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51.

Background

Dozens of Traditional Chinese Medicine (TCM) formulas have been used for promotion of "blood production" for centuries, and we are interested in developing novel thrombopoietic medicines from these TCMs. Our previous studies have demonstrated the hematopoietic effects of DangGui BuXue Tong (DBT), a formula composed of Radix Angelicae Sinensis and Radix Astragali in animal and cellular models. As a step further to identify and characterize the active chemical components of DBT, we tested the hematopoietic and particularly, thrombopoietic effects of polysaccharide-enriched fractions from the root of Radix Angelicae Sinensis (APS) in this study.

Methods

A myelosuppression mouse model was treated with APS (10 mg/kg/day). Peripheral blood cells from APS, thrombopoietin and vehicle-treated samples were then counted at different time-points. Using the colony-forming unit (CFU) assays, we determined the effects of APS on the proliferation and differentiation of hematopoietic stem/progenitor cells and megakaryocytic lineages. Using a megakaryocytic cell line M-07e as model, we analyzed the cellular apoptosis progression with and without APS treatment by Annexin V, Mitochondrial Membrane Potential and Caspase 3 assays. Last, the anti-apoptotic effect of APS on cells treated with Ly294002, a Phosphatidylinositol 3-Kinse inhibitor (PI3K) was also tested.

Results

In animal models, APS significantly enhanced not only the recovery of platelets, other blood cells and their progenitor cells, but also the formation of Colony Forming Unit (CFU). In M-07e cells, we observed the anti-apoptotic effect of APS. Treatment by Ly294002 alone increased the percentage of cells undergoing apoptosis. However, addition of APS to Ly294002-treated cells significantly reduced the percentage of cells undergoing apoptosis.

Conclusions

APS promotes hematopoiesis and thrombopoiesis in the mouse model. This effect likely resulted from the anti-apoptosis activity of APS and is likely to involve the PI3K/AKT pathway.  相似文献   
52.
非小细胞肺癌伴神经内分泌分化的研究   总被引:2,自引:2,他引:2  
目的:研究非小细胞肺癌的类型、分化程度与神经内分渥分化间接的关系。方法:随机收集43例手术切除石蜡包埋的非小细胞肺癌的标本,采用7种神经内分泌抗体,用免疫组化LSAB法研究其神经内分泌分化。结果:阳性率为53.4%,其中鳞癌和腺癌的阳性率分别为:52.9%和58.3%;而2例大细胞癌皆阴性。结论:非小细胞肺癌的组织类型与神经内分泌表达的种类有一定关系;而组织学类型和癌细胞分化程度与神经内分泌分化的  相似文献   
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Background:

Monoamine reuptake inhibitors exhibit unique clinical profiles that reflect distinct engagement of the central nervous system (CNS) transporters.

Methods:

We used a translational strategy, including rodent pharmacokinetic/pharmacodynamic modeling and positron emission tomography (PET) imaging in humans, to establish the transporter profile of TD-9855, a novel norepinephrine and serotonin reuptake inhibitor.

Results:

TD-9855 was a potent inhibitor of norepinephrine (NE) and serotonin 5-HT uptake in vitro with an inhibitory selectivity of 4- to 10-fold for NE at human and rat transporters. TD-9855 engaged norepinephrine transporters (NET) and serotonin transporters (SERT) in rat spinal cord, with a plasma EC50 of 11.7ng/mL and 50.8ng/mL, respectively, consistent with modest selectivity for NET in vivo.Accounting for species differences in protein binding, the projected human NET and SERT plasma EC50 values were 5.5ng/mL and 23.9ng/mL, respectively. A single-dose, open-label PET study (4–20mg TD-9855, oral) was conducted in eight healthy males using the radiotracers [11C]-3-amino-4- [2-[(di(methyl)amino)methyl]phenyl]sulfanylbenzonitrile for SERT and [11C]-(S,S)-methylreboxetine for NET. The long pharmacokinetic half-life (30–40h) of TD-9855 allowed for sequential assessment of SERT and NET occupancy in the same subject. The plasma EC50 for NET was estimated to be 1.21ng/mL, and at doses of greater than 4mg the projected steady-state NET occupancy is high (>75%). After a single oral dose of 20mg, SERT occupancy was 25 (±8)% at a plasma level of 6.35ng/mL.

Conclusions:

These data establish the CNS penetration and transporter profile of TD-9855 and inform the selection of potential doses for future clinical evaluation.  相似文献   
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Height, weight, and skinfold thickness were measured on 82 patients prior to muscle biopsy which was performed to determine their susceptibility to malignant hyperpyrexia. Percentage body fat was calculated from the skinfold measurements. Using AP photographs six coronal diameters of the left thigh. equally spaced between the lower border of the patella and the perineum, were measured on another group of 90 patients referred for biopsy. The subjects were then divided into those who were susceptible to malignant hyperpyrexia (MHS) and those who were normal and acted as controls. Each group was separated into males and females. There was no significant difference in age between the MHS and the control groups. There was no difference between MHS and controls in height or weight but the percentage body fat in the MHS males was significantly lower than in the controls (P<0.02). The upper three thigh diameters in the MHS females were significantly greater than in the control group (P<0.05). There appears to be a difference in the leanness/fatness relationship and in the development of the thigh in MHS subjects compared with controls, but these differences are subtle and appear to vary with sex.  相似文献   
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