Morphometric study of extra-hepatic biliary pathways: study in human corpses / Estudio morfométrico de las vías biliares extrahepáticas: estudio en cadáveres humanos

SUMMARY: Adverse events (AE) contribute significantly to postoperative morbidities and comorbidities. Many AEs occur due to a lack of anatomical knowledge and its variants. Latrogenic bile duct injuries, for instance, represent a serious surgical complication of laparoscopic cholecystectomy. Anatomical knowledge for the identification and adequate drainage of all ducts is relevant and fundamental in order to avoid future errors. The objective of the study was to morphometrically analyze the bile ducts in adult human corpses. 13 livers were extracted from adult human corpses to obtain the ducts: choledochal, common hepatic and cystic. After morphological analysis, duct measurements (length and diameter) were continued using a digital caliper. The data obtained were tabulated in SPSS 21 program, performing descriptive analysis with mean and standard deviation. The averages of bile ducts were 61.05 (± 16.43) mm in length and 3.86 (± 0.72) mm in diameter. The cystic duct length and diameter averages were 33.59 (± 12.29) mm and 3.40 (± 0.79) mm, respectively. The common hepatic ducts had an average of 30.02 (± 7.19) mm in length and 3.74 (± 1.18) mm in diameter. The analyzed samples presented different values ?? from those already described in the literature, where the length of the cystic ducts was greater, while the length of the common hepatic ducts was numerically smaller. This work is very significant, as the morphometric variability of the bile ducts allows for varying morphological situations that can compromise the hepatobiliar physiology.

RESUMEN: Los eventos adversos (EA) contribuyen significativamente a las morbilidades y comorbilidades postoperatorias. Muchos EA se deben a la falta de conocimiento de la anatomía y sus variaciones. Por ejemplo, las lesiones iatrogénicas de las vías biliares representan una complicación quirúrgica grave de la colecistectomía laparoscópica. El conocimiento anatómico para la identificación y drenaje adecuado de todos los conductos es relevante y fundamental para evitar futuros errores. El objetivo del estudio fue analizar morfométricamente las vías biliares en cadáveres humanos adultos. Se extrajeron 13 hígados de cadáveres humanos adultos y se retiraron los conductos: colédoco, hepático común y cístico. Después del análisis morfológico, se continuó con las mediciones de los conductos (longitud y diámetro) utilizando un calibrador digital. Los datos fueron tabulados en el programa SPSS 21, mediante análisis descriptivos con media y desviación estándar. Los promedios de las vías biliares fueron de 61,05 (± 16,43) mm de longitud y 3,86 (± 0,72) mm de diámetro. Los promedios de longitud y diámetro del conducto cístico fueron 33,59 (± 12,29) mm y 3,40 (± 0,79) mm, respectivamente. Los conductos hepáticos comunes tenían un promedio de 30,02 (± 7,19) mm de longitud y 3,74 (± 1,18) mm de diámetro. Las muestras analizadas presentaron valores diferentes a los ya descritos en la literatura, donde la longitud de los conductos císticos era mayor, mientras que la longitud de los conductos hepáticos comunes fue numéricamente menor. Este trabajo es significativo, debido a que la variabilidad morfométrica de las vías biliares y permite identificar situaciones morfológicas que pueden comprometer la fisiología hapatobiliar.

Immunohistochemistry and ultrastructural characteristics of nerve endings in the oral mucosa of rat.

The sensory nerve endings of the rat tongue, cheek and palate were studied using immunohistochemical staining and transmission electron microscopy analysis. The specimens were fixed in modified Karnovsky solution and embedded in Spurr resin. Substance P, calcitonin gene-related peptide (CGRP)- and protein gene product 9.5 (PGP b9.5)-containing nerve fibers in the rat tongue, cheek and palate were examined by electronic microscopical analysis and immunohistochemical localization. These fibers run very close to the basal lamina of the epithelium and extend into the filliform and fungiform papillae. Numerous plexiform fibers immunoreactive for substance P, CGRP and PGP 9.5 were found in the connective tissue of mucosa. Electron microscopic observations showed clearly immunostained nerve fibers, which are located very close to the basal lamina of epithelial cells. Some electron-dense granules may be observed in the axoplasms of both substance P and CGRP immunoreactive fibers. Several lamellar corpuscles into the subepithelial connective tissue papillae, Merkel corpuscles and numerous thin unmyelinated and myelinated axons were observed. The terminal axons revealed numerous mitochondria, neurofilaments, microtubules and clear vesicles in the base of axoplasmic protrusions. The lamellar cells showed caveolae and interlamelar spaces filled by amorphous substance. Between the lamellar cells and axoplasmic membrane, and in the adjacent lamellae region, desmosome-type junctions were observed. The quantitative and morphometric analysis showed nerve endings with an average area of 4.83 ± 3.4 µm(2) and 19.4 internal mitochondria in this site and the organized corpuscles with an average area of 79.24 ± 27.24 µm(2) and 24.23 internal mitochondria in this place. All the structures observed are involved in the transmission of pain and mechanoreceptors stimulus of these oral mucosae.

Ultrastructural features of the myotendinous junction of the sternomastoid muscle in Wistar rats: from newborn to aging.

The myotendinous junction (MTJ) is a major area for transmitting force from the skeletal muscle system and acts in joint position and stabilization. This study aimed to use transmission electron microscopy to describe the ultrastructural features of the MTJ of the sternomastoid muscle in Wistar rats from newborn to formation during adulthood and possible changes with aging. Ultrastructural features of the MTJ from the newborn group revealed pattern during development with interactions between muscle cells and extracellular matrix elements with thin folds in the sarcolemma and high cellular activity evidenced through numerous oval mitochondria groupings. The adult group had classical morphological features of the MTJ, with folds in the sarcolemma forming long projections called "finger-like processes" and sarcoplasmic invaginations. Sarcomeres were aligned in series, showing mitochondria near the Z line in groupings between collagen fiber bundles. The old group had altered "finger-like processes," thickened in both levels of sarcoplasmic invaginations and in central connections with the lateral junctions. We conclude that the MTJ undergoes intense activity from newborn to its formation during adulthood. With increasing age, changes to the MTJ were observed in the shapes of the invaginations and "finger-like processes" due to hypoactivity, potentially compromising force transmission and joint stability.