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1.
Nanotechnology ; 28(9): 095708, 2017 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-28045008

RESUMO

Further development of microelectronics requires novel or improved technological approaches for device nanofabrication and functional properties characterization. In this paper, we studied the crystal structure and magnetic properties of epitaxial Co nanostrips with the average width of 32.6, 45.3, and 62.6 nm grown on a step-bunched Si(111)5.55 × 5.55-Cu/Cu surface. Technological conditions, under which the ultra-high aspect ratio (∼104) structurally solid, straight nanostrips of hcp-Co with crystallographic axis [0001] oriented along their long side can be grown, were determined. The dependence of the coercive force on the width of the nanostrips was demonstrated. Magnetization reversal through the transverse domain-wall nucleation and propagation in a Co nanostrip was defined with an analytical approach based on the Stoner-Wohlfarth model. Using the first-order reversal curve method, we analyzed the effect of nanostrip uniformity degree on magnetic behavior and the influence of the magnetostatic interactions on the coercive force of individual nanostrips.

2.
J Mol Biol ; 278(5): 999-1014, 1998 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-9600857

RESUMO

Isothermal titration calorimetry (ITC) was used to examine the effects of monovalent salts (NaCl, NaBr, NaF and ChCl) on the binding enthalpy (DeltaHobs) for E. coli SSB tetramer binding to the single-stranded oligodeoxythymidylates, dT(pT)69 and dT(pT)34 over a wide range of salt concentrations from 10 mM to 2.0 M (25 degrees C, pH 8.1), and when possible, the binding free energy and entropy (DeltaG degrees obs, DeltaS degrees obs). At low monovalent salt concentrations (<0.1 M), the total DeltaHobs for saturating all sites on the SSB tetramer with ssDNA shows little dependence on salt concentration, but is extremely large and exothermic (DeltaHobs=-150(+/-5) kcal/mol). This is much larger than any DeltaHobs previously reported for a protein-nucleic acid interaction. However, at salt concentrations above 0.1 M, DeltaHobs is quite sensitive to NaCl and NaBr concentration, becoming less negative with increasing salt concentration (DeltaHobs=-70(+/-1)-kcal/mol in 2 M NaBr). These salt effects on DeltaHobs were mainly a function of anion type and concentration, with the largest effects observed in NaBr, and then NaCl, with little effect of [NaF]. These large effects of salt on DeltaHobs appear to be coupled to a net release of weakly bound anions (Br- and Cl-) from the SSB protein upon DNA binding. However, at lower salt concentrations (

Assuntos
Proteínas de Bactérias/metabolismo , DNA de Cadeia Simples/metabolismo , Proteínas de Ligação a DNA/metabolismo , Escherichia coli/metabolismo , Poli T/metabolismo , Sais/química , Ânions , Calorimetria , Proteínas de Ligação a DNA/química , Ligação Proteica , Cloreto de Sódio/química , Termodinâmica
3.
Mol Biol (Mosk) ; 18(6): 1583-9, 1984.
Artigo em Russo | MEDLINE | ID: mdl-6521737

RESUMO

Ion exchangers with various capacities (0.1-0.2 mg-equiv/g of dry gel) are synthesized by means of immobilization of DNA in polyacrylamide gel. Exchanges of alkali metal cations and ammonium are studied on these exchangers and selectively coefficients are determined. The following selectivity series of immobilized DNA in reference to the above-mentioned cations is stated: Li+ greater than or equal to NH4+ greater than or equal to Cs+ greater than Rb+ greater than K+ greater than or equal to Na+. The peculiar properties of Li+ and NH4+ in this series are noted and a possible explanation of this fact is offered. A supposition regarding the reduced activity of water in the polyacrylamide gel containing DNA is made.


Assuntos
Amônia , DNA , Metais Alcalinos , Animais , Fenômenos Químicos , Química , Galinhas , Técnicas In Vitro , Troca Iônica
4.
Fiziol Zh SSSR Im I M Sechenova ; 72(10): 1406-9, 1986 Oct.
Artigo em Russo | MEDLINE | ID: mdl-3781039

RESUMO

A preliminary saturation of the blood with catecholamines enhanced the ability of atria for neuronal uptake of labeled 3H-noradrenaline. Reserpine potentiated the effect. Issuing from the pattern of formation and disintegration of the agonist receptor complexes, the data obtained are interpreted as the mechanism of increasing the heart adrenoreactivity. The activating effect of catecholamines on the neuronal uptake has a certain threshold and does not depend on the duration of pre-infusion or concentration of administered catecholamines.


Assuntos
Catecolaminas/farmacologia , Coração/inervação , Miocárdio/metabolismo , Animais , Sinergismo Farmacológico , Coração/efeitos dos fármacos , Átrios do Coração , Neurônios/metabolismo , Norepinefrina/metabolismo , Ratos , Reserpina/farmacologia
5.
Fiziol Zh SSSR Im I M Sechenova ; 72(8): 1101-6, 1986 Aug.
Artigo em Russo | MEDLINE | ID: mdl-3019793

RESUMO

A positive correlation exists between the activity of neuronal uptake and the heart beta-adrenoreactivity. The amount of catecholamines in the myocardium is unrelated to this interconnection.


Assuntos
Coração/efeitos dos fármacos , Isoproterenol/farmacologia , Miocárdio/metabolismo , Norepinefrina/metabolismo , Receptores Adrenérgicos beta/efeitos dos fármacos , Absorção , Animais , Epinefrina/análise , Feminino , Masculino , Miocárdio/análise , Norepinefrina/análise , Ratos
6.
Fiziol Zh SSSR Im I M Sechenova ; 75(2): 200-4, 1989 Feb.
Artigo em Russo | MEDLINE | ID: mdl-2542103

RESUMO

Unloaded phosphatidylcholine-cholesterol liposomes enhanced the affinity of adrenoreactive system of the rat heart muscle with the ligands and altered the degree of adrenoreceptors' negative cooperativity. The radioligand analysis with 3H-dihydroalprenolol revealed that the liposomes altered kinetic properties of sarcolemma's receptors as revealed by the enhancement of affinity with the marker, decreasing of maximal specific binding and augmentation of the degree of receptors' negative cooperativity.


Assuntos
Lipossomos/farmacologia , Músculos Papilares/efeitos dos fármacos , Receptores Adrenérgicos beta/efeitos dos fármacos , Animais , Colesterol/farmacologia , Colesterol/fisiologia , Di-Hidroalprenolol/farmacocinética , Relação Dose-Resposta a Droga , Técnicas In Vitro , Contração Isométrica/efeitos dos fármacos , Lipídeos de Membrana/análise , Lipídeos de Membrana/fisiologia , Músculos Papilares/análise , Músculos Papilares/fisiologia , Fosfatidilcolinas/farmacologia , Fosfolipídeos/análise , Fosfolipídeos/fisiologia , Ensaio Radioligante , Ratos , Receptores Adrenérgicos beta/análise , Receptores Adrenérgicos beta/fisiologia , Sarcolema/análise , Sarcolema/efeitos dos fármacos , Sarcolema/fisiologia
7.
Fiziol Zh (1978) ; 36(1): 25-9, 1990.
Artigo em Russo | MEDLINE | ID: mdl-2157611

RESUMO

The pattern of changes in kinetic properties of beta-adrenoreceptor (Cd, c+ and c-) relative to anapriline adrenoblocker under conditions of muscle perfusion by catecholamines has been estimated on papillary cardiac muscles of the rat as based on the isometric voltage. A priority increase of the receptors' affinity to the blocker is determined, that may be a result of changes in microviscosity of the lipid sarcolemma bilayer.


Assuntos
Epinefrina/farmacologia , Miocárdio/metabolismo , Norepinefrina/farmacologia , Receptores Adrenérgicos beta/metabolismo , Animais , Membrana Celular/metabolismo , Epinefrina/farmacocinética , Técnicas In Vitro , Norepinefrina/farmacocinética , Ratos
8.
Khirurgiia (Mosk) ; (5): 13-8, 1991 May.
Artigo em Russo | MEDLINE | ID: mdl-2072628

RESUMO

The article analyses two matched groups of patients with generalized purulent peritonitis of 72-hour duration in the stage of polyorganic insufficiency. There were 100 patients. Application of organ-resuscitation measures in the abdominosplanchnic zone is the key moment of the surgical treatment of patients with generalized purulent peritonitis. In view of this, peritoneoenteric lavage with oxygenated energy mass of 5-10% glucose solution is indicated together with intensive infusion-transfusion, antibacterial therapy, and extracorporeal detoxification for such patients. Combination of peritoneal lavage with enteric through a distal retrograde immobilizing dehydrostatic iliostomy produces the best results.


Assuntos
Insuficiência de Múltiplos Órgãos/etiologia , Lavagem Peritoneal , Peritonite/cirurgia , Adolescente , Adulto , Idoso , Feminino , Humanos , Cuidados Intraoperatórios , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/mortalidade , Peritonite/complicações , Peritonite/mortalidade , Período Pós-Operatório , Supuração
9.
Khirurgiia (Mosk) ; (10): 49-53, 1991 Oct.
Artigo em Russo | MEDLINE | ID: mdl-1803092

RESUMO

In the period from 1980 to 1986 fifty-nine patients were treated for generalized purulent peritonitis of 72-hour duration. The traditional methods of therapy were applied--removal of the source of peritonitis and drainage of the abdominal cavity. The mortality was 62.7%. Since 1987, peritoneal lavage with enteral administration of oxygenized 5% glucose solution is used in the treatment of patients with generalized peritonitis in the stage of poly-organic insufficiency. Peritoneal-enteral lavage was applied in the management of 41 patients, 10 of them died. The mortality was 36.5%. The efficacy of the method was judged on basis of bacteriological study, electroenterography, and functional tests for the absorptive capacity of the small intestine. The results of stage peritoneal lavage and the findings of bacteriological study lead to the conclusion that it is extremely dangerous to postpone repeated cleansing of the abdominal cavity in such patients because progressive deterioration of the condition with a fatal outcome occurs in this case. Cleansing of the abdominal cavity must be accomplished during the first lavage or 24 hours later during relaparotomy and no hope should be entertained that inadequate cleansing will be compensated for during subsequent relaparotomies.


Assuntos
Infecções Bacterianas/cirurgia , Drenagem/métodos , Insuficiência de Múltiplos Órgãos/terapia , Lavagem Peritoneal/métodos , Peritonite/cirurgia , Desintoxicação por Sorção/métodos , Anti-Infecciosos/administração & dosagem , Infecções Bacterianas/complicações , Terapia Combinada , Cuidados Críticos , Glucose/administração & dosagem , Humanos , Intubação Gastrointestinal , Insuficiência de Múltiplos Órgãos/etiologia , Peritonite/complicações , Cuidados Pós-Operatórios
10.
Khirurgiia (Mosk) ; (6): 42-7, 1990 Jun.
Artigo em Russo | MEDLINE | ID: mdl-2214574

RESUMO

On the basis of the analysed results of treatment of 248 patients with abscesses, phlegmons, and purulent wounds who received vacuum therapy and 215 patients with the same diseases treated by the traditional incision-drainage-method, as well as on the grounds of additional examination findings, the authors show the mechanisms of the effect of vacuum therapy on the course of the wound process. They substantiate pathogenetically the marked therapeutic effect of this method in patients with acute purulent diseases of the soft tissues and purulent wounds.


Assuntos
Infecções Bacterianas/cirurgia , Desbridamento/métodos , Dermatopatias Infecciosas/cirurgia , Pele/microbiologia , Sucção/métodos , Infecção dos Ferimentos/cirurgia , Doença Aguda , Infecções Bacterianas/etiologia , Humanos , Dermatopatias Infecciosas/etiologia , Cicatrização , Infecção dos Ferimentos/etiologia
11.
Lik Sprava ; (2): 47-50, 1994 Feb.
Artigo em Russo | MEDLINE | ID: mdl-8073719

RESUMO

In conditions of acute hypoxia in the presence of hyperthermia drugs were shown to exhibit various degrees of protective activity. Antihypoxic action coupled with thermoprotective activity is manifested by beneficial affect on the course of the pathological process. It is quercitrol that proved to be the most effective drug; it is capable of correcting simultaneously the disturbances emerging in different links of the pathological process: effect on the processes of lipid peroxidation and metabolism of arachidonic acid as well as on the activity of enzymes belonging to the monooxigenaze system in the experiment.


Assuntos
Febre/tratamento farmacológico , Hipóxia/tratamento farmacológico , Doença Aguda , Animais , Avaliação Pré-Clínica de Medicamentos , Febre/mortalidade , Febre/patologia , Hipóxia/mortalidade , Hipóxia/patologia , Ratos , Ratos Wistar
12.
Vestn Khir Im I I Grek ; 146(4): 109-13, 1991 Apr.
Artigo em Russo | MEDLINE | ID: mdl-1661920

RESUMO

The article shows that peritoneal-enteral lavage reduced the yield of microorganisms from the suppurative focus, the reduced yield after a single lavage might be considered as a favourable prognostic sign. Results of a quantitative bacteriological analysis are thought to be an objective criterion for performing or completing the stage of the peritoneal lavage. The peritoneal-enteral lavage promotes the activation of local defensive reactions in the abdominal cavity.


Assuntos
Intestinos , Insuficiência de Múltiplos Órgãos/microbiologia , Lavagem Peritoneal , Peritonite/microbiologia , Adolescente , Adulto , Idoso , Bactérias/isolamento & purificação , Feminino , Humanos , Linfócitos/imunologia , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/imunologia , Insuficiência de Múltiplos Órgãos/terapia , Lavagem Peritoneal/métodos , Peritonite/complicações , Peritonite/imunologia , Peritonite/terapia , Irrigação Terapêutica/métodos
19.
Farmakol Toksikol ; 49(2): 86-8, 1986.
Artigo em Russo | MEDLINE | ID: mdl-3709785

RESUMO

The method for computation of the Michaelis-Menten constant and the maximum value of effect with the intermediate conversion of the data in the Lineweaver-Burk plot is described.


Assuntos
Enzimas/metabolismo , Animais , Relação Dose-Resposta a Droga , Cinética , Matemática , Métodos , Ratos , Especificidade por Substrato
20.
Proteins ; Suppl 4: 8-22, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11013397

RESUMO

Many macromolecular interactions, including protein-nucleic acid interactions, are accompanied by a substantial negative heat capacity change, the molecular origins of which have generated substantial interest. We have shown previously that temperature-dependent unstacking of the bases within oligo(dA) upon binding to the Escherichia coli SSB tetramer dominates the binding enthalpy, DeltaH(obs), and accounts for as much as a half of the observed heat capacity change, DeltaC(p). However, there is still a substantial DeltaC(p) associated with SSB binding to ssDNA, such as oligo(dT), that does not undergo substantial base stacking. In an attempt to determine the origins of this heat capacity change, we have examined by isothermal titration calorimetry (ITC) the equilibrium binding of dT(pT)(34) to SSB over a broad pH range (pH 5. 0-10.0) at 0.02 M, 0.2 M NaCl and 1 M NaCl (25 degrees C), and as a function of temperature at pH 8.1. A net protonation of the SSB protein occurs upon dT(pT)(34) binding over this entire pH range, with contributions from at least three sets of protonation sites (pK(a1) = 5.9-6.6, pK(a2) = 8.2-8.4, and pK(a3) = 10.2-10.3) and these protonation equilibria contribute substantially to the observed DeltaH and DeltaC(p) for the SSB-dT(pT)(34) interaction. The contribution of this coupled protonation ( approximately -260 to -320 cal mol(-1) K(-1)) accounts for as much as half of the total DeltaC(p). The values of the "intrinsic" DeltaC(p,0) range from -210 +/- 33 cal mol(-1) degrees K(-1) to -237 +/- 36 cal mol(-1)K(-1), independent of [NaCl]. These results indicate that the coupling of a temperature-dependent protonation equilibria to a macromolecular interaction can result in a large negative DeltaC(p), and this finding needs to be considered in interpretations of the molecular origins of heat capacity changes associated with ligand-macromolecular interactions, as well as protein folding.


Assuntos
DNA de Cadeia Simples/metabolismo , Proteínas de Ligação a DNA/metabolismo , Escherichia coli/metabolismo , Proteínas de Ligação a DNA/química , Concentração de Íons de Hidrogênio , Ligação Proteica , Prótons , Temperatura , Termodinâmica
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