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1.
Biochim Biophys Acta ; 1860(7): 1466-74, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27085704

RESUMO

BACKGROUND: The human lysine methyltransferase Smyd3, a member of the SET and MYND domain containing protein family, harbors methylation activity on both histone and non-histone targets in a tightly regulated manner. The mechanism of how Smyd3 dynamically regulates substrate recognition is still not fully unveiled. METHODS: Here, we employed molecular dynamics simulations on full length human Smyd3, performed to a total of 1.2 µ-second, in the presence (holo) and absence (apo) of the S-Adenosyl methionine (AdoMet) cofactor. The dynamical features of Smyd3 in apo and holo states have been examined and compared via examining geometrical and electrostatic properties. RESULTS: The results show a distinct dynamics of the C-terminal domain (CTD) in the two states. In the apo state, the CTD undergoes a large hinge like motion and samples more opened configurations, thus acting like a loosened clamp and resulting in expanded substrate binding crevice. In the holo state, the CTD exhibits a restricted motion while the overall structure remains compact, mimicking a closed clamp. This leads to a localized increase in the negative potential at the substrate binding cleft. Further, solvent accessibility of critical residues at the target lysine access channel, important for methylation activity, is increased. CONCLUSIONS: We postulate that AdoMet cofactor acts like a key and locks Smyd3 in a closed conformation. In effect, the cofactor binding restricts the elasticity of the CTD, presenting a compact substrate binding cleft with high negative potential, which may have implications on substrate recruitment via long range electrostatics. GENERAL SIGNIFICANCE: The deletion of the CTD from Smyd3 has been shown to abolish the basal histone methylation activity. Our study highlights the importance of the CTD elasticity in shaping the substrate binding site for recognition and supports the previously proposed role of the CTD in stabilizing the active site for methylation activity.


Assuntos
Coenzimas/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Simulação de Dinâmica Molecular , S-Adenosilmetionina/metabolismo , Sítios de Ligação , Domínio Catalítico , Coenzimas/química , Ativação Enzimática , Histona-Lisina N-Metiltransferase/química , Humanos , Cinética , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , S-Adenosilmetionina/química , Relação Estrutura-Atividade , Especificidade por Substrato
2.
Int J Mol Sci ; 17(7)2016 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-27409613

RESUMO

Non-melanoma skin cancer is the most common skin cancer with an incidence that varies widely worldwide. Among them, actinic keratosis (AK), considered by some authors as in situ squamous cell carcinoma (SCC), are the most common and reflect an abnormal multistep skin cell development due to the chronic ultraviolet (UV) light exposure. No ideal treatment exists, but the potential risk of their development in a more invasive form requires prompt treatment. As patients usually present with multiple AK on fields of actinic damage, there is a need for effective, safe, simple and short treatments which allow the treatment of large areas. To achieve this, daylight photodynamic therapy (DL-PDT) is an innovative treatment for multiple mild actinic keratosis, well tolerated by patients. Patients allocated to the PDT unit, affected by multiple mild-moderate and severe actinic keratosis on sun-exposed areas treated with DL-PDT, were clinically evaluated at baseline and every three months with an Antera 3D, Miravex(©) camera. Clinical and 3D images were performed at each clinical check almost every three months. In this retrospective study, 331 patients (56.7% male, 43.3% female) were treated with DL-PDT. We observed a full clearance in more than two-thirds of patients with one or two treatments. Different responses depend on the number of lesions and on their severity; for patients with 1-3 lesions and with grade I or II AK, a full clearance was reached in 85% of cases with a maximum of two treatments. DL-PDT in general improved skin tone and erased sun damage. Evaluating each Antera 3D images, hemoglobin concentration and pigmentation, a skin color and tone improvement in 310 patients was observed. DL-PDT appears as a promising, effective, simple, tolerable and practical treatment for actinic damage associated with AK, and even treatment of large areas can be with little or no pain. The 3D imaging allowed for quantifying in real time the aesthetic benefits of DL-PDT's increasing compliance.


Assuntos
Ceratose Actínica/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Idoso , Ácido Aminolevulínico/química , Ácido Aminolevulínico/uso terapêutico , Feminino , Humanos , Imageamento Tridimensional , Ceratose Actínica/patologia , Luz , Masculino , Fotoquimioterapia , Estudos Retrospectivos , Índice de Gravidade de Doença
5.
Eur J Dermatol ; 21(4): 546-51, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21659071

RESUMO

The standard methods used to diagnose scalp psoriasis vary in sensitivity, reproducibility, and invasiveness. Videodermoscopy can be used to explore microcirculatory modifications in skin diseases. Psoriasis presents three pathognomonic vascular patterns: red dots, hairpin vessels and red globular rings. Our aim was to create a videodermoscopy scalp psoriasis severity index (VSCAPSI) for evaluation of scalp psoriasis, especially mild and moderate forms that often are not clinically appreciable. VSCAPSI takes into account the area of the scalp affected by psoriasis, the presence and morphology of vascular patterns, the erythema and desquamation. Videodermoscopy images obtained between November 2009 to June 2010 from 900 participants with various scalp and hair disorders were reviewed for distinguishing features. During the 2010 Italian congress on psoriasis, in order to assess the reproducibility and efficacy of the VSCAPSI, 146 dermatologists were asked to evaluate 16 videodermoscopy images of scalp psoriasis using the VSCAPSI. Of the 900 patients, 85 new cases of scalp psoriasis were diagnosed. The other 815 patients were found to be suffering from different scalp and hair diseases. Of 146 dermatologists, 28 did not recognize erythema, 15 desquamation and 7 the vascular patterns. The VSCAPSI provides important evidence for early diagnosis, differential diagnosis, for follow-up and screening.


Assuntos
Dermoscopia/métodos , Psoríase/diagnóstico , Dermatoses do Couro Cabeludo/diagnóstico , Gravação em Vídeo , Diagnóstico Diferencial , Humanos , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Estatísticas não Paramétricas
6.
G Ital Dermatol Venereol ; 153(2): 155-160, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29144098

RESUMO

BACKGROUND: Psoriasis is a common, inflammatory, chronic, relapsing skin disease. The pathogenesis is multifactorial and it is involved both innate and acquired immunity. Several studies have shown the important role of vitamin D in the pathogenesis of this disorder. In this study we have evaluated a possible correlation between vitamin D and clinical severity of psoriasis calculated using the Psoriasis Area Severity Score (PASI) score. METHODS: In this case control study we included 141 Caucasian subjects affected by moderate to severe psoriasis and 62 healthy controls. We have calculated PASI score and serum levels of vitamin D. RESULTS: Psoriatic patients had significantly lower serum levels of 25(OH)D than healthy controls. Using no parametric Spearman's coefficient test between serum levels of vitamin D and the PASI score we found a statistical significant correlation. However, the statistical significance was not reached analyzing separately the patients with psoriatic arthritis, while it was confirmed for patients without an articular involvement. CONCLUSIONS: The present study confirm that serum levels of vitamin D are significantly lower in psoriatic patients and correlate with the clinical severity of psoriasis; these data suggest that psoriatic patients could be screened for vitamin D insufficiency for a more comprehensive management.


Assuntos
Artrite Psoriásica/patologia , Psoríase/patologia , Vitamina D/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Artrite Psoriásica/sangue , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psoríase/sangue , Índice de Gravidade de Doença , Adulto Jovem
8.
Oncotarget ; 7(45): 74097-74106, 2016 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-27765917

RESUMO

Male breast cancer (MBC) is a rare disease. Due to its rarity, MBC research and clinical approach are mostly based upon data derived from its largely known female counterpart. We aimed at investigating whether MBC cases harbor somatic alterations of genes known as prognostic biomarkers and molecular therapeutic targets in female breast cancer.We examined 103 MBC cases, all characterized for germ-line BRCA1/2 mutations, for somatic alterations in PIK3CA, EGFR, ESR1 and CCND1 genes.Pathogenic mutations of PIK3CA were detected in 2% of MBCs. No pathogenic mutations were identified in ESR1 and EGFR. Gene copy number variations (CNVs) analysis showed amplification of PIK3CA in 8.1%, EGFR in 6.8% and CCND1 in 16% of MBCs, whereas deletion of ESR1 was detected in 15% of MBCs. Somatic mutations and gene amplification were found only in BRCA1/2 mutation negative MBCs.Significant associations emerged between EGFR amplification and large tumor size (T4), ER-negative and HER2-positive status, between CCND1 amplification and HER2-positive and MIB1-positive status, and between ESR1 deletion and ER-negative status.Our results show that amplification of targetable oncogenes is frequent in BRCA1/2 mutation negative MBCs and may identify MBC subsets characterized by aggressive phenotype that may benefit from potential targeted therapeutic approaches.


Assuntos
Neoplasias da Mama Masculina/genética , Genes BRCA1 , Genes BRCA2 , Mutação em Linhagem Germinativa , Sequência de Bases , Neoplasias da Mama Masculina/patologia , Classe I de Fosfatidilinositol 3-Quinases/genética , Variações do Número de Cópias de DNA , Predisposição Genética para Doença , Humanos , Masculino , Oncogenes
9.
Eur J Cancer ; 51(16): 2289-95, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26248686

RESUMO

Increasing evidence indicates that common genetic variants may contribute to the heritable risk of breast cancer (BC). In this study, we investigated whether single nucleotide polymorphisms (SNPs), within the 8q24.21 multi-cancer susceptibility region and within BC-associated loci widespread in the genome, may influence the risk of BC in men, and whether they may be associated with specific clinical-pathologic characteristics of male BC (MBC). In the frame of the ongoing Italian Multicenter Study on MBC, we performed a case-control study on 386 MBC cases, including 50 BRCA1/2 mutation carriers, and 1105 healthy male controls, including 197 unaffected BRCA1/2 mutation carriers. All 1491 subjects were genotyped by Sequenom iPLEX technology for a total of 29 susceptibility SNPs. By logistic regression models, we found a significant association with MBC risk for five SNPs: rs1562430 (p=0.002) and rs445114 (p=0.026) both within the 8q24.21 region; rs1011970/9p21.3 (p=0.011), rs614367/11q13.3 (p=0.016) and rs1314913/14q24.1 (p<0.0001). Differences in the distribution of rs614367/11q13.3 genotypes according to oestrogen receptor (ER) status (p=0.006), and of rs1011970/9p21.3 genotypes according to human epidermal growth factor receptor 2 (HER2) status (p=0.002) emerged. Association of rs1011970/9p21.3 risk genotype with HER2+MBC was confirmed by a multivariate analysis. rs1314913/14q24.1 was associated with increased MBC risk in analyses restricted to male BRCA1/2 mutation carriers (p=0.041). In conclusion, we provided the first evidence that the 8q24.21 region is associated with MBC risk. Furthermore, we showed that the SNPs rs1562430/8q24.21 and rs1314913/14q24.1 strongly influence BC risk in men and suggested that the SNP rs1314913/14q24.1 may act as a risk modifier locus in male BRCA1/2 mutation carriers.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama Masculina/genética , Cromossomos Humanos Par 11 , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 8 , Cromossomos Humanos Par 9 , Polimorfismo de Nucleotídeo Único , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama Masculina/patologia , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Frequência do Gene , Predisposição Genética para Doença , Heterozigoto , Homozigoto , Humanos , Itália , Modelos Lineares , Modelos Logísticos , Masculino , Análise Multivariada , Mutação , Razão de Chances , Fenótipo , Valor Preditivo dos Testes , Fatores de Risco
10.
J Dermatol ; 41(9): 783-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24990650

RESUMO

Psoriasis is a chronic inflammatory disease associated with several comorbidities. Osteoporosis is defined as a reduction in bone mineral density with impaired bone microarchitecture. Several mechanisms may be implicated as a possible cause for the association between psoriasis and osteoporosis, such as systemic inflammation, anti-psoriatic drug intake and joint dysfunction for psoriatic arthritis (PsA). The aim of the present study was to assess bone mineral density (BMD) in patients with psoriasis, correlating the prevalence of osteopenia/osteoporosis with Psoriasis Area and Severity Index (PASI) score, mean duration of psoriatic disease, PsA and previous treatments for psoriasis. Forty-three consecutive patients with psoriasis, 19 of whom were affected by the arthropathic form, were enrolled. We evaluated the severity of psoriasis as measured by PASI score, the CASPAR criteria and ultrasounds of the joints to verify the diagnosis of PsA and the age of psoriasis onset to estimate mean disease duration. Patients underwent a bone density scan of the lumbar spine and femoral neck by dual-energy X-ray absorptiometry to measure BMD. Patients with osteopenia/osteoporosis showed a statistically significant longer average duration of psoriatic disease (17 years), compared to patients affected by psoriasis with normal T-score (8.8 years) (P = 0.04). The linear logistic regression confirms a significant relation between mean psoriatic disease duration and BMD alterations (P = 0.04). Our results suggest the necessity of an early diagnostic evaluation of bone metabolism in patients with psoriasis, especially if characterized by longer disease duration.


Assuntos
Artrite Psoriásica/complicações , Osteoporose/etiologia , Adulto , Artrite Psoriásica/epidemiologia , Densidade Óssea , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Osteoporose/epidemiologia , Prevalência
11.
DNA Cell Biol ; 33(2): 102-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24320988

RESUMO

Psoriasis is caused by a combination of genetic, immunologic, and environmental factors. The vitamin D receptor (VDR) is involved in antiproliferative and prodifferentiation pathways in keratinocytes and exerts immunosuppressive effects. We aimed to investigate possible associations between VDR polymorphisms and psoriasis susceptibility and to evaluate functional effects of potential psoriasis-associated polymorphisms. We genotyped 108 patients with psoriasis and 268 healthy controls at 5 VDR polymorphisms (A-1012G, FokI, BsmI, ApaI, and TaqI) by TaqMan allelic-discrimination real-time polymerase chain reaction. We found a significant increased overall risk of psoriasis for the VDR A-1012G promoter polymorphism (odds ratio [OR]=2.43, 95% confidence interval [CI]: 1.15-5.13; p=0.05). A significant higher frequency (p=0.035) of the A allele was found in psoriatic cases compared with controls. In a case-case analysis, a statistically significant association between A-1012G and family history emerged (p=0.033). Furthermore, a significant association of A-1012G risk genotypes with a lower expression of VDR mRNA emerged (p=0.0028). Our data show that VDR promoter A-1012G polymorphism is associated with psoriasis risk and suggest that this polymorphism may modulate psoriasis risk by affecting VDR expression.


Assuntos
Regulação da Expressão Gênica/genética , Predisposição Genética para Doença/genética , Psoríase/genética , Receptores de Calcitriol/genética , Receptores de Calcitriol/metabolismo , Análise de Variância , Estudos de Casos e Controles , Genótipo , Humanos , Itália , Razão de Chances , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genética , Reação em Cadeia da Polimerase em Tempo Real
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