Impacts of Mild Hypothermia on LPS-Mediated TLR4/NF-κB Signaling Pathway in Microglia

Background: Existing studies have found that some inflammatory factors cause brain cell damage through the TLR4/NF-κB pathway, and that mild hypothermia has a protective effect on nerve cells. It is not clear whether the mild hypothermic brain protection is achieved through the TLR4/NF-κB pathway in microglia. Objective: To investigate the impacts of mild hypothermia on lipopolysaccharide (LPS)-mediated TLR4/NF-κB signaling pathway in microglia. Method: The cultured microglia cells in vitro were divided into the NS group and the LPS group at 33?C and 37?C, respectively;quantitative RT-PCR was performed to detect the expressions of TLR4 and NF-κB mRNA in the microglia, Western blot was used to detect the expressions of TLR4 and NF-κB protein in the microglia, and ELISA was performed to detect the levels of tumor necrosis factor α (TNF-α) and interleukin-10 (IL-10) in the culture medium. Results: Under the LPS stimulation, the mRNA and protein expressions of TLR4 and NF-κB at different time points had significant changes between the normothermia group and the mild hypothermia group, in which the expressions in the former group were firstly increased and then decreased, while those in the latter showed a continuous increasing trend (P < 0.01);and the expressions of TNF-α in all the groups presented the trend of first-increasing then-decreasing, while IL-10 exhibited one slow linear increasing trend (P Conclusions: Mild hypothermia could inhibit the mRNA and protein expressions of LPS-mediated TLR4/NF-κB signaling pathway in the microglia, and inhibit the production and release of downstream inflammatory cytokines (TNF-α and IL-10).

Biodiversity, productivity, and temporal stability in a natural grassland ecosystem of China

Understanding the effect of biodiversity on ecosystem function is critical to promoting the sustainability of ecosystems and species conservation in natural ecosystems. We observed species composition, species richness and aboveground biomass,and simulated the competitive assemblages in a natural grassland ecosystem of China, aiming to test some assumptions and predictions about biodiversity–stability relationships. Our results show that aboveground productivity and temporal stability increased significantly with increasing species richness, and via a combination of overyielding, species asynchrony, and portfolio effects. Species interactions resulted in overyielding caused by trait-independent complementarity, and were not offset by a negative dominance effect and trait-dependent complementarity effect. Therefore, the mechanisms underlying the biodiversity effect shifted from the selection effect to the complementarity effect as diversity increased, and both effects were coexisted but the complementarity effect represent a mechanism that facilitates long term species coexistence in a natural grassland ecosystem of China.

Application of Simple Head Cooling Combined with Gangliosides in Neonatal Hypoxic-ischemic Encephalopathy

Objective To investigate the effect of simple head cooling combined with ganglioside therapy on neonatal hypoxic-ischemic encephalopathy(HIE)and its clinical efficacy.Methods A total of 100 children with HIE admitted in the neonatal ward of our hospital from August 2018 to October 2020 were selected as the research objects,and were divided into control group and observation group according to the random number table method,with 50 cases in each group.The control group was treated with gangliosides,and the observation group was treated with simple head cooling combined with gangliosides.Observe and compare the clinical performance improvement time,the level of relevant hematological examination indexes before and after treatment,and the neonatal behavioral neurological assessment(NBNA),clinical efficacy,and adverse reactions.Results The improvement time of convulsions,disturbance of consciousness,pupil changes,hypotonia,and gastrointestinal dysfunction in the observation group was significantly lower than that in the control group(all P<0.001).After treatment,the NSE,IL-6,CK,CK-MB of the two groups of children were significantly lower than before treatment,and the serum calcium and NBNA scores were significantly higher than before treatment,and the decrease or increase in the observation group was significantly higher than that of the control Group(all P<0.001).The total effective rate of treatment of children in the observation group(82.00%)was higher than that of the control group(62.00%)(P<0.05).There were no obvious adverse reactions in both groups.Conclusion The simple head cooling combined with gangliosides in the treatment of HIE can improve the clinical symptoms,blood test index levels,and NBNA scores.The clinical effect is clear and superior to the single use of gangliosides.

Fluorination reaction of UO_(3)and electrochemical preparation of UO_(2)

In this work,a technique was proposed to prepare UO_(2)from UO_(3)by the two processes of fluorination reaction of UO_(3)with NH_(4)HF_(2)and electrochemical reduction of UO_(2)^(2+)for the recycle uranium.The feasibility of fluorination reaction was firstly confirmed using thermodynamic calculation;then,the products were analyzed using XRD,Raman and fluorescence to be UO_(2)F_(2).The fluorination mechanism was inferred to be UO_(3)(s)+NH_(4)HF_(2)→(NH_(4))_(3)UO_(2)F_(5)→NH_(4)(UO_(2))_(2)F_(5)→UO_(2)F_(2).The redox behavior of UO_(2)^(2+)on W electrode was investigated by cyclic voltammetry and square wave voltammetry,which indicated that UO_(2)^(2+) was reduced to UO_(2)via a two-step single electron transfer with diffusion-controlled.The diffusion coefficient of UO_(2)^(2+) was calculated to be 6.22×10^(-5)cm/s.The disproportionation reaction of UO_(2)^(+) was observed,and the relationship between the disproportionation reaction and scan rate was discussed.Moreover,the electrochemical fabrication of UO_(2) was conducted by electrolysis at-0.8 V,and the product was analyzed by XRD,SEM and EDS to be UO_(2).ICP-AES results showed that the extraction efficiency of UO_(2) could reach 98.53%.