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We have previously described potent growth-inhibitory effect of a recombinant adenovirus expressing wild type p53 (AdWTp53) in metastatic prostate cancer cells via activation of cellular p53 pathways. We have extended these observations to analyze the effects of AdWTp53 on primary cultures of radical prostatectomy specimens (RPS) and have also evaluated the gene therapeutic potential of the AdWTp53 in a nude mice model. Infection of primary cultures of prostate cancer specimens resulted in about 80% cell growth inhibition in comparison with cultures treated with control adenovirus dl312. Single injection of AdWTp53 into pre-established tumor nodules of DU145 prostate cancer cells suppressed tumor growth significantly (p = 0.0407) as determined by comparison of tumor volumes of the AdWTp53-treated vs. control vector (dl312) or PBS-treated groups. Moreover, there was no significant difference in tumor growth inhibition between single vs. multiple injections of AdWTp53. Our observations support the potential of AdWTp53 for gene therapy of prostate cancer. Int. J. Cancer 71:377-382, 1997. © 1997 Wiley-Liss Inc.  相似文献   
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Objectives

To investigate the value of second-opinion evaluation of multiparametric prostate magnetic resonance imaging (MRI) by subspecialised uroradiologists at a tertiary centre for the detection of significant cancer in transperineal fusion prostate biopsy.

Methods

Evaluation of prospectively acquired initial and second-opinion radiology reports of 158 patients who underwent MRI at regional hospitals prior to transperineal MR/untrasound fusion biopsy at a tertiary referral centre over a 3-year period. Gleason score (GS) 7-10 cancer, positive predictive value (PPV) and negative (NPV) predictive value (±95 % confidence intervals) were calculated and compared by Fisher’s exact test.

Results

Disagreement between initial and tertiary centre second-opinion reports was observed in 54 % of cases (86/158). MRIs had a higher NPV for GS 7-10 in tertiary centre reads compared to initial reports (0.89 ± 0.08 vs 0.72 ± 0.16; p = 0.04), and a higher PPV in the target area for all cancer (0.61 ± 0.12 vs 0.28 ± 0.10; p = 0.01) and GS 7-10 cancer (0.43 ± 0.12 vs 0.2 3 ± 0.09; p = 0.02). For equivocal suspicion, the PPV for GS 7-10 was 0.12 ± 0.11 for tertiary centre and 0.11 ± 0.09 for initial reads; p = 1.00.

Conclusions

Second readings of prostate MRI by subspecialised uroradiologists at a tertiary centre significantly improved both NPV and PPV. Reporter experience may help to reduce overcalling and avoid overtargeting of lesions.

Key Points

? Multiparametric MRIs were more often called negative in subspecialist reads (41 % vs 20 %).? Second readings of prostate mpMRIs by subspecialist uroradiologists significantly improved NPV and PPV.? Reporter experience may reduce overcalling and avoid overtargeting of lesions.? Greater education and training of radiologists in prostate MRI interpretation is advised.
  相似文献   
155.
The Gibbon Ape Leukemia Virus envelope protein (GALV-Env) mediates efficient transduction of human cells, particularly primary B and T lymphocytes, and is therefore of great interest in gene therapy. Using internal domains from murine leukemia viruses (MLV), chimeric GALV-Env proteins such as GALV-C4070A were derived, which allow pseudotyping of lentiviral vectors. In order to improve expression efficiency and vector titers, we developed a codon-optimized (co) variant of GALV-C4070A (coGALV-Env). We found that coGALV-Env mediated efficient pseudotyping not only of γ-retroviral and lentiviral vectors, but also α-retroviral vectors. The obtained titers on HEK293T cells were equal to those with the classical GALV-Env, whereas the required plasmid amounts for transient vector production were significantly lower, namely, 20 ng coGALV-Env plasmid per 106 293T producer cells. Importantly, coGALV-Env-pseudotyped γ- and α-retroviral, as well as lentiviral vectors, mediated efficient transduction of primary human T cells. We propose that the novel chimeric coGALV-Env gene will be very useful for the efficient production of high-titer vector preparations, e.g., to equip human T cells with novel specificities using transgenic TCRs or CARs. The considerably lower amount of plasmid needed might also result in a significant cost advantage for good manufacturing practice (GMP) vector production based on transient transfection.  相似文献   
156.
Multi-resistant pathogens are a serious problem on a considerable scale for the health sector. Patients with infections induced by multi-resistant bacteria cause enormous additional treatment costs of around 20,500 € per insured. Due to the recently used billing and documentation system there is a significant shortage of information transparency. The guidelines for hospital hygiene and infection prevention published by the Robert Koch Institute (RKI) include a presumption provision, which means that subject to compliance with these guidelines the observance of the current state of medical science is suspected. In case of a derogation, a scientific justification is necessary, which is used e.g. in connection with liability questions. Within the framework of legal reforms in 2011, the legislator aspires a nationwide improvement of hygiene quality in medical institutions and information transparency. Many specific issues about the general reporting obligation of infections with multi-resistant pathogens or about the standardized exchange of infection documentations between medical institution and health authority remain unresolved.Regional, cross-sectoral networks create the base to tackle targeted measures collectively and may develop sustainable and tailored solutions for their region. With these considerations in mind, the project HICARE was founded in Mecklenburg-Vorpommern. The project pursues the aim to develop an intervention strategy against the spread of multi-resistant pathogens. Health insurances make an important contribution to quality of medical treatment by participation.  相似文献   
157.
Reactive oxygen species (ROS) have an established role in inflammation and host defense, as they kill intracellular bacteria and have been shown to activate the NLRP3 inflammasome. Here, we find that ROS generated by mitochondrial respiration are important for normal lipopolysaccharide (LPS)-driven production of several proinflammatory cytokines and for the enhanced responsiveness to LPS seen in cells from patients with tumor necrosis factor receptor-associated periodic syndrome (TRAPS), an autoinflammatory disorder caused by missense mutations in the type 1 TNF receptor (TNFR1). We find elevated baseline ROS in both mouse embryonic fibroblasts and human immune cells harboring TRAPS-associated TNFR1 mutations. A variety of antioxidants dampen LPS-induced MAPK phosphorylation and inflammatory cytokine production. However, gp91(phox) and p22(phox) reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunits are dispensable for inflammatory cytokine production, indicating that NADPH oxidases are not the source of proinflammatory ROS. TNFR1 mutant cells exhibit altered mitochondrial function with enhanced oxidative capacity and mitochondrial ROS generation, and pharmacological blockade of mitochondrial ROS efficiently reduces inflammatory cytokine production after LPS stimulation in cells from TRAPS patients and healthy controls. These findings suggest that mitochondrial ROS may be a novel therapeutic target for TRAPS and other inflammatory diseases.  相似文献   
158.
Platelet P2Y12 receptor inhibition plays a pivotal role in preventing thrombotic vascular events in patients with ACS and in patients undergoing percutaneous coronary intervention (PCI). Among the P2Y12 receptor inhibitors, the group of thienopyridines include ticlopidine, clopidogrel and prasugrel, all of which are orally administered prodrugs leading to irreversible P2Y12 receptor inhibition. Non-thienopyridine derivatives including ticagrelor, cangrelor and elinogrel do not require metabolic activation and lead to a reversible P2Y12 receptor inhibition in contrast to thienopyridines. The extend of platelet inhibition is subject to the administered antiplatelet agent and influenced by individual genetic and clinical factors. Insufficient platelet inhibition, termed high platelet reactivity (HPR) is associated with an increased risk for ischemic events after PCI whereas exceeding platelet inhibition results in an increased bleeding risk. Pharmacologic properties and clinical outcome data differ substantially between the existing P2Y12 receptor inhibitors. Whether individualized antiplatelet treatment incorporating different P2Y12 receptor inhibitors improves patients' clinical outcomes warrants further investigation.  相似文献   
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