Consuelo Junqueira Rodrigues

The value of teaching sectional anatomy to improve CT scan interpretation.

A specific course on sectional anatomy was developed to help medical students improve their knowledge of cross‐sectional imaging. The educational methodology consists of identifying anatomical structures displayed in plastinated sections from human cadavers and corresponding anatomical structures in computed tomography (CT) sections from healthy patients. The course has a self‐study format. To assess and verify the impact of learning sectional anatomy on radiological knowledge, students were asked to identify ten anatomical structures in CT images. This test was applied to two groups of students: Group I had been taught sectional anatomy with CT images 2 years before the test; Group II had not received instruction in sectional anatomy prior to the test. Analysis of the results revealed a significant difference in test scores (median percentages of correctly identified structures) between Group I and Group II, with scores of 100% and 63.4%, respectively. These results provide evidence that the inclusion of sectional anatomy training in medical school curricula has a great impact on subsequent CT interpretation. Clin. Anat. 14:36–41, 2001.

Quantitative analysis of collagen and elastic fibers in the transversalis fascia in direct and indirect inguinal hernia

PURPOSE Our previous studies demonstrated structural and quantitative age-related changes of the elastic fibers in transversalis fascia, which may play a role in inguinal hernia formation. To verify whether there were differences in the extracellular matrix between direct and indirect inguinal hernia, we studied the amount of collagen and elastic fibers in the transversalis fascia of 36 male patients with indirect inguinal hernia and 21 with direct inguinal hernia. MATERIAL AND METHODS Transversalis fascia fragments were obtained during surgical intervention and underwent histological quantitative analysis of collagen by colorimetry and analysis of elastic fibers by histomorphometry. RESULTS We demonstrated significantly lower amounts of collagen and higher amounts of elastic fibers in transversalis fascia from patients with direct inguinal hernia compared to indirect inguinal hernia patients. The transversalis fascia from direct inguinal hernia patients showed structural changes of the mature and elaunin elastic fibers, which are responsible for elasticity, and lower density of oxytalan elastic fibers, which are responsible for resistance. These changes promoted loss of resiliency of the transversalis fascia. CONCLUSION These results improve our understanding of the participation of the extracellular matrix in the genesis of direct inguinal hernia, suggesting a relationship with genetic defects of the elastic fiber and collagen synthesis.

Aging of the elastic and collagen fibers in the human cervical interspinous ligaments

BACKGROUND CONTEXT The ligaments consist of collagen bands intermingled with elastic fibers that support hundreds of pounds of stress per square inch. In the spine the basic functional unit comprises vertebrae, intervertebral disc and ligament tissues. The interspinous ligaments with the function of limiting the spine flexion are exposed to a traumatic and degenerative process that promotes pain or instability. It has been shown that aging induces structural changes to capsular, fascial and ligamentous structures, mainly to the elastic and collagen fibers. However, the relative changes with age in elastic and collagen fibers have not been quantified. PURPOSE Examine the changes in the arrangement and amount of the elastic and collagen fibers of the human cervical interspinous ligament and attempt to correlate them with age. STUDY DESIGN/SETTING Histomorphometric analysis of ligament samples harvested during surgery. PATIENT SAMPLE We studied the dorsal portion of this ligament from 17 patients aged 16 to 69 years. OUTCOME MEASURES Fraction of collagen and elastic fibers with linear regression analysis correlating fraction versus age. METHODS The elastic and collagen fibers were identified by selective staining methods, and a blinded investigator using an image analysis system performed the histomorphometry. RESULTS There is an age-related progressive increase in collagen and mature and elaunin elastic fibers responsible to elasticity. However, these elastic fibers showed structural degenerative changes with aging. Furthermore, there is an age-related decrease of oxytalan elastic fibers responsible to resistance. CONCLUSIONS The aged interspinous ligament showed loss of elasticity that could alter the flexion limiting of the vertebral column.

Stem Cells from the Fat Tissue of Rabbits: An Easy-To-Find Experimental Source

Stem cells, because of their pluripotentiality and unlimited capacity for self-renewal, project great promise for tissue engineering and are expected to allow significant advances for distinct reconstructive procedures. This study aimed to establish a versatile experimental model with potential application to distinct lines of research in plastic surgery. The search was guided by the need for mesenchymal stem cells that can be easily obtained for laboratory research. The authors studied the anatomy of a number of animals as potential donors and indicated the white New Zealand rabbit (Oryctolagus cuniculus) for this purpose. The animals of this species present definite areas of lipid tissue on their back, allowing easy access to the tissue by either exeresis or liposuction.

Presence of apolipoprotein E ε4 allele in cerebral palsy

The apolipoprotein E gene, which is located on chromosome 19, has three alleles (ϵ2, ϵ3, and ϵ4). Several recent publications associate the presence of the apolipoprotein E ϵ4 allele with the occurrence of neurologic diseases, and consider it a risk factor for the development of central nervous system affections. A group of 40 patients with cerebral palsy was studied and compared to a control group of 40 subjects, and higher occurrence of the allele ϵ4 in the group of subjects with cerebral palsy was observed. A significantly higher risk of developing cerebral palsy was demonstrated among those subjects with the apolipoprotein E ϵ4 allele.

Effects of treatment with gonadotropin releasing hormone agonist on the uterine leiomyomata structure.

Objective. Our aim was to study the effects of the gonadotropin releasing hormone agonist on the uterine leiomyoma of infertile women.

Variation in the Distribution of Trace Elements in Renal Cell Carcinoma

The development of cancer is a complex, multistage process during which a normal cell undergoes genetic changes that result in phenotypic alterations and in the acquisition of the ability to invade other sites. Inductively coupled plasma optical emission spectroscopy was used to estimate the contents of Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, P, Pb, and Zn in healthy kidney and renal cell carcinoma (RCC), and significant differences were found for all elements. Along with the progression of the malignant disease, a progressive decrease of Cd and K was observed. In fact, for Cd, the concentration in stage T4 was 263.9 times lower than in stage T1, and for K, the concentration in stage T4 was 1.73 times lower than in stage T1. Progressive accumulation was detected for P, Pb, and Zn in stage T4. For P, the concentration in stage T4 was 11.1 times higher than in stage T1; for Pb, the concentration in stage T4 was 232.7 times higher than in T1; and for Zn, the concentration in T4 was 8.452 times higher than in T1. This study highlights the marked differences in the concentrations of selected trace metals in different malignant tumor stages. These findings indicate that some trace metals may play important roles in the pathogenesis of RCC.

The effects of prenatal intraamniotic surfactant or dexamethasone administration on lung development are comparable to changes induced by tracheal ligation in an animal model of congenital diaphragmatic hernia

BACKGROUND/PURPOSE Lung surfactant deficiency contributes to the pathophysiology of congenital diaphragmatic hernia (CDH) and the high neonatal mortality rate. Acceleration of lung surfactant system maturation by prenatal administration of hormones has been described in animal models of CDH. However, in utero tracheal ligation (TL) is the best method to accelerate lung growth and reverse the pulmonary hypoplasia associated with CDH. Although this method offers promise, its application in humans is limited. The aim of this study was to investigate a new noninvasive therapeutic strategy, that is, the prenatal intraamniotic administration of exogenous porcine surfactant or dexamethasone, and compare it with the effects of TL in an animal model of CDH. METHODS Twenty-four pregnant New Zealand rabbits underwent surgery on gestational day 24 or 25 to create CDH in 26 fetuses. Five groups of animals were studied: (1) Control, nonoperated fetuses (n=14), (2) CDH (n=6), (3) CDH plus TL (n 6), (4) CDH plus intraamniotic administration of Curosurf (40 mg; n=6), and (5) CDH plus intraamniotic infusion of dexamethasone (0.4 mg; n=8). On gestational day 30, the fetuses were delivered by cesarean section. Functional studies (lung hysteresis curves and lung distensibility), weight and volume of lungs, histopathologic and histomorphometric analysis of lungs were performed. RESULTS The authors demonstrated that the hysteresis curve of CDH animals was shifted downward in comparison with controls. The analyses of curves standardized for lung weight indicated that intraamniotic administration of surfactant or dexamethasone improved lung compliance in comparison with controls and CDH fetuses, but TL had no effect on this parameter. Lung distensibility (maximum lung volume at 32 cm of water pressure per gram of lung) was reduced by CDH, but this parameter was increased by intraamniotic administration of drugs and not by TL (P< .05). CDH decreased the weight and volume of lungs (P< .05), and these changes were reversed only by TL, which prevented the herniation of the liver from the abdomen to the thorax. Histologically, CDH lungs treated with TL or intraamniotic administration of drugs demonstrated structural patterns similar to those of controls. Histomorphometric studies proved that CDH promoted significant thickening of septa walls (P< .05), and all the therapeutic methods could reverse this alteration to control values. The alveolar number per area in control lungs, CDH, and CDH plus TL lungs were similar, but in CDH plus surfactant and CDH plus dexamethasone lungs, the decreased number per area (P< .05) demonstrated that the alveolar airspace was increased. CONCLUSION From these data the authors conclude that intraamniotic surfactant or dexamethasone administration is capable of preventing pulmonary hypoplasia in fetuses with CDH, and thus, this method may be a substitute for TL.

Bile duct ligation in neonatal rats: Is it a valid experimental model for biliary atresia studies?

Abstract:  BA is the most important disease requiring liver transplantation in children. Common BDL in rats is a classic experimental model to study biliary obstruction. The response of the neonatal animal to BDL has yet to be completely understood and few reports have focused on the behavioral differences of the liver between neonatal and adult animals. Ninety newborn Wistar rats aged six days, weighing 8.0–13.9 g, and 90 adult Wistar rats weighing 199.7–357.0 g, were submitted to BDL. After surgery, they were randomly divided and killed on the 3rd, 5th, 7th, 14th, 21st and 28th day post‐BDL. Hepatic biopsies were obtained and the following were measured: (i) semiquantification of the bile ductule proliferation and inflammatory infiltrate by HE stain, (ii) quantification of portal and periportal fibrosis with the Sirius‐red stain. Although the initial response of ductule proliferation and inflammatory infiltrate were less intense in the newborn animal, the portal and periportal fibrosis were higher when compared with adult animals (p < 0.0491). These findings may contribute to the understanding of the pathophysiology of BA.

Age related changes in the elastic fiber system of the interfoveolar ligament

In order to evaluate age related changes of the elastic fiber system in the interfoveolar ligament, we studied the deep inguinal ring from 33 male cadavers aged from stillborn to 76 years. Selective and alternated staining methods for elastic fibers were performed to differentiate oxytalan, elaunin, and mature elastic fibers. We confirmed quantitative changes of the elastic fiber system with aging. There was a significant and progressive reduction of the oxytalan fibers (responsible for tissue resistance) and a significant increment in the mature elastic and elaunin fibers (responsible for tissue elasticity). Furthermore, there were structural changes in the thickness, shortness and curling of these mature elastic fibers. These changes induced loss of the elastic fiber function and loss of the interfoveolar ligament compliance. These factors predispose individuals to the development of indirect inguinal hernias that frequently emerge in adults and aged individuals, especially above the fifth decade.