Biomedical subjects
Publications and source records attributed to L Kaufman.
Live rats were imaged by nuclear magnetic resonance (NMR). These images demonstrated fine detail and high object contrast. Motion artifacts are not apparent in 4-minute images, and major blood vessels are demonstrated as regions of low signal intensity because of blood flow. Selective contrast enhancement is possible by varying NMR imager accumulation parameters.
A nuclear magnetic resonance (NMR) imager with a 6.5-cm aperture is described. Spatial resolution is 0.47 X 2.0 mm with a slice thickness of 8.4 mm. Contrast resolution is 3% for a 4-minute image. Because of the excellent spatial resolution and high contrast between soft tissues, the images provide a great deal of detail and reconstruction artifacts due to motion are avoided. Blood flow can be observed, and selected enhancement of lesions thorough the modification of software-controlled operational parameters is demonstrated.
Antigen-rich mycelial extract (ME) and fractions of Aspergillus fumigatus were compared with culture filtrates of A. fumigatus. A. flavus, and A. niger for their abilities to detect antibody in serums from patients with confirmed aspergillosis caused by these fungi. In double immunodiffusion tests, homologous antigen preparations were more effective than heterologous preparations in detecting precipitins. Mycelial extract of A. fumigatus was more effective than A. fumigatus culture filtrate in detecting antibody in serums from patients with disease caused by A. flavus and A. niger. It did not, however, detect antibody in the serums from approximately half of the patients with heterologous infections.
An outbreak of acute histoplasmosis occurred in northern Louisiana in September 1977. All six men who cleared a field of bamboo cane known to be a blackbird roosting site were affected. All had clinical and roentgenographic findings of acute pulmonary histoplasmosis, and all recovered. Seroconversion or fourfold rise in antibody to Histoplasma capsulatum yeast--or mycelial-form antigens were demonstrated in five. Immunodiffusion testing showed that all six patients developed H capsulatum M bands, and two developed H bands specific for active infection. The H capsulatum was isolated from the soil in the cane field. This is the first report of an outbreak of histoplasmosis in Louisiana and the first known isolation of H capsulatum from Louisiana soil.
Brain abscesses caused by Entamoeba histolytica were treated in two residents of New Jersey, neither of whom had traveled beyond the eastern United States. The diagnosis in Case 1 was confirmed by the presence of ameba in both brain and pituitary abscesses. An elevated indirect hemagglutination (IHA) titer of 1:4096 and response to specific treatment with metronidazole and chloroquin were the criteria for diagnosis in Case 2. The computerized tomographic appearance of an amebic abscess is that of a rapidly progressive lesion without reaction in the adjacent brain. Of the seven reported cures, all of the patients received appropriate chemotherapy. Five of the seven were operated upon.
Sixteen sera from 17 dogs with blastomycosis produced a precipitin band identical with the diagnostically significant precipitin A band formed by a Blastomyces dermatitidis reference antiserum and a soluble B dermatitidis yeast-form antigen in the agar-gel immunodiffusion test (94% sensitivity). The other serum from a dog with histopathologic demonstration of B dermatitidis in pulmonic tissues produced an unrelated precipitin band. Sixteen of the 17 diagnoses made by the detection of precipitin A were confirmed by isolation and culture of B dermatitidis or by histopathologic demonstration of the pathogen. Three cases were confirmed by cultural isolation only, 10 by histopathologic demonstration only, and 3 by both. In three other dogs given amphotericin B, there were demonstrable changes in serum precipitin A reactions.
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Sera from 71 patients with culturally proven nocardiosis were tested for precipitins against a pool of Nocardia asteroides and N. brasiliensis culture filtrates and against antigens from the supernatant of homogenized N. asteroides cells. A human nocardiosis case serum was used as a reference. Sera from 56 of the 71 cases were reactive with either the culture filtrate antigen, the homogenate antigen, or both antigens, resulting in an overall sensitivity of 79%. Sera from 35 of the patients (49%) were positive with the homogenate antigens, and 28 (39%) showed bands of identity with the reference serum. Sera from 50 nocardiosis cases (70%) were positive with the pooled culture filtrate antigens, and 29 (41%) produced bands of identity with the reference serum. Of 89 sera from patients with various systemic mycotic diseases, tuberculosis, or actinomycosis, 24 (27%) were positive with the nocardial homogenate antigens and 4 (4.5%) showed precipitin bands of identity. Thirty-five of the 89 sera (42%) were positive with the nocardial culture filtrate antigens, and 6 (6.7%) showed bands of identity. The majority of sera demonstrating false-positive reactions were from tuberculosis and actinomycosis cases. One of seven sera from well individuals produced a precipitin band with the culture filtrate antigen, but this was not a band of identity with reference serum. These antigens did not distinguish antibodies from patients with N. asteroides, N. brasiliensis, or N. cavia infections.
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1 The circulatory effects of labetalol have been studied in 88 patients undergoing plastic surgery, 8 patients with carcinoma of the breast, 10 with carcinoma in the head and neck, and in 2 patients with phaeochromocytoma, each anaesthetized twice. 2 The use of labetalol intravenously produced hypotension and a bloodless operating field in patients undergoing plastic surgery and in those undergoing radical surgery for the removal of carcinoma. 3 Two patients with phaeochromocytoma pre-treated with oral labetalol before anaesthesia, had well controlled BPs and heart rates during surgery, although in one instance additional intravenous labetalol was required. 4 Pre-operative preparation of patients with phaeochromocytoma with labetalol seems to be simpler and safer than previous techniques involving drugs with separate alpha- and beta-adrenoceptor-blocking effects.
In December 1975 and January and February 1976, an epidemic of cutaneous sporotrichosis occurred in Mississippi among forestry workers and other persons exposed to sphagnum moss used in packing pine seedlings. Seventeen cases were identified, 15 of which were from patients who had been exposed to sphagnum moss from a single source. Attack rates were significantly higher among workers exposed to this moss than among those not exposed. Sporothrix schenckii was cultured from the implicated batch of sphagnum moss but not from other batches. The source of contamination of the sphagnum moss that caused this epidemic and sphagnum moss associated with similar epidemics is unknown. One worker without cutaneous sporotrichosis may have had asymptomatic pulmonary sporotrichosis.
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Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Cadmium telluride (CdTe) presents a set of extremely attractive features as an X-ray detector for computer assisted tomography (CAT). It is stable and easily handled; has a high detection efficiency and very efficient conversion of energy to charge; and permits a high element density in a compact configuration. Unfortunately, effects due to "polarization," "tailing," high and variable leakage currents, and long "memory" are incompatible with the needs of CAT instrumentation. Pulse-processing techniques have allowed us to eliminate these problems in positive-sensitive detectors, thus opening the way for utilization of CdTe in CAT.
An antigen analysis with filtrate and homogenate precipitinogens of single isolates of the zygomycetes Absidia corymbifera, Mucor pusillus, Rhizopus arrhizus, and Rhizopus oryzae demonstrated the presence of common antigens among the three genera as well as antigens which permit their differentiation. Selected homogenate antigens were valuable in developing a diagnostic immunodiffusion (ID) test for systemic zygomycosis. When sera from 43 patients with various proven mycoses other than zygomycosis were tested against each of the antigens, none formed precipitin bands identical to those formed by A. cormybifera, M. pusillus, and the Rhizopus spp. rabbit reference antisera. Sera from 23 normal persons and 25 diabetics did not react with any of the antigens. Homogenate antigens detected antibody in 8 of the 11 sera (73%) from suspected or proven cases of zygomycosis, whereas ID tests with filtrate antigens detected antibody in only 2 of the 11 sera (18%). Of the eight sera that reacted with the homogenate antigens, five only reacted with a specific Rhizopus sp. antigen, two only reacted with a specific M. pusillus antigen, and one only reacted with a specific A. corymbifera antigen. Study results show the ID test with homogenate antigens to be more specific and sensitive than the ID test with filtrate antigens and indicate that the former is a promising technique for diagnosing human zygomycosis.
A rapid and simple method for extracting specific cell-free antigens of Coccidioides immitis and Histoplasma capsulatum from agar slant cultures was developed. The extracts were analyzed in immunodiffusion tests for the presence of C. immitis or H. capsulatum specific antigens. These extracts were compared with culture filtrates of brain heart infusion broth subcultures in tests with 32 isolates of C. immitis and H. capsulatum and 13 other fungi which might be morphologically confused with them. The studies showed that the slant extracts were as useful as the culture filtrates and allowed more rapid identification of C. immitis and H. capsulatum. In every case, when an identification was made by conventional morphological methods, the immunological test yielded correlating results. The immunological tests were positive for two isolates that were converted to their yeast forms only after 4 months of study by conventional tests. The new procedure permits the identification of C. immitis and H. capsulatum 2 days after receipt of a pure mycelial-form culture. The test is recommended for the presumptive identification of C. immitis and H. capsulatum cultures.