Corneal transplantation and concomitant SARS-CoV-2 infection: a case report / Transplante de córnea e infecção concomitante por SARS-CoV-2: relato de caso

ABSTRACT This report was aimed at presenting a case of neurotrophic keratitis and concomitant SARS-CoV-2 infection in a patient who has recently undergone a corneal DALK transplant. One month after corneal transplantation with adequate corneal epithelialization, the patient presented neurotrophic keratitis with a torpid course of the corneal transplant coinciding with a SARS-CoV-2 infection, with an excessive host immune response. In addition, the patient presented a re-positivization of nasopharyngeal polymerase chain reaction of SARS-CoV-2 with past disease after starting treatment with autologous serum eye drops. The implications at the ophthalmological level of SARS-CoV-2 infection may be clarified as the time the illness progresses and we learn more about how it acts. In this case, the disparity of signs and symptoms, the antecedent of corneal surgery, and the possibility of a herpetic infection as a cause of the primary leukoma suggested neurotrophic keratitis. Nonetheless, the involvement of systemic SARS-CoV-2 infection in the process, triggering an excessive host immune response at the corneal level with an increase in inflammatory cytokines must be taken into account. No relationship was found between treatment with autologous serum and re-positivization of nasopharyngeal polymerase chain reaction, presenting the patient a favorable response to treatment.

RESUMO O objetivo deste relato foi apresentar um caso de ceratite neurotrófica e infecção concomitante por SARS-CoV-2 em paciente submetido recentemente a transplante de córnea DALK. Um mês após o transplante de córnea com adequada epitelização da córnea, o paciente apresentou ceratite neurotrófica com curso tórpido do transplante de córnea, coincidindo com infecção por SARS-CoV-2, com resposta imune excessiva do hospedeiro. Além disso, o paciente apresentou repositivização da reação em cadeia da polimerase nasofaríngeo de SARS-CoV-2, com doença pregressa após iniciar tratamento com colírio de soro autólogo. As implicações a nível oftalmológico da infecção por SARS-CoV-2, podem ser esclarecidas à medida que a doença progride e aprendemos mais sobre sua forma de atuação. Neste caso, a disparidade de sinais e sintomas, o antecedente de cirurgia de córnea e a possibilidade de infecção herpética como causa do leucoma primário sugeriram ceratite neurotrófica. No entanto, deve-se levar em consideração o envolvimento da infecção sistêmica por SARS-CoV-2 no processo, desencadeando uma resposta imune excessiva do hospedeiro no nível da córnea, com aumento de citocinas inflamatórias. Não foi encontrada relação entre o tratamento com soro autólogo e a repositivização da reação em cadeia da polimerase nasofaríngea, apresentando ao paciente uma resposta favorável ao tratamento.

Medición de los niveles de lactato sérico y frecuencia cardiaca en caninos (Canis lupus familiaris) braquicefálicos, mesocefálicos y dolicocefálicos sometidos a prueba de esfuerzo en trotadora motorizada / Measurement of serum lactate levels and heart rate in canines (Canis lupus familiaris) Brachycephalic, Mesocephalic and Dolichocephalic submitted to a stress test on a motorized treadmill

RESUMEN Se analizaron los niveles de lactato sérico y de frecuencia cardiaca (FC) en 15 perros clinicamente sanos que fueron sometidos a pruebas de esfuerzo en trotadora motorizada, buscando verificar un grado de fatiga muscular frente a una prueba de esfuerzo intenso. Se consideraron pacientes con morfologia craneana de tipo braquicefálico, mesocefálico y dolicocefálico. Las mediciones séricas de lactato fueron conseguidas por medio de un medidor portátil, mientras que las frecuencias cardiacas se obtuvieron a través de un oximetro portátil a los tiempos 0, 10, 20 y 30 minutos, en los diferentes momentos de esfuerzo fisico en la trotadora motorizada, la cual fue adaptada en su inclinación en 15% y a un máximo de velocidad de 10 km/h. Las medias de los niveles séricos entre perros mesocefálicos y dolicocefálicos fueron significativas, a diferencia de los perros braquicefálicos los cuales resultaron no significativos. Las medias de las frecuencias cardiacas no tuvieron diferencia significativa bajo un 95% de confianza.

ABSTRACT Serum lactate and heart rate (HR) levels were analyzed in 15 clinically healthy dogs that were subjected to stress tests on a motorized treadmill, seeking to verify a degree of muscle fatigue compared to an intense exercise test. Patients with brachycephalic, mesocephalic and dolichocephalic type cranial morphology were considered. Serum lactate measurements were procured by means of a portable meter, while heart rates were obtained through a portable oximeter at the times 0, 10, 20, and 30 minutes at different moments of physical effort on the motorized treadmill, which was adapted in its inclination by 15% and at a maximum speed of 10 km/h. Mean serum levels between mesocephalic and dolichocephalic dogs were significant, unlike brachycephalic dogs, which were not significant. The mean heart rates did not have a significant difference under 95% confidence.

Niveles séricos de la isoenzima creatina quinasa-MB y lactato deshidrogenasa como indicadores de daño miocárdico en perros con enfermedad valvular degenerativa / Serum levels of the isoenzyme creatine kinase-MB and lactate dehydrogenase as indicators of myocardial damage in dogs with degenerative valve disease

RESUMEN Se analizaron los niveles séricos de creatina quinasa-MB (CK-MB) y lactato deshidrogenasa (LDH) en 10 perros diagnosticados con enfermedad valvular degenerativa y en seis perros clinicamente sanos, con el objetivo de evaluar si sus niveles séricos indican daño miocárdico. Las muestras de suero se analizaron mediante el método UV. Se utilizó la prueba de diferenciación de medias para determinar diferencias entre medias, y la prueba de correlación de Pearson para determinar si existe correlación entre los niveles séricos de ambas enzimas. Los valores de CK-MB y de LDH fueron significativamente diferentes entre los dos grupos de pacientes. Los niveles de CK-MB y LDH tuvieron correlación positiva, pero no significativa.

ABSTRACT Serum levels of creatine kinase-MB (CK-MB) and lactate dehydrogenase (LDH) were analyzed in 10 dogs diagnosed with degenerative valvular disease and in six clinically healthy dogs with the objective of evaluating whether their serum levels indicate myocardial damage. Serum samples were analyzed by UV method. The mean differentiation test was used to determine differences between means and the Pearson correlation test was performed to determine if there was a correlation between the serum levels of both enzymes. The CK-MB and LDH values were significantly different between the two groups of patients. The levels of CK-MB and LDH had a positive but not significant correlation.

Validación de un método analítico para cuantificación de ferritina en líquido cefalorraquídeo / Validation of an analytical method for the quantification of ferritin in cerebrospinal fluid

Resumen La ferritina es una proteína de gran tamaño que se encuentra fisiológicamente en el líquido cefalorraquídeo (LCR) en concentraciones de 2-10 ng/mL. Su elevación puede utilizarse como biomarcador en distintas condiciones patológicas. El procedimiento de validación tradicional para la medición en LCR no puede ser utilizado debido a la ausencia de controles y calibradores comerciales para esta matriz. El objetivo de este trabajo fue llevar a cabo una validación analítica de ferritina en LCR. Se realizaron ensayos de estimación de precisión y veracidad mediante el protocolo EP15-A3, linealidad por el protocolo EP6-A (ambos de la guía de la CLSI), recuperación, estabilidad, contaminación por arrastre, interferencia por hemólisis y bilirrubina y límite de detección (LoD). La ferritina en LCR en el autoanalizador DxI 800 de Beckman Coulter tuvo una performance intra e interensayo <3,7%, el ensayo denota linealidad en el intervalo de 2,1-547 ng/mL; se estableció estabilidad por un período de 5 días y la recuperación resultó ser aceptable. No se evidenció efecto de contaminación por arrastre ni interferencia por hemólisis hasta un rango entre 300-500 mg/dL de hemoglobina, ni interferencia por bilirrubina hasta una concentración de 16,0 mg/dL de bilirrubina total. El LoD fue de 0,4 ng/mL. Por medio de los ensayos realizados se logró validar la ferritina en LCR a partir de la utilización de pools de muestras, lo que pudo garantizar la confiabilidad y exactitud del método analítico.

Abstract Ferritin is a large protein physiologically present in the cerebrospinal fluid (CSF) in concentrations of 2-10 ng/mL. Its elevation can be used as a biomarker in several pathological conditions. The traditional validation procedure for measurement in CSF cannot be used due to the absence of commercial controls and calibrators for this matrix. The objective of the present study was to perform CSF ferritin analytical validation. Assays such as precision and accuracy estimation through the EP15-A3 protocol, linearity according to the EP6-A protocol (both from the CLSI guidelines), recovery, stability, carry-over, hemolysis and bilirubin interference and limit of detection (LoD) were conducted. Serum samples with different concentrations of ferritin were added to aliquots of a normal CSF pool. CSF ferritin in the Beckman Coulter DxI 800 had a <3.7% intra and inter-assay performance, the assay shows linearity in the 2.1 -547 ng/mL interval, stability was established for a 5-day period and the recovery was acceptable. There was neither carry-over effect or hemolysis interference up to a range of 300-500 mg/dL of hemoglobin, nor interference by bilirubin up to 16.0 mg/dL of total bilirubin. The LoD was 0.4 ng/mL. By means of the performed assays, CSF ferritin was validated by using sample pools, thereby ensuring the reliability and accuracy of the analytical method.

Resumo A ferritina é uma grande proteína fisiologicamente encontrada no líquido cefalorraquidiano (LCR) em concentrações de 2 a 10 ng/mL. Sua elevação pode ser usada como biomarcador em diferentes condições patológicas. O procedimento de validação tradicional para medição no LCR não pode ser usado devido à ausência de controles e calibradores comerciais para esta matriz. O objetivo deste estudo foi realizar uma validação analítica da ferritina no LCR. Foram realizados estudos de precisão e veracidade utilizando o protocolo EP15-A3, linearidade pelo protocolo EP6-A (ambos das diretrizes do CLSI), recuperação, estabilidade, contaminação transportada, interferência de hemólise e bilirrubina e limite de detecção (LoD). A ferritina no LCR no DxI 800 da Beckman Coulter teve um desempenho intra e inter-ensaio <3,7%, o ensaio denota linearidade na faixa de 2,1-547 ng/mL, a estabilidade foi estabelecida em um período de 5 dias e a recuperação foi considerado aceitável. Nenhum efeito de transporte ou interferência por hemólise foi evidenciado até um intervalo entre 300-500 mg/dL de hemoglobina, nem interferência pela bilirrubina até uma concentração de 16,0 mg/dL de bilirrubina total. O LoD foi de 0,4 ng/mL. Através dos testes realizados, a ferritina no LCR foi validada, com base no uso de pool de amostras, o que poderia garantir a confiabilidade e a acurácia do método analítico.

Verificación del desempeño general del método Elecsys® Chagas en la detección de anticuerpos específicos contra Trypanosoma cruzi / Verification of the general performance of the Elecsys® Chagas method in the detection of specific antibodies against Trypanosoma cruzi

Resumen La enfermedad de Chagas es una parasitosis producida por Trypanosoma cruzi, prevalente principalmente en el continente americano, y observada en regiones no endémicas, producto de viajes y migraciones. El objetivo de este estudio fue comparar el desempeño del ensayo Elecsys® Chagas (Roche Diagnostics Alemania) (ECLIA) para el diagnóstico de la infección chagásica crónica con el método estándar y evaluar su posible empleo en reemplazo del método automatizado existente. Se estudiaron 77 muestras de sueros pertenecientes a pacientes con diagnóstico presuntivo de enfermedad de Chagas, procesadas por los distintos métodos disponibles en la Sección Parasitología del Hospital Muñiz: inmunoensayo quimioluminiscente de micropartículas (CMIA) (Abbott), enzimoinmunoanálisis de adsorción (ELISA) (Wiener) y hemaglutinación indirecta (HAI) (Lab. Lemos S.R.L.). Los resultados de los métodos ELISA y HAI fueron comparados con los obtenidos en la prueba ECLIA, y estos a su vez con el método automatizado disponible. De las muestras analizadas, 22 (28,57%) presentaron IgG anti-T. cruzi y 55 (71,43%) resultaron negativas. Con el método ECLIA se logró un 100% en los parámetros de desempeño, con diferencias en los intervalos de confianza. La razón de verosimilitud positiva y la razón de verosimilitud negativa clasificaron al ensayo como excelente y la potencia global del test apoyó esa afirmación. Los métodos inmunológicos automatizados ayudan a la performance diagnóstica en la etapa crónica de la enfermedad de Chagas, permiten minimizar errores, favorecen la velocidad de emisión de los resultados y, debido a su alta sensibilidad y especificidad, en ciertos escenarios podrían proponerse para usar como única técnica.

Abstract Chagas disease is a parasitosis caused by Trypanosoma cruzi, prevalent mainly in the American continent, and observed in non-endemic regions as a result of travel and migration. The objective of this study was to compare the performance of the Elecsys® Chagas (Roche Diagnostics Alemania) (ECLIA) assay for the diagnosis of chronic Chagas infection with the diagnostic standard, and to evaluate its possible use as a replacement for the existing automated method. A total of 77 serum samples belonging to patients with a presumptive diagnosis of Chagas disease were evaluated, processed by the different methods available in the Parasitology Section of Hospital Muñiz: microparticle chemiluminescent immunoassay (CMIA) (Abbott), enzyme-linked immunosorbent assay (ELISA) (Wiener) and indirect hemagglutination (HAI) (Lab. Lemos S.R.L). The results of the ELISA and HAI methods were compared with those obtained in the ECLIA test, and these in turn with the available automated method. Of the samples analysed, 22 (28.57%) presented IgG anti-T. cruzi and 55 (71.43%) were negative. With the ECLIA method, 100% was achieved in the performance parameters, with differences in the confidence intervals. The positive likelihood ratio and the negative likelihood ratio classify the essay as excellent, and the overall power of the test supports this statement. Automated immunological methods help diagnostic performance in the chronic stage of Chagas disease, allow minimising errors, favour the speed of issuance of results, and due to the high sensitivity and specificity, in certain scenarios, they could be proposed for use as single technique.

Resumo A doença de Chagas é uma parasitose causada pelo Trypanosoma cruzi, prevalente principalmente no continente americano, e observada em regiões não endêmicas em decorrência de viagens e migrações. O objetivo deste estudo foi comparar o desempenho do ensaio Elecsys® Chagas (Roche Diagnostics Alemanha) (ECLIA) para o diagnóstico da infecção crônica de Chagas com o método padrão e avaliar seu possível uso em substituição do método automatizado existente. Foram avaliadas 77 amostras de soro pertencentes a pacientes com diagnóstico presuntivo de doença de Chagas, processadas pelos diferentes métodos disponíveis na Seção de Parasitologia do Hospital Muñiz: imunoensaio quimioluminescente de micropartículas (CMIA) (Abbott), ensaio imunoenzimático de adsorção (ELISA) (Wiener) e hemaglutinação indireta (HAI) (Lab. Lemos S.R.L). Os resultados dos métodos ELISA e HAI foram comparados com os obtidos no teste ECLIA, e estes por sua vez com o método automatizado disponível. Das amostras analisadas, 22 (28,57%) apresentaram IgG anti-T. cruzi e 55 (71,43%) foram negativos. Com o método ECLIA, foram obtidos 100% nos parâmetros de desempenho, com diferenças nos intervalos de confiança. A razão de verossimilhança positiva e a razão de verossimilhança negativa classificam o ensaio como excelente, e a potencia geral do teste conformou essa afirmação. Os métodos imunológicos automatizados auxiliam no desempenho diagnóstico na fase crônica da doença de Chagas, permitem minimizar erros, favorecem a rapidez na emissão dos resultados e, devido à alta sensibilidade e especificidade, em determinados cenários, poderiam ser propostos para uso como técnica única.

Aplicación de un método in house para el estudio de la esclerosis múltiple / Application of an in-house method for the study of multiple sclerosis

Resumen El método de referencia para el estudio bioquímico de la esclerosis múltiple (EM) es el isoelectroenfoque (IEE) y la evaluación de las cadenas livianas libres (CLL) podría brindar una información adicional de relevancia. Por lo tanto, se propone evaluar la presencia de las CLL y la aplicabilidad de los estados de polimerización en el estudio de la EM. Se puso a punto un método compuesto por una separación electroforética en gel de poliacrilamida al 12,5% con posterior electrotransferencia (PAGE-WB) y se realizó la evaluación de 121 pacientes con sospecha de EM en simultáneo al IEE. Los patrones de PAGE-WB relacionados con la EM fueron el aumento de la concentración de monómeros Kappa o dímeros Lambda en líquido cefalorraquídeo (LCR) en comparación con el suero. Este método tuvo una muy alta significación de asociación con el IEE (p<0,0001) con sensibilidad del 95%, especificidad del 90%, VPP 83% y VPN 97%. La síntesis intratecal de CLL quedó evidenciada por el aumento de intensidad del monómero Kappa y/o el dímero Lambda observado en LCR. La técnica de PAGE-WB para CLL demostró ser un método alternativo para detectar la síntesis intratecal en pacientes con sospecha de EM.

Abstract The reference method for the biochemical study of multiple sclerosis (MS) is isoelectric focusing (IEF) and the evaluation of free light chains (FLC) could provide additional information of relevance. Therefore, it is proposed here to evaluate the presence of FLC and the applicability of the polymerisation states in the study of MS. A method consisting of a 12.5% polyacrylamide gel electrophoretic separation with a subsequent electrotransfer (PAGE-WB) was developed and the evaluation of 121 patients with suspected MS was carried out simultaneously with the IEF. MS-related PAGE-WB patterns were the increase in the concentration of Kappa monomers or Lambda dimers in CSF compared to serum. This method had a very high significance of association with the IEF (p<0.0001) with 95% sensitivity, 90% specificity, 83% PPV and 97% NPV. Intrathecal synthesis of FLC was evidenced by the increased intensity of the Kappa monomers and/or Lambda dimers observed in CSF. The PAGE-WB technique for FLC proved to be an alternative method to detect intrathecal synthesis in patients with suspected MS.

Resumo O método de referência para o estudo bioquímico da esclerose múltipla (EM) é a focalização isoelétrica (IEE) e a avaliação de cadeias leves livres (CLL) poderiam fornecer informações adicionais de relevância. Assim, propõe-se avaliar a presença das CLL e a aplicabilidade dos estados de polimerização no estudo de EM. Foi desenvolvido um método que consiste na separação eletroforética em gel de poliacrilamida a 12,5% com posterior eletrotranferência (PAGE-WB) e a avaliação de 121 pacientes com suspeita de EM foi realizada paralelamente à IEE. Os padrões de PAGE-WB relacionados com a EM foram o aumento na concentração de monômeros Kappa ou dímeros Lambda em líquido cefalorraquidiano (LCR) em comparação com o soro. Este método teve uma associação de significância muito alta com o IEE (p<0,0001) com sensibilidade de 95%, especificidade de 90%, VPP 83% e VPN 97%. A síntese intratecal de CLL foi evidenciada pelo aumento de intensidade do monômero Kappa e/ou dímero Lambda observado em LCR. A técnica PAGE-WB para CLL mostrou-se um método alternativo para detectar a síntese intratecal em pacientes com suspeita de EM.

Guia rápido de coleta, armazenamento, transporte e entrega de amostras biológicas / Quick collection guide, storage, transport and sample delivery biological

Guia dividido em : Orientações gerais por agravo e Orientações gerais para coleta

Nelore females along a new Brazilian agricultural frontier: hematological and clinical-biochemical approaches / [Abordagens hematológicas e bioquímicas clínicas de fêmeas Nelore na nova fronteira agrícola brasileira]

The Nelore breed is the second largest bovine breed in the world and has actively participated in the expansion of new Brazilian agricultural frontiers. In this context, the purpose of this study was to determine the hematological and biochemical reference intervals of healthy Nelore matrices raised under an extensive regime without supplementation along southwest of Piauí state. Blood samples were collected from fifty-five multiparous female of the Nelore breed. Biochemical and hematological parameters were analyzed using a parametric statistical method with 95% CI of reference limits. The average values of red blood cells, hemoglobin as well as hematimetric indices showed reference ranges similar to reference standards. The hematocrit as well as granulocytes and agranulocytes presented alterations typical of animals raised in environments with higher temperatures. Mineral, enzymatic, protein and metabolic profiles were similar to other bovine breeds but with a narrower range of values. However, lower mean values were observed for levels of ionized calcium, total protein and urea. Nelore females present slightly different biochemical and hematological profiles from other breeds, which might result from the environmental and nutritional management applied and the natural deficiency of nitrogen, phosphorus and calcium in the region's pastures.(AU)

Nelore é a segunda maior raça bovina do mundo e tem participado ativamente da expansão das novas fronteiras agrícolas brasileiras. Nesse contexto, o objetivo do presente estudo foi determinar os intervalos de referência hematológicos e bioquímicos de matrizes Nelore criadas em regime extensivo sem suplementação, ao longo do sudoeste do estado do Piauí. Amostras de sangue foram coletadas de 55 fêmeas multíparas da raça Nelore. Os parâmetros bioquímicos e hematológicos foram analisados por método estatístico paramétrico com IC 95% para os limites de referência. Os valores médios de hemácias, hemoglobina e índices hematimétricos apresentaram intervalos de referência semelhantes aos padrões de referência. Tanto o hematócrito quanto os granulócitos e os agranulócitos apresentaram alterações típicas de animais criados em ambientes com temperaturas mais elevadas. Os perfis mineral, enzimático, proteico e metabólico foram semelhantes aos de outras raças bovinas, mas com uma faixa de valores mais estreita. No entanto, valores médios mais baixos foram observados para os níveis de cálcio ionizado, proteína total e ureia. Fêmeas Nelore apresentam perfis bioquímicos e hematológicos ligeiramente diferentes de outras raças, o que pode resultar dos manejos ambiental e nutricional aplicados e da deficiência natural de nitrogênio, fósforo e cálcio nas pastagens da região.(AU)

Grado de desarrollo del folículo preovulatorio y su relación con el tamaño del cuerpo lúteo y la producción de progesterona en las razas Romosinuano (RS) y Brahman (Br) / Degree of development of the preovulatory follicle and its relationship with corpus luteum size and progesterone production in the Romosinuano (RS) and Brahman (Br) breeds

RESUMEN Para comparar en los folículos preovulatorios de hembras bovinas de las razas Brahman (Br) y Romosinuano (RS) el desarrollo de los diferentes componentes foliculares, como el tamaño del antro folicular, el grosor y el volumen ocupado por la capa de células de la granulosa (CG) y de la teca interna (TI), y su posible relación con el desarrollo del cuerpo lúteo (CL) y la producción de progesterona P4, se utilizaron 5 hembras de la raza RS y 5 de la raza Br. A estas se les realizó seguimiento ecográfico durante 2 ciclos estrales y se les efectuó muestreo de suero sanguíneo para determinar por Elisa los niveles de P4. En el tercer estro se les extirpó el ovario que contenía el folículo preovulatorio y se realizó un corte diametral sobre el estigma del folículo para seccionarlo en 2 partes iguales. En una de las partes se hicieron cortes histológicos y se determinó la morfometría folicular. La duración del ciclo estral en las hembras de la raza Br osciló entre 18 y 21 días, con promedio de 19,9 ± 1,6 días, y en las vacas RS entre 18 y 24 días, con un promedio 21,2 ± 1,69 días. La duración del estro fue de 13,9 ± 6,98 y 9,60 ± 4,72 h para las razas RS y Br, respectivamente. El intervalo estro-ovulación fue de 21,20 ± 5,07 h para los animales de la raza Br y de 24,40 ± 6,43 para los RS. No se registraron diferencias entre razas ni en el grosor (RS: 55,12 ± 6,46 μm vs. Br: 49,48 ± 17,07 μm), p > 0,05, tampoco en el volumen ocupado por la capa de CG (RS: 27,93 ± 6,11 mm1 vs. Br: 25,40 ± 13,85 mm3) de los folículos preovulatorios p < 0,05, en el grosor (RS: 122,50 ± 20,53 μm vs. Br: 129,61 ± 84,85 μm) o en el volumen (RS: 64,97 ± 19,71 mm1 vs. Br: 59,83 ± 25,67 mm3) de las células de la TI. El máximo desarrollo de los CL para la totalidad de las hembras se alcanzó el día 12,6 ± 4,05 (día 0 = estro), con un diámetro promedio de 22,92 ± 3,60 mm. Para las de la raza RS el diámetro máximo fue 23,06 ± 3,9 mm y se observó en promedio el día 14,88 ± 3,4. Para las de la raza Br fue el día 10,00 ± 3,16 con un promedio de 22,75 ± 3,16 mm. En ese día, la concentración media de P4 fue de 5,37 ± 1,38 ng/ml para la raza RS y 5,74 ± 0,89 ng/ml para la raza Br. No se presentaron diferencias significativas entre razas (p > 0,05). Se concluyó que no existen diferencias en los eventos fisiológicos estudiados entre las razas RS y Br. Los hallazgos del presente estudio, sin duda, pueden servir de base para futuros análisis en los bovinos residentes en el trópico.

ABSTRACT To compare in the preovulatory follicles of bovine females of the Brahman (Br) and Romosinuano (RS) breeds the development of the different follicular components, such as the size of the follicular antrum, the thickness and volume occupied by the granulosa (CG) and theca interna cells (TI) layers and their possible relationships with the development of the corpus luteum (CL) and progesterone (P4) production, 5 RS and 5 Br females were used; ultrasound follow-up was performed during 2 estrous cycles and blood serum sampling was carried out to determine progesterone (P4) levels by Elisa, at the third estrus, the ovary containing the preovulatory follicle was removed, and a diametral cut was made on the stigma of the follicle to divide it into 2 equal parts. Histological sections were made of one of the parts and follicular morphometry was determined. Duration of the estrous cycle in Br females ranged between 18 and 21 days, with an average of 19,9 ± 1,6 days and between 18 and 24 with an average of 21,2 ± 1,69 days for RS cows. Estrus duration was 13,9 ± 6,98 and 9,60 ± 4,72 h for RS and Br breeds, respectively. The estrus-ovulation interval was 21,20 ± 5,07 h for the Br breed animals and 24,40 ± 6,43 RS. There were no differences between breeds or in thickness (RS: 55,12 ± 6,46 μm vs. Br: 49,48 ± 17,07 μm) p > 0,05, nor in the volume occupied by the granulosa cells layer (RS: 27,93 ± 6,11 mm3 vs. Br: 25,40 ± 13,85 mm3) of pre-ovulatory follicles; neither in the thickness (RS: 122,50 ± 20,53 vs. Br: 129,61 ± 84,85 μm) nor in the volume (RS: 64,97 ± 19,71 mm3 vs. Br: 59,83 ± 25,67 mm3) of the internal theca cells; p < 0,05. The maximum CL development for all the females was observed on day 12,6 ± 4,05 (day 0 = estrus), with an average diameter of 22,92 ± 3,60 mm. For those of the RS breed the maximum diameter was observed on average on day 14,88 ± 3,4, with 23,06 ± 3,9 mm, while for those of the Br breed it was day 10,00 ± 3,16 with an average diameter of 22,75 ± 3,16 mm; at this time the mean progesterone concentration was 5,37 ± 1,38 ng/ml for the RS breed and 5,74 ± 0,89 ng/ml for the Br breed. There were no significant differences between breeds (p-value: 0,5561). It was concluded that there are no differences in the physiological events studied between the studied breeds. Present results, undoubtedly, might serve as basis to future studies in bovines in tropical zones.

Hallazgos en tomografía computada de las complicaciones de la pancreatitis aguda / Findings of Acute Pancreatitis Complications on CT

Resumen La pancreatitis aguda es una patología inflamatoria del páncreas que se caracteriza por dolor abdominal y elevación de los niveles séricos de amilasa. Desde el punto de vista imagenológico, se la estudia con tomografía computada (TC), siendo esa la modalidad de elección para evaluar la extensión y la localización de las complicaciones. Según la gravedad, el tiempo de evolución y la extensión, hay distintos tipos de complicaciones y una variedad de hallazgos en TC.

Abstract Acute pancreatitis is an inflammatory pathology of the pancreas characterized by abdominal pain and elevated levels of serum amylase. In radiology, it is studied with computed tomography (CT), which is the preferred method to evaluate the extent and location of complications. Depending on the severity, time of evolution, and extent, there are different types of complications and a variety of findings on the CT scan.

Blood serum stability limit and maximum storage time of bovine samples

Measuring metabolic parameters in the blood has been an indispensable tool for assessing the productive and health status of dairy cows for more than 100 years. The values of laboratory parameters depend on various preanalytical, analytical and postanalytical factors. The most important preanalytical factors are sample transport time and temperature, hemolysis, anticoagulant type, and sample volume. Preanalytical factors can lead to reduced stability of the analyte in the sample, which changes their concentration. Loss of stability changes the time of storage and manipulation of the sample, which determines the criteria for its acceptance or rejection. The two stability indicators are stability limit and maximum permissible instability. A stability limit (SL) is defined as the period of time in which a property variation does not exceed a maximum permissible instability (MPI). The aim of this study was to determine the SL and MPI for each analyte in the blood serum of cows and to determine whether SL differs in the function of the presence of preanalytical errors in the blood sample. Three hundred samples of dairy cow origin in different periods of lactation participated in this research. They were classified into 6 groups of 50 samples: according to the time from sampling to processing in the laboratory (0-4 h, 4-8 h and over 8 h; all transported on dry ice, protected from environmental factors, without preanalytical errors) and according to the presence of preanalytical errors (group with hemolysis, a group transported at ambient temperature and a group with a small sample volume). Each sample was aliquoted in two portions. One portion was left at +4°C and tested once a day for 6 days of sample storage, and the second portion, placed at -20°C, was tested once a month for 6 months. The MPI had a value ranging from 1.51 to 8.4. Metabolic profile analytes with lower MPI values (1.51-3.22) were albumin (ALB), total protein (TPROT), UREA, glucose (GLU), calcium (Ca), and phosphorus (P). Higher MPI values (5.1-8.4) were found for nonesterified fatty acids (NEFA), beta-hydroxybutirate (BHB), cholesterol (CHOL), triglycerides (TGC), total bilirubin (TBIL) and aspartat aminotransferase (AST). For most parameters, we can conclude that their PD% changed faster in storage conditions at +4°C compared to the regime of -20°C. The largest number of biochemical analytes in bovine blood serum shows preserved stability in the first 6 days at +4°C or 6 months at -20°C if transported to the laboratory within 8 h after sampling in ideal conditions and without the action of preanalytical errors. Prolonged transport under ideal conditions or the existence of preanalytical errors such as transport at room temperature, hemolysis or small sample volume shorten the stability of the ALB, NEFA, GLU, UREA and P. Concentration of all analytes decreases during the stability test except for UREA, NEFA, BHB and for CHOL and TGC in some groups. Variations in parameters such as BHB, NEFA, TBIL, AST, and Ca have shown potential clinical significance. At storage conditions at +4°C, clinically significant variations at at least one measurement point were found for AST (7.5% of samples), BHB (6.1% of samples), NEFA (9.9% of samples) and for TBIL (in 7% of samples). This study can help define acceptable delay times and storage conditions for bovine blood samples, which is of great importance because in working with farm animals it is often not possible to take samples in a short time and deliver them to the laboratory, and samples are often burdened with certain preanalytical errors with limited possibilities of re-sampling.(AU)

Toward to establish selection criteria for rapid serological tests for COVID-19 / Hacia la construcción de criterios para la selección de pruebas serológicas rápidas para COVID-19

COVID-19, the new pandemic is associated to SARS-CoV-2 virus infection. Social distancing and the testing have been the principal measures that have shown to be effective for the reduction of critical cases. Although the gold standard for diagnosis of COVID-19 is the RT-PCR, rapid serological tests could also be used for prevalence studies, and for epidemiological monitoring. In order to characterize the humoral immune response, we analyzed eight immunochromatographic test and one ELISA test, as a verification or secondary validation analysis used positive and negative control serum samples. Sera from negative and positive individuals [asymptomatic or symptomatic individuals, outpatient or inpatientor (intensive care unit)] were analyzed, and the following results were found: of all these rapid tests, only 4 exhibit clear banding patterns for IgG and two of these also showed results for IgM (only in a few symptomatic patients). Instead, with an ELISA test a preferential recognition was observed for symptomatic patients who were critically ill, whereas in asymptomatic individuals it did not show more than 25% of positivity. Understanding and validating molecular and serological tests are an essential component for the design of public health measures to response to the pandemic.

COVID-19 la nueva pandemia está asociada con la infección por el virus SARS-CoV-2. La distancia social y el análisis masivo de muestras son las principales medidas que se han mostrado efectivas para la reducción de los casos críticos. Aunque el estándar de oro para el diagnóstico de COVID-19 es la RT-PCR, las pruebas serológicas rápidas podrían también ser usadas en estudios de prevalencia, así como en la vigilancia epidemiológica. Con el fin de caracterizar la respuesta inmune humoral, analizamos ocho pruebas inmunocromatográficas y una prueba de ELISA, en un proceso de verificación de desempeño o validación secundaria, usando sueros control positivos y negativos. Los sueros de pacientes positivos y negativos [individuos asintomáticos o sintomáticos, pacientes ambulatorios u hospitalizados (en cuidados intensivos)] fueron analizados, encontrando los siguientes resultados: de todas las pruebas rápidas examinadas solamente 4 mostraron un claro patrón de bandas para IgG, de éstas, dos de ellas también mostraron resultados para IgM (solamente en pocos pacientes sintomáticos). En cambio, con la prueba de ELISA un reconocimiento preferencial fue observado en pacientes sintomáticos con enfermedad crítica, mientras que los individuos asintomáticos no mostraron más de un 25 % de positividad. Comprender y validar las pruebas serológicas son componentes esenciales en el diseño de las medidas de políticas públicas como respuesta a esta pandemia.

Association of serum level of 25-hydroxy vitamin D with oral lichen planus: a case-control study / Asociación del nivel sérico de 25-hidroxi vitamina D con el liquen plano oral: un estudio de casos y controles

Introduction: Vitamin D deficiency is a global health problem that can be a risk factor for a broad range of diseases such as some autoimmune diseases. Due to the autoimmune base of lichen planus, it seems that a reduction of the serum level of vitamin D is related to lichen planus. In this study, we investigate the relation between serum level of vitamin D and oral lichen planus patients (OLP). Material and Methods: In this case-control study, 35 patients with OLP (including 15 men and 20 women) and 70 healthy volunteers (including 35 men and 35 women), aged between 30-60 years old, referred to Qazvin University of Medical Sciences were investigated. None of these volunteers had systemic diseases. Vitamin D levels were measured with ELFA (Enzyme Linked Fluorescent Assay) and the data was analyzed using the chi-squared test and t-test. Results: The mean serum level of vitamin D in the control group was 23.7±9ng/ml and in the case group was 18.12±8/7ng/ml. The results show that the serum level of vitamin D in patients with OLP is significantly less than in the control group (p<0.05). Conclusion: According to the results, the serum level of vitamin D in patients with OLP was significantly lower than that of healthy people.

Introducción: La deficiencia de vitamina D es un problema de salud global que puede ser un factor de riesgo para una amplia gama de enfermedades, como algunas enfermedades autoinmunes. Debido a la base autoinmune del liquen plano, parece que una reducción del nivel sérico de vitamina D está relacionada con el liquen plano. En este estudio, investigamos la relación entre el nivel sérico de vitamina D y los pacientes con liquen plano oral (LPO). Material y Métodos: En este estudio de casos y controles, 35 pacientes con LPO (incluidos 15 hombres y 20 mujeres) y 70 voluntarios sanos (incluidos 35 hombres y 35 mujeres), con edades comprendidas entre 30 y 60 años, remitieron a la Universidad de Medicina de Qazvin. Se investigaron las ciencias. Ninguno de estos voluntarios padecía enfermedades sistémicas. Los niveles de vitamina D se midieron con ELFA (ensayo fluorescente ligado a enzimas) y los datos se analizaron utilizando la prueba de chi-cuadrado y la prueba t. Resultados: El nivel sérico medio de vitamina D en el grupo de control fue de 23,7 ± 9 ng / ml y en el grupo de casos fue de 18,12 ± 8/7 ng / ml. Los resultados muestran que el nivel sérico de vitamina D en pacientes con OLP es significativamente menor que en el grupo de control (p<0.05). Conclusión: De acuerdo con los resultados, el nivel sérico de vitamina D en pacientes con LPO fue significativamente menor que en personas sanas.

Comparación de perfil lipídico por sexo y edad en una población de equinos en Caldas (Colombia) / Comparison of lipid profile by sex and age in an equine population in Caldas (Colombia)

RESUMEN Objetivo: comparar el perfil lipídico en equinos y analizar la correlación entre las cantidades lipídicas del suero de cuatro grupos. Materiales y Métodos: se obtuvieron muestras de sangre de 160 equinos en estado de ayuno, los cuales se diferenciaron por sexo y edad sin discriminar la raza así: machos jóvenes (40) y adultos (40), y hembras jóvenes (40) y adultas (40), las hembras no estaban preñadas; se determinaron los niveles de triglicéridos (TG), colesterol total (CT) y el colesterol de las lipoproteínas de alta densidad (C-HDL) mediante el método enzimático colorimétrico. El colesterol de las lipoproteínas de muy baja densidad (C-VLDL) y de baja densidad (C-LDL) se determinó usando las fórmulas de Friedewald. Los resultados se compararon mediante un análisis estadístico de Anova simple con el programa estadístico IBM SPSS Statistics 23®, donde se aceptaba diferencia estadísticamente significativa cuando p < 0,05. Resultados: las variables de CT, TG, C-HDL, C-LDL y C-VLDL del total de la población de acuerdo a la media y desviación estándar mostraron valores expresados en mg/dl de 100,3 ± 12,89; 45,59 ± 11,95; 62,03 ± 10,88; 27,91 ± 6,48; 9,11 ± 2. Al comparar los 4 grupos se encontró diferencia significativa en el C-HDL en los adultos (p-valor: 0,031), siendo mayor en las hembras adultas. Conclusiones: se presenta una diferencia estadísticamente significativa entre género para C-HDL siendo más alto en hembras adultas, mientras que para el resto de los elementos analizados (TG, CT, C-LDL, C-VLDL) no se encontró diferencia significativa entre género y edad.

ABSTRACT Objective: to compare the lipid profile in equines and to analyze the correlation bet-ween serum lipid amounts of four groups. Materials and Methods: Blood samples were obtained from 160 horses in the fasting state, they were differentiated by sex and age without discriminating race as follows: young (40) and adult males (40) and young (40) and adult females (40), the females were not pregnant; the levels of triglycerides (TG), total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C) were determined by the enzymatic colorimetric method. Very low density (C-VLDL) and low density (LDL-C) lipoprotein cholesterol was determined using the Friedewald formula. The results were compared using a statistical analysis of SIMPLE ANOVA with the statistical program IBM SPSS Statistics 23®, where a statistically significant difference was accepted when P < 0.05. Results: The variables of CT, TG, C-HDL, C-LDL and C-VLDL of the total population according to mean and standard deviation showed values expressed in mg/dl of100.3 ± 12.89; 45.59 ± 11.95; 62.03 ± 10.88; 27.91 ± 6.48; 9.11 ± 2. When comparing the 4 groups we found a significant difference in HDL-C in adults (p-value: 0.031), being higher in adult females. Conclusions: a statistically significant difference between genotype for HDL-C was found to be higher in adult females, whereas for the rest of the analyzed elements (TG, CT, C-LDL, C-VLDL) no significant difference between gender and age was found.

Neutralización de la actividad letal del veneno de serpiente Bothrops atrox por suero hiperinmune de llama (Lama glama) / Neutralization of the lethal activity from Bothrops atrox venom by hyperimune llama serum (Lama glama)

RESUMEN Objetivos: Evaluar la capacidad del suero hiperinmune de llama (Lama glama) para neutralizar la letalidad del veneno de la serpiente Bothrops atrox en ratones de laboratorio. Materiales y métodos: Se calculó la dosis letal media (DL50) de un pool de venenos de serpientes de Bothrops atrox de Perú, y se midieron los títulos de anticuerpos por ensayo ELISA; así como la potencia de neutralización del suero inmune por el cálculo de la dosis efectiva media (DE50) durante el periodo de inmunización. Resultados: La DL50 del veneno fue de 3,96 µg/g, similar a otros trabajos realizados en Bothrops atrox en Perú. Los títulos de anticuerpos contra el veneno se incrementan rápidamente en la llama mostrando una rápida respuesta inmune; sin embargo, la capacidad de neutralización se incrementa más lentamente y requiere de varias dosis y refuerzos de las inmunizaciones alcanzado una DE50 de 3,30 µL/g ratón y una potencia de neutralización 3,6 mg/mL después de 15 inmunizaciones. Conclusiones: El suero hiperinmune de llama es capaz de neutralizar la letalidad del veneno de la serpiente Bothrops atrox de Perú en ratones de laboratorio.

ABSTRACT Objectives: To evaluate the capacity of the hyperimmune llama serum (Lama glama) to neutralize the lethal activity of Bothrops atrox venom in laboratory mice. Materials and methods: Mean lethal dose (LD50) was calculated from a Bothrops atrox venom sample pool from Peru. The antibody titers were measured by ELISA assay; and the immune serum neutralization potency was measured by calculating the mean effective dose (ED50) during the immunization period. Results: The venom's LD50 was 3.96 μg/g; similar to what was found in other studies about Bothrops atrox carried out in Peru. The titers of antibodies against the venom increased rapidly in the llama, demonstrating a fast immune response; however, the neutralization capacity increased slowly and required several doses and immunization reinforcements, obtaining a ED50 of 3.30 μL/g mouse and a neutralization potency of 3.6 mg/mL after 15 immunizations. Conclusions: The hyperimmune llama serum is able to neutralize the lethality of the Bothrops atrox venom from Peru in laboratory mice.

Toxicity evaluation of water extract of tissue-cultured Taraxacum formosanum by acute, subacute administration, and Ames test

BACKGROUND: Taraxacum species (commonly known as dandelion) used as herbal medicine have been reported to exhibit an antiproliferative effect on hepatoma cells and antitumor activity in non-small-cell lung cancer cells. Although several investigations have demonstrated the safety of Taraxacum officinale, the safety of tissue-cultured plants of T. formosanum has not been assessed so far. Therefore, the present study examines the safety of the water extract of the entire plant of tissue cultured T. formosanum based on acute and subacute toxicity tests in rats, as well as the Ames tests. RESULTS: No death or toxicity symptoms were observed in the acute and subacute tests. The results of the acute test revealed that the LD50 (50% of lethal dose) value of the T. formosanum water extract for rats exceeded 5 g/kg bw. No abnormal changes in the body weight, weekly food consumption, organ weight, or hematological, biochemical, and morphological parameters were observed in the subacute toxicity test. Thus, the no observed adverse effect level (NOAEL) of T. formosanum water extract was estimated to be higher than 2.0 g/kg. Finally, the results of the Ames test revealed that T. formosanum water extract was not genotoxic at any tested concentration to any of five Salmonella strains. CONCLUSIONS: The water extract of tissue-cultured T. formosanum was non-toxic to rats in acute and subacute tests and exhibited no genotoxicity to five Salmonella strains.

Prevalencia del virus de la rinotraqueitis infecciosa bovina en el departamento del Caquetá, Amazonía Colombiana / Prevalence of bovine infectious rhinotracheitis virus in Caquetá department, Colombian Amazon

RESUMEN La rinotraqueitis infecciosa bovina (IBR) es una enfermedad ampliamente difundida en el mundo con gran repercusión socio-económica en las ganaderías bovinas. El objetivo del presente estudio fue determinar la prevalencia de IBR en 100 hatos del departamento del Caquetá, para lo cual, se muestrearon 960 bovinos mayores de 36 meses entre enero y marzo de 2016 en predios seleccionados a partir de los criterios: a) tamaño (50-180 hectáreas), b) con más de 10 vacas en ordeño, c) disponibilidad de los productores para cooperar y d) accesibilidad de las vías. Las muestras de suero sanguíneo se remitieron al Laboratorio de Diagnóstico Clínico Veterinario del ICA y se analizaron a través la prueba Elisa de bloqueo (BHV-1) gB. Los sueros con porcentaje de bloqueo superior al 55% se consideraron positivos a anticuerpos para IBR. Se encontró alta seroprevalencia (73,13%), mayor además en machos que en hembras (p < 0,05). A nivel municipal la seroprevalencia fue mayor en los municipios de El Doncello, Puerto Rico y San Vicente del Caguán y se encontró diferencia significativa (p < 0,05) entre los nueve municipios analizados. A nivel de hatos, la prevalencia fue del 99%. En conclusión, la prevalencia del virus de la rinotraqueitis infecciosa bovina (IBR) en bovinos de doble propósito del departamento del Caquetá fue muy alta.

ABSTRACT Infectious bovine rhinotracheitis (IBR) is a disease widely spread throughout the world with great socio-economic impact on bovine livestock. The objective of this study was to determine the prevalence of IBR in 100 herds in Caqueta department, for which 960 cattle older than 36 months between January and March 2016 were sampled in farms selected from the criteria: a) size (50-180 hectares), b) with more than 10 cows in milking, c) availability of producers to cooperate and d) accessibility of roads. Blood serum samples were sent to the ICA veterinary clinical diagnostic laboratory and analyzed using the Elisa blocking test (BHV-1) gB, where sera with blocking percentage greater than 55% were considered as positive for IBR antibodies. High seroprevalence was found (73.13%), being higher in males than in females (p < 0.05). At municipal level, seroprevalence was greater in El Doncello, Puerto Rico and San Vicente del Caguán municipalities, significant difference (p<0.05) was found between the nine municipalities analyzed. At herd level prevalence was of 99%. In conclusion the prevalence of Infectious Bovine Rhinotracheitis (IBR) virus in dual-purpose cattle of Caquetá department was very high.

Evaluation of serum and salivary transforming growth factor beta, vascular endothelial growth factor and tumor necrosis factor alpha in oral lichen planus / Evaluación sérica y salival del factor de crecimiento transformante beta, factor de crecimiento endotelial vascular y factor de necrosis tumoral alfa en liquen plano oral

Introduction: Lichen planus is one of the most common oral mucosal lesions. Transforming growth factor-ß (TGF- ß) has a marked effect on epithelial­mesenchymal transition and immune cells function. Vascular Endothelial Growth Factor (VEGF) is a key regulator of vasculogenesis and angiogenesis. Tumor necrosis factor-α (TNF-α) mediates T-lymphocyte homing and apoptosis of epithelial cells. Objetive: The present study was conducted in order to compare the expression of serum and salivary TGF- ß, VEGF, TNF-α between OLP patients and control individuals to investigate if saliva can be used as an alternative to serum for diagnostic purposes and for monitoring disease. Materials and Methods: 23 OLP patients and 23 control individuals were included to evaluate serum and salivary TGF-ß, VEGF, TNF-α using ELISA kits. Five milliliters of venous blood was collected and unstimulated saliva was collected by the spitting method. Results: Serum and salivary levels of TGF- ß, VEGF, TNF-α are higher in OLP patients compared to normal controls. Mean difference is higher in saliva than serum. Moreover, there was a significant difference in serum and salivary VEGF and TNF-α between symptomatic and asymptomatic groups. Conclusions: Saliva can be a used as a substitute for serum to evaluate levels of the assessed biomarkers.

Introducción: El liquen plano oral es una de las lesiones de la mucosa oral más comunes. El factor de crecimiento transformante ß (TGF-ß) tiene un efecto marcado sobre la transición epitelial-mesenquimal y la función de las células inmunes. El factor de crecimiento endotelial vascular (VEGF) es un regulador clave de la vasculogénesis y la angiogénesis. El factor de necrosis tumoral α (TNF-α) media la localización de los linfocitos T y la apoptosis de las células epiteliales. Objetivo: El presente estudio se realizó con el fin de comparar la expresión en suero y saliva de TGF-ß, VEGF, TNF-α entre pacientes con OLP y personas de control para investigar si la saliva se puede utilizar como alternativa al suero para fines de diagnóstico y monitoreo de la enfermedad. Material y Métodos: Se incluyeron 23 pacientes con OLP y 23 individuos control para evaluar los niéveles en suero y en saliva de TGF- ß, VEGF, TNF-α utilizando kits ELISA. Se recogieron cinco mililitros de sangre venosa y se recogió saliva no estimulada por el método de escupir. Resultado: Los niveles séricos y salivales de TGF-ß, VEGF, TNF-α son más altos en pacientes con OLP en comparación con los controles normales. La diferencia media es mayor en saliva que en suero. Además, hubo una diferencia significativa de VEGF y TNF-α en suero y saliva entre los grupos sintomáticos y asintomáticos. Conclusion: La saliva puede usarse como un sustituto del suero para evaluar los niveles de los biomarcadores estudiados

Analyzing weight evolution in mice infected by Trypanosoma cruzi

Concerning the specificities of a longitudinal study, the trajectories of a subject's mean responses not always present a linear behavior, which calls for tools that take into account the non-linearity of individual trajectories and that describe them towards associating possible random effects with each individual. Generalized additive mixed models (GAMMs) have come to solve this problem, since, in this class of models, it is possible to assign specific random effects to individuals, in addition to rewriting the linear term by summing unknown smooth functions, not parametrically specified, then using the P-splines smoothing technique. Thus, this article aims to introduce this methodology applied to a dataset referring to an experiment involving 57 Swiss mice infected by Trypanosoma cruzi, which had their weights monitored for 12 weeks. The analyses showed significant differences in the weight trajectory of the individuals by treatment group; besides, the assumptions required to validate the model were met. Therefore, it is possible to conclude that this methodology is satisfactory in modeling data of longitudinal sort, because, with this approach, in addition to the possibility of including fixed and random effects, these models allow adding complex correlation structures to residuals.