WikiJournal of Medicine is an open-access, free-to-publish, Wikipedia-integrated academic journal for Medical and Biomedical topics.
Wikiversity Journal of Medicine,
Wikipedia medical journal,
Free to publish,
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Authors: Rochelle Tixeira, Ivan Poon, Georgia Atkin-Smith, Aaron Smith, Michael AF Parkes
The disassembly of a dying cell into smaller fragments is a fundamental biological process during apoptosis. Recently, a number of distinct morphologic changes have been identified that could mediate the fragmentation of an apoptotic cell. Presented here is a figure that describes the progression of apoptotic cell disassembly.
Rotavirus is the most common cause of diarrhoeal disease among infants and young children. It is a genus of double-stranded RNA viruses in the family Reoviridae. Nearly every child in the world is infected with rotavirus at least once by the age of five. Immunity develops with each infection, so subsequent infections are less severe; adults are rarely affected. There are eight species of this virus, referred to as A, B, C, D, E, F, G and H. Rotavirus A, the most common species, causes more than 90% of rotavirus infections in humans. The virus is transmitted by the faecal-oral route. It infects and damages the cells that line the small intestine and causes gastroenteritis (which is often called "stomach flu" despite having no relation to influenza). Although rotavirus was discovered in 1973 by Ruth Bishop and her colleagues by electron micrograph images and accounts for approximately one third of hospitalisations for severe diarrhoea in infants and children, its importance has historically been underestimated within the public health community, particularly in developing countries. In addition to its impact on human health, rotavirus also infects animals, and is a pathogen of livestock. Rotavirus is usually an easily managed disease of childhood, but in 2013, rotavirus caused 37 percent of deaths of children from diarrhoea and 215,000 deaths worldwide, and almost two million more become severely ill. Most of these deaths occurred in developing countries. In the United States, before initiation of the rotavirus vaccination programme, rotavirus caused about 2.7 million cases of severe gastroenteritis in children, almost 60,000 hospitalisations, and around 37 deaths each year. Following rotavirus vaccine introduction in the United States, hospitalisation rates have fallen significantly. Public health campaigns to combat rotavirus focus on providing oral rehydration therapy for infected children and vaccination to prevent the disease. The incidence and severity of rotavirus infections has declined significantly in countries that have added rotavirus vaccine to their routine childhood immunisation policies.
Gastrointestinal bleeding (GI bleed) is a common and potentially life-threatening reason for emergency room and intensive care unit admission. This article reports the case of an 83-year-old man with acute GI bleeding from an unusual cause. The clinical information is presented in a step-by-step and question-answer format for learning purposes. This paper is particularly aimed at an internal medicine readership.
Background: Community-acquired pneumonia (CAP) is a major cause of mortality and morbidity among infants and children, particularly in low and middle income countries. Vitamin D, which plays a role in innate as well as adaptive immunity, is a candidate low-cost intervention as an adjunct for treatment of CAP. Methods: We searched multiple electronic databases as well as grey literature to search for randomised controlled trials (RCTs) on vitamin D as an adjunct in infants and children with CAP. We used the Cochrane methodology for assessing risk of bias and, where adequate data was available, conducted a meta-analysis using a fixed or random-effects model as applicable. We assessed overall evidence quality using the GRADE approach. Findings: We screened 272 unique papers and 25 clinical trial registry records and identified three completed and three ongoing trials based on our inclusion criteria. Two completed trials were from India and one from Afghanistan. These three RCTs included a total of 977 participants. Baseline and follow-up vitamin D status was reported in only one RCT. There was no significant effect of vitamin D noted on clinical cure rates (risk ratio (RR) 1.01; 95% confidence interval (CI) 0.91, 1.13; one study, 200 participants, low quality on GRADE), and all-cause mortality (RR 1.01; 95% CI 0.23, 4.41; three trials, 977 participants, low quality on GRADE). Pooled analyses was not possible for the outcomes of time to clinical recovery of pneumonia and total duration of hospital stay, but none of the trials which studied them demonstrated any significant effect of vitamin D on these outcomes individually. Conclusions: There is insufficient evidence available from RCTs to justify the routine use of vitamin D in infants and children with CAP currently and more research is needed to understand several issues related to this. Registration: PROSPERO ID 2014:CRD42014010259
Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) is a family of proteins present on the membrane surface of red blood cells (RBCs or erythrocytes) that are infected by the malarial parasite Plasmodium falciparum. PfEMP1 is synthesized during the parasite's blood stage (erythrocytic schizogony) inside the RBC, during which the clinical symptoms of falciparum malaria are manifested. Acting as both an antigen and adhesion protein, it is thought to play a key role in the high level of virulence associated with P. falciparum. It was discovered in 1984 when it was reported that infected RBCs had unusually large-sized cell membrane proteins, and these proteins had antibody-binding (antigenic) properties. An elusive protein, its chemical structure and molecular properties were revealed only after a decade, in 1995. It is now established that there is not one but a large family of PfEMP1 proteins, genetically regulated (encoded) by a group of about 60 genes called var. Each P. falciparum is able to switch on and off specific var genes to produce a functionally different protein, rendering evasion from the host's immune system. RBCs carrying PfEMP1 on their surface stick to endothelial cells, which facilitates further binding with uninfected RBCs (through the processes of sequestration and rosetting), ultimately helping the parasite to both spread to other RBCs as well as bringing about the fatal symptoms of P. falciparum malaria.
The hippocampus (named after its resemblance to the seahorse, from the Greek ἱππόκαμπος, "seahorse" from ἵππος hippos, "horse" and κάμπος kampos, "sea monster") is a major component of the brains of humans and other vertebrates. Humans and other mammals have two hippocampi, one in each side of the brain. It belongs to the limbic system and plays important roles in the consolidation of information from short-term memory to long-term memory and spatial memory that enables navigation. The hippocampus is located under the cerebral cortex;(allocortical) and in primates it is located in the medial temporal lobe, underneath the cortical surface. It contains two main interlocking parts: the hippocampus proper (also called Ammon's horn) and the dentate gyrus. In Alzheimer's disease (and other forms of short-term memory loss and disorientation are included among the early symptoms. Damage to the hippocampus can also result from oxygen starvation (hypoxia), encephalitis, or medial temporal lobe epilepsy. People with extensive, bilateral hippocampal damage may experience anterograde amnesia (the inability to form and retain new memories). In rodents as model organisms, the hippocampus has been studied extensively as part of a brain system responsible for spatial memory and navigation. Many neurons in the rat and mouse hippocampus respond as place cells: that is, they fire bursts of action potentials when the animal passes through a specific part of its environment. Hippocampal place cells interact extensively with head direction cells, whose activity acts as an inertial compass, and conjecturally with grid cells in the neighboring entorhinal cortex. Since different neuronal cell types are neatly organized into layers in the hippocampus, it has frequently been used as a model system for studying neurophysiology. The form of neural plasticity known as long-term potentiation (LTP) was first discovered to occur in the hippocampus and has often been studied in this structure. LTP is widely believed to be one of the main neural mechanisms by which memories are stored in the brain.
Genes consist of multiple sequence elements that together encode the functional product and regulate its expression. Despite their fundamental importance, there are few freely available diagrams of gene structure. Presented here are two figures that summarise the different structures found in eukaryotic and prokaryotic genes. Common gene structural elements are colour-coded by their function in regulation, transcription, or translation.
Authors: Thomas Shafee, Mikael Häggström, Diptanshu Das, Gwinyai Masukume
WikiJournal of Medicine is an open access, peer reviewed journal free of publication charges for its authors. It publishes both original research and reviews. It was created in 2014 and has grown rapidly since then. This editorial will highlight its unique features and the developments seen in 2016.