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Black polyimides (BPIs) have gained increasing attention because of their growing demands in optoelectronic areas. However, the commonly used BPI containing carbon black suffers from the decreases of mechanical and electrical performances. In this work, a soluble intrinsic BPI (TPCPDFPPI) was prepared by the reaction of 4,4′‐(hexafluoroisopropylidene) diphthalic anhydride (6FDA) and a new diamine (TPCPDFPDA) bearing tetraphenylcyclopentadienone (TPCP) connected with benzene and fluorene units. TPCP grafted with benzene and fluorene units acted as a chromophore that shifted the absorption range of PI toward the long‐wave direction. The resulting TPCPDFPPI possessed whole visible‐light absorption characteristic and therefore exhibited high blackness and opacity. Additionally, TPCPDFPPI displayed superior solubility, mechanical and electrical performance. Theoretical calculations exhibited that the visible‐light absorption responsible for the blackness of TPCPDFPPI was chiefly ascribed to the HOMO to LUMO electron transition in the diamines, where the electrons were primarily migrated from the 2,5‐position aryl groups to the cyclopentadienone. This work offers a promising strategy for improving the overall properties of BPIs for photo‐electronic areas. [ABSTRACT FROM AUTHOR]

The coronavirus disease 2019 (COVID‐19) pandemic posed great impacts on public health. To fight against the pandemic, robust immune responses induced by vaccination are indispensable. Previously, we developed a subunit vaccine adjuvanted by aluminum hydroxide, ZF2001, based on the dimeric tandem‐repeat RBD immunogen, which has been approved for clinical use. This dimeric RBD design was also explored as an mRNA vaccine. Both showed potent immunogenicity. In this study, a DNA vaccine candidate encoding RBD‐dimer was designed. The humoral and cellular immune responses induced by homologous and heterologous prime‐boost approaches with DNA‐RBD‐dimer and ZF2001 were assessed in mice. Protection efficacy was studied by the SARS‐CoV‐2 challenge. We found that the DNA‐RBD‐dimer vaccine was robustly immunogenic. Priming with DNA‐RBD‐dimer followed by ZF2001 boosting induced higher levels of neutralizing antibodies than homologous vaccination with either DNA‐RBD‐dimer or ZF2001, elicited polyfunctional cellular immunity with a TH1‐biased polarization, and efficiently protected mice against SARS‐CoV‐2 infection in the lung. This study demonstrated the robust and protective immune responses induced by the DNA‐RBD‐dimer candidate and provided a heterologous prime‐boost approach with DNA‐RBD‐dimer and ZF2001. [ABSTRACT FROM AUTHOR]

Brain oedema is a common pathological phenomenon following many diseases and may lead to severe secondary damage. Astrocytes are the most numerous cells in the brain. Five aquaporins (AQPs) have been found in mature astrocytes, which play crucial roles in water transportation. However, most studies have focused on AQP4 or AQP9 and whether another aquaporin such as AQP5 involved in brain oedema is unclear. Here, we addressed the issue that the expression pattern of AQP5 in rat astrocytes in vitro was altered in the hypotonic condition through some mitogen‐activated protein kinases (MAPK) pathways. Primary astrocytes were randomly divided into the control group and the hypotonic group. Cell viability was evaluated by MTT test. Immunofluorescence, Western blotting and real‐time PCR were used to detect the expression of AQP5. Western blotting was used to detect the variation of MAPK pathway. The present study demonstrated that incubation of astrocytes in the hypotonic medium produced an increase inAQP5 expression, and AQP5 peaked at 6–12 h after hypotension solution exposure. In addition, MAPK pathways were set in motion under hypotension, but not all branches. Only the p38 inhibitor can inhibit AQP5 expression in cultured astrocytes. AQP5 is directly related to the extracellular hypotonic stimuli in astrocytes, which could be regulated through the p38 MAPK pathway. [ABSTRACT FROM AUTHOR]

Cognitive dysfunction is one of the complications of diabetes. Unfortunately, there is no effective methods to block its progression currently. One of the pathophysiological mechanisms is synaptic protein damage and neuronal signal disruption because of glucose metabolism disorder. Dystroglycan protein, located in the post‐synaptic membrane of neurons, links the intracellular cytoskeleton with extracellular matrix. Abnormal expression of dystroglycan protein affects neuronal biological functions and leads to cognitive impairment. However, there are no relevant studies to observe the changes of β‐dystroglycan protein in diabetes rat brain and in primary neurons under high glucose exposure. Our data demonstrated the alterations of cognitive abilities in the diabetic rats; β‐dystroglycan protein degradation occurred in hippocampal and cortical tissues in diabetic rat brain. We further explored the mechanisms underlying of this phenomenon. When neurons are exposed to high glucose environment in long‐term period, microRNA‐132 (miR‐132) would be down‐regulated in neurons. Matrix Metalloproteinases‐9 (MMP‐9) mRNA, as a target of miR‐132, could be up‐regulated; higher expression and overlay activity of MMP‐9 protein could increase β‐DG protein degradation. In this way, β‐DG degradation may affect structure and functions among the synapses, which related to cognition decline. It may provide some theoretical basis for elucidating the molecular mechanism of diabetes‐induced cognitive dysfunction. [ABSTRACT FROM AUTHOR]

BACKGROUND: The cotton bollworm, Helicoverpa armigera (Hübner), and the beet armyworm, Spodoptera exigua (Hübner), are two major polyphagous lepidopteran pests of cultivated crops. They develop various levels of resistance to many frequently applied broad‐spectrum insecticides. Here, the larval susceptibilities of a laboratory population and six field‐collected populations per pest from Hunan Province, China to three insecticides were determined using a standard leaf‐dipping method in the laboratory. Field‐plot trials were conducted to verify the control efficacies of broflanilide 100 g L−1 suspension concentrate (SC), chlorantraniliprole 5% SC and emamectin benzoate 5.7% water‐dispersible granule, against H. armigera and S. exigua larvae using foliar sprays in 2013 and 2019. RESULTS: Variations among H. armigera and S. exigua field populations in their susceptibility levels to the three insecticides were observed in Linli, Yueyang and Changsha counties from 2013 to 2019. They were still high susceptibility to broflanilide only, but developed low and/or moderate levels of resistance to chlorantraniliprole and emamectin benzoate. In addition, broflanilide at 25 g ha−1 provided an excellent control efficacy of 81.92% to 96.46% against these pests during the 3–14‐days period after treatment in both years, whereas chlorantraniliprole at 50 g ha−1 and emamectin benzoate at 4.5 g ha−1 exhibited significantly decreased efficacies, which were consistent with their corresponding toxicity levels. CONCLUSIONS: These results suggest that broflanilide should be an important new tool for the effective control of diamide‐ and avermectin‐resistant H. armigera and S. exigua. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Our previous study has shown that PTEN-induced novel kinase 1 ( PINK1) knocking down significantly induced mitochondrial fragmentation. Although PINK1 is proved to be associated with autosomal recessive parkinsonism and its function in this chronic pathological process is widely studied, its role in acute energy crisis such as ischemic stroke is poorly known. In this study by employing an oxygen-glucose deprivation ( OGD) neuronal model, we explored the function of PINK1 in cerebral ischemia. Human PINK1, two PINK1 mutants W437X and K219M, or Pink1 sh RNA were transduced before OGD using lentiviral delivery. Our results showed that over-expression of wild-type PINK1 significantly ameliorated OGD induced cell death and energy disturbance including reduced ATP generation and collapse of mitochondrial membrane potential. PINK1 over-expression also reversed OGD increased mitochondrial fragmentation, and suppressed the translocation of the mitochondrial fission protein dynamin-related protein 1 (Drp1) from the cytosol to the mitochondria. Transduction of the mutant PINK1 failed to provide any protective effect, while knockdown of Pink1 significantly increased the severity of OGD-induced neuronal damage. Importantly, inhibition of Drp1 reversed the effects of knocking down Pink1 on neuronal death and ATP production in response to OGD. This study demonstrates that PINK1 prevents ischemic damage in neurons by attenuating mitochondrial translocation of Drp1, which maintains mitochondrial function and inhibits ischemia-induced mitochondrial fission. These novel findings implicate a pivotal role of PINK1 regulated mitochondrial dynamics in the pathology of ischemic stroke. [ABSTRACT FROM AUTHOR]

BACKGROUND: The function of cytochrome P450 proteins (P450s) in the metabolism of a variety of compounds by oxidation and reduction is well elucidated, but its interactions with other electron transfer components in the pyrethroid resistance of insect pests have been a mystery for a long time. In previous studies the authors cloned and characterised CYP6B7 and cytochrome b5 ( Cyt-b5) in the fenvalerate-resistant HDFR strain of cotton bollworm ( Helicoverpa armigera Hübner) and showed that CYP6B7 mRNA was overexpressed and important for resistance to fenvalerate. In the present study, the functional interactions of CYP6B7, NADPH-dependent cytochrome P450 reductase (CPR) and Cyt- b5 were assessed using RNA interference (RNAi) strategies and monitoring for fenvalerate resistance levels. RESULTS: RT-qPCR analyses indicated that the expression levels of CYP6B7, CPR and Cyt-b5 mRNA were decreased drastically in the midgut of fourth-instar larvae of the H. armigera HDFR strain after corresponding double-stranded RNA (dsRNA) injection, compared with that of the control. The knockdown of CYP6B7, CPR and Cyt-b5 transcripts was time course dependent during a 12-48 h period after dsRNA injection. At the earlier time points analysed, significant suppression of CYP6B7 mRNA levels was observed in larvae injected with dsCYP6B7-313 as compared with controls, and further suppression was observed in larvae injected with dsCYP6B7-313, dsCPR-403 and dsCyt-b5. The injection of dsCYP6B7-313 together with dsCPR-403 and dsCyt-b5 increased larval susceptibility of the HDFR strain to fenvalerate. CONCLUSION: The results demonstrated that silencing of CYP6B7 alone or CYP6B7 together with CPR and/or Cyt-b5 increased the susceptibility of H. armigera to fenvalerate, suggesting that CYP6B7, CPR and Cyt-b5 collaboratively participated in enhanced metabolism of fenvalerate and played an important role in the resistance of H. armigera to fenvalerate. Copyright © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

With plasma penetration into a capillary and the assistant of an air DBD, an ac‐driven Ar microplasma plume having a length of several cm is generated inside the capillary. The inner diameter of the capillary ranges from 4 to 100 µm. When the tube diameter decreases, the length of the microplasma plume decreases, and while the ignition voltage, the current density, and the electron density increase significantly. For the tube diameter of 9 µm, the current density and the electron density measured from the Stark broadening of Hα line reach as high as 109 A m−2 and 11 × 1016 cm−3, respectively. The microplasma plume is of high degree of ionization and remains non‐thermal. Rather than monotonically increasing, the propagation velocity of the microplasma plume decreases and then keeps almost unchanged after the tube diameter reaches 20 µm. The effects of the tube diameter in the range of 4–100 μm on the discharge ignition and the plasma properties of Ar microplasma plume are investigated. As the tube diameter decreases to 9 μm, the current density and the electron density reach up to 3.5× 109 A/m2 and 11 × 1016 cm−3, respectively. This study is beneficial to the miniature of the plasma jets for biomedical applications and surface modification. [ABSTRACT FROM AUTHOR]