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1.
BMC Cancer ; 20(1): 1000, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33059604

RESUMO

BACKGROUND: MCM5 is a protein involved in DNA replication, facilitating cell proliferation. In normal epithelium MCM5 expression is restricted to the cells in the basal proliferative compartments, however in the presence of a tumour MCM5 positive cells are present at the surface epithelium and are shed into bodily fluids. The aim of this study was to determine the sensitivity of MCM5 as a biomarker for the detection of endometrial and ovarian cancer. METHODS: Patients with known ovarian or endometrial cancers, or known benign gynaecological conditions, were enrolled. Informed consent was obtained prior to the collection of full void urine, and either a vaginal tampon (worn for 6-8 h), or a vaginal swab. Vaginal secretions were extracted from the tampon or swab, centrifuged and lysed. Urine samples were centrifuged and lysed. MCM5 levels were determined by MCM5-ELISA (Arquer Diagnostics Ltd). RESULTS: 125 patients completed the study protocol, 41 patients had endometrial cancer, 26 ovarian cancer, and 58 benign controls. All patients provided a urine sample and either a tampon or vaginal swab sample. Urine MCM5 levels were higher in cancer patients than controls (p < 0.0001), there was no significant difference in levels between tampon samples or vaginal swab samples in cancer patients when compared to controls. Performance of MCM5 to discriminate cancer from benign disease was high with an area under the ROC curve of 0.83 for endometrial cancer and 0.68 for ovarian cancer. Using a cut off of 12 pg/mL, overall sensitivity for endometrial cancer was 87.8, and 61.5% for ovarian cancer with a specificity of 75.9%. CONCLUSIONS: MCM5 is a novel sensitive and specific biomarker for the detection of ovarian and endometrial tumours in urine samples, which is likely to have clinical utility as a diagnostic aid.


Assuntos
Biomarcadores Tumorais/metabolismo , Proteínas de Ciclo Celular/metabolismo , Neoplasias do Endométrio/diagnóstico , Neoplasias Ovarianas/diagnóstico , Idoso , Detecção Precoce de Câncer , Feminino , Humanos , Pessoa de Meia-Idade
2.
Exp Neurol ; 260: 50-5, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24800913

RESUMO

Oligodendrocyte progenitors (OPs) are a major proliferating cell population within the adult CNS. In response to myelin loss or increasing demand, OPs have the capacity to differentiate into mature, myelinating oligodendrocytes. The name 'oligodendrocyte progenitor' suggests restriction to the oligodendrocyte cell lineage. However, with growing evidence of the lineage plasticity of OPs both in vitro and in vivo, we discuss whether they have potential beyond that expected of dedicated progenitor cells, and hence may justify categorization as adult stem cells.


Assuntos
Sistema Nervoso Central/citologia , Oligodendroglia/citologia , Células-Tronco/citologia , Células-Tronco Adultas/citologia , Animais , Diferenciação Celular/fisiologia , Sistema Nervoso Central/metabolismo , Humanos , Oligodendroglia/metabolismo , Células-Tronco/metabolismo
3.
J Thromb Haemost ; 12(5): 716-25, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24612435

RESUMO

BACKGROUND: The study of patients with bleeding problems is a powerful approach in determining the function and regulation of important proteins in human platelets. We have identified a patient with a chronic bleeding disorder expressing a homozygous P2RY(12) mutation, predicting an arginine to cysteine (R122C) substitution in the G-protein-coupled P2Y(12) receptor. This mutation is found within the DRY motif, which is a highly conserved region in G-protein-coupled receptors (GPCRs) that is speculated to play a critical role in regulating receptor conformational states. OBJECTIVES: To determine the functional consequences of the R122C substitution for P2Y(12) function. PATIENT/METHODS: We performed a detailed phenotypic analysis of an index case and affected family members. An analysis of the variant R122C P2Y(12) stably expressed in cells was also performed. RESULTS: ADP-stimulated platelet aggregation was reduced as a result of a significant impairment of P2Y(12) activity in the patient and family members. Cell surface R122C P2Y(12) expression was reduced both in cell lines and in platelets; in cell lines, this was as a consequence of agonist-independent internalization followed by subsequent receptor trafficking to lysosomes. Strikingly, members of this family also showed reduced thrombin-induced platelet activation, owing to an intronic polymorphism in the F2R gene, which encodes protease-activated receptor 1 (PAR-1), that has been shown to be associated with reduced PAR-1 receptor activity. CONCLUSIONS: Our study is the first to demonstrate a patient with deficits in two stimulatory GPCR pathways that regulate platelet activity, further indicating that bleeding disorders constitute a complex trait.


Assuntos
Plaquetas/citologia , Hemorragia/enzimologia , Mutação , Polimorfismo Genético , Receptor PAR-1/genética , Receptores Purinérgicos P2Y12/genética , Motivos de Aminoácidos , Linhagem Celular Tumoral , Doença Crônica , Feminino , Homozigoto , Humanos , Masculino , Fenótipo , Ativação Plaquetária/efeitos dos fármacos , Agregação Plaquetária/efeitos dos fármacos , Mutação Puntual , Conformação Proteica , Receptor PAR-1/fisiologia , Receptores Acoplados a Proteínas G/metabolismo , Análise de Sequência de DNA
4.
J Infect ; 65(5): 377-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22960369

RESUMO

November 18th 2012 is the fifth annual European Antibiotic Awareness Day (EAAD), an opportunity to raise public and professional awareness about the importance of prudent antibiotic use, and the threat of antibiotic resistance to public health. The aims of EAAD have been supported and reinforced by antibiotic stewardship campaigns across Europe, aimed at both healthcare professionals, and the public. Within the UK, antimicrobial stewardship is embedded within the Health and Social Care Act 2008, and is taken into account by the Care Quality Commission when making decisions about registration. The Department of Health Advisory Committee on Antimicrobial Resistance and Healthcare Associated Infection has recently produced guidance for antimicrobial stewardship in hospitals, 'Start Smart - then Focus', and the Royal College of General Practitioners has agreed antimicrobial stewardship as a clinical priority for 3 years, providing educational and audit materials, and tools to help general practitioners in patient consultations, to manage public demand for antibiotics when not clinically indicated. British Infection Association members need to be familiar with these initiatives and resources, and are encouraged to lead on local initiatives within their own workplaces and communities.


Assuntos
Antibacterianos/uso terapêutico , Educação em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Farmacorresistência Bacteriana , Europa (Continente) , Pessoal de Saúde , Humanos , Pacientes , Saúde Pública
7.
Eur Respir J ; 33(6): 1338-44, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19164359

RESUMO

The aim of the present study was to identify alpha(1)-antitrypsin (alpha(1)-AT)-deficient patients who had rapidly progressive disease. PiZ patients (n = 101) underwent annual lung function measurements over a 3-yr period, and the results were related to factors that may influence decline. The mean annual decline in forced expiratory volume in 1 s (FEV(1)) was 49.9 mL. The greatest FEV(1) decline occurred in the moderate severity group (FEV(1) 50-80% of the predicted value), with a mean annual decline of 90.1 mL, compared with 8.1 mL in the very severe group (FEV(1) <30% pred). However, annual decline in transfer coefficient of the lung for carbon monoxide (K(CO)) was greatest in the severe and very severe groups. When the whole group was divided into tertiles of FEV(1) decline, the fast tertile compared with the slow tertile had more patients with bronchodilator reversibility (BDR) (73 versus 41%; p = 0.010), more males (79 versus 56%; p = 0.048) and lower body mass index (BMI) (24.0 versus 26.1; p = 0.042). Logistic regression analyses confirmed that FEV(1) decline was independently associated with BMI, BDR, exacerbation rate and high physical component 36-item short-form health survey scores. In PiZ alpha(1)-AT-deficient patients, FEV(1) decline was greatest in moderate disease, unlike K(CO) decline, which was greatest in severe disease. The FEV(1) decline showed associations with BDR, BMI, sex and exacerbation rate.


Assuntos
Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Enfisema Pulmonar/fisiopatologia , Deficiência de alfa 1-Antitripsina/fisiopatologia , Broncodilatadores/uso terapêutico , Progressão da Doença , Feminino , Volume Expiratório Forçado , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Enfisema Pulmonar/diagnóstico por imagem , Enfisema Pulmonar/tratamento farmacológico , Sistema de Registros , Análise de Regressão , Testes de Função Respiratória , Fatores de Risco , Índice de Gravidade de Doença , Fumar , Estatísticas não Paramétricas , Inquéritos e Questionários , Tomografia Computadorizada por Raios X , Deficiência de alfa 1-Antitripsina/terapia
8.
Cell Mol Life Sci ; 65(20): 3265-89, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18695942

RESUMO

The identification of the aspartic protease BACE1 (beta-secretase) was a defining event in research aimed at understanding the molecular mechanisms that underlie Alzheimer's disease (AD) pathogenesis. This is because BACE1 catalyses the rate limiting step in the production of amyloid-beta (Abeta) the principal component of plaque pathology in AD, the excessive production of which is believed to be a primary cause of neurodegeneration, and cognitive dysfunction in AD. Subsequent discoveries showed that genetic deletion of BACE1 completely abolishes Abeta production and deposition in vivo, and that BACE1 activity is significantly increased in AD brain. In this review we present current knowledge on BACE1, discussing its structure, function and complex regulation with a view to understanding BACE1 function in the brain, and BACE1 as a target in blocking aberrant Abeta production in AD.


Assuntos
Doença de Alzheimer/enzimologia , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/biossíntese , Sequência de Aminoácidos , Secretases da Proteína Precursora do Amiloide/química , Secretases da Proteína Precursora do Amiloide/genética , Animais , Evolução Molecular , Humanos , Dados de Sequência Molecular , Processamento de Proteína Pós-Traducional , Especificidade por Substrato
9.
Endocr Relat Cancer ; 14(3): 613-24, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17914092

RESUMO

GnRH II has important functional effects in steroid hormone-dependent tumours. Here we investigated the expression and regulation of GnRH II in prostate cancer. GnRH II protein was equally expressed in benign (73%) and malignant (78%) biopsies studied in a prostate tissue microarray (P = 0.779). There was no relationship between expression and clinical parameters in the cancer cohort. GnRH II was, however, significantly reduced in tumour biopsies following hormone ablation. This was further investigated in a prostate xenograft model where androgens increased GnRH II levels, while their withdrawal reduced it. In cell lines, we confirmed high levels of GnRH II in androgen receptor (AR)-positive LNCaP cells but low levels in AR-negative PC3 cells. In LNCaP cells, GnRH II induction by androgens was blocked by the AR inhibitor casodex, but not by cycloheximide treatment. Sequence analysis subsequently revealed a putative androgen response element in the upstream region of the GnRH II gene and direct interaction with the AR was confirmed in chromatin immunoprecipitation experiments. Finally, to test whether the effects of GnRH II were dependent on AR expression, LNCaP and PC3 cells were exposed to exogenous peptide. In both cell lines, GnRH II inhibited cell proliferation and migration, suggesting that its function is independent of AR status. These results provide evidence that GnRH II is widely expressed in prostate cancer and is an AR-regulated gene. Further studies are warranted to characterise the effects of GnRH II on prostate cancer cells and investigate its potential value as a novel therapy.


Assuntos
Regulação Neoplásica da Expressão Gênica , Hormônio Liberador de Gonadotropina/análogos & derivados , Neoplasias da Próstata/genética , Receptores Androgênicos/fisiologia , Androgênios/farmacologia , Animais , Sequência de Bases , Sítios de Ligação , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/genética , Hormônio Liberador de Gonadotropina/metabolismo , Humanos , Masculino , Camundongos , Camundongos Nus , Dados de Sequência Molecular , Invasividade Neoplásica , Neoplasias Hormônio-Dependentes/genética , Neoplasias Hormônio-Dependentes/metabolismo , Neoplasias Hormônio-Dependentes/patologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Receptores Androgênicos/metabolismo , Elementos de Resposta , Transplante Heterólogo , Células Tumorais Cultivadas
10.
Br Dent J ; 202(9): 508, 2007 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-17496843
11.
Biochem Soc Trans ; 35(Pt 3): 574-6, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17511655

RESUMO

The insidious progression of AD (Alzheimer's disease) is believed to be linked closely to the production, accumulation and aggregation of the approximately 4.5 kDa protein fragment called Abeta (amyloid beta-peptide). Abeta is produced by sequential cleavage of the amyloid precursor protein by two enzymes referred to as beta- and gamma-secretase. beta-Secretase is of central importance, as it catalyses the rate-limiting step in the production of Abeta and was identified 7 years ago as BACE1 (beta-site APP-cleaving enzyme 1). Soon afterwards, its homologue BACE2 was discovered, and both proteins represent a new subclass of the aspartyl protease family. Studies examining the regulation and function of beta-secretase in the normal and AD brain are central to the understanding of excessive production of Abeta in AD, and in targeting and normalizing this beta-secretase process if it has gone awry in the disease. Several reports indicate this, showing increased beta-secretase activity in AD, with recent findings by our group showing changes in beta-secretase enzyme kinetics in AD brain caused by an increased V(max). This article gives a brief review of studies which have examined BACE1 protein levels and beta-secretase activity in control and AD brain, considering further the expression of BACE2 in the human brain.


Assuntos
Doença de Alzheimer/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Encéfalo/metabolismo , Doença de Alzheimer/genética , Sequência de Aminoácidos , Secretases da Proteína Precursora do Amiloide/genética , Precursor de Proteína beta-Amiloide/química , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Ácido Aspártico Endopeptidases/genética , Sítios de Ligação , Humanos , Cinética , Dados de Sequência Molecular , Processamento de Proteína Pós-Traducional , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
12.
J Hosp Infect ; 62(3): 285-99, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16337712

RESUMO

Infection control input is vital throughout the planning, design and building stages of a new hospital project, and must continue through the commissioning (and decommissioning) process, evaluation and putting the facility into full clinical service. Many hospitals continue to experience problems months or years after occupying the new premises; some of these could have been avoided by infection control involvement earlier in the project. The importance of infection control must be recognized by the chief executive of the hospital trust and project teams overseeing the development. Clinical user groups and contractors must also be made aware of infection control issues. It is vital that good working relationships are built up between the infection control team (ICT) and all these parties. ICTs need the authority to influence the process. This may require their specific recognition by the Private Finance Initiative National Unit, the Department of Health or other relevant authorities. ICTs need training in how to read design plans, how to write effective specifications, and in other areas with which they may be unfamiliar. The importance of documentation and record keeping is paramount. External or independent validation of processes should be available, particularly in commissioning processes. Building design in relation to infection control needs stricter national regulations, allowing ICTs to focus on more local usage issues. Further research is needed to provide evidence regarding the relationship between building design and the prevalence of infection.


Assuntos
Infecção Hospitalar/prevenção & controle , Arquitetura Hospitalar/normas , Controle de Infecções/normas , Engenharia Sanitária/normas , Documentação , Hospitais Públicos/normas , Humanos , Reino Unido
13.
J Hosp Infect ; 49(1): 48-54, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11516186

RESUMO

We report on a post-operative infection surveillance system which includes post-discharge follow-up, developed over five years in a district general hospital in the West Midlands, UK. The methods used for following up 667 patients undergoing one of five representative surgical procedures are described. Emergency, elective and day-case procedures are included. A combination of healthcare worker questionnaire, telephone calls and patient questionnaire gave a follow-up rate of 92.7%. The system took infection control staff an average of 40 min per patient (30 min inpatient assessment, 10 min post-discharge). Almost half (48%) of surgical site infections were diagnosed after discharge from hospital. The system worked equally well when conducted as part of the UK Nosocomial Infection National Surveillance Scheme (NINSS), or as in-house projects. It is likely that the system could be used in other areas with similar population characteristics and support from local general practitioners working in the community.


Assuntos
Assistência ao Convalescente , Controle de Infecções/métodos , Vigilância da População/métodos , Infecção da Ferida Cirúrgica/epidemiologia , Inglaterra/epidemiologia , Hospitais de Distrito , Hospitais Gerais , Humanos , Controle de Infecções/organização & administração , Inquéritos e Questionários , Telefone
14.
Opt Lett ; 24(1): 55-7, 1999 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-18071406

RESUMO

We present what we believe to be the first implementation of a Fabry-Perot (FP) etalon using polymer cholesteric liquid-crystal mirrors. These polymer mirrors have each been fabricated onto a single substrate, which allows the FP cavity spacing to be only a few micrometers wide. For the experimental results presented, cavity lengths of 13.8 and 7.6 microm yield near-infrared free spectral ranges of 24.8 and 45.6 nm, respectively. The measured finesse of 14.31 is approaching the limitation imposed by the reflectivity of the mirrors.

16.
Opt Lett ; 19(10): 758-60, 1994 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-19844436

RESUMO

We report what is to our knowledge the first implementation of a broadband analog intensity modulator composed of two chiral smectic liquid-crystal half-wave retarders. A reflection-mode intensity modulator employing a single active device has also demonstrated achromatic transmission. A quantitative theory for chromatic compensation is presented. By optimum selection of liquid-crystal retardance and orientation, intensity transmission is uniform throughout the visible. The chiral smectic liquid-crystal devices used in the implementation are capable of switching in less than 20 micros.

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