98 research outputs found
Methods and Technologies of Cholera Vibrio Cultivation (Scientific Review)
Displayed is the review of domestic and foreign literature sources devoted to matters of cholera vibrio cultivation. Discussed is the information concerning the following methods utilized in the technological process of vibrio growth stimulation: batch cultivation, fed-batch, fermentation and dialysis, periodic and continuous cultivation. Analyzed is the impact of such parameters as dissolved oxygen concentration, count of carbon nutrition source, medium pH, temperature rate , concentration and physiological condition of inoculate, duration of technological process, affecting the growth of this microorganism and synthesis of its antigens. Consequently, literature data analysis has contributed to the selection of proper method for cholera vibrio cultivation and consideration of the factors mentioned above for the development of manufacture technology applied to the production of medical immunoglobulin preparations for diagnostics and prophylaxis of cholera
Spin physics with antiprotons
New possibilities arising from the availability at GSI of antiproton beams,
possibly polarised, are discussed. The investigation of the nucleon structure
can be boosted by accessing in Drell-Yan processes experimental asymmetries
related to cross-sections in which the parton distribution functions (PDF) only
appear, without any contribution from fragmentation functions; such processes
are not affected by the chiral suppression of the transversity function
. Spin asymmetries in hyperon production and Single Spin Asymmetries
are discussed as well, together with further items like electric and magnetic
nucleonic form factors and open charm production. Counting rates estimations
are provided for each physical case. The sketch of a possible experimental
apparatus is proposed.Comment: Presented for the proceedings of ASI "Spin and Symmetry", Prague,
July 5-10, 2004, to be published in Czech. J. Phys. 55 (2005
Improvement of Technology of Cholera Toxin B-Subunit Production
Consideration is given to implementation of state-of-the-art filtration technologies for up-scaled manufacturing of cholera toxin B-subunit, produced by recombinant Vibrio cholerae non O1 KM93 strain. Selected are micro- and ultra-filtration membranes to be incorporated into manufacturing method. Investigated are the properties of cholera toxin B-subunit, obtained applying the pilot technology. The engineered method for up-scaled manufacturing of cholera toxin B-subunit makes the procedure easier-to-maintain due to tangential micro- and ultra-filtration, performed at the stage of purification and concentration. It excludes labor-consuming chromatographic purification, while retaining B-subunit properties. The studies undertaken make it possible to manufacture cholera toxin B-subunit with the same characteristics as in the case of the pilot technology, but under production conditions, and use it as a component for chemical cholera vaccine
Two years of experience in hospital surveillance for the severe influenza like illnesses in St. Petersburg: etiology, clinical characterization of diseases, antigenic and genetic properties of isolated influenza viruses
In this paper, we analyze the etiology of the diseases occurring during two consecutive influenza epidemic seasons in St. Petersburg, Russian Federation. The analysis is based on the results of the PCR diagnostics of the clinical samples collected from patients hospitalized in three St. Petersburg hospitals with influenza like illnesses (ILI). It was shown that the influenza virus A(H1N1)pdm09 was the dominant causative agent during the 2012-2013 epidemic season while, in the 2013-2014 season, A(H3N2) virus was predominant among adults and children. The influenza B virus activity was high in the 2012-2013 season and low in the 2013-2014 season. During both seasons, the main causative agent for the hospitalization of young children was respiratory syncytial virus (RSV), followed by rhinovirus and influenza virus. The rate of involvement of parainfluenza, adenovirus, metapneumovirus and coronavirus was low and was negligible for bocavirus. Children 0-2 and 3-6 years old formed the group of patients that was affected by acute respiratory infection agents the most. Children younger than 3 months old were the major group of the intensive care unit (ICUs) patients and only 27.5% of them were adults. RSV and rhinovirus were the leading cause of ILI among the children admitted to ICU. Among the adult patients admitted to the ICU, only influenza A(H1N1)pdm09, A(H3N2) and B viruses were detected during both influenza seasons.According to the results of the antigenic and genetic analysis, most influenza A(H1N1)pdm09 and A(H3N2) viruses circulating in St. Petersburg matched the vaccine strains recommended by the WHO for vaccine composition in the 2012-2013 and 2013-2014 seasons.In this paper, we analyze the etiology of the diseases occurring during two consecutive influenza epidemic seasons in St. Petersburg, Russian Federation. The analysis is based on the results of the PCR diagnostics of the clinical samples collected from patients hospitalized in three St. Petersburg hospitals with influenza like illnesses (ILI). It was shown that the influenza virus A(H1N1)pdm09 was the dominant causative agent during the 2012-2013 epidemic season while, in the 2013-2014 season, A(H3N2) virus was predominant among adults and children. The influenza B virus activity was high in the 2012-2013 season and low in the 2013-2014 season. During both seasons, the main causative agent for the hospitalization of young children was respiratory syncytial virus (RSV), followed by rhinovirus and influenza virus. The rate of involvement of parainfluenza, adenovirus, metapneumovirus and coronavirus was low and was negligible for bocavirus. Children 0-2 and 3-6 years old formed the group of patients that was affected by acute respiratory infection agents the most. Children younger than 3 months old were the major group of the intensive care unit (ICUs) patients and only 27.5% of them were adults. RSV and rhinovirus were the leading cause of ILI among the children admitted to ICU. Among the adult patients admitted to the ICU, only influenza A(H1N1)pdm09, A(H3N2) and B viruses were detected during both influenza seasons. According to the results of the antigenic and genetic analysis, most influenza A(H1N1)pdm09 and A(H3N2) viruses circulating in St. Petersburg matched the vaccine strains recommended by the WHO for vaccine composition in the 2012-2013 and 2013-2014 seasons
Hardware-Controlled Method of Desalting Antigen Components of Cholera Chemical Vaccine
Experimentally substantiated is the possibility to apply tangential ultrafiltration for desalting antigen components of the tableted bivalent chemical cholera vaccine. Specified are the technological parameters of the process. It is demonstrated that the properties of choleragen-anatoxin (produced by Vibrio cholerae strain 569B Inaba) and O-antigens (produced from V. cholerae 569B Inaba and M-41 Ogawa strains) obtained using the designed methodology are as efficient as the ones manufactured using certified procedure and satisfy regulatory requirements. Experimentally substantiated technology for the desalting of antigen components of chemical cholera vaccine provides for the reduction of the time elapsed up to 5-6 hours from the original 3 to 4 days. It also allows for the manufacturing under controlled conditions. This hard-ware controlled method of desalting has been implemented into the vaccine production practice
Magnetic fileds of coalescing neutron stars and the luminosity function of short gamma-ray burst
Coalescing neutron star binaries are believed to be the most reliable sources
for ground-based detectors of gravitational waves and likely progenitors of
short gamma-ray bursts. In the process of coalescence, magnetic fields of
neutron stars can induce interesting observational manifestations and affect
the form of gravitational wave signal. In this papaer we use the population
synthesis method to model the expected distribution of neutron star magnetic
fields during the coalescence under different assumptions on the initial
parameters of neutron stars and their magnetic field evolution. We discuss
possible elecotrmagnetic phenomena preceding the coalescence of magnetized
neutron star binaries and the effect of magnetic field on the gravitational
wave signal. We find that a log-normal (Gaussian in logarithms) distribution of
the initial magnetic fields of neutron stars, which agrees with observed
properties of radio pulsars, produces the distribution of the magnetic field
energy during the coalescence that adequately describes the observed luminosity
function of short gamma-ray bursts under different assumptions on the field
evolution and initial parameters of neutron stars. This agreement lends further
support to the model of coalescing neutron star binaries as progenitors of
gamma-ray bursts.Comment: v.2, LATEX, 25 pages, inc. 7 ps figures, Astron. Lett., in press.
Typos corrected, reference adde
Properties of Experimental and Standard Preparations of the Protective O Antigen of <I>Vibrio cholerae</I> M41 Ogawa
Investigated are immunochemical, chemical and biochemical properties of the O-antigen preparations obtained from
Vibrio cholerae M41 classical biovar, serotype Ogawa strain using standard manufacturing and improved technologies of their concentrating. The preparations have been concentrated by ultrafiltration in the mode of tangential liquid flow with membranes of various cut-off levels for a particular molar weight. ELISA has revealed equal O-antigen load in all of these preparations. Studies of specific fractures by means of chromatographic and electrophoretic methods have demonstrated their properties to be alike. Chemical composition analysis has also identified coincidence in the load of components under specification. Thus, it has been proved that application of the improved
V. cholerae protective antigen concentrating technology for manufacturing cholera chemical bivalent palletized vaccine is justified
EVALUATION OF VIBRIO CHOLERAE 569B INABA PROTECTIVE ANTIGENES, DERIVED ON INDUSTRIAL AND DEVELOPED BIOREACTORS AS WELL AS BY IMPROVED TECHNOLOGY
We evaluated immunochemical, physical and biochemical properties of Vibrio cholerae 569B INABA protective antigenes, derived on industrial and own-developed bioreactors as well as by technology of its concentration by tangential ultrafiltration. We detected, protease, twinase and. lysophospholipase in all samples. Also, dotimmunoanalysis showed equal concentration, of cholerogen-anatoxine and. O-antigen in all samples too. Using chromatography and. electrophoresis, we found their properties as similar. Thus, we suppose to be possible using developed bioreactor as well as technology of Vibrio cholerae 569B INABA protective antigens concentration by tangential concentration during a process of synthetic oral cholera vaccine production
Measurement of the Longitudinal Spin Transfer to Lambda and Anti-Lambda Hyperons in Polarised Muon DIS
The longitudinal polarisation transfer from muons to lambda and anti-lambda
hyperons, D_LL, has been studied in deep inelastic scattering off an
unpolarised isoscalar target at the COMPASS experiment at CERN. The spin
transfers to lambda and anti-lambda produced in the current fragmentation
region exhibit different behaviours as a function of x and xF . The measured x
and xF dependences of D^lambda_LL are compatible with zero, while
D^anti-lambda_LL tends to increase with xF, reaching values of 0.4 - 0.5. The
resulting average values are D^lambda_LL = -0.012 +- 0.047 +- 0.024 and
D^anti-lambda_LL = 0.249 +- 0.056 +- 0.049. These results are discussed in the
frame of recent model calculations.Comment: 13 pages, 7 figure
A fully covariant mean-field dynamo closure for numerical 3+1 resistive GRMHD
The powerful high-energy phenomena typically encountered in astrophysics
invariably involve physical engines, like neutron stars and black hole
accretion disks, characterized by a combination of highly magnetized plasmas,
strong gravitational fields, and relativistic motions. In recent years
numerical schemes for General Relativistic MHD (GRMHD) have been developed to
model the multidimensional dynamics of such systems, including the possibility
of an evolving spacetime. Such schemes have been also extended beyond the ideal
limit including the effects of resistivity, in an attempt to model dissipative
physical processes acting on small scales (sub-grid effects) over the global
dynamics. Along the same lines, magnetic fields could be amplified by the
presence of turbulent dynamo processes, as often invoked to explain the high
values of magnetization required in accretion disks and neutron stars. Here we
present, for the first time, a further extension to include the possibility of
a mean-field dynamo action within the framework of numerical 3+1 (resistive)
GRMHD. A fully covariant dynamo closure is proposed, in analogy with the
classical theory, assuming a simple alpha-effect in the comoving frame. Its
implementation into a finite-difference scheme for GRMHD in dynamical
spacetimes [the X-ECHO code: (Bucciantini and Del Zanna 2011)] is described,
and a set of numerical test is presented and compared with analytical solutions
wherever possible.Comment: 16 pages, 11 figures, accepted for publication in MNRA
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