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Despite being little explored for petroporphyrins recovery from oils and bituminous shales, adsorption and desorption processes can be feasible alternatives to obtain a similar synthetic material, and to characterize their original organic materials. Experimental designs were used to analyze the effects of qualitative (e.g., type of adsorbent, solvent, and diluent) and quantitative (e.g., temperature and solid/liquid ratio) variables on the adsorptive and desorptive performance regarding nickel octaethylporphyrin (Ni-OEP) removal using carbon-based adsorbents. The evaluation variables, adsorption capacity (qe ) and desorption percentage (%desorption ) were optimized by means of the Differential Evolution algorithm. The most efficient adsorbent for removing/recovery Ni-OEP was activated-carbon coconut shell, in which dispersive π-π type and acid-base interactions were likely formed. The highest values of qe and %desorption were obtained using toluene as solvent, chloroform as diluent, 293 K as temperature, and 0.5 mg.mL-1 as solid/liquid ratio for adsorption, and a higher temperature (323 K) and lower solid/liquid ratio (0.2 mg.mL-1) for desorption. The optimization process resulted in qe of 6.91 mg.g-1 and %desorption of 35.2%. In the adsorption-desorption cycles, approximately 77% of the adsorbed porphyrins were recovered. The results demonstrated the potential of carbon-based materials as adsorbent materials for obtaining porphyrin compounds from oils and bituminous shales.
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Níquel , Porfirinas , Carbono , Adsorção , Excipientes , SolventesRESUMO
Despite being subject to lower AIDS-related mortality rates and having a higher life expectancy, patients with HIV are more prone to develop non-AIDS events. A low CD4+/CD8+ ratio during antiretroviral therapy identifies people with heightened immune senescence and increased risk of mortality. In clinical practice, finding determinants of a low CD4+/CD8+ ratio may be useful for identifying patients who require close monitoring due to an increased risk of comorbidities and death. We performed a prospective study on the evolution of the CD4+/CD8+ ratio in 60 patients infected with HIV (80% males), who were subjected to two different antiretroviral regimens: early and deferred therapy. The initial CD4+/CD8+ ratio was ≤1 for 70% of the patients in both groups. Older age, CD4+ cell count at inclusion, Nadir CD8+T-cell count, and Initial CD4+/CD8+ ratio ≤ 1 were risk factors for lack of ratio recovery. In the multivariate analysis, a CD4+/CD8+ ratio > 1 at the start of the treatment was found to be a determinant factor in maintaining a CD4+/CD8+ ratio > 1. The nadir CD4+T-cell count was lower in the deferred therapy group (p=0.004), and the last CD4+/CD8+ ratio ≤1 was not associated with comorbidities. Ratio recovery was not associated with the duration of HIV infection, time without therapy, or absence of AIDS incidence. A greater improvement was observed in patients treated early (p=0.003). In contrast, the slope of increase was slower in patients who deferred treatment. In conclusion, the increase in the CD4+/CD8+ ratio occurred mostly for patients undergoing early strategy treatment and its extension did not seem to be related to previous HIV-related factors.
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Síndrome da Imunodeficiência Adquirida , Fármacos Anti-HIV , Infecções por HIV , Masculino , Humanos , Feminino , Infecções por HIV/complicações , Estudos Prospectivos , Terapia Antirretroviral de Alta Atividade , Linfócitos T CD8-Positivos , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos , Fármacos Anti-HIV/uso terapêutico , Carga ViralRESUMO
Background: Klinefelter syndrome (KS), which is related to the presence of an additional X chromosome in a man, is associated with a broad variety of physical and psychosocial impairments. While the focus is usually placed on symptoms related to hypogonadism, such as infertility, recent studies have noted evidence of poor sleep in those patients. Case Description: We report on the case of a 44-year-old man with KS who consulted in our Sleep medicine center for excessive daytime sleepiness and delayed sleep with irregular patterns. Polysomnography (PSG) revealed sleep apnea syndrome, with both obstructive and central apnea. Peripheral temperature monitoring revealed patterns indicative of altered melatonin secretion. The present case report suggests that sleep disturbance in patients with KS appears multifactorial with the occurrence of: obstructive sleep apnea (OSA), iatrogenic central apnea due to testosterone therapy, and circadian sleep/wake disorder. Conclusions: While this topic warrants larger studies with control groups, this case report suggests there might be specific sleep impairments, associated with three different mechanisms, in patients with KS. Those sleep disorders can worsen psycho-social and cognitive difficulties in those patients, and should therefore be screened for and treated.
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INTRODUCTION: While COVID-19 is predominantly considered to be an acute self-remitting disease, it has been pointed out that a variety of symptoms can linger for several months, a phenomenon identified as long-COVID. Insomnia is particularly prevalent in long-COVID. In the present study, we aimed at confirming and characterising insomnia in long-COVID patients through polysomnography and to identify whether its parameters differ from patients with chronic insomnia and no long-COVID history. MATERIALS AND METHODS: We conducted a case-control study, including 17 long-COVID patients with insomnia symptoms (cases), and 34 2:1 matched controls with a diagnostic of chronic insomnia and no history of long-COVID. All underwent a one-night polysomnography (PSG). RESULTS: First, we observed that long-COVID patients with insomnia complaints have altered PSG parameters, in favour of the diagnosis of chronic insomnia. Second, we show that insomnia related to long-COVID PSG parameters was not significantly different from regular chronic insomnia PSG parameters. DISCUSSION: Our results indicate that even though it is one of the most prevalent symptoms of long-COVID, its related insomnia resembles typical chronic insomnia, based on PSG studies. Even though additional studies are warranted, our results suggest that the pathophysiology and therapeutic options should be similar to those recommended for chronic insomnia.
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COVID-19 , Distúrbios do Início e da Manutenção do Sono , Humanos , COVID-19/complicações , Estudos de Casos e Controles , Síndrome de COVID-19 Pós-AgudaRESUMO
Study Objectives: This exploratory study assessed the impact of sex and hormonal contraceptives (HC) use on the homeostatic and diurnal variation of alertness, fatigue, sleepiness, psychomotor performance, and sleep behavior in police officers working rotating shifts. Methods: A total of 56 men and 20 women (6 using, 11 not using, and 3 with unknown use of HC) participated in an observational study throughout a month-long work cycle. Participants wore an actigraph, filled out a sleep and work log, answered questionnaires (Samn-Perelli, KSS, Visual Analogue Scales), and completed 5-min Psychomotor Vigilance Tasks (PVT) according to an ecological momentary assessment approach. Linear mixed-effects models were used to analyze the effects of group (men, women, and HC use), time awake, and time of day on the dependent variables. Results: Self-reported parameters and performance significantly varied with time awake and time of day. Women were more fatigued and sleepier than men, when considering both time awake and time of day. Compared to men, women using HC were more fatigued, less alert, and sleepier. Women had less attention lapses than men after 7 and 17 h awake, although no main effect of HC was detected. Conclusions: Women tended to rate themselves as more fatigued than men, especially when using HC. Surprisingly, psychomotor performances of women were sometimes better than those of men. This exploratory study indicates that sex and HC are important factors to consider in occupational medicine.
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Soil fulfils vital functions for life on Earth and so, just like water and air, its protection from all sources of contamination is a major concern. However, the extensive use of petroleum derived products, either as energy sources or as commodities, leads to important environmental liabilities. Ex situ soil washing is a technology to concentrate contaminants, allowing soil cleaning and the reuse of extracted petroleum derived products. This work focuses on the optimization of ex situ soil washing process using surfactants, introducing an evaluation of the washing solution recycling and its after use safe disposal, promoting the reduction of raw materials, energy and water resources costs. Two surfactants, sodium dodecyl sulphate (SDS) and polyoxyethylene sorbitan monooleate (Tween 80), were tested in the decontamination of an artificially contaminated soil with engine lubricant oil waste. The optimization of the washing conditions, such as stirring speed, liquid-solid ratio, number of washing stages, and surfactant concentration, was carried out using a design of experiments (DOE) software, so that the maximum extraction efficiency of total petroleum hydrocarbons (TPHs) was achieved. A TPH removal efficiency of (80.7 ± 3.2)% was obtained with Tween 80 after 5â h of washing and (90.7 ± 2.8)% with SDS after 2â h at 200â rpm on an orbital shaker with a liquid to solid ratio (L/S) of 15. The potential for reuse of the washing solutions was evaluated. Finally, the discharge of the washing solution was considered using activated carbon to remove the surfactants and ensure its safe disposal.
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Background: This study aimed to compare two-dimensional radiographs and cone beam computed tomography (CBCT) images for mini-implant planning. Material and Methods: A search was performed in PubMed, Embase, Web of Science, Cochrane Library and Google Scholar electronic databases according to PIRD strategy, on September 11, 2021. In vivo studies that compared two-dimensional imaging with CBCT for mini-implant planning were selected. The methodological quality of each study was assessed using the QUADAS-2 tool. Results: The initial search identified 441 papers. Five studies were added following a manual research. Of the total 446 studies, 40 were selected after title evaluation, 29 remained after abstract evaluation, and 11 were left after full-text analysis. Final screening yielded a total of four studies that composed the narrative synthesis of this systematic review. When comparing the imaging systems for palatal mini-implants, lateral radiographs (LRs) showed approximately the same measurements of bone quantity as those of CBCT, hence bearing no influence on placement site selection. In determining image suitability for interradicular mini-implants, two-dimensional radiographs underestimated the available space. Conclusions: Lateral radiography is sufficient to quantify the available bone for planning mini-implants installed on the palate, in the median region of upper first premolars. CBCT enhances interradicular mini-implant planning by aiding in implantation site selection, and improving the installation success rate. Key words:Systematic Review, Cone beam computed tomography, Radiography, Orthodontic mini-implant, Dental planning.
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OBJECTIVE: To evaluate the association of sleep parameters on female and male reproductive functions. DESIGN: Systematic review. SETTING: Not applicable. PATIENT(S): Female and male individuals, either healthy or infertile. INTERVENTION(S): Relevant articles were identified according to the The Preferred Reporting Items for Systematic Reviews and Meta-analyses recommendations in the PubMed and EMBASE databases from January 1, 2000 to June 8, 2020. MAIN OUTCOME MEASURE(S): The association between sleep and ovary function, spermatic function, natural fertility, and in vitro fertilization (IVF) outcomes was assessed. RESULT(S): A total of 33 studies that looked at the association between sleep and either ovary function (n = 10), spermatic function (n = 12), natural fertility (n = 5), or IVF outcomes (n = 6) were included. Overall, female and male fertility, as well as IVF outcomes may be affected by short sleep duration, evening chronotype, or shift/night work schedules. However, the results were hardly comparable due to the heterogeneous study methodologies used. CONCLUSION(S): Sleep may be an original and innovative parameter to consider in the reproduction field. Further investigation is needed to elucidate how sleep and fertility are interrelated and how sleep might constitute a useful modifiable target in infertility management.
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Fertilidade/fisiologia , Infertilidade/epidemiologia , Técnicas de Reprodução Assistida/tendências , Privação do Sono/epidemiologia , Sono/fisiologia , Feminino , Humanos , Infertilidade/etiologia , Infertilidade/fisiopatologia , Masculino , Privação do Sono/complicações , Privação do Sono/fisiopatologiaRESUMO
Real-world data (RWD) and real-world evidence (RWE) appear now as complementary to traditional randomized controlled trials (RCT), that remain the gold standard of the evidence. This review aims to illustrate how health authorities in France, United States (USA) and United Kingdom (UK) can integrate RWD and RWE in market authorization discussions and in new pathways of price and reimbursement negotiations. We conducted a review from the literature, online investigations and interviews. RWD and RWE can be valuable in the context of market access, reimbursement decisions, price negotiation, pharmacovigilance and positive patient outcomes. While RWD could open new areas of innovative approaches and improve the efficiency of health systems, they have methodological limitations requiring further analysis to reach a sufficient level of proof. Moreover, misleading use of "RWD" and "RWE" terms is very frequent and even the definitions used by stakeholders (when they have one) are heterogenous. Because of the intrinsic characteristics of each product, the value given to these RWD may differ a lot, making them a useful tool more than an indispensable one. In sum, RWD and, more precisely, RWE have the potential to bring value to the health system at every step of the drug development process, from the discovery to the pharmacovigilance phase.
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Negociação , Humanos , Reino Unido , Estados UnidosRESUMO
Objectives.To optimize the absorbed organ dose in relation to the field of view for temporomandibular joint examinations in four cone beam computed tomography devices.Methods.An anthropomorphic adult head and neck phantom, and 192 LiF dosimeters (TLD-100) were used. The dosimeters were placed in the region corresponding to the lens, parotid glands, submandibular glands, and thyroid. Small, medium and large FOVs were selected on Orthopantomograph OP300 Maxio, PaX-i3D Smart, ORTHOPHOS XG, and i-CAT Next Generation device when it was possible.Results.A wide range of absorbed dose values was recorded for all organs due to the different exposure parameters of each device. The radiosensitive organ with the highest dose was the parotid glands. The devices with 5 × 5 cm FOV recorded a lower dose in this protocol, while for the device without a small FOV (≤5 × 5 cm), the lowest dose was observed with the large FOV (6 × 16 cm).Conclusions.We recommend a double exposure with an FOV of 5 × 5 cm in the OP300 Maxio, PaX-i3D Smart, and ORTHOPHOS XG device, while in the i-CAT Next Generation device, a single exposure FOV of 6 × 16 cm is indicated.
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Tomografia Computadorizada de Feixe Cônico , Dosimetria Termoluminescente , Doses de Radiação , Radiometria , Articulação Temporomandibular/diagnóstico por imagemRESUMO
Brazil is the second nation in absolute number of new cases of leprosy in the world. The country presents many regions highly endemic to the disease, as is the case of the Goiás. The present study aims to analyze the temporal trends of leprosy indicators in Goiás between 2006 and 2015. This study showed a significant trend of decline for the coefficient of detection. Although the central-western region of the state presented the highest absolute number of cases, the Northeast of the state presents the worst epidemiological situation, with an increase in the number of cases of patients with physical disabilities and those under 14 years of age. The data also showed that there is an increase in the cases of patients with physical deformities in almost all macroregions of the state, indicative of late diagnosis. It is very important that there is a more effective and continuous training of the health professionals of the non-centralized units, for a real control of leprosy as a public health problem in the state. In addition, special attention should be given to the poorer regions of the state, which have shown a tendency to increase the diagnosis of patients younger than 14 years and with physical disabilities caused by leprosy.
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Pessoas com Deficiência , Hanseníase , Brasil/epidemiologia , Diagnóstico Tardio , Doenças Endêmicas , Humanos , Hanseníase/diagnóstico , Hanseníase/epidemiologiaRESUMO
Driving while sleepy on a regular basis may be due to sleep restriction associated with work schedules or with poor sleep hygiene. It also may be associated with sleep disorders or with sedative drugs. This review assesses the potential consequences of driving sleepy on a regular basis from a societal point of view. Driving while sleepy on a regular basis increases the risk of motor vehicle accidents (MVAs), impairs the ability to work, has an impact on productivity, and probably also has an impact on the risk of non-MVA occupational accidents and on public disasters.
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Acidentes de Trânsito/economia , Condução de Veículo , Efeitos Psicossociais da Doença , Sono/fisiologia , Sonolência , Humanos , Distúrbios do Início e da Manutenção do Sono/economia , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Vigília/fisiologiaRESUMO
ABSTRACT Despite being subject to lower AIDS-related mortality rates and having a higher life expectancy, patients with HIV are more prone to develop non-AIDS events. A low CD4+/CD8+ ratio during antiretroviral therapy identifies people with heightened immune senescence and increased risk of mortality. In clinical practice, finding determinants of a low CD4+/CD8+ ratio may be useful for identifying patients who require close monitoring due to an increased risk of comorbidities and death. We performed a prospective study on the evolution of the CD4+/CD8+ ratio in 60 patients infected with HIV (80% males), who were subjected to two different antiretroviral regimens: early and deferred therapy. The initial CD4+/CD8+ ratio was ≤1 for 70% of the patients in both groups. Older age, CD4+ cell count at inclusion, Nadir CD8+T-cell count, and Initial CD4+/CD8+ ratio ≤ 1 were risk factors for lack of ratio recovery. In the multivariate analysis, a CD4+/CD8+ ratio > 1 at the start of the treatment was found to be a determinant factor in maintaining a CD4+/CD8+ ratio > 1. The nadir CD4+T-cell count was lower in the deferred therapy group (p=0.004), and the last CD4+/CD8+ ratio ≤1 was not associated with comorbidities. Ratio recovery was not associated with the duration of HIV infection, time without therapy, or absence of AIDS incidence. A greater improvement was observed in patients treated early (p=0.003). In contrast, the slope of increase was slower in patients who deferred treatment. In conclusion, the increase in the CD4+/CD8+ ratio occurred mostly for patients undergoing early strategy treatment and its extension did not seem to be related to previous HIV-related factors.
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Objetivo: Este estudo teve como objetivo comparar a qualidade da obturação e a resistência de união de dois cimentos endodônticos, AH Plus e Bio-C Sealer, em dentes humanos e bovinos. Métodos: Os canais radiculares de 60 dentes unirradiculares [30 humanos (H) e 30 bovinos (B)] foram preparados e obturados por condensação lateral da guta-percha e AH Plus (grupos AP-H e AP-B) ou Bio-C Sealer (grupos BC-H e BC-B). Seis fatias de 1,5 mm de espessura foram obtidas de cada raiz. Os espécimes foram observados em estereomicroscópio para avaliar a qualidade da obturação, considerando possíveis espaços vazios no material obturador. Posteriormente, as fatias radiculares foram avaliadas em termos de resistência de união por push-out e modo de falha. Os dados foram analisados pelos testes de Mann-Whitney e coeficientes de correlação de Spearman (α=5%). Resultados: A qualidade de obturação fornecida por AP e BC foi semelhante em ambos os substratos de dentina. No entanto, ao comparar dentes humanos e bovinos, os escores de espaços vazios foram maiores nas amostras bovinas, para ambos os cimentos. AP teve maior resistência de união à dentina humana e bovina do que BC. No entanto, não houve diferença significativa na resistência de união entre os substratos dentinários, para ambos os cimentos testados. Além disso, houve uma correlação positiva e moderada entre os valores de resistência de união de dentes humanos e bovinos. O modo de falha misto foi o mais prevalente. Conclusão: AP e BC fornecem qualidade de obturação semelhante, mas o primeiro apresenta maiores valores de resistência de união à dentina humana e bovina. A utilização de dentes bovinos como substitutos de amostras humanas parece ser adequada em estudos relacionados à resistência de união, mas não naqueles que testam a qualidade da obturação endodôntica.(AU)
Objective: This study aimed to compare the filling quality and bond strength of two endodontic sealers, AH Plus and Bio-C Sealer, in human and bovine teeth. Methods: The root canals of 60 [30 human (H) and 30 bovine (B)] single-rooted teeth were prepared and filled by lateral condensation of gutta-percha and AH Plus (groups AP-H and AP-B) or Bio-C Sealer (groups BC-H and BC-B). Six 1.5-mm-thick slices were obtained from each root. The specimens were observed under a stereomicroscope to assess filling quality, considering possible voids within the filling material. Subsequently, root slices were evaluated in terms of push-out bond strength and failure mode. Data were analyzed by Mann-Whitney tests and Spearman correlation coefficients (α=5%). Results: The filling quality provided by AP and BC was similar in both dentin substrates. However, when comparing human and bovine teeth, void scores were greater in the bovine samples, for both sealers. AP had higher bond strength to human and bovine dentin than BC. However, there was no significant difference in bond strength between dentin substrates, for both sealers tested. Also, there was a positive and moderate correlation between the bond strength values of human and bovine teeth. The mixed failure mode was the most prevalent. Conclusion: AP and BC provide similar filling quality, but the first presents higher bond strength values to human and bovine dentin. The use of bovine teeth as substitutes for human samples seems adequate in studies related to bond strength, but not in those testing root canal filling quality.(AU)
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Humanos , Animais , Bovinos , Materiais Restauradores do Canal Radicular/química , Obturação do Canal Radicular/métodos , Silicatos/química , Compostos de Cálcio/química , Resinas Epóxi/química , Valores de Referência , Propriedades de Superfície , Teste de Materiais , Cimentação/métodos , Estatísticas não Paramétricas , Falha de Restauração Dentária , Guta-Percha/químicaRESUMO
Abstract Brazil is the second nation in absolute number of new cases of leprosy in the world. The country presents many regions highly endemic to the disease, as is the case of the Goiás. The present study aims to analyze the temporal trends of leprosy indicators in Goiás between 2006 and 2015. This study showed a significant trend of decline for the coefficient of detection. Although the central-western region of the state presented the highest absolute number of cases, the Northeast of the state presents the worst epidemiological situation, with an increase in the number of cases of patients with physical disabilities and those under 14 years of age. The data also showed that there is an increase in the cases of patients with physical deformities in almost all macroregions of the state, indicative of late diagnosis. It is very important that there is a more effective and continuous training of the health professionals of the non-centralized units, for a real control of leprosy as a public health problem in the state. In addition, special attention should be given to the poorer regions of the state, which have shown a tendency to increase the diagnosis of patients younger than 14 years and with physical disabilities caused by leprosy.
Resumo O Brasil é a segunda nação em número absoluto de novos casos de hanseníase no mundo. O país apresenta muitas regiões altamente endêmicas para a doença, como é caso do estado de Goiás. O presente estudo tem como objetivo analisar as tendências temporais dos indicadores de hanseníase em Goiás, entre 2006 e 2015. Este estudo demonstrou uma tendência significativa de declínio para o coeficiente de detecção. Embora a macrorregião do Centro-Oeste do estado tenha apresentado a maior ocorrência absoluta de casos, o Nordeste do estado apresenta a pior situação epidemiológica, com aumento no número de casos de pacientes com incapacidades físicas e menores de 14 anos. Os dados mostraram, ainda, que há um aumento nos casos de pacientes com deformidades físicas em quase todas as macrorregiões do estado, indicativo de diagnóstico tardio. É muito importante que haja uma formação mais efetiva e contínua dos profissionais de saúde das unidades não centralizadas, para um controle real da hanseníase como problema de saúde pública no estado. Além disso, uma atenção especial deve ser dada às regiões mais pobres do estado, que apresentaram uma tendência de aumento no diagnóstico de pacientes menores de 14 anos e com incapacidades físicas causadas pela hanseníase.
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Humanos , Doenças Endêmicas , Hanseníase/epidemiologia , Brasil/epidemiologia , Diagnóstico Tardio , Hanseníase/diagnósticoRESUMO
ABSTRACT The human leukocyte antigen-G (HLA-G) is a non-classical molecule of the major histocompatibility complex. HLA-G has been associated with the process of tumorigenesis and tumor escape. In this study, we aim to evaluate the HLA-G expression in melanocytic lesions and in melanoma for determining when melanocytic lesions start its expression. Twenty-two skin biopsies samples were submitted to immunohistochemistry; HLA-G expression was detected in 63.6% of the samples. This expression in melanocytic cells was significantly higher in melanoma than in benign melanocytic lesions (p < 0.002). Our results suggest that HLA-G expression starts late in the process of tumorigenesis.
RESUMEN El antígeno leucocitario humano G (HLA-G) es una molécula no clásica del complejo principal de histocompatibilidad que ha sido asociada al proceso de tumorigénesis y escape tumoral. En este estudio, nuestro objetivo es evaluar la expresión de HLA-G en lesiones melanocíticas y en el melanoma para determinar cuando las lesiones melanocíticas comienzan su expresión. Veintidós muestras de biopsias de piel se estudiaron mediante inmunohistoquímica; se detectó la expresión de HLA-G en el 63,6% de las muestras. Esa expresión en las células melanocíticas fue significativamente mayor en el melanoma que en lesiones melanocíticas benignas (p < 0,002). Nuestros resultados sugieren que la expresión de HLA-G empieza tardíamente en el proceso de tumorigénesis.
RESUMO O antígeno leucocitário humano G (HLA-G) é uma molécula não clássica do complexo principal de histocompatibilidade que tem sido associada ao processo de tumorigênese e escape tumoral. Neste estudo, objetivamos avaliar a expressão de HLA-G em lesões melanocíticas e no melanoma para determinar quando as lesões melanocíticas iniciam sua expressão. Vinte e duas amostras de biópsias de pele foram submetidas à imuno-histoquímica; a expressão de HLA-G foi observada em 63,6% das amostras. Essa expressão nas células melanocíticas foi significativamente maior no melanoma do que em lesões melanocíticas benignas (p < 0,002). Nossos resultados sugerem que a expressão de HLA-G se inicia tardiamente no processo da tumorigênese.