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As a widely discussed topic in Western academic circles, post-productionism has become an important background for studying China's three agricultural problems. By carefully analyzing the origin, development, and practice of post-productionism, this study reveals the conceptual connotations and research status of post-productionism, which has theoretical value and practical significance for the study of China's three agricultural problems. The research through the research method of philology and the analysis of CiteSpace, the representative foreign core journals in Wed of Science with the theme of "post-productionism" were selected and summarized on the basis of data analysis.The research draws the following results: 1) This paper introduces the origin of post-productionism and summarizes the existing problems of agricultural production, rural ecology, and farmers' survival during the crisis, as well as the social expectation of the linear transformation of productionism to post-productionism. 2) On the basis of comprehensive research on the concept of "post-productionism," the conceptual domain of post-productionism is constructed from the four aspects of farmer's role, agricultural policy, farming technology and environmental impact, and three stages of conceptual research are proposed: the opposite stage, the coexistence stage and the subjective perspective stage, and compares it with the concept of "multifunctional agriculture," and points out the value of "paradigm shift" represented by post-productionism. 3) Comparing the post-productive rural practices of developed and developing countries, analyzing the common factors and regional differences between the post-productive rural practices of developed countries, sorting out the "post-productive phenomenon" of developing countries, and explaining the research objectives and necessity. On this basis, The paper further responds to the key question whether there is consistency between the "de-agriculturalization" in developing countries and the "post-productionism" in developed countries, and points out that there are some differences between the two in development stage, concept difference, connotation extension, expression form and fundamental value orientation. The conclusions are as following: 1) The development concept of Post-productionism is a positive response to productionism crises. Under the integration of common concepts, its global development path reflects the characteristics of "time-space difference" and "nonlinear transformation." Productionism and post-productionism are not "opposites," but will coexist and influence each other as two types of agricultural and rural management systems for a long time. Attention should also be paid to the fundamental role of change at the microactor level. 2) In relation to specific national conditions, the enlightenment of post-productionism in China's three rural problems is that we should pay attention to the research and judgment and grasp the opportunity of rural development, combine the overall promotion with key breakthroughs, continue to adhere to industrial revitalization as the goal, build a solid foundation for agricultural development, focus on promoting the development of secondary and tertiary industries, and focus on industrial integration. It is also necessary to deeply explore the multidimensional value of rural space, enrich the spatial attributes of rural areas, and promote rural development and urban-rural integration.

Objectives: Repetitive transcranial magnetic stimulation (rTMS) has been considered as an effective antidepressant treatment; however, the mechanism of its antidepressant effect is still unclear. Fluoxetine, a selective serotonin reuptake inhibitor antidepressant, may be neuroprotective. The objective of the present study was to evaluate the effect and underlying possible neuroprotective mechanism of rTMS and fluoxetine on abnormal behaviours in a depressive mouse model induced by chronic unpredictable mild stress (CUMS).Methods: After 28 days of CUMS exposure, mice were chronically treated with rTMS (10 Hz for 5 s per train, total 20 trains per day) and (or) fluoxetine (5 mg/kg/day, intraperitoneally) for 28 days targeting on the frontal cortex. After the behavioural tests, the protein expressions of glial fibrillary acidic protein (GFAP), brain-derived neurotrophic factor (BDNF) and tyrosine kinase B (TrkB) were measured by immunohistochemistry and (or) Western Blot.Results: The results showed rTMS and (or) fluoxetine attenuated the locomotion decrease, anxiety and depressive like behaviours in the CUMS-exposed mice.Conclusion: Our results suggest that both rTMS and fluoxetine could benefit the CUMS-induced abnormal behaviours including depressive-like behaviours, and the beneficial effects of rTMS as well as fluoxetine on depression might be partly related to their neuroprotective effect on attenuating astroglial activation and BDNF decrease [ABSTRACT FROM AUTHOR]

C32H34N10O6S2Zn, monoclinic, C2/c (no. 15), a = 24.243(4) Å, b = 11.2766(17) Å, c = 15.799(5) Å, β = 127.986(2)°, V = 3404.0(13) Å3, Z = 4, Rgt(F) = 0.0432, wRref(F2) = 0.1146, T = 100(2) K.

Aminoacyl-tRNA protein transferases catalyze the post-translational addition of amino acids to proteins. The eubacterial leucyl/phenylalanyl-tRNA-protein transferase (L/F transferase) catalyzes the transfer of leucine or phenylalanine from their respective aminoacylated tRNAs to the N-termini of substrate proteins possessing an N-terminal lysine or arginine amino acid. Conventional assays to quantify L/F transferase activity involve measuring radioactive amino acid incorporation into substrate proteins. We have developed a quantitative matrix assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry procedure to measure the enzymatic activity of L/F transferase. The procedure utilizes stable isotope labeled substrate and internal standard peptides. The method is used to determine the kinetic parameters of [k.sub.cat] and [K.sub.m] for the enzymatic transfer of phenylalanine and three unnatural amino acid derivatives from an aminoacyl-tRNA to a peptide substrate.

Abstract Background Polyethyleneimine (PEI), which can interact with negatively charged DNA through electrostatic interaction to form nanocomplexes, has been widely attempted to use as a gene delivery system. However, PEI has some defects that are not fit for keeping on gene expression. Therefore, some modifications against PEI properties have been done to improve their application value in gene delivery. In this study, three modified PEI derivatives, including poly(ε-caprolactone)-pluronic-poly(ε-caprolactone) grafted PEI (PCFC-g-PEI), folic acid-PCFC-isophorone diidocyanate-PEI (FA-PEAs) and heparin-PEI (HPEI), were evaluated in terms of their cytotoxicity and transfection efficiency in vitro and in vivo in order to ascertain their potential application in gene therapy. Methods MTT assay and a marker GFP gene, encoding green fluorescent protein, were used to evaluate cell toxicity and transfection activity of the three modified PEI in vitro. Renal cell carcinoma (RCC) models were established in BALB/c nude mice inoculated with OS-RC-2 cells to detect the gene therapy effects using the three PEI-derived nanoparticles as gene delivery vehicles. The expression status of a target gene Von Hippel-Lindau (VHL) in treated tumor tissues was analyzed by semiquantitative RT-PCR and immunohistochemistry. Results Each of three modified PEI-derived biomaterials had an increased transfection efficiency and a lower cytotoxicity compared with its precursor PEI with 25-kD or 2-kD molecule weight in vitro. And the mean tumor volume was obviously decreased 30% by using FA-PEAs to transfer VHL plasmids to treat mice RCC models. The VHL gene expression was greatly improved in the VHL-treated group. While there was no obvious tumor inhibition treated by PCFC-g-PEI:VHL and HPEI:VHL complexes. Conclusions The three modified PEI-derived biomaterials, including PCFC-g-PEI, FA-PEAs and HPEI, had an increased transfection efficiency in vitro and obviously lower toxicities compared with their precursor PEI molecules. The FA-PEAs probably provide a potential gene delivery system to treat RCC even other cancers in future.

Abstract Background Heat shock proteins (HSPs), including mainly HSP110, HSP90, HSP70, HSP60 and small HSP families, are evolutionary conserved proteins involved in various cellular processes. Abnormal expression of HSPs has been detected in several tumor types, which indicates that specific HSPs have different prognostic significance for different tumors. In the current studies, the expression profiling of HSPs in human low-grade glioma tissues (HGTs) were investigated using a sensitive, accurate SILAC (stable isotope labeling with amino acids in cell culture)-based quantitative proteomic strategy. Results The five HSP family members were detected and quantified in both HGTs and autologous para-cancerous brain tissues (PBTs) by the SILAC-based mass spectrometry (MS) simultaneously. HSP90 AB1, HSP A5(70 KDa), and especially HSP27 were significantly downregulated in HGTs, whereas the expression level of HSPA9 (70 KDa) was little higher in HGTs than that in PBTs. It was noted that the downregulation ratio of HSP27 was 0.48-fold in HGTs versus PBTs, which was further validated by results from RT-PCR, western blotting and immunohistochemistry. Furthermore, we detected HSP27 expression changes along with cell growth under heat shock treatment in glioma H4 cells. Conclusion The SILAC-MS technique is an applicable and efficient novel method, with a high-throughput manner, to quantitatively compare the relative expression level of HSPs in brain tumors. Different HSP family members have specific protein expression levels in human low-grade glioma discovered by SILAC-MS analysis. HSP27 expression was obviously downregulated in HGTs versus PBTs, and it exhibited temporal and spatial variation under heat shock treatment (43°C/0-3 h) in vitro. HSP27's rapid upregulation was probably correlated with the temporary resistance to heat shock in order to maintain the survival of human glioma cells.

C32H34N10O6S2Zn, monoclinic, C2/c (no. 15), a = 24.243(4) Å, b = 11.2766(17) Å, c = 15.799(5) Å, β = 127.986(2)°, V = 3404.0(13) Å3, Z = 4, Rgt(F) = 0.0432, wRref(F2) = 0.1146, T = 100(2) K. [ABSTRACT FROM AUTHOR]

Background: Polyethyleneimine (PEI), which can interact with negatively charged DNA through electrostatic interaction to form nanocomplexes, has been widely attempted to use as a gene delivery system. However, PEI has some defects that are not fit for keeping on gene expression. Therefore, some modifications against PEI properties have been done to improve their application value in gene delivery. In this study, three modified PEI derivatives, including poly(ε-caprolactone)-pluronic-poly(ε-caprolactone) grafted PEI (PCFC-g-PEI), folic acid-PCFC-isophorone diidocyanate-PEI (FA-PEAs) and heparin-PEI (HPEI), were evaluated in terms of their cytotoxicity and transfection efficiency in vitro and in vivo in order to ascertain their potential application in gene therapy.Methods: MTT assay and a marker GFP gene, encoding green fluorescent protein, were used to evaluate cell toxicity and transfection activity of the three modified PEI in vitro. Renal cell carcinoma (RCC) models were established in BALB/c nude mice inoculated with OS-RC-2 cells to detect the gene therapy effects using the three PEI-derived nanoparticles as gene delivery vehicles. The expression status of a target gene Von Hippel-Lindau (VHL) in treated tumor tissues was analyzed by semiquantitative RT-PCR and immunohistochemistry.Results: Each of three modified PEI-derived biomaterials had an increased transfection efficiency and a lower cytotoxicity compared with its precursor PEI with 25-kD or 2-kD molecule weight in vitro. And the mean tumor volume was obviously decreased 30% by using FA-PEAs to transfer VHL plasmids to treat mice RCC models. The VHL gene expression was greatly improved in the VHL-treated group. While there was no obvious tumor inhibition treated by PCFC-g-PEI:VHL and HPEI:VHL complexes.Conclusions: The three modified PEI-derived biomaterials, including PCFC-g-PEI, FA-PEAs and HPEI, had an increased transfection efficiency in vitro and obviously lower toxicities compared with their precursor PEI molecules. The FA-PEAs probably provide a potential gene delivery system to treat RCC even other cancers in future. [ABSTRACT FROM AUTHOR]