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Topic Review
Teeth Blackening
Teeth blackening or teeth lacquering is a custom of dyeing one's teeth black. It was most predominantly practiced in Southeast Asian and Oceanic cultures, particularly among Austronesian, Austroasiatic, and Kra-Dai-speaking peoples. It was also practiced in Japan prior to the Meiji era, as well as in India. It was also performed among some groups in the Americas, most notably among the Shuar people of northern Peru and Ecuador. Teeth blackening is usually done during puberty. It was primarily done to preserve the teeth into old age, as it prevents tooth decay similar to the mechanism of modern dental sealants. It was seen as a sign of maturity, beauty, and civilization. A common belief is that blackened teeth differentiated humans from animals. Teeth blackening is often done in conjunction with traditions of tooth sharpening and evulsion, as well as other body modification customs like tattoos. Teeth blackening and filing were regarded with fascination and disapproval by early European explorers and colonists. The practice survives in some isolated ethnic groups in Southeast Asia and Oceania but has mostly disappeared after the introduction of Western beauty standards during the colonial era, and continues among many minority groups in China, Pacific Islands and Southeast Asia. It is mainly prevalent in older women, though the practice is still carried on by some younger women. Sometimes artificial teeth are used to achieve blackened teeth. Teeth blackening is commonly confused with the red-stained teeth from betel chewing. However, betel chewing damages the teeth and gums, while teeth blackening does not.
  • 8.7K
  • 21 Nov 2022
Topic Review
Plant-Dominant Low-Protein Diet
Plant-dominant low-protein diet (LPD), also abbreviated as "PLADO" is a patient-centered LPD of 0.6–0.8 g/kg/day composed of >50% plant-based sources, administered by dietitians trained in providing nutrition care to patients with non-dialysis-dependent chronic kidney disease (CKD). PLADO's composition and meal plans can be designed and adjusted based on individualized needs and according to the principles of precision nutrition. The goal of PLADO is to slow kidney disease progression, to avoid or delay dialysis therapy initiation, and to ensure cardiovascular health and longevity.  The ideal type of PLADO is a heart-healthy, safe, flexible, and feasible diet that could be the centerpiece of the conservative and preservative management of CKD.
  • 8.7K
  • 05 Nov 2020
Topic Review
Ego-Dystonic Sexual Orientation
Ego-dystonic sexual orientation is an ego-dystonic mental disorder characterized by having a sexual orientation or an attraction that is at odds with one's idealized self-image, causing anxiety and a desire to change one's orientation or become more comfortable with one's sexual orientation. It describes not innate sexual orientation itself, but a conflict between the sexual orientation one wishes to have and the sexual orientation one actually possesses.
  • 8.5K
  • 14 Oct 2022
Topic Review
List of Phobias
The English suffixes -phobia, -phobic, -phobe (from Greek φόβος phobos, "fear") occur in technical usage in psychiatry to construct words that describe irrational, abnormal, unwarranted, persistent, or disabling fear as a mental disorder (e.g. agoraphobia), in chemistry to describe chemical aversions (e.g. hydrophobic), in biology to describe organisms that dislike certain conditions (e.g. acidophobia), and in medicine to describe hypersensitivity to a stimulus, usually sensory (e.g. photophobia). In common usage, they also form words that describe dislike or hatred of a particular thing or subject (e.g. homophobia). The suffix is antonymic to -phil-. For more information on the psychiatric side, including how psychiatry groups phobias such as agoraphobia, social phobia, or simple phobia, see phobia. The following lists include words ending in -phobia, and include fears that have acquired names. In some cases, the naming of phobias has become a word game, of notable example being a 1998 humorous article published by BBC News. In some cases, a word ending in -phobia may have an antonym with the suffix -phil-, e.g. Germanophobe/Germanophile. Many -phobia lists circulate on the Internet, with words collected from indiscriminate sources, often copying each other. Also, a number of psychiatric websites exist that at the first glance cover a huge number of phobias, but in fact use a standard text to fit any phobia and reuse it for all unusual phobias by merely changing the name. Sometimes it leads to bizarre results, such as suggestions to cure "prostitute phobia". Such practice is known as content spamming and is used to attract search engines. An article published in 1897 in American Journal of Psychology noted "the absurd tendency to give Greek names to objects feared (which, as Arndt says, would give us such terms as klopsophobia – fear of thieves, triakaidekaphobia – fear of the number 13....)".
  • 8.5K
  • 07 Nov 2022
Topic Review
Consanguinity
Consanguinity ("blood relation", from Latin consanguinitas) is the property of being from the same kinship as another person. In that aspect, consanguinity is the quality of being descended from the same ancestor as another person. The laws of many jurisdictions set out the degree of consanguinity in relation to prohibited sexual relations and marriage parties. Such rules are also used to determine heirs of an estate according to statutes that govern intestate succession, which vary from jurisdiction to jurisdiction. In some places and times, cousin marriage is approved and expected; in others, it is taboo as incest. The degree of relative consanguinity can be illustrated with a consanguinity table in which each level of lineal consanguinity (generation or meiosis) appears as a row, and individuals with a collaterally consanguineous relationship share the same row. The Knot System is a numerical notation that defines consanguinity.
  • 8.2K
  • 28 Sep 2022
Topic Review
Natural Reservoir
In infectious disease ecology and epidemiology, a natural reservoir, also known as a disease reservoir or a reservoir of infection, is the population of organisms or the specific environment in which an infectious pathogen naturally lives and reproduces, or upon which the pathogen primarily depends for its survival. A reservoir is usually a living host of a certain species, such as an animal or a plant, inside of which a pathogen survives, often (though not always) without causing disease for the reservoir itself. By some definitions a reservoir may also be an environment external to an organism, such as a volume of contaminated air or water. Because of the enormous variety of infectious microorganisms capable of causing disease, precise definitions for what constitutes a natural reservoir are numerous, various, and often conflicting. The reservoir concept applies only for pathogens capable of infecting more than one host population and only with respect to a defined target population – the population of organisms in which the pathogen causes disease. The reservoir is any population of organisms (or any environment) which harbors the pathogen and transmits it to the target population. Reservoirs may comprise one or more different species, may be the same or a different species as the target, and, in the broadest sense, may include vector species, which are otherwise distinct from natural reservoirs and should not be confused with them. Significantly, species considered reservoirs for a given pathogen may not experience symptoms of disease when infected by the pathogen. Identifying the natural reservoirs of infectious pathogens has proven useful in treating and preventing large outbreaks of disease in humans and domestic animals, especially those diseases for which no vaccine exists. In principle, zoonotic diseases can be controlled by isolating or destroying the pathogen's reservoirs of infection. The mass culling of animals confirmed or suspected as reservoirs for human pathogens, such as birds that harbor avian influenza, has been effective at containing possible epidemics in many parts of the world; for other pathogens, such as the ebolaviruses, the identity of the presumed natural reservoir remains obscure.
  • 7.7K
  • 26 Oct 2022
Topic Review
Pathogenic Bacteria
Pathogenic bacteria are bacteria that can cause disease. This article focuses on the bacteria that are pathogenic to humans. Most species of bacteria are harmless and are often beneficial but others can cause infectious diseases. The number of these pathogenic species in humans is estimated to be fewer than a hundred. By contrast, several thousand species are part of the gut flora present in the digestive tract. The body is continually exposed to many species of bacteria, including beneficial commensals, which grow on the skin and mucous membranes, and saprophytes, which grow mainly in the soil and in decaying matter. The blood and tissue fluids contain nutrients sufficient to sustain the growth of many bacteria. The body has defence mechanisms that enable it to resist microbial invasion of its tissues and give it a natural immunity or innate resistance against many microorganisms. Pathogenic bacteria are specially adapted and endowed with mechanisms for overcoming the normal body defences, and can invade parts of the body, such as the blood, where bacteria are not normally found. Some pathogens invade only the surface epithelium, skin or mucous membrane, but many travel more deeply, spreading through the tissues and disseminating by the lymphatic and blood streams. In some rare cases a pathogenic microbe can infect an entirely healthy person, but infection usually occurs only if the body's defence mechanisms are damaged by some local trauma or an underlying debilitating disease, such as wounding, intoxication, chilling, fatigue, and malnutrition. In many cases, it is important to differentiate infection and colonization, which is when the bacteria are causing little or no harm. Caused by Mycobacterium tuberculosis bacteria, one of the diseases with the highest disease burden is tuberculosis, which killed 1.4 million people in 2019, mostly in sub-Saharan Africa. Pathogenic bacteria contribute to other globally important diseases, such as pneumonia, which can be caused by bacteria such as Streptococcus, Pneumococcus and Pseudomonas, and foodborne illnesses, which can be caused by bacteria such as Shigella, Campylobacter, and Salmonella. Pathogenic bacteria also cause infections such as tetanus, typhoid fever, diphtheria, syphilis, and leprosy. Pathogenic bacteria are also the cause of high infant mortality rates in developing countries. Most pathogenic bacteria can be grown in cultures and identified by Gram stain and other methods. Bacteria grown in this way are often tested to find which antibiotics will be an effective treatment for the infection. For hitherto unknown pathogens, Koch's postulates are the standard to establish a causative relationship between a microbe and a disease.
  • 7.5K
  • 07 Nov 2022
Topic Review
Histopathology of Colorectal Carcinoma
The histopathology of colorectal carcinoma involves analysis of tissue taken from a biopsy or surgery. A pathology report contains a description of the microscopical characteristics of the tumor tissue, including both tumor cells and how the tumor invades into healthy tissues and finally if the tumor appears to be completely removed. The most common form of colon cancer is adenocarcinoma, constituting between 95% to 98% of all cases of colorectal cancer. Other, rarer types include lymphoma, adenosquamous and squamous cell carcinoma. Some subtypes have been found to be more aggressive.
  • 7.4K
  • 09 Nov 2022
Topic Review
Ideas of Reference and Delusions of Reference
Ideas of reference and delusions of reference describe the phenomenon of an individual experiencing innocuous events or mere coincidences and believing they have strong personal significance. It is "the notion that everything one perceives in the world relates to one's own destiny", usually in a negative and hostile manner. In psychiatry, delusions of reference form part of the diagnostic criteria for psychotic illnesses such as schizophrenia, delusional disorder, bipolar disorder (during the elevated stages of mania), as well as schizotypal personality disorder. To a lesser extent, it can be a hallmark of paranoid personality disorder, as well as body dysmorphic disorder. Such symptoms can also be caused by intoxication, such as stimulants like methamphetamine.
  • 7.3K
  • 20 Oct 2022
Topic Review
Sexual Fetishism
Sexual fetishism or erotic fetishism is a sexual fixation on a nonliving object or nongenital body part. The object of interest is called the fetish; the person who has a fetish for that object is a fetishist. A sexual fetish may be regarded as a non-pathological aid to sexual excitement, or as a mental disorder if it causes significant psychosocial distress for the person or has detrimental effects on important areas of their life. Sexual arousal from a particular body part can be further classified as partialism. While medical definitions restrict the term sexual fetishism to objects or body parts, fetish can, in common discourse, also refer to sexual interest in specific activities.
  • 7.2K
  • 14 Oct 2022
Topic Review
Sanism
Mentalism or sanism describes discrimination and oppression against a mental trait or condition a person has, or is judged to have. This discrimination may or may not be characterized in terms of mental disorder or cognitive impairment. The discrimination is based on numerous factors such as stereotypes about neurodivergence, for example autism, learning disorders, ADHD, bipolar, schizophrenia, and personality disorders, specific behavioral phenomena such as stuttering and tics, or intellectual disability. Like other forms of discrimination such as sexism and racism, mentalism involves multiple intersecting forms of oppression, complex social inequalities and imbalances of power. It can result in covert discrimination by multiple, small insults and indignities. It is characterized by judgments of another person's perceived mental health status. These judgments are followed by actions such as blatant, overt discrimination which may include refusal of service, or the denial of human rights. Mentalism impacts how individuals are treated by the general public, by mental health professionals, and by institutions, including the legal system. The negative attitudes involved may also be internalized. The terms mentalism, from "mental", and sanism, from "sane", have become established in some contexts, though concepts such as social stigma, and in some cases ableism, may be used in similar but not identical ways. While mentalism and sanism are used interchangeably, sanism is becoming predominant in certain circles, such as academics, those who identify as mad and mad advocates and in a socio-political context where sanism is gaining ground as a movement. The movement of sanism is an act of resistance among those who identify as mad, consumer survivors, and mental health advocates. In academia evidence of this movement can be found in the number of recent publications about sanism and social work practice. Mentalism tends to be referred as mental disability, distinguishing itself from ableism, which refers to physical disability.
  • 7.0K
  • 02 Nov 2022
Topic Review
Aquaporin Inhibitors
Aquaporins (AQPs) are water channel proteins that are essential to life, being expressed in all kingdoms. In humans, there are 13 AQPs, at least one of which is found in every organ system. The structural biology of the AQP family is well-established and many functions for AQPs have been reported in health and disease. AQP expression is linked to numerous pathologies including tumor metastasis, fluid dysregulation, and traumatic injury. The targeted modulation of AQPs therefore presents an opportunity to develop novel treatments for diverse conditions. Various techniques such as video microscopy, light scattering and fluorescence quenching have been used to test putative AQP inhibitors in both AQP-expressing mammalian cells and heterologous expression systems. The inherent variability within these methods has caused discrepancy and many molecules that are inhibitory in one experimental system (such as tetraethylammonium, acetazolamide, and anti-epileptic drugs) have no activity in others. Some heavy metal ions (that would not be suitable for therapeutic use) and the compound, TGN-020, have been shown to inhibit some AQPs. Clinical trials for neuromyelitis optica treatments using anti-AQP4 IgG are in progress. However, these antibodies have no effect on water transport. More research to standardize high-throughput assays is required to identify AQP modulators for which there is an urgent and unmet clinical need.
  • 6.9K
  • 06 Sep 2021
Topic Review
Social Construction of Disability
The social construction of disability comes from a paradigm of ideas that suggest that society's beliefs about a particular community, group or population are grounded in the power structures inherent in a society at any given time. These are often steeped in historical representations of the issue and social expectations surrounding concepts such as disability, thereby enabling a social construct around what society deems disabled and healthy. Ideas surrounding disability stem from societal attitudes, often connected to who is deserving or undeserving, and deemed productive to society at any given time. For example, in the medieval period, a person's moral behavior established disability. Disability was a divine punishment or side effect of a moral failing; being physically or biologically different was not enough to be considered disabled. Only during the European Enlightenment did society change its definition of disability to be more related to biology. However, what most Western Europeans considered to be healthy determined the new biological definition of health.
  • 6.7K
  • 11 Nov 2022
Topic Review
Transgender Hormone Therapy (Male-to-female)
Transgender hormone therapy of the male-to-female (MTF) type, also known as transfeminine hormone therapy, is hormone therapy and sex reassignment therapy to change the secondary sexual characteristics of transgender people from masculine or androgynous to feminine. It is one of two types of transgender hormone therapy (the other being female-to-male) and is predominantly used to treat transgender women and other transfeminine individuals. Some intersex people also take this form of therapy, according to their personal needs and preferences. The purpose of the therapy is to cause the development of the secondary sex characteristics of the desired sex, such as breasts and a feminine pattern of hair, fat, and muscle distribution. It cannot undo many of the changes produced by naturally occurring puberty, which may necessitate surgery and other treatments to reverse (see below). The medications used for the MTF therapy include estrogens, antiandrogens, progestogens, and gonadotropin-releasing hormone modulators (GnRH modulators). While the therapy cannot undo the effects of a person's first puberty, developing secondary sex characteristics associated with a different gender has been shown to relieve some or all of the distress and discomfort associated with gender dysphoria, and can help the person to "pass" or be seen as the gender they identify with. Introducing exogenous hormones into the body impacts it at every level and many patients report changes in energy levels, mood, appetite, etc. The goal of the therapy is to provide patients with a more satisfying body that is more congruent with their gender identity.
  • 6.7K
  • 06 Oct 2022
Topic Review
Lipid-Based Nanoparticles
COVID-19 vaccines have been developed with unprecedented speed which would not have been possible without decades of fundamental research on delivery nanotechnology. Lipid-based nanoparticles have played a pivotal role in the successes of COVID-19 vaccines and many other nanomedicines, such as Doxil® and Onpattro®, and have therefore been considered as the frontrunner in nanoscale drug delivery systems. In this review, we aim to highlight the progress in the development of these lipid nanoparticles for various applications, ranging from cancer nanomedicines to COVID-19 vaccines. The lipid-based nanoparticles discussed in this review are liposomes, niosomes, transfersomes, solid lipid nanoparticles, and nanostructured lipid carriers. We particularly focus on the innovations that have obtained regulatory approval or that are in clinical trials. We also discuss the physicochemical properties required for specific applications, highlight the differences in requirements for the delivery of different cargos, and introduce current challenges that need further development. This review serves as a useful guideline for designing new lipid nanoparticles for both preventative and therapeutic vaccines including immunotherapies.
  • 6.6K
  • 19 May 2021
Topic Review
The Pathogenesis of Epilepsy
Epilepsy is a chronic neurological disorder characterized by recurring spontaneous seizures. Drug resistance appears in 30% of patients and it can lead to premature death, brain damage or a reduced quality of life. The purpose of the study was to analyze the drug resistance mechanisms, especially neuroinflammation, in the epileptogenesis. The information bases of biomedical literature Scopus, PubMed, Google Scholar and SciVerse were used. To obtain full-text documents, electronic resources of PubMed Central and Research Gate were used. The article examines the recent research of the mechanisms of drug resistance in epilepsy and discusses the hypotheses of drug resistance development (genetic, epigenetic, target hypothesis, etc.). Drug-resistant epilepsy is associated with neuroinflammatory, autoimmune and neurodegenerative processes. Neuroinflammation causes immune, pathophysiological, biochemical and psychological consequences. Focal or systemic unregulated inflammatory processes lead to the formation of aberrant neural connections and hyperexcitable neural networks. Inflammatory mediators affect the endothelium of cerebral vessels, destroy contacts between endothelial cells and induce abnormal angiogenesis (the formation of “leaky” vessels), thereby affecting the blood–brain barrier permeability. Thus, the analysis of pro-inflammatory and other components of epileptogenesis can contribute to the further development of the therapeutic treatment of drug-resistant epilepsy.
  • 6.4K
  • 26 May 2021
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.
  • 6.4K
  • 18 May 2021
Topic Review
Personality Test
A personality test is a method of assessing human personality constructs. Most personality assessment instruments (despite being loosely referred to as "personality tests") are in fact introspective (i.e., subjective) self-report questionnaire (Q-data, in terms of LOTS data) measures or reports from life records (L-data) such as rating scales. Attempts to construct actual performance tests of personality have been very limited even though Raymond Cattell with his colleague Frank Warburton compiled a list of over 2000 separate objective tests that could be used in constructing objective personality tests. One exception however, was the Objective-Analytic Test Battery, a performance test designed to quantitatively measure 10 factor-analytically discerned personality trait dimensions. A major problem with both L-data and Q-data methods is that because of item transparency, rating scales and self-report questionnaires are highly susceptible to motivational and response distortion ranging all the way from lack of adequate self-insight (or biased perceptions of others) to downright dissimulation (faking good/faking bad) depending on the reason/motivation for the assessment being undertaken. The first personality assessment measures were developed in the 1920s and were intended to ease the process of personnel selection, particularly in the armed forces. Since these early efforts, a wide variety of personality scales and questionnaires have been developed, including the Minnesota Multiphasic Personality Inventory (MMPI), the Sixteen Personality Factor Questionnaire (16PF), the Comrey Personality Scales (CPS), among many others. Although popular especially among personnel consultants, the Myers–Briggs Type Indicator (MBTI) has numerous psychometric deficiencies. More recently, a number of instruments based on the Five Factor Model of personality have been constructed such as the Revised NEO Personality Inventory. However, the Big Five and related Five Factor Model have been challenged for accounting for less than two-thirds of the known trait variance in the normal personality sphere alone. Estimates of how much the personality assessment industry in the US is worth range anywhere from $2 and $4 billion a year (as of 2013). Personality assessment is used in wide a range of contexts, including individual and relationship counseling, clinical psychology, forensic psychology, school psychology, career counseling, employment testing, occupational health and safety and customer relationship management.
  • 6.3K
  • 13 Oct 2022
Topic Review
Euro Health Consumer Index
Euro Health Consumer Index (EHCI) is a comparison of European health care systems based on waiting times, results, and generosity. The information is presented as a graphic index. EHCI was produced 2005–2009 and 2012–2016 by Health Consumer Powerhouse. The 2014 ranking included 37 countries measured by 48 indicators. It claims to measure the "consumer friendliness" of healthcare systems. It does not claim to measure which European state has the best healthcare system, but it does produce specialist Indexes on Diabetes, Cardiac Care, HIV, Headache and Hepatitis. In 2006 France was the champion with 768 points out of 1000. In the 2015 results the same performance would have given the 13th position among 35 countries because of the widespread improvements in standards. While no bias in favour of any health system was alleged, the index was criticised in the British Medical Journal by Martin McKee and others from the European Observatory on Health Systems and Policies in February 2016. Points they made included: A survey by the Centre for Population Change in 2019 produced results consistent with the index.
  • 6.3K
  • 09 Nov 2022
Topic Review
Iridology
Iridology (also known as iridodiagnosis or iridiagnosis) is an alternative medicine technique whose proponents claim that patterns, colors, and other characteristics of the iris can be examined to determine information about a patient's systemic health. Practitioners match their observations to iris charts, which divide the iris into zones that correspond to specific parts of the human body. Iridologists see the eyes as "windows" into the body's state of health. Iridologists claim they can use the charts to distinguish between healthy systems and organs in the body and those that are overactive, inflamed, or distressed. Iridologists claim this information demonstrates a patient's susceptibility towards certain illnesses, reflects past medical problems, or predicts later health problems. As opposed to evidence-based medicine, iridology is not supported by quality research studies and is widely considered pseudoscience. The features of the iris are one of the most stable features on the human body throughout life. The stability of iris structures is the foundation of the biometric technology which uses iris recognition for identification purposes. In 1979, Bernard Jensen, a leading American iridologist, and two other iridology proponents failed to establish the basis of their practice when they examined photographs of the eyes of 143 patients in an attempt to determine which ones had kidney impairments. Of the patients, forty-eight had been diagnosed with kidney disease, and the rest had normal kidney function. Based on their analysis of the patients' irises, the three iridologists could not detect which patients had kidney disease and which did not.
  • 6.2K
  • 04 Nov 2022
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