Mariano del-Sol

Consejos para los Estudios de Morfología Cuantitativa (Morfometría y Estereología)

The quantitative morphology contributes to making the studies less subjective and reproducible. Quantitative results are analyzed with statistics and should be based on a well-defined sample. Quantitative variables can be ‘continuous’ or ‘discr ete. In this text, the term ‘morphometry’ is used to design a simpler procedure for measuring structures with a ‘ruler. The term ‘stereolog y’ is used in estimating quantities in the 3-dimensional space analyzing 2-D cut sections. Correction factors may be necessary for the retrac tion and compression of the tissues. In histological sections, the ‘caps’ of the objects that have been sectioned tangentially are lost when chemical agents remove the paraffin distorting the analysis. Moreover, the analyses based on digital images should consider the same for mat and the same size (pixels) to all pictures allowing a comparison between groups. Stereology can be ‘model-based’: points within a frame are counted to estimate the ‘volume density’ (Vv) of a structure, and intercepts are counted to assess the ‘surface density’ (Sv). Counting structures within a frame allow estimating the ‘length density’ (Lv). Newer and more complex ‘design-based’ procedures are cons idered unbiased. The key point is that design-based inference does not require assumptions about the material and uses the ‘random sam pling’ approach. The estimation of the number of objects requires a 3-D (volume) probe and therefore the ‘disector ’ technique. This re view aimed to contribute to the execution of the project, the correct sampling and the data obtained with morphometry and stereology.

Mandibular Trabecular Structures In Alveolar Ridge Preservation Using Different Grafting Materials After Tooth Extraction

The aim was to describe the star volume analysis in ridge preservation using different grafting materials. Bilateral extraction of the first mandibular molars of sixteen male rabbits was performed, divided at random into four groups (n= 4 in ea ch group) according to graft, using: blood clot (G1), xenograft (G2), pure phase beta-tricalcium phosphate (G3) and biphasic calcium phos phate (60 % HA / 40 % beta-TCP) (G4). Rabbits were euthanized at 4, 6, or 8 wk post-extraction; the trabecular bone structures was ev aluated by star volume analysis. The Levene test was used to analyze variance, as was the independent sample t-test. A P-value of < 0.0 01 was used to establish a statistically significant. The star volume analysis of the mandibular trabecula shows that the marrow space star volum (V*m.space) was higher than the trabecular star volume (V*tr). At 6-week post-extraction, new trabecular bone was evident. At 8 -w ek post-extraction V*tr increase in all groups and the V*m.space diminish, suggesting coarsening of the internal architecture. In G2, some trabecular bone was observed in the central region. In G3, most of the socket regions were occupied by newly formed and loose t rabecular bone and in the G4, the sockets were almost entirely filled with trabecular bone. Star volume analysis is adequate to analysis of bone patterns formation using bone substitutes.

Sexual Determination and Differentiation During Embryonic and Fetal Development of New Zealand Rabbit Females

The aim of this study was to know the embryonic and fetal development of the female rabbit genital system (Oryctolagus cuniculus ), describing its main phases and the moment of sexual differentiation. Eleven pregnant New Zealand female rabbits were used in different gestational phases. The day of coitus was determined as day 0. For each stage a minimum of two a nimals was considered. The samples were obtained every two days from the ninth day post-coitus (dpc) until the 28 th dpc. The gestational period was divided in two: animals with undifferentiated sex (group 1) and animals with differentiated sex (group 2). The ages of embr yos and fetuses were estimated through the crown-rump method. Subsequently, embryos and fetuses were dissected, fixed and processed to be embedded in paraffin (Histosec). The histological analysis was performed on sections stained with hematoxylin and eosin. Immunohistochemical analysis to determine sexual differentiation was performed on samples from the 16 , 18 and 28 dpc. Desert Hedgehog (Dhh) and Indian Hedgehog (Ihh) primary antibodies, respectively, were used to identify cells of the male and female g erminal epithelium. The immunohistochemical results showed that at the 16 th dpc, female sexual differentiation was evident, since positive expression of the Ihh protein was observed. Sexual differentiation was obtained through histological analysis on the 18 th dpc and through anatomical observation of the external genitalia on the 24 th dpc. Knowing the characteristics of the embryonic and fetal development of the female rabbit genital system as well as the moment of sexual differentiation make it possible to establish bases for future research that address the physiology and pathology of these organs. Thus, any alteration in the chain of events of sexual determination and d fferenti tion must search for an explanation from the knowledge of the possible normal mechanisms affected.

Proposal of Predictive Equations of Inspiratory Capacity and Maximum Spiratory Flow Considering Thoracic Measurements: A Pilot Study

RESUMEN: El objetivo del siguiente estudio fue determinar si las mediciones de tórax provocan modificaciones en las ecuaciones predictivas de capacidad inspiratoria (CI) y flujo espiratorio máximo (FEM). Se evaluaron 24 sujetos de sexo masculino entre 18 y 26 años, todos estudiantes sedentarios de la Universidad Católica del Maule, Chile. Se les realizó antropometría corporal básica ( eso y talla corporal) y específica de tórax, diámetro antero-posterior (DAT) y transverso (DTT) de tórax y perímetro mesoesternal (PME). Po sterior a esto, se evaluó la función ventilatoria a través de pletismografía corporal. Para estimar las ecuaciones de regresión lineal s utilizó l método de mínimos cuadrados relacionando la CI y FEM. La comparación entre el valor predicho establecido y nuestra propuesta fu e comparado utilizando la prueba t de student o U de Mann-Whitney según correspondiera, considerándose un nivel de significancia estadística de p<0,05. Los resultados indican que para la propuesta de la ecuación de FEM se consideró el DTT y PME, logrando diferencias significativas con los valores de Knudson et al. Por tanto, se concluye que las mediciones de DTT a VR y PME a CPT influyeron en la ecuación predictiva de FEM en estudiantes sedentarios.

Epoxy Sheet Plastination on a Rabbit Head - New Faster Protocol with Biodur® E12/E1

Plastination is an anatomical technique of cadaveric preservation that allows the preservation of anatomical pieces indefinitely, in dry and odorless form. It was created in 1978 by Gunther von Hagens, in Heidelberg, Germany. In particular, th e sheet plastination technique, with epoxy resin, allows the generation of thin sections of various anatomical regions, allowing an acc urate visualization of anatomical structures of difficult access through dissection or cadaveric exploration. The aim of this work wa to present a new sheet plastination protocol with Biodur® E12/E1, which is faster in its implementation, applied, for the first time, in a rabbit head.

Effects of High-fat Diets on Biochemical Profiles and Morpho- Quantitative Characteristics of C57BL/6 Mice Adrenal Glands

According to the information provided by the World Health Organization (WHO), overweight and obesity are the fifth leading causes of death in the world. Due to the alarming increase of this disorder in recent years, studies have been ca rri d out to evidence harmful effects on human or animal tissues. Our objective was to evaluate the morphological and physiological changes of C57BL/6 mice adrenal glands (AGs), associated with high fat diets (HFDs), we used 14 male mice, 5 months old, fed for 14 weeks according to two diets. The standard chow group (SC) was fed AIN-93M and the high fat group (HF) was fed AIN-93M-HF. At the end of the experiment, biometric analysis was performed and euthanasia was performed. Blood was then extracted for biochemical anal ysis and AGs were processed for mesoscopic, histological, morphometric and stereological studies. We used Student’s t-test (p<0.05) for statistical analysis. SC group showed a lower weight (29.67 ±1 28 g) with respect to the HF group (38.46 ± .68 g, p=0.002). COL-T, HDL-C, TG and CORT analysis revealed differences between SC group and HF (p ≤0.001). Focally, in the fasciculate area, there was an increase in the core-cytoplasm ratio and a greater lipid vacuole presence and size. There was a significant reduction (p=0.001) in V vfas =7.365±3.326 % of the HF group fasciculate area compared to SC group (V vfas =9.619±4.548 %). Obesity induced by HF diets affects adrenal gland physiology and morphology of mice. Our results suggest that both the percentage of fat as well as the time of adm inistration of the diet, produce a diurnal reduction of corticosterone, which could be due to an increase in the metabolic clearance of thi s hormone and not to the inhibition of the Hypothalamus-Pituitary-Adrenal (HPA) axis.