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Border Disease
Border disease (BD) is a viral disease of sheep and goats, primarily causing congenital diseases, but can also cause acute and persistent infections. It first appeared in the border regions of England and Wales in 1959, and has since spread world-wide. Lambs that are born with BD are commonly known as 'hairy shakers' due to the primary presentation of the disease. The disease was recognized before the virus, therefore the common name of the disease predates the understanding of the viral pathology. The virus can cause a significant reduction in the percentage of surviving lambs, thus it has a large economic impact on farmers. Virus Border disease is caused by ''Pestivirus D'', also called simply "border disease virus" (BDV), in the family ''Flaviviridae''. It is the same virus causing the disease. It was given a scientific name in 2018 by the International Committee on Taxonomy of Viruses, after it had been identified. This virus is not host exclusive. It is noncytopathogenic - ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viral Disease
A viral disease (or viral infection) occurs when an organism's body is invaded by pathogenic viruses, and infectious virus particles (virions) attach to and enter susceptible cells. Structural Characteristics Basic structural characteristics, such as genome type, virion shape and replication site, generally share the same features among virus species within the same family. * Double-stranded DNA families: three are non-enveloped (''Adenoviridae'', '' Papillomaviridae'' and ''Polyomaviridae'') and two are enveloped (''Herpesviridae'' and ''Poxviridae''). All of the non-enveloped families have icosahedral capsids. * Partly double-stranded DNA viruses: '' Hepadnaviridae''. These viruses are enveloped. * One family of single-stranded DNA viruses infects humans: '' Parvoviridae''. These viruses are non-enveloped. * Positive single-stranded RNA families: three non-enveloped ('' Astroviridae'', ''Caliciviridae'' and ''Picornaviridae'') and four enveloped ('' Coronaviridae'', '' Fl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horizontal Transmission
Horizontal transmission is the transmission of organisms between biotic and/or abiotic members of an ecosystem that are not in a parent-progeny relationship. This concept has been generalized to include transmissions of infectious agents, symbionts, and cultural traits between humans. Because the evolutionary fate of the agent is not tied to reproductive success of the host, horizontal transmission tends to evolve virulence. It is therefore a critical concept for evolutionary medicine. Biological Pathogen transmission In biological, but not cultural, transmissions the carriers (also known as vectors) may include other species. The two main biological modes of transmission are ''anterior station'' and ''posterior station''. In anterior station, transmission occurs via the bite of an infected organism (the vector), like in malaria, dengue fever, and bubonic plague. Posterior station is transmission via contact with infected feces. Examples are rickettsiae driven diseases ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ELISA
The enzyme-linked immunosorbent assay (ELISA) (, ) is a commonly used analytical biochemistry assay, first described by Eva Engvall and Peter Perlmann in 1971. The assay uses a solid-phase type of enzyme immunoassay (EIA) to detect the presence of a ligand (commonly a protein) in a liquid sample using antibodies directed against the protein to be measured. ELISA has been used as a diagnostic tool in medicine, plant pathology, and biotechnology, as well as a quality control check in various industries. In the most simple form of an ELISA, antigens from the sample to be tested are attached to a surface. Then, a matching antibody is applied over the surface so it can bind the antigen. This antibody is linked to an enzyme and then any unbound antibodies are removed. In the final step, a substance containing the enzyme's substrate is added. If there was binding, the subsequent reaction produces a detectable signal, most commonly a color change. Performing an ELISA involves at le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunosuppression
Immunosuppression is a reduction of the activation or efficacy of the immune system. Some portions of the immune system itself have immunosuppressive effects on other parts of the immune system, and immunosuppression may occur as an adverse reaction to treatment of other conditions. In general, deliberately induced immunosuppression is performed to prevent the body from rejecting an organ transplant. Additionally, it is used for treating graft-versus-host disease after a bone marrow transplant, or for the treatment of auto-immune diseases such as systemic lupus erythematosus, rheumatoid arthritis, Sjögren's syndrome, or Crohn's disease. This is typically done using medications, but may involve surgery ( splenectomy), plasmapheresis, or radiation. A person who is undergoing immunosuppression, or whose immune system is weak for some other reasons (such as chemotherapy or HIV), is said to be '' immunocompromised''. Deliberately induced Administration of immunosuppressive me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gestation
Gestation is the period of development during the carrying of an embryo, and later fetus, inside viviparous animals (the embryo develops within the parent). It is typical for mammals, but also occurs for some non-mammals. Mammals during pregnancy can have one or more gestations at the same time, for example in a multiple birth. The time interval of a gestation is called the '' gestation period''. In obstetrics, '' gestational age'' refers to the time since the onset of the last menses, which on average is fertilization age plus two weeks. Mammals In mammals, pregnancy begins when a zygote (fertilized ovum) implants in the female's uterus and ends once the fetus leaves the uterus during labor or an abortion (whether induced or spontaneous). Humans In humans, pregnancy can be defined clinically or biochemically. Clinically, pregnancy starts from first day of the mother's last period. Biochemically, pregnancy starts when a woman's human chorionic gonadotropin (hCG) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viremia
Viremia is a medical condition where viruses enter the bloodstream and hence have access to the rest of the body. It is similar to ''bacteremia'', a condition where bacteria enter the bloodstream. The name comes from combining the word "virus" with the Greek word for "blood" (''haima''). It usually lasts for 4 to 5 days in the primary condition. Primary versus secondary Primary viremia refers to the initial spread of virus in the blood from the first site of infection. Secondary viremia occurs when primary viremia has resulted in infection of additional tissues via bloodstream, in which the virus has replicated and once more entered the circulation. Usually secondary viremia results in higher viral shedding and viral loads within the bloodstream due to the possibility that the virus is able to reach its natural host cell from the bloodstream and replicate more efficiently than the initial site. An excellent example to profile this distinction is the rabies virus. Usually the viru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leukopenia
Leukopenia () is a decrease in the number of leukocytes (WBC). Found in the blood, they are the white blood cells, and are the body's primary defense against an infection. Thus the condition of leukopenia places individuals at increased risk of infection. Signs and symptoms Symptoms may include: * skin or mouth ulcers * sore throat * cough * difficulty in breathing * light-headedness * fever * chills * body aches. Leukopenia vs. neutropenia Neutropenia, a subtype of leukopenia, refers to a decrease in the number of circulating neutrophil granulocytes, the most abundant white blood cells. The terms ''leukopenia'' and ''neutropenia'' may occasionally be used interchangeably, as the neutrophil count is the most important indicator of infection risk. Agranulocytosis is an acute form of neutropenia. Causes Medical conditions Low white cell count may be due to acute viral infections, such as a cold or influenza. It has been associated with chemotherapy, radiation therapy, mye ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seropositive
Serostatus refers to the presence or absence of a serological marker in the blood. The presence of detectable levels of a specific marker within the serum is considered seropositivity, while the absence of such levels is considered seronegativity. HIV/AIDS The term serostatus is commonly used in HIV/AIDS prevention efforts. In the late 20th and early 21st centuries, social advocacy has emphasized the importance of learning one's HIV/AIDS serostatus in an effort to curtail the spread of the disease. Autoimmune disease Researchers have investigated the effects of autoantibody serostatus on autoimmune disease presentation. Study of seronegative patient populations has led to the identification of additional autoantibodies that could potentially help with diagnosis. See also * Seroconversion In immunology, seroconversion is the development of specific antibodies in the blood serum as a result of infection or immunization, including vaccination. During infection or immunization, ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunostaining
In biochemistry, immunostaining is any use of an antibody-based method to detect a specific protein in a sample. The term "immunostaining" was originally used to refer to the immunohistochemical staining of tissue sections, as first described by Albert Coons in 1941. However, immunostaining now encompasses a broad range of techniques used in histology, cell biology, and molecular biology that use antibody-based staining methods. Techniques Immunohistochemistry Immunohistochemistry or IHC staining of tissue sections (or immunocytochemistry, which is the staining of cells), is perhaps the most commonly applied immunostaining technique. While the first cases of IHC staining used fluorescent dyes (see ''immunofluorescence''), other non-fluorescent methods using enzymes such as peroxidase (see '' immunoperoxidase staining'') and alkaline phosphatase are now used. These enzymes are capable of catalysing reactions that give a coloured product that is easily detectable by light m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bovine Viral Diarrhea Virus
Bovines (subfamily Bovinae) comprise a diverse group of 10 genera of medium to large-sized ungulates, including cattle, bison, African buffalo, water buffalos, and the four-horned and spiral-horned antelopes. The evolutionary relationship between the members of the group is still debated, and their classification into loose tribes rather than formal subgroups reflects this uncertainty. General characteristics include cloven hooves and usually at least one of the sexes of a species having true horns. The largest extant bovine is the gaur. In many countries, bovid milk and meat is used as food by humans. Cattle are kept as livestock almost everywhere except in parts of India and Nepal, where they are considered sacred by most Hindus. Bovids are used as draft animals and as riding animals. Small breeds of domestic bovid, such as the Miniature Zebu, are kept as pets. Bovid leather is durable and flexible and is used to produce a wide range of goods including clothing and bags. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertical Transmission
Vertical transmission of symbionts is the transfer of a microbial symbiont from the parent directly to the offspring. Many metazoan species carry symbiotic bacteria which play a mutualistic, commensal, or parasitic role. A symbiont is acquired by a host via horizontal, vertical, or mixed transmission. Implications Complex interdependence occurs between host and symbiont. The genetic pool of the symbiont is generally smaller and more subject to genetic drift. In true vertical transmission, the evolutionary outcomes of the host and symbiont are linked. If there is mixed transmission, new genetic material may be introduced. Generally, symbionts settle into specific niches and can even transfer part of their genome into the host nucleus. Evolutionary consequences Benefits The mechanism promotes tightly coupled evolutionary pressure, which causes the host and symbiont to function as a holobiont. Disadvantages Evolutionary bottlenecks lead to less symbiont diversity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
