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1.
BMC Cancer ; 17(1): 767, 2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-29141603

RESUMEN

BACKGROUND: Haematuria is a common finding in general practice which requires visual inspection of the bladder by cystoscopy as well as upper tract imaging. In addition, patients with non-muscle invasive bladder cancer (NMIBC) often require surveillance cystoscopy as often as three monthly depending on disease risk. However, cystoscopy is an invasive procedure which is uncomfortable, requires hospital attendance and is associated with a risk of urinary tract infection. We have developed the UroMark assay, which can detect 150 methylation specific alteration specific to bladder cancer using DNA from urinary sediment cells. METHODS: DETECT I and DETECT II are two multi-centre prospective observational studies designed to conduct a robust validation of the UroMark assay. DETECT I will recruit patients having diagnostic investigations for haematuria to determine the negative predictive value of the UroMark to rule out the presence of bladder cancer. DETECT II will recruit patients with new or recurrent bladder cancer to determine the sensitivity of the UroMark in detecting low, intermediate and high grade bladder cancer. NMIBC patients in DETECT II will be followed up with three monthly urine sample collection for 24 months while having surveillance cystoscopy. DETECT II will include a qualitative analysis of semi-structured interviews to explore patients' experience of being diagnosed with bladder cancer and having cystoscopy and a urinary test for bladder cancer surveillance. Results of the UroMark will be compared to cystoscopy findings and histopathological results in patients with bladder cancer. DISCUSSION: A sensitive and specific urinary biomarker will revolutionise the haematuria diagnostic pathway and surveillance strategies for NMIBC patients. None of the six approved US Food and Drug Administration urinary test are recommended as a standalone test. The UroMark assay is based on next generation sequencing technology which interrogates 150 loci and represents a step change compared to other biomarker panels. This enhances the sensitivity of the test and by using a random forest classifier approach, where the UroMark results are derived from a cut off generated from known outcomes of previous samples, addresses many shortcomings of previous assays. TRIAL REGISTRATION: Both trails are registered on clinicaltrials.gov. DETECT I: NCT02676180 (18th December 2015). DETECT II: NCT02781428 (11th May 2016).


Asunto(s)
Biomarcadores de Tumor , Protocolos Clínicos , Biopsia Líquida/métodos , Neoplasias de la Vejiga Urinaria/diagnóstico , Femenino , Humanos , Masculino , Estudios Prospectivos
2.
Ying Yong Sheng Tai Xue Bao ; 32(7): 2426-2432, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34313060

RESUMEN

Based on a field water table drawdown manipulation platform of Naleqiao marsh on the Rueorgai Plateau, we lifted in situ soil block of 1 m×1 m by 20 cm for simulating water table decline, and analyzed the response of carbon, nitrogen, and phosphorus stoichiometry in the wetland species Carex muliensis from June to September 2020. The results showed that there was no significant difference in leaf C content during the whole growing season, while N and P content gra-dually decreased along the growing season. After the drawdown of water table, the C content in leaves during the growing season was not consistent. Water table drawdown increased leaf C content in the early and middle growth stages, but changed little in the peak growth stage. Water table drawdown significantly increased leaf N content, while significantly decreased leaf P content. C:N, C:P, and N:P for leaves all increased along the whole growing period. The relative growth rate of C. muliensis was positively correlated with leaf C:N, but negatively correlated with leaf C:P and N:P. Water table drawdown significantly decreased leaf C:N, while significantly increased leaf C:P and N:P, which significantly reduced the relative growth rate of C. muliensis. The decrease of foliar P content induced by water table drawdown was the main regulating factor for the decrease of single leaf weight and specific leaf weight.


Asunto(s)
Carex (Planta) , Agua Subterránea , Carbono/análisis , China , Nitrógeno/análisis , Fósforo/análisis , Hojas de la Planta/química , Suelo , Humedales
3.
PeerJ ; 8: e9904, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33062420

RESUMEN

Zoigê Plateau, China's largest plateau marsh wetland, has experienced large-scale degradation of the marsh wetland and evolution of the wetland landscape pattern over the past 40 years due to climate warming and human activities. How exactly do the wetland landscape pattern characteristics change? How do climatic change and human activities affect the wetland evolution? These questions are yet to be systematically investigated. In order to investigate changes to the marsh wetland on the Zoigê Plateau, field investigations, spatial and statistical analysis were undertaken. Findings from our study indicate that from 1977-2016, the area of marsh wetland on the Plateau reduced by 56.54%, approximately 66,700 hm2 of marsh wetland has been lost. The centroids of both marsh and marshy meadow migrated and the landscape centroid migration behaviors were also correlated with the distribution and variation of the marsh wetland on different slopes. In addition, the number of marsh landscape patches initially increased before decreasing; the number of marshy meadow landscape patches also recorded an initial increase, followed by a decline before a final increase. As the effects of human activities weakened, the aggregation degrees of both marsh and marshy meadow increased. Overall, the fragmentation degree, diversity and fractal dimension of the marsh wetland all declined. An investigation into the driving factors affecting the Plateau area shows that the increase of annual average temperature was the natural factor while trenching and overgrazing were the main human factors resulting in wetland degradation. Results from this study provide basic data and theoretical foundation for the protection and restoration of marsh wetland in alpine regions.

4.
Zhen Ci Yan Jiu ; 45(12): 1006-9, 2020 Dec 25.
Artículo en Zh | MEDLINE | ID: mdl-33415861

RESUMEN

OBJECTIVE: To investigate the anesthetic effect of combined acupuncture-medicine anesthesia in microwave ablation of benign thyroid nodules and its effect on serum ß-endorphin. METHODS: A total of 60 patients who met the inclusion criteria and received microwave ablation of benign thyroid nodules were randomly divided into the treatment group and the control group, with 30 patients in each. The patients in the treatment group were given combined acupuncture-medicine anesthesia, and those in the control group were given intravenous anesthesia. The two groups were compared in terms of the sedative and analgesic effects of anesthesia, amount of anesthetics used, incidence rate of intraoperative snore and respiratory depression, and change in serum ß-endorphin level before anesthesia, before surgery, and after the surgery. RESULTS: Both groups obtained satisfactory anesthetic effects. Compared with the control group, the sedation score, the amounts of fentanyl and propofol used, the incidence rates of intraoperative snore and respiratory depression in the treatment group were obviously lower (P<0.05, P<0.01). The treatment group had an increase in serum ß-endorphin level before surgery and at the end of surgery (P<0.05), while the control group showed no significant change in serum ß-endorphin level at each time point. CONCLUSION: In microwave ablation of benign thyroid nodules, combined acupuncture-medicine anesthesia has good sedative and analgesic effects and can reduce the amounts of anesthetics used as well as the incidence rates of intraoperative snore and respiratory depression. The analgesic effect of acupuncture anesthesia is associated with increased ß-endorphin secretion.


Asunto(s)
Analgesia por Acupuntura , Anestesia , Medicina , Nódulo Tiroideo , Anestésicos Intravenosos , Humanos , betaendorfina
5.
Abdom Imaging ; 33(4): 489-92, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-17619097

RESUMEN

OBJECTIVE: We describe CT features of our three cases with localized Castleman disease in the retroperitoneum and review literature. Besides those CT features, which have been reported before, we mainly present some newly discovered CT findings of the disease. These new CT findings include the sign of peripheral 'rim-like' enhancement at the early phase of an enhanced CT scan, a higher ratio of the left sided retroperitoneal location to the right side and the presence of local peritoneal thickening around the lesion. In addition, the feeding artery of the lesion is more visually pronounced than ever before by a 16-detector CT scanner. CONCLUSION: After reviewing the literature and comparing with their histological findings, we suggest these newly discovered findings are relatively characteristic CT features of the disease. Moreover, multi-detector helical CT can now show more details of the disease than ever before.


Asunto(s)
Enfermedad de Castleman/diagnóstico por imagen , Espacio Retroperitoneal/diagnóstico por imagen , Tomografía Computarizada Espiral , Adulto , Enfermedad de Castleman/patología , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Espacio Retroperitoneal/patología
6.
Cancer Treat Rev ; 66: 56-63, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29684744

RESUMEN

BACKGROUND: Blood-based biomarkers are a neglected resource in bladder cancer, where the mainstay of focus has been on urinary biomarkers. However, blood-based biomarkers are gaining popularity in other solid cancers, particularly circulating tumour cells (CTCs) and circulating nucleic acids. In this systematic review, we identify and discuss the diagnostic value of CTC, cell-free DNA and RNA based biomarkers in bladder cancer. METHODS: A MEDLINE/Pubmed systematic search was performed using the following keywords: (bladder cancer) AND (blood OR plasma OR serum) AND biomarker AND (DNA OR RNA OR cfDNA OR cell-free DNA OR RNA OR CTC). All studies including blood-based biomarkers based on DNA, RNA and CTCs were reviewed. Of the included studies, studies reporting sensitivity, specificity and/or AUC/ROC values were further described. RESULTS: Systematic searched yielded 47 studies that were eligible, of which 21, 19 and 3 studies reported DNA, RNA and CTC biomarkers respectively. 15 of these studies included sensitivity, specificity and/or AUC/ROC values. Biomarkers sensitivity and specificity ranged widely at 2.4-97.6% and 43.3-100% respectively. Median number of patients recruited in the studies was 56 (IQR 41-90). Only 3 studies included an independent validation cohort. The highest sensitivity and specificity pairing achieved in the validation cohort was 80.0% and 89.1% respectively. CONCLUSIONS: This systematic review provides a comprehensive overview of the blood-based CTC and nucleic acid biomarkers that have been investigated. An overlap in interest of targets between studies suggests that these could be promising biomarkers, but few biomarkers achieve high sensitivity and specificity, and fewer still have been validated independently.


Asunto(s)
Células Neoplásicas Circulantes/metabolismo , Ácidos Nucleicos/sangre , Neoplasias de la Vejiga Urinaria/diagnóstico , Femenino , Humanos , Masculino , Células Neoplásicas Circulantes/patología , Neoplasias de la Vejiga Urinaria/patología
7.
Cancer Treat Rev ; 69: 39-52, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29902678

RESUMEN

BACKGROUND: Urinary biomarkers for the diagnosis of bladder cancer represents an area of considerable research which has been tested in both patients presenting with haematuria and non-muscle invasive bladder cancer patients requiring surveillance cystoscopy. In this systematic review, we identify and appraise the diagnostic sensitive and specificity of reported novel biomarkers of different 'omic' class and highlight promising biomarkers investigated to date. METHODS: A MEDLINE/Pubmed systematic search was performed between January 2013 and July 2017 using the following keywords: (bladder cancer OR transitional cell carcinoma OR urothelial cell carcinoma) AND (detection OR diagnosis) AND urine AND (biomarker OR assay). All studies had a minimum of 20 patients in both bladder cancer and control arms and reported sensitivity and/or specificity and/or receiver operating characteristics (ROC) curve. QUADAS-2 tool was used to assess risk of bias and applicability of studies. The search protocol was registered in the PROSPERO database (CRD42016049918). RESULTS: Systematic search yielded 115 reports were included for analysis. In single target biomarkers had a sensitivity of 2-94%, specificity of 46-100%, positive predictive value (PPV) of 47-100% and negative predictive value (NPV) of 21-94%. Multi-target biomarkers achieved a sensitivity of 24-100%, specificity of 48-100%, PPV of 42-95% and NPV of 32-100%. 50 studies achieved a sensitivity and specificity of ≥80%. Protein (n = 59) and transcriptomic (n = 21) biomarkers represents the most studied biomarkers. Multi-target biomarker panels had a better diagnostic accuracy compared to single biomarker targets. Urinary cytology with urinary biomarkers improved the diagnostic ability of the biomarker. The sensitivity and specificity of biomarkers were higher for primary diagnosis compared to patients in the surveillance setting. Most studies were case control studies and did not have a predefined threshold to determine a positive test result indicating a possible risk of bias. CONCLUSION: This comprehensive systematic review provides an update on urinary biomarkers of different 'omic' class and highlights promising biomarkers. Few biomarkers achieve a high sensitivity and negative predictive value. Such biomarkers will require external validation in a prospective observational setting before adoption in clinical practice.


Asunto(s)
Biomarcadores de Tumor/orina , Neoplasias de la Vejiga Urinaria/diagnóstico , Neoplasias de la Vejiga Urinaria/orina , Humanos , Pronóstico
8.
Clin Epigenetics ; 9: 8, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28163793

RESUMEN

BACKGROUND: Bladder cancer (BC) is one of the most common cancers in the western world and ranks as the most expensive to manage, due to the need for cystoscopic examination. BC shows frequent changes in DNA methylation, and several studies have shown the potential utility of urinary biomarkers by detecting epigenetic alterations in voided urine. The aim of this study is to develop a targeted bisulfite next-generation sequencing assay to diagnose BC from urine with high sensitivity and specificity. RESULTS: We defined a 150 CpG loci biomarker panel from a cohort of 86 muscle-invasive bladder cancers and 30 normal urothelium. Based on this panel, we developed the UroMark assay, a next-generation bisulphite sequencing assay and analysis pipeline for the detection of bladder cancer from urinary sediment DNA. The 150 loci UroMark assay was validated in an independent cohort (n = 274, non-cancer (n = 167) and bladder cancer (n = 107)) voided urine samples with an AUC of 97%. The UroMark classifier sensitivity of 98%, specificity of 97% and NPV of 97% for the detection of primary BC was compared to non-BC urine. CONCLUSIONS: Epigenetic urinary biomarkers for detection of BC have the potential to revolutionise the management of this disease. In this proof of concept study, we show the development and utility of a novel high-throughput, next-generation sequencing-based biomarker for the detection of BC-specific epigenetic alterations in urine.


Asunto(s)
Biomarcadores de Tumor/genética , Biomarcadores de Tumor/orina , Metilación de ADN , ADN de Neoplasias/orina , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/orina , Adulto , Anciano , Anciano de 80 o más Años , Islas de CpG , Detección Precoz del Cáncer , Epigénesis Genética , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Masculino , Persona de Mediana Edad , Análisis de Secuencia de ADN/métodos , Adulto Joven
9.
N Biotechnol ; 33(3): 311-30, 2016 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-26514324

RESUMEN

The REvolutionary Approaches and Devices for Nucleic Acid analysis (READNA) project received funding from the European Commission for 41/2 years. The objectives of the project revolved around technological developments in nucleic acid analysis. The project partners have discovered, created and developed a huge body of insights into nucleic acid analysis, ranging from improvements and implementation of current technologies to the most promising sequencing technologies that constitute a 3(rd) and 4(th) generation of sequencing methods with nanopores and in situ sequencing, respectively.


Asunto(s)
Biotecnología/métodos , ADN/análisis , ADN/genética , Animales , Química Clic , Exoma/genética , Humanos , Espectrometría de Masas , Análisis de Secuencia de ADN
10.
Anal Sci ; 25(2): 285-91, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19212067

RESUMEN

Realisation of a device intended for the manipulation and detection of bead-tagged DNA and other bio-molecules is presented. Acoustic radiation forces are used to manipulate polystyrene micro-beads into an optical evanescent field generated by a laser pumped ion-exchanged waveguide. The evanescent field only excites fluorophores brought within approximately 100 nm of the waveguide, allowing the system to differentiate between targets bound to the beads and those unbound and still held in suspension. The radiation forces are generated in a standing-wave chamber that supports multiple acoustic modes, permitting particles to be both attracted to the waveguide surface and also repelled. To provide further control over particle position, a novel method of switching rapidly between different acoustic modes is demonstrated, through which particles are manipulated into an arbitrary position within the chamber. A novel type of assay is presented: a mixture of streptavidin coated and control beads are driven towards a biotin functionalised surface, then a repulsive force is applied, making it possible to determine which beads became bound to the surface. It is shown that the quarter-wave mode can enhance bead to surface interaction, overcoming potential barriers caused by surface charges. It is demonstrated that by measuring the time of flight of a microsphere across the device the bead size can be determined, providing a means of multiplexing the detection, potentially detecting a range of different target molecules, or varying bead mass.


Asunto(s)
Acústica/instrumentación , Microesferas , Fenómenos Ópticos , ADN/análisis , ADN/química , Fluorescencia , Factores de Tiempo
11.
Chemistry ; 13(3): 822-8, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17154323

RESUMEN

The synthesis of supramolecular conducting nanowires can be achieved by using DNA and pyrrole. Oxidation of pyrrole in DNA-containing solutions yields a material that contains both the cationic polypyrrole (PPy) and the anionic DNA polymers. Intimate interaction of the two polymer chains in the self-assembled nanowires is indicated by FTIR spectroscopy. AFM imaging shows individual nanowires to be continuous, approximately 5 nm high and conformationally flexible. This feature allows them to be aligned by molecular combing in a similar manner to bare DNA and provides a convenient method for fabricating a simple electrical device by stretching DNA/PPy strands across an electrode gap. Current-voltage measurements confirm that the nanowires are conducting, with values typical for a polypyrrole-based material. In contrast to polymerisation of pyrrole on a DNA template in bulk solution, attempts to form similar wires by polymerisation at surface-immobilised DNA do not give a continuous coverage; instead, a beads-on-a-string appearance is observed suggesting that immobilisation inhibits the assembly process.


Asunto(s)
Sustancias Macromoleculares/síntesis química , Nanoestructuras/química , Polímeros/síntesis química , Pirroles/síntesis química , ADN/química , Conductividad Eléctrica , Sustancias Macromoleculares/química , Modelos Moleculares , Estructura Molecular , Oxidación-Reducción , Tamaño de la Partícula , Polímeros/química , Pirroles/química , Soluciones/química , Propiedades de Superficie
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