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1.
Vestn Oftalmol ; 139(2): 17-27, 2023.
Artículo en Ruso | MEDLINE | ID: mdl-37067928

RESUMEN

PURPOSE: Assessment of the indices of macular capillary blood flow and subfoveal choroidal thickness (SCT) using optical coherence tomography angiography in patients with retinal manifestations of ocular ischemic syndrome (RMOIS) associated with atherosclerotic internal carotid artery stenosis. MATERIAL AND METHODS: The study included 34 patients (68 eyes): 21 men, 13 women with RMOIS in one eye. All patients were divided into 2 groups depending on the severity of atherosclerotic internal carotid artery stenosis and ophthalmoscopic picture of the fundus. To obtain objective information we analyzed the degree of decrease in the main indices characterizing macular microcirculation and SCT depending on the severity of RMOIS. RESULTS AND DISCUSSION: Analysis of the results showed relationship between the severity of RMOIS and the deficit in macular microcirculation. The macula of the patients with mild RMOIS was characterized by a decrease in the density of superficial vascular plexus (SVP) and the density of deep capillary plexus (DCP) by 13.5% and 10.5% compared to the controls, respectively; in moderate RMOIS - by 19.7% and 14.6%; in severe RMOIS - by 35.9% and 28%, respectively. With an increase in the severity of RMOIS, the area of the foveal avascular zone increased too: in mild degree RMOIS - by 19%, in moderate - by 38.6%, in severe - by 51%. In proportion to the severity of RMOIS, SCT was reduced: in mild degree RMOIS - by only 8%, in moderate - by 22%, and in severe - by 29.8% of the control. CONCLUSION: The conducted research indicates that pathological changes in RMOIS extend to the entire capillary network of the macula and SCT. With increase in the degree of RMOIS, ischemic changes in all capillary layers of the central parts of the retina proportionally increase in comparison with the control group by 1.15 times in mild degree, by 1.24 times in moderate degree, and by 1.5 times in severe RMOIS.


Asunto(s)
Estenosis Carotídea , Mácula Lútea , Enfermedades de la Retina , Masculino , Humanos , Femenino , Vasos Retinianos/diagnóstico por imagen , Vasos Retinianos/patología , Angiografía con Fluoresceína/métodos , Tomografía de Coherencia Óptica/métodos , Estenosis Carotídea/patología , Mácula Lútea/diagnóstico por imagen , Mácula Lútea/irrigación sanguínea , Isquemia/diagnóstico por imagen , Isquemia/etiología
2.
Vestn Oftalmol ; 136(4): 66-74, 2020.
Artículo en Ruso | MEDLINE | ID: mdl-32779458

RESUMEN

Rhegmatogenous retinal detachment (RRD) is one of the most severe eye diseases typically occurring in people of working age. The annual rates of primary vision disability in patients with RRD is 2-9%. PURPOSE: To increase the functional effectiveness of endovitreal surgery in patients with RRD by including Cytoflavin in the system of postoperative rehabilitation. MATERIAL AND METHODS: The study involved 68 patients with RRD aged 37 to 65 years. Patients underwent vitrectomy using the 25 Gauge technology with endolaser coagulation of rupture zones and silicone oil tamponade in the vitreous cavity. Three months after the surgery, silicone oil was removed from the vitreous cavity. Patients were divided into 2 groups: the main - 34 people who received Cytoflavin in addition to standard therapy, and the control - 34 people receiving only standard postoperative treatment. The time course of the treatment's functional effectiveness was analyzed using best corrected visual acuity (BCVA) and macular photosensitivity. Laser Doppler flowmetry (LDF) was used to register the microcirculation and microcirculation efficiency indices. Morphological signs of macular ischemia were registered by optical coherence tomography angiography (OCT-A). RESULTS: Patients of the main group showed higher level of restoration of macular function compared with the control group. The increase in functional activity of the macular area correlated with postoperative dynamics of restoration of central retinal thickness. Analysis of LDF and OCT-A indices showed that improvement of visual functions in patients treated with Cytoflavin is directly related to restoration of chorioretinal blood flow. CONCLUSION: The use of Cytoflavin in patients after endovitreal surgery of RRD led to improvement of BCVA by an average of 2.6 times and photosensitivity of the macula by 2 times. The visual functions of patients improved after using Cytoflavin due to its positive effect on chorioretinal microcirculation and the density of macular capillary plexuses.


Asunto(s)
Mácula Lútea , Desprendimiento de Retina/cirugía , Adulto , Anciano , Humanos , Persona de Mediana Edad , Retina , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Agudeza Visual , Vitrectomía
3.
Vestn Oftalmol ; 135(2): 4-11, 2019.
Artículo en Ruso | MEDLINE | ID: mdl-31215528

RESUMEN

PURPOSE: To assess the etiological significance of herpesviral infection (HVI) in patients with acute idiopathic optic neuritis (ON) using clinical and laboratory monitoring. MATERIAL AND METHODS: Clinical and laboratory examinations were conducted for 10 years and were based on the results of etiological monitoring of 79 patients (85 eyes) with acute idiopathic ON in the period of 2005-2015. RESULTS: During a complex examination of 79 patients with acute idiopathic ON, various infectious pathogens were diagnosed in 75 people (94.9±2.1%). HVI was clearly dominant (69 patients - 87.3±2.4%). These patients were divided into 3 etiological groups. The first group - 34 people with herpesviral monoinfection; the second group - 15 people with mixed viral-viral infections; the third group - 20 people with mixed viral-bacterial infections. In the general population of patients with acute idiopathic ON associated with HVI, herpes simplex virus-1 is the most frequent (by more than 2.5 times), the infections of Epstein-Barr virus and cytomegalovirus were detected less often (p<0.05). Active current HVI in the general group of patients was diagnosed in 58 patients (84%). At the same time, reactivation of chronic infection (79.7%) was noted to be prevalent, while primary acute HVI was diagnosed rarely (4.3%). The remaining 11 patients (16%) had chronic persistent HVI. CONCLUSION: Clinical and laboratory monitoring of HVI in patients with acute idiopathic ON has shown the etiological role of herpesviruses in its development. Based on a complex of serological markers in enzyme-linked immunoassay reactions of blood serum, it was found that in patients with acute idiopathic ON the frequency of herpesviral infection is 87.3±2.4%. The proportion of active (etiologically significant) herpesviral infection is 84% of the total group. The results of the clinical and laboratory studies are of great practical importance for verification of the etiologic diagnosis and selection of adequate etiopathogenetic therapy in patients with acute idiopathic ON associated with HVI.


Asunto(s)
Herpesviridae , Neuritis Óptica , Virosis , Enfermedad Aguda , Herpesvirus Humano 4 , Humanos , Simplexvirus
4.
Vestn Oftalmol ; 133(1): 19-26, 2017.
Artículo en Ruso | MEDLINE | ID: mdl-28291195

RESUMEN

AIM: to study the frequency of misdiagnosis of cataract in patients with optic nerve pathology or amblyopia and to identify its main causes. MATERIAL AND METHODS: The study enrolled 381 patients (381 eyes) wrongly diagnosed with cataract. A standard set of eye tests was performed. In-depth examination of the macular area was done through biomicroscopy with contactless aspheric lenses of 60 and 90 D. Part of the patients underwent optical coherence tomography and static perimetry as well as examination of electrical sensitivity threshold and electrical lability of the optic nerve. RESULTS: In 190 patients (190 eyes - 49.9%), the true cause of central vision impairment was optic nerve pathology associated with its partial atrophy of different origins: vascular (77.8%) or post-traumatic (22.2%). Glaucomatous atrophy of the optic nerve was found in 175 patients within the age range from 57 to 70 years (175 eyes - 45.9%). These were newly diagnosed cases of advanced open-angle glaucoma. In 16 eyes (4.2%), the true cause of low vision appeared to be amblyopia of some type: strabismic (9 eyes - 56.3%), refractive (4 eyes - 25%), or mixed (3 eyes - 18.7%). CONCLUSION: The main diagnostic errors of attending ophthalmologists were the following: underestimation of the discrepancy between low visual functions and small degree of lens opacity as well as the neglect of careful examination of the fundus (specifically, the optic disc and macula), additional perimetry, thorough history taking, and cover-testing for suspected amblyopia.


Asunto(s)
Ambliopía/diagnóstico , Catarata/diagnóstico , Errores Diagnósticos , Enfermedades del Nervio Óptico , Nervio Óptico , Anciano , Anciano de 80 o más Años , Ambliopía/fisiopatología , Extracción de Catarata , Diagnóstico Diferencial , Errores Diagnósticos/prevención & control , Errores Diagnósticos/estadística & datos numéricos , Femenino , Humanos , Masculino , Nervio Óptico/diagnóstico por imagen , Nervio Óptico/patología , Nervio Óptico/fisiopatología , Enfermedades del Nervio Óptico/complicaciones , Enfermedades del Nervio Óptico/diagnóstico , Enfermedades del Nervio Óptico/fisiopatología , Tomografía de Coherencia Óptica/métodos , Trastornos de la Visión/diagnóstico , Trastornos de la Visión/etiología , Pruebas del Campo Visual/métodos
5.
Mol Biol (Mosk) ; 50(2): 231-45, 2016.
Artículo en Ruso | MEDLINE | ID: mdl-27239843

RESUMEN

Sepsis is a generalized infection accompanied by response of the body that manifests in a clinical and laboratory syndrome, namely, in the systemic inflammatory response syndrome (SIRS) from the organism to the infection. Although sepsis is a widespread and life-threatening disease, the assortment of drugs for its treatment is mostly limited by antibiotics. Therefore, the search for new cellular targets for drug therapy of sepsis is an urgent task of modern medicine and pharmacology. One of the most promising targets is the adenosine A(2A) receptor (A(2A)AR). The activation of this receptor, which is mediated by extracellular adenosine, manifests in almost all types of immune cells (lymphocytes, monocytes, macrophages, and dendritic cells) and results in reducing the severity of inflammation and reperfusion injury in various tissues. The activation of adenosine A(2A) receptor inhibits the proliferation of T cells and production of proinflammatory cytokines, which contributes to the activation of the synthesis of anti-inflammatory cytokines, thereby suppressing the systemic response. For this reason, various selective A(2A)AR agonists and antagonists may be considered to be drug candidates for sepsis pharmacotherapy. Nevertheless, they remain only efficient ligands and objects of pre-clinical and clinical trials. This review examines the molecular mechanisms of inflammatory response in sepsis and the structure and functions of A(2A)AR and its role in the pathogenesis of sepsis, as well as examples of using agonists and antagonists of this receptor for the treatment of SIRS and sepsis.


Asunto(s)
Agonistas del Receptor de Adenosina A2/metabolismo , Terapia Molecular Dirigida , Receptor de Adenosina A2A/metabolismo , Sepsis/tratamiento farmacológico , Adenosina/uso terapéutico , Agonistas del Receptor de Adenosina A2/uso terapéutico , Proliferación Celular/efectos de los fármacos , Humanos , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Inflamación/patología , Linfocitos/efectos de los fármacos , Linfocitos/inmunología , Monocitos/efectos de los fármacos , Monocitos/inmunología , Sepsis/genética , Sepsis/patología
6.
Tsitologiia ; 58(2): 156-63, 2016.
Artículo en Ruso | MEDLINE | ID: mdl-27228663

RESUMEN

By means of spectrophotometric assay we investigated interaction of the dye Congo red (CR) with fibrils of model proteins--hen egg white lysozyme, recombinant human beta2-microglobulin (b2M) and recombinant human transthyretin (TTR). The commercial dye sample was found to contain a significant amount of impurities. Methods for the dye purification are disclosed and CR molar extinction coefficient at 490 nm (ε490) was determined to be 3.3 x 10(4) M(-1) x cm(-1) at pH above 6.0. Formation of the CR-fibril complex results in changes in the dye visible absorption spectrum. According to the data on titration of fibril solutions with excess of the dye, CR binds to lysozyme fibrils at a ratio of about 5 molecules per protein monomer within fibril structure, to b2M fibrils--about 4 molecules per monomer, to TTR fibrils--about 4 molecules per subunit of the protein.


Asunto(s)
Amiloide/química , Rojo Congo/química , Muramidasa/química , Tristetraprolina/química , Microglobulina beta-2/química , Animales , Embrión de Pollo , Rojo Congo/metabolismo , Matriz Extracelular/química , Humanos , Muramidasa/metabolismo , Prealbúmina/química
7.
Vestn Oftalmol ; 132(4): 54-61, 2016.
Artículo en Ruso | MEDLINE | ID: mdl-27600896

RESUMEN

AIM: to compare the effectiveness of biomicroscopy (BMS) and optical coherence tomography (OCT) in recognizing prognostically unfavorable signs in peripheral vitreoretinal dystrophy (PVRD) patients. MATERIAL AND METHODS: A total of 131 cases of equatorial PVRD (91 eyes of 56 patients) were assessed. The mean patient's age was 24.7 years. The length of the anterior-posterior axis of the eyeball averaged 25.36±1.12 mm. Prevalence of particular warning signs in PVRD patients at BMS or OCT was comparatively analyzed. RESULTS: In 46 eyes with lattice dystrophy it was difficult to determine the presence of vitreoretinal traction at BMS; at OCT, areas of retinal adhesion to the posterior hyaloid membrane (PHM) along the edges of PVRD zones were revealed in all eyes. Of 31 eyes with «snail tracks¼ defects of the retina, 6 were diagnosed at BMS; in OCT scans of these patients, the PHM appeared firmly fixed along the edges of PVRD zones in all cases. As to horseshoe retinal tears (valve-like tears), BMS allowed to visualize vitreoretinal tractions in 7 of 12 eyes, while OCT revealed a tight contact between the PHM and the apex of the retinal flap in 11 of 12 eyes. In 7 eyes with retinoschisis we failed to detect any retinal traction at either BMS or OCT. In «non-differentiable¼ PVRD, BMS was also not able to reveal any vitreoretinal traction, while OCT was - in all 12 cases. CONCLUSION: OCT has proved much more effective than BMS in recognizing prognostically unfavorable signs in particular clinical forms of PVRD, such as vitreoretinal tractions, retinal defects, and intraretinal cavities.


Asunto(s)
Microscopía/métodos , Distrofias Retinianas , Tomografía de Coherencia Óptica/métodos , Adolescente , Adulto , Investigación sobre la Eficacia Comparativa , Femenino , Humanos , Masculino , Oftalmoscopía/métodos , Reproducibilidad de los Resultados , Distrofias Retinianas/clasificación , Distrofias Retinianas/diagnóstico , Distrofias Retinianas/diagnóstico por imagen , Distrofias Retinianas/fisiopatología
8.
Klin Lab Diagn ; 61(6): 335-41, 2016 Jun.
Artículo en Ruso | MEDLINE | ID: mdl-30601623

RESUMEN

The role of Tamm-Horsfall protein in pathogenesis of urolithiasis was analyzed. The study of oligomeric forms of protein was carried out using technique of dynamic light scattering. The sampling of 57 patients with urolithiasis and 51 patients of control group of comparative age and gender were examined. The degree of purification of Tamm-Horsfall protein was controlled using denaturant electrophoresis in polyacridine amyl gel. The reversing change of oligomeric form of protein with molecule size 2 Mda in polymeric form 28 Mda under impact of guanidinhydrochloride. Under urolithiasis, the form of protein associated with non-organic components and with size of macromolecular complex larger than 1500 nm was detected. The diagnostic criterion of urolithiasis was proposed based on totality of biochemical and biophysical analyses of urine.


Asunto(s)
Ensayo de Inmunoadsorción Enzimática , Isoformas de Proteínas/orina , Urolitiasis/orina , Uromodulina/orina , Electroforesis , Femenino , Humanos , Masculino , Complejos Multiproteicos/orina , Urolitiasis/patología
9.
Mol Biol (Mosk) ; 49(4): 541-54, 2015.
Artículo en Ruso | MEDLINE | ID: mdl-26299853

RESUMEN

Ebola hemorrhagic fever (EHF) epidemic currently ongoing in West Africa is not the first among numerous epidemics in the continent. Yet it seems to be the worst EHF epidemic outbreak caused by Ebola virus Zaire since 1976 as regards its extremely large scale and rapid spread in the population. Experiments to study the agent have continued for more than 20 years. The EHF virus has a relatively simple genome with seven genes and additional reading frame resulting from RNA editing. While being of a relatively low genetic capacity, the virus can be ranked as a standard for pathogenicity with the ability to evade the host immune response in uttermost perfection. The EHF virus has similarities with retroviruses, but belongs to (-)RNA viruses of a nonretroviral origin. Genetic elements of the virus, NIRV, were detected in animal and human genomes. EHF virus glycoprotein (GP) is a class I fusion protein and shows more similarities than distinctions in tertiary structure with SIV and HIV gp41 proteins and even influenza virus hemagglutinin. EHF is an unusual infectious disease, and studying the molecular basis of its pathogenesis may contribute to new findings in therapy of severe conditions leading to a fatal outcome.

10.
Vestn Oftalmol ; 131(2): 68-75, 2015.
Artículo en Ruso | MEDLINE | ID: mdl-26080586

RESUMEN

AIM: To study the frequency of patients with macular pathology being wrongly diagnosed with cataract and possible reasons for this to occur. MATERIAL AND METHODS: A total of 1390 patients (1390 eyes), in whom cataract turned out to be not the main cause of visual impairment, were recruited as research subjects. To reveal the reasons for misdiagnosis, we resorted to methods of ophthalmic examination that are available at ambulatory care facilities, i.e. visual acuity measurement, slit lamp biomicroscopy of the anterior and posterior eye segments, direct and indirect ophthalmoscopy. RESULTS: In most patients (72.6%) visual acuity was decreased due to macular pathology, especially age-related macular degeneration (AMD)--736 eyes (72.9%). Less common were degenerative myopia (10%), idiopathic macular hole (8.4%), epiretinal macular fibrosis (5.1%), and secondary macular changes of vascular, traumatic, or inflammatory genesis (3.6%). In 76.6% of eyes with macular pathology ophthalmoscopy was perfectly feasible and could be performed by a local ophthalmologist. Only in 23.4% of cases there was a dense posterior capsule opacification or nuclear cataract that impeded visualization of macular structures. CONCLUSIONS: The main reason for misdiagnosis of macular pathology and referring the patient to cataract surgeon was the neglect of apparent discordance between visual acuity and lens transparency. One should aim at adequate assessment of macular zone by all means, including non-contact ophthalmoscopy with 60 or 90 D aspherical lenses or Hruby lens and red-free examination.


Asunto(s)
Catarata/diagnóstico , Mácula Lútea/patología , Enfermedades de la Retina/diagnóstico , Anciano , Diagnóstico Diferencial , Errores Diagnósticos , Técnicas de Diagnóstico Oftalmológico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Necesidades , Mejoramiento de la Calidad , Federación de Rusia , Agudeza Visual
11.
Vopr Virusol ; 58(5): 32-7, 2013.
Artículo en Ruso | MEDLINE | ID: mdl-24640169

RESUMEN

The diagnostic oligonucleotide microarray for subtyping of human and animal influenza A viruses (IAVs) was developed. We proposed a simple method of the fluorescent labeling of genomic segments of all known IAVs subtypes, the composition of the hybridization buffer, as well as the software of the data processing. 48 IAVs strains of different subtypes were analyzed using our microarray. All of them were identified, while 45 of 48 strains were unambiguously subtyped.


Asunto(s)
Genoma Viral , Virus de la Influenza A/clasificación , Tipificación Molecular/métodos , Análisis de Secuencia por Matrices de Oligonucleótidos/instrumentación , Infecciones por Orthomyxoviridae/virología , ARN Viral/clasificación , Programas Informáticos , Animales , Humanos , Virus de la Influenza A/genética , Virus de la Influenza A/aislamiento & purificación , Gripe Humana/diagnóstico , Gripe Humana/virología , Dispositivos Laboratorio en un Chip , Infecciones por Orthomyxoviridae/diagnóstico , ARN Viral/genética
12.
Biophys Chem ; 293: 106943, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36495688

RESUMEN

Hepatitis B virus core antigen (HBc) with the insertion of four external domains of the influenza A M2 protein (HBc/4M2e) form virus-like particles whose structure was studied using a combination of molecular modeling and cryo-electron microscopy (cryo-EM). It was also shown that self-assembling of the particles occurs inside bacterial cells, but despite the big inner volume of the core shell particle, purified HBc/4M2e contain an insignificant amount of bacterial proteins. It was shown that a fragment of the M2e corresponding to 4M2e insertion is prone to formation of amyloid-like fibrils. However, as the part of the immunodominant loop, M2e insertion does not show a tendency to intermolecular interaction. A full-atomic HBc-4M2e model with the resolution of about 3 Å (3.13 Å for particles of Т = 4 symmetry, 3.7 Å for particles of Т = 3 symmetry) was obtained by molecular modeling methods based on cryo-EM data.


Asunto(s)
Antígenos del Núcleo de la Hepatitis B , Proteínas de la Matriz Viral , Microscopía por Crioelectrón , Antígenos del Núcleo de la Hepatitis B/química , Virus de la Hepatitis B/química , Modelos Moleculares , Proteínas de la Matriz Viral/química
13.
Prep Biochem Biotechnol ; 41(4): 337-49, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21967335

RESUMEN

The possibility of obtaining recombinant fibrillogenic fusion proteins such as transthyretin (TTR) and ß2-microglobulin (ß2M) with a superfolder green fluorescent protein (sfGFP) was studied. According to the literature data, sfGFP is resistant to denaturating influences, does not aggregate during renaturation, possesses improved kinetic characteristics of folding, and folds well when fused to different polypeptides. The corresponding DNA constructs for expression in Escherichia coli were created. It could be shown that during expression of these constructs in E. coli, soluble forms of the fusion proteins are synthesized. Efficient isolation of the fusion proteins was performed with the help of nickel-affinity chromatography. For this purpose a polyhistidine sequence (6-His-tag) was incorporated into the C-terminus of the sfGFP. We could show that the purified fusion proteins contained full-size sequences of the most amyloidogenic TTR variant, TTR(L55P) and ß2M, and also sfGFP possessing fluorescent properties. In the course of fibrillogenesis both fusion proteins demonstrated their ability to form fibrils that were clearly detectable by atomic force microscopy. Furthermore, with the help of confocal microscopy we were able to reveal structures (exhibiting fluorescence) that are formed during fibrillogenesis. Thus, the use of sfGFP has made it possible to avoid formation of inclusion bodies (IB) during the synthesis of recombinant fusion proteins and to obtain soluble forms of TTR(L55P) and ß2M that are suitable for further studies.


Asunto(s)
Escherichia coli/genética , Proteínas Fluorescentes Verdes/genética , Prealbúmina/genética , Proteínas Recombinantes de Fusión/genética , Microglobulina beta-2/genética , Amiloide/ultraestructura , Expresión Génica , Proteínas Fluorescentes Verdes/química , Proteínas Fluorescentes Verdes/aislamiento & purificación , Humanos , Prealbúmina/química , Prealbúmina/aislamiento & purificación , Pliegue de Proteína , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/aislamiento & purificación , Microglobulina beta-2/química , Microglobulina beta-2/aislamiento & purificación
14.
Biochimie ; 190: 50-56, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34273416

RESUMEN

The influenza NS1 protein is involved in suppression of the host immune response. Recently, there is growing evidence that prion-like protein aggregation plays an important role in cellular signaling and immune responses. In this work, we obtained a recombinant, influenza A NS1 protein and showed that it is able to form amyloid-like fibrils in vitro. Using proteolysis and subsequent mass spectrometry, we showed that regions resistant to protease hydrolysis highly differ between the native NS1 form (NS1-N) and fibrillar form (NS1-F); this indicates that significant structural changes occur during fibril formation. We also found a protein fragment that is capable of inducing the process of fibrillogenesis at 37 °C. The discovery of the ability of NS1 to form amyloid-like fibrils may be relevant to uncovering relationships between influenza A infection and modulation of the immune response.


Asunto(s)
Amiloide/metabolismo , Proteínas no Estructurales Virales/genética , Proteínas no Estructurales Virales/metabolismo , Rojo Congo/química , Rojo Congo/metabolismo , Cinética , Microscopía de Fuerza Atómica , Microscopía Electrónica , Modelos Moleculares , Agregado de Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Proteínas no Estructurales Virales/química
15.
J Biomol Struct Dyn ; 39(12): 4375-4384, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32490728

RESUMEN

Two influenza A nucleoprotein variants (wild-type: G102R; and mutant: G102R and E292G) were studied with regard to macro-molecular interactions in oligomeric form (24-mers). The E292G mutation has been previously shown to provide cold adaptation. Molecular dynamics simulations of these complexes and trajectory analysis showed that the most significant difference between the obtained models was distance between nucleoprotein complex strands. The isolated complexes of two ribonucleoprotein variants were characterized by transmission electron microscopy and differential scanning fluorimetry (DSF). Presence of the E292G substitution was shown by DSF to affect nucleoprotein complex melting temperature. In the filament interface peptide model, it was shown that the peptide corresponding in primary structure to the wild-type NP (SGYDFEREGYS) is prone to temperature-dependent self-association, unlike the peptide corresponding to E292G substitution (SGYDFGREGYS). It was also shown that the SGYDFEREGYS peptide is capable of interacting with a monomeric nucleoprotein (wild type); this interaction's equilibrium dissociation constant is five orders of magnitude lower than for the SGYDFGREGYS peptide. Using small-angle neutron scattering (SANS), the supramolecular structures of isolated complexes of these proteins were studied at temperatures of 15, 32, and 37 °C. SANS data show that the structures of the studied complexes at elevated temperature differ from the rod-like particle model and react differently to temperature changes. The data suggest that the mechanism behind cold adaptation with E292G is associated with a weakening of the interaction between strands of the ribonucleoprotein complex and, as a result, the appearance of inter-chain interface flexibility necessary for complex function at low temperature.Communicated by Ramaswamy H. Sarma.


Asunto(s)
Virus de la Influenza A , Gripe Humana , Adaptación Fisiológica , Frío , Humanos , Virus de la Influenza A/genética , Nucleoproteínas/genética
16.
Vestn Oftalmol ; 125(5): 34-7, 2009.
Artículo en Ruso | MEDLINE | ID: mdl-19916332

RESUMEN

Patients with a family history of diabetes mellitus should undergo complex antistress protection of the macula for the prevention of its stress-induced lesions during cataract phacoemulsification with intraocular lens implantation. A differential algorithm of stress protection therapy has been developed in relation to the phase of surgical stress, the use of which is to enhance the tolerance of vegetovascular, hemodynamic, and metabolic systems to the aggressive components of surgical stress, thus reducing the incidence of transient subclinical and clinical macular edema.


Asunto(s)
Carnitina/uso terapéutico , ADN/uso terapéutico , Retinopatía Diabética/cirugía , Mácula Lútea/patología , Facoemulsificación/métodos , Complicaciones Posoperatorias/prevención & control , Estrés Fisiológico , Anciano , Carnitina/administración & dosificación , ADN/administración & dosificación , Quimioterapia Combinada , Estudios de Seguimiento , Hemodinámica , Humanos , Hidrocortisona/sangre , Implantación de Lentes Intraoculares/métodos , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Complicaciones Posoperatorias/sangre , Complicaciones Posoperatorias/fisiopatología , Factores de Riesgo , Resultado del Tratamiento , Complejo Vitamínico B/administración & dosificación , Complejo Vitamínico B/uso terapéutico
17.
Vestn Oftalmol ; 124(4): 22-5, 2008.
Artículo en Ruso | MEDLINE | ID: mdl-18756795

RESUMEN

Optical coherent tomography (OCT) shows that in patients with diabetes mellitus (DM), a macular morphological response to cataract phacoemulsification (CPE) with intaocular lens (IOL) implantation proceeds as 3 types: 1) areactive without macular morphological changes; 2) hyperreactive with the development of reversible subclinical macular edema; and 3) aggressive with the transition of stress-induced retinal morphological lesions to clinically significant diabetic macular edema. Morphological differences in OCT parameters were established to have impact on the effect of visual rehabilitation. Following 3-4 months of CPE with IOL implantation in DM patients with the areactive type of a macular morphological response to surgical stress, the increase in visual acuity exceeded that observed in the hyperactive and aggressive types of a macular response by 12.8 and 57.7%, respectively. The findings suggest that medical preventive measures reducing the negative consequences of surgical stress should be implemented in DM patients at catarrhal surgery.


Asunto(s)
Retinopatía Diabética/etiología , Implantación de Lentes Intraoculares , Mácula Lútea , Edema Macular/etiología , Facoemulsificación , Anciano , Retinopatía Diabética/diagnóstico , Estudios de Seguimiento , Humanos , Edema Macular/diagnóstico , Persona de Mediana Edad , Complicaciones Posoperatorias , Factores de Tiempo , Tomografía de Coherencia Óptica , Agudeza Visual
18.
Angiol Sosud Khir ; 14(2): 96-100, 2008.
Artículo en Ruso | MEDLINE | ID: mdl-19156058

RESUMEN

The present work was undertaken to evaluate a new minimally invasive method of surgical management of varicose disease by means of the TriVex unit. The method is based on transillumination of saphenous veins in an aqueous medium, which makes it possible to perform radical removal thereof form separate punctures under visual control with the help of a specially designed vein stripper. Transillumination-assisted phlebectomy (TIP) was compared with microphlebectomy (MPE) according to the Varady's technique. We operated on a total of one hundred and eight patients suffering from varicose disease of the lower extremities. All of them underwent duplex scanning of the veins. Group One (study group) was composed of fifty-six patients subjected to TIP within the scope of a comprehensive treatment for varicose disease. Group Two consisted of fifty-two patients who were subjected to removal of varicosely altered affluents on the crus by means of microphlebectomy. The results of surgical management for varicose disease were analysed according to the following parameters, the duration of a surgical intervention, intensity of the pain syndrome in the postoperative extremity, a cosmetic outcome by visual analogue scales, and the incidence rate of complications. The obtained findings demonstratively showed that the duration of the operation in the study group was substantially shorter, averagely amounting to 35.5+/-6.2 minutes, as compared with as long as 65.0+/-6.2 minutes (P<0.0001) in the control group. The number of incisions in the study group turned out to be also significantly less than that in the control group, amounting to 4.0+/-1.3 vs. 12.0+/-2.5 (p<0.0001), which largely contributed to both a decrease in the level of the pain syndrome and obtaining aesthetically pleasing cosmetic outcomes. Hence, TIP being a minimally invasive procedure in surgical management of varicose disease, by its clinical efficiency appeared to be not inferior and at least equivalent to microphlebectomy, displaying at the same time certain advantages over the latter, consisting in the very positive cosmetic outcome obtained, a lesser operative injury inflicted, and shorter terms of rehabilitation of the patients involved.


Asunto(s)
Extremidad Inferior/irrigación sanguínea , Extremidad Inferior/cirugía , Transiluminación/instrumentación , Várices/cirugía , Procedimientos Quirúrgicos Vasculares/instrumentación , Adulto , Anciano , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad
19.
Vopr Virusol ; 63(2): 68-76, 2018 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-36494924

RESUMEN

One of the main problems in the area of influenza prophylaxis and pandemic prevention is the development of cross-reactive vaccines, i.e. vaccines directed against all subtypes of human influenza viruses. Such vaccines are being developed in many countries for more than 10 years. A number of vaccines are presently undergoing clinical trials. We created Uniflu candidate vaccine based on recombinant HBc4M2e protein consisting of 4 tandem-connected copies of the highly conserved ectodomain of M2 protein of the influenza A virus. These 4 copies were genetically fused to the carrier protein, namely hepatitis B core antigen. Commercially available Derinat was used as adjuvant in the candidate vaccine. Preclinical studies on laboratory animals (mice, ferrets) demonstrated that immunization with Uniflu leads to significantly higher level of specific immunoglobulins in the blood and bronchoalveolar lavages. Moreover, it produces immunoglobulins belonging to subtype IgG2a that is the most important mediator of antibody-dependent cytotoxicity. The vaccine under review stimulates the proliferation of T-lymphocytes, as well as the formation of CD4+ and CD8+ T-cells synthesizing ɣ-IFN. When infected with the lethal doses (5 LD50) of influenza A viruses of the subtypes H1N1, H2N2, H3N2, and H1N1pdm09, immunized animals typically developed mild form of illness. This kept them alive in 90-100% of cases, which demonstrated almost complete protection from death. Replication of the virus in the lungs of immunized mice was reduced by 1.8-4.8 log10. High immunogenicity of the vaccine, and reduced clinical symptoms following experimental infection, were demonstrated in ferrets as well. The developed recombinant vaccine Uniflu has high specific activity and cross-protection. Uniflu can be proposed as pre-pandemic vaccine, provided that it passes clinical trials.

20.
Protein Pept Lett ; 14(5): 471-4, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17584173

RESUMEN

Symmetrical peptide GYDTQAIVENNESTEYG (WT, Wild Type) identical to 35-51 aminoacid residues of human alpha-lactalbumin (HLA) and peptide GYDTQTVVNNNGHTDYG (ID, IDeal symmetry) homologous to beta-domain of mammalian alpha-lactalbumins can form amyloid-like fibrils in conditions required for fibrillogenesis of HLA. The latter peptide can also form fibrils in deionized water. Fibrils formed by these peptides can cause forming of HLA amyloid-like aggregates in physiological conditions. These results provide an evidence for presence of amyloidogenic determinant in beta-domain of alpha-lactalbumin. Thus, symmetry in the primary structure may play the role in fibrillogenesis of proteins.


Asunto(s)
Lactalbúmina/química , Secuencia de Aminoácidos , Amiloide/biosíntesis , Humanos , Lactalbúmina/genética , Microscopía de Fuerza Atómica , Datos de Secuencia Molecular , Estructura Terciaria de Proteína , Homología de Secuencia
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