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101.
This study: (i) investigated the in vitro cytotoxicity and mode of action of lurbinectedin (PM01183) and Zalypsis® (PM00104) compared with trabectedin in cell lines deficient in specific mechanisms of repair, (ii) evaluated their in vivo antitumor activity against a series of murine tumors and human xenografts. The antiproliferative activity, the DNA damage and the cell cycle perturbations induced by the three compounds on tumor lines were very similar. Nucleotide Excision Repair (NER) deficient cells were approximately fourfold more resistant to trabectedin, lurbinectedin and Zalypsis®. Cells deficient in non‐homologous end joining (NHEJ), MRN complex and translesion synthesis (TLS) were slightly more sensitive to the three compounds (approximately fivefold) while cells deficient in homologous recombination (HR) were markedly more sensitive (150–200‐fold). All three compounds showed a good antitumor activity in several in vivo models. Lurbinectedin and trabectedin had a similar pattern of antitumor activity in murine tumors and in xenografts, whereas Zalypsis® appeared to have a distinct spectrum of activity. The fact that no relationship whatsoever was found between the in vitro cytotoxic potency and the in vivo antitumor activity, suggests that in addition to direct cytotoxic mechanisms other host‐mediated effects are involved in the in vivo pharmacological effects.  相似文献   
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Current perspectives in therapeutic myocardial angiogenesis   总被引:2,自引:0,他引:2  
The complex mechanisms mediating the development of new blood vessels are now beginning to be unraveled. In conjunction with major biotechnology advances, this has facilitated the initiation of translational research related to a novel treatment strategy for patients with myocardial or leg ischemia due to obstructive arterial disease--therapeutic angiogenesis. At present, at least 17 clinical trials of myocardial angiogenesis have been presented involving over 900 patients. Uncertainty exists as to the optimal delivery route and angiogenic agent, and this uncertainty is reflected in the diverse methodology of the trials published thus far. The majority of patients received an angiogenic protein via the intracoronary route. Other delivery techniques--such as direct intramyocardial injection via transepicardial or transendocardial routes--and other angiogenic agents, including master genes, have also been studied. Most recently, interest has grown in the potential angiogenesis effects of cell therapy--such as autologous bone marrow cells or cultured stem cells--and there are now several groups initiating Phase I/II trials in this area. This review summarizes the current evidence pertaining to the safety, feasibility, and efficacy of various angiogenic techniques aimed at enhancing myocardial blood flow and alleviating angina.  相似文献   
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BACKGROUND/AIMS: Substantial differences about the efficacy of transcatheter arterial chemoembolization for the treatment of hepatocellular carcinoma are reported in literature. This probably depends on the fact that in each single study, different patient selection criteria, type of epidemiological approach, end points adopted and kind of technical approach were used. This study aims to evaluate the efficacy of segmental transcatheter arterial chemoembolization in amelioring patient survival and to determine which patients might really benefit from this treatment. METHODOLOGY: To achieve our goals 193 consecutive patients (110 treated and 83 untreated) were studied. They were selected in the same period of time and matched as far as their demographic and clinical characteristics. RESULTS: Our results demonstrate that both in treated and control patients, Child class, alpha-fetoprotein and tumor diameter significantly influenced survival, resulting important prognostic factors. Transcatheter arterial chemoembolization significantly ameliorated survival in treated patients compared to controls (p < 0.0001). CONCLUSIONS: Transcatheter arterial chemoembolization significantly ameliorates survival in patients with hepatocellular carcinoma. However, the presence of large tumors producing high alpha-fetoprotein levels in patients with advanced Child class should discourage treatment.  相似文献   
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Anagnostou  A; Schade  S; Barone  J; Fried  W 《Blood》1977,50(3):457-462
Studies were performed to determine the effects of partial hepatectomy on extra-renal erythropoietin production. Rats were either partially hepatectomized or sham operated. At intervals of from 5 min to 7 days afterward, both kidneys were removed from cohorts of the above two groups of rats and the animals were then exposed to hypoxia for 7.5 hr. Immediately afterward, their plasma was collected and its erythropoietin titer was assayed. Rats which were partially hepatectomized 2-4 days prior to nephrectomy and hypoxia had significantly higher plasma erythropoietin levels than did sham- operated controls, whereas rats hepatectomized 5 min, 1 day, or 7 days prior to nephrectomy and hypoxia did not. These data are consistent with the conclusion that extrarenal erythropoietin production is enhanced in association with rapid regeneration of hepatic cells.  相似文献   
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Background

Damage to the cardiac conduction system requiring permanent pacemaker (PPM) implantation is a known adverse outcome of transcatheter aortic valve replacement (TAVR). A permanent-temporary pacemaker (PTPM) is a device that involves an active-fixation lead attached to an external pulse generator taped to the skin. We reviewed the utility of PTPMs as a temporary bridge measure after TAVR in patients with conduction abnormalities that do not meet conventional criteria for PPM placement.

Methods

Between January 01, 2013 and December 31, 2015, we analyzed 67 patients who received PTPM after TAVR. Baseline demographics, comorbidities, type and size of the valve, pre-TAVR electrocardiograms (ECGs), post-TAVR ECGs at 1 day, 1 month, and 6 months, and pacemaker interrogation results were reviewed for each patient if available.

Results

The mean age of patients was 80.5?±?9.1 years. PTPM were placed for 2.3?±?2.4 days. Among these patients, 44.8% (n?=?30) received a PPM prior to discharge. Male gender (OR 2.84, 95% CI 1.05–7.69, p?=?0.05) and an increase in QRS duration post-TAVR (p?=?0.01) were associated with PPM placement. Pacemaker interrogation data of 11 patients with PPM revealed that 27% (n?=?3) had <?1% V-pacing requirements and <?10% A-pacing requirements.

Conclusions

In post-TAVR patients who develop conduction abnormalities that do not meet conventional PPM implantation indications, PTPM safely provides a time period for further assessment and may prevent unnecessary PPM implantation. Male gender and an increase in QRS duration post-TAVR are associated with PPM implantation. Additionally, some patients may recover from their conduction disturbances and demonstrate low pacemaker utilization.
  相似文献   
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