درباره محیط کشت آگار مک کانکی

یکی از انواع محیط های کشت در آزمایشگاه میکروبیولوژی محیط کشت مک کانکی می باشد.که مطلب آن را در ادامه مطلب گذاشته ام.

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روش انجام تست کاتالاز در آزمایشگاه

Catalase Test

Catalase is the enzyme that breaks hydrogen peroxide (H2O2) into H2O and O2. Hydrogen peroxide is often used as a topical disinfectant in wounds, and the bubbling that is seen is due to the evolution of O2 gas. H2O2 is a potent oxidizing agent that can wreak havoc in a cell; because of this, any cell that uses O2 or can live in the presence of O2 must have a way to get rid of the peroxide. One of those ways is to make catalase.

You can find the test protocol here.

 

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East Coast Fever _ Theileria parva

East Coast Fever _ Theileria parva

Introduction

Bovine theileriosis is a tick-borne protozoal disease caused by six species of Theileria. Two of these species, Theileria parva and Theileria annulata, are pathogenic and responsible for significant economic and production losses in affected ungulates. T. parva, the causative agent of East Coast fever, occurs in Africa between southern Sudan, South Africa, and Zaire. T. parva can infect cattle, Indian water buffalo, African buffalo and waterbucks, however cattle and Indian water buffalo are the only species that develop symptomatic infections. Those breeds not native to areas where East Coast fever occurs are particularly susceptible.

Life Cycle and Transmission

The primary vector for East Coast fever is Rhipicephalus appendiculatus but R. zembeziensis and R. duttoni also are capable of transmitting the disease. Protozoal sporozoites are produced in the salivary glands of nymph or adult ticks, and subsequently inoculated into a susceptible animal during feeding. Typically, a tick must be attached for 48-72 hours before it transmits the sporozoites. However, if environmental temperatures are high, the organism can be transmitted in only a few hours. Once inside the host, the organisms target lymphocytes. Schizonts may be found in regional lymph nodes within 5-8 days after inoculation. The schizont, also referred to as a macroschizont or Koch’s blue body, causes blast-transformation of the infected lymphocyte (Figure 1) which produces two daughter cells, each of which contains a schizont. Every 3 days, the number of schizonts increases ten-fold. Approximately 10-25 days post-infection (average 14 days), schizonts develop into merozoites which are also known as microschizonts. These merozoites are initially found in the cytoplasm of lymphocytes, reticular cells, and macrophages. They subsequently invade erythrocytes where they become piroplasms. The piroplasm-containing erythrocytes are ingested by larval or nymphal ticks during feeding. Once inside the gut of the tick, the protozoa undergo a sexual cycle which results in the formation of a motile stage of the organism which allows it to reach the salivary glands of the tick so the entire life cycle can begin

applied microbiology

Medical microbiology: The study of the pathogenic microbes and the role of microbes in human illness. Includes the study of microbial pathogenesis and epidemiology and is related to the study of disease pathology and immunology.

Pharmaceutical microbiology: The study of microorganisms that are related to the production of antibiotics, enzymes, vitamins,vaccines, and other pharmaceutical products and that cause pharmaceutical contamination and spoil.

Industrial microbiology: The exploitation of microbes for use in industrial processes. Examples include industrial fermentation and wastewater treatment. Closely linked to the biotechnology industry. This field also includes brewing, an important application of microbiolog

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modern microbiology

In 1676, Antonie van Leeuwenhoek observed bacteria and other microorganisms, using a single-lens microscope of his own design.^[1] While Van Leeuwenhoek is often cited as the first to observe microbes, Robert Hooke made the first recorded microscopic observation, of the fruiting bodies of molds, in 1665.^[8] The first observation of microbes using a microscope is generally credited to the Dutch draper and haberdasher, Antonie van Leeuwenhoek, who lived for most of his life in Delft, Holland. It has, however, been suggested that a Jesuit priest called Athanasius Kircher was the first to observe micro-organisms.^[9] He was among the first to design magic lanterns for projection purposes, so he must have been well acquainted with the properties of lenses.^[9] One of his book contains a chapter in Latin, which reads in translation – ‘Concerning the wonderful structure of things in nature, investigated by Microscope. Here, he wrote ‘who would believe that vinegar and milk abound with an innumerable multitude of worms.’ He also

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a brief story about microbiology

1546: Hieronymus Fracastorius (Girolamo Fracastoro) wrote "On Contagion" ("De contagione et contagiosis morbis et curatione"), the the first known discussion of the phenomenon of contagious infection.

1835 Agostino Bassi de Lodi showed that a disease affecting silkworms was caused by a fungus - the first microorganism to be recognized as a contagious agent of animal disease.

1847: Ignaz Semmelweiss (1818-1865), a Hungarian physician who decided that doctors in Vienna hospitals were spreading childbed fever while delivering babies. He started forcing doctors under his supervision to wash their hands before touching patients.

1857: Louis Pasteur proposed the "germ theory" of disease.

1867: Joseph Lister (1827-1912) introduced antiseptics in surgery. By spraying carbolic acid on surgical instruments, wounds and dressings, he reduced surgical mortality due to bacterial infection considerably.

1876: Robert Koch (1843-1910). German bacteriologist was the first to cultivate anthrax bacteria outside the body using blood serum at body temperature. Building on pasteur's "germ theory", he subsequently published "Koch's postulates" (1884), the critical test for the involvement of a microorganism in a disease:

1. The agent must be present in every case of the disease.
2. The agent must be isolated and cultured in vitro.
3. The disease must be reproduced when a pure culture of the agent is inoculated into a susceptible host.
4. The agent must be recoverable from the experimentally-infected host.

This eventually led to:

• Development of pure culture techniques

Stains, agar, culture media, petri

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