Prevalence of Bacterial Infections in Respiratory Tract
K. Balamurugan, U. Prithika in Pocket Guide to Bacterial Infections, 2019
The respiratory tract is mainly responsible for breathing. It is distributed into two major portions, the upper respiratory tract (URT) and the lower respiratory tract (LRT). URT comprises of various organs such as sinuses, nasal cavity, pharynx, and larynx; LRT comprises of trachea, bronchi, lungs, and diaphragm (Figure 3.1). The foremost function of the human respiratory system is to passage the inhaled air into lungs and to aid the diffusion of oxygen molecules into the bloodstream. Respiratory tract infections (RTIs) represent a common major health problem and also the most frequently reported infections throughout the world because of their ease of transmission, occurrence, and considerable mortality and morbidity by affecting people of all ages. Traditionally, they are divided into two classes: lower respiratory tract infections (LRTIs) and upper respiratory tract infections (URTIs). Generally, bacterial infections may affect the lower or upper respiratory tract and the pathogens causing these symptoms have a tendency to localize to one region. Some of these RTIs are mild (acute), some are chronic (long-lasting), and sometimes some are self-limiting (Richter et al. 2016). The respiratory tract can be infected by various pathogenic bacteria, both gram-positive and -negative (Felmingham and Gruneberg 2000). But by chance, most of these infections can be treated by well-known antibiotic therapies.
Community and environment as determinants of health
Ben Y.F. Fong, Martin C.S. Wong in The Routledge Handbook of Public Health and the Community, 2021
Ground-level ozone ([O3]) is produced by volatile organic compounds (VOCs, ozone precursors) and nitrogen oxides (NOx) via photochemical reaction under sunlight. It is also one of the important greenhouse gases causing global warming. The sources of VOCs are mainly from solvent-based paints, printing inks, organic solvents and petroleum products. The source of NOx is mostly from factories and fossil fuel burning. The combined effect of ozone with small air pollutants particles causing smog in sunny days. Smog reduces visibility. It is hazardous to human health as it irritates our eyes, nose and respiratory tract. It triggers an asthmatic or COPD attack and is associated with increased respiratory mortality.
Renal, Cardiovascular, and Pulmonary Functions of Dopamine
Nira Ben-Jonathan in Dopamine, 2020
Respiration is the movement of oxygen from the outside environment to the cells within tissues throughout the body, and the transport of carbon dioxide in the opposite direction. As shown in Figure 7.8, the respiratory tract is divided into two main components: the upper respiratory tract, which includes the nasal and oral cavities, pharynx and larynx, and the lower respiratory tract, which includes the trachea, primary bronchi and lungs. Air is breathed in through the nose or the mouth. A mucous membrane within the nasal cavity acts as a filter and traps pollutants and other harmful substances found in the air. From there, air moves into the pharynx, a passage in the intersection between the esophagus and larynx. A flap of cartilage, the epiglottis, allows air to pass through and the same time closes the opening of the esophagus to prevent food from moving into the airway.
Inhibitors of type II transmembrane serine proteases in the treatment of diseases of the respiratory tract – A review of patent literature
Published in Expert Opinion on Therapeutic Patents, 2020
Alexandre Murza, Sébastien P. Dion, Pierre-Luc Boudreault, Antoine Désilets, Richard Leduc, Éric Marsault
TTSP expression is widely spread across the human body, being enriched in epithelial tissues of various origins [2,5]. The respiratory tract, where airflow from the nasal cavity to the lungs enables respiration, can be divided in two main compartments, i.e. the upper respiratory tract (from nasal cavity to larynx) and the lower respiratory tract (trachea and lungs). According to the GTEx RNA-seq database [21], three TTSPs: HPN (hepsin), TMPRSS2, and ST14 (matriptase) are expressed at high levels in healthy human lungs, while TMPRSS3 and TMPRSS13 are expressed at lower levels, in agreement with several publications Figure 1B [22–26]. Furthermore, other reports show low expression of TMPRSS11E (DESC1) in the lungs [27] and predominant expression of TMPRSS11D (HAT, human airway trypsin) and TMPRSS11A (HATL1, human airway trypsin like 1) in the human trachea [28,29]. Finally, both TMPRSS4 and ST14 were also found to be overexpressed in lungs affected by idiopathic pulmonary fibrosis (IPF) [30,31]. These nine TTSPs are thus expressed at different levels in the human airway in normal and/or pathological contexts. For some, their biological role in the lung needs to be better defined, yet their involvement as determinants of respiratory viral infection [32,33], respiratory system-associated diseases, and other pathologies [2,34,35] makes them attractive therapeutic targets.
Can the immunological system of the upper respiratory tract, improved by physical exercise, act as a first immunological barrier against SARS-CoV-2?
Published in Expert Review of Anti-infective Therapy, 2022
Jairo Azócar-Gallardo, Alex Ojeda-Aravena, Jorge Carrizo Largo, Claudio Hernández-Mosqueira
In anatomical terms, the respiratory tract is divided into two segments: upper (nose, nasal cavity, mouth, pharynx, and larynx) and lower (trachea, lungs, and bronchi) [21]. The upper respiratory tract, in particular, is the main site of attacks by invasive microorganisms such as viruses and bacteria, causing upper respiratory tract infections such as acute bronchitis, common cold, influenza, and respiratory distress syndromes [22–24]. To defend itself, the upper respiratory tract releases lymphocytes (B cells) which in turn allow the synthesis of immunoglobulins – specialized antibodies for the humoral immune response to toxins and extracellular pathogens [25,26]. The immunoglobulin family consists basically of three types: immunoglobulin A (IgA; IgA1 and IgA2), immunoglobulin G (IgG), and immunoglobulin M (IgM). They act by inhibiting microorganisms from adhering to the mucosa, thus neutralizing the virus [27,28]. IgA is the predominant antibody, secreted by the mucosas of the organism including nasal and pulmonary secretions, saliva, tears, milk and secretions of the urogenital and intestinal tracts; it is a fundamental ‘first line of defense’ against the vast majority of infections that try to invade the respiratory tract of the human body [23,25,26,29]. Therefore, IgA is an important resistance effector against the pathogenic micro-organisms that cause upper respiratory tract infections [23,25,30,31]; it also acts as a bridge between innate and adaptive immunity [17].
Neurological manifestations of COVID-19: a systematic review and detailed comprehension
Published in International Journal of Neuroscience, 2023
Zeina Hassan Ousseiran, Youssef Fares, Wafaa Takash Chamoun
COVID-19 transmission can occur by either direct mode from covid-19 positive human to human transmission through respiratory droplets or indirect mode from contaminated surfaces and objects and airborne contagions to humans [5]. Disease presentation ranges from asymptomatic (in rare cases) to severe pneumonia and death [6]. The symptoms of this pandemic disease range from mild to moderate in most cases, and sometimes severe with high death risk especially in elderly people and those suffering from chronic diseases such as cancer, diabetes, hypertension, chronic obstructive pulmonary diseases and others. The most common symptoms identified include lower respiratory tract infection, pneumonia, dry cough, fever, shortness of breath and myalgia; other symptoms may occur but less frequently reported including confusion, sore throat, hemoptysis, runny nose, chills, chest pain, rhinorrhea, and diarrhea with nausea and vomiting [4].