54 research outputs found
Quantum Interference Effects in Slowly Rotating NUT Space-time
General relativistic quantum interference effects in the slowly rotating NUT
space-time as the Sagnac effect and the phase shift effect of interfering
particle in neutron interferometer are considered. It was found that in the
case of the Sagnac effect the influence of NUT parameter is becoming important
due to the fact that the angular velocity of the locally non rotating observer
must be larger than one in the Kerr space-time. In the case of neutron
interferometry it is found that due to the presence of NUT-parameter an
additional term in the phase shift of interfering particle emerges. This term
can be, in principle, detected by sensitive interferometer and derived results
can be further used in experiments to detect the gravitomagnetic charge.
Finally, as an example, we apply the obtained results to the calculation of the
UCN (ultra-cold neutrons) energy level modification in the slowly rotating NUT
space-time.Comment: 11 pages, 1 figure, accepted for publication in Int. J. Mod. Phys. D;
added reference
Specific features of the luminescence and conductivity of zinc selenide on exposure to X-ray and optical excitation
The set of experimental data on the X-ray-excited luminescence and X-ray
induced conductivity of ZnSe are compared to the data on the photoluminescence
and photoconductivity. It is experimentally established that the
current-voltage characteristics and the kinetics of phosphorescence and current
relaxation depend on the type of excitation. It is found that the external
electric field influences the intensity and shape of bands in the luminescence
spectra. It is shown that the character of excitation defines the kinetics of
recombination, charge carrier trapping, and conductivity in wide-gap
semiconductors.Comment: 7 pages, 7 figures, published in Fizika i Tekhnika Poluprovodnikov,
2010, Vol. 44, No. 5, pp. 594-59
Development of a stable eukaryotic strain producing fully human monoclonal antibody on the basis of the human antibody against ectromelia virus
Fullyhuman antibodies have a great therapeutic importance; however, the development of stable strains providing a high level of production of fullsize antibodies is a challenging task, as antibody molecules contain two types of polypeptide chains. To develop the producing strain, random integration of the plasmid containing the gene encoding the target protein into the genome of the host cells is commonly used. The aim of this study was the development of an original expression system, using gene targeting to integrate the gene encoding the fullyhuman antibody into the transcriptionally active region of the genome of eukaryotic suspension cells CHOS. To develop a stable strain, the cassette vector plasmid pCDNA5/FRTDHFRCHCL containing the site of homologous recombination and the genes encoding heavy and light chains of the fully human antibody of the IgG1/kappa class was constructed at the first step. Notably, DNA of the plasmid pCDNA5/FRTDHFRCHCL was organized in such a way that the restriction sites for rapid cloning of DNA fragments encoding the variable domains of heavy and light chains were inserted upstream of the sequences encoding constant domains of the heavy and light chains of the antibody. Secondly, DNA fragments encoding the variable domains of the heavy and light chains of antibody against orthopoxvirus protein p35 were inserted into the pCDNA5/FRTDHFRCHCL cassette plasmid. Then, CHOS/FRT cells, which contain the FRTsite for homologous recombination and are able to produce green fluorescence protein GFP, were transfected with the constructed plasmid. After the insertion of the target genes into the FRTsite, GFP production was supposed to stop. Using this selection system, a stable clone producing target antibody fh8E was selected with the level of production of about 100 μg/ml. The binding affinity of purified antibody fh8E with the targeted protein, measured by surface plasmon resonance, was 12 nM. In addition, antibody fh8E demonstrated antivaccinia virus activity in the plaque reduction neutralization test in vitro
Исследование эффективности лечения больных хронической обструктивной болезнью легких препаратом Спирива (тиотропия бромид) в Новосибирской области
A regional branch programme "Improvement of quality of life of COPD patients" had been developed and adopted at Novosibirsk region. Its content is financial support and organization of COPD treatment using thiotropium bromide. The study involved 35 COPD patients, 31of them (28 males and 3 females) completed the treatment. The average age of participants was 53.2 ± 3.9 yrs. We assessed severity of clinical signs using a 3-point scale; spirometry parameters, physical tolerability in 6-minute walk test. We also calculated cost of therapy of COPD patients. The follow-up duration was 6 months. Results demonstrated a significant reduction in clinical severity of COPD, improvement in functional capacity during the treatment with Spiriva. The rate of seeking for aid, number of seek days and length of staying in a hospitals decreased. Medical expenses for COPD treatment increased when used Spiriva due to its high cost but with regards to a total expenditure (direct and indirect) the cost-efficacy was 32.7 %.В Новосибирской области разработана и принята областная отраслевая программа "Повышение качества жизни больных ХОБЛ", содержание которой заключалось в финансировании и организации мероприятий по лечению ХОБЛ препаратом тиотропия бромид. В исследовании участвовали 35 больных ХОБЛ, из которых завершили лечение 31 человек (28 мужчин и 3 женщины). Средний возраст участников составил 53,2 ± 3,9 лет. Оценивали выраженность симптомов заболевания по 3-балльной шкале, показатели спирометрии, толерантность к физической нагрузке — в 6-минутном тесте, рассчитывали затраты на лечение больных ХОБЛ. Длительность наблюдения составила 6 мес. Результаты исследования показали, что лечение препаратом Спирива ведет к достоверному уменьшению выраженности клинических симптомов ХОБЛ, повышению толерантности к физической нагрузке в течение всего курса терапии. За время лечения у больных достоверно снизились частота обращений за медицинской помощью, длительность периодов временной нетрудоспособности и стационарного лечения. Медицинские затраты на лечение ХОБЛ при использовании Спиривы возрастают за счет его стоимости, но при учете всех затрат (прямых и косвенных) экономическая эффективность составила 32,7 %
Гипоксические белки VEGF A и CA IX и резистентность клеток сарком мягких тканей к химиопрепаратам: пилотный опыт ex vivo анализа
Introduction. The identification of predictive factors is a cornerstone task of modern oncology. The development of new targeted drugs determines the need for prediction of chemosensitivity of each patient to the prescribed therapy, in this regard, the search for biomarkers of predictive response to therapy is actively conducted.The study objective to investigate the relationship between tumor cell resistance and the expression levels of CA IX (carbonic anhydrase IX) and VEGF A (vascular endothelial growth factor А) in patient-derived cultures of soft tissue sarcomas.Materials and methods: ex vivo soft tissue sarcoma cell culture, resazurin test, immunoblotting.Results. We obtained 46 ex vivo samples of soft tissue sarcoma cultures for which chemosensitivity to doxorubicin, ifosfamide, docetaxel, gemcitabine, and their combinations was assessed by the resazurin cytotoxicity test. We analyzed the relationship between the expression of hypoxic proteins VEGF A and CA IX and the resistance to drugs. A correlation between the CA IX expression in hypoxia and cell resistance to ifosfamide and its combination with doxorubicin was found. Soft tissue sarcomas with high VEGF A index were resistant to doxorubicin, docetaxel, and its combination with gemcitabine (p <0.05).Conclusion. The data obtained on patient-derived cultures indicate the relationship between hypoxic signaling and resistance of soft tissue sarcomas to chemotherapeutics.Введение. Поиск предиктивных факторов является краеугольной задачей современной онкологии. Разработка большого числа новых таргетных препаратов определяет необходимость четкого предсказания хемочувствительности конкретного пациента к назначаемой терапии. В связи с этим активно ведется поиск биомаркеров прогноза ответа на терапию.Цель исследования – изучение взаимосвязи между резистентностью опухолевых клеток и уровнем экспрессии CA IX (карбоангидразы IX) и VEGF A (фактора роста эндотелия сосудов А) в ex vivo культурах сарком мягких тканей.Материалы и методы. В исследование были включены ex vivo культуры сарком мягких тканей, использованы резазуриновый тест, иммуноблоттинг.Результаты. Получено 46 ex vivo образцов культур сарком мягких тканей, для которых с помощью резазуринового теста на цитотоксичность определена хемочувствительность к доксорубицину, ифосфамиду, доцетакселу, гемцитабину и их комбинациям. Проведен анализ связи экспрессии гипоксических белков VEGF A и CA IX с резистентностью к химиопрепаратам. Обнаружена корреляция уровня экспрессии CA IX в гипоксии с резистентностью клеток к ифосфамиду и его комбинации с доксорубицином. Образцы сарком мягких тканей, обладающие высоким индексом VEGF A, были резистентны к доксорубицину, доцетакселу и его комбинации с гемцитабином (p <0,05).Заключение. Полученные на ex vivo культурах данные свидетельствуют о взаимосвязи гипоксического сигналинга и резистентности сарком мягких тканей к химиотерапии
Multiband variability studies and novel broadband SED modeling of Mrk 501 in 2009
Aims. We present an extensive study of the BL Lac object Mrk 501 based on a data set collected during the multi-instrument campaign spanning from 2009 March 15 to 2009 August 1, which includes, among other instruments, MAGIC, VERITAS, Whipple 10 m, and Fermi-LAT to cover the gamma-ray range from 0.1 GeV to 20 TeV; RXTE and Swift to cover wavelengths from UV to hard X-rays; and GASP-WEBT, which provides coverage of radio and optical wavelengths. Optical polarization measurements were provided for a fraction of the campaign by the Steward and St. Petersburg observatories. We evaluate the variability of the source and interband correlations, the gamma-ray flaring activity occurring in May 2009, and interpret the results within two synchrotron self-Compton (SSC) scenarios.Methods. The multiband variability observed during the full campaign is addressed in terms of the fractional variability, and the possible correlations are studied by calculating the discrete correlation function for each pair of energy bands where the significance was evaluated with dedicated Monte Carlo simulations. The space of SSC model parameters is probed following a dedicated grid-scan strategy, allowing for a wide range of models to be tested and offering a study of the degeneracy of model-to-data agreement in the individual model parameters, hence providing a less biased interpretation than the "single-curve SSC model adjustment" typically reported in the literature.Results. We find an increase in the fractional variability with energy, while no significant interband correlations of flux changes are found on the basis of the acquired data set. The SSC model grid-scan shows that the flaring activity around May 22 cannot be modeled adequately with a one-zone SSC scenario (using an electron energy distribution with two breaks), while it can be suitably described within a two (independent) zone SSC scenario. Here, one zone is responsible for the quiescent emission from the averaged 4.5-month observing period, while the other one, which is spatially separated from the first, dominates the flaring emission occurring at X-rays and very-high-energy (> 100 GeV, VHE) gamma-rays. The flaring activity from May 1, which coincides with a rotation of the electric vector polarization angle (EVPA), cannot be satisfactorily reproduced by either a one-zone or a two-independent-zone SSC model, yet this is partially affected by the lack of strictly simultaneous observations and the presence of large flux changes on sub-hour timescales (detected at VHE gamma rays).Conclusions. The higher variability in the VHE emission and lack of correlation with the X-ray emission indicate that, at least during the 4.5-month observing campaign in 2009, the highest energy (and most variable) electrons that are responsible for the VHE gamma rays do not make a dominant contribution to the similar to 1 keV emission. Alternatively, there could be a very variable component contributing to the VHE gamma-ray emission in addition to that coming from the SSC scenario. The studies with our dedicated SSC grid-scan show that there is some degeneracy in both the one-zone and the two-zone SSC scenarios probed, with several combinations of model parameters yielding a similar model-to-data agreement, and some parameters better constrained than others. The observed gamma-ray flaring activity, with the EVPA rotation coincident with the first gamma-ray flare, resembles those reported previously for low frequency peaked blazars, hence suggesting that there are many similarities in the flaring mechanisms of blazars with different jet properties
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