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91.
92.
Retroviral gag proteins, as well as fragments minimally containing the capsid (CA) and nucleocapsid (NC) subunits of Gag, are able to spontaneously assemble into virus-like particles (VLPs). This occurs in mammalian and bacterial cells as well as in in vitro systems. In every circumstance, nucleic acids are incorporated into the forming particles. Here, we took advantage of an in vitro system for the generation of non-enveloped Mason-Pfizer monkey virus (M-PMV) VLPs derived from a self-assembling CA-NC subunit of Gag. These VLPs were modified through N-terminal extension of CA-NC with short oligopeptides that, after the assembly process, were exposed on the surface of VLPs. The employed N-terminal modifications allowed specific interaction with target cells expressing prostate-specific membrane antigen. Using this system, we were able to incorporate selected siRNA into forming VLPs and deliver it into the cytosol of target cells. In comparison with other viral vectors designed for targeted transgene delivery, this M-PMV VLP system represents the lowest risk of generating virus-associated pathology, as the VLPs do not contain any viral coding sequences and are formed in a cell-free system. 相似文献
93.
The presented research was aimed at finding a suitable tool and procedure for monitoring undercuts or other problems such as cutting without abrasive or inappropriate parameters of the jet during the abrasive water jet (AWJ) cutting of hard-machined materials. Plates of structural steel RSt 37-2 of different thickness were cut through by AWJ with such traverse speeds that cuts of various qualities were obtained. Vibrations of the workpiece were monitored by three accelerometers mounted on the workpiece by a special block that was designed for this purpose. After detecting and recording vibration signals through the National Instruments (NI) program Signal Express, we processed this data by means of the LabVIEW Sound and Vibration Toolkit. Statistical evaluation of data was performed, and RMS was identified as the parameter most suitable for online vibration monitoring. We focus on the analysis of the relationship between the RMS and traverse speed. 相似文献
94.
Sergey Lyulin Pavel Balaev Koushik Narayan Subramanyam Denis Ivliev Abhishek Vasant Mundargi 《Clinics in Orthopedic Surgery》2022,14(1):148
BackgroundThe aim of this study was to explore the role of three-dimensional (3D) endoscopy in surgical management of metastatic disease of the dorsal and lumbar spine.MethodsThis is a prospective study on 33 patients (15 men and 18 women, mean age of 61.6 ± 8.9 years) with biopsy-proven metastatic disease of the spine managed by sequential/staged posterior decompression-stabilization, followed by 3D endoscopy-assisted anterior corpectomy and stabilization with a mesh cage. All patients had significant extradural compression or spinal instability or both. Sixteen patients had neurological deficits. Visual analog scale (VAS), Frenkel grade (neurological deficits), Karnofsky performance status scale, and the 36-item short-form health survey (SF-36) were used for assessment preoperatively and at 3, 6, and 12 months from surgery.ResultsAt a mean follow-up of 1.7 ± 0.7 years from surgery, 18 patients were alive. VAS showed significant improvement at the latest follow-up compared to preoperative levels (4.39 vs. 6.61, p = 0.001). Karnofsky status did not show any significant improvement. Frenkel grade improved in 5 patients, deteriorated in 4 patients, and remained unchanged in 24 patients. Regarding SF-36 parameters, general health showed deterioration, but role functioning—physical, role functioning—emotional, social functioning, and body pain showed statistically significant improvement. There was no change in physical health, viability, and mental health. Subjectively the surgeons felt better depth perception and smoother surgical experience with the 3D optics technology. The only complication was delayed wound healing in three patients who had a previous history of radiotherapy to the surgical site.Conclusions3D endoscopy is a valuable tool in the management of metastatic spinal disease requiring excision and reconstruction using the combined posterior and anterior approaches. These early results warrant confirmation with more data and longer follow-ups. 相似文献
95.
96.
Bulbena-Cabre Andrea DiGenova Patrick Sigel Pavel Dunn Norma Ramos Swift Ronnie Gorman 《International journal of mental health and addiction》2020,18(3):582-586
International Journal of Mental Health and Addiction - The use of synthetic cannabinoids (SCs) has been steadily increasing in recent years and represents a new class of substances of abuse.... 相似文献
97.
Formánek Martin Walderová Radana Baníková Šárka Chmelová Irina Formánková Debora Zeleník Karol Komínek Pavel 《European archives of oto-rhino-laryngology》2020,277(3):933-938
European Archives of Oto-Rhino-Laryngology - Electrical stimulation-supported therapy is an often used modality. However, it still belongs to experimental methods in the human larynx. Data are... 相似文献
98.
Vassiliy A. Medvedev Ilya E. Kolesnikov Pavel K. Olshin Mikhail D. Mikhailov Alina A. Manshina Daria V. Mamonova 《Materials》2022,15(7)
Optical materials doped with several lanthanides are unique in their properties and are widely used in various fields of science and technology. The study of these systems provides solutions for noncontact thermometry, bioimaging, sensing technology, and others. In this paper, we report on the demonstration of YVO4 nanoparticles doped with one, two, and three different rare earth ions (Tm3+, Er3+, and Nd3+). We discuss the morphology, structural properties, and luminescence behavior of particles. Luminescence decay kinetics reveal the energy transfer efficiency (up to 78%) for different ions under the selective excitation of individual ions. Thus, we found that the energy transition from Tm3+ is more favorable than from Er3+ while we did not observe any significant energy rearrangement in the samples under the excitation of Nd3+. The observed strong variation of REI lifetimes makes the suggested nanoparticles promising for luminescent labeling, anticounterfeiting, development of data storage systems, etc. 相似文献
99.
Sergey Grigoriev Anton Smirnov Nestor Washington Solis Pinargote Oleg Yanushevich Natella Kriheli Olga Kramar Yuri Pristinskiy Pavel Peretyagin 《Materials》2022,15(7)
This paper presents a study of Al2O3–ZrO2 (ZTA) nanocomposites with different contents of reduced graphene oxide (rGO). The influence of the rGO content on the physico-mechanical properties of the oxide composite was revealed. Graphene oxide was obtained using a modified Hummers method. Well-dispersed ZTA-GO nanopowders were produced using the colloidal processing method. Using spark plasma sintering technology (SPS), theoretically dense composites were obtained, which also reduced GO during SPS. The microstructure, phase composition, and physico-mechanical properties of the sintered composites were studied. The sintered ZTA composite with an in situ reduced graphene content of 0.28 wt.% after the characterization showed improved mechanical properties: bending strength was 876 ± 43 MPa, fracture toughness—6.8 ± 0.3 MPa·m1/2 and hardness—17.6 ± 0.3 GPa. Microstructure studies showed a uniform zirconia distribution in the ZTA ceramics. The study of the electrical conductivity of reduced graphene oxide-containing composites showed electrical conductivity above the percolation threshold with a small content of graphene oxide (0.28 wt.%). This electrical conductivity makes it possible to produce sintered ceramics by electrical discharge machining (EDM), which significantly reduces the cost of manufacturing complex-shaped products. Besides improved mechanical properties and EDM machinability, 0.28 wt.% rGO composites demonstrated high resistance to hydrothermal degradation. 相似文献
100.
An efficient and versatile synthesis of the naturally occurring C-prenylated stilbenoid methyl ethers and their synthetic analogues is presented. The synthesis represents a six step convergent process including an optimised C-prenylation method. Furthermore, during the demethylation process, six new dihydro-benzopyranyl derivatives were obtained and isolated.An efficient and versatile synthesis of the naturally occurring C-prenylated stilbenoid methyl ethers and synthetic analogs has been developed. 相似文献