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2.
Psychiatry ; 86(4): 278-298, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38149711

RESUMO

While mass panic (and/or violence) and self-preservation are often assumed to be the natural response to physical danger and perceived entrapment, the literature indicates that expressions of mutual aid are common and often predominate, and collective flight may be so delayed that survival is threatened. In fact, the typical response to a variety of threats and disasters is not to flee but to seek the proximity of familiar persons and places; moreover, separation from attachment figures is a greater stressor than physical danger. Such observations can be explained by an alternative "social attachment" model that recognizes the fundamentally gregarious nature of human beings and the primacy of attachments. In the relatively rare instances where flight occurs, the latter can be understood as one aspect of a more general affiliative response that involves escaping from certain situations and moving toward other situations that are perceived as familiar but which may not necessarily be objectively safe. The occurrence of flight-and-affiliation depends mainly on the social context and especially the whereabouts of familiar persons (i.e., attachment figures); their physical presence has a calming effect and reduces the probability of flight-and-affiliation, while their absence has the opposite effect. Combining the factors of perceived physical danger and the location of attachment figures results in a four-fold typology that encompasses a wide spectrum of collective responses to threat and disaster. Implications of the model for predicting community responses to terrorist attacks and/or use of weapons of mass destruction are briefly discussed.


Assuntos
Desastres , Terrorismo , Humanos , Violência
3.
Evol Appl ; 16(5): 963-978, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37216026

RESUMO

Human populations adapting to diverse aspects of their environment such as climate and pathogens leave signatures of genetic variation. This principle may apply to people of West Central African descent in the United States, who are at increased risk of certain chronic conditions and diseases compared to their European counterparts. Less well known is that they are also at reduced risk of other diseases. While discriminatory practices in the United States continue to affect access to and the quality of healthcare, the health disparities affecting African Americans may also be due in part to evolutionary adaptations to the original environment of sub-Saharan Africa, which involved continuous exposure to the vectors of potentially lethal endemic tropical diseases. Evidence is presented that these organisms selectively absorb vitamin A from the host, and its use in parasite reproduction contributes to the signs and symptoms of the respective diseases. These evolutionary adaptations included (1) sequestering vitamin A away from the liver to other organs, to reduce accessibility to the invaders; and (2) reducing the metabolism and catabolism of vitamin A (vA), causing it to accumulate to subtoxic concentrations and weaken the organisms, thereby reducing the risk of severe disease. However, in the environment of North America, lacking vA-absorbing parasites and with a mainly dairy-based diet that is high in vA, this combination of factors is hypothesized to lead to the accumulation of vA and to increased sensitivity to vA as a toxin, which contribute to the health disparities affecting African Americans. vA toxicity is linked to numerous acute and chronic conditions via mitochondrial dysfunction and apoptosis. Subject to testing, the hypothesis suggests that the adoption of traditional or modified West Central African-style diets that are low in vA and high in vA-absorbing fiber hold promise for disease prevention and treatment, and as a population-based strategy for health maintenance and longevity.

4.
Viral Immunol ; 34(6): 376-379, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33983857

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has a marked tropism for the biliary tract; it damages the bile ducts and hepatocytes and can lead to liver decompensation, cirrhosis, and sepsis. The pathogenesis of liver damage and its association with damage to the lung, heart, and brain and to the other protean manifestations of COVID-19 disease are not fully understood. In particular, tissue damage from thinning and leaky blood vessels appears to result from an inflammatory response to the virus rather than the virus itself. This article outlines a new hypothesis of the nature of the inflammatory factor responsible for tissue damage in COVID-19. Review of the literature reveals that COVID-19 disease closely resembles an endogenous form of hypervitaminosis A. We propose that SARS-CoV-2 virus-induced liver damage causes retinoic acid and stored retinyl esters to be released into the circulation in toxic concentrations, unbound to protein, with resulting damage to organs including the lungs, heart, blood vessels, and skin. Several lines of evidence support this model of disease causation. Subject to testing, strategies for the effective treatment and prevention of COVID-19 could include targeting the action and accumulation of retinoids.


Assuntos
COVID-19/etiologia , Hepatopatias/etiologia , Retinoides/toxicidade , SARS-CoV-2 , Corticosteroides/uso terapêutico , Humanos , Cirrose Hepática/etiologia , Hepatopatia Gordurosa não Alcoólica/etiologia
5.
Vaccines (Basel) ; 8(4)2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33198395

RESUMO

A growing number of vaccines are administered at the same time or in close succession, increasing the complexity of assessing vaccine safety. Individual vaccines are assumed to have no other effect than protection against the targeted pathogen, but vaccines also have nonspecific and interactive effects, the outcomes of which can be beneficial or harmful. To date, no controlled trials and very few observational studies have determined the impact of vaccination schedules on overall health. The balance of the risks and benefits from mass vaccination therefore remains uncertain. Recent studies worryingly suggest links between multiple vaccinations and increased risks of diverse multisystem health problems, including allergies, infections, and neuropsychiatric or neurodevelopmental disorders. Here, we propose that, in susceptible persons, multiple vaccinations activate the retinoid cascade and trigger apoptotic hepatitis, leading to cholestatic liver dysfunction, in which stored vitamin A compounds (retinyl esters and retinoic acid) enter the circulation in toxic concentrations; this induces endogenous forms of hypervitaminosis A, with the severity of adverse outcomes being directly proportional to the concentration of circulating retinoids. In very low concentrations, vitamin A and its major metabolite retinoic acid contribute to immune function and to the process of immunization, whereas excess vitamin A increases the risk of adverse events, including common "side-effects" as well as chronic adverse outcomes. The increasing rates of allergy, ear infections, and neurodevelopmental disorders (NDDs) in countries with high rates of vaccination could be related to mass vaccination and to its impact on liver function and vitamin A metabolism, collectively representing endogenous manifestations of hypervitaminosis A. Further studies of health outcomes in vaccinated and unvaccinated groups are urgently needed, to increase understanding of the pathophysiology and treatment of vaccine injury, to identify the risk factors and screen for vaccine injury, to inform public health policy on potential hazards related to vaccination schedules, and to optimize the safety and benefits of vaccines.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31546693

RESUMO

Rubella is a systemic virus infection that is usually mild. It can, however, cause severe birth defects known as the congenital rubella syndrome (CRS) when infection occurs early in pregnancy. As many as 8%-13% of children with CRS developed autism during the rubella epidemic of the 1960s compared to the background rate of about 1 new case per 5000 children. Rubella infection and CRS are now rare in the U.S. and in Europe due to widespread vaccination. However, autism rates have risen dramatically in recent decades to about 3% of children today, with many cases appearing after a period of normal development ('regressive autism'). Evidence is reviewed here suggesting that the signs and symptoms of rubella may be due to alterations in the hepatic metabolism of vitamin A (retinoids), precipitated by the acute phase of the infection. The infection causes mild liver dysfunction and the spillage of stored vitamin A compounds into the circulation, resulting in an endogenous form of hypervitaminosis A. Given that vitamin A is a known teratogen, it is suggested that rubella infection occurring in the early weeks of pregnancy causes CRS through maternal liver dysfunction and exposure of the developing fetus to excessive vitamin A. On this view, the multiple manifestations of CRS and associated autism represent endogenous forms of hypervitaminosis A. It is further proposed that regressive autism results primarily from post-natal influences of a liver-damaging nature and exposure to excess vitamin A, inducing CRS-like features as a function of vitamin A toxicity, but without the associated dysmorphogenesis. A number of environmental factors are discussed that may plausibly be candidates for this role, and suggestions are offered for testing the model. The model also suggests a number of measures that may be effective both in reducing the risk of fetal CRS in women who acquire rubella in their first trimester and in reversing or minimizing regressive autism among children in whom the diagnosis is suspected or confirmed.


Assuntos
Transtorno Autístico/induzido quimicamente , Hipervitaminose A/complicações , Hepatopatias/complicações , Síndrome da Rubéola Congênita/induzido quimicamente , Rubéola (Sarampo Alemão)/fisiopatologia , Vitamina A/toxicidade , Humanos , Hipervitaminose A/induzido quimicamente , Fígado/metabolismo , Vírus da Rubéola/fisiologia , Vitamina A/metabolismo
7.
Int J Adolesc Med Health ; 32(5)2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31532751

RESUMO

Although rates have decreased 8% since 2014, teen pregnancy remains a substantial public health and social problem in Mississippi and elsewhere in the US. Evidence suggests that, among teenagers, the after-school hours from 3 to 6 pm are peak times of risky sexual activity. This paper reviews recent research and programs concerning sexual risk behavior among adolescents and proposes that after-school programs would increase the daily period of supervised activity and thereby reduce risks not only of pregnancy and sexually transmitted diseases but would also serve to enhance scholastic attainment and hence career prospects for the future. After-school programs from 3 to 6 p.m. should incorporate a multifaceted model that includes academic enhancement and recreational activities as well as curriculum-based sex education, youth development, and service learning.


Assuntos
Gravidez na Adolescência/prevenção & controle , Serviços de Saúde Escolar/organização & administração , Educação Sexual , Adolescente , Feminino , Necessidades e Demandas de Serviços de Saúde , Humanos , Mississippi , Gravidez , Fatores de Risco
9.
Artigo em Inglês | MEDLINE | ID: mdl-30609834

RESUMO

An estimated 25%⁻32% of veterans of the 1991 Gulf War continue to experience multiple unexplained health problems known as Gulf War Illness (GWI). GWI encompasses chronic pain, musculoskeletal weakness, headache, fatigue, cognitive deficits, alterations in mood, and numerous multi-system complaints. Most potential exposures implicated in GWI were not well documented but included varying levels of several neurotoxicants as well as the anticholinergic drug pyridostigmine bromide (PB), which was routinely taken as prophylaxis against the nerve agent soman. While some veterans also took chloroquine as an antimalarial agent, the literature suggests an association between receipt of multiple vaccinations prior to or during the conflict (perhaps combined with other exposures), and GWI. In-theater exposures may account for any single individual veteran's ill health but many veterans of the same era who were not deployed overseas also suffer the same or similar symptoms. The features of GWI also overlap with those of fibromyalgia, chronic fatigue syndrome and multiple chemical sensitivity, in all of which liver dysfunction has been documented, suggesting a unifying hypothesis. It is proposed that multiple vaccinations, with concurrent or subsequent exposure to PB or additional chemical insults of a liver-damaging nature, plausibly explain the pathogenesis and the observed chronicity of GWI. The suggested mechanism for GWI is thus a chemically-induced impaired liver function, with the spillage of stored vitamin A compounds ("retinoids") into the circulation in toxic concentrations, resulting in an endogenous chronic form of hypervitaminosis A. Implications of the hypothesis are briefly reviewed.


Assuntos
Síndrome do Golfo Pérsico/etiologia , Inibidores da Colinesterase/efeitos adversos , Exposição Ambiental , Humanos , Brometo de Piridostigmina/efeitos adversos , Vacinação/efeitos adversos , Veteranos
10.
Diseases ; 6(4)2018 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-30384469

RESUMO

OBJECTIVE: This study among 400 undergraduate students enrolled at Jackson State University (JSU) study aimed to assess knowledge about HIV and AIDS among African-American undergraduate students attending a historically black college and university. A cross-sectional survey was conducted. Data were collected using a validated, self-administered, and standardized questionnaire on knowledge regarding risks for HIV and AIDS. Three hundred and eighty-six students (96.5%) had good knowledge about HIV and AIDS, although some participants had misconceptions about the modes of HIV infection transmission. There were no significant gender differences for HIV and AIDS knowledge among the participants (χ² = 3.05; P = 0.08). In general we concluded that JSU undergraduate students had adequate knowledge about HIV transmission modes and AIDS, although some participants had misconceptions about the routes of HIV infection transmission. Hence, this study calls for strengthening HIV and AIDS awareness education among undergraduate students.

11.
J Caring Sci ; 7(1): 1-8, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29637050

RESUMO

Introduction: Depression is a major public health issue. One of the concerns in depression research and practice pertains to non-compliance to prescribed medications. The purpose of the study was to predict compliance with medication use for patients with depression using social cognitive theory (SCT). Based on this study it was envisaged that recommendations for interventions to enhance compliance for medication use could be developed for patients with depression. Methods: The study was conducted using cross sectional design (n=148) in southern United States with a convenience sample of clinic-based depression patients with a 37-item valid and reliable questionnaire. Sample size was calculated to be 148 using G*Power (five predictors with a 0.80 power at the 0.05 alpha level and an estimated effect size of 0.10 with an inflation by 10% for missing data). Social cognitive theory constructs of expectations, self-efficacy and self-efficacy in overcoming barriers, self-control, and environment were reified. Data were analyzed using multiple linear regression and multiple logistic regression analyses. Results: Self-control for taking medication for depression (P=0.04), expectations for taking medication for depression (P=0.025), age (P<0.0001) and race (P=0.04) were significantly related to intent for taking medication for depression (Adjusted R2 = 0.183). In race, Blacks had lower intent to take medication for depression. Conclusion: Social cognitive theory is weakly predictive with low explained variance for taking medication for depression. It needs to be bolstered by newer theories like integrative model or multi-theory model of health behavior change for designing educational interventions aimed at enhancing compliance to medication for depression.

13.
Int J Cancer ; 141(9): 1849-1855, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28707393

RESUMO

A geographical and causal connection has long been recognized between malaria, Epstein-Barr virus (EBV) infection and Burkitt's lymphoma (BL), but the underlying mechanisms remain obscure. Potential clues are that the malaria parasite Plasmodium falciparum selectively absorbs vitamin A from the host and depends on it for its biological activities; secondly, alterations in vitamin A (retinoid) metabolism have been implicated in many forms of cancer, including BL. The first author has proposed that the merozoite-stage malaria parasite, emerging from the liver, uses its absorbed vitamin A as a cell membrane destabilizer to invade the red blood cells, causing anemia and other signs and symptoms of the disease as manifestations of an endogenous form of hypervitaminosis A (Mawson AR, Path Global Health 2013;107(3):122-9). Repeated episodes of malaria would therefore be expected to expose the tissues of affected individuals to potentially toxic doses of vitamin A. It is proposed that such episodes activate latent EBV infection, which in turn activates retinoid-responsive genes. Expression of these genes enhances viral replication and induces germinal center (GC) B cell expansion, activation-induced cytidine deaminase (AID) expression, and c-myc translocation, which in turn predisposes to BL. Thus, an endogenous form of retinoid toxicity related to malaria infection may be the common factor linking frequent malaria, EBV infection and BL, whereby prolonged exposure of lymphatic tissues to high concentrations of retinoids may combine to induce B-cell translocation and increase the risk of Burkitt's lymphoma.


Assuntos
Linfoma de Burkitt/parasitologia , Linfoma de Burkitt/virologia , Infecções por Vírus Epstein-Barr/metabolismo , Malária Falciparum/metabolismo , Linfócitos B/metabolismo , Linfócitos B/parasitologia , Linfócitos B/patologia , Linfócitos B/virologia , Linfoma de Burkitt/complicações , Linfoma de Burkitt/metabolismo , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/patogenicidade , Humanos , Malária Falciparum/complicações , Malária Falciparum/parasitologia , Malária Falciparum/virologia , Plasmodium falciparum/patogenicidade , Vitamina A/metabolismo
14.
Trop Med Infect Dis ; 2(3)2017 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-30270893

RESUMO

More than a billion people-one-sixth of the world's population, mostly in developing countries-are infected with one or more of the neglected tropical diseases (NTDs). Several national and international programs (e.g., the World Health Organization's Global NTD Programs, the Centers for Disease Control and Prevention's Global NTD Program, the United States Global Health Initiative, the United States Agency for International Development's NTD Program, and others) are focusing on NTDs, and fighting to control or eliminate them. This review identifies the risk factors of major NTDs, and describes the global burden of the diseases in terms of disability-adjusted life years (DALYs).

15.
Infect Dis (Auckl) ; 10: 1178633617731741, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29317828

RESUMO

Based on the observation that the parasite Onchocerca volvulus selectively absorbs vitamin A from the host, and the known toxicity of vitamin A in higher concentration, it was hypothesized that dying microfilariae (mf) release their stores of vitamin A (retinoids) into the host circulation in toxic concentrations, inducing the signs and symptoms of onchocerciasis. We conducted a pilot study to test the hypothesis in Songea communities in Southern Tanzania, where mass drug administration with ivermectin had not been implemented by the time of the survey. The specific aim was to evaluate the correlation between the diagnosis of onchocerciasis and increased levels of retinoic acid at infection sites. The analysis was performed by determining copy numbers of a genome of O volvulus present in skin snip samples of persons with onchocerciacis, and correlating these numbers with expression levels of retinoic acid receptor-α (RAR-α), which is inducible by retinoic acid. Total DNA and RNA were extracted from each of 25 mf-positive and 25 mf-negative skin samples and evaluated using quantitative polymerase chain reaction with appropriate negative controls. Analysis of the samples, adjusted with glyceraldehyde 3-phosphate dehydrogenase gene levels, revealed that most samples with detectable RAR-α transcripts had higher levels of RAR-α expression than the assay control. However, the quality and number of samples were insufficient for statistical analysis. Fold data on the expression levels of both O volvulus DNA and RAR RNA suggested a possible trend toward higher relative RAR-α expression in samples with higher levels of O volvulus DNA ( r2 = 0.25, P = .079). Evidence of a contribution of vitamin A to the pathology of onchocerciasis thus remains elusive. Future studies on the role of retinoids in onchocerciasis will require larger groups of participants as well as careful monitoring of the cold chain and tissue storage procedures in view of the sensitivity of vitamin A to heat and light.

16.
Eur Neurol ; 76(5-6): 244-251, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27750253

RESUMO

Stuttering affects about 1% of the general population and from 8 to 11% of children. The onset of persistent developmental stuttering (PDS) typically occurs between 2 and 4 years of age. The etiology of stuttering is unknown and a unifying hypothesis is lacking. Clues to the pathogenesis of stuttering include the following observations: PDS is associated with adverse perinatal outcomes and birth-associated trauma; stuttering can recur or develop in adulthood following traumatic events such as brain injury and stroke; PDS is associated with structural and functional abnormalities in the brain associated with speech and language; and stuttering resolves spontaneously in a high percentage of affected children. Evidence marshaled from the literature on stuttering and from related sources suggests the hypothesis that stuttering is a neuro-motor disorder resulting from perinatal or later-onset hypoxic-ischemic injury (HII), and that chronic stuttering and its behavioral correlates are manifestations of recurrent transient ischemic episodes affecting speech-motor pathways. The hypothesis could be tested by comparing children who stutter and nonstutterers (controls) in terms of the occurrence of perinatal trauma, based on birth records, and by determining rates of stuttering in children exposed to HII during the perinatal period. Subject to testing, the hypothesis suggests that interventions to increase brain perfusion directly could be effective both in the treatment of stuttering and its prevention at the time of birth or later trauma.


Assuntos
Encéfalo/fisiopatologia , Gagueira/fisiopatologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino
17.
J Transl Sci ; 2(3): 154-159, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27595011

RESUMO

Neither the mechanisms of parturition nor the pathogenesis of preterm birth are well understood. Poor nutritional status has been suspected as a major causal factor, since vitamin A concentrations are low in preterm infants. However, even large enteral doses of vitamin A from birth fail to increase plasma concentrations of vitamin A or improve outcomes in preterm and/or extremely low birthweight infants. These findings suggest an underlying impairment in the secretion of vitamin A from the liver, where about 80% of the vitamin is stored. Vitamin A accumulates in the liver and breast during pregnancy in preparation for lactation. While essential in low concentration for multiple biological functions, vitamin A in higher concentration can be pro-oxidant, mutagenic, teratogenic and cytotoxic, acting as a highly surface-active, membrane-seeking and destabilizing compound. Regarding the mechanism of parturition, it is conjectured that by nine months of gestation the hepatic accumulation of vitamin A (retinol) from the liver is such that mobilization and secretion are impaired to the point where stored vitamin A compounds in the form of retinyl esters and retinoic acid begin to spill or leak into the circulation, resulting in amniotic membrane destabilization and the initiation of parturition. If, however, the accumulation and spillage of stored retinoids reaches a critical threshold prior to nine months, e.g., due to cholestatic liver disease, which is common in mothers of preterm infants, the increased retinyl esters and/or retinoic acid rupture the fetal membranes, inducing preterm birth and its complications, including retinopathy, necrotizing enterocolitis and bronchopulmonary dysplasia. Subject to testing, the model suggests that measures taken prior to and during pregnancy to improve liver function could reduce the risk of adverse birth outcomes, including preterm birth.

18.
Biores Open Access ; 5(1): 171-6, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27403405

RESUMO

A strong causal association has become evident between Zika virus (ZIKV) infection during pregnancy and the occurrence of fetal growth restriction, microcephaly and eye defects. Circumstantial evidence is presented in this paper in support of the hypothesis that these effects, as well as the Guillain-Barré syndrome, are due to an endogenous form of hypervitaminosis A resulting from ZIKV infection-induced damage to the liver and the spillage of stored vitamin A compounds ("retinoids") into the maternal and fetal circulation in toxic concentrations. Retinoids are mainly stored in the liver (about 80%) and are essential for numerous biological functions. In higher concentration, retinoids are potentially cytotoxic, pro-oxidant, mutagenic and teratogenic, especially if sudden shifts occur in their bodily distribution. Although liver involvement has not been mentioned specifically in recent reports, conventional liver enzyme tests underestimate the true extent of liver dysfunction. The proposed model could be tested by comparing retinoid concentration and expression profiles in microcephalic newborns of ZIKV-infected mothers and nonmicrocephalic newborn controls, and by correlating these profiles with measures of clinical severity.

19.
J Appl Res Intellect Disabil ; 29(3): 211-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-25832547

RESUMO

BACKGROUND: Low-and middle-income countries (LAMI) lack an integrated and systematic approach to identify people with intellectual disabilities. Screening surveys are considered resource-intensive; therefore, alternative approaches are needed. This study attempted to identify children up to age 18 years with intellectual disabilities through a mixed-method approach involving focus group interviews (FGIs) and door-to-door surveys. MATERIALS AND METHODS: Focus groups were conducted with the assistance and involvement of local leaders in four villages of Barwani district of Madhya Pradesh with a 99% tribal population in all four villages. A formal survey of the community was then conducted to determine the prevalence of intellectual disabilities based on a standardized screening instrument (NIMH-DDS). RESULTS: Thirty focus group interviews were conducted involving 387 participants (males 284, females 103) over a period of 13 days. The entire adult population (N = 8797) was then surveyed for intellectual disabilities using a standardized screening instrument. The data revealed a close similarity in the prevalence rates of intellectual disabilities, as determined by the two approaches (Focus Group Interviews, 5.22/1000 versus Survey, 5.57/1000). CONCLUSION: A qualitative method using FGIs successfully identified people with intellectual disabilities in an economically deprived tribal area, showing that a community-based approach provides a close estimate of intellectual disabilities based on a formal survey using standard diagnostic criteria. These data suggest that FGI, along with other qualitative data, could be helpful in designing and in serving as an entree for community-based interventions.


Assuntos
Inquéritos Epidemiológicos/métodos , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/etnologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Índia/etnologia , Masculino , População Rural
20.
Med Sci Monit ; 21: 133-43, 2015 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-25579087

RESUMO

Stevens-Johnson syndrome and toxic epidermal necrolysis (SJS/TEN) are overlapping manifestations on a spectrum of acute drug-induced conditions associated with severe blistering, skin peeling, and multi-organ damage. TEN is an eruption resembling severe scalding, with ≥30% skin detachment. SJS is a mild form of TEN, characterized histologically by epidermal keratinocyte apoptosis with dermo-epidermal separation and extensive small blisters with <10% body surface skin detachment. The syndrome can be induced by numerous medications and typically occurs 1-4 weeks after the initiation of therapy. Granulysin is found in the lesions of patients with SJS/TEN and plays a significant pathogenic role in the condition, but the overall mechanisms linking medications, granulysin, and disease manifestations remain obscure. This paper reviews evidence suggesting that the different medications implicated in SJS/TEN have the common property of interacting and synergizing with endogenous retinoids (vitamin A and its congeners), in many instances causing the latter to accumulate in and damage the liver, the main storage organ for vitamin A. It is hypothesized that liver damage leads to the spillage of toxic retinoid compounds into the circulation, resulting in an endogenous form of hypervitaminosis A and cytotoxicity with widespread apoptosis, mediated by granulysin and recognized as SJS/TEN. Subject to testing, the model suggests that symptom worsening could be arrested at onset by lowering the concentration of circulating retinoids and/or granulysin via phlebotomy or plasmapheresis or by pharmacological measures to limit their expression.


Assuntos
Retinoides/efeitos adversos , Síndrome de Stevens-Johnson/etiologia , Antibacterianos/efeitos adversos , Anti-Inflamatórios não Esteroides/efeitos adversos , Antifúngicos/efeitos adversos , Antígenos de Diferenciação de Linfócitos T/metabolismo , Apoptose , Colestase/fisiopatologia , Epiderme/metabolismo , Humanos , Hipervitaminose A/metabolismo , Queratinócitos/citologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Retinoides/química , Pele/efeitos dos fármacos , Vitamina A/química
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