Why respiratory viruses or bacteria have the highest probability to be deposited in the respiratory tract in flu seasons

Respiratory Infections ◽

Aerosol Deposition ◽

Climatic Conditions ◽

Submicron Particles ◽

Airborne Transmission ◽

Infected People ◽

Objective: In this study the main aspects of influenza transmission via fine and ultrafine bioaerosols were considered. Here, we aimed to estimate the impact of the different environment conditions on the deposition rate of the infectious bioaerosols in the respiratory tract. Background: The latest researches show the infected people generate the fine and ultrafine infectious bioaerosols with submicron particles/droplets (size below 1 µm). The airborne transmission of these particles/droplets in the environment is effective. It is considered the deposition of submicron particles in the respiratory tract (RT) has very low probability. But most studies examined the aerosol deposition in RT under normal environmental conditions and did not paid attention to the affecting the different environmental factors. Methods: We review the problems of epidemiology of respiratory infections and aspects of airborne transmission/spread of infectious agents. We contrast these approaches with known data from next areas: inhalation toxicology, respiratory drug delivery and physics of heat and mass transfer in the airways. Results: Based on the conducted analysis, we propose the next main concepts: 1 Breathing cool air leads to the supersaturation of air in RT; 2 the air supersaturation leads to the intensive condensational growth(CG) of inhaled viruses or bacteria in RT; 3 CG leads to the intensive and dramatically growth of deposition rate of viruses or bacteria in RT. We have shown: a) Under normal conditions of inhaled air (T>20˚C; Relatively Humidity, RH=60%) there is no transition in supersaturated condition in RT and CG is insignificant and probability of virus deposition on epithelium of RT is low – no more than 20%. b) Breathing cool/cold air of T<+15˚C and RH of [30..60]% leads to the supersaturation in the airways and it can dramatically increase the deposition rate of inhaled bioaerosols in RT(up to 96%). c) With an increase in RH of inhaled air the supersaturation in RT occurs even at warm temperature of inhaled air (for inhaled air of T<20°C and RH>70% ; T<25°C and RH>90%). Which also indicates the deposition rate of bioaerosols in RT under these conditions is high. Conclusion: Under specific environmental conditions (when flu seasons) the processes of supersaturation in the RT can be observed. These results indicate the high probability of virus deposition on epithelium of RT and correspond to influenza and seasonal respiratory infections in temperate and tropical climates. We believe the effect of supersaturation in the airways can be the key to understanding of ‘the age-old epidemiologic mystery of influenza seasonality in the different climatic conditions’.

Why respiratory viruses or bacteria have the highest probability to be deposited in the respiratory tract in flu seasons

10.7287/peerj.preprints.2237v4 ◽

2017 ◽

Author(s):

Aleksandr N Ishmatov

Keyword(s):

Respiratory Tract ◽

Deposition Rate ◽

Respiratory Infections ◽

Aerosol Deposition ◽

Climatic Conditions ◽

Submicron Particles ◽

Airborne Transmission ◽

Infected People ◽

Objective: In this study the main aspects of influenza transmission via fine and ultrafine bioaerosols were considered. Here, we aimed to estimate the impact of the different environment conditions on the deposition rate of the infectious bioaerosols in the respiratory tract. Background: The latest researches show the infected people generate the fine and ultrafine infectious bioaerosols with submicron particles/droplets (size below 1 µm). The airborne transmission of these particles/droplets in the environment is effective. It is considered the deposition of submicron particles in the respiratory tract (RT) has very low probability. But most studies examined the aerosol deposition in RT under normal environmental conditions and did not paid attention to the affecting the different environmental factors. Methods: We review the problems of epidemiology of respiratory infections and aspects of airborne transmission/spread of infectious agents. We contrast these approaches with known data from next areas: inhalation toxicology, respiratory drug delivery and physics of heat and mass transfer in the airways. Results: Based on the conducted analysis, we propose the next main concepts: 1 Breathing cool air leads to the supersaturation of air in RT; 2 the air supersaturation leads to the intensive condensational growth(CG) of inhaled viruses or bacteria in RT; 3 CG leads to the intensive and dramatically growth of deposition rate of viruses or bacteria in RT. We have shown: a) Under normal conditions of inhaled air (T>20˚C; Relatively Humidity, RH=60%) there is no transition in supersaturated condition in RT and CG is insignificant and probability of virus deposition on epithelium of RT is low – no more than 20%. b) Breathing cool/cold air of T<+15˚C and RH of [30..60]% leads to the supersaturation in the airways and it can dramatically increase the deposition rate of inhaled bioaerosols in RT(up to 96%). c) With an increase in RH of inhaled air the supersaturation in RT occurs even at warm temperature of inhaled air (for inhaled air of T<20°C and RH>70% ; T<25°C and RH>90%). Which also indicates the deposition rate of bioaerosols in RT under these conditions is high. Conclusion: Under specific environmental conditions (when flu seasons) the processes of supersaturation in the RT can be observed. These results indicate the high probability of virus deposition on epithelium of RT and correspond to influenza and seasonal respiratory infections in temperate and tropical climates. We believe the effect of supersaturation in the airways can be the key to understanding of ‘the age-old epidemiologic mystery of influenza seasonality in the different climatic conditions’.

Why respiratory viruses or bacteria have the highest probability to be deposited in the respiratory tract in flu seasons

10.7287/peerj.preprints.2237v3 ◽

2016 ◽

Author(s):

Aleksandr N Ishmatov

Keyword(s):

Respiratory Tract ◽

Deposition Rate ◽

Respiratory Infections ◽

Climatic Conditions ◽

Submicron Particles ◽

High Deposition Rate ◽

Airborne Transmission ◽

Infected People ◽

Objective: In this study the main aspects of influenza transmission via fine and ultrafine bioaerosols were considered. Here, we aimed to estimate the impact of the different environment conditions on the deposition rate of the infectious bioaerosols in the respiratory tract (RT). Background: The latest researches show the infected people generate the fine and ultrafine infectious bioaerosols with submicron particles/droplets (size below 1 µm). The airborne transmission of these particles/droplets in the environment is effective. It is considered the deposition of submicron particles in RT has very low probability. But most studies examined the deposition of the particles in RT under normal environmental conditions and did not paid attention to the different environmental factors. Methods: We review the problems of epidemiology of respiratory infections and aspects of airborne transmission/spread of infectious agents. We contrast these approaches with known data from next area: inhalation toxicology, respiratory drug delivery and physics of heat and mass transfer in the airways. Results: On the basis of these analyses, we propose the next main concepts: 1 Breathing cool air leads to the supersaturation of air in RT; 2 the air supersaturation leads to the intensive condensational growth(CG) of inhaled viruses or bacteria in RT; 3 CG leads to the intensive and dramatically growth of deposition rate of viruses or bacteria in RT. We have shown: a) Under normal conditions of inhaled air (T>20˚C; Relatively Humidity, RH=60%) there is no transition in supersaturated condition in RT and CG is insignificant and probability of virus deposition on epithelium of RT is low – no more than 20%. b) Breathing cool/cold air of T<+15˚C and RH of [30..60]% leads to the supersaturation in the airways and it can dramatically increase the deposition rate of inhaled bioaerosols in RT(up to 96%). c) With an increase in RH of inhaled air the supersaturation in RT occurs even at warm temperature of inhaled air (for inhaled air of T<20°C and RH>70% ; T<25°C and RH>90%). It also indicates the high deposition rate of bioaerosols in RT. Conclusion: Under specific environmental conditions (when flu seasons) the processes of supersaturation in the RT can be observed. These results indicate the high probability of virus deposition on epithelium of RT and correspond to influenza and seasonal respiratory infections in temperate and tropical climates. We believe the effect of supersaturation in the lungs can be the key to understanding of ‘the age-old epidemiologic mystery of influenza seasonality in the different climatic conditions.’

Why respiratory viruses or bacteria have the highest probability to be deposited in the respiratory tract in flu seasons

10.7287/peerj.preprints.2237v2 ◽

2016 ◽

Author(s):

Aleksandr N Ishmatov

Keyword(s):

Mass Transfer ◽

Respiratory Tract ◽

Heat And Mass Transfer ◽

Deposition Rate ◽

Respiratory Infections ◽

Submicron Particles ◽

Upper Respiratory Tract ◽

Airborne Transmission ◽

Objective: The main aspects of influenza transmission via fine and ultrafine bioaerosols were considered. Here, we aimed to estimate the impact of the different environment conditions on the processes of heat and mass transfer in the upper respiratory tract and its role in the deposition rate of the infectious bioaerosols in the lungs. Background: The latest researches show the infected people generate the fine and ultrafine infectious bioaerosols with submicron particles/droplets (size below 1 µm). The airborne transmission of these particles/droplets is effective. It is considered the deposition of submicron particles in the respiratory tract (RT) has very low probability. But most studies examined the deposition of the particles in the lungs under normal environmental conditions and did not paid attention to the different environmental factors. Methods: We review the problems of epidemiology of respiratory infections and aspects of airborne transmission/spread of infectious agents. We contrast these approaches with known data from next area: inhalation toxicology, respiratory drug delivery and physics of heat and mass transfer in the airways. Results: On the basis of these analyses, we propose the next main concepts: 1 Breathing cool air leads to the supersaturation of air in RT; 2 the air supersaturation leads to the intensive condensational growth(CG) of inhaled viruses or bacteria in RT; 3 CG leads to the intensive and dramatically growth of deposition rate of viruses or bacteria in RT. We have shown: a) Under normal conditions of inhaled air (T>20˚C; Relatively Humidity (RH)=60%) there is no transition in supersaturated condition in RT and CG is insignificant and probability of virus deposition on epithelium of RT is low – no more than 20%. b) Breathing cool/cold air of T<+15˚C and RH of [30..60]% leads to the supersaturation in the airways and it can dramatically increase the deposition rate of inhaled bioaresols in the lungs (up to 97%). c) With an increase in RH of inhaled air the supersaturation in RT occurs even at warm temperature of inhaled air (for inhaled air of T<20°C and RH>70% ; T<25°C and RH>90%). It also indicates the high deposition rate of bioaerosols in the lungs. Conclusion: Under specific environmental conditions (when flu seasons) the processes of supersaturation in the RT can be observed. These results indicate the high probability of virus deposition on epithelium of RT and correspond to influenza and seasonal respiratory infections in temperate and tropical climates. We believe the effect of supersaturation in the lungs can be the key to understanding of ‘the age-old epidemiologic mystery of influenza seasonality in the different climatic conditions’.

Why respiratory viruses or bacteria have the highest probability to be deposited in the respiratory tract in flu seasons

10.7287/peerj.preprints.2237v1 ◽

2016 ◽

Author(s):

Aleksandr N Ishmatov

Keyword(s):

Respiratory Tract ◽

Deposition Rate ◽

Liquid Water ◽

Population Biology ◽

Respiratory Infections ◽

Climatic Conditions ◽

Submicron Particles ◽

Cold Air ◽

Infected People ◽

Inhaled Particles

Marc Lipsitch and Cécile Viboud (2009) (Lipsitch and Viboud, 2009): “Seasonal variation in the incidence of communicable diseases is among the oldest observations in population biology, dating back at least to ancient Greece, yet our understanding of the mechanisms underlying this phenomenon remains hazy at best.” The latest researches show the infected people when breathing generate the infectious aerosols with particles below 1 µm. The airborne transmission of these particles is effective but the deposition of submicron particles in the respiratory tract (RT) has very low probability. Here I investigated the processes in RT when breathing cold air and its role in the delivery of viruses and bacteria of submicron and ultrafine sizes in RT. The original hypothesis of the highest probability of delivery and deposition of viruses or bacteria from inhaled air in the respiratory tract during flu seasons in different climatic conditions was investigated. On the basis of estimation I have originally shown: Breathing cool air leads to the supersaturation of air in RT; the air supersaturation leads to the intensive condensational growth(CG) of inhaled viruses or bacteria in RT; CG leads to the intensive and dramatically growth of deposition rate of viruses or bacteria in RT. Under normal conditions of inhaled air (T>20˚C; RH=60%) there is no transition in oversaturated condition in RT (CG is insignificant and probability of virus deposition on epithelium of RT is low – no more than 20%). But with an increase in RH of inhaled air the oversaturation in RT occurs even at warm temperature of inhaled air. For inhaled air of T=20°C, RH>70% the local supersaturation in the airways occurs: the concentration of liquid water in the mixed air in RT (СLiq) is СLiq<2·4g/kg and for T=25°C; RH>90% СLiq<1·2g/kg. The estimation also shown that for conditions of breathing cold air of T [-15..+15]˚C and Relatively Humidity (RH) of [30..60]% the supersaturation in the airways occurs: the concentration of liquid water in the mixed air in RT (СLiq) is [0·2..12·1]g/kg. Under these conditions the growth of inhaled particles by condensation in RT is significant. It lead to the dramatically growth of deposition rate of the viruses and bacteria in RT (up to 97%). These results correspond to influenza and seasonal respiratory infections in temperate and tropical climates and indicate the high probability of virus deposition on epithelium of RT. It may be the key to ‘the age-old epidemiologic mystery of influenza seasonality in the different climatic conditions’.

Defensive Properties of Mucin Glycoproteins during Respiratory Infections—Relevance for SARS-CoV-2

mBio ◽

10.1128/mbio.02374-20 ◽

2020 ◽

Vol 11 (6) ◽

Author(s):

Maitrayee Chatterjee ◽

Jos P. M. van Putten ◽

Karin Strijbis

Keyword(s):

Respiratory Tract ◽

Viral Infections ◽

Respiratory Infections ◽

Mucin Production ◽

Mucin Glycoproteins ◽

Microbial Invasion ◽

Age Related ◽

Mucin Expression ◽

Airway Mucus ◽

ABSTRACT Mucus plays a pivotal role in protecting the respiratory tract against microbial infections. It acts as a primary contact site to entrap microbes and facilitates their removal from the respiratory tract via the coordinated beating of motile cilia. The major components of airway mucus are heavily O-glycosylated mucin glycoproteins, divided into gel-forming mucins and transmembrane mucins. The gel-forming mucins MUC5AC and MUC5B are the primary structural components of airway mucus, and they enable efficient clearance of pathogens by mucociliary clearance. MUC5B is constitutively expressed in the healthy airway, whereas MUC5AC is upregulated in response to inflammatory challenge. MUC1, MUC4, and MUC16 are the three major transmembrane mucins of the respiratory tracts which prevent microbial invasion, can act as releasable decoy receptors, and activate intracellular signal transduction pathways. Pathogens have evolved virulence factors such as adhesins that facilitate interaction with specific mucins and mucin glycans, for example, terminal sialic acids. Mucin expression and glycosylation are dependent on the inflammatory state of the respiratory tract and are directly regulated by proinflammatory cytokines and microbial ligands. Gender and age also impact mucin glycosylation and expression through the female sex hormone estradiol and age-related downregulation of mucin production. Here, we discuss what is currently known about the role of respiratory mucins and their glycans during bacterial and viral infections of the airways and their relevance for the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Understanding the impact of microbe-mucin interaction in the respiratory tract could inspire the development of novel therapies to boost mucosal defense and combat respiratory infections.

Trichothecenes in Food and Feed, Relevance to Human and Animal Health and Methods of Detection: A Systematic Review

Molecules ◽

10.3390/molecules26020454 ◽

2021 ◽

Vol 26 (2) ◽

pp. 454

Author(s):

Magdalena Polak-Śliwińska ◽

Beata Paszczyk

Keyword(s):

Animal Health ◽

Agricultural Practices ◽

Climatic Conditions ◽

Toxic Effects ◽

Farm Animals ◽

Future Research ◽

Low Level ◽

Food And Feed ◽

Trichothecene mycotoxins are sesquiterpenoid compounds primarily produced by fungi in taxonomical genera such as Fusarium, Myrothecium, Stachybotrys, Trichothecium, and others, under specific climatic conditions on a worldwide basis. Fusarium mold is a major plant pathogen and produces a number of trichothecene mycotoxins including deoxynivalenol (or vomitoxin), nivalenol, diacetoxyscirpenol, and T-2 toxin, HT-2 toxin. Monogastrics are sensitive to vomitoxin, while poultry and ruminants appear to be less sensitive to some trichothecenes through microbial metabolism of trichothecenes in the gastrointestinal tract. Trichothecene mycotoxins occur worldwide however both total concentrations and the particular mix of toxins present vary with environmental conditions. Proper agricultural practices such as avoiding late harvests, removing overwintered stubble from fields, and avoiding a corn/wheat rotation that favors Fusarium growth in residue can reduce trichothecene contamination of grains. Due to the vague nature of toxic effects attributed to low concentrations of trichothecenes, a solid link between low level exposure and a specific trichothecene is difficult to establish. Multiple factors, such as nutrition, management, and environmental conditions impact animal health and need to be evaluated with the knowledge of the mycotoxin and concentrations known to cause adverse health effects. Future research evaluating the impact of low-level exposure on livestock may clarify the potential impact on immunity. Trichothecenes are rapidly excreted from animals, and residues in edible tissues, milk, or eggs are likely negligible. In chronic exposures to trichothecenes, once the contaminated feed is removed and exposure stopped, animals generally have an excellent prognosis for recovery. This review shows the occurrence of trichothecenes in food and feed in 2011–2020 and their toxic effects and provides a summary of the discussions on the potential public health concerns specifically related to trichothecenes residues in foods associated with the exposure of farm animals to mycotoxin-contaminated feeds and impact to human health. Moreover, the article discusses the methods of their detection.

Effect of Extreme Climate on Topology of Railway Prestressed Concrete Sleepers

Climate ◽

10.3390/cli7010017 ◽

2019 ◽

Vol 7 (1) ◽

pp. 17 ◽

Cited By ~ 4

Author(s):

Dan Li ◽

Sakdirat Kaewunruen

Keyword(s):

Relative Humidity ◽

Prestressed Concrete ◽

Vital Role ◽

Climatic Conditions ◽

Time Dependent ◽

Railway Infrastructure ◽

Time Dependent Behaviour ◽

The Impact ◽

Dependent Behaviour

Railway networks are exposed to various environmental conditions. It is thus critical that infrastructure components can tolerate such effects by design. Railway sleepers are a critical safety component in ballasted track systems. Prestressed concrete is currently the most common material for railway sleepers due to its superior advantages in structural performance, low maintenance, sustainability, and construction. In practice, many prestressed concrete sleepers are installed in harsh environments that are subject to various changes in climate. Environmental conditions are, therefore, one of the most critical phenomena affecting the time-dependent behaviour of prestressed concrete sleepers. Hence, the impact of climate changes on the serviceability of railway infrastructure needs to be thoroughly investigated. Temperature and relative humidity are crucial aspects that have not been sufficiently studied so far with reference to prestressed concrete sleepers embedded in track systems. This study aims to investigate the effects of extreme climatic conditions on the performance and time-dependent behaviour of prestressed concrete sleepers using contemporary design approaches. The issue concerning the effects of climate uncertainties on creep and shrinkage is rigorously investigated on the basis of both environmental temperature and relative humidity. The outcome indicates that environmental conditions play a vital role in the time-dependent behaviour of prestressed concrete sleepers. The insights will be essential for assessing the long-term serviceability of prestressed concrete sleepers that have been installed in railway lines and are subjected to extreme environmental conditions.

Microbial community networks across body sites are associated with susceptibility to respiratory infections in infants

Communications Biology ◽

10.1038/s42003-021-02755-1 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Marta Reyman ◽

Melanie Clerc ◽

Marlies A. van Houten ◽

Kayleigh Arp ◽

Mei Ling J. N. Chu ◽

...

Keyword(s):

Respiratory Tract ◽

Microbial Communities ◽

Respiratory Tract Infections ◽

Respiratory Infections ◽

Respiratory Health ◽

Strong Association ◽

Sequencing Data ◽

Microbial Network ◽

Tract Infections ◽

AbstractRespiratory tract infections are a major cause of morbidity and mortality worldwide in young children. Concepts such as the gut-lung axis have highlighted the impact of microbial communities at distal sites in mediating disease locally. However, little is known about the extent to which microbial communities from multiple body sites are linked, and how this relates to disease susceptibility. Here, we combine 16S-based rRNA sequencing data from 112 healthy, term born infants, spanning three body sites (oral cavity, nasopharynx, gut) and the first six months of life. Using a cross-niche microbial network approach, we show that, already from the first week of life on, there is a strong association between both network structure and species essential to these structures (hub species), and consecutive susceptibility to respiratory tract infections in this cohort. Our findings underline the crucial role of cross-niche microbial connections in respiratory health.

Studying the Impact of Different Field Environmental Conditions on Seed Quality of Quinoa: The Case of Three Different Years Changing Seed Nutritional Traits in Southern Europe

Frontiers in Plant Science ◽

10.3389/fpls.2021.649132 ◽

2021 ◽

Vol 12 ◽

Author(s):

Sara Granado-Rodríguez ◽

Nieves Aparicio ◽

Javier Matías ◽

Luis Felipe Pérez-Romero ◽

Isaac Maestro ◽

...

Keyword(s):

Antioxidant Capacity ◽

Seed Quality ◽

Chenopodium Quinoa ◽

Climatic Conditions ◽

Southern Europe ◽

Nutritional Properties ◽

The Impact ◽

Shed Light

Chenopodium quinoa Willd (quinoa) has acquired an increased agronomical and nutritional relevance due to the capacity of adaptation to different environments and the exceptional nutritional properties of their seeds. These include high mineral and protein contents, a balanced amino acid composition, an elevated antioxidant capacity related to the high phenol content, and the absence of gluten. Although it is known that these properties can be determined by the environment, limited efforts have been made to determine the exact changes occurring at a nutritional level under changing environmental conditions in this crop. To shed light on this, this study aimed at characterizing variations in nutritional-related parameters associated with the year of cultivation and different genotypes. Various nutritional and physiological traits were analyzed in seeds of different quinoa cultivars grown in the field during three consecutive years. We found differences among cultivars for most of the nutritional parameters analyzed. It was observed that the year of cultivation was a determinant factor in every parameter studied, being 2018 the year with lower yields, germination rates, and antioxidant capacity, but higher seed weights and seed protein contents. Overall, this work will greatly contribute to increase our knowledge of the impact of the environment and genotype on the nutritional properties of quinoa seeds, especially in areas that share climatic conditions to Southern Europe.