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1.
Hum Mutat ; 39(7): 914-924, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29704307

RESUMO

Rett syndrome (RTT) is a monogenic rare disorder that causes severe neurological problems. In most cases, it results from a loss-of-function mutation in the gene encoding methyl-CPG-binding protein 2 (MECP2). Currently, about 900 unique MECP2 variations (benign and pathogenic) have been identified and it is suspected that the different mutations contribute to different levels of disease severity. For researchers and clinicians, it is important that genotype-phenotype information is available to identify disease-causing mutations for diagnosis, to aid in clinical management of the disorder, and to provide counseling for parents. In this study, 13 genotype-phenotype databases were surveyed for their general functionality and availability of RTT-specific MECP2 variation data. For each database, we investigated findability and interoperability alongside practical user functionality, and type and amount of genetic and phenotype data. The main conclusions are that, as well as being challenging to find these databases and specific MECP2 variants held within, interoperability is as yet poorly developed and requires effort to search across databases. Nevertheless, we found several thousand online database entries for MECP2 variations and their associated phenotypes, diagnosis, or predicted variant effects, which is a good starting point for researchers and clinicians who want to provide, annotate, and use the data.


Assuntos
Bases de Dados Genéticas , Proteína 2 de Ligação a Metil-CpG/genética , Síndrome de Rett/genética , Feminino , Genótipo , Humanos , Mutação com Perda de Função/genética , Masculino , Mutação/genética , Fenótipo , Síndrome de Rett/patologia
2.
Int J Cancer ; 142(6): 1189-1201, 2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29114875

RESUMO

Evidence from in vivo, in vitro and ecological studies are suggestive of a protective effect of vitamin D against pancreatic cancer (PC). However, this has not been confirmed by analytical epidemiological studies. We aimed to examine the association between pre-diagnostic circulating vitamin D concentrations and PC incidence in European populations. We conducted a pooled nested case-control study within the European Prospective Investigation into Cancer and Nutrition (EPIC) and the Nord-Trøndelag Health Study's second survey (HUNT2) cohorts. In total, 738 primary incident PC cases (EPIC n = 626; HUNT2 n = 112; median follow-up = 6.9 years) were matched to 738 controls. Vitamin D [25(OH)D2 and 25(OH)D3 combined] concentrations were determined using isotope-dilution liquid chromatography-tandem mass spectrometry. Conditional logistic regression models with adjustments for body mass index and smoking habits were used to estimate incidence rate ratios (IRRs) and 95% confidence intervals (95%CI). Compared with a reference category of >50 to 75 nmol/L vitamin D, the IRRs (95% CIs) were 0.71 (0.42-1.20); 0.94 (0.72-1.22); 1.12 (0.82-1.53) and 1.26 (0.79-2.01) for clinically pre-defined categories of ≤25; >25 to 50; >75 to 100; and >100 nmol/L vitamin D, respectively (p for trend = 0.09). Corresponding analyses by quintiles of season-standardized vitamin D concentrations also did not reveal associations with PC risk (p for trend = 0.23). Although these findings among participants from the largest combination of European cohort studies to date show increasing effect estimates of PC risk with increasing pre-diagnostic concentrations of vitamin D, they are not statistically significant.


Assuntos
25-Hidroxivitamina D 2/sangue , Calcifediol/sangue , Neoplasias Pancreáticas/epidemiologia , Idoso , Estudos de Casos e Controles , Europa (Continente) , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/sangue , Estudos Prospectivos , Medição de Risco , Estações do Ano
3.
Artigo em Inglês | MEDLINE | ID: mdl-39163321

RESUMO

INTRODUCTION: Refractory pain is a major clinical problem in patients with pancreatic ductal adenocarcinoma (PDAC) and chronic pancreatitis (CP). New, effective therapies to reduce pain are urgently needed. Intravenous lidocaine is used in clinical practice in patients with PDAC and CP, but its efficacy has not been studied prospectively. METHODS: Multicentre prospective non-randomized pilot study including patients with moderate or severe pain (NRS ≥ 4) associated with PDAC or CP in 5 Dutch centers. An intravenous lidocaine bolus of 1.5mg/kg, was followed by continuous infusion at 1.5 mg/kg/hour. The dose was raised every 15 minutes until treatment response (up to a maximum 2mg/kg/hour) and consecutively administered for two hours. Primary outcome was the mean difference in pain severity, pre-infusion and the first day after (Brief Pain Inventory [BPI] scale 1-10). A BPI decrease ≥ 1.3 points was considered clinically relevant. RESULTS: Overall, 30 patients were included, 19 with PDAC (63%) and 11 with CP (37%). The mean difference in BPI at day one was 1.1 (SD±1.3) points for patients with PDAC and 0.5 (SD±1.7) for CP patients. A clinically relevant decrease in BPI on day one was reported in 9/29 patients (31%), this response lasted up to one month. No serious complications were reported, and only three minor complications (vertigo, nausea, tingling of mouth). Treatment with lidocaine did not impact quality of life. CONCLUSION: Intravenous lidocaine in patients with painful PDAC and CP did not show an overall clinically relevant reduction of pain. However, this pilot study shows that the treatment is feasible in this patient group, and had a positive effect in a third of patients which lasted up to a month with only minor side effects. To prove or exclude the efficacy of intravenous lidocaine, the study should be performed in a study with a greater sample size and less heterogeneous patient group.

4.
Pharmacoepidemiol Drug Saf ; 20(8): 830-7, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21648012

RESUMO

PURPOSE: Subjects using functional foods with approved health claims may be more likely to be non-adherent with prescribed drug therapy. This study aimed to assess the influence of the use of phytosterol/-stanol-enriched functional foods on adherence to statin therapy among patients initiating treatment. METHODS: We used data from the statin intervention research project, a randomized controlled trial aimed at improving adherence to statins. In the trial, new statin users were randomized to receive either usual care or extensive pharmaceutical care consisting of five individual counseling sessions. Customary use of phytosterol/-stanol-enriched products was identified by questionnaires filled out by all participants. Automated pharmacy-dispensing records were used to assess adherence in terms of discontinuation of therapy and the medication possession ratio. Analyses were performed for the overall population, as well as stratified for receiving pharmaceutical or usual care. RESULTS: The use of functional foods enriched with phytosterols/-stanols was not related to discontinuation of statin therapy, neither in the overall population (overall population adjusted hazard rate ratio (HR(adj)): 0.80 [95%CI: 0.59-1.08]), nor when stratified by randomization arm (pharmaceutical care HR(adj): 0.77 [95%CI: 0.49-1.23]); usual care HR(adj): 0.81 [95%CI: 0.54-1.21]). The median medication possession ratio was significantly lower in users of phytosterols/-stanols in the usual care group, but the difference was not clinically relevant. CONCLUSIONS: Customary use of phytosterol/-stanol-enriched functional foods did not affect adherence to statins in new users that are well informed on the beneficial effects of statin therapy. In daily medical practice, general practitioners and pharmacists should urge subjects not to take phytosterol/-stanol-enriched functional foods as replacement for their prescribed medication.


Assuntos
Alimentos Fortificados , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Adesão à Medicação , Fitosteróis/administração & dosagem , Idoso , Aconselhamento Diretivo/métodos , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Masculino , Pessoa de Meia-Idade , Assistência Farmacêutica/organização & administração , Farmacêuticos/organização & administração , Inquéritos e Questionários
5.
Int J Cancer ; 123(8): 1974-7, 2008 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-18661525

RESUMO

Several human and animal studies have shown that n-3 polyunsaturated fatty acids (PUFA) might be associated with a decreased risk, whereas other studies showed that n-6 PUFA may be associated with an increased risk of colorectal cancer. However, results from these studies are not consistent. We evaluated the associations between serum n-3 and n-6 PUFA levels and colorectal adenoma risk in an endoscopy-based case-control study, conducted in The Netherlands between 1997 and 2002. We included 363 cases of colorectal adenomas and 498 adenoma-free controls. Serum fatty acids were measured in cholesteryl esters. Logistic regression models were used to calculate odds ratios (OR), which were adjusted for age, gender and alcohol intake. Total serum n-3 PUFA levels were inversely associated with colorectal adenoma risk, the OR comparing the third tertile with the first tertile was 0.67 [95% confidence interval (CI) 0.46-0.96, p for trend = 0.03]. Serum eicosapentaenoic acid (EPA; C20:5n-3) and docosahexaenoic acid (DHA; C22:6n-3) and the n-3/n-6 ratio were inversely associated with colorectal adenoma risk, but these were not statistically significant. In contrast, the risk of colorectal adenomas was increased by total n-6 PUFA with an OR of 1.68 (95% CI, 1.17-2.42, p for trend = 0.006) and by linoleic acid (LA; C18:2n-6) with an OR of 1.65 (95% CI, 1.15-2.38, p for trend = 0.007). This is the first observational study that simultaneously finds an inverse association of serum n-3 PUFA and a positive association of n-6 PUFA with colorectal adenoma risk.


Assuntos
Adenoma/sangue , Neoplasias Colorretais/sangue , Ácidos Graxos Ômega-3/sangue , Ácidos Graxos Ômega-6/sangue , Adenoma/patologia , Estudos de Casos e Controles , Neoplasias Colorretais/patologia , Endoscopia Gastrointestinal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/sangue , Lesões Pré-Cancerosas/patologia , Fatores de Risco
6.
Cancer Res ; 66(5): 2608-15, 2006 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-16510579

RESUMO

Nevi and melanomas correlate to childhood and intermittent solar UV exposure, xeroderma pigmentosum patients run increased risk, and p16(Ink4a) expression is often lost in malignant progression. To ascertain the effect of these risk factors, pigmented hairless Ink4a/Arf-, Xpa- knockout mice were subjected to various combinations of neonatal [7,12-dimethylbenz(a)anthracene (DMBA) or UVB exposure] and adult treatments (12-O-tetradecanoylphorbol-13-acetate or subacute daily UVB exposure or intermittent overexposure). Nevi occurred earliest, grew largest, and were most numerous in mice exposed to DMBA followed by intermittent UVB overexposure [effect of six minimal edemal doses (MED), 1 x /2 weeks > 4 MED 1 x /wk]. Neonatal UV exposure enhanced nevus induction but lost its effect after 200 days. The Xpa(-/-) mice proved exquisitely sensitive to UV-driven nevus induction, indicating the involvement of pyrimidine dimer DNA lesions, but Xpa(+/+) mice developed many more nevi (>40 per mouse) at high UV dosages not tolerated by Xpa(-/-) mice. Ink4a/Arf(-/-) mice developed most skin tumors faster, but surprisingly developed nevi slower than their heterozygous counterparts especially after neonatal UV exposure. Despite raising >1,600 nevi, only six melanomas arose in our experiments with Ink4a/Arf knockout mice (five of which in Xpa(+/+) mice at high UV dosages). In contrast to human nevi, these nevi lacked hotspot mutations in Braf or Ras genes, possibly explaining the lack of malignant progression in the Ink4a/Arf(-/-) mice. Hence, although our experiments did not effectively emulate human melanoma, they provided clear evidence that intermittent UV overexposure strongly stimulates and the Ink4a/Arf(-/-) genotype may actually impair nevus development.


Assuntos
Cocarcinogênese , Inibidor p16 de Quinase Dependente de Ciclina/genética , Neoplasias Induzidas por Radiação/etiologia , Nevo/etiologia , Neoplasias Cutâneas/etiologia , Proteína Supressora de Tumor p14ARF/genética , Proteína de Xeroderma Pigmentoso Grupo A/genética , 9,10-Dimetil-1,2-benzantraceno , Animais , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/genética , Inibidor p16 de Quinase Dependente de Ciclina/deficiência , Melanoma Experimental/etiologia , Melanoma Experimental/genética , Camundongos , Camundongos Knockout , Neoplasias Induzidas por Radiação/induzido quimicamente , Neoplasias Induzidas por Radiação/genética , Nevo/genética , Sarcoma/etiologia , Sarcoma/genética , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/genética , Proteína Supressora de Tumor p14ARF/deficiência , Raios Ultravioleta
7.
Public Health Genomics ; 21(1-2): 1-17, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30145589

RESUMO

The expansion of European small and medium-sized enterprises (SMEs) into the healthcare innovation arena suggests that this should be an important EU policy priority that can significantly benefit the economy, society and citizens, including patients. Deepening and widening of Europe's SMEs' growth and activities is part of the EU objectives as set out by the European Commission in its Communications "Small Business Act" for Europe [1] and "Small Business, Big World" [2]. However, innovative healthcare SMEs have struggled to get traction despite the sector being worth more than EUR 250 billion. The 1991 Maastricht Treaty gave the Union new competences in public health and more scope for cross-border cooperation in this area [3]. Nevertheless, health initiatives here have tripped over each other, due to the fact that the delivery of healthcare is a national competence [4]. As such, EU healthcare-driven policy has never truly found its footing as a singular policy area despite the fact that a tenth of the EU's GDP is spent on healthcare and more than 17 million people are employed in Europe in this sector [5]. Taking into account the necessity of bringing innovation into healthcare, and the willingness of SMEs to undertake the risk to be at the forefront of it, there is a need for a renewed effort to support SMEs so as to provide solutions for citizens and patients throughout the bloc in different healthcare settings [6]. This policy paper brings together two separate strands of analysis: firstly, a policy review of the main challenges and opportunities; secondly, a proposal for policy recommendations.


Assuntos
Atenção à Saúde/tendências , Setor de Assistência à Saúde/tendências , Política de Saúde , Atenção à Saúde/organização & administração , Europa (Continente) , União Europeia , Setor de Assistência à Saúde/organização & administração , Humanos , Inovação Organizacional
8.
BMC Microbiol ; 7: 88, 2007 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-17935610

RESUMO

BACKGROUND: Susceptibility to Bordetella pertussis infection varies widely. These differences can partly be explained by genetic host factors. HcB-28 mice are more resistant to B. pertussis infection than C3H mice, which could partially be ascribed to the B. pertussis susceptibility locus-1 (Bps1) on chromosome 12. The presence of C57BL/10 genome on this locus instead of C3H genome resulted in a decreased number of bacteria in the lung. To further elucidate the role of host genetic factors, in particular in the Bps1 locus, in B. pertussis infection, and to identify candidate genes within in this region, we compared expression profiles in the lungs of the C3H and HcB-28 mouse strains following B. pertussis inoculation. Twelve and a half percent of the genomes of these mice are from a different genetic background. RESULTS: Upon B. pertussis inoculation 2,353 genes were differentially expressed in the lungs of both mouse strains. Two hundred and six genes were differentially expressed between the two mouse strains, but, remarkably, none of these were up- or down-regulated upon B. pertussis infection. Of these 206 genes, 17 were located in the Bps1 region. Eight of these genes, which showed a strong difference in gene expression between the two mouse strains, map to the immunoglobulin heavy chain complex (Igh). CONCLUSION: Gene expression changes upon B. pertussis infection are highly identical between the two mouse strains despite the differences in the course of B. pertussis infection. Because the genes that were differentially regulated between the mouse strains only showed differences in expression before infection, it appears likely that such intrinsic differences in gene regulation are involved in determining differences in susceptibility to B. pertussis infection. Alternatively, such genetic differences in susceptibility may be explained by genes that are not differentially regulated between these two mouse strains. Genes in the Igh complex, among which Igh-1a/b, are likely candidates to explain differences in susceptibility to B. pertussis. Thus, by microarray analysis we significantly reduced the number of candidate susceptibility genes within the Bps1 locus. Further work should establish the role of the Igh complex in B. pertussis infection.


Assuntos
Bordetella pertussis/patogenicidade , Perfilação da Expressão Gênica , Cadeias Pesadas de Imunoglobulinas/metabolismo , Proteínas/metabolismo , Coqueluche/genética , Coqueluche/imunologia , Animais , Suscetibilidade a Doenças , Feminino , Regulação da Expressão Gênica , Cadeias Pesadas de Imunoglobulinas/genética , Pulmão/patologia , Camundongos , Camundongos Congênicos , Camundongos Endogâmicos C3H , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Proteínas/genética , Aumento de Peso , Redução de Peso , Coqueluche/microbiologia , Coqueluche/patologia
9.
Front Public Health ; 5: 53, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28377917

RESUMO

PURPOSE: Newborn bloodspot screening (NBS) programs have expanded significantly in the past years and are expected to expand further with the emergence of genetic technologies. Historically, NBS expansion has often occurred following ad hoc consideration of conditions, instead of a structured and transparent approach. In this review, we explore issues pertinent to NBS policy making, through the lens of the policy cycle: (a) agenda setting, (b) policy advice, (c) policy decision, (d) implementation, and (e) evaluation. METHODS: A literature search was conducted to gather information on the elements specific to NBS and its policy making process. RESULTS: The review highlighted two approaches to nominate a condition: a structured approach through horizon scanning; and an ad hoc process. For assessment of a condition, there was unanimous support for a robust process based on criteria. While the need to assess harms and benefits was a repeated theme in the articles, there is no agreed-upon threshold for benefit in decision-making. Furthermore, the literature was consistent in its recommendation for an overarching, independent, multidisciplinary group providing recommendations to government. An implementation plan focusing on the different levels on which NBS operates and the information needed on each level is essential for successful implementation. Continuously monitoring, and improving a program is vital, particularly following the implementation of screening for a new condition. An advisory committee could advise on implementation, development, review, modification, and cessation of (parts of) NBS. CONCLUSION: The results highlight that there are a wave of issues facing NBS programs that policy makers must take into account when developing policy processes. What conditions to screen, and the technologies used in NBS, are both up for debate.

10.
DNA Repair (Amst) ; 4(1): 81-9, 2005 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-15533840

RESUMO

Nucleotide excision repair (NER), cell cycle regulation and apoptosis are major defence mechanisms against the carcinogenic effects of UVB radiation. NER eliminates UVB-induced DNA photolesions via two subpathways: global genome repair (GGR) and transcription-coupled repair (TCR). In a previous study, we found UVB-induced accumulation of tetraploid (4N) keratinocytes in the epidermis of Xpc(-/-) mice (no GGR), but not in Xpa(-/-) (no TCR and no GGR) or in wild-type (WT) mice. We inferred that this arrest in Xpc(-/-) mice is caused by erroneous replication past photolesions, leading to 'compound lesions' known to be recognised by mismatch repair (MMR). MMR-induced futile cycles of breakage and resynthesis at sites of compound lesions may then sustain a cell cycle arrest. The present experiments with Xpc(-/-)Msh2(-/-) mice and derived keratinocytes show that the MMR protein Msh2 indeed plays a role in the generation of the UVB-induced arrested cells: a Msh2-deficiency lowered significantly the percentage of arrested cells in vivo (40-50%) and in vitro (30-40%). Analysis of calyculin A (CA)-induced premature chromosome condensation (PCC) of cultured Xpc(-/-) keratinocytes showed that the delayed arrest occurred in late S phase rather than in G(2)-phase. Taken together, the results indicate that in mouse epidermis and cultured keratinocytes, the MMR protein Msh2 plays a role in the UVB-induced S-phase arrest. This indicates that MMR plays a role in the UVB-induced S-phase arrest. Alternatively, Msh2 may have a more direct signalling function.


Assuntos
Pareamento Incorreto de Bases/genética , Ciclo Celular/efeitos da radiação , Reparo do DNA , Proteínas de Ligação a DNA/genética , Proteínas Proto-Oncogênicas/genética , Animais , Bromodesoxiuridina , Ciclo Celular/genética , Citometria de Fluxo , Queratinócitos/fisiologia , Toxinas Marinhas , Camundongos , Camundongos Mutantes , Proteína 2 Homóloga a MutS , Oxazóis , Raios Ultravioleta
11.
Per Med ; 13(4): 381-393, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29749811

RESUMO

Advances in the fields of genomic sciences have given rise to personalized medicine. This new paradigm draws upon a patient's genetic and metabolic makeup in order to tailor diagnostics and treatment. Personalized medicine holds remarkable promises to improve prevention and management of chronic diseases of global relevance, such as Type 2 diabetes mellitus (T2DM). This review article aims at summarizing the evidence from genome-based sciences on T2DM risk and management in different populations and in the Global Health context. Opinions from leading experts in the field were also included. Based on these findings, strengths and weaknesses of personalized approach to T2DM in a global context are delineated. Implications for future research and implementation on that subject are discussed.

12.
Eur J Hum Genet ; 24(3): 361-6, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26036860

RESUMO

This study explored individuals' preferences for genetic testing for colorectal cancer (CRC) in a screening situation and their willingness to participate in genetic testing for Lynch syndrome, familial adenomatous polyposis (FAP), and familial colorectal cancer (FCC). For that purpose, 532 respondents aged 55-65 years completed a Discrete Choice Experiment. Using panel latent class models, the preferences for two screening situation characteristics (the probability of being genetically predisposed and the probability of developing CRC) and screening test characteristics (the frequency of preventive colonoscopies and CRC survival) were estimated. Based on these preferences, respondents' willingness to participate in the three screening initiatives was estimated. Lower-educated respondents and respondents who express serious anxiety and worries found colonoscopy frequency and the probability of developing CRC relatively more important and survival relatively less important compared with higher-educated respondents and respondents who express no anxiety and worries. These differences in preferences resulted in opposite preferences for participation in FCC and FAP screening. In conclusion, the general population is willing to participate in genetic screening for CRC. If individuals are suspected of genetic or familial CRC, they should at least be informed about their increased risk of being genetically predisposed and about the importance of participating in all preventive follow-up colonoscopies in order to maximize survival.


Assuntos
Comportamento de Escolha , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Detecção Precoce de Câncer , Testes Genéticos , Polipose Adenomatosa do Colo/genética , Neoplasias Colorretais Hereditárias sem Polipose/genética , Demografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Pathog Dis ; 74(3)2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26867646

RESUMO

Chlamydia trachomatis is the most common sexually transmitted bacterium worldwide. Its often asymptomatic course of infection increases chances of transmission, and increases risk of late complications. Genetic variations in the host immune system are known to impact the course of infections. Recent studies have shown a positive impact of vitamin D on the regulation of the immune system. This study assesses the impact of eight polymorphisms in five genes [VDR (rs1544410 G > A, rs2228570 C > T), CYP27B1 (rs10877012 G > T), DHCR7 (rs7944926 G > A, rs3829251 G > A), GC (rs3755967) and CYP2R1 (rs10741657 G > A, rs2060793 G > A)] on susceptibility to Chlamydia infections in humans. These polymorphisms could influence protein expression or function, and thus influence the immune system. Samples of women visiting the STD outpatient clinic in South Limburg were genotyped using the Roche Lightcycler 480. In this study, we did not observe statistically significant differences between the genotype distributions of these polymorphisms in women with or without a Chlamydia infection. This suggests that VDR, CYP27B1, DHCR7, GC and CYP2R1 do not affect the susceptibility to Chlamydia infections. However, due to its pleiotropic nature in the immune system a role for the vitamin D pathway may not be excluded from the whole clinical course of Chlamydia infections (e.g. late complications), and further research is required.


Assuntos
Infecções por Chlamydia/patologia , Chlamydia trachomatis/patogenicidade , Predisposição Genética para Doença/genética , Vitamina D/metabolismo , 25-Hidroxivitamina D3 1-alfa-Hidroxilase/genética , Estudos de Casos e Controles , Colestanotriol 26-Mono-Oxigenase/genética , Família 2 do Citocromo P450 , Feminino , Genótipo , Humanos , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Polimorfismo de Nucleotídeo Único/genética , Receptores de Calcitriol/genética
14.
Photochem Photobiol ; 81(1): 52-64, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15535734

RESUMO

The genetic changes and corruption of kinase activity in melanomas appear to revolve around a central axis: mitogenic signaling along the RAS pathway down to transcription regulation by pRB. Epidemiological studies point to the importance of ultraviolet (UV) radiation in the etiology of melanoma, but where and how UV radiation is targeted to contribute to the oncogenic signaling remains obscure. Animal models of melanoma genesis could serve to clarify this issue, but many of these models are not responsive to UV exposure. Most interesting advances have been made by using transgenic mice that carry genetic defects that are known to be relevant to human melanoma: specifically, dysfunction in the tumor suppressive action of p16INK4a or a receptor tyrosine kinase/RAS pathway, that is constitutively activated in melanocytes. The latter types of mice appear to be most responsive to (neonatal) UV exposure. Whether this is due to a general increase in target cells by melanocytosis and a paucity or complete lack of pigment, or a possible UV-induced response of the promoter-enhancer of the transgene or a genuinely independent and additional genetic alteration caused by UV exposure needs to be established. Importantly, the full effect of UV radiation needs to be ascertained in mice with different pigmentation by varying the wavelengths, UV-B versus UV-A1, and the exposure schedules, i.e. neonatal versus adult and chronic versus intermittent overexposure. Intermittent UV-B overexposure deserves special attention because it most strongly evokes proliferative responses in melanocytes.


Assuntos
Modelos Animais de Doenças , Melanoma/genética , Neoplasias Cutâneas/genética , Raios Ultravioleta , Animais , Predisposição Genética para Doença , Camundongos , Camundongos Transgênicos , Transdução de Sinais
15.
Mutat Res ; 571(1-2): 81-90, 2005 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-15748640

RESUMO

Exposure to (solar) UVB radiation gives rise to mutations in the p53 tumor suppressor gene that appear to contribute to the earliest steps in the molecular cascade towards human and murine skin cancer. To examine in more detail the role of p53, we studied UVB-induced carcinogenesis in hairless p53 knock-out mice. The early onset of lymphomas as well as early wasting of mice interfered with the development of skin tumors in p53 null-mice. The induction of skin tumors in the hairless p53+/- mice was accomplished by daily exposure to two different UV-doses of approximately 450 J/m2 and 900 J/m2 from F40 lamps corresponding to a fraction of about 0.4 and 0.8 of the minimal edemal dose. Marked differences in skin carcinogenesis were observed between the p53+/- mice and their wild type littermates. Firstly, at 900 J/m2, tumors developed significantly faster in the heterozygotes than in wild types, whereas at 450 J/m2 there was hardly any difference, suggesting that only at higher damage levels loss of one functional p53 allele is important. Secondly, a large portion (25%) of skin tumors in the heterozygotes were of a more malignant, poorly differentiated variety of squamous cell carcinomas, i.e. spindle cell carcinomas, a tumor type that was rarely observed in daily UV exposed wild type hairless mice. Thirdly, the p53 mutation spectrum in skin tumors in heterozygotes is quite different from that in wild types. Together these results support the notion that a point mutation in the p53 gene impacts skin carcinogenesis quite differently than allelic loss: the former is generally selected for in early stages of skin tumors in wild type mice, whereas the latter enhances tumor development only at high exposure levels (where apoptosis becomes more prevalent) and appears to increase progression (to a higher grade of malignancy) of skin tumors.


Assuntos
Genes p53 , Neoplasias Induzidas por Radiação/etiologia , Neoplasias Cutâneas/etiologia , Raios Ultravioleta , Animais , Sequência de Bases , Primers do DNA , Relação Dose-Resposta a Droga , Imuno-Histoquímica , Camundongos , Camundongos Pelados , Camundongos Knockout , Mutação , Neoplasias Induzidas por Radiação/genética , Neoplasias Cutâneas/genética
16.
Mutat Res ; 577(1-2): 170-8, 2005 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-15949822

RESUMO

UV-induced cyclobutane pyrimidine dimers (CPDs) are removed with accelerated speed from the transcribed strand of expressed genes in cultured mammalian cells by a process called transcription-coupled repair (TCR). It has been previously shown that this phenomenon has consequences for the molecular nature of the mutations induced by UV-light. Here, we review these data and show that TCR has not only a clear impact on UV-induced mutations in cultured mammalian cells but also on genes involved in tumor formation in the skin of UV-exposed mice. Mutations observed in the p53 gene in UV-induced squamous cell carcinoma are predominantly found at sites of dipyrimidines in the non-transcribed strand. In contrast, in UVC-irradiated Csb(-/-) Chinese hamster cells and in UVB-induced tumors in the Csb(-/-) mouse, almost all mutations are at positions of dipyrimidine sites in the transcribed strand of the mutated gene. Csb(-/-) mice appear to be susceptible to UVB-induced skin cancer in contrast to the human CSB patients. We speculate that the UVB-induced cancer susceptibility of Csb(-/-) mice is related to the absence of TCR as well as to a lack of a compensating global genome repair system for CPDs in mice.


Assuntos
Reparo do DNA , Mutagênese , Neoplasias Cutâneas/genética , Transcrição Gênica , Raios Ultravioleta , Animais , Células Cultivadas , Camundongos
17.
J Natl Cancer Inst ; 106(5)2014 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-24718872

RESUMO

We prospectively evaluated fat intake as predictor of developing breast cancer (BC) subtypes defined by estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor 2 receptor (HER2), in a large (n = 337327) heterogeneous cohort of women, with 10062 BC case patients after 11.5 years, estimating BC hazard ratios (HRs) by Cox proportional hazard modeling. High total and saturated fat were associated with greater risk of ER(+)PR(+) disease (HR = 1.20, 95% confidence interval [CI] = 1.00 to 1.45; HR = 1.28, 95% CI = 1.09 to 1.52; highest vs lowest quintiles) but not ER(-)PR(-) disease. High saturated fat was statistically significantly associated with greater risk of HER2(-) disease. High saturated fat intake particularly increases risk of receptor-positive disease, suggesting saturated fat involvement in the etiology of this BC subtype.


Assuntos
Neoplasias da Mama/epidemiologia , Dieta Hiperlipídica/estatística & dados numéricos , Gorduras na Dieta/administração & dosagem , Neoplasias da Mama/etiologia , Neoplasias da Mama/metabolismo , Estudos de Coortes , Feminino , Humanos , Incidência , Análise Multivariada , Modelos de Riscos Proporcionais , Receptor ErbB-2/biossíntese , Receptores de Estrogênio/biossíntese , Receptores de Progesterona/biossíntese
18.
Eur J Pharmacol ; 668 Suppl 1: S2-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21816140

RESUMO

It is increasingly recognized that most chronic diseases of concern today are multifactorial in origin. To combat such diseases and adverse health conditions, a treatment approach where medicines and nutrition complement each other may prove to be the most successful. Within nutrition, apart from (disease-related) dietetic regimes, an increasing number of functional foods and dietary supplements, each with their own health claim, are marketed. These food items are considered to be positioned between traditional foods and medicines at the so-called 'Pharma-Nutrition Interface'. This paper encompasses aspects related to the regulatory framework and health claims of functional foods and dietary supplements. The use of functional foods or dietary supplements may offer opportunities to reduce health risk factors and risk of diseases, both as monotherapy and in combination with prescription drugs. Nevertheless, the potential caveats of these products should not be overlooked. These caveats include the increased risk for food-drug interactions due to the elevated amounts of specific functional ingredients in the diet, and the stimulation of self-medication potentially resulting in lower adherence to drug therapy. Health technology assessments should be used more to compare the cost-effectiveness and benefit-risk ratios of drugs, functional foods and dietary supplements, and to evaluate the added value of functional foods or dietary supplements to drug therapy.


Assuntos
Suplementos Nutricionais , Alimento Funcional , Medicina , Ciências da Nutrição , Tecnologia Biomédica , Suplementos Nutricionais/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Alimento Funcional/efeitos adversos , Humanos
19.
Eur J Pharmacol ; 668 Suppl 1: S91-100, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21816151

RESUMO

The present modelling study aimed to evaluate if and by how much functional foods containing phytosterols/-stanols add to the benefits of statins in the prevention of cardiovascular disease in terms of cost-effectiveness. Long-term health effects, measured as quality-adjusted life-years gained, and costs for scenarios with additional phytosterol/-stanol use were compared to scenarios without extra use. Phytosterols/-stanols were given only to persons who were eligible for use according to their 10-year absolute risk of fatal cardiovascular disease (SCORE-risk). Intake levels and discontinuation rates as observed in daily practice were included in the model. Two situations were compared: 1) A real-life situation in which persons at high SCORE-risk were identified through clinical case-finding and, 2) A theoretical maximum situation where universal screening was implemented resulting in known SCORE-risks for the whole Dutch population aged 35-75 years (8.4 million people). Sensitivity analyses were performed for variations in the cholesterol-lowering effect and intake level of phytosterols/-stanols, indirect health care costs, time horizon and discount rates. At the model's start year, a total of 1.0 (real-life situation) to 3.3 (maximum situation) million persons qualified for phytosterol/-stanol use based on their SCORE-risk (both statin users and statin non-users). Over the model's time horizon, this resulted in a gain of 2700 to 16,300 quality-adjusted life-years, and yielded cost-effectiveness ratios that ranged between €92,000 and €203,000 per quality-adjusted life-year. This simulation study showed that the cost-effectiveness of phytosterols/-stanols as monotherapy and as add-on to statins is above thresholds for cost-effectiveness, generally ranging between €20,000 and €50,000, and is thus a non-cost-effective strategy to reduce cardiovascular disease.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Alimento Funcional/economia , Alimento Funcional/estatística & dados numéricos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Fitosteróis/uso terapêutico , Doenças Cardiovasculares/dietoterapia , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/economia , Análise Custo-Benefício , Alimento Funcional/análise , Custos de Cuidados de Saúde , Humanos , Fitosteróis/farmacologia
20.
Cancer Epidemiol Biomarkers Prev ; 20(12): 2532-40, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21994406

RESUMO

BACKGROUND: Epidemiologic data and animal models suggest that, despite the predominant role of human papillomavirus infection, sex steroid hormones are also involved in the etiology of invasive cervical carcinoma (ICC). METHODS: Ninety-nine ICC cases, 121 cervical intraepithelial neoplasia grade 3 (CIN3) cases and 2 control women matched with each case for center, age, menopausal status and blood collection-related variables, were identified in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. Circulating levels of testosterone (T) and estradiol (E(2)); dehydroepiandrosterone sulfate (DHEAS); progesterone (premenopausal women); and sex hormone-binding globulin (SHBG) were measured using immunoassays. Levels of free (f) T and E(2) were calculated from absolute concentrations of T, E(2), and SHBG. Odds ratios (ORs) and 95% confidence intervals (CI) were computed using regularized conditional logistic regression. RESULTS: Among premenopausal women, associations with ICC were observed for fT (OR for highest vs. lowest tertile = 5.16, 95% CI, 1.50-20.1). SHBG level was associated with a significant downward trend in ICC risk. T, E(2), fE(2), and DHEAS showed nonsignificant positive association with ICC. Progesterone was uninfluential. Among postmenopausal women, associations with ICC were found for T (OR = 3.14; 95% CI, 1.21-9.37), whereas E(2) and fT showed nonsignificant positive association. SHBG level was unrelated to ICC risk in postmenopausal women. No associations between any hormone and CIN3 were detected in either pre- or postmenopausal women. CONCLUSIONS: Our findings suggest for the first time that T and possibly E(2) may be involved in the etiology of ICC. IMPACT: The responsiveness of cervical tumors to hormone modulators is worth exploring.


Assuntos
Biomarcadores Tumorais/sangue , Hormônios Esteroides Gonadais/sangue , Neoplasias do Colo do Útero/sangue , Adulto , Idoso , Estudos de Casos e Controles , Estradiol/sangue , Europa (Continente)/epidemiologia , Feminino , Humanos , Pessoa de Meia-Idade , Progesterona/sangue , Estudos Prospectivos , Fatores de Risco , Testosterona/sangue , Neoplasias do Colo do Útero/epidemiologia
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