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  • Author: Hong Cheng-Yu x
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Abstract

In view of the current measurement of antenna array radiation phase characteristics, this paper proposes a method for measuring the radial phase characteristics of antenna array based on multi-channel CDMA excitation and multichannel CDMA receiving technique. The method using amplitude and phase can be adjusted precisely multiplexing code division multiple access (CDMA) signals as the antenna array each element incentive and use multi-channel receiver in the far field and receives, multipath CDMA signal separation, get the brightest point on the test signal is generated by the relative amplitude and phase characteristics of incentive, combined with antenna array position and structure, measuring point position information and measurement point synthetic field size and solve the antenna array radiation characteristic parameters. The simulation results show that this method can effectively measure the radial phase characteristics of the antenna array, and the method are more simple and direct than other methods.

A new taxoid metabolite with an unusual double bond between C-13 and C-14 was isolated from the methanol extract of the hard wood of Taxus cuspidata. The structure was established as 2α,5α,7β ,9α,10β ,13β -hexaacetoxy-11β -hydroxyl-19β -benzoxytaxa-4(20),13-dien- 12,16-epoxide (1), named 5,13-diacetyltaxinine M-13-enol, on the basis of spectral analysis including 1H NMR, 13C NMR, HMQC, HMBC, NOESY and confirmed by HR-FAB-MS.

Abstract

C18H21ClN2O3S, monoclinic, P21/c, a = 12.582(4) Å, b = 14.790(5) Å, c = 21.406(8) Å, β = 92.572(13)°, V = 3979(2) Å3, Z = 8, R gt (F) = 0.0464, wR ref (F 2 ) = 0.1298, T = 298(2) K.

Abstract

Background

Human bone marrow mesenchymal stem cells (BMSCs) are of great significance for bone regeneration and bone formation. Long non-coding RNAs (lncRNAs) may be involved in modulating cell differentiation. This study aimed to investigate the role of lncR-2271 in promoting osteogenic differentiation in human BMSCs.

Methods

Human BMSCs were infected using lncR-2271 overexpression (group A) with lentiviral system or transfected with lncR-2271 siRNA (group B). Cells transfected with scrambled plasmids were used as a negative control (group C). Osteogenesis markers were evaluated using alkaline phosphatase (ALP) activity, RUNX2 and osterix (OSX) at protein levels and calcification by Alizarin Red staining.

Results

BMSCs from group A showed significantly higher ALP activity compared to BMSCs in group B and control group (group C) at both days 7 and 14 following osteogenic induction; ALP activity was significantly lower in the group B compared to the group C. RUNX2 and OSX protein expressions were significantly higher in group A and significantly lower in group B, compared to those in group C, respectively. At day 21, calcification in human BMSCs in group A was significantly higher compared to groups B and C as shown by Alizarin Red staining; calcification was significantly lower in group B compared to group C.

Conclusion

Our data suggested lncR-2271 played a role in promoting osteogenic differentiation in human BMSCs. This study is the first to illustrate the important role of lncR-2271 in bone formation.

Abstract

Background: Retinal ganglion cells (RGCs) are protected in rats with acute elevated intraocular pressure (IOP) by Erigeron breviscapus (vant.) hand-mazz (EBHM). However, it is unclear whether EBHM has neuroprotective effect on RGCs in animal with chronic elevated IOP.

Objective: Investigate the protective effect of EBHM extract on RGCs in rabbits with chronic elevated IOP.

Methods: Unilateral chronic elevated IOP was produced in rabbits by repeated injection of 2% methylcellulose into the anterior chamber. Secondary degeneration was measured with and without EBHM extract treatment for 60 days. At 60 days, the cells density of the RGCs layer, the thickness of retinal nerve fiber layer (RNFL), and the optic nerve axons were observed and analyzed using an image analysis system. The ultrastructural changes of RGCs and optic nerve axons were observed using transmission electron microscopy.

Results: Compared with their contralateral control eyes with normal IOP, in the retinas of 3-4 mm from the optic disc, the cells density of the RGCs layer in the eyes with chronic elevated IOP was 23.2±6.5 cells (n = 6) and 36.0±8.9 cells (n = 10) per three 400x fields at 60 days in untreated and EBHM-treated group, respectively. The RNFL thickness in eyes with chronic elevated IOP was 3.4±0.4 μm (n = 6) and 5.0±1.0 μm (n = 10) at 60 days in untreated and EBHM-treated group, respectively. The axons number per 15057.8 μm2 in eyes with chronic elevated IOP was 370.4±41.0 (n = 6) and 439.0±50.8 (n = 10) at 60 days in untreated and EBHM-treated group, respectively. The number of the organelles in RGCs plasm appeared decreased and mitochondrion vacuolated in the elevated IOP eyes of EBHM-treated group, while some dispersive mitochondrion and rough surfaced endoplasmic reticulum and ribosome still existed in the RGCs plasm. The myelin sheath plates condensed and degenerated, and the microfilaments and microtubules decreased or disappeared in the elevated IOP eyes, but the axons degeneration in the chronic elevated IOP with EBHM treatment was less than that in the chronic elevated IOP without treatment.

Conclusion: EBHM extract provided a neuroprotective effect on retinal ganglion cells in rabbits with chronic elevated IOP.

Abstract

Introduction: A model of fatty liver in postpartum sheep was established to measure blood paraoxonase 1 (PON1) and other biochemical indicators, which were used to predict fatty liver in sheep.

Material and Methods: Sheep were assigned into two experimental groups: a fatty liver group (T, n = 10) and a healthy control group (C, n = 5). PON1 enzyme activity towards paraoxon as a substrate was quantified spectrophotometrically. The results were analysed by t-test and pearson correlation coefficient. Disease was predicted by binary logistic analysis, and diagnostic thresholds were determined by receiver operatingcharacteristic (ROC) analysis.

Results: The activity of serum PON1 in group T was significantly decreased (P < 0.05) when compared with C group, and liver lipid content and the levels of serum BHBA, NEFA, and TG were significantly increased (P < 0.05). Thresholds were lower than 74.0 U/mL for PON1, higher than 0.97 mmol/L for β-hydroxybutyrate, higher than 1.29 mmol/L for non-esterified fatty acids, higher than 0.24 mmol/L for triglycerides, and lower than 71.35 g/L for total protein.

Conclusion: This study verified that PON1, BHBA, NEFA, TG, and TP could be used to predict the risk of fatty liver in sheep.

Abstract

Introduction: The predictive value of selected parameters in the risk of ketosis and fatty liver in dairy cows was determined.

Material and Methods: In total, 21 control and 17 ketotic Holstein Friesian cows with a β-hydroxybutyrate (BHBA) concentration of 1.20 mmol/L as a cut-off point were selected. The risk prediction thresholds for ketosis were determined by receiver operating characteristic (ROC) curve analysis.

Results: In the ketosis group, paraoxonase-1 (PON-1) activity and concentration of PON-1 and glucose (GLU) were decreased, and aminotransferase (AST) activity as well as BHBA and non-esterified fatty acid (NEFA) contents were increased. The plasma activity and concentration of PON-1 were significantly positively correlated with the level of plasma GLU. The plasma activity and concentration of PON-1 were significantly negatively correlated with the levels of AST and BHBA. According to ROC curve analysis, warning indexes of ketosis were: plasma PON-1 concentration of 46.79 nmol/L, GLU concentration of 3.04 mmol/L, AST concentration of 100 U/L, and NEFA concentration of 0.82 mmol/L.

Conclusion: This study showed that the levels of PON-1, GLU, AST, and NEFA could be used as indicators to predict the risk of ketosis in dairy cows.

Abstract

C26H32N6NiO8, orthorhombic, Pbca (no. 61), a = 12.511(3) Å, b = 19.521(5) Å, c = 23.053(6) Å, V = 5630.2 Å3, Z = 8, Rgt(F) = 0.0541, wRref(F2) = 0.1570, T = 296 K.

Diabietane ether (1), a new abietane dimer connected by an ether linkage, and two known abietane diterpenoids (2 and 3) were isolated from the needles of Taxus cuspidata.

Abstract

Crystalline TiO2 nanoparticles were synthesized by hydrolysis of titanium (IV) isopropoxide (TTIP) in the docusate sodium salt (AOT) -cyclohexane microemulsion at controlled temperature. The influence of various reaction conditions, such as agitation speed (ε), [AOT]/[H2O] molar ratio (W), [TTIP]/[H2O] molar ratio (R), temperature (T), and aging (t) on the particle size were investigated. The nano-TiO2 particles were characterized for specific surface area (Brunauer-Emmett-Teller, BET) in addition to X-ray diffraction (XRD) and X-ray spectroscopy (XPS) as to determine the particle size, crystalline state, chemical composition, surface charge, and binding energy. The photocatalytic activity was assessed using methylene blue as probe. Results showed that the particle size was in the range from 13.7 to 31.4 nm based on BET measurements. The size of the particle grows with agitation speeds until log (ε) = 1.9; further increase in mixing rate caused particle breakup. In micelle solution, the particle size decreased with increase in W. In true solution the particle size increased with W. However, increase in R increased the particle size which reached a maximum value at a critical value of log R = -0.26, then decreased upon further increase in R. The activation energy (Ea) was calculated using Arrenhius plot and a value of -3.69 kJ/mol was obtained. Results of particle size analysis from XRD and BET were consistent with each other. Crystalline pattern was proved to be anatase. Furthermore, the photocatalytic activity appeared to optimum with particle size between 22.0 and 25.1 nm.