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1.
Epidemiol Infect ; 147: e163, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-31063101

RESUMO

Influenza and respiratory syncytial virus (RSV) are common causes of respiratory tract infections and place a burden on health services each winter. Systems to describe the timing and intensity of such activity will improve the public health response and deployment of interventions to these pressures. Here we develop early warning and activity intensity thresholds for monitoring influenza and RSV using two novel data sources: general practitioner out-of-hours consultations (GP OOH) and telehealth calls (NHS 111). Moving Epidemic Method (MEM) thresholds were developed for winter 2017-2018. The NHS 111 cold/flu threshold was breached several weeks in advance of other systems. The NHS 111 RSV epidemic threshold was breached in week 41, in advance of RSV laboratory reporting. Combining the use of MEM thresholds with daily monitoring of NHS 111 and GP OOH syndromic surveillance systems provides the potential to alert to threshold breaches in real-time. An advantage of using thresholds across different health systems is the ability to capture a range of healthcare-seeking behaviour, which may reflect differences in disease severity. This study also provides a quantifiable measure of seasonal RSV activity, which contributes to our understanding of RSV activity in advance of the potential introduction of new RSV vaccines.


Assuntos
Influenza Humana/epidemiologia , Influenza Humana/patologia , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/patologia , Vigilância de Evento Sentinela , Inglaterra/epidemiologia , Humanos , Encaminhamento e Consulta , Telemedicina/métodos
2.
Epidemiol Infect ; 145(9): 1922-1932, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28413995

RESUMO

Seasonal respiratory illnesses present a major burden on primary care services. We assessed the burden of respiratory illness on a national telehealth system in England and investigated the potential for providing early warning of respiratory infection. We compared weekly laboratory reports for respiratory pathogens with telehealth calls (NHS 111) between week 40 in 2013 and week 29 in 2015. Multiple linear regression was used to identify which pathogens had a significant association with respiratory calls. Children aged <5 and 5-14 years, and adults over 65 years were modelled separately as were time lags of up to 4 weeks between calls and laboratory specimen dates. Associations with respiratory pathogens explained over 83% of the variation in cold/flu, cough and difficulty breathing calls. Based on the first two seasons available, the greatest burden was associated with respiratory syncytial virus (RSV) and influenza, with associations found in all age bands. The most sensitive signal for influenza was calls for 'cold/flu', whilst for RSV it was calls for cough. The best-fitting models showed calls increasing a week before laboratory specimen dates. Daily surveillance of these calls can provide early warning of seasonal rises in influenza and RSV, contributing to the national respiratory surveillance programme.


Assuntos
Infecções Respiratórias/epidemiologia , Telemedicina/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Inglaterra/epidemiologia , Humanos , Lactente , Recém-Nascido , Influenza Humana/epidemiologia , Influenza Humana/virologia , Pessoa de Meia-Idade , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/virologia , Infecções Respiratórias/virologia , Estações do Ano , Adulto Jovem
3.
J Public Health (Oxf) ; 39(1): 184-192, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-26956114

RESUMO

Background: Public Health England (PHE) coordinates a suite of real-time national syndromic surveillance systems monitoring general practice, emergency department and remote health advice data. We describe the development and informal evaluation of a new syndromic surveillance system using NHS 111 remote health advice data. Methods: NHS 111 syndromic indicators were monitored daily at national and local level. Statistical models were applied to daily data to identify significant exceedances; statistical baselines were developed for each syndrome and area using a multi-level hierarchical mixed effects model. Results: Between November 2013 and October 2014, there were on average 19 095 NHS 111 calls each weekday and 43 084 each weekend day in the PHE dataset. There was a predominance of females using the service (57%); highest percentage of calls received was in the age group 1-4 years (14%). This system was used to monitor respiratory and gastrointestinal infections over the winter of 2013-14, the potential public health impact of severe flooding across parts of southern England and poor air quality episodes across England in April 2014. Conclusions: This new system complements and supplements the existing PHE syndromic surveillance systems and is now integrated into the routine daily processes that form this national syndromic surveillance service.


Assuntos
Vigilância da População/métodos , Saúde Pública , Estatística como Assunto/normas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Serviço Hospitalar de Emergência , Inglaterra/epidemiologia , Feminino , Medicina Geral , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Consulta Remota , Medicina Estatal , Adulto Jovem
4.
Nat Genet ; 6(1): 98-105, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8136842

RESUMO

Modifications to exon amplification have been instituted that increase its speed, efficiency and reliability. Exons were isolated from target human or mouse genomic DNA sources ranging from 30 kilobases (kb) to 3 megabases (Mb) in complexity. The efficiency was dependent upon the amount of input DNA, and ranged from isolation of an exon for every 20 kb to an exon for every 80 kb of target genomic DNA. In these studies, several novel genes and a smaller number of genes isolated previously that reside on human chromosome 9 have been identified. These results indicate that exon amplification is presently adaptable to large scale isolation of exons from complex sources of genomic DNA.


Assuntos
DNA/genética , Éxons , Amplificação de Genes , Animais , Sequência de Bases , Carboxilesterase , Hidrolases de Éster Carboxílico/genética , Cromossomos Humanos Par 9 , DNA/isolamento & purificação , Primers do DNA/genética , Técnicas Genéticas , Humanos , Camundongos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
5.
Nat Genet ; 11(2): 210-2, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7550353

RESUMO

Many tumour types have been reported to have deletion of 9p21 (refs 1-6). A candidate target suppressor gene, p16 (p16INK4a/MTS-1/CDKN2), was recently identified within the commonly deleted region in tumour cell lines. An increasing and sometimes conflicting body of data has accumulated regarding the frequency of homozygous deletion and the importance of p16 in primary tumours. We tested 545 primary tumours by microsatellite analysis with existing and newly cloned markers around the p16 locus. We have now found that small homozygous deletions represent the predominant mechanism of inactivation at 9p21 in bladder tumours and are present in other tumour types, including breast and prostate cancer. Moreover, fine mapping of these deletions implicates a 170 kb minimal region that includes p16 and excludes p15.


Assuntos
Deleção Cromossômica , Genes Supressores de Tumor , Neoplasias/genética , Southern Blotting , Mapeamento Cromossômico , Cromossomos Humanos Par 9 , Sondas de DNA , DNA de Neoplasias/análise , DNA Satélite/análise , Feminino , Marcadores Genéticos , Homozigoto , Humanos , Hibridização in Situ Fluorescente , Masculino , Neoplasias/patologia , Reação em Cadeia da Polimerase
6.
Diabetologia ; 54(4): 819-27, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21181396

RESUMO

AIMS/HYPOTHESIS: We assessed whether per-arnt-sim (PAS) domain-containing protein kinase (PASK) is involved in the regulation of glucagon secretion. METHODS: mRNA levels were measured in islets by quantitative PCR and in pancreatic beta cells obtained by laser capture microdissection. Glucose tolerance, plasma hormone levels and islet hormone secretion were analysed in C57BL/6 Pask homozygote knockout mice (Pask-/-) and control littermates. Alpha-TC1-9 cells, human islets or cultured E13.5 rat pancreatic epithelia were transduced with anti-Pask or control small interfering RNAs, or with adenoviruses encoding enhanced green fluorescent protein or PASK. RESULTS: PASK expression was significantly lower in islets from human type 2 diabetic than control participants. PASK mRNA was present in alpha and beta cells from mouse islets. In Pask-/- mice, fasted blood glucose and plasma glucagon levels were 25 ± 5% and 50 ± 8% (mean ± SE) higher, respectively, than in control mice. At inhibitory glucose concentrations (10 mmol/l), islets from Pask-/- mice secreted 2.04 ± 0.2-fold (p < 0.01) more glucagon and 2.63 ± 0.3-fold (p < 0.01) less insulin than wild-type islets. Glucose failed to inhibit glucagon secretion from PASK-depleted alpha-TC1-9 cells, whereas PASK overexpression inhibited glucagon secretion from these cells and human islets. Extracellular insulin (20 nmol/l) inhibited glucagon secretion from control and PASK-deficient alpha-TC1-9 cells. PASK-depleted alpha-TC1-9 cells and pancreatic embryonic explants displayed increased expression of the preproglucagon (Gcg) and AMP-activated protein kinase (AMPK)-alpha2 (Prkaa2) genes, implying a possible role for AMPK-alpha2 downstream of PASK in the control of glucagon gene expression and release. CONCLUSIONS/INTERPRETATION: PASK is involved in the regulation of glucagon secretion by glucose and may be a useful target for the treatment of type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/enzimologia , Ilhotas Pancreáticas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Linhagem Celular , Células Cultivadas , Diabetes Mellitus Tipo 2/metabolismo , Glucagon/metabolismo , Células Secretoras de Glucagon/efeitos dos fármacos , Células Secretoras de Glucagon/metabolismo , Glucose/farmacologia , Humanos , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/efeitos dos fármacos , Camundongos , Camundongos Mutantes , Modelos Biológicos , Reação em Cadeia da Polimerase , Proteínas Serina-Treonina Quinases/genética , Ratos
7.
Science ; 293(5529): 510-4, 2001 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-11441146

RESUMO

Clock:BMAL1 and NPAS2:BMAL1 are heterodimeric transcription factors that control gene expression as a function of the light-dark cycle. Although built to fluctuate at or near a 24-hour cycle, the clock can be entrained by light, activity, or food. Here we show that the DNA-binding activity of the Clock:BMAL1 and NPAS2:BMAL1 heterodimers is regulated by the redox state of nicotinamide adenine dinucleotide (NAD) cofactors in a purified system. The reduced forms of the redox cofactors, NAD(H) and NADP(H), strongly enhance DNA binding of the Clock:BMAL1 and NPAS2:BMAL1 heterodimers, whereas the oxidized forms inhibit. These observations raise the possibility that food, neuronal activity, or both may entrain the circadian clock by direct modulation of cellular redox state.


Assuntos
Proteínas de Ligação a DNA , DNA/metabolismo , NADP/metabolismo , NAD/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptores de Hidrocarboneto Arílico , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição ARNTL , Animais , Translocador Nuclear Receptor Aril Hidrocarboneto , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Relógios Biológicos , Proteínas CLOCK , Linhagem Celular , Ritmo Circadiano , Dimerização , Sequências Hélice-Alça-Hélice , Humanos , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , Camundongos , NAD/farmacologia , NADP/farmacologia , Proteínas do Tecido Nervoso/química , Oxirredução , Proteínas Recombinantes/metabolismo , Transativadores/química , Fatores de Transcrição/química
8.
Science ; 288(5474): 2226-30, 2000 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-10864874

RESUMO

Neuronal PAS domain protein 2 (NPAS2) is a basic helix-loop-helix (bHLH) PAS domain transcription factor expressed in multiple regions of the vertebrate brain. Targeted insertion of a beta-galactosidase reporter gene (lacZ) resulted in the production of an NPAS2-lacZ fusion protein and an altered form of NPAS2 lacking the bHLH domain. The neuroanatomical expression pattern of NPAS2-lacZ was temporally and spatially coincident with formation of the mature frontal association/limbic forebrain pathway. NPAS2-deficient mice were subjected to a series of behavioral tests and were found to exhibit deficits in the long-term memory arm of the cued and contextual fear task. Thus, NPAS2 may serve a dedicated regulatory role in the acquisition of specific types of memory.


Assuntos
Encéfalo/fisiologia , Aprendizagem/fisiologia , Memória/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Fatores de Transcrição/fisiologia , Animais , Aprendizagem da Esquiva , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Comportamento Animal , Encéfalo/metabolismo , Condicionamento Psicológico , Sinais (Psicologia) , Medo , Marcação de Genes , Sequências Hélice-Alça-Hélice , Sistema Límbico/metabolismo , Sistema Límbico/fisiologia , Masculino , Camundongos , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/genética , Prosencéfalo/metabolismo , Prosencéfalo/fisiologia , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Tato , Fatores de Transcrição/química , Fatores de Transcrição/genética , Ativação Transcricional , Transfecção , beta-Galactosidase/metabolismo
9.
Neuroscience ; 152(3): 773-84, 2008 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-18313226

RESUMO

3,4-Methylenedioxymethamphetamine (MDMA or ecstasy) stimulates the transporter-mediated release of monoamines, including 5-HT. High-dose exposure to MDMA causes persistent 5-HT deficits (e.g. depletion of brain 5-HT) in animals, yet the functional and clinical relevance of such deficits are poorly defined. Here we examine functional consequences of MDMA-induced 5-HT depletions in rats. Male rats received binges of three i.p. injections of MDMA or saline, one injection every 2 h; MDMA was given at a threshold pharmacological dose (1.5 mg/kgx3, low dose) or at a fivefold higher amount (7.5 mg/kgx3, high dose). One week later, jugular catheters and intracerebral guide cannulae were implanted. Two weeks after binges, rats received acute i.v. challenge injections of 1 and 3 mg/kg MDMA. Neuroendocrine effects evoked by i.v. MDMA (prolactin and corticosterone secretion) were assessed via serial blood sampling, while neurochemical effects (5-HT and dopamine release) were assessed via microdialysis in brain. MDMA binges elevated core temperatures only in the high-dose group, with these same rats exhibiting approximately 50% loss of forebrain 5-HT 2 weeks later. Prior exposure to MDMA did not alter baseline plasma hormones or dialysate monoamines, and effects of i.v. MDMA were similar in saline and low-dose groups. By contrast, rats pretreated with high-dose MDMA displayed significant reductions in evoked hormone secretion and 5-HT release when challenged with i.v. MDMA. As tolerance developed only in rats exposed to high-dose binges, hyperthermia and 5-HT depletion are implicated in this phenomenon. Our results suggest that MDMA tolerance in humans may reflect 5-HT deficits which could contribute to further dose escalation.


Assuntos
Encéfalo/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Tolerância a Medicamentos , N-Metil-3,4-Metilenodioxianfetamina/toxicidade , Serotoninérgicos/toxicidade , Serotonina/deficiência , Animais , Temperatura Corporal/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Dopamina/metabolismo , Relação Dose-Resposta a Droga , Esquema de Medicação , Líquido Extracelular/efeitos dos fármacos , Líquido Extracelular/metabolismo , Febre/induzido quimicamente , Febre/metabolismo , Febre/fisiopatologia , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Infusões Intravenosas , Infusões Parenterais , Masculino , Microdiálise , Ratos , Ratos Sprague-Dawley , Serotonina/metabolismo , Transmissão Sináptica/efeitos dos fármacos
10.
J Gastrointest Surg ; 21(12): 2000-2008, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28815471

RESUMO

INTRODUCTION: Centralization of gastric cancer surgery is thought to improve outcome and has been imposed in the Netherlands since 2012. This study analyzes the effect of centralization in terms of treatment outcome and survival in the Eastern part of the Netherlands. METHODS: All gastric cancer patients without distant metastases who underwent a gastrectomy in six hospitals in the Eastern part of the Netherlands between 2008 and 2011 (pre-centralization) and 2013-2016 (post-centralization) were selected from the Netherlands Cancer Registry. Patient and tumor characteristics and treatment outcomes (duration of surgery, blood loss, resection margin, lymphadenectomy, chemotherapy, postoperative complications and hospital stay, and overall and disease-free survival) were analyzed and compared between pre- and post-centralization. RESULTS: One hundred forty-four patients were included pre-centralization and 106 patients post-centralization. Patient and tumor characteristics were almost similar in the two periods. After centralization, more patients were treated with perioperative chemotherapy (25 vs. 42% p < 0.01). The proportion of patients treated with an adequate lymphadenectomy (21 vs. 93% p < 0.01) and laparoscopic surgery (6 vs. 40% p < 0.01) increased significantly (p < 0.01). The amount of cardiac complications (16 vs. 7.5% p < 0.05) decreased; however, complications needing a re-intervention were comparable (42 vs. 40% p = 0.79). Median hospital stay decreased from 10 to 8 days (p < 0.01). A 30-day mortality did not differ significantly (4.2 vs. 1.9%). A 1-year overall (78 vs. 80% p = 0.17) and disease-free survival (73 vs. 74% p = 0.66) remained stable. DISCUSSION: Centralizing gastric cancer treatment in the Eastern part of the Netherlands resulted in improved lymph node harvesting and a successful introduction of laparoscopic gastrectomies. Centralization has not translated into improved mortality, and other variables may also have led to these improved outcomes. Further research using a nationwide population-based study will be needed to confirm these data.


Assuntos
Institutos de Câncer/estatística & dados numéricos , Atenção à Saúde/organização & administração , Gastrectomia/efeitos adversos , Complicações Pós-Operatórias/etiologia , Neoplasias Gástricas/cirurgia , Idoso , Quimioterapia Adjuvante/estatística & dados numéricos , Intervalo Livre de Doença , Feminino , Humanos , Laparoscopia/efeitos adversos , Laparoscopia/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Excisão de Linfonodo/estatística & dados numéricos , Masculino , Países Baixos , Complicações Pós-Operatórias/cirurgia , Sistema de Registros , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia , Taxa de Sobrevida , Resultado do Tratamento
11.
Cancer Res ; 54(20): 5262-4, 1994 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-7923151

RESUMO

The CDKN2 gene that encodes the cell cycle regulatory protein cyclin-dependent kinase-4 inhibitor (p16) has recently been mapped to chromosome 9p21. Frequent homozygous deletions of this gene have been documented in cell lines derived from different types of tumors, including breast tumors, suggesting that CDKN2 is a tumor suppressor gene involved in a wide variety of human cancers. To determine the frequency of CDKN2 mutations in breast carcinomas, we screened 37 primary tumors and 5 established breast tumor cell lines by single-strand conformation polymorphism analysis. In addition, Southern blot analysis was performed on a set of five primary breast carcinoma samples and five breast tumor cell lines. Two of the five tumor cell lines revealed a homozygous deletion of the CDKN2 gene, but no mutations were observed in any of the primary breast carcinomas. These results suggest that the mutation of the CDKN2 gene may not be a critical genetic change in the formation of primary breast carcinoma.


Assuntos
Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Carcinoma Lobular/genética , Proteínas de Transporte/genética , Deleção de Genes , Inibidor p16 de Quinase Dependente de Ciclina , Análise Mutacional de DNA , Humanos , Polimorfismo Conformacional de Fita Simples , Células Tumorais Cultivadas
12.
Cancer Res ; 58(23): 5321-5, 1998 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9850057

RESUMO

Matrix metalloproteinases (MMPs) facilitate cellular invasion by degrading the extracellular matrix, and their regulation is partially dependent on transcription. Binding sites for members of the Ets family of transcription factors are present within MMP promoters and are potent positive regulators. We report a single nucleotide polymorphism at -1607 bp in the MMP-1 promoter, where an additional guanine (G) creates an Ets binding site, 5'-GGA-3'. This polymorphism displays significantly higher transcription in normal fibroblasts and in melanoma cells than the 1 G polymorphism, and it binds substantially more nuclear extract and recombinant ETS-1. Analysis of control DNAs from the Center d'Etude du Polymorphisme Humain pedigrees reveals that this polymorphism is not a mutation, with a frequency of the 2 G polymorphism at 30%. In contrast, in eight tumor cell lines, this frequency increased to 62.5% (P < 0.0001). Thus, this MMP-1 polymorphism contributes to increased transcription, and cells expressing the 2 G polymorphism may provide a mechanism for more aggressive matrix degradation, thereby facilitating cancer progression.


Assuntos
Colagenases/genética , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica/fisiologia , Sítios de Ligação , Colagenases/biossíntese , Sequência Consenso , DNA/metabolismo , DNA de Neoplasias/metabolismo , Fibroblastos/enzimologia , Guanina/metabolismo , Guanina/fisiologia , Humanos , Metaloproteinase 1 da Matriz , Melanoma/enzimologia , Nucleotídeos/genética , Reação em Cadeia da Polimerase , Polimorfismo Genético , Proteína Proto-Oncogênica c-ets-1 , Proteínas Proto-Oncogênicas c-ets , Proteínas Proto-Oncogênicas c-jun/metabolismo , Fator de Transcrição AP-1/metabolismo
13.
Oncogene ; 14(5): 611-6, 1997 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-9053860

RESUMO

Formation of meningiomas has been associated with the loss of genetic material on chromosome 22. To approach the additional chromosomal events that underlie progression of these tumors to malignancy, we have examined several other chromosomal regions for loss of heterozygosity (LOH) in these tumors. Fifty-eight tumors, comprising 43 benign meningiomas, 11 atypical meningiomas and four malignant meningiomas, were examined. While the loss of chromosome 22 was seen in approximately half of all these tumors, regardless of their malignancy, the most frequent chromosomal losses observed in the malignant and atypical tumors were on the long arm of chromosome 14. Thirty-nine tumors were informative for at least one of the three markers on chromosome 14 that we tested. Of these, 7/14 malignant and atypical tumors showed LOH in contrast to only 1/25 benign tumors. Other loci that showed LOH in malignant tumors, although at a much lower frequency, were on chromosomes 17p and 1p. The high frequency of LOH for loci on chromosome 14q in atypical and malignant tumors suggests the presence of a tumor progression gene at this locus. In one of the malignant meningiomas heterozygosity was lost at D14S13 and D14S16 but retained at the proximal marker D14S43 as well as the more distal marker D14S23. This suggests that an interstitial deletion occurred in this tumor which should be useful for further refining the position of the putative tumor progression locus.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 14 , Neoplasias Meníngeas/genética , Meningioma/genética , Mapeamento Cromossômico , Cromossomos Humanos Par 22 , Marcadores Genéticos , Humanos , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/cirurgia , Meningioma/patologia , Meningioma/cirurgia , Reação em Cadeia da Polimerase , Polimorfismo Genético
14.
Clin Cancer Res ; 6(12): 4823-30, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11156241

RESUMO

Degradation of the extracellular matrix is the sine qua non of tumor invasion and metastasis. Most of this degradation is mediated by matrix metalloproteinases (MMPs), a family of enzymes that, collectively, degrades the extracellular matrix. Although the basement membrane-degrading enzymes, MMP-2 and MMP-9, have been given considerable attention for their roles in invasion and metastasis, the interstitial collagenases, a subfamily of MMPs that cleaves the stromal collagens types I and III, have received relatively little recognition for their part in these processes. This subfamily is comprised of collagenase 1 (MMP-1), collagenase 3 (MMP-13), and the MT-MMPs, membrane-bound MMPs, and numerous reports over the last several years document the expression of these MMPs in a wide variety of advancing tumors. Of particular interest is a single nucleotide polymorphism in the MMP-1 promoter that increases the transcription of this gene and that is associated with melanoma and with ovarian and endometrial cancers. The collagenases can mediate tumor invasion through several mechanisms, which include constitutive production of enzyme by the tumor cells, induction of collagenase production in the neighboring stromal cells, and interactions between tumor/ stromal cells to induce collagenase production by one or both cell types. Thus, evidence indicates that elevated expression of the interstitial collagenases is associated with a poor prognosis in a variety of cancers, and therefore, these MMPs can serve as a marker of tumor progression.


Assuntos
Colagenases/biossíntese , Neoplasias/enzimologia , Biomarcadores , Colagenases/genética , Progressão da Doença , Humanos , Metaloproteinase 1 da Matriz/biossíntese , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 13 da Matriz , Metaloproteinases da Matriz Associadas à Membrana , Metaloendopeptidases/biossíntese , Metaloendopeptidases/genética , Modelos Biológicos , Neoplasias/genética , Polimorfismo de Nucleotídeo Único
15.
Cancer Epidemiol Biomarkers Prev ; 10(6): 687-96, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11401920

RESUMO

Blood samples are an excellent source of large amounts of genomic DNA. However, alternative sources are often needed in epidemiological studies because of difficulties in obtaining blood samples. This report evaluates the buccal cytobrush and alcohol-containing mouthwash protocols for collecting DNA by mail. Several DNA extraction techniques are also evaluated. The study was conducted in two phases. In phase 1, we compared cytobrush and mouthwash samples collected by mail in two different epidemiological studies: (a) cytobrush samples (n = 120) from a United States case-control study of breast cancer; and (b) mouthwash samples (n = 40) from a prospective cohort of male United States farmers. Findings from phase 1 were confirmed in phase 2, where we randomized cytobrush (n = 28) and mouthwash (n = 25) samples among participants in the breast cancer study to directly compare both collection methods. The median human DNA yield determined by hybridization with a human DNA probe from phenol-chloroform extracts was 1.0 and 1.6 microg/2 brushes for phases 1 and 2, respectively, and 27.5 and 16.6 microg/mouthwash sample for phases 1 and 2, respectively. Most (94-100%) mouthwash extracts contained high molecular weight DNA (>23 kb), in contrast to 55-61% of the brush extracts. PCR success rates for amplification of beta-globin gene fragments (268, 536, and 989 bp) were similar for cytobrush and mouthwash phenol-chloroform extracts (range, 94.4-100%). Also, we obtained high success rates in determining the number of CAG repeats in the androgen receptor gene, characterizing tetranucleotide microsatellites in six gene loci, and screening for mutations in the BRCA1/2 genes in a subset of phenol-chloroform DNA extracts. Relative to DNA extracted by phenol-chloroform from cytobrush samples, DNA extracted by NaOH had lower molecular weight, decreased PCR success rates for most assays performed, and unreliably high spectrophotometer readings for DNA yields. In conclusion, although DNA isolated from either mouthwash or cytobrush samples collected by mail from adults is adequate for a wide range of PCR-based assays, a single mouthwash sample provides substantially larger amounts and higher molecular weight DNA than two cytobrush samples.


Assuntos
DNA/análise , Estudos Epidemiológicos , Reação em Cadeia da Polimerase , Adulto , Idoso , Neoplasias da Mama , Feminino , Humanos , Pessoa de Meia-Idade , Mucosa Bucal/citologia , Antissépticos Bucais , Reprodutibilidade dos Testes , Manejo de Espécimes
16.
Neuropharmacology ; 30(4): 307-11, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1852265

RESUMO

In vivo microdialysis was used to examine the effects of 5-methoxy-3-(1,2,3,6-tetrahydro-4-pyridinyl)-1H-indole (RU24969) and 1-(m-trifluoromethylphenyl)piperazine (TFMPP) on extracellular 5-hydroxytryptamine (5-HT) in the diencephalon of unanesthetized rats. Both RU24969 and TFMPP are potent 5-HT autoreceptor agonists but both compounds caused a dose-dependent increase in extracellular 5-HT, when infused into the diencephalon at micromolar concentrations. The piperazine compound, TFMPP, also caused an increase in 5-HT when administered peripherally (2.5-10 mg/kg i.p.). In contrast, peripheral administration of RU24969 (2.5 mg/kg i.p.) caused a decrease in extracellular 5-HT. Since the effects of local infusion with RU24969 and TFMPP were not additive with the increase produced by the inhibitor of the uptake of 5-HT, fluoxetine, these compounds may be acting at the site of the membrane carrier. These results suggest that direct 5-HT1 agonist activity is not the only factor involved in the physiological and behavioral consequences of peripheral administration of TFMPP.


Assuntos
Diencéfalo/metabolismo , Indóis/farmacologia , Piperazinas/farmacologia , Serotonina/metabolismo , Animais , Diálise/métodos , Diencéfalo/efeitos dos fármacos , Relação Dose-Resposta a Droga , Espaço Extracelular/efeitos dos fármacos , Espaço Extracelular/metabolismo , Fluoxetina/farmacologia , Masculino , Ratos
17.
Neuropharmacology ; 32(12): 1381-6, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8152528

RESUMO

The serotonin (5-HT) agonist 1-(m-chlorophenyl)piperazine (mCPP) has been widely used as a pharmacological probe to assess 5-HT function. Although mCPP is known to interact with 5-HT receptors, this drug is also reported to exhibit presynaptic actions that increase extraneuronal 5-HT in vitro. In the present study, we used in vivo microdialysis to examine the effects of mCPP on extracellular 5-HT in the ventromedial diencephalon of awake rats. Intravenous mCPP (1.0 and 2.0 mg/kg) increased dialysate 5-HT in a dose-related manner, with extracellular 5-HT levels rising 8-fold above baseline after the high dose of drug. The stimulatory effect of mCPP on dialysate 5-HT was abolished by pretreatment with the 5-HT uptake blocker fluoxetine (10 mg/kg, i.p.). In complementary experiments, mCPP elevated plasma prolactin at doses equivalent to those that increased dialysate 5-HT, and fluoxetine pretreatment caused a partial, though significant, attenuation of mCPP-induced prolactin release. These results indicate that mCPP increases extracellular 5-HT in rat brain by a presynaptic mechanism involving 5-HT transporters. Moreover, the plasma prolactin response to mCPP is at least partially mediated by the presynaptic actions of the drug. Our data further suggest the possibility that mCPP exhibits indirect agonist properties in human brain. Therefore, clinical studies designed to evaluate postsynaptic 5-HT receptor sensitivity based on responsiveness to mCPP should be interpreted with caution.


Assuntos
Diencéfalo/metabolismo , Fluoxetina/farmacologia , Piperazinas/farmacologia , Agonistas do Receptor de Serotonina/farmacologia , Serotonina/metabolismo , Animais , Diencéfalo/efeitos dos fármacos , Injeções Intravenosas , Cinética , Masculino , Microdiálise , Piperazinas/administração & dosagem , Prolactina/sangue , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
18.
Ann N Y Acad Sci ; 878: 466-86, 1999 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-10415749

RESUMO

Cancer mortality usually results from the tumor invading the local environment and metastasizing to vital organs, e.g. liver, lung, and brain. Degradation of the extracellular matrix is, therefore, the sine qua non of tumor cell invasion. this degradation is mediated mainly by MMPs, and thus, inhibition of MMP synthesis is a target for anticancer agents. Tumor cells must traverse both the basement membrane (type IV collagen) and the interstitial stroma (type I collagen). Therefore, we used scanning electron microscopy to examine the invasive behavior of several aggressive tumor cell lines, A2058 melanoma cells, and SCC and FaDu squamous cell carcinomas through these matrices; and we monitored the ability of all-trans retinoic acid and several RAR-specific ligands to block invasion. We demonstrate that several retinoids, which are specific RAR alpha, beta, or gamma agonists/antagonists, selectively inhibited MMP synthesis in the three tumor cell lines. However, there was not a common pattern of MMP inhibition by a particular retinoid. For instance, a RAR alpha antagonist suppressed MMP-1 and MMP-2 synthesis in the melanoma cell line, but not in the FaDu or SCC-25 cells. On the other hand, synthesis of MMP-1 and MMP-9 by the FaDu cells was affected hardly at all, while a RAR gamma antagonist reduced the levels of MMP-2. Only all-trans retinoic acid reduced MMP-1 synthesis in these cells. We postulate that the differences may be related to a differential pattern of RAR expression in each of these cells, and that the RARs expressed by each cell line may not be targets of these RAR specific compounds. All-trans retinoic acid is a pan ligand, binding to all three RARs and, therefore, may modulate gene expression more generally. We conclude that the power of these new ligands lies in their specificity, which can be directed towards modulating expression of certain RARs and, thus, of certain MMPs. By blocking MMP synthesis, retinoids may be effective in cancer therapy by decreasing tumor invasiveness.


Assuntos
Metaloendopeptidases/antagonistas & inibidores , Metaloendopeptidases/genética , Invasividade Neoplásica/prevenção & controle , Inibidores de Proteases/farmacologia , Retinoides/farmacologia , Carcinoma de Células Escamosas , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Melanoma , Transcrição Gênica/efeitos dos fármacos , Células Tumorais Cultivadas
20.
J Med Microbiol ; 19(2): 247-55, 1985 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2858594

RESUMO

The virulence of Bordetella bronchiseptica in gnotobiotic piglets was studied by intranasal infection with 11 cultures derived from eight strains isolated from pigs (4), dogs (2), a human subject and a monkey. Six of the cultures contained organisms in phase I and five contained phenotypically different phase-III or -IV organisms. Of the phase-III and -IV cultures, four were derived from strains that had been isolated in phase I. Colonisation of the nasal cavity was investigated by counting bacteria in nasal swabs and washings. The toxigenicity of cell extracts from each strain and variant was determined by tests of lethality in mice or of cytopathogenicity in cell cultures. The results showed that two phase-I cultures from pigs colonised the nasal cavity and respiratory tract of gnotobiotic piglets better than did four phase-I cultures from other species. Phase-I organisms invariably produced capsules, fimbriae and mannose-resistant haemagglutination of guinea-pig erythrocytes. Four of five cultures in phases III and IV consisted of organisms that did not produce capsules, fimbriae or haemagglutination and colonised the nasal cavity poorly. Phase variation from I to III occurred in culture and in vivo, but variation from III to I occurred in vivo only and was accompanied by enhanced colonisation. Gnotobiotic piglets infected with porcine phase-I organisms exhibited atrophy of the nasal turbinate bones after 28 days; these organisms produced significantly more toxin than did bacteria in phase I from other species, or those in phases III and IV.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Bordetella/patogenicidade , Cavidade Nasal/microbiologia , Sistema Respiratório/microbiologia , Animais , Anticorpos Antibacterianos/biossíntese , Atrofia , Toxinas Bacterianas/biossíntese , Bordetella/crescimento & desenvolvimento , Bordetella/imunologia , Bordetella/isolamento & purificação , Infecções por Bordetella/microbiologia , Infecções por Bordetella/patologia , Bovinos , Linhagem Celular , Fímbrias Bacterianas/ultraestrutura , Vida Livre de Germes , Hemaglutinação , Infecções Respiratórias/microbiologia , Suínos , Conchas Nasais/patologia , Virulência
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