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41.
Jibin Guan Hong Guo Tang Tang Yihan Wang Yushuang Wei Punit Seth Yingming Li Scott M. Dehm Erkki Ruoslahti Hong-Bo Pang 《Advanced functional materials》2021,31(24):2100478
Nucleotide-based drugs, such as antisense oligonucleotides (ASOs), have unique advantages in treating human diseases as they provide virtually unlimited ability to target any gene. However, their clinical translation faces many challenges, one of which is poor delivery to the target tissue in vivo. This problem is particularly evident in solid tumors. Here, liposomes are functionalized with a tumor-homing and -penetrating peptide, iRGD, as a carrier of an ASO against androgen receptor (AR) for prostate cancer treatment. The iRGD-liposomes exhibit a high loading efficiency of AR-ASO, and an efficient knockdown of AR gene products is achieved in vitro, including AR splice variants. In vivo, iRGD-liposomes significantly increase AR-ASO accumulation in the tumor tissue and decrease AR expression relative to free ASOs in prostate tumors established as subcutaneous xenografts. Similar results are obtained with intra-tibial xenografts modeling metastasis to bones, the predominant site of metastasis for prostate cancer. In treatment studies, iRGD-liposomes markedly improve the AR-ASO efficacy in suppressing the growth of both subcutaneous xenografts and intra-tibial xenografts. The inhibitory effect on tumor growth is also significantly prolonged by the delivery of the AR-ASO in the iRGD-liposomes. Meanwhile, iRGD-liposomes does not increase ASO accumulation or toxicity in healthy organs. Overall, a delivery system that can significantly increase ASO accumulation and efficacy in solid tumors is provided here. These benefits are achieved without significant side effects, providing a way to increase the antitumor efficacy of ASOs. 相似文献
42.
Erkki Honkanen Aino Pippuri Pekka Kairisalo Heinrich Thaler Maija Koivisto Sirpa Tuomi 《Journal of heterocyclic chemistry》1980,17(4):797-798
A new four step synthesis of prazosin, 2-[4-(2-furoyl)piperazin-l-yl]-4-amino-6,7-dimethoxyquinazoline, has been described. The method is also adaptable for the preparation of other substituted 4-aminoquinazolines. The yields are good in every step and the reactions are performed with ease. Prazosin hydrochloride of high purity is obtained directly in the last step. 相似文献
43.
Investigations of general properties of time evolution of both classical and quantum systems show that the evolution (on a microscopic level) is reversible, and, if there is an approach to equilibrium, it exists only in the sense of weak convergence and necessarily in both directions of time. In this connection attempts to derive irreversibility and the approach to equilibrium in the sense of strong convergence and without any loss of information (using the so-called Lyapunov converters) are discussed. After demonstrating their drawbacks, an alternative approach is proposed based on the spectral properties of the generator of the group. The relevant spectral criteria for the approach of both classical and quantum ensembles to equilibrium are given, and the decisive role of loss of information in obtaining stronger variants of convergence is emphasized. The asymmetry between initial and any other state —consisting of different levels of information needed to prepare the states—is proposed as an adequate explanation of irreversibility. The importance of the method of complex scaling in this context is discussed, and its application in proving some spectral properties in the quantal Hamiltonian formulation is stressed. 相似文献
44.
Jakub Czajkowski Tuukka Pryk?ri Erkki Alarousu Jaakko Palosaari Risto Myllyl? 《Optical Review》2010,17(3):257-262
Application of time domain, ultra high resolution optical coherence tomography (UHR-OCT) in printed electronics products’
quality inspection is demonstrated. Presented study was done using experimental UHR-OCT device based on a Kerr-lens mode locked
Ti:sapphire femtosecond laser, photonic crystal fibre and modified, free-space Michelson interferometer. Possibilities of
the technique are demonstrated by analysis of an RF antenna—example of printed electronics products. Measurements were done
with submicron axial resolution, offered by UHR-OCT system developed in our laboratory. Such high resolution is necessary
due to the thickness of material layers used in printed electronics. In addition to tomography imaging, numerical results
were compared with data provided by two commercially available measurement devices: Wyko NT3300 optical profiler and Dektak
8 stylus profiler (both Veeco). Comparison of profile heights and their spatial correlation is presented. Ability for full
volumetric reconstruction and accuracy justified with reference measurements prove OCT to be a reliable tool in printed electronics
product testing. 相似文献
45.
46.
Laihia K Kolehmainen E Nikiforov V Miltsov S 《Magnetic resonance in chemistry : MRC》2006,44(9):895-900
1H, 13C and 15N NMR chemical shifts and couplings (n)J(H,C) in DMSO-d(6) at 30 degrees C have been determined for 1,2-diaryl-(4E)-arylidene-2-imidazolin-5-one derivatives 1-27. Their chemical shift assignments are based on PFG DQF 1H,1H COSY, PFG 1H,13C HMQC as well as PFG 1H,13C and 1H,15N HMBC experiments. For compounds 1-10 including aryl fluorine substituent(s) also the couplings (n)J(F,C) (n = 1 - 4) are reported. 相似文献
47.
48.
Erkki Rahkamaa 《Molecular physics》2013,111(5):727-731
A small range of compounds contain ions from two transition groups, 3d and 4f. Most of these enter an ordered antiferromagnetic state only at liquid helium temperatures, and the internal fields are 1 tesla or less. Experiments are suggested on various single crystals. Measurements by electron spin resonance on impurity ions in antiferromagnetic dysprosium phosphate show that similar compounds could be used for experiments on nuclear orientation with nuclear magnetic resonance. 相似文献
49.
Erkki Vilkman Eija-Riitta Lauri Paavo Alku Eeva Sala Marketta Sihvo 《Journal of voice》1999,13(2):303-312
The effects of prolonged (5x45 minute) reading (vocal loading) on fundamental frequency (F0), sound pressure level (SPL), subglottal (intraroral) pressure (p), and two glottal flow waveform parameters (AC amplitude of glottal flow, f, and negative peak amplitude of differentiated flow (d) of normal female and male subjects (N = 80) were studied. Two rest (morning and noon) and three loading (two in the morning and one in the afternoon) samples were recorded and analyzed. The glottal waveforms were obtained by inverse filtering of the acoustic pressure waveforms of speaking voice samples. The analyses were based on measurement and inverse filtering of the first stressed syllable of "paappa" words repeated 3x5 times for normal, as soft as possible, and as loud as possible phonation. In normal phonation the parameter values changed statistically significantly due to loading. In many cases the values obtained in the morning samples changed after the first loading session. This is interpreted as a vocal "warming-up effect." Especially in soft phonation p, d, and f were sensitive indicators of vocal loading. In both normal and soft phonation, the SPL, p, d, and f values tended to rise due to prolonged reading in the morning and afternoon samples, indicating increased effort (normal phonation) and a rise in the phonatory threshold (soft phonation). The lunch break vocal rest ("rest effect") considerably affected the parameter values in many cases. 相似文献
50.
Erkki Koivunen 《Journal of chromatography. A》1989,470(2):401-406
Specific chromogenic p-nitroanilide substrates have proved useful for localizing proteolytic enzymes, such as trypsin, chymotrypsin and elastase after separation of agarose gel electrophoresis and when immobilized on nitrocellulose. This procedure was further developed for use with sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). After SDS-PAGE, proteins were transferred electrophoretically to a nitrocellulose membrane. The membrane was incubated for 10–60 min with Bz-Ile-Glu-Gly-Arg-p-nitroanilide as a substrate for detection of trypsin-like proteases and with MeO-Suc-Arg-Pro-Tyr-p-nitroanilide for detection of chymotrypsin. The yellow p-nitroanilide released at the site of proteolytic activity was converted into a visible and stable red azo dye. By this method was identified and determined the molecular weight of a trypsin-like protease that occurs at high concentrations in mucinous ovarian tumour cyst fluid together with its specific inhibitor peptide, tumour-associated trypsin inhibitor (TATI). The method was also used to visualize trypsin and chymotrypsin in human pancreatic juice. Using the trypsin substrate, three proteolytic bands, corresponding to Mr of 22 000, 24 000 and 26 000 daltons, were visualized in pancreatic juice, while the proteolytic zones in cyst fluid had Mr of 25 000 and 28 000 daltons. With the chymotrypsin substrate, a band of 29 000 daltons was visualized in pancreatic juice, whereas no activity was detected in cyst fluid. By incubation of the blotted cyst fluid proteins with 125I-labelled TATI, a pattern of bands at 25 000 and 28 000 daltons was detected identical to that obtained with the chromogenic substrate. 相似文献