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91.
Lebduska P Korb J Tůmová M Heneberg P Dráber P 《Journal of immunological methods》2007,328(1-2):139-151
Immunolabeling of isolated plasma membrane (PM) sheets combined with high-resolution electron microscopy is a powerful technique for understanding the topography of PM-bound signaling molecules. However, this technique has been mostly confined to analysis of membrane sheets from adherent cells. Here we present a rapid, simple and versatile method for isolation of PM sheets from non-adherent cells, and show its use for examination of the topography of Fcepsilon receptor I (FcepsilonRI) and transmembrane adaptors, LAT (linker for activation of T cells) and NTAL (non-T cell activation linker), in murine bone marrow-derived mast cells (BMMC). The data were compared with those obtained from widely used but tumor-derived rat basophilic leukemia (RBL) cells. In non-activated cells, FcepsilonRI was distributed either individually or in small clusters of comparable size in both cell types. In multivalent antigen-activated BMMC as well as RBL cells, FcepsilonRI was internalized to a similar extent, but, strikingly, internalization in BMMC was not preceded by formation of large (~200 nm) aggregates of FcepsilonRI, described previously in activated RBL cells. On the other hand, downstream adaptor proteins, LAT and NTAL, were localized in independent domains in both BMMC and RBL cells before and after FcepsilonRI triggering. The combined data demonstrate unexpected properties of FcepsilonRI signaling assemblies in BMMC and emphasize the importance of studies of PM sheets isolated from non-tumor cells. 相似文献
92.
Kundrát P 《Physics in medicine and biology》2007,52(23):6813-6830
A semi-analytical model of light ions' Bragg peaks is presented and used in conjunction with a detailed probabilistic radiobiological module to predict the biological effectiveness of light ion irradiation for hadrontherapy applications. The physical Bragg peak model is based on energy-loss calculations with the SRIM code and phenomenological formulae for the energy-loss straggling. Effects of nuclear reactions are accounted for on the level of reducing the number of primary particles only. Reaction products are not followed at all and their contribution to dose deposition is neglected. Beam widening due to multiple scattering and calculations of spread-out Bragg peaks are briefly discussed. With this simple physical model, integral depth-dose distributions are calculated for protons, carbon, oxygen and neon ions. A good agreement with published experimental data is observed for protons and lower energy ions (with ranges in water up to approximately 15 cm), while less satisfactory results are obtained for higher energy ions due to the increased role of nuclear reaction products, neglected in this model. A detailed probabilistic radiobiological module is used to complement the simple physical model and to estimate biological effectiveness along the penetration depth of Bragg peak irradiation. Excellent agreement is found between model predictions and experimental data for carbon beams, indicating potential applications of the present scheme in treatment planning in light ion hadrontherapy. Due to the semi-analytical character of the model, leading to high computational speed, applications are foreseen in particular in the fully biological optimization of multiple irradiation fields and intensity-modulated beams. 相似文献
93.
Jian Hua Gu Rulin Qian Robert Chou Pavel V. Bondarenko Merrill Goldenberg 《Pharmaceutical research》2018,35(8):157
Purpose
To show and rationalize the confounding effects on the rotational/oscillatory rheology of surface active impurities in commercial protein formulations such as bovine serum albumin, BSA.Methods
Bulk and interfacial rotational/oscillatory rheology were used to study the viscosity, complex viscosity, storage/elastic modulus, G’ and loss/viscous modulus, G”, as a function of time of aqueous formulations of BSA and their purified components.Results
Viscosity/time profiles at steady shear for different commercial BSA products and lots showed viscosity increase, decrease and time-independent profiles at low shear rates. All lots showed shear thinning. BSA monomer and dimers/aggregates, in general, showed similar profiles. Addition of low levels of surfactant or high shear rates rendered all solutions to be Newtonian-like. Interfacial viscosity studies paralleled those on the rotational rheometer. G’?>?G” with viscosity increase and G’?<?G” with viscosity decrease over time.Conclusions
We provide a rational explanation for the time-dependent and source-dependent rheological behavior of aqueous formulations of commercially available BSA proteins based on the migration of protein and surface active impurities to the air/water interface within the rheometer plates leading to the formation and breakdown of protein networks. Highly purified proteins is warranted in rheological studies of protein drug product candidates.94.
American Journal of Cardiovascular Drugs - SERAPHIN was a double-blind, placebo-controlled, event-driven phase III trial that evaluated the effects of long-term treatment with macitentan, an oral... 相似文献
95.
Skoloudík D Fadrná T Bártová P Langová K Ressner P Zapletalová O Hlustík P Herzig R Kannovský P 《Ultrasound in medicine & biology》2007,33(9):1347-1352
The aim of this study was to evaluate inter-reader, intra-investigator and inter-investigator reproducibility and correlations in the assessment of substantia nigra (SN) echogenicity and area measurement by a physician-sonographer (PS), a sonographic laboratory assistant (SLA) and a physician without sonographic experience (PN). A total of 22 patients with extrapyramidal symptoms were examined using transcranial sonography (TCS). SN images were encoded and evaluated by the three readers. A second TCS examination was performed after 7+/-2 d. A second investigator performed TCS examination 1 mo later. Spearman rank correlation and Pearson's correlation coefficient were used when assessing the agreement between readers. All three readers identified the same 15 patients with SN echogenicity III or more. Inter-reader SN echogenicity and area measurement correlations were r=0.55 to 0.82 and r=0.31 to 0.74 between PS and SLA and r=0.55 to 0.77 and 0.49 to 0.62 between PS and PN, respectively (p<0.05 in all cases). Intra-reader echogenicity and area measurement correlations (r=0.85 to 0.96 and r=0.51 to 0.69) were statistically significant only for PS (p<0.001). All intra- and inter-investigator correlations of SN area measurement (r=0.69 to 0.88 and r=0.5 to 0.61) and SN echogenicity (r=0.64 to 0.92 and r=0.51 to 0.69) were statistically significant (p<0.05). Semiquantitative evaluation of SN echogenicity and area using TCS is highly dependent on the experience of the sonographer. Only an experienced sonographer was able to produce very reproducible results with statistically significant correlations; SLA and PN intra-reader correlations were poor. 相似文献
96.
Background
Ifenprodil as a specific antagonist of NMDA receptors containing a dominant NR2B subunit exhibits age-dependent anticonvulsant action. Possible changes of this action due to status epilepticus (SE) elicited at early stage of development were studied using cortical epileptic afterdischarges (ADs) as a model.Methods
Lithium-pilocarpine SE was induced at postnatal day 12 and effects of ifenprodil were studied 3, 6, 9, and 13?days after SE in rat pups with implanted epidural electrodes. Controls (LiPAR) received saline instead of pilocarpine. ADs were elicited by low frequency stimulation of sensorimotor cortex. Intensity of stimulation current increased in 18 steps from 0.2 to 15?mA. Ifenprodil (20?mg/kg) was administered intraperitoneally (ip) after the stimulation with 3.5-mA current. Threshold for four different phenomena as well as duration of ADs were evaluated.Results
The threshold for the transition into the limbic type of ADs was higher in 15-day-old SE rats than in LiPAR controls. Opposite difference was found in 18-day-old animals, older rats did not exhibit any difference. Isolated significant changes in total duration of ADs were found after high stimulation intensities. These changes appeared in 18-day-old rats where ADs were shorter in SE than in control LiPAR rats.Conclusions
Changes in ifenprodil action were found only in the first week after SE but not in the second week. Interpretation of the results is complicated by failure of significant differences between SE and LiPAR rats probably due to a high dose of paraldehyde. 相似文献97.
98.
Jiří Chomiak Pavel Dungl Martin Ošťádal Monika Frydrychová Michal Burian 《International orthopaedics》2014,38(4):803-810
Purpose
Latissimus dorsi and teres major transfers to the lateral side of the humerus with lengthening of the pectoralis major and subscapularis muscles for residual shoulder deformity were compared in children and skeletally mature patients.Methods
Fifteen patients (nine children, six skeletally mature patients aged three to 30 years, follow-up one to 22 years) were treated for internal shoulder contracture after birth plexus lesions: C5–C6 (seven patients); C5–7 (five patients); C5-C8-T1 (three patients, respectively). Range of movement, Mallet shoulder function score and radiographs were assessed.Results
Pre-operatively, shoulder function restrictions were comparable in all patients. Postoperatively, external rotation, abduction and Mallet function score improved significantly (p < 0.05) in all patients except one. There were no differences in improvement between children and skeletally mature patients (p = 0.24–1.0).Conclusions
This technique improves external rotation and abduction of the shoulder for daily living activities in children and young, skeletally mature, patients. 相似文献99.
100.
Sarah Al-Beltagi Cristian Alexandru Preda Leah V. Goulding Joe James Juan Pu Paul Skinner Zhimin Jiang Belinda Lei Wang Jiayun Yang Ashley C. Banyard Kenneth H. Mellits Pavel Gershkovich Christopher J. Hayes Jonathan Nguyen-Van-Tam Ian H. Brown Jinhua Liu Kin-Chow Chang 《Viruses》2021,13(2)
The long-term control strategy of SARS-CoV-2 and other major respiratory viruses needs to include antivirals to treat acute infections, in addition to the judicious use of effective vaccines. Whilst COVID-19 vaccines are being rolled out for mass vaccination, the modest number of antivirals in use or development for any disease bears testament to the challenges of antiviral development. We recently showed that non-cytotoxic levels of thapsigargin (TG), an inhibitor of the sarcoplasmic/endoplasmic reticulum (ER) Ca2+ ATPase pump, induces a potent host innate immune antiviral response that blocks influenza A virus replication. Here we show that TG is also highly effective in blocking the replication of respiratory syncytial virus (RSV), common cold coronavirus OC43, SARS-CoV-2 and influenza A virus in immortalized or primary human cells. TG’s antiviral performance was significantly better than remdesivir and ribavirin in their respective inhibition of OC43 and RSV. Notably, TG was just as inhibitory to coronaviruses (OC43 and SARS-CoV-2) and influenza viruses (USSR H1N1 and pdm 2009 H1N1) in separate infections as in co-infections. Post-infection oral gavage of acid-stable TG protected mice against a lethal influenza virus challenge. Together with its ability to inhibit the different viruses before or during active infection, and with an antiviral duration of at least 48 h post-TG exposure, we propose that TG (or its derivatives) is a promising broad-spectrum inhibitor against SARS-CoV-2, OC43, RSV and influenza virus. 相似文献