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1.
Climacteric ; 26(5): 419-427, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37477236

RESUMO

A systematic review with meta-analysis was conducted to establish the impact of menopause health education on quality of life (QoL) among menopausal women. Research suggests that specific educational programs can support and enable women during the physical and emotional transition through menopause. The CINAHL, Medline, APA, Embase and Google Scholar databases were searched between 30 November 2021 and 9 January 2022 using the PRISMA guidelines. The Cochrane risk of bias tool was used to critically evaluate the included studies. Review Manager software was used to conduct the meta-analysis of suitable studies. Eight papers were eligible for this review. The participants were aged between 40 and 60 years, with diagnosis of menopause stemming from changes in the menstrual cycle to a last menstrual period of 7 years. Follow-up data were collected between 1 and 4 months post education. Meta-analysis of both the primary outcome (QoL) and secondary outcome (symptom control) demonstrated statistically significant improvements post intervention. Papers not suitable for meta-analysis were reviewed narratively; two papers assessing the primary outcome (QoL) demonstrated an improvement, but only one to a statistically significant level. Secondary outcomes revealed improvements, with all bar one paper doing so to statistical significance. Menopause health education demonstrated an improvement in both QoL and symptom control in menopausal women; however, given some weaknesses in the included studies, further research is justified. Limitations include participants' level of education, geographical location, risk of bias, that only half of the papers addressed participant use of hormone replacement therapy and length of follow-up.


Assuntos
Menopausa , Qualidade de Vida , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Menopausa/psicologia , Terapia de Reposição Hormonal
2.
Phys Rev Lett ; 128(7): 077402, 2022 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-35244442

RESUMO

ß-Ga_{2}O_{3} is an ultrawide band gap semiconductor with emerging applications in power electronics. The introduction of acceptor dopants yields semi-insulating substrates necessary for thin-film devices. In the present work, exposure of Cu-doped ß-Ga_{2}O_{3} to UV light >4 eV is shown to cause large, persistent photo-induced darkening at room temperature. Electron paramagnetic resonance spectroscopy indicates that light exposure converts Cu^{2+} to Cu^{3+}, a rare oxidation state that is responsible for the optical absorption. The photodarkening is accompanied by the appearance of O─H vibrational modes in the infrared spectrum. Hybrid function calculations show that Cu acceptors can favorably complex with hydrogen donors incorporated as interstitial (H_{i}) or substitutional (H_{O}) defects. When Cu_{Ga}-H_{O} complexes absorb light, hydrogen is released, contributing to the observed Cu^{3+} species and O─H modes.

3.
J Thromb Thrombolysis ; 50(2): 287-291, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32445064

RESUMO

Patients with COVID-19 have a coagulopathy and high thrombotic risk. In a cohort of 69 intensive care unit (ICU) patients we investigated for evidence of heparin resistance in those that have received therapeutic anticoagulation. 15 of the patients have received therapeutic anticoagulation with either unfractionated heparin (UFH) or low molecular weight heparin (LMWH), of which full information was available on 14 patients. Heparin resistance to UFH was documented in 8/10 (80%) patients and sub-optimal peak anti-Xa following therapeutic LMWH in 5/5 (100%) patients where this was measured (some patients received both anticoagulants sequentially). Spiking plasma from 12 COVID-19 ICU patient samples demonstrated decreased in-vitro recovery of anti-Xa compared to normal pooled plasma. In conclusion, we have found evidence of heparin resistance in critically unwell COVID-19 patients. Further studies investigating this are required to determine the optimal thromboprophylaxis in COVID-19 and management of thrombotic episodes.


Assuntos
Anticoagulantes/uso terapêutico , Betacoronavirus/patogenicidade , Coagulação Sanguínea/efeitos dos fármacos , Infecções por Coronavirus/terapia , Resistência a Medicamentos , Heparina/uso terapêutico , Unidades de Terapia Intensiva , Pneumonia Viral/terapia , Trombose/tratamento farmacológico , Adulto , Idoso , Anticoagulantes/efeitos adversos , Testes de Coagulação Sanguínea , COVID-19 , Infecções por Coronavirus/sangue , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/virologia , Monitoramento de Medicamentos , Feminino , Heparina/efeitos adversos , Interações Hospedeiro-Patógeno , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/sangue , Pneumonia Viral/diagnóstico , Pneumonia Viral/virologia , Estudos Retrospectivos , SARS-CoV-2 , Trombose/sangue , Trombose/diagnóstico , Trombose/virologia , Resultado do Tratamento
4.
J Thromb Thrombolysis ; 50(2): 478, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32572676

RESUMO

In the original publication of this article, one of the co-author name "D. de Monteverde-Robb" was inadvertently mentioned as "R. de Monteverde-Robb". The correct author name is "D. de Monteverde-Robb". This error has been corrected with this erratum.

5.
Phys Chem Chem Phys ; 17(44): 29541-7, 2015 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-26366854

RESUMO

Biological nitrogen fixation by nitrogenase enzymes is a process that activates dinitrogen (N2) one of the most inert molecules in nature, within the confines of a living organism and at ambient conditions. Despite decades of study, there are still no complete explanations as to how this is possible. Here we describe a model of N2 reduction using the Mo-containing nitrogenase (FeMoco) that can explain the reactivity of the active site via a series of electrochemical steps that reversibly unseal a highly reactive Fe edge site. Our model can explain the 8 proton-electron transfers involved in biological ammonia synthesis within the kinetic scheme of Lowe and Thorneley, the obligatory formation of one H2 per N2 reduced, and the behavior of known inhibitors.


Assuntos
Fixação de Nitrogênio , Nitrogenase/metabolismo
6.
Proc Natl Acad Sci U S A ; 107(19): 8513-8, 2010 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-20404195

RESUMO

Identifying and designing physical systems for use as qubits, the basic units of quantum information, are critical steps in the development of a quantum computer. Among the possibilities in the solid state, a defect in diamond known as the nitrogen-vacancy (NV(-1)) center stands out for its robustness--its quantum state can be initialized, manipulated, and measured with high fidelity at room temperature. Here we describe how to systematically identify other deep center defects with similar quantum-mechanical properties. We present a list of physical criteria that these centers and their hosts should meet and explain how these requirements can be used in conjunction with electronic structure theory to intelligently sort through candidate defect systems. To illustrate these points in detail, we compare electronic structure calculations of the NV(-1) center in diamond with those of several deep centers in 4H silicon carbide (SiC). We then discuss the proposed criteria for similar defects in other tetrahedrally coordinated semiconductors.

7.
Epilepsy Behav ; 20(2): 299-307, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21195671

RESUMO

Opportunities exist to significantly improve the quality and efficiency of epilepsy care in Ireland. Historically, epilepsy research has focused on quantitative methodologies that often fail to capture the invaluable insight of patient experiences as they negotiate their health care needs. Using a phenomenological approach, we conducted one-to-one interviews with people with epilepsy, reporting on their understanding of their health care journey from onset of symptoms through to their first interaction with specialist epilepsy services. Following analysis of the data, five major themes emerged: delayed access to specialist epilepsy review; uncertainty regarding the competency and function of primary care services; significant unmet needs for female patients with epilepsy; disorganization of existing epilepsy services; and unmet patient information needs. The findings reveal important insights into the challenges experienced by people with epilepsy in Ireland and identify the opportunities for future service reorganization to improve the quality and efficiency of care provided.


Assuntos
Atenção à Saúde/métodos , Epilepsia/terapia , Necessidades e Demandas de Serviços de Saúde/estatística & dados numéricos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Epilepsia/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Entrevistas como Assunto , Irlanda/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
8.
Ir Med J ; 104(7): 214-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21957690

RESUMO

Effective chronic disease management (CDM) requires the ready availability and communication of accurate, clinical disease specific information. Using epilepsy as a probe into CDM, we report on the availability and reliability of clinical information in the primary care records of people with epilepsy (PWE). The medical records of 374 PWE from 53 general practices in the Mid-West region of Ireland were examined. Confirmation of an epilepsy diagnosis by a neurologist was documented for 132 (35%) patients. 282 (75%) patients had no documented evidence of receiving specialist neurology review while 149 (40%) had not been reviewed by their GP in the previous two years for their epilepsy. Significant variation in documentation of epilepsy specific information together with an inadequacy and inconsistency of existing epilepsy services was highlighted.


Assuntos
Prestação Integrada de Cuidados de Saúde/organização & administração , Gerenciamento Clínico , Epilepsia/terapia , Documentação , Humanos , Irlanda , Auditoria Médica , Atenção Primária à Saúde
9.
Science ; 242(4876): 263-6, 1988 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-3175651

RESUMO

Structural changes of the human retinoblastoma gene have been demonstrated previously in retinoblastoma and some clinically related tumors including osteosarcoma. Structural aberrations of the retinoblastoma locus (RB1) were observed in 25% of breast tumor cell lines studied and 7% of the primary tumors. These changes include homozygous internal deletions and total deletion of RB1; a duplication of an exon was observed in one of the cell lines. In all cases, structural changes either resulted in the absence or truncation of the RB1 transcript. No obvious defect in RB1 was detected by DNA blot analysis in primary tumors or cell lines from Wilms' tumor, cervical carcinoma, or hepatoma. These results further support the concept that the human RB1 gene has pleiotropic effects on specific types of cancer.


Assuntos
Neoplasias da Mama/genética , Neoplasias Oculares/genética , Rearranjo Gênico , Retinoblastoma/genética , Aberrações Cromossômicas , Cromossomos Humanos Par 13 , DNA/genética , Sondas de DNA , Éxons , Feminino , Homozigoto , Humanos , Metástase Linfática , Menopausa , Mutação , Hibridização de Ácido Nucleico , Fatores de Risco , Células Tumorais Cultivadas
10.
Science ; 286(5449): 2528-31, 1999 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-10617473

RESUMO

The hCHK2 gene encodes the human homolog of the yeast Cds1 and Rad53 G2 checkpoint kinases, whose activation in response to DNA damage prevents cellular entry into mitosis. Here, it is shown that heterozygous germ line mutations in hCHK2 occur in Li-Fraumeni syndrome, a highly penetrant familial cancer phenotype usually associated with inherited mutations in the TP53 gene. These observations suggest that hCHK2 is a tumor suppressor gene conferring predisposition to sarcoma, breast cancer, and brain tumors, and they also provide a link between the central role of p53 inactivation in human cancer and the well-defined G2 checkpoint in yeast.


Assuntos
Fase G2 , Genes Supressores de Tumor , Mutação em Linhagem Germinativa , Síndrome de Li-Fraumeni/genética , Proteínas Serina-Treonina Quinases/genética , Alelos , Apoptose , Neoplasias Encefálicas/genética , Neoplasias da Mama/genética , Quinase 1 do Ponto de Checagem , Quinase do Ponto de Checagem 2 , Feminino , Fase G1 , Genes p53 , Predisposição Genética para Doença , Heterozigoto , Humanos , Síndrome de Li-Fraumeni/enzimologia , Síndrome de Li-Fraumeni/patologia , Masculino , Linhagem , Polimorfismo Genético , Proteínas Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Sarcoma/genética , Transdução de Sinais , Células Tumorais Cultivadas
11.
Ir Med J ; 102(6): 173-6, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19722352

RESUMO

Epilepsy care in Ireland is shared between primary, secondary and tertiary care services with the General Practitioner (GP) managing the process. Barriers to effective epilepsy care in Irish general practice remain undocumented although sub-optimal and fragmented services are frequently anecdotally reported. This survey of Irish GPs reports on such barriers to epilepsy care and on the Information & Communication Technology (ICT) issues potentially relevant to the use of an epilepsy specific Electronic Patient Record (EPR). The response rate was 247/700 (35.3%). Respondents supported the concept of shared care for epilepsy 237 (96%) however they were very dissatisfied with existing neurology services, including pathways of referral 207 (84%) and access to specialist neurology advice and investigations 232 (94%). They reported that neurology services and investigations may be accessed more expeditiously by patients with private health insurance than those without 178 (72%). Consequently many patients are referred to the emergency department for assessment and treatment 180 (73%). A deficit in epilepsy care expertise among GPs was acknowledged 86 (35%). While computerisation of GP practices appears widespread 230 (93%), just over half the respondents utilise available electronic functionalities specific to chronic disease management. GP specific electronic systems infrequently link or communicate with external electronic sources 133 (54%). While the current pathways of care for epilepsy in Ireland appear fragmented and inadequate, further investigations to determine the quality and cost effectiveness of the current service are required.


Assuntos
Atenção à Saúde/organização & administração , Epilepsia/tratamento farmacológico , Médicos de Família , Padrões de Prática Médica/estatística & dados numéricos , Atenção Primária à Saúde/estatística & dados numéricos , Adulto , Continuidade da Assistência ao Paciente , Atenção à Saúde/tendências , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Irlanda , Masculino , Pessoa de Meia-Idade , Neurologia/estatística & dados numéricos , Encaminhamento e Consulta , Inquéritos e Questionários
12.
J Clin Invest ; 79(3): 978-83, 1987 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3469218

RESUMO

Prostaglandin (PG) D2, the predominant prostanoid released from activated mast cells in humans is initially metabolized by reduction of the C-11 keto function to yield 9 alpha,11 beta-PGF2. In this study the airways effects of 9 alpha,11 beta-PGF2 were compared with those of its epimer 9 alpha,11 alpha-PGF2 (PGF2 alpha) and PGD2. 9 alpha,11 beta-PGF2 was a potent contractile agonist of isolated guinea pig trachea and 4-mm human airways in vitro; the potencies of the PGs relative to PGD2 (= 1.00) being 0.65 (NS) and 4.08 (P less than 0.001) for 9 alpha,11 beta-PGF2, and 0.52 (P less than 0.01) and 2.40 (P less than 0.001) for PGF2 alpha, respectively. When inhaled by asthmatic subjects, 9 alpha,11 beta-PGF2 was a potent bronchoconstrictor agent, being approximately equipotent with PGD2 and 28-32 times more potent than histamine (P less than 0.01). These studies suggest that 9 alpha,11 beta-PGF2 is at least equipotent with PGD2 as a bronchoconstrictor agonist, and in being a major metabolite of PGD2, could contribute to the bronchoconstrictor effect of this mast cell-derived mediator in asthma.


Assuntos
Brônquios/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Prostaglandinas F/farmacologia , Traqueia/efeitos dos fármacos , Adulto , Resistência das Vias Respiratórias/efeitos dos fármacos , Animais , Asma/fisiopatologia , Brônquios/fisiopatologia , Dinoprosta , Volume Expiratório Forçado , Cobaias , Histamina/farmacologia , Humanos , Medidas de Volume Pulmonar , Masculino , Prostaglandina D2 , Prostaglandinas D/farmacologia , Traqueia/fisiologia
13.
Cancer Res ; 57(15): 3245-52, 1997 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-9242456

RESUMO

We have previously reported on the analysis of TP53 coding mutations in 12 classic Li-Fraumeni syndrome (LFS) families plus 9 families that were Li-Fraumeni-like (LFL) families (J. M. Birch et al., Cancer Res., 54: 1298-1304, 1994). Mutations were found in 6 of 12 LFS families and in 1 of 9 LFL families. We have now extended these studies to include an additional nine LFS and nine LFL families, and TP53 mutations have been detected in eight of nine LFS families and in three of nine LFL families. Six of the new mutations described here are the same as those previously identified in other Li-Fraumeni families and are missense mutations at codons 245, 248, and 273 (in two families); a nonsense mutation at codon 209; and a mutation at the splice donor site in exon 4. The other five mutations are novel germ-line mutations and include missense mutations at codons 136 and 344, a 2-bp deletion within codon 191, a splice acceptor mutation in intron 3, and a 167-bp deletion of part of exon 1 and intron 1. In addition, we have detected a codon 175 mutation in a family previously reported as TP53 negative. To summarize all of the data from the families we have studied in this and our previous report (J. M. Birch et al., Cancer Res., 54: 1298-1304, 1994), mutations have been detected in 15 of 21 LFS families (71%) and in 4 of 18 LFL families (22%). These figures are somewhat higher than those previously reported by us and others for the frequency of TP53 mutations in LFS and LFL families. This could reflect our analysis of all 11 exons of TP53, including noncoding regions, as well as the use of direct sequencing rather than other less-sensitive mutation detection methods.


Assuntos
Genes p53/genética , Mutação em Linhagem Germinativa/genética , Síndrome de Li-Fraumeni/genética , Feminino , Ligação Genética , Humanos , Masculino , Mutação , Regiões Promotoras Genéticas/genética
14.
Cancer Res ; 61(22): 8062-7, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11719428

RESUMO

Li Fraumeni Syndrome (LFS) is a multicancer phenotype, most commonly associated with germ-line mutations in TP53. In a kindred with LFS without an inherited TP53 mutation, we have previously reported a truncating mutation (1100delC) in CHK2, encoding a kinase that phosphorylates p53 on Ser(20). Here, we describe a CHK2 missense mutation (R145W) in another LFS family. This mutation destabilizes the encoded protein, reducing its half-life from >120 min to 30 min. This effect is abrogated by treatment of cells with a proteosome inhibitor, suggesting that CHK2(R145W) is targeted through this degradation pathway. Both 1100delC and R145W germ-line mutations in CHK2 are associated with loss of the wild-type allele in the corresponding tumor specimens, and neither tumor harbors a somatic TP53 mutation. Our observations support the functional significance of CHK2 mutations in rare cases of LFS and suggest that such mutations may substitute for inactivation of TP53.


Assuntos
Síndrome de Li-Fraumeni/genética , Mutação de Sentido Incorreto , Proteínas Quinases/genética , Proteínas Serina-Treonina Quinases , Adulto , Sequência de Bases , Quinase do Ponto de Checagem 2 , Neoplasias do Colo/genética , DNA Complementar/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Genes p53/genética , Humanos , Síndrome de Li-Fraumeni/enzimologia , Perda de Heterozigosidade , Masculino , Dados de Sequência Molecular , Linhagem , Proteínas Quinases/metabolismo , Células Tumorais Cultivadas
15.
Oncogene ; 17(26): 3513-9, 1998 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-10030676

RESUMO

We have identified a region of chromosome 1p31.1 that shows high frequency loss of heterozygosity (LOH) in human breast cancer. This region forms part of a 7 Mb YAC/BAC contig. In order to identify candidate sequences, mutation of which might contribute to the development of disease, we have carried out mapping studies of ESTs localized to 1p31.1. This analysis, coupled with library screening and a modified 5' RACE-PCR strategy, resulted in the identification and characterization of a novel gene (LPHH1) which is located adjacent to the smallest region of overlapping loss (SRO) seen in tumours. The 4209 bp open reading frame of the 7 kb LPHH1 transcript encodes a peptide which shows approximately 65% identity to rat latrophilin, a G-coupled, seven span transmembrane protein, which binds alpha-latrotoxin. In the human sequence, whilst conservation of the transmembrane domain is high, the intra- and extracellular domains show two regions of variable structure, which are presumably generated by alternative splicing. Surprisingly, while expression of the rat gene is tightly restricted to neurological and perhaps some endocrine cells, the human sequence appears to be expressed very widely in all normal tissues tested. Northern and RT-PCR analysis of a panel of tumour cell lines showed that LPHH1 expression was variable, apparently elevated in some lines and absent or markedly reduced in others. Furthermore, characterization of the range of transcripts encoded in a breast tumour cell line, compared to normal breast, suggested that gene product variability was higher in the tumour.


Assuntos
Neoplasias da Mama/genética , Proteínas de Membrana/genética , Receptores de Peptídeos/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/isolamento & purificação , Regulação Neoplásica da Expressão Gênica , Humanos , Dados de Sequência Molecular , Ratos , Receptores Acoplados a Proteínas G , Valores de Referência , Análise de Sequência , Células Tumorais Cultivadas
16.
Oncogene ; 14(9): 1059-65, 1997 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-9070654

RESUMO

Comparative genomic hybridisation has been used to map copy number changes in nine cases of ductal carcinoma in situ of the breast obtained from wax-embedded archive material. A wide variety of abnormalities were detected including gain of regions of 1q, 17q, 19q, 20p and 20q and loss on 13q, 14q, 17p, 16q and 22q. Amplification of areas on 10p, 8q and 20q were also observed. Chromosomal alterations were more frequent in higher grade DCIS and closely resemble those previously detected in invasive breast cancer using the same technique. These data provide strong molecular support for the view that DCIS is a precursor lesion of invasive breast carcinoma.


Assuntos
Neoplasias da Mama/genética , Carcinoma in Situ/genética , Carcinoma Ductal de Mama/genética , Amplificação de Genes/genética , Deleção de Genes , Idoso , Feminino , Humanos , Técnicas In Vitro , Pessoa de Meia-Idade , Hibridização de Ácido Nucleico/métodos , Estudos Retrospectivos
17.
Oncogene ; 1(4): 431-8, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-2838785

RESUMO

We have identified a rearranged c-myc gene in DNA from tumour tissue from a patient with an aggressive carcinoma of the breast. Analysis of this rearranged gene isolated from a size-fractionated genomic library revealed that a deletion had occurred within exon 3. This deletion, of approximately 5 kb, interrupts the coding region of exon 3, and would result in a truncated myc protein with an altered C-terminus. Sequence analysis of the rearranged c-myc gene and the sequence downstream of c-myc which is involved in the deletion has shown precisely where the breakpoint has occurred in both sequences and reveals a short region of homology which could perhaps permit illegitimate recombination between the two sequences.


Assuntos
Neoplasias da Mama/genética , Carcinoma/genética , Proteínas Proto-Oncogênicas/genética , Proto-Oncogenes , Sequência de Bases , Deleção Cromossômica , Enzimas de Restrição do DNA/metabolismo , Humanos , Dados de Sequência Molecular , Recombinação Genética
18.
Oncogene ; 10(8): 1653-7, 1995 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-7731721

RESUMO

Ductal carcinoma in situ (DCIS) of the breast is commonly described as a premalignant lesion. Using PCR to amplify DNA from areas of tumour cells which have been microdissected from fixed material, we have studied the involvement of chromosome 1 in 19 cases of DCIS. A series of microsatellite repeat polymorphisms has been used to define regions of allelic imbalance and this has confirmed the involvement in DCIS of six of the regions previously implicated in studies of invasive breast tumours. This suggests that these regions may harbour tumour suppressor genes, the inactivation of which is important for the early stages of breast tumour development. Analysis of separate ducts from within the same tumour has revealed that the same genetic alterations are not necessarily present throughout the lesion. In addition we have found that in three cases where frank invasive carcinoma is also present, similar alterations can be detected in the in situ and invasive component.


Assuntos
Neoplasias da Mama/genética , Carcinoma in Situ/genética , Carcinoma Ductal de Mama/genética , Aberrações Cromossômicas , Cromossomos Humanos Par 1 , Feminino , Genes Supressores de Tumor , Humanos
19.
Oncogene ; 1(4): 423-30, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3330785

RESUMO

We have examined the genomic organisation of c-myc, N-myc, L-myc, neu and N-ras in tissue from 41 breast carcinomas, lymph node metastases from 10 of these carcinomas, one fibrosarcoma, 10 cases of benign fibrocystic breast and six fibroadenomas. We have not observed an alteration in either N-myc or N-ras in any of the samples studied. We have seen a 2-fold amplification of L=myc in DNA from one infiltrating ductal (ID) carcinoma, but otherwise we have seen no alterations to this gene. Amplification of c-myc was seen in 22% of ID breast carcinoma sample. Levels of amplification ranged from 2- to 10-fold. We have found a significant (p less than 0.02) correlation between an altered c-myc gene and a very poor short-term prognosis. Amplification of neu was seen in 19% of ID breast carcinomas, but the levels of amplification were higher than those seen for c-myc. Alterations to neu also correlated well with poor short-term prognosis (p less than 0.0002). Finally, we have observed a low level of amplification of c-myc in DNA from a benign fibrocystic breast lesion. This lesion exhibited some features characteristic of those thought to be associated with an increased risk of developing breast cancer.


Assuntos
Neoplasias da Mama/genética , Carcinoma/genética , DNA de Neoplasias/genética , Doença da Mama Fibrocística/genética , Proteínas Proto-Oncogênicas/genética , Proto-Oncogenes , Amplificação de Genes , Genes , Humanos , Metástase Linfática , Prognóstico
20.
Oncogene ; 14(15): 1869-74, 1997 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-9150393

RESUMO

Previous investigations of a Li - Fraumeni like family (Barnes et al., 1992) demonstrated that both the proband and her mother had elevated p53 protein levels in both tumour tissue and normal tissue at sites distant from the tumour, although no mutation was found in the p53 gene. In the present study two recently described functional assays for p53, an apoptotic assay and the functional assay for the separation of alleles in yeast (FASAY), have been employed to study the functional activity of p53 from this patient. The results of the apoptotic assay demonstrated that this patient had a p53 functional defect and the FASAY result suggested that this defect was in fact a germline mutation of the p53 gene. A point mutation of codon 337, which results in an amino acid substitution of a cysteine for an arginine, was demonstrated initially in cDNA and was confirmed by sequencing of genomic DNA. This is an unusual mutation as it is in the oligomerisation domain of p53, in contrast to the majority of p53 mutations which are in the core DNA binding domain. This mutation results in a protein which still retains partial transactivational activity in the FASAY. The mutation of codon 337 is only the second reported case of a germline missense mutation occurring in the oligomerisation domain of p53.


Assuntos
Genes p53 , Mutação em Linhagem Germinativa , Síndrome de Li-Fraumeni/genética , Mutação Puntual , Proteína Supressora de Tumor p53/genética , Alelos , Apoptose/fisiologia , Códon , DNA Complementar/sangue , DNA Complementar/genética , Humanos , Síndrome de Li-Fraumeni/sangue , Síndrome de Li-Fraumeni/patologia , Linfócitos/fisiologia , Estrutura Terciária de Proteína , Transformação Genética , Proteína Supressora de Tumor p53/fisiologia
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