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1.
J Intellect Disabil Res ; 64(12): 956-969, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33034087

RESUMO

BACKGROUND: Ultrarare Marshall-Smith and Malan syndromes, caused by changes of the gene nuclear factor I X (NFIX), are characterised by intellectual disability (ID) and behavioural problems, although questions remain. Here, development and behaviour are studied and compared in a cross-sectional study, and results are presented with genetic findings. METHODS: Behavioural phenotypes are compared of eight individuals with Marshall-Smith syndrome (three male individuals) and seven with Malan syndrome (four male individuals). Long-term follow-up assessment of cognition and adaptive behaviour was possible in three individuals with Marshall-Smith syndrome. RESULTS: Marshall-Smith syndrome individuals have more severe ID, less adaptive behaviour, more impaired speech and less reciprocal interaction compared with individuals with Malan syndrome. Sensory processing difficulties occur in both syndromes. Follow-up measurement of cognition and adaptive behaviour in Marshall-Smith syndrome shows different individual learning curves over time. CONCLUSIONS: Results show significant between and within syndrome variability. Different NFIX variants underlie distinct clinical phenotypes leading to separate entities. Cognitive, adaptive and sensory impairments are common in both syndromes and increase the risk of challenging behaviour. This study highlights the value of considering behaviour within developmental and environmental context. To improve quality of life, adaptations to environment and treatment are suggested to create a better person-environment fit.


Assuntos
Anormalidades Múltiplas/epidemiologia , Anormalidades Múltiplas/fisiopatologia , Doenças do Desenvolvimento Ósseo/epidemiologia , Doenças do Desenvolvimento Ósseo/fisiopatologia , Anormalidades Craniofaciais/epidemiologia , Anormalidades Craniofaciais/fisiopatologia , Deficiência Intelectual/epidemiologia , Deficiência Intelectual/fisiopatologia , Transtornos Mentais/epidemiologia , Displasia Septo-Óptica/epidemiologia , Displasia Septo-Óptica/fisiopatologia , Distúrbios da Fala/epidemiologia , Adaptação Psicológica , Adolescente , Adulto , Criança , Pré-Escolar , Comorbidade , Estudos Transversais , Feminino , Seguimentos , Humanos , Masculino , Transtornos Mentais/fisiopatologia , Países Baixos/epidemiologia , Fenótipo , Distúrbios da Fala/fisiopatologia , Síndrome , Adulto Jovem
2.
Br J Dermatol ; 180(1): 172-180, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30141192

RESUMO

BACKGROUND: Data on dermatological manifestations of cardiofaciocutaneous syndrome (CFCS) remain heterogeneous and almost without expert dermatological classification. OBJECTIVES: To describe the dermatological manifestations of CFCS; to compare them with the literature findings; to assess those discriminating CFCS from other RASopathies, including Noonan syndrome (NS) and Costello syndrome (CS); and to test for dermatological phenotype-genotype correlations. METHODS: We performed a 4-year, large, prospective, multicentric, collaborative dermatological and genetic study. RESULTS: Forty-five patients were enrolled. Hair abnormalities were ubiquitous, including scarcity or absence of eyebrows and wavy or curly hair in 73% and 69% of patients, respectively. Keratosis pilaris (KP), ulerythema ophryogenes (UO), palmoplantar hyperkeratosis (PPHK) and multiple melanocytic naevi (MMN; over 50 naevi) were noted in 82%, 44%, 27% and 29% of patients, respectively. Scarcity or absence of eyebrows, association of UO and PPHK, diffuse KP and MMN best differentiated CFCS from NS and CS. Oral acitretin may be highly beneficial for therapeutic management of PPHK, whereas treatment of UO by topical sirolimus 1% failed. No significant dermatological phenotype-genotype correlation was determined. CONCLUSIONS: A thorough knowledge of CFCS skin manifestations would help in making a positive diagnosis and differentiating CFCS from CS and NS.


Assuntos
Displasia Ectodérmica/diagnóstico , Insuficiência de Crescimento/diagnóstico , Cardiopatias Congênitas/diagnóstico , Acitretina/administração & dosagem , Administração Cutânea , Administração Oral , Adolescente , Criança , Pré-Escolar , Síndrome de Costello/diagnóstico , Diagnóstico Diferencial , Displasia Ectodérmica/tratamento farmacológico , Displasia Ectodérmica/genética , Fácies , Insuficiência de Crescimento/tratamento farmacológico , Insuficiência de Crescimento/genética , Feminino , França , Estudos de Associação Genética , Cardiopatias Congênitas/tratamento farmacológico , Cardiopatias Congênitas/genética , Humanos , MAP Quinase Quinase 1/genética , MAP Quinase Quinase 2/genética , Masculino , Mutação , Síndrome de Noonan/diagnóstico , Estudos Prospectivos , Proteínas Proto-Oncogênicas B-raf/genética , Sirolimo/administração & dosagem , Resultado do Tratamento , Adulto Jovem
3.
Br J Dermatol ; 180(6): 1438-1448, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30417923

RESUMO

BACKGROUND: Data on dermatological manifestations of Noonan syndrome (NS) remain heterogeneous and are based on limited dermatological expertise. OBJECTIVES: To describe the dermatological manifestations of NS, compare them with the literature findings, and test for dermatological phenotype-genotype correlations with or without the presence of PTPN11 mutations. METHODS: We performed a large 4-year, prospective, multicentric, collaborative dermatological and genetic study. RESULTS: Overall, 129 patients with NS were enrolled, including 65 patients with PTPN11-NS, 34 patients with PTPN11-NS with multiple lentigines (NSML), and 30 patients with NS who had a mutation other than PTPN11. Easy bruising was the most frequent dermatological finding in PTPN11-NS, present in 53·8% of patients. Multiple lentigines and café-au-lait macules (n ≥ 3) were present in 94% and 80% of cases of NSML linked to specific mutations of PTPN11, respectively. Atypical forms of NSML could be associated with NS with RAF1 or NRAS mutations. In univariate analysis, patients without a PTPN11 mutation showed (i) a significantly higher frequency of keratinization disorders (P = 0·001), including keratosis pilaris (P = 0·005), ulerythema ophryogenes (P = 0·0001) and palmar and/or plantar hyperkeratosis (P = 0·06, trend association), and (ii) a significantly higher frequency of scarce scalp hair (P = 0·035) and scarce or absent eyelashes (P = 0·06, trend association) than those with PTPN11 mutations. CONCLUSIONS: The cutaneous phenotype of NS with a PTPN11 mutation is generally mild and nonspecific, whereas the absence of a PTPN11 mutation is associated with a high frequency of keratinization disorders and hair abnormalities.


Assuntos
Estudos de Associação Genética , Síndrome de Noonan/complicações , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Dermatopatias/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Análise Mutacional de DNA , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Mutação , Síndrome de Noonan/genética , Fenótipo , Estudos Prospectivos , Adulto Jovem
4.
Am J Med Genet A ; 176(12): 2813-2818, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30365874

RESUMO

Pierpont syndrome is a rare and sporadic syndrome, including developmental delay, facial characteristics, and abnormal extremities. Recently, a recurrent de novo TBL1XR1 variant (c.1337A > G; p.Tyr446Cys) has been identified in eight patients by whole-exome sequencing. A dominant-negative effect of this mutation is strongly suspected, since patients with TBL1XR1 deletion and other variants predicting loss of function do not share the same phenotype. We report two patients with typical Pierpont-like syndrome features. Exome sequencing allowed identifying a de novo heterozygous missense TBL1XR1 variant in both patients, different from those already reported: p.Cys325Tyr and p.Tyr446His. The localization of these mutations and clinical features of Pierpont-like syndrome suggest that their functional consequences are comparable with the recurrent mutation previously described, and provided additional data to understand molecular mechanisms of TBL1XR1 anomalies.


Assuntos
Anormalidades Múltiplas/diagnóstico , Anormalidades Múltiplas/genética , Substituição de Aminoácidos , Mutação , Proteínas Nucleares/genética , Fenótipo , Receptores Citoplasmáticos e Nucleares/genética , Proteínas Repressoras/genética , Adolescente , Alelos , Encéfalo/anormalidades , Encéfalo/diagnóstico por imagem , Hibridização Genômica Comparativa , Fácies , Testes Genéticos , Genótipo , Humanos , Imageamento por Ressonância Magnética , Masculino , Síndrome , Ultrassonografia
5.
Ann R Coll Surg Engl ; 97(8): 589-91, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26492905

RESUMO

INTRODUCTION: With an increase in life expectancy in 'developed' countries, the number of elderly patients receiving joint injections for arthritis is increasing. There are legitimate concerns about an increased risk of thromboembolism if anticoagulation is stopped or reversed for such an injection. Despite being a common dilemma, the literature on this issue is scarce. METHODS: We undertook 2,084 joint injections of the knee and shoulder in 1,714 patients between August 2008 and December 2013. Within this cohort, we noted 41 patients who were taking warfarin and followed them immediately after joint injection in the clinic or radiology department, looking carefully for complications. Then, we sought clinical follow-up, correspondence, and imaging evidence for 4 weeks, looking for complications from these joint injections. We recorded International Normalised Ratio (INR) values before injection. RESULTS: No complications were associated with the procedure after any joint injection. The radiologists who undertook ultrasound-guided injections to shoulders re-scanned the joints looking for haemarthroses: they found none. A similar outcome was noted clinically after injections in the outpatient setting. CONCLUSION: With a mean INR of 2.77 (range, 1.7-5.5) and a maximum INR within this group of 5.5, joint injections to the shoulder and knee can be undertaken safely in primary or secondary care settings despite the patient taking warfarin.


Assuntos
Anti-Inflamatórios/administração & dosagem , Artrite/tratamento farmacológico , Fibrilação Atrial/complicações , Coeficiente Internacional Normatizado/normas , Tromboembolia Venosa/prevenção & controle , Varfarina/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/uso terapêutico , Artrite/complicações , Feminino , Seguimentos , Humanos , Injeções Intra-Articulares/normas , Articulação do Joelho , Masculino , Estudos Retrospectivos , Articulação do Ombro , Resultado do Tratamento , Tromboembolia Venosa/etiologia
6.
Bone Joint J ; 96-B(8): 1005-15, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25086114

RESUMO

Intravenous tranexamic acid (TXA) has been shown to be effective in reducing blood loss and the need for transfusion after joint replacement. Recently, there has been interest in applying it topically before the closure of surgical wounds. This has the advantages of ease of application, maximum concentration at the site of bleeding, minimising its systemic absorption and, consequently, concerns about possible side-effects. We conducted a systematic review and meta-analysis which included 14 randomised controlled trials (11 in knee replacement, two in hip replacement and one in both) which investigated the effect of topical TXA on blood loss and rates of transfusion. Topical TXA significantly reduced the rate of blood transfusion (total knee replacement: risk ratio (RR) 4.51; 95% confidence interval (CI): 3.02 to 6.72; p < 0.001 (nine trials, I(2) = 0%); total hip replacement: RR 2.56; 95% CI: 1.32 to 4.97, p = 0.004 (one trial)). The rate of thromboembolic events with topical TXA were similar to those found with a placebo. Indirect comparison of placebo-controlled trials of topical and intravenous TXA indicates that topical administration is superior to the intravenous route. In conclusion, topical TXA is an effective and safe method of reducing the need for blood transfusion after total knee and hip replacement. Further research is required to find its optimum dose for topical use.


Assuntos
Antifibrinolíticos/administração & dosagem , Artroplastia de Quadril/métodos , Artroplastia do Joelho/métodos , Hemorragia Pós-Operatória/prevenção & controle , Ácido Tranexâmico/administração & dosagem , Administração Tópica , Transfusão de Sangue/estatística & dados numéricos , Relação Dose-Resposta a Droga , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Trombose Venosa/induzido quimicamente
7.
Ann R Coll Surg Engl ; 96(1): 115E-117E, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24417860

RESUMO

We report a fatality due to massive gastrointestinal haemorrhage in a patient receiving prophylactic dabigatran etexilate following a total hip replacement. A 79-year-old woman was commenced on dabigatran for venous thromboembolic prophylaxis following a total hip replacement. She presented again four days after surgery with haematemesis and hypotension but her coagulopathy could not be corrected, leading to her death. This case highlights the lack of reversal agent for dabigatran etexilate that resulted in this fatal complication.


Assuntos
Antitrombinas/efeitos adversos , Benzimidazóis/efeitos adversos , Hemorragia Gastrointestinal/induzido quimicamente , Piridinas/efeitos adversos , Idoso , Artroplastia de Quadril , Dabigatrana , Evolução Fatal , Feminino , Humanos , Tromboembolia Venosa/prevenção & controle
9.
Clin Genet ; 84(6): 507-21, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23506379

RESUMO

The association of marfanoid habitus (MH) and intellectual disability (ID) has been reported in the literature, with overlapping presentations and genetic heterogeneity. A hundred patients (71 males and 29 females) with a MH and ID were recruited. Custom-designed 244K array-CGH (Agilent®; Agilent Technologies Inc., Santa Clara, CA) and MED12, ZDHHC9, UPF3B, FBN1, TGFBR1 and TGFBR2 sequencing analyses were performed. Eighty patients could be classified as isolated MH and ID: 12 chromosomal imbalances, 1 FBN1 mutation and 1 possibly pathogenic MED12 mutation were found (17%). Twenty patients could be classified as ID with other extra-skeletal features of the Marfan syndrome (MFS) spectrum: 4 pathogenic FBN1 mutations and 4 chromosomal imbalances were found (2 patients with both FBN1 mutation and chromosomal rearrangement) (29%). These results suggest either that there are more loci with genes yet to be discovered or that MH can also be a relatively non-specific feature of patients with ID. The search for aortic complications is mandatory even if MH is associated with ID since FBN1 mutations or rearrangements were found in some patients. The excess of males is in favour of the involvement of other X-linked genes. Although it was impossible to make a diagnosis in 80% of patients, these results will improve genetic counselling in families.


Assuntos
Testes Genéticos/métodos , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Síndrome de Marfan/diagnóstico , Síndrome de Marfan/genética , Adolescente , Adulto , Criança , Pré-Escolar , Hibridização Genômica Comparativa , Análise Citogenética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Estudos Prospectivos , Análise de Sequência de DNA , Inativação do Cromossomo X , Adulto Jovem
10.
J Bone Joint Surg Br ; 93(12): 1577-85, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22161917

RESUMO

We conducted a systematic review and meta-analysis of randomised controlled trials evaluating the effect of tranexamic acid (TXA) upon blood loss and transfusion in primary total knee replacement. The review used the generic evaluation tool designed by the Cochrane Bone, Joint and Muscle Trauma Group. A total of 19 trials were eligible: 18 used intravenous administration, one also evaluated oral dosing and one trial evaluated topical use. TXA led to a significant reduction in the proportion of patients requiring blood transfusion (risk ratio (RR) 2.56, 95% confidence interval (CI) 2.1 to 3.1, p < 0.001; heterogeneity I(2) = 75%; 14 trials, 824 patients). Using TXA also reduced total blood loss by a mean of 591 ml (95% CI 536 to 647, p < 0.001; I(2) = 78%; nine trials, 763 patients). The clinical interpretation of these findings is limited by substantial heterogeneity. However, subgroup analysis of high-dose (> 4 g) TXA showed a plausible consistent reduction in blood transfusion requirements (RR 5.33; 95% CI 2.44 to 11.65, p < 0.001; I(2) = 0%), a finding that should be confirmed by a further well-designed trial. The current evidence from trials does not support an increased risk of deep-vein thrombosis (13 trials, 801 patients) or pulmonary embolism (18 trials, 971 patients) due to TXA administration.


Assuntos
Antifibrinolíticos/uso terapêutico , Artroplastia do Joelho/efeitos adversos , Perda Sanguínea Cirúrgica/prevenção & controle , Transfusão de Sangue/estatística & dados numéricos , Hemorragia Pós-Operatória/prevenção & controle , Ácido Tranexâmico/uso terapêutico , Adulto , Humanos , Embolia Pulmonar/induzido quimicamente , Ensaios Clínicos Controlados Aleatórios como Assunto , Ácido Tranexâmico/efeitos adversos , Resultado do Tratamento , Trombose Venosa/induzido quimicamente
11.
Arch Pediatr ; 18(12): 1297-1301, 2011 Dec.
Artigo em Francês | MEDLINE | ID: mdl-21963371

RESUMO

Genetic syndromes that mimic congenital infections must be recognized because of the associated risk of recurrence. We describe a male infant who was born with the association of intra-uterine growth retardation, microcephaly, intracranial calcifications, white matter abnormalities, microphtalmy, bilateral cataract, and hearing loss. Congenital cytomegalovirus (CMV) infection was suspected, but serologic CMV markers were not decisive (IgG+/IgM-). His half-sister (same father) presented a similar phenotype. Therefore, the diagnosis of congenital CMV infection was questioned and a genetic hypothesis was suggested. In 1983, Baraitser et al. first described two brothers with microcephaly and intracranial calcifications and negative TORCH analysis. Later, a number of authors reported children in whom detailed investigation failed to objectively confirm an intra-uterine infective agent. Clinical features include severe postnatal microcephaly, seizures, and pronounced developmental arrest. These cases have been considered to define a distinct autosomal recessive disorder first named pseudo-Torch syndrome. The family described herein is different from the cases previously described with a suspected autosomal dominant inheritance, severe ophtalmological abnormalities, and unusual brain imaging.


Assuntos
Anormalidades Múltiplas/genética , Doenças Autoimunes do Sistema Nervoso/congênito , Anormalidades Múltiplas/patologia , Adolescente , Doenças Autoimunes do Sistema Nervoso/genética , Encéfalo/anormalidades , Calcinose/genética , Catarata/genética , Pré-Escolar , Diagnóstico Diferencial , Feminino , Perda Auditiva/genética , Humanos , Masculino , Microcefalia/genética , Malformações do Sistema Nervoso/genética , Fatores de Risco , Convulsões/genética , Irmãos
13.
Hum Reprod Update ; 17(4): 476-94, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21486858

RESUMO

BACKGROUND: Complex chromosomal rearrangements (CCRs) describe structural rearrangements, essentially translocations, involving at least three breakpoints on two or more chromosomes. Although they are rare in humans, their clinical identification is important since CCR carriers can display various phenotypes which include phenotypically normal subjects, infertile males and patients with mental retardation and/or congenital abnormalities. The rearrangement can be de novo or familial. The use of fluorescent in situ hybridization assays and molecular techniques for the characterization of CCRs have indicated that the rearrangements could be more complex than initially assumed. Accumulating data have revealed that the mechanisms underlying the genesis of CCRs remain elusive. METHODS: We performed a large PubMed search in order to summarize the current knowledge in this field and address important aspects of CCR formation and meiotic behavior, highlighting the complexity of these rearrangements at the chromosomal and genomic level. RESULTS: The review of published data indicates that the complexity of CCRs is becoming increasingly known, thanks to the application of more and more efficient molecular techniques. These approaches have allowed the precise sequence analysis of breakpoints and the identification of insertions, deletions, inversions and recombination events. New models have been proposed for the formation of CCRs, based on replication-based mechanisms and specific sequence elements. Their meiotic behavior has been discussed in the light of these new molecular data. CONCLUSIONS: Despite the increasing understanding of the mechanisms involved in their genesis, CCRs arise as unique, complex events for which the genetic and reproductive counseling of carriers remains a challenge.


Assuntos
Aberrações Cromossômicas , Rearranjo Gênico , Meiose , Feminino , Humanos , Masculino , Translocação Genética
14.
Clin Genet ; 79(3): 225-35, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20950397

RESUMO

Since the first reports of polyglutamine-binding protein 1 (PQBP1) mutations in Renpenning syndrome and related disorders, the spectrum of PQBP1-linked clinical manifestations has been outlined from rare published case reports. The phenotypic description is often obtained from medical archives, and therefore, heterogeneous. Moreover, some aspects such as brain imaging or cognitive and behavioral functioning are rarely described. In this study, 13 PQBP1-mutated French patients were subjected to a standardized clinical, cognitive and behavioral assessment. Physical measurements of their relatives were also collected. We report on a recognizable clinical and radiological phenotype. All patients presented with microcephaly, leanness and mild short stature, relative to familial measurements. Three new clinical features are described: upper back progressive muscular atrophy, metacarpophalangeal ankylosis of the thumb and velar dysfunction. The specific facial dysmorphic features included at least four of the following signs: long triangular face, large ridged nose, half-depilated eyebrows, dysplastic or protruding ears and rough slightly sparse hair. An over-aged appearance was noticed in elderly patients. Cortical gyrification was normal based on available magnetic brain imaging of six patients. PQBP1-linked microcephaly (or Renpenning syndrome) is an X-linked mental retardation syndrome, which has clinically recognizable features.


Assuntos
Proteínas de Transporte/genética , Mutação , Proteínas Nucleares/genética , Fenótipo , Adolescente , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Paralisia Cerebral/complicações , Paralisia Cerebral/diagnóstico por imagem , Paralisia Cerebral/genética , Paralisia Cerebral/patologia , Criança , Pré-Escolar , Transtornos Cognitivos/etiologia , Proteínas de Ligação a DNA , Feminino , França , Genótipo , Humanos , Masculino , Deficiência Intelectual Ligada ao Cromossomo X/complicações , Deficiência Intelectual Ligada ao Cromossomo X/diagnóstico por imagem , Deficiência Intelectual Ligada ao Cromossomo X/genética , Deficiência Intelectual Ligada ao Cromossomo X/patologia , Gravidez , Radiografia , Adulto Jovem
15.
Hum Mutat ; 31(2): 113-26, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19894250

RESUMO

Cockayne syndrome is an autosomal recessive multisystem disorder characterized principally by neurological and sensory impairment, cachectic dwarfism, and photosensitivity. This rare disease is linked to mutations in the CSB/ERCC6 and CSA/ERCC8 genes encoding proteins involved in the transcription-coupled DNA repair pathway. The clinical spectrum of Cockayne syndrome encompasses a wide range of severity from severe prenatal forms to mild and late-onset presentations. We have reviewed the 45 published mutations in CSA and CSB to date and we report 43 new mutations in these genes together with the corresponding clinical data. Among the 84 reported kindreds, 52 (62%) have mutations in the CSB gene. Many types of mutations are scattered along the whole coding sequence of both genes, but clusters of missense mutations can be recognized and highlight the role of particular motifs in the proteins. Genotype-phenotype correlation hypotheses are considered with regard to these new molecular and clinical data. Additional cases of molecular prenatal diagnosis are reported and the strategy for prenatal testing is discussed. Two web-based locus-specific databases have been created to list all identified variants and to allow the inclusion of future reports (www.umd.be/CSA/ and www.umd.be/CSB/).


Assuntos
Síndrome de Cockayne/genética , DNA Helicases/genética , Enzimas Reparadoras do DNA/genética , Mutação/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Síndrome de Cockayne/diagnóstico , DNA Helicases/química , Enzimas Reparadoras do DNA/química , Bases de Dados Genéticas , Estudos de Associação Genética , Humanos , Dados de Sequência Molecular , Proteínas de Ligação a Poli-ADP-Ribose , Polimorfismo Genético , Alinhamento de Sequência , Relação Estrutura-Atividade , Fatores de Transcrição/química
17.
Mol Hum Reprod ; 13(10): 751-6, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17913851

RESUMO

Paracentric inversions (PAI) are structural chromosomal rearrangements generally considered to be harmless. Nevertheless, cases of viable recombinants have been reported, indicating the interest of studying the meiotic behaviour of these chromosomal abnormalities. To date, the few studies reported have been performed using either the human-hamster fertilization system or fluorescence in situ hybridization with centromeric or telomeric DNA probes. In order to improve the assessment of meiotic segregation in PAI, we present a new strategy based on the use of bacterial artificial chromosome (BAC) probes which allow a precise localization of chromosome breakpoints and the identification of all meiotic products in human sperm. Sperm samples from carriers of an inv(5) and an inv(14) were used to test this new high-resolution procedure.


Assuntos
Quebra Cromossômica , Inversão Cromossômica/genética , Espermatozoides/metabolismo , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 5 , Humanos , Hibridização in Situ Fluorescente , Masculino , Meiose/genética , Modelos Genéticos
18.
Am J Hum Genet ; 80(5): 966-70, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17436251

RESUMO

Crisponi syndrome is a rare autosomal recessive disorder characterized by congenital muscular contractions of facial muscles, with trismus in response to stimuli, dysmorphic features, bilateral camptodactyly, major feeding and respiratory difficulties, and access of hyperthermia leading to death in the first months of life. The overlap with Stuve-Wiedemann syndrome (SWS) is striking, but the two conditions differ in that congenital lower limb bowing is absent in Crisponi syndrome, whereas it is a cardinal feature of SWS. We report here the exclusion of the leukemia inhibitory factor receptor gene in Crisponi syndrome and the identification of homozygote or compound heterozygote cytokine receptor-like factor 1 (CRLF1) mutations in four children from three unrelated families. The four mutations were located in the immunoglobulin-like and type III fibronectin domains, and three of them predicted premature termination of translation. Using real-time quantitative polymerase chain reaction, we found a significant decrease in CRLF1 mRNA expression in patient fibroblasts, which is suggestive of a mutation-mediated decay of the abnormal transcript. CRLF1 forms a heterodimer complex with cardiotrophin-like cytokine factor 1, and this heterodimer competes with ciliary neurotrophic factor for binding to the ciliary neurotrophic factor receptor (CNTFR) complex. The identification of CRLF1 mutations in Crisponi syndrome supports the key role of the CNTFR pathway in the function of the autonomic nervous system.


Assuntos
Anormalidades Múltiplas/genética , Mutação , Receptores de Citocinas/genética , Sudorese/genética , Adolescente , Sequência de Bases , Criança , Temperatura Baixa/efeitos adversos , Contratura/congênito , Contratura/genética , Feminino , Genes Recessivos , Humanos , Recém-Nascido , Masculino , Contração Muscular/genética , Linhagem , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Síndrome
19.
Hum Reprod ; 21(12): 3193-8, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16917122

RESUMO

t(13;15) and t(14;15) are two rare Robertsonian translocations. Meiotic segregation was studied in four males heterozygous for the rare Robertsonian translocations t(13;15) and t(14;15). Both locus-specific probes (LSPs) and whole chromosome painting (WCP) probes, specific to chromosomes 13, 14 and 15, were used in this study. The number of spermatozoa scored for each carrier ranged from 891 to 5000. The frequencies of normal and balanced sperm resulting from the alternate mode of segregation ranged from 77.6 to 92.8%, confirming the prevalence of alternate segregation over other segregation modes in all Robertsonian translocations. The incidences of unbalanced complements ranged from 6.7 to 20.4%, with a significant excess of disomy rates over the complementary frequencies of nullisomy. This variability might reflect differences in the location of breakpoints in translocated chromosomes, leading to the variable production of unbalanced gametes and the variable alterations of semen parameters in Robertsonian translocation carriers.


Assuntos
Cromossomos Humanos Par 13 , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 15 , Hibridização in Situ Fluorescente/métodos , Meiose , Espermatozoides/ultraestrutura , Translocação Genética , Adulto , Segregação de Cromossomos , Heterozigoto , Humanos , Masculino
20.
Hum Reprod ; 21(5): 1166-71, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16439506

RESUMO

BACKGROUND: The t(14;22) remains one of the rare Robertsonian translocations observed in human, with an occurrence estimated at 1.2%. Three cases of rare Robertsonian translocation t(14;22) were investigated for meiotic segregation in sperm samples from male carriers using the fluorescent in situ hybridization (FISH) procedure. The three carriers included two men with an abnormal semen analysis and one with normal semen parameters. METHODS: Both locus-specific probes and whole-chromosome painting probes, specific for chromosomes 14 and 22, were used in this study. The number of spermatozoa scored for each probe set ranged from 3279 to 10,024. RESULTS: In the three carriers, similar frequencies, ranging from 78.53 to 81.76%, were found for normal and balanced spermatozoa resulting from alternate segregation. The total proportion of unbalanced spermatozoa resulting from adjacent modes of segregation ranged from 17.59 to 20.94%. CONCLUSION: This finding confirmed the predominance of alternate segregation over other segregation types in all Robertsonian translocations and indicates a higher production of imbalances in the t(14;22) than in most of the Robertsonian translocations previously analysed. This could be related to the variable location of breakpoints in Robertsonian translocations. This breakpoint diversity could also play a role in the differences in reproductive status observed in male carriers of Robertsonian translocations.


Assuntos
Segregação de Cromossomos , Cromossomos Humanos Par 14/genética , Cromossomos Humanos Par 22/genética , Espermatozoides/citologia , Translocação Genética/genética , Adulto , Heterozigoto , Humanos , Hibridização in Situ Fluorescente , Masculino , Meiose/genética
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