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1.
Int J Cosmet Sci ; 40(5): 516-524, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30222197

RESUMO

OBJECTIVE: Hair greying (i.e., canities) is a component of chronological ageing and occurs regardless of gender or ethnicity. Canities is directly linked to the loss of melanin and increase in oxidative stress in the hair follicle and shaft. To promote hair pigmentation and reduce the hair greying process, an agonist of α-melanocyte-stimulating hormone (α-MSH), a biomimetic peptide (palmitoyl tetrapeptide-20; PTP20) was developed. The aim of this study was to describe the effects of the designed peptide on hair greying. METHODS: Effect of the PTP20 on the enzymatic activity of catalase and the production of H2 O2 by Human Follicle Dermal Papilla Cells (HFDPC) was evaluated. Influence of PTP20 on the expression of melanocortin receptor-1 (MC1-R) and the production of melanin were investigated. Enzymatic activity of sirtuin 1 (SIRT1) after treatment with PTP20 was also determined. Ex vivo studies using human micro-dissected hairs allowed to visualize the effect of PTP20 on the expression in hair follicle of catalase, TRP-1, TRP-2, Melan-A, ASIP, and MC1-R. These investigations were completed by a clinical study on 15 human male volunteers suffering from premature canities. RESULTS: The in vitro and ex vivo studies revealed the capacity of the examined PTP20 peptide to enhance the expression of catalase and to decrease (30%) the intracellular level of H2 O2 . Moreover, PTP20 was shown to activate in vitro and ex vivo the melanogenesis process. In fact, an increase in the production of melanin was shown to be correlated with elevated expression of MC1-R, TRP-1, and Melan-A, and with the reduction in ASIP expression. A modulation on TRP-2 was also observed. The pivotal role of MC1-R was confirmed on protein expression analysed on volunteer's plucked hairs after 3 months of the daily application of lotion containing 10 ppm of PTP20 peptide. CONCLUSION: The current findings demonstrate the ability of the biomimetic PTP20 peptide to preserve the function of follicular melanocytes. The present results suggest potential cosmetic application of this newly designed agonist of α-MSH to promote hair pigmentation and thus, reduce the hair greying process.


Assuntos
Envelhecimento , Cor de Cabelo/efeitos dos fármacos , Oligopeptídeos/farmacologia , alfa-MSH/agonistas , Adolescente , Adulto , Idoso , Catalase/metabolismo , Células Cultivadas , Feminino , Células HEK293 , Folículo Piloso/enzimologia , Folículo Piloso/metabolismo , Humanos , Masculino , Receptor Tipo 1 de Melanocortina/genética , Sirtuína 1/metabolismo , Ativação Transcricional , Adulto Jovem
2.
Br J Dermatol ; 177(5): 1322-1336, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28403520

RESUMO

BACKGROUND: Male androgenetic alopecia (AGA) is the most common form of hair loss in men. It is characterized by a distinct pattern of progressive hair loss starting from the frontal area and the vertex of the scalp. Although several genetic risk loci have been identified, relevant genes for AGA remain to be defined. OBJECTIVES: To identify biomarkers associated with AGA. METHODS: Molecular biomarkers associated with premature AGA were identified through gene expression analysis using cDNA generated from scalp vertex biopsies of hairless or bald men with premature AGA, and healthy volunteers. RESULTS: This monocentric study reveals that genes encoding mast cell granule enzymes, inflammatory mediators and immunoglobulin-associated immune mediators were significantly overexpressed in AGA. In contrast, underexpressed genes appear to be associated with the Wnt/ß-catenin and bone morphogenic protein/transforming growth factor-ß signalling pathways. Although involvement of these pathways in hair follicle regeneration is well described, functional interpretation of the transcriptomic data highlights different events that account for their inhibition. In particular, one of these events depends on the dysregulated expression of proopiomelanocortin, as confirmed by polymerase chain reaction and immunohistochemistry. In addition, lower expression of CYP27B1 in patients with AGA supports the notion that changes in vitamin D metabolism contributes to hair loss. CONCLUSIONS: This study provides compelling evidence for distinct molecular events contributing to alopecia that may pave the way for new therapeutic approaches.


Assuntos
Alopecia/genética , Transdução de Sinais/genética , 25-Hidroxivitamina D3 1-alfa-Hidroxilase/metabolismo , Adulto , Análise de Variância , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Estudos de Casos e Controles , Cateninas/genética , DNA Complementar/genética , Regulação para Baixo/genética , Expressão Gênica/genética , Perfilação da Expressão Gênica/métodos , Marcadores Genéticos , Folículo Piloso/metabolismo , Humanos , Masculino , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Regulação para Cima/genética , Vitamina D/genética , Vitamina D/metabolismo , Via de Sinalização Wnt/genética
7.
Ann Endocrinol (Paris) ; 66(2 Pt 1): 121-4, 2005 Apr.
Artigo em Francês | MEDLINE | ID: mdl-15959413

RESUMO

We report the case of an 11-year-old child with delayed development who developed signs of exercise-induced pain in the lower limb muscles after an acute attack of appendicitis. He had difficulty standing up from the sitting position and ascending and descending stairs. The physical examination revealed increased reflex activity in the lower limbs. Initially, blood tests, MRI and EMG were normal. Serum phosphorus and calcium were not assayed. Eight months later, the boy's condition worsened (myopathy gait, hyperlordosis) leading to the possible diagnosis of muscle disease. After muscle biopsy, blood tests revealed hypercalcemia at 3.5 mmol/l (normal 2.2-2.6), hypercalciuria, and hypophosporemia. The diagnosis of primary hyperparathyroidism was confirmed by the abnormal level of parathormone initially (19 ng/ml) and later (156 ng/ml) with hypercalcemia. Medical treatment failed and surgery was performed to remove three and a half parathyroid glands. After removal, blood tests returned to normal in six days and the physical examination in three years. The diagnosis of principal cell hyperplasia was retained at the pathology examination. We found no evidence of hypercalcemia or other endocrinopathy such as multiple endocrine neoplasia (MEN 1 or 2a). Study of the menine gene did not reveal any mutation. Muscle dysfunction suggest possible abnormal phosphocalcium regulation. A normal parathormone level with hypercalcemia reveals inappropriate synthesis and secretion.


Assuntos
Hiperparatireoidismo/diagnóstico , Doenças Musculares/etiologia , Criança , Exercício Físico , Humanos , Hipercalcemia , Hiperparatireoidismo/complicações , Hiperparatireoidismo/cirurgia , Masculino , Dor , Hormônio Paratireóideo/sangue
10.
Ann Endocrinol (Paris) ; 65(2): 125-30, 2004 Apr.
Artigo em Francês | MEDLINE | ID: mdl-15247872

RESUMO

Two of every thousand pregnancies are complicated by Graves' disease. Diagnosis is suggested by maternal disorders (tachycardia, exophthalmia, weight loss.) or fetal disorders (tachycardia, intra-uterine growth retardation, preterm birth.). Due to transfer into the fetal compartment of maternal antibodies which stimulate the fetal thyroid by binding to the thyroid thyrotropin (TSH) receptor, only 1% of children born to these mothers are described as having hyperthyroidism. Neonatal thyrotoxicosis disappears with clearance of the maternal antibodies; clinical signs usually disappear during the first four Months of life. The most frequent neonatal clinical signs of thyrotoxicosis are tachycardia, goiter, hyperexcitability, poor weight gain, hepatosplenomegaly, stare and eyelid retraction. Diagnosis is based on determination of the blood level of triiodothyronine (T3), thyroxine (T4) and TSH. To confirm the nature of hyperthyroidism, thyroid-stimulating immunoglobulins (TSI) should be assayed. The kinetics of TSI provides a guide for therapeutic adaptation and disappearance of TSI is a sign of recovery. Rare cases of familial non-autoimmune hyperthyroidism have been shown to be caused by germline mutation of the thyrotropin receptor. We report a case of severe neonatal hyperthyroidism which led to the diagnosis of maternal Graves' disease.


Assuntos
Doença de Graves/fisiopatologia , Hipertireoidismo/congênito , Hipertireoidismo/etiologia , Complicações na Gravidez/fisiopatologia , Antitireóideos/uso terapêutico , Carbimazol/uso terapêutico , Feminino , Humanos , Hipertireoidismo/tratamento farmacológico , Recém-Nascido , Gravidez
18.
Arch Pediatr ; 5(8): 869-72, 1998 Aug.
Artigo em Francês | MEDLINE | ID: mdl-9759292

RESUMO

AIM: Because there are few adoptable children in France, parents, for the last 20 years, have turned to international adoption. Alerted by the generally poor health of these children, we paid particular attention to their health problems and especially to infection by hepatitis B virus (HBV). POPULATION AND METHODS: The 60 internationally-adopted children seen from June 1993 to June 1997 were included in this study. All had hemogram and serum iron dosage, and search for intestinal parasites and tuberculosis was performed in each child, as were HBs antigen and HBs antibody screening. When HBs antigen was positive, HBe antigen and antibodies, HBV DNA and hepatitis C and delta serology were also studied. RESULTS: Six out of the 60 children were HBV chronic carriers. The six presented HBs antigen and five out of the six presented viral DNA. One child was co-infected with delta virus. Serum aminotransferase was normal in three children and increased in the three others. DISCUSSION: Some internationally adopted children are exposed to chronic infection by HBV. This concerns children coming from countries known for the high frequency of the disease, but also children with long stay in Eastern European nurseries. Chronic HBV carriage puts the child, as well as the family and other children in institutions and/or schools at risk, thus necessitating preventive measures.


Assuntos
Adoção , Portador Sadio/epidemiologia , Países em Desenvolvimento , Hepatite B Crônica/epidemiologia , Portador Sadio/diagnóstico , Criança , Pré-Escolar , Feminino , França , Hepatite B Crônica/diagnóstico , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/epidemiologia , Hepatite D/diagnóstico , Hepatite D/epidemiologia , Humanos , Lactente , Masculino , Programas de Rastreamento
19.
Arch Pediatr ; 5(1): 19-23, 1998 Jan.
Artigo em Francês | MEDLINE | ID: mdl-10223106

RESUMO

BACKGROUND: Idiopathic thrombocytopenic purpura (ITP) has usually an excellent prognosis even when no specific therapy is given. We studied, in 1996, the outcome of 87 patients with ITP observed between 1973 and 1995. PATIENTS AND METHODS: These 87 cases represented all the thrombocytopenic purpura observed during 23 years in the same pediatric unit not specialized in hematology. The outcome of these children was investigated in 1996 by phone or writing to the patients themselves or to their physician. Adequate information was obtained for 63 patients (72.4%). RESULTS: Two cerebral hemorrhages were observed, one was lethal while the other, observed after several years of course, healed completely. All these patients became free from clinical signs but 11 were not cured in 1996. None of these 63 patients had developed autoimmune disease. One patient died in a traffic accident, his thrombocytopenic purpura had been cured. CONCLUSION: In spite of two cerebral hemorrhages, ITP remains in the great majority of cases a benign disease not requiring grave therapeutic decisions.


Assuntos
Púrpura Trombocitopênica/fisiopatologia , Adolescente , Idade de Início , Doenças Autoimunes/complicações , Hemorragia Cerebral/complicações , Hemorragia Cerebral/epidemiologia , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Masculino , Púrpura Trombocitopênica/complicações , Estudos Retrospectivos , Fatores de Tempo
20.
Arch Pediatr ; 3(8): 789-91, 1996 Aug.
Artigo em Francês | MEDLINE | ID: mdl-8998533

RESUMO

BACKGROUND: The previously reported cases of giant cell hepatitis with autoimmune hemolytic anemia were improved by prednisone plus azathioprine. CASE REPORT: A 14-month-old boy suffered from giant cell hepatitis with auto-immune hemolytic anemia and positive direct Coombs test. Prednisone and azathioprine administration improved the liver disease but failed to control hemolysis so that repeated blood transfusions were necessary. Persistance of severe degree of hemolysis required splenectomy that was promptly and definitively effective. Azathioprine and prednisone were pursued for a total duration of five years. Twelve years after the onset of the disease, the child is well without any treatment. CONCLUSION: This is the first reported case of such an association in which poorly controlled auto-immune hemolytic anemia benefited from splenectomy.


Assuntos
Anemia Hemolítica Autoimune/complicações , Hepatite/complicações , Anemia Hemolítica Autoimune/terapia , Azatioprina/administração & dosagem , Terapia Combinada , Quimioterapia Combinada , Hemólise , Hepatite/patologia , Hepatite/cirurgia , Humanos , Lactente , Fígado/patologia , Masculino , Prednisona/administração & dosagem , Esplenectomia
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