The interspecific competition presents greater nutrient facilitation compared with intraspecific competition through AM fungi interacting with litter for two host plants in karst soil

AM 真菌和枯落物互作下两种喀斯特植物种间竞争较种内竞争更能促进植物养分利用 枯落物是植物养分获取和土壤养分转化的关键载体。丛枝菌根(Arbuscular mycorrhizae, AM)对植物养分摄取的影响已被广泛认知。然而，在养分亏缺的喀斯特生境中，不同竞争方式的植物如何通过AM真菌和枯落物利用养分尚不清楚。本研究对两种喀斯特适生植物构树(Broussonetia papyrifera)和云贵鹅耳枥(Carpinus pubescens)进行种内竞争和种  间竞争种植处理，并通过幼套球 囊霉(Glomus etunicatum)接种或不接种处理，以及土壤中添加或不添加两物种叶片混合枯落物处理，测定了植物生物量以及氮、磷、钾浓度等指标，研究植物的生长和养分利用。研究结果表明，AM真菌对两种植物养分摄取影响不同，AM真菌显著提高了种内和种间竞争下构树的养分摄取量，但降低了云贵鹅耳枥的养分摄取量。种间竞争下接种AM真菌，枯落物添加促进了云贵鹅耳枥对氮的摄取，抑制了构树对氮的摄取。接种AM真菌和添加枯落物条件下，种间竞争的构树对氮、磷和钾的摄取量及云贵鹅耳枥对氮的摄取量均高于种内竞争；种间竞争下两物种养分竞争力呈现明显差异，即构树对磷和钾养分竞争力显著提高，对氮则不显著；云贵鹅耳枥仅对钾的养分竞争力显著降低，对氮和磷则无显著影响。这些结果说明，在AM真菌与枯落物相互作用下，两种喀斯特植物种间竞争较种内竞争更能促进植物养分利用。     

Metabolic Enzyme Alterations and Astrocyte Dysfunction in a Murine Model of Alexander Disease With Severe Reactive Gliosis

Alexander disease (AxD) is a rare and fatal neurodegenerative disorder caused by mutations in the gene encoding glial fibrillary acidic protein (GFAP). In this report, a mouse model of AxD (GFAP^Tg;Gfap^+/R236H) was analyzed that contains a heterozygous R236H point mutation in murine Gfap as well as a transgene with a GFAP promoter to overexpress human GFAP. Using label-free quantitative proteomic comparisons of brain tissue from GFAP^Tg;Gfap^+/R236H versus wild-type mice confirmed upregulation of the glutathione metabolism pathway and indicated proteins were elevated in the peroxisome proliferator-activated receptor (PPAR) signaling pathway, which had not been reported previously in AxD. Relative protein-level differences were confirmed by a targeted proteomics assay, including proteins related to astrocytes and oligodendrocytes. Of particular interest was the decreased level of the oligodendrocyte protein, 2-hydroxyacylsphingosine 1-beta-galactosyltransferase (Ugt8), since Ugt8-deficient mice exhibit a phenotype similar to GFAP^Tg;Gfap^+/R236H mice (e.g., tremors, ataxia, hind-limb paralysis). In addition, decreased levels of myelin-associated proteins were found in the GFAP^Tg;Gfap^+/R236H mice, consistent with the role of Ugt8 in myelin synthesis. Fabp7 upregulation in GFAP^Tg;Gfap^+/R236H mice was also selected for further investigation due to its uncharacterized association to AxD, critical function in astrocyte proliferation, and functional ability to inhibit the anti-inflammatory PPAR signaling pathway in models of amyotrophic lateral sclerosis (ALS). Within Gfap⁺ astrocytes, Fabp7 was markedly increased in the hippocampus, a brain region subjected to extensive pathology and chronic reactive gliosis in GFAP^Tg;Gfap^+/R236H mice. Last, to determine whether the findings in GFAP^Tg;Gfap^+/R236H mice are present in the human condition, AxD patient and control samples were analyzed by Western blot, which indicated that Type I AxD patients have a significant fourfold upregulation of FABP7. However, immunohistochemistry analysis showed that UGT8 accumulates in AxD patient subpial brain regions where abundant amounts of Rosenthal fibers are located, which was not observed in the GFAP^Tg;Gfap^+/R236H mice.     

SP3-Enabled Rapid and High Coverage Chemoproteomic Identification of Cell-State–Dependent Redox-Sensitive Cysteines

Proteinaceous cysteine residues act as privileged sensors of oxidative stress. As reactive oxygen and nitrogen species have been implicated in numerous pathophysiological processes, deciphering which cysteines are sensitive to oxidative modification and the specific nature of these modifications is essential to understanding protein and cellular function in health and disease. While established mass spectrometry-based proteomic platforms have improved our understanding of the redox proteome, the widespread adoption of these methods is often hindered by complex sample preparation workflows, prohibitive cost of isotopic labeling reagents, and requirements for custom data analysis workflows. Here, we present the SP3-Rox redox proteomics method that combines tailored low cost isotopically labeled capture reagents with SP3 sample cleanup to achieve high throughput and high coverage proteome-wide identification of redox-sensitive cysteines. By implementing a customized workflow in the free FragPipe computational pipeline, we achieve accurate MS1-based quantitation, including for peptides containing multiple cysteine residues. Application of the SP3-Rox method to cellular proteomes identified cysteines sensitive to the oxidative stressor GSNO and cysteine oxidation state changes that occur during T cell activation.     

Arabica coffee and olive oils mitigate malathion-induced nephrotoxicity in rat: In silico,immunohistochemical and biochemical evaluation

Malathion (MAL) is an organophosphate insecticide that disrupts the body's antioxidant system; it is one of the earliest organophosphate insecticides extensively used as dust, emulsion, and vapor control a wide variety of insect pests under different conditions. This experimentation aims to evaluate the influence of Arabica coffee oil and olive oil on MAL-induced nephrotoxicity in male rat. 6 sets bearing the same number of animals were applied to this experiment. Each set comprised 10 rats. The first set of rats was used as the control group; rats in the second set were exposed to MAL measured at 100 mg/kg body weight for 7 weeks. Animals in the third and fourth set were treated with 400 mg/kg body weight of Arabica coffee oil and olive oil, and 100 mg/kg body weight of MAL. The fifth, together with the sixth set, were fed with a similar proportion of Arabica coffee oil and olive oil as administered to the third set of rats. After the experimental duration, rats of group 2 showed severe biochemical alterations, including significant increases of creatinine, uric acids, and urea nitrogen (BUN), resulting in marked decreases in serum albumin values and total protein (TP). Severe histopathological and immunohistochemical alterations of kidney tissues were observed in exposed MAL-intoxicated rats. Administration of these oils reduced the detected biochemical, histopathological modifications caused by MAL intoxication. Two active ingredients in Arabica coffee oil (oleic acid) and olive oil (hydroxytyrosol) showed good cyclooxygenase-2 (COX 2) interaction. Moreover, oleic acid from coffee oil and olive oil exhibited impressive association with xanthine oxidase (XO). The current finding showed that coffee oil and olive oil could be appraised as possible and a likely deterrence component against nephrotoxicity brought about by MAL.     

Tissue-Characteristic Expression of Mouse Proteome

The mouse is a valuable model organism for biomedical research. Here, we established a comprehensive spectral library and the data-independent acquisition–based quantitative proteome maps for 41 mouse organs, including some rarely reported organs such as the cornea, retina, and nine paired organs. The mouse spectral library contained 178,304 peptides from 12,320 proteins, including 1678 proteins not reported in previous mouse spectral libraries. Our data suggested that organs from the nervous system and immune system expressed the most distinct proteome compared with other organs. We also found characteristic protein expression of immune-privileged organs, which may help understanding possible immune rejection after organ transplantation. Each tissue type expressed characteristic high-abundance proteins related to its physiological functions. We also uncovered some tissue-specific proteins which have not been reported previously. The testis expressed highest number of tissue-specific proteins. By comparison of nine paired organs including kidneys, testes, and adrenal glands, we found left organs exhibited higher levels of antioxidant enzymes. We also observed expression asymmetry for proteins related to the apoptotic process, tumor suppression, and organ functions between the left and right sides. This study provides a comprehensive spectral library and a quantitative proteome resource for mouse studies.     

接种丛枝菌根真菌对云南石漠化土壤呼吸的影响

为探明"丛枝菌根（Arbuscular mycorrhiza，AM）真菌-植物-土壤"耦合作用对石漠化土壤呼吸季节动态的影响，采用LI-6400-09土壤呼吸室和便携式光合作用测量系统，对圆柏（Sabina chinensis）接种摩西斗管囊霉（Funneliformis mosseae，FM）、根内根孢囊霉（Rhizophagus intraradices，RI）2种AM菌种处理下土壤呼吸季节动态进行野外连续定位观测，并探究AM真菌接种处理下石漠化土壤呼吸速率与植物生长、土壤理化性质之间的关系。结果表明：（1）相较于对照，接种AM真菌对石漠化生境土壤呼吸季节动态产生了显著影响（P<0.01）。AM真菌处理具有较高的土壤呼吸季节变化幅度，即根内根孢囊霉处理土壤呼吸速率（1.55-9.10 μmol m^-2 s^-1）显著高于摩西斗管囊霉（1.62-8.29 μmol m^-2 s^-1）和对照（1.23-4.46 μmol m^-2 s^-1）；（2） AM真菌接种处理下土壤温湿度变化对土壤呼吸的影响显著大于对照，即土壤温度与水分对土壤呼吸的平均解释量大小顺序为：RI （44.84%；52.35%）>FM （17.18%；41.65%）>CK （2.66%；16.55%）；（3）2种菌种处理下土壤呼吸速率均与土壤有机质、硝态氮、全氮、速效钾、树高、胸径及根系生物量呈显著或极显著正相关（P<0.01或0.05），而与pH呈极显著负相关（P<0.01），但对照处理土壤呼吸速率除与pH呈显著负相关（P<0.05）外，与其它土壤理化指标相关性不显著；（4）土壤温度和水分、硝态氮、铵态氮、有机质、易氧化有机碳、速效钾、全氮及全磷对土壤呼吸变化的贡献最大，而胸径、树高、有效磷、微生物生物量、根系生物量及pH的影响次之。因此，"AM真菌-寄主植物-土壤"相互作用对石漠化生境土壤呼吸季节动态的影响，主要取决于不同AM真菌接种处理对土壤微气候（如含水量）、碳素（有机质、易氧化有机碳）、无机氮库（铵态氮、硝态氮）、根系生物量及磷钾养分可利用性的调控。     

Induction of bystander effects by UVA,UVB, and UVC radiation in human fibroblasts and the implication of reactive oxygen species

Radiation-induced bystander effects are various types of responses displayed by nonirradiated cells induced by signals transmitted from neighboring irradiated cells. This phenomenon has been well studied after ionizing radiation, but data on bystander effects after UV radiation are limited and so far have been reported mainly after UVA and UVB radiation. The studies described here were aimed at comparing the responses of human dermal fibroblasts exposed directly to UV (A, B, or C wavelength range) and searching for bystander effects induced in unexposed cells using a transwell co-incubation system. Cell survival and apoptosis were used as a measure of radiation effects. Additionally, induction of senescence in UV-exposed and bystander cells was evaluated. Reactive oxygen species (ROS), superoxide radical anions, and nitric oxide inside the cells and secretion of interleukins 6 and 8 (IL-6 and IL-8) into the medium were assayed and evaluated as potential mediators of bystander effects. All three regions of ultraviolet radiation induced bystander effects in unexposed cells, as shown by a diminution of survival and an increase in apoptosis, but the pattern of response to direct exposure and the bystander effects differed depending on the UV spectrum. Although UVA and UVB were more effective than UVC in generation of apoptosis in bystander cells, UVC induced senescence both in irradiated cells and in neighbors. The level of cellular ROS increased significantly shortly after UVA and UVB exposure, suggesting that the bystander effects may be mediated by ROS generated in cells by UV radiation. Interestingly, UVC was more effective at generation of ROS in bystanders than in directly exposed cells and induced a high yield of superoxide in exposed and bystander cells, which, however, was only weakly associated with impairment of mitochondrial membrane potential. Increasing concentration of IL-6 but not IL-8 after exposure to each of the three bands of UV points to its role as a mediator in the bystander effect. Nitric oxide appeared to play a minor role as a mediator of bystander effects in our experiments. The results demonstrating an increase in intracellular oxidation, not only in directly UV-exposed but also in neighboring cells, and generation of proinflammatory cytokines, processes entailing cell damage (decreased viability, apoptosis, senescence), suggest that all bands of UV radiation carry a potential hazard for human health, not only due to direct mechanisms, but also due to bystander effects.     

Drainage history and land use pattern of a Swedish river system — their importance for understanding nitrogen and phosphorus load

During the 19th and the first half of the 20th century, approximately 300 km² of lakes and wetlands, representing 29% of the River Kavlingean catchment in Southern Sweden, were drained to make land available for agriculture. Published accounts of nutrient loads from the catchment indicated that until the mid 20th century, factories and urban point sources were the major contributors of both nitrogen and phosphorus. By the middle of the 20th century, the construction of sewage treatment plants had effectively reduced phosphorus pollution. Concurrently, the land drained in the previous century underwent a more intense cultivation, with productivity being maintained by commercial fertilizers. Subsequently, net nutrient loads from agriculture continued to increase, reaching an annual load of 2652 tons total-nitrogen and 70 tons total-phosphorus for the River Kävlingeån. Whilst high nutrient leakage from agricultural watersheds may be a problem which is only recently recognized, it had its origins in nearly a hundred years of commonly accepted agricultural policy.To assess the importance of agriculture as the major source of nutrients to the River Kävlingeån system, three tributary catchment areas, differing in terms of their land use patterns (high, medium and low intensity of agricultural use), were studied and compared with literature figures. Results indicated that agricultural nutrient loss areal coefficients were substantially higher than the literature figures, demonstrating the role of agriculture as source of nutrients to the River Kävlingeån system. The agricultural land use policies of the last fifty years were revealed to be most important with regard to this role. Of such land use policies, the cultivation of the last 10–15% of land employed for agricultural use (primarily riparian ecotones) may be of most significance. The literature indicates that intense agricultural use of this final 10–15% may account for a ca. 50% increase in nitrogen loss. This suggests that one solution to the problem of agricultural diffuse pollution may lie in the restoration and sustainable management of riparian ecotones of agricultural streams.     

Field investigations of ammonia exchange between barley plants and the atmosphere. II. Nitrogen realiocation, free ammonium content and activities of ammonium-assimilating enzymes in different leaves

The activities of glutamine synthetase (GS) and glutamate synthase (GOGAT) in different leaves of field-grown spring barley were measured during the reproductive growth phase in 2 consecutive years. Concurrently, the contents of soluble ammonium ions and free amides in the leaves were determined. The studies were carried out to investigate the relationship between variations in these parameters and emission of NH3 from the plant foliage. GS and GOGAT activities declined very rapidly with leafage. The decline in enzyme activities was followed by an increase in soluble ammonium ions and amides in the leaf tissues. During the same period, about 75% of leaf and stem nitrogen was reallocated to the developing ear. The amount of NH₃ volatilized from the foliage during the reproductive growth phase amounted to about 1% of the reallocated nitrogen. The experimental years were characterized by very favourable conditions for grain dry matter formation and for re-utilization of nitrogen mobilized from leaves and stems. Ammonia volatilization occurring under conditions with declining GS and GOGAT activities and increasing tissue concentrations of NH₄⁺ may be useful in protecting the plant from accumulation of toxic NH₃ and NH₄⁺ concentrations in the tissues.