Medical research

Using nanocapsules to deliver vaccines to lungs

Many viruses and bacteria infect humans through mucosal surfaces, such as those in the lungs, gastrointestinal tract and reproductive tract. To help fight these pathogens, scientists are working on vaccines that can establish ...

Diseases, Conditions, Syndromes

Earliest known evidence of 1918 influenza pandemic found

Examination of lung tissue and other autopsy material from 68 American soldiers who died of respiratory infections in 1918 has revealed that the influenza virus that eventually killed 50 million people worldwide was circulating ...

Immunology

Cells sacrifice themselves to boost immune response to viruses

Whether flu or coronavirus, it can take several days for the body to ramp up an effective response to a viral infection. New research appearing in the journal Nature Immunology describes how different cells in the immune ...

Diseases, Conditions, Syndromes

Protective immunity to seasonal coronaviruses may be short-lasting

The duration of protective immunity against SARS-CoV-2 may be short-lived, suggests a study investigating immunity to four other, similar coronaviruses. The findings from a case study of ten healthy subjects monitored over ...

Medical research

Scent-sensing cells have a better way to fight influenza

Influenza researchers have long focused most of their efforts on the epithelial cells lining the lungs because these are the cells that become infected and killed while producing new copies of the virus.

Diseases, Conditions, Syndromes

Nasal vaccine against COVID-19 prevents infection in mice

Scientists at Washington University School of Medicine in St. Louis have developed a vaccine that targets the SARS-CoV-2 virus, can be given in one dose via the nose and is effective in preventing infection in mice susceptible ...

Diseases, Conditions, Syndromes

Airborne viruses can spread on dust, non-respiratory particles

Influenza viruses can spread through the air on dust, fibers and other microscopic particles, according to new research from the University of California, Davis and the Icahn School of Medicine at Mt. Sinai. The findings, ...

Medical research

COVID-19 mouse model will speed search for drugs, vaccines

The global effort to quickly develop drugs and vaccines for COVID-19 has been hampered by limited numbers of laboratory mice that are susceptible to infection with SARS-CoV-2, the virus that causes COVID-19. Now, researchers ...

Diseases, Conditions, Syndromes

Bacteria in pneumonia attack using bleaching agent

Research shows that bacteria use hydrogen peroxide to weaken the immune system and cause pneumonia. This according to a study at UmeƄ University and Stockholm University, Sweden. Hydrogen peroxide is also known as a bleaching ...

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Respiratory tract

In humans the respiratory tract is the part of the anatomy that has to do with the process of respiration.

The respiratory tract is divided into 3 segments:

The respiratory tract is a common site for infections. Upper respiratory tract infections are probably the most common infections in the world.

Most of the respiratory tract exists merely as a piping system for air to travel in the lungs; alveoli are the only part of the lung that exchanges oxygen and carbon dioxide with the blood.

Moving down the respiratory tract starting at the trachea, the tubes get smaller and divide more and more. There are estimated to be about 20 to 23 divisions, ending up at an alveolus.

Even though the cross-sectional area of each bronchus or bronchiole is smaller, because there are so many, the total surface area is larger. This means there is less resistance at the terminal bronchioles. (Most resistance is around the 3-4 division from the trachea due to turbulence.)

This text uses material from Wikipedia, licensed under CC BY-SA