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Topic Review
Procaviidae
Hyraxes (from grc ὕραξ (Script error: No such module "Ancient Greek".) 'shrewmouse'), also called dassies, are small, thickset, herbivorous mammals in the order Hyracoidea. Hyraxes are well-furred, rotund animals with short tails. Typically, they measure between 30 and 70 cm (12 and 28 in) long and weigh between 2 and 5 kg (4 and 11 lb). They are superficially similar to pikas and marmots, but are more closely related to elephants and sea cows. Hyraxes have a life span from 9 to 14 years. Five extant species are recognised: the rock hyrax (Procavia capensis) and the yellow-spotted rock hyrax (Heterohyrax brucei), which both live on rock outcrops, including cliffs in Ethiopia and isolated granite outcrops called koppies in southern Africa; the western tree hyrax (Dendrohyrax dorsalis), southern tree hyrax (D. arboreus), and eastern tree hyrax (D. validus). Their distribution is limited to Africa, except for P. capensis, which is also found in the Middle East.
  • 1.3K
  • 20 Oct 2022
Topic Review
Peripartum Cardiomyopathy
Peripartum cardiomyopathy (PPCM) is a condition in which heart failure and left ventricular systolic dysfunction occur in the last month of pregnancy or within months following delivery.
  • 1.3K
  • 26 Jan 2021
Topic Review
Curcuma longa L. Essential Oil
Curcuma longa L. rhizome essential oil is a valuable product in pharmaceutical industry due to its wide beneficial health effects.
  • 1.3K
  • 09 Feb 2021
Topic Review
History of Biotechnology
Biotechnology is the application of scientific and engineering principles to the processing of materials by biological agents to provide goods and services. From its inception, biotechnology has maintained a close relationship with society. Although now most often associated with the development of drugs, historically biotechnology has been principally associated with food, addressing such issues as malnutrition and famine. The history of biotechnology begins with zymotechnology, which commenced with a focus on brewing techniques for beer. By World War I, however, zymotechnology would expand to tackle larger industrial issues, and the potential of industrial fermentation gave rise to biotechnology. However, both the single-cell protein and gasohol projects failed to progress due to varying issues including public resistance, a changing economic scene, and shifts in political power. Yet the formation of a new field, genetic engineering, would soon bring biotechnology to the forefront of science in society, and the intimate relationship between the scientific community, the public, and the government would ensue. These debates gained exposure in 1975 at the Asilomar Conference, where Joshua Lederberg was the most outspoken supporter for this emerging field in biotechnology. By as early as 1978, with the development of synthetic human insulin, Lederberg's claims would prove valid, and the biotechnology industry grew rapidly. Each new scientific advance became a media event designed to capture public support, and by the 1980s, biotechnology grew into a promising real industry. In 1988, only five proteins from genetically engineered cells had been approved as drugs by the United States Food and Drug Administration (FDA), but this number would skyrocket to over 125 by the end of the 1990s. The field of genetic engineering remains a heated topic of discussion in today's society with the advent of gene therapy, stem cell research, cloning, and genetically modified food. While it seems only natural nowadays to link pharmaceutical drugs as solutions to health and societal problems, this relationship of biotechnology serving social needs began centuries ago.
  • 1.3K
  • 21 Apr 2023
Topic Review
Thymic Epithelial Cells
The thymus is a primary lymphoid organ derived from the endoderm of the 3rd pharyngeal pouch implicated in the maturation of thymocytes and, therefore, key for establishing the immune surveillance. This organ does not contain self-renewing lymphoid precursor cells and therefore, is colonized by lymphoid precursors coming either from the fetal liver through mesenchyme or from the adult bone marrow via the blood vessels [1]. Within the thymus, the developing thymocytes move throughout a 3D thymic epithelial (TE) network, interacting with the thymic epithelial cells (TECs) of two histologically different compartments: the cortex and the medulla [2].
  • 1.3K
  • 26 Oct 2020
Topic Review
Food Security and Transition towards Sustainability
For decades, food security and sustainability have been considered separate concerns, with the concept of food security having a more significant connotation with sustainability dimensions such as environmental, economic, and social–cultural aspects that interpret human well-being. Food security is highly connected to food sustainability and environmental protection. Additionally, food security exists when all people at all times have physical, economic, and social access to sufficient, safe, and nutritious food. 
  • 1.3K
  • 26 Nov 2021
Topic Review
Red Queen Hypothesis
The Red Queen hypothesis is a hypothesis in evolutionary biology proposed in 1973, that species must constantly adapt, evolve, and proliferate in order to survive while pitted against ever-evolving opposing species. The hypothesis was intended to explain the constant (age-independent) extinction probability as observed in the paleontological record caused by co-evolution between competing species; however, it has also been suggested that the Red Queen hypothesis explains the advantage of sexual reproduction (as opposed to asexual reproduction) at the level of individuals, and the positive correlation between speciation and extinction rates in most higher taxa.
  • 1.3K
  • 22 Nov 2022
Topic Review
Cells Fusion
The biological phenomenon of cell fusion remains a mystery. Even though it is mandatory for several physiological and pathopyhsiological processes considerably less is still known how the merging of two (and more) cells is regulated. Cells are not fusogenic per se. They first have to be converted into a pro-fusogenic state and have to re-enter to a non-fusogenic state after hybridisation. Likewise, different cell fusion mechanisms have been developed during evolution depending on different proteins and different membrane merging strategies. This entry gives a brief overview about those molecules and conditions that direct cell fusion.
  • 1.3K
  • 27 Oct 2020
Topic Review
Osteoclasts and Osteoblasts
The bone is a complex organ that is dependent on a tight regulation between bone formation by osteoblasts (OBs) and bone resorption by osteoclasts (OCs). The OC is a multinucleated giant cell, arising from the fusion of many mononuclear OC precursors with a myeloid/monocyte origin. Differently from OCs, OBs arise from pluripotent mesenchymal stem cells (MSCs). The main function of OBs is the synthesis of new bone matrix. Bone metabolism is regulated by various hormones or cytokines and dysregulation in this complex system can lead to numerous diseases characterized either by enhanced bone resorption (osteoporotic phenotype) or enhanced bone formation (osteopetrotic phenotype).
  • 1.3K
  • 09 May 2021
Topic Review
Receptor Tyrosine Kinases
The receptor tyrosine kinases (RTKs) are a large family of cell-surface receptors, which are essential components of signal transduction pathways. There are more than fifty human RTKs that can be grouped into multiple RTK subfamilies. RTKs mediate cellular signaling transduction, and they play important roles in the regulation of numerous cellular processes. The dysregulation of RTK signaling is related to various human diseases, including cancers. The proteolytic cleavage phenomenon has frequently been found among multiple receptor tyrosine kinases. More and more information about proteolytic cleavage in RTKs has been discovered, providing rich insight.
  • 1.3K
  • 16 May 2021
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