Cytoarchitecture of the medial nucleus of trapezoid body of three neotropical species of bats (Noctilio leporinus, Phyllostomus hastatus, and Carollia perspicillata) with different foraging behavior / Citoarquitetura do núcleo medial do corpo trapezoidal de três espécies neotropicais de morcegos (Noctilio leporinus, Phyllostomus hastatus e Carollia perspicillata) com diferentes comportamentos de forrageamento

Abstract The present study was taken to test the hypothesis that the medial nucleus of the trapezoid body (MNTB) of echolocating neotropical bats with different foraging behavior will exhibit morphological variations in relative size, degree of complexity and spatial distribution. The brains were collected from six male adult bats of each species: Noctilio leporinus (fish-eating), Phyllostomus hastatus (carnivorous/ omnivorous) and Carollia perspicillata (fruit-eating) and were double-embedded and transverse serial sections were cut and stained with cresyl fast violet. The results showed that the MNTB is well developed in all the bats in general and the mean length of the MNTB was 1160 ± 124 µm in N. leporinus, 400 ± 59 µm in P. hastatus and 320 ± 25µm in C. perspicillata. The body and brain weight do not reflect proportionately on the size of the MNTB in the present study. The hearing frequency spectrum did not covary with the size of the MNTB among the bats studied. The MNTB is clearly demarcated from the ventral nucleus of the trapezoid body (VNTB) only in P. hastatus. The MNTB comprised mainly three types of cells in all three bats: dense-staining multipolar cells (12.5 µm and 25.0 µm diameter); light-staining multipolar cells measuring (12.5 µm and 25.0 µm diameter) and light-staining round cells (5.0 µm diameter). The large sized MNTB was observed in N. leporinus, which suggests that it relies heavily on echolocation whereas P. hastatus and C. perspicillata use echolocation as well but also rely on hearing, smell and vision.

Resumo O presente estudo foi realizado para testar a hipótese de que o núcleo medial do corpo trapezoide (MNTB) de morcegos neotropicais ecolocativos com comportamento forrageiro diferente apresenta variações morfológicas no tamanho relativo, grau de complexidade e distribuição espacial. Os cérebros foram coletados de seis morcegos machos adultos de cada espécie, Noctilio leporinus (comedor de peixe), Phyllostomus hastatus (carnívoro/onívoro) e Carollia perspicillata (comedor de frutas), e foram seccionados em série e seções seriais transversais duplas e coradas com cresil violeta. Os resultados mostraram que o MNTB é bem desenvolvido em todos os morcegos em geral e que o comprimento médio do MNTB foi de 1.160 ± 124 µm em N. leporinus, 400 ± 59 µm em P. hastatus e 320 ± 25 µm em C. perspicillata. O peso corporal e cerebral não reflete proporcionalmente o tamanho do MNTB no presente estudo. O espectro da frequência auditiva não covaria com o tamanho do MNTB entre os morcegos estudados. O MNTB é claramente demarcado do núcleo ventral do corpo trapezoidal (VNTB) apenas em P. hastatus. O MNTB compreendia principalmente três tipos de células nos três morcegos: células multipolares de coloração densa (12,5 µm e 25,0 µm de diâmetro), células multipolares de coloração clara (12,5 µm e 25,0 µm de diâmetro) e células redondas manchadas de luz (5,0 µm de diâmetro). O MNTB de grande porte foi observado em N. leporinus, o que sugere que ele depende muito da ecolocalização, enquanto P. hastatus e C. perspicillata também usam a ecolocalização, mas dependem da audição, olfato e visão.

Cytoarchitecture of the superior olivary complex of three neotropical species of bats (Noctilio leporinus, Phyllostomus hastatus and Carollia perspicillata) with different foraging behavior / Citoarquitetura do complexo olivar superior de três espécies neotropicais de morcegos (Noctilio leporinus, Phyllostomus hastatus e Carollia perspicillata) com diferentes comportamentos de forrageamento

Abstract The understanding of the echolocation by studying different auditory nuclei of echolocating bats can be an important link in elucidating questions arising in relation to their foraging behavior. The superior olivary complex (SOC) is the primary center for processing the binaural cues used in sound localization since echo locating bats rely on acoustic cues to navigate and capture prey while in flight. The present study was taken to test the hypothesis that the SOC of echolocating neotropical bats with different foraging behavior will exhibit morphological variations in relative size, degree of complexity and spatial distribution. The brains were collected from six male adult bats of each species: Noctilio leporinus (fish eating), Phyllostomus hastatus (carnivorous/omnivorous) and Carollia perspicillata (fruit eating). They were double-embedded and transverse serial sections were cut and stained with cresyl fast violet. The SOC measured as 640 ± 70 µm in the N. leporinus bat, 480 ± 50 µm in the P. hastatus and 240 ± 30 µm in the C. perspicillata bat. The principal nuclei of the SOC of in all three bats were the LSO, MSO and MNTB. The MSO and LSO were very well developed in N. leporinus bats. The MSO of N. leporinus bat subdivided into DMSO and VMSO. The main cell type of cells present in MSO and LSO are dark staining multipolar cells in all the bats studied. The well-developed MSO and LSO of N. leporinus bats indicate that these bats are highly sensitive to low frequency sounds and interaural intensity differences, which help these bats to forage over water by using various types of echolocation signals. The average size of SOC in P. hastatus and C. perspicillata bats can be attributed to the fact that these bats use vision and smell along with echolocation to forage the food.

Resumo O entendimento da ecolocalização pelo estudo de diferentes núcleos auditivos de morcegos pode ser um elo importante na elucidação das inúmeras questões que surgem em relação ao seu comportamento de forrageamento. O complexo olivar superior (SOC) é o principal centro de processamento das pistas binaurais usadas na localização do som, já que os morcegos ecolocalizadores contam com sinais acústicos para navegar e capturar as presas durante o vôo. O presente estudo foi realizado para testar a hipótese de que morcegos que usam a ecolocalização para diferentes comportamentos de forrageamento irão variar na estrutura, tamanhos relativos e grau de complexidade e distribuição espacial do grupo SOC. Os cérebros foram coletados de seis machos adultos de morcego de cada espécie: Noctilio leporinus (piscívoro), Phyllostomus hastatus (carnívoros/onívoros) e Carollia perspicillata (frugívoro). Eles foram seccionados em série e transversalmente, cortados e corados com coloração rápida cresil-violeta. tolet. O grupo SOC foi medido como 640 ± 70 µm no morcego N. leporinus, 480 ± 50 µm no P. hastatus e 240 ± 30 µm no morcego C. perspicillata. Os principais núcleos do grupo SOC dos três morcegos foram o LSO e o MSO e o MNTB. O MSO e o LSO foram muito bem desenvolvidos em morcegos N. leporinus. A MSO de N. leporinus foi subdividida em DMSO e VMSO. O principal tipo de células presentes na MSO e LSO são as células multipolares de coloração escura em todos os morcegos. Os MSO bem desenvolvidos e LSO de morcegos N. leporinus indicam que estes morcegos são altamente sensíveis a sons de baixa frequência e diferenças de intensidade interaural, que ajudaram estes morcegos a se alimentarem na superfície da água usando vários tipos de sinais de ecolocalização. O tamanho médio de SOC em morcegos de P. hastatus e C. perspicillata pode ser atribuído ao fato destes morcegos usarem visão e olfato junto com a ecolocalização para forragear.

Cytoarchitecture of the superior olivary complex of three neotropical species of bats (Noctilio leporinus, Phyllostomus hastatus and Carollia perspicillata) with different foraging behavior

Abstract The understanding of the echolocation by studying different auditory nuclei of echolocating bats can be an important link in elucidating questions arising in relation to their foraging behavior. The superior olivary complex (SOC) is the primary center for processing the binaural cues used in sound localization since echo locating bats rely on acoustic cues to navigate and capture prey while in flight. The present study was taken to test the hypothesis that the SOC of echolocating neotropical bats with different foraging behavior will exhibit morphological variations in relative size, degree of complexity and spatial distribution. The brains were collected from six male adult bats of each species: Noctilio leporinus (fish eating), Phyllostomus hastatus (carnivorous/omnivorous) and Carollia perspicillata (fruit eating). They were double-embedded and transverse serial sections were cut and stained with cresyl fast violet. The SOC measured as 640 ± 70 µm in the N. leporinus bat, 480 ± 50 µm in the P. hastatus and 240 ± 30 µm in the C. perspicillata bat. The principal nuclei of the SOC of in all three bats were the LSO, MSO and MNTB. The MSO and LSO were very well developed in N. leporinus bats. The MSO of N. leporinus bat subdivided into DMSO and VMSO. The main cell type of cells present in MSO and LSO are dark staining multipolar cells in all the bats studied. The well-developed MSO and LSO of N. leporinus bats indicate that these bats are highly sensitive to low frequency sounds and interaural intensity differences, which help these bats to forage over water by using various types of echolocation signals. The average size of SOC in P. hastatus and C. perspicillata bats can be attributed to the fact that these bats use vision and smell along with echolocation to forage the food.

Resumo O entendimento da ecolocalização pelo estudo de diferentes núcleos auditivos de morcegos pode ser um elo importante na elucidação das inúmeras questões que surgem em relação ao seu comportamento de forrageamento. O complexo olivar superior (SOC) é o principal centro de processamento das pistas binaurais usadas na localização do som, já que os morcegos ecolocalizadores contam com sinais acústicos para navegar e capturar as presas durante o vôo. O presente estudo foi realizado para testar a hipótese de que morcegos que usam a ecolocalização para diferentes comportamentos de forrageamento irão variar na estrutura, tamanhos relativos e grau de complexidade e distribuição espacial do grupo SOC. Os cérebros foram coletados de seis machos adultos de morcego de cada espécie: Noctilio leporinus (piscívoro), Phyllostomus hastatus (carnívoros/onívoros) e Carollia perspicillata (frugívoro). Eles foram seccionados em série e transversalmente, cortados e corados com coloração rápida cresil-violeta. tolet. O grupo SOC foi medido como 640 ± 70 µm no morcego N. leporinus, 480 ± 50 µm no P. hastatus e 240 ± 30 µm no morcego C. perspicillata. Os principais núcleos do grupo SOC dos três morcegos foram o LSO e o MSO e o MNTB. O MSO e o LSO foram muito bem desenvolvidos em morcegos N. leporinus. A MSO de N. leporinus foi subdividida em DMSO e VMSO. O principal tipo de células presentes na MSO e LSO são as células multipolares de coloração escura em todos os morcegos. Os MSO bem desenvolvidos e LSO de morcegos N. leporinus indicam que estes morcegos são altamente sensíveis a sons de baixa frequência e diferenças de intensidade interaural, que ajudaram estes morcegos a se alimentarem na superfície da água usando vários tipos de sinais de ecolocalização. O tamanho médio de SOC em morcegos de P. hastatus e C. perspicillata pode ser atribuído ao fato destes morcegos usarem visão e olfato junto com a ecolocalização para forragear.

Cytoarchitecture of the medial nucleus of trapezoid body of three neotropical species of bats (Noctilio leporinus, Phyllostomus hastatus, and Carollia perspicillata) with different foraging behavior

Abstract The present study was taken to test the hypothesis that the medial nucleus of the trapezoid body (MNTB) of echolocating neotropical bats with different foraging behavior will exhibit morphological variations in relative size, degree of complexity and spatial distribution. The brains were collected from six male adult bats of each species: Noctilio leporinus (fish-eating), Phyllostomus hastatus (carnivorous/ omnivorous) and Carollia perspicillata (fruit-eating) and were double-embedded and transverse serial sections were cut and stained with cresyl fast violet. The results showed that the MNTB is well developed in all the bats in general and the mean length of the MNTB was 1160 ± 124 µm in N. leporinus, 400 ± 59 µm in P. hastatus and 320 ± 25µm in C. perspicillata. The body and brain weight do not reflect proportionately on the size of the MNTB in the present study. The hearing frequency spectrum did not covary with the size of the MNTB among the bats studied. The MNTB is clearly demarcated from the ventral nucleus of the trapezoid body (VNTB) only in P. hastatus. The MNTB comprised mainly three types of cells in all three bats: dense-staining multipolar cells (12.5 µm and 25.0 µm diameter); light-staining multipolar cells measuring (12.5 µm and 25.0 µm diameter) and light-staining round cells (5.0 µm diameter). The large sized MNTB was observed in N. leporinus, which suggests that it relies heavily on echolocation whereas P. hastatus and C. perspicillata use echolocation as well but also rely on hearing, smell and vision.

Resumo O presente estudo foi realizado para testar a hipótese de que o núcleo medial do corpo trapezoide (MNTB) de morcegos neotropicais ecolocativos com comportamento forrageiro diferente apresenta variações morfológicas no tamanho relativo, grau de complexidade e distribuição espacial. Os cérebros foram coletados de seis morcegos machos adultos de cada espécie, Noctilio leporinus (comedor de peixe), Phyllostomus hastatus (carnívoro/onívoro) e Carollia perspicillata (comedor de frutas), e foram seccionados em série e seções seriais transversais duplas e coradas com cresil violeta. Os resultados mostraram que o MNTB é bem desenvolvido em todos os morcegos em geral e que o comprimento médio do MNTB foi de 1.160 ± 124 µm em N. leporinus, 400 ± 59 µm em P. hastatus e 320 ± 25 µm em C. perspicillata. O peso corporal e cerebral não reflete proporcionalmente o tamanho do MNTB no presente estudo. O espectro da frequência auditiva não covaria com o tamanho do MNTB entre os morcegos estudados. O MNTB é claramente demarcado do núcleo ventral do corpo trapezoidal (VNTB) apenas em P. hastatus. O MNTB compreendia principalmente três tipos de células nos três morcegos: células multipolares de coloração densa (12,5 µm e 25,0 µm de diâmetro), células multipolares de coloração clara (12,5 µm e 25,0 µm de diâmetro) e células redondas manchadas de luz (5,0 µm de diâmetro). O MNTB de grande porte foi observado em N. leporinus, o que sugere que ele depende muito da ecolocalização, enquanto P. hastatus e C. perspicillata também usam a ecolocalização, mas dependem da audição, olfato e visão.

Elevated ferric, calcium and magnesium ions in the brain induce protein aggregation in brain mitochondria / El aumento de iones férricos, calcio y magnesio en el cerebro induce la agregación de proteínas en las mitocondrias del cerebro

OBJECTIVE: Alzheimer s disease and Parkinson s disease are two of several neurodegenerative disorders that affect the elderly. Although their aetiology remains uncertain, studies suggest that elevated aluminium or other metal ions in the brain directly influence the development of the histological abnormalities normally associated with these diseases; other investigations suggest that metal-ion-induced-dysfunction of mitochondria might be a critical factor. METHODS: In this study, the impact of elevated aluminum (Al3+), ferric (Fe3+), calcium (Ca2+) and magnesium (Mg2+) ions on brain histology and on the protein composition of brain mitochondria were evaluated. Rabbits were injected intra-cerebrally with 1.4% solutions of either aluminium chloride (AlCl3), ferric chloride (FeCl2), calcium chloride (CaCl2) or magnesium chloride (MgCl2) and sacrificed 10 days later. RESULTS: Histological analysis revealed that Al3+ but not the other ions induced neurofibrillary degeneration within the midbrain and medulla. Alternatively, SDS-PAGE revealed that Fe3+, Ca2+ and Mg2+ but not Al3+ induced alterations to the distribution of brain mitochondrial proteins. Both Fe3+ and Ca2+ triggered decreased concentration of three low molecular weight proteins (~7-14 kd) but Ca precipitated their total absence. Both ions led to increased concentration of a high molecular weight protein (~ 110 kd). In contrast, Mg2+ led to the total absence of the protein of lowest molecular weight (~7 kd) and increased concentration of a ~36 kd protein. CONCLUSION: These results suggest that elevation of some metal ions in the brain induces protein aggregation with the nature of the aggregation being highly ion dependent. The results also point toward major differences between the histopathological effect of Al3+ and other ions.

OBJETIVO: La enfermedad de Alzheimer y la enfermedad de Parkinson son dos de los varios trastornos neurodegenerativos que afectan al anciano. Aunque su etiologia sigue siendo incierta, los estudios sugieren que el aumento de los iones de aluminio, influyen directamente sobre el desarrollo de las anormalidades histológicas asociadas normalmente con estas enfermedades. Otras investigaciones sugieren que la disfunción de las mitocondrias, inducida por iones metálicos, pudiera ser un factor critico. MÉTODOS: Este estudio evalúa el impacto del aumento de los iones de aluminio (Al3+), los iones férricos (Fe3+), y los iones de calcio (Ca2+) y magnesio (Mg2+) sobre la histologia del cerebro y la composición proteica de las mitocondrias del cerebro. Un número de conejos recibieron inyecciones intracerebrales de soluciones al 1.4% de soluciones de cloruro de aluminio (AlCl3), cloruro ferroso (FeCl3), cloruro de calcio (CaCl2), o cloruro de magnesio (MgCl2), y fueron sacrificados después de 10 días. RESULTADOS: El análisis histológico reveló que el Al3+ indujo una degeneración neurofibrilar dentro del mesencéfalo y la médula, Sin embargo, esto no ocurrió con los otros iones. Alternativamente, la técnica de electroforesis SDS-PAGE reveló que los iones Fe3+, Ca2+ y Mg2+, a diferencia del ión Al3+, inducían alteraciones de la distribución de las proteínas mitocondriales cerebrales. Tanto el Fe3+ como el Ca2+ desencadenaron una disminución de la concentración de tres proteínas de bajo peso molecular (~7-14 kd) pero Ca2+ precipitó su ausencia total. Ambos iones condujeron a un aumento de una proteína de peso molecular alto (~ 110 kd). En cambio, Mg2+ llevó a la ausencia total de la proteína de más bajo peso molecular (~7 kd) y al aumento de la concentración de una proteína de ~36 kd. CONCLUSIÓN: Estos resultados parecen sugerir que la elevación de algunos iones de metal en el cerebro induce la agregación de la proteína, siendo la naturaleza de la agregación altamente dependiente de los iones. Los resultados también apuntan a grandes diferencias entre el efecto histopatológico del Al3+ y otros iones.

The effects of ingested aluminium on brain cytochrome oxidase activity / Efectos de la ingestión de aluminio sobre la actividad de la oxidasa citocrómica del cerebro

Aluminium has a unique combination of physical and chemical properties which has enabled man to put this metal to very wide and varied use. However, prolonged exposure to aluminium ions may lead to adverse health effects. In this study, we evaluated the effects of dietary aluminium on the protein composition and the intrinsic activity of cytochrome oxidase (COX) for brain mitochondria. New Zealand white rabbits were maintained on a diet of commercial rabbit pellets and distilled water for a period of 12 weeks. For the experimental group, AlCl3, 330mg/kg/L was added to the drinking water. When compared to the control, mitochondria isolated from the brains of the AlCl3 fed rabbits showed no change in Km but an approximate 35% decrease in both the low and high affinity Vmax values. Also, whereas the protein composition of the mitochondria from both sources appeared to be normal, isolation of highly purified COX proved to be difficult and for the AICI3 fed rabbits, a number of the enzyme's low molecular weight subunits were absent. These results appear to confirm a relationship between long term aluminium consumption and low brain COX activity; they further suggest that an altered COX structure may be the cause of the low enzymic activity.

El aluminio posee una combinación única de las propiedades físicas y químicas que ha permitido al ser humano hacer un uso amplio y variado de este metal. Sin embargo, un número de estudios recientes, sugiere que la exposición prolongada a los iones de aluminio puede tener efectos nocivos sobre la salud. En el presente estudio, evaluamos los efectos del aluminio dietético sobre la composición proteínica y la actividad intrínseca de la oxidasa citocrómica (COX) para la mitocondria cerebral. Conejos blancos de Nueva Zelanda, fueron mantenidos con una dieta de alimento para conejos y agua destilada por un período de 12 semanas. Para el grupo experimental AlCl3, 330mg/kg/L fueron añadidos al agua potable. En comparación con el grupo de control, las mitocondrias aisladas de los cerebros de los conejos alimentados con AlCl3 no mostraron cambios en Km pero hubo una disminución de aproximadamente 35% tanto en los valores Vmax de baja y alta afinidad. Por otro lado, mientras que la composición proteica de las mitocondrias de ambas fuentes parecía ser normal, resultó difícil aislar el COX altamente purificado y un número de enzimas de subunidades de bajo peso molecular MMMM estuvieron ausentes. Estos resultados parecen confirmar una relación entre el consumo de aluminio a largo plazo y la baja actividad del COX del cerebro. Asimismo, sugieren que una alteración de la estructura del COX puede ser la causa de una baja actividad enzimática.

Single photon emission computerized tomography in the evaluation of the osteoblastic activities of a new bone regeneration technique: analysis of 12 mandibular sites in six experimental pigs / La tomografía computarizada por emisión de fotón único en la evaluación de las actividades osteoblásticas de una nueva técnica de regeneración ósea: análisis de 12 sitios mandibulares en seis cerdos experimentales

OBJECTIVES: To utilize single photon emission computerized tomography performed in sequence to determine the osseo-integrating capabilities and osteoblastic activities of a new bone regeneration technique called the membrane - sandwich technique (Ogunsalu sandwich bone regenerating technique) and to compare the quality and quantity of bone formed by this bone regeneration unit to bone regeneration obtained by using the same particulate bone grafting material covered with interceed® (another type of bio-resorbable membrane). DESIGN AND METHOD: Single photon emission computerized tomography bone imaging was performed in sequence on the mandible of a total of 6 pigs on both the right and left side (total of 12 sites) at two and a half hours following the injection of technetium 99m methylene diphosphate. Imaging was performed using a Siemen Orbitar II gamma camera. The projection data was acquired in a 128 x 128 matrix over 180 arc and SPECT reconstruction was performed using a filtered back projector method with a Shepp-Logan Hanning filter and a cut-off frequency of 0.4. The surgical defect on one side of the jaw was treated with the sandwich unit with Bio-oss particulate bone within it, while the other side contained the same quantity of Bio-oss as in the left side but just covered with interceed® membrane. The osteoblastic uptake on the side with the classical sandwich was compared to the side with the particulate bone covered with interceed® membrane for dynamic physiological activities. The average activity for both sides was calculated and compared. RESULT: For all the 12 sites, osteoblastic activities were recorded and indicated that vascularized bone was formed at all the experimental sites. Autogenous bone graft was confirmed to be superior to xenograft using this sandwich technique. Furthermore, the osteoblastic activities on the sandwich side were seen to be more when compared with the control side (Interceed® side). CONCLUSION: The Ogunsalu sandwich bone regeneration technique has been successfully evaluated with SPECT which shows osteoblastic activity with formation of vascularized bone which integrates with the surrounding bone.

OBJETIVOS: Utilizar la tomografía computarizada por emisión de fotón único (TCEFU) realizada en secuencia, a fin de determinar la capacidad óseo-integradora y las actividades osteoblásticas de una nueva técnica de regeneración del hueso, denominada técnica de membrana-sándwich, y comparar la calidad y cantidad de hueso formado por esta unidad de regeneración ósea con la regeneración ósea obtenida mediante el mismo material de injerto de hueso particulado cubierto con interceed® (otro tipo de membrana bioreabsorbible). DISEÑO Y MÉTODO: Mediante TCEFU, se realizó un estudio de imágenes óseas en secuencia, de la mandíbula de un total de 6 cerdos, a los lados izquierdo y derecho (un total de 12 sitios) a las dos horas y media, luego de una inyección de difosfato de metileno marcado con tecnecio 99 m. El examen de imágenes fue realizado usando una cámara gamma Siemens Orbiter tipo II. Los datos de la proyección fueron adquiridos en una matriz de 128 x 128 sobre un arco de 180 y la reconstrucción con TCEFU se realizó usando un método de retroproyección filtrada, con un filtro Shepp-Logan-Hanning y una frecuencia de corte de 0.4. El defecto quirúrgico en un lado de la mandíbula fue tratado con la unidad de sándwich con hueso particulado bio-oss dentro, mientras que el otro lado contenía la misma cantidad de Bio-oss del lado izquierdo, pero cubierto con una membrana de interceed®. La respuesta osteoblástica en el lado con el sándwich clásico fue comparada con el lado del hueso particulado cubierto con la membrana de interceed® en cuanto a actividades fisiológicas dinámicas. La actividad promedio de ambos lados fue calculada y comparada. RESULTADO: En los 12 sitios, las actividades osteoblásticas fueron registradas de forma indicando que se formó hueso vascularizado en todos los sitios experimentales. Se confirmó que el injerto óseo autógeno es superior al xenoinjerto que usa esta técnica de sándwich. Además, se observó que las actividades osteoblásticas en el lado del sándwich eran más en comparación con el lado control (lado del interceed®). CONCLUSIÓN: La técnica de Ogunsalu para la regeneración ósea por "sándwich" o membrana inter-posicional, ha sido exitosamente evaluada mediante TCEFU, concluyéndose que la misma consiste en la actividad osteoblástica con formación de hueso vascularizado que se integra al hueso circundante.

Single photon emission computerized tomography and histological evaluation in the validation of a new technique for closure of oro-antral communication: an experimental study in pigs / Tomografía computarizada mediante emisión de fotones simples y evaluación histológica en la validación de una nueva técnica para el cierre de la comunicación oroantral: un estudio experimental en cerdos

Various bone regeneration techniques have evolved recently but controversies regarding vascularization and integration of such bone grafting techniques have led occasionally to animal experiment to validate such techniques. The objective of this study was to evaluate the evidence of vascularization and osseo-integration of a new bone regeneration technique utilized for the closure of oro-antral communication (OAC) by an experimental model in which Single Photon Emission computerized Tomography and histological studies were conducted in pigs. We conclude that the sandwich technique used for the closure of OAC results in a vascularized new bone formation which eventually osseo-integrate with the surrounding bone. Also, this experimental study confirmed that autogeneous bone graft was superior to xenografts when used within the sandwich unit.

Varias técnicas de regeneración de huesos han sido desarrolladas recientemente, pero las controversias con respecto a la vascularización e integración de tales técnicas de injerto de hueso han llevado de vez en cuando a la experimentación con animales, a fin de validar estas técnicas. El objetivo de este estudio fue evaluar la evidencia de vascularización e integración ósea de una nueva técnica de regeneración de hueso utilizada para el cierre de la comunicación oro-antral (COA), mediante un modelo experimental en el que se practicó la tomografía computarizada mediante emisión de fotones simples y se realizaron estudios histológicos en cerdos. Concluimos que la técnica de sándwich usada para el cierre de COA da lugar a una formación ósea vascularizada que acaba produciendo una oseointegración con el hueso circundante. Asimismo, este estudio experimental confirmó que el injerto óseo antólogo es superior a los xenoinjertos cuando se usa dentro de la unidad de sándwich.

Marginally low copper causes lesions of the midbrain in animal models: the implications for man

Serum copper levels must be maintained between very strict limits for the maintenance of good health. High levels have recently been linked to Alzheimer's disease while low levels during pregnancy cause enzootic ataxia (swayback disease) in offspring. In this study, we investigated the prolonged effect of serum copper that was maintained at and around 0.5 ppm, the level presently regarded as safe. Pregnant sheep and rabbits in the last trimester (1-4 weeks) of pregnancy were treated with the copper chelator ammonium tetrathiomolybdate (ATM). Treatment was continued until the young were one month old at which time the animals were sacrificed Serum copper levels of the parents and offspring were monitored by atomic absorption. The difference spectra (400-630 nm) was examined and SDS PAGE was used to evaluate the protein composition of the brain mitochondria. The anatomy of the midbrain was also studied. Although the young sheep and rabbits from the ATM-treated mothers showed no visible signs of disability or swayback disease, the midbrain of those young animals with serum copper between 0.3-0.9 ppm showed evidence of vacuolation, cavitation and chromatolysis. In contrast, the difference spectra and the protein composition of the brain mitochondria from these animals were all normal. These results suggest that although animals may appear normal and exhibit some normal biochemical markers, serum copper in the region of 0.5 ppm may not be safe for some breeds of sheep or rabbits. It is possible that a similar situation applies to man.

Los niveles séricos cúpricos tienen que ser mantenidos dentro de límites muy estrictos, si se quiere tener una buena salud. Los altos niveles de cobre han sido asociados recientemente con la enfermedad de Alzheimer, mientras que los niveles bajos durante el embarazo causan ataxia enzoótica (swayback) enla descendencia. En este estudio investigamos el efecto prolongado del cobre sérico mantenido a 0.5 ppm ó alrededor de 0.5 ppm – el nivel considerado seguro actualmente. Ovejas y conejas preñadas, en el último trimestre (1-4 semanas) de gestación, fueron tratadas con el quelante del cobre conocido como tetratiomolibdato de amonio (TM). El tratamiento continuó hasta que las crías tuvieron un mes,momento en el que los animales fueron sacrificados. Los niveles séricos cúpricos de los progenitores y la progenie fueron monitoreados mediante absorción atómica. Se examinaron los espectros de diferencia (400– 630 nm). Se usó la técnica de SDS-PAGE para evaluar la composición proteica de lasmitocondrias cerebrales. También se estudió la anatomía del mesencéfalo. Aunque la anatomía de las crías de ovejas y conejas madres tratadas con TM no mostraron señales visibles de discapacidad o enfermedad swayback, el mesencéfalo de estas crías con cobre sérico entre 0.3–0.9 ppm, mostróevidencias de vacuolación, cavitación y cromatolisis. En contraste con ello, los espectros de diferencia y la composición proteica de las mitocondrias del cerebro de estos animales, fueron todos normales. Estos resultados sugieren que aunque los animales puedan parecer normales y presentar marcas bioquímicas normales, el cobre sérico en el rango de 0.5 ppm, puede no ser seguro para algunas crías de ovejas y conejos. Es posible que una situación similar se aplique al ser humano.

Evidence of collateralization of vagal efferents innervating subdiaphragmatic segments of the gastrointestinal tract in the rat using the double labelling fluorescent dyes technique

Collateralization of the abdominal vagal trunks was investigated in the rat using double labelling fluorescence dye technique. A total of 20 adult male and female rats were used for the study. The anterior and posterior walls of the corpus and fundus of the stomach were injected with 0.1 microliter (microliter) of 5 aqueous solution of diamidino yellow (Dy) in eight rats. The same quantity and percentage of fast blue (Fb) was injected into the walls of the duodenum and proximal jejunum in the same eight rats that were injected with Dy. The anterior and posterior walls of the stomach of four rats were injected with 0.1 microliter of 5 Dy only while four other rats had injections of 0.1 microliter of Fb only into the duodenum and proximal jejunum. Two control rats had stomach injections with normal saline, and two rats had saline injections into the intestine. Each rat was perfused with a preservative 14 days after injection and serial sections taken for examination with a fluorescence microscope. The results of the experiment revealed that in the eight rats injected simultaneously with Dy and Fb, some neurons of the dorsal motor nucleus of the vagus nerve (DMX) were labelled with Dy only, some with Fb only and some were doubly labelled with Dy and Fb. No double-labelled neurons were seen in the rat injected with one dye only and no labellings at all were seen in the controls. The pattern of labelling obtained in the study is suggestive of collateralization of axons of the abdominal vagal trunks