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1.
Summary Protoplasts were isolated from cotyledons of 1- to 1.5-mo.-old seedlings ofChamaecyparis obtusa using 1% driselase or 0.25% pectolyase Y-23 in combination with 1% cellulase RS in 0.6M mannitol solution. Cell division and colony formation were induced efficiently in liquid Murashige and Skoog’s (MS) medium containing 0.6M mannitol and 10 to 30 μM 2,4-dichlorophenoxyacetic acid or 1 μM of naphthaleneacegic acid at the cell density of 1 to 2×103 ml. Continued callus proliferations was observed by transferring tissue to fresh medium of the same composition as the induction medium without mannitol. Campbell and Durzan’s medium and ammonium nitrate-free MS medium were less effective than MS medium. High concentration of benzyladenine (1 or 10 μM) was inhibitory to cell division.  相似文献   
2.
The stability of Watson–Crick paired RNA/DNA hybrids is important for designing optimal oligonucleotides for ASO (Antisense Oligonucleotide) and CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)–Cas9 techniques. Previous nearest-neighbour (NN) parameters for predicting hybrid stability in a 1 M NaCl solution, however, may not be applicable for predicting stability at salt concentrations closer to physiological condition (e.g. ∼100 mM Na+ or K+ in the presence or absence of Mg2+). Herein, we report measured thermodynamic parameters of 38 RNA/DNA hybrids at 100 mM NaCl and derive new NN parameters to predict duplex stability. Predicted ΔG°37 and Tm values based on the established NN parameters agreed well with the measured values with 2.9% and 1.1°C deviations, respectively. The new results can also be used to make precise predictions for duplexes formed in 100 mM KCl or 100 mM NaCl in the presence of 1 mM Mg2+, which can mimic an intracellular and extracellular salt condition, respectively. Comparisons of the predicted thermodynamic parameters with published data using ASO and CRISPR–Cas9 may allow designing shorter oligonucleotides for these techniques that will diminish the probability of non-specific binding and also improve the efficiency of target gene regulation.  相似文献   
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Dimethyl sulfoxide (DMSO) is currently used as an alternative treatment for various inflammatory conditions as well as for cancer. Despite its widespread use, there is a paucity of data regarding its safety and efficacy as well as its mechanism of action in human cells. Herein, we demonstrate that DMSO has ex-vivo anti-inflammatory activity using Escherichia coli- (E. coli) and herpes simplex virus-1 (HSV-1)-stimulated whole human blood. Specifically, we found that between 0.5%– 2%, DMSO significantly suppressed the expression of many pro-inflammatory cytokines/chemokines and prostaglandin E2 (PGE2). However, a significant reduction in monocyte viability was also observed at 2% DMSO, suggesting a narrow window of efficacy. Anti-inflammatory concentrations of DMSO suppressed E. coli-induced ERK1/2, p38, JNK and Akt phosphorylation, suggesting DMSO acts on these signaling pathways to suppress inflammatory cytokine/chemokine production. Although DMSO induces the differentiation of B16/F10 melanoma cells in vitro, topical administration of DMSO to mice subcutaneously implanted with B16 melanoma cells was ineffective at reducing tumor growth, DMSO was also found to block mouse macrophages from polarizing to either an M1- or an M2-phenotype, which may contribute to its inability to slow tumor growth. Topical administration of DMSO, however, significantly mitigated K/BxN serum-induced arthritis in mice, and this was associated with reduced levels of pro-inflammatory cytokines in the joints and white blood cell levels in the blood. Thus, while we cannot confirm the efficacy of DMSO as an anti-cancer agent, the use of DMSO in arthritis warrants further investigation to ascertain its therapeutic potential.  相似文献   
5.
Hypertrophy of adipocytes in obese adipose tissues causes metabolic abnormality by adipocytokine dysregulation, which promotes type 2 diabetes mellitus, hypertension, and dyslipidemia. We investigated the effects of wasabi (Wasabia japonica Matsum) leaf extracts on metabolic abnormalities in SHRSP.Z-Leprfa/IzmDmcr rats (SHRSP/ZF), which are a model of metabolic syndrome. Male SHRSP/ZF rats aged 7 weeks were divided into two groups: control and wasabi leaf extract (WLE) groups, which received water or oral treatment with 4 g/kg/day WLE for 6 weeks. WLE improved the body weight gain and high blood pressure in SHRSP/ZF rats, and the plasma triglyceride levels were significantly lower in the WLE group. Adipocyte hypertrophy was markedly prevented in adipose tissue. The expression of PPARγ and subsequent downstream genes was suppressed in the WLE group adipose tissues. Our data suggest that WLE inhibits adipose hypertrophy by suppressing PPARγ expression in adipose tissue and stimulating the AMPK activity by increased adiponectin.  相似文献   
6.
Personalized medicine allows the selection of treatments best suited to an individual patient and disease phenotype. To implement personalized medicine, effective tests predictive of response to treatment or susceptibility to adverse events are needed, and to develop a personalized medicine test, both high quality samples and reliable data are required. We review key features of state-of-the-art proteomic profiling and introduce further analytic developments to build a proteomic toolkit for use in personalized medicine approaches. The combination of novel analytical approaches in proteomic data generation, alignment and comparison permit translation of identified biomarkers into practical assays. We further propose an expanded statistical analysis to understand the sources of variability between individuals in terms of both protein expression and clinical variables and utilize this understanding in a predictive test.  相似文献   
7.
The synergistic effects of 6-alk(en)ylsalcylic acids, also known as anacardic acids, in combination with methicillin against Staphylococcus aureus ATCC 33591 (MRSA) was investigated. The double bond in C15-anacardic acids is not essential in eliciting the antibacterial activity but is associated with increasing the activity. The synergistic effects decreased with increasing the number of double bonds in the alkyl chain. On the other hand, the antibacterial activity of anacardic acids possessing different alkyl chain lengths against the same MRSA strain was found to be a parabolic function of their lipophilicity and maximized with the alkyl chain length of C10 and C12. Notably, the synergistic effects were noted to increase with increasing the alkyl chain length.  相似文献   
8.
Membrane glycoproteins of neural cells play crucial roles in axon guidance, synaptogenesis, and neuronal transmission. We have here characterized membrane glycoproteins containing terminal alpha-mannose residues in rat brain membranes. Affinity purification using Galanthus nivalis agglutinin, that is highly specific for terminal alpha-mannose residues, revealed a 50-kDa protein as well as 80-kDa SHPS-1 and 45-kDa beta2 subunit of Na,K-ATPase in rat brain membranes. Combination of N-terminal peptide sequencing and mass spectrometry indicated that the 50-kDa protein was rat nucleotide pyrophosphatase-5 (NPP-5). In contrast to other NPPs, NPP-5 was a type-I transmembrane protein. Northern blot analysis showed that NPP-5 was highly expressed in brain, but also expressed in other peripheral tissues. However, we could not detect either the NPP activity or the lysophospholipase D activity in the immunoprecipitates with antibodies to NPP-5 from rat brain membranes. These data, therefore, suggest that NPP-5 is a neural oligomannosidic glycoprotein that may participate in neural cell communications.  相似文献   
9.
Summary A factor with a molecular weight of less than 1 kDa in the mucosa of the bovine small intestine (low molecular weight factor or LMW factor) stimulated DNA synthesis in rat hepatocytes in primary culture. This factor only showed its activity when it was added with a larger factor with a molecular weight of 30 kDa that was also found in the same tissue (high molecular weight factor or HMW factor). The LMW factor probably acts to enhance the action of a hepatotrophic growth factor, since EGF and HGF can substitute for the HMW factor. The action of the LMW factor was not due to the actions of low molecular weight substances such as norepinephrine, estradiol, triiodothyronine, and putrescine, which enhance the action of EGF or HGF, since substantial amounts of these substances were not found in the extract. When intraperitoneally administered into rats, after two-thirds hepatectomy, the LMW factor enhanced hepatocyte proliferation without the administration of the HMW factor. In the regenerating liver, a hepatotrophic growth factor(s), which acts synergistically with the LMW factor, might be properly provided, but the supply of the LMW factor might be below the level that maximally stimulates hepatocyte proliferation.  相似文献   
10.
Light climates strongly influence plant architecture and mass allocation. Using the metamer concept, we quantitatively described branching architecture and growth of Chenopodium album plants grown solitarily or in a dense stand. Metamer is a unit of plant construction that is composed of an internode and the upper node with a leaf and a subtended axillary bud. The number of metamers on the main-axis stem increased with plant growth, but did not differ between solitary and dense-stand plants. Solitary plants had shorter thicker internodes with branches larger in size and number than the plant in the dense stand. Leaf area on the main stem was not different. Larger leaf area in solitary plants was due to a larger number of leaves on branches. Leaf mass per area (LMA) was higher in solitary plants. It did not significantly differ between the main axis and branches in solitary plants, whereas in the dense stand it was smaller on branches. Dry mass was allocated most to leaves in solitary plants and to stems in the dense stand in vegetative growth. Reproductive allocation was not significantly different. Branch/main stem mass ratio was higher in solitary than dense-stand plants, and leaf/stem mass ratio higher in branches than in the main axis. Nitrogen use efficiency (NUE) (dry mass growth per unit N uptake) was higher and light use efficiency (LUE) (dry mass growth per unit light interception) was lower in the plant grown solitarily than in the dense stand.  相似文献   
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