Use of Tithonia diversifolia (hemsl) A. Gray in the diet of growing lambs / [Uso de tithonia diversifolia (hemsl) A. Gray na dieta de cordeiros em crescimento]

Two assays were conducted to study the Tithonia diversifolia (Td) plant: (1) chemical analysis and in vitro dry matter digestibility (IVDMD) of plant parts and (2) productive performance of lambs fed a traditional diet or a Td diet (30% of Td plus 70% of the traditional diet). The plant parts studied were leaves (L), leaves and petioles (LP); and leaves, petioles and stems (LPS). Feed intake, weight gain and feed conversion were registered weekly during five weeks of experimentation. The L showed higher (P<0.05) crude protein content (26.7%) than LP and LPS (25.5 and 19.7%, respectively). Crude fiber (11.2%), neutral detergent fiber (45.4%), cellulose (16.9%) and hemicellulose (33.5%) were lower in L than in LP (12.5, 46.7, 18.0 and 35.7%, respectively) and LPS (22.6, 59.2, 27.0 and 43.5%, respectively). The L and LP showed the highest IVDMD (89.2 and 88.2%, respectively vs. 77.2% of LPS). The Td diet resulted in greater feed intake and weight gain and lower feed conversion than the traditional diet. Therefore, Tithonia diversifolia is a forage plant of good quality for lambs which does not affect the productive performance.(AU)

Dois ensaios foram realizados para estudar a planta de Tithonia diversifolia (Td): (1) análise química e digestibilidade in vitro da matéria seca (DIVMS) de partes de plantas e (2) desempenho produtivo de cordeiros alimentados com dieta tradicional ou dieta Td (30% de Td mais 70% da dieta tradicional). As partes vegetais estudadas foram folhas (L), folhas e pecíolos (LP); folhas, pecíolos e caules (LPS). O consumo de ração, o ganho de peso e a conversão alimentar foram registrados semanalmente, durante cinco semanas de experimentação. O L apresentou maior (P<0,05) conteúdo de proteína bruta (26,7%) que o LP e o LPS (25,5 e 19,7%, respectivamente). Fibra bruta (11,2%), fibra em detergente neutro (45,4%), celulose (16,9%) e hemicelulose (33,5%) foram menores em L do que em LP (12,5, 46,7, 18,0 e 35,7%, respectivamente) e LPS (22,6, 59,2, 27,0 e 43,5%, respectivamente). O L e o LP apresentaram o maior DIVMS (89,2 e 88,2%, respectivamente vs. 77,2% do LPS). A dieta Td resultou em maior consumo de ração e maior ganho de peso e menor conversão alimentar que a dieta tradicional. Portanto, Tithonia diversifolia é uma planta forrageira de boa qualidade para cordeiros que não afeta o desempenho produtivo.(AU)

Caveolae a new subcellular transport organelle

Recent advances have allowed the identification and characterization of well defined vesicular subcellular organelles involved in multiple basic cellular physiological processes, with demonstrated clinical relevance. Among these, three particular subcellular organelles have received special attention based on their proven and postulated participation in the sorting and targeting of small-and large-molecular weight molecules during exocytosis and endocytosis, and in cell signaling and transduction events. These have characteristic proteinaceous coat structures that allows their classification accordingly, into what has been described as clathrin coated vesicles and COP-coated vesicles and caveolae. In this review article a brief description of clathrin-coated vesicles and COP-coated vesicles is presented. Caveolae (CAV), in turn, constitute a novel subcellular organelle that has received special attention based on its proven and postulated participation in transcytosis, potocytosis, and in cell signaling and transduction events. In this review of the literature a more extensive discussion is presented of CAV. In this context the article discusses the structural features of caveolae, its constituent protein caveolin(s), the functional aspects of this new organelle, and its postulated clinical relevance

Long-term habituation (LTH) in the crab Chasmagnathus: a model for behavioral and mechanistic studies of memory

A decade of studies on long-term habituation (LTH) in the crab Chasmagnathus is reviewed. Upon sudden presentation of a passing object overhead, the crab reacts with an escape response that habituates promptly and for at least five days. LTH proved to be an instance of associative memory and showed context, stimulus frequency and circadian phase specificity. A strong training protocol (STP) (( 15 trials, intertrial interval (ITI) of 171 s) invariably yielded LTH, while a weak training protocol (WTP) (( 10 trials, ITI = 171 s) invariably failed. STP was used with a presumably amnestic agent and WTP with a presumably hypermnestic agent. Remarkably, systemic admministration of low doses was effective, which is likley to be due to the lack of an endothelial blood-brain barrier. LTH was blocked by inhibitors of protein and RNA synthesis, enhanced by protein kinase A (PKA) activators and reduced by PKA inhibitors, facilitated by angiotensin II and IV and disrupted by saralasin. The presence of angiotensins and related compounds in the crab brain was demonstrated. Diverse results suggest that LTH includes two components: an inital memory produced by spaced training and mainly expressed at an inital phase of testing, and a retraining memory produced by massed training and expressed at a later phase of testing (retraining). The inital memory would be associative, context specific and sensitive to cycloheximide, while the retraining memory would be nonassociative, context independent and insensitive to cycloheximide.

Tratamiento conservador del cáncer mamario / Consevative treatment of mammary cancer

Se presenta la experiencia en la Clinica de la Caja Nacional de Prevision de Bogota, sobre el tratamiento conservador del cancer mamario. En una primera revision sobre esta patologia que incluia las pacientes atendidas entre 1972 y 1982, cuando no se disponia de mamografo, el diagnostico del estado minimo tan solo alcanzo un 1.4 por ciento, el Estado I el 9.6 por ciento y el Estado II el 49 por ciento. En reciente revision que comprende los casos estudiados entre 1985 y 1992, cuando ya se disponia en esta Institucion del servicio de mamografia a partir de 1982, el diagnostico de los estados minimos alcanzo un 18 por ciento, los Estados I, un 34 por ciento y los Estados II, un 48 por ciento. Se establecen los criterios para practicar una cirugia conservadora, los que, además de un firme deseo de la paciente de conservar su seno, previa una completa informacion de su medico, deben ser: estados clinicos minimos, estados I y algunos II; tumores perifericos, preferentemente; buena relacion tumor-seno y facilidad para un buen control posterior de la paciente.

Retrograde amnesia in praying mantis after two successive learning processes

Learning and memory consolidation was investigated in the mantis Stagmatoptera biocellata, by two succesive trainings: a) the attak (A) avoidance training in which animals were not allowed to catch a mobile star, fallowed by the deimatic reaction (DR) avoidance training of not displaying this defensive response, or b) DR-avoidance training followed by A-avoidance training. The results showed that the presence and the 1 of A-avoidance learning and DR-avoidance learning did not affect the learning of the other training. Total retention of A-avoidance memory was demostrated when A-avoidance training was given first, whereas DR-avoidance memory was significantly lost (716%) when the DR-avoidance training was given first. The retroactive forgetting of DR-avoidance memory is considered as retrograde amnesia rather than retroactive memory inhibition because it depends on the activity during A-avoidance training (number of attacks) and not the quantity of A-avoidance learning. The magnitude of the amnesia effect due to this distracting activity in the A-avoidance training appears to be remarkably similar to that reported in a previous work using nitrogen-induced anoxia as the amnesia factor

Manometria del esofago en pacientes con manifestaciones digestivas altas. / Esophageal manometry in patients with upper digestive manifestations

Se valoran en el presente estudio 40 pacientes con diagnostico de trastornos funcionales digestivos altos que tenian 3 de los siguientes sintomas: regurgitaciones, sensacion de plenitud postprandial, imposibilidad de terminar las comidas, distension abdominal, agruras o pirosis, ardor epigastrico, eructos, nausea y vomito. A todos ellos se les practico estudio clinico completo, radiologia de las vias digestivas superiores, endoscopia y manometria esofagica por medios convencionales.Se demostro que la mitad de los pacientes tenian insuficiencia de presion en el esfinter esofagico ademas de que algunos de ellos presentan aumento de las contraciones en el cuerpo del esofago o disminucion en las mismas.El presente estudio parece mostrar que en los enfermos con supuestos trastornos funcionales digestivos altos, pueden haber combios importantes en las presiones del esfinter esofagico inferior, lo que podria tener relacion a su fisiopatologia. Se discute ademas la conveniencia de emplear medicamentos adecuados en estos pacientes al haberse descernido su funcion motora de manera mas correcta por metodos manometricos

Demostracion de la permeabilidad de la valvula de Leveen por medio de la inyeccion intra-abdominal de Tc 99. / Demonstration of Leveen shunt permeability by intraperitoneal injection of Tc 99

La derivacion peritoneo yugular es un metodo propuesto por Leveen para el control de ascitis refractaria. Esta derivacion se ha popularizado y su empleo se ha difundido rapidamente. En este trabajo se describe un metodo para investigar la permeabilidad de la derivacion. El metodo consiste en la inyeccion intraperitoneal de tecnecio radioactivo que al diluirse en el liquido de ascitis puede seguirse con una gammacamara y observarse el trayecto de la derivacion y su desembocadura a nivel yugular. El metodo fue utilizado en 3 pacientes con sospecha de oclusion de la derivacion, habiendose documentado la oclusion en un caso