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Estrogen exerts a primary regulatory role on a wide variety of physiological processes in different tissues and organs. Agonistic ad antagonistic compounds are widely used in human health and, therefore, a deep understanding of their mechanisms of action at the molecular level is mandatory. The effect of 17beta-estradiol and three antiestrogenic drugs, comprising two selective estrogen receptor modulator (SERM, 4-OH-tamoxifen, Raloxifene) and the pure antiestrogen ICI 182,780, on genome-wide gene expression levels was evaluated in breast carcinoma cell lines by DNA microarray analysis. Different clusters of genes, showing specific coregulation patterns, were found. First, several groups of genes displaying temporal-specific up- or down-regulation were characterized. Second, clusters of genes responding to different antiestrogenic drugs in either antagonstic or agonistic fashion, were found. Genes responding specifically to antiestrogens, but not to estrogen, were also identified. In addition, each individual compound exhibited a very specific gene regulation. Bioinformatic analysis was applied to the regulatory sequences of different groups of genes and confirmed that specific pathways and secondary responses are activated at each temporal point and in response to different compounds. Our results underline the complexity of genomic responses to estrogen in breast cancer cells and strongly suggest that the molecular characterization of estrogen agonists and antagonists used in human therapy should be carefully studied.  相似文献   
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Enhanced external counterpulsation (EECP) is a valuable therapeutic option for patients with coronary artery disease and refractory angina. Although the exact mechanisms by which this technique exerts favorable effects remain unclear, improvement in endothelial function is considered a potential mechanism contributing to the clinical benefit associated with EECP. We describe a young woman with severely symptomatic coronary endothelial dysfunction in the absence of obstructive coronary artery disease who experienced a dramatic and sustained reduction in symptoms in response to a standard 35-hour course of EECP.  相似文献   
95.
Since the mechanisms by which specific immunity destroys Her-2/neu carcinoma cells are highly undetermined, these were assessed in BALB/c mice vaccinated with plasmids encoding extracellular and transmembrane domains of the protein product (p185(neu)) of the rat Her-2/neu oncogene shot into the skin by gene gun. Vaccinated mice rejected a lethal challenge of TUBO carcinoma cells expressing p185(neu). Depletion of CD4 T cells during immunization abolished the protection, while depletion of CD8 cells during the effector phase halved it, and depletion of polymorphonuclear granulocytes abolished all protection. By contrast, Ig mu-chain gene KO mice, as well as Fcgamma receptor I/III, beta-2 microglobulin, CD1, monocyte chemoattractant protein 1 (MCP1), IFN-gamma, and perforin gene KO mice were protected. Only mice with both IFN-gamma and perforin gene KOs were not protected. Although immunization also cured all BALB/c mice bearing established TUBO carcinomas, it did not cure any of the perforin KO or perforin and IFN-gamma KO mice. Few mice were cured that had knockouts of the gene for Ig mu-chain, Fcgamma receptor I/III, IFN-gamma, or beta-2 microglobulin. Moreover, vaccination cured half of the CD1 and the majority of the MCP1 KO mice. The eradication of established p185(neu) carcinomas involves distinct mechanisms, each endowed with a different curative potential.  相似文献   
96.

Context

Erectile dysfunction (ED) is considered a vascular impairment that shares many risk factors with cardiovascular disease (CVD). A correlation between ED and CVD has been hypothesized, and ED has been proposed as an early marker of symptomatic CVD.

Objective

To analyze the relationship between ED and CVD, evaluating the pathophysiologic links between these conditions, and to identify which patients would benefit from cardiologic assessment when presenting with ED.

Evidence acquisition

A systematic literature review searching Medline, Embase, and Web of Science databases was performed. The search strategy included the terms erectile dysfunction, cardiovascular disease, coronary artery disease, risk factors, pathophysiology, atherosclerosis, low androgen levels, inflammation, screening, and phosphodiesterase type 5 inhibitors alone or in combination. We limited our search to studies published between January 2005 and May 2013.

Evidence synthesis

Several studies reported an association between ED and CVD. The link between these conditions might reside in the interaction between androgens, chronic inflammation, and cardiovascular risk factors that determines endothelial dysfunction and atherosclerosis, resulting in disorders of penile and coronary circulation. Because penile artery size is smaller compared with coronary arteries, the same level of endothelial dysfunction causes a more significant reduction of blood flow in erectile tissues compared with that in coronary circulation. Thus ED could be an indicator of systemic endothelial dysfunction. From a clinical standpoint, because ED may precede CVD, it can be used as an early marker to identify men at higher risk of CVD events. ED patients at high risk of CVD should undergo detailed cardiologic assessment and receive intensive treatment of risk factors.

Conclusions

ED and CVD should be regarded as two different manifestations of the same systemic disorder. ED usually precedes CVD onset, and it might be considered an early marker of symptomatic CVD.  相似文献   
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Genetic mutations of sporadic hemiplegic migraine (SHM) are mostly unknown. SHM pathophysiology relies on cortical spreading depression (CSD), which might be responsible for ischemic brain infarction. Cystic fibrosis (CF) is caused by a monogenic mutation of the chlorine transmembrane conductance regulator (CFTR), possibly altering brain excitability. We describe the case of a patient with CF, who had a migrainous stroke during an SHM attack. A 32-year-old Caucasian male was diagnosed with CF, with heterozygotic delta F508/unknown CFTR mutation. The patient experiences bouts of coughing sometimes triggering SHM attacks with visual phosphenes, aphasia, right-sided paresthesia, and hemiparesis. He had a 48-hour hemiparesis triggered by a bout of coughing with hemoptysis, loss of consciousness, and severe hypoxia-hypercapnia. MRI demonstrated transient diffusion hyperintensity in the left frontal-parietal-occipital regions resulting in a permanent infarction in the primary motor area. Later, a brain perfusion SPECT showed persistent diffuse hypoperfusion in the territories involved in diffusion-weighted imaging alteration. Migrainous infarction, depending on the co-occurrence of 2 strictly related phenomena, CSD and hypoxia, appears to be the most plausible explanation. Brain SPECT hypoperfusion suggests a more extensive permanent neuronal loss in territories affected by aura. CF may be then a risk factor for hemiplegic migraine and stroke since bouts of coughing can facilitate brain hypoxia, triggering auras.  相似文献   
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