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1.
BMC Psychiatry ; 21(1): 72, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33541313

RESUMO

BACKGROUND: ADHD is neurodevelopmental disorder which persists into adulthood. Presently, therapeutic approaches are mainly pharmacological and psychological whilst the role, scope and approaches of occupational therapists have not been adequately described. RESULTS: In this consensus statement we propose that by assessing specific aspects of a person's occupation, occupational therapists can deploy their unique skills in providing specialist interventions for adults with ADHD. We also propose a framework with areas where occupational therapists can focus their assessments and give practice examples of specific interventions. CONCLUSIONS: Occupational therapists have much to offer in providing interventions for adults with ADHD. A unified and flexible approach when working with adults with ADHD is most appropriate and further research on occupational therapy interventions is needed.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Terapia Ocupacional , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/terapia , Consenso , Humanos , Terapeutas Ocupacionais , Reino Unido
2.
Am J Med Genet A ; 176(5): 1238-1244, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29681091

RESUMO

Pathogenic variants in Zinc Finger DHHC-Type Containing 9 (ZDHHC9) gene have been identified as the cause of X-linked intellectual disability (XLID) in a small number of families. There are a total of 11 reported pathogenic variants in ZDHHC9 in the literature. The majority of reported variants are familial point mutations. There is one report of XLID associated with a de novo mutation in ZDHHC9, and one family with intragenic deletion within ZDHHC9 detected by array CGH. Although initial reports of families with ZDHHC9 pathogenic variants suggested a nonsyndromic XLID, more recent reports suggest a syndromic phenotype with facial dysmorphism. Here we report four patients with pathogenic variants in ZDHHC9, a family with two siblings and their maternal uncle who presented with XLID due to intragenic deletion of ZDHHC9 detected by array CGH and an 11-year-old boy with a de novo pathogenic missense variant in ZDHHC9, which is the first recurrent ZDHHC9 mutation. Our patients had some distinctive facial features in common, including elongated and down-slanting palpebral fissures and high hairline. Marfanoid habitus and seizures that have been previously reported in association with pathogenic variants in ZDHHC9 were absent in our cohort. Clinical information on patients with ZDHHC9-associated XLID is very scarce. New reports of families with detailed clinical description will add to the existing knowledge and help understand the condition better.


Assuntos
Aciltransferases/genética , Estudos de Associação Genética , Deficiência Intelectual Ligada ao Cromossomo X/diagnóstico , Deficiência Intelectual Ligada ao Cromossomo X/genética , Mutação , Fenótipo , Adolescente , Alelos , Criança , Hibridização Genômica Comparativa , Fácies , Feminino , Estudos de Associação Genética/métodos , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Masculino , Linhagem
3.
Am J Med Genet A ; 176(7): 1578-1586, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29736964

RESUMO

BACKGROUND: Idiopathic Juvenile Osteoporosis (IJO) refers to significantly lower than expected bone mass manifesting in childhood with no identifiable aetiology. IJO classically presents in early pubertal period with multiple fractures including metaphyseal and vertebral crush fractures, and low bone-mass. METHODS: Here we describe two patients and provide information on their clinical phenotype, genotype and bone material analysis in one of the patients. RESULTS: Patient 1: 40-year old adult male diagnosed with IJO in childhood who re-presented with a hip fracture as an adult. Genetic analysis identified a pathogenic PLS3 hemizygous variant, c.1765del in exon 16. Patient 2: 15-year old boy with multiple vertebral fractures and bone biopsy findings suggestive of IJO who also has a diagnosis of autism spectrum disorder. Genetic analysis identified a maternally inherited PLS3 pathogenic c.1295T>A variant in exon 12. Analyses of the transiliac bone sample revealed severe reduction of trabecular volume and bone turnover indices and elevated bone matrix mineralisation. DISCUSSION: We propose that genetic testing for PLS3 should be undertaken in patients presenting with a current or previous history of IJO as this has implications for genetic counselling and cascade screening. The extensive evaluation of the transiliac biopsy sample of Patient 2 revealed a novel bone phenotype. CONCLUSION: This report includes a review of IJO and genetic causes of osteoporosis, and suggests that existing cases of IJO should be screened for PLS3. Through analysis of bone material properties in Patient 2, we can conclude that PLS3 does have a role in bone mineralisation.


Assuntos
Calcificação Fisiológica , Doenças Genéticas Ligadas ao Cromossomo X/genética , Glicoproteínas de Membrana/genética , Proteínas dos Microfilamentos/genética , Mutação , Osteoporose/genética , Adolescente , Adulto , Feminino , Doenças Genéticas Ligadas ao Cromossomo X/patologia , Humanos , Masculino , Osteoporose/patologia , Linhagem , Fenótipo , Prognóstico
4.
Am J Med Genet A ; 170A(2): 476-481, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26471105

RESUMO

We report a sibling-pair and a 4-year old child from two families with an atypical presentation in Osteogenesis imperfecta (OI). In the sib-pair, the older sibling initially came to medical attention due to a fracture history (Patient 1) and she was shown to have a COL1A2 mutation. In addition, she also had developmental delay, facial dysmorphism, and a history of frequent infections which led to a search for an alternate diagnosis. ArrayCGH revealed a 4.3 Mb duplication on chromosome 19q13.42q13.43, which was confirmed by FISH analysis. On further familial analysis, the younger sibling who had no previous fracture history was also found to have the COL1A2 mutation and tested positive for the 19q13.42q13.43 duplication (Patient 2). The 19q13 duplication appears to be the cause of intellectual disability in these siblings but given that this is a chromosomal duplication, it is still possible that there is an as yet unidentified cause that may account for the combined phenotype in this family. Patient 3 was a 4-year old child presenting with a femoral fracture, blue sclerae, developmental delay, and joint hypermobility. Genetic analyses confirmed a COL1A2 mutation but also revealed an 8.8 Mb deletion of 11q24.2q25, confirmed by G-band chromosome analysis. We discuss the differing phenotypes in patients presenting with atypical OI and stress the need to consider ancillary investigations in individuals presenting with heterogeneous phenotypic symptoms, not entirely attributable to OI.


Assuntos
Colágeno Tipo I/genética , Variações do Número de Cópias de DNA , Mutação/genética , Osteogênese Imperfeita/genética , Osteogênese Imperfeita/patologia , Adolescente , Pré-Escolar , Cromossomos Humanos Par 11/genética , Hibridização Genômica Comparativa , Feminino , Testes Genéticos , Humanos , Recém-Nascido , Masculino
5.
J Hum Genet ; 60(6): 313-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25761574

RESUMO

Interstitial deletions of the long arm of chromosome 20 are rarely reported in the literature. We report a 2-year-old child with a 2.6 Mb deletion of 20q13.32-q13.33, detected by microarray-based comparative genomic hybridization, who presented with poor growth, feeding difficulties, abnormal subcutaneous fat distribution with the lack of adipose tissue on clinical examination, facial dysmorphism and low bone mass. This report adds to rare publications describing constitutional aberrations of chromosome 20q, and adds further evidence to the fact that deletion of the GNAS complex may not always be associated with an Albright's hereditary osteodystrophy phenotype as described previously.


Assuntos
Doenças do Desenvolvimento Ósseo/diagnóstico , Cromossomos Humanos Par 20/genética , Transtornos de Alimentação na Infância/diagnóstico , Transtornos do Crescimento/diagnóstico , Doenças do Desenvolvimento Ósseo/genética , Pré-Escolar , Deleção Cromossômica , Hibridização Genômica Comparativa , Transtornos de Alimentação na Infância/genética , Estudos de Associação Genética , Transtornos do Crescimento/genética , Humanos , Masculino
6.
Am J Med Genet A ; 164A(5): 1222-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24458726

RESUMO

We describe two unrelated patients with molecularly confirmed Sotos syndrome with multiple subpleural blebs and pneumothorax. We propose this as a new association. Patient 1 is a 3-year-old boy with a 1.9 Mb interstitial deletion of the long arm of chromosome 5, with breakpoints at q35.2 and q35.3, encompassing NSD1 and Patient 2 is a 9-year-old girl with a de novo truncating mutation within NSD1. Both patients presented with sudden onset dyspnea due to a unilateral pneumothorax: Patient 1 at the age of 18 months and Patient 2 at 9 years. In both, the pneumothorax recurred following removal of the chest drain and, on further investigations, multiple subpleural blebs were identified necessitating a pleurodesis and tissue resection. This is the first report of multiple subpleural blebs leading to pneumothorax in association with Sotos syndrome. Given the similar and unusual presentation in the two affected patients, we suggest that this may be a real association, albeit a rare one. While screening would not be advocated for such a rare association, we recommend that clinicians consider pneumothorax in patients with Sotos syndrome and sudden onset of dyspnea and are aware that it may be refractory to first line treatment.


Assuntos
Pneumotórax/patologia , Síndrome de Sotos/diagnóstico , Biópsia , Pré-Escolar , Deleção Cromossômica , Cromossomos Humanos Par 5 , Hibridização Genômica Comparativa , Fácies , Feminino , Histona Metiltransferases , Histona-Lisina N-Metiltransferase , Humanos , Lactente , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Proteínas Nucleares/genética , Fenótipo , Pneumotórax/diagnóstico , Síndrome de Sotos/genética , Toracoscópios , Tomografia Computadorizada por Raios X
7.
Nat Biotechnol ; 25(2): 207-15, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17287758

RESUMO

The application of human embryonic stem cells (HESCs) to provide differentiated cells for regenerative medicine will require the continuous maintenance of the undifferentiated stem cells for long periods in culture. However, chromosomal stability during extended passaging cannot be guaranteed, as recent cytogenetic studies of HESCs have shown karyotypic aberrations. The observed karyotypic aberrations probably reflect the progressive adaptation of self-renewing cells to their culture conditions. Genetic change that increases the capacity of cells to proliferate has obvious parallels with malignant transformation, and we propose that the changes observed in HESCs in culture reflect tumorigenic events that occur in vivo, particularly in testicular germ cell tumors. Further supporting a link between culture adaptation and malignancy, we have observed the formation of a chromosomal homogeneous staining region in one HESC line, a genetic feature almost a hallmark of cancer cells. Identifying the genes critical for culture adaptation may thus reveal key players for both stem cell maintenance in vitro and germ cell tumorigenesis in vivo.


Assuntos
Técnicas de Cultura de Células/métodos , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Aberrações Cromossômicas , Células-Tronco Embrionárias/patologia , Células-Tronco Embrionárias/fisiologia , Adaptação Fisiológica/genética , Diferenciação Celular/genética , Humanos , Modelos Genéticos
8.
J Pediatr Endocrinol Metab ; 32(9): 959-967, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31301676

RESUMO

Background Type I pseudohypoaldosteronism (PHA1) is a rare condition characterised by profound salt wasting, hyperkalaemia and metabolic acidosis due to renal tubular resistance to aldosterone (PHA1a) or defective sodium epithelial channels (PHA1b or systemic PHA). Our aim was to review the clinical presentation related to the genotype in patients with PHA1. Methods A questionnaire-based cross-sectional survey was undertaken through the British Society of Paediatric Endocrinology and Diabetes (BSPED) examining the clinical presentation and management of patients with genetically confirmed PHA1. We also reviewed previously reported patients where genotypic and phenotypic information were reported. Results Genetic confirmation was made in 12 patients with PHA1; four had PHA1a, including one novel mutation in NR3C2; eight had PHA1b, including three with novel mutations in SCNN1A and one novel mutation in SCNN1B. It was impossible to differentiate between types of PHA1 from early clinical presentation or the biochemical and hormonal profile. Patients presenting with missense mutations of SCNN1A and SCNN1B had a less marked rise in serum aldosterone suggesting preservation in sodium epithelial channel function. Conclusions We advocate early genetic testing in patients with presumed PHA1, given the challenges in differentiating between patients with PHA1a and PHA1b. Clinical course differs between patients with NR3C2 and SCNN1A mutations with a poorer prognosis in those with multisystem PHA. There were no obvious genotype-phenotype correlations between mutations on the same gene in our cohort and others, although a lower serum aldosterone may suggest a missense mutation in SCNN1 in patients with PHA1b.


Assuntos
Biomarcadores/análise , Canais Epiteliais de Sódio/genética , Mutação de Sentido Incorreto , Pseudo-Hipoaldosteronismo/genética , Receptores de Mineralocorticoides/genética , Aldosterona/sangue , Criança , Pré-Escolar , Estudos Transversais , Feminino , Seguimentos , Estudos de Associação Genética , Genótipo , Humanos , Recém-Nascido , Masculino , Fenótipo , Prognóstico , Pseudo-Hipoaldosteronismo/classificação , Pseudo-Hipoaldosteronismo/patologia
9.
Clin Dysmorphol ; 27(2): 36-41, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29240611

RESUMO

Structural rearrangements of chromosome band 1p31p32 are rare, and their phenotypic consequences remain poorly delineated. Up to 12 patients with learning difficulties, developmental delay, multiple congenital anomalies and microdeletion of the chromosome band 1p31p32 have been described. Inheritance of this deletion has not been reported previously. We describe the inheritance of the 1p32 deletion and discuss the relevance of this deletion to the described phenotype. The differences in clinical and molecular characteristics between the proband and other published reports are reviewed. Patients were evaluated in Genetics Clinic with history, examination and investigation. The existing literature on interstitial deletions of 1p was reviewed. Here, we report on a three-generation family, where the index patient was an adult female with learning difficulty, dysmorphic features, microcephaly, ambiguous genitalia, congenital hip dislocation and brachydactyly in whom a maternally inherited 1.45 Mbp interstitial deletion was detected at 1p32.3. Both her mother and maternal grandmother have learning difficulties and dysmorphic features. There are 14 OMIM genes in the deleted region including LRP8 and DMRTB1. The NFIA gene is not deleted in this family. The first report of a familial 1p32 microdeletion in three generations of a family carrying the smallest reported a deletion involving this region and brachydactyly as a previously unreported feature.


Assuntos
Anormalidades Múltiplas/genética , Deleção Cromossômica , Deficiências do Desenvolvimento/genética , Microcefalia/genética , Anormalidades Múltiplas/fisiopatologia , Adulto , Cromossomos Humanos Par 1/genética , Hibridização Genômica Comparativa , Proteínas de Ligação a DNA/genética , Deficiências do Desenvolvimento/fisiopatologia , Feminino , Humanos , Proteínas Relacionadas a Receptor de LDL/genética , Masculino , Microcefalia/fisiopatologia , Linhagem , Fenótipo , Fatores de Transcrição/genética
10.
Bone Rep ; 8: 156-162, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29955634

RESUMO

OBJECTIVES: Osteogenesis Imperfecta (OI) is a heterogeneous condition mainly characterised by bone fragility; intelligence is reported to be normal. However, a minority of children seen also show symptomology consistent with an 'Autism Spectrum Disorder'. A joint genetics and psychology research study was undertaken to identify these patients using 'Gold Standard' research tools: Autism Diagnostic Inventory Revised (ADI-R); Autism Diagnostic Observation Schedule (ADOS) and undertake genetic analyses in them. METHOD: A cohort of n = 7 children with autistic traits and severe/complex OI were recruited to the study. The study was set-up to explore whether there was a genetic link between bone fragility and autism in a sub-set of patients with bone fragility identified with autism traits in our complex/severe OI clinic. This was not set-up as a prevalence study but rather an exploration of genetics in association with ADI/ADOS confirmed ASD and bone fragility. ADI& ADOS: Standardised tools were used to confirm autism diagnosis. ADI and ADOS were completed by the Clinical Psychologist; ADI comprises a 93 item semi-structured clinical review with a diagnostic algorithm diagnosing Autism; ADOS is a semi-structured assessment of socialisation, communication and play/imagination which also provides a diagnostic algorithm. EXOME SEQUENCING: In patients recruited, those that fulfilled research criteria for diagnosis of autism using above tools were recruited to trio whole exome sequencing (WES). RESULTS: one patient had compound heterozygous variants in NBAS; one patient had a variant in NRX1; one patient had a maternally inherited PLS3 variant; all the other patients in this cohort had pathogenic variants in COL1A1/COL1A2. CONCLUSIONS: Although, not set out as an objective, we were able to establish that identifying autism had important clinical and social benefits for patients and their families in ensuring access to services, appropriate schooling, increased understanding of behaviour and support. LAY SUMMARY: It is important for clinicians looking after children with brittle bone disease, also referred to as Osteogenesis Imperfecta (OI) to be aware of early features of developmental delay/autistic traits especially with severe forms of OI as the emphasis is on their mobility and bone health. Ensuring appropriate assessment and access to services early-on will enable these patients to achieve their potential. Further investigations of genomics in bone fragility in relation to autism are required and dual diagnosis is essential for high quality clinical and educational provision.

11.
Nat Biotechnol ; 22(1): 53-4, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14661028

RESUMO

We have observed karyotypic changes involving the gain of chromosome 17q in three independent human embryonic stem (hES) cell lines on five independent occasions. A gain of chromosome 12 was seen occasionally. This implies that increased dosage of chromosome 17q and 12 gene(s) provides a selective advantage for the propagation of undifferentiated hES cells. These observations are instructive for the future application of hES cells in transplantation therapies in which the use of aneuploid cells could be detrimental.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 12 , Cromossomos Humanos Par 17 , Embrião de Mamíferos/citologia , Células-Tronco/citologia , Aneuploidia , Animais , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Células Cultivadas , Bandeamento Cromossômico , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Modelos Genéticos , Manejo de Espécimes , Fatores de Tempo
12.
Clin Dysmorphol ; 25(1): 19-22, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26287558

RESUMO

Duplications of 18p have been reported in the literature associated with a range of different abnormalities and also in patients with normal phenotypes. The majority of these reports are based solely on G-banded cytogenetic evaluation. The use of arrayCGH characterization has improved the ability to define regions of imbalance and is helping to identify potential underlying triplosufficiency of any duplicated genes. We report on a family where the father and his two daughters all have a duplication 18p11.32-p11.31 characterized by microarray. They present with variable levels of intellectual disability/developmental delay and behavioural difficulties without any physical anomalies. This family contributes toward the growing knowledge of pure duplications of 18p and provides information on interpretation of novel array findings in the context of family history. It also reiterates the importance of elucidating a detailed learning and developmental phenotype and family pedigree in aiding interpretation of genetic testing results.


Assuntos
Duplicação Cromossômica , Cromossomos Humanos Par 18 , Deficiências do Desenvolvimento/genética , Deficiência Intelectual/genética , Adulto , Transtorno Autístico/genética , Criança , Duplicação Cromossômica/genética , Cromossomos Humanos Par 18/genética , Hibridização Genômica Comparativa , Feminino , Duplicação Gênica , Estudos de Associação Genética , Humanos , Hibridização in Situ Fluorescente , Masculino , Linhagem
13.
Cloning Stem Cells ; 5(4): 339-54, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14733752

RESUMO

Somatic cell reprogramming holds great promise for the development of novel cellular therapeutics. A number of sources of reprogramming potential have been identified, including oocytes, embryonic germ (EG) cells and embryonic stem (ES) cells. However, each of these sources of reprogramming factors is problematic, since they are either not freely available or have special growth requirements. Embryonal carcinoma (EC) cells are another source of pluripotent cells that, unlike ES and EG cells, do not usually require special growth conditions. Since they share many of the key characteristics of ES cells, such as pluripotency, EC cells may provide a readily amenable alternative source of reprogramming factors and could serve as a model for ES cells in this respect. Here we show that mouse EC cells can also function as donors of reprogramming factors. PEG-mediated fusion between murine EC cells (P19) and the cells of a human T-lymphoma cell line (CEM-GFP) resulted in inter-species hybrid colony formation. Colonies of hybrid cells displayed heterogeneity in cellular morphology as well as in their pattern of human gene expression. Expression of two human transcription factors characteristic of undifferentiated pluripotent stem cells, Oct-4 and Sox-2, was detected in the hybrid cells, demonstrating activation of endogenous human markers of pluripotency. Simultaneously, down-regulation of CD45, a marker present in lymphocytic cells, was observed in some hybrids. The detection of human specific markers of differentiation, such as nestin, lamininbeta1, and collagen IValpha1, indicates that fusion resulted in reprogramming of the human cells to reflect the differentiation potential of the murine EC partner.


Assuntos
Biomarcadores/análise , Carcinoma Embrionário/metabolismo , Diferenciação Celular/fisiologia , Células Híbridas/metabolismo , Neoplasias Embrionárias de Células Germinativas/metabolismo , Células-Tronco Pluripotentes/metabolismo , Animais , Fusão Celular , Linhagem da Célula/fisiologia , Regulação da Expressão Gênica , Humanos , Cariotipagem
14.
Br J Ophthalmol ; 97(1): 40-6, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23137666

RESUMO

BACKGROUND: Even in experienced hands, the classification of some melanocytic lesions of the conjunctiva remains challenging. In skin pathology, the recent application of fluorescence in situ hybridisation (FISH) has been demonstrated to be of use for the analysis and diagnosis of ambiguous melanocytic neoplasms of the skin. This study set out to evaluate this method on seven prospective conjunctival cases that were histologically equivocal. METHODS: 18 unequivocal retrospective melanocytic controls were exposed to FISH. Commercially available probes assessing copy numbers of RREB1 (6p25), MYB (6q23) and CCND1 (11q13) genes compared with CEP6 (a chromosome six centromeric reference point) were used. After control verification, seven prospective, equivocal cases were identified and exposed to FISH. RESULTS: There was complete correlation between FISH result and the control section histopathology report. Control cases of melanoma cases were all positive for FISH and control benign lesions were negative. Of the seven equivocal cases, five were positive and classed as invasive melanoma or melanoma-in situ, one was negative and one tetraploid, classed as negative (these last two cases were classed as naevi with careful clinical observation). CONCLUSIONS: FISH is very useful in classifying equivocal conjunctival melanocytic lesions, especially those with atypical junctional activity and naevoid melanocytic proliferations of the conjunctiva.


Assuntos
Neoplasias da Túnica Conjuntiva/diagnóstico , Hibridização in Situ Fluorescente , Melanoma/diagnóstico , Nevo Pigmentado/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Túnica Conjuntiva/classificação , Neoplasias da Túnica Conjuntiva/genética , Ciclina D1/genética , Sondas de DNA , Proteínas de Ligação a DNA/genética , Feminino , Humanos , Masculino , Melanoma/classificação , Melanoma/genética , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Nevo Pigmentado/classificação , Nevo Pigmentado/genética , Estudos Prospectivos , Proteínas Proto-Oncogênicas c-myb/genética , Estudos Retrospectivos , Fatores de Transcrição/genética , Adulto Jovem
16.
J Pediatr Genet ; 1(4): 247-52, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27625832

RESUMO

Sub-telomeric deletions of the short arm of chromosome 6 are a well-described clinical entity characterized by developmental impairment, hypotonia, eye abnormalities and defects in the heart and kidneys. Chromosome 5p terminal duplication is a rarer entity, associated with developmental impairment and facial dysmorphism. We report a 3-year-old patient with a chromosome 6p25.1pter deletion and chromosome 5p15.1pter duplication who had global developmental impairment and unusual cerebral white matter changes, with hypoplastic corpus callosum and cerebellar vermis on magnetic resonance imaging -brain scan. We discuss the differential diagnosis to consider in patients with this appearance on magnetic resonance imaging -brain scan and reiterate the need for chromosome analysis in patients with this pattern of developmental anomaly. Tigroid pattern of cerebral white matter involvement has not been reported in chromosomal deletion/duplication syndromes. With the increasing use of molecular karyotyping for patients with multiple congenital anomalies and developmental delay, it is important to consider the exact size and nature of chromosomal deletion/duplication, in order to provide families with prognostic information and recurrence risk. This in turn, will help provide valuable information regarding the natural history of rare chromosomal imbalances.

18.
Exp Eye Res ; 83(3): 554-9, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16684523

RESUMO

Uveal melanomas are the commonest ocular tumour of adults and are characterized by reproducible alterations of chromosomes 1, 3, 6 and 8. These alterations are of prognostic relevance and have also be shown to correlate to high risk and low risk metastatic categories of uveal melanoma as defined by micro-array analysis. It is, however, possible that a catalogue of relevant genetic alterations, involving gene rearrangement rather than amplification, have as yet eluded identification. To address this point we examined 14 primary uveal melanomas, using 24 colour multiplex fluorescence in situ hybridization (M-FISH). All tumours were karyotyped following G-Banding, and M-FISH was performed to confirm and clarify the identity of abnormal chromosomes. M-FISH data were obtained from all tumours and was able to establish the nature of most abnormalities not fully characterized by cytogenetics. Abnormalities of chromosome 6 were far more frequent than previously indicated, in approximately 70% of cases, indicating they have been substantially underrepresented in past studies of uveal melanoma. Spindle melanomas were found to have novel rearrangements affecting in particular chromosomes 6, 15 and 18, suggesting that juxtaposition of genes through translocational events may play a role in the development of some uveal melanomas. In conclusion, this study is the largest of primary uveal melanoma analysed by M-FISH and indicates that alterations of chromosome 6 have previously been underestimated. Furthermore spindle melanomas are prone to rearrangements affecting chromosomes 6, 15 and 18, which may relate to early changes in uveal melanoma development or associate with those melanomas of a more differentiated status.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 15 , Cromossomos Humanos Par 18 , Cromossomos Humanos Par 6 , Melanoma/genética , Neoplasias Uveais/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Análise Citogenética , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Neoplasias Uveais/patologia
19.
Environ Sci Technol ; 39(19): 7749-56, 2005 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-16245854

RESUMO

Power plant fly ash from two fuels, coal and a mixture of coal and shredded tires, were evaluated for trace metal solubility in simulated human lung and gut fluids (SLF and SGF, respectively) to estimate bioaccessibility. The proportion of bioaccessible to total metal ranged from zero (V) to 80% (Zn) for coal-derived ash in SLF and from 2 (Th) to 100% (Cu) for tire-derived fly ash in SGF. The tire-derived ash contained much more Zn. However, Zn ranked only 5th of the various toxic metals in SGF compared with international regulations for ingestion. On the basis of total concentrations, the metals closestto exceeding limits based on international regulations for inhalation were Cr, Pb, and Al. On dissolution in SLF, the most limiting metals were Pb, Cu, and Zn. For metals exposed to SGF there was no relative change in the top metal, Al, before and after dissolution but the second-ranked metal shifted from Pb to Ni. In most cases only a proportion of the total metal concentrations in either fly ash was soluble, and hence bioaccessible, in either biofluid. When considering the regulatory limits for inhalation of particulates, none of the metal concentrations measured were as hazardous as the fly ash particulates themselves. However, on the basis of the international ingestion regulations for Al, the maximum mass of fly ash that could be ingested is only 1 mg per day (10 mg based on bioaccessibility). It is possible that such a small mass could be consumed by exposed individuals or groups.


Assuntos
Poluentes Ocupacionais do Ar/análise , Líquidos Corporais/química , Carbono/análise , Metais Pesados/química , Exposição Ocupacional/normas , Poluentes Ocupacionais do Ar/normas , Cinza de Carvão , Humanos , Espectrometria de Massas , Metais Pesados/toxicidade , Exposição Ocupacional/legislação & jurisprudência , Saúde Ocupacional , Tamanho da Partícula , Material Particulado , Medição de Risco , Solubilidade , Espectrometria por Raios X
20.
Hum Mol Genet ; 14(21): 3129-40, 2005 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16159889

RESUMO

Human embryonic stem cell (HESC) lines vary in their characteristics and behaviour not only because they are derived from genetically outbred populations, but also because they may undergo progressive adaptation upon long-term culture in vitro. Such adaptation may reflect selection of variants with altered propensity for survival and retention of an undifferentiated phenotype. Elucidating the mechanisms involved will be important for understanding normal self-renewal and commitment to differentiation and for validating the safety of HESC-based therapy. We have investigated this process of adaptation at the cellular and molecular levels through a comparison of early passage (normal) and late passage (adapted) sublines of a single HESC line, H7. To account for spontaneous differentiation that occurs in HESC cultures, we sorted cells for SSEA3, which marks undifferentiated HESC. We show that the gene expression programmes of the adapted cells partially reflected their aberrant karyotype, but also resulted from a failure in X-inactivation, emphasizing the importance in adaptation of karyotypically silent epigenetic changes. On the basis of growth potential, ability to re-initiate ES cultures and global transcription profiles, we propose a cellular differentiation hierarchy for maintenance cultures of HESC: normal SSEA3+ cells represent pluripotent stem cells. Normal SSEA3- cells have exited this compartment, but retain multilineage differentiation potential. However, adapted SSEA3+ and SSEA3- cells co-segregate within the stem cell territory, implying that adaptation reflects an alteration in the balance between self-renewal and differentiation. As this balance is also an essential feature of cancer, the mechanisms of culture adaptation may mirror those of oncogenesis and tumour progression.


Assuntos
Adaptação Fisiológica/fisiologia , Diferenciação Celular/fisiologia , Cromossomos Humanos/metabolismo , Embrião de Mamíferos/citologia , Epigênese Genética/genética , Regulação da Expressão Gênica no Desenvolvimento , Células-Tronco/citologia , Antígenos Glicosídicos Associados a Tumores , Diferenciação Celular/genética , Linhagem Celular , Cromossomos Humanos/genética , Primers do DNA , Citometria de Fluxo , Perfilação da Expressão Gênica , Glicoesfingolipídeos/metabolismo , Humanos , Microscopia de Fluorescência , Interferência de RNA , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Antígenos Embrionários Estágio-Específicos , Inativação do Cromossomo X/genética
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