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991.
Dysfunction of glutamate neurotransmission in the nucleus accumbens (NAc) has been implicated in the pathophysiology of alcohol use disorders (AUD). Neurogranin (Ng) is exclusively expressed in the brain and mediates N‐methyl‐d ‐aspartate receptor (NMDAR) hypo‐function by regulating the intracellular calcium‐calmodulin (Ca2+‐CaM) pathway. Ng null mice (Ng–/– mice) demonstrate increased alcohol drinking compared to wild‐type mice, while also showing less tolerance to the effect of alcohol. To identify the molecular mechanism related to alcohol seeking, both in vivo microdialysis and label‐free quantification proteomics comparing Ng genotype and effects of alcohol treatment on the NAc are utilized. There is significant difference in glutamate and gamma‐aminobutyric acid (GABA) neurotransmission between genotypes; however, alcohol administration normalizes both glutamate and GABA levels in the NAc. Using label‐free proteomics, 427 protein expression changes are identified against alcohol treatment in the NAc among 4347 total proteins detected. Bioinformatics analyses reveal significant molecular differences in Ng null mice in response to acute alcohol treatment. Ingenuity pathway analysis found that the AKT network is altered significantly between genotypes, which may increase the sensitivity of alcohol in Ng null mice. The pharmacoproteomics results presented here illustrate a possible molecular basis of the alcohol sensitivity through Ng signaling in the NAc.  相似文献   
992.
The relationship between oxidants and organismal aging was first articulated through the free radical theory of aging. One of the major predictions of the free radical theory of aging is that oxidative stress shortens organisms’ lifespan because of an increased level of oxidants, which are damaging to macromolecules. However, challenging the role of oxidants in age‐related diseases, there is now sufficient evidence that antioxidant supplements do not provide significant health benefits. Interestingly, in addition to an increase in oxidant‐mediated macromolecules damage, there is convincing experimental data to support the role of senescent cells in the process of aging. Here, the current knowledge regarding the role of oxidants and cellular senescence in organismal aging is reviewed and it is proposed that, in addition to the role of oxidants as inducers of macromolecular damage, oxidants may also function as regulators of signaling pathways involved in the establishment of cellular senescence. If this role for oxidants is established, it may be necessary to modify the free radical theory of aging from “Organisms age because cells accumulate reactive oxygen species‐dependent damage over time” to: “Organisms age because cells accumulate oxidants’‐dependent damage and oxidants’‐dependent senescent characteristics over time.”  相似文献   
993.
Cancer research is striving toward new frontiers of assigning the correct personalized drug(s) to a given patient. However, extensive tumor heterogeneity poses a major obstacle. Tumors of the same type often respond differently to therapy, due to patient‐specific molecular aberrations and/or untargeted tumor subpopulations. It is frequently not possible to determine a priori which patients will respond to a certain therapy or how an efficient patient‐specific combined therapy should be designed. Large‐scale datasets have been growing at an accelerated pace and various technologies and analytical tools for single cell and bulk level analyses are being developed to extract significant individualized signals from such heterogeneous data. However, personalized therapies that dramatically alter the course of the disease remain scarce, and most tumors still respond poorly to medical care. In this review, the basic concepts of bulk and single cell approaches are discussed, as well as their emerging role in individualized designs of drug therapies, including the advantages and limitations of their applications in personalized medicine.  相似文献   
994.
Brewers’ spent grain (BSG) is a low‐cost by‐product of the brewing process. BSG liquor names the liquid components of BSG, mainly glucose, maltose, and long‐chain α‐1,4‐glycosidic bond glucose oligomers. These substances should be separated in existing BSG biorefineries, as they might lead to an increased formation of microbe‐inhibiting compounds in well‐established hydrothermal/enzymatic saccharification processes. In most cases, this liquid fraction is discarded. The present study presents for the first time an optimized process with BSG liquor for the purpose of producing bulk chemicals (e.g., lactate) in relevant concentrations. The process comprises the application of yeast extract, produced from own brewing processes, as the sole supplemented complex constituent in a simultaneous fermentation and saccharification process. Kinetic parameters for the final optimized process conditions with the organism Lactobacillus delbrueckii subsp. lactis were: maximum specific growth rate µmax  =  0.47 h?1, maximum lactate concentration cLac, max  =  79.06 g L?1, process yield YPS  =  0.89 gLac gSugar?1, lactate production rate qP  =  4.18 gLac gCDW?1 h?1, and productivity P 15 h  =  4.93 gLac L?1 h?1. BSG liquor, linked with yeast extract from Brewers’ yeast, can be a promising substrate for further bioprocess engineering tasks and contribute to a holistic and sustainable usage of Brewers’ spent grain.  相似文献   
995.
It is known that interfaces have various impacts on crystallization from a solution. Here, we describe crystallization of acetaminophen using a microflow channel, in which two liquids meet and form a liquid–liquid interface due to laminar flow, resulting in uniform mixing of solvents on the molecular scale. In the anti‐solvent method, the microflow mixing promoted the crystallization more than bulk mixing. Furthermore, increased flow rate encouraged crystal formation, and a metastable form appeared under a certain flow condition. This means that interface management by the microchannel could be a beneficial tool for crystallization and polymorph control.  相似文献   
996.
997.
QTL pyramiding for producing nutritious and safe rice grains   总被引:1,自引:0,他引:1  
正Breeding of rice varieties that are enriched with essential micronutrients and simultaneously have reduced levels of toxic elements in grains is largely unexplored in rice breeding practice. In this issue of JIPB, Liu et al.(2020)developed two rice lines with a low level of cadmium and simultaneously high levels of zinc or selenium accumulation in the grains, thus providing elite genetic materials for breeding rice varieties that are important for addressing mineral malnutrition and ensuring food safety.m entary  相似文献   
998.
Plants depend on gravity to provide the constant landmark for downward root growth and upward shoot growth. The phytohormone auxin and its cell‐to‐cell transport machinery are central determinants ensuring gravitropic growth. Statolith sedimentation toward gravity is sensed in specialized cells. This positional cue is translated into the polar distribution of PIN auxin efflux carriers at the plasma membrane, leading to asymmetric auxin distribution and consequently, differential growth and organ bending. While we have started to understand the general principles of how primary organs execute gravitropism, we currently lack basic understanding of how lateral plant organs can defy gravitropic responses. Here we briefly review the establishment of the oblique gravitropic set point angle in lateral roots and particularly discuss the emerging role of asymmetric cytokinin signaling as a central anti‐gravitropic signal. Differential cytokinin signaling is co‐opted in gravitropic lateral and hydrotropic primary roots to counterbalance gravitropic root growth.  相似文献   
999.
Imitation Switch (ISWI) chromatin remodelers are known to function in diverse multi‐subunit complexes in yeast and animals. However, the constitution and function of ISWI complexes in Arabidopsis thaliana remain unclear. In this study, we identified forkhead‐associated domain 2 (FHA2) as a plant‐specific subunit of an ISWI chromatin‐remodeling complex in Arabidopsis. By in vivo and in vitro analyses, we demonstrated that FHA2 directly binds to RLT1 and RLT2, two redundant subunits of the ISWI complex in Arabidopsis. The stamen filament is shorter in the fha2 and rlt1/2 mutants than in the wild type, whereas their pistil lengths are comparable. The shorter filament, which is due to reduced cell size, results in insufficient pollination and reduced fertility. The rlt1/2 mutant shows an early‐flowering phenotype, whereas the phenotype is not shared by the fha2 mutant. Consistent with the functional specificity of FHA2, our RNA‐seq analysis indicated that the fha2 mutant affects a subset of RLT1/2‐regulated genes that does not include genes involved in the regulation of flowering time. This study demonstrates that FHA2 functions as a previously uncharacterized subunit of the Arabidopsis ISWI complex and is exclusively involved in regulating stamen development and plant fertility.  相似文献   
1000.
Polyamines are small aliphatic amines found in almost all organisms, ranging from bacteria to plants and animals. In most plants, putrescine, the metabolic precursor for longer polyamines, such as spermidine and spermine, is produced from arginine, with either agmatine or ornithine as intermediates. Here we show that Arabidopsis thaliana(Arabidopsis) arginine decarboxylase 1(ADC1), one of the two known arginine decarboxylases in Arabidopsis, not only synthesizes agmatine from arginine, but also converts N~δ-acetylornithine to N-acetylputrescine. Phylogenetic analyses indicate that duplication and neofunctionalization of ADC1 and NATA1, the enzymes that synthesize N~δ-acetylornithine in Arabidopsis, co-occur in a small number of related species in the Brassicaceae. Unlike ADC2, which is localized in the chloroplasts, ADC1 is in the endoplasmic reticulum together with NATA1, an indication that these two enzymes have access to the same substrate pool. Together, these results are consistent with a model whereby NATA1 and ADC1 together provide a pathway for the synthesis of N-acetylputrescine in Arabidopsis.  相似文献   
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