RESUMO
The analysis of volatile organic compounds (VOCs) as a non-invasive method for disease monitoring, such as type 2 diabetes (T2D) has shown potential over the years although not yet set in clinical practice. Longitudinal studies to date are limited and the understanding of the underlying VOC emission over the age is poorly understood. This study investigated longitudinal changes in VOCs present in faecal headspace in two mouse models of T2D - Cushing's syndrome and single Afmid knockout mice. Longitudinal changes in bodyweight, blood glucose levels and plasma insulin concentration were also reported. Faecal headspace analysis was carried out using selected ion flow tube mass spectrometry (SIFT-MS) and thermal desorption coupled to gas chromatography-mass spectrometry (TD-GC-MS). Multivariate data analysis of the VOC profile showed differences mainly in acetic acid and butyric acid able to discriminate the groups Afmid and Cushing's mice. Moreover, multivariate data analysis revealed statistically significant differences in VOCs between Cushing's mice/wild-type (WT) littermates, mainly short-chain fatty acids (SCFAs), ketones, and alcohols, and longitudinal differences mainly attributed to methanol, ethanol and acetone. Afmid mice did not present statistically significant differences in their volatile faecal metabolome when compared to their respective WT littermates. The findings suggested that mice developed a diabetic phenotype and that the altered VOC profile may imply a related change in gut microbiota, particularly in Cushing's mice. Furthermore, this study provided major evidence of age-related changes on the volatile profile of diabetic mice.
Assuntos
Arilformamidase/metabolismo , Síndrome de Cushing/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Metaboloma , Compostos Orgânicos Voláteis/metabolismo , Animais , Arilformamidase/genética , Glicemia/metabolismo , Síndrome de Cushing/diagnóstico , Diabetes Mellitus Experimental/diagnóstico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/diagnóstico , Fezes , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Microbioma Gastrointestinal , Insulina/sangue , Estudos Longitudinais , Masculino , Camundongos , Camundongos Knockout , Monitorização Fisiológica , Análise Multivariada , Obesidade/metabolismoRESUMO
PURPOSE: Nail damage is common amongst patients receiving chemotherapy causing disfigurement and pain. This investigation evaluated whether a topical balm containing steam-extracted, bioactive polyphenolic-rich herbal oils blended with organic waxes could protect the nails via their reported anti-inflammatory, analgesic, anti-oxidant and anti-microbial properties. METHODS: 60 patients (23M, 37F) were randomised to apply (2-3/day) either the plant balm (PB) or a petroleum control (PC) to their nail beds. Demographics, type and number of chemotherapy cycles did not differ between the two groups, recruited between Sept 2015 and Sept 2016. An unpaired t test was used to test the differences in symptoms and physical nail damage between the two groups. RESULTS: Symptom scores recorded with the dermatology life quality questionnaire (DLQQ) were significantly better, between the start and end of chemotherapy, in the group applying the PB versus PC. Likewise, the mean fall in nail damage, scored with the Nail Psoriasis Index by the supervising physician, was also significantly different. CONCLUSION: The polyphenolic-rich essential oils and plant-based waxes in this nail bed balm profoundly reduced chemotherapy-related nail damage and improved nail-related quality of life, compared to a control. A further analysis is planned combining this balm with nail bed cooling.
Assuntos
Antineoplásicos/efeitos adversos , Onicólise/etiologia , Onicólise/terapia , Óleos de Plantas/administração & dosagem , Polifenóis/administração & dosagem , Feminino , Humanos , Masculino , Onicólise/diagnóstico , Óleos de Plantas/química , Polifenóis/química , Índice de Gravidade de Doença , Resultado do Tratamento , Reino UnidoRESUMO
ITP is an organ-specific autoimmune disorder characterised by a low platelet count whose cause is uncertain. A possible factor is food intolerance, although much of the information linking this with ITP is anecdotal. The role of food intolerance in ITP was studied by replacing a normal diet with an elemental diet (E028), but this did not increase platelet counts. Clear differences, however, were apparent between the volatile organic compounds (VOCs) in the urine headspace of patients with ITP and those present in healthy volunteers, which leads to speculation that abnormal metabolic activity of the intestinal microbiome may be a factor causing ITP. However, further work is needed to confirm this. There were also differences between the VOCs of patients on a normal diet and those on the elemental diet, and in this case, the VOCs involved are very likely to be of bacterial origin, as their production is affected by dietary manipulation. Many of these VOCs are known to be toxic.
Assuntos
Metabolômica , Púrpura Trombocitopênica Idiopática/metabolismo , Púrpura Trombocitopênica Idiopática/urina , Compostos Orgânicos Voláteis/metabolismo , Compostos Orgânicos Voláteis/urina , Adolescente , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Gravidez , Púrpura Trombocitopênica Idiopática/microbiologia , Adulto JovemRESUMO
Diagnosis of colorectal cancer is an invasive and expensive colonoscopy, which is usually carried out after a positive screening test. Unfortunately, existing screening tests lack specificity and sensitivity, hence many unnecessary colonoscopies are performed. Here we report on a potential new screening test for colorectal cancer based on the analysis of volatile organic compounds (VOCs) in the headspace of faecal samples. Faecal samples were obtained from subjects who had a positive faecal occult blood sample (FOBT). Subjects subsequently had colonoscopies performed to classify them into low risk (non-cancer) and high risk (colorectal cancer) groups. Volatile organic compounds were analysed by selected ion flow tube mass spectrometry (SIFT-MS) and then data were analysed using both univariate and multivariate statistical methods. Ions most likely from hydrogen sulphide, dimethyl sulphide and dimethyl disulphide are statistically significantly higher in samples from high risk rather than low risk subjects. Results using multivariate methods show that the test gives a correct classification of 75% with 78% specificity and 72% sensitivity on FOBT positive samples, offering a potentially effective alternative to FOBT.
Assuntos
Neoplasias Colorretais/diagnóstico , Fezes/química , Espectrometria de Massas/métodos , Compostos Orgânicos Voláteis/análise , Idoso , Biomarcadores Tumorais/análise , Colonoscopia , Feminino , Humanos , Masculino , Programas de Rastreamento/métodos , Metaboloma , Pessoa de Meia-Idade , Análise Multivariada , Sangue Oculto , Valor Preditivo dos TestesRESUMO
As nanoparticles could form aggregates in biological systems, the dynamics of their dispersity drives the temporal effect of nanoparticles in vitro. To test this hypothesis, the fumed silica nanoparticles (SiNPs) that have primary sizes of 7-14 nm and form aggregates in culture medium were selected for toxicity study in human lung A549 cells. The dispersity of SiNPs was analyzed by dynamic light scattering and transmission of electron microscopy. Cytotoxicity assays including mitochondrial activity, intracellular level of reactive oxygen species (ROS), and membrane damage together with the ¹H-NMR-based extracellular metabonomic assay were conducted to determine the temporal dose-effect relationship of SiNPs. In cell culture medium, SiNPs dispersed well initially at 25-100 µg/ml; however, they sedimented rapidly in a concentration-dependent manner. SiNPs caused a dose-dependent increase of intracellular ROS and cell membrane damage at 4 h and a loss of cell viability after 48 h. SiNPs also induced an elevation of extracellular glucose, lactate, phenylalanine, histidine, and tyrosine levels in a time- and concentration-dependent manner. The dose-effect patterns at 4 h were different from that at 12 and 24 h as assessed by both cytotoxicity and metabonomic assays. Both fitted better with polynomial regression than linear regression, implying multimode action of SiNPs at different concentrations. The early NP-cell interaction and the late sedimentation could be attributable to the temporal effects of SiNPs. The extracellular ¹H-NMR-based metabonomics demonstrated a potential as a robust nondestructive tool for monitoring the temporal effect of NPs that tend to aggregate in nature.
Assuntos
Poluentes Atmosféricos/toxicidade , Líquido Extracelular/metabolismo , Pulmão/efeitos dos fármacos , Metaboloma/efeitos dos fármacos , Nanopartículas/química , Dióxido de Silício/toxicidade , Poluentes Atmosféricos/química , Técnicas de Cultura de Células , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultura , Relação Dose-Resposta a Droga , Humanos , Pulmão/metabolismo , Pulmão/patologia , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Transmissão , Análise Multivariada , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Espalhamento de Radiação , Dióxido de Silício/química , Propriedades de SuperfícieRESUMO
BACKGROUND: The aim of this study was to determine whether volatile organic compounds (VOCs) present in the headspace of feces could be used to diagnose or distinguish between chronic diseases of the gastrointestinal tract and apparently healthy volunteers. METHODS: A total of 87 people were recruited, divided between 4 categories: healthy volunteers (n = 19), Crohn's disease (n = 22), ulcerative colitis (n = 20), and irritable bowel syndrome (n = 26). They each supplied fecal samples before, and except for the healthy volunteers, after treatment. Fecal samples were incubated in a sample bag with added purified air at 40°C and headspace samples were taken and concentrated on thermal sorption tubes. Gas chromatography-mass spectrometry then desorbed and analyzed these. The concentrations of a selection of high-abundance compounds were determined and assessed for differences in concentration between the groups. RESULTS: Crohn's disease samples showed significant elevations in the concentrations of ester and alcohol derivates of short-chain fatty acids and indole compared with the other groups; indole and phenol were elevated in ulcerative colitis and irritable bowel syndrome but not at a statistically significant level. After treatment, the levels of many of the VOCs were significantly reduced and were more similar to those concentrations in healthy controls. CONCLUSIONS: The abundance of a number of VOCs in feces differs markedly between Crohn's disease and other gastrointestinal conditions. Following treatment, the VOC profile is altered to more closely resemble that of healthy volunteers.
Assuntos
Infecções Bacterianas/diagnóstico , Colite Ulcerativa/diagnóstico , Doença de Crohn/diagnóstico , Fezes/química , Síndrome do Intestino Irritável/diagnóstico , Compostos Orgânicos Voláteis/análise , Bactérias/isolamento & purificação , Infecções Bacterianas/microbiologia , Estudos de Casos e Controles , Doença Crônica , Colite Ulcerativa/microbiologia , Doença de Crohn/microbiologia , Fezes/microbiologia , Feminino , Seguimentos , Cromatografia Gasosa-Espectrometria de Massas , Voluntários Saudáveis , Humanos , Síndrome do Intestino Irritável/microbiologia , Masculino , PrognósticoRESUMO
BACKGROUND: MicroRNA (miRNA) directed gene repression is an important mechanism of posttranscriptional regulation. Comprehensive analyses of how microRNA influence biological processes requires paired miRNA-mRNA expression datasets. However, a review of both GEO and ArrayExpress repositories revealed few such datasets, which was in stark contrast to the large number of messenger RNA (mRNA) only datasets. It is of interest that numerous primary miRNAs (precursors of microRNA) are known to be co-expressed with coding genes (host genes). RESULTS: We developed a miRNA-mRNA interaction analyses pipeline. The proposed solution is based on two miRNA expression prediction methods - a scaling function and a linear model. Additionally, miRNA-mRNA anti-correlation analyses are used to determine the most probable miRNA gene targets (i.e. the differentially expressed genes under the influence of up- or down-regulated microRNA). Both the consistency and accuracy of the prediction method is ensured by the application of stringent statistical methods. Finally, the predicted targets are subjected to functional enrichment analyses including GO, KEGG and DO, to better understand the predicted interactions. CONCLUSIONS: The MMpred pipeline requires only mRNA expression data as input and is independent of third party miRNA target prediction methods. The method passed extensive numerical validation based on the binding energy between the mature miRNA and 3' UTR region of the target gene. We report that MMpred is capable of generating results similar to that obtained using paired datasets. For the reported test cases we generated consistent output and predicted biological relationships that will help formulate further testable hypotheses.
Assuntos
Biologia Computacional/métodos , MicroRNAs/genética , MicroRNAs/metabolismo , Transcriptoma , Mapeamento Cromossômico , Humanos , Modelos Lineares , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos TestesRESUMO
The relative abundance of different groups of sulphate-reducing bacteria (SRB) in faecal DNA collected before and after therapy from patients suffering from Crohn's disease (CD), irritable bowel syndrome (IBS) or ulcerative colitis (UC) has been compared with that from healthy controls. Growth tests revealed that SRB were not more abundant in samples from patients with CD before treatment than in the healthy control group. For most of the 128 samples available, these preliminary results were confirmed using degenerate PCR primers that amplify the dsrAB gene. However, some samples from patients with CD before treatment contained a growth inhibitor that was absent from IBS or UC samples. In-depth sequencing of PCR-generated dsrB fragments revealed that the diversity detected was surprisingly low, with only eight strains of SRB and the sulphite-reducing bacterium, Bilophila wadsworthia, detected above the 0.1% threshold. The proportion of the two major species detected, B. wadsworthia and Desulfovibrio piger, was as high as 93.5% of the total SRB population in the healthy control group and lower in all patient groups. Four previously undescribed species were found: it is impossible to predict whether they are sulphate or sulphite-reducing bacteria.
Assuntos
Bactérias/classificação , Bactérias/isolamento & purificação , Biota , Fezes/microbiologia , Doenças Inflamatórias Intestinais/microbiologia , Metagenoma , Sulfatos/metabolismo , Antibacterianos/uso terapêutico , Bactérias/genética , Bactérias/metabolismo , Primers do DNA/genética , DNA Bacteriano/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Experimentação Humana , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Oxirredução , Reação em Cadeia da Polimerase/métodosRESUMO
In this paper, we present an optical diagnostic assay consisting of a mixture of environmental-sensitive fluorescent dyes combined with multivariate data analysis for quantitative and qualitative examination of biological and clinical samples. The performance of the assay is based on the analysis of spectrum of the selected fluorescent dyes with the operational principle similar to electronic nose and electronic tongue systems. This approach has been successfully applied for monitoring of growing cell cultures and identification of gastrointestinal diseases in humans.
Assuntos
Bioensaio/métodos , Biomimética/métodos , Biopolímeros/análise , Diagnóstico por Computador/métodos , Corantes Fluorescentes , Gastroenteropatias/diagnóstico , Espectrometria de Fluorescência/métodos , Algoritmos , Gastroenteropatias/metabolismo , Humanos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Previous studies have indicated that volatile compounds specific to bladder cancer may exist in urine headspace, raising the possibility that headspace analysis could be used for diagnosis of this particular cancer. In this paper, we evaluate the use of a commercially available gas sensor array coupled with a specifically designed pattern recognition algorithm for this purpose. The best diagnostic performance that we were able to obtain with independent test data provided by healthy volunteers and bladder cancer patients was 70% overall accuracy (70% sensitivity and 70% specificity). When the data of patients suffering from other non-cancerous urological diseases were added to those of the healthy controls, the classification accuracy fell to 65% with 60% sensitivity and 67% specificity. While this is not sufficient for a diagnostic test, it is significantly better than random chance, leading us to conclude that there is useful information in the urine headspace but that a more informative analytical technique, such as mass spectrometry, is required if this is to be exploited fully.
Assuntos
Biomarcadores Tumorais/urina , Carcinoma de Células de Transição/urina , Gases/urina , Urinálise/instrumentação , Neoplasias da Bexiga Urinária/urina , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células de Transição/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Neoplasias da Bexiga Urinária/diagnósticoRESUMO
We investigated the potential of two different electronic noses (EN; code named "Rob" and "Walter") to differentiate between sputum headspace samples from tuberculosis (TB) patients and non-TB patients. Only samples from Ziehl-Neelsen stain (ZN)- and Mycobacterium tuberculosis culture-positive (TBPOS) sputum samples and ZN- and culture-negative (TBNEG) samples were used for headspace analysis; with EN Rob, we used 284 samples from TB suspects (56 TBPOS and 228 TBNEG samples), and with EN Walter, we used 323 samples from TB suspects (80 TBPOS and 243 TBNEG samples). The best results were obtained using advanced data extraction and linear discriminant function analysis, resulting in a sensitivity of 68%, a specificity of 69%, and an accuracy of 69% for EN Rob; for EN Walter, the results were 75%, 67%, and 69%, respectively. Further research is still required to improve the sensitivity and specificity by choosing more selective sensors and type of sampling technique.
Assuntos
Técnicas de Química Analítica/métodos , Técnicas de Laboratório Clínico/métodos , Escarro/química , Tuberculose Pulmonar/diagnóstico , Humanos , Sensibilidade e EspecificidadeRESUMO
Identification and quantification of the opiates morphine and thebaine has been achieved in three commercial poppy cultivars using FTIR-ATR spectroscopy, from a simple and rapid methanolic extraction, suitable for field analysis. The limits of detection were 0.13 mg/ml (0.013%, w/v) and 0.3 mg/ml (0.03%, w/v) respectively. The concentrations of opiates present were verified with HPLC-MS. The chemometrics has been used to identify specific "signature" peaks in the poppy IR spectra for characterisation of cultivar by its unique fingerprint offering a potential forensic application in opiate crop analysis.
Assuntos
Algoritmos , Analgésicos Opioides/análise , Técnicas Biossensoriais/métodos , Técnicas de Química Combinatória/métodos , Papaver/química , Extratos Vegetais/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Sensibilidade e EspecificidadeRESUMO
Cleaning verification is the process by which pharmaceutical manufacturing equipment is determined as sufficiently clean to allow manufacture to continue. Surface-enhanced Raman spectroscopy (SERS) is a very sensitive spectroscopic technique capable of detection at levels appropriate for cleaning verification. In this paper, commercially available Klarite SERS substrates were employed in order to obtain the necessary enhancement of signal for the identification of chemical species at concentrations of 1 to 10 ng/cm2, which are relevant to cleaning verification. The SERS approach was combined with principal component analysis in the identification of drug compounds recovered from a contaminated steel surface.
Assuntos
Indústria Farmacêutica/métodos , Monitoramento Ambiental/métodos , Análise Espectral Raman/métodos , Contaminação de Medicamentos/prevenção & controle , Indústria Farmacêutica/instrumentação , Contaminação de Equipamentos/prevenção & controle , Análise de Componente PrincipalRESUMO
A system for fiber-optic probing in dissolution testing of solid pharmaceutical formulations has been constructed. The system is based on an imaging spectrometer and a charged coupled device (CCD) detector and includes 12 fiber-optic probes with a novel dual-path design. UV light was produced by a small arc deuterium lamp illuminating an optical fiber bundle. Twelve fiber-optic dipping probes were constructed with a reflection geometry. A 5 mm diameter lens was used to achieve a parallel light beam. The light passed back and forth through the flow-through cuvette defined by a sapphire window and a coated aluminium mirror. The mirror was cut in half and each segment was tilted and set at different distances from the window to obtain two separate paths with different lengths. Two receiver fibers were used for each probe to collect the transmitted light. The 24 receiver fibers from the 12 probes were bunched to a linear bundle and fed to an imaging spectrometer and the corresponding spectra were detected with a 512 x 512 pixel cooled CCD detector. The sampling interval was typically a few seconds for all probes. A software package was developed for data recording and on-line analysis. The program includes tools for multi-component analysis. The system was tested for different tablet formulations. Prednisone 50 mg tablets, normally used for control tests of dissolution baths, were followed for 3 h. Secondly, an extended release low dosage tablet was followed for 7 h resulting in a linear dissolution profile. Finally, a combination tablet containing two active drugs was tested for 60 min profiles. In the latter case, separate dissolution curves for the two active components were obtained. Future work will mainly focus on further development of the multi-component capability of the system.