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Rebecca Lancefield
Rebecca Craighill Lancefield (January 5, 1895 – March 3, 1981). p.227 was a prominent American microbiologist. She joined the Rockefeller Institute for Medical Research (now Rockefeller University) in New York in 1918, and was associated with that institute throughout her long and outstanding career. Her bibliography comprises more than 50 publications published over 60 years. Lancefield is best known for her serological classification of β-hemolytic streptococcal bacteria, Lancefield grouping, which is based on the carbohydrate composition of bacterial antigens found on their cell walls. She is also responsible for the serological typing of Group A Streptococci. Early life and education Lancefield was born at Fort Wadsworth, Staten Island, New York. Her father was an officer in the US Army Engineer Corps. She attended Wellesley College in Massachusetts. After graduating in 1916 with a degree in zoology, she taught math and science at a girls school in Vermont for one y ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacteriology
Bacteriology is the branch and specialty of biology that studies the morphology, ecology, genetics and biochemistry of bacteria as well as many other aspects related to them. This subdivision of microbiology involves the identification, classification, and characterization of bacterial species. Because of the similarity of thinking and working with microorganisms other than bacteria, such as protozoa, fungi, and viruses, there has been a tendency for the field of bacteriology to extend as microbiology. The terms were formerly often used interchangeably. However, bacteriology can be classified as a distinct science. Overview Definition Bacteriology is the study of bacteria and their relation to medicine. Bacteriology evolved from physicians needing to apply the germ theory to address the concerns relating to disease spreading in hospitals the 19th century. Identification and characterizing of bacteria being associated to diseases led to advances in pathogenic bacteriology. K ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antigen
In immunology, an antigen (Ag) is a molecule or molecular structure or any foreign particulate matter or a pollen grain that can bind to a specific antibody or T-cell receptor. The presence of antigens in the body may trigger an immune response. The term ''antigen'' originally referred to a substance that is an antibody generator. Antigens can be proteins, peptides (amino acid chains), polysaccharides (chains of monosaccharides/simple sugars), lipids, or nucleic acids. Antigens are recognized by antigen receptors, including antibodies and T-cell receptors. Diverse antigen receptors are made by cells of the immune system so that each cell has a specificity for a single antigen. Upon exposure to an antigen, only the lymphocytes that recognize that antigen are activated and expanded, a process known as clonal selection. In most cases, an antibody can only react to and bind one specific antigen; in some instances, however, antibodies may cross-react and bind more than one antigen. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maclyn McCarty
Maclyn McCarty (June 9, 1911 – January 2, 2005) was an American geneticist, a research scientist described in 2005 as "the last surviving member of a Manhattan scientific team that overturned medical dogma in the 1940's and became the first to demonstrate that genes were made of DNA." He had worked at Rockefeller University "for more than 60 years." 1994 marked 50 years since this work's release. McCarty devoted his life as a physician-scientist to studying infectious disease organisms, and was best known for his part in the monumental discovery that DNA, rather than protein, constituted the chemical nature of a gene. Uncovering the molecular secret of the gene in question — that for the capsular polysaccharide of pneumococcal bacteria — led the way to studying heredity not only through genetics but also through chemistry. The team responsible for this feat is known as the Avery–MacLeod–McCarty experiment. He died from congestive heart failure. Early life McCarty was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing military alliances: the Allies and the Axis powers. World War II was a total war that directly involved more than 100 million personnel from more than 30 countries. The major participants in the war threw their entire economic, industrial, and scientific capabilities behind the war effort, blurring the distinction between civilian and military resources. Aircraft played a major role in the conflict, enabling the strategic bombing of population centres and deploying the only two nuclear weapons ever used in war. World War II was by far the deadliest conflict in human history; it resulted in 70 to 85 million fatalities, mostly among civilians. Tens of millions died due to genocides (including the Holocaust), starvation, ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Group B Streptococcal Infection
Group B streptococcal infection, also known as Group B streptococcal disease or just Group B strep, is the infection caused by the bacterium ''Streptococcus agalactiae'' (''S. agalactiae'') (also known as group B streptococcus or GBS). GBS infection can cause serious illness and sometimes death, especially in newborns, the elderly, and people with compromised immune systems. As other virulent bacteria, GBS harbours an important number of virulence factors, The most important are the capsular polysaccharide (rich in sialic acid), and a pore-forming toxin, β-haemolysin. The GBS capsule is probably the key virulence factor because it helps GBS escape from the host defence mechanisms interfering with phagocytic killing of GBS by human phagocytes. The GBS β-haemolysin is considered almost identical to the GBS pigment (granadaene). GBS was recognized as a pathogen in cattle by Edmond Nocard and Mollereau in the late 1880s. It can cause bovine mastitis (inflammation of the udder) in d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Group A Streptococcal Infection
Group A streptococcal infections are a number of infections with ''Streptococcus pyogenes'' a group A streptococcus (GAS). ''S. pyogenes'' is a species of beta-hemolytic gram-positive bacteria that is responsible for a wide range of infections that are mostly common and fairly mild. If the bacteria enter the bloodstream an infection can become severe and life-threatening, and is called an invasive GAS (iGAS). Infection of GAS may spread through direct contact with mucus or sores on the skin. GAS infections can cause over 500,000 deaths per year. Despite the emergence of antibiotics as a treatment for group A streptococcus, cases of iGAS are an increasing problem, particularly on the continent of Africa. There are many other species of ''Streptococcus'', including Group B streptococcus ''Streptococcus agalactiae'', and ''Streptococcus pneumoniae'', which cause other types of infections. Several virulence factors contribute to the pathogenesis of GAS, such as M protein, hemolysins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
M Protein (Streptococcus)
M protein is a virulence factor that can be produced by certain species of ''Streptococcus''. Viruses, parasites and bacteria are covered in protein and sugar molecules that help them gain entry into a host by counteracting the host's defenses. One such molecule is the M protein produced by certain streptococcal bacteria. At its C-terminus within the cell wall, M proteins embody a motif that is now known to be shared by many Gram-positive bacterial surface proteins. The motif includes a conserved pentapeptide LPXTG, which precedes a hydrophobic C-terminal membrane spanning domain, which itself precedes a cluster of basic residues at the C-terminus. M protein is strongly anti-phagocytic and is the major virulence factor for group A streptococci (''Streptococcus pyogenes''). It binds to serum factor H, destroying C3-convertase and preventing opsonization by C3b. However plasma B cells can generate antibodies against M protein which will help in opsonization and further the d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rheumatic Fever
Rheumatic fever (RF) is an inflammatory disease that can involve the heart, joints, skin, and brain. The disease typically develops two to four weeks after a streptococcal throat infection. Signs and symptoms include fever, multiple painful joints, involuntary muscle movements, and occasionally a characteristic non-itchy rash known as erythema marginatum. The heart is involved in about half of the cases. Damage to the heart valves, known as rheumatic heart disease (RHD), usually occurs after repeated attacks but can sometimes occur after one. The damaged valves may result in heart failure, atrial fibrillation and infection of the valves. Rheumatic fever may occur following an infection of the throat by the bacterium ''Streptococcus pyogenes''. If the infection is left untreated, rheumatic fever occurs in up to three percent of people. The underlying mechanism is believed to involve the production of antibodies against a person's own tissues. Due to their genetics, some peo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viridans Streptococci
The viridans streptococci are a large group of commensal streptococcal Gram-positive bacteria species that are α-hemolytic, producing a green coloration on blood agar plates (hence the name "viridans", from Latin "vĭrĭdis", green), although some species in this group are actually γ-hemolytic, meaning they produce no change on blood agar. The pseudo-taxonomic term "Streptococcus viridans" is often used to refer to this group of species, but writers who do not like to use the pseudotaxonomic term (which treats a group of species as if they were one species) prefer the terms viridans streptococci,Dorland's Illustrated Medical Dictionary, headword "streptococcus", subentry "viridans streptococci". viridans group streptococci (VGS), or viridans streptococcal species. These species possess no Lancefield antigens. In general, pathogenicity is low. Identification Viridans streptococci can be differentiated from ''Streptococcus pneumoniae'' using an optochin test, as viridans strepto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drosophila Willistoni
''Drosophila willistoni'' is a species of fruit fly. It was originally described by Alfred Sturtevant in 1916. It ranges from Florida, Mexico and Caribbean islands southwards to Argentina and is the most common Drosophilid fruit fly in the Amazon rainforest The Amazon rainforest, Amazon jungle or ; es, Selva amazónica, , or usually ; french: Forêt amazonienne; nl, Amazoneregenwoud. In English, the names are sometimes capitalized further, as Amazon Rainforest, Amazon Forest, or Amazon Jungle. .... This fruitfly is widely used for scientific research, including genetic research. References External links ''Drosophila willistoni'' at FlyBase''Drosophila willistoni'' at Ensembl Genomes Metazoa willistoni Insects described in 1916 Diptera of North America Diptera of South America Insects of the Caribbean {{Drosophilidae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoology
Zoology ()The pronunciation of zoology as is usually regarded as nonstandard, though it is not uncommon. is the branch of biology that studies the Animal, animal kingdom, including the anatomy, structure, embryology, evolution, Biological classification, classification, Ethology, habits, and distribution of all animals, both living and extinction, extinct, and how they interact with their ecosystems. The term is derived from Ancient Greek , ('animal'), and , ('knowledge', 'study'). Although humans have always been interested in the natural history of the animals they saw around them, and made use of this knowledge to domesticate certain species, the formal study of zoology can be said to have originated with Aristotle. He viewed animals as living organisms, studied their structure and development, and considered their adaptations to their surroundings and the function of their parts. The Greek physician Galen studied human anatomy and was one of the greatest surgeons of the a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New York (state)
New York, officially the State of New York, is a state in the Northeastern United States. It is often called New York State to distinguish it from its largest city, New York City. With a total area of , New York is the 27th-largest U.S. state by area. With 20.2 million people, it is the fourth-most-populous state in the United States as of 2021, with approximately 44% living in New York City, including 25% of the state's population within Brooklyn and Queens, and another 15% on the remainder of Long Island, the most populous island in the United States. The state is bordered by New Jersey and Pennsylvania to the south, and Connecticut, Massachusetts, and Vermont to the east; it has a maritime border with Rhode Island, east of Long Island, as well as an international border with the Canadian provinces of Quebec to the north and Ontario to the northwest. New York City (NYC) is the most populous city in the United States, and around two-thirds of the state's popul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
