What microorganism did Alexandre Yersin discover?
the plague bacillus
Swiss-born Alexandre Yersin joined the Institut Pasteur in 1885 aged just 22 and worked under Émile Roux. He discovered the plague bacillus in Hong Kong. A brilliant scientist, he was also an explorer and pioneer in many fields.
Who discovered plague virus?
The causative bacterium of plague was described and cultured by Alexandre Yersin in Hong Kong in 1894, after which transmission of bacteria from rodents by flea bites was discovered by Jean-Paul Simond in 1898.
Who discovered plague vaccine?
The idea to develop vaccine against plague started by Alexandre Yersin in 1895 who investigated immunity against Y. pestis in small animal models in his laboratory.
Who is known as father of immunology?
Louis Pasteur is traditionally considered as the progenitor of modern immunology because of his studies in the late nineteenth century that popularized the germ theory of disease, and that introduced the hope that all infectious diseases could be prevented by prophylactic vaccination, as well as also treated by …
Who made BCG vaccine?
2012 – 91 years of BCG vaccination. In 1900 Albert Calmette and Camille Guérin began their research for an antituberculosis vaccine at the Pasteur Institute in Lille. They cultivated tubercle bacilli on a glycerin and potato medium but found it difficult to produce a homogeneous suspension of the bacilli.
What is the Chvostek sign?
The Chvostek sign is a clinical finding associated with hypocalcemia, or low levels of calcium in the blood. This clinical sign refers to a twitch of the facial muscles that occurs when gently tapping an individual’s cheek, in front of the ear.
Is Chvostek’s sign found in tetany?
Chvostek’s sign is found in tetany. However, it may also be present in hypomagnesemia. Magnesium is a cofactor for adenylate cyclase, which catalyzes the conversion of ATP to 3′,5′-cyclic AMP.
What did Chvostek do in his life?
In his professional life, Chvostek devoted himself to the study of etiopathogenesis and to the treatment of neurological disorders, including by means of electrotherapy. In 1876, he first described the sign that bears his name. Later it was independently described by another Austrian physician, Nathan Weiss (1851–1883), in 1883.
What does a positive Chvostek test result mean?
A positive Chvostek sign mainly indicates that the individual’s calcium levels are low. Maintaining stable calcium levels is necessary for regulating the function of many cellular processes, including neuronal activity, muscular contraction, hormone secretion, and blood coagulation (i.e., process of blood clot formation ).