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1.
Article in Russian | MEDLINE | ID: mdl-38349695

ABSTRACT

The article analyzes past history, main milestones of making, research and improvement of anatoxins from works of Gaston Ramon who first proposed 100 years ago method of obtaining reliable vaccine preparation (anatoxin) on the basis of formalin neutralized diphtheria (and then tetanus) toxin (1922-1923) to nowadays scientific achievements in prevention and treatment of these infectious diseases.


Subject(s)
Cyanobacteria Toxins , Formaldehyde , Tropanes
2.
Article in English | MEDLINE | ID: mdl-37898896

ABSTRACT

In the history of science, there are great scientists who, without being physicians, wrote golden pages in the History of Medicine. Such was Louis Pasteur, founder of scientific microbiology and immunology. Such was his follower Gaston Ramon (1886-1963), French veterinarian and immunologist who created 100 years ago first anatoxin for active prevention of diphtheria and later tetanus and thus opened era of anatoxins (toxoids) - vaccines based on toxin molecule devoid of toxic properties, but preserving immunogenicity and antigenic specificity. For many centuries, diphtheria (originally known as 'croup') was incurable contagious disease, especially among children. In XIX century, it affected in France up to 30,000 people per year and killed every second infected child. In 1888, at the Pasteur Institute (Paris), Emile Roux (1853-1933) and Alexandre Yersin (1863-1943) demonstrated for first time that symptoms of diphtheria are caused not by bacteria themselves, but by deadly toxin released by them. The long-term search for method of treatment and prevention of diphtheria did not bring the desired result. It will take many years, before Gaston Ramon in 1923 will be able to neutralize diphtheria toxin by acting on it with formalin at certain temperature and thus will receive "anatoxin", mean of vaccination against diphtheria. The article analyzes stages of these studies, which proved high effectiveness of anatoxin and proceeded with widespread implementation of vaccination against diphtheria and later tetanus in short time in France and in Russia (with active participation of Pavel F. Zdrodovsky, 1890-1976). The separate section of the article is devoted to life story of Gaston Ramon and his activities in the Pasteur Institute. The scientist who opened the era of anatoxins did not become Nobel Prize winner, despite the fact that various organizations and scientists from many countries of the world have nominated him 155 times for the Nobel Prize in Physiology or Medicine in different years. He received recognition in France, his Motherland: Gaston Ramon is holder of the Grand Cross of the Order of the Legion of Honor and streets, colleges, lyceums, schools are named after him.


Subject(s)
Diphtheria , Tetanus , Vaccines , Humans , Child , Diphtheria/prevention & control , Diphtheria/history , Vaccination , France
3.
Opt Lett ; 48(17): 4460-4463, 2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37656528

ABSTRACT

In this Letter, we consider optical bound states in the continuum (BICs) in the infrared range supported by an all-dielectric metasurface in the form of subwavelength dielectric grating. We apply the random forest machine learning method to predict the frequency of the BICs as dependent on the optical and geometric parameters of the metasurface. It is found that the machine learning approach outperforms the standard least square method at the size of the dataset of ≈4000 specimens. It is shown that the random forest approach can be applied for predicting the subband in the infrared spectrum into which the BIC falls. The important feature parameters that affect the BIC wavelength are identified.

4.
Opt Express ; 28(2): 1426-1438, 2020 Jan 20.
Article in English | MEDLINE | ID: mdl-32121854

ABSTRACT

The interaction of non-monochromatic radiation with arrays comprising plasmonic and dielectric nanoparticles has been studied using the finite-difference time-domain electrodynamics method. It is shown that LiNbO3, TiO2, GaAs, Si, and Ge all-dielectric nanoparticle arrays can provide a complete selective reflection of an incident plane wave within a narrow spectral line of collective lattice resonance with a Q-factor of 103 or larger at various spectral ranges, while plasmonic refractory TiN and chemically stable Au nanoparticle arrays provide high-Q resonances with moderate reflectivity. Arrays with fixed dimensional parameters make it possible to fine-tune the position of a selected resonant spectral line by tilting the array relative to the direction of the incident radiation. These effects provide grounds for engineering novel selective tunable optical high-Q filters in a wide range of wavelengths, from visible to middle-IR.

5.
Opt Lett ; 44(23): 5743-5746, 2019 Dec 01.
Article in English | MEDLINE | ID: mdl-31774768

ABSTRACT

Collective lattice resonances (CLRs) in finite-sized $ 2D $2D arrays of dielectric nanospheres have been studied via the coupled dipole approximation. We show that even for sufficiently large arrays, up to $ 100 \times 100 $100×100 nanoparticles (NPs), electric or magnetic dipole CLRs may differ significantly from the ones calculated for infinite arrays with the same NP sizes and interparticle distances. The discrepancy is explained by the existence of a sufficiently strong cross-interaction between electric and magnetic dipoles induced at NPs in finite-sized lattices, which is ignored for infinite arrays. We support this claim numerically and propose an analytic model to estimate a spectral width of CLRs for finite-sized arrays. Given that most of the current theoretical and numerical researches on collective effects in arrays of dielectric NPs rely on modeling infinite structures, the reported findings may contribute to thoughtful and optimal design of inherently finite-sized photonic devices.

6.
Opt Express ; 24(23): 26851-26856, 2016 Nov 14.
Article in English | MEDLINE | ID: mdl-27857413

ABSTRACT

Significant suppression of resonant properties of single gold nanoparticles at the surface plasmon frequency during heating and subsequent transition to the liquid state has been demonstrated experimentally and explained for the first time. The results for plasmonic absorption of the nanoparticles have been analyzed by means of Mie theory using experimental values of the optical constants for the liquid and solid metal. The good qualitative agreement between calculated and experimental spectra support the idea that the process of melting is accompanied by an abrupt increase of the relaxation constants, which depends, beside electron-phonon coupling, on electron scattering at a rising number of lattice defects in a particle upon growth of its temperature, and subsequent melting as a major cause for the observed plasmonic suppression. It is emphasized that observed effect is fully reversible and may underlie nonlinear optical responses of nanocolloids and composite materials containing plasmonic nanoparticles and their aggregates in conditions of local heating and in general, manifest itself in a wide range of plasmonics phenomena associated with strong heating of nanoparticles.

7.
Eksp Klin Gastroenterol ; (3): 20-3, 2016.
Article in Russian | MEDLINE | ID: mdl-27301138

ABSTRACT

The composition and technology of complex probiotic in hard gelatin capsules was developed in Perm Branch "Biomed" of "Microgen" State Company. The preparation contains three production strains: Lactobacillus plantarum 8P-A3, L. acidophilus K3W24 and Bifidobacterium bifidum 1. Laboratory and experimental (preclinical) study of the probiotic included investigation of the antagonistic activity, "acute" and "chronic" toxicity, the effect of the preparation on histology and hematology of laboratory animals. The result of these studies suggested of the probiotic had high inhibitory activity against pathogenic microflora when compared with probiotic monopreparations and had no toxic effects on laboratory animals.


Subject(s)
Antibiosis , Drug Discovery/methods , Probiotics , Administration, Oral , Animals , Capsules , Mice , Microbial Sensitivity Tests , Probiotics/administration & dosage , Probiotics/pharmacology , Probiotics/toxicity , Rats , Toxicity Tests, Acute , Toxicity Tests, Chronic
8.
Article in Russian | MEDLINE | ID: mdl-27029116

ABSTRACT

AIM: Study safety, reactogenicity and immunologic effectiveness of a national combined vaccine against diphtheria, pertussis (acellular component), tetanus, hepatitis B and Hib-infection during immunization of volunteers aged 18-60 years. MATERIALS AND METHODS: The study was carried out in accordance with ethical standards and requirements, regulated by Helsinki declaration and Good clinical practice (ICHGCP). In a simple non-randomized clinical trial 20 adult volunteers took part, the mean age of those was 46.9 years. RESULTS: Registered: post-vaccination reactions (both local and systemic) were mild and of moderate degree of severity, stopped independently after 2-3 days without administration of drug treatment. Postvaccinal complications were not noted. Parameters of general and biochemical analysis of blood, urine, IgE content in dynamics of immunization were within normal limits. A single administration of aAPDT--HepB+Hib to individuals aged 18-60 years resulted in development of antibodies against all the components of the preparation. Seroconversion factor fluctuated from 6.9 to 53.5: CONCLUSION: The results obtained allow to recommend the vaccine for evaluation of its safety, reactogenicity, immunologic and prophylaxis effectiveness in randomized clinical observation trials in children.


Subject(s)
Antibodies, Bacterial/biosynthesis , Antibodies, Viral/biosynthesis , Diphtheria/prevention & control , Haemophilus Infections/prevention & control , Hepatitis B/prevention & control , Tetanus/prevention & control , Whooping Cough/prevention & control , Adolescent , Adult , Antibodies, Bacterial/blood , Antibodies, Viral/blood , Diphtheria/immunology , Diphtheria/microbiology , Diphtheria-Tetanus-acellular Pertussis Vaccines/administration & dosage , Diphtheria-Tetanus-acellular Pertussis Vaccines/chemistry , Diphtheria-Tetanus-acellular Pertussis Vaccines/immunology , Female , Haemophilus Infections/immunology , Haemophilus Infections/microbiology , Haemophilus Vaccines/administration & dosage , Haemophilus Vaccines/chemistry , Haemophilus Vaccines/immunology , Hepatitis B/immunology , Hepatitis B/virology , Hepatitis B Vaccines/administration & dosage , Hepatitis B Vaccines/chemistry , Hepatitis B Vaccines/immunology , Humans , Immunity, Humoral/drug effects , Male , Middle Aged , Tetanus/immunology , Tetanus/microbiology , Vaccination , Vaccines, Subunit , Whooping Cough/immunology , Whooping Cough/microbiology
9.
Article in Russian | MEDLINE | ID: mdl-15881934

ABSTRACT

The occurrence rate of HGV/GBV-C RNA, genotypic variety of isolates and various risk factors of infection with HGV/GBV-C were evaluated in 500 patients of the narcological dispensary of Novosibirsk. The occurrence rate of HGV/GBV-C RNA among all examined blood sera was 33.6%. At the same time in blood sera with HCV markers the occurrence rate of HGV/ GBV-C was 42.9% and in sera with negative results for markers HCV--25%. For gene typing of obtained isolates the direct sequencing of the amplification products of fragment NS3B and the phylogenetic analysis of the sequences thus obtained were used. Almost all isolates subjected to gene typing belonged to genotype 2, widespread in Europe, and only 1 isolate was classified with genotype 4. Statistically significant (p<0.05) risk of HGV/GBV-C infection among the examined subjects was linked with the intravenous use of drugs (OR 2.15), risky sexual behavior (OR 1.8) and the presence of virus hepatitis C (OR 2.26).


Subject(s)
Ambulatory Care , Flavivirus Infections/virology , GB virus C/genetics , Hepatitis, Viral, Human/virology , Narcotics , RNA, Viral/genetics , Substance Abuse, Intravenous/virology , Adolescent , Adult , Comorbidity , Female , Flavivirus Infections/blood , Flavivirus Infections/epidemiology , GB virus C/isolation & purification , Genotype , Hepatitis C/epidemiology , Hepatitis C/virology , Hepatitis, Viral, Human/blood , Hepatitis, Viral, Human/epidemiology , Humans , Male , Middle Aged , Molecular Sequence Data , Phylogeny , Risk Factors , Siberia/epidemiology , Substance Abuse, Intravenous/blood , Substance Abuse, Intravenous/epidemiology
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