Sorghum rhizosphere effects reduced soil bacterial diversity by recruiting specific bacterial species under low nitrogen stress.

Rhizosphere microbiota play a pivotal role in promoting plant growth and defending against pathogens, but their responses to abiotic environmental stress remain largely elusive. Here, we investigated the influences of low-N stress on rhizosphere bacteria of six sorghum cultivars in a glasshouse experiment. The alpha diversity of bacteria (as revealed by Shannon diversity and Chao1 richness indices) was remarkably lower in rhizosphere soils than in bulk soils, and was significantly higher under low-N stress than under N addition. Principal coordinates analysis revealed that the bacterial community compositions in rhizosphere soils were clearly separated from bulk soils, and the rhizosphere soils under low-N stress or with N fertilization were clearly separated, indicating that both rhizosphere effects and N fertilization impacted the rhizosphere bacterial community. Notably, the relative abundances of beneficial bacteria such as Bacillaceae and Streptomycetaceae significantly increased in rhizosphere soils under low-N stress, which had significantly positive correlations with the sorghum N uptake. The relative abundance of Nitrosomonadaceae in rhizosphere soils was significantly lower than that in bulk soils, while the relative abundance of Rhizobiaceae showed an opposite pattern. Taken together, our results suggested that sorghum rhizosphere effects can reduce soil bacterial diversity possibly through recruiting specific bacterial species under low N stress.

[Effects of Osthole on Apoptosis of HL-60 Cells Induced by TRAIL and Its Related Mechanism].

OBJECTIVE: To explore the effects of Osthole on apoptosis of HL-60 cells induced by tumor necrosis factor related apoptosis inducing ligand (TRAIL) and its possible mechanism. METHODS: The proliferative inhibition of HL-60 cells treated with different concentrations of Osthole, TRAIL alone and Osthole combined with TRAIL was measured by MTT assay. The HL-60 cells were treated with Osthole, TRAIL alone and Osthole combined with TRAIL at the concentration

Complications and Prevention Strategies of Oblique Lateral Interbody Fusion Technique.

OBJECTIVE: To analyze the early complications and causes of oblique lateral interbody fusion, and put forward preventive measures. METHODS: There were 235 patients (79 males and 156 females) analyzed in our study from October 2014 to May 2017. The average age was 61.9 ± 0.21 years (from 32 to 83 years). Ninety-one cases were treated with oblique lateral interbody fusion (OLIF) alone (OLIF alone group) and 144 with OLIF combined with posterior pedicle screw fixation through the intermuscular space approach (OLIF combined group). In addition, 137/144 cases in the combined group were primarily treated by posterior pedicle screw fixation, while the treatments were postponed in 7 cases. There were 190 cases of single fusion segments, 11 of 2 segments, 21 of 3 segments, and 13 of 4 segments. Intraoperative and postoperative complications were observed. RESULTS: Average follow-up time was 15.6 ± 7.5 months (ranged from 6 to 36 months). Five cases were lost to follow-up (2 cases from the OLIF alone group and 3 cases from the OLIF combined group). There were 7 cases of vascular injury, 22 cases of endplate damage, 2 cases of vertebral body fracture, 11 cases of nerve injury, 18 cases of cage sedimentation or cage transverse shifting, 3 cases of iliac crest pain, 1 case of right psoas major hematoma, 2 cases of incomplete ileus, 1 case of acute heart failure, 1 case of cerebral infarction, 3 case of left lower abdominal pain, 9 cases of transient psoas weakness, 3 cases of transient quadriceps weakness, and 8 cases of reoperation. The complication incidence was 32.34%. Thirty-three cases occurred in the OLIF alone group, with a rate of 36.26%, and 43 cases in the group of OLIF combined posterior pedicle screw fixation, with a rate of 29.86%. Fifty-seven cases occurred in single-segment fusion, with a rate of 30.0% (57/190), 4 cases occurred in two-segment fusion, with a rate of 36.36% (4/11), 9 cases occurred in three-segment fusion, with a rate of 42.86% (9/21), and 6 cases occurred in four-segment fusion, with a rate of 46.15% (6/13). CONCLUSION: In summary, OLIF is a relatively safe and very effective technique for minimally invasive lumbar fusion. Nonetheless, it should be noted that OLIF carries the risk of complications, especially in the early stage of development.

[Effects of different crop rotations on growth of continuous cropping sorghum and its rhizosphere soil micro-environment.] / ä¸åŒä½œç‰©è½®ä½œå¯¹è¿žä½œé«˜ç²±ç”Ÿé•¿åŠå ¶æ ¹é™ åœŸå£¤çŽ¯å¢ƒçš„å½±å“.

The effects of crop rotation on sorghum [Sorghum biocolor (L) Moench] growth, rhizosphere microbial community and the activity of soil enzymes for successive crops of sorghum were evaluated. Five years of continuous monoculture sorghum as the control (CK) was compared to alfalfa and scallion planted in the fourth year. The results showed that incorporation of alfalfa and scallion into the rotation significantly improved sorghum shoot growth. Specifically, sorghum grain yield increased by 16.5% in the alfalfa rotation plots compared to the CK. The rotations also increased sorghum root system growth, with alfalfa or scallion rotation increasing sorghum total root length by 0.3 and 0.4 times, total root surface area by 0.6 and 0.5 times, root volume by 1.2 and 0.6 times, and root biomass by 1.0 and 0.3 times, respectively. Alfalfa rotation also expanded sorghum root distribution below the 10 cm soil depth. A Biolog analysis on biome functions in the sorghum flowering period indicated significantly higher microbial activity in the rotation plots. The alfalfa and scallion rotation increased the Shannon index by 0.2 and 0.1 times compared to the CK, and improved the sucrose activity in the rhizosphere soil. It was concluded that including alfalfa in rotation with sorghum improved sorghum rhizosphere soil environment, enhanced soil microbial enzyme activity, alleviated the obstacle of continuous cropping and thus increased the sorghum yield.

[Sensitization of human colon cancer HT-29 cells to TRAIL-induced apoptosis by gambognic acid].

To investigate the effects of gambognic acid (GA) on TRAIL-induced apoptosis of cancer cells, human colon HT-29 cancer cells were treated with GA to promote apoptosis. Inhibition of the cell proliferation was measured with MTT assay and cell apoptosis was detected with formation of DNA ladders in agarose gel electrophoresis, and activation of caspase activity. The content of cytosolic reactive oxygen species (ROS) was measured with flow cytometry. The activities of Caspase-3, -8, -9 were detected using spectrophotometric assay. The levels of c-FLIP, CHOP, DR4 and DR5 in cells were tested by Western blot. Combination of GA (1 µg · mL(-1)) and TRAIL (40 ng · mL(-1)) significantly reduced proliferation and increased apoptosis of HT-29 cells over those induced by each agent alone. Percentage of apoptotic cells was increased to 45.5%. GA markedly enhanced the intracellular ROS generation. Expression of CHOP, DR4 and DR5 was up-regulated to 7.38, 5.41, and 4.85 times of the control group, respectively. GA promoted activation of Caspase-3, -8, and -9 by TRAIL (P<0.05). Furthermore, the expression of anti-apoptotic protein c-FLIP was down-regulated to 0.22 ± 0.08 times of the control group. In conclusion, GA sensitizes HT-29 cells to TRAIL-induced apoptosis by promoting ROS-activated ERS pathways, up-regulating of DR4 and DR5, and inhibiting c-FLIP expression.

[Cadmium induced apoptosis of HEK293 cells and its mitochondrial apoptosis pathway].

HEK293 cell was chose to study the kidney damage of cadmium and to explore the significance of caspase 3,Bcl-2 and AIF (apoptosis inducing factor) in the apoptosis of cells induced by cadmium. Inhibition of the cell proliferation was measured by MTT assay. The structure of apoptotic cells was observed by light microscopy and electron microscopy; moreover, apoptotic cells were detected by DNA electrophoresis, flow cytometry and confocal laser microscopy. Furthermore,the expressions of Pro-caspase-3, Bcl-2 and the location of AIF in cells (mitochondria,cytoplasm or nuclei) were tested by western blot and immunofluorescence assay. CdCl2 exhibited anti-proliferative activity in dosage and time-dependent manner. DNA ladders of HEK293 cells were showed on agarose gel electrophoresis and the fragments of DNA were integral of 180-200 bp. 6-9 hours after 30 micromol/L CdCl2 treatment,DNA ladders were distinct. However, mistiness DNA ladder or smear was found when HEK293 cells were treated with CdCl2 on higher concentration or treated longer. It suggests that necrosis may happen, and flow cytometry results confirmed it. Morphological examination showed cell shrinkage, chromosomal condensation, karyotheca margination, nucleus cracking, vacuoles formed in cytoplasm and the presence of apoptotic bodies. At the same time,mitochondrial membrane potential (MMP) decreased, and the expression of Pro-caspase-3, Bcl-2 were decreased in time-dependent manner. Furthermore, AIF was released from mitochondria,and then traveled to nuclei. It suggests that CdCl2 may induce the apoptosis of HEK293 cells involving mitochondrial disruption including AIF migration and Cyt c release through both caspase-independent and -dependent pathways, and Bcl-2 and Caspase-3 are important factors which participate in the processes.

Cadmium-induced apoptosis in human normal liver L-02 cells by acting on mitochondria and regulating Ca(2+) signals.

Cadmium is a well-known toxic compound for the liver. It has been demonstrated to induce hepatotoxicity partly via apoptosis, but no uniform mechanism of apoptosis has so far been proposed. This study was first to determine whether cadmium-induced apoptosis in L-02 cells, second to observe the mechanism of cadmium-induced apoptosis. Studies of morphology, DNA fragmentation and apoptotic rate demonstrated that 60µM cadmium induced apoptosis with strong effects on cell viability. A concomitant time-dependent decrease of Bcl-2 and mitochondrial transmembrane potential (ΔΨ(m)) was observed. Subsequently, increase of caspase-3 activity and release of mitochondrial AIF were detected. However, cell pretreatment with a broad-specificity caspase inhibitor (Z-Asp) did not abolish apoptosis. These data demonstrated that the apoptotic events involved a mitochondria-mediated apoptotic pathway but not necessarily caspase-dependent signaling. On the other hand, intracellular free Ca(2+) concentration ([Ca(2+)](i)) of cadmium-exposed cells had significant increases and the Bapta-AM, a well-known calcium chelator, pretreatment partially blocked cadmium-induced apoptosis, indicating that the elevation of [Ca(2+)](i) may play an important role in the apoptosis. Together, these results support the notion that cadmium-induced hepatotoxicity is comparable to effects in L-02 by inducing apoptotic pathways on the basis of acting on mitochondria and regulating Ca(2+) signals.