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1.
JBRA Assist Reprod ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38530758

RESUMO

OBJECTIVE: Recent studies have described a significant role for neutrophils in reproductive processes and their participation in the preparation of the cervix for childbirth and the activation of labor, in the postpartum involution of the uterus, and in the occurrence of preeclampsia. This study aimed to assess the formation of free radicals by neutrophils in the blood of women on the first day after childbirth and to characterize the adrenergic effect on this process. METHODS: Venous blood samples from 100 female volunteers aged 26-32 years who had 2 or 3 full-term deliveries were collected and analyzed. Various adrenergic compounds were considered (agonists alphaand betaadrenoreceptors, adrenoblockers). The intensity of the respiratory burst of neutrophils and the effect of adrenergic substances on them were assessed with latex-induced luminol-dependent chemiluminescence. RESULTS: Neutrophil activity depends on the stage of the woman's reproductive process: it decreases during pregnancy, reaches the lowest values during childbirth, and increases significantly in the first hours after childbirth. On the first day after childbirth, alpha-1-adrenergic receptors are highly active in neutrophils, through which NADP-H-oxidase is activated and activated oxygen species are formed. At the same time, alphaor beta-agonists inhibit the radical activity of cells. CONCLUSIONS: Latex-induced oxidative burst of female blood neutrophils correlates with the stage of the reproductive process. Stressful conditions in the postpartum period can suppress the ability of neutrophils to release reactive oxygen species, which increases the risk of postpartum infections.

2.
Biopreserv Biobank ; 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38190112

RESUMO

We researched the ability of tanacetan pectin from inflorescences of common tansy Tanacetum vulgare L. to change the osmolarity and freezing point of water in solutions of cryoprotectants: glycerol-3.5%, dimethyl sulfoxide (DMSO)-10%, dimethylacetamide-10% (DMAC), and 1.2-propanediol (1.2-PD)-10%, as well as the effect of solutions of tanacetan (0.2%, 0.4%) on the kinetics of crystallization processes and the nature of crystal formation. We used a combination of protector and pectin that we tested earlier, which provided effective protection for human leukocytes and platelets, as well as bovine spermatozoa, at temperatures below freezing (-20°C and -80°C). It has been established that tanacetan slows down the process of water freezing in glycerol, but not in DMSO, DMAC, and 1.2-PD, promotes deeper supercooling of the medium, and affects the morphological structure of ice. The addition of pectin to the cryosolution increases the activity of the main cryoprotectant glycerol even at its low concentrations. The combination of glycerol and tanacetan can be effective in freezing biological materials, which is confirmed by the preservation of leukocytes at -20°C and -80°C for 7 days, platelets at -80°C for 30 days, and spermatozoa at -80°C within 1 day. A comprehensive analysis of the chemical, physicochemical, and cryoprotective properties of tanacetan indicates the prospect of using pectin in the cryopreservation of biological objects at temperatures of electric freezers.

3.
Braz. arch. biol. technol ; 62: e19180204, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1011539

RESUMO

Abstract The subject of the study was the stability of human white blood cell membranes subject to noble gases (xenon ad krypton, 0.6 mPa) clathrate cryoanabiosis (‒80°C). A unique portable stainless steel low pressure container with a compartment for flexible plastic container was designed to ensure that the cells are saturated with gases. The samples were warmed after 1 and 30 days in a water bath (+38°C) for 35-50 sec, while the container was being tilted (2-3 times per second), until the temperature of the biological object reached +3±1°C. It was demonstrated that after 30 days of clathrate anabiosis (-80°C) over 95% (of the original number) of leukocytes remain viable, and cell membranes of 54.5±3.4% of them is resistant to trypan blue; granulocyte survival rate is 73.5±2.7%, original lipid peroxidation rate and antioxidant activity are retained. Biological object cryopreservation in noble gases environment is a promising trend in biology and medicine.


Assuntos
Xenônio , Criopreservação , Leucócitos , Células Sanguíneas , Criptônio
4.
Biopreserv Biobank ; 13(4): 240-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26186407

RESUMO

The use of carbohydrates as cryoprotectants is increasing. In this study the effects of incorporating polysaccharides extracted from plants and microalgae originating in northern Russia, into cryoprotectant solutions used to preserve human white blood cells were investigated. Cells in the presence of the polysaccharides were cooled to either -40°C or -80°C, using a two-step cooling process. The morphological and functional indicators of the cryopreserved leukocytes were assessed by light microscopy. When combined with glycerol, the pectin-polysaccharides Lemnan from common duckweed (Lemna minor L.) and Comaruman from marsh cinquefoil (Comarum palustre L), were capable of lowering the freezing point of the cryoprotectant solution and helped to preserve the integrity of the human white blood cell membranes at temperatures below zero. In addition, the increase in phagocytic activity of neutrophils was confirmed. In the context of the contemporary search for effective cell cryoprotectants, the results of this research demonstrate that the cryopreservation of biospecimens in a polysaccharide environment is a promising trend in applied medicine, which can be considered an alternative to traditional cryogenic nitrogen techniques.


Assuntos
Criopreservação/métodos , Crioprotetores/química , Leucócitos/citologia , Microalgas/química , Plantas/química , Polissacarídeos/química , Adulto , Carboidratos/química , Glicerol/química , Humanos , Leucócitos/metabolismo , Concentração Osmolar , Pectinas/química , Fagocitose , Federação Russa , Temperatura
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