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31.
Transforming growth factor beta (TGF-beta) can promote late stage tumor progression in a number of model systems. In the present study, we have examined whether expression of a truncated soluble extracellular domain of TGF-beta type III receptor (sRIII) in human breast cancer MDA-MB-231 cells can antagonize the tumor-promoting activity of TGF-beta by sequestering active TGF-beta isoforms that are produced by the cancer cells. The secretion of sRIII reduced the amount of active TGF-beta1 and TGF-beta2 in the conditioned medium. This led to a significant reduction of the growth-inhibitory activity of the medium conditioned by sRIII-expressing cells on the growth of mink lung epithelial CCL64 cells in comparison with the medium conditioned by the control cells. The tumor incidence and growth rate of all of the three sRIII-expressing clones studied were significantly lower than those of the control cells in athymic nude mice. Four of five control cell-inoculated mice showed spontaneous metastasis in the lung, whereas none of the sRIII-expressing cell-inoculated mice had any lung metastasis. Thus, our results suggest that the sRIII may be used to antagonize the tumor-promoting activity of TGF-beta.  相似文献   
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33.
Peripheral arterial occlusive disease: P-31 MR spectroscopy of calf muscle   总被引:3,自引:0,他引:3  
Williams  DM; Fencil  L; Chenevert  TL 《Radiology》1990,175(2):381-385
The effect of a graded exercise protocol on phosphorus-31 magnetic resonance (MR) spectroscopy of calf skeletal muscle in nine healthy (control) subjects and 16 patients with symptomatic peripheral arterial occlusive disease (PAOD) was assessed. Ankle-brachial pressure indexes were obtained in all 16 patients, and 10 patients underwent peripheral arteriography. Temporal profiles of pH and the inorganic phosphorus (Pi) index were calculated from the spectra. A Pi-index recovery rate constant was calculated for each subject. Arteriograms were graded by calculating the runoff resistance in the limb of interest. The pH profiles during exercise did not differ significantly between the PAOD patients and control subjects. The Pi-index recovery rate constant in the PAOD patients was significantly (P less than .01) smaller than in the control subjects. There was no significant correlation between recovery rate and the ankle-brachial pressure indexes, but there was a strong negative correlation between recovery rates and angiographic resistance grades, with smaller recovery rate constants in patients with increased arterial resistance. It is concluded that P-31 MR spectroscopy shows promise as a direct measure of tissue perfusion.  相似文献   
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35.
BACKGROUND: The potential use of solvent/detergent-treated plasma (S/D plasma) in transfusion practice raises concerns about the cytolytic effects that any residual solvent and detergent in the virally inactivated blood component might have on units of red cells in vitro, if the two components are mixed during preparation. STUDY DESIGN AND METHODS: S/D plasma was mixed with variously processed units of stored red cells, in vitro, to evaluate the effect the residual solvent and detergent would have on cell membrane integrity. A paired protocol design was used in which half-units of red cells were exposed to S/D plasma (test), and the matched half-units were exposed to either the supernatant additive solution from the original red cell unit or standard fresh-frozen plasma (FFP) (control). After incubation for up to 5 days, the units were evaluated for evidence of hemolysis or changes in other red cell storage assays. RESULTS: This study showed that, for fresh additive solution red cells (AS-1), the 5-day storage plasma hemoglobin levels were comparable in the red cells exposed to S/D plasma (21 mg/dL) and in the paired half-units stored in the original AS-1 supernatant (31 mg/dL) (p > 0.05). Similar findings were recorded for stored AS-1 red cells (S/D plasma; 111 mg/dL vs. AS-1 supernatant, 147 mg/dL; p > 0.05); stored CPDA-1 red cells (S/D plasma, 133 mg/dL vs. FFP, 103 mg/dL; p > 0.05); frozen red cells (S/D plasma, 28 mg/dL vs. FFP, 18 mg/dL; p > 0.017); and stored irradiated AS-1 red cells (S/D plasma, 608 mg/dL vs. AS-1 supernatant, 726 mg/dL; p > 0.05). Comparable results were found for other assays, including levels of plasma potassium, osmotic fragility, and red cell antigen titer. CONCLUSION: These data show that S/D plasma does not induce red cell lysis even after 5 days of in vitro storage. These results are consistent with previous findings by this laboratory that platelets are not harmed by storage in S/D plasma. Red cells resuspended in S/D plasma and stored for up to 5 days maintain in vitro storage characteristics that are acceptable for the use of the cells in clinical transfusion practice.  相似文献   
36.
目的:观察褪黑素对自身免疫性肝炎大鼠模型外周血淋巴细胞亚群的影响方法:实验于2004-10/2006-10在解放军第一二三医院南京军区肝病中心实验室完成。①实验材料:Wistar大鼠,雄性,3月龄,体质量(230±20)g,购自上海斯莱克实验动物有限责任公司。褪黑素:美国Sigma公司产品,临用前以无水乙醇溶解,再加生理盐水配制,使乙醇浓度为0.1%,置4℃冰箱保存备用。②实验方法:采用弗氏完全佐剂加肝细胞特异性脂蛋白法制作大鼠自身免疫性肝炎模型。将建模成功大鼠随机分为模型对照组、褪黑素注射组及猪促肝细胞生长素注射组,每组20只。褪黑素注射组褪黑素2mg/kg腹腔注射,1次/d,猪促肝细胞生长素注射组2mg/kg猪促肝细胞生长素腹腔注射,1次/d,模型对照组与正常对照组均用含0.01%乙醇的生理盐水腹腔注射。③实验评估:60d后检测各组大鼠外周血淋巴细胞亚群浓度。结果:①CD4 细胞≤39.5只,均为褪黑素注射组动物,肝炎组织活动性指数≤8分。22只CD4 细胞>39.5%动物中,4只肝炎组织活动性指数≤8分,其中2只为褪黑素注射组动物,2只为模型对照组动物。18只肝炎组织活动性指数>8分,均为模型对照组动物。②18只CD4 细胞≤39.5%褪黑素注射组动物中,17只肝纤维化指数≤4分,1只肝纤维化指数4分;22只动物CD4 细胞>39.5%,2只肝纤维化指数≤4分,为模型对照组动物,20只肝纤维化指数>4分,褪黑素注射组2只,模型对照组18只。③CD4 细胞≤39.5%,肝组织血管病变均为1级,>39.5%时,2级以上血管病变为90.9%。18只CD4 细胞≤39.5%褪黑素注射动物血管病变为1级。22只CD4 细胞百分比>39.5%,2只血管病变为1级,为模型对照动物,17只血管病变为2级,褪黑素注射组2只,模型对照组15只。3只血管病变为3级,为模型对照动物。④CD4 细胞≤39.5%时,83.3%血管内皮细胞生长因子表达呈弱阳性,CD4 细胞>39.5%时,81.8%血管内皮细胞生长因子表达呈强阳性,提示CD4 细胞与血管内皮细胞生长因子表达有关。⑤模型对照组外周血CD4 细胞数和CD4 /CD8 比值均明显高于其他组(P<0.05),CD8 细胞与其他组无明显差异(P>0.05)。褪黑素注射动物与猪促肝细胞生长素注射动物相比,无明显差异(P>0.05)。结论:褪黑素对自身免疫性肝炎模型大鼠外周血CD4 细胞有较强的抑制作用。  相似文献   
37.

Background and purpose:

α- and β-amyrin are pentacyclic triterpenes found in plants and are known to exhibit pronounced anti-inflammatory effects. Here, we evaluated the effects of a 1:1 mixture of α- and β-amyrin (α,β-amyrin) on an experimental model of colitis in mice.

Experimental approach:

Colitis was induced in Swiss male mice by trinitrobenzene sulphonic acid (TNBS) and followed up to 72 h; animals were treated systemically with α,β-amyrin, dexamethasone or vehicle. Macro- and microscopic damage, myeloperoxidase activity and cytokine levels were assessed in colons. Histological sections were immunostained for cyclooxygenase-2 (COX-2), vascular endothelial growth factor, phospho-p65 nuclear factor-κB (NF-κB) and phospho-cyclic AMP response element-binding protein (CREB)

Key results:

TNBS-induced colitis was associated with tissue damage, neutrophil infiltration and time-dependent increase of inflammatory mediators. Treatment with α,β-amyrin (3 mg·kg−1, i.p.) or dexamethasone (1 mg·kg−1, s.c.) consistently improved tissue damage scores and abolished polymorphonuclear cell infiltration. α,β-Amyrin, like dexamethasone, significantly diminished interleukin (IL)-1β levels and partially restored IL-10 levels in colon tissues 72 h after colitis induction, but only α,β-amyrin reduced vascular endothelial growth factor expression by immunohistochemistry. The colonic expression of COX-2 at 24 h and that of phospho-NF-κB and phospho-CREB (peaking at 6 h) after colitis induction were consistently inhibited by both α,β-amyrin and dexamethasone.

Conclusions and implications:

Systemic administration of α,β-amyrin exerted a marked and rapid inhibition of TNBS-induced colitis, related to the local suppression of inflammatory cytokines and COX-2 levels, possibly via inhibition of NF-κB and CREB-signalling pathways. Taken together, our data suggest a potential use of α,β-amyrin to control inflammatory responses in bowel disease.  相似文献   
38.
Composite tissue allotransplantation holds great promise for upper extremity reconstruction but is limited by donor part availability. Cryopreservation may increase the availability of donor parts and even reduce antigenicity. The purpose of the study was to evaluate the viability of cryopreserved composite tissues and to demonstrate the feasibility of microvascular isotransplantation of cryopreserved composite flaps. Twenty epigastric flaps were harvested from Lewis rats. Ten flaps were analyzed fresh. Ten flaps were perfused with dimethyl sulfoxide (DMSO)/trehelose cryoprotectant agent (CPA), frozen by controlled cooling to −140°C, and stored for 2 weeks. Flaps were evaluated by factor VIII endothelial staining and MTT tetrazolium salt assay. For the in vivo phase, 30 flaps were harvested. Ten were transplanted fresh to isogenetic recipient animals, ten were perfused with CPA and transplanted, and ten were cryopreserved for 2 weeks, thawed, and transplanted. All cryopreserved samples displayed intact vascular endothelia on factor VIII staining. On MTT analysis, the epithelial viability index for the cryopreserved samples was not significantly different from fresh controls (p = 0.12). All freshly transplanted flaps (10/10) were viable at 60 days. Nine of ten flaps in the perfused/transplanted group were viable at 60 days. Survival of cryopreserved/transplanted flaps ranged from 5 to 60 days. The skin and vascular endothelial components of composite tissue flaps appear to retain their viability after cryopreservation. The in vivo studies demonstrate that the long-term survival of cryopreserved composite tissue transplants is feasible and support an indirect injury, rather than direct injury from freezing or cryoprotectant agents, as the mechanism of flap loss. Presented at the Annual Meeting of the American Association for Hand Surgery, Rio Grande, Puerto Rico, January, 2007.  相似文献   
39.
Smoking is a high-risk behavior that affects the health and economic welfare of society. Thus, it is important to quantify the economic burden smoking places on social institutions in the United States.
OBJECTIVE: The purpose of this review paper is to analyze smoking cost studies and to provide estimates that represent the economic costs of smoking from different perspectives of society, and as a whole.
METHODS: Current Contents (1996–), Health Star (1970–), and Medline (1966–) databases were searched through the use of pertinent subject headings and key words: tobacco use, smoking, cost, and economics. The internet was utilized to identify potential sources of epidemiological and cost information on smoking. Recent cost-of-illness studies using different methodologies: human capital, incidence, and prevalence were chosen for review based on their relevance.
RESULTS: Preliminary results indicate that the published cost studies available underestimate the "true" costs of smoking. The most current articles approximate annual direct medical costs to health care payers of $50 billion (1993); inflating to 1997 equals $59 billion or $1,200 per smoker. Although the latest cost studies do not attempt to estimate indirect costs, past studies have found indirect costs to be 1.5–2 times the direct costs. Therefore, using direct and indirect costs we estimate total smoking costs to be $150 billion (1993); inflating to 1997 equals $176 billion or $3,500 per smoker.
CONCLUSION: Quantifying the cost of smoking is a difficult task due to tobacco use infiltrating many aspects of life and the dependency of cost on perspective. Cost-of-illness studies provide cost estimation data which can be useful in aiding decision-makers who are allocating health care resources.  相似文献   
40.
Kenney  RT; Malech  HL; Epstein  ND; Roberts  RL; Leto  TL 《Blood》1993,82(12):3739-3744
The genetic defect in the p67phox-deficient form of chronic granulomatous disease (CGD) follows an autosomal recessive pattern of inheritance. When genomic DNA from normal individuals is digested with HindIII and probed with p67phox cDNA an allelic restriction fragment length polymorphism (RFLP) of 4.0 kb or 2.3 kb is detected. We cloned and characterized the p67phox gene using the cDNA and sequenced the exon/intron boundaries, mapping 16 exons on the 40-kb gene. The polymorphic region was then sequenced to identify the inheritance pattern of amniocentesis-derived fetal cells by genomic amplification. The proband, a 9-year-old female patient with p67phox-deficient CGD, and her phenotypically normal mother are homozygous for the RFLP marker, whereas the father and two brothers are heterozygous. The fetus was shown to be heterozygous as well, showing it had inherited at least one normal p67phox gene from the father and that it was predicted to have a normal phenotype. Cord blood samples at birth showed normal oxidative function. Amplification allows rapid detection of the inheritance pattern for fetal diagnosis in informative families. We report the genomic structure of p67phox and an amplification-based method for detection of the marker on chromosome 1q25, used here for prenatal diagnosis of CGD.  相似文献   
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