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OBJECTIVES: Genetic association studies on alopecia areata (AA) performed in various populations have shown heterogeneous results. The aim of the current review was to synthesize the results of said studies to estimate the impact of FAS, FASL, PTPN22, CTLA4 and IL2RA gene polymorphisms on AA susceptibility. DESIGN: A systematic literature search was conducted in the Medline, Web of Science, Scopus, EMBASE and LILACS databases. Studies published up to June 2020 were included. The results available in the grey literature including the Open Grey and Google Scholar databases were also used. The texts of potentially related studies were screened by individual reviewers. Evidence of publication bias was assessed using the Newcastle-Ottawa scale and the quality of evidence was assessed using the GRADE system. The quantitative synthesis was performed using the fixed effect model. RESULTS: Out of 1784 articles, we identified 18 relevant articles for the qualitative synthesis and 16 for the quantitative synthesis. In a study of rs2476601 polymorphism of PTPN22 gene, including 1292 cases and 1832 controls, a correlation was found with the risk of developing AA in the allelic model (OR1.49 [95% C:1.13-1.95]), the heterozygous codominant (OR1.44 [95% CI:1:19-1.76]) and dominant model (OR1.43 [95% CI:1.18-1.73]). No association was found between the presence of FASL, PTPN22, CTLA and IL2RA gene polymorphisms with AA susceptibility. CONCLUSIONS: The results suggest that the T allele of the single nucleoid polymorphism (SNP) rs2476601 in PTPN22 gene is a risk factor for developing alopecia areata. However, more robust studies defining the ethnic background of the population of origin are required, so that the risk identified in the present study can be validated. Additionally, a greater number of studies is necessary to evaluate the role of the FAS, FASL, PTPN22, CTLA4 and IL2RA genetic variants, given the heterogenous results found in the literature.

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BACKGROUND AND OBJECTIVE: The minimal erythema dose (MED), an essential measurement in studies of skin photosensitivity, requires establishing MED values for specific populations, given genetic variation. Different ways to assess erythema are also relevant. We aimed to determine MED values in a sample of Colombian patients and correlations between MED and Fitzpatrick skin type. We also studied concordance correlation between MEDs and two alternative ways to assess erythema. PATIENTS AND METHODS: Cross-sectional study of 113 individuals in Bogotá, Colombia. We used a solar simulator to measure UV-A radiation and combined UV-A and UV-B (UVA+UVB) radiation, o se podría suprimir este término porque UVA y UVB son términos conocidos for MED calculation. Narrowband UV-B (NBUVB) radiation was measured in a phototherapy cabin. Erythema was assessed visually and with a Mexameter MX 18 device. RESULTS: The median MEDs of UVA+UVB radiation were 22mJ/cm2 for Fitzpatrick skin typesI andII, and 33 and 43mJ/cm2, respectively, for typesIII andIV. The MEDs of UV-A radiation were 22, 42, 86, and 100J/cm2 for typesI, II, III, andIV, respectively. The MEDs of NBUVB light were 390, 550, 770, and 885mJ/cm2 for the 4 skin types. The correlation between MEDs and skin types ranged from 0.5 to 0.69. Lin's concordance correlation coefficients between visual and Mexameter assessments of erythema were greater than 0.8 in all cases. CONCLUSION: This study allowed us to understand MED values for UV-A, UVA+UVB, and NBUVB according to different skin types in the Colombian population. Concordance correlation coefficients between the different methods of erythema assessment were very good. Correlations between MEDs and skin types were moderate to good.

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BACKGROUND: Relapse rates in patients with acne after treatment with oral isotretinoin vary between 10% and 60% depending on the dosage regimen used, the length of follow-up, and the characteristics of the study population. The aim of this study was to determine the acne relapse rate within 2 years of completion of isotretinoin therapy and to identify the prognostic factors associated with relapse. MATERIAL AND METHODS: We studied a series of patients with cystic acne who had received a cumulative therapeutic dose of at least 120 mg/kg of oral isotretinoin. Data were analyzed using descriptive and analytical statistical methods. The relapse rate was expressed as the number of events divided by the amount of person-time. Factors predicting relapse were identified using multivariate Cox regression analysis. RESULTS: A total of 142 patients were followed up for 24 months or until relapse occurred. The relapse rate was 15 events per 100 person-years of follow-up. The risk of relapse was twice as high among men. The protective effect of maintenance treatment with topical retinoids was 32% for each month of use. The risk of relapse was 3.5 times higher among women not receiving antiandrogen therapy. CONCLUSIONS: The relapse rate in our study was high and similar to that reported in the literature, Maintenance treatment with topical retinoids in men and women and androgen treatment in women helped to prevent relapse.

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El lupus eritematoso sistémico (LES) es una enfermedad caracterizada por la pérdida de la tolerancia hacia antígenos propios que conlleva a la aparición de autoanticuerpos contra antígenos nucleares y daño de órganos asociado. Durante la apoptosis se expone al sistema inmune a múltiples antígenos nucleares y se piensa que alteraciones en la remoción de cuerpos apoptóticos pueden iniciar o perpetuar una respuesta autoinmune. Otra fuente de material nuclear expuesto al medio extracelular son las denominadas micropartículas, las cuales son liberadas de diferentes células no solo durante la apoptosis sino también durante la activación celular o el estrés mecánico. Se ha demostrado que los pacientes con LES presentan autoanticuerpos varios años antes de la fase clínica de la enfermedad, y esta aparición de autoanticuerpos tiende a seguir un curso predecible, con acumulación progresiva de autoanticuerpos específicos. Esta aparición consistentemente ordenada de autoanticuerpos, precediendo por varios años la aparición de la enfermedad clínica, apoya fuertemente las teorías de diseminación de epítopes en LES humano. Varios modelos múridos han tratado de reproducir la enfermedad humana utilizando cuerpos apoptóticos pero sin resultados contundentes. Un reciente modelo animal logra reproducir más fielmente la secuencia de autoanticuerpos y las manifestaciones clínicas del LES al utilizar a la β2GP-I como inmunógeno potenciado por una respuesta de célula T inducida por lipopolisacárido. Las micropartículas, rodeadas de fosfatidilserina y cargadas de material nuclear incluyendo DNA extracelular antigénicamente activo, son asimismo candidatas ideales para servir de plataforma para la diseminación de epítopes en un medio inflamatorio, con la posterior aparición secuencial de autoanticuerpos específicos patogénicos.

Systemic lupus erythematosus (SLE) is a disease characterized by loss of tolerance to self-antigens leading to the development of autoantibodies against nuclear antigens and organ damage. During apoptosis, immune system is exposed to multiple nuclear antigens and is thought that alterations in the removal of apoptotic bodies could start or perpetuate an autoimmune response. Another source of nuclear material exposed to extracellular medium are called microparticles, which are released from various cells not only during apoptosis but also during cell activation or mechanical stress. It has been shown that patients with SLE already have autoantibodies several years before clinical phase of disease, and this appearance of autoantibodies tends to follow a predictable course, with progressive accumulation of specific autoantibodies. This steadily orderly appearance of autoantibodies preceding for several years the onset of clinical disease strongly supports theories of spreading epitopes in human SLE. Several mouse models have tried to replicate the human disease using apoptotic bodies but without conclusive results. A recent animal model can reproduce more closely the sequence of autoantibodies and clinical manifestations of SLE using the β2-glycoprotein I (β2GP-I) as an immunogen powered by a lipopolysaccharide induced T cell response. Microparticles, surrouded by phosphatidylserie and nuclear material loaded including antigenically active extracellular DNA, are also ideal candidates to serve as a.

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A number of pathogenic microorganisms have been previously shown to bind plasminogen. The subsequent activation of plasminogen into plasmin can contribute to their virulence. In this study, we have shown that Streptococcus mutans is able to bind both human plasminogen and plasmin. Binding of plasminogen to S. mutans was inhibited by L-lysine and epsilon-aminocaproic acid, indicating that binding is mediated via lysine-binding sites of plasminogen. S. mutans enhanced the activation of plasminogen by tissue plasminogen activator but not by urokinase. This enhancement turned out to be dependent on cell concentration. Zymogram analysis showed that the plasmin activity acquired after plasminogen binding and activation is the most important proteolytic activity in the strain tested. These results suggest a mechanism involving acquisition of a host protease that might contribute to the infective process of this microorganism.

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OBJECTIVE: To investigate the usefulness of endoscopic gastrostomy and long-term complications. BACKGROUND DATA: Endoscopic gastrostomy is well established as the procedure of choice for long-term feeding, given the low morbidity-mortality and ease of placement. METHOD: We evaluated retrospectively one hundred endoscopically placed gastrostomy feeding tubes and complications occurring more than 30 days after placement were recorded. RESULTS: Gastrostomy feeding tubes remained in place for a mean of 92 days (range 30-547 days). Fifteen percent developed evident gastroesophageal reflux, two patients developed aspiration pneumonia and one presented with infection at the site of gastrostomy. Our long-term complications rate thus was 3.0% and 0% mortality. CONCLUSIONS: Our experience suggests that endoscopic gastrostomy is a relatively simple procedure, associated with very low morbidity and mortality. It is the procedure of choice in patients requiring long-term enteral nutrition.

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The World Health Organization (WHO) has indicated that opioid analgesics are insufficiently available, particularly in developing countries, due to a variety of reasons, including legislative, educational, and policy issues. In its effort to promote the rational use of medical opioids and the adequate treatment of patients with cancer, WHO has sponsored a meeting of Latin American representatives every 2 years, which includes health professionals and government regulators. During March 24-27, 1996, a group of 86 representatives of cancer pain relief and palliative care programs from nine Latin American countries met in Santo Domingo under the auspices of the WHO Palliative Care Program for Latin America. For the first time since the First Latin American Meeting, government regulators were present to help address the issue of opioid availability from their perspective. During the meeting, issues pertaining to cancer pain, opioid availability, and palliative care were discussed. This report summarizes some of the events and presents a summary of the conclusions of an earlier meeting in 1994, as described in the Declaration of Florianopolis, and presents its follow-up, The Santo Domingo Report, generated following the 1996 meeting.

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