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51.
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Imre Mäger Emelía Eiríksdóttir Samir EL Andaloussi Ülo Langel 《生物化学与生物物理学报:生物膜》2010,1798(3):338-1672
Cell-penetrating peptides (CPPs) have shown great potency for cargo delivery both in vitro and in vivo. Different biologically relevant molecules need to be delivered into appropriate cellular compartments in order to be active, for instance certain drugs/molecules, e.g. antisense oligonucleotides, peptides, and cytotoxic agents require delivery into the cytoplasm. Assessing uptake mechanisms of CPPs can help to develop novel and more potent cellular delivery vectors, especially in cases when reaching a specific intracellular target requires involvement of a specific internalization pathway. Here we measure the overall uptake kinetics, with emphasis on cytoplasmic delivery, of three cell-penetrating peptides M918, TP10 and pVec using a quenched fluorescence assay. We show that both the uptake levels and kinetic constants depend on the endocytosis inhibitors used in the experiments. In addition, in some cases only the internalization rate is affected by the endocytosis inhibitors while the total uptake level is not and vice versa, which emphasizes importance of kinetic studies when assessing the uptake mechanisms of CPPs. Also, there seems to be a correlation between lower total cellular uptake and higher first-order rate constants. Furthermore, this may indicate simultaneous involvement of different endocytic pathways with different efficacies in the internalization process, as hypothesized but not shown earlier in an uptake kinetics assay. 相似文献
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Romics I 《Neurochemistry international》2007,51(5):328-331
One of the most important clinical pharmacological invention in the last decades the role of adrenoreceptors in urological disease. The disorders of emptying the bladder are associated to the urology. Plant extracts efficacy is low, indicated only in mild symptoms, surgery has to be performed in advanced cases. Recognise, discovering the role of adrenoreceptors in the prostate, bladder neck has changed the treatment of benign prostatic hyperplasia. Relieving the muscle tension leads to a better urinary flow, decreased residual urine and less complaints. Combination with 5alpha-reductase inhibitor a better results can be achieved. The inflammation in prostate is a frequent disease of all age of males. Spasm of the bladder neck maintains the complaints additional alpha-blocker treatment combined with antibiotics, anti-inflammatory drugs are the best choice to cure the patients. Alpha-adrenergic receptor can be found in the lower part of ureter as well. To promote the spontaneous expulsion of lower ureter stones, or fragments after ESWL (extracorporal shock wave lithotripsy) the alpha-blockers are highly recommended. 相似文献
55.
The functional state of the Photosystem (PS) II complex in Arabidopsis psbR T-DNA insertion mutant was studied. The ΔPsbR thylakoids showed about 34% less oxygen evolution than WT, which correlates with the amounts of PSII estimated from YDox radical EPR signal. The increased time constant of the slow phase of flash fluorescence (FF)-relaxation and upshift in the peak position of the main TL-bands, both in the presence and in the absence of DCMU, confirmed that the S2QA− and S2QB− charge recombinations were stabilized in ΔPsbR thylakoids. Furthermore, the higher amount of dark oxidized Cyt-b559 and the increased proportion of fluorescence, which did not decay during the 100s time span of the measurement thus indicating higher amount of YD+QA− recombination, pointed to the donor side modifications in ΔPsbR. EPR measurements revealed that S1-to-S2-transition and S2-state multiline signal were not affected by mutation. The fast phase of the FF-relaxation in the absence of DCMU was significantly slowed down with concomitant decrease in the relative amplitude of this phase, indicating a modification in QA to QB electron transfer in ΔPsbR thylakoids. It is concluded that the lack of the PsbR protein modifies both the donor and the acceptor side of the PSII complex. 相似文献
56.
Development and Evaluation of Methods To Detect Nucleopolyhedroviruses in Larvae of the Douglas-Fir Tussock Moth, Orgyia pseudotsugata (McDunnough) 下载免费PDF全文
Christine M. Thorne Imre S. Otvos Nicholas Conder David B. Levin 《Applied microbiology》2007,73(4):1101-1106
Various molecular methods are used to detect pathogenic microorganisms and viruses within their hosts, but these methods are rarely validated by direct comparison. Southern hybridization, enzyme-linked immunosorbent assay (ELISA), and a novel DNA extraction/PCR assay were used to detect Orgyia pseudotsugata multiple nucleopolyhedrovirus (OpMNPV) in Douglas-fir tussock moth larvae. PCR was more sensitive than Southern hybridization and ELISA at detecting semipurified virus. ELISA, however, was the most accurate method for detecting virus within larvae, given that Southern hybridization and PCR produced false-negative results (31% and 2.5%, respectively). ELISA may be preferable in some applications because virus infections can be quantified (r2 = 0.995). These results may be applicable to both applied and academic research that seeks to accurately identify the incidence of viruses and microorganisms that regulate insect populations. 相似文献
57.
Agata Jakubowska Monique M. van Oers Imre S. Otvos Just M. Vlak 《Virologica Sinica》2007,22(4):257-265
The Douglas-fir tussock moth Orgyia pseudotsugata (Lepidoptera: Lymantriidae) is a frequent defoliator of Douglas-fir and true firs in western USA and Canada. A single nucleopolyhedrovirus (SNPV) isolated from O. pseudotsugata larvae in Canada (OpSNPV) was previously analyzed via its polyhedrin gene, but is phylogenetic status was ambiguous. Sequences of four conserved baculovirus genes, polyhedrin, lef-8, pif-2 and dpol, were amplified from OpSNPV DNA in polymerase chain reactions using degenerate primer sets and their sequences were analyzed phylogenetically. The analysis revealed that OpSNPV belongs to group Ⅱ NPVs and is most closely related to SNPVs that infect O. ericae and O. anartoides, respectively. These results show the need for multiple, concatenated gene phylogenies to classify baculoviruses. 相似文献
58.
Ilma R Korponay-Szabó Katalin Szabados Jánosné Pusztai Katalin Uhrin éva Ludmány éva Nemes Katri Kaukinen Anikó Kapitány Lotta Koskinen Sándor Sipka Anikó Imre Markku M?ki 《BMJ (Clinical research ed.)》2007,335(7632):1244-1247
Objective To evaluate the feasibility and diagnostic accuracy of screening for coeliac disease by rapid detection of IgA antibodies to tissue transglutaminase performed in primary care.Design District nurses screened 6 year old children using rapid antibody testing of finger prick blood. They also collected capillary blood samples for laboratory determination of IgA and IgG antibodies to endomysium and IgA antibodies to tissue transglutaminase. Children with positive rapid test results were directly sent for biopsy of the small intestine.Setting Primary care in Jász-Nagykun-Szolnok county, Hungary.Participants 2690 children (77% of 6 year olds living in the county) and 120 nurses.Main outcome measures Positivity for antibodies to endomysium or transglutaminase in the laboratory and coeliac disease confirmed at biopsy.Results 37 children (1.4%, 95% confidence interval 0.9% to 1.8%) had biopsy confirmed coeliac disease. Only five of these children had been diagnosed clinically before screening. Rapid testing had a 78.1% sensitivity (70.0% to 89.3%) and 100% specificity (88.4% to 100%) for a final diagnosis of coeliac disease by biopsy. Sensitivity was 65.1% (50.2% to 77.6%) and specificity was 100% (99.8% to 100%) compared with combined results of IgA and IgG laboratory tests. Trained laboratory workers detected 30 of the 31 newly diagnosed IgA competent patients with the rapid test kit used blindly. Median time to biopsy after a positive rapid test result was significantly shorter (20 days, range 4-148) than after a positive laboratory result (142 days, 70-256; P<0.001). Children with coeliac disease detected at screening were smaller and had worse health status than their peers but they improved on a gluten-free diet.Conclusions A simple rapid antibody test enabled primary care nurses to detect patients with coeliac disease in the community who were not picked up in clinical care. Extra training is needed to improve sensitivity. 相似文献
59.
Cicek C Karatas T Altuglu I Koturoglu G Kurugol Z Bilgic A 《The new microbiologica》2007,30(2):113-118
The aim of the study was to compare an enzyme immunoassay method with shell vial cell culture method for detection of rotavirus in fecal specimens. In addition, the correlation between laboratory results and clinical scores of patients with gastroenteritis was evaluated. A total of 219 fecal specimens from children (ages 3 weeks to 5 years) with acute gastroenteritis submitted to pediatric emergency room were evaluated by both ELISA and shell vial cell culture. A Vesikari score was used for assessing the severity of the illness. Among 219 stool samples tested, 107 (48.9%) were determined to be positive. Two specimens were positive by shell vial cell culture method while they were ELISA negative. According to these results the calculated sensitivity, specificity, PPV, and NPV of ELISA were 98.1%, 100%, 100%, and 98.2%, respectively. The mean severity score for the 107 episodes of rotavirus diarrhoea was 11.0 +/- 3.6 compared to 4.5 +/- 1.9 for the 112 episodes of non-rotavirus diarrhea in the same population. Our study indicates that ELISA, which is easier to perform, faster and cheaper than cell culture methods may be suitable for routine diagnosis of rotavirus infections. The severity of rotavirus positive gastroenteritis was significantly higher than that of rotavirus negative patients. 相似文献
60.
Rescue and production of vaccine and therapeutic adenovirus vectors expressing inhibitory transgenes
Gall JG Lizonova A EttyReddy D McVey D Zuber M Kovesdi I Aughtman B King CR Brough DE 《Molecular biotechnology》2007,35(3):263-273
Expression of certain transgenes from an adenovirus vector can be deleterious to its own replication. This can result in the
inhibition of virus rescue, reduced viral yields, or, in the worst case, make it impossible to construct a vector expressing
the inhibiting transgene product. A gene regulation system based on the tet operon was used to allow the rescue and efficient growth of adenovectors that express transgenes to high levels. A key advantage
to this system is that repression of transgene expression is mediated by the packaging cell line, thus, expression of regulatory
products from the adenovector are not required. This provides a simple, broadly applicable system wherein transgene repression
is constitutive during vector rescue and growth and there is no effect on adenovector-mediated expression of gene products
in transduced cells. Several high-level expression vectors based on first- and second-generation adenovectors were rescued
and produced to high titer that otherwise could not be grown. Yields of adenovectors expressing inhibitory transgene products
were increased, and the overgrowth of cultures by adenovectors with nonfunctional expression cassettes was prevented. The
gene regulation system is a significant advancement for the development of adenovirus vectors for vaccine and other gene transfer
applications. 相似文献