RESUMEN
BACKGROUND: The novel coronavirus infection COVID-19 can be manifested by damage to the organs of the gastrointestinal tract (GIT). Damage to the gastrointestinal tract by the SARS-CoV-2 virus leads to a violation of the microbial-tissue complex of the mucous membrane of the digestive tract. A common gastroenterological manifestation of COVID-19 is diarrhea. AIM: Study of the clinical features of gastroenterological disorders and the possibility of optimizing the treatment of diarrheal syndrome in patients with COVID-19 with a mild form of viral infection. MATERIALS AND METHODS: The observation group consisted of 230 patients with mild COVID-19: K-group (n=115) with respiratory symptoms, I group (n=115) with gastrointestinal manifestations in combination and without signs of respiratory damage. In order to compare the effectiveness of treatment of diarrheal syndrome, patients of group I are randomized into 2 subgroups: Ia (n=58) prebiotic treatment (Zacofalk) and Ib (n=57) enterosorbents. RESULTS: The development of gastrointestinal symptoms with SARS-CoV-2 infection is significantly more often noted in comorbid patients (67%). Gastrointestinal symptoms were dominated by diarrhea (93.9%) and flatulence (76.5%), in 1/3 of patients they were the first manifestos of infection. It was established that in 98.4% of patients of group I (against 42.6% of the K-group) signs of infectious intoxication were detected. In patients with gastrointestinal lesions, an elongation of the febrile period by 91.5 days was noted, a later (6 days) verification of the viral etiology of the disease. It was found that in patients of group I, the regression of clinical symptoms, the duration of viral disease, the dynamics of antibody formation, the prognosis for the development of IBS-like disorders in the post-infectious period depended on the treatment. In patients taking (Zacofalk), these indicators were significantly better. CONCLUSION: In mild cases, to reduce the severity of viral intestinal damage, for effective relief of intestinal symptoms, to reduce the risk of IBS-like symptoms, it is advisable to prescribe (Zacofalk) in an initial dose of 3 tablets per day.
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COVID-19 , Enfermedades Gastrointestinales , Humanos , Antidiarreicos , COVID-19/complicaciones , Diarrea/tratamiento farmacológico , Diarrea/epidemiología , Diarrea/etiología , SARS-CoV-2RESUMEN
We perform an experimental and theoretical study of a novel distributed quasi-Bragg splitter for cold atoms propagating in crossed optical waveguides. The atoms are guided by horizontal red-detuned laser beams which cross with an angle of roughly 90°. The lattice formed by the interference between the two waveguides is used as a quasi-Bragg splitter to continuously deflect the atomic flux from one waveguide into the other. In the limit of strong waveguide confinement and depending on the velocity of the cloud, three main regimes are observed corresponding (1) to the absence of reflection, (2) to partial reflection and (3) to full reflection into the second waveguide. In view of the application to atom interferometry, the condition to split the cloud into mainly two equally-populated fragments is only met in the highest velocity regime, where the fraction of reflected and transmitted atoms can be controlled by tuning the lattice height. A diagnostic of the momentum distribution shows that a quasi-Bragg splitter with the occupation of mainly two momentum states is achieved in this regime. This behaviour can be understood by considering the band structure associated with the potential in the crossing region and agrees with numerical simulations of the atomic dynamics.
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The evolution of the transverse momentum of monochromatic light entering a multimode planar waveguide at large angle is investigated. We report on oscillations of the momentum caused by the beatings between the adjacent populated modes of the waveguide and their periodic collapses and revivals. A new type of an interferometer based on this effect with fringe spacing as small as lambda/9 is demonstrated experimentally, and periods as small as lambda/1000 seem to be feasible.
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Cartílago/anatomía & histología , Cartílago/cirugía , Terapia por Láser/métodos , Animales , Fenómenos Biomecánicos , Biotecnología , Cartílago/fisiología , Condrocitos/citología , Humanos , Técnicas In Vitro , Microscopía de Fuerza Atómica , Modelos Biológicos , Óptica y Fotónica , Dispersión de Radiación , Temperatura , Agua/metabolismoRESUMEN
We propose a new coherent atomic beam splitter that is based on the induced redistribution of photons in the intense field of two collinear standing waves with different frequencies. In the dressed-atom approach, we show that this scheme can provide a clear large-angle splitting into two components without being restricted to the Raman-Nath regime.
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One-dimensional localization of sodium atoms in a standing spherical light wave has been observed. The atoms have an oscillatory motion with an amplitude of approximately lambda/10 along the nodes (or loops) of the wave.
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A chemical-enzymatic synthesis of 271- and 286-bp DNA duplexes, each of which contains the entire sequence coding for human proinsulin has been accomplished. In addition to the coding sequence, the 271-bp fragment carries translation initiation and termination signals plus EcoRI-HindIII restriction enzyme sites for insertion into an appropriate plasmid vector. The 286-bp fragment also contains a Shine-Dalgarno (SD) sequence preceding an ATG codon. Employing the 286-bp polynucleotide, the 568-bp tandem proinsulin gene has been obtained. The synthesis of these DNA fragments involved preparation of 42 oligonucleotides by a rapid N-methylimidazolide phosphotriester method and enzymatic conversion of the oligonucleotides into the gene subfragments, which were cloned separately and fused to yield the desired DNAs coding for proinsulin. The proinsulin gene fragments were cloned in Escherichia coli and shown to have the correct sequences.
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Genes Sintéticos , Proinsulina/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , ADN/síntesis química , ADN Recombinante/análisis , Escherichia coli/genética , Genes , Genes Reguladores , Vectores Genéticos , Humanos , PlásmidosRESUMEN
The complete amino acid sequence of the oligomycin sensitivity-conferring protein (OSCP) of beef-heart mitochondria is reported. The protein contains 190 amino acids and has a molecular mass of 20 967. Its structure is characterized by a concentration of charged amino acids in the two terminal segments (N 1-77 and C 128-190) of the protein, whereas its central region is more hydrophobic. The earlier reported homology of the protein with the delta-subunit of E. coli F1, based on the terminal amino acid sequences of OSCP, is further substantiated.
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Adenosina Trifosfatasas , Proteínas Portadoras , Escherichia coli/enzimología , Proteínas de la Membrana , Mitocondrias Cardíacas/enzimología , Secuencia de Aminoácidos , Animales , Evolución Biológica , Bovinos , Sustancias Macromoleculares , ATPasas de Translocación de Protón Mitocondriales , Oligomicinas/farmacologíaRESUMEN
Five recombinant plasmids, pBK2646, pBK611, pRC3, pRC4 and pRC5, carrying rpoB rifampicin-resistant RNA-polymerase genes were obtained. The sequence analysis of these plasmids revealed certain structural changes in the rpoB gene which specify corresponding alterations in the beta-subunit of RNA polymerase. Some functional properties of the corresponding mutant strains and their RNA polymerases have been investigated.
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ARN Polimerasas Dirigidas por ADN/genética , Escherichia coli/genética , ARN Polimerasa I/genética , Rifampin/farmacología , Secuencia de Bases , Farmacorresistencia Microbiana , Escherichia coli/efectos de los fármacos , Escherichia coli/enzimología , Genes Bacterianos , Genes Dominantes , Mutación , PlásmidosAsunto(s)
Proteínas Bacterianas/metabolismo , Escherichia coli/genética , Factores de Elongación de Péptidos , Proteínas Ribosómicas/metabolismo , Ribosomas/metabolismo , Electroforesis en Gel de Poliacrilamida , Escherichia coli/metabolismo , Factor G de Elongación Peptídica , Unión Proteica , Translocación GenéticaRESUMEN
The combined structural study of proteins and of their corresponding genes utilizing the methods of both protein and nucleotide chemistry greatly accelerates and considerably simplifies both the nucleotide and protein structure determination and, in particular, enhances the reliability of the analysis. This approach has been successfully applied in the primary structure determination of the beta and beta' subunits of Escherichia coli DNA-dependent RNA polymerase and of their structural genes, yielding a continuous nucleotide sequence (4714 base pairs) that embraces the entire rpoB gene, the initial part of the rpoC gene and the intercistronic region, together with the total amino acid sequence of the beta subunit, comprising 1342 residues, and the N-terminal sequence of the beta' subunit (176 residues).
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ADN Bacteriano/genética , ARN Polimerasas Dirigidas por ADN/genética , Escherichia coli/enzimología , Genes , Secuencia de Aminoácidos , Secuencia de Bases , Enzimas de Restricción del ADN , Sustancias Macromoleculares , PlásmidosAsunto(s)
Acetilcolina/metabolismo , Venenos Elapídicos/metabolismo , Neurotoxinas/metabolismo , Receptores Colinérgicos/metabolismo , Animales , Sitios de Unión , Órgano Eléctrico/metabolismo , Espectroscopía de Resonancia por Spin del Electrón , Peces , Cinética , Conformación Proteica , Espectrometría de FluorescenciaRESUMEN
Digestion of phage lambda imm434 DNA with restriction endonuclease EcoRI yields 7 fragments. The shortest among them (1287 bp) contains the right part of the phage 434 immunity region and the phage DNA portion proximal to it. The complete primary structure of this fragment has been determined using the chemical method of DNA sequencing. Hypothetical amino-acid sequences of proteins coded by the cro gene of phage 434 and the cII gene of phage lambda, as well as NH2-terminal amino-acid sequences of the cI protein of phage 434 and the O protein of phage lambda, have been deduced solely on the basis of the DNA sequence. The fragment studied contains also the pR and probably prm promoters and the oR operator of phage 434. The sequence coding for them differs from the respective DNA sequence of phage lambda.