Atto Tigri was an Italian anatomist born in Pistoia

Pistoia

Pistoia is a city and comune in the Tuscany region of Italy, the capital of a province of the same name, located about 30 km west and north of Florence and is crossed by the Ombrone Pistoiese, a tributary of the River Arno.-History:...

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He studied medicine in Pistoia

Pistoia

Pistoia is a city and comune in the Tuscany region of Italy, the capital of a province of the same name, located about 30 km west and north of Florence and is crossed by the Ombrone Pistoiese, a tributary of the River Arno.-History:...

 and at the University of Pisa

University of Pisa

The University of Pisa , located in Pisa, Tuscany, is one of the oldest universities in Italy. It was formally founded on September 3, 1343 by an edict of Pope Clement VI, although there had been lectures on law in Pisa since the 11th century...

, where he became an assistant to Filippo Civinini

Filippo Civinini

Filippo Civinini was an Italian anatomist from Pistoia. He is remembered for contributions made in the field of osteology, in particular the cranium....

 (1805-1844). Later he was a professor of human and comparative anatomy

Comparative anatomy

Comparative anatomy is the study of similarities and differences in the anatomy of organisms. It is closely related to evolutionary biology and phylogeny .-Description:...

 at the University of Siena

University of Siena

The University of Siena in Siena, Tuscany is one of the oldest and first publicly funded universities in Italy. Originally called Studium Senese, the University of Siena was founded in 1240. The University has around 20,000 students, nearly half of Siena's total population of around 54,000...

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In the late 1840s, Tigri is credited for providing the first comprehensive description of the reticular tissue

Tissue (biology)

Tissue is a cellular organizational level intermediate between cells and a complete organism. A tissue is an ensemble of cells, not necessarily identical, but from the same origin, that together carry out a specific function. These are called tissues because of their identical functioning...

 of the spleen

Spleen

The spleen is an organ found in virtually all vertebrate animals with important roles in regard to red blood cells and the immune system. In humans, it is located in the left upper quadrant of the abdomen. It removes old red blood cells and holds a reserve of blood in case of hemorrhagic shock...

, which he called trama microscopica. He also did extensive research on the circulation of blood

Blood

Blood is a specialized bodily fluid in animals that delivers necessary substances such as nutrients and oxygen to the cells and transports metabolic waste products away from those same cells....

 in the spleen. In a treatise titled Nuova Disposizione dell' Apparecchio Vascolare Sanguigno della Milza Umana, he provided an early discussion of tuberculosis

Tuberculosis

Tuberculosis, MTB, or TB is a common, and in many cases lethal, infectious disease caused by various strains of mycobacteria, usually Mycobacterium tuberculosis. Tuberculosis usually attacks the lungs but can also affect other parts of the body...

 and vibrio cholerae

Vibrio cholerae

Vibrio cholerae is a Gram-negative, comma-shaped bacterium. Some strains of V. cholerae cause the disease cholera. V. cholerae is facultatively anaerobic and has a flagella at one cell pole. V...

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Selected writings

• Della Funzione della Milza (1849)
• Nuova Disposizione dell' Apparecchio Vascolare Sanguigno della Milza Umana (1847)