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BACKGROUND: The role of inflammation in patients with coronary artery disease is emerging. We sought to assess the profile and outcomes of patients with a clinical syndrome of severe systemic inflammation that led to a diagnosis of suspected sepsis in the setting of acute myocardial infarction complicated by cardiogenic shock (CS). METHODS: Patients enrolled in the randomized SHOCK (SHould we emergently revascularize Occluded Coronaries for cardiogenic shocK) trial (n = 302) were divided into those with clinical signs of severe systemic inflammation (eg, fever [94%] or leukocytosis [72%]) that led to a diagnosis of suspected sepsis (n = 54 [18%]) and those without suspected sepsis (controls; n = 243 [80%]). The patients with suspected sepsis were then further subdivided into those who were considered to be potentially infectious (positive culture result ["culture-positive"]; n = 40) and those who were not (negative culture result ["culture-negative"]; n = 14). RESULTS: Severe systemic inflammation was diagnosed 4 and 2 days after the onset of CS in culture-positive and culture-negative patients, respectively. Patients who developed systemic inflammation tended to be younger (P = .05) and to have lower systemic vascular resistance (SVR) near the onset of CS (P = .006). Many culture-positive patients (40%) had undergone coronary artery bypass graft surgery. However, the lower the initial SVR, the higher the risk of developing culture-positive systemic inflammation (P = .01), even after controlling for age and coronary artery bypass graft surgery. A time-dependent model, adjusted for age, showed that culture-positive patients were at significantly higher risk for death than were controls (hazard ratio, 2.22; 95% confidence interval, 1.32-3.76; P = .008). CONCLUSIONS: Almost one fifth of patients with acute myocardial infarction complicated by CS showed clinical signs of severe systemic inflammation, and those who were culture-positive for sepsis had twice the risk of death. The observation of lower SVR at the onset of shock in patients who subsequently had culture-positive systemic inflammation suggests that inappropriate vasodilation may play an important role in the pathogenesis and persistence of shock and in the risk of infection.  相似文献   
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Metastatic breast cancer remains one of the leading causes of death in women and identification of novel treatment targets is therefore warranted. Functional studies showed that the RNA helicase DDX3 promotes metastasis, but DDX3 expression was never studied in patient samples of metastatic cancer. In order to validate previous functional studies and to evaluate DDX3 as a potential therapeutic target, we investigated DDX3 expression in paired samples of primary and metastatic breast cancer. Samples from 79 breast cancer patients with distant metastases at various anatomical sites were immunohistochemically stained for DDX3. Both cytoplasmic and nuclear DDX3 expression were compared between primary and metastatic tumors. In addition, the correlation between DDX3 expression and overall survival was assessed. Upregulation of cytoplasmic (28%; OR 3.7; p?=?0.002) was common in breast cancer metastases, especially in triple negative (TN) and high grade cases. High cytoplasmic DDX3 levels were most frequent in brain lesions (65%) and significantly correlated with high mitotic activity and triple negative subtype. In addition, worse overall survival was observed for patients with high DDX3 expression in the metastasis (HR 1.79, p?=?0.039). Overall, we conclude that DDX3 expression is upregulated in distant breast cancer metastases, especially in the brain and in TN cases. In addition, high metastatic DDX3 expression correlates with worse survival, implying that DDX3 is a potential therapeutic target in metastatic breast cancer, in particular in the clinically important group of TN patients.  相似文献   
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DDX3X (DDX3), a human RNA helicase, is over expressed in multiple breast cancer cell lines and its expression levels are directly correlated to cellular aggressiveness. NZ51, a ring-expanded nucleoside analogue (REN) has been reported to inhibit the ATP dependent helicase activity of DDX3. Molecular modeling of NZ51 binding to DDX3 indicated that the 5:7-fused imidazodiazepine ring of NZ51 was incorporated into the ATP binding pocket of DDX3. In this study, we investigated the anticancer properties of NZ51 in MCF-7 and MDA-MB-231 breast cancer cell lines. NZ51 treatment decreased cellular motility and cell viability of MCF-7 and MDA-MB-231 cells with IC50 values in the low micromolar range. Biological knockdown of DDX3 in MCF-7 and MDA-MB-231 cells resulted in decreased proliferation rates and reduced clonogenicity. In addition, NZ51 was effective in killing breast cancer cells under hypoxic conditions with the same potency as observed during normoxia. Mechanistic studies indicated that NZ51 did not cause DDX3 degradation, but greatly diminished its functionality. Moreover, in vivo experiments demonstrated that DDX3 knockdown by shRNA resulted in reduced tumor volume and metastasis without altering tumor vascular volume or permeability-surface area. In initial in vivo experiments, NZ51 treatment did not significantly reduce tumor volume. Further studies are needed to optimize drug formulation, dose and delivery. Continuing work will determine the in vitro-in vivo correlation of NZ51 activity and its utility in a clinical setting.  相似文献   
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BACKGROUND AND AIMS OF THE STUDY: Closed mitral commissurotomy (CMC) is a well-established method for treatment of rheumatic mitral stenosis, but outcome in patients with severe pulmonary arterial hypertension (PAH) has not been clearly documented. METHODS: Between April 1996 and October 1999, among 61 patients who underwent CMC, 27 had severe PAH (systolic pressure > 100 mmHg). Of these patients, 11 were in NYHA class III, and 16 were in class IV. Preoperatively, the mean pulmonary artery (PA) pressure was 107.85 +/- 5.74 mmHg (range: 100-118 mmHg), mitral valve area (MVA) 0.704 +/- 0.106 cm2 (range: 0.5-0.91 cm2), and transmitral gradient 11.93 +/- 1.54 mmHg (range: 10-15 mmHg). The echocardiographic mitral valve score was 6.37 +/- 1.11 (range: 6-10). RESULTS: There was no operative mortality or incidence of significant (> or = 2+) post-CMC mitral regurgitation or cerebrovascular accident. The MVA increased to 2.385 +/- 0.248 cm2 (range: 1.9-2.8 cm2), the transmitral gradient fell to 2.44 +/- 0.51 mmHg (range: 2-3 mmHg), and postoperative PA systolic pressure fell to 33.33 +/- 8.20 mmHg (range: 30-60 mmHg). During a mean follow up of 26.9 months (range: 11-51 months), 23 patients were in NYHA class I and four were in class II. There were no significant differences in parameters between sexes, but mean male age was five years less than mean female age. CONCLUSION: In the subset of patients with severe PAH, surgical CMC is a safe and effective procedure that results in greater MVA and a more significant and sustained fall in PA pressure compared with reported series of percutaneous balloon mitral valvuloplasty.  相似文献   
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To address mitochondrial dysfunction that mediates irreversible visual loss and neurodegeneration of the optic nerve in the experimental autoimmune encephalomyelitis (EAE) animal model of multiple sclerosis (MS), mice sensitized for EAE were vitreally injected with self-complementary adenoassociated virus (scAAV) containing the NADH-dehydrogenase type-2 (NDI1) complex I gene that quickly expressed in mitochondria of almost all retinal ganglion cells (RGCs). Visual function assessed by pattern electroretinograms (PERGs) reduced by half in EAE showed no significant reductions with NDI1. Serial optical coherence tomography (OCT) revealed significant inner retinal thinning with EAE that was suppressed by NDI1. Although complex I activity reduced 80% in EAE was not improved by NDI1, in vivo fluorescent probes indicated mitochondrial oxidative stress and apoptosis of the EAE retina were reduced by NDI1. Finally, the 42% loss of axons in the EAE optic nerve was ameliorated by NDI1. Targeting the dysfunctional complex I of EAE responsible for loss of respiration, mitochondrial oxidative stress and apoptosis may be a novel approach to address neuronal and axonal loss responsible for permanent disability that is unaltered by current disease modifying drugs for MS that target inflammation.  相似文献   
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