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1.
Arch Virol ; 164(11): 2783-2787, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31414285

ABSTRACT

Several types of Escherichia coli O-antigens form highly effective shields protecting the bacterial cell surface and preventing bacteriophages from interacting directly with their secondary (terminal) receptors. However, it is not clear if O-antigens of various types (O-serotypes) differ in their anti-phage protection efficacy. Here, we describe a new E. coli strain, F5, which has an E. coli O28ab-related O-antigen. Although the amount of O-antigen produced by this strain is comparable to that produced by other E. coli strains we tested, it appears to give the cells significantly lower protection against phage attack than other O-antigen types, such as the O-polysaccharide of E. coli F17, which we studied earlier.


Subject(s)
Bacteriophages/metabolism , Escherichia coli/metabolism , O Antigens/metabolism , Virus Attachment , Escherichia coli/classification , Escherichia coli/genetics , O Antigens/genetics
3.
Biochemistry (Mosc) ; 81(6): 600-8, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27301288

ABSTRACT

Gene clusters for biosynthesis of 24 of 34 basic O-antigen forms of Shigella spp. are identical or similar to those of the genetically closely related bacterium Escherichia coli. For 18 of these relatedness was confirmed chemically by elucidation of the O-antigen (O-polysaccharide) structures. In this work, structures of the six remaining O-antigens of E. coli O32, O53, O79, O105, O183 (all related to S. boydii serotypes), and O38 (related to S. dysenteriae type 8) were established using (1)H and (13)C NMR spectroscopy. They were found to be identical to the Shigella counterparts, except for the O32- and O38-polysaccharides, which differ in the presence of O-acetyl groups. The structure of the E. coli O105-related O-polysaccharide of S. boydii type 11 proposed earlier is revised. The contents of the O-antigen gene clusters of the related strains of E. coli and Shigella spp. and different mechanisms of O-antigen diversification in these bacteria are discussed in view of the O-polysaccharide structures established. These data illustrate the value of the O-antigen chemistry and genetics for elucidation of evolutionary relationships of bacteria.


Subject(s)
Escherichia coli/metabolism , O Antigens/chemistry , Shigella/metabolism , Carbohydrate Sequence , Carbon-13 Magnetic Resonance Spectroscopy , Lipopolysaccharides/chemistry , Lipopolysaccharides/isolation & purification , Molecular Sequence Data , Proton Magnetic Resonance Spectroscopy
4.
Klin Khir ; (5): 68-9, 2015 May.
Article in Ukrainian | MEDLINE | ID: mdl-26419041

ABSTRACT

Impact of various kinds of general anesthesia while performing transcutaneous endoscopic interventions on kidneys on postoperative occurrence and rate of nausea and vomiting were studied. Propofol and sevofluran were used for support of general anesthesia conduction. There was established, that if optimal depth of anesthesia is maintained (bispectral index 40 - 60 units), the rate of nausea and vomiting occurrence do not depend on the kind of anesthesia applied--total intravenous or the inhalation one.


Subject(s)
Anesthesia, General/methods , Kidney Calculi/surgery , Lithotripsy , Nausea/diagnosis , Postoperative Complications , Vomiting/diagnosis , Adolescent , Adult , Anesthetics, Inhalation , Anesthetics, Intravenous , Female , Humans , Kidney/pathology , Kidney/physiopathology , Kidney/surgery , Kidney Calculi/pathology , Kidney Calculi/physiopathology , Male , Methyl Ethers , Middle Aged , Nausea/physiopathology , Postoperative Period , Propofol , Sevoflurane , Vomiting/physiopathology
5.
J Chem Phys ; 128(4): 044312, 2008 Jan 28.
Article in English | MEDLINE | ID: mdl-18247954

ABSTRACT

A new spectroscopically determined potential energy surface (PES) for HD(16)O is presented. This surface is constructed by adjusting the high accuracy ab initio PES of Polyansky et al. [Science 299, 539 (2003)] by fitting to both published experimental data and our still unpublished data. This refinement used experimentally derived term values up to 25,000 cm(-1) and with J< or =8: a data set of 3478 energy levels once some levels with ambiguous assignment is excluded. To improve the extrapolation properties of the empirical PES, the restraint that the resulting PESs remain close to the ab initio surface was imposed. The new HDO_07 PES reproduces the experimental data, including high J levels not included in the fit, with a root mean square error of 0.035 cm(-1). Predictions for rotation-vibration term values up to J=12 are made.


Subject(s)
Algorithms , Deuterium Oxide/chemistry , Oxygen/chemistry , Water/chemistry , Energy Transfer , Hydrogen Bonding , Models, Theoretical , Spectrum Analysis , Thermodynamics
6.
J Mol Spectrosc ; 205(1): 1-8, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11148100

ABSTRACT

The water-vapor spectra in the near-infrared and visible region were reanalyzed with the purpose of finding experimental evidences of unusual high-order resonance between "dark" high-bending and "bright" stretch vibration states. About 70 transitions to the (050), (060), (070), (080), (160), (061), (170), (071), and, even (0 10 0) bending states, and their resonating partners were assigned in the spectra that gives the experimental energy levels lying near or above the potential energy barrier to linearity. The assignments were confirmed by combination differences and simultaneous observation of both perturbed and perturbing levels. It was found that the high-order resonances with large changing of vibration quantum numbers are typical for the water molecule and they are caused by the strong centrifugal distortion near the linear configuration. These resonances destroy the usual polyad scheme originating from well-known Coriolis, Darling-Dennison, and Fermi resonances in H(2)O molecule. Copyright 2001 Academic Press.

7.
J Mol Spectrosc ; 204(1): 94-105, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11034847

ABSTRACT

The absorption spectrum of HDO has been recorded by Intracavity Laser Absorption Spectroscopy in the 16 300-16 670 and 18 000-18 350 cm(-1) spectral regions corresponding to the weak 2nu(2) + 4nu(3) and nu(2) + 5nu(3) bands, respectively. The nu(2) + 5nu(3) band centered at 18 208.434 cm(-1) was found almost isolated and has been satisfactorily reproduced in the frame of the effective Hamiltonian model. On the other hand, the 2nu(2) + 4nu(3) band at 16 456.201 cm(-1) is strongly perturbed as the (0 2 4) bright state is involved in a complex interaction scheme including the (1 0 4), (5 0 1), (1 5 2), and (1 11 0) states. The rovibrational assignment of these interacting states was greatly helped by the high-accuracy ab initio predictions performed by D. Schwenke and H. Partridge [J. Chem. Phys. 000-000 (2000)]. They could be partly modeled by an effective Hamiltonian which has allowed the assignment and reproduction of most of the observed transitions. Copyright 2000 Academic Press.

8.
J Mol Spectrosc ; 203(1): 28-36, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10930329

ABSTRACT

The absorption spectrum of HDO has been recorded by intracavity laser absorption spectroscopy in the 16 540-17 055 cm(-1) spectral region corresponding to the 5nu(3) band centered at 16 920 cm(-1). The (0 0 5) vibrational state is found to be mostly isolated from the nearby rovibrational states. The corresponding rovibrational transitions were analyzed and fitted in the frame of the effective rotational Hamiltonian model in Pade-Borel approximants form. The spectroscopic parameters retrieved from the fitting reproduce 100 of the 109 determined energy levels with the root-mean-square deviation of 0.0072 cm(-1), close to the experimental accuracy. From the integrated relative intensities of a- and b-type transitions, the angle between the transition moment and the OH bond is estimated to be 46.4 degrees. This value is consistent with an increasing tilt of the transition dipole moment, away from the OH bond, when the OH stretching is excited. The evolution of the orientation of the transition dipole moment versus the vibrational excitation is then compared for the OH and OD overtone bands. Copyright 2000 Academic Press.

9.
J Mol Spectrosc ; 201(2): 297-309, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10814493

ABSTRACT

The HDO absorption spectrum was recorded in the 13 165-13 500 cm(-1) spectral region by intracavity laser absorption spectroscopy. The spectrum (615 lines), dominated by the 2nu(2) + 3nu(3) and nu(1) + 3nu(3) bands, was assigned and modeled leading to the derivation of 196 accurate energy levels of the (103) and (023) vibrational states. Finally, 150 of these levels were reproduced by an effective Hamiltonian involving two vibrational dark states interacting with the (023) and (103) bright states. The rms deviation achieved by variation of 28 parameters is 0.05 cm(-1), compared to an averaged experimental uncertainty of 0.007 cm(-1), indicating the limit of validity of the effective Hamiltonian approach for HDO at high-vibrational excitation. The predictions of previous ab initio calculations of the HDO spectrum (H. Partridge and D. Schwenke, J. Chem. Phys. 106, 4618-4639 (1997)) were extensively used in the assignment process. The particular spectral region under consideration was used to test and discuss the improvements of new ab initio calculations recently performed on the basis of the same potential energy surface but with an improved dipole-moment surface. The improvements concern both the energy levels and the line intensities. In particular, the strong hybrid character of the nu(1) + 3nu(3) band is very well accounted for by the new ab initio calculations. Copyright 2000 Academic Press.

10.
J Mol Spectrosc ; 199(1): 59-72, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10712871

ABSTRACT

The absorption spectrum of the HDO molecule recorded by intracavity laser absorption spectroscopy in the 14 980-15 350 cm(-1) spectral region was assigned and modeled in the frame of the effective Hamiltonian approach. The spectrum (496 lines) results, mainly, from transitions to the rotational sublevels of the (014) bright state. An important number of transitions involving the (142) and (0 12 0) highly excited bending states could be identified, borrowing their intensities through high-order resonance interactions with the (014) state. An original feature shown by the present analysis is that all the transitions involving unperturbed energy levels of the (014) state are exclusively of A type, while both A- and B-type transitions are observed when the upper states are perturbed by the resonance interactions. One hundred forty-five energy levels of the three interacting states were derived from the spectrum and fitted to the effective rotational Hamiltonian in Pade-Borel approximants form with 29 varied parameters yielding an rms deviation of 0.038 cm(-1). A few energy levels are affected by additional local resonances with perturbers which have been identified. Finally, 48 transitions of the very weak 6nu(1) band were assigned and fitted as an isolated band. Copyright 2000 Academic Press.

11.
J Mol Spectrosc ; 199(2): 158-165, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10637101

ABSTRACT

The 3nu(2) overtone band of deuterium oxide, D(2)O, centered at 3474.3193 cm(-1), has been measured with high resolution in a 4-m base-length White cell attached to a Fourier transform spectrometer. The analysis of the spectrum led to the assignment of 347 transitions in this band, defining rovibrational energy levels in the (030) state up to K(a) = 7 for J as high as 9, and lower K(a) levels for J as high as 16. The (030) state was treated as an isolated state, following a Padé-Borel approximation in the effective Hamiltonian. Of the 115 energy levels included in the analysis, 80% were reproduced by the 21 adjusted parameters to within 0.0008 cm(-1), and the largest error was 0.0017 cm(-1). Copyright 2000 Academic Press.

12.
J Mol Spectrosc ; 197(2): 122-132, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10479579

ABSTRACT

The absorption spectrum of HDO was recorded by intracavity laser absorption spectroscopy in the 13 560-14 050 cm(-1) spectral region. Among 437 lines attributed to HDO, 399 were assigned to the 4nu(3) highly excited overtone transition. One hundred twenty-nine experimental energy levels were derived from the spectrum identification with rotational quantum numbers J as high as 16 and K(a) as high as 7. The (004) vibrational state of HDO was found to be nearly isolated. Rotational and centrifugal distortion parameters of the effective rotational Hamiltonian in the Pade-Borel approximants form, retrieved from the fitting, allow the reproduction of the experimental energy levels with the root-mean-square deviation of 0.012 cm(-1), close to the experimental accuracy. Some rotational energy levels of the (004) state seem to be slightly perturbed by local resonances with the (052) highly excited bending state. The resonance mixing was found to be large enough to give rise to seven 5nu(2) + 2nu(3) transitions, but otherwise too weak to be observable. The maximum difference between the derived experimental energy levels and the recent high accuracy ab initio predictions (H. Partridge and D. W. Schwenke, J. Chem. Phys. 106, 4618-4639 (1997)) is -2.7 cm(-1). Copyright 1999 Academic Press.

13.
Gig Sanit ; (6): 33-5, 1998.
Article in Russian | MEDLINE | ID: mdl-11013742

ABSTRACT

The prevalence of cardiovascular diseases among 2840 children aged 6 to 15 years and 7000 neonates in two Orenburg districts was studied. High environmental pollution in one of the study districts promotes the high spread of cardiovascular diseases among children.


Subject(s)
Cardiovascular Diseases/epidemiology , Environmental Pollution , Adolescent , Age Factors , Child , Cohort Studies , Humans , Industry , Infant, Newborn , Risk Factors , Siberia , Urban Population
14.
J Mol Spectrosc ; 185(2): 211-21, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9398557

ABSTRACT

The water vapor linestrengths in the region of the 3nu + delta resonance polyad of interacting vibrational states (the corresponding upper states are (310), (211), (112), (013), (131), (230), (032), and (051)) have been analyzed leading to accurate dipole moment transition parameters. The effective rotational Hamiltonian constants used to calculate the vibration-rotation wavefunctions (J.-M. Flaud, C. Camy-Peyret, A. Bykov, O. Naumenko, T. Petrova, A. Scherbakov, L. Sinitsa, 1994. J. Mol. Spectrosc. 183, 300-309) take into account both strong centrifugal distortion effects and dark states presence. These effects are known to be important for the highly excited vibrational states of water-like molecules. The input data set included the line intensities measured by Toth (R. Toth, 1994. J. Mol. Spectrosc. 166, 176-183) and the line intensities of the weak bands 2nu1 + 3nu2, 3nu2 + 2nu3, and 3nu1 + nu2 derived from peak absorptions of a spectrum recorded at a pressure of 17.0 Torr and a path length of 434 m. The parameters of the effective dipole moment operator determined by least square fitting give a very satisfactory agreement with experimental values since the mean error for the 876 experimental linestrengths is only 3.9%. It is worth noticing that such an agreement could be reached only because high-order resonance couplings with dark states were explicitly taken into account. Copyright 1997 Academic Press. Copyright 1997Academic Press

15.
J Mol Spectrosc ; 183(2): 300-9, 1997 Jun.
Article in English | MEDLINE | ID: mdl-9252301

ABSTRACT

The absorption spectrum of water vapor has been recorded between 11 600 and 12 750 cm-1 with a Fourier transform spectrometer (Kitt Peak, Az) at a resolution of 0.012 cm-1 and with a path length of 434 m. The line assignment has led to the determination of 506 accurate energy levels of the (310) (211), (112), (013), (230), (131), (032), and (051) vibrational states which belong to the so-called 3nu + delta resonance polyad. The rotational energy levels obtained are on the average in agreement with those reported recently by R. Toth (J. Mol. Spectrosc. 166, 176-183 (1994)) for the strong bands, but there are differences for high J levels or weak bands levels (about 15% of all levels). The experimental rotational energy levels have been fitted using Pade-Borel approximants and a set of 104 vibrational energies and rotational, resonance, and centrifugal distortion constants for the (310), (211), (112), (013), (230), (131), (032), and (051) vibrational states have been determined.

16.
Gematol Transfuziol ; 38(6): 29-33, 1993 Jun.
Article in Russian | MEDLINE | ID: mdl-8307271

ABSTRACT

The study was made of submicroscopic changes in the cells of bone marrow and splenic microenvironment in mice developing virus-induced Rauscher leukemia. As shown by electron microscopy, ultrastructural cytochemistry and immunocytochemistry, ultrastructure of the complexes from the stromal and hemopoietic cells underwent noticeable alterations as early as the first days after the virus introduction. This suggests that bone marrow is the primary target of the virus in Rauscher leukemia. Affections of the macrophages, dendrite, interdigital and lymphoid cells of the spleen reflect their participation in the body defenses against the virus. Progressive shift of erythropoiesis from the bone marrow into the spleen is related to morphofunctional changes in the microenvironmental cells. The findings may be useful in consideration of cellular pathogenetic aspects of acute leukemia.


Subject(s)
Bone Marrow Cells , Leukemia, Experimental/pathology , Rauscher Virus/physiology , Retroviridae Infections/pathology , Spleen/cytology , Tumor Virus Infections/pathology , Animals , Cells/ultrastructure , Mice , Mice, Inbred BALB C
17.
Tsitologiia ; 32(1): 67-73, 1990.
Article in Russian | MEDLINE | ID: mdl-2375060

ABSTRACT

Mouse NK/LY lymphoma cells were modified by Con A or Vibrio cholerae neuraminidase (VCN). Severe damage of the modified cells was not revealed by either supravital staining or light microscopy. Ultrastructural signs of metabolic lowering in the Con-A-treated cells were determined. Some increase in electrophoretic mobility of Con-A-modified cells was found, along with its decrease in VCN-modified cells. The decrease in the pool of proliferating cells was determined in both the types of modification, being more evident in the Con-A-modified material. A marked tumorigenic decrease of Con-A-modified cells was fixed.


Subject(s)
Concanavalin A/pharmacology , Lymphoma/ultrastructure , Neuraminidase/pharmacology , Vibrio cholerae/enzymology , Animals , Cell Division/drug effects , Electrophoresis , Lymphoma/physiopathology , Membrane Potentials/drug effects , Mice , Mice, Inbred CBA , Neoplasm Transplantation , Tumor Cells, Cultured/drug effects , Tumor Cells, Cultured/ultrastructure
18.
Eksp Onkol ; 12(1): 25-31, 1990.
Article in Russian | MEDLINE | ID: mdl-2298139

ABSTRACT

The population of leukemic cells (beginning from the precursor cells) has been identified by electron-microscopy methods. Ultrastructural changes typical of the erythropoiesis alteration are determined. Peculiarities in the formation of a leukemic cells population in different hemopoietic organs and changes in erythroid islands (the main morphofunctional unit of erythropoiesis) are revealed. Data obtained show the significant disturbances in differentiation of erythroid cells in the virus leukoses and are very important form the further study of the leukemogenesis mechanisms.


Subject(s)
Bone Marrow/ultrastructure , Erythroblasts/ultrastructure , Erythropoiesis , Leukemia, Experimental/pathology , Animals , Leukemia, Experimental/blood , Mice , Mice, Inbred BALB C , Rauscher Virus
19.
Eksp Onkol ; 8(5): 54-8, 1986.
Article in Russian | MEDLINE | ID: mdl-2877861

ABSTRACT

The electron microscopic study of the blood cells in some patients with sporadic T-cell acute lymphoblastic leukemias has shown some ultrastructural peculiarities similar to T-cell lympholeukemia associated with HTLV virus, that is important for the further elucidation of etiology and pathogenesis of the T-cell lymphoproliferative diseases.


Subject(s)
Deltaretrovirus Infections/blood , Leukemia, Lymphoid/blood , Lymphocytes/ultrastructure , Cell Nucleus/enzymology , Cell Nucleus/ultrastructure , Child , Deltaretrovirus/ultrastructure , Histocytochemistry , Humans , Lymphocytes/enzymology , Microscopy, Electron , T-Lymphocytes
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