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1.
Braz J Biol ; 84: e282174, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38836803

RESUMO

The elemental status of cattle is one of the important factors, which determine its growth, fertility, fetal development, meat and dairy production, etc. Therefore, the study of content of different elements in cattle organs and tissues and its correlation with cattle characteristics and diet is urgent task. It is also important to develop intravital and low-invasive methods to analyze element content in cattle to regulate its diet during lifetime. In the present work, we have studied the content and distribution of manganese in Hereford cattle from an ecologically clean zone of Western Siberia (Russia). 252 samples were taken from 31 bulls aged 15-18 months. They were collected from various livestock farms in the region and analyzed using atomic absorption spectrophotometry (organs and muscle tissue) and inductively coupled plasma atomic emission spectrometry (hair). The median values of manganese concentration obtained in natural moisture for hair, heart, kidneys, liver, lungs, muscles, spleen, testes, and brain were 25, 0.37, 1.0, 2.6, 0.4, 0.2, 0.4, 0.5, and 0.5 ppm. Accordingly, the concentration of manganese differs significantly in the organs and tissues of animals (H = 188.6, df = 8, p <0.0001). Statistically significant associations of manganese were revealed in pairs: liver-testis, hair-testis, spleen-testis, and heart-brain. The classification of organs and tissues of animals according to the level of content and variability of manganese is carried out. The concentration of manganese in the body is not uniform, most of all it is deposited in the hair and excretory organs of the liver and kidneys. In other organs and muscle tissues, the distribution of manganese is more even and is in the range of 0.2-0.5 ppm. The resulting ranges can be used as a guideline for Hereford cattle bred in Western Siberia.


Assuntos
Manganês , Espectrofotometria Atômica , Animais , Manganês/análise , Bovinos , Masculino , Sibéria , Cabelo/química , Distribuição Tecidual
2.
Kardiologiia ; 60(4): 70-76, 2020 Mar 27.
Artigo em Russo | MEDLINE | ID: mdl-32394860

RESUMO

Aim To develop a method for prediction of high-grade ventricular extrasystole (VE) in patients with chronic heart failure with preserved ejection fraction (CHF-PEF) based on results of an echocardiography (EchoCG) study.Material and methods At the first step, the study included 121 patients of the Cardiology Department, Municipal Clinical Hospital #31, St. Petersburg (calculation group) with symptoms and clinical signs of CHF-PEF (median age, 62 years). For testing accuracy of the developed formula, a control group was formed, which consisted of 42 patients with CHF-PEF (median age, 59 years). EchoCG at rest and ECG Holter monitoring were performed for all patient. The VE classification according to B. Lown and M. Wolf (1971) in the M. Ryan (1975) modification was used. Results of the evaluation were determined by the most significant recorded grade. Grade III or higher VE were considered as high-grade VE.Results Using logistic regression analysis of data for patients of the calculation group, a statistical model was constructed and a respective formula was developed to predict a probability of high-grade VE in CHF-PEF patients depending on the presence of risk factors (EchoCG criteria). According to the obtained data the following factors primarily contributed to the model: interventricular septal (IVS) thickness (p=0.007; Wald=7.44), end-diastolic volume index (EDVI) (p=0.044; Wald=4.13), and the degree of diastolic dysfunction (DD) (p<0.0001; Wald=19.90). For testing the formula accuracy, the analysis was performed in the control group. Based on data of both stages, the following values were obtained: for the calculation group, the method sensitivity was 77.8 %, the specificity was 82.4 %, the accuracy was 81.0 %; for the control group, 81.8 %, 70 %, and 76.2 %, respectively; for both groups together, 79.3 %, 80.0 %, and 79.8 %, respectively. In ROC-analysis of this prognostic model, the area under the ROC-curve (AUC) was 0.852 (95 % CI: 0.776-0.910; p<0.0001) for the calculation group; 0.818 (95 % CI: 0.669-0.920; p<0.0001) for the control group; and 0.855 (95 % CI: 0.792-0.905; p<0.0001) for both groups together, which indicated a good quality of the prognostic model.Conclusion The EchoCG predictors of high-grade VE in patients with CHF-PEF included degree of DD, EDVI, and IVS thickness. The developed method with the constructed formula for prediction of high-grade VE in CHF-PEF patients showed high sensitivity, specificity and accuracy.


Assuntos
Insuficiência Cardíaca , Complexos Ventriculares Prematuros , Ecocardiografia , Humanos , Pessoa de Meia-Idade , Curva ROC , Volume Sistólico
3.
J Steroid Biochem Mol Biol ; 169: 176-188, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27163393

RESUMO

Stored platelet concentrates (PLCs) for therapeutic purpose, develop a platelet storage lesion (PSL), characterized by impaired platelet (PLT) viability and function, platelet extracellular vesicle (PL-EV) release and profound lipidomic changes. Whereas oxidized low-density lipoprotein (oxLDL) activates PLTs and promotes atherosclerosis, effects linked to oxidized high-density lipoprotein (oxHDL) are poorly characterized. PLCs from blood donors were treated with native (nHDL) or mildly oxidized HDL (moxHDL) for 5days under blood banking conditions. Flow cytometry, nanoparticle tracking analysis (NTA), aggregometry, immunoblot analysis and mass spectrometry were carried out to analyze PL-EV and platelet exosomes (PL-EX) release, PLT aggregation, protein expression, and PLT and plasma lipid composition. In comparison to total nHDL, moxHDL significantly decreased PL-EV release by -36% after 5days of PLT storage and partially reversed agonist-induced PLT aggregation. PL-EV release positively correlated with PLT aggregation. MoxHDL improved PLT membrane lipid homeostasis through enhanced uptake of lysophospholipids and their remodeling to corresponding phospholipid species. This also appeared for sphingomyelin (SM) and d18:0/d18:1 sphingosine-1-phosphate (S1P) at the expense of ceramide (Cer) and hexosylceramide (HexCer) leading to reduced Cer/S1P ratio as PLT-viability indicator. This membrane remodeling was associated with increased content of CD36 and maturation of scavenger receptor-B1 (SR-B1) protein in secreted PL-EVs. MoxHDL, more potently than nHDL, improves PLT-membrane lipid homeostasis, partially antagonizes PL-EV release and agonist-induced PLT aggregation. Altogether, this may be the result of more efficient phospho- and sphingolipid remodeling mediated by CD36 and SR-B1 in the absence of ABCA1 on PLTs. As in vitro supplement in PLCs, moxHDL has the potential to improve PLC quality and to prolong storage.


Assuntos
Plaquetas/citologia , Coagulantes/química , Lipoproteínas HDL/química , Agregação Plaquetária , Plaquetas/metabolismo , Citometria de Fluxo , Homeostase , Humanos , Lipídeos/química , Lipoproteínas LDL/química , Lisofosfolipídeos/química , Espectrometria de Massas , Nanopartículas/química , Oxirredução , Oxigênio/química , Esfingosina/análogos & derivados , Esfingosina/química
4.
Acta Naturae ; 8(4): 60-69, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28050267

RESUMO

Many cellular processes are associated with membrane remodeling. The BAR domain protein family plays a key role in the formation and detection of local membrane curvatures and in attracting other proteins, including the regulators of actin dynamics. Based on their structural and phylogenetic properties, BAR domains are divided into several groups which affect membrane in various ways and perform different functions in cells. However, recent studies have uncovered evidence of functional differences even within the same group. This review discusses the principles underlying the interactions of different groups of BAR domains, and their individual representatives ,with membranes.

5.
Ter Arkh ; 86(11): 66-9, 2014.
Artigo em Russo | MEDLINE | ID: mdl-25715490

RESUMO

AIM: To evaluate the practical efficiency of the diagnostic algorithms for enterohemorrhagic escherichiasis, which are laid down by the current normative documents of the Russian Federation. SUBJECTS AND METHODS: The investigators estimated the prevalence of enterohemorrhagic Escherichia coli (EHEC) infection in children with the symptoms of acute enteric infections (AEI) (archival samples) and in those aged less than 5 years with fatal evolution and a history of diarrhea and hemolytic uremic syndrome (HUS), evaluated the efficiency of bacteriological tests in HUS patients with acute EHEC infection, and comparatively analyzed the documents regulating EHEC surveillance in the Russian Federation and other countries. RESULTS: Nucleic acid amplification assay showed that the prevalence of EHEC among the hospitalized children was 1.2% (27/1269), the anamnestic registration rate for HUS among the children with fatal outcomes in AEI was 20% (5/25). The efficiency of the bacteriological diagnosis of enterohemorrhagic escherichiasis in the archival samples corresponding to the early stages of the disease in the presence of diarrhea and at the HUS development stage was 48.1% (13/27) and 6.1% (2/33), respectively. There was a potential to enhance the efficiency of the normative documents regulating the etiological diagnosis of EHEC infection in the Russian Federation. CONCLUSION: The given data substantiate the necessity of including the etiological diagnosis of EHEC infection in the list of mandatory screening studies in children with sporadic cases of hemocolitis at the early stages of the disease.


Assuntos
Diarreia/microbiologia , Escherichia coli Êntero-Hemorrágica/isolamento & purificação , Infecções por Escherichia coli/diagnóstico , Síndrome Hemolítico-Urêmica/diagnóstico , Algoritmos , Técnicas Bacteriológicas , Criança , Pré-Escolar , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Síndrome Hemolítico-Urêmica/epidemiologia , Síndrome Hemolítico-Urêmica/microbiologia , Hospitalização , Humanos , Programas de Rastreamento/métodos , Técnicas de Amplificação de Ácido Nucleico , Prevalência , Federação Russa/epidemiologia
6.
Vopr Virusol ; 58(3): 32-7, 2013.
Artigo em Russo | MEDLINE | ID: mdl-24006631

RESUMO

The astroviral infections are considered among the most common pathogens of gastroenteritis in children. The incidence, molecular epidemiology and clinical manifestations of the astrovirus infection in children hospitalized with acute gastroenteritis, in various areas of the Russian Federation from 2004 to 2010 was determined.


Assuntos
Infecções por Astroviridae/epidemiologia , Gastroenterite/epidemiologia , Mamastrovirus/classificação , RNA Viral/classificação , Adolescente , Infecções por Astroviridae/complicações , Infecções por Astroviridae/virologia , Criança , Pré-Escolar , Fezes/virologia , Gastroenterite/complicações , Gastroenterite/virologia , Humanos , Incidência , Lactente , Recém-Nascido , Mamastrovirus/genética , Mamastrovirus/isolamento & purificação , Filogenia , RNA Viral/genética , Estudos Retrospectivos , Federação Russa/epidemiologia , Sorotipagem
7.
Eksp Klin Gastroenterol ; (11): 10-4, 2013.
Artigo em Russo | MEDLINE | ID: mdl-24933972

RESUMO

In 72 patients with irritable bowel syndrome (IBS) the psychological condition and electric activity of brain, serotonin level in plasma, short chain fatty acids (SFA) levels in stool were studied. In patients with IBS in aggravation of disease violations of central nerve system was observed. The increasing of reactive and personal anxious, violations in electroencephalograms and increasing serotonin level with modification of SFA levels were observed. Clinical, psychological and electroencephalographic changes, levels of serotonin and SFA is necessary to analyze for individual treatment program in patients with IBS.


Assuntos
Ácidos Graxos/sangue , Síndrome do Intestino Irritável/sangue , Serotonina/sangue , Adolescente , Adulto , Feminino , Humanos , Síndrome do Intestino Irritável/fisiopatologia , Síndrome do Intestino Irritável/terapia , Masculino , Pessoa de Meia-Idade
8.
Artigo em Russo | MEDLINE | ID: mdl-24605663

RESUMO

AIM: Determine etiologic significance of clinical strains of E. coli O145:H28 isolated from feces of a patient with hemolytic-uremic syndrome (HUS). MATERIALS AND METHODS: 20 E. coli strains isolated from feces of a patient with HUS that developed after an acute intestine infection were studied. Antigenic structure of strains was determined by sequencing of rib and fliC genes; presence of virulence genes (pap, aaf, sfa, afa, eaeA, bfpA, ial, hly, cnf, stx1, stx2, LT, ST and aer)--in PCR; ESBL production --by double disk method, ESBL genes--in PCR. RESULTS: The strains contained rfb gene coding O145, fliC gene coding H7. Genes coding synthesis of stx2-toxin and intimin (eaeA) were detected. The strains were resistant to beta-lactams due to production of CTX-M class ESBL. CONCLUSION: A causative agent E. coli O145:H28 was isolated from a patient with HUS that produces stx2-toxin and CTX-M class ESBL and has not been previously registered in Russian Federation.


Assuntos
Escherichia coli Êntero-Hemorrágica , Infecções por Escherichia coli , Síndrome Hemolítico-Urêmica , Proteínas de Bactérias/metabolismo , Criança , Escherichia coli Êntero-Hemorrágica/genética , Escherichia coli Êntero-Hemorrágica/isolamento & purificação , Infecções por Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Flagelina , Síndrome Hemolítico-Urêmica/genética , Síndrome Hemolítico-Urêmica/microbiologia , Humanos , Masculino , Federação Russa , Análise de Sequência de DNA , Fatores de Virulência/genética
9.
Nucleic Acids Res ; 34(Web Server issue): W541-5, 2006 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-16845066

RESUMO

Composite Module Analyst (CMA) is a novel software tool aiming to identify promoter-enhancer models based on the composition of transcription factor (TF) binding sites and their pairs. CMA is closely interconnected with the TRANSFAC database. In particular, CMA uses the positional weight matrix (PWM) library collected in TRANSFAC and therefore provides the possibility to search for a large variety of different TF binding sites. We model the structure of the long gene regulatory regions by a Boolean function that joins several local modules, each consisting of co-localized TF binding sites. Having as an input a set of co-regulated genes, CMA builds the promoter model and optimizes the parameters of the model automatically by applying a genetic-regression algorithm. We use a multicomponent fitness function of the algorithm which includes several statistical criteria in a weighted linear function. We show examples of successful application of CMA to a microarray data on transcription profiling of TNF-alpha stimulated primary human endothelial cells. The CMA web server is freely accessible at http://www.gene-regulation.com/pub/programs/cma/CMA.html. An advanced version of CMA is also a part of the commercial system ExPlaintrade mark (www.biobase.de) designed for causal analysis of gene expression data.


Assuntos
Algoritmos , Regiões Promotoras Genéticas , Software , Fatores de Transcrição/metabolismo , Sítios de Ligação , Células Endoteliais/metabolismo , Perfilação da Expressão Gênica , Humanos , Internet , Análise de Sequência de DNA/métodos , Interface Usuário-Computador
10.
Free Radic Biol Med ; 40(10): 1804-9, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16678018

RESUMO

Supramolecular complexes between carotenoids and a triterpene glycoside, beta-glycyrrhizic acid (GA), were found to exhibit unusual antioxidant activity. Complexation with GA increases a scavenging rate of canthaxanthin and 7',7'-dicyano-7'-apo-beta-carotene toward OOH radicals more than 10 times, but has no effect on the scavenging rate of zeaxanthin. Scavenging rate constants were measured in DMSO solution of carotenoids using the EPR spin-trapping technique. EPR parameters of spin adducts were determined as a(H) = 2.3 G, a(N) = 13.9 G for PBN (N-tert-butyl-alpha-phenylnitrone)-OOH, and a(H) = 3.4 G, a(N) = 14.9 G for the PBN-CH3 adduct. Taking into account the previously measured dependence of the scavenging rate constants toward OOH radicals on the oxidation potential of carotenoids, this result can be explained by the hypothesis that the complexation with GA affects the value of oxidation potentials. This hypothesis was confirmed by CV measurements.


Assuntos
Antioxidantes/química , Antioxidantes/metabolismo , Carotenoides/química , Carotenoides/metabolismo , Ácido Glicirretínico/química , Ácido Glicirretínico/metabolismo , Oxirredução , Detecção de Spin
11.
Bioinformatics ; 22(10): 1190-7, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16473870

RESUMO

MOTIVATION: Functionally related genes involved in the same molecular-genetic, biochemical or physiological process are often regulated coordinately. Such regulation is provided by precisely organized binding of a multiplicity of special proteins [transcription factors (TFs)] to their target sites (cis-elements) in regulatory regions of genes. Cis-element combinations provide a structural basis for the generation of unique patterns of gene expression. RESULTS: Here we present a new approach for defining promoter models based on the composition of TF binding sites and their pairs. We utilize a multicomponent fitness function for selection of the promoter model that fits best to the observed gene expression profile. We demonstrate examples of successful application of the fitness function with the help of a genetic algorithm for the analysis of functionally related or co-expressed genes as well as testing on simulated and permutated data. AVAILABILITY: The CMA program is freely available for non-commercial users. URL http://www.gene-regulation.com/pub/programs.html#CMAnalyst. It is also a part of the commercial system ExPlain (www.biobase.de) designed for causal analysis of gene expression data..


Assuntos
Algoritmos , Modelos Químicos , Análise de Sequência de Proteína/métodos , Software , Fatores de Transcrição/química , Fatores de Transcrição/genética , Sequência de Aminoácidos , Sítios de Ligação , Simulação por Computador , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , Ligação Proteica
12.
Langmuir ; 22(1): 375-84, 2006 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-16378448

RESUMO

The present study is centered on the processes involved in the photochemical generation of nanometer-sized Ag particles via illumination at 350 nm of aqueous solutions and cross linked films containing sulfonated poly(ether ether ketone) and poly(vinyl alcohol). Optical and electron paramagnetic resonance experiments, including electron nuclear double resonance data, proved conclusively that the photogenerated chromophore exhibiting a band with lambda(max) = 565 nm is an alpha-hydroxy aromatic (ketyl) radical of the polymeric ketone. This reducing species was produced by illumination of either solutions or films, but the radical lifetime extended from minutes in the fluid phase to hours in the solid. Direct evidence is presented that this long-lived chromophore reduces Ag(I), Cu(II), and Au(III) ions in solution. A rate constant of k = 1.4 x 10(3) M(-)(1) s(-)(1) was obtained for the reduction of Ag(+) by the ketyl radical from the post-irradiation formation of Ag crystallites. FTIR results confirmed that the photoprocess yielding polymeric ketyl radicals involves a reaction between the macromolecules. The photochemical oxidation of the polymeric alcohol, as well as the formation of light-absorbing macromolecular products and polyols, indicates that the sulfonated polyketone experienced transformations similar to those encountered during illumination of the benzophenone/2-propanol system.

13.
Vestn Ross Akad Med Nauk ; (3): 36-9, 2005.
Artigo em Russo | MEDLINE | ID: mdl-15852712

RESUMO

The article is dedicated to the topical problem of allergic diseases in various population groups of a large industrial region of Moscow suburb, and presents a brief review of present-day epidemiological data on allergic pathology prevalence as well as authors' own data on the morbidity of bronchial asthma, allergic dermatoses, and allergic rhinitis. The paper also contains the results of an analysis of allergic pathology dynamics within 5 to 10 years, and a retrospective analysis of allergic pathology structure in adolescents. The researchers undertook a multifactor analysis of population habitat in the town Mitishchy, based upon ecological and hygienic data concerning atmospheric air and water composition. The study points to the role played by industrial environment in the appearance of allergic skin diseases. Complex measures on allergic disease prevention are considered, and an effective pathogenically grounded method of ozonotherapy is suggested as one of prospective non-drug means of treatment.


Assuntos
Poluição Ambiental/efeitos adversos , Hipersensibilidade/epidemiologia , Adolescente , Adulto , Fatores Etários , Asma/epidemiologia , Asma/prevenção & controle , Criança , Pré-Escolar , Dermatite Atópica/epidemiologia , Dermatite Atópica/prevenção & controle , Dermatite Ocupacional/epidemiologia , Dermatite Ocupacional/prevenção & controle , Feminino , Humanos , Hipersensibilidade/prevenção & controle , Hipersensibilidade/terapia , Indústrias , Lactente , Recém-Nascido , Masculino , Moscou , Ozônio/uso terapêutico , Prevalência , Estudos Prospectivos , Estudos Retrospectivos , Rinite Alérgica Perene/epidemiologia , Rinite Alérgica Perene/prevenção & controle , Fatores de Risco
14.
J Org Chem ; 66(23): 7757-64, 2001 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-11701033

RESUMO

2-Diformylmethylene-1,3-diselenole was prepared and condensed with dithiolium phoshonium bromides and dithiolium phosphonates in the presence of base to give dendralene-type vinylogs of TTF bearing a 1,3-diselenole moiety. The electrochemistry of these dendrimers was studied. SEEPR measurements were also carried out. Calculations were carried out on the radical cations and correlated with the EPR values.

15.
Free Radic Biol Med ; 31(3): 398-404, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11461778

RESUMO

The spin trapping EPR technique was used to study the influence of carotenoids (beta-carotene, 8'-apo-beta-caroten-8'-al, canthaxanthin, and ethyl 8'-apo-beta-caroten-8'-oate) on the yield of free radicals in the Fenton reaction (Fe(2+) + H(2)O(2) --> Fe(3+) + .OH + -OH) in the organic solvents, DMSO, and methanol. DMPO and PBN were used as spin trapping agents. It was demonstrated that carotenoids could increase or decrease the total yield of free radicals depending on the oxidation potential of the carotenoids and the nature of the radicals. A reaction mechanism is suggested which includes the reduction of Fe(3+) to Fe(2+) by carotenoids. The effectiveness of this carotenoid-driven Fenton reaction increases with a decrease of the scavenging rates for free radicals and with decreasing oxidation potentials of carotenoids.


Assuntos
Antioxidantes/química , Carotenoides/química , Sequestradores de Radicais Livres/química , Peróxido de Hidrogênio/química , Ferro/química , Oxidantes/química , Cantaxantina/química , Dimetil Sulfóxido , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Radicais Livres/análise , Radical Hidroxila/análise , Cinética , Metanol , Estrutura Molecular , Solventes , Espectrofotometria , beta Caroteno/análogos & derivados , beta Caroteno/química
16.
Free Radic Biol Med ; 31(1): 43-52, 2001 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-11425489

RESUMO

The role of several natural and synthetic carotenoids as scavengers of free radicals was studied in homogeneous solutions. A set of free radicals: *OH, *OOH, and *CH(3) were generated by using the Fenton reaction in dimethyl sulfoxide. It was shown that the spin trapping technique is more informative than optical methods for the experimental conditions under study. 5,5-Dimethyl-pyrroline-N-oxide (DMPO) and N-tert-butyl-alpha-phenylnitrone (PBN) were used as spin traps for the EPR studies. The results show that the scavenging ability of the carotenoids towards radical *OOH correlates with their redox properties.


Assuntos
Antioxidantes/farmacologia , Carotenoides/farmacologia , Antioxidantes/química , Carotenoides/química , Dimetil Sulfóxido/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Sequestradores de Radicais Livres/metabolismo , Radicais Livres/metabolismo , Peróxido de Hidrogênio/química , Ferro/química , Detecção de Spin
17.
Free Radic Biol Med ; 28(7): 1030-8, 2000 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10832064

RESUMO

Free radical intermediates were detected by the electron paramagnetic resonance spin trapping technique upon protonation/deprotonation reactions of carotenoid and beta-ionone radical ions. The hyperfine coupling constants of their spin adducts obtained by spectral simulation indicate that carbon-centered radicals were trapped. The formation of these species was shown to be a result of chemical oxidation of neutral compounds by Fe(3+) or I(2) followed by deprotonation of the corresponding radical cations or addition of nucleophilic agents to them. Bulk electrolysis reduction of beta-ionone and carotenoids also leads to the formation of free radicals via protonation of the radical anions. Two different spin adducts were detected in the reaction of carotenoid polyenes with piperidine in the presence of 2-methyl-2-nitroso-propane (MNP). One is attributable to piperidine radicals (C(5)H(10)N*) trapped by MNP and the other was identified as trapped neutral carotenoid (beta-ionone) radical produced via protonation of the radical anion. Formation of these radical anions was confirmed by ultraviolet-visible spectroscopy. It was found that the ability of carotenoid radical anions/cations to produce neutral radicals via protonation/deprotonation is more pronounced for unsymmetrical carotenoids with terminal electron-withdrawing groups. This effect was confirmed by the radical cation deprotonation energy (H(D)) estimated by semiempirical calculations. The results indicate that the ability of carotenoid radical cations to deprotonate decreases in the sequence: beta-ionone > unsymmetrical carotenoids > symmetrical carotenoids. The minimum H(D) values were obtained for proton abstraction from the C(4) atom and the C(5)-methyl group of the cyclohexene ring. It was assumed that deprotonation reaction occurs preferentially at these positions.


Assuntos
Carotenoides/química , Norisoprenoides , Terpenos/química , Ânions , Cantaxantina/química , Cátions , Eletroquímica , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres/química , Piperidinas/química , Prótons , Marcadores de Spin , beta Caroteno/química
18.
Artigo em Russo | MEDLINE | ID: mdl-9825502

RESUMO

The levels of antibodies (Ab) to bacterial antigens of gram-negative enterobacteria (Reglicolipid), Streptococcus agalactiae polysaccharide, Staphylococcus aureus teichoic acid, native and denatured DNA and renal proteins in healthy pregnant women and in those with renal pathology (chronic and gestation pyelonephritis) were studied. The study revealed that the combination of an elevated levels of Ab to bacterial antigens with the elevated titers of Ab to DNA and renal proteins is indicative of acute inflammation in kidneys, and but the combination of an elevated levels of Ab bacterial antigens with the low level of Ab to DNA and renal proteins is indicative of healthy carrier state with respect to a given infective agent.


Assuntos
Anticorpos Antibacterianos/biossíntese , Antígenos de Bactérias/imunologia , Autoanticorpos/biossíntese , Autoantígenos/imunologia , Complicações Infecciosas na Gravidez/imunologia , Pielonefrite/imunologia , Doença Crônica , Feminino , Humanos , Gravidez , Staphylococcus aureus/imunologia , Streptococcus/imunologia
19.
Mikrobiol Z ; 60(1): 31-6, 1998.
Artigo em Ucraniano | MEDLINE | ID: mdl-9621686

RESUMO

Streptomycetes, which are the producers of different polyketide antibiotics, can be divided into 4 groups as to their sensitivity to landomycins A and E: 1) S. glaucescens Tü49, producer of tetracenomycin and S. aureofaciens 019, producer of chlortetracycline belong to the most landomycin-sensitive strains. 2) S. cyanogenus S136, producer of landomycin A, and S. lividans TK24, producer of actinorhodin, were sensitive to mean and high doses of landomycin E (more than 60-80 ug/ml). 3) S. globisporus 1912 (producer of landomycin E), S. cyanogenus S136, S. fradiae Tü2717, producer of urdamycins and S. coelicolor A3(2), producer of actinorhodin have moderate sensitivity to all doses of the both antibiotics but strain S136 only to low doses. 4) Resistance to landomycins A and E was observed in strain S. olivaceus Tü2353, producer of elloramycin. In all the experiments landomycin E showed the 1-2 orders higher lethal activity in comparison with landomycin A which molecule is composed of the same aglycon landomycenone A but a longer polysaccharide chain which probably hampers the penetration of antibiotic through the cell membrane.


Assuntos
Aminoglicosídeos , Antibacterianos/biossíntese , Antibacterianos/farmacologia , Streptomyces/efeitos dos fármacos , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Streptomyces/metabolismo , Relação Estrutura-Atividade
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