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Zoledronic acid (ZA) is an antiresorptive drug used in children with bone diseases like osteogenesis imperfecta, juvenil osteoporosis, fibrous dysplasia and primary bone tumors. The aim of the present study was to evaluate the effects of ZA dose accumulation on growing bone during different periods of treatment in normal rats. Methods: A 4x2 factorial design was used to study the effect of the dose of ZA (D: 0-2.5-12.5-25 µg Z/kg body weight/s.c. weekly) and the length of treatment (T: 15-30 days) in normal female Sprague Dawley rats. Bone morphometric, histomorphometric, densitometric and biomechanical studies were performed. Results: Femoral length and cross-sectional area were affected by both D and T. A significant interaction between D and T was observed in length with a lower value at higher dose and 30 days of treatment. Growth plate of the tibia showed a decrease in total thickness with D and T. Histomorphometric and connectivity parameters of trabecular bone were significantly increased with D and several parameters were also affected by T. Cortical bone strength was increased only with T. Biomechanical parameters of trabecular bone showed significant interaction with greater effect at higher D and T. Conclusion: Even though a mild negative effect of the highest dose of ZA on linear and appositional growth was observed, the other bone parameters evaluated were improved. A careful risk/benefit analysis would lead us to conclude that the mild deleterious effects of ZA during growth are outweighed by the benefit obtained with treatment. (AU)

El ácido zoledrónico (AZ) es un fármaco antirresortivo utilizado en niños con enfermedades óseas como osteogénesis imperfecta, osteoporosis juvenil, displasia fibrosa y tumores óseos primarios. El objetivo del presente estudio fue evaluar los efectos de las dosis acumuladas de AZ en el hueso en crecimiento de ratas hembras normales durante diferentes períodos de tratamiento. Métodos: se utilizó un diseño factorial de 4x2 para estudiar el efecto de la dosis de AZ (D: 0-2,5-12,5-25 µg Z / kg de peso corporal /sc semanalmente) y el período de tratamiento (T: 15-30 días) en ratas Sprague Dawley. Se realizaron estudios óseos morfométricos, histomorfométricos, densitométricos y biomecánicos. Resultados: la longitud y el área de sección transversal del fémur se vieron afectadas tanto por D como por T. Se observó una interacción significativa entre D y T en la longitud obteniéndose un valor más bajo a la dosis más alta y a 30 días de tratamiento. El cartílago de crecimiento de la tibia mostró una disminución en el espesor total con D y T. Los parámetros histomorfométricos y de conectividad del hueso trabecular aumentaron significativamente con D y varios parámetros también se vieron afectados por T. La fortaleza ósea cortical aumentó solo con T. Los parámetros biomecánicos del hueso trabecular mostraron una interacción significativa con un mayor efecto a mayor D y T. Conclusión: a pesar que se observó un leve efecto negativo de la dosis más alta de AZ sobre el crecimiento lineal y aposicional, el resto de los parámetros óseos evaluados mejoraron. Un análisis cuidadoso del riesgo /beneficio permite concluir que los efectos negativos leves del AZ durante el crecimiento son superados por el beneficio obtenido con el tratamiento. (AU)

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Some environmental interventions can result in physiologic and behavioral changes in laboratory animals. In this context, the handling of adolescent or adult rodents has been reported to influence exploratory behavior and emotionality. Here we examined the effects of handling on memory and anxiety levels of adolescent rats. Male Sprague-Dawley rats (age, 60 d) were divided into a control group and a handled group, which were handled for 5 min daily, 5 d per week, for 6 wk. During handling bouts, the rat was removed from its cage, placed in the experimenter's lap or on the top of a table, and had its neck and back gently stroked by the experimenter's fingers. During week 6, each rat's anxiety level was evaluated in the elevated plus-maze (EPM) test. Learning and memory were evaluated 48 h later, by measuring escape latency in the elevated plus-maze test. Plasma corticosterone and catecholamine levels were measured also. Norepinephrine levels were lower in the handled rats compared with control animals, with no differences in epinephrine and corticosterone. As compared with the control rats, the handled rats showed increases in the percentage of time spent in the open arms of the test apparatus, percentage of entries into open arms, and number of visits to the end of the open arms and decreases in the latency of the first open arm entry. Escape latency was lower in the handled rats compared with control rats in both the first and second trials. The data obtained suggest that handling decreases anxiety levels and improves learning skills and memory in rats.

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Increasingly the use and convenience of electrical appliances in our daily lives are the cause of harmful effects caused by electromagnetic fields (EMF). The aim of this study was to research the effect of EMF on the ultrastructure of the heart in EMF exposed rats. In this study 45 male Sprague Dawley rats ranging in weight between 260 and 280 grams were used. The rats were divided into 3 groups, control (n:15), Sham (n:15) and EMF group (n: 15) and exposed for 14 days 3 hours per day; gauss levels at 2.5 were applied to the EMF group, while the sham group in the same environment in Plexiglas cage was kept for 14 days 3 hours per day without magnetic field exposure. Control group at 14/10 hours light dark cycle fed in normal cages for 14 days. After two weeks rats were sacrificed by 50mg/kg of Ketalar anesthesia and heart tissue fixed in 2.5 gluteraldehide. Routine follow up with electron microscopic assessment. Mitochondrial structures and cellular structures observed in all the groups were normal. Myofibrillar loss, dilatation of smooth endoplasmic reticulum, mitochondrial swelling or cristalysis was not observed. Intercalated disc degeneration and apoptosis of nucleus was not observed. Therefore, and as a result of our study we did not observe differences between control and EMF groups.

El uso y la comodidad de los aparatos eléctricos en nuestra vida cotidiana cada vez más son causa de efectos perjudiciales debido a los campos electromagnéticos(CEM).El objetivo de este estudio fue investigar el efecto de los CEM sobre la ultraestructura del corazón en ratas. Fueron utilizadas 45ratas Sprague Daw ley, con peso entre 260 y 280gramos. Las ratas fueron divididas en 3 grupos: control (n: 15); Sham (n:15), y grupo expuesto a CEM (n:15) durante 14 días,3 horas por día. Se aplicó niveles de 2,5gaussal grupo expuesto a CEM, mientras que el grupo de tratamiento simulado en el mismo entorno en jaulas plexiglás se mantuvo durante 14 días 3 horas día, sin exposición a campo electromagnético. Grupo control alimentado en jaulas normales durante 14 días con ciclo luz/oscuridad de 14/10. Al termino de dos semanas las ratas fueron sacrificadas por medio de anestesia Ketalar 50mg/kg y el tejido del corazón fijado engluteraldehido al 2,5. Se realizó seguimiento de rutina con correspondiente evaluación de microscopía electrónica. Las estructuras mitocondriales y celular es observadas en todos los grupos eran normales. No se observó pérdida miofibrilar, tampoco aumento del volumen mitocondrial ni dilatación del retículo endoplásmico lisoocristalysis. No se observó degeneración de los discosintercaladoso apoptosis de núcleo. Por lo tanto,y como resultado de nuestro estudio no encontramos diferencias entre los grupos control y CEM.

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Ubiquitous consumption of Momordica charantia is hinged on credence of its potency in alleviating ailments. Almost no data exist on its quantitative relationship to the testes. The aim was to study the histomorphometric effect of Momordica charantia seed extract (MC), ascorbic acid (C), alpha-tocopherol (E) and testosterone (T) on the testes of rats. Ninety five mature 6-8 week-old male Sprague-Dawley (S-D) rats allotted randomly into six groups. Group I: fed MC for 16 weeks. Group II: administered MC for 8 weeks, later distilled water for another 8 weeks. Group III: administered C, E, T and a combination of all three test solutions (CET) for 8 weeks and later fed MC for another 8 weeks. Group IV: received MC initially for 8 weeks and later administered C, E, T and CET for another 8 weeks. Group V: fed concurrently the extract, C, E, T and CET for 8 weeks. Group VI (control): administered C, E, T, CET and distilled water for 16 weeks. The doses for MC, C, E and T were 50 mg/100 g b.w/oral/day, 0.01, 20.0 and 0.05 mg/kg. The animals were sacrificed; testes estimated for volume. Diameter, cross sectional area (AC), number of profiles per unit area (NA), length density (LV) and numerical density (NV) of the seminiferous tubules determined. The mean testicular volumes, tubular diameters and AC showed significant decline (p 0.05) in Groups I and III compared to controls. On cessation of MC values recovered to baseline control value. Groups IV and V, were not significantly (p 0.05) different from controls. There was a significant (p 0.05) increase in NA, LV and NV of seminiferous tubules in Groups I and III compared to controls. Histomorphometric data supports a reversible deleterious effect of MC on testes.

El consumo ubicuo de Momordica charantia ha girado en torno a su potencial participación en el alivio de dolencias. El objetivo fue estudiar los efectos del extracto de la semilla de Momordica charantia (MC), ácido ascórbico (C), alfa-tocoferol (E) y testosterona (T) sobre parámetros histomorfométricos en testículos de ratas. Noventa y cinco ratas machos Sprague-Dawley (S-D) maduras (6-8 semanas de edad) fueron asignadas al azar en seis grupos. Grupo I: alimentados con MC durante 16 semanas. Grupo II: MC administrado durante 8 semanas, luego agua destilada por otras 8 semanas. Grupo III: C, E, T administrados junto a una combinación de las tres soluciones de prueba (CET) durante 8 semanas y luego alimentados con MC por otras 8 semanas. Grupo IV: MC inicialmente durante 8 semanas y posteriormente C, E, T y CET por otras 8 semanas. Grupo V: alimentado al mismo tiempo con el extracto, C, E, T y CET durante 8 semanas. Grupo VI (control): administrado con C, E, T, CET y agua destilada durante 16 semanas. Las dosis de MC, C, E y T fueron de 50 mg/100 g de peso corporal/oral/día, 0,01, 20,0 y 0,05 mg/kg. Los animales fueron sacrificados y se estimó el volumen de los testículos. El diámetro, área de sección transversal (AC), el número de perfiles por unidad de área (NA), la densidad de longitud (LV) y la densidad numérica (NV) de los túbulos seminíferos fueron determinados. Los volúmenes medio testicular, diámetro de túbulos y AC mostraron una disminución significativa (p 0,05) en los grupos I y III en comparación con los controles. Al quitar MC, los valores se recuperaron al valor basal de control. Los grupos IV y V, no fueron significativamente diferentes de los controles (p 0,05). Hubo una diferencia significativa (p 0,05) con aumento de la NA, LV y NV de los túbulos seminíferos de los grupos I y III en comparación con los controles. Los datos histomorfométricos apoyan la reversibilidad de los efectos nocivos de la MC en los testículos.

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Summary: Lantana camara is used in herbal medicine for the treatment of skin itches, as an antiseptic for wounds, and externally for leprosy and scabies. The objective of our study is to investigate burn wound healing activity of the leaf extract of L.camara in rats. The animals were divided into two groups of 6 each. The test group animals were treated with the ethanol extract of L. camara (100 mg kg-1 day-1) topically and the control group animals were left untreated. Healing was assessed by the rate of wound contraction, period of epithelialization. Antimicrobial activities of the extract against the specific microorganisms were assessed. The extract showed antimicrobial activity against Staphylococcus aureus, Klebsiella Pneumoniae and E.coli. Extract treated wounds were healed in about 21 days which is not distinct from the controls. Our data suggest that L.camara has antimicrobial activity but not wound healing promoting activity on burn wound. Industrial relevance: Extensive work has been done on the L. camara and demonstrated the antimicrobial and fungicidal activity of its chemical constituents. Lantana oil is used for the treatment of skin itches and as an antiseptic for wounds. It has been used in folk medicine for the treatment of cancers, chicken pox, measles, ulcers, swellings, eczema. Our earlier work showed the healing activity on excision wound model. However, there is no data to support the wound healing activity of L. camara on burn wound. Hence, we have conducted the present study to explore the wound healing activity and the antimicrobial activities of L. camara against the specific microorganisms which generally infect burn wound.

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Se ha demostrado efectos cronótropos e inótropos negativos de los ácidos biliares (AB). Sin embargo, se sabe que éstos pueden aumentar la concentración de calcio intracelular, sugiriendo una acción estimulante sobre el corazón. Por esta razón se investigó posibles efectos estimulantes de los AB sobre automatismo y contractilidad cardíaca. En preparaciones sinoatriales con actividad espontánea se estudiaron los efectos de AB sobre la frecuencia sinusal (FS) y en músculos papilares estimulados a frecuencias constantes se analizaron las acciones sobre fuerza contráctil. Los ácidos cólico y taurocólico disminuyeron la FSde forma similar a todas las concentraciones usadas. Se sugiere que el efecto cronótropo negativo es debido, por lo menos en parte, a una disminución de la corriente Isi y a un aumento de la corriente Ik. Sin embargo, no es posible descartar acciones sobre otras corrientes iónicas en especial If. Ambos ácidos tuvieron efecto inótropo positivo que puede deberse a inhibición de la ATPasa sodio-potasio, aunque no es posible descartar la existencia de otros mecanismos. En resumen, lo AB tienen efectos sobre el automatismo del nódulo sinusal y la contractilidad miocárdica que permite considerarlos como agentes digitalis-like

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A reference database comprising body weight gain, exploratory activity, hot plate response, serum biochemistry, haematology, organ weight (%) and a complete anatomopathological study containing non-neoplastic and neoplastic lesions over 1200 Sprague-Dawley rats from 6 to 32 months is described. Comparisons between age and sex were analysed.

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Se efectuó la standarización de la rata Sprague-Dawley en relación a parámetros hematológicos, bioquímicos y anatómicos en una muestra de 24 ratas, 12 machos y 12 hembras. Se estandarizó el modelo de asa duodenal cerrada para producir pancreatitis aguda en 72 ratas, las que fueron sacrificadas en grupos de 3 cada hora durante 24 horas. Se determinó que el momento en que se inicia la pancreatitis aguda, tanto por parámetros bioquímicos como histopatológicos, corresponde a la sexta hora postinducción. Utilizando este modelo se efectuaron diferentes acciones tendientes a disminuir los efectos de una PA de inicio reciente. Cien ratas fueron divididas en 5 grupos de 20: 1. Control, 2. Descompresión biliar precoz, 3. Verapamilo 0,5 mg/kg ev., 4. Allopurinol 50 mg/kg ev., 5. Superóxido dismutasa 5 mg/kg ev. Para determinar el efecto benéfico de estas acciones sobre la PA, ellas fueron realizadas a la sexta hora postinducción. Se concluye que los mejores efectos logrados en este modelo corresponden a la desobtrucción efectuada precozmente. Dentro de las drogas utilizadas, como drogas captadoras de radicales libres de oxígeno, la superóxido dismutasa fue la que presentó los mejores efectos benéficiosos. El allopurinol mostró efectos discretos en este modelo, no comprobándose el efecto beneficioso del verapamilo en relación al grupo control

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Transamination reaction is the first step in the catabolism of most of the L-amino acids. Alanine is an important molecule in the inter-organ nitrogen transport, conveying them from muscle to the liver Amino groups from this amino acid are generally first transferred to alfa-ketoglutarate in the cytosol of liver cells to form glutamate and leaving behing the corresponding alfa-keto acid analog. Measurements of the alanine aminotransferase (EC2.6.1.2.) activity were compared in liver, mammary gland an skeletal muscle in virgin, lactating and weaning dam rats. In this study liver was the principal tissue involved in alanine transamination, while muscle showed a reduction in the enzyme activity during lactation. Results indicate an increase in alanine aminotransferase activity in the mammary gland during lactation and weaning when compared with virgin rats. This suggest that mammary gland during lactation is an importan extra-hepatic tissue involved in the metabolism of alanine and probably shunted into hte pathways for amino group metabolism in terms of nitrogen economy

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Sulphadoxine-pyrimethamine preparations are antimalaria drugs which owe their efficacy to their antifolate properties. Folates are essential for DNA synthesis and their deficiency at critical periods in gestation have been shown to be teratogenic in variious animals including man. This experiment has shown that, when administered to Sprague Dawley rats at certain periods in gestation, the activities of some enzymes essential for gonadonal steroidogenesis, such as delta 5-3-beta hydroxysteroid dehydrogenase (delta 5-3(HSD), 17-beta hydroxysteroid dehydrogenase (17 beta-HSD), and Glucose-6-phosphate dehydrogenase (G-6-PD) were found to be significantly reduced in the gonads of their litters (AU)

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