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1.
Artículo en Ruso | MEDLINE | ID: mdl-39422684

RESUMEN

Craniopharyngioma (CP) is a benign epithelial tumor predominantly localized in chiasmatic-sellar region and third ventricle. There are two histological variants of CP: adamantinoma-like (ACP, 85%) and papillomatous (PCP). These types differ significantly in origin and histological structure. PCP predominantly occurs in adults. Treatment of CP, including effectiveness of radiotherapy, is described in multiple studies and mainly devoted to pediatric patients. OBJECTIVE: To clarify disease-free survival in adults with newly diagnosed CP depending on resection quality; to evaluate the effectiveness of stereotactic irradiation and treatment depending on histological characteristics of tumor. MATERIAL AND METHODS: We analyzed treatment outcomes in 398 adults over 10-year follow-up. Stereotactic irradiation was performed in 11.6% of patients. The follow-up data were obtained in 68.1% of patients. We compared 5-year disease-free survival rates after different resections with and without subsequent irradiation. RESULTS: Total resection is effective and provides significantly lower risk of CP recurrence. Effectiveness of stereotactic irradiation after incomplete resection was also confirmed. CONCLUSION: Total resection of ACP and PCP provides high disease-free survival rates. Stereotactic irradiation after incomplete resection is followed by similar outcomes. PCPs are characterized by less aggressive growth and do not recur after total resection.


Asunto(s)
Craneofaringioma , Neoplasias Hipofisarias , Humanos , Craneofaringioma/cirugía , Craneofaringioma/mortalidad , Craneofaringioma/radioterapia , Adulto , Masculino , Femenino , Persona de Mediana Edad , Neoplasias Hipofisarias/cirugía , Neoplasias Hipofisarias/mortalidad , Neoplasias Hipofisarias/radioterapia , Neoplasias Hipofisarias/terapia , Neoplasias Hipofisarias/patología , Supervivencia sin Enfermedad , Adolescente , Radiocirugia/métodos , Anciano , Estudios de Seguimiento
2.
Zh Vopr Neirokhir Im N N Burdenko ; 88(5): 110-117, 2024.
Artículo en Ruso | MEDLINE | ID: mdl-39422691

RESUMEN

Craniopharyngiomas (CP) are benign chiasmatic-sellar tumors in children and adults. Surgical resection is currently the main method for CP and largely depends on topographic and anatomical location of tumor. OBJECTIVE: To analyze topographic and anatomical classifications of CP available in the world literature. MATERIAL AND METHODS: Searching for literature data on classifications of CPs was performed in the PubMed, eLibrary and CyberLeninka databases between 1960 and 2023. We used the following keywords: «craniopharyngioma¼, «third ventricle¼, «endoscopic transnasal surgery for craniopharyngiomas¼. RESULTS: We found 21 eligible manuscripts. The vast majority of studies are devoted to topographic and anatomical location of CPs in their own series: baseline growth along hypothalamic-pituitary axis (4 classifications), relation to the third ventricle (5 classifications), pituitary stalk (2 classifications), optic nerves (2 classifications) and meninges (3 classifications), classification of papillomatous CPs (1 report) and adamantinomatous CPs (1 report), functional classifications of hypothalamic lesions (3 reports). CONCLUSION: Topographic classifications of CPs characterize their relation to the most important basal brain structures: pituitary gland, hypothalamus, optic pathways and circle of Willis. There are also single topographic and anatomical classifications with emphasis on morphological component of CP. Exact anatomical and topographic variant of CP is often of decisive importance for choosing the optimal surgical approach, possibility and expediency of total resection. Further clarification of relationship of CP to diencephalic structures is associated with improvement of diagnostic methods, in particular, high-resolution MRI (7.0 T) and MR tractography.


Asunto(s)
Craneofaringioma , Neoplasias Hipofisarias , Craneofaringioma/clasificación , Craneofaringioma/cirugía , Craneofaringioma/diagnóstico por imagen , Craneofaringioma/patología , Humanos , Neoplasias Hipofisarias/clasificación , Neoplasias Hipofisarias/cirugía , Neoplasias Hipofisarias/diagnóstico por imagen , Neoplasias Hipofisarias/patología
3.
Bull Exp Biol Med ; 177(4): 423-426, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39264558

RESUMEN

The level of ROS (fluorescent probe 2',7'-dichlorodihydrofluorescein diacetate) and lipid content (fluorescent lipophilic dye Nile Red) in the peripheral blood monocyte fraction from patients with type 1 diabetes mellitus and healthy volunteers were assessed by flow cytofluorimetry. The number of CD36+ monocytes was assessed using specific antibodies. In patients with type 1 diabetes mellitus, the levels of ROS and intracellular lipids in monocytes and the number of cells expressing CD36 fatty acid translocase were elevated. These results indicate metabolic changes in the peripheral blood cells of patients with carbohydrate metabolism disorders and can be considered as possible prognostic markers for the development of type 1 diabetes mellitus complications.


Asunto(s)
Diabetes Mellitus Tipo 1 , Monocitos , Especies Reactivas de Oxígeno , Humanos , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/metabolismo , Monocitos/metabolismo , Masculino , Adulto , Femenino , Especies Reactivas de Oxígeno/metabolismo , Antígenos CD36/metabolismo , Antígenos CD36/sangre , Estudios de Casos y Controles , Citometría de Flujo , Adulto Joven , Metabolismo de los Lípidos
4.
Artículo en Inglés, Ruso | MEDLINE | ID: mdl-39169587

RESUMEN

Dysembryoplastic neuroepithelial tumor (DNET) is a benign mixed neuronal-glial neoplasm (WHO grade 1). DNET is most often localized in temporal lobes and found in children and young people with epilepsy. There a few cases of DNET in ventricular system with dissemination along the ependyma in the world literature. MATERIAL AND METHODS: We present a rare case of T1- and T2-negative ventricular system tumor. Only FIESTA imaging revealed dissemination with multiple focal lesions of the third ventricle, its bottom and lateral walls, anterior horns of lateral ventricles, cerebellar vermis, cervical and lumbar spinal cord. RESULTS: The patient underwent transcortical endoscopic biopsy of the third ventricle tumor with simultaneous ventriculoperitoneal shunting. DNET was diagnosed, and radiotherapy was subsequently performed. Literature data on this issue were analyzed. CONCLUSION: To date, disseminated forms of DNET are extremely rare. X-ray features and morphological results allow us to establish the correct diagnosis and determine further treatment strategy.


Asunto(s)
Neoplasias Neuroepiteliales , Humanos , Neoplasias del Ventrículo Cerebral/cirugía , Neoplasias del Ventrículo Cerebral/diagnóstico por imagen , Neoplasias del Ventrículo Cerebral/patología , Neoplasias del Ventrículo Cerebral/complicaciones , Neoplasias Neuroepiteliales/cirugía , Neoplasias Neuroepiteliales/diagnóstico por imagen , Neoplasias Neuroepiteliales/complicaciones , Neoplasias Neuroepiteliales/patología
5.
Rev Sci Instrum ; 95(4)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38624362

RESUMEN

An experimental platform is developed for the investigation of the Zeeman effect in strong magnetic fields. Mega-Gauss magnetic fields are generated by a 1 MA Zebra pulsed power machine using metal rod loads. A gas jet or CH oil on the load is the source of hydrogen. Excited hydrogen atoms are backlit by black body radiation from the rod load. Hydrogen absorption spectra are recorded with a grating spectrometer and intensified gated CCD camera. The experimental platform enables the observation of the quadratic Zeeman effect in hydrogen gas jets using the spectral shift of the central line in the Zeeman triplet. Other gases can be studied using the gas jet method.

6.
Khirurgiia (Mosk) ; (1): 110-118, 2024.
Artículo en Ruso | MEDLINE | ID: mdl-38258697

RESUMEN

OBJECTIVE: To evaluate the immediate results of ankle replacement with original prosthesis in a patient with severe post-traumatic deformation of the distal tibia. MATERIAL AND METHODS: When developing the original design of ankle prosthesis, we considered foreign analogues of classical and revision models of ankle prostheses taking into account their shortcomings. In this case, an integrated approach was used. Extensive work has been carried out to select materials for prosthetic components. Experimental work with mesenchymal stromal cells of bone marrow was aimed at testing cytotoxicity and biological compatibility. The staff of the department of designing biomechanical structures of the Research Institute of Bionics and Personalized Medicine of the Samara State Medical University carefully studied the proposed design of endoprosthesis using the Ansys software. After cadaver tests on full-scale models, we performed surgical intervention in a patient with severe post-traumatic deformity of the lower third of the left tibia. RESULTS: Our studies revealed convenience and certain advantages of intraoperative installation of original ankle prosthesis. Along with this, this clinical example indicated come features that must be taken into account in revision ankle replacement to avoid possible postoperative consequences. CONCLUSION: Original ankle prosthesis makes it possible to replace the distal tibia and preserve limb function.


Asunto(s)
Tobillo , Tibia , Humanos , Tibia/cirugía , Implantación de Prótesis , Biónica , Cadáver
7.
Bull Exp Biol Med ; 175(5): 625-628, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37874494

RESUMEN

Phenotypic characteristics of alveolar macrophages in the bronchoalveolar lavage fluid as well as their ability to acquire the M1 and M2 phenotypes during in vitro culturing with reprogramming factors were studied in rats with modeled diet-induced metabolic syndrome. A decrease in the number of alveolar macrophages with the M1 phenotype was found in animals with metabolic syndrome. The factors of metabolic syndrome do not affect phenotypic plasticity of cells in culture, but under the action of M2 reprogramming factors, the cells demonstrate a wide range of phenotypic plasticity by the CD80 and CD206 markers. The consistently high level of production of IL-6 and IL-10 by macrophages during culturing under different conditions indicates functional rigidity of the cells, which is probably a consequence of in vivo predetermined functional phenotype of these cells against the background of metabolic disorders.


Asunto(s)
Macrófagos Alveolares , Síndrome Metabólico , Ratas , Animales , Síndrome Metabólico/metabolismo , Macrófagos/metabolismo , Fenotipo , Líquido del Lavado Bronquioalveolar
8.
Bull Exp Biol Med ; 174(6): 719-722, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37157046

RESUMEN

Type 1 diabetes mellitus was modeled in Wistar rats by intraperitoneal injection of streptozotocin (25 mg/kg for 5 days), which led to the appearance of the main symptoms of insulin-dependent diabetes. In peripheral blood mononuclear cells isolated by centrifugation on a Ficoll density gradient, the production of ROS and the level of intracellular lipids were evaluated by flow cytofluorimetry. In rats with type 1 diabetes mellitus, an increase in ROS levels in isolated peripheral blood monocytes, but not in the lymphocytic fraction was revealed. Incubation of isolated monocytes in a medium containing 1 mM oleic acid led to a 1.5-fold increase of intracellular lipid levels. After incubation of the lymphocyte fraction in this medium, no differences from the control were revealed. Disorders of carbohydrate and lipid metabolism in type 1 diabetes mellitus leading to an increase of free fatty acids and ROS levels can be detected ex vivo in isolated peripheral blood mononuclear cells.


Asunto(s)
Diabetes Mellitus Tipo 1 , Ratas , Animales , Diabetes Mellitus Tipo 1/metabolismo , Leucocitos Mononucleares/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Ratas Wistar , Estrés Oxidativo , Ácidos Grasos no Esterificados/metabolismo
9.
Khirurgiia (Mosk) ; (5): 58-64, 2023.
Artículo en Ruso | MEDLINE | ID: mdl-37186652

RESUMEN

OBJECTIVE: Analysis of biomechanics of the first metatarsophalangeal joint after arthroplasty, interaction between bones and two implants of the first metatarsophalangeal joint using skeletal model of the foot. MATERIAL AND METHODS: We developed anatomically adapted all-ceramic non-coupled endoprosthesis of proximal interphalangeal joint between 2016 and 2021. To create a model of the foot, we used diagnostic computed tomography whose images were applied in 3D sculpting system and computer-aided design system for final geometric modeling of the joint. RESULTS: In dorsal flexion of the first metatarsophalangeal joint under 45° with the presence of implant, cortical bone tissue can withstand a load of up to 40 kg. Cortical bone tissue with implant can withstand a load of up to 305 kg without dorsal flexion. Strength of implant elements made of zirconium ceramics significantly exceeds strength of bone tissue within implant-bone tissue connection. CONCLUSION: Postoperative axial load on the first metatarsophalangeal joint up to 35 kg with maximum dorsal flexion up to 45° is the most appropriate. Higher load and hyperextension over 45° may be followed by postoperative complications such as implant instability, dislocation and periprosthetic fracture.


Asunto(s)
Artropatías , Prótesis Articulares , Articulación Metatarsofalángica , Humanos , Prótesis Articulares/efectos adversos , Fenómenos Biomecánicos , Articulación Metatarsofalángica/cirugía , Artropatías/cirugía , Complicaciones Posoperatorias/cirugía
10.
Bull Exp Biol Med ; 174(3): 330-332, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36723740

RESUMEN

In male Syrian hamsters fed a synthetic high-fat diet enriched with cholesterol (0.3%), administration of a polysaccharide from birch leaves L-rhamnopyranosyl-6-O-methyl-D-galacturonan (3 g/100 g of diet) resulted in a decrease in total cholesterol levels, mainly due to the LDL fraction, triglycerides, and bile acids in blood serum; the content of triglycerides and cholesterol in the liver also decreased, while excretion of bile acids with feces increased. Thus, the lipid-lowering effect of L-rhamnopyranosyl-6-O-methyl-D-galacturonan is related to its ability to bind bile acids in the intestine and interrupt their enterohepatic circulation.


Asunto(s)
Betula , Colesterol , Cricetinae , Masculino , Animales , Mesocricetus , Ácidos y Sales Biliares/metabolismo , Triglicéridos , Pectinas , Hígado/metabolismo , Dieta Alta en Grasa , Heces
11.
Bull Exp Biol Med ; 174(3): 333-336, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36723753

RESUMEN

We studied the effect of an indolinone derivative GRS on the development of experimental atherosclerosis in C57BL/6 mice. Atherosclerosis was modeled by intraperitoneal administration of endothelial lipoprotein lipase inhibitor Kolliphor P 407 micro Geismar over 5 months. GRS was administered orally in a dose of 10 mg/kg once a day throughout the experiment. In 5 months, the levels of total cholesterol, LDL, and triglycerides in blood serum, as well as histological composition of the ascending aorta were studied. In mice with experimental atherosclerosis, we observed pronounced dyslipidemia with an increase in serum cholesterol, LDL, and triglycerides and accumulation of xanthoma cells in the aorta wall. Repeat administration of GRS did not eliminate dyslipidemia, but prevented an increase in the number of xanthoma cells in the aorta wall (p<0.05). The stimulator of soluble guanylate cyclase GRS did not exhibit hypolipidemic activity, but restored impaired endothelial function in the atherosclerosis model and prevented atherosclerotic damage to blood vessels and vascular wall remodeling.


Asunto(s)
Aterosclerosis , Dislipidemias , Xantomatosis , Ratones , Animales , Guanilil Ciclasa Soluble , LDL-Colesterol , Ratones Endogámicos C57BL , Aterosclerosis/tratamiento farmacológico , Triglicéridos , Dislipidemias/tratamiento farmacológico , Guanilato Ciclasa
12.
Phys Rev E ; 106(4-2): 045206, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36397480

RESUMEN

The Zeeman effect is used for measurement of magnetic fields in astrophysical and laboratory plasmas. Magnetic fields in atmospheres of magnetic white dwarf stars are in the range 40 kG-1 GG. The quadratic Zeeman effect results in the additional split and shift of lines for magnetic fields >2 MG. Hydrogen Balmer lines were studied in magnetic fields delivered by a 1 MA pulse power generator. The magnetic field was generated by rod loads 0.8-1 mm in diameter. A droplet of CH oil on the load center was the source of hydrogen. A low ionized oil layer was backlit by blackbody emission from the rod with a temperature of 0.5-0.6 eV. Zeeman splitting of H-alpha and H-beta absorption lines were with a grating spectrometer. A spectral shift of the central component of the triplet indicated the quadratic Zeeman effect in hydrogen lines.

13.
Bull Exp Biol Med ; 173(4): 486-489, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36058975

RESUMEN

We studied contractile responses of isolated airway smooth muscle segments from rats with metabolic syndrome. Metabolic syndrome was induced in rats by high-fat and high-carbohydrate diet. It was shown that metabolic syndrome was associated with an increase of bronchoconstrictor action of cholinergic receptor activator carbacholine (0.1-100 µM) and a decrease of the dilatory effect of ß2-adrenoreceptor activator salbutamol (0.1-100 µM). The observed effects of agonists are epithelium-dependent. Disorders in contractile activity in the airway smooth muscles were accompanied by bronchial epithelium destruction, immune inflammation in the bronchial wall, muscular and peribronchial adipose tissue hypertrophy.


Asunto(s)
Broncoconstrictores , Síndrome Metabólico , Albuterol/farmacología , Animales , Bronquios , Broncoconstrictores/metabolismo , Broncoconstrictores/farmacología , Carbacol/metabolismo , Carbacol/farmacología , Carbohidratos/farmacología , Síndrome Metabólico/metabolismo , Contracción Muscular , Músculo Liso , Ratas , Receptores Colinérgicos/metabolismo
14.
Bull Exp Biol Med ; 172(6): 691-694, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35501647

RESUMEN

Experimental type 1 diabetes mellitus (T1DM) was induced in rats by daily intraperitoneal injections of alloxan in a dose of 90 mg/kg for 4 days. For verification of insulin resistance, insulin tolerance test was performed in 2 weeks and the glucose utilization rate constant (KITT) was calculated. The rats demonstrated the main symptoms of T1DM: hypoinsulinemia, hyperglycemia, ketonemia, glucosuria, ketonuria, polydipsia, polyphagia, weight loss, and insulin resistance, as evidenced by a decrease in KITT. The serum content of free fatty acids and triacylglycerols significantly increased. The content of triacylglycerols increased in skeletal muscles and decreased in the liver. A negative linear correlation was found between KITT and triacylglycerol content in muscles. Thus, the development of insulin resistance in experimental T1DM in rats is associated with accumulation of triacylglycerols in skeletal muscles.


Asunto(s)
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Resistencia a la Insulina , Animales , Glucemia , Diabetes Mellitus Tipo 1/inducido químicamente , Insulina , Resistencia a la Insulina/fisiología , Ratas , Triglicéridos
15.
Rev Sci Instrum ; 93(4): 043502, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35489931

RESUMEN

Plasma density measurements are key to a wide variety of high-energy-density (HED) and laboratory astrophysics experiments. We present a creative application of photonic Doppler velocimetry (PDV) from which time- and spatially resolved electron density measurements can be made. PDV has been implemented for the first time in close proximity, ∼6 cm, to the high-intensity radiation flux produced by a z-pinch dynamic hohlraum on the Z-machine. Multiple PDV probes were incorporated into the photoionized gas cell platform. Two probes, spaced 4 mm apart, were used to assess plasma density and uniformity in the central region of the gas cell during the formation of the plasma. Electron density time histories with subnanosecond resolution were extracted from PDV measurements taken from the gas cells fielded with neon at 15 Torr. As well, a null shot with no gas fill in the cell was fielded. A major achievement was the low noise high-quality measurements made in the harsh environment produced by the mega-joules of x-ray energy emitted at the collapse of the z-pinch implosion. To evaluate time dependent radiation induced effects in the fiber optic system, two PDV noise probes were included on either side of the gas cell. The success of this alternative use of PDV demonstrates that it is a reliable, precise, and affordable new electron density diagnostic for radiation driven experiments and more generally HED experiments.

16.
Bull Exp Biol Med ; 171(4): 431-434, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34542747

RESUMEN

We studied the effect of the H2S donor (NaHS, 1-500 µM) on the contractile responses of isolated aortic smooth muscle segments from rats with metabolic syndrome induced by high-fat, high-carbohydrate diet. It was found that the vasorelaxing effect of NaHS (5-100 µM) decreased in under conditions of MS. The endothelial NO synthase inhibitor L-NAME (100 µM) suppressed the effect of NaHS, while cystathionine-gamma-lyase inhibitor PAG (100 µM) decreased the vasodilating effects of acetylcholine (0.1-100 µM). Application of endogenous NO precursor L-arginine (1 mM) potentiated in the effects of H2S donor NaHS. Thus, the contractile activity of vascular smooth muscles in metabolic syndrome is determined by not only the effect of H2S, but also the influence of NO.


Asunto(s)
Sulfuro de Hidrógeno/farmacología , Enfermedades Metabólicas/fisiopatología , Contracción Muscular/efectos de los fármacos , Músculo Liso Vascular/efectos de los fármacos , Animales , Fenómenos Biomecánicos/efectos de los fármacos , Masculino , Enfermedades Metabólicas/patología , Síndrome Metabólico/patología , Síndrome Metabólico/fisiopatología , Músculo Liso Vascular/fisiología , NG-Nitroarginina Metil Éster/farmacología , Ratas , Ratas Wistar
17.
Sovrem Tekhnologii Med ; 13(1): 35-40, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34513064

RESUMEN

The aim of the study was to develop composite film materials derived from modified sodium carboxymethyl cellulose and to evaluate their anti-adhesive effects. Materials and Methods: The modified film materials were obtained by dissolving sodium carboxymethyl cellulose (Na-CMC) in an aqueous solution of a modifier (glycoluril) with subsequent homogenization and drying in a vacuum drying oven at room temperature. Physicomechanical parameters of the obtained films were determined using the Instron 3369 universal electromechanical testing machine (Great Britain) equipped with a climatic chamber (300-523 K), improved video extensometer, and the MKC-25 micrometer (Russia). Cytotoxicity of glycoluril-modified film materials derived from Na-CMC was studied by incubating cell cultures of 3T3-L1 mouse fibroblasts directly with extracts from films under study using a colorimetric test. Their anti-adhesion effect was investigated on 40 female Wistar rats by modeling a flat adhesion by inducing abrasion of the cecum and suturing the deserosed surface of the abdominal wall anatomically opposite the abrasion area. The presence of adhesions was assessed on day 8 after the operation. Commercial membrane Seprafilm (USA) was used as a reference sample. Results: It was found that extracts obtained from film materials derived from Na-CMC modified with glycoluril at a concentration of 0.01 and 0.05 wt. % had no cytotoxic effect on the cell culture of mouse fibroblasts 3T3-L1. Flat adhesions were not detected when using Seprafilm. When film materials under study were placed in the abdominal cavity between the injured areas, formation of flat adhesions was not observed or observed in one case out of ten. Conclusion: The obtained films are promising for preventing adhesions as a barrier-type agent. Modifying Na-CMC with glycoluril made it possible to create films that prevent formation of flat adhesions, have improved physical and mechanical properties and no cytotoxic effect.


Asunto(s)
Carboximetilcelulosa de Sodio , Sodio , Animales , Femenino , Imidazoles , Ratones , Ratas , Ratas Wistar , Adherencias Tisulares/prevención & control
18.
Bull Exp Biol Med ; 170(4): 415-419, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33713227

RESUMEN

We studied an original radiolabeled complex of antimicrobial peptides UBI29-41 and UBI18-35, ubiquicidin derivatives, for distinguishing between bacterial and aseptic inflammation. For radiolabeling of the peptides with technetium-99m, a bifunctional chelating agent succinimide-1-yl 6-(bis(pyridin-2-ylmethyl)amino)hexanoate was used. The obtained complexes 99mТс-DPAH-UBI29-41 and 99mТс-DPAH-UBI18-35 had radiolabeling yield >80% and radiochemical purity >96%. Accumulation of the complexes in the focus of bacterial inflammation in bone structures and the absence of this complex in the site of aseptic inflammation was confirmed in a rat model of traumatic osteomyelitis by single-photon emission computed tomography.


Asunto(s)
Osteomielitis/tratamiento farmacológico , Proteínas Citotóxicas Formadoras de Poros/química , Proteínas Ribosómicas/química , Tecnecio/química , Animales , Diagnóstico Diferencial , Femenino , Ratas , Ratas Wistar , Tomografía Computarizada de Emisión de Fotón Único
19.
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
20.
Environ Geochem Health ; 43(1): 91-112, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32748302

RESUMEN

One of the theories explaining the reasons for geophagy, which was proposed earlier by the authors of the article, consists in the assumption that animals need rare-earth elements (REE). In order to test this hypothesis, we studied the chemical composition of spring waters in the territory of the Caucasus Nature Reserve at three kudurs along the Achipsta River, as well as at the Mamaevsky kudur (southwestern slope of the Pshekish mountain). At the Mamaevsky kudur, we also studied the chemical composition of earth consumed by animals, and the species, age and gender composition, seasonal and daily activity of ungulate animals-visitors of the kudur. It was determined that the most active visitors of the Mamaevsky kudur were European bison (Bison bonasus) with one activity peak during the rut, in July. The frequency of visits to the kudur by red deer (Cervus elaphus) was 4 times lower with the highest peak activity in April and a lower peak in August. Only in one of four water sources at the Mamaevsky kudur there was an elevated concentration of Na (by 7 times). In the other three the concentration was comparable to the local river water. The waters of two "sodium-free" springs had increased concentrations of REE (by 5-8 times). Geophagic earths near the Mamaevsky springs are decomposition products of siltstone and sandstone shale rocks of the Jurassic age consisting of clay minerals (illite mixed with smectite, and chlorites)-from 42 to 45%, and quartz and feldspar (in total up to 50%) mixed with Fe and Ca carbonates. The chemical composition of acid extracts (0.1 N HCl, pH = 1.0) from consumed earth showed the highest extractability of Ca and Fe. In trace elements, Sr, Ba, Zn, Cu, Ni, Co, V, light lanthanides, and Y are most actively extracted. Na is extracted at 0.03-0.1 g/kg. The sodium bicarbonate spring water consumed by animals at kudurs on the Achipsta River had Na contents 70-300 times, and REE contents 25-40 times higher than that in the river water. The revealed facts do not contradict the hypothesis that the desire for geophagy in animals in the Caucasus (in addition to the long-known "urge" for Na) can be also related to the properties of lanthanides group elements exchange in the body.


Asunto(s)
Metales de Tierras Raras/análisis , Manantiales Naturales/química , Pica , Ríos/química , Suelo/química , Animales , Animales Salvajes , Federación de Rusia , Estaciones del Año , Oligoelementos/análisis
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