Fine-scale spatial distribution of soil organic carbon and its fractions after afforestation with Pinus sylvestris and Salix psammophila in a semiarid desert of China

半干旱沙漠中樟子松和沙柳造林后土壤有机碳及其组分的小尺度空间分布 半干旱沙漠造林有助于改善土壤功能以及增加土壤有机碳(SOC)固定,但人们对造林后SOC及其不稳定(LOC)组分的小尺度空间分布了解甚少。本研究以毛乌素沙地东南缘樟子松(Pinus sylvestris)和沙柳 (Salix psammophila)为研究对象,量化了距离树体20、80、150和240 cm处SOC、LOC组分及其相关变量的小尺度空间分布。研究结果表明,沙柳和樟子松造林显著提高了SOC、总氮(TN)、可溶性有机碳 (DOC)、微生物碳(MBC)和易氧化有机碳(ROOC)含量;在距离树体20 cm处,0–100 cm土层樟子松SOC 储量比沙柳高27.21%;在距离树体80和150 cm处,沙柳SOC储量分别比樟子松高5.50%和5.66%;与流 沙地相比,在距离树体20、80、150 和240 cm处,沙柳和樟子松SOC储量显著增加了94.90%、39.50%、 27.10%和18.50%;沙柳和樟子松ROOC分别占SOC的14.09%和18.93%。总之,造林促进了半干旱流沙地SOC的积累,樟子松比沙柳分配更多的有机质到距离树体<80 cm范围内的土体中。     

Predictive value of protease-activated receptor-2 (PAR2) in cervical cancer metastasis

Metastasis is the primary cause of an unfavourable prognosis in patients with malignant cancer. Over the last decade, the role of proteinases in the tumour microenvironment has attracted increasing attention. As a sensor of proteinases, proteinase-activated receptor 2 (PAR₂) plays crucial roles in the metastatic progression of cervical cancer. In the present study, the expression of PAR₂ in multiple types of cancer was analysed by Gene Expression Profiling Interactive Analysis (GEPIA). Kaplan-Meier plotter was used to calculate the correlation between survival and the levels of PAR₂, Grb-associated binding protein 2(Gab2) and miR-125b. Immunohistochemistry (IHC) was performed to examine PAR₂ expression in a tissue microarray (TMA) of CESCs. Empower Stats was used to assess the predictive value of PAR₂ in the metastatic potential of CESC. We found that PAR₂ up-regulation was observed in multiple types of cancer. Moreover, PAR₂ expression was positively correlated with the clinicopathologic characteristics of CESC. miR-125b and its target Gab2, which are strongly associated with PAR₂-induced cell migration, are well-characterized as predictors of the prognostic value of CESC. Most importantly, the Cancer Genome Atlas (TCGA) data set analysis showed that the area under the curve (AUC) of the PAR₂ model was significantly greater than that of the traditional model (0.833 vs 0.790, P < .05), demonstrating the predictive value of PAR₂ in CESC metastasis. Our results suggest that PAR₂ may serve as a prognostic factor for metastasis in CESC patients.     

慈竹无性系种群能值特点及其影响能值计测因素的研究

 本文引用Harper(1977)的构件结构理论,从构件结构单位、无性系分株和无性系三个层次,对四川南充市郊慈竹无性系种群的能值特点及其影响能值的计测因素进行了定量研究。研究结果表明：慈竹无性系种群中,各构件单位的去灰分热值(AFCV)分别为：根15349.42J／g、根茎16372.92J／g、秆17106.06J／g、枝18111.99J／g和叶19451.90J／g;慈竹无性系分株的AFCV(J／g)随龄级增大而递增;慈竹无性系水平上的AFCV为：Ⅰ龄占16.47%、Ⅱ龄占25.76%、Ⅲ龄占36.32%、Ⅳ龄为13.08%及Ⅴ龄为8.37%。用恒容燃烧法测定热值时,其能值变化与氧分压密切相关。用经验公式计算的能值较作图法高;用AFCV表示能值较总干重热值(GCV)准确。     

Autophagic Impairment Contributes to Systemic Inflammation-Induced Dopaminergic Neuron Loss in the Midbrain

Background

Neuroinflammation plays an important role in the pathogenesis of Parkinson’s disease (PD), inducing and accelerating dopaminergic (DA) neuron loss. Autophagy, a critical mechanism for clearing misfolded or aggregated proteins such as α-synuclein (α-SYN), may affect DA neuron survival in the midbrain. However, whether autophagy contributes to neuroinflammation-induced toxicity in DA neurons remains unknown.

Results

Intraperitoneal injection of lipopolysaccharide (LPS, 5 mg/kg) into young (3-month-old) and aged (16-month-old) male C57BL/6J mice was observed to cause persistent neuroinflammation that was associated with a delayed and progressive loss of DA neurons and accumulation of α-SYN in the midbrain. The autophagic substrate-p62 (SQSTM1) persistently increased, whereas LC3-II and HDAC6 exhibited early increases followed by a decline. In vitro studies further demonstrated that TNF-α induced cell death in PC12 cells. Moreover, a sublethal dose of TNF-α (50 ng/ml) increased the expression of LC3-II, p62, and α-SYN, implying that TNF-α triggered autophagic impairment in cells.

Conclusion

Neuroinflammation may cause autophagic impairment, which could in turn result in DA neuron degeneration in midbrain.     

Circadian Yin-Yang Regulation and Its Manipulation to Globally Reprogram Gene Expression

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MiR-30-Regulated Autophagy Mediates Angiotensin II-Induced Myocardial Hypertrophy

Dysregulated autophagy may lead to the development of disease. Role of autophagy and the diagnostic potential of microRNAs that regulate the autophagy in cardiac hypertrophy have not been evaluated. A rat model of cardiac hypertrophy was established using transverse abdominal aortic constriction (operation group). Cardiomyocyte autophagy was enhanced in rats from the operation group, compared with those in the sham operation group. Moreover, the operation group showed up-regulation of beclin-1 (an autophagy-related gene), and down-regulation of miR-30 in cardiac tissue. The effects of inhibition and over-expression of the beclin-1 gene on the expression of hypertrophy-related genes and on autophagy were assessed. Angiotensin II-induced myocardial hypertrophy was found to be mediated by over-expression of the beclin-1 gene. A dual luciferase reporter assay confirmed that beclin-1 was a target gene of miR-30a. miR-30a induced alterations in beclin-1 gene expression and autophagy in cardiomyocytes. Treatment of cardiomyocytes with miR-30a mimic attenuated the Angiotensin II-induced up-regulation of hypertrophy-related genes and decreased in the cardiomyocyte surface area. Conversely, treatment with miR-30a inhibitor enhanced the up-regulation of hypertrophy-related genes and increased the surface area of cardiomyocytes induced by Angiotensin II. In addition, circulating miR-30 was elevated in patients with left ventricular hypertrophy, and circulating miR-30 was positively associated with left ventricular wall thickness. Collectively, these above-mentioned results suggest that Angiotensin II induces down-regulation of miR-30 in cardiomyocytes, which in turn promotes myocardial hypertrophy through excessive autophagy. Circulating miR-30 may be an important marker for the diagnosis of left ventricular hypertrophy.     

韭菜线粒体锰超氧化物歧化酶纯化及性质研究

经硫酸铵沉淀、ＤＥＡＥ－Ｓｅｐｈａｃｅｌ层析和Ｓｅｐｈａｄｅｘ Ｇ－２００凝胶过滤,将韭菜线粒体ＳＯＤ纯化到均一程度。从６０００ｇ韭菜叶片线粒体中纯化得到２．５ｍｇ酶,酶比活力达１２００Ｕ／ｍｇ蛋白。该酶对ＫＣＮ和Ｈ２Ｏ２都不敏感,热稳定性弱 外光区吸收峰在２８０ｎｍ,凝胶过滤法测得其分子量为８２００Ｄ,ＳＯＳ－ＰＡＧＥ法测定其亚基分子量的２２０００Ｄ,ＤＮＳ法测得其Ｎ－末端氨基酸为缬氨酸。上述结     

扬子鳄纹状体AChE、SOMmRNA阳性神经元的分布

目的 观察扬子鳄纹状体内乙酰胆碱酯酶（acetylcholinesterase,AChE）和生长抑素信使核糖核酸（somatostatin messenger ribonucleic acid,SOMmRNA）阳性神经元的形态和分布.方法 采用亚铁氰化酮法和原位杂交法观察扬子鳄纹状体内AChE和SOMmRNA阳性神经元的分布和特征.结果 扬子鳄纹状体内有AChE和SOMmRNA阳性神经元分布,两种神经元均有大、中、小型细胞,以中、小型细胞为主,神经元胞体呈圆形、椭圆形、三角形、梭形和多角形.结论 扬子鳄纹状体内有AChE和SOMmRNA阳性神经元分布.     

Genome‐wide analysis of Nilaparvata lugens nymphal responses to high‐density and low‐quality rice hosts

The brown planthopper (BPH) Nilaparvata lugens is an economically important pest on rice plants. In this study, the higher population density and yellow‐ripe stage of rice plants were used to construct adverse survival conditions (ASC) against BPH nymphs. Simultaneously, the low population density and tillering stage of rice plants were used to establish a suitable survival condition (SSC) as a control. Solexa/Illumina sequencing was used to identify genes of BPH nymphs responding to ASC. Significantly longer duration development of BPH nymphs and significantly lower brachypterous ratio of BPH adults were observed by ASC compared with SSC. A total of 2 544 differentially expressed genes (DEGs) were obtained and analyzed by BLASTx, Gene Ontology and KEGG Orthology. Gene ontology analysis revealed that the DEGs were mainly involved in categories of cell, cell part, cellular process, binding, catalytic, organelle and metabolic processes. 1 138 DEGs having enzyme commission numbers were assigned to different metabolic pathways. The largest clusters were neurodegenerative diseases (137, 12.0%), followed by carbohydrate metabolism (113, 9.9%), amino acid metabolism (94, 8.3%), nucleotide metabolism (76, 6.7%), energy metabolism (64, 5.6%), translation (60, 5.3%), lipid metabolism (58, 5.1%), and folding, sorting and degradation (52, 4.6%). Expressing profile of 11 DEGs during eight nymphal developmental stages of BPH were analyzed by quantitative real‐time polymerase chain reaction. The 11 genes exhibited differential expression between ASC and SSC during at least one developmental stage. The DEGs identified in this study provide molecular proof of how BPH reconfigures its gene expression profile to adapt to overcrowding and low‐quality hosts.