Inhibitory effects of low decibel infrasound on the cardiac fibroblasts and the involved mechanism.

INTRODUCTION: Infrasound is a mechanical vibration wave with frequency between 0.0001 and 20 Hz. It has been established that infrasound of 120 dB or stronger is dangerous to humans. However, the biological effects of low decibel infrasound are largely unknown. The purpose of this study was to investigate the effects of low decibel infrasound on the cardiac fibroblasts. MATERIALS AND METHODS: The cardiac fibroblasts were isolated and cultured from Sprague-Dawley rats. The cultured cells were assigned into the following four groups: control group, angiotensin II (Ang II) group, infrasound group, and Ang II+infrasound group. The cell proliferation and collagen synthesis rates were evaluated by means of [3H]-thymidine and [3H]-proline incorporation, respectively. The levels of TGF-ß were determined by enzyme-linked immunosorbent assay. Moreover, RNAi approaches were used for the analysis of the biological functions of miR-29a, and the phosphorylation status of Smad3 was detected using western blotting analysis. RESULTS: The results showed that low decibel infrasound significantly alleviated Ang II-induced enhancement of cell proliferation and collagen synthesis. DISCUSSION: Compared with the control, Ang II markedly decreased the expression of miR-29a levels and increased the secretion of TGF-ß and phosphorylation of Smad3, which was partly reversed by the treatment with low decibel infrasound. Importantly, knockdown of miR-29a diminished the effects of infrasound on the cardiac fibroblasts. In conclusion, low decibel infrasound inhibits Ang II-stimulated cardiac fibroblasts via miR-29a targeting TGF-ß/Smad3 signaling.

Study on strength characteristics and thickening characteristics of classified-fine cemented backfill in gold mine.

For some new mines, the utilization rate of tailings is not satisfactory when using unclassified tailings as backfill aggregate for cemented backfill. At the same time, with the progress of mineral processing technology, the tailings discharged by the concentrator gradually become finer. Therefore, cemented filling with fine-grained tailings as aggregate will become the development direction of filling technology in the future. In this paper, the feasibility of fine particle tailings backfill is studied by taking the particle tailings of-200 mesh as aggregate in Shaling gold mine. The calculation shows that the utilization rate of tailings is increased from 45.1% to 90.3% by using-200 mesh tailings as filling aggregate. The response surface central composite design method (RSM-CCD) was used to study the strength of backfill with alkali-activated cementitious material as binder by taking the mass concentration of backfill slurry and sand-binder ratio as input factors. The results show that the 28-day strength of the backfill with graded fine-grained tailings as filling aggregate can reach 5.41 MPa when the sand-binder ratio is 4, which can fully meet the needs of the mine for the strength of the backfill. The thickening test of-200 mesh fine particle tailings was carried out by static limit concentration test and dynamic thickening test. In the case of adding 35 g/t BASF 6920 non-ionic flocculant, the concentration of 64.74% tail mortar can reach 67.71% after 2 h of static thickening, and the concentration can reach 69.62% after 2 h of static thickening. The feeding speed of thickener should be controlled between 0.4 and 0.59 t/(m2 h). In this case, the underflow concentration of thickener is relatively high, which is 64.92-65.78%, and the solid content of overflow water is less than 164 ppm. The conventional full tailings thickening process was improved by using the design of high-efficiency deep cone thickener and vertical sand silo. The feasibility of fine-grained tailings as filling aggregate was demonstrated by combining the filling ratio test of fine-grained tailings, the data of thickening test and the improved thickening process. The research results can provide reference for other mines to use fine-grained tailings as filling aggregate to design filling system.

Associations between Lesion Locations and Stroke Recurrence in Survivors of First-ever Ischemic Stroke: A Prospective Cohort Study.

Several studies have indicated that stroke survivors with multiple lesions or with larger lesion volumes have a higher risk of stroke recurrence. However, the relationship between lesion locations and stroke recurrence is unclear. We conducted a prospective cohort study of first-ever ischemic stroke survivors who were consecutively enrolled from January 2010 to December 2015. Stroke recurrence was assessed every 3 months after post-discharge via telephone interviews by trained interviewers. Lesion locations were obtained from hospital-based MRI or CT scans and classified using two classification systems that were based on cerebral hemisphere or vascular territory and brain anatomical structures. Flexible parametric survival models using the proportional hazards scale (PH model) were used to analyze the time-to-event data. Among 633 survivors, 63.51% (n=402) had anterior circulation ischemia (ACI), and more than half of all ACIs occurred in the subcortex. After a median follow-up of 2.5 years, 117 (18.48%) survivors developed a recurrent stroke. The results of the multivariate PH model showed that survivors with non-brain lesions were at higher risk of recurrence than those with right-side lesions (HR, 2.79; 95%CI, 1.53, 5.08; P=0.001). There was no increase in risk among survivors with left-side lesions (HR, 0.97; 95%CI, 0.53, 1.75; P=0.914) or both-side lesions (HR, 1.24; 95%CI, 0.75, 2.07; P=0.401) compared to those with right-side lesions. Additionally, there were no associations between stroke recurrence and lesion locations that were classified based on vascular territory and brain anatomical structures. It was concluded that first-ever ischemic stroke survivors with non-brain lesion had higher recurrence risk than those with right-side lesion, although no significant associations were found when the lesion locations were classified by vascular territory and brain anatomical structures.

Carbohydrate profiling in seeds and seedlings of transgenic triticale modified in the expression of sucrose:sucrose-1-fructosyltransferase (1-SST) and sucrose:fructan-6-fructosyltransferase (6-SFT).

Constructs with sucrose-sucrose 1-fructosyltransferase (1-SST) from rye and or sucrose-fructan 6-fructosyltransferase (6-SFT) from wheat were placed under the control of wheat aleurone-specific promoter and expressed in triticale using biolistic and microspore transformation. Transgenic lines expressing one or both the 1-SST and the 6-SFT accumulated 50% less starch and 10-20 times more fructan, particularly 6-kestose, in the dry seed compared to the untransformed wild-type (WT) triticale; other fructans ranged in size from DP 4 to DP 15. During germination from 1 to 4 days after imbibition (dai), fructans were rapidly metabolized and only in transgenic lines expressing both 1-SST and 6-SFT were fructan contents significantly higher than in the untransformed controls after 4 days. In situ hybridization confirmed expression of 6-SFT in the aleurone layer in imbibed seeds of transformed plants. When transgenic lines were subjected to a cold stress of 4°C for 2 days, synthesis of fructan increased compared to untransformed controls during low-temperature germination. The increase of fructan in dry seed and germinating seedling was generally associated with transcript expression levels in transformed plants but total gene expression was not necessarily correlated with the time course accumulation of fructan during germination. This is the first report of transgenic modification of cereals to achieve production of fructans in cereal seeds and during seed germination.