[Effects of understory removal on soil microbial community composition in subtropical Phyllostachys edulis plantations]

We investigated the effects of understory removal on soil microbial community and soil physicochemical properties in a field experiment following random block design in subtropical moso bamboo (Phyllostachys edulis) plantations, which were widely contributed in middle subtropical area, aiming to assess the regulation mechanism of understory plants on soil microbial community. The results showed that understory removal significantly increased the contents of soil N, NO₃^--N, and soil available phosphorus, but decreased soil pH and the contents of soil NH₄⁺-N and soil phosphorus (TP). Moreover, understory removal decreased total and bacterial PLFAs (B) and increasing soil fungal PLFAs (F), resulting in a higher F/B ratio. Redundancy analysis showed that changes in fungal PLFAs caused by understory removal were mainly attributed to soil acidification, while changes in bacterial PLFAs caused by understory removal were mainly due to the decreases in soil TP and pH. Furthermore, i14:0、i15:0 and i16:0 contributed to the decreases in bacterial biomass. Our results suggested that understory removal might not be suitable for the management of subtropical P. edulis plantations, as it would alter microbial community composition. The shift of soil microbial community from bacteria to fungi could inhibit microbial decomposition function.

A Benziodoxole-Based Hypervalent Iodine(III) Compound Functioning as a Peptide Coupling Reagent

1-Benzoyloxy-1,2-benziodoxol-3-(1H)-one (IBA-OBz), a readily available and bench stable benziodoxole-based iodine(III) reagent, can be employed for the synthesis of dipeptides from various standard and sterically hindered amino acids in the presence of (4-MeOC₆H₄)₃P. The combined system of IBA-OBz/(4-MeOC₆H₄)₃P is also successfully applied to the solid-phase peptide synthesis and a pentapeptide leu-enkephalin in unprotected form has been synthesized. Density functional theory calculations reveal that the rate-limiting step is nucleophilic attack of 4-dimethylaminopyridine (DMAP) onto IBA-OBz.

[Resveratrol protects human sperm against cryopreservation-induced injury]

OBJECTIVE

To investigate the effects of resveratrol in the cryopreservation medium on the quality and function of post-thaw sperm.

METHODS

Semen samples were obtained from 50 normozoospermic and 50 oligoasthenozoospermic men, liquefied and then cryopreserved in the glycerol-egg yolk-citrate (GEYC) medium with or without 30 μmol/L resveratrol. Sperm motility, viability and acrosome reaction (AR) were examined before and after thawing. Sperm lipid peroxidation and the level of reactive oxygen species (ROS) were measured using commercial malondialdehyde (MDA) and the ROS assay kit. Sperm mitochondrial membrane potential (MMP) and DNA damage were determined by Rhodamine 123 staining and TUNEL.

RESULTS

The percentage of progressively motile sperm (PMS), total sperm motility, sperm viability, MMP and AR were significantly decreased (P <0.05) while the levels of sperm ROS, MDA and DNA fragmentation index (DFI) remarkably increased in both the normozoospermia and oligoasthenozoospermia groups after cryopreservation as compared with those in the fresh ejaculate (P <0.05). In comparison with the non-resveratrol control, the post-thaw sperm cryopreserved with 30 μmol/L resveratrol showed markedly higher PMS (［32.7 ± 4.8］ vs ［43.1 ± 6.3］ %, P <0.05), total motility (［44.8 ± 6.9］ vs ［56.9 ± 7.4］ %, P <0.05), viability (［52.3 ± 6.1］ vs ［67.5 ± 5.6］ %, P <0.05), MMP (［56.5 ± 7.0］ vs ［63.4 ± 7.5］ %, P <0.05) and AR (［16.6 ± 3.8］ vs ［26.3 ± 4.7］ %, P <0.05) but lower ROS, MDA and DFI (all P <0.05) in the normozoospermia group, and so did the post-thaw sperm in the oligoasthenozoospermia group, with a particularly lower DFI (［28.5 ± 4.8］ vs ［36.3 ± 5.7］%, P <0.01).

CONCLUSIONS

Resveratrol in the cryopreservation medium can improve the quality and function of post-thaw human sperm by reducing cryopreservation-induced sperm injury and the level of ROS.

Lentivirus‑mediated RIG‑I knockdown relieves cell proliferation inhibition, cell cycle arrest and apoptosis in ATRA‑induced NB4 cells via the AKT‑FOXO3A signaling pathway in vitro

Retinoic acid inducible gene I (RIG‑I) is upregulated during all‑trans retinoic acid (ATRA)‑induced terminal granulocytic differentiation of NB4 acute promyelocytic leukemia (APL) cells. However, the function and mechanism of RIG‑I in NB4 cells remains to be fully elucidated. In the present study, lentivirus‑mediated RIG‑I‑knockdown was used to investigate the proliferation, cell cycle and apoptotic processes of ATRA‑induced NB4 cells in vitro using an MTT assay and flow cytometry, respectively. The roles of RIG‑I and the AKT‑FOXO3A signaling pathway were investigated using western blot analysis. The results showed that the ATRA‑induced expression of RIG‑I was specifically and effectively knocked down at the mRNA and protein levels by lentivirus mediated RIG‑I short hairpin RNA. In addition, silencing of RIG‑I reduced the ATRA‑induced inhibition of NB4 cell proliferation, cell cycle arrest and apoptosis. Further investigations indicated that with ATRA‑induced expression of RIG‑I, levels of phosphorylated (p)AKT‑Thr308 and pForkhead Box (FOX) O3A‑Thr32 were decreased, the expression levels of cell cycle arrest protein p27 and the apoptotic protein, tumor necrosis factor‑related apoptosis‑inducing ligand (TRAIL), directly transcribed by FOXO3A were increased. By contrast, following the knockdown of ATRA‑induced expression of RIG‑I, the levels of pAKT‑Thr308 and pFOXO3A‑Thr32 were increased, and the protein expression levels of p27 and TRAIL were decreased. Taken together, these results showed that the knockdown of RIG‑I reduced the inhibition of cell proliferation, cell cycle arrest and apoptosis in the ATRA‑induced NB4 cells via the AKT‑FOXO3A signaling pathway.

[Non-linear compression for noises in non-contact vital signs detecting system]

A method for compressing the noises overlapping in the breath and heart signals of human beings, detected by the non-contact vital signs detecting system during the display of the waveforms in time domain, is discussed in this paper in detail. And what's more, the problem that the noise level is changed along with the increase of the gain of AD data-acquisition card and the display--gain of the software is solved by researching into the threshold of noise-level contraction in two types of circumstance in the lab, and the result of the breath and heart signal in the condition of lower noise is realized as well.

[The study on non-contact detection of breathing and heartbeat based on radar principles]

The paper introduces the design of hardware and software of non-contact detection system for breathing and heartbeat in human body with radar principles and technology. The detection technology is discussed. Under conditions of the illuminating power P < 1 mW and the distance S < 10 m, the non-contact breathing and heartbeat measurement, can be in different positions and with different clothing on the subject. The results show that the system with the technology has a high sensitivity, and is harmless to the health. It is a practicable non-contact detection technology for breathing and heartbeat of human body.