Innervation patterns of sea otter (Enhydra lutris) mystacial follicle-sinus complexes

Sea otters (Enhydra lutris) are the most recent group of mammals to return to the sea, and may exemplify divergent somatosensory tactile systems among mammals. Therefore, we quantified the mystacial vibrissal array of sea otters and histologically processed follicle-sinus complexes (F - SCs) to test the hypotheses that the number of myelinated axons per F - SC is greater than that found for terrestrial mammalian vibrissae and that their organization and microstructure converge with those of pinniped vibrissae. A mean of 120.5 vibrissae were arranged rostrally on a broad, blunt muzzle in 7–8 rows and 9–13 columns. The F-SCs of sea otters are tripartite in their organization and similar in microstructure to pinnipeds rather than terrestrial species. Each F-SC was innervated by a mean 1339 ± 408.3 axons. Innervation to the entire mystacial vibrissal array was estimated at 161,313 axons. Our data support the hypothesis that the disproportionate expansion of the coronal gyrus in somatosensory cortex of sea otters is related to the high innervation investment of the mystacial vibrissal array, and that quantifying innervation investment is a good proxy for tactile sensitivity. We predict that the tactile performance of sea otter mystacial vibrissae is comparable to that of harbor seals, sea lions and walruses

Scar-like lesion on dorsal nose (cellular neurothekeoma)

Neurothekeomas are tumors of neural differentiation and of unknown origin that occur in females at the 2nd and 3rd decades of life. They usually affect the face with an unspecific clinical aspect. The histological features include cellular or mixoid differentiation and immunohistochemistry can be positive for protein s-100, vimentin and epithelilal membrane antigen (EMA)

Tumors of the urinary bladder /

Includes bibliographical references and index.Mode of access: Internet

Atlas of tumor pathology.

Fasc. 39: Index.Issued under the auspices of the Subcommittee on Oncology of the Committee on Pathology of the Division of Medical Sciences of the National Academy of Sciences--National Research Council.Includes bibliographies.Mode of access: Internet

Tumors of the lymph nodes and spleen /

Includes bibliographical references and index.Mode of access: Internet

Pulmonary arteriopathy and idiopathic pulmonary arterial hypertension in six dogs

Pulmonary arteriopathy (PA) is the pathologic hallmark in human medicine of diffuse constrictive (medial and intimal remodeling) or multifocal complex (plexiform and dilatative lesions) arterial lesions, or both, that lead to irreversible obliteration of the arterial lumen. Clinically, PA leads to pulmonary arterial hypertension (PAH), of which idiopathic (IPAH) is one of the 5 subsets, and ultimately, to right-sided heart failure (RHF). Clinical and pathologic findings from 6 dogs with diagnosis of IPAH and PA were reviewed. These dogs were of various pure (5/6, 83%) and mixed (1/6, 17%) breeding, 5 months to 9 years (mean 5.2 years) old, and predominantly female (4/6, 67%) and reproductively intact (4/6, 67%). Doppler echocardiography (n 5 5) indicated increased pulmonary arterial pressures during systole (70–135 mm Hg, mean 98 mm Hg) and diastole (35–80 mm Hg, mean 58 mm Hg). All 6 dogs had right ventricular pressure overload, right ventricular eccentric hypertrophy, and RHF. Histologic examination confirmed the clinical diagnosis of IPAH in all dogs, revealing PA characterized by 1 of the 4 main human histologic subsets: 1) isolated medial hypertrophy (1/6, 17%); 2) medial hypertrophy-intimal thickening without the plexiform lesion (1/6, 17%); 3) medial hypertrophyintimal thickening concurrent with the plexiform lesion, which often was regionally clustered and situated near branching points of the respiratory artery, the poststenotic dilatation lesion, and vasculitis (4/6, 66%); and 4) isolated arteritis (1/6, 17%). Ancillary lesions similar to those in humans also complicated the PA (5/6, 83%). The complex lesions and ancillary exudative alveolitis seemed to be important indicators of severe, likely rapidly progressive and fatal, IPAH