Modulation of cough response by sensory inputs from the nose - role of trigeminal TRPA1 versus TRPM8 channels

BACKGROUND: Cough, the most important airways defensive mechanism is modulated by many afferent inputs either from respiratory tussigenic areas, but also by afferent drive from other organs. In animal models, modulation of cough by nasal afferent inputs can either facilitate or inhibit the cough response, depending on the type of trigeminal afferents stimulated. METHODS: In this study we addressed the question of possible bidirectional modulation of cough response in human healthy volunteers by nasal challenges with TRPA1 and TRPM8 agonists respectively. After nasal challenges with isocyanate (AITC), cinnamaldehyde, (−) menthol and (+) menthol (all 10(-3) M) nasal symptom score, cough threshold (C2), urge to cough (Cu) and cumulative cough response were measured). RESULTS: Nasal challenges with TRPA1 relevant agonists induced considerable nasal symptoms, significantly enhanced urge to cough (p<0.05) but no statistically significant modulation of the C2 and cumulative cough response. In contrast, both TRPM8 agonists administered to the nose significantly modulated all parameters including C2 (p<0.05), Cu (p<0.01) and cumulative cough response (p <0.01) documenting strong anti irritating potential of menthol isomers. CONCLUSIONS: In addition to trigeminal afferents expressing TRP channels, olfactory nerve endings, trigemino – olfactoric relationships, the smell perception process and other supramedullar influences should be considered as potential modulators of the cough response in humans

Short reflex expirations (expiration reflexes) induced by mechanical stimulation of the trachea in anesthetized cats

Fifty spontaneously breathing pentobarbital-anesthetized cats were used to determine the incidence rate and parameters of short reflex expirations induced by mechanical stimulation of the tracheal mucosa (ERt). The mechanical stimuli evoked coughs; in addition, 67.6% of the stimulation trials began with ERt. The expiration reflex mechanically induced from the glottis (ERg) was also analyzed (99.5% incidence, p < 0.001 compared to the incidence of ERt). We found that the amplitudes of abdominal, laryngeal abductor posterior cricoarytenoid, and laryngeal adductor thyroarytenoid electromyograms (EMG) were significantly enhanced in ERg relative to ERt. Peak intrathoracic pressure (esophageal or intra-pleural pressure) was higher during ERg than ERt. The interval between the peak in EMG activity of the posterior cricoarytenoid muscle and that of the EMG of abdominal muscles was lower in ERt compared to ERg. The duration of thyroarytenoid EMG activity associated with ERt was shorter than that in ERg. All other temporal features of the pattern of abdominal, posterior cricoarytenoid, and thyroarytenoid muscles EMGs were equivalent in ERt and ERg

Restoration of diaphragmatic function after diaphragm reinnervation by inferior laryngeal nerve; experimental study in rabbits

OBJECTIVES: To assess the possibilities of reinnervation in a paralyzed hemidiaphragm via an anastomosis between phrenic nerve and inferior laryngeal nerve in rabbits. Reinnervation of a paralyzed diaphragm could be an alternative to treat patients with ventilatory insufficiency due to upper cervical spine injuries. MATERIAL AND METHOD: Rabbits were divided into five groups of seven rabbits each. Groups I and II were respectively the healthy and the denervated control groups. The 3 other groups were all reinnervated using three different surgical procedures. In groups III and IV, phrenic nerve was respectively anastomosed with the abductor branch of the inferior laryngeal nerve and with the trunk of the inferior laryngeal nerve. In group V, the fifth and fourth cervical roots were respectively anastomosed with the abductor branch of the inferior laryngeal nerve and with the nerve of the sternothyroid muscle (originating from the hypoglossal nerve). Animals were evaluated 4 months later using electromyography, transdiaphragmatic pressure measurements, sonomicrometry and histological examination. RESULTS: A poor inspiratory activity was found in quiet breathing in the reinnervated groups, with an increasing pattern of activity during effort. In the reinnervated groups, transdiaphragmatic pressure measurements and sonomicrometry were higher in group III with no significant differencewith groups IV and V. CONCLUSION: Inspiratory contractility of an hemidiaphragm could be restored with immediate anastomosis after phrenic nerve section between phrenic nerve and inferior laryngeal nerve

All for one and one for all: Recommendations for Sustainable International Lunar Base Utilization and Exploration Approaches

The return to the Moon is widely regarded as the next step of space exploration. Fifty years after the first Apollo mission, a renewed interest is fostering large global efforts in pursuing the scientific and economic opportunities offered by cislunar space. The ultimate goal is to establish a sustainable human and robotic presence on the lunar surface as specified in Phase 2 of NASA’s Artemis Program. These perspectives are deeply intertwined with the rapid growth of the private space sector and the arising geopolitical complexities, related to utilisation of outer space among space-faring nations. This study summarises the results and recommendations of the NASA-sponsored Space Exploration Working Group within the Space Generation Congress 2019, organised by the Space Generation Advisory Council in Washington, D.C. The Working Group consisted of 26 delegates from 15 different countries and representatives from NASA Headquarters. The group examined the evolution of lunar exploration in terms of international cooperation, socio-economic and technological challenges, and the inclusion of private industry. This report discusses the political, economic, and technological trade-offs between a multi-agency/multinational monolithic lunar base to multiple lunar bases operated by individual nations. Using the International Space Station as a model for international cooperation, the working group concluded that an initial infrastructure of a single station requiring a collaborative effort between nations and commercial stakeholders is the recommended approach. From this foothold, the presence is expanded to multiple bases with a standardization of planning, building, and operating lunar bases. Strategic recommendations were identified to be addressed to the United Nations and other public/private stakeholders with the vision of a cooperative legal and technical framework as the optimal foundation for a sustainable lunar economy. Recommendations include developing international guidelines for cooperation, establishing international standards for stakeholders, implementing conflict resolution avenues, configuring a single international base, and expanding global partnerships

DMS-MOD: Modernising the Data Management Subsystem in the Columbus module of the ISS

Since its berthing to the International Space Station in 2008, the Columbus module has undergone several hardware upgrades. Columbus systems at launch were designed solely around CCSDS-based communication, requiring tailor-made ground and flight software for any incoming payloads. In order to reduce the complexity of integrating new payloads and thus maximise the scientific output of the module, Internet-protocol based communication hardware was installed in Columbus, starting with the European Multi-Purpose Communications Computer (MPCC). The most recent activity in modernising the Columbus Data Management System (DMS) involved transitioning from the two at-launch (“legacy”) Columbus LAN Switches (CLSW) to a new generation of LAN switches (CLSW Mk II). These new LAN switches offer new features and better integration of the systems present on-board the ISS, further bridging the gap between the legacy Columbus DMS components based on CCSDS protocol, and the IP-based MPCC, including the Columbus Ka-band terminal (Col Ka). The two CLSW Mk II are central components of Columbus LAN, utilised for communication between the individual DMS nodes in Columbus, as well as ESA and NASA payloads present in the module. The DMS modernisation project (also called DMS-Mod) also involved several support activities, such as deployment and installation of the Columbus Monitoring and Administration Unit (CMAU) required to support the operation of the switches, software updates to the MPCC system, and updates to the legacy systems reflecting the installation of the new hardware. This new system configuration is set to pave way for additional infrastructure, such as the Columbus Data Management Infrastructure (CDMI), to further expand IP-based operations within the module. The transition was successfully implemented on-board the ISS in the Columbus module, as well as on the ground, in January 2023. This paper describes the process of the hardware transition, the current architecture of the Columbus systems, and the future capabilities gained by modernising the Columbus DMS architecture

Upper Airway Control in Airway Defense

Upper airways (UA) are an organic component of the respiratory tract, they serve to respiration, respiratory tract protection and defense, phonation, deglutition, etc. The functions of UA are regulated by motor control of the oral, pharyngeal, and laryngeal muscles

Ultraviolet Radiation - Level of Knowledge and Health Protection of College Students in Slovakia. An Educational-Questionnaire Study

It is generally acknowledged that there is a correlation between the incidence of ultraviolet burden diseases and overexposure of the body to ultraviolet radiation (UVR). The main goals of our study were to determine the level of knowledge of college students in regard to the effects of UVR, to educate them about it, and finally to urge them to improve their personal protection against the harmful effects of UVR. We performed an educational-questionnaire study of UVR in 2003, 2005, and 2008 years. Responses of 841 students from Jessenius Faculty of Medicine in Martin (JFM), University of Zilina, and St. Elizabeth College of Health and Social Work (SEC) in Bratislava showed a higher level of knowledge in students at JFM and Univ. of Zilina following their education, as compared to those students from SEC. There was little difference in responses to questions related to the protection against UVR. A lower level of knowledge in all groups of students was shown in 2005. Nevertheless, all respondents significantly increased their level of protection against UVR during the years of the study and the number of those visiting solaria decreased. A weak relationship between the knowledge of students and their protection skills against UVR was found, indicating that a complex reason might be involved. This study highlights the importance of providing education that is systematic and longterm to university students in Slovakia (future doctors, bioengineers and nurses). Moreover, this study brings new insights on the surveillance and protection against the harmful effects of UVR to prospective patients

Influence of microinjections of D,L-homocysteic acid into the Bötzinger complex area on the cough reflex in the cat.

Microinjections of D,L-homocysteic acid (DLH) were used to test the hypothesis that neuronal activation within the Botzinger complex area can modify the spatiotemporal characteristics of the cough reflex in 17 spontaneously breathing pentobarbitone anesthetized cats. DLH (50 mM, 1.25-1.75 nmol, 9 cats) reduced the number (P&lt;0.01) of coughs and expiratory amplitude of abdominal electromyographic activity (P&lt;0.01), and also esophageal pressure (P&lt;0.001) during mechanically induced tracheobronchial cough. The duration of cough abdominal activity was shortened by 48% (P&lt;0.05). DLH microinjections also temporarily reduced the respiratory rate (P&lt;0.01) and increased the mean arterial blood pressure (P&lt;0.001), baseline of esophageal pressure (P&lt;0.01), and end tidal CO 2 concentrations (P&lt;0.01). Lower doses of 8 cats) induced few alterations in cardiorespiratory or cough characteristics. The results support predominantly inhibitory effects of neurons in the region of the Bötzinger complex on cough abdominal activity and cough number