Middle-age abolishes cardioprotection conferred by thioredoxin-1 in mice.

Thioredoxin-1 (Trx1) has cardioprotective effects on ischemia/reperfusion (I/R) injury, although its role in ischemic postconditioning (PostC) in middle-aged mice is not understood. This study aimed to evaluate if combining two cardioprotective strategies, such as Trx1 overexpression and PostC, could exert a synergistic effect in reducing infarct size in middle-aged mice. Young or middle-aged wild-type mice (Wt), transgenic mice overexpressing Trx1, and dominant negative (DN-Trx1) mutant of Trx1 mice were used. Mice hearts were subjected to I/R or PostC protocol. Infarct size, hydrogen peroxide (H2O2) production, protein nitration, Trx1 activity, mitochondrial function, and Trx1, pAkt and pGSK3ß expression were measured. PostC could not reduce infarct size even in the presence of Trx1 overexpression in middle-aged mice. This finding was accompanied by a lack of Akt and GSK3ß phosphorylation, and Trx1 expression (in Wt group). Trx1 activity was diminished and H2O2 production and protein nitration were increased in middle-age. The respiratory control rate dropped after I/R in Wt-Young and PostC restored this value, but not in middle-aged groups. Our results showed that Trx1 plays a key role in the PostC protection mechanism in young but not middle-aged mice, even in the presence of Trx1 overexpression.

Effect of irrigation acid solutions on cleaning and bond strength to post-space dentin.

This study evaluated the effects of irrigating solutions containing 5% boric acid + 1% citric acid or 1% peracetic acid + high concentration hydrogen peroxide on root cleaning and bond strength of cementation systems after 24 h and 6 months of glass fiber post cementation. One hundred and twenty roots were endodontically treated. The specimens were randomized into one of four treatments (n = 10): DW (distilled water); NaOCl2.5% + EDTA17% (2.5% sodium hypochlorite solution + 17% EDTA); PA1% + HP (1% peracetic acid solution + high concentration of hydrogen peroxide); BA5% + CA1% (5% boric acid associated with 1% citric acid). The cleaning efficacy in the cervical, middle, and apical thirds of the post-space, and the push-out bond strength at 24 h and 6 months after post cementation were evaluated by Kruskal-Wallis and two-way ANOVA tests, respectively. BA5% + CA1% showed statistically significantly superior cleaning efficacy compared to the other solutions. This irrigation protocol also resulted in higher bond strength at 24 h and 6 months, regardless of the root third considered, and this was statistically significantly higher than those seen for DW and PA1% + HP. For BA5% + CA1% irrigation protocol, type 1 adhesive failure was the most prevalent. Post-space irrigation with BA5% + CA1% provided both higher cleaning efficacy and better bond strength.

Retronychia: an underdiagnosed disease.

Retronychia is a recently described cause of ingrowth of the nail plate on the ventral surface of the proximal nail fold. Clinical features are repeated episodes of proximal paronychia, nail plate thickening, and occasionally granulation tissue emergence. The usual treatments for paronychia such as antibiotics and antifungals are ineffective in these cases. Avulsion of the nail plate is the treatment of choice for these patients, but effective treatment is usually delayed owing to inadequate diagnosis. Herein, we describe a 28-year-old woman with a case of retronychia. She was treated for two months with oral and topical antifungal and antibiotics by her general practitioner. After proper diagnosis and avulsion of the nail she presented a normal and non-painful growth of the affected nail.

Clinical performance of sealants under different humidity control conditions: a split-mouth 1-year randomized trial.

PURPOSE: Sealants are an effective method of prevention and treatment for early caries lesions. This study analyzed the 1-year clinical performance of resin-based and ionomeric sealants applied to permanent teeth under different humidity conditions. METHODS: The investigation was a triple-blind randomized clinical trial (RCT) with a four arms split-mouth design, divided according to the sealant protocol: (1) Resin-based sealant applied with rubber dam isolation, (2) Resin-based sealant applied with cotton rolls isolation, (3) Ionomeric sealant applied with rubber dam isolation and (4) Ionomeric sealant applied with cotton rolls isolation. Fifty-eight patients started the study (232 teeth), and 47 (188 teeth) remained until the 1-year recall. The modified USPHS criteria were used in the analyzes to investigate surface texture, retention and the presence of secondary caries lesions around the sealants; in the following periods: baseline, after 3, 6, 9, and 12 months by two calibrated examiners. Data were analyzed by the Mann-Whitney and Friedman tests. RESULTS: There was no difference between the types of sealants (p > 0.05). The type of humidity control influenced the superficial texture (p = 0.0012) and the retention of sealants (p = 0.0023). The sealant displacement was greater under cotton rolls isolation. Only one active caries lesion in enamel was found in the 9th month. CONCLUSION: It may be concluded that sealants effectively prevented caries, even when they were partially or totally lost, regardless of the material. The rubber dam isolation with a rubber dam promoted lower surface roughness and improved the retention rates. International Clinical Trials Registry Platform: #1111-1215-2832 (07/26/2018).

Indicadores de sustentabilidade socioambiental de pisciculturas familiares em área de Mata Atlântica, no Vale do Ribeira - SP / Social and Environmental Indicators of Family Fish Farms in the Atlantic Forest area in the Ribeira Valley - SP

O objetivo deste trabalho consistiu na aplicação de indicadores socioambientais em pisciculturas familiares localizadas na região do Vale do Ribeira, em área de Mata Atlântica, no sudoeste do estado de São Paulo. Para isso, foram identificadas 84 propriedades. Dessas, 40 foram selecionadas como unidades amostrais. Entre as principais características identificadas, 32% possuem lâmina d'água inferior a cinco hectares, com viveiros escavados em sistema semi-intensivo, 58% utilizam mão de obra familiar e 23% apontam a ausência de assistência técnica especializada como o principal problema enfrentado. A tilápia-do-nilo (Oreochromis niloticus) representa 57% das espécies produzidas em sistemas de monocultivo ou policultivo. Contudo, as pisciculturas familiares são classificadas como sistemas produtivos de pequeno porte, com destaque para a necessidade de adequação de recursos naturais, da capacidade de gestão e da eficiência das práticas de produção. Os indicadores sociais variaram de 0,75 a 1,00 para equidade salarial, proporção de autoemprego, uso de mão de obra local, inclusão de gênero e inclusão etária, demonstrando a capacidade que a aquicultura tem para auxiliar no desenvolvimento social local, por meio da geração de emprego e renda.(AU)

The objective of this work was to apply socioenvironmental indicators in family fish farms located in the Ribeira Valley region, Atlantic Forest area, southwest of São Paulo state, Brazil. Thus, we identified 84 production units. Of these, we selected 40 as sample units. Among the main characteristics identified, 32% have water depth of less than five hectares with excavated ponds in semi-intensive system, 58% use family labor and 23% report the lack of specialized technical assistance as the main problem faced. The Nile tilapia (Oreochromis niloticus) represents 57% of the species produced in monoculture or polyculture systems. Therefore, family fish farms are classified as small production systems with emphasis on the need to adapt natural resources, management capacity and efficiency of production practices. Social indicators ranged from 0.75 to 1.00 for salary equity, proportion of self-employment, use of local labor, gender inclusion and age inclusion, demonstrating the ability of aquaculture to assist local social development through job and income generation.(AU)

[Paratesticular tumor. Liposarcoma of the spermatic cord]. / Tumor paratesticular. Liposarcoma del cordón espermático.

Liposarcoma of the spermatic cord is a rare tumour typically presenting in elderly people. It tends to grow around blood vessels. Most of them have a low level of malignancy and relapses tend to be localized. Metastasis, when present, occur through the haematological route, lymph spread being very unusual. Pre-operative diagnosis is infrequent and overall prognosis is good. The choice treatment is radical orchidectomy, while long-term follow-up of these patients is mandatory. When local relapses become evident, the choice treatment is extensive local excision, followed by optional adjuvant radiotherapy. Chemotherapy has not proven to be effective. This paper reviews the current literature and contributes one case of mixed liposarcoma of the spermatic cord.

[Lipid peroxidation following ultraviolet irradiation of the blood and the protective action of tocopherol acetate (experimental research)]. / Sostoianie perekisnogo okisleniia lipidov posle ul'trafioletovogo oblucheniia krovi i zashchitnoe deistvie tokoferola atsetata (éksperimental'noe issledovanie).

Original experimental data are reported on processes occurring in the blood after UV irradiation. A study of the content of primary and secondary products of lipid peroxidation, vitamin E and the resistance of erythrocytes to hemolysis, catalase activity before and after UV irradiation of animals of different age groups revealed that UV irradiation of the blood changes not only the intensity of the process of lipid peroxidation but also the direction of metabolism of unsaturated fatty acids in the blood cells, exchange of semiproducts between them and the plasma, but also weakens the antioxidant systems of the blood. These processes are age-dependent. Preliminary administration of vitamin E preparations secures a high antioxidant homeostasis in the blood, especially after UV irradiation.

Caracterización de la interconsulta médico-psicológica en un hospital pediátrico de alta complejidad / Characterization of the medical-psychological consultation at a tertiary pediatric hospital

Durante los meses de febrero a mayo de 2014 se caracterizaron las interconsultas de pacientes del área de internación que no eran atendidos por equipos interdisciplinarios y por los que se consultaba por primera vez, realizadas por los becarios del Servicio de Salud Mental (SSM). Se analizaron los datos ociobiodemográficos de los pacientes, las categorías de los pedidos y los diagnósticos e intervenciones por parte del servicio de salud mental. También se analizó la coincidencia de los diagnósticos realizados por los pediatras solicitantes con los realizados por los especialistas. La muestra total quedó constituida por 62 pacientes, 53% de sexo masculino, 70% proveniente del conurbano. Los pediatras consideraron que el 94% de las consultas debían realizarse en el día. El pedido más frecuente fue el requerimiento de atención por síntomas psicopatológicos en el niño (45%), seguidos por el malestar en el niño inherente a la situación de enfermar (21%). De los síntomas psicopatológicos, los conversivos fueron los más frecuentes. En el 8% de los casos el especialista consideró luego de la evaluación que la interconsulta no era pertinente. En el 41% de los casos existió total coincidencia en el diagnóstico realizado por el pediatra y por el especialista. Los especialistas diagnosticaron 6% menos síntomas psicopatológicos que los pediatras en los niños, y 5% más en los padres. La intervención más utilizada fue la psicoterapéutica (90%). Solo requirieron farmacoterapia el 10% de los pacientes. El 86% de las consultas requirieron seguimiento durante la internación y el 26%, continuar de manera ambulatoria tras el alta (AU)

Between February and May 2014 consultations from the inpatient area for children who were not managed by multidisciplinary teams and who were consulted for the first time were evaluated by fellows from the Department of Mental Health. Sociodemographic data of the patients, consultation categories, diagnoses, and interventions by the Mental Health team were analyzed. Coincidence between the diagnosis made by the pediatricians who requested the consultation and that made by the specialists was also assessed. The total sample consisted of 62 patients; 53% were male and 70% came from Greater Buenos Aires. The pediatricians considered that 94% of the children needed consultation on the same day. The most common request for consultation was because of psychopathological symptoms in the child (45%), followed by disease-related discomfort in the child (21%). Conversion symptoms were the most common psychopathological symptoms observed. In 8% of the cases, after evaluation the specialist did not consider the consultation necessary. In 41% of the cases the diagnosis of the specialist coincided with that of the pediatrician. Specialists diagnosed 6% less psychopathological symptoms in children and 5% more in parents compared to pediatricians. The most commonly used intervention was psychotherapy (90%). Only 10% of the patients required pharmacotherapy. Overall, 86% of the consultations required follow-up during hospital stay and in 26% of the patients, follow-up in an outpatient setting was necessary (AU)

Electroglottography of speakers of Brazilian Portuguese through Objective Multiparameter Vocal Assessment (EVA).

UNLABELLED: EVA was designed to study various speech production parameters. OBJECTIVE: This paper aims to define the mean values for electroglottography tests of Brazilian Portuguese speakers on EVA. MATERIALS AND METHOD: The voices of 20 men and 20 women without voice-related complaints were analyzed through electroglottography so as to obtain reference values for normality. CASE STUDY: this is a descriptive cross-sectional study. RESULTS: The mean values for normal male voices were: F0 = 127.77 Hz; F0 coefficient of variation = 2.51%; absolute jitter = 1.707 Hz; relative average perturbation = 0.0083; jitter factor = 1.34%; jitter ratio = 13.45%; QF = 0.447. The values for female voices were: F0 = 204.87 Hz; F0 coefficient of variation = 1.58%; absolute jitter = 3.30Hz; relative average perturbation = 0.0102; jitter factor = 1.60%; jitter ratio = 16.23%; QF= 0.443. Wave type for the entire sample was categorized as tilted pulse. CONCLUSION: Statistically significant differences were found for gender on parameters average FO and absolute jitter. While using acoustic analysis software, users must be based on parameters inherent to the software program when analyzing the collected data.

Análise das medidas aerodinâmicas no português brasileiro por meio do método multiparamétrico de avaliação vocal objetiva assistida (EVA) / Analysis of aerodynamic measures in Brazilian portuguese through multiparameter assessment method vocal objective assist (EVA)

OBJETIVO: definir medidas aerodinâmicas em falantes do português brasileiro, sem queixas vocais, obtidas pelo programa EVA. MÉTODO: participaram do estudo 20 homens e 20 mulheres, que tiveram suas vozes analisadas. RESULTADOS: os valores médios referentes à pressão subglótica para vozes femininas e masculinas foram, respectivamente: Pressão subglótica= 5,84 hPa e 6,7 hPa, média da intensidade= 79,21 dB e 81,7 dB, média do fluxo oral= 0,09 dm³/s e 0,16 dm³/s, eficiência glótica= 13,87 dB/hPa e 12,78 dB/hPa, eficiência laríngea= 188,08 dB/(hPa.dm³/s) e 97,11 dB/(hPa.dm³/s), resistência laríngea= 96,26 hPa/(dm³/s) e 52,64 hPa/(dm³/s), média da frequência fundamental (F0)= 208,28 Hz e 136,56 Hz e pico da pressão do fluxo oral= 0,093 e 0,098. Houve diferença estatisticamente significante em relação ao gênero para as medidas de média de intensidade, eficiência laríngea, resistência laríngea e média da frequência fundamental. Os valores médios referentes ao fluxo oral para vozes femininas e masculinas foram respectivamente: Pressão subglótica= 6,05 hPa e 6,6 hPa, média da intensidade= 65,50 dB e 66,3 dB, média do fluxo oral= 0,10 dm³/s e 0,13 dm³/s, eficiência glótica= 11,12 dB/hPa e 11,77 dB/hPa, eficiência laríngea= 144,83 dB/(hPa.dm³/s) e 97,89 dB/(hPa.dm³/s), resistência laríngea= 78,98 hPa/(dm³/s) e 61,81 hPa/(dm³/s), média da F0= 222,52 Hz e 139,20 Hz e pico da pressão do fluxo oral= 0,047 e 0,053. CONCLUSÃO: o EVA é um programa ainda novo no Brasil, e a análise de medidas aerodinâmicas, em falantes do português brasileiro, permite a obtenção de valores de referência, possibilitando assim comparações com estudos futuros.

PURPOSE: to define aerodynamic measures in Brazilian Portuguese speakers without voice complaints, obtained by the EVA program. METHOD: the study included 20 men and 20 women who had their voices analyzed. RESULTS: the mean values with subglottic pressure for female and male voices were: Subglottic pressure = 5.84 hPa and 6.7 hPa; average intensity = 79.21dB and 81.7dB; oral mean flow = 0.09 dm3/s and 0.16 dm3/s; glottic efficiency = 13.87dB/hPa and 12.78 dB/hPa; laryngeal efficiency = 188.08 dB/(hPa.dm3/s) and 97.11dB/(hPa.dm3/s); laryngeal resistance = 96.26 hPa/(dm3/s) and 52.64 hPa/(dm3/s); mean fundamental frequency (F0) = 208.28 Hz and 136.56 Hz and peak mouth pressure flow = 0.093 and 0.098. There was a statistically significant difference in relation to gender for the measures of average intensity, efficiency, larynx, laryngeal resistance and mean fundamental frequency. The average flow for the oral female and male voices were: subglottic pressure = 6.05 hPa and 6.6 hPa; average intensity = 65.50 dB and 66.3 dB; oral mean flow = 0, 10 dm3/s and 0.13 dm3/s; glottic efficiency = 11.12 dB/hPa and 11.77 dB/hPa; laryngeal efficiency = 144.83 dB/( hPa.dm3/s) and 97.89 dB/( hPa.dm3/s); laryngeal resistance = 78.98 hPa/(dm3/s) and 61.81 hPa/( dm3/s); average F0 = 222.52 Hz and 139.20 Hz and peak pressure oral flow = 0.047 and 0.053. CONCLUSION: EVA is a new program in Brazil, and analysing the aerodynamic measures in Brazilian Portuguese speakers, allows us to obtain reference values, thus allowing comparisons with future studies.

Medidas eletroglotográficas em falantes do português brasileiro por meio do Método Multiparamétrico de Avaliação Vocal Objetiva Assistida (EVA) / Electroglottography of speakers of Brazilian Portuguese through Objective Multiparameter Vocal Assessment (EVA)

O Método Multiparamétrico de Avaliação Vocal Objetiva Assistida (EVA) foi projetado para o estudo da maioria dos parâmetros de produção da fala. OBJETIVO: Definir as medidas médias dos parâmetros eletroglotográficos em falantes do português brasileiro para o EVA. MATERIAL E MÉTODO: Foram analisadas 40 vozes, 20 homens e 20 mulheres sem queixa vocal, extraindo-se as medidas eletroglotográficas, a fim de obter valores de referência de normalidade. Estudo de caso: estudo descritivo com corte transversal. RESULTADOS: Os valores médios de normalidade encontrados nas vozes masculinas foram: F0 = 127,77 Hz, coeficiente de variação de F0 = 2,51%, jitter absoluto = 1,707 Hz, perturbação média relativa = 0,0083, jitter factor = 1,34%, jitter ratio = 13,45%, e QF = 0,447. Para vozes femininas, foram: F0 = 204,87 Hz, coeficiente de variação de F0 = 1,58%, jitterabsoluto = 3,30 Hz, perturbação média relativa = 0,0102, jitter factor = 1,60%, jitter ratio = 16,23%, e QF = 0,443. O tipo de onda foi em 100% da amostra classificada como pulso inclinado em ambos os gêneros. CONCLUSÃO: Houve diferença estatisticamente significante em relação ao gênero para os parâmetros de média F0 e jitterabsoluto. Ao utilizar um programa de análise acústica, os usuários devem basear-se em parâmetros inerentes ao próprio programa para realizar a análise dos dados coletados.

EVA was designed to study various speech production parameters. OBJECTIVE: This paper aims to define the mean values for electroglottography tests of Brazilian Portuguese speakers on EVA. MATERIALS AND METHOD: The voices of 20 men and 20 women without voice-related complaints were analyzed through electroglottography so as to obtain reference values for normality. Case study: this is a descriptive cross-sectional study. RESULTS: The mean values for normal male voices were: F0 = 127.77 Hz; F0 coefficient of variation = 2.51%; absolute jitter = 1.707 Hz; relative average perturbation = 0.0083; jitter factor = 1.34%; jitter ratio = 13.45%; QF = 0.447. The values for female voices were: F0 = 204.87 Hz; F0 coefficient of variation = 1.58%; absolute jitter = 3.30Hz; relative average perturbation = 0.0102; jitter factor = 1.60%; jitter ratio = 16.23%; QF= 0.443. Wave type for the entire sample was categorized as tilted pulse. CONCLUSION: Statistically significant differences were found for gender on parameters average FO and absolute jitter. While using acoustic analysis software, users must be based on parameters inherent to the software program when analyzing the collected data.

Comparison of intervention strategies for control of Triatoma dimidiata in Nicaragua.

The effectiveness of three operational strategies for the control of Triatoma dimidiata was compared by a field trial in the Department of Madriz, Nicaragua. One strategy involved full pretrial evaluation, followed by spraying of all houses irrespective of whether or not they had been found to be infested. The second strategy minimised the pretrial evaluation by considering the locality infested as soon as one house was found to be positive, followed by spraying all houses. The third strategy involved full pretrial evaluation, followed by spraying only those houses found to be positive. Evaluation after twelve months indicated that all three strategies were similarly effective, since all sprayed houses remained free of infestation. However, comparative estimates of the unit intervention costs indicated that strategies 1 and 2 were substantially less efficient than the third strategy of spraying only positive houses.

Hydergine and vincamine derivative LD 4298 exhibit no anti-sickling properties in vitro.

Amongst the treatments proposed for Sickle Cell disease Ergot derivatives and extracts from Pervinca have been proposed. We have studied in vitro the effect of Hydergine and LD 4298 on Sickle Cells and Sickle Hemoglobin according to the following four parameters : percentage of sickling, potassium leak, minimum gelation concentration and speed of gelation. In these studies no anti-sickling effect was detected. Moreover Hydergine at 50 microgram/ml increased spontaneous potassium loss without any anti-sickling effect. One can conclude that these two drugs have no effect on sickling.

Hydergine and vincamine derivative LD 4298 exhibit no anti-sickling properties in vitro.

Amongst the treatments proposed for Sickle Cell disease Ergot derivatives and extracts from Pervinca have been proposed. We have studied in vitro the effect of Hydergine and LD 4298 on Sickle Cells and Sickle Hemoglobin according to the following four parameters: percentage of sickling, potassium leak, minimum gelation concentration and speed of gelation. In these studies no anti-sickling effect was detected. Moreover Hydergine at 50 microgram/ml increased spontaneous potassium loss without any anti-sickling effect. One can conclude that these two drugs have no effect on sickling.

Characteristics of elderly inpatients at high risk of needing supportive social and health care services.

A two-stage cross-sectional study was conducted in a 951-bed acute-care hospital: a first survey designed to determine the profile of patients aged > or = 64 years needing supportive social/health care services, in which 38 patients discharged between June and July, 1992 (group 1) with social/health care problems that accounted for inappropriate hospitalization days participated, and a second survey designed to identify patients aged > or = 65 years at high risk and thus facilitating the early intervention of social workers, in which 153 patients selected at random and interviewed between August and September, 1992 (group 2) participated. A significantly higher percentage of group 1 patients had no medical insurance, were admitted to hospital for treatment, lived alone, had been readmitted in the previous 6 months, suffered from dementia and/or cognitive impairment, presented with associated chronic illnesses, and showed lower Barthel index scores as compared to group 2 patients. In patients in group 2, hospital discharge was delayed due to the need of supportive social and health care services in only 27 patients. The percentage of agreement in the suitability of the resource provided was higher after (92.6%) than before the intervention (71.1%). The mean number of inappropriate hospitalization days was 3.5 days for patients in group 1 and 1.9 days for those in group 2 (p = 0.013). The early identification of elderly inpatients at high risk of needing additional supportive social and health care would help patients to find the most appropriate resource according to their individuals needs.

Comparison of Intervention Strategies for Control of Triatoma dimidiata in Nicaragua

The effectiveness of three operational strategies for the control of Triatoma dimidiata was compared by a field trial in the Department of Madriz, Nicaragua. One strategy involved full pretrial evaluation, followed by spraying of all houses irrespective of whether or not they had been found to be infested. The second strategy minimised the pretrial evaluation by considering the locality infested as soon as one house was found to be positive, followed by spraying all houses. The third strategy involved full pretrial evaluation, followed by spraying only those houses found to be positive. Evaluation after twelve months indicated that all three strategies were similarly effective, since all sprayed houses remained free of infestation. However, comparative estimates of the unit intervention costs indicated that strategies 1 and 2 were substantially less efficient than the third strategy of spraying only positive houses

Comparison of intervention strategies for control of Triatoma dimidiata in Nicaragua

The effectiveness of three operational strategies for the control of Triatoma dimidiata was compared by a field trial in the Department of Madriz, Nicaragua. One strategy involved full pretrial evaluation, followed by spraying of all houses irrespective of whether or not they had been found to be infested. The second strategy minimised the pretrial evaluation by considering the locality infested as soon as one house was found to be positive, followed by spraying all houses. The third strategy involved full pretrial evaluation, followed by spraying only those houses found to be positive. Evaluation after twelve months indicated that all three strategies were similarly effective, since all sprayed houses remained free of infestation. However, comparative estimates of the unit intervention costs indicated that strategies 1 and 2 were substantially less efficient than the third strategy of spraying only positive houses

Un modelo didáctico no presencial para la enseñanza de anatomía veterinaria / A not presential didactic model for teaching veterinary anatomy

¿Es posible generar una propuesta académica de Anatomía Veterinaria que brinde alternativas a los jóvenes deseosos de estudiar y que por distintas cuestiones (problemas laborales, impedimentos físicos, superposiciones horarias, etc.) no tengan alternativas para hacerlo? Para dar respuesta a esta interrogante y con la intención de aportar una solución, en la Facultad de Agronomía y Veterinaria de la Universidad Nacional del Litoral (Santa Fe, Argentina), se desarrolló un proyecto de investigación en el que se ha implementado una modalidad didáctica no presencial que intenta subsanar los inconvenientes planteados por la rigidez del sistema presencial. Mediante un sistema de estructuras modulares, tutorías permanentes y un mecanismo de autoevaluación continua y eficaz se han obtenido buenos resultados que confirman la hipótesis de que se puede realizar una oferta educativa de buen nivel, accesible para aquellos que margina el sistema áulico convencional