Study of white matter at the centrum semiovale level with magnetic resonance spectroscopy and diffusion tensor imaging in cerebral small vessel disease.

White matter lesion (WML) in magnetic resonance imaging is commonly observed in patients with cerebral small vessel disease (SVD), but the pathological mechanism of WML in SVD is still unclear. We observed the metabolism and microscopic anatomy of white matter in SVD patients. Twelve subjects clinically diagnosed with SVD and 6 normal control subjects were examined with magnetic resonance spectroscopy (MRS) and diffusion tensor imaging (DTI). The white matter at the centrum semiovale level was selected as the region of interest (ROI). The ROI metabolism parameters, including N-acetyl-l-aspartic acid (NAA), creatine (Cr), and choline (Cho) were measured by MRS. Microscopic parameters such as mean diffusion (MD) and fractional anisotropy (FA) in ROI were obtained by DTI. Compared with the normal control group, bilateral MD values in the SVD group were significantly elevated, whereas bilateral FA values in SVD were decreased, but the difference was not statistically significant. Additionally, NAA/Cho, Cho/Cr, and NAA/Cr showed no significant statistical differences. Our study suggests that the mechanisms of the SVD cognitive impairment are related to damage of the white matter structures rather than to brain metabolism.

CircRNA_010763 promotes growth and invasion of lung cancer through serving as a molecular sponge of miR-715 to induce c-Myc expression.

OBJECTIVE: This study aims to investigate the regulatory effect of circRNA_010763 on the growth and invasion of non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: qRT-PCR was performed to detect the expressions of circRNA_010763 and c-Myc in human NSCLC tissues and cells. CCK-8 assay was performed to evaluate the A549 cells proliferation and transwell assay was performed to evaluate the A549 cells migration. The correlation between miR-715 and circRNA_010763 was detected by statistical analysis. Bioinformatics prediction and Luciferase assay were performed to explore the interaction and binding site of circRNA_010763 and miR-715, miR-715 and c-Myc, respectively. RESULTS: We found that both circRNA_010763 and c-Myc were upregulated in human NSCLC tissues and cells. qRT-PCR and CCK-8 assay showed that circRNA_010763 expression is associated with the proliferation of NSCLC cells. Transwell assay showed that circRNA_010763 regulated the migration ability of NSCLC cells. The bioinformatics prediction and Luciferase assay demonstrated that circRNA_010763 can sponge with miR-715, serving as a molecular sponge to further regulate the expression of c-Myc. CONCLUSIONS: In this study, we found that circRNA_010763 was highly expressed in human NSCLC tissues, which could promote tumor proliferation, migration and invasion through serving as a molecular sponge by modulating the inhibitory effect of miR-715 on oncogene c-Myc.

Stimulated electron energy loss and gain in an electron microscope without a pulsed electron gun.

We report on a novel way of performing stimulated electron energy-loss and energy-gain spectroscopy (sEELS/sEEGS) experiments that does not require a pulsed gun. In this scheme, a regular scanning transmission electron microscope (STEM) equipped with a conventional continuous electron gun is fitted with a modified EELS detector and a light injector in the object chamber. The modification of the EELS detector allows one to expose the EELS camera during tunable time intervals that can be synchronized with nanosecond laser pulses hitting the sample, therefore allowing us to collect only those electrons that have interacted with the sample under light irradiation. Using  ∼ 5 ns laser pulses of  ∼ 2 eV photon energy on various plasmonic silver samples, we obtain evidence of sEELS/sEEGS through the emergence of up to two loss and gain peaks in the spectra at  ±â€¯2 and  ±â€¯4 eV. Because this approach does not involve any modification of the gun, our method retains the original performances of the microscope in terms of energy resolution and spectral imaging with and without light injection. Compared to pulsed-gun techniques, our method is mainly limited to a perturbative regime (typically no more that one gain event per incident electron), which allows us to observe resonant effects, in particular when the plasmon energy of a silver nanostructure matches the laser photon energy. In this situation, EELS and EEGS signals are enhanced in proportion to n+1 and n, respectively, where n is the average plasmon population due to the external illumination. The n term is associated with stimulated loss and gain processes, and the term of 1 corresponds to conventional (spontaneous) loss. The EELS part of the spectrum is therefore an incoherent superposition of spontaneous and stimulated EEL events. This is confirmed by a proper quantum-mechanical description of the electron/light/plasmon system incorporating light-plasmon and plasmon-electron interactions, as well as inelastic plasmon decay.

[Isolation and sequence analysis of a mitochondrial DNA fragment associated with CMS in Hong Lian type rice].

A CMS line specific mtDNA band TA1 was isolated by comparing the mtDNAs of CMS line and maintainer line using AFLP technique. The Northern blot analysis of the TA1 mtDNA fragment show that it transcripts only one RNA molecular each in CMS line, maintain line and the first filial generation, but the RNA moleculars are different among each other. By sequencing, the fragment is found to be 202 base pairs in length. It contains code ATG, ATT, AGA and AGG, two small repeated sequences 5'TGTAC3' and 5'ATTATTTT3' and one small inverted-repeated sequence 5'GGGAAACA3'. The results imply that the mtDNA fragment may be a coding region and may be relative to CMS of Hong Lian type rice.