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Biomedical subjects

L Kaufman

Publications and source records attributed to L Kaufman.

At least 199 records · Page 11Linked to original sources

Immunodiffusion test for serodiagnosing subcutaneous zygomycosis.

Culture filtrate antigens of Basidiobolus ranarum and Conidiobolus coronatus were analyzed by immunodiffusion (ID) with homologous rabbit antisera. B. ranarum and C. coronatus were each found to have five specific antigens. Results of tests with heterologous antisera indicated that all of the species shared at least one antigen. ID tests incorporating the specific precipitin bands as references were developed for detection of basidiobolomycosis and conidiobolomycosis. These tests were performed with sera from humans and horses with proven basidiobolomycosis and conidiobolomycosis as well as with control sera from humans and animals with and without heterologous mycotic and oomycotic infections. Only sera from cases of basidiobolomycosis and conidiobolomycosis produced lines of identity with the reference precipitates of B. ranarum and C. coronatus, respectively. The ID tests were found to be completely sensitive and specific for determining the etiology of zygomycosis caused by these two species. In addition they appeared useful for monitoring resolution of the infections.

Animals↗

MR imaging of the knee with a 0.064-T permanent magnet.

Magnetic resonance (MR) imaging has proved beneficial in the evaluation of internal derangements of the knee. A limitation to general acceptance of MR imaging of the knee has been availability and cost. The recent introduction of low-field-strength MR imaging has shown promise in decreasing the cost and increasing the availability of this modality. High-resolution (pixel size, 0.7 mm2), three-dimensional Fourier transform (3DFT), thin-section (3.5 mm) imaging performed on a 0.064-T permanent magnet was used to evaluate 117 knees in 114 consecutive patients. The appearance of normal anatomy and internal derangements of the knee at low-field-strength imaging is described. Arthroscopic correlation was available for 28 knees. Findings from low-field-strength MR imaging and arthroscopy agreed in 79% of cases in the determination of meniscal tears. Partial-flip-angle techniques with 3DFT produced thin-section images of the knee of diagnostic quality. The authors conclude that in patients with internal derangements of the knee, low-field-strength (0.064-T) MR imaging may provide useful information.

Adolescent↗

Local blood flow measured by fluorescence excitation of nonradioactive microspheres.

An X-ray fluorescence system with low Compton background and high counting efficiency was developed to measure regional blood flow with nonradioactive microspheres. The performance of the system was tested in vitro by counting mixed aqueous solutions of either Mo, Ag, and I; Nb, Ag, and Ba; or Zr, Mo, Rh, Ag, Sn, I, and Ba, as well as a mixture of Ag and Ba nonradioactive microspheres. Mixtures containing 2-20 ppm of each element were counted for 10 min by the fluorescence system, and the individual elements in mixtures of three to seven nonradioactive elements were measured with high accuracy. The best counting statistics were obtained for Ag. For 10-min counts, the system measures as few as 120 Ag microspheres with 30% standard deviation but measures 800 Ag microspheres per sample with 3.6% standard deviation. We compared regional myocardial blood flows determined simultaneously by fluorescence and radioactive microsphere methods; the latter samples were counted by a 3-in. NaI (Tl) well detector and pulse-height analyzer. The radioactive and nonradioactive measurements showed good correlations.

Animals↗

Fibrinopeptide A levels indicative of pulmonary vascular thrombosis in patients with primary pulmonary hypertension.

Although the mechanisms involved in the pathophysiology of primary pulmonary hypertension have not yet been delineated, thrombosis has been implicated. This study was designed to determine whether thrombin activity as reflected by plasma concentrations of fibrinopeptide A (FPA), a marker of the action of thrombin on fibrinogen, is increased in patients with primary pulmonary hypertension. To evaluate fibrinolytic activity, we measured plasma concentrations of tissue-type plasminogen activator, plasminogen activator inhibitor-1, and cross-linked fibrin degradation products. We studied 31 patients with primary pulmonary hypertension. Plasma FPA concentrations measured by radioimmunoassay, were elevated to 87.4 +/- 36.9 ng/ml (mean +/- SEM). Fifteen minutes after administration of heparin (5,000 U), FPA concentrations decreased to 6.8 +/- 1.4 ng/ml (p less than 0.001 compared with preheparin levels). In 21 of 30 patients (70%), FPA concentrations after heparin administration were less than half the preheparin levels, a response consistent with inhibition of thrombin by heparin and the short half-life of FPA. Despite evidence for marked thrombin activity, plasma concentrations of cross-linked fibrin degradation products were normal in all but four patients. Plasminogen activator inhibitor-1 activity was elevated in 19 of the 27 patients in whom it was measured, potentially limiting the fibrinolytic response. The elevations of FPA indicate that thrombin activity is increased in vivo in patients with primary pulmonary hypertension. Thus, sequential assays of plasma markers of thrombosis and fibrinolysis in vivo may help identify those patients who may benefit from treatment with anticoagulants.

Fibrin Fibrinogen Degradation Products↗

Safety, pharmacokinetics and efficacy of once-a-day netilmicin and amikacin versus their conventional schedules in patients suffering from pelvic inflammatory disease.

The safety, pharmacokinetics and efficacy of one daily injection (qd) of amikacin (AK) and netilmicin (NT) was compared with the recommended schedules (cs), i.e. twice-daily or thrice-daily, respectively. Women (17-43 years, n = 78) suffering from pelvic inflammatory disease were randomly assigned to qd or cs of either AK (14 mg/kg per day) or NT (6.6 mg/kg per day). Biometric parameters were similar in the 4 groups and all patients received ampicillin (4 g/day) and tinidazole (0.8 g/day). The Repeated Measures Analysis of Variance was used to distinguish the effects of the schedules and of the drugs choice on critical parameters. Efficacy was similar in the 4 groups and not influenced by the schedule of administration. No significant differences in nephro- and oto-toxicity were observed as assessed by serum creatinine and losses of hearing at low frequencies, but early phospholipiduria and auditory losses at high frequencies were significantly reduced with the qd administration compared to cs and by AK compared to NT. These data suggest that the qd schedule of AK and of NT is as efficacious as their cs schedules, and causes less renal and auditory alterations.

Amikacin↗

Antigenic relationship of Dactylaria gallopava to Scolecobasidium constrictum.

Dactylaria gallopava and Scolecobasidium constrictum were reduced to varietal status under the new combination of Dactylaria constricta (Abbott) Dixon et Salkin var. gallopava (Cooke) Salkin & Dixon, and D. constricta (Abbott) Dixon et Salkin var. constricta, primarily on the basis of the morphologic similarity of their two-celled, dematiaceous, blastic conidia. To appraise this taxonomic change, we studied the antigenic relationship of D. gallopava to S. constrictum using the exoantigen procedure. Exoantigens were prepared from 20 isolates of D. gallopava, seven isolates of S. constrictum and two isolates of S colecobasidium tschawytschae and were tested against reference rabbit anti-D. gallopava and anti-S. constrictum antisera in the presence of their homologous antigens using the micro-immunodiffusion technique. All D. gallopava isolates produced two to three distinct, identical exoantigens. The seven isolates of S. constrictum also produced two to three distinct exoantigens. None of the seven isolates of S. constrictum was reactive against the D. gallopava reference system. Three of the 20 D. gallopava culture filtrate antigens produced one or two precipitin bands of nonidentity with the S. constrictum reference reagents. Both isolates of S. tschawytschae were nonreactive with the D. gallopava and S. constrictum reference reagents. In addition, D. gallopava differed from S. constrictum in the production of a reddish-brown diffusible pigment, growth up to 45 degrees C, and sensitivity to cycloheximide. Based on these physiologic differences and little or no antigenic relatedness between D. gallopava and S. constrictum, we conclude that these two species should be retained as separate entities rather than be considered as varieties of a single species.

Animals↗

[The effect of a histamine nasal provocation tests on the results of the tubal compliance manometry test (TCM) in normal study subjects].

The Tubal-compliance-manometric test (TCM) assesses the passive and active tubal opening as well as the equilibration ability. The pressures necessary to open the eustachian tube (ET) are measured while performing the Valsalva maneuver and during swallowing (if needed with added pressure). The equilibration ability is also checked. Subjects with normal tympanometry were twice tested, at an interval of 1 to 2 weeks; 52 ETs (in 28 persons) entered the study. According to a variance analysis (ANOVA), there was no significant difference (alpha = 5%) between the two measurements (the results were time-independent). The mean opening pressures were 610 daPa (SD = 108) during the Valsalva maneuver and 97 daPa (SD = 40) during the swallow test. Nearly 14% of the tubes were considered floppy (unable to maintain a positive pressure). In order to study the influence of mucosal swelling on tubal function, 9 subjects (18 tubes) underwent a TCM before and after a nasal histamine provocation. The opening pressures in both tests were significantly altered (higher) after the provocation (ANOVA; 0.001 less than p less than 0.01). One tube became obstructed and two became floppy. The equilibration ability was not altered. The TCM proved to be of value as an easy, fast and quantitative test for assessing active and passive tubal function.

Acoustic Impedance Tests↗

CT-scan study of the incidence of sinus involvement and nasal anatomic variations in 196 children.

CT-scan was used to examine rhinosinusitis in the developing sinuses; 196 children aged from 3 to 14 years were selected on the base of their chronic rhinorrhea, nasal congestion and cough. The patients were subdivided into six age groups (3-4, 5-6, 7-8, 9-10, 11-12 and 13-14 years). In the youngest age group, the authors noted maxillary involvement in 63%, ethmoidal involvement in 58%, and even sphenoidal sinus involvement in 29% of the children. Involvement decreased gradually with age, with 10% of ethmoidal and 0% of sphenoidal involvement in the 13-14 years age group. Maxillary sinusitis, however, persisted very frequently in the oldest age group (65%). Frontal involvement seems to become significant at the age of 7-8 years (7%) but it never exceeds 15% (11-12 age group). Septal deviations occurred in 16% of the youngest up to 72% in the oldest age group. The prevalence of bullous conchae increased with age too, although less prominently.

Adolescent↗

Sporothrix schenckii var luriei as the cause of sporotrichosis in Italy.

The second known case of sporotrichosis caused by Sporothrix schenckii var. luriei in a patient living in Piacenza, Italy is described. In the absence of cultures, the diagnosis was based on histologic studies. Stained tissue sections (Hematoxylin and eosin, & Gomori methenamine silver) revealed hyaline, large, thick walled tissue form cells that had divided by septation or a budding process. These forms, along with the striking "eyeglass" configuration of incompletely separated cells that were also present, are the diagnostic features of this apparently rare variety. The use of a fluorescent antibody reagent, specific for S. schenckii, confirmed the identity of the etiologic agent.

Aged↗

The regulation of immunoglobulin production by B cells in patients with endometriosis.

Nineteen patients with endometriosis and 26 control infertile patients were included in the study. All patients were undergoing laparoscopy as part of their infertility evaluations. The study was conducted on sterile heparinized peripheral blood and peritoneal fluid. The age range was 20 to 37 years for both groups. Mononuclear cells were isolated on Ficoll-hypaque density gradients. T cells, B cells, and T cell subsets were identified by the specific immunobead rosette technique. Mononuclear cells 1 x 10(6) were cultured in Roswell Park Memorial Institute medium and stimulated in the presence or absence of pokeweed mitogen. Immunoglobulin production was measured by an enzyme-linked immunosorbent assay. Increased amounts of immunoglobulin (Ig) IgG and IgA were demonstrated in the peritoneal cell cultures (P less than 0.05), whereas peripheral blood cell cultures showed only an increase in IgG in patients with endometriosis (P less than 0.05). There was an increase in the number of T cells, B cells, and the ratio of CD4/CD8 lymphocytes in endometriosis compared with control patients (P less than 0.005) in both peritoneal fluid and peripheral blood. This study suggests that immunoglobulin production by the "activated" B cells may be regulated by the increased presence of T cells, specifically the helper cells (CD4) in endometriosis.

Adult↗

Antigenic relationship of Penicillium marneffei to P. primulinum.

Penicillium marneffei (ATCC 24100) was first isolated from a naturally acquired human infection in the U.S.A. by DiSalvo et al. in 1973. In 1979, this isolate was studied by Pitt who reidentified it as Penicillium primulinum. This prompted us to examine the antigenic relationship between P. marneffei and P. primulinum by comparing their exoantigens. The antigenic relationships of 11 isolates, including the type strains of P. marneffei and P. primulinum, were examined. Each exoantigen extract was tested simultaneously against rabbit anti-P. marneffei and P. primulinum antisera in the presence of the appropriate reference antigens. All eight isolates of P. marneffei, including ATCC 24100, produced two to four specific precipitin lines against their homologous antiserum. However, four of the eight extracts cross-reacted with unabsorbed antiserum to P. primulinum. The P. primulinum extracts contained specific exoantigens which only reacted with the anti-P. primulinum antiserum. Non-specific cross-reactions were eliminated by absorption procedures. On the basis of the specific exoantigens produced by both species, P. marneffei and P. primulinum were found to be antigenically distinct. Isolate ATCC 24100 was shown to be closely related to the other P. marneffei isolates and distinct from P. primulinum. Our results confirm the original identification of ATCC 24100 as P. marneffei and not P. primulinum as Pitt had concluded.

Antigens, Fungal↗

Deoxyribonucleic acid hybridization studies of Exophiala dermatitidis and Exophiala jeanselmei.

Exophiala dermatitidis and Exophiala jeanselmei share similar morphological features and have been confused with each other. To clarify the relationship between the two fungi, we conducted a deoxyribonucleic acid (DNA)-DNA hybridization study using a dot blot method. Between E. dermatitidis and E. jeanselmei, only a very low level of DNA relatedness was seen and it was confirmed that these two fungi are distinct species based on DNA similarity. Close correspondence of DNA from the isolates of E. dermatitidis was obtained, whereas the isolates of E. jeanselmei were divided into 6 groups according to their DNA similarity and a possibility was shown that E. jeanselmei is composed of genetically heterogeneous groups. The subdivision of the species E. jeanselmei by the DNA-DNA hybridization method was in agreement with serotyping exoantigens. This result suggests that DNA-DNA hybridization studies provide an excellent tool for the identification and grouping of pathogenic dematiaceous fungi.

DNA, Fungal↗

Characterization of Cryptococcus neoformans capsular glucuronoxylomannan polysaccharide with monoclonal antibodies.

Mice were immunized with Cryptococcus neoformans serotype A capsular glucuronoxylomannan (GXM) conjugated to bovine serum albumin-adipic dihydrazide. Two splenocyte fusions yielded two monoclonal antibodies (MAbs) that were highly reactive in dot enzyme immunoassay, immunofluorescence, and sandwich enzyme immunoassay. The first MAb, BD-1 [immunoglobulin G1 (kappa) [IgG1(kappa)]], was GXM-A and GXM-D specific, whereas the second MAb, BA-4 (IgM), reacted with GXM-A and GXM-B. A third MAb, CD-6 [IgG1(kappa)], originated from mice immunized with O-deacetylated GXM-C-bovine serum albumin and reacted with GXMs of all four serotypes. Two of the MAbs (CD-6 and BD-1) were further characterized with chemically modified GXMs. Removal of glucuronosyl residues completely inhibited the binding of both MAbs, implicating (1----2)-beta-glucuronic acid as a key component of the epitope. Removal of (1----2)-beta-xylosyl residues decreased reactivity to an intermediate extent. O deacetylation led to a measurable decrease but had the least inhibitory effect of the three GXM derivatives tested. The combining site for these two MAbs appears to be a complex antigenic determinant involving more than one glycosidic residue.

Antibodies, Fungal↗

Indirect enzyme-linked immunosorbent assay for zygomycosis.

A 2-h indirect enzyme-linked immunosorbent assay (ELISA) using homogenate antigens of Rhizopus arrhizus and Rhizomucor pusillus was developed and compared with the existing immunodiffusion (ID) test for zygomycosis, using homogenate antigens of R. arrhizus. Utilizing 1:400 as a minimally positive ELISA titer, 33 of 43 proven cases of zygomycosis were diagnosed. The sensitivity of the ELISA was 81%. The ID test, in contrast, detected only 21 cases and demonstrated a sensitivity of 66%. The specificity of the ELISA was 94%, whereas that of the ID test was 91%. Nonspecific ELISA reactivity was particularly evident with sera from patients with aspergillosis and candidiasis. With the antigens now available, the ELISA was unable to generically or specifically identify the etiologic agents.

Antibodies, Fungal↗

Hepatic neoplasia: breath-hold MR imaging.

Twenty-seven patients with hepatic neoplasms were prospectively examined at 0.35 T with multisection magnetic resonance (MR) imaging during a single breath hold. The procedures included a spin-echo (SE) sequence with a repetition time (TR) of 250 or 125 msec and an echo time (TE) of 15 msec (TR/TE = 250 or 125/15) and gradient-echo (GRE) partial-flip sequences at 250 or 125/20 in phase and 250 or 125/12 out of phase (flip angle of 70 degrees). These procedures were compared with conventional multiacquisition sequences at SE 250/15 (n = 8) in the same patients. GRE partial-flip sequences with a large flip angle provided the optimum combination of contrast and signal-to-noise ratio for imaging hepatic neoplasms, with a signal-difference-to-noise ratio that for in-phase images was 93% greater and for out-of-phase images was 53% greater than that of the SE images. The use of in-phase TEs was preferable to maintain tissue contrast, and presaturation pulses were employed to eliminate vascular pulsation artifacts. All breath-hold procedures provided suppression of motion artifacts superior to that of the short TR, short TE multiacquisition SE imaging. Such sequences should become indispensable for MR imaging of the upper abdomen.

Humans↗