|
Histoplasma
''Histoplasma'' is a genus of dimorphic fungi commonly found in bird and bat fecal material. ''Histoplasma'' contains a few species, including—''Histoplasma capsulatum''—the causative agent of histoplasmosis; and ''Histoplasma capsulatum var. farciminosum'' (old term, ''Histoplasma farciminosum''), causing epizootic lymphangitis in horses. This fungus is mainly found in the Ohio and Mississippi River Valleys in the United States as well as Central/South America, Africa, Asia and Australia. Forms / Stages Histoplasma capsulatum has two forms: its environmental form is hyphae with microconidia and tuberculate macroconidia while its tissue form is a small intracellular yeast with a narrow neck and no bud with no capsule and can be detected in aerobic blood culture bottle. In the saprophytic stage, it bears features of both microconidia and macroconidia. Infection occurs through inhalation of the small microconidia or small mycelia fragments. The dimorphic mold-yeast transfo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Histoplasmosis
Histoplasmosis is a fungal infection caused by ''Histoplasma capsulatum''. Symptoms of this infection vary greatly, but the disease affects primarily the lungs. Occasionally, other organs are affected; called disseminated histoplasmosis, it can be fatal if left untreated. Histoplasmosis is common among AIDS patients because of their suppressed immunity. In immunocompetent individuals, past infection results in partial protection against ill effects if reinfected. ''Histoplasma capsulatum'' is found in soil, often associated with decaying bat guano or bird droppings. Disruption of soil from excavation or construction can release infectious elements that are inhaled and settle into the lung. From 1938 to 2013 in the US, 105 outbreaks were reported in a total of 26 states plus Puerto Rico. In 1978 to 1979 during a large urban outbreak in which 100,000 people were exposed to the fungus in Indianapolis, victims had pericarditis, rheumatological syndromes, esophageal and vocal cord ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Histoplasma Duboisii
''Histoplasma duboisii'' is a saprotrophic fungus responsible for the invasive infection known as African histoplasmosis. This species is a close relative of ''Histoplasma capsulatum'', the agent of classical histoplasmosis, and the two occur in similar habitats. ''Histoplasma duboisii'' is restricted to continental Africa and Madagascar, although scattered reports have arisen from other places usually in individuals with an African travel history. Like, ''H. capsulatum'', ''H. duboisii'' is dimorphic – growing as a filamentous fungus at ambient temperature and a yeast at body temperature. It differs morphologically from ''H. capsulatum'' by the typical production of a large-celled yeast form. Both agents cause similar forms of disease, although ''H. duboisii'' predominantly causes cutaneous and subcutaneous disease in humans and non-human primates. The agent responds to many antifungal drug therapies used to treat serious fungal diseases. History Histoplasmosis was first repo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Histoplasma Capsulatum
''Histoplasma capsulatum'' is a species of dimorphic fungus. Its sexual form is called ''Ajellomyces capsulatus''. It can cause pulmonary and disseminated histoplasmosis. ''H. capsulatum'' is "distributed worldwide, except in Antarctica, but most often associated with river valleys" and occurs chiefly in the "Central and Eastern United States" followed by "Central and South America, and other areas of the world". It is most prevalent in the Ohio and Mississippi River valleys. It was discovered by Samuel Taylor Darling in 1906. Growth and morphology ''H. capsulatum'' is an ascomycetous fungus closely related to ''Blastomyces dermatitidis''. It is potentially sexual, and its sexual state, ''Ajellomyces capsulatus'', can readily be produced in culture, though it has not been directly observed in nature. ''H. capsulatum'' groups with ''B. dermatitidis'' and the South American pathogen ''Paracoccidioides brasiliensis'' in the recently recognized fungal family Ajellomycetaceae. It ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PAS Diastase
Periodic acid–Schiff–diastase (PAS-D, PAS diastase) stain is a periodic acid–Schiff (PAS) stain used in combination with diastase, an enzyme that breaks down glycogen. PAS-D is a stain often used by pathologists as an ancillary study in making a histologic diagnosis on paraffin-embedded tissue specimens. PAS stain typically gives a magenta color in the presence of glycogen. When PAS and diastase are used together, a light pink color replaces the deep magenta. Differences in the intensities of the two stains (PAS and PAS-D) can be attributed to different glycogen concentrations and can be used to semiquantify glycogen in samples. In practice, the tissue is deparaffinized, the diastase incubates, and then the PAS stain is applied. An example of PAS-D in use is in showing gastric/duodenal metaplasia in duodenal adenomas. PAS diastase stain is also used to identify alpha-1 antitrypsin globules in hepatocytes, which is a characteristic finding of alpha-1 antitrypsin deficiency ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Samuel Taylor Darling
Samuel Taylor Darling (April 6, 1872 in Harrison, New Jersey – May 21, 1925 in Beirut) was an American pathologist and bacteriologist who discovered the pathogen ''Histoplasma capsulatum'' in Panama in 1906. He died in Beirut in a car accident together with British malariologist Norman Lothian.Irish Journal of Medical Science (1926–1967) Volume 4, Number 12, p. 570 The Darling Foundation prize for malaria Malaria is a mosquito-borne infectious disease that affects humans and other animals. Malaria causes symptoms that typically include fever, tiredness, vomiting, and headaches. In severe cases, it can cause jaundice, seizures, coma, or death. S ... research was established in his memory. References External links A website about Samuel Taylor Darling {{DEFAULTSORT:Darling, Samuel Taylor 1872 births 1925 deaths American bacteriologists American pathologists People from Harrison, New Jersey ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ascomycota
Ascomycota is a phylum of the kingdom Fungi that, together with the Basidiomycota, forms the subkingdom Dikarya. Its members are commonly known as the sac fungi or ascomycetes. It is the largest phylum of Fungi, with over 64,000 species. The defining feature of this fungal group is the " ascus" (), a microscopic sexual structure in which nonmotile spores, called ascospores, are formed. However, some species of the Ascomycota are asexual, meaning that they do not have a sexual cycle and thus do not form asci or ascospores. Familiar examples of sac fungi include morels, truffles, brewers' and bakers' yeast, dead man's fingers, and cup fungi. The fungal symbionts in the majority of lichens (loosely termed "ascolichens") such as ''Cladonia'' belong to the Ascomycota. Ascomycota is a monophyletic group (it contains all descendants of one common ancestor). Previously placed in the Deuteromycota along with asexual species from other fungal taxa, asexual (or anamorphic) ascomyce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ajellomycetaceae
The Ajellomycetaceae are a family of fungi in the Ascomycota, class Eurotiomycetes. The family contains eight genera Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclat .... References Onygenales Ascomycota families Taxa described in 2004 {{Eurotiomycetes-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fungi
A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from the other eukaryotic kingdoms, which by one traditional classification include Plantae, Animalia, Protozoa, and Chromista. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Fungi, like animals, are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related organisms, named the ''Eumycota'' (''t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fungi
A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from the other eukaryotic kingdoms, which by one traditional classification include Plantae, Animalia, Protozoa, and Chromista. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Fungi, like animals, are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related organisms, named the ''Eumycota'' (''t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypha
A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium. Structure A hypha consists of one or more cells surrounded by a tubular cell wall. In most fungi, hyphae are divided into cells by internal cross-walls called "septa" (singular septum). Septa are usually perforated by pores large enough for ribosomes, mitochondria, and sometimes nuclei to flow between cells. The major structural polymer in fungal cell walls is typically chitin, in contrast to plants and oomycetes that have cellulosic cell walls. Some fungi have aseptate hyphae, meaning their hyphae are not partitioned by septa. Hyphae have an average diameter of 4–6 µm. Growth Hyphae grow at their tips. During tip growth, cell walls are extended by the external assembly and polymerization of cell wall components, and the internal production of new cell membrane. The S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunodeficiency
Immunodeficiency, also known as immunocompromisation, is a state in which the immune system's ability to fight infectious diseases and cancer is compromised or entirely absent. Most cases are acquired ("secondary") due to extrinsic factors that affect the patient's immune system. Examples of these extrinsic factors include HIV infection and environmental factors, such as nutrition. Immunocompromisation may also be due to genetic diseases/flaws such as SCID. In clinical settings, immunosuppression by some drugs, such as steroids, can either be an adverse effect or the intended purpose of the treatment. Examples of such use is in organ transplant surgery as an anti- rejection measure and in patients with an overactive immune system, as in autoimmune diseases. Some people are born with intrinsic defects in their immune system, or primary immunodeficiency. A person who has an immunodeficiency of any kind is said to be immunocompromised. An immunocompromised individual may particular ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrophage
Macrophages (abbreviated as M φ, MΦ or MP) ( el, large eaters, from Greek ''μακρός'' (') = large, ''φαγεῖν'' (') = to eat) are a type of white blood cell of the immune system that engulfs and digests pathogens, such as cancer cells, microbes, cellular debris, and foreign substances, which do not have proteins that are specific to healthy body cells on their surface. The process is called phagocytosis, which acts to defend the host against infection and injury. These large phagocytes are found in essentially all tissues, where they patrol for potential pathogens by amoeboid movement. They take various forms (with various names) throughout the body (e.g., histiocytes, Kupffer cells, alveolar macrophages, microglia, and others), but all are part of the mononuclear phagocyte system. Besides phagocytosis, they play a critical role in nonspecific defense (innate immunity) and also help initiate specific defense mechanisms (adaptive immunity) by recruiting other immune ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
