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31.
Obesity and its associated metabolic syndrome (MetS) are recognized risk factors for breast cancer. The molecular basis for this association remains largely unknown. Adipokines, in particular leptin and adiponectin, are thought to form part of the mechanism linking obesity with cancer through their altered expression/production either systemically (endocrine pathway) or locally (paracrine/autocrine pathway). Using quantitative PCR, mRNA expression of adiponectin (AdipoQ) and leptin (Ob) in mammary adipose tissue (MAT), intratumoral leptin and associated ligand receptors (ObR, AdipoR1, and AdipoR2) was examined in 77 patients with complete anthropomorphic and serological data. Expression of Ob in MAT, and ObR in matched tumor tissue was significantly higher in patients with MetS compared to obese only or normal weight cancer patients (P < 0.005). There was no difference in intratumoral leptin adiponectin or its ligand receptors in the same groups. Individual features of MetS correlated with Ob and ObR expression, but not obesity markers (BMI, waist circumference). mRNA expression of leptin (Ob) and ObR, in adipose tissue and matched tumor samples, respectively, appear to be associated with obesity status in breast cancer. Increasing insulin resistance is a predominant feature of this higher Ob/ObR expression observed. These novel data indicate that the MetS may be an amenable risk factor for breast cancer. © 2011 Wiley‐Liss, Inc.  相似文献   
32.

Background  

Thromboxane synthase (TXS) metabolises prostaglandin H2 into thromboxanes, which are biologically active on cancer cells. TXS over-expression has been reported in a range of cancers, and associated with a poor prognosis. TXS inhibition induces cell death in-vitro, providing a rationale for therapeutic intervention. We aimed to determine the expression profile of TXS in NSCLC and if it is prognostic and/or a survival factor in the disease.  相似文献   
33.
血管细胞粘附分子调控造血的研究进展   总被引:1,自引:1,他引:1  
本文简述了血管细胞粘附分子 (Vascularcelladhesionmolecule 1,VCAM 1)的结构和生物学功能 ,总结了VCAM 1在恶性血液病骨髓基质中的表达和意义 ,探讨了VCAM 1在造血干细胞动员和归巢中的作用 ,指出VCAM 1作用机制的深入研究将对恶性血液病的治疗提供更为有效的方法。  相似文献   
34.
Respond on comments on Lieberman's article: Cyclosiloxanes Produce Fatal Liver and Lung Damage in Mice. Environ Health Perspect 107:161-165  相似文献   
35.
4-烷硫基-4-脱氧-4′-去甲表鬼臼毒素的合成和抗肿瘤活性   总被引:6,自引:0,他引:6  
对4’-去甲表鬼臼毒素的C4位进行化学修饰,合成和筛选了10个4-烷硫基-4-脱氧-4’-去甲表鬼臼毒素衍生物以进一步研究C4位不同的原子和取代基与活性之间的关系及寻找结构简单、活性更强的抗肿瘤新药。4’-去甲表鬼臼毒素与硫醇在三氟化硼·乙醚或三氟乙酸存在下生成相应的硫醚,也可用硫醇与4β-溴-4-脱氧-4’-去甲表鬼臼毒素反应生成相应的硫醚。在体外筛选中,化合物10和12抑制L1210白血病细胞的活性与依托泊甙相当或更强,化合物9,10,12和15抑制KB细胞的活性与依托泊甙相当或更强。  相似文献   
36.
1. The possibility that altered synthesis of vascular nitric oxide (NO) plays a role in the development of corticotropin-induced hypertension in sheep was examined by determining the effect of concomitant infusion of L-arginine, a precursor of NO, on the development of the hypertension. 2. Corticotropin (5 μg/kg per h) infused over 2 days increased mean arterial pressure (MAP) from 83 ± 4 to 99 ± 4 mmHg in five conscious sheep. Concomitant infusion of L-arginine (60 mg/kg per h) did not alter this response; infusion of L-arginine alone had no effect on blood pressure. 3. The dose of L-arginine (60 mg/kg per h) used blocked the rise in MAP (+16 mmHg) in response to a 5 h infusion of N-nitro-L-arginine (1 mg/kg per h). 4. These findings suggest that disruption of NO synthesis does not play a role in the development of corticotropin hypertension in sheep.  相似文献   
37.
We report for the first time the development of Nelson's syndrome in a patient who had previously undergone unsuccessful pituitary microadenomectomy and subsequently bilateral adrenalectomy. The removal of a 3-mm portion of a microadenoma did not protect against the development of Nelson's syndrome within 3 years which was closely related to pregnancy, a previously noted association. This report suggests that the development of Nelson's syndrome depends not on the size of the initial pituitary tumour but rather on its individual potential for proliferating once free of the inhibitory effects of glucocorticoid excess.  相似文献   
38.
锌酞菁脂质体光动力作用引起小鼠肿瘤的细胞程序性死亡   总被引:4,自引:1,他引:3  
电镜观察了锌酞菁脂质体光动力作用引起小鼠MS-2纤维肉瘤的形态学变化。发现其作用很强,并对肿瘤细胞有明显的直接影响。肿瘤细胞的结构表现出明显的程序性细胞死亡(apoptosis,programmedceldeath)的特点:胞核染色质凝聚边集、核固缩、核破裂、染色质凝块流失、胞质内吞噬现象、胞膜表面肿胀粗钝的胞突形成、细胞碎裂等。加深了对锌酞菁脂质体光敏作用机理的认识,但其详细的发生机制和调节途径有待阐明。  相似文献   
39.
40.
Sham  RL; Packman  CH; Abboud  CN; Lichtman  MA 《Blood》1991,77(2):363-370
Maturation of human myeloid cells is associated with quantitative and qualitative changes in protein kinase C (PKC) and increases in N-formyl- L-methionyl-L-leucyl-L-phenylalanine (FMLP) receptors, actin, and actin regulatory proteins. We have studied the actin responses and cell shape changes caused by FMLP and its second messenger pathways in HL60 cells undergoing neutrophilic maturation. In uninduced cells, the PKC activators 12-O-tetradecanoyl phorbol-13-acetate (TPA), bryostatin, and 1-oleyl-2-acetylglycerol (OAG) resulted in 15% to 30% decreases in F- actin, whereas FMLP had no effect. Ionomycin had no effect on actin but did cause a 10-fold increase in intracellular calcium. Cells grown for 24 hours in 1% dimethyl sulfoxide (DMSO) acquired the ability to polymerize actin in response to FMLP and ionomycin. TPA continued to cause a decrease in F-actin at 24 hours, but caused an increase in F- actin at 48 to 72 hours of maturation. The PKC inhibitor 1-5- isoquinolinesulfonyl 2-methylpiperazine (H7) partially blocked the F- actin increase caused by TPA in induced cells, but had no effect on the decrease in F-actin caused by TPA in uninduced cells or the increase in F-actin seen in FMLP-treated neutrophils. F-actin rich pseudopods developed following TPA or FMLP stimulation of induced HL60 cells; in uninduced cells neither agent caused pseudopod formation but TPA caused a dramatic loss of surface ruffles. The ability of FMLP and ionomycin to elicit a neutrophil-like actin response in HL60 cells within 24 hours after DMSO treatment shows that the actin regulatory mechanism is mature by that time. The inability of ionomycin to increase F-actin in uninduced cells supports the view that calcium increases alone are insufficient for actin polymerization. The longer maturation time required for HL60 cells to develop an actin polymerization response to TPA compared with FMLP, coupled with the inability of H7 to block the FMLP-mediated F-actin increase in neutrophils, suggests that the F- actin increase caused by FMLP is not mediated solely by PKC. Lastly, the TPA-induced F-actin decrease and shape changes in uninduced HL60 cells, and the longer time required for a "mature" response to TPA, may reflect immaturity in the PKC isoenzyme pattern rather than immaturity of the actin regulatory mechanism.  相似文献   
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