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Topic Review
Psychiatric Survivors Movement
The psychiatric survivors movement (more broadly consumer/survivor/ex-patient movement) is a diverse association of individuals who either currently access mental health services (known as consumers or service users), or who are survivors of interventions by psychiatry, or who are ex-patients of mental health services. The psychiatric survivors movement arose out of the civil rights movement of the late 1960s and early 1970s and the personal histories of psychiatric abuse experienced by some ex-patients. The key text in the intellectual development of the survivor movement, at least in the USA, was Judi Chamberlin's 1978 text, On Our Own: Patient Controlled Alternatives to the Mental Health System. Chamberlin was an ex-patient and co-founder of the Mental Patients' Liberation Front. Coalescing around the ex-patient newsletter Dendron, in late 1988 leaders from several of the main national and grassroots psychiatric survivor groups felt that an independent, human rights coalition focused on problems in the mental health system was needed. That year the Support Coalition International (SCI) was formed. SCI's first public action was to stage a counter-conference and protest in New York City , in May, 1990, at the same time as (and directly outside of) the American Psychiatric Association's annual meeting. In 2005 the SCI changed its name to MindFreedom International with David W. Oaks as its director. Common themes are "talking back to the power of psychiatry", rights protection and advocacy, and self-determination. While activists in the movement may share a collective identity to some extent, views range along a continuum from conservative to radical in relation to psychiatric treatment and levels of resistance or patienthood.
  • 3.8K
  • 23 Nov 2022
Topic Review
Hereditary Hemochromatosis
The environment and the human genome are closely entangled and many genetic variations that occur in human populations are the result of adaptive selection to ancestral environmental (mainly dietary) conditions. However, the selected mutations may become maladaptive when environmental conditions change, thus becoming candidates for diseases. Hereditary hemochromatosis (HH) is a potentially lethal disease leading to iron accumulation mostly due to mutations in the HFE gene. Indeed, homozygosity for the C282Y HFE mutation is associated with the primary iron overload phenotype. However, both penetrance of the C282Y variant and the clinical manifestation of the disease are extremely variable, suggesting that other genetic, epigenetic and environmental factors play a role in the development of HH, as well as, and in its progression to end-stage liver diseases. Alcohol consumption and dietary habits may impact on the phenotypic expression of HFE-related hemochromatosis. Indeed, dietary components and bioactive molecules can affect iron status both directly by modulating its absorption during digestion and indirectly by the epigenetic modification of genes involved in its uptake, storage and recycling. Thus, the premise of this review is to discuss how environmental pressures led to the selection of HFE mutations and whether nutritional and lifestyle interventions may exert beneficial effects on HH outcomes and comorbidities.
  • 3.8K
  • 13 Nov 2021
Topic Review
Iris (Anatomy)
In humans and most mammals and birds, the iris (plural: irides or irises) is a thin, circular structure in the eye, responsible for controlling the diameter and size of the pupil and thus the amount of light reaching the retina. Eye color is defined by that of the iris. In optical terms, the pupil is the eye's aperture, while the iris is the diaphragm.
  • 3.8K
  • 11 Oct 2022
Topic Review
Avoidant Personality Disorder
Avoidant personality disorder (AvPD) is a Cluster C personality disorder in which the main coping mechanism of those affected is avoidance of feared stimuli. Those affected display a pattern of severe social anxiety, social inhibition, feelings of inadequacy and inferiority, extreme sensitivity to negative evaluation and rejection, and avoidance of social interaction despite a strong desire for intimacy. People with AvPD often consider themselves to be socially inept or personally unappealing and avoid social interaction for fear of being ridiculed, humiliated, rejected, or disliked. They often avoid becoming involved with others unless they are certain they will be liked. Childhood emotional neglect (in particular, the rejection of a child by one or both parents) and peer group rejection are associated with an increased risk for its development; however, it is possible for AvPD to occur without any notable history of abuse or neglect.
  • 3.8K
  • 20 Oct 2022
Topic Review
Acrylic Bone Cements
Acrylic bone cements (ABC) are widely used in orthopedics for joint fixation, antibiotic release, and bone defect filling, among others. Most of the commercial ABCs available today consist of two components, one solid, based mainly on poly(methyl methacrylate) (PMMA), and one liquid, based on methyl methacrylate (MMA), which are mixed and, through the polymerization reaction of the monomer, transformed into a hardened cement paste. 
  • 3.8K
  • 22 Dec 2020
Topic Review
Empathizing–Systemizing Theory
The empathizing–systemizing (E–S) theory is a theory on the psychological basis of autism and male–female neurological differences originally put forward by English clinical psychologist Simon Baron-Cohen. It classifies individuals based on abilities in empathic thinking (E) and systematic thinking (S). It measures skills using an Empathy Quotient (EQ) and Systemizing Quotient (SQ) and attempts to explain the social and communication symptoms in autism spectrum disorders as deficits and delays in empathy combined with intact or superior systemizing. According to Baron-Cohen, the E–S theory has been tested using the Empathy Quotient (EQ) and Systemizing Quotient (SQ), developed by him and colleagues, and generates five different 'brain types' depending on the presence or absence of discrepancies between their scores on E or S. E–S profiles show that the profile E>S is more common in females than in males, and the profile S>E is more common in males than in females. Baron-Cohen and associates say the E–S theory is a better predictor than gender of who chooses STEM subjects (Science, Technology, Engineering and Mathematics). The E–S theory has been extended into the extreme male brain (EMB) theory of autism and Asperger syndrome, which are associated in the E–S theory with below-average empathy and average or above-average systemizing. Baron-Cohen's studies and theory have faced some criticism.
  • 3.8K
  • 18 Oct 2022
Topic Review
Reduced Affect Display
Reduced affect display, sometimes referred to as emotional blunting, is a condition of reduced emotional reactivity in an individual. It manifests as a failure to express feelings (affect display) either verbally or nonverbally, especially when talking about issues that would normally be expected to engage the emotions. Expressive gestures are rare and there is little animation in facial expression or vocal inflection. Reduced affect can be symptomatic of autism, schizophrenia, depression, posttraumatic stress disorder, depersonalization disorder, schizoid personality disorder or brain damage. It may also be a side effect of certain medications (e.g., antipsychotics and antidepressants). Reduced affect should be distinguished from apathy and anhedonia, which explicitly refer to a lack of emotion, whereas reduced affect is a lack of emotional expression (affect display) regardless of whether emotion (underlying affect) is actually reduced or not.
  • 3.8K
  • 17 Nov 2022
Topic Review
Timeline of Malaria
Malaria is an infectious disease caused by a parasite; it is spread by the bite of an infected mosquito. Every year, 300 to 700 million people get infected. Malaria kills 1 million to 2 million people every year. 90% of the deaths occur in Africa.
  • 3.7K
  • 31 Oct 2022
Topic Review
Pathological Lying
Pathological lying, also known as mythomania and pseudologia fantastica, is a mental disorder in which the person habitually or compulsively lies. The reason for such lies often serves no obvious purpose other than to paint oneself as a hero or victim depending on the circumstance. It was first described in the medical literature in 1895 by Anton Delbrück (de). Although it is a controversial topic, pathological lying has been defined as "falsification entirely disproportionate to any discernible end in view, may be extensive and very complicated, and may manifest over a period of years or even a lifetime". A firm concept of the behaviour does not exist, nor any diagnostic criteria that health professionals accept widely; resulting in controversy regarding what it truly means to be a pathological liar. Theories to explain the root causes include stress, an attempt to shift a locus of control to an internal one, and issues relating to low self-esteem.
  • 3.7K
  • 27 Sep 2022
Topic Review
Biological Half-life
The biological half-life of a biological substance is the time it takes for half to be removed by biological processes. This concept is used when the rate of removal is roughly exponential. It is often denoted by the abbreviation [math]\displaystyle{ t_{\frac{1}{2}} }[/math]. This is used to measure the removal of things such as metabolites, drugs, and signalling molecules from the body. Typically, the biological half-life refers to the body's natural cleansing through the function of the liver and through the excretion of the measured substance through the kidneys and intestines. In a medical context, half-life explicitly describes the time it takes for the blood plasma concentration of a substance to halve (plasma half-life) its steady-state when circulating in the full blood of an organism. This measurement is useful in medicine and pharmacology because it helps determine how much of a drug needs to be taken and how frequently it needs to be taken if a certain average amount is needed constantly. In contrast, the stability of a substance direct in plasma is described with plasma stability that is essential to ensure accurate analysis of drugs in plasma and for Drug discovery. The relationship between the biological and plasma half-lives of a substance can be complex depending on the substance in question, due to factors including accumulation in tissues (protein binding), active metabolites, and receptor interactions.
  • 3.7K
  • 17 Nov 2022
Topic Review
Collagen in Wound Healing
Collagens are the most abundant protein found throughout the body. In the healing wound, these collagens are synthesized by cells such as fibroblasts and modified into complex morphologies . The type, amount and organization of collagen changes in the healing wound and determines the tensile strength of the healed skin. Collagen III is the first to be synthesized in the early stages of wound healing and is replaced by collagen I, the dominant skin collagen. The initial random deposition of collagen during the granulation tissue formation is further enhanced by lysyl oxidase enzyme-induced covalent cross-linking. This process matures the collagen into complex structures that are reoriented for tensile strength restoration. Collagen remodeling continues for months after wound closure and the tensile strength of the repaired tissue increases to about 80–85% of normal tissue if all processes proceed without any perturbations.In the skin, the fibrillar collagens types I, III and V are the most common, followed by fibril-associated collagens type XII, XIV, XVI, and VI. The non-fibrillar collagens type IV, XVIII are found in the basement membrane of the skin
  • 3.7K
  • 23 Jun 2021
Topic Review
Alteplase
Alteplase (t-PA), a biosynthetic form of human tissue-type plasminogen activator (t-PA), is a thrombolytic medication, used to treat acute ischemic stroke, acute ST-elevation myocardial infarction (a type of heart attack), pulmonary embolism associated with low blood pressure, and blocked central venous catheter. It is given by injection into a vein or artery. Alteplase is the same as the normal human plasminogen activator produced in vascular endothelial cells and is synthesized via recombinant DNA technology in Chinese hamster ovary cells (CHO). Alteplase causes the breakdown of a clot by inducing fibrinolysis.
  • 3.7K
  • 31 Oct 2022
Topic Review
Adenosine Deaminase
Adenosine deaminase (ADA, EC 3.5.4.4) - the enzyme engaged in purine metabolism that irreversibly converts adenosine or 2′deoxyadenosine to inosine or 2′deoxyinosine, respectively. In human tissues, it occurs as two isoenzymes: ADA1 and ADA2. ADA1 constitutes the majority of ADA activity and it is present in virtually all tissues, while ADA2 has been found with ADA1 only in monocytes/macrophages. Both ADA isoenzymes are present in cytosolic form, soluble fraction that can be located away from the originating cell, or as ecto-enzymes binding to the cell surface by dedicated proteins. Intracellularly, ADA plays a significant role counteracting high concentrations of 2'deoxyadenosine. When intracellular ADA activity is lowered, e.g. during severe combined immunodeficiency disease (SCID), 2′deoxyadenosine accumulates and is converted to 2′-deoxyadenosine-5′-triphosphate (dATP), which inhibits ribonucleotide reductase (RNR), a crucial enzyme in DNA synthesis that follows disrupted T-cell development. Intracellular concentration of adenosine, the second substrate for ADA, is maintained inside the cell on the low level by adenosine kinase with Km value ~ 1 µM. Under conditions of low energy charge, adenosine-5′-monophosphate (AMP) that originates from adenosine-5′-triphosphate (ATP) degradation, is rapidly transformed to adenosine, which is not immediately deaminated to inosine due to high Km of ADA (25–100 µM). This results in temporary accumulation of adenosine that is vigorously exported out the cell via equilibrative nucleoside transporters (ENTs). Therefore, transmembrane adenosine transport, together with the activities of ecto-ADA and soluble ADA are important regulators of extracellular adenosine concentration. Except enzymatic function, ecto-ADA plays a significant extra-enzymatic role in the interactions between cells that expressed ADA-anchoring proteins on their surfaces. This co-stimulatory and cell-to-cell connecting actions along with its activity regulate many cellular processes related to proliferation and differentiation, which affect pathological conditions associated with cardiovascular diseases such as endothelial activation and dysfunction, inflammation, myocardial ischemia-reperfusion injury, or coagulation disorders. Since these pathologies are associated with ADA overexpression, the inhibition of its activity as well as binding to the surface proteins exhibit an attractive therapeutic potential in cardiovascular diseases.
  • 3.7K
  • 30 Oct 2020
Topic Review
The Mesoporous Silica Nanoparticles
Mesoporous silica nanoparticles (MSNs) are a porous inorganic framework synthesized using the inorganic silica sources sodium silicates or silica tetraethyl orthosilicate as a precursor with quaternary ammonium salts as the surfactant. The size and porosity of MSNs are regulated by various factors such as surfactants, the source of silica, ion strength, aging duration, temperature, and pH. Highly ordered mesoporous silica came into the limelight after the fabrication of the silica-based material Mobile crystalline material 41 (MCM) by Kazuyuki Kuroda’s groups and scientists at Mobil Oil Corporation from aluminium silicate gel. MSNs have a unique porous solid framework with a large surface area facilitating functionalization with various functional groups for targeted drug delivery. MCM-41, MCM-48, and SBA-15 are the most common mesoporous silica materials with two-dimensional hexagonal and three-dimensional cubic structures possessing pore sizes of 2–10 nm.
  • 3.7K
  • 06 May 2023
Topic Review
Child Sexual Abuse
Child sexual abuse, also called child molestation, is a form of child abuse in which an adult or older adolescent uses a child for sexual stimulation. Forms of child sexual abuse include engaging in sexual activities with a child (whether by asking or pressuring, or by other means), indecent exposure (of the genitals, female nipples, etc.), child grooming, or using a child to produce child pornography. Child sexual abuse can occur in a variety of settings, including home, school, or work (in places where child labor is common). Child marriage is one of the main forms of child sexual abuse; UNICEF has stated that child marriage "represents perhaps the most prevalent form of sexual abuse and exploitation of girls". The effects of child sexual abuse can include depression, post-traumatic stress disorder, anxiety, complex post-traumatic stress disorder, propensity to further victimization in adulthood, and physical injury to the child, among other problems. Sexual abuse by a family member is a form of incest and can result in more serious and long-term psychological trauma, especially in the case of parental incest. The global prevalence of child sexual abuse has been estimated at 19.7% for females and 7.9% for males. Most sexual abuse offenders are acquainted with their victims; approximately 30% are relatives of the child, most often brothers, fathers, uncles, or cousins; around 60% are other acquaintances, such as "friends" of the family, babysitters, or neighbors; strangers are the offenders in approximately 10% of child sexual abuse cases. Most child sexual abuse is committed by men; studies on female child molesters show that women commit 14% to 40% of offenses reported against boys and 6% of offenses reported against girls. The word pedophile is commonly applied indiscriminately to anyone who sexually abuses a child, but child sexual offenders are not pedophiles unless they have a strong sexual interest in prepubescent children. Under the law, child sexual abuse is often used as an umbrella term describing criminal and civil offenses in which an adult engages in sexual activity with a minor or exploits a minor for the purpose of sexual gratification. The American Psychological Association states that "children cannot consent to sexual activity with adults", and condemns any such action by an adult: "An adult who engages in sexual activity with a child is performing a criminal and immoral act which never can be considered normal or socially acceptable behavior."
  • 3.6K
  • 14 Nov 2022
Topic Review
Metabolic Equivalent
The Metabolic Equivalent of Task (MET), or simply metabolic equivalent, is a physiological measure expressing the energy cost of physical activities and is defined as the ratio of metabolic rate (and therefore the rate of energy consumption) during a specific physical activity to a reference metabolic rate, set by convention to 3.5 ml O2·kg−1·min−1 or approximately: [math]\displaystyle{ \text{1 MET}\ = 1 \dfrac{\text{kcal}}{\text{kg}*\text{h}}\ = 4.184 \dfrac{\text{kJ}}{\text{kg}*\text{h}} = 1.1622222... \dfrac{\text{W}}{\text{kg}} }[/math] Still another definition of 1 MET is 58.2 W/m2 (18.4 Btu/h·ft2), which is equal to the rate of energy produced per unit surface area of an average person seated at rest. The surface area of an average person is 1.8 m2 (19 ft2). Metabolic rate is usually expressed in terms of unit area of the total body surface (ANSI/ASHRAE Standard 55). Originally, 1 MET was considered as the Resting Metabolic Rate (RMR) obtained during quiet sitting. MET values of activities range from 0.9 (sleeping) to 23 (running at 22.5 km/h or a 4:17 mile pace). Although the RMR of any person may deviate from the reference value, MET can be thought of as an index of the intensity of activities: for example, an activity with a MET value of 2, such as walking at a slow pace (e.g., 3 km/h) would require twice the energy that an average person consumes at rest (e.g., sitting quietly). MET is used as a means of expressing the intensity and energy expenditure of activities in a way comparable among persons of different weight. Actual energy expenditure (e.g., in calories or joules) during an activity depends on the person's body mass; therefore, the energy cost of the same activity will be different for persons of different weight. However, since the RMR is also dependent on body mass in a similar way, it is assumed that the ratio of this energy cost to the RMR of each person will remain more or less stable for the specific activity and thus independent of each person's weight. The 1 MET reference value of 1 kcal·kg−1·h−1, is used by convention and refers to a typical metabolism at rest of an "average" individual. It is not an approximation of Basal Metabolic Rate (BMR), which is the minimum metabolic rate obtained under specified conditions. This is illustrated by sleeping having a MET of 0.9, while an individual's normal sleeping metabolism may be greater than the BMR.
  • 3.6K
  • 14 Oct 2022
Topic Review
Epidemiology of Plague
Globally about 600 cases of plague are reported a year. In 2017 and November 2019 the countries with the most cases include the Democratic Republic of the Congo, Madagascar , and Peru. Local outbreaks of the plague are grouped into three plague pandemics, whereby the respective start and end dates and the assignment of some outbreaks to either pandemic are still subject to discussion. The pandemics were: However, the late medieval Black Death (roughly 1331 to 1353) is sometimes seen not as the start of the second, but as the end of the first pandemic – in that case, the first pandemic ended in around 1353, and the second pandemic's start would be about 1361. Also various end dates of the second pandemic are given in the literature, ranging from about 1840 to 1890.
  • 3.6K
  • 29 Nov 2022
Topic Review
Poliomyelitis
Poliomyelitis, often called polio or infantile paralysis, is an infectious disease caused by the poliovirus. In about 0.5 percent of cases there is muscle weakness resulting in an inability to move. This can occur over a few hours to a few days. The weakness most often involves the legs but may less commonly involve the muscles of the head, neck and diaphragm. Many people fully recover. In those with muscle weakness about 2 to 5 percent of children and 15 to 30 percent of adults die. Another 25 percent of people have minor symptoms such as fever and a sore throat and up to 5 percent have headache, neck stiffness and pains in the arms and legs. These people are usually back to normal within one or two weeks. In up to 70 percent of infections there are no symptoms. Years after recovery post-polio syndrome may occur, with a slow development of muscle weakness similar to that which the person had during the initial infection. Poliovirus is usually spread from person to person through infected fecal matter entering the mouth. It may also be spread by food or water containing human feces and less commonly from infected saliva. Those who are infected may spread the disease for up to six weeks even if no symptoms are present. The disease may be diagnosed by finding the virus in the feces or detecting antibodies against it in the blood. The disease only occurs naturally in humans. The disease is preventable with the polio vaccine; however, multiple doses are required for it to be effective. The US Centers for Disease Control and Prevention recommends polio vaccination boosters for travelers and those who live in countries where the disease is occurring. Once infected there is no specific treatment. In 2016, there were 37 cases of wild polio and 5 cases of vaccine-derived polio. This is down from 350,000 wild cases in 1988. In 2014 the disease was only spreading between people in Afghanistan, Nigeria, and Pakistan . In 2015 Nigeria had stopped the spread of wild poliovirus but it reoccurred in 2016. Poliomyelitis has existed for thousands of years, with depictions of the disease in ancient art. The disease was first recognized as a distinct condition by the English physician Michael Underwood in 1789 and the virus that causes it was first identified in 1908 by the Austrian immunologist Karl Landsteiner. Major outbreaks started to occur in the late 19th century in Europe and the United States. In the 20th century it became one of the most worrying childhood diseases in these areas. The first polio vaccine was developed in the 1950s by Jonas Salk. It was hoped that vaccination efforts and early detection of cases would result in global eradication of the disease by 2018.
  • 3.6K
  • 10 Nov 2022
Topic Review
Applications of Lysozyme
Lysozyme (or muramidase or N-acetylmuramic acid hydrolase E.C. 3.2.1.17) is a protein that exerts its enzymatic activity through the hydrolysis of the β-1,4-glycosidic bonds between N-acetylmuramic acid (NAM) and N-acetylglucosamide (NAG) in the polysaccharide backbone of the peptidoglycans of the Gram-positive bacterial cell wall. Peptidoglycan is composed of polysaccharide chains cross-linked by short peptides. The polysaccharide chains contain alternate units of NAM and NAG.
  • 3.6K
  • 24 Jan 2022
Topic Review
Wearable Biosensors
Recent advances in lab-on-a-chip technology establish solid foundations for wearable biosensors. These newly emerging wearable biosensors are capable of non-invasive, continuous monitoring by miniaturization of electronics and integration with microfluidics. The advent of flexible electronics, biochemical sensors, soft microfluidics, and pain-free microneedles have created new generations of wearable biosensors that explore brand-new avenues to interface with the human epidermis for monitoring physiological status. However, these devices are relatively underexplored for sports monitoring and analytics, which may be largely facilitated by the recent emergence of wearable biosensors characterized by real-time, non-invasive, and non-irritating sensing capacities.
  • 3.5K
  • 18 Jan 2021
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