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1.
BMJ Case Rep ; 17(5)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38697680

RESUMO

Neurofibromatosis type 1 (NF1) is an autosomal dominant disease with complete penetrance, most commonly known to affect the skin and eyes. Although lung involvement in the form of cysts and bullae occurs in up to 20% of adults, the seemingly intuitive association of NF1 and spontaneous pneumothorax is not widely recognised among clinicians. Here, we report the second case of recurring spontaneous pneumothorax in the context of NF1 with a confirmed molecular diagnosis. In both cases, the NF1 variants featured a premature stop codon in the C-terminal protein domain. Interestingly, our patient had mild skin symptoms, suggesting that spontaneous pneumothorax may not be correlated with cutaneous disease severity. More genotype-phenotype correlation studies are needed for NF1 in general and for its link to spontaneous pneumothorax in particular.


Assuntos
Neurofibromatose 1 , Pneumotórax , Recidiva , Humanos , Pneumotórax/genética , Neurofibromatose 1/complicações , Neurofibromatose 1/genética , Masculino , Estudos de Associação Genética , Adulto , Feminino , Neurofibromina 1/genética , Códon sem Sentido
2.
Clin Epigenetics ; 14(1): 185, 2022 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-36572941

RESUMO

BACKGROUND: It has been suggested that antenatal exposure to environmental endocrine disruptors is responsible for adverse trends in male reproductive health, including male infertility, impaired semen quality, cryptorchidism and testicular cancer, a condition known as testicular dysgenesis syndrome. Anogenital distance (AGD) is an anthropomorphic measure of antenatal exposure to endocrine disruptors, with higher exposure levels leading to shortened AGD. We hypothesized that exposure to endocrine disruptors could lead to changes in DNA methylation during early embryonic development, which could then persist in the sperm of infertile men with shortened AGD. RESULTS: Using fluorescence activated cell sorting based on staining with either YO-PRO-1 (YOPRO) or chromomycin-3 (CMA3), we isolated four sperm fractions from eleven infertile men with short AGD and ten healthy semen donors. We examined DNA methylation in these sorted spermatozoa using reduced representation bisulfite sequencing. We found that fractions of spermatozoa from infertile men stained with CMA3 or YOPRO were more likely to contain transposable elements harboring an estrogen receptor response element (ERE). Abnormal sperm (as judged by high CMA3 or YOPRO staining) from infertile men shows substantial hypomethylation in estrogenic Alu sequences. Conversely, normal sperm fractions (as judged by low CMA3 or YO-PRO-1 staining) of either healthy donors or infertile patients were more likely to contain hypermethylated Alu sequences with ERE. CONCLUSIONS: Shortened AGD, as related to previous exposure to endocrine disruptors, and male infertility are accompanied by increased presence of hormonal response elements in the differentially methylated regulatory sequences of the genome of sperm fractions characterized by chromatin decondensation and apoptosis.


Assuntos
Disruptores Endócrinos , Infertilidade Masculina , Neoplasias Testiculares , Humanos , Masculino , Feminino , Gravidez , Análise do Sêmen , Neoplasias Testiculares/genética , Metilação de DNA , Disruptores Endócrinos/metabolismo , Sêmen , Espermatozoides/metabolismo , Infertilidade Masculina/induzido quimicamente , Infertilidade Masculina/genética , Estrogênios/metabolismo , Sequências Repetitivas de Ácido Nucleico
4.
Science ; 377(6610): eabq4515, 2022 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-36048943

RESUMO

At the present time, no viable treatment exists for cognitive and olfactory deficits in Down syndrome (DS). We show in a DS model (Ts65Dn mice) that these progressive nonreproductive neurological symptoms closely parallel a postpubertal decrease in hypothalamic as well as extrahypothalamic expression of a master molecule that controls reproduction-gonadotropin-releasing hormone (GnRH)-and appear related to an imbalance in a microRNA-gene network known to regulate GnRH neuron maturation together with altered hippocampal synaptic transmission. Epigenetic, cellular, chemogenetic, and pharmacological interventions that restore physiological GnRH levels abolish olfactory and cognitive defects in Ts65Dn mice, whereas pulsatile GnRH therapy improves cognition and brain connectivity in adult DS patients. GnRH thus plays a crucial role in olfaction and cognition, and pulsatile GnRH therapy holds promise to improve cognitive deficits in DS.


Assuntos
Cognição , Disfunção Cognitiva , Síndrome de Down , Hormônio Liberador de Gonadotropina , Transtornos do Olfato , Adulto , Animais , Cognição/efeitos dos fármacos , Cognição/fisiologia , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Modelos Animais de Doenças , Síndrome de Down/complicações , Síndrome de Down/tratamento farmacológico , Síndrome de Down/psicologia , Feminino , Hormônio Liberador de Gonadotropina/farmacologia , Hormônio Liberador de Gonadotropina/fisiologia , Hormônio Liberador de Gonadotropina/uso terapêutico , Humanos , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Transtornos do Olfato/tratamento farmacológico , Transtornos do Olfato/etiologia , Transmissão Sináptica/efeitos dos fármacos , Adulto Jovem
5.
Swiss Med Wkly ; 151: w20406, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33578430

RESUMO

AIMS OF THE STUDY: The European Society of Medical Oncology (ESMO) recommends that countries should have reference centres to provide adequate diagnosis and treatment of gestational trophoblastic disease. A trophoblastic disease centre in the French-speaking part of Switzerland was inaugurated in 2009. The objectives of this study were to report the activity of the centre during the last 10 years and analyse gestational trophoblastic disease outcomes. METHODS: This was a retrospective study with data collected from all cases of gestational trophoblastic disease referred to the centre from 2009 to 2018. All histological specimens as well as data for treatment and follow-up of gestational trophoblastic disease and neoplasia were reviewed. Clinical features, including age, prognostic score and International Federation of Gynecology and Obstetrics (FIGO) stages (in the case of gestational trophoblastic neoplasia), human chorionic gonadotropin (hCG) follow-up, treatment and outcome were reported. RESULTS: The centre registered 354 patients, and these patients presented 156 cases of partial hydatidiform moles, 163 cases of complete hydatidiform moles and 14 cases of gestational trophoblastic neoplasia. During follow-up, 35 gestational trophoblastic neoplasms were diagnosed after hCG persistence. After pathology review, the overall agreement rates between our centre and a participating provider hospital was 82%. Methotrexate was the first line of single-agent chemotherapy for most patients, with resistance rates of 23%. Multi-agent chemotherapy was used as first-line treatment for five patients. None of the patients followed up by the centre died from gestational trophoblastic disease. CONCLUSIONS: This study reflects the activity of the Swiss trophoblastic disease centre from the French-speaking part of Switzerland created in 2009, and its role as local and national reference centre, in terms of global health, for women with gestational trophoblastic disease.


Assuntos
Doença Trofoblástica Gestacional , Mola Hidatiforme , Gonadotropina Coriônica , Feminino , Doença Trofoblástica Gestacional/diagnóstico , Doença Trofoblástica Gestacional/tratamento farmacológico , Doença Trofoblástica Gestacional/epidemiologia , Humanos , Gravidez , Estudos Retrospectivos , Suíça/epidemiologia
6.
BMC Nephrol ; 21(1): 107, 2020 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-32220227

RESUMO

BACKGROUND: The conjunction of hepatitis and renal disease can be seen in several clinical context, including karyomegalic nephritis (KIN). Karyomegalic nephritis (KIN) is a rare genetic disease, with less than 50 cases reported, which incidence is probably underestimated. We report here an unusual case presentation of KIN with obtention of several organ biopsies and a novel mutation leading to the disease. CASE PRESENTATION: A 58 year old Caucasian without relevant family history presents with advanced chronic kidney disease, elevated liver enzymes and recurrent pulmonary infection. Familial history was negative. Renal biopsy revealed a chronic tubulo-intertsitial nephritis with enlarged and irregular hyperchromatic nuclei. Karyomegalic nephritis (KIN) was confirmed by genetic testing with a non-sense mutation and a deletion in the Fanconi anemia associated nuclease 1 (FAN1) gene. CONCLUSIONS: KIN is rare disease to be suspected in the presence of renal disease, biological hepatitis and recurrent pulmonary infections, even without a familial history. Diagnosis of this condition is crucial to perform family screening, avoid progression factors, and adapt post transplantation immunosuppression. Finally, avoiding familial heterozygote donors appears of major importance in this condition.


Assuntos
Endodesoxirribonucleases/genética , Exodesoxirribonucleases/genética , Rim , Testes de Função Hepática/métodos , Fígado , Enzimas Multifuncionais/genética , Nefrite Intersticial , Infecções Respiratórias , Códon sem Sentido , Diagnóstico Diferencial , Progressão da Doença , Humanos , Rim/diagnóstico por imagem , Rim/patologia , Testes de Função Renal , Transplante de Rim/métodos , Fígado/diagnóstico por imagem , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Nefrite Intersticial/diagnóstico , Nefrite Intersticial/genética , Nefrite Intersticial/fisiopatologia , Nefrite Intersticial/terapia , Tamanho do Órgão , Diálise Peritoneal/métodos , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/etiologia , Deleção de Sequência
7.
PLoS One ; 14(6): e0208371, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31181066

RESUMO

Di(2-ethylhexyl)phthalate (DEHP) interferes with sex hormones signaling pathways (SHP). C57BL/6J mice prenatally exposed to 300 mg/kg/day DEHP develop a testicular dysgenesis syndrome (TDS) at adulthood, but similarly-exposed FVB/N mice are not affected. Here we aim to understand the reasons behind this drastic difference that should depend on the genome of the strain. In both backgrounds, pregnant female mice received per os either DEHP or corn oil vehicle and the male filiations were examined. Computer-assisted sperm analysis showed a DEHP-induced decreased sperm count and velocities in C57BL/6J. Sperm RNA sequencing experiments resulted in the identification of the 62 most differentially expressed RNAs. These RNAs, mainly regulated by hormones, produced strain-specific transcriptional responses to prenatal exposure to DEHP; a pool of RNAs was increased in FVB, another pool of RNAs was decreased in C57BL/6J. In FVB/N, analysis of non-synonymous single nucleotide polymorphisms (SNP) impacting SHP identified rs387782768 and rs29315913 respectively associated with absence of the Forkhead Box A3 (Foxa3) RNA and increased expression of estrogen receptor 1 variant 4 (NM_001302533) RNA. Analysis of the role of SNPs modifying SHP binding sites in function of strain-specific responses to DEHP revealed a DEHP-resistance allele in FVB/N containing an additional FOXA1-3 binding site at rs30973633 and four DEHP-induced beta-defensins (Defb42, Defb30, Defb47 and Defb48). A DEHP-susceptibility allele in C57BL/6J contained five SNPs (rs28279710, rs32977910, rs46648903, rs46677594 and rs48287999) affecting SHP and six genes (Svs2, Svs3b, Svs4, Svs3a, Svs6 and Svs5) epigenetically silenced by DEHP. Finally, targeted experiments confirmed increased methylation in the Svs3ab promoter with decreased SEMG2 persisting across generations, providing a molecular explanation for the transgenerational sperm velocity decrease found in C57BL/6J after DEHP exposure. We conclude that the existence of SNP-dependent mechanisms in FVB/N inbred mice may confer resistance to transgenerational endocrine disruption.


Assuntos
Dietilexilftalato/farmacologia , Disruptores Endócrinos/farmacologia , Animais , Metilação de DNA , Epigênese Genética/efeitos dos fármacos , Epigênese Genética/genética , Feminino , Masculino , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Oligospermia/induzido quimicamente , Polimorfismo de Nucleotídeo Único , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Proteínas Secretadas pela Vesícula Seminal/genética , Especificidade da Espécie , Espermatozoides/efeitos dos fármacos
8.
PLoS One ; 12(1): e0170441, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28085963

RESUMO

The endocrine disruptor bis(2-ethylhexyl) phthalate (DEHP) has been shown to exert adverse effects on the male animal reproductive system. However, its mode of action is unclear and a systematic analysis of its molecular targets is needed. In the present study, we investigated the effects of prenatal exposure to 300 mg/kg/day DEHP during a critical period for gonads differentiation to testes on male mice offspring reproductive parameters, including the genome-wide RNA expression and associated promoter methylation status in the sperm of the first filial generation. It was observed that adult male offspring displayed symptoms similar to the human testicular dysgenesis syndrome. A combination of sperm transcriptome and methylome data analysis allowed to detect a long-lasting DEHP-induced and robust promoter methylation-associated silencing of almost the entire cluster of the seminal vesicle secretory proteins and antigen genes, which are known to play a fundamental role in sperm physiology. It also resulted in the detection of a DEHP-induced promoter demethylation associated with an up-regulation of three genes apparently not relevant for sperm physiology and partially related to the immune system. As previously reported, DEHP induced an increase in mir-615 microRNA expression and a genome-wide decrease in microRNA promoter methylation. A functional analysis revealed DEHP-induced enrichments in down-regulated gene transcripts coding for peroxisome proliferator-activated receptors and tumor necrosis factor signaling pathways, and in up-regulated gene transcripts coding for calcium binding and numerous myosin proteins. All these enriched pathways and networks have been described to be associated in some way with the reproductive system. This study identifies a large new array of genes dysregulated by DEHP that may play a role in the complex system controlling the development of the male reproductive system.


Assuntos
Dietilexilftalato/toxicidade , Disruptores Endócrinos/toxicidade , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Reprodução/genética , Doenças Testiculares/induzido quimicamente , Animais , Metilação de DNA/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Feminino , Desenvolvimento Fetal/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Masculino , Camundongos , MicroRNAs/metabolismo , Gravidez , Regiões Promotoras Genéticas , Síndrome , Doenças Testiculares/genética , Testículo/efeitos dos fármacos , Testículo/embriologia , Transcriptoma
9.
Reprod Toxicol ; 35: 150-5, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23142538

RESUMO

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is an endocrine disruptor affecting the reproductive system in humans. The aim of this study was to evaluate the effects of TCDD administered to pregnant mice at two different doses (2-10 ng/kg/day), on imprinted genes in the male offspring. The degree of methylation and the mRNA expression of Snrpn, Peg3 and Igf2r were analyzed in the sperm, skeletal muscle and liver. TCDD administration (10 ng/kg/day) decreased the sperm count in the male offspring. It did not affect methylation but increased mRNA expression of Snrpn, Peg3, Igf2r and Air ncRNA. In muscle and liver, TCDD (10 ng/kg/day) induced increases in methylation and decreases in mRNA expression of Igf2r. These results show that the robust effects of TCDD on the mRNA expression of Snrpn, Peg3 and Igf2r genes in the sperm and of Igf2r in the muscle and liver are unrelated to changes in methylation in their respective genes.


Assuntos
Disruptores Endócrinos/toxicidade , Dibenzodioxinas Policloradas/toxicidade , Animais , Metilação de DNA , Feminino , Impressão Genômica , Fatores de Transcrição Kruppel-Like/genética , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Troca Materno-Fetal , Camundongos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Gravidez , RNA Mensageiro/metabolismo , Receptor IGF Tipo 2/genética , Contagem de Espermatozoides , Proteínas Centrais de snRNP/genética
10.
J Child Sex Abus ; 19(3): 337-44, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20509080

RESUMO

We report the case of a 34-year-old female resulting from a father-daughter sexual abuse and presenting a phenotype of mild intellectual disability with minor dysmorphic features. Karyotyping showed a normal 46, XX constitution. Array-based comparative genomic hybridization (array-CGH) revealed a heterozygote 320kb 6p22.3 microdeletion in the proband, encompassing only one known gene, and therefore unlikely to be the cause of the phenotype. However, the role of other genetic factors, such as a recessive condition, could not be ruled out as a putative cause for the phenotype. On the other hand, the role played by a heavily detrimental familial situation on the development and outcome, and possibly leading or contributing to a mild intellectual disability, should be taken into account.


Assuntos
Abuso Sexual na Infância/psicologia , Deleção Cromossômica , Cromossomos Humanos Par 6/genética , Relações Pai-Filho , Endogamia , Incesto/psicologia , Deficiência Intelectual/genética , Deficiência Intelectual/psicologia , Peptídeos e Proteínas de Sinalização Intercelular/genética , Meio Social , Adolescente , Adulto , Anormalidades Craniofaciais/genética , Anormalidades Craniofaciais/psicologia , Violência Doméstica/psicologia , Feminino , Triagem de Portadores Genéticos , Humanos , Linhagem , Fenótipo , Gravidez , Autoimagem
11.
Reproduction ; 139(2): 373-9, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19887539

RESUMO

Endocrine-disrupting chemicals (EDCs), among which is the antiandrogen vinclozolin (VCZ), have been reported to affect the male reproductive system. In this study, VCZ was administered to pregnant mice at the time of embryo sex determination, and its possible effects on the differentially methylated domains (DMDs) of two paternally (H19 and Gtl2) and three maternally (Peg1, Snrpn, and Peg3) imprinted genes were tested in the male offspring. The CpGs methylation status within the five gene DMDs was analyzed in the sperm, tail, liver, and skeletal muscle DNAs by pyrosequencing. In the sperm of controls, the percentages of methylated CpGs were close to the theoretical values of 100 and 0% in paternally or maternally imprinted genes respectively. VCZ decreased the percentages of methylated CpGs of H19 and Gtl2 (respective values 83.1 and 91.5%) and increased those of Peg1, Snrpn, and Peg3 (respective values 11.3, 18.3, and 11.2%). The effects of VCZ were transgenerational, but they disappeared gradually from F1 to F3. The mean sperm concentration of the VCZ-administered female offspring was only 56% of that of the controls in the F1 offspring, and it was back to normal values in the F2 and F3 offspring. In the somatic cells of controls, the percentages of methylated CpGs were close to the theoretical value of 50% and, surprisingly, VCZ altered the methylation of Peg3. We propose that the deleterious effects of VCZ on the male reproductive system are mediated by imprinting defects in the sperm. The reported effects of EDCs on human male spermatogenesis might be mediated by analogous imprinting alterations.


Assuntos
Antagonistas de Androgênios/toxicidade , Metilação de DNA/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Impressão Genômica/efeitos dos fármacos , Oxazóis/toxicidade , Efeitos Tardios da Exposição Pré-Natal , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Animais , Ilhas de CpG/efeitos dos fármacos , Feminino , Genótipo , Fatores de Transcrição Kruppel-Like/genética , Fígado/metabolismo , Masculino , Camundongos , Músculo Esquelético/metabolismo , Fenótipo , Gravidez , Proteínas/genética , RNA Longo não Codificante , Reprodução/efeitos dos fármacos , Reprodução/genética , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatogênese/genética , Espermatozoides/metabolismo , Espermatozoides/patologia , Cauda/metabolismo , Proteínas Centrais de snRNP/genética
12.
Reprod Toxicol ; 28(4): 536-41, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19549566

RESUMO

Some steps of the assisted reproduction techniques, such as superovulation, may interfere with imprinting reprogramming. In the present study, superovulation was induced in the mouse and its possible effects on the differentially methylated domains of 2 paternally (H19 and Gtl2) and 3 maternally (Peg1, Snrpn and Peg3) imprinted genes were tested in the male offspring over 2 generations. The CpGs methylation status was analyzed by pyro- and bisulfite sequencing. In liver, skeletal muscle and tail, no effect of superovulation could be observed. In the sperm, however, a significant 6% decrease in the number of methylated CpGs of H19 and significant 2.8- and 7.0-fold increases in those of Peg1 and Snrpn, respectively were observed following superovulation. The changes were still present in the H19 and Snrpn genes of the second generation offspring. This suggests that superovulation in the mother transgenerationally affects the offspring sperm methylation pattern.


Assuntos
Metilação de DNA , Impressão Genômica , Espermatozoides/metabolismo , Superovulação/genética , Animais , Ilhas de CpG , Masculino , Camundongos , Camundongos Endogâmicos , Proteínas Centrais de snRNP
13.
Eur J Med Genet ; 51(5): 472-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18539553

RESUMO

We report here a three generations family with nevoid basal cell carcinoma syndrome (NBCCS) in which the diagnosis was made only after a second trimester of pregnancy ultrasonography revealing fetal cranio-cerebral malformations. A mutation was subsequently characterized in the aborted fetus, as well as in the mother, sister and grand-mother as an 18bp deletion in exon 15 of the patched homologue 1 (PTCH1) gene. MC1R gene sequencing identified in two NBCCS patients affected by multiple basal cell carcinomas a functional MC1R variant, D294H, previously shown to be associated with skin cancer risk. This variant was absent in the NBCCS patient that did not develop basal cell carcinomas, suggesting that this variant could have favored the development of skin cancers, in patients carrying the PTCH1 mutation.


Assuntos
Síndrome do Nevo Basocelular/genética , Síndrome do Nevo Basocelular/diagnóstico , Corpo Caloso/patologia , Anormalidades Craniofaciais/diagnóstico , Anormalidades Craniofaciais/genética , Éxons , Saúde da Família , Feminino , Deleção de Genes , Humanos , Mutação , Receptores Patched , Receptor Patched-1 , Linhagem , Gravidez , Diagnóstico Pré-Natal , Receptor Tipo 1 de Melanocortina/genética , Receptores de Superfície Celular/genética
14.
Pediatr Res ; 61(5 Pt 2): 51R-57R, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17413849

RESUMO

Imprinted genes comprise a small subset of the genome whose epigenetic reprogramming in the germ line is necessary for subsequent normal embryonic development. This reprogramming and resetting of the imprints, through an erasure/acquisition/maintenance cycle, is a subtle and tightly orchestrated phenomenon, involving specific genomic regions and methylation enzymes. Dysregulation of imprinted genes has indeed been shown to lead to several human disorders as well as to affect placental and fetal growth. There have been numerous and conflicting studies assessing the possible association of imprinting disorders with assisted reproductive techniques. This work analyzes all relevant and available reports with regard to the association between assisted reproductive techniques and imprinting disorders. It also discusses whether this possibly increased risk of imprinting disorders may be linked to specific steps of these reproductive techniques or already present in the gametes of infertile patients. A better understanding of epigenetic reprogramming in the germ line is absolutely necessary both to assess the safety of these methods and of the use of impaired spermatogenesis gametes for assisted reproduction.


Assuntos
Epigênese Genética , Impressão Genômica , Medicina Reprodutiva , Síndrome de Angelman/genética , Síndrome de Beckwith-Wiedemann/genética , Metilação de DNA , Feminino , Retardo do Crescimento Fetal , Feto/anatomia & histologia , Feto/fisiologia , Regulação da Expressão Gênica , Humanos , Mola Hidatiforme/genética , Infertilidade Masculina/genética , Masculino , Placenta/fisiologia , Síndrome de Prader-Willi/genética , Gravidez
15.
Clin Dysmorphol ; 16(1): 65-66, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17159520

RESUMO

Karyotypic abnormalities involving the Y chromosome are common. The clinical spectrum associated with Y chromosome trisomy, tetrasomy or pentasomy is imprecise, as still very few cases have been reported. All cases, however, seem to exhibit some degree of mental retardation and minor facial dysmorphisms. The case we describe is only the fifth reported case of non-mosaic Y tetrasomy. This report and follow-up of a patient, between 4 months and 26 years of age, will certainly be helpful in better characterizing this karyotypic defect.


Assuntos
Cromossomos Humanos Y , Deficiência Intelectual/patologia , Poliploidia , Aberrações dos Cromossomos Sexuais , Adolescente , Adulto , Criança , Pré-Escolar , Seguimentos , Humanos , Lactente , Deficiência Intelectual/genética , Masculino
16.
Mol Cell Biol ; 26(22): 8347-56, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16954379

RESUMO

Landmark features of imprinted genes are differentially methylated domains (DMDs), in which one parental allele is methylated on CpG dinucleotides and the opposite allele is unmethylated. Genetic experiments in the mouse have shown that DMDs are required for the parent-specific expression of linked clusters of imprinted genes. To understand the mechanism whereby the differential methylation is established and maintained, we analyzed a series of transgenes containing DMD sequences and showed that imperfect tandem repeats from DMDs associated with the Snurf/Snrpn, Kcnq1, and Igf2r gene clusters govern transgene imprinting. For the Igf2r DMD the minimal imprinting signal is two unit copies of the tandem repeat. This imprinted transgene behaves identically to endogenous imprinted genes in Dnmt1o and Dnmt3L mutant mouse backgrounds. The primary function of the imprinting signal within the transgene DMD is to maintain, during embryogenesis and a critical period of genomic reprogramming, parent-specific DNA methylation states established in the germ line. This work advances our understanding of the imprinting mechanism by defining a genomic signal that dependably perpetuates an epigenetic state during postzygotic development.


Assuntos
Ilhas de CpG , Metilação de DNA , Genes myc , Impressão Genômica , Proteínas Nucleares/genética , Receptor IGF Tipo 2/genética , Animais , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/genética , Regulação da Expressão Gênica , Genes de Imunoglobulinas , Camundongos , Camundongos Transgênicos , Modelos Genéticos , Sequências de Repetição em Tandem
17.
Rev Med Suisse Romande ; 123(6): 397-400, 2003 Jun.
Artigo em Francês | MEDLINE | ID: mdl-15095681

RESUMO

Over the past 20 years, the use of recombinant growth hormone (rhGH) has become more frequent and the indications for this therapy extended to more common conditions than primary pituitary dysfunction. GH, a very strong anabolic agent, alters body growth and composition, and metabolic pathways. RhGH therapy seems to be beneficial in certain types of pathologies and surgical procedures, by preventing the deleterious effects due to catabolism and by increasing immune function, healing process and muscular strength. Several types of tumors have been studied to investigate the rhGH-related oncological risks. This article aims at reviewing the clinical studies focused on the possible association between rhGH and cancer.


Assuntos
Hormônio do Crescimento/fisiologia , Neoplasias/etiologia , Hormônio do Crescimento/efeitos adversos , Humanos
18.
Hum Genet ; 111(3): 284-9, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12215842

RESUMO

DNA sequences of mono-, di-, and trinucleotide repeats are prone to replication errors and thus constitute mutational hot spots. This is well illustrated by the occurrence of DNA microsatellite instability in tumors from patients affected by hereditary nonpolyposis colorectal cancer (HNPCC) resulting from a defect in a gene that participates in postreplicative DNA mismatch repair (MMR). We selected repeat sequences present within coding regions of four genes involved in either cell proliferation or promotion of apoptosis. These repeats consisted of (A)10 in the TGF beta RII, (G)8 in the BAX, (A)8 in the CASP1, and (CCA)7 in the APP genes. These repeats were analyzed in ten tumors from HNPCC patients carrying a germline pathogenic mutation in the MMR gene MLH1. For each tumor the rate of somatic replication errors was measured by sequencing 20-50 cloned PCR-amplified fragments. Substantial intertumor variations were observed in the pattern of repeat alterations, with error rates varying between 12% and 80% for TGF beta RII, 2% and 84% for BAX, 0% and 30% for CASP1, and 0% to 18% for APP. The BAX repeat error rate did not exceed 20% in nine of the ten tumors, in contrast to results from previous studies. High error rates in more than one gene in a same tumor suggested additive selective effects from inactivation of different pathways influencing tumorigenesis. Our methodology can contribute to define tumor characteristics and may, if applied to genes strongly involved in tumorigenesis, improve tumor classification and outcome prediction.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/genética , Mutação da Fase de Leitura , Repetições de Microssatélites , Proteínas Proto-Oncogênicas c-bcl-2 , Proteínas Adaptadoras de Transdução de Sinal , Precursor de Proteína beta-Amiloide/genética , Apoptose/genética , Pareamento Incorreto de Bases/genética , Proteínas de Transporte , Caspase 1/genética , Divisão Celular/genética , Reparo do DNA/genética , DNA de Neoplasias/genética , Mutação em Linhagem Germinativa , Humanos , Proteína 1 Homóloga a MutL , Proteínas de Neoplasias/genética , Proteínas Nucleares , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas/genética , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/genética , Proteína X Associada a bcl-2
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