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1.
Phys Rev Lett ; 132(23): 231903, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38905689

RESUMEN

The cross section of the process e^{+}e^{-}→π^{+}π^{-} has been measured in the center-of-mass energy range from 0.32 to 1.2 GeV with the CMD-3 detector at the electron-positron collider VEPP-2000. The measurement is based on an integrated luminosity of about 88 pb^{-1}, of which 62 pb^{-1} represent a complete dataset collected by CMD-3 at center-of-mass energies below 1 GeV. In the dominant region near the ρ resonance a systematic uncertainty of 0.7% was achieved. The implications of the presented results for the evaluation of the hadronic contribution to the anomalous magnetic moment of the muon are discussed.

2.
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
3.
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
4.
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
5.
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
6.
Bull Exp Biol Med ; 176(2): 137-142, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38189871

RESUMEN

NETosis, i.e., the formation of neutrophil extracellular traps (NET), and neutrophil autophagy are important elements in the pathogenesis and the development of complications of type 2 diabetes mellitus (T2DM). Therefore, the search of drugs that can regulate the level of NETosis and autophagy in T2DM is relevant. Here we studied an ex vivo NET formation and neutrophil death in whole blood from healthy subjects upon the addition of glucose up to a high concentration of 15 mM or/and the phorbol ester PMA (phorbol-12-myristate-13-acetate). Their individual and combined action caused neutrophil death and an increase in NET content. It can be hypothesized that this resulted from activation of NETosis and autophagy. It was also shown that this activation of NETosis and autophagy is completely prevented by daily intake of 1000 IU vitamin D3 for 14 days. Therefore, vitamin D3 supplementation can be considered as a preventive measure against the development of T2DM complications.


Asunto(s)
Diabetes Mellitus Tipo 2 , Trampas Extracelulares , Humanos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Neutrófilos , Glucosa/farmacología
7.
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
8.
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
9.
Opt Express ; 30(20): 35338-35347, 2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36258487

RESUMEN

A novel design of a grating-based optical pulse compressor is proposed. The proposed compressor provides a large group delay dispersion while keeping the compressor linear size small. The design of the proposed compressor is based on a traditional Treacy compressor with a straightforward modification of inserting two lenses between the compressor's gratings. This simple alternation aims to substantially increase group delay dispersion of the compressor or alternatively to decrease the compressor size while maintaining its group delay dispersion. A theoretical description of the enhanced compressor has been developed in the paraxial approximation. A detailed numerical model has been built to calculate the compressor parameters more accurately. These theoretical studies have revealed that the enhanced optical compressor provides a significant increase in the group delay dispersion compared to a standard Treacy compressor.

10.
Microb Ecol ; 83(4): 899-915, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34255112

RESUMEN

This article presents the first experimental data on the ability of microbial communities from sediments of the Gorevoy Utes natural oil seep to degrade petroleum hydrocarbons under anaerobic conditions. Like in marine ecosystems associated with oil discharge, available electron acceptors, in particular sulfate ions, affect the composition of the microbial community and the degree of hydrocarbon conversion. The cultivation of the surface sediments under sulfate-reducing conditions led to the formation of a more diverse bacterial community and greater loss of n-alkanes (28%) in comparison to methanogenic conditions (6%). Microbial communities of both surface and deep sediments are more oriented to degrade polycyclic aromatic hydrocarbons (PAHs), to which the degree of the PAH conversion testifies (up to 46%) irrespective of the present electron acceptors. Microorganisms with the uncultured closest homologues from thermal habitats, sediments of mud volcanoes, and environments contaminated with hydrocarbons mainly represented microbial communities of enrichment cultures. The members of the phyla Firmicutes, Chloroflexi, and Caldiserica (OP5), as well as the class Deltaproteobacteria and Methanomicrobia, were mostly found in enrichment cultures. The influence of gas-saturated fluids may be responsible for the presence in the bacterial 16S rRNA gene libraries of the sequences of "rare taxa": Planctomycetes, Ca. Atribacteria (OP9), Ca. Armatimonadetes (OP10), Ca. Latescibacteria (WS3), Ca. division (AC1), Ca. division (OP11), and Ca. Parcubacteria (OD1), which can be involved in hydrocarbon oxidation.


Asunto(s)
Euryarchaeota , Microbiota , Petróleo , Anaerobiosis , Bacterias/genética , Bacterias/metabolismo , Biodegradación Ambiental , Euryarchaeota/genética , Sedimentos Geológicos/microbiología , Hidrocarburos/metabolismo , Filogenia , ARN Ribosómico 16S/genética , ARN Ribosómico 16S/metabolismo , Sulfatos/metabolismo
11.
Inorg Chem ; 61(49): 19817-19827, 2022 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-36417701

RESUMEN

New high-entropy layered rare earth hydroxides ─ (Y,Eu,Gd,Er,Sm)2(OH)5NO3, (Y,Eu,Gd,Er,Tb)2(OH)5NO3, (Y,Eu,Gd,Er,Yb)2(OH)5NO3, (Y,Eu,Gd,Er,Nd)2(OH)5NO3, and (Y,Eu,Gd,Er,Nd,Sm,Tb)2(OH)5NO3 ─ were obtained using a hydrothermal microwave method. The annealing of layered rare earth hydroxides at 900 °C resulted in the corresponding high-entropy rare earth oxides. Based on inductively coupled plasma atomic emission spectroscopy data, the values for configurational entropy for both rare earth hydroxides and oxides were estimated, confirming the formation of high-entropy compounds. Energy-dispersive X-ray spectroscopy mapping, including mapping in the scanning transmission microscopy mode, showed no signs of chemical segregation and confirmed uniform rare earth elements' distribution both in the particles of high-entropy layered basic nitrates and in the particles of high-entropy oxides. The ratios of rare earth cations in the initial aqueous solutions of mixed nitrates were close to the ratios of cations in the resulting high-entropy layered rare earth basic nitrates and high-entropy rare earth oxides.


Asunto(s)
Metales de Tierras Raras , Metales de Tierras Raras/química , Hidróxidos/química , Óxidos/química , Nitratos
12.
J Therm Spray Technol ; 31(1-2): 307-314, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-37520905

RESUMEN

The abradable coatings had significantly enhanced turbomachinery performance by acting as a sacrificial seal between rotating blades and stationary casing. Further improvement in seal design to meet the higher energy demand and increase the service time has been the key challenge to solve in the gas turbine industry. Honeycomb seals have become the industry standard clearance seal technique due to their unique design and high structural strength with minimum weight. The present study proposes a concept to form a thermal shock resistance structure to achieve higher temperature capability and improve the reliability of high-temperature abradable seal structures for a hot gas path of turbines. A cavity layer of honeycomb seal structure made of SS 321 alloy was coated with advanced high-temperature ZrO2 + 7.5%Y2O3 + 4% polyester seal material using TriplexPro-210 plasma spray system. The integrity of a seal structure was assessed by a cross-sectional analysis and evaluation of the coating microstructure. Additionally, the micro-hardness test was performed to estimate coating fracture toughness, and finite element analysis was used to assess its thermo-mechanical performance. The concept proposed in this study should be further validated to develop the most capable innovative technology for advanced gas turbine abradable seal structures.

13.
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
14.
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
15.
Zh Vopr Neirokhir Im N N Burdenko ; 86(2): 103-108, 2022.
Artículo en Ruso | MEDLINE | ID: mdl-35412719

RESUMEN

OBJECTIVE: To demonstrate own experience in 3D modeling for planning of minimally invasive approach to the orbit and anterior skull base. MATERIAL AND METHODS: A 17-year-old patient admitted to the Department of Pediatric Neurosurgery with complaints of decreased visual acuity of the left eye, lacrimation and exophthalmos. MRI revealed a tumor of the left orbit. We have preoperatively modeled frontoorbital region, anterior skull, as well as eyeball and tumor within the same model. Considering young age and potentially favorable prognosis of disease, we preferred a minimally invasive intervention (microsurgical resection of tumor through minimally invasive frontoorbital access). RESULTS: Total resection of tumor was followed by examination of anterior skull base. There was postoperative regression of visual disturbances, lacrimation and exophthalmos. Sutures were removed after 5 days, and the patient was discharged. CONCLUSION: Minimally invasive frontoorbital access is adequate for approach to the orbit, anterior and middle cranial fossa, adequate resection of orbital tumor and examination of anterior skull base. 3D modeling is an additional preoperative tool to improve the quality of preoperative planning and facilitate intraoperative navigation.


Asunto(s)
Exoftalmia/cirugía , Órbita/cirugía , Neoplasias Orbitales/cirugía , Adolescente , Niño , Fosa Craneal Media , Exoftalmia/diagnóstico por imagen , Exoftalmia/etiología , Humanos , Imagenología Tridimensional , Procedimientos Quirúrgicos Mínimamente Invasivos , Procedimientos Neuroquirúrgicos , Órbita/diagnóstico por imagen , Neoplasias Orbitales/diagnóstico por imagen
16.
Khirurgiia (Mosk) ; (12. Vyp. 2): 44-53, 2022.
Artículo en Ruso | MEDLINE | ID: mdl-36562672

RESUMEN

Rectal cancer occupies the leading position among cancers, and incidence of locally advanced recurrences is still high despite comprehensive treatment. Combined resections are usually associated with high perioperative risks. These procedures are technically complex interventions requiring further improvement. Virtual reality technology in surgical treatment of locally advanced rectal cancer recurrence has not been widely discussed. The authors present multidisciplinary construction of the matched topographic-anatomical virtual model and virtual planning of the combined surgical intervention. Intraoperative use of augmented reality allowed specifying topographic and anatomical features of surgical area, level of vascular ligation, localization of tumor fixation points and resection borders. These data ensured safety and quality of resection. Further research of augmented reality technology and improvement of its technical aspects will improve the results of surgical treatment of patients with locally advanced pelvic tumors and recurrences.


Asunto(s)
Realidad Aumentada , Neoplasias del Recto , Humanos , Recurrencia Local de Neoplasia/cirugía , Recurrencia Local de Neoplasia/patología , Neoplasias del Recto/cirugía , Neoplasias del Recto/patología , Recto/cirugía
17.
Stomatologiia (Mosk) ; 101(2): 87-92, 2022.
Artículo en Ruso | MEDLINE | ID: mdl-35362709

RESUMEN

THE AIM OF THE STUDY: Was increasing of treatment effectiveness of patients with mouth floor odontogenic phlegmon (MFOP) by modified of surgical approach usage. MATERIALS AND METHODS: The prospective controlled, randomized, simple blinded clinical trial, II b level of evidence, comprised 86 patients with MFOP which formed main and control groups. The main group consisted of 40 patients treated with designed «Method for surgical treatment of odontogenic oral phlegmon of mouth floor with partial dissection of sublingual-submandibular sac¼. The control group involved 46 patients treated with traditional surgical procedure. The differences significance between the values has been evaluated with nonparametric Fisher's exact P-test and parametric Student's t-test for independent samples. RESULTS: The modified surgical approach statistically significantly (p<0.05) decreased the number of inflammatory complications (from 26±7% to 9±4%), terms of secondary sutures application (from 7.9±1.4 to 5.7±1.6 days) and time of hospital stay (from 9.4±1.8 to 8.3±1.7 days). On the 5th day of treatment white blood cells count in the main group was significantly (p<0.05) lower (7.2±1.1·109/l) than in controls (9.4±1.3·109/l) showing improved intoxication syndrome resolution in the main group. Index of reaction of bacteria adsorption to the oral epithelium in the main group on the 5th day of treatment was significantly (p<0.05) higher (77.1±6.9%) than in controls (62.4±7.1%). More successful correction of local non-specific resistance was registered in the main group. CONCLUSION: The proposed modified submandibular surgical approach is more effective for the treatment of patients with MFOP.


Asunto(s)
Celulitis (Flemón) , Suelo de la Boca , Celulitis (Flemón)/cirugía , Humanos , Suelo de la Boca/cirugía , Estudios Prospectivos , Glándula Submandibular , Resultado del Tratamiento
18.
Stomatologiia (Mosk) ; 101(5): 17-21, 2022.
Artículo en Ruso | MEDLINE | ID: mdl-36268914

RESUMEN

This article describes the use of augmented reality technology for the removal of an odontogenic cyst of the upper jaw. By combining the image of computed tomography, anatomical formations and the tip of the endoscope in mixed reality, a navigation system was created for performing cystectomy and resection of the tip of the molar root for a volumetric cyst of the maxillary sinus. For the first time, a system for tracking the position of an endoscope in mixed reality in real time was used.


Asunto(s)
Realidad Aumentada , Quistes , Humanos , Endoscopía/métodos , Tomografía Computarizada por Rayos X , Quistes/diagnóstico por imagen , Quistes/cirugía , Tecnología
19.
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
20.
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
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