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Topic Review
Biography
Topic Review
16p12.2 Microdeletion
16p12.2 microdeletion is a chromosomal change in which a small amount of genetic material on chromosome 16 is deleted. The deletion occurs on the short (p) arm of the chromosome at a location designated p12.2. Common characteristics that have been described in people with a 16p12.2 microdeletion include developmental delay, delayed speech, intellectual disability that ranges from mild to profound, weak muscle tone (hypotonia), slow growth resulting in short stature, an usually small head (microcephaly), malformations of the heart, recurrent seizures (epilepsy), and psychiatric and behavioral problems.
1.4K
23 Dec 2020
Topic Review
16S rRNA Next-Generation Sequencing
The 16S rRNA gene is highly conserved in all bacteria (and also archaea). Nonetheless, it contains nine hypervariable regions (V1 - V9), where sequences of these regions can be used to identify and discriminate bacterial genus, sometimes until the species level. This makes the gene a useful tool for phylogenetic studies. With the introduction of next-generation sequencing technologies, 16S rRNA next-generation sequencing (16SNGS) has allowed profiling of bacterial communities found in organisms and the environment, and lead to the discovery of many previously unculturable members of the bacteria kingdom.
4.1K
18 May 2021
Topic Review
17 Alpha-Hydroxylase/17,20-Lyase Deficiency
17 alpha(α)-hydroxylase/17,20-lyase deficiency is a condition that affects the function of certain hormone-producing glands called the gonads (ovaries in females and testes in males) and the adrenal glands. The gonads direct sexual development before birth and during puberty and are important for reproduction. The adrenal glands, which are located on top of the kidneys, regulate the production of certain hormones, including those that control salt levels in the body. People with 17α-hydroxylase/17,20-lyase deficiency have an imbalance of many of the hormones that are made in these glands. 17α-hydroxylase/17,20-lyase deficiency is one of a group of disorders, known as congenital adrenal hyperplasias, that impair hormone production and disrupt sexual development and maturation.
717
23 Dec 2020
Topic Review
17-Beta Hydroxysteroid Dehydrogenase 3 Deficiency
17-beta hydroxysteroid dehydrogenase 3 deficiency is a condition that affects male sexual development. People with this condition are genetically male, with one X and one Y chromosome in each cell, and they have male gonads (testes). Their bodies, however, do not produce enough of a male sex hormone (androgen) called testosterone. Testosterone has a critical role in male sexual development, and a shortage of this hormone disrupts the formation of the external sex organs before birth.
835
23 Dec 2020
Topic Review
1769 Transit of Venus Observed from Tahiti
On June 3, 1769, British navigator Captain James Cook, British naturalist Joseph Banks, British astronomer Charles Green and Swedish naturalist Daniel Solander recorded the transit of Venus on the island of Tahiti during Cook's first voyage around the world. During a transit, Venus appears as a small black disc travelling across the Sun. This unusual astronomical phenomenon takes place in a pattern that repeats itself every 243 years. It includes two transits that are eight years apart, separated by breaks of 121.5 and 105.5 years. These men, along with a crew of scientists, were commissioned by the Royal Society of London for the primary purpose of viewing the transit of Venus. Not only would their findings help expand scientific knowledge, it would help with navigation by accurately calculating the observer's longitude. At this time, longitude was difficult to determine and not always precise. A "secret" mission that followed the transit included the exploration of the South Pacific to find the legendary Terra Australis Incognita or "unknown land of the South."
1.2K
30 Sep 2022
Topic Review
177Lu-PSMA Therapy
177Lu-PSMA (prostate specific membrane antigen) therapy is used for metastatic castration-resistant prostate cancer (mCRPC). Although there are some different approaches regarding the use of 177Lu-PSMA therapy in different countries, this type of therapy is generally safe, with a low toxicity profile. From the oncological point of view, a PSA (prostate specific antigen) decline of ≥50% was seen in 10.6–69% of patients with mCRPC; whereas progression-free survival (PFS) was reported to be 3–13.7 months in different studies. Consequently, 177Lu-PSMA therapy is a promising treatment in patients with mCRPC, with good clinical efficacy, even in heavily pretreated patients with multiple lines of systemic therapy. Currently, there are ongoing clinical trials in the United States, including a phase III multicenter FDA registration trial.
747
23 Jun 2021
Topic Review
17O in Hydrological Cycle
17O is the one of the naturally occurring stable isotopes of oxygen, and also it has the lowest abundance, 0.038%(). The distribution of isotopes in hydrological systems is controlled by isotope fractionation processes. Oxygen isotopes fractionate through mass-dependent isotopic fractionation, which includes kinetic processes, isotopic exchange reactions, and physicochemical phenomena (diffusion, condensation, and evaporation).
1.4K
03 Aug 2021
Topic Review
17q12 Deletion Syndrome
17q12 deletion syndrome is a condition that results from the deletion of a small piece of chromosome 17 in each cell. The deletion occurs on the long (q) arm of the chromosome at a position designated q12.
767
23 Dec 2020
Topic Review
17q12 duplication
17q12 duplication is a chromosomal change in which a small piece of chromosome 17 is copied (duplicated) abnormally in each cell. The duplication occurs on the long (q) arm of the chromosome at a position designated q12.
841
23 Dec 2020
Topic Review
18 kDa Translocator Protein
Neuroactive steroids are potent modulators of microglial functions and are capable of counteracting their excessive reactivity. This action has mainly been ascribed to neuroactive steroids released from other sources, as microglia have been defined unable to produce neurosteroids de novo. Unexpectedly, immortalized murine microglia recently exhibited this de novo biosynthesis; herein, de novo neurosteroidogenesis was characterized in immortalized human microglia. The results demonstrated that C20 and HMC3 microglial cells constitutively express members of the neurosteroidogenesis multiprotein machinery—in particular, the transduceosome members StAR and TSPO, and the enzyme CYP11A1. Moreover, both cell lines produce pregnenolone and transcriptionally express the enzymes involved in neurosteroidogenesis. The high TSPO expression levels observed in microglia prompted us to assess its role in de novo neurosteroidogenesis. TSPO siRNA and TSPO synthetic ligand treatments were used to reduce and prompt TSPO function, respectively. The TSPO expression downregulation compromised the de novo neurosteroidogenesis and led to an increase in StAR expression, probably as a compensatory mechanism.
570
06 May 2021
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