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101.
This study aimed to evaluate the ability of the health food supplement Cordyceps sinensis (CS) to ameliorate suppressive effects of chemotherapy on bone marrow function as a model for cancer treatment. Mice were treated with Taxol (17 mg/kg body wt) one day before oral administration of a hot-water extract of CS (50 mg/kg daily) that was given daily for 3 weeks. White blood cell counts in peripheral blood of mice receiving Taxol were at 50% of normal levels on day 28 but had recovered completely in mice treated with CS. In vitro assays showed that CS enhanced the colony-forming ability of both granulocyte macrophage colony forming unit (GM-CFU) and osteogenic cells from bone marrow preparations and promoted the differentiation of bone marrow mesenchymal stromal cells into adipocytes, alkaline phosphatase-positive osteoblasts, and bone tissue. This result could be attributed to enhanced expression of Cbfa1 (core binding factor a) and BMP-2 (bone morphogenetic protein) with concurrent suppression of ODF (osteoclast differentiation factor/RANK [receptor activator of NF-kappaB]) ligand. In summary, CS enhances recovery of mice from leukopenia caused by Taxol treatment. It appears to do so by protecting both hematopoietic progenitor cells directly and the bone marrow stem cell niche through its effects on osteoblast differentiation.  相似文献   
102.
转基因在玉米中的遗传分离与整合特性的研究   总被引:23,自引:0,他引:23  
王守才  丁群星 《遗传学报》1999,26(3):254-261
用PCR和DNA分子杂交方法研究了转基因Bt在3种不同方法获得的8个转化体后代中的遗传分离、整合性质及其稳定性,结果表明:(1)转基因在大多数转化体后中呈简单的孟德尔遗传;在R1至R2代,部分家系中转化体比例偏低,有的发生转基因丢失,但到R3代以后均趋于正常的孟德尔遗传方式,在群体中固定下来;(2)转基因在不同转化体中的整合类型有一定差异,但整合的位点和拷贝数都较少,且多呈串联或紧密连锁的整合;(  相似文献   
103.
Orally bioavailable, dual inhibitors of TIE-2/VEGF-R2 were identified by elaborating the C3/N13 SAR around a fused pyrrolodihydroindazolocarbazole scaffold. Analogs bearing a C3-thiophencarbonyl group were evaluated in enzymatic and cellular biochemical assays; two orally bioavailable analogs were further profiled in functional assays and found to inhibit microvessel growth in rat aortic explant cultures and inhibit Ang-1-stimulated chemotaxis of HUVECs.  相似文献   
104.
The switching on-and-off of I-kappaB kinase (IKK) and NF-kappaB occurs rapidly after signaling. How activated IKK becomes down-regulated is not well understood. Here we show that following tumor necrosis factor-alpha stimulation, protein phosphatase 2A (PP2A) association with IKK is increased. A heptad repeat in IKKgamma, helix 2 (HLX2), mediates PP2A recruitment. Two other heptad repeats downstream of HLX2, termed coiled-coil region 2 (CCR2) and leucine zipper (LZ), bind HLX2 and negatively regulate HLX2 interaction with PP2A. HTLV-1 transactivator Tax also binds HLX2, and this interaction is enhanced by CCR2 but reduced by LZ. In the presence of Tax, PP2A-IKKgamma binding is greatly strengthened. Interestingly, peptides spanning CCR2 and/or LZ disrupt IKKgamma-Tax and IKKgamma-PP2A interactions and potently inhibit NF-kappaB activation by Tax and tumor necrosis factor-alpha. We propose that when IKK is resting, HLX2, CCR2, and LZ form a helical bundle in which HLX2 is sequestered. The HLX2-CCR2-LZ bundle becomes unfolded by signal-induced modifications of IKKgamma or after Tax binding. In this conformation, IKK becomes activated. IKKgamma then recruits PP2A via the exposed HLX2 domain for rapid down-regulation of IKK. Tax-PP2A interaction, however, renders PP2A inactive, thus maintaining Tax-PP2A-IKK in an active state. Finally, CCR2 and LZ possibly inhibit IKK activation by stabilizing the HLX2-CCR2-LZ bundle.  相似文献   
105.
Human lemur (Lmr) kinases are predicted to be Tyr kinases based on sequences and are related to neurotrophin receptor Trk kinases. This study used homogeneous recombinant KPI-2 (Lmr2, LMTK2, Cprk, brain-enriched protein kinase) kinase domain and a library of 1,154 peptides on a microarray to analyze substrate specificity. We found that KPI-2 is strictly a Ser/Thr kinase that reacts with Ser either preceded by or followed by Pro residues but unlike other Pro-directed kinases does not strictly require an adjacent Pro residue. The most reactive peptide in the library corresponds to Ser-737 of cystic fibrosis transmembrane conductance regulator, and the recombinant R domain of cystic fibrosis transmembrane conductance regulator was a preferred substrate. Furthermore the KPI-2 kinase phosphorylated peptides corresponding to the single site in phosphorylase and purified phosphorylase b, making this only the second known phosphorylase b kinase. Phosphorylase was used as a specific substrate to show that KPI-2 is inhibited in living cells by addition of nerve growth factor or serum. The results demonstrate the utility of the peptide library to probe specificity and discover kinase substrates and offer a specific assay that reveals hormonal regulation of the activity of this unusual transmembrane kinase.  相似文献   
106.

Objective

Progranulin and C1q/TNF-related protein-3 (CTRP3) were recently discovered as novel adipokines which may link obesity with altered regulation of glucose metabolism, chronic inflammation and insulin resistance.

Research Design and Methods

We examined circulating progranulin and CTRP3 concentrations in 127 subjects with (n = 44) or without metabolic syndrome (n = 83). Furthermore, we evaluated the relationship of progranulin and CTRP3 levels with inflammatory markers and cardiometabolic risk factors, including high-sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), estimated glomerular filtration rate (eGFR), and adiponectin serum concentrations, as well as carotid intima-media thickness (CIMT).

Results

Circulating progranulin levels are significantly related with inflammatory markers, hsCRP (r = 0.30, P = 0.001) and IL-6 (r = 0.30, P = 0.001), whereas CTRP3 concentrations exhibit a significant association with cardiometabolic risk factors, including waist circumference (r = −0.21), diastolic blood pressure (r = −0.21), fasting glucose (r = −0.20), triglyceride (r = −0.34), total cholesterol (r = −0.25), eGFR (r = 0.39) and adiponectin (r = 0.26) levels. Serum progranulin concentrations were higher in patients with metabolic syndrome than those of the control group (199.55 [179.33, 215.53] vs. 185.10 [160.30, 204.90], P = 0.051) and the number of metabolic syndrome components had a significant positive correlation with progranulin levels (r = 0.227, P = 0.010). In multiple regression analysis, IL-6 and triglyceride levels were significant predictors of serum progranulin levels (R 2 = 0.251). Furthermore, serum progranulin level was an independent predictor for increased CIMT in subjects without metabolic syndrome after adjusting for other cardiovascular risk factors (R 2 = 0.365).

Conclusions

Serum progranulin levels are significantly associated with systemic inflammatory markers and were an independent predictor for atherosclerosis in subjects without metabolic syndrome.

Trial Registration

ClinicalTrials.gov NCT01668888  相似文献   
107.
Yang  Z. T.  Lu  D. X.  Hong  E.-K.  Zhang  B. Y.  Jiang  M. C.  Yang  Y. J.  Zhang  D. J. 《Molecular Biology》2020,54(6):911-918
Molecular Biology - Brassica campestris L. is the important oil-bearing crop in China. Rapeseed cake is the main byproduct of rapeseed oil extraction. As the main active ingredient in rapeseed...  相似文献   
108.
适宜的麻醉深度是保证患者的生命安全和创造良好手术条件的关键。脑电双频指数(bispectralindex,BIS)是用于监测镇静程度的一种新方法,自从临床应用以来它已得到多方面关注和研究,本文就其概念、原理及临床应用等方面进行综述。  相似文献   
109.
Various physiological and psychological functions are influenced by circadian typology (CT), which was reported to be related to resilience. However, few studies have assessed the effects of CT in relation to resilience. The aim of the present study was to assess the influence of CT on sleep-related symptoms, physical fatigue and psychological well-being in relation to resilience. The present study included a total of 1794 healthy hospital employees, and they completed the Morningness–Eveningness Questionnaire, Connor–Davidson Resilience Scale, Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, Fatigue Severity Scale, Hospital Anxiety and Depression Scale and World Health Organization Quality of Life Scale Abbreviated Version. Subjects with evening type showed lower sleep quality, more daytime sleepiness and physical fatigue than neither types and morning types. Additionally, evening types were more depressed and anxious and reported a poorer quality of life. CT was found to be a significant predictor of sleep quality, but CT was minimally associated with physical fatigue and psychological well-being in the regression analysis. Instead, resilience was substantially related to all of the variables measured. In conclusion, CT independently predicts sleep quality, but the effects of CT on physical fatigue and psychological well-being are negligible compared to those of resilience.  相似文献   
110.
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