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1.
BMC Public Health ; 23(1): 2416, 2023 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-38053057

RESUMO

A cornerstone of asthma management is maintaining physical activity (PA), but this may lead to increased exposure to, and deeper inhalation of, pollutants. Furthermore, children and adolescents may be more susceptible to the deleterious impacts of such exposures. Despite the recent air quality campaigns and media coverage surrounding the dangers of air pollution to respiratory health, few target children and their understanding of such issues.Using semi structured interviews, understanding of PA, air pollution and their interaction was explored with 25 youth aged 7-17 years. Utilising NVIVO 12 software, an atheoretical, inductive thematic analysis was conducted to identify key themes which were subsequently presented as pen profiles with the number of common responses within a theme indicative of its strength.The majority (88%) of youth's indicated traffic-related air pollution and global manufacturing as key sources of air pollution. Whilst all youths were aware of outdoor pollution, only 52% were aware of indoor air pollutants, of which 62% had asthma. Despite some uncertainty, all youths described pollution in a negative fashion, with 52% linking air pollution to undesirable effects on health, specifically respiratory health. PA in a polluted area was thought to be more dangerous than beneficial by 44%, although 24% suggested the benefits of PA would outweigh any detriment from pollution.Youth are aware of, and potentially compensate for, the interaction between air pollution and PA. Strategies are needed to allow youth to make more informed decisions regarding how to promote PA whilst minimising exposure to air pollution.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Asma , Poluentes Ambientais , Adolescente , Criança , Humanos , Asma/epidemiologia , Asma/etiologia , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Exercício Físico , Exposição Ambiental/efeitos adversos
2.
Nucleic Acids Res ; 43(19): 9133-46, 2015 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-26400171

RESUMO

The mutational pattern for the TP53 tumour suppressor gene in lung tumours differs to other cancer types by having a higher frequency of G:C>T:A transversions. The aetiology of this differing mutation pattern is still unknown. Benzo[a]pyrene,diol epoxide (BPDE) is a potent cigarette smoke carcinogen that forms guanine adducts at TP53 CpG mutation hotspot sites including codons 157, 158, 245, 248 and 273. We performed molecular modelling of BPDE-adducted TP53 duplex sequences to determine the degree of local distortion caused by adducts which could influence the ability of nucleotide excision repair. We show that BPDE adducted codon 157 has greater structural distortion than other TP53 G:C>T:A hotspot sites and that sequence context more distal to adjacent bases must influence local distortion. Using TP53 trinucleotide mutation signatures for lung cancer in smokers and non-smokers we further show that codons 157 and 273 have the highest mutation probability in smokers. Combining this information with adduct structural data we predict that G:C>T:A mutations at codon 157 in lung tumours of smokers are predominantly caused by BPDE. Our results provide insight into how different DNA sequence contexts show variability in DNA distortion at mutagen adduct sites that could compromise DNA repair at well characterized cancer related mutation hotspots.


Assuntos
Benzo(a)pireno/química , Carcinógenos/química , Adutos de DNA/química , Dano ao DNA , Genes p53 , Neoplasias Pulmonares/genética , Mutação , 7,8-Di-Hidro-7,8-Di-Hidroxibenzo(a)pireno 9,10-óxido/química , Sequência de Bases , Códon , DNA/química , Humanos , Ligação de Hidrogênio , Simulação de Dinâmica Molecular , Fumar
3.
Mutagenesis ; 31(3): 323-8, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26208916

RESUMO

Assessment of genetic toxicity and/or carcinogenic activity is an essential element of chemical screening programs employed to protect human health. Dose-response and gene mutation data are frequently analysed by industry, academia and governmental agencies for regulatory evaluations and decision making. Over the years, a number of efforts at different institutions have led to the creation and curation of databases to house genetic toxicology data, largely, with the aim of providing public access to facilitate research and regulatory assessments. This article provides a brief introduction to a new genetic toxicology portal called Mutation Analysis Informatics Tools (MutAIT) (www.mutait.org) that provides easy access to two of the largest genetic toxicology databases, the Mammalian Gene Mutation Database (MGMD) and TransgenicDB. TransgenicDB is a comprehensive collection of transgenic rodent mutation data initially compiled and collated by Health Canada. The updated MGMD contains approximately 50 000 individual mutation spectral records from the published literature. The portal not only gives access to an enormous quantity of genetic toxicology data, but also provides statistical tools for dose-response analysis and calculation of benchmark dose. Two important R packages for dose-response analysis are provided as web-distributed applications with user-friendly graphical interfaces. The 'drsmooth' package performs dose-response shape analysis and determines various points of departure (PoD) metrics and the 'PROAST' package provides algorithms for dose-response modelling. The MutAIT statistical tools, which are currently being enhanced, provide users with an efficient and comprehensive platform to conduct quantitative dose-response analyses and determine PoD values that can then be used to calculate human exposure limits or margins of exposure.


Assuntos
Análise Mutacional de DNA/métodos , Bases de Dados de Ácidos Nucleicos , Mutagênicos/toxicidade , Mutação , Software , Toxicologia/métodos , Animais , Carcinógenos/toxicidade , Biologia Computacional/métodos , DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Genética , Humanos , Masculino , Camundongos , Modelos Genéticos , Primatas/genética , Ratos
4.
Mol Pharm ; 13(3): 863-72, 2016 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-26833139

RESUMO

The host- and bacteria-derived extracellular polysaccharide coating of the lung is a considerable challenge in chronic respiratory disease and is a powerful barrier to effective drug delivery. A low molecular weight 12-15-mer alginate oligosaccharide (OligoG CF-5/20), derived from plant biopolymers, was shown to modulate the polyanionic components of this coating. Molecular modeling and Fourier transform infrared spectroscopy demonstrated binding between OligoG CF-5/20 and respiratory mucins. Ex vivo studies showed binding induced alterations in mucin surface charge and porosity of the three-dimensional mucin networks in cystic fibrosis (CF) sputum. Human studies showed that OligoG CF-5/20 is safe for inhalation in CF patients with effective lung deposition and modifies the viscoelasticity of CF-sputum. OligoG CF-5/20 is the first inhaled polymer therapy, represents a novel mechanism of action and therapeutic approach for the treatment of chronic respiratory disease, and is currently in Phase IIb clinical trials for the treatment of CF.


Assuntos
Alginatos/química , Fibrose Cística/tratamento farmacológico , Mucinas/química , Muco/química , Oligossacarídeos/química , Polímeros/farmacologia , Adolescente , Adulto , Alginatos/metabolismo , Animais , Doença Crônica , Ensaios Clínicos Fase I como Assunto , Feminino , Ácido Glucurônico/química , Ácido Glucurônico/metabolismo , Ácidos Hexurônicos/química , Ácidos Hexurônicos/metabolismo , Humanos , Masculino , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Mucinas/metabolismo , Muco/metabolismo , Oligossacarídeos/metabolismo , Polímeros/química , Ratos , Ratos Sprague-Dawley , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier , Escarro/química , Suínos , Adulto Jovem
5.
Exp Mol Pathol ; 95(2): 220-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23933194

RESUMO

Prostate cancer is the second most frequently diagnosed cancer worldwide and is the sixth leading cause of cancer deaths in men, yet it varies greatly in its aggressiveness. Currently, it is not possible to adequately differentiate between patients whose tumors will remain indolent and those patients whose disease will progress, resulting in unnecessary aggressive treatment. Consequently, there is an urgent need to identify markers of prostate cancer progression, invasiveness and metastasis to more accurately predict prognosis. The aim of this study was to assess the ability of key epithelial-to-mesenchymal transition molecules in identifying prostate cancer patients who are likely to develop aggressive tumors. Using 215 archival patient tissue samples, immunohistochemistry was applied to examine the expression and sub-cellular localization of E-Cadherin, Snail, Slug, Twist, Vimentin, BMP-2 and BMP-7. Of the seven markers assessed, a significantly increased expression of Snail protein was observed within the nucleus of prostate cancer cells and was strongly associated with increasing Gleason score and clinical stage. In addition, loss of E-Cadherin expression at the cellular membrane of prostate cancer cells was also significantly associated with increasing Gleason score, clinical stage, and additionally, a reduction in survival.


Assuntos
Biomarcadores Tumorais/análise , Transição Epitelial-Mesenquimal , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Idoso , Idoso de 80 Anos ou mais , Caderinas/análise , Caderinas/biossíntese , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Prognóstico , Fatores de Transcrição da Família Snail , Fatores de Transcrição/análise , Fatores de Transcrição/biossíntese
6.
BMC Chem ; 15(1): 51, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34521464

RESUMO

BACKGROUND: Local sequence context is known to have an impact on the mutational pattern seen in cancer. The RAS genes and a smoking carcinogen, Benzo[a]pyrene diol epoxide (BPDE), have been utilised to explore these context effects. BPDE is known to form an adduct at the guanines in a number of RAS gene sites, KRAS codons 12, 13 and 14, NRAS codon 12, and HRAS codons 12 and 14. RESULTS: Molecular modelling techniques, along with multivariate analysis, have been utilised to determine the sequence influenced differences between BPDE-adducted RAS gene sequences as well as the local distortion caused by the adducts. CONCLUSIONS: We conclude that G:C > T:A mutations at KRAS codon 12 in the tumours of lung cancer patients (who smoke), proposed to be predominantly caused by BPDE, are due to the effect of the interaction methyl group at the C5 position of the thymine base in the KRAS sequence with the BPDE carcinogen investigated causing increased distortion. We further suggest methylated cytosine would have a similar effect, showing the importance of methylation in cancer development.

7.
BMC Cancer ; 10: 640, 2010 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-21092279

RESUMO

BACKGROUND: Survival time for lung cancer is poor with over 90% of patients dying within five years of diagnosis primarily due to detection at late stage. The main objective of this study was to evaluate Fourier transform infrared spectroscopy (FTIR) as a high throughput and cost effective method for identifying biochemical changes in sputum as biomarkers for detection of lung cancer. METHODS: Sputum was collected from 25 lung cancer patients in the Medlung observational study and 25 healthy controls. FTIR spectra were generated from sputum cell pellets using infrared wavenumbers within the 1800 to 950 cm-1 "fingerprint" region. RESULTS: A panel of 92 infrared wavenumbers had absorbances significantly different between cancer and normal sputum spectra and were associated with putative changes in protein, nucleic acid and glycogen levels in tumours. Five prominent significant wavenumbers at 964 cm-1, 1024 cm-1, 1411 cm-1, 1577 cm-1 and 1656 cm-1 separated cancer spectra from normal spectra into two distinct groups using multivariate analysis (group 1: 100% cancer cases; group 2: 92% normal cases). Principal components analysis revealed that these wavenumbers were also able to distinguish lung cancer patients who had previously been diagnosed with breast cancer. No patterns of spectra groupings were associated with inflammation or other diseases of the airways. CONCLUSIONS: Our results suggest that FTIR applied to sputum might have high sensitivity and specificity in diagnosing lung cancer with potential as a non-invasive, cost-effective and high-throughput method for screening. TRIAL REGISTRATION: ClinicalTrials.gov: NCT00899262.


Assuntos
Biomarcadores Tumorais/análise , Ensaios de Triagem em Larga Escala , Neoplasias Pulmonares/diagnóstico , Programas de Rastreamento/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Escarro/química , Idoso , Estudos de Casos e Controles , Ensaios Clínicos como Assunto , Feminino , Humanos , Neoplasias Pulmonares/química , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Análise de Componente Principal , Sensibilidade e Especificidade , País de Gales
8.
Biol Cell ; 102(2): 133-43, 2009 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-20001971

RESUMO

AFM (atomic force microscopy) analysis, both of fixed cells, and live cells in physiological environments, is set to offer a step change in the research of cellular function. With the ability to map cell topography and morphology, provide structural details of surface proteins and their expression patterns and to detect pico-Newton force interactions, AFM represents an exciting addition to the arsenal of the cell biologist. With the explosion of new applications, and the advent of combined instrumentation such as AFM-confocal systems, the biological application of AFM has come of age. The use of AFM in the area of biomedical research has been proposed for some time, and is one where a significant impact could be made. Fixed cell analysis provides qualitative and quantitative subcellular and surface data capable of revealing new biomarkers in medical pathologies. Image height and contrast, surface roughness, fractal, volume and force analysis provide a platform for the multiparameter analysis of cell and protein functions. Here, we review the current status of AFM in the field and discuss the important contribution AFM is poised to make in the understanding of biological systems.


Assuntos
Técnicas Citológicas/métodos , Microscopia de Força Atômica/métodos , Animais , Tecnologia Biomédica , Sobrevivência Celular , Humanos , Microscopia de Força Atômica/instrumentação , Microscopia Eletrônica , Fixação de Tecidos
9.
Biol Cell ; 101(8): 481-93, 2009 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-19236310

RESUMO

BACKGROUND INFORMATION: The endometrial epithelial cell membrane is a key interface in female reproductive biology. Steroid hormones play a predominant role in cyclic changes which occur at this interface during the female menstrual cycle. Specific changes in the morphology of the endometrial epithelial cell surface become apparent with the epithelial transition that drives the switch from a non-receptive to receptive surface due to the action of progesterone on an oestrogen primed tissue. AFM (atomic force microscopy) allows the high-resolution characterization of the endometrial epithelial cell surface. Its contact probe mechanism enables a unique imaging method that requires little sample preparation, yielding topographical and morphological characterization. By stiffening the cell membrane, low concentrations of fixatives allow the surface detail of the cell to be resolved while preserving fine ultra-structural details for analysis. RESULTS: In the present study we use high resolution AFM analysis of endometrial epithelial cells to monitor the effect of progesterone on the nanoscale structure of the endometrial cell surface. High-resolution imaging reveals similar topographical nanoscale changes in both the Hec-1-A and Ishikawa model cell lines. Hec-1-B cells, used in the present study as a progesterone receptor negative control, however, exhibit a flattened cell surface morphology following progesterone treatment. Changes in average cell height and surface convolution correlate with increased surface roughness measurements, demonstrating alterations in molecular structure on the cell surface due to hormonal stimulation. CONCLUSIONS: Progesterone treatment induces changes to the cell surface as a result of nanoscale molecular modifications in response to external hormonal treatments. AFM provides the basis for the identification, visualization and quantification of these cell surface nanoscale changes. Together these findings demonstrate the utility of AFM for use in reproductive science and cancer biology where it could be applied in both in vitro analysis of protein structure-function relationships and clinical diagnosis.


Assuntos
Endométrio/química , Endométrio/metabolismo , Células Epiteliais/química , Células Epiteliais/metabolismo , Progesterona/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Endométrio/citologia , Células Epiteliais/citologia , Feminino , Humanos , Microscopia de Força Atômica
10.
Nucleic Acids Res ; 36(18): 5933-45, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18805907

RESUMO

Tamoxifen elevates the risk of endometrial tumours in women and alpha-(N(2)-deoxyguanosinyl)-tamoxifen adducts are reportedly present in endometrial tissue of patients undergoing therapy. Given the widespread use of tamoxifen there is considerable interest in elucidating the mechanisms underlying treatment-associated cancer. Using a combined experimental and multivariate statistical approach we have examined the mutagenicity and potential consequences of adduct formation by reactive intermediates in target uterine cells. pSP189 plasmid containing the supF gene was incubated with alpha-acetoxytamoxifen or 4-hydroxytamoxifen quinone methide (4-OHtamQM) to generate dG-N(2)-tamoxifen and dG-N(2)-4-hydroxytamoxifen, respectively. Plasmids were replicated in Ishikawa cells then screened in Escherichia coli. Treatment with both alpha-acetoxytamoxifen and 4-OHtamQM caused a dose-related increase in adduct levels, resulting in a damage-dependent increase in mutation frequency for alpha-acetoxytamoxifen; 4-OHtamQM had no apparent effect. Only alpha-acetoxytamoxifen generated statistically different supF mutation spectra relative to the spontaneous pattern, with most mutations being GC-->TA transversions. Application of the LwPy53 algorithm to the alpha-acetoxytamoxifen spectrum predicted strong GC-->TA hotspots at codons 244 and 273. These signature alterations do not correlate with current reports of the mutations observed in endometrial carcinomas from treated women, suggesting that dG-N(2)-tam adduct formation in the p53 gene is not a prerequisite for endometrial cancer initiation in women.


Assuntos
Adutos de DNA/análise , Endométrio/efeitos dos fármacos , Antagonistas de Estrogênios/toxicidade , Genes p53 , Mutagênese , Tamoxifeno/análogos & derivados , Algoritmos , Animais , Animais Geneticamente Modificados , Linhagem Celular , Análise Mutacional de DNA , Endométrio/química , Endométrio/citologia , Feminino , Genes Supressores , Humanos , RNA de Transferência/genética , Ratos , Tamoxifeno/análise , Tamoxifeno/toxicidade
11.
Ecancermedicalscience ; 12: 866, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30263057

RESUMO

The lung microbiome has been shown to reflect a range of pulmonary diseases-for example: asthma, chronic obstructive pulmonary disease (COPD) and cystic fibrosis. Studies have now begun to show microbiological changes in the lung that correlate with lung cancer (LC) which could provide new insights into lung carcinogenesis and new biomarkers for disease screening. Clinical studies have suggested that infections with tuberculosis or pneumonia increased the risk of LC possibly through inflammatory or immunological changes. These have now been superseded by genomic-based microbiome sequencing studies based on bronchoalveolar lavage, sputum or saliva samples. Although some discrepancies exist, many have suggested changes in particular bacterial genera in LC samples particularly, Granulicatella, Streptococcus and Veillonella. Granulicatella is of particular interest, as it appeared to show LC stage-specific increases in abundance. We propose that these microbial community changes are likely to reflect biochemical changes in the LC lung, linked to an increase in anaerobic environmental niches and altered pyridoxal/polyamine/nitrogenous metabolism to which Granulicatella could be particularly responsive. These are clearly preliminary observations and many more expansive studies are required to develop our understanding of the LC microbiome.

12.
Artigo em Inglês | MEDLINE | ID: mdl-29977590

RESUMO

Acquisition of a mucoid phenotype by Pseudomonas sp. in the lungs of cystic fibrosis (CF) patients, with subsequent over-production of extracellular polymeric substance (EPS), plays an important role in mediating the persistence of multi-drug resistant (MDR) infections. The ability of a low molecular weight (Mn = 3200 g mol-1) alginate oligomer (OligoG CF-5/20) to modify biofilm structure of mucoid Pseudomonas aeruginosa (NH57388A) was studied in vitro using scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM) with Texas Red (TxRd®)-labelled OligoG and EPS histochemical staining. Structural changes in treated biofilms were quantified using COMSTAT image-analysis software of CLSM z-stack images, and nanoparticle diffusion. Interactions between the oligomers, Ca2+ and DNA were studied using molecular dynamics (MD) simulations, Fourier transform infrared spectroscopy (FTIR) and isothermal titration calorimetry (ITC). Imaging demonstrated that OligoG treatment (≥0.5%) inhibited biofilm formation, revealing a significant reduction in both biomass and biofilm height (P < 0.05). TxRd®-labelled oligomers readily diffused into established (24 h) biofilms. OligoG treatment (≥2%) induced alterations in the EPS of established biofilms; significantly reducing the structural quantities of EPS polysaccharides, and extracellular (e)DNA (P < 0.05) with a corresponding increase in nanoparticle diffusion (P < 0.05) and antibiotic efficacy against established biofilms. ITC demonstrated an absence of rapid complex formation between DNA and OligoG and confirmed the interactions of OligoG with Ca2+ evident in FTIR and MD modelling. The ability of OligoG to diffuse into biofilms, potentiate antibiotic activity, disrupt DNA-Ca2+-DNA bridges and biofilm EPS matrix highlights its potential for the treatment of biofilm-related infections.

13.
PLoS One ; 12(5): e0177062, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28542458

RESUMO

Lung cancer (LC) is the most prevalent cancer worldwide, and responsible for over 1.3 million deaths each year. Currently, LC has a low five year survival rates relative to other cancers, and thus, novel methods to screen for and diagnose malignancies are necessary to improve patient outcomes. Here, we report on a pilot-sized study to evaluate the potential of the sputum microbiome as a source of non-invasive bacterial biomarkers for lung cancer status and stage. Spontaneous sputum samples were collected from ten patients referred with possible LC, of which four were eventually diagnosed with LC (LC+), and six had no LC after one year (LC-). Of the seven bacterial species found in all samples, Streptococcus viridans was significantly higher in LC+ samples. Seven further bacterial species were found only in LC-, and 16 were found only in samples from LC+. Additional taxonomic differences were identified in regards to significant fold changes between LC+ and LC-cases, with five species having significantly higher abundances in LC+, with Granulicatella adiacens showing the highest level of abundance change. Functional differences, evident through significant fold changes, included polyamine metabolism and iron siderophore receptors. G. adiacens abundance was correlated with six other bacterial species, namely Enterococcus sp. 130, Streptococcus intermedius, Escherichia coli, S. viridans, Acinetobacter junii, and Streptococcus sp. 6, in LC+ samples only, which could also be related to LC stage. Spontaneous sputum appears to be a viable source of bacterial biomarkers which may have utility as biomarkers for LC status and stage.


Assuntos
Bactérias/genética , Biomarcadores Tumorais/genética , Neoplasias Pulmonares/microbiologia , Microbiota/genética , Escarro/microbiologia , Idoso , Feminino , Humanos , Masculino , Metagenômica/métodos , Pessoa de Meia-Idade , Projetos Piloto
14.
Mutat Res ; 603(1): 15-26, 2006 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-16359913

RESUMO

The sensitivity of any mutational assay is determined by the level at which spontaneous mutations occur in the corresponding untreated controls. Establishing the type and frequency at which mutations occur naturally within a test system is essential if one is to draw scientifically sound conclusions regarding chemically induced mutations. Currently, mutation-spectra analysis is laborious and time-consuming. Thus, we have developed iMARS, a comprehensive mutation-spectrum analysis package that utilises routinely used methodologies and visualisation tools. To demonstrate the use and capabilities of iMARS, we have analysed the distribution, types and sequence context of spontaneous base substitutions derived from the cII gene mutation assay in transgenic animals. Analysis of spontaneous mutation spectra revealed variation both within and between the transgenic rodent test systems Big Blue Mouse, MutaMouse and Big Blue Rat. The most common spontaneous base substitutions were G:C-->A:T transitions and G:C-->T:A transversions. All Big Blue Mouse spectra were significantly different from each other by distribution and nearly all by mutation type, whereas the converse was true for the other test systems. Twenty-eight mutation hotspots were observed across all spectra generally occurring in CG, GA/TC, GG and GC dinucleotides. A mutation hotspot at nucleotide 212 occurred at a higher frequency in MutaMouse and Big Blue Rat. In addition, CG dinucleotides were the most mutable in all spectra except two Big Blue Mouse spectra. Thus, spontaneous base-substitution spectra showed more variation in distribution, type and sequence context in Big Blue Mouse relative to spectra derived from MutaMouse and Big Blue Rat. The results of our analysis provide a baseline reference for mutation studies utilising the cII gene in transgenic rodent models. The potential differences in spontaneous base-substitution spectra should be considered when making comparisons between these test systems. The ease at which iMARS has allowed us to carry out an exhaustive investigation to assess mutation distribution, mutation type, strand bias, target sequences and motifs, as well as predict mutation hotspots provides us with a valuable tool in helping to distinguish true chemically induced hotspots from background mutations and gives a true reflection of mutation frequency.


Assuntos
Análise Mutacional de DNA/estatística & dados numéricos , Software , Animais , Automação , Humanos , Camundongos , Camundongos Transgênicos , Ratos , Valores de Referência , Sensibilidade e Especificidade
15.
World J Gastrointest Oncol ; 8(5): 427-38, 2016 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-27190582

RESUMO

Colorectal cancer (CRC) is the fourth most common cancer in the United Kingdom and is the second largest cause of cancer related death in the United Kingdom after lung cancer. Currently in the United Kingdom there is not a diagnostic test that has sufficient differentiation between patients with cancer and those without cancer so the current referral system relies on symptomatic presentation in a primary care setting. Raman spectroscopy and surface enhanced Raman spectroscopy (SERS) are forms of vibrational spectroscopy that offer a non-destructive method to gain molecular information about biological samples. The techniques offer a wide range of applications from in vivo or in vitro diagnostics using endoscopic probes, to the use of micro-spectrometers for analysis of biofluids. The techniques have the potential to detect molecular changes prior to any morphological changes occurring in the tissue and therefore could offer many possibilities to aid the detection of CRC. The purpose of this review is to look at the current state of diagnostic technology in the United Kingdom. The development of Raman spectroscopy and SERS in clinical applications relation for CRC will then be discussed. Finally, future areas of research of Raman/SERS as a clinical tool for the diagnosis of CRC are also discussed.

16.
Lung Cancer ; 94: 88-95, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26973212

RESUMO

OBJECTIVES: Developing screening and diagnosis methodologies based on novel biomarkers should allow for the detection of the lung cancer (LC) and possibly at an earlier stage and thereby increase the effectiveness of clinical interventions. Here, our primary objective was to evaluate the potential of spontaneous sputum as a source of non-invasive metabolomic biomarkers for LC status. MATERIALS AND METHODS: Spontaneous sputum was collected and processed from 34 patients with suspected LC, alongside 33 healthy controls. Of the 34 patients, 23 were subsequently diagnosed with LC (LC(+), 16 NSCLC, six SCLC, and one radiological diagnosis), at various stages of disease progression. The 67 samples were analysed using flow infusion electrospray ion mass spectrometry (FIE-MS) and gas-chromatography mass spectrometry (GC-MS). RESULTS: Principal component analysis identified negative mode FIE-MS as having the main separating power between samples from healthy and LC. Discriminatory metabolites were identified using ANOVA and Random Forest. Indications of potential diagnostic accuracy involved the use of receiver operating characteristic/area under the curve (ROC/AUC) analyses. This approach identified metabolites changes that were only observed with LC. Metabolites with AUC values of greater than 0.8 which distinguished between LC(+)/LC(-) binary classifications where identified and included Ganglioside GM1 which has previously been linked to LC. CONCLUSION: This study indicates that metabolomics based on sputum can yield metabolites that can be used as a diagnostic and/or discriminator tool. These could aid clinical intervention and targeted diagnosis of LC within an 'at risk' LC(-) population group. The use of sputum as a non-invasive source of metabolite biomarkers may aid in the development of an at-risk population screening programme for lung cancer or enhanced clinical diagnostic pathways.


Assuntos
Biomarcadores Tumorais , Neoplasias Pulmonares/metabolismo , Metaboloma , Metabolômica , Escarro/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise por Conglomerados , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino , Metabolômica/métodos , Pessoa de Meia-Idade , Curva ROC , Fatores de Risco , Espectrometria de Massas por Ionização por Electrospray
17.
PLoS One ; 11(2): e0149095, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26872143

RESUMO

Chronic Obstructive Pulmonary Disease (COPD) is a major source of mortality and morbidity worldwide. The microbiome associated with this disease may be an important component of the disease, though studies to date have been based on sequencing of the 16S rRNA gene, and have revealed unequivocal results. Here, we employed metagenomic sequencing of the upper bronchial tract (UBT) microbiome to allow for greater elucidation of its taxonomic composition, and revealing functional changes associated with the disease. The bacterial metagenomes within sputum samples from eight COPD patients and ten 'healthy' smokers (Controls) were sequenced, and suggested significant changes in the abundance of bacterial species, particularly within the Streptococcus genus. The functional capacity of the COPD UBT microbiome indicated an increased capacity for bacterial growth, which could be an important feature in bacterial-associated acute exacerbations. Regression analyses correlated COPD severity (FEV1% of predicted) with differences in the abundance of Streptococcus pneumoniae and functional classifications related to a reduced capacity for bacterial sialic acid metabolism. This study suggests that the COPD UBT microbiome could be used in patient risk stratification and in identifying novel monitoring and treatment methods, but study of a longitudinal cohort will be required to unequivocally relate these features of the microbiome with COPD severity.


Assuntos
Brônquios/microbiologia , Metagenoma , Doença Pulmonar Obstrutiva Crônica/microbiologia , Idoso , Feminino , Humanos , Masculino , Microbiota , Doença Pulmonar Obstrutiva Crônica/patologia , Análise de Sequência de DNA , Índice de Gravidade de Doença
18.
Springerplus ; 4: 342, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26185744

RESUMO

PURPOSE: ARFs are a family of Ras-related GTP binding proteins, ARF6, in particular, is implicated in cancer invasion and metastasis. However, the role of ARF proteins in prostate cancer have yet to be investigated. METHODS: Immunohistochemical staining for ARF6 was performed on a prostate cancer tissue microarray with patient matched normal specimens. RESULTS: Antibody staining was significantly over-expressed in prostate cancer patient samples compared to normal patient tissue and a trend towards increased staining intensity in cancer samples with Gleason scores of 8 and above (metastatic disease). CONCLUSION: Due to high homology between members of the ARF family we could not determine if ARF 6 was the only ARF over-expressed in the prostate cancer samples. However, we are the first to show that ARF-GTPases are over expressed in prostate cancer which provides further insight into the molecular biology of prostate cancer.

19.
Tumori ; 100(6): 620-4, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25688495

RESUMO

AIM AND BACKGROUND: A reduction of gynaecological adverse events has been reported in trials comparing aromatase inhibitors with tamoxifen as adjuvant treatment in postmenopausal women with early breast cancer, but there is a paucity of randomised studies specifically investigating their effects on the uterus. We report here the results of a prospective phase III trial comparing the effects of tamoxifen and exemestane by transvaginal ultrasound (TVUS). PATIENTS AND METHODS: Postmenopausal patients with ER+ early breast cancer were randomised to receive tamoxifen 20 mg once daily or exemestane 25 mg once daily as adjuvant hormone therapy. TVUS was performed at baseline and at 6 and 12 months to measure endometrial thickness (ET) and uterine volume (UV). RESULTS: A total of 123 women were randomised to tamoxifen (n = 61) or exemestane (n = 62). A significantly higher proportion of patients in the tamoxifen group had increased ET at 6 and 12 months from randomisation compared with the exemestane group (66.1% and 64.3% versus 12.1% and 6.8%, respectively; P < 0.0001). Mean ET and UV also significantly increased with tamoxifen compared to exemestane at both time points (P < 0.01 for all comparisons). CONCLUSION: Tamoxifen is associated with endometrial thickening and increased uterine volume in a significant proportion of postmenopausal women with early breast cancer. Our study confirms the lack of endometrial effects of exemestane, which may be of interest to patients and clinicians when choosing among adjuvant endocrine options for breast cancer.


Assuntos
Androstadienos/efeitos adversos , Antineoplásicos Hormonais/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Endossonografia , Tamoxifeno/efeitos adversos , Doenças Uterinas/prevenção & controle , Útero/efeitos dos fármacos , Útero/diagnóstico por imagem , Idoso , Androstadienos/administração & dosagem , Antineoplásicos Hormonais/administração & dosagem , Inibidores da Aromatase/efeitos adversos , Neoplasias da Mama/química , Quimioterapia Adjuvante , Esquema de Medicação , Endométrio/diagnóstico por imagem , Endométrio/efeitos dos fármacos , Endométrio/patologia , Endossonografia/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Tamanho do Órgão/efeitos dos fármacos , Pós-Menopausa , Estudos Prospectivos , Tamoxifeno/administração & dosagem , Resultado do Tratamento , Doenças Uterinas/induzido quimicamente , Doenças Uterinas/diagnóstico por imagem , Útero/patologia , Vagina
20.
Transl Res ; 163(1): 19-26, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24095955

RESUMO

The 5-year survival rate for advanced head and neck cancers is 50%. There is currently no noninvasive method or effective screening procedure available to diagnose head and neck cancer at the earliest stages when it is still highly curable. This study aims to show how Fourier transform infrared (FTIR) spectroscopy could be used as a sensitive, noninvasive, low cost technique to diagnose head and neck cancer at an earlier stage and, thus, increase the likelihood of survival. Sputum samples were collected from 16 cases with oral or oropharyngeal cancer, 8 cases with laryngeal cancer patients and 15 normal controls. Cell pellets were produced from each of these samples and used to generate FTIR spectra within the 'biochemical fingerprint' wavenumber region of 1800 to 950 cm(-1). Discrimination between cancer and normal sputum was achieved using infrared wavenumbers 1650 cm(-1), 1550 cm(-1), and 1042 cm(-1) determined by robust feature selection. These 3 wavenumbers were used to develop potential models to discriminate both oropharyngeal and laryngeal cancer from normal control. In cancer cases, the absorbance levels for 1550 cm(-1) were increased relative to controls, whereas 1042 cm(-1) absorbance was decreased suggesting changes to protein and glycoprotein structure within sputa cells. This preliminary study shows potential for how FTIR could be developed into a simplistic diagnostic tool that could easily be implemented by a nonspecialist to diagnose and monitor head and neck cancer. The method could especially provide a means for detecting laryngeal cancer hidden from noninvasive observation.


Assuntos
Neoplasias Laríngeas/diagnóstico , Neoplasias Bucais/diagnóstico , Neoplasias Orofaríngeas/diagnóstico , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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