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1.
Nature ; 464(7291): 1043-7, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20393562

RESUMO

Hereditary hypotrichosis simplex is a rare autosomal dominant form of hair loss characterized by hair follicle miniaturization. Using genetic linkage analysis, we mapped a new locus for the disease to chromosome 18p11.22, and identified a mutation (Leu9Arg) in the adenomatosis polyposis down-regulated 1 (APCDD1) gene in three families. We show that APCDD1 is a membrane-bound glycoprotein that is abundantly expressed in human hair follicles, and can interact in vitro with WNT3A and LRP5-two essential components of Wnt signalling. Functional studies show that APCDD1 inhibits Wnt signalling in a cell-autonomous manner and functions upstream of beta-catenin. Moreover, APCDD1 represses activation of Wnt reporters and target genes, and inhibits the biological effects of Wnt signalling during both the generation of neurons from progenitors in the developing chick nervous system, and axis specification in Xenopus laevis embryos. The mutation Leu9Arg is located in the signal peptide of APCDD1, and perturbs its translational processing from the endoplasmic reticulum to the plasma membrane. APCDD1(L9R) probably functions in a dominant-negative manner to inhibit the stability and membrane localization of the wild-type protein. These findings describe a novel inhibitor of the Wnt signalling pathway with an essential role in human hair growth. As APCDD1 is expressed in a broad repertoire of cell types, our findings indicate that APCDD1 may regulate a diversity of biological processes controlled by Wnt signalling.


Assuntos
Hipotricose/genética , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Mutação Puntual/genética , Proteínas Wnt/antagonistas & inibidores , Animais , Diferenciação Celular , Linhagem Celular , Proliferação de Células , Embrião de Galinha , Mapeamento Cromossômico , Cromossomos Humanos Par 18/genética , Genes Dominantes/genética , Genes Reporter/genética , Cabelo/crescimento & desenvolvimento , Cabelo/metabolismo , Folículo Piloso/crescimento & desenvolvimento , Folículo Piloso/metabolismo , Folículo Piloso/patologia , Humanos , Hipotricose/metabolismo , Hipotricose/patologia , Peptídeos e Proteínas de Sinalização Intracelular , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/deficiência , Proteínas de Membrana , Camundongos , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Couro Cabeludo , Transdução de Sinais , Pele , Medula Espinal/citologia , Células-Tronco/citologia , Células-Tronco/metabolismo , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Proteínas de Xenopus/deficiência , Proteínas de Xenopus/genética , Proteínas de Xenopus/metabolismo , Xenopus laevis/embriologia , Xenopus laevis/genética , Xenopus laevis/metabolismo , beta Catenina/metabolismo
2.
Endocrine ; 84(1): 193-202, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38123877

RESUMO

PURPOSE: The utility of repeating ultrasound-guided fine-needle aspiration (US-FNAB) in the follow-up of benign (THY2) thyroid nodules is still debated. The aim of this study was to retrospectively investigate the diagnostic value of re-biopsy of thyroid nodules following an initially benign result. METHODS: We retrospectively analyzed US-FNABs performed at the Unit of Endocrinology of Modena from 2006 to 2009. The firstly benign cytological result was compared with the cytological results of subsequent US-FNABs (2nd and/or 3rd) executed on the same nodule. RESULTS: Among 10449 US-FNABs, 6270 (60%) received a THY2 cytological categorization. Of them, 278 (4.43%) underwent a subsequent US-FNAB: 86.7% maintained the same cytology, 32 (11.5%) changed to THY3 (indeterminate) and 5 (1.8%) to THY4 (suspicious of malignancy). Among the 24 nodules addressed to surgery, 9 (37%) were histologically malignant, with an overall miss rate of 3.2%. Male patients had higher risk of discordant results at subsequent US-FNAB (p = 0.005, OR:3.59, 95%CI:1.453-7.769) while dimensional increase above 5 mm was predictive of concordant benign cytology (p = 0.036, OR:0.249, 95%CI:0.068-0.915). Age, suspicious US characteristics, and distance between US-FNABs resulted not predictive. CONCLUSIONS: Re-biopsy of benign nodules confirmed the benign nature in most cases. In case of discordant cytology, relocation in indeterminate category was the most common. The histological diagnosis of cancer occurred in one quarter of nodules surgically removed, with a low overall clinically significant miss rate. Thus, a small percentage of false negatives exists; males and subjects with US suspicious nodules should be carefully followed-up, considering case by case re-biopsy possibility.


Assuntos
Neoplasias da Glândula Tireoide , Nódulo da Glândula Tireoide , Humanos , Masculino , Nódulo da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/cirurgia , Biópsia por Agulha Fina , Estudos Retrospectivos , Seguimentos
3.
Artigo em Inglês | MEDLINE | ID: mdl-20798775

RESUMO

Cerebral cavernous malformations (CCMs) represent a common autosomal dominant disorder that predisposes patients to haemorrhagic strokes and focal neurological signs. About 56% of the hereditary forms of CCMs have been so far associated with mutations in the KRIT1 (Krev Interaction Trapped 1) gene, located at 7q21.2 (CCM1 locus). We described the complete loss of 7q21.2 locus encompassing the KRIT1 gene and 4 flanking genes in a CCM family by using a dense set of 12 microsatellite markers. The complete loss of the maternal copy of KRIT1 gene region was confirmed by Real-Time Quantitative Polymerase Chain Reaction (RT-QPCR) and the same approach was used for expression analysis. Additional RT-QPCR analysis showed the extension of the deletion, for a total of 700 kb, to the adjacent downstream and upstream-located genes, MTERF, AKAP9, CYP51A1, as well as a partial loss of the ANKIB1 gene. Here we report the molecular characterization of an interstitial small genomic deletion of the 7q21.2 region in a CCMs affected family, encompassing the KRIT1 gene. Our findings confirm the loss of function mechanism for the already known CCM1 locus, without any evident involvement of the other deleted genes. Moreover, our investigations highlight the usefulness of the RT-QPCR to the molecular characterization of the breakpoints genomic deletions and to the identification of internal deleted genes involved in the human genetic diseases.


Assuntos
Cromossomos Humanos Par 7/genética , Hemangioma Cavernoso/genética , Malformações Arteriovenosas Intracranianas/genética , Proteínas Associadas aos Microtúbulos/genética , Polimorfismo Genético/genética , Proteínas Proto-Oncogênicas/genética , Deleção de Sequência , Adulto , Neoplasias Encefálicas/genética , Criança , Feminino , Humanos , Proteína KRIT1 , Masculino , Proteínas Associadas aos Microtúbulos/deficiência , Pessoa de Meia-Idade , Linhagem , Proteínas Proto-Oncogênicas/deficiência , Reação em Cadeia da Polimerase Via Transcriptase Reversa
4.
Acta Biomed ; 81 Suppl 1: 31-6, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20518189

RESUMO

Subclinical thyroid disease (STD) is defined as circulating concentrations of free T4 and free T3 within their respective reference ranges in the presence of abnormal circulating concentrations of TSH. SCD is being diagnosed more frequently in clinical practice and is reported to be more prevalent in elderly as compared to young or adult subjects. The clinical impact of subclinical thyroid dysfunction is still a matter of debate, although it has been associated with various negative clinical outcomes, such as increased cardiovascular risk, reduction in bone density, decline in cognitive function, and increased risk of overt thyroid dysfunction. The treatment of STD is controversial and there is no consensus on the TSH cutoff values which can be used as indicators for treatment, especially in elderly subjects. In the present review, we report data on the prevalence of STD and on the potential clinical consequences of these disorders. Also, data of the Literature regarding the issue of the treatment of STD in relation to the age of the patient are reported.


Assuntos
Hipertireoidismo/complicações , Hipotireoidismo/complicações , Idoso , Remodelação Óssea , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/etiologia , Transtornos Cognitivos/etiologia , Terapia de Reposição Hormonal , Humanos , Hipertireoidismo/sangue , Hipotireoidismo/sangue , Hormônios Tireóideos/sangue
5.
Andrology ; 8(6): 1720-1727, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32593193

RESUMO

BACKGROUND: It has recently been suggested that the hypergonadotropic hypogonadism characterizing Klinefelter syndrome (KS) might not be due to a steroidogenic dysfunction per se, but mainly to an altered testosterone (T) secretion into the bloodstream. However, the Leydig cell functionality remains incompletely studied in KS, and new markers should be considered. Previous data indicated that chronic hCG stimulation influences the production of both insulin-like peptide 3 (INSL3) and 25-hydroxy-vitamin D (25-VD) in eugonadal men. AIM OF THE STUDY: To evaluate INSL3 and 25-VD serum levels, as markers of Leydig cell functionality, in association with sex steroids, after an acute hCG test in a group of KS patients and healthy volunteers. METHODS: A retrospective analysis of a prospective case-control clinical trial was carried out. KS patients (n = 11) and age-matched healthy controls (n = 11) provided a basal blood sample (V0) immediately followed by a single intramuscular injection of hCG 5000 IU. Blood samples were taken in the following five days (V1-V5). RESULTS: At baseline, INSL3 was lower in KS patients compared with controls (P = .007). When adjusted for INSL3 levels, the production of steroids was similar between KS patients and controls. 25-VD was in the insufficient range both in KS patients and in controls and was not different (P = .064). Acute hCG stimulation increased neither INSL3 nor 25-VD in both KS patients and controls. In controls, an inverse correlation was detected between INSL3 levels and body mass index (P = .020) and waist circumference (P = .020). CONCLUSIONS: INSL3 secretion is independent from steroidogenesis, and its production is mostly not influenced by acute hCG stimulation both in KS men and in controls. INSL3 serum levels should be considered as a marker of Leydig cell differentiation and numbers rather than steroidogenesis. 25-VD serum levels are also not increased by a single acute hCG administration, which was not able to restore the normal concentrations of 25-VD.


Assuntos
Calcifediol/sangue , Gonadotropina Coriônica/metabolismo , Insulina/sangue , Síndrome de Klinefelter/sangue , Células Intersticiais do Testículo/metabolismo , Gonadotropina Coriônica/sangue , Humanos , Células Intersticiais do Testículo/citologia , Masculino , Proteínas , Estudos Retrospectivos , Testosterona/sangue
6.
Hum Mutat ; 24(5): 441, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15459969

RESUMO

The nevoid basal cell carcinoma syndrome (NBCCS) is an autosomal dominant genetic disease characterized by numerous basal cell carcinomas, odontogenic keratocysts of the jaws, palmar and plantal pits, skeletal abnormalities, and calcification of the falx cerebri. The gene responsible for this syndrome is the PTCH tumor suppressor gene encoding for the sonic hedgehog receptor. In this paper, we report thirteen novel mutations identified in the first screening of NBCCS patients in Italy. Except for p.T230P and p.F505_L506delinsLR, all the other mutations are predicted to determine a premature truncation of the protein.


Assuntos
Alelos , Síndrome do Nevo Basocelular/genética , Mutação/genética , Receptores de Superfície Celular/genética , Sequência de Aminoácidos , Sequência de Bases , Códon sem Sentido/genética , Análise Mutacional de DNA , Éxons/genética , Feminino , Duplicação Gênica , Testes Genéticos , Humanos , Itália , Masculino , Dados de Sequência Molecular , Mutação de Sentido Incorreto/genética , Receptores Patched , Receptor Patched-1 , Linhagem , Sítios de Splice de RNA/genética , Receptores de Superfície Celular/química , Deleção de Sequência/genética
8.
Eur J Hum Genet ; 19(1): 102-7, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20736978

RESUMO

Genome-wide high-resolution array analysis is rapidly becoming a reliable method of diagnostic investigation in individuals with mental retardation and congenital anomalies, leading to the identification of several novel microdeletion and microduplication syndromes. We have identified seven individuals with duplication on chromosome 14q11.2q13.1, who exhibited idiopathic developmental delay and cognitive impairment, severe speech delay, and developmental epilepsy. Among these cases, the minimal common duplicated region on chromosome 14q11.2q13.1 includes only three genes, FOXG1, C14orf23, and PRKD1. We propose that increased dosage of Forkhead Box G1 (FOXG1) is the best candidate to explain the abnormal neurodevelopmental phenotypes observed in our patients. Deletions and inactivating mutations of FOXG1 have been associated with a Rett-like syndrome characterized by hypotonia, irritability, developmental delay, hand stereotypies, and deceleration of head growth. FOXG1, encoding a brain-specific transcription factor, has an important role in the developing brain. In fact, in vivo studies in chicken brain demonstrated that overexpression of FOXG1 results in thickening of the neuroepithelium and outgrowth of the telencephalon and mesencephalum, secondary to a reduction in neuroepithelial cell apoptosis.


Assuntos
Cromossomos Humanos Par 14/genética , Deficiências do Desenvolvimento/genética , Epilepsia/genética , Fatores de Transcrição Forkhead/genética , Duplicação Gênica , Deficiência Intelectual/genética , Transtornos do Desenvolvimento da Linguagem/genética , Proteínas do Tecido Nervoso/genética , Adulto , Pré-Escolar , Hibridização Genômica Comparativa , Feminino , Humanos , Lactente , Masculino , Análise de Sequência com Séries de Oligonucleotídeos
9.
Eur J Hum Genet ; 18(7): 768-75, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20125191

RESUMO

Rubinstein-Taybi syndrome (RSTS) is a rare autosomal dominant disorder characterised by facial dysmorphisms, growth and psychomotor development delay, and skeletal defects. The known genetic causes are point mutations or deletions of the CREBBP (50-60%) and EP300 (5%) genes. To detect chromosomal rearrangements indicating novel positional candidate RSTS genes, we used a-CGH to study 26 patients fulfilling the diagnostic criteria for RSTS who were negative at fluorescence in situ hybridisation analyses of the CREBBP and EP300 regions, and direct sequencing analyses of the CREBBP gene. We found seven imbalances (27%): four de novo and three inherited rearrangements not reported among the copy number variants. A de novo 7p21.1 deletion of 500 kb included the TWIST1 gene, a suggested candidate for RSTS that is responsible for the Saethre-Chotzen syndrome, an entity that enters in differential diagnosis with RSTS. A similar issue of differential diagnosis was raised by a large 4.3 Mb 2q22.3q23.1 deletion encompassing ZEB2, the gene responsible for the Mowat-Wilson syndrome, whose signs may overlap with RSTS. Positional candidate genes could not be sought in the remaining pathogenetic imbalances, because of the size of the involved region (a 9 Mb 2q24.3q31.1 deletion) and/or the relative paucity of suitable genes (a 5 Mb 3p13p12.3 duplication). One of the inherited rearrangements, the 17q11.2 379Kb duplication, represents the reciprocal event of the deletion underlying an overgrowth syndrome, both being mediated by the NF1-REP-P1 and REP-P2 sub-duplicons. The contribution of this and the other detected CNVs to the clinical RSTS phenotype is difficult to assess.


Assuntos
Proteína de Ligação a CREB/genética , Dosagem de Genes/genética , Síndrome de Rubinstein-Taybi/genética , Adolescente , Adulto , Desequilíbrio Alélico/genética , Criança , Pré-Escolar , Mapeamento Cromossômico , Hibridização Genômica Comparativa , Análise Mutacional de DNA , Fácies , Feminino , Deformidades Congênitas do Pé/complicações , Deformidades Congênitas do Pé/genética , Genoma Humano/genética , Deformidades Congênitas da Mão/complicações , Deformidades Congênitas da Mão/genética , Humanos , Lactente , Recém-Nascido , Padrões de Herança/genética , Masculino , Síndrome de Rubinstein-Taybi/complicações , Adulto Jovem
10.
Am J Med Genet A ; 121A(3): 214-8, 2003 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-12923860

RESUMO

Congenital malformations (CM) affect 2-3% of all births, the cause of which, when known, is genetic in 80-90% of cases. A genetic consultation (GC) is indicated for the parents of a child affected by a CM. This study analyzes the parental utilization of genetic counseling (GCU) and its possible influencing factors after termination of pregnancy (TOP) because of fetal anomalies or after the birth of a child affected by a major malformation. The study concerns cases in North-East Italy where there is a CM registry and a center-satellite system for genetic counseling. The results of this analysis are also compared to other similar studies, which address the same topic. Between 1981 and 2000, 1,235 out of 14,888 GC were performed because of the presence of a CM in a child/fetus. In the same period, 4,933 births and 1,112 TOPs were registered. The overall GCU was 19%, with significant differences according to malformative phenotype, severity of the malformative condition, type of birth, and viability. Genetic counseling was performed significantly sooner following TOP than after the birth of a malformed child. GCU showed an unequal distribution according to the parents' place of residence, suggesting that easy and equal access to the genetic service was probably not well provided for. Our results suggest that genetic services should be integrated with related services, and that the public and physicians need a greater awareness of these services.


Assuntos
Anormalidades Congênitas , Aconselhamento Genético/estatística & dados numéricos , Pais/psicologia , Pré-Escolar , Anormalidades Congênitas/diagnóstico , Anormalidades Congênitas/epidemiologia , Anormalidades Congênitas/genética , Feminino , Morte Fetal , Humanos , Lactente , Recém-Nascido , Itália/epidemiologia , Países Baixos/epidemiologia , Cooperação do Paciente , Gravidez , Resultado da Gravidez/epidemiologia , Diagnóstico Pré-Natal
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