18 research outputs found
Телемедицина: перспективы развития
Необходимость развития в условиях цифровой экономики такого направления как телемедицина кажется необходимостью, однако существует противоречие между существующими проблемами в системе организации здравоохранения Российской Федерации и возможностями доступности к услугам телемедицины. Анализ показал, что данное направление востребовано, необходимо, существует ряд сервисов, предлагающих услуги по телемедицине, однако нормативно-правовая база не позволяет в полной мере организовать полноценную работу по предоставлению телемедицинских услуг, в том числе, бесплатных
Математичні основи визначення функціонального стану операторів складних технологічних об’єктів
Забезпечення високої надійності роботи оператора, а, відповідно, системи «людина – машина» (СЛМ), – є пріоритетним завданням для більшості сфер промисловості та сучасного виробництва. Тому важливим є розробка заходів по підвищенню кваліфікації операторів складних технологічних об’єктів (СТО), шляхом підбору математичного апарату для який б дав можливість підвищити надійність його діяльності в структурі СЛМ
Expression of Tas1 Taste Receptors in Mammalian Spermatozoa: Functional Role of Tas1r1 in Regulating Basal Ca2+ and cAMP Concentrations in Spermatozoa
Background: During their transit through the female genital tract, sperm have to recognize and discriminate numerous chemical compounds. However, our current knowledge of the molecular identity of appropriate chemosensory receptor proteins in sperm is still rudimentary. Considering that members of the Tas1r family of taste receptors are able to discriminate between a broad diversity of hydrophilic chemosensory substances, the expression of taste receptors in mammalian spermatozoa was examined.
Methodology/Principal Findings:
The present manuscript documents that Tas1r1 and Tas1r3, which form the functional receptor for monosodium glutamate (umami) in taste buds on the tongue, are expressed in murine and human spermatozoa, where their localization is restricted to distinct segments of the flagellum and the acrosomal cap of the sperm head. Employing a Tas1r1-deficient mCherry reporter mouse strain, we found that Tas1r1 gene deletion resulted in spermatogenic abnormalities. In addition, a significant increase in spontaneous acrosomal reaction was observed in Tas1r1 null mutant sperm whereas acrosomal secretion triggered by isolated zona pellucida or the Ca2+ ionophore A23187 was not different from wild-type spermatozoa. Remarkably, cytosolic Ca2+ levels in freshly isolated Tas1r1-deficient sperm were significantly higher compared to wild-type cells. Moreover, a significantly higher basal cAMP concentration was detected in freshly isolated Tas1r1-deficient epididymal spermatozoa, whereas upon inhibition of phosphodiesterase or sperm capacitation, the amount of cAMP was not different between both genotypes.
Conclusions/Significance:
Since Ca2+ and cAMP control fundamental processes during the sequential process of fertilization, we propose that the identified taste receptors and coupled signaling cascades keep sperm in a chronically quiescent state until they arrive in the vicinity of the egg - either by constitutive receptor activity and/or by tonic receptor activation by gradients of diverse chemical compounds in different compartments of the female reproductive tract
Physiological investigations of signaling pathways in mature and immature male germ cells of mammals
In der vorliegenden Arbeit wurden physiologische Reaktionen von menschlichen Spermien im Zusammenhang mit Chemotaxis und Motilität untersucht. Dabei wurden Spermien verschiedenen Duftstoffen ausgesetzt und mit Hilfe bildgebender Verfahren die intrazelluläre Kalziumdynamik gemessen. Zusätzlich wurde die Akkumulation von Molekülen wie z.B. ATP mittels ELISA quantifiziert.
Weiterhin wurden in einem Kokulturansatz die ATP- und Hormonsignalgebung muriner Spermatogonien untersucht. Hierfür wurden kultivierte murine Spermatogonien verschiedenen Hormonen und ATP-Konzentrationen ausgesetzt und das Antwortverhalten mit Hilfe bildgebender Verfahren aufgezeichnet
Functional characterization of purinergic ion channels in single spermatogonia in vitro and in situ
Functional characterization of purinergic ion channels in single spermatogonia in vitro and in situ
Recommended from our members
Chemosensory Ca2+ dynamics correlate with diverse behavioral phenotypes in human sperm.
In the female reproductive tract, mammalian sperm undergo a regulated sequence of prefusion changes that "prime" sperm for fertilization. Among the least understood of these complex processes are the molecular mechanisms that underlie sperm guidance by environmental chemical cues. A "hard-wired" Ca(2+) signaling strategy that orchestrates specific motility patterns according to given functional requirements is an emerging concept for regulation of sperm swimming behavior. The molecular players involved, the spatiotemporal characteristics of such motility-associated Ca(2+) dynamics, and the relation between a distinct Ca(2+) signaling pattern and a behavioral sperm phenotype, however, remain largely unclear. Here, we report the functional characterization of two human sperm chemoreceptors. Using complementary molecular, physiological, and behavioral approaches, we comparatively describe sperm Ca(2+) responses to specific agonists of these novel receptors and bourgeonal, a known sperm chemoattractant. We further show that individual receptor activation induces specific Ca(2+) signaling patterns with unique spatiotemporal dynamics. These distinct Ca(2+) dynamics are correlated to a set of stimulus-specific stereotyped behavioral responses that could play vital roles during various stages of prefusion sperm-egg chemical communication