Eustachian tube

Examples of Eustachian tube in the following topics:

• Otitis Media

  • It occurs in the area between the tympanic membrane and the inner ear, also effecting a duct known as the eustachian tube.
  • A major risk factor for developing otitis media is Eustachian tube dysfunction, which leads to the ineffective clearing of bacteria from the middle ear.

• Classification and Identification of Helminths

  • The classification and identification of helminths are dependent on numerous factors including body shape, body cavity, body covering, digestive tubing, sex and type of attachment organs.
  • Tapeworms lack a digestive tube and are hermaphroditic.
  • However, the digestive tube for trematodes ends in the cecum.
  • Its body covering is a cuticle and the digestive tube ends in the anus.

• Hydrothermal Vent Microbial Ecosystems

  • Snails, shrimp crabs, tube worms, and fish feed on the bacterial mat and attract larger organisms such as squid and octopuses.
  • For example, the Pompeii tube worm Alvinella pompejana can resist temperatures up to 176°F.
  • Some species of tube worms are specially adapted to withstand the high temperatures found at hydrothermal vents.

• Tissue Culture of Animal Viruses

  • The cell suspension is then placed in a flat-bottomed glass or plastic container (petri dish, a flask, a bottle, test tube) together with a suitable liquid medium. e.g.
  • The inoculated tubes should be incubated at 35-37oC in a rotating drum.
  • If stationary tubes are used, it is critical that the culture tubes be positioned so that the cell monolayer is bathed in nutrient medium.

• Oxygen

  • Aerobically different bacteria behave differently when grown in liquid culture: 1) Obligate aerobic bacteria gather at the top of the test tube in order to absorb maximal amount of oxygen. 2) Obligate anaerobic bacteria gather at the bottom to avoid oxygen. 3) Facultative bacteria gather mostly at the top, since aerobic respiration is advantageous (ie, energetically favorable); but as lack of oxygen does not hurt them, they can be found all along the test tube. 4) Microaerophiles gather at the upper part of the test tube but not at the top.
  • They require oxygen, but at a lower concentration. 5) Aerotolerant bacteria are not affected at all by oxygen, and they are evenly spread along the test tube.

• Detecting Acid and Gas Production

  • The Durham tube method is used to detect production of gas by microorganisms.
  • They are simply smaller test tubes inserted upside down in another test tube.
  • This small tube is initially filled with the solution in which the microorganism is to be grown.
  • If gas is produced after inoculation and incubation, a visible gas bubble will be trapped inside the small tube.
  • The initial air gap produced when the tube is inserted upside down is lost during sterilization , usually performed at 121°C for 15 or so minutes

• Compromised Host

  • Invasive devices, for instance intubation tubes, catheters, surgical drains, and tracheostomy tubes all bypass the body's natural lines of defense against pathogens and provide an easy route for infection .

• Agrobacterium and Crown Gall Disease

  • Typically bacteria transfer plasmids through conjugation: a donor bacteria creates a tube called a pilus that penetrates the cell wall of the recipient bacteria and the plasmid DNA passes through the tube.

• Pure Culture

  • (A) Original culture tubes of Sabouraud agar supplemented with nine antibiotics and incubated at 4°C for six- or eight-weeks; notice the profuse growth of G. destructans strains.
  • (B) Some fungal contamination on individual isolates was visible as depicted in the close-up of a culture tube.

• Specimen Collection

  • Serum is transferred to tightly-closing plastic tubes and stored at 2 – 8°C before shipment--which should always be prompt.
  • This should be transported in tightly-closing plastic tubes.