Hospital therapy. Pathogenesis of bronchial asthma (BA) (most important)

Lecture notes, cheat sheets
Free library / Directory / Lecture notes, cheat sheets

Hospital therapy. Pathogenesis of bronchial asthma (BA) (most important)

Lecture notes, cheat sheets

Table of contents (expand)

22. Pathogenesis of bronchial asthma (BA)

Pathogenesis. Altered bronchial reactivity is the central link in the pathogenesis of the disease and can be primary and secondary. In the first case, the change in reactivity is congenital and acquired. Secondary changes in bronchial reactivity are a manifestation of changes in the reactivity of the immune, endocrine, and nervous systems of the body. Thus, speaking about the pathogenesis of AD, we can distinguish 2 groups of mechanisms: immunological and non-immunological.

Type I (atopic, reaginic, or anaphylactic). In response to the ingestion of exoallergen antigens (pollen, animal and vegetable proteins, bacteria and drugs), an increased production (reagins) occurs, which are fixed and accumulated on mast cells (primary effector cells). This is the immunological stage of AD. Following this, the pathochemical stage of the process develops - degranulation of mast cells with the release of vasoactive, bronchospastic and chemotactic substances (histamine, serotonin, various chemotactic factors, etc.).

Under the influence of biologically active substances, the pathophysiological stage of pathogenesis begins: the permeability of the microcirculatory bed increases, which leads to the development of edema, serous inflammation, and bronchospasm.

Type III reaction (immunocomplex type, or Arthus phenomenon) develops under the influence of exoallergens and endoallergens.

The reaction occurs in the zone of excess antigen with the participation of precipitating antibodies belonging to the immunoglobulins of classes O and M. The damaging effect of the formed antigen-antibody complex is realized through complement activation, the release of lysosomal enzymes.

There is damage to the basal membranes, spasm of smooth muscles of the bronchi, vasodilation, and the permeability of the microvasculature increases.

Type IV (cellular, delayed-type hypersensitivity) is characterized by the fact that sensitized lymphocytes have a damaging effect. In this case, the mediators of the allergic reaction are lymphokines (act on macrophages, epithelial cells), lysosomal enzymes, and an activated kinin system. Under the influence of these substances, edema develops, swelling of the mucous membrane, bronchospasm, hyperproduction of viscous bronchial secretions.

Non-immunological mechanisms are the primary change in bronchial reactivity as a result of congenital and acquired biological defects. Non-immunological mechanisms act on primary or secondary effector cells or on the receptors of the smooth muscles of the bronchi, blood vessels, cells of the bronchial glands. This changes the reactivity of target cells and, above all, mast cells, which is accompanied by excessive production of biologically active substances (histamine, leukotrienes, etc.).

Recently, there has been talk about the special role of glucocorticoid insufficiency and dysovarian disorders in the pathogenesis of bronchial obstruction disorders. Insufficiency of glucocorticosteroids leads to the development of hyperreactivity of mast cells, decreased synthesis of catecholamines, activation of prostaglandins F2a, as well as disruption of the immunocompetent system.

<< Back: Etiology of bronchial asthma (BA)

>> Forward: Classification of bronchial asthma (BA)

We recommend interesting articles Section Lecture notes, cheat sheets:

▪ Latin for doctors. Crib

▪ Advertising. Crib

▪ History of psychology. Crib

See other articles Section Lecture notes, cheat sheets.

Read and write useful comments on this article.

<< Back

Latest news of science and technology, new electronics:

The existence of an entropy rule for quantum entanglement has been proven 09.05.2024

Quantum mechanics continues to amaze us with its mysterious phenomena and unexpected discoveries. Recently, Bartosz Regula from the RIKEN Center for Quantum Computing and Ludovico Lamy from the University of Amsterdam presented a new discovery that concerns quantum entanglement and its relation to entropy. Quantum entanglement plays an important role in modern quantum information science and technology. However, the complexity of its structure makes understanding and managing it challenging. Regulus and Lamy's discovery shows that quantum entanglement follows an entropy rule similar to that for classical systems. This discovery opens new perspectives in the field of quantum information science and technology, deepening our understanding of quantum entanglement and its connection to thermodynamics. The results of the study indicate the possibility of reversibility of entanglement transformations, which could greatly simplify their use in various quantum technologies. Opening a new rule ... >>

Mini air conditioner Sony Reon Pocket 5 09.05.2024

Summer is a time for relaxation and travel, but often the heat can turn this time into an unbearable torment. Meet a new product from Sony - the Reon Pocket 5 mini-air conditioner, which promises to make summer more comfortable for its users. Sony has introduced a unique device - the Reon Pocket 5 mini-conditioner, which provides body cooling on hot days. With it, users can enjoy coolness anytime, anywhere by simply wearing it around their neck. This mini air conditioner is equipped with automatic adjustment of operating modes, as well as temperature and humidity sensors. Thanks to innovative technologies, Reon Pocket 5 adjusts its operation depending on the user's activity and environmental conditions. Users can easily adjust the temperature using a dedicated mobile app connected via Bluetooth. Additionally, specially designed T-shirts and shorts are available for convenience, to which a mini air conditioner can be attached. The device can oh ... >>

Energy from space for Starship 08.05.2024

Producing solar energy in space is becoming more feasible with the advent of new technologies and the development of space programs. The head of the startup Virtus Solis shared his vision of using SpaceX's Starship to create orbital power plants capable of powering the Earth. Startup Virtus Solis has unveiled an ambitious project to create orbital power plants using SpaceX's Starship. This idea could significantly change the field of solar energy production, making it more accessible and cheaper. The core of the startup's plan is to reduce the cost of launching satellites into space using Starship. This technological breakthrough is expected to make solar energy production in space more competitive with traditional energy sources. Virtual Solis plans to build large photovoltaic panels in orbit, using Starship to deliver the necessary equipment. However, one of the key challenges ... >>

Random news from the Archive

Speed sensor VG481V1 13.08.2020

The new VG481V1 sensor from Honeywell is designed to measure the speed of rotation of a ferrous metal gear.

The sensor allows you to detect the fact of the passage of a gear tooth. The moving gear tooth changes the magnetic field created by the bias magnet, which is recorded by the Hall sensor. With dual-peak detection circuitry, the VG481V1 can measure the speed of the gear with high reliability.

The VG481V1 speed sensor is used in automotive transmissions and, in general, is applicable in any transmission and mechanisms where it is necessary to monitor the rotation of a ferrous metal gear.

The VG481V1 includes a voltage regulator, a clock generator, a Hall element, an amplifier, a high and low detection circuit, a comparator, and an output stage. The sensor is protected from abnormal operation at voltages below the minimum threshold, the output of the microcircuit is resistant to short circuits.

The power circuit is insensitive to reverse voltage polarity. When power is applied to the sensor, the trigger circuit does not allow operation until a stable reading is established. VG481V1 allows you to define zero rotation speed.

The sensor is available in a slim size TO-92.

The main parameters of the Hall sensor VG481V1:

Rotation speed measurement;
Zero speed fixing;
Low price and simple inclusion;
Supply voltage from 4 to 24 V;
Operating temperature -40 to 150°C;
Output current up to 20 mA (open collector);
Output short circuit protection;
Reverse polarity protection;
Certified by AEC-Q100 (Grade 0).

Other interesting news:

▪ Stress suppresses fear

▪ Forced braking of cars

▪ AOC Q2781PQ Frameless Monitor

▪ The benefits and harms of video games

▪ Water is divided into two different liquids

News feed of science and technology, new electronics

Interesting materials of the Free Technical Library:

▪ section of the site Aphorisms of famous people. Article selection

▪ article The concept of drifting continents. History and essence of scientific discovery

▪ article Which parasitic tree can cut underground telephone cables? Detailed answer

▪ article Melon pear. Legends, cultivation, methods of application

▪ article Sounding keychain on a single chip. Encyclopedia of radio electronics and electrical engineering

▪ article Directly opposite orders. Focus secret

Leave your comment on this article:

All languages of this page

Home page | Library | Articles | Website map | Site Reviews