The effect of temporal and force changes on the patterning of sequential movements.

This article examines the programming of relatively long sequences of action with the control of sequential movements being effected through the use of a tapping task involving a sequence of five taps. Subjects were required to tap with their right hand at rates of 150, 200, and 250 ms. There were two conditions, with subjects being required either to increase, in condition 1, or to decrease, in condition 2, the force at one of the five tap positions (all five tap positions were examined), then return to the previous force level. Changes in timing resulting from variations in the force characteristics have previously been discussed in terms of changes in the organizational time required (Semjen, Garcia-Colera, & Requin, 1984). The current study breaks the intertap interval down into two separate components: the contact interval (finger in contact with the key) and the non-contact interval (interval preceding the tap). Although changes in the non-contact interval could be explained in terms of changes in the organizational time required, changes in the contact interval appeared to be a result of the mechanical changes in force.

Vibrio cholerae non-O1 infection presenting as localized cellulitis.

Vibrio cholerae non-O1 characteristically causes gastrointestinal illness but can occasionally be responsible for extra-intestinal infections. The authors report an unusual case of a man presenting with extensive cellulitis that did not improve with conventional antimicrobial therapy. Vibrio cholerae non-O1 was later isolated from a cutaneous bulla. Although he had severe hepatic cirrhosis, the infection remained confined to the cutaneous tissues and he was never bacteremic. He improved dramatically with surgical debridement in conjunction with antibiotics. It is important to consider Vibrio cholerae non-O1 as a cause of cellulitis, especially in endemic areas.

Aschoff bodies of rheumatic carditis are granulomatous lesions of histiocytic origin.

The histogenesis of the Aschoff body of rheumatic carditis is controversial. Proliferative Aschoff bodies in heart sections from 6 patients with acute rheumatic heart disease were tested by avidin-biotin peroxidase labeling methods for the presence of desmin, muscle-specific actin, S-100, neurofilament, leukocyte common antigen, receptor for Ulex europeus I lectin, Factor VIII-related antigen, vimentin, alpha 1-antichymotrypsin, and myeloid/histiocyte antigen. Lack of Aschoff body labeling for desmin and muscle-specific actin, S-100 and neurofilament, and Ulex europeus I and Factor VIII-related antigen is not consistent with histogenesis from smooth or striated cardiac muscle, nerve or nerve sheath, and lymphatic or vascular endothelium, respectively. Strong labeling of Aschoff body cells for vimentin is evidence for a mesenchymal origin, and labeling for myeloid/histiocyte antigen is consistent with a histiocytic origin. Furthermore, weak, variable labeling of Aschoff body cells for leukocyte common antigen suggests that at least some Aschoff body cells were originally derived from blood-borne monocytes. Both multinucleated Aschoff cells and "owl's eye," Anitschkow cells label identically, suggesting a common origin. Alpha 1-Antichymotrypsin, a widely utilized marker of histiocytes, was unexpectedly negative. Perhaps histiocytes that form Aschoff bodies do not express this lysosomal enzyme. Aschoff bodies appear to be a unique and distinctive form of granuloma.

Nontuberculous mycobacterial skin infection resembling lepromatous leprosy.

A leg ulcer in a 52-year-old renal transplant patient yielded foamy histiocytes containing acid-fast bacilli subsequently identified as a Runyon group III Mycobacterium. Skin infection with these organisms is unusual, and the histologic appearance in this case suggested lepromatous leprosy.

Spindle cell mucoepidermoid carcinoma of submandibular gland.

A malignant tumor of the submandibular gland was found to consist predominately of spindle cell elements that initially suggested a primary sarcoma. Further examination revealed that the spindled malignant cells were derived from a high-grade mucoepidermoid carcinoma.

Large Cryptococcus neoformans isolated from brain abscess.

Cryptococcus neoformans yeast cells 40 to 60 micron in diameter were seen in an India ink preparation made from a human brain abscess specimen. In culture at 25 degrees C, uniform 5-micron-diameter yeast cells were produced. Inoculation into mice produced yeast cells up to 40 micron in diameter, and brain heart infusion broth culture at 35 degrees C produced yeast cells about 25 micron in diameter. A relationship of yeast cell diameter to incubation temperature is suggested.

Intramyofiber metastasis in skeletal muscle.

Malignant epithelial cells were noted within the sarcolemmal sheath of skeletal muscle fibers in a case of recurrent laryngeal carcinoma. Literature is reviewed to evaluate the diagnostic and prognostic significance of this rare intramyofiber skeletal metastasis by cancer cells.

Mycobacterium terrae tenosynovitis.

A 72-year-old man was admitted with tenosynovitis of the left forearm and hand. Histopathologic examination of the excised tissue showed noncaseating granulomas. Mycobacterial culture produced Mycobacterium terrae complex. M. terrae infection of any site is rare. Analysis of four documented cases and our present case indicates that this organism causes infection in the forearm and hand after probable direct inoculation. It has not disseminated systemically from the site of local infection and may infect otherwise healthy hosts.

Myoid hamartomas of the breast.

Tumors containing smooth muscle are rare in the breast. A myoepithelial origin for the myoid component of such lesions was postulated in previous reports. Myoepithelial hyperplasia has long been recognized as a common component of some breast lesions, including sclerosing adenosis, papillomas, and fibroadenomas. Three breast tumors composed of variable admixtures of adipose tissue, fibrous tissue, and smooth muscle are described. The authors postulate that the myoid component of two of the three lesions may have arisen in a milieu of myoepithelial hyperplasia. The origin of the myoid component in the third case is not clearly defined.

Giant polypoid basal cell carcinoma.

A giant polypoid basal cell carcinoma occurring in the back of a 64-year-old man is reported. Three other such cases from the English literature are reviewed.

Hemangioblastomas with cystic stromal cell nuclei.

Clearing of stromal cell nuclei were found in two of a series of nine cases of hemangioblastoma. The contents of the clear zones were often positive for lipoprotein by immunoperoxidase staining which suggested that the contents originated from the cytoplasm. Cytoplasmic invagination was not observed but is probable; some vacuoles had a "bubbly" appearance similar to the lipid-laden cytoplasm. The finding of these variations in two of nine cases suggests that cystic change in stromal cell nuclei may not be uncommon in hemangioblastomas.

Bronchogenic sarcomatoid squamous cell carcinoma with osteoclast-like giant cells.

A 60-year-old man developed a widely metastatic spindle cell neoplasm with admixed osteoclast-like giant cells indistinguishable from malignant giant cell tumor of soft parts. Autopsy revealed a bronchogenic sarcomatoid squamous cell carcinoma that was the primary source of the sarcomatoid metastases. The osteoclast-like giant cells in the metastatic lesions were negative for lysozyme on immunoperoxidase staining. This finding suggested that the multinucleated giant cells were not formed as a cellular response to hemorrhage or to cellular debris induced by the tumor. Extraosseous neoplasms with osteoclast-like giant cells are rare neoplasms that may occur in a variety of organs. This case is the second reported case of a primary neoplasm in the lung that contained these osteoclast-like giant cells. These tumors may cause considerable diagnostic confusion.

Intranasal encephalocele masking as a nasal polyp in an adult patient.

Intranasal encephaloceles are rarely seen in adult patients. These lesions may be mistaken for nasal polyps. A 36-year-old woman died after the removal of an intranasal encephalocele during a routine polypectomy. The possibility of an intranasal encephalocele must be considered when examining adult patients with nasal polyps.

Fatal acute hyperparathyroidism and parathyroid carcinoma.

A 43-year-old man with parathyroid carcinoma died with hypercalcemia before a definitive diagnosis was made. The condition of patients with hypercalcemia may deteriorate rapidly, and delays in treatment may be fatal. Metastatic growth, not mitotic activity, is the best criterion for the pathologic diagnosis of parathyroid carcinoma.