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71.
Pellinen R Hakkarainen T Wahlfors T Tulimäki K Ketola A Tenhunen A Salonen T Wahlfors J 《International journal of oncology》2004,25(6):1753-1762
Lentiviruses have been used as gene transfer vectors for almost 10 years and their utility has been demonstrated in a variety of different applications. However, their value in cancer gene therapy has not been studied thoroughly. Here we show that VSV-G pseudotyped HIV-1-based lentiviruses are efficient vectors for human tumor cells in vitro and in vivo. Lentiviral gene transfer efficiency was demonstrated by transducing 42 different cell lines, representing 10 different human tumor types. It was shown that most of the cell lines were good or excellent targets for lentiviral transduction, allowing 50-95% gene transfer efficiency. These results were comparable to those obtained with an E1/E3 deleted, serotype 5 adenovirus vector. Analysis of lentivirus vector structure revealed that virus particles devoid of HIV-1 accessory proteins appeared to be more efficient, but the presence of enhancing elements cPPT and WPRE did not play a major role in transduction efficiency to four different human tumor cell lines. However, their effect on the gene expression level in these cells was apparent. To examine the impact of lentiviral gene expression level on suicide gene therapy approach, human osteosarcoma cells were transduced with lentivirus- or adenovirus vectors carrying the fusion gene HSV-TK-GFP and exposed to ganciclovir. Cell viability analysis after the treatment revealed that both vector types induced similar level of cytotoxicity, suggesting that lentiviral expression of a suicide gene is adequate for tumor cell destruction. Finally, in vivo transduction studies with subcutaneous tumors showed that lentivirus vectors can yield similar gene transfer efficiency than adenovirus vector, despite three orders of magnitude lower titer of the lentiviral preparation. In conclusion, these data show that lentiviruses are efficient gene transfer vehicles for human tumor cells and justify their use in further preclinical cancer gene therapy studies. 相似文献
72.
Ojala K Koski J Ernst W Grabherr R Jones I Oker-Blom C 《Technology in cancer research & treatment》2004,3(1):77-84
Improved display of foreign protein moieties in combination with beneficial alteration of the viral surface properties should be of value for targeted and enhanced gene delivery. Here, we describe a vector based on Autographa californica multiple nucleopolyhedrovirus (AcMNPV) displaying synthetic IgG-binding domains (ZZ) of protein A fused to the transmembrane anchor of vesicular stomatitis virus (VSV) G protein. This display vector was equipped with a GFP/EGFP expression cassette enabling fluorescent detection in both insect and mammalian cells. The virus construct displayed the biologically active fusion protein efficiently and showed increased binding capacity to IgG. As the display is carried out using a membrane anchor of foreign origin, gp64 is left intact for virus entry, which may increase gene expression in the transduced mammalian cells. In addition, the viral vector can be targeted to any desired cell type via binding of ZZ domains when an appropriate IgG antibody is available. 相似文献
73.
Breast milk fatty acids,eicosanoids, and cytokines in mothers with and without allergic disease 总被引:3,自引:0,他引:3
Laiho K Lampi AM Hamalainen M Moilanen E Piironen V Arvola T Syrjanen S Isolauri E 《Pediatric research》2003,53(4):642-647
Allergic disease (AD), including atopic eczema, asthma, allergic rhinitis, and food allergy, is characterized by an imbalance between cytokines produced by distinct T-helper cell subtypes. Whether this imbalance can be transferred from mother to breast milk remains to be established. The objective was to investigate the concentrations and interactions of nutritional and inflammatory factors in breast milk. Breast milk samples were collected from mothers with AD (n = 43) and without AD (n = 51). The concentrations of transforming growth factor (TGF)-beta2, tumor necrosis factor-alpha, IL-4, IL-10, prostaglandin E2, and cysteinyl leukotrienes were measured by immunoassays and fatty acid composition by gas chromatography. Mothers with AD had a lower concentration of TGF-beta2 in breast milk [median (interquartile range), 420 (278-701) ng/L] compared with those without AD [539 (378-1108) ng/L; p = 0.003], whereas other cytokines, prostaglandin E2, and cysteinyl leukotriene concentrations or fatty acid composition were not significantly different between the groups. The breast milk inflammatory factors and fatty acid composition were shown to be related. A positive association was observed between TGF-beta2 and the proportion of polyunsaturated fatty acids (p = 0.038) and a negative association between TGF-beta2 and the proportion of saturated fatty acids (p = 0.029) in breast milk. The reduced TGF-beta2 concentration in the breast milk of mothers with AD may interfere with the development of the mucosal immune system of the breast-fed infant. The observed associations between nutritional and inflammatory factors in breast milk suggest that it may be possible to influence the immunologic properties of breast milk by dietary intervention of the mother. 相似文献
74.
Kinnula VL Soini Y Kvist-Mäkelä K Savolainen ER Koistinen P 《Antioxidants & redox signaling》2002,4(1):27-34
Neutrophils have a short half-life and high tendency to undergo apoptosis. One feature that may influence these characteristics is the antioxidant/oxidant balance of these cells. There are few studies on the levels of antioxidant enzymes in human neutrophils. We have analyzed by immunohistochemistry of paraffin-embedded cells and from cytospin preparations the most important antioxidant proteins in human neutrophils, and compared their levels with those in blood monocytes. Neutrophils showed moderate to high catalase, weak to moderate extracellular superoxide dismutase, and weak copper zinc superoxide dismutase and gamma-glutamylcysteine synthetase immunoreactivities. There were no detectable levels of manganese superoxide dismutase, thioredoxin, and heme oxygenase 1. Some differences were observed between the samples prepared by embedding in paraffin or by cytospin. These results, in combination with a recent study from this laboratory, suggest that a prominent feature in neutrophils is their high catalase activity but lower level of glutathione-dependent antioxidant enzymes. The differences in antioxidant profiles in neutrophils and monocytes may have important effects on the life span of human neutrophils, in both healthy and diseased tissues. 相似文献
75.
Erkki?Isomets?Email author Kirsi?Suominen Outi?Mantere Hanna?Valtonen Sami?Lepp?m?ki Marita?Pippingsk?ld Petri?Arvilommi 《BMC psychiatry》2003,3(1):8
Background
We investigated our translation of The Mood Disorder Questionnaire (MDQ) as a screening instrument for bipolar disorder in a psychiatric setting in Finland. 相似文献76.
Järvenpää T Räihä I Kaprio J Koskenvuo M Laine M Kurki T Vahlberg T Viljanen T Ahonen K Rinne JO 《Dementia and geriatric cognitive disorders》2003,16(4):245-252
We investigated regional cerebral glucose metabolic rates (rCMRgluc) with positron emission tomography using 2-[18F]fluoro-2-deoxy-D-glucose (FDG) in 7 monozygotic twin pairs discordant for Alzheimer's disease (AD). Ten healthy volunteers with comparable mean age and educational level served as controls. In the hippocampus, the mean +/- SD rCMRgluc were 0.20 +/- 0.03 micromol/ml/min for the demented twins, 0.21 +/- 0.03 micromol/ml/min for their non-demented co-twins, and 0.23 +/- 0.02 micromol/ml/min for the controls. The mean hippocampal rCMRgluc was reduced in the demented twins (p = 0.006), compared with the controls. In the lateral temporal cortex, the mean +/- SD rCMRgluc were 0.27 +/- 0.05, 0.28 +/- 0.04, and 0.32 +/- 0.02 micromol/ml/min, respectively. These mean rates were reduced both in the demented (p = 0.02) and the non-demented (p = 0.01) twins, compared with the controls. In conclusion, in the demented twins, the reduction of rCMRgluc was detected in the hippocampus and lateral temporal cortex, i.e. the 2 brain areas which show early changes in pathological and imaging studies in AD. Their non-demented co-twins showed milder reductions, which may be an indication of genetic susceptibility for dementia, and an early sign of a dementing illness in them. 相似文献
77.
Antikainen R Hänninen T Honkalampi K Hintikka J Koivumaa-Honkanen H Tanskanen A Viinamäki H 《European archives of psychiatry and clinical neuroscience》2001,251(1):6-11
Background The aim was to examine associations between memory complaints, cognitive performance and mood in 174 adult, clinically depressed,
neurologically healthy patients at baseline and during six months of follow-up.
Methods Subjective memory disturbance was assessed using the Memory Complaint Questionnaire (MCQ). Levels of cognitive function,
including memory, were assessed using a battery of neuropsychological tests. Mood and personality traits were assessed using
rating scales, including the Beck Depression Inventory (BDI), Hamilton Depression Rating Scale (HDRS) and the 90-item Symptom
Check List (SCL-90).
Results At baseline, patients complaining of memory disturbances had higher BDI and HDRS scores than patients not complaining of
memory problems. They also did less well in objective memory performances but not in other cognitive functions. Complaints
of memory problems decreased during the follow-up. This change was associated with mood improvement and with reductions in
other mental symptoms but not with changes in cognitive performance. In logistic regression analysis factors independently
associated with MCQ change were age (OR 0.96) and BDI change (OR 1.06).
Conclusions Subjective memory problems usually decline if depression is alleviated.
Received: 3 February 2000 / Accepted: 26 October 2000 相似文献
78.
Kirsi Talala Taina Huurre Hillevi Aro Tuija Martelin Ritva Prättälä 《Social psychiatry and psychiatric epidemiology》2009,44(10):871-879
Background
Socio-economic differences in depressive symptoms are well reported, but there are only few studies concerning changes in these differences over time. The aim of this study was to assess trends in socio-economic differences in self-reported depression over the time period 1979–2002 in Finland. 相似文献79.
Mirkka Rantanen Tapio Kallio Kirsi Johansson Sanna Salanter? Heli Virtanen Helena Leino-Kilpi 《Nephrology nursing journal》2008,35(3):249-55; quiz 256
In order to be empowered in different situations related to dialysis care, patients need knowledge. This study describes the knowledge expectations of patients on dialysis treatment (n = 47) and selected background variables. The results indicated that patients expressed moderate knowledge expectations. Most important were the biophysiological, functional, and ethical dimensions of knowledge. The least important were the social and experiential dimensions of knowledge. Patients' age, employment status, dialysis modality, and length of dialysis were positively correlated with knowledge expectations. 相似文献
80.
Kirsi Vitikainen Miika Linna Andrew Street 《The European journal of health economics》2010,11(4):395-404
Substitution of inpatient for outpatient care is seen as a means to increase patient throughput and control costs. The purpose of this study was to assess the impact of increased outpatient care on hospital costs and efficiency using Finnish specialty-level data from years 2003–2006 to which we applied stochastic frontier analysis. The results reveal that outpatient services have a smaller impact on total costs than inpatient services. At the same time, increased outpatient activity appears to have an adverse effect on estimated cost efficiency. This counterintuitive finding is probably due to the low weight given to outpatient activities by the Diagnosis Related Groups (DRG) system. A common weighting for inpatient and outpatient services is required in order to assess accurately the impact of outpatient care on efficiency. 相似文献