Tongue pressure is a strong predictor of recommendation for gastrostomy in amyotrophic lateral sclerosis.

INTRODUCTION/AIMS: Objective and practical biomarkers to determine the need for gastrostomy in patients with amyotrophic lateral sclerosis (ALS) are lacking. Tongue pressure (TP) is a promising biomarker because it is associated with bulbar dysfunction. The aims of this study were to evaluate the association of TP with the need for gastrostomy, and to determine its optimal cut-off value. METHODS: This prospective observational study included participants with ALS taking nutrition orally. TP was evaluated using the Iowa Oral Performance Instrument. Need for gastrostomy as determined by a multidisciplinary team during a 12-month follow up period was recorded. Associations between TP and need for gastrostomy placement were performed. ROC curve analysis determined the optimal cut-off value of TP to predict gastrostomy. RESULTS: Of 208 screened participants, 119 were included. Gastrostomy was indicated in 45% (53), in a 12-month follow up period. TP of ≤20 kPA was a strong predictor of gastrostomy indication (OR 11.8, CI 95% [4.61, 34.7], p < .001). The association persisted even after adjustment for weight loss, pneumonia, prolonged feeding duration, Revised ALS Functional Rating Scale score, and American Speech-Language-Hearing Association scale score (OR 4.51, CI 95% [1.50, 14.9], p = .009). By receiver operating characteristic curve analysis, 20 kPA represented the optimal cut-off value (sensitivity 0.75, specificity 0.89). DISCUSSION: TP is a strong independent predictor of gastrostomy indication in the subsequent 12 months in patients with ALS, with good sensitivity and specificity at a cutoff value of ≤20 kPA, suggesting that it may be a promising biomarker in clinical practice.

Intervention with a combined physical exercise training to reduce oxidative stress of women over 40 years of age.

Exercise training has been shown to be one of the most important lifestyle factor for improving functional performance and health status. Nevertheless, and although some evidence exists about the effects of aerobic training on oxidative stress, there is scarce information concerning the effects of combined exercise training (aerobic and strength training) in oxidative stress. Considering this, the aim of this study was to verify the effects of a combined exercise training in oxidative stress parameters of women over 40 years of age. At baseline, 67 women enrolled in the study and were divided into three groups: younger group (YG, n = 28: 40 to 49 years), middle-aged group (MAG, n = 21: 50 to 59 years) and oldest group (OG, n = 18: above 60 years). These women engaged in a combined exercise training program for 16 weeks, 3 sessions of 60 min per week. At the end of the program, only 31 women (YG: 15; MAG: 8 and OG: 8) were remained in the study and were considered for analysis. Physical assessments (weight, height, body mass index and waist circumference), health and functional parameters (systolic and diastolic blood pressure, fitness tests: supine, latissimus, squat jump, 8 foot up and go test, 30 second chair stand test, and 6 min walk test) and measures of DNA damage (DNA SBs, DNA netFPG), lipid peroxidation (MDA), total antioxidant capacity (TAC) and catalase activity (CAT) were performed before and after the 16-week intervention with combined exercise. The results showed an improvement of overall physical and functional performance as well as a significant decrease in waist perimeter and systolic blood pressure after the exercise program intervention. Regarding the biochemical measures, the exercise training induced a significant decrease in oxidative damage, and a significant increase in the TAC (p < 0.05). The results indicate that combined exercise training induces benefits in functional capacity and reduce damage caused by oxidative stress.

Resistance exercise protocol does not cause acute genotoxic effects in trained individuals / Protocolo de exercício resistido não provoca efeito genotóxico agudo em sujeitos treinados / Protocolo de ejercicio resistido no provoca efecto genotóxico agudo en sujetos entrenados

ABSTRACT Introduction: Resistance exercise, particularly strength training, has been progressively gaining more and more followers worldwide. Despite a considerable increase in the amount of research and literature available on this topic, resistance training is undergoing important developments. Anaerobic metabolism, which characterizes resistance training, enhances the ischemic process and blood reperfusion, thereby generating reactive oxygen species (ROS). The imbalance between the production of free radicals and antioxidant defenses may induce oxidative stress with subsequent protein oxidation, lipid peroxidation, DNA damage in several cells, and other effects. This process may be intensified at rest because the O2 deficit is counteracted by a process known as excess post-exercise oxygen consumption. Objective: To analyze the effects of ROS in strength training on the DNA of human lymphocyte, biomarkers of lipid damage (TBARS) and metabolism (triglycerides, protein, glycose, albumin and urea). Methods: Comet assay involving a count of 100 cells, which were divided into five classes of damage (no damage = 0, maximum damage = 4), thereby constituting an indication of DNA damage, and the micronucleus test, where the cell samples were centrifuged at 1000-1500 RPM for ten minutes at room temperature for the micronuclei analysis. Results: An elevation in triglyceride concentrations was observed 5h post-exercise (p=0.018), probably due to nutrition. There were no significant differences in the other biochemical parameters. In terms of the DNA damage measured by the Comet assay and micronucleus test, no statistical differences were observed until 5h post-exercise. Conclusion: The proposed training session did not cause oxidative or genotoxic damage in trained individuals under the proposed conditions. Level of Evidence II; Prognostic studies-Investigation of the effect of patient characteristics on the disease outcome.

RESUMO Introdução: O treinamento resistido, principalmente a musculação, vem progressivamente ganhando novos adeptos em todo o mundo. Apesar de haver um significativo aumento no número de pesquisas e na literatura disponível sobre o assunto, o treinamento resistido vem passando por um importante processo de evolução. O metabolismo anaeróbico, que caracteriza o treinamento resistido, acentua o processo de isquemia e a reperfusão sanguínea, gerando espécies reativas do oxigênio (ERO). O desequilíbrio entre a produção de radicais livres e as defesas antioxidantes pode desencadear estresse oxidativo e levar, entre outros, à oxidação de proteínas e à peroxidação de lipídios, além de danos no DNA de diversas células. Isso pode ser amplificado durante o repouso, pois o déficit de O2 é reposto por um processo denominado excesso de oxigênio consumido após exercícios. Objetivo: Analisar os efeitos de ERO em um treinamento de musculação sobre o DNA de linfócitos humanos, de biomarcadores de dano lipídico (TBARS) e de metabolismo (triglicerídeos, proteínas, glicose, albumina e ureia). Métodos: Teste Cometa mediante contagem de 100 células, as quais foram classificadas em cinco classes de dano (sem dano = 0, dano máximo = 4), constituindo, dessa maneira, um índice de dano no DNA e o teste de micronúcleo, no qual as amostras das células foram centrifugadas a 1000-1500 RPM por dez minutos em temperatura ambiente para a análise de micronúcleos. Resultados: Constatou-se elevação das concentrações de triglicerídeos após 5 horas do treinamento (p = 0,018), relacionada, provavelmente, à alimentação. Os demais parâmetros bioquímicos não mostraram diferenças significantes. Com relação ao dano provocado no DNA medido pelos testes Cometa e de micronúcleo, não se constatou diferença estatística até 5 horas após o treinamento. Conclusão: A sessão de treinamento proposto não provocou danos oxidativos nem genotóxicos em indivíduos treinados, nas condições propostas. Nível de Evidência II; Estudos prognósticos - Investigação do efeito de característica de um paciente sobre o desfecho da doença.

RESUMEN Introducción: El entrenamiento de resistencia, especialmente la musculación viene ganando progresivamente nuevos adeptos en todo el mundo. A pesar de haber un aumento significativo en el número de investigaciones y en la literatura sobre el tema, el entrenamiento de resistencia viene pasando por un importante proceso de evolución. El metabolismo anaeróbico, que caracteriza el entrenamiento de resistencia, acentúa el proceso de isquemia y la reperfusión sanguínea, generando especies reactivas de oxígeno (ERO). El desequilibrio entre la producción de radicales libres y las defensas antioxidantes puede desencadenar el estrés oxidativo y llevar, entre otros, a la oxidación de proteínas y peroxidación de lípidos, además de daño en el ADN de diferentes células. Eso puede ser amplificado durante el reposo, para el déficit de O2 es restablecido por un proceso denominado exceso de oxígeno consumido después de ejercicios. Objetivo: Analizar los efectos de ERO en un entrenamiento de musculación sobre el ADN de linfocitos humanos, de biomarcadores de daño lipídico (TBARS) y de metabolismo (triglicéridos, proteínas, glucosa, albúmina y urea). Métodos: Prueba Cometa a través de un recuento de 100 células, las cuales se clasificaron en cinco clases de daño (sin daño = 0, daño máximo = 4), constituyendo así un índice de daño en el ADN y la prueba de micronúcleo, en el cual las muestras de las células fueron centrifugadas a 1000-1500 RPM por diez minutos a temperatura ambiente para el análisis de micronúcleos. Resultados: Se constató elevación de las concentraciones de triglicéridos después de 5 horas del entrenamiento (p = 0,018), probablemente relacionada con la alimentación. Los demás parámetros bioquímicos no mostraron diferencias significativas. Con respecto al daño provocado en el ADN medido por las pruebas Cometa y de micronúcleos, no se constató diferencia estadística hasta 5 horas después del entrenamiento. Conclusión: La sesión de entrenamiento propuesto no provocó daño oxidativo ni genotóxico en individuos entrenados, en las condiciones propuestas. Nivel de evidencia II; Estudios pronósticos - Investigación del efecto de característica de un paciente sobre el desenlace de la enfermedad.

Brazilian Consensus for the Treatment of Multiple Sclerosis: Brazilian Academy of Neurology and Brazilian Committee on Treatment and Research in Multiple Sclerosis.

The expanding therapeutic arsenal in multiple sclerosis (MS) has allowed for more effective and personalized treatment, but the choice and management of disease-modifying therapies (DMTs) is becoming increasingly complex. In this context, experts from the Brazilian Committee on Treatment and Research in Multiple Sclerosis and the Neuroimmunology Scientific Department of the Brazilian Academy of Neurology have convened to establish this Brazilian Consensus for the Treatment of MS, based on their understanding that neurologists should be able to prescribe MS DMTs according to what is better for each patient, based on up-to-date evidence and practice. We herein propose practical recommendations for the treatment of MS, with the main focus on the choice and management of DMTs, as well as present a review of the scientific rationale supporting therapeutic strategies in MS.

Brazilian Consensus for the Treatment of Multiple Sclerosis: Brazilian Academy of Neurology and Brazilian Committee on Treatment and Research in Multiple Sclerosis / Consenso Brasileiro para o Tratamento da Esclerose Múltipla: Academia Brasileira de Neurologia e Comitê Brasileiro de Tratamento e Pesquisa em Esclerose Múltipla

ABSTRACT The expanding therapeutic arsenal in multiple sclerosis (MS) has allowed for more effective and personalized treatment, but the choice and management of disease-modifying therapies (DMTs) is becoming increasingly complex. In this context, experts from the Brazilian Committee on Treatment and Research in Multiple Sclerosis and the Neuroimmunology Scientific Department of the Brazilian Academy of Neurology have convened to establish this Brazilian Consensus for the Treatment of MS, based on their understanding that neurologists should be able to prescribe MS DMTs according to what is better for each patient, based on up-to-date evidence and practice. We herein propose practical recommendations for the treatment of MS, with the main focus on the choice and management of DMTs, as well as present a review of the scientific rationale supporting therapeutic strategies in MS.

RESUMO O crescent arsenal terapêutico na esclerose múltipla (EM) tem permitido tratamentos mais efetivos e personalizados, mas a escolha e o manejo das terapias modificadoras da doença (TMDs) tem se tornado cada vez mais complexos. Neste contexto, especialistas do Comitê Brasileiro de Tratamento e Pesquisa em Esclerose Múltipla e do Departamento Científico de Neuroimunologia da Academia Brasileira de Neurologia reuniram-se para estabelecer este Consenso Brasileiro para o Tratamento da EM, baseados no entendimento de que neurologistas devem ter a possibilidade de prescrever TMDs para EM de acordo com o que é melhor para cada paciente, com base em evidências e práticas atualizadas. Por meio deste documento, propomos recomendações práticas para o tratamento da EM, com foco principal na escolha e no manejo das TMDs, e revisamos os argumentos que embasam as estratégias de tratamento na EM.

Normative values of the Brief Repeatable Battery of Neuropsychological Tests in a Brazilian population sample: discrete and regression-based norms.

Objective Cognitive dysfunction is common in multiple sclerosis. The Brief Repeatable Battery of Neuropsychological Tests (BRB-N) was developed to assess cognitive functions most-frequently impaired in multiple sclerosis. However, normative values are lacking in Brazil. Therefore, we aimed to provide continuous and discrete normative values for the BRB-N in a Brazilian population sample. Methods We recruited 285 healthy individuals from the community at 10 Brazilian sites and applied the BRB-N version A in 237 participants and version B in 48 participants. Continuous norms were calculated with multiple-regression analysis. Results Mean raw scores and the 5th percentile for each neuropsychological measure are provided, stratified by age and educational level. Healthy participants' raw scores were converted to scaled scores, which were regressed on age, sex and education, yielding equations that can be used to calculate predicted scores. Conclusion Our normative data allow a more widespread use of the BRB-N in clinical practice and research.

Normative values of the Brief Repeatable Battery of Neuropsychological Tests in a Brazilian population sample: discrete and regression-based norms / Valores normativos da Brief Repeatable Battery of Neuropsychological Tests (BRB-N) em uma amostra da população Brasileira: dados discretos e contínuos

ABSTRACT Objective Cognitive dysfunction is common in multiple sclerosis. The Brief Repeatable Battery of Neuropsychological Tests (BRB-N) was developed to assess cognitive functions most-frequently impaired in multiple sclerosis. However, normative values are lacking in Brazil. Therefore, we aimed to provide continuous and discrete normative values for the BRB-N in a Brazilian population sample. Methods We recruited 285 healthy individuals from the community at 10 Brazilian sites and applied the BRB-N version A in 237 participants and version B in 48 participants. Continuous norms were calculated with multiple-regression analysis. Results Mean raw scores and the 5th percentile for each neuropsychological measure are provided, stratified by age and educational level. Healthy participants' raw scores were converted to scaled scores, which were regressed on age, sex and education, yielding equations that can be used to calculate predicted scores. Conclusion Our normative data allow a more widespread use of the BRB-N in clinical practice and research.

RESUMO Objetivo Disfunção cognitiva é comum em pacientes com esclerose múltipla. Por isto, a Brief Repeatable Battery of Neuropsychological Tests (BRB-N) foi desenvolvida para avaliar as funções cognitivas mais frequentemente alteradas na doença. Entretanto, estão faltando dados normativos desta bateria no Brasil. Assim, nosso objetivo foi fornecer valores normativos contínuos e discretos da BRB-N para a população brasileira. Métodos Foram recrutados 285 indivíduos sadios da comunidade em 10 centros do Brasil e aplicada a versão A em 237 e a versão B em 48 sujeitos. Normas contínuas foram calculadas com análise de regressão múltipla. Resultados Escores brutos médios e 5°percentil para cada subteste são fornecidos, estratificados por idade e nível educacional. Os escores brutos dos sujeitos sadios foram convertidos em escores de escalas e postos em regressão quanto a idade, sexo e educação, fornecendo equações que podem ser usadas para calcular escores previsíveis. Conclusão Nossos dados normativos permitem um uso mais amplo da BRB-N na prática clínica e na pesquisa, fornecendo normas para dados discretos e contínuos. Normas para dados discretos deveriam ser usadas com cuidado e escores demograficamente ajustados são geralmente preferidos quando interpretando dados neuropsicológicos.

Genetic analysis of patients with familial and sporadic amyotrophic lateral sclerosis in a Brazilian Research Center.

OBJECTIVE: To investigate gene mutations in familial form (FALS) and sporadic form (SALS) of amyotrophic lateral sclerosis (ALS) in a highly miscegenated population. METHODS: Frequencies of mutations in the C9orfF72, TARDBP, SOD1, FUS and VAPB genes were investigated in a cohort of FALS (n = 39) and SALS (n = 189) subjects from the Research Centre of the University of São Paulo School of Medicine. All patients were subjected to C9orf72 and TARDBP analyses. SOD1, FUS and VAPB were also evaluated in FALS subjects. RESULTS: Mutations were identified in FALS (61.3%) and SALS (5.3%) patients. Mutations in C9orf72 (12.8%, >45 GGGGCC hexanucleotide repeats), VAPB (43.6%, P56S) and SOD1 (7.7%, L145S) were identified in FALS subjects. Pathogenic C9orf72 expansions (2.64%) were identified in some SALS patients. Similar changes of TARDBP were found in SALS (2.64%) but not in FALS subjects. No FUS mutations were seen in any FALS subjects. CONCLUSIONS: TARDBP and C9orf72 mutations in this cohort were similar to those found in other centres worldwide. VAPB mutation (P56S) was highly prevalent in Brazilian FALS patients.

A disturbed processing of graviceptive pathways may be involved in the pathophysiology of balance disorders in patients with multiple sclerosis.

The purpose of this study was to determine the relationship between perception of verticality and balance disorders in multiple sclerosis patients. We evaluated patients and healthy controls. Patients were divided into two groups according to their risk of fall, with or without risk of fall, measured by a Dynamic Gait Index scale. Graviceptive perception was assessed using the subjective visual vertical test. Patients with risk of fall showed worse perception than those without risk of fall, p < 0.001. Misperception of verticality was correlated with the dynamic gait index scores (p < 0.001), suggesting that the larger the error for verticality judgment, the greater risk for falling. Considering that the perception of verticality is essential for postural control, our results suggested that the disturbed processing of graviceptive pathways may be involved in the pathophysiology of balance disorders in these patients.

A disturbed processing of graviceptive pathways may be involved in the pathophysiology of balance disorders in patients with multiple sclerosis / O processamento incorreto das informações graviceptivas pode estar envolvido na fisiopatologia dos distúrbios do equilíbrio em pacientes com esclerose múltipla

ABSTRACT The purpose of this study was to determine the relationship between perception of verticality and balance disorders in multiple sclerosis patients. We evaluated patients and healthy controls. Patients were divided into two groups according to their risk of fall, with or without risk of fall, measured by a Dynamic Gait Index scale. Graviceptive perception was assessed using the subjective visual vertical test. Patients with risk of fall showed worse perception than those without risk of fall, p < 0.001. Misperception of verticality was correlated with the dynamic gait index scores (p < 0.001), suggesting that the larger the error for verticality judgment, the greater risk for falling. Considering that the perception of verticality is essential for postural control, our results suggested that the disturbed processing of graviceptive pathways may be involved in the pathophysiology of balance disorders in these patients.

RESUMO Nosso objetivo foi determinar a relação entre percepção de verticalidade e alterações do equilíbrio em pacientes com esclerose múltipla (EM). Foram avaliados pacientes e sujeitos saudáveis. Pacientes foram divididos em dois grupos de acordo com o risco de queda, mensurado pelo Índice de marcha dinâmica, formando os grupos com risco e sem risco de quedas. A percepção da verticalidade foi medida através do teste vertical visual subjetiva (VVS). Pacientes com risco de queda apresentaram pior percepção da verticalidade quando comparados aos sem risco, p < 0,001. O desempenho no teste da VVS foi pior em pacientes quando comparado aos controles (p < 0,001). O erro no julgamento da verticalidade foi correlacionado aos índices de risco de queda (p < 0,001), sugerindo que quanto maior o erro no julgamento da verticalidade, maior o risco de queda dos pacientes. Nossos resultados sugerem que alterações das informações em vias graviceptivas podem estar envolvidas nas alterações de equilíbrio dessa população.

Gene expression profiling for human iPS-derived motor neurons from sporadic ALS patients reveals a strong association between mitochondrial functions and neurodegeneration.

Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease that leads to widespread motor neuron death, general palsy and respiratory failure. The most prevalent sporadic ALS form is not genetically inherited. Attempts to translate therapeutic strategies have failed because the described mechanisms of disease are based on animal models carrying specific gene mutations and thus do not address sporadic ALS. In order to achieve a better approach to study the human disease, human induced pluripotent stem cell (hiPSC)-differentiated motor neurons were obtained from motor nerve fibroblasts of sporadic ALS and non-ALS subjects using the STEMCCA Cre-Excisable Constitutive Polycistronic Lentivirus system and submitted to microarray analyses using a whole human genome platform. DAVID analyses of differentially expressed genes identified molecular function and biological process-related genes through Gene Ontology. REVIGO highlighted the related functions mRNA and DNA binding, GTP binding, transcription (co)-repressor activity, lipoprotein receptor binding, synapse organization, intracellular transport, mitotic cell cycle and cell death. KEGG showed pathways associated with Parkinson's disease and oxidative phosphorylation, highlighting iron homeostasis, neurotrophic functions, endosomal trafficking and ERK signaling. The analysis of most dysregulated genes and those representative of the majority of categorized genes indicates a strong association between mitochondrial function and cellular processes possibly related to motor neuron degeneration. In conclusion, iPSC-derived motor neurons from motor nerve fibroblasts of sporadic ALS patients may recapitulate key mechanisms of neurodegeneration and may offer an opportunity for translational investigation of sporadic ALS. Large gene profiling of differentiated motor neurons from sporadic ALS patients highlights mitochondrial participation in the establishment of autonomous mechanisms associated with sporadic ALS.

Cerebrospinal fluid aquaporin-4 antibody levels in neuromyelitis optica attacks.

To elucidate immunopathogenetic roles of aquaporin-4 antibodies in the cerebrospinal fluid (CSF) of neuromyelitis optica spectrum disorders (NMOSD), we analyzed aquaporin-4 antibody titers, cellular and inflammatory markers in the CSF collected from 11 aquaporin-4 antibody seropositive patients. The CSF aquaporin-4 antibody levels during attacks (but not in sera) closely correlated with pleocytosis, inflammatory cytokines including interleukin-6 that can regulate antibody-producing plasmablasts, and glial fibrillary acidic protein levels in the CSF. The amount of aquaporin-4 antibodies present in the central nervous system may have therapeutic implications, as it is associated with astrocyte injury and inflammatory responses during NMOSD attacks.

Distinction between MOG antibody-positive and AQP4 antibody-positive NMO spectrum disorders.

OBJECTIVE: To evaluate clinical features among patients with neuromyelitis optica spectrum disorders (NMOSD) who have myelin oligodendrocyte glycoprotein (MOG) antibodies, aquaporin-4 (AQP4) antibodies, or seronegativity for both antibodies. METHODS: Sera from patients diagnosed with NMOSD in 1 of 3 centers (2 sites in Brazil and 1 site in Japan) were tested for MOG and AQP4 antibodies using cell-based assays with live transfected cells. RESULTS: Among the 215 patients with NMOSD, 7.4% (16/215) were positive for MOG antibodies and 64.7% (139/215) were positive for AQP4 antibodies. No patients were positive for both antibodies. Patients with MOG antibodies represented 21.1% (16/76) of the patients negative for AQP4 antibodies. Compared with patients with AQP4 antibodies or patients who were seronegative, patients with MOG antibodies were more frequently male, had a more restricted phenotype (optic nerve more than spinal cord), more frequently had bilateral simultaneous optic neuritis, more often had a single attack, had spinal cord lesions distributed in the lower portion of the spinal cord, and usually demonstrated better functional recovery after an attack. CONCLUSIONS: Patients with NMOSD with MOG antibodies have distinct clinical features, fewer attacks, and better recovery than patients with AQP4 antibodies or patients seronegative for both antibodies.

Comparação do crescimento e desenvolvimento da alface (Lactuca sativa L) no interior e no exterior de uma estufa de polietileno em Santa Maria, RS / Comparison of Growth and development of lettüce plans (Lactuca sativa L) inside and outside of a polyethylene greenhouse in Santa Maria, RS

O trabalho teve por objetivo comparar o crescimento e o desenvolvimento das cultivares de alface Brasil- 202, White Boston e Regina, no interior e no exterior de uma estufa de polietileno durante o período de inverno em Santa Maria. A estufa permitiu um ganho térmico favorável ao crescimento da alface, da ordem de 256 graus-dia acima da temperatura base de crescimento de 10°C, durante o período de 50 dias. A temperatura do solo também foi mais favorável no interior da estufa, 5,3°C em média, em relação ao exterior. As plantas cultivadas no interior da estufa apresentaram curvas de crescimento similares àquelas cultivadas no exterior, porém com valores mais elevados dos parâmetros de crescimento de área foliar, massa verde da parte aérea, massa seca das folhas, do caule e das raízes. A relação parte aérea/sistema radiador também foi mais elevada no interior da estufa. O número de folhas por planta foi similar nos dois ambientes. Dentre as três cultivares testadas, a Brasil-202 apresentou maior precocidade e maior acumulação de massa seca. A estufa de polietileno mostrou ser uma alternativa eficiente para a produção de alface nos meses de inverno.

Growth and development of lettuce cultivar Brasil- 202, White Boston and Regina inside and outside of a polyethylene greenhouse were compared in Santa Maria, RS. During a winter period of 50 days the greenhouse caused an increase in about 256 degree-days in the temperature values above the base temperature for growth (estimated in 10°C). Mean soil temperature was also 5.3°C higher inside the greenhouse. The growth patterns of plants cultivated inside the greenhouse were similar to those cultivated outside. Growth parameters of leaf surface, shoot fresh weight, dry weight of leaves. stem and roots and the shoot/root ratio were lower outside the greenhouse. The number of leaves per plant was similar in both conditions. Brasil-202 showed earlier growth and higher dry matter accumulation. Protection of plants with polyethylene greenhouses is an efficient technique to improve lettuce crop production in winter.