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Histoplasma
''Histoplasma'' is a genus of fungi in the order Onygenales. Species are known human pathogens producing yeast-like states under pathogenic conditions. They are the causative agents of histoplasmosis in humans and epizootic lymphangitis in horses. Forms and stages ''Histoplasma'' species have two forms: their environmental form is hyphal with microconidia and tuberculate macroconidia while their pathogenic form is a small intracellular yeast that exhibits narrow-necked budding and no capsule. Infection occurs through inhalation of microconidia or small mycelial fragments. The dimorphic mold-yeast transforms and enters host macrophages Macrophages (; abbreviated MPhi, φ, MΦ or MP) are a type of white blood cell of the innate immune system that engulf and digest pathogens, such as cancer cells, microbes, cellular debris and foreign substances, which do not have proteins that ... and proliferates within them. Infections are most often seen in immunodeficient individuals. ... [...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. ''Histoplasma 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 ''Histoplasma 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 fami ... [...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. ''H. capsulatum'' is found in soil, often associated with decaying bat guano or bird droppings. Humans may inhale infectious spores after disrupting the soil via excavation or construction. ''H. capsulatum'' has a one to two week incubation period within human lungs before symptoms arise. The disease is common among AIDS patients due to their immunosuppression. From 1938 to 2013 in the US, 105 outbreaks were reported in a total of 26 states and 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 ulcers, parotitis, adrenal insufficiency, uveitis, fibrosing medi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Histoplasma Mississippiense
''Histoplasma'' is a genus of fungi in the order Onygenales. Species are known human pathogens producing yeast-like states under pathogenic conditions. They are the causative agents of histoplasmosis in humans and epizootic lymphangitis in horses. Forms and stages ''Histoplasma'' species have two forms: their environmental form is hyphal with microconidia and tuberculate macroconidia while their pathogenic form is a small intracellular yeast that exhibits narrow-necked budding and no capsule. Infection occurs through inhalation of microconidia or small mycelial fragments. The dimorphic mold-yeast transforms and enters host macrophages and proliferates within them. Infections are most often seen in immunodeficient Immunodeficiency, also known as immunocompromise, 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 affec ... individuals. S ... [...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 rep ... [...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 disease, mosquito-borne infectious disease that affects vertebrates and ''Anopheles'' mosquitoes. Human malaria causes Signs and symptoms, symptoms that typically include fever, Fatigue (medical), fatigue, vomitin ... 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] |
Fungi
A fungus (: fungi , , , or ; or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and mold (fungus), molds, as well as the more familiar mushrooms. These organisms are classified as one of the kingdom (biology)#Six kingdoms (1998), traditional eukaryotic kingdoms, along with Animalia, Plantae, and either Protista or 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 motility, 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 o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunodeficiency
Immunodeficiency, also known as immunocompromise, 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 par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macrophage
Macrophages (; abbreviated MPhi, φ, MΦ or MP) are a type of white blood cell of the innate immune system that engulf and digest 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. This self-protection method can be contrasted with that employed by Natural killer cell, Natural Killer cells. This process of engulfment and digestion is called phagocytosis; it acts to defend the host against infection and injury. Macrophages 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 (adapti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycelium
Mycelium (: mycelia) is a root-like structure of a fungus consisting of a mass of branching, thread-like hyphae. Its normal form is that of branched, slender, entangled, anastomosing, hyaline threads. Fungal colonies composed of mycelium are found in and on soil and many other substrates. A typical single spore germinates into a monokaryotic mycelium, which cannot reproduce sexually; when two compatible monokaryotic mycelia join and form a dikaryotic mycelium, that mycelium may form fruiting bodies such as mushrooms. A mycelium may be minute, forming a colony that is too small to see, or may grow to span thousands of acres as in '' Armillaria''. Through the mycelium, a fungus absorbs nutrients from its environment. It does this in a two-stage process. First, the hyphae secrete enzymes onto or into the food source, which break down biological polymers into smaller units such as monomers. These monomers are then absorbed into the mycelium by facilitated diffusion and ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conidia
A conidium ( ; : conidia), sometimes termed an asexual chlamydospore or chlamydoconidium (: chlamydoconidia), is an asexual, non- motile spore of a fungus. The word ''conidium'' comes from the Ancient Greek word for dust, ('). They are also called mitospores due to the way they are generated through the cellular process of mitosis. They are produced exogenously. The two new haploid cells are genetically identical to the haploid parent, and can develop into new organisms if conditions are favorable, and serve in biological dispersal. Asexual reproduction in ascomycetes (the phylum Ascomycota) is by the formation of conidia, which are borne on specialized stalks called conidiophores. The morphology of these specialized conidiophores is often distinctive between species and, before the development of molecular techniques at the end of the 20th century, was widely used for identification of (''e.g.'' '' Metarhizium'') species. The terms microconidia and macroconidia are some ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
