Biomedical subjects
Publications and source records attributed to V Ho.
Isolated unilateral fractures of the zygomatic arch are uncommon. Isolated bilateral fractures of the zygomatic arches are even more rare. Indeed a search of the literature failed to find any previous report of this fracture pattern.
Granulocytic sarcoma is a rare tumor composed of granulocytic precursor cells. The most common sites of involvement include the bones, soft tissue, lymph nodes and skin. Granulocytic sarcoma usually develops as a delayed manifestation of the disease process in patients with known acute myelogenous leukemia. To our knowledge we report the first case of renal granulocytic sarcoma presenting as the first sign of acute myelogenous leukemia. Computerized tomography and magnetic resonance imaging revealed diffuse nonspecific global tumor infiltration of the kidney and ureter. Renal granulocytic sarcoma was diagnosed on open renal biopsy and acute myelogenous leukemia on bone marrow biopsy. There has been partial response to combination chemotherapy. Renal granulocytic sarcoma may diffusely involve the kidney as the only manifestation of acute myelogenous leukemia and it should be included in the differential diagnosis of the many disease entities with global renal involvement since initial treatment is combination chemotherapy.
BACKGROUND: Topical diphenylcyclopropenone (DPCP) and minoxidil have been used in the treatment of alopecia areata with variable results. OBJECTIVE: This study was designed to evaluate the efficacy of DPCP alone or in combination with topical 5% minoxidil for the treatment of chronic severe alopecia areata. The effect of therapy on cutaneous T-cell and Langerhans cell subpopulations and intercellular adhesion molecule-1 (ICAM-1) expression was also examined. METHODS: Fifteen patients with chronic (more than 2 years), severe (more than 50% scalp involvement) alopecia areata participated in a 24-week trial. Half of the scalp was treated with DPCP once weekly and with either 5% minoxidil solution or a vehicle solution twice daily in a randomized double-blind design. Skin biopsy specimens from each half of the scalp were obtained before therapy and after 12 and 24 weeks of therapy for histologic and immunophenotypic analysis. RESULTS: Thirteen patients completed the study. Five of 13 patients (38%) showed marked regrowth of coarse terminal hair after 24 weeks of treatment with DPCP. The addition of topical 5% minoxidil did not produce any significant clinical benefit in this 24-week trial. Immunophenotypic analysis showed no differences between responders and nonresponders at baseline. During treatment, Leu-4, Leu-2, Leu-3, and keratinocyte ICAM-1 expression were significantly reduced in biopsy specimens of responders versus nonresponders. CONCLUSION: DPCP treatment showed a 38% success rate in producing cosmetically acceptable regrowth in patients with chronic severe alopecia areata.
A case which was reported in the national press, is described where a fatality occurred as a result of an acute dentoalveolar abscess, and the subsequent development of septicaemia with Disseminated Intravascular Coagulation (DIC). A review of the English literature shows that there are no reported cases of death associated with acute dentoalveolar infection and DIC.
Data on the use of oral cyclosporin A (CyA; Sandimmun) therapy for severe adult atopic dermatitis have accumulated since 1987. Details of over 200 adult patients who have received short-term CyA were presented at an international workshop in April 1993. Eighty-six of these patients had participated in three randomized, double-blind, placebo-controlled studies in which CyA was given for 6-8 weeks. The efficacy and safety of short-term CyA treatment in atopic dermatitis is established, provided that appropriate guidelines are observed. Evidence to date suggests that atopic dermatitis patients are no more prone to toxicity than patients with psoriasis, in whom more detailed and longer-term data are available. Early data also suggest that long-term CyA may be effective in atopic dermatitis, but there is concern regarding long-term safety, as experience is still limited. Careful monitoring of all CyA-treated patients is therefore mandatory. CyA should only be used under the direct and regular supervision of a hospital-based dermatologist who is knowledgeable in the use of cyclosporin A, and experienced in the management of severe skin disease and in the use of potentially toxic drugs.
BACKGROUND: Patients who survive retinoblastoma (RB) are at risk for having second nonocular tumors, usually osteosarcomas, which often are fatal. Such patients almost always have bilateral RB. METHODS: This article reports a woman who, at the age of 1 year had been cured of a unilateral RB by radiation therapy and enucleation. Eighteen years later, she had a sinonasal small cell tumor that rapidly recurred and proved fatal 2 months after surgical debulking. The tumor was studied by immunohistochemistry and electron microscopic (EM) examination. RESULTS: It showed diffuse neuron-specific enolase staining, focal weak staining for chromogranin, synaptophysin, and Leu-7 monoclonal antibodies in paraffin-embedded, B5-fixed tissue (Great Lakes Diagnostics, Troy, MI). EM study showed an undifferentiated primitive neuroectodermal tumor with many polyribosomes, simple cell junctions, few microtubules, and rare dense core granules. CONCLUSIONS: The combined immunohistochemical, ultrastructural, and clinical features of the tumor were interpreted as a sinonasal primitive neuroectodermal tumor with early neuronal differentiation. The tumor was pathologically indistinguishable from poorly differentiated olfactory neuroblastoma (ONB) and Ewing sarcoma.
Sialolithiasis of minor salivary glands is generally considered to be extremely rare. Reports of seven cases are presented. A review of the literature suggests that the condition is not as uncommon as previously considered, and that definitive histopathological diagnosis of lip swellings should be obtained due to the incidence of labial pleomorphic adenoma and the possibility of the clinical misdiagnosis with sialolithiasis.
Major increases have occurred in the incidence of basal cell carcinoma and squamous cell carcinoma of the skin, as well as in cutaneous malignant melanoma during the period 1973 through 1987 in British Columbia. The greatest increases in basal and squamous cell carcinomas are on the head and neck. This indicates that exposure to sunlight is the major causative factor. The greatest increase in melanoma is on the trunk in men and on the lower limbs in women. The dramatic increases in nonmelanoma skin cancers in British Columbia, a relatively low sunlight area, suggest that major prevention programs are needed in areas that are not considered "sunspots."
UM4D4 (CDw60), the surface molecule of a novel antigen-independent T-cell activation pathway, was found to be highly expressed on lesional psoriatic T cells. To examine whether UM4D4 represents a T-cell activation pathway for psoriatic T cells, a T-cell line was initiated from an acute skin lesion and cloned by limiting dilution. Clonality was verified by analysis of T-cell receptor gene rearrangement. All T-cell clones tested, whether CD4+2H4+CD8-, CD4+2H4-CD8-, or CD4-CD8+CD11b-, expressed UM4D4 and were activated by the monoclonal antibody anti-UM4D4. Lesional psoriatic T-cell clones were heterogeneous in the degree of anti-UM4D4-induced proliferation and in their production of IL-2 and gamma-interferon. Lymphokines released by anti-UM4D4 activation were capable of inducing ICAM-1 and HLA-DR expression on cultured normal keratinocytes. Thus, the high expression of UM4D4 on T-cells in psoriatic skin provides an alternative mechanism for T-cell activation that may be operative in the psoriatic lesional milieu. Indeed, activation of lesional T-cells through the UM4D4 molecule resulted in release of lymphokines that directly induced keratinocytes to express a phenotype displayed in psoriatic skin lesions.
Changes in the size of the glottis with bronchoconstriction were assessed in six normal subjects following inhalation of histamine or methacholine. Measurements were made during both tidal breathing and panting at 2-3 Hz. The midexpiratory size of the glottis was decreased by a mean of 8% during bronchoconstriction compared with control during tidal breathing. Changes in midinspiratory size were inconsistent. During panting, the glottic size was unchanged from inspiration to expiration but decreased in 7 of 15 studies during bronchoconstriction. The decreases in expiratory size of the glottis during quiet breathing would lead to an elevated laryngeal resistance coupled with an increased lower airway resistance. Although this seems to be a paradoxical laryngeal response, it may contribute to maintaining hyperinflation during bronchoconstriction, thereby effectively enlarging the lower airways.
A 34-year-old woman with Factor XI deficiency presented with rapidly progressive quadriplegia following a 1-week prodrome of cervical pain. At operation, a spontaneous hematomyelia was evacuated from the C4-6 vertebral level. The pathophysiology of spontaneous hematomyelia is discussed.
CT examination of the central nervous system was performed in 19 patients with acquired immunodeficiency syndrome (AIDS). Eighteen patients were homosexuals, and five drug abusers. Parenchymal and meningeal inflammations were seen in patients with intracranial manifestations of the disease. The most common demonstrable lesion in the parenchyma was toxoplasmosis, which produced ring enhancement, solid enhancement, and nonenhancing focal edema. The most common meningeal inflammation was cryptococcosis, which was diagnosed by examination of the cerebrospinal fluid and did not show specific CT changes. It is concluded that toxoplasmosis and cryptococcosis should be the first diagnostic consideration in patients with neurologic findings who have a history of homosexuality and/or intravenous drug abuse and previous unusual infections or anergy. A delayed contrast scan, single or double dose, appears to be the most accurate method of outlining the total extent of disease thereby helping to locate the best biopsy site for pretreatment diagnosis. Empirical institution of toxoplasmosis therapy is recommended in those cases in which CT findings are consistent with toxoplasmosis and the biopsy shows only nonspecific encephalitis. A biopsy of every parenchymal lesion is not considered necessary.
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The acquired immune deficiency syndrome (AIDS) is a recently described T-cell deficiency predisposing patients to a spectrum of opportunistic infections. Kaposi's sarcoma, and other neoplasms. It appears primarily among homosexual males and intravenous drug abusers, but is now being observed in other groups as well. The authors describe six adult patients with AIDS who developed intracranial toxoplasmosis. In four patients, diagnosis was made by brain biopsy, and in one by serology. These patients received a 90-day course of therapy with sulfadiazine, pyrimethamine, or both when tolerated, and improved neurologically. In one patient, the brain biopsy was nondiagnostic and the organism was identified at autopsy. On computerized tomographic and pathological follow-up studies the organism appeared to be eradicated by therapy. Early aggressive diagnostic study and prompt institution of therapy are imperative for reversal of neurological deficits. Despite cure of toxoplasmosis, the prognosis in patients with AIDS is poor; the mortality in this series was 67%. Isolation precautions should be taken by those caring for such patients.
Spinal cord injury consistently evokes a transient 3- to 4-minute rise is systemic pressure, followed by prolonged hypotension. Because the role of the sympathetic nervous system in these blood pressure changes is not clear, the pressure responses were studied using systematic ablation of the peripheral sympathetic nervous system. In total, 24 cats were subjected to bilateral thoracic sympathectomy, adrenalectomy, splanchnicectomy, combinations of the preceding, sham operation, or no treatment. Either 3 or 24 hours after the ablations, the blood pressure responses were evoked by 400 gm-cm contusions of the thoracic cord. Although neither thoracic sympathectomy nor adrenalectomy alone abolished the hypertensive phase, the combination of the two procedures did. This suggests that both the thoracic sympathetic ganglia and the adrenal glands participate in the pressor response. Thoracic sympathectomy affected primarily the early part, whereas adrenalectomy diminished the later part of the hypertensive response. This correlates with the function of the former being neurally and the latter being humorally mediated. None of the sympathetic lesions consistently affected the hypotensive phase. Spinal contusion injury produces widespread sympathetic activation, mediating the hypertensive changes.
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