In biology and medicine, the term self-limiting may describe a medical condition, or it may describe an organism or colony.
A self-limiting organism or colony of organisms limits its own growth by its actions. [1] For example, a single organism may have a maximum size determined by genetics, or a colony of organisms may release waste which is ultimately toxic to the colony once it exceeds a certain population. In some cases, the self-limiting nature of a colony may be advantageous to the continued survival of the colony, such as in the case of parasites. If their numbers became too high, they would kill the host, and thus themselves. In other cases, self-limitation restricts the viability of predators, thus ensuring the long-term survival of rare species. [2]
When referring to a medical condition the term may imply that a condition would run its course without the need of external influence, especially any medical treatment. However, the fact that a condition may be self-limiting does not mean that medical treatment would not bring the condition or its symptoms to an end more quickly, or that such medical attention would be unnecessary in severe cases. [3] [4]
A disease is a particular abnormal condition that adversely affects the structure or function of all or part of an organism and is not immediately due to any external injury. Diseases are often known to be medical conditions that are associated with specific signs and symptoms. A disease may be caused by external factors such as pathogens or by internal dysfunctions. For example, internal dysfunctions of the immune system can produce a variety of different diseases, including various forms of immunodeficiency, hypersensitivity, allergies, and autoimmune disorders.
Ploidy is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Sets of chromosomes refer to the number of maternal and paternal chromosome copies, respectively, in each homologous chromosome pair, which chromosomes naturally exist as. Somatic cells, tissues, and individual organisms can be described according to the number of sets of chromosomes present : monoploid, diploid, triploid, tetraploid, pentaploid, hexaploid, heptaploid or septaploid, etc. The generic term polyploid is often used to describe cells with three or more sets of chromosomes.
In genetics, the phenotype is the set of observable characteristics or traits of an organism. The term covers the organism's morphology, its developmental processes, its biochemical and physiological properties, its behavior, and the products of behavior. An organism's phenotype results from two basic factors: the expression of an organism's genetic code and the influence of environmental factors. Both factors may interact, further affecting the phenotype. When two or more clearly different phenotypes exist in the same population of a species, the species is called polymorphic. A well-documented example of polymorphism is Labrador Retriever coloring; while the coat color depends on many genes, it is clearly seen in the environment as yellow, black, and brown. Richard Dawkins in 1978 and then again in his 1982 book The Extended Phenotype suggested that one can regard bird nests and other built structures such as caddisfly larva cases and beaver dams as "extended phenotypes".
Reproduction is the biological process by which new individual organisms – "offspring" – are produced from their "parent" or parents. There are two forms of reproduction: asexual and sexual.
Senescence or biological aging is the gradual deterioration of functional characteristics in living organisms. The word senescence can refer to either cellular senescence or to senescence of the whole organism. Organismal senescence involves an increase in death rates and/or a decrease in fecundity with increasing age, at least in the later part of an organism's life cycle. However, the resulting effects of senescence can be delayed. The 1934 discovery that calorie restriction can extend lifespans by 50% in rats, the existence of species having negligible senescence, and the existence of potentially immortal organisms such as members of the genus Hydra have motivated research into delaying senescence and thus age-related diseases. Rare human mutations can cause accelerated aging diseases.
A multicellular organism is an organism that consists of more than one cell, in contrast to unicellular organism. All species of animals, land plants and most fungi are multicellular, as are many algae, whereas a few organisms are partially uni- and partially multicellular, like slime molds and social amoebae such as the genus Dictyostelium.
In evolutionary biology, inclusive fitness is one of two metrics of evolutionary success as defined by W. D. Hamilton in 1964:
Oral candidiasis, also known as oral thrush among other names, is candidiasis that occurs in the mouth. That is, oral candidiasis is a mycosis of Candida species on the mucous membranes of the mouth.
A heterozygote advantage describes the case in which the heterozygous genotype has a higher relative fitness than either the homozygous dominant or homozygous recessive genotype. Loci exhibiting heterozygote advantage are a small minority of loci. The specific case of heterozygote advantage due to a single locus is known as overdominance. Overdominance is a rare condition in genetics where the phenotype of the heterozygote lies outside of the phenotypical range of both homozygote parents, and heterozygous individuals have a higher fitness than homozygous individuals.
Fecundity is defined in two ways; in human demography, it is the potential for reproduction of a recorded population as opposed to a sole organism, while in population biology, it is considered similar to fertility, the natural capability to produce offspring, measured by the number of gametes (eggs), seed set, or asexual propagules.
Neurasthenia is a term that was first used as early as 1829 for a mechanical weakness of the nerves. It became a major diagnosis in North America during the late nineteenth and early twentieth centuries after neurologist George Miller Beard reintroduced the concept in 1869.
A limiting factor is a variable of a system that causes a noticeable change in output or another measure of a type of system. The limiting factor is in a pyramid shape of organisms going up from the producers to consumers and so on. A factor not limiting over a certain domain of starting conditions may yet be limiting over another domain of starting conditions, including that of the factor.
Ludwig's angina is a type of severe cellulitis involving the floor of the mouth and is often caused by bacterial sources. Early in the infection, the floor of the mouth raises due to swelling, leading to difficulty swallowing saliva. As a result, patients may present with drooling and difficulty speaking. As the condition worsens, the airway may be compromised and hardening of the spaces on both sides of the tongue may develop. Overall, this condition has a rapid onset over a few hours.
Mycobacterium avium-intracellulare infection (MAI) is an atypical mycobacterial infection, i.e. one with nontuberculous mycobacteria or NTM, caused by Mycobacterium avium complex (MAC), which is made of two Mycobacterium species, M. avium and M. intracellulare. This infection causes respiratory illness in birds, pigs, and humans, especially in immunocompromised people. In the later stages of AIDS, it can be very severe. It usually first presents as a persistent cough. It is typically treated with a series of three antibiotics for a period of at least six months.
In biomedical contexts, a biomarker, or biological marker, is a measurable indicator of some biological state or condition. Biomarkers are often measured and evaluated using blood, urine, or soft tissues to examine normal biological processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention. Biomarkers are used in many scientific fields.
Campylobacter upsaliensis is a gram-negative bacteria in the Campylobacter genus. C. upsaliensis is found worldwide, and is a common cause of campylobacteriosis in humans, as well as gastroenteritis in dogs and cats. Human infections are primarily associated with raw or undercooked meat and contaminated water sources, however there is some zoonotic risk associated with the spread from dogs and cats. C. upsaliensis primarily affects the gastrointestinal tract as it damages gastrointestinal epithelial cells. There are many methods for detecting C.upsaliensis including PCR and ELISA, however there is no current gold standard in detection techniques. Infection is typically self limiting, however there is antimicrobial therapy available.
A hermaphrodite is a sexually reproducing organism that produces both male and female gametes. Animal species in which individuals are of different sexes, either male or female but not both, are gonochoric, which is the opposite of hermaphroditic.
An organism is any biological living system that functions as an individual life form. All organisms are composed of cells. The idea of organism is based on the concept of minimal functional unit of life. Three traits have been proposed to play the main role in qualification as an organism:
Targeted drug delivery is one of many ways researchers seek to improve drug delivery systems' overall efficacy, safety, and delivery. Within this medical field is a special reversal form of drug delivery called chemotactic drug targeting. By using chemical agents to help guide a drug carrier to a specific location within the body, this innovative approach seeks to improve precision and control during the drug delivery process, decrease the risk of toxicity, and potentially lower the required medical dosage needed. The general components of the conjugates are designed as follows: (i) carrier – regularly possessing promoter effect also on internalization into the cell; (ii) chemotactically active ligands acting on the target cells; (iii) drug to be delivered in a selective way and (iv) spacer sequence which joins drug molecule to the carrier and due to it enzyme labile moiety makes possible the intracellular compartment specific release of the drug. Careful selection of chemotactic component of the ligand not only the chemoattractant character could be expended, however, chemorepellent ligands are also valuable as they are useful to keep away cell populations degrading the conjugate containing the drug. In a larger sense, chemotactic drug-targeting has the potential to improve cancer, inflammation, and arthritis treatment by taking advantage of the difference in environment between the target site and its surroundings. Therefore, this Wikipedia article aims to provide a brief overview of chemotactic drug targeting, the principles behind the approach, possible limitations and advantages, and its application to cancer and inflammation.
Cat-scratch disease (CSD) or felinosis is an infectious disease that most often results from a scratch or bite of a cat. Symptoms typically include a non-painful bump or blister at the site of injury and painful and swollen lymph nodes. People may feel tired, have a headache, or a fever. Symptoms typically begin within 3–14 days following infection.