ABSTRACT Using a random block design and four replications with six treatments consisting on regrowth ages (30, 45, 60, 75, 90 and 105 days), their biomass production, dry matter, chemical composition and in situ ruminal degradation kinetics of Morus alba, was evaluated in la María, Los Ríos, Ecuador. It was sampled in plots of 1,200 m2, in which a uniformity cut was applied at 0.5 m high over the soil level, without using irrigation or fertilization. Edible biomass, DMY, DM, CP, NDF, ADF and OM were determined, as well as in situ ruminal degradation kinetics (DM, NDF and OM). There were increases of dry matter and edible biomass production of 1.77 and 0.45 t/ha-1, respectively, as well as 7.5, 11.21 and 18.28 percent units for DM, NDF and ADF, while there was a decrease for CP and OM of 4.99 and 8.44 percent units, respectively up to 105 days. For degradation kinetics of dry matter, the best results were obtained at 30 days with 81.24%, 7.08%, 0.41%/h, 88.32%, 66.06%, 63.78%, and 61.51% for soluble fraction (a), potentially degradable (b), degradation rate (c), potential degradability (a+b) and effective degradability at ruminal passage rate of 2, 5 and 8 %, respectively. This same performance was maintained for OM and NDF. It can be concluded that regression equations were established, which explain the close relation among age, edible biomass production and dry matter. Dry matter and crude protein values were lower than those reported for this species in the international literature for production systems in tropical areas. These differences could be attributed to the zero use of irrigation and fertilization during the research. It is important to highlight that soluble fraction, potential and effective degradation of DM, OM and NDF were maintained with values superior to 50%. Further studies are suggested in other periods of the year, cut height, phytochemical composition, intake tests and animal response.

RESUMEN Mediante un diseño de bloques al azar y cuatro réplicas con seis tratamientos que consistieron en las edades de rebrote (30, 45, 60, 75, 90 y 105 días), se evaluó su efecto en la producción de biomasa, materia seca, composición química y cinética de la degradabilidad ruminal in situ de Morus alba, en la María, Los Ríos, Ecuador. Se muestreó en parcelas de 1200 m2, a la cual se aplicó el corte de uniformidad a 0.5 m de altura sobre el nivel del suelo y no se empleó riego ni fertilización. Se determinaron biomasa comestible, RMS, MS, PB, FDN, FDA y MO, así como la cinética degradación ruminal in situ (MS, FDN, MO). Hubo incrementos de la producción de biomasa comestible y materia seca de 1.77 y 0.45 t/ha-1, así como 7.5, 11.21 y 18.28 unidades porcentuales para la MS, FDN y FDA, mientras que para la PB y MO hubo disminución de 4.99 y 8.44 unidades porcentuales, respectivamente hasta los 105 días. Para la cinética de degradación de la materia seca los mejores resultados se obtuvieron a los 30 días con 81.24%, 7,08%, 0.41%/h, 88.32%, 66.06%, 63.78% y 61.51% para la fracción soluble (a), potencialmente degradable (b), tasa de degradación (c), degradabilidad potencial (a+b) y la efectiva a tasa de paso ruminal (2, 5 y 8%), respectivamente. Este mismo comportamiento se mantuvo para la MO y FDN. Se concluye que se establecieron ecuaciones de regresión que explican la estrecha relación que existe entre la edad, la producción de biomasa comestible y materia seca. Los valores de materia seca y proteína bruta están por debajo de los reportados para la especie en la literatura internacional para los sistemas de producción en el trópico, diferencias que pudieran ser atribuibles al no empleo de riego y fertilización durante la investigación. Vale destacar que la fracción soluble, degradación potencial y efectiva de la MS, MO y FDN se mantuvieron con valores superiores al 50%. Se sugiere realizar estudios en otros períodos del año, altura de corte, composición fitoquímica, pruebas de consumo y respuesta animal.

This paper presents the development of a computational model of the cochlea using a new solution by resonance analysis to the models of fluid mechanics in the cochlea and the basilar membrane as a system of forced harmonic oscillators proposed by Lesser and Berkeley. The computational model of resonance analysis is successfully compared with the method of numerical integration developed by Peterson and Bogert, the method of Green function proposed by Allen, the method of finite difference described by Neely and the measurements obtained in the experiments of Békésy, getting the same results with the new solution developed. Its contribution regarding the different solutions already found in the literature is to obtain a frequency-distance function to identify the maximum amplitude of displacement of each section along the basilar membrane for each specific excitation frequency in the hearing system. The model developed presents the advantage over the previous solutions, that the function obtained depends only of the physical characteristics of mass per unit area, damping coefficient and stiffness per unit area along the basilar membrane, and is the first time that the resonance analysis is used to obtain a methodology consistent with the place theory of hearing of Békésy.

En este trabajo de investigación se propone una nueva solución a partir del análisis por resonancia del modelo de mecánica de fluidos de la cóclea y su solución del comportamiento de la membrana basilar como un sistema de osciladores armónicos forzados propuesto por Lesser y Berkeley. El modelo computacional del análisis por resonancia se compara en forma satisfactoria con el método de integración numérica desarrollado por Peterson y Bogert, con el método de la función de Green propuesto por Allen, con el método de diferencias finitas propuesto por Neely y con las mediciones experimentales de Békésy, obteniendo los mismos resultados a partir de la nueva solución desarrollada. Su aportación respecto a las diferentes soluciones ya encontradas en la bibliografía, es obtener una relación frecuencia-distancia que permite identificar la distancia a la que ocurre la amplitud máxima de resonancia a lo largo de la membrana basilar para cada frecuencia específica de excitación al sistema auditivo. El modelo desarrollado tiene la ventaja de depender sólo de las características físicas a lo largo de la membrana basilar de: coeficiente de elasticidad, factor de amortiguamiento y masa por unidad de área; siendo la primera vez que se emplea el análisis por resonancia para obtener una metodología concordante en su totalidad con la teoría de los puntos de audición de Békésy.

Chronic necrotizing pulmonary aspergillosis is un uncommon disease which is found in people with underlying lung disease or in mildly immunocompromised patients. It is an exceptional complication in silicosis and its diagnosis is difficult because it simulates other diseases like tuberculosis and cancer which are more common in such patients. We report on three cases with a long history of silica dust exposure with pulmonary aspergillosis complicating progressive massive fibrosis (PMF). We review their clinical, radiological and treatment features.

La aspergilosis pulmonar necrotizante crónica es una rara enfermedad que tiende a afectar a personas con enfermedad pulmonar subyacente o inmunocomprometidos en grado leve. Es una complicación excepcional de la silicosis y su diagnóstico precisa un alto índice de sospecha pues simula otras enfermedades como tuberculosis y neoplasia, complicaciones más frecuentes en estos pacientes. Presentamos tres casos con larga historia de exposición a sílice y diagnóstico de fibrosis masiva progresiva que presentaron aspergilosis pulmonar. Revisamos sus características clínicas, radiológicas y tratamiento.

Male sex determination in humans is controlled by the SRY gene, which encodes a transcriptional regulator containing a conserved high mobility group box domain (HMG-box) required for DNA binding. Mutations in the SRY HMG-box affect protein function, causing sex reversal phenotypes. In the present study, we describe a 19-year-old female presenting 46,XY karyotype with hypogonadism and primary amenorrhea that led to the diagnosis of 46,XY complete gonadal dysgenesis. The novel p.E89K missense mutation in the SRY HMG-box was identified as a de novo mutation. Electrophoretic mobility shift assays showed that p.E89K almost completely abolished SRY DNA-binding activity, suggesting that it is the cause of SRY function impairment. In addition, we report the occurrence of the p.G95R mutation in a 46,XY female with complete gonadal dysgenesis. According to the three-dimensional structure of the human SRY HMG-box, the substitution of the conserved glutamic acid residue by the basic lysine at position 89 introduces an extra positive charge adjacent to and between the positively charged residues R86 and K92, important for stabilizing the HMG-box helix 2 with DNA. Thus, we propose that an electrostatic repulsion caused by the proximity of these positive charges could destabilize the tip of helix 2, abrogating DNA interaction.

Chronic myeloid leukemia (CML) is rare in the pediatric population, accounting for 2-3% of childhood leukemia cases, with an annual incidence of one case per million children. The low toxicity profile of imatinib mesylate has led to its approval as a front-line therapy in children for whom interferon treatment has failed or who have relapsed after allogeneic transplantation. We describe the positive responses of 2 children (case 1 - from a 7-year-old male since May 2005; case 2 - from a 5-year-old female since June 2006) with Philadelphia-positive chromosome CML treated with imatinib (300 mg/day, orally) for up to 28 months, as evaluated by morphological, cytogenetic, and molecular approaches. Our patients are alive, are in the chronic phase, and are in continuous morphological complete remission.

Os registros de 63.406 partos de vacas Siboney (5/8 Holstein 3/8 Cebu de Cuba) foram utilizados para estimar os componentes de (co)variância de dias vazios (DV). Utilizaram-se cinco modelos: de repetitividade; univariado; bivariado; de regressão aleatória com polinômios de Legendre e número de partos como variável preditiva; e de regressão aleatória com polinômios de Legendre e heterogeneidade da variância residual. A herdabilidade obtida com o modelo univariado foi de 0,09 no primeiro e diminuiu a 0,05 no quinto parto. Uma estimativa de herdabilidade mais alta (0,12) foi obtida com o modelo de repetitividade. Quando foi usado o modelo de regressão aleatória com heterogeneidade da variância residual a herdabilidade foi superior aos valores estimados com os modelos anteriores. As correlações genéticas entre os DV em distintos partos, estimadas com os modelos de regressão aleatória com e sem heterogeneidade da variância residual, foram próximos a 1,0. Concluiu-se que as estimativas de herdabilidade foram incrementadas com o uso dos modelos de regressão aleatória. As correlações genéticas entre os DV de diferentes partos indicaram que, nos três primeiros, os DV são regulados na sua maior proporção pelos mesmos genes.

The records of 63,406 calvings of Siboney dairy cows (5/8 Holstein 3/8 Cuban Zebu) were used to estimate the components of covariance of the days open (DO). Five models were used: of repeatability; univariate; bivariate; of random regression with Legendre polynomials and the parity number as predicting variable; and a model of random regression with Legendre polynomials and heterogeneity of the residual variance. The heritability obtained with the univariate model was 0.09 in the first calving and decreased to 0.05 in the fifth. A higher estimate of heritability (0.12) was obtained with the repeatability model. When the model of random regression with heterogeneity of the residual variance was used, the heritability was higher than the values estimated with the previous models. The genetic correlations among the DO in different calvings, estimated with the models of random regression with and without heterogeneity of the residual variance, were close to 1.0. It is concluded that the estimates of heritability increased with the use of the random regression models. The genetic correlations among the DO of different calvings indicated that in the first three, the DO are regulated for the most part by the same genes.

Nutritional substances associated to some hormones enhance liver regeneration when injected intraperitoneally, being denominated hepatotrophic factors (HF). Here we verified if a solution of HF (glucose, vitamins, salts, amino acids, glucagon, insulin, and triiodothyronine) can revert liver cirrhosis and how some extracellular matrices are affected. Cirrhosis was induced for 14 weeks in 45 female Wistar rats (200 mg) by intraperitoneal injections of thioacetamide (200 mg/kg). Twenty-five rats received intraperitoneal HF twice a day for 10 days (40 mL·kg-1·day-1) and 20 rats received physiological saline. Fifteen rats were used as control. The HF applied to cirrhotic rats significantly: a) reduced the relative mRNA expression of the genes: Col-α1 (-53%), TIMP-1 (-31.7%), TGF-β1 (-57.7%), and MMP-2 (-41.6%), whereas Plau mRNA remained unchanged; b) reduced GGT (-43.1%), ALT (-17.6%), and AST (-12.2%) serum levels; c) increased liver weight (11.3%), and reduced liver collagen (-37.1%), regenerative nodules size (-22.1%), and fibrous septum thickness. Progranulin protein (immunohistochemistry) and mRNA (in situ hybridization) were found in fibrous septa and areas of bile duct proliferation in cirrhotic livers. Concluding, HF improved the histology and serum biochemistry of liver cirrhosis, with an important reduction of interstitial collagen and increased extracelullar matrix degradation by reducing profibrotic gene expression.

Acquired defects of the upper third of the ear constitute a surgical challenge. Several techniques have been described, and results are sometimes unfavorable. An anatomical study in 10 fresh cadavers shows the constant presence of a neurovascular pedicle penetrating the root of helix. Location and vessel diameters are shown. Based on that anatomical knowledge, a series of 10 consecutive cases treated by the senior author is presented. Etiology, surgical technique, complications and long-term results are analyzed. The author's technique introduces a refinement of the Davis' technique, which uses a pedicled chondrocutaneous rotation conchal flap, cutaneous based on the upper auricular branch of superficial temporal artery. An axial pedicled superiorly based retroauricular flap provides the coverage of the new superior helical rim, and the posterior aspect of the chondrocutaneous flap is then covered with a full thickness skin graft. In a second stage, a Z plasty on the root of helix brings it a natural shape All the anatomical dissections demonstrate the presence of a neurovascular pedicle penetrating the root of the helix. The clinical series is composed by 8 traumatic defects, 1 electrical burn and 1 benign skin tumor. All flaps survived and so demonstrated pedicle safety. Two retroauricular flaps presented vascular deficit, one of them with complete spontaneous restoration and the other one with small distal cutaneous necrosis. Two cases suffered partial skin graft loss. Some technical details were developed while the series went on, which are discussed. All 9 patients recovered auricular contour, which seems better for us using the above described refinements. As a conclusion, the Davis's technique represents an effective method to reconstruct the upper pole of the ear. Some technical refinements can improve the results with this approach, achieving a more natural contour of the reconstructed area.

Los defectos del tercio superior auricular son un desafío reconstructivo. Están descritas diferentes técnicas quirúrgicas para este fin con resultados a veces desfavorables Realizamos un estudio anatómico en cadáveres frescos que mostró la presencia constante de un pedículo neurovascular que penetra la raíz del hélix. Mostramos la localización y los diámetros de los vasos. Basándonos en este estudio anatómico, presentamos una serie de 10 casos consecutivos tratados por el autor principal. Analizamos la etiología, técnica quirúrgica, complicaciones y resultado a largo plazo. La técnica del autor introduce refinamientos a la técnica de Davis, el cual usa un colgajo condrocutáneo de concha auricular basado en la rama superior de la arteria temporal superficial y un colgajo cutáneo axial de base superior basado en la arteria retroauricular, para crear el nuevo hélix auricular superior. El aspecto posterior de este colgajo condrocutáneo se cubre con un injerto de piel total. En un segundo tiempo empleamos una zetaplastia de la base del hélix que nos dará una mejor forma. El estudio anatómico demostró la presencia de un pedículo neurovascular que penetra la raíz del hélix. La serie clínica está compuesta por 8 defectos postraumáticos, una quemadura eléctrica y un tumor de piel. Todos los colgajos condrocutáneos de concha auricular sobrevivieron comprobándose la seguridad del pedículo del hélix. Dos colgajos retroauriculares presentaron sufrimiento vascular transitorio distal, uno de ellos con recuperación completa y otro con necrosis distal mínima. Dos casos sufrieron pérdida parcial del injerto de piel total. Durante el desarrollo de la serie descubrimos algunos detalles de la técnica quirúrgica, que ahora discutimos en el artículo. Todos los pacientes recuperaron el contorno auricular, obteniendo los mejores resultados en aquellos en los que se aplicaron los refinamientos descritos. En conclusión, creemos que la técnica de Davis representa un efectivo método de reconstrucción del tercio superior auricular; los refinamientos a la técnica que comunicamos mejoran los resultados, dando un contorno más natural al área reconstruida.

The buccinator myomucosal flap (BMF) constitutes a valid alternative for the reconstruction of moderate defects of the oral cavity. It is characterized by a good pliability, excellent color and texture and minimum donor site morbidity. In this report, the anatomical particularities and the different surgical techniques for BMF are described. Its use in patients with different defects of the oral cavity illustrates its versatility. We present 4 cases of reconstruction of defects of the maxillofacial area: two cases consisting in squamous cell carcinoma of the floor of the mouth, another patient with melanoma of the oral mucosa and one patient with a palatine fissure. All of them underwent primary reconstruction by means of BMF. Good results were obtained in relation to covering of the defect, aesthetics and function. Morbidity was minimal in the donor site. Due to its anatomical features, an adequate surgical technique must be performed. Proximity of the BMF to the vast majority of defects of the oral cavity, and its acceptable thickness, show the flap to be a reliable reconstructive procedure. This is especially valid in those patients where the size of the defect and the existence of comorbidity advise against the use of other flaps.

El colgajo miomucoso de buccinador (CMB) constituye una alternativa válida para la reconstrucción de defectos intraorales de tamaño moderado. Se caracteriza por su buena plegabilidad, excelente color y textura, además de una mínima morbilidad de la zona donante. En el presente trabajo se describen las particularidades anatómicas de dicho colgajo, así como las diferentes técnicas quirúrgicas que pueden emplearse para su obtención. Su utilización en diferentes defectos de la cavidad oral, ilustra la versatilidad del mismo. Presentamos 4 casos de reconstrucción de defectos del área maxilofacial: dos pacientes con carcinoma epidermoide de suelo de boca, un paciente con melanoma de mucosa y un paciente con fisura palatina. Se obtuvieron resultados óptimos en cuanto a cobertura del defecto postquirúrgico, estética y función. En todos los casos la morbilidad de la zona donante fue mínima. Dadas sus particularidades anatómicas, debe realizarse una cuidadosa técnica de obtención del mismo. La proximidad del CMB a la gran mayoría de los defectos de la cavidad oral y su aceptable espesor, hace del mismo una opción reconstructiva eficaz, sobre todo en aquellos pacientes en los que el tamaño del defecto y/o la existencia de patología asociada desaconsejan el uso de otros colgajos.

Renal involvement in visceral leishmaniasis (VL) is very frequent. The renal lesions of humans and dogs are similar but their pathogenesis has not been clearly elucidated. There is growing evidence that the cellular immune response is involved in the pathogenesis of immunologically mediated glomerulonephritis. Since T cells could participate in the pathogenesis of nephropathy, in the present study we investigated the possible involvement of CD4+ and CD8+ T cells in the nephropathy of canine VL. Six dogs naturally infected with Leishmania (Leishmania) chagasi from the endemic area in the Northeast of Brazil, the town of Teresina in the State of Piauí, were studied. An expressive inflammatory infiltrate of CD4+ T cells both in glomeruli and in interstitium was present in 4 animals and absent in 2. CD8+ T cells were detected only in one animal. CD4+ T cells alone were observed in 3 animals; when CD8+ T cells were present CD4+ T cells were also present. CD4+ T cells were observed in cases of focal segmental glomerulosclerosis, diffuse membranoproliferative glomerulonephritis, diffuse mesangial proliferative glomerulonephritis and crescentic glomerulonephritis. CD8+ T cells were present only in a case of crescentic glomerulonephritis. Leishmania antigen was detected in glomeruli and in interstitial inflammatory infiltrate in 4 animals and immunoglobulins were observed in 4 dogs. In this study we observed that T cells, in addition to immunoglobulins, are present in the renal lesion of canine VL. Further studies are in progress addressing the immunopathogenic mechanisms involving the participation of immunoglobulins and T cells in canine VL nephropathy.

The in utero exposure of hamsters to low doses of diazepam results in impaired host defense against Mycobacterium bovis during adulthood. Delayed developmental immunotoxicity, however, represents a specific situation that might not be general. The present experiment was undertaken to investigate the effects of diazepam on hamster resistance to M. bovis using adult animals. The effects of diazepam treatment on serum cortisol levels were also studied. Adult hamsters (N = 10 for each group) were treated with diazepam (E1 = 1.0, E2 = 2.0 or E3 = 3.0 mg kg-1 day-1 subcutaneously) or with control solution (C) for 30 days. Seven days after the beginning of the treatment, the animals received identical inoculum concentrations of M. bovis. Hamsters treated with the higher (2.0 and 3.0 mg kg-1 day-1) doses of diazepam exhibited: 1) increased granuloma areas in the liver (C = 1.81 ± 1.39, E2 = 10.29 ± 4.64 and E3 = 15.80 ± 4.82) and lung (C = 0.54 ± 0.55, E2 = 6.28 ± 3.85 and E3 = 6.31 ± 3.56) and 2) increased scores of M. bovis colony-forming units isolated from liver (C = 2.0, E2 = 3.0 and E3 = 3.5), lung (C = 1.0, E2 = 3.0 and E3 = 3.5) and spleen (C = 1.0, E2 = 2.5 and E3 = 4.0). These effects were dose dependent, and were not detected or were less severe in animals treated with the lowest (1.0 mg/kg) dose of diazepam as well as in those of the control group. Furthermore, diazepam treatment (3.0 mg kg-1 day-1 for 30 days) increased (E3 = 71.32 ± 2.99; N = 10) the serum levels of cortisol compared to control hamsters (C = 22.61 ± 2.75; N = 10). The present data, that demonstrate an impaired defense against M. bovis in adult hamsters treated with diazepam, were tentatively explained on the basis of a direct and/or indirect action of diazepam on the cytokine network. The effects may be related to stimulation of peripheral benzodiazepine receptor binding sites (PBR) by macrophages and/or lymphocytes, or they may be mediated by PBR stimulation of the adrenals.