Correction: Beyond words: From jaguar population trends to conservation and public policy in Mexico.

[This corrects the article DOI: 10.1371/journal.pone.0255555.].

Retrospective Analysis of Severe Dengue by Dengue Virus Serotypes in a Population with Social Security, Mexico 2023.

BACKGROUND: Risk factors for severe dengue manifestations have been attributed to various factors, including specific serotypes, sex, and age. Mexico has seen the re-emergence of DENV-3, which has not circulated in a decade. OBJECTIVE: To describe dengue serotypes by age, sex, and their association with disease severity in dengue-positive serum samples from epidemiological surveillance system units. MATERIALS AND METHODS: A descriptive analysis was conducted to evaluate the frequency of dengue severity by sex, age, disease quarter, geographical location, and dengue virus serotypes. The study was conducted using laboratory samples from confirmed dengue cases through RT-qPCR from the epidemiological surveillance laboratory network of the Mexican Social Security Institute, Mexico. Simple frequencies and proportions were calculated using the z-test for proportional differences between groups. Bivariate analysis with adjusted Chi2 was performed, and binary logistic regression models were constructed using the forward Wald method considering the model's predictive capacity. The measure of association was the odds ratio, with 95% confidence intervals. Statistical significance was set to an alpha level of <0.05. RESULTS: In 2023, 10,441 samples were processed for dengue RT-qPCR at the IMSS, with a predominance of serotype DENV-3 (64.4%). The samples were mostly from women (52.0%) and outpatient cases (63.3%). The distribution of dengue severity showed significant variations by age, with a lower proportion of severe cases in young children and a higher proportion in the 5- to 14-year-old group. Hospitalizations increased significantly with severity. Warm regions had more cases overall and severity. Cases were most frequent from July to September. While DENV-2 was associated with severity, DENV-4 was not. Binary regression identified higher risk in women, age extremes, and DENV-2, with an overall predictive model of 58.5%. CONCLUSIONS: Women, age groups at the extremes of life, and the DENV-2 serotype presented severe risk of dengue in a population with social security in Mexico during 2023.

Practical Guide to VI-RADS: MRI Protocols, Lesion Characterization, and Pitfalls.

Urothelial carcinoma is the most common type of bladder cancer (BC), accounting for approximately 90% of all cases. Evaluating the depth of tumor invasion in the bladder wall (tumor staging) is essential for determining the treatment and prognosis in patients with BC. Neoadjuvant therapy followed by radical cystectomy is the most common treatment of localized muscle-invasive BC (MIBC). Therefore, it is vital to differentiate non-MIBC from MIBC. Transurethral resection of bladder tumor (TURBT) is the reference standard to determine the extent of tumor invasion into the bladder wall through tissue sampling. However, this diagnostic and therapeutic method may not adequately sample the muscularis propria, leading to a higher risk of residual disease, early recurrence, and tumor understaging in approximately 50% of patients during the initial TURBT. Multiparametric MRI can overcome some of the limitations of TURBT when evaluating BC, particularly regarding tumor staging. In this context, the Vesical Imaging Reporting and Data System (VI-RADS) classification was developed to establish standards for bladder multiparametric MRI and interpretation. It uses a 5-point scale to assess the likelihood of detrusor muscle invasion. T2-weighted MR images are particularly useful as an initial guide, especially for categories 1-3, while the presence of muscular invasion is determined with diffusion-weighted and dynamic contrast-enhanced sequences. Diffusion-weighted imaging takes precedence as the dominant method when optimal image quality is achieved. The presence of a stalk or a thickened inner layer and no evidence of interruption of the signal intensity of the muscular layer are central for predicting a low likelihood of muscle invasion. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material. See the invited commentary by Hoegger in this issue.

Atroposelective Synthesis of Axially Chiral Naphthylpyrroles by a Catalytic Asymmetric 1,3-Dipolar Cycloaddition/Aromatization Sequence.

A straightforward methodology for the enantioselective preparation of axially chiral 2-naphthylpyrroles has been developed. This protocol is based on a CuI/Fesulphos-catalyzed highly enantioselective 1,3-dipolar cycloaddition of an azomethine ylide followed by pyrrolidine alkylation and pyrrolidine to pyrrole oxidation. The mild conditions employed in the DDQ/blue light-mediated aromatization process facilitate an effective central-to-axial chirality transfer affording the corresponding pyrroles with high atroposelectivity.

Saliva sampling and its direct lysis is an excellent option for SARS-CoV-2 diagnosis in paediatric patients: comparison with the PanBio COVID-19 antigen rapid test in symptomatic and asymptomatic children.

Introduction. Lateral flow test (LFTs) have been used as an alternative to reverse transcription quantitative PCR (RT-qPCR) in point-of-care testing. Despite their benefits, the sensitivity of LFTs may be low and is affected by several factors. We have previously reported the feasibility of using direct lysis of individual or pools of saliva samples from symptomatic and asymptomatic patients as a source of viral genomes for detection by RT-qPCR.Hypothesis. Direct lysed saliva is more sensitive than antigen tests to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in samples from children.Aim. Our goals here were to valuate the specificity and sensitivity of the PanBio COVID-19 antigen rapid test device (Ag-RTD) compared with RT-qPCR of direct lysed saliva.Methodology. We evaluated the performance of the PanBio COVID-19 Ag-RTD in comparison to RT-qPCR direct lysed saliva from paired samples of 256 symptomatic and 242 asymptomatic paediatric patients.Results. Overall, although there were no differences in the specificity (96.6%), we found a lower sensitivity (64.3%) of the PanBio Ag-test RTD compared to saliva in both symptomatic and asymptomatic patients. In addition, the sensitivity of PanBio was not correlated with the viral load present in the samples.Conclusion. Our data highlight the benefits of using RT-qPCR and saliva samples for SARS-CoV-2 detection, particularly in paediatric patients.

Homicide among young people in the countries of the Americas.

Objective: To examine the homicide trends among young people (10-24 years), adolescents (10-19 years), and young adults (20-24 years) in 33 countries in the Americas between 2000 and 2019, with a focus on inequalities between countries in the burden of homicides. Methods: An ecological study was performed using estimated deaths from 33 countries. Age-adjusted rates, percentage change (PC), average annual percentage change (AAPC), and relative risk (RR) were estimated; besides, analysis on social inequalities was performed. Results: In the Americas between 2000 and 2019, homicide has been the leading cause of death with 54 515 deaths on average each year and an age-adjusted rate of 23.6 per 100 000 among young people. The highest rate was found in the Andean subregion (41.1 per 100 000 young people), which also produced the highest decrease (PC = -37.1% and AAPC = -2.4%) in the study period. The risk of homicide in young men is 8.1 times the risk in young women, and the risk in young adults is 2.5 times the risk in adolescents. The three countries with highest risk of homicide for young people are Venezuela (relative risk [RR] = 35.1), El Salvador (RR = 28.1), and Colombia (RR = 26.7). The estimated excess mortality was 26.8 homicides per 100 000 in the poorest 20% of countries compared to the richest 20% of countries in the period 2000-2009, and it decreased to 13.9 in the period 2010-2019. Conclusions: The results of this study add to the knowledge of homicide among young people and can be used to inform policy and programming in countries. Given the great burden of homicide on young people in the region, it is critical that prevention opportunities are maximized, beginning early in life.

Patterns of the radiation properties for Peano antennas.

This paper studies metallic microstrip antennas with air as a substrate in the UHF band, patterned after space-filling, self-avoiding, and self-similar (FASS) Peano curves. Our novel study is based on context-free grammar and genetic programming as computing tools to unravel the role of geometry on both; the Voltage Standing Wave Ratio (VSWR[Formula: see text]) and frequency resonance patterns for Peano antennas. We use in our approach the numeric method of moments (MoM) implemented in Matlab 2021a to solve the corresponding Maxwell equations. Novel equations for the patterns of both features (resonance frequencies and frequencies such that the VSWR[Formula: see text]) are provided as functions of the characteristic length L. Antennas spanning a [Formula: see text] area ([Formula: see text]), feeding points set at seven places, and three widths of the metallic strip are introduced as instances of our approach. Finally, a Python 3.7 application is constructed to facilitate the extension and use of our results.

X-ray dose profiles using artificial neural networks.

This paper introduces a novel computational method to simulate and predict radiation dose profiles in a water phantom irradiated by X-rays of 6 and 15 MV at different depths and field sizes using Artificial Neural Networks within the error margin required by the code of practice 398 of the International Atomic Energy Agency (IAEA). Our method uses deep-learning Artificial Neural Networks as an alternative to the Monte Carlo methods usually used nowadays. It reproduces the radiation dose profiles for X-rays of 6 and 15 MV data reported in the British Journal of Radiology (Aird, 1996). Even more, our method reproduces data from other sources with acceptable errors. These simulations pave the way to enhance radiotherapy techniques in planning patient doses and calibrating ionizing radiation measurement instruments used in the fight against cancer.

Homicide among young people in the countries of the Americas / El homicidio entre la población joven de los países de las Américas / Homicídio entre jovens nos países das Américas

ABSTRACT Objective. To examine the homicide trends among young people (10-24 years), adolescents (10-19 years), and young adults (20-24 years) in 33 countries in the Americas between 2000 and 2019, with a focus on inequalities between countries in the burden of homicides. Methods. An ecological study was performed using estimated deaths from 33 countries. Age-adjusted rates, percentage change (PC), average annual percentage change (AAPC), and relative risk (RR) were estimated; besides, analysis on social inequalities was performed. Results. In the Americas between 2000 and 2019, homicide has been the leading cause of death with 54 515 deaths on average each year and an age-adjusted rate of 23.6 per 100 000 among young people. The highest rate was found in the Andean subregion (41.1 per 100 000 young people), which also produced the highest decrease (PC = -37.1% and AAPC = -2.4%) in the study period. The risk of homicide in young men is 8.1 times the risk in young women, and the risk in young adults is 2.5 times the risk in adolescents. The three countries with highest risk of homicide for young people are Venezuela (relative risk [RR] = 35.1), El Salvador (RR = 28.1), and Colombia (RR = 26.7). The estimated excess mortality was 26.8 homicides per 100 000 in the poorest 20% of countries compared to the richest 20% of countries in the period 2000-2009, and it decreased to 13.9 in the period 2010-2019. Conclusions. The results of this study add to the knowledge of homicide among young people and can be used to inform policy and programming in countries. Given the great burden of homicide on young people in the region, it is critical that prevention opportunities are maximized, beginning early in life.

RESUMEN Objetivo. Examinar las tendencias de los homicidios entre la población joven (10-24 años), los adolescentes (10-19 años) y los adultos jóvenes (20-24 años) en 33 países de las Américas entre el 2000 y el 2019, con particular atención a las desigualdades entre los países en materia de cifras de homicidios. Métodos. Se realizó un estudio ecológico utilizando las muertes estimadas de 33 países. Se estimaron las tasas ajustadas en función de la edad, el cambio porcentual (CP), el cambio porcentual anual promedio (CPAP) y el riesgo relativo (RR). Además, se realizó un análisis sobre las desigualdades sociales. Resultados. Entre el 2000 y el 2019, el homicidio ha sido la principal causa de muerte en las Américas, con un promedio anual de 54 515 muertes y una tasa ajustada en función de la edad de 23,6 por cada 100 000 habitantes en la población joven. La tasa más alta se observó en la subregión andina (41,1 por cada 100 000 habitantes para la población joven), en la cual también se observó la mayor disminución (CP = -37,1% y CPAP = -2,4%) en el período de estudio. El riesgo de homicidio entre los hombres jóvenes es 8,1 veces mayor que entre las mujeres jóvenes, y el riesgo entre los adultos jóvenes es 2,5 veces mayor que el riesgo en adolescentes. Los tres países con mayor riesgo de homicidio para los jóvenes son Venezuela (riesgo relativo [RR] = 35,1), El Salvador (RR = 28,1) y Colombia (RR = 26,7). El exceso de mortalidad estimado fue de 26,8 homicidios por cada 100 000 habitantes en el 20% de los países más pobres, en comparación con el 20% de los países más ricos, durante el período 2000-2009, y disminuyó a 13,9 durante el período 2010-2019. Conclusiones. Los resultados de este estudio se suman a los conocimientos sobre el homicidio entre la población joven, y pueden utilizarse para fundamentar las políticas y los programas de los países. Dada la enorme carga de homicidios que sufre la población joven de la región, es fundamental impulsar al máximo las oportunidades de prevención desde las primeras etapas de la vida.

RESUMO Objetivo. Examinar as tendências de homicídios entre pessoas jovens (10 a 24 anos), adolescentes (10 a 19 anos) e adultas jovens (20 a 24 anos) em 33 países das Américas entre 2000 e 2019, com foco em desigualdades da carga de homicídios entre países. Métodos. Foi realizado um estudo ecológico usando estimativas de óbitos de 33 países. Foram estimadas taxas ajustadas por idade, variação percentual (VP), variação percentual anual média (VPAM) e risco relativo (RR); além disso, foi realizada uma análise das desigualdades sociais. Resultados. Entre 2000 e 2019, o homicídio foi a principal causa de morte nas Américas, com uma média de 54.515 óbitos por ano e uma taxa ajustada por idade de 23,6 por 100 mil pessoas entre pessoas jovens. A taxa mais alta foi encontrada na sub-região andina (41,1 por 100 mil jovens), que também registrou a redução mais acentuada (VP = -37,1% e VPAM = -2,4%) no período do estudo. O risco de homicídio entre homens jovens é 8,1 vezes maior que o risco em mulheres jovens, e o risco entre pessoas adultas jovens é 2,5 vezes maior que o risco em adolescentes. Os três países com maior risco de homicídio entre pessoas jovens são Venezuela (RR = 35,1), El Salvador (RR = 28,1) e Colômbia (RR = 26,7). Nos países, o excesso de mortalidade estimado foi de 26,8 homicídios por 100 mil habitantes nos 20% mais pobres comparados aos 20% mais ricos no período de 2000 a 2009. Esse número diminuiu para 13,9 no período de 2010 a 2019. Conclusões. Os resultados deste estudo se somam às informações sobre homicídios entre jovens e podem ser usados para embasar políticas e programas nacionais. Dado o grande ônus que os homicídios representam para as pessoas jovens da região, é fundamental que as oportunidades de prevenção sejam maximizadas desde cedo em suas vidas.

Pooling saliva samples as an excellent option to increase the surveillance for SARS-CoV-2 when re-opening community settings.

In many countries a second wave of infections caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has occurred, triggering a shortage of reagents needed for diagnosis and compromising the capacity of laboratory testing. There is an urgent need to develop methods to accelerate the diagnostic procedures. Pooling samples represents a strategy to overcome the shortage of reagents, since several samples can be tested using one reaction, significantly increasing the number and speed with which tests can be carried out. We have reported the feasibility to use a direct lysis procedure of saliva as source for RNA to SARS-CoV-2 genome detection by reverse transcription quantitative-PCR (RT-qPCR). Here, we show that the direct lysis of saliva pools, of either five or ten samples, does not compromise the detection of viral RNA. In addition, it is a sensitive, fast, and inexpensive method that can be used for massive screening, especially considering the proximity of the reincorporation of activities in universities, offices, and schools.

Beyond words: From jaguar population trends to conservation and public policy in Mexico.

The jaguar (Panthera onca) is one of the most threatened carnivores in the Americas. Despite a long history of research on this charismatic species, to date there have been few systematic efforts to assess its population size and status in most countries across its distribution range. We present here the results of the two National Jaguar Surveys for Mexico, the first national censuses in any country within the species distribution. We estimated jaguar densities from field data collected at 13 localities in 2008-2010 (2010 hereafter) and 11 localities in 2016-2018 (2018 hereafter). We used the 2010 census results as the basis to develop a National Jaguar Conservation Strategy that identified critical issues for jaguar conservation in Mexico. We worked with the Mexican government to implement the conservation strategy and then evaluated its effectivity. To compare the 2010 and 2018 results, we estimated the amount of jaguar-suitable habitat in the entire country based on an ecological niche model for both periods. Suitable jaguar habitat covered ~267,063 km2 (13.9% of the country's territory) in 2010 and ~ 288,890 km2 (~14.8% of the country's territory) in 2018. Using the most conservative density values for each priority region, we estimated jaguar densities for both the high and low suitable habitats. The total jaguar population was estimated in ~4,000 individuals for 2010 census and ~4,800 for the 2018 census. The Yucatan Peninsula was the region with the largest population, around 2000 jaguars, in both censuses. Our promising results indicate that the actions we proposed in the National Jaguar Conservation Strategy, some of which have been implemented working together with the Federal Government, other NGO's, and land owners, are improving jaguar conservation in Mexico. The continuation of surveys and monitoring programs of the jaguar populations in Mexico will provide accurate information to design and implement effective, science-based conservation measures to try to ensure that robust jaguar populations remain a permanent fixture of Mexico's natural heritage.

Saliva Sampling and Its Direct Lysis, an Excellent Option To Increase the Number of SARS-CoV-2 Diagnostic Tests in Settings with Supply Shortages.

As part of any plan to lift or ease the confinement restrictions that are in place in many different countries, there is an urgent need to increase the capacity of laboratory testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Detection of the viral genome through reverse transcription-quantitative PCR (RT-qPCR) is the gold standard for this virus; however, the high demand of the materials and reagents needed to sample individuals, purify the viral RNA, and perform the RT-qPCR has resulted in a worldwide shortage of several of these supplies. Here, we show that directly lysed saliva samples can serve as a suitable source for viral RNA detection that is less expensive and can be as efficient as the classical protocol, which involves column purification of the viral RNA. In addition, it bypasses the need for swab sampling, decreases the risk of the health care personnel involved in the testing process, and accelerates the diagnostic procedure.

Prostate imaging reporting and data system correlation with Gleason score: Pathological aspects of magnetic resonance imaging findings.

OBJECTIVE: Prostate cancer has a high prevalence and mortality, being the most diagnosed urologic cancer. Prostatic magnetic resonance imaging showed high sensitivity in the detection of clinically significant neoplasia and agreement with the Gleason score. Therefore, we attempted to evaluate the diagnostic accuracy of the prostate imaging reporting and data system, using biopsy and prostatectomy as the reference standard. The secondary goal of correlating prostatic magnetic resonance imaging findings and anatomopathological samples is obtained. MATERIALS AND METHODS: We retrospectively analyzed seventy-nine 1.5 Tesla prostatic magnetic resonance imaging scans in patients aged 31 to 86 years, performed at the Clinical Hospital of the Federal University of Paraná between January 2015 and February 2018. RESULTS: Considering all 79 patients, prostatic magnetic resonance imaging was able to diagnose tumor in 47 patients (59.4%). Considering the peripheral zone, the prostatic magnetic resonance imaging had a sensitivity of 75.0% (95% confidence interval: 52.1%-98.0%), specificity of 89.5% (95% confidence interval: 66.0%-100%), 94.4% positive predictive value (95% confidence interval: 71.0%-100%), 66.7% negative predictive value (95% confidence interval: 43.0%-69.0%), 83.8% Positive Likelihood Ratio (PVR) (95% confidence interval: 60.0%-100%), 27.9% Negative Likelihood Ratio (RVN) (95% confidence interval: 5.0%-50.0 %), and accuracy of 86.3% (95% confidence interval: 63.0%-100%). The receiver operating characteristic curve obtained demonstrated the sensitivity variation according to the prostate imaging reporting and data system score of the patients, obtaining an area under the curve of 84.8 for a prostate imaging reporting and data system cutoff of 3. CONCLUSION: The use of the prostate imaging reporting and data system score is useful for the screening and classification of prostate cancer, due to its easy reproducibility, even in a population with an unknown prostate cancer prevalence, which can be easily correlated with biopsy studies and/or radical prostatectomy.

Computational model of gamma irradiation room at ININ.

In this paper, we present a model of the gamma irradiation room at the National Institute of Nuclear Research (ININ is its acronym in Spanish) in Mexico to improve the use of physics in dosimetry for human protection. We deal with air-filled ionization chambers and scientific computing made in house and framed in both the GEANT4 scheme and our analytical approach to characterize the irradiation room. This room is the only secondary dosimetry facility in Mexico. Our aim is to optimize its experimental designs, facilities, and industrial applications of physical radiation. The computational results provided by our model are supported by all the known experimental data regarding the performance of the ININ gamma irradiation room and allow us to predict the values of the main variables related to this fully enclosed space to within an acceptable margin of error.

Reverse Distal Transverse Palmar Arch in Distal Digital Replantation.

BACKGROUND: Refinements in microsurgery have made distal finger replantation an established technique with high success rates and good functional and aesthetic outcomes. However, it still represents a technically demanding procedure due to the small vessel caliber and frequent lack of vessel length, requiring the use of interpositional venous grafts in some instances. We describe a new technique for anastomosis in fingertip replantation, whereby the need for venous grafts is eliminated. METHODS: Applying the reverse distal transverse palmar arch technique, 11 cases of distal digital replantation were performed between January 2011 and July 2016. The described procedure was used for arterial anastomosis in 10 cases and arteriovenous shunting for venous drainage in 1 case. A retrospective case review was conducted. The technical description and clinical outcome evaluations are presented. RESULTS: Ten of the 11 replanted digits survived, corresponding to an overall success rate of 91%. One replant failed due to venous insufficiency. Blood transfusions were not required for any of the patients. Follow-up (range, 1.5-5 months) revealed near-normal range of motion and good aesthetic results. All of the replanted digits developed protective sensation. The average length of hospital admission was 5 days. All patients were satisfied with the results and were able to return to their previous work. CONCLUSIONS: The use of the reverse distal transverse palmar arch is a novel and reliable technique in distal digital replantation when an increase in vessel length is required, allowing for a tension-free arterial repair without the need for vein grafts.

Prevalence of pneumococcal disease, serotype distribution, and antimicrobial susceptibility in Mexican children younger than 5 years of age.

BACKGROUND AND AIMS: Streptococcus pneumoniae constitutes one of the main causes of sepsis, bacteremia and meningitis (pneumococcal invasive disease - PID), and pneumonia in infants and small children. Antipneumococcal vaccination in Mexico is expected to be a useful strategy to reduce morbimortality due to this cause. We undertook this study to determine the prevalence of PID and pneumonia and the PCV vaccination status of affected children as well as serotype distribution and antimicrobial susceptibility of pneumococcal strains responsible for PID in infants and small children in Mexico. METHODS: From March 2010-June 2011, a prospective multicenter study was carried out in four states in Mexico to determine the prevalence of bacteremia, meningitis, septic arthritis and pneumonia due to S. pneumoniae and other microorganisms in children from 28 days-59 months of age. Isolated pneumococcal strains were serotyped and their antimicrobial resistance determined. RESULTS: During the study period, 545 children were diagnosed with bacteremia, meningitis, septic arthritis or pneumonia; 46.7% of these clinical entities occurred among children <12 months of age. Community-acquired pneumonia was the most prevalent disease. It was possible to identify a causal microorganism in 55 cases, from which 80% were S. pneumoniae. Fifteen percent of patients with PID died. The most prevalent pneumococcal serotypes were 19A, 35B, 19F and 6A. 10.2% of nonmeningeal strains were resistant to meropenem and 82% were resistant to TMP/SMX. CONCLUSIONS: This study shows that pneumococcus was the most common bacteria isolated in the studied population, although epidemiological and laboratory-based surveillance still needs improvement.

[Epstein-Barr virus presence in Colombian Hodgkin lymphoma cases and its relation to treatment response]. / Presencia del virus de Epstein-Barr en casos colombianos de linfoma de Hodgkin y su relación con la respuesta al tratamiento.

The role of Epstein-Barr virus as etiologic agent in Hodgkin lymphoma (HL) development has been supported by the detection of viral DNA in the Reed-Sternberg cell in a subset of HL, and the high levels of latent membrane protein 1 expression in these tumors. To gain further evidence of this relationship, lymph nodes from 67 patients with HL were analyzed for the presence of Epstein-Barr virus using EBERs in situ hybridization and LMP-1 immunohistochemistry. Virus presence was related to histological subtype, patients' treatment response and tumor infiltrating lymphocytes phenotype. EBERs transcripts were found in 67% of the cases and LMP-1 in the Reed-Sternberg tumor cells at a 56.7% rate. The prevalence, as determined by histological subtype, was 69.81% for nodular sclerosing, 85.71% for mixed cellularity and 40% for lymphocyte-rich. Epstein-Barr virus presence was more frequent in children (84.2%) in comparison with adults (60.4%). Positive patients presented higher failure-free survival rates than Epstein-Barr virus negative patients. CD4 positive infiltrating T cells were present in a higher proportion in relation to CD8 positive T infiltrating cells, the mean percentages for both subsets were higher in Epstein-Barr virus positive cases. A high percentage of Epstein-Barr virus was present in HL with a probable association with treatment response. This suggests an application of Epstein-Barr virus detection to use as a prognosis marker in treatment response for HL cases.

Presencia del virus de Epstein-Barr en casos colombianos de linfoma de Hodgkin y su relación con la respuesta al tratamiento / Epstein-Barr virus presence in Colombian Hodgkin lymphoma cases and its relation to treatment response

En el desarrollo y patogénesis del linfoma de Hodgkin se ha propuesto al virus de Epstein-Barr como posible factor etiológico debido a la detección de ADN viral en las células de Reed-Sternberg en un subgrupo de tumores y a los altos niveles de expresión de la proteína latente de membrana 1 (LMP-1). El objetivo de este estudio fue determinar la presencia de virus de Epstein-Barr en 67 ganglios linfáticos de pacientes con diagnóstico confirmado de linfoma de Hodgkin mediante hibridación in situ para la detección de transcritos de ARN del virus de Epstein-Barr e inmunohistoquímica para la detección de la proteína oncogénica LMP-1. La presencia del virus se relacionó con el subtipo histológico, la respuesta al tratamiento de los pacientes y el fenotipo del infiltrado linfocitario. En el 67% de los casos se detectaron transcritos de virus de Epstein-Barr, la proteína LMP-1 se detectó en 56,7% de los casos en la célula tumoral de Reed-Sternberg. La presencia del virus en cada tipo histológico fue de 69,81% en esclerosis nodular, 85,71% en celularidad mixta y 40% en clásico. El virus de Epstein-Barr se detectó con mayor frecuencia en niños (84,2%) en comparación con los adultos (60,4%) y los pacientes positivos para el virus mostraron mejor respuesta al tratamiento, reflejada en una menor tendencia a presentar recaídas. El análisis del infiltrado mostró un predominio de linfocitos T CD4 y presencia de linfocitos T CD8, con mayor expresión de ambas subpoblaciones en casos positivos para virus de Epstein-Barr. Los resultados muestran un alto porcentaje de infección por virus de Epstein-Barr con una probable implicación significativa en la respuesta al tratamiento, lo que sugiere que la detección de virus de Epstein-Barr se podría usar como marcador de pronóstico en este tipo de linfoma.

The role of Epstein-Barr virus as etiologic agent in Hodgkin lymphoma (HL) development has been supported by the detection of viral DNA in the Reed-Sternberg cell in a subset of HL, and the high levels of latent membrane protein 1 expression in these tumors. To gain further evidence of this relationship, lymph nodes from 67 patients with HL were analyzed for the presence of Epstein-Barr virus using EBERs in situ hybridization and LMP-1 immunohistochemistry. Virus presence was related to histological subtype, patients´ treatment response and tumor infiltrating lymphocytes phenotype. EBERs transcripts were found in 67% of the cases and LMP-1 in the Reed-Sternberg tumor cells at a 56.7% rate. The prevalence, as determined by histological subtype, was 69.81% for nodular sclerosing, 85.71% for mixed cellularity and 40% for lymphocyte-rich. Epstein-Barr virus presence was more frequent in children (84.2%) in comparison with adults (60.4%). Positive patients presented higher failure-free survival rates than Epstein-Barr virus negative patients. CD4 positive infiltrating T cells were present in a higher proportion in relation to CD8 positive T infiltrating cells, the mean percentages for both subsets were higher in Epstein-Barr virus positive cases. A high percentage of Epstein-Barr virus was present in HL with a probable association with treatment response. This suggests an application of Epstein-Barr virus detection to use as a prognosis marker in treatment response for HL cases.