呼吸道病毒和呼吸道、肠道菌群的相互作用

随着新技术的应用,人们对人体不同部位的微生态系统有了进一步的认识,其中的微生物部分不仅指细菌还包括病毒。病毒的存在可以影响呼吸道和肠道菌群变化,同样呼吸道和肠道菌群状态也影响着病毒对人体的入侵程度。本研究就呼吸道和肠道菌群与呼吸道病毒相互作用关系的研究进展作一综述。     

Cardiovascular and respiratory functions

Abstract

In 649 patients during complex balneotherapeutic cure treatment and another 1053 patients during hydrotherapeutic cure treatment (according to Kneipp) blood pressure values were controlled. On an average, systolic and diastolic blood pressure values were reduced, however, at the same time subnormal initial values increased. The individual regression coefficients were significantly correlated with the initial values of systolic as well as of diastolic blood pressure. The cross‐over points of these correlations coincided with the normal values, proving so‐called normalization based on a process of functional adaptation, and this during both modes of treatment. The temporal distributions of maxima in the course of systolic and diastolic blood pressure exhibited a clear cut circaseptan periodic time structure passing the maxima around days 7, 14, and 21. This result again indicates that circaseptan periodicity represents the dominant characteristic time structure of functional adaptive processes leading to normalization.     

Mechanoreceptor system of the respiratory center and its contribution to respiratory control

The mechanoreceptor system of the respiratory center (RC) includes airway mechanoreceptors together with their conducting pathways and bulbar neuronal structures conveying impulses from mechanoreceptors to the RCV.A. A. Bogomolets Institute of Physiology, Ukrainian Academy of Sciences, Kiev. Translated from Neirofiziologiya, Vol. 24, No. 4, pp. 351–368, May–June, 1992.     

The respiratory center--the regulator of the respiratory system

The authors consider the respiratory centre to be the regulator of the respiratory system and to consist of 3 main functional blocks: chemoregulator, respiratory rhythm autogenerator and mechanoregulator, functions of which are provided by the neurons of medulla oblongata. The main aim of chemoregulator block is to maintain the level of ventilation volume speed, which is necessary to compensate the difference between the signals of setting and the firing from the chemoreceptors. The main aim of mechanoregulator block is to provide the functioning of the regulation loop of the respiratory muscles comparing the signals which come from the respiratory autogenerator, and the firing of the mechanoreceptors. The generator unit of the respiratory centre is a set of rhythm-forming associations, the system of 4 neurons (early and late inspiratory and expiratory) are typical among them. The neurons are connected by recurrent inhibitory bonds: the neuron of each rhythm-forming group, successively becoming excited, inhibits the two preceding neurons in the cycle; for all this the neuron of the successive group is released from inhibition and in such a way the rhythmogenesis occurs. The respiratory centre forms a common unit for chemo- and mechanoreceptor loops, through which the circuits of feedback for both loops are connected, providing the regulation of breathing.     

Static respiratory muscle work during immersion with positive and negative respiratory loading.

Upright immersion imposes a pressure imbalance across the thorax. This study examined the effects of air-delivery pressure on inspiratory muscle work during upright immersion. Eight subjects performed respiratory pressure-volume relaxation maneuvers while seated in air (control) and during immersion. Hydrostatic, respiratory elastic (lung and chest wall), and resultant static respiratory muscle work components were computed. During immersion, the effects of four air-delivery pressures were evaluated: mouth pressure (uncompensated); the pressure at the lung centroid (PL,c); and at PL,c +/-0.98 kPa. When breathing at pressures less than the PL,c, subjects generally defended an expiratory reserve volume (ERV) greater than the immersed relaxation volume, minus residual volume, resulting in additional inspiratory muscle work. The resultant static inspiratory muscle work, computed over a 1-liter tidal volume above the ERV, increased from 0.23 J. l(-1), when subjects were breathing at PL,c, to 0.83 J. l(-1) at PL,c -0.98 kPa (P < 0.05), and to 1.79 J. l(-1) at mouth pressure (P < 0.05). Under the control state, and during the above experimental conditions, static expiratory work was minimal. When breathing at PL,c +0.98 kPa, subjects adopted an ERV less than the immersed relaxation volume, minus residual volume, resulting in 0.36 J. l(-1) of expiratory muscle work. Thus static inspiratory muscle work varied with respiratory loading, whereas PL,c air supply minimized this work during upright immersion, restoring lung-tissue, chest-wall, and static muscle work to levels obtained in the control state.     

Chinchilla and murine models of upper respiratory tract infections with respiratory syncytial virus

Respiratory syncytial virus (RSV) is a major cause of lower respiratory tract infections in infants and the elderly. While the primary infection is the most serious, reinfection of the upper airway throughout life is the rule. Although relatively little is known about either RSV infection of the upper respiratory tract or host mucosal immunity to RSV, recent literature suggests that RSV is the predominant viral pathogen predisposing to bacterial otitis media (OM). Herein, we describe mouse and chinchilla models of RSV infection of the nasopharynx and Eustachian tube. Both rodent hosts were susceptible to RSV infection of the upper airway following intranasal challenge; however, the chinchilla proved to be more permissive than the mouse. The chinchilla model will likely be extremely useful to test the role of RSV in bacterial OM and the efficacy of RSV vaccine candidates designed to provide mucosal and cytotoxic T-lymphocyte immunity. Ultimately, we hope to investigate the relative ability of these candidates to potentially protect against viral predisposal to bacterial OM.     

Spectral analysis of respiratory parameters in defensive respiratory reflexes

A detailed analysis of respiratory signals in normal breathing and defensive respiratory reflexes was performed to obtain maximum information that can be used for modelling of respiratory processes. Physiological interpretation of the problem is difficult and requires further measurements to achieve convincing conclusions. We suggest therefore that the search for appropriate methodological backgrounds should contribute to further clarification of the problems concerned with reciprocal linkage of the respiratory signals. Appropriate attention must be paid to investigations aimed at explaining the regulatory mechanisms of breathing.     

Circulation of respiratory viruses in Moscow and their role in acute respiratory diseases morbidity

Statistical data obtained during prolonged investigations on the structure of infective agents isolated from patients with acute respiratory diseases (ARD) in Moscow in 1989-1999 were analyzed. The study revealed that fluctuations of ARD morbidity rates were linked with the prevailing circulation of one or another type of the virus. The absence of the dominating role of influenza viruses was confirmed. The conclusion was made on the necessity of using, in addition to influenza vaccinal prophylaxis, chemoprophylactic interventions to maintain ARD morbidity on the acceptable level.     

Activity of bulbar respiratory neurones during cough and other respiratory tract reflexes in cats

Changes evoked by mechanical stimulation of the relevant parts of the respiratory tract in the activity of inspiratory and expiratory neurones in the ventral respiratory group of the medulla oblongata, and in pleural pressure and the diaphragmatic electromyogram, were determined during cough, sneeze and the aspiration and expiration reflexes in 17 anaesthetized (but not paralysed) cats. The results of 72 tests of elicitation of the given reflexes showed that: Compared with the control inspiration, both the mean and the maximum discharge frequency of spontaneously active inspiratory neurones rose during the inspiratory phase of cough, sneeze and the aspiration reflex. Regular recruitment of new inspiratory units was also observed in the inspiratory phase of cough and the aspiration reflex. Compared with the control expiration, both the mean and the maximum discharge frequency of spontaneously active expiratory neurones rose during the cough, sneeze and expiration reflex effort. Recruitment of latent expiratory neurones was always observed in the expulsive phase of the given respiratory processes. The recruitment of latent expiratory neurones was accompanied by reciprocal inhibition of the activity of inspiratory units and recruitment of latent inspiratory neurones by inhibition of the activity of expiratory units and recruitment of latent inspiratory neurones by inhibition of the activity of expiratory units. Regular recruitment of the same expiratory neurones in all expulsive respiratory processes, together with the similar incidence of inspiratory neurones in the inspiratory phase of sneeze and the aspiration reflex, indicates that they are "nonspecific" in character.     

Nanocarriers as pulmonary drug delivery systems to treat and to diagnose respiratory and non respiratory diseases

The purpose of this review is to discuss the impact of nanocarriers administered by pulmonary route to treat and to diagnose respiratory and non respiratory diseases. Indeed, during the past 10 years, the removal of chlorofluorocarbon propellants from industrial and household products intended for the pulmonary route has lead to the developments of new alternative products. Amongst these ones, on one hand, a lot of attention has been focused to improve the bioavailability of marketed drugs intended for respiratory diseases and to develop new concepts for pulmonary administration of drugs and, on the other hand, to use the pulmonary route to administer drugs for systemic diseases. This has led to some marketed products through the last decade. Although the introduction of nanotechnology permitted to step over numerous problems and to improve the bioavailability of drugs, there are, however, unresolved delivery problems to be still addressed. These scientific and industrial innovations and challenges are discussed along this review together with an analysis of the current situation concerning the industrial developments.     

Severity of respiratory signs and symptoms and virus profiles in Japanese children with acute respiratory illness

Associations between the severity of respiratory signs and symptoms and the respiratory viruses identified in 214 Japanese children with acute respiratory illness (ARI) enrolled between January and December 2012 were studied. Respiratory rate, wheezing, cyanosis, and the use of accessory muscles were used as indices of respiratory severity and phylogenetic analysis of the viruses identified in these children was performed. Respiratory viruses such as respiratory syncytial virus (RSV), human rhinovirus (HRV), human parainfluenza virus (HPIV), and human metapneumovirus (HMPV) were prevalent, being detected in approximately 70% of the patients (151/214 patients). Co‐detection of viruses occurred in about 9% of patients. RSV was identified more frequently in cases scored as moderate/severe than in those scored as mild (P < 0.05). Severity scores of patients with RSV were significantly higher than those of cases with HPIV. Moreover, severity scores in patients with mild disease and co‐detections were higher than in those in whom only HPIV or adenovirus was detected. Phylogenetic analysis showed that many genotypes of HRV‐A and ‐C with wide genetic divergence were associated with acute respiratory illness (ARI). On the other hand, only a limited number of genotypes of RSV were associated with ARI. HPIV and HMPV were associated with ARI at similar frequencies. These results suggest that different respiratory viruses with unique genetic characteristics can be found in patients with mild to severe ARI.