Repositorio académico de acceso abierto (Univ. Autonóma de Chile)
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Radiographic and electromiographic study of masseter and temporal anterior muscles in subjects with angle ii, i malloclusion and controls [Estudio radiográfico y electromiográfico de los músculos masetero y temporal anterior en individuos con maloclusión tipo ii, 1 de angle y controles]
No full textThe of this study is compare the electromiographic activity (EMG) of the Masseter (Ms) and Temporal Anterior (Ta) muscles in subjects with malocclusion Angle II, I and controls. This study involving 19 young adults with similar anthropometric characteristics (Age, weight, hight, BMI). We evaluate clinical and radiographicaly this subject and divided it in to groups: Control Group CG with neutrocclusion and Distal Group (DG) with Angle II, I malocclusion. The both groups was submit a surface EMG according to Ferrario et al. (1993). We used the root mean square (RMS) math operation to calculate the mean voltage amplitude for each muscle. Furthermore we calculate the ratio Ms/Ta and the distribution of voltage class determinate for motor units actions potentials (MUAP). The Rx examination included SNA, SNB and ANB angles according to Steiner (1992), alfa angle and lever arm of Ms according the Throckmorton et al. (1980) mandibular model. The Stundent "t" Test was used to determine whether there were significant differences (p<0.05) between CG and DG parameters. The voltage amplitude was more higher in DG than CG. The ratio Ms/Ta showed protagonism of Ms in CG. The alfa angle and lever arm of Ms were more greater in DG than CG. DG presents a poor number of voltage class (57.8%) respect to CG (79.0%). DG presents a greater voltage amplitude in relation to CG, probably because the feedback inhibitory periodontal tissue plays an important role. Moreover DG presents a low voltage classes distribution of MUAP that suggest that have minus functional reserve.Universidad Autónoma de Chil
Biometric and morphological charachteristics of the fibrous pericardium and the diaphragm in man [Aspectos biométricos y morfológicos del pericardio fibroso y diafragma en el hombre]
No full text[No abstract available]Universidad Autónoma de Chil
Morphometric evaluation of the embryo-uterine relationship of the pre and post implantational stages in rabbit (Oryctolagus cuniculus) [Evaluación morfométrica de la relación embrio-uterina de las etapas pre y post implantacional en conejo (Oryctolagus cuniculus)]
No full textThe rabbit has demonstrated to be an outstanding implanting model. As an obligated ovulating animal, its pregnancy time can be established exactly. The morphologic observation of uterus cuts of 7, 8, 9 and 10 days post mating, allowed this research to rebuild an apparent sequence morphometric events, that take place during rabbit implantation. Twenty New Zealand, white, adult, female rabbits were used in this research. (Oryctolagus cuniculus), nulipara. And 4, proven, fertile, males were used for mating. These males were obtained from the Bioterio of the Faculty of Medicine at the Universidad de La Frontera, Temuco, Chile. Mating day was defined as day cero, sacrificing the females days 7, 8, 9 and 10 in each mating. Once sacrificed, the pelvic region was macro and mesoscopically dissected, and the vesicles were selected for histological and immunocitochemical study. Histological studies were performed with H.E. technique; morphometric and cellular kinetics with Tunnel and PCNA techniques. Descriptive statistics was used based on an average and standard deviation (p<0.001). The Stata 9.0 statistical program was used. The morphometric measurements obtained were: diameters and volume of the uterine vesicle, height of the uterine wall and glandular lumen of the mesometrial and antimesometrial regions to 7-10 days post coitus. The immunocitochemical analysis identified: apoptotic index of the cellular nucleous and cellular mitotic index. By day 8 post coitus were observed significant morphometric changes at the vesicular lumen, height of the uterine wall of the mesometrial region and glandular lumen. For the same day important changes of the cellular mitotic index and apoptotic index were observed. The rabbit could be a species used to predict normal embryo development, after the morphologic comprehension of the implantation, given its not so invasive form of implantation and its capacity of early placenta formation. Providing updated information in the normal development of the rabbit embryo and in vivo implantation, is an interesting move ahead for in vitro embryo cultivation.Universidad Autónoma de Chil
Comparative stereology between the spleen of the guinea pig (Cavia porcellus) and the rat (Rattus novergicus, Sprague Dawley) [Estereología comparativa entre el bazo del cuye (Cavia porcellus) y la rata (Rattus novergicus, Sprague Dawley)]
No full textThe spleen is the largest peripheral lymphoid organ of the body so it is essential to know their morphological quantitative aspects in order to identify potential abnormalities. The aim of this study was to determine the parameters stereological spleen in normal two species commonly used in research such as the guinea pig and rat, to obtain quantitative patterns of normality, which will serve as a basis for future studies morphofunctional. 5 spleens were used for each species (Cavia porcellus and Rattus novergicus, Sprague Dawley) obtained from biotery the Universidad de La Frontera, Temuco, Chile. The spleens were dissected and fixed in formalin buffered to 10% and the volume is determined by the of Scherle method. 5 pieces were obtained through Orientator and these were included in paraplast. Each piece was performed histological cuts of 3 mm thick and separated 200 μ m each other, which were stained with H-E. The percentage of red pulp, white pulp and marginal zone in the Guinea pig was: 65.14%, 21.96% and 12.67% respectively, and in the rat 53.9% pulp red, 25.75% white pulp and 15.87% of marginal zone.The total number of follicles was 8.33 × 102 follicles and 5.73 × 102 follicles for the Guinea pig and rat, respectively. The results are consistent with those obtained by other authors might identify a pattern of quantitative percentage of splenic compartments of normality that could be considered for future studies morpho-functional
Characterisation of the gene family encoding acetoacetyl-CoA thiolase in Arabidopsis
No full textThiolases are ubiquitous enzymes involved in many essential biochemical processes. Biosynthetic thiolases, also known as acetoacetyl-CoA thiolases (AACT), catalyse a reversible Claisen-type condensation of two acetyl-CoA molecules to form acetoacetyl-CoA. Here, we report the characterisation of two genes from Arabidopsis thaliana L., ACT1 and ACT2, which encode two closely related AACT isoforms (AACT1 and AACT2, respectively). Transient expression of constructs encoding AACT1 and AACT2 fused to GFP revealed that the two proteins show a different subcellular localisation. While AACT1 is found in peroxisomes, AACT2 localises in the cytosol and the nucleus. The peroxisomal localisation of AACT1 depends on the presence of a C-terminal peroxisomal targeting sequence (PTS1) motif (Ser-Ala-Leu) not previously found in other organisms. ACT1 and ACT2 genes are also differentially expressed. Whereas ACT2 is expressed at relatively high level in all plant tissues, the expression of ACT1 is restricted to roots and inflorescences and its transcript is present at very low levels. The obtained results are in agreement with the involvement of AACT2 in catalysing the first step of the mevalonate pathway. The metabolic function of AACT1 is not clear at present, although its particular peroxisomal localisation might exclude a role in isoprenoid biosynthesis. © CSIRO 2008
The breastfeeding mother and the workplace [La madré que amamanta y el entorno laboral]
No full textThe purpose of this review of the literature is to assess the current situation of the working mother and the influence of the workplace and support on the part of the family, the employer and health care professionals in the effort to achieve successful breastfeeding. The authors describe the situation in Chile and provide guidelines and strategies that the midwife, in accordance with her professional competence, can develop in her sphere of practice in order to improve the quality of life of future generations.Universidad Autónoma de Chil
Challenges for researchers in education in Latin American Desafios para os pesquisadores em educação da America Latina [Desafíos para los investigadores en educación de América Latina]
No full textResearch about the causes of poor reading comprehension, as verified by UNESCO, is essential. The slow progress of the Education for All Program (EFA) suggests studying the determinants of acceptable quality. The experience of developed countries invites the finding of trustable modalities for innovation with success in education. These three subjects imply experimenting systematically with better training programs for teachers and evaluating their impact on student learning. The article discusses recent reviews of pertinent studies, the elements to research, and the precautions to take in consideration with each of them.Universidad Autónoma de Chil
Enhancement of a QRS detection algorithm based on the first derivative, using techniques of a QRS detector algorithm based on non-linear transformations
No full textThis work shows details of the implementation of a QRS complex detector Algorithm, based on the first derivative (Holsinger Algorithm), and includes characteristics of a more elaborate QRS detector based on Non-linear transformations(Hamilton-Tomkins Algorithm). These extensions are manifested by the use of a Refractory Period for the search horizon, decision rules using adaptive thresholds for detecting the QRS complex, and a pre-processing of the signal using a Band-pass filter, which maximizes the energy of the QRS complex. The performance of both algorithms is compared using some of the MIT Arrhythmia database records. © 2009 Springer Berlin Heidelberg.Universidad Autónoma de Chil
Stereological study of the guinea-pig liver (Cavia porcellus) [Estudio estereológico del hígado de cobayo (Cavia porcellus)]
No full textThe liver is a widely researched organ for having an infinity of functions. On the other hand, Stereology allows the access of quantitaive data of the study's structure. Having access to this tpe of date of hepatocitos and sinusoids Under normal physiological conditions, it is necessary to determine how the number of these cells varies in pathological conditions. The principal objective of this investigation was to describe the morphology of the liver of cobayo, through Stereology, setting the bases for future morphofuncional investigations. Five adult males of the Cavia porcellus species were used, of which the liver was extracted and its volume determined, applying the Scherle method. Subsequently five pieces of aleatoria form were obtained which were set in an aqueous Bouin solution. Of these samples 3μm cuts were obtained, that were dyed with hematoxilina-eosina. For the stereological study the M42 system was used. The following were determined: the number densities, volume and surface and total number of hepatocitos and sinusoides. An index of lesser significance or equal to 0,05. The NV of hepatocitos was 9.20 x 105 /mm 3, VV de 70.04% and SV of 254.95 mm2/mm 3. In the case of the sinusoides NV was 1.94 x 105 /mm3, VV of 24.86% and SV de 47.01 mm2/mm3. The total number of hepatocites was of 2.8 x 107 and sinusoides 0.61 x 107. While comparing the results obtained in Cavia porcellus and those obtained in other species, a quantitative variation in the hepatic morphology is observed. With these results it is possible to establish the bases for experimental research .Universidad Autónoma de Chil