RESUMO
L625 4-wavelength dual Raman-Mie lidar was used to detect elastically Mie backscattered light at emitting wavelengths (532 and 355 nm) emitted by one Nd:YAG laser, and the nitrogen Raman light (607 and 386 nm) inelastically backscattered by nitrogen molecules at Hefei (117.3°E, 31.9°N), China from 2007 to 2013. From the four return signal profiles, highly accurate aerosol extinction and backscatter coefficients, lidar ratio, Ångström exponent, and aerosol Junge exponent can be determined. Furthermore, with a priori assumption of the real part of complex refractive index nr=1.50, the profiles of more aerosol microphysical parameters can be retrieved with their respective errors in the free troposphere, such as the imaginary part of the refractive index, Junge number density coefficient, and particle mass index. The profiles of aerosol microphysical parameters were obtained for 179 nights. Their variation and statistical features were discussed.
RESUMO
MicroRNAs (miRNAs) diagnostics can be useful for diagnosing or confirming miRNA abundance and are used in screening tests and to assess changes in miRNAs in vivo. At present, the use of traditional nucleic acid amplification assays to detect miRNAs has been limited in laboratory environment because of the time, equipment, and technical expertise required to perform these assays. A specialized, rapid affordable miRNA detection system is necessary when there are limited resources or point-of-care testing needs. We designed a portable and affordable fluorescence-based miRNA detection system based on isothermal signal amplification technology, using SYBR Green II as a fluorescent dye. To reduce costs, we chose LED as a light source and designed the corresponding optical path for LED. The portable detection system shows results consistent with those by real-time PCR, and can be used to detect miR-183 with a limit of detection of approximately 2 fmol. We used the system to detect miR-183 in tissues and blood from patients with hepatocellular carcinoma (HCC). The results from the portable detection device were compared with those from clinical trials and indicated that the miR-183 fluorescence signal could successfully identify HCC and provide information related to cancer progression.
Assuntos
Carcinoma Hepatocelular , Fluorescência , Neoplasias Hepáticas , MicroRNAs , Compostos Orgânicos/química , RNA Neoplásico , Reação em Cadeia da Polimerase em Tempo Real/métodos , Adulto , Idoso , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Pessoa de Meia-Idade , RNA Neoplásico/genética , RNA Neoplásico/metabolismoRESUMO
Oligonucleotides were screened for strongly silver-stained repetitive sequences. An 'AG'-clustered purine sequence showed strong staining, and the staining density can be compromised by disrupting the continuity of the 'AG'-clustered sequence. The staining-favored sequence was then employed in rolling circle amplification (RCA) for its product detection. A tube-staining method was developed for convenient and visual RCA assay. Moreover, by introducing GalR into RCA, d-galactose was detected by RCA tube-staining with naked eyes without any equipment. About 10 mM d-galactose can be easily identified, and the detection of d-galactose was specific in comparison with that of several other monosaccharides.
Assuntos
Galactose/análise , Técnicas de Amplificação de Ácido Nucleico/métodos , Oligonucleotídeos/análise , Coloração pela Prata/métodos , Sequência de Bases , DNA de Cadeia Simples/análise , DNA de Cadeia Simples/química , DNA de Cadeia Simples/genética , Eletroforese em Gel de Poliacrilamida , Galactose/química , Galactose/metabolismo , Oligonucleotídeos/química , Oligonucleotídeos/genética , Reprodutibilidade dos TestesRESUMO
The spatial-temporal distribution of dust aerosol is important in climate model and ecological environment. An observation experiment of the aerosol vertical distribution in the low troposphere was made using the micro-pulse lidar system from Sept. 2008 to Aug. 2009 at the oasis city Kashgar, China, which is near the major dust source area of the Taklimakan desert. The monthly averaged temporal variation of aerosol extinction profiles are given in the paper. The profile of aerosol extinction coefficient suggested that the dust aerosol could be vertically transported from the ground level to the higher altitude of above 5 km around the source region, and the temporal distribution showed that the dust aerosol layer of a few hundred meters thick appeared in the seasons of early spring and summer near the ground surface.
