Liberato J. A. DiDio

Tibial Nerve Branching in the Tarsal Tunnel

Tarsal tunnel syndrome is an infrequent and probably underdiagnosed clinical condition. Diagnosis and treatment depend on understanding the tibial branching pattern within the tarsal tunnel. A total of 68 foot dissections were performed. Bifurcation into the medial and lateral plantar nerves occurred within the tunnel in 93% and proximal in 7%. Proximal bifurcation may predispose to tarsal tunnel syndrome, and its infrequent occurrence correlates with the infrequent clinical diagnosis. Nine different calcaneal branching patterns were noted; they provide an anatomical explanation for heel sparing. An understanding of anatomic variations should aid in providing complete surgical release and in avoiding accidental heel denervations.

Subcellular organization of the yolk syncytial-endoderm complex in the preimplantation yolk sac of the shark, Rhizoprionodon terraenovae

SummaryThe structure of the yolk syncytial-endoderm complex of the preimplantation yolk sac of the shark is examined by light- and transmission electron microscopy. The yolk syncytium is bounded by a membrane that is anchored to the plasmalemma of adjacent endoderm cells by desmosomes. Enlarged nuclei, rough endoplasmic reticulum, Golgi complexes, mitochondria, and other cellular organelles populate the syncytium. Microtubules and filamentous elements are also observed free in the syncytium. Yolk is present as pleomorphic droplets, the profiles of which are generally spherical but may be vesicular, especially at the periphery of large yolk droplets. Occasionally, large yolk droplets have a paracrystalline configuration. Small yolk droplets are modulated through the Golgi complex of the yolk syncytium, and it is suggested that acid hydrolases are added there. Small yolk droplets released from the maturing face of the Golgi complex are sequestered in membrane-limited packets. The membrane of the packets fuses with the membrane enveloping the yolk syncytium and the yolk droplets are released into the yolk syncytialendoderm interspace. Subsequently, the yolk droplets are endocytosed by the endoderm. Yolk droplets disperse and fuse to form the large irregular yolk inclusions of the endoderm. Yolk metabolites are transported out of the endoderm through the yolk sac endothelium. The yolk sac endoderm thus mediates the transfer of metabolites from the yolk mass to the extraembryonic circulation.

The aged rat pineal gland as revealed in SEM and TEM

This study utilized SEM and TEM to demonstrate and compare age-associated changes in pineal morphology of young and senile rats. Structural changes observed in this study and interpreted as age-related included (1) an Increase in the overall thickness of the connective tissue capsule with age, (2) an increase in the relative number of connective tissue cells and fibers in the aged pineals, (3) an increase in the number of striated muscle fibers in the connective tissue capsule and pineal parenchyma, (4) increased number of vacuoles, dense vesicles and dense bodies in pinealocytes, (5) mitochondria with dense cores and longitudinally arranged cristae, (6) an increase in size of cytoplasmic lipid droplets and presence of interstitial adipose lobules, (7) the presence of myelin-like figures in the stalk of the pineal gland and (8) an increase in the number and size of concretions in the aged rat pineal. In addition, the post-ganglionic sympathetic nerve fibers and vascular elements were also compared in the two age groups.

The Development of Rabbit Ovarian Follicles Following Copulation

The morphologic development of rabbit ovarian follicles was studied by means of light and electron microscopy 0, 2, 4, 6, 8, and 10 hours after copulation. The progressive changes at the apex of the follicle included extensive edema, hyperemia, and rupture of blood vessels, and then rupture of the follicular wall. Ovulation occurred when the cohesive forces in the cellular layers of the follicular apex became less than the physical forces within the follicle. Most of the morphologic changes in the follicle as it approached ovulation could be related to the effects of locally produced estrogens.

Basic and clinical hepatology

1. Segments of the liver: the anatomical basis for partial hepatectomy.- 2. Fine structure of human liver cells.- 3. Scanning electron microscopy of the mammalian liver.- 4. Freeze-fracture of hepatic fine structure under normal and experimental conditions.- 5. Morphofunctional features of cultured liver cells.- 6. Microcirculation of the liver, with special reference to the peribiliary portal system.- 7. Liver stereology.- 8. Liver physiology and biochemistry.- 9. Electron microscopy in human liver pathology.- 10. Radiology of the liver.- 11. Clinical aspects of modern hepatology.- 12. Trends and developments in hepatic surgery.

Amiodarone-associated changes in human neutrophils☆

Amiodarone and its major metabolite, desethylamiodarone, were measured in the plasma, white blood cells (WBCs) and red blood cells (RBCs) of 14 patients receiving chronic amiodarone therapy. The mean plasma concentrations (+/- standard error of the mean) of amiodarone and desethylamiodarone were 2.4 +/- 0.6 and 1.6 +/- 0.4 microgram/ml, respectively. The drug level in the WBCs was 62 +/- 12 micrograms/g protein during the early loading phase and 106 +/- 33 micrograms/g protein during maintenance phase of amiodarone therapy. Desethylamiodarone concentration in the WBCs was 42 +/- 18 and 190 +/- 33 micrograms/g protein during the loading and maintenance phases, respectively. Although a trend in WBC to plasma concentration was seen, there was no linear correlation between these levels. In 1 patient with severe neuropathy, biopsy of the nerve and muscle showed high concentrations of both amiodarone and desethylamiodarone. Although there was a decrease in tissue drug levels, proportionately high tissue:plasma drug levels were detected at the time of necropsy approximately 6.5 months after amiodarone was discontinued in this patient. Neutrophils from all patients receiving chronic amiodarone therapy showed multiple myelin-like polymorphic inclusion bodies (onionoid bodies) upon electron microscopic examination. Our observations suggest that WBC drug concentrations and electron microscopic changes may provide a means of correlating tissue concentrations and of following patients receiving chronic amiodarone therapy.

Morphological and Histochemical Study of the Submandibular Gland in Praomys (Mastomys) natalensis

The submandibular gland in female and male Praomys (Mastomys) natalensis (a South African multimammate rodent) was studied using light microscopy and techniques for the demonstration of carbohydrates. Hematoxylin and eosin stain revealed the presence of a single secreting component that gave a strongly positive PAS reaction. Limiting elements of the granular tubules gave a weakly positive PAS reaction. Acidic glycoproteins were evidenced only in granules of the acinar component.

Myocardial bridges over coronary arteries in Cercopithecus.

The presence of myocardial bridges over the coronary arteries has been studied in 29 monkey (Cercopithecus aethiops) hearts. The great resemblance between the Cercopithecus subepicardial arterial net with the corresponding one in humans has been revealed. There is a high incidence (83%) of myocardial bridges only over the ventricular branches of both coronary arteries. Myocardial bridges are usually (90%) located over the left coronary artery branches, and the left anterior interventricular branch is the most frequently (69%) overbridged vessel. The bridges are always single over the vessel examined and their length varies from 0.5 mm to 31.6 mm. No statistically significant sexual difference in myocardial bridges distribution is reported.

Morphology of the swine ileum terminale.

The morphology of the terminal ileum was studied in 33 male adult pigs of unknown breed. The ileum ended in the cecocolic junction at an acute angle to the cecum. The terminal ileum displayed a cylindrical form (63.6% +/- 8.4 of the cases) more frequently than an ampullary (21.2% +/- 7.1) and/or an infundibular form (15.2% +/- 6.2). The ampullary form is not related to the quadrupedal position of the animal, but is related to the functional phase of the intestine at the time of death. In the mucous tunica of the terminal ileum, longitudinal folds and aggregated lymphoid nodules appeared concentrated along the antimesenteric border.

Basic, clinical, and surgical nephrology

1. Segments of the Kidney: the Anatomical Basis for Nephrosegmentectomy.- 2. Anatomical and Embryological Aspects of the Renal Venous Drainage.- 3. Embryogenesis of the Kidney.- 4. Microscopic Structure of the Kidney.- 5. Renal Vasculature as Observed by SEM of Vascular Casts. Basic, Architecture, Development and Aging of Glomerular Capillary Beds.- 6. Subcellular Structure of the Renal Glomerulus.- 7. Recent Research on Some Aspects of Proximal Tubular Transport Phenomena.- 8. Immunologic Aspects of Renal Transplantation.- 9. Current Concepts of Glomerular Diseases.- 10. Renal Vascular Diseases: Their Relationship to Hypertension.- 11. Renal Biopsies: Glomerular Subcellular Features.- 12. Dialysis.- 13. Radiological Modalities in the Examination of the Kidney.- 14. Clinical Aspects of Renal Insufficiency Induced by Drugs and Hepatic Disease.- 15. Surgical Aspects of Nephrology.