces Cruzados/farmacología , Electroforesis en Gel Bidimensional , Retículo Endoplásmico/enzimología , Glicerol/metabolismo , Humanos , Espectrometría de Masas , Ratones , Datos de Secuencia Molecular , Unión Proteica , Pliegue de Proteína , Células Tumorales Cultivadas
18.
Ann Pathol ; 27(2): 74-9, 2007 Apr.
Artículo en Francés | MEDLINE | ID: mdl-17909459

RESUMEN

AIMS: The goal of this work was to assess the validity of Mohs Micrographic Surgery (MMS) for basal cell carcinoma (BCC) in a routine clinical setting. MATERIAL AND METHODS: Our adaptation of the technique described by Mohs and coll allows intraoperative histological examination of all surgical edges of the resection. Sixteen men and 4 women were selected. RESULTS: Average operative time was 2 hours 30 minutes. No false results were noted. The cosmetetic and functional outcomes were good. CONCLUSION: MMS is a safe and reproducible surgical technique made possible by solid team work. It is adapted for the treatment of BCC with a high risk of recurrence. The cosmetetic and functional results are quite satisfactory. The recurrence rate at 5 years is 10 times less than with other methods of treatment. The additional time required for this surgery be put in balance with the number of tumors for which a second intervention would have been necessary if conventional surgery had been used. All procedures were performed under local anesthesia, and none or the patients required a second intervention.


Asunto(s)
Carcinoma Basocelular/cirugía , Cirugía de Mohs , Neoplasias Cutáneas/cirugía , Anciano , Anciano de 80 o más Años , Carcinoma Basocelular/patología , Femenino , Francia , Hospitales Universitarios , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Cutáneas/patología
19.
J Dermatol Sci ; 88(1): 10-19, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28728908

RESUMEN

BACKGROUND: The ubiquitin proteasome pathway is involved in the pathogenesis of psoriasis and proteasome subunits are increased in lesional psoriatic skin. Recent works have highlighted that proteasome levels can be regulated through modulation of proteasome assembly notably by the proteasome maturation protein POMP. OBJECTIVES: To investigate whether proteasome assembly and POMP expression are modified in psoriatic skin. METHODS: Proteasome assembly as well as expression of proteasome regulators were assessed in non-lesional and lesional psoriatic skin using native gel electrophoresis and western blots respectively. The protein and mRNA expression levels of POMP were compared by western blots, immunohistochemistry and quantitative polymerase chain reaction. The role of POMP in keratinocyte proliferation and differentiation was assessed by silencing POMP gene expression by RNA interference in human immortalized keratinocyte HaCaT cells. RESULTS: Both 20S and 26S proteasomes (and their respective proteolytic activities) as well as the main proteasome regulators are increased in lesional psoriatic skin. POMP binds to 20S precursor complexes and is overexpressed in lesional epidermal psoriatic skin, supporting that POMP-mediated proteasome assembly is increased in psoriatic skin. POMP silencing inhibited HaCaT cell proliferation and induced apoptosis through the inhibition of the proteasome assembly. Moreover POMP partial depletion decreased the expression of the differentiation markers keratin 10 and involucrin during the [Ca2+]-induced HaCaT cells differentiation. CONCLUSION: Altogether these results establish a potential role for POMP and proteasome assembly in psoriasis pathogenesis.


Asunto(s)
Queratinocitos/patología , Chaperonas Moleculares/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Psoriasis/patología , ARN Mensajero/metabolismo , Apoptosis , Biopsia , Western Blotting , Diferenciación Celular , Línea Celular , Proliferación Celular , Citoplasma , Células Epidérmicas , Epidermis/patología , Humanos , Queratinocitos/metabolismo , Chaperonas Moleculares/genética , Electroforesis en Gel de Poliacrilamida Nativa , Interferencia de ARN , ARN Interferente Pequeño/metabolismo
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