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Biomedical subjects

M L Taylor

Publications and source records attributed to M L Taylor.

At least 91 records · Page 5Linked to original sources

Evaluation of phagolysosome fusion in acridine orange stained macrophages infected with Histoplasma capsulatum.

A phagosome-lysosome (PL) fusion was performed in vitro using peritoneal cells from normal BALB/c mice and the J774.2 macrophage cell line infected with the yeast phase of the fungus Histoplasma capsulatum at ratios of 5 x 10(5), 5 x 10(6) or 1 x 10(7) yeasts per 1 x 10(6) macrophages, and phagocytosis was allowed to proceed for 5, 30 and 60 min. Macrophage lysosomes were pre-labelled with acridine orange and the cells were challenged with the parasite. Fusion was evaluated by fluorescence microscopy and the number of macrophages with stained yeast cells was scored. The phagolysosome fusion frequency (PLFF) was calculated by subtracting the specific fusions of infected macrophages from the non-specific fusions of uninfected macrophages and normalizing the total number of bound yeasts. The PLFF was determined using different doses and strains of H. capsulatum. Results showed that PLFF in infected macrophages depends on the infection dose. Inhibition of PL fusion was detected mainly at a high infection ratio (1 x 10(7) yeasts/1 x 10(6) macrophages), and PL fusion varied with phagocytosis time. No significant differences were observed in the fusions when different Histoplasma strains were used. Results with J774.2 cells were similar to peritoneal cells, indicating that both methodology and fusion calculations employed were useful, in spite of the heterogeneity of macrophage populations used.

Acridine Orange↗

Immunosuppression transfer by spleen cells from young to adult mice previous to Histoplasma capsulatum infection.

The passive transfer of spleen cells from 1 month old mice into adult syngeneic mice, abrogates their resistance to histoplasmal infection. This suppressive state was detected in two cell populations, one non-adherent and another adherent with radioresistant characteristics. The transferred spleen cells were treated by different anti-sera: anti-theta, anti-adherent cells (produced in rabbits) and monoclonal anti-Thy 1.2 respectively. The irradiated and non-irradiated adult recipient mice were infected with Histoplasma yeasts utilizing the Lethal Dose50 for 1 month old mice. The infection course was determined by death percentage, the histoplasmosis murine signs and the number of the fungal colony forming units (CFU) from the infected spleens. The results of the anti-sera treatment suggest that non-adherent as well as adherent cells participate in the suppressive phenomena. A lower number of CFU was identified in infected animals which received cells treated with anti-Thy 1.2 anti-sera.

Agglutination Tests↗

Acute effects of a zinc supplement taken before a glucose load.

Observations from animal studies suggest that individuals who consume oral zinc supplements may show elevations in blood glucose. To examine whether this effect occurs in humans, we conducted glucose and zinc tolerance tests on eight adult women volunteers. All eight volunteers were subjected to two test conditions: (a) ingestion of 50 g D-glucose and (b) ingestion of 110 mg ZnSO4.7H2O followed 60 minutes later by ingestion of 50 g D-glucose. Two subjects also ingested 110 mg ZnSO4.7H20 without glucose. Blood samples were drawn before and 15, 30, 45, 60, 90 and 120 minutes following consumption of the glucose solutions, and were analyzed for glucose and zinc content. Our results did not indicate significantly altered glucose tolerance in response to the acute elevation of plasma zinc. These preliminary data suggest that increasing plasma zinc prior to elevating blood glucose does not alter the rate of glucose removal from circulation or the area under the glucose curve in normal individuals.

Adult↗

Partial characterization of a rapidly released antigenic/allergenic component (Ag 5) of Aspergillus fumigatus.

An antigenic component of Aspergillus fumigatus, which was responsible for inducing an initial early antibody response in rabbits immunized with A. fumigatus germlings, has been identified and partially characterized. By immunofluorescent antibody and ELISA techniques, this antigen was demonstrated to be present on the germling surface, although it was also detected in supernatants of conidia/germlings within 1 hour and was present in all shake and stationary culture-filtrate extracts. By incorporation of a monospecific antiserum to this component in an intermediate gel of the reference self-crossed radioimmunoelectrophoresis pattern for allergic bronchopulmonary aspergillosis sera, it was recognized as Ag 5 and was also demonstrated to bind specific IgE. Further immunochemical analyses have revealed that Ag 5 is relatively heat labile, does not bind to concanavalin A, and has a molecular weight of approximately 35 kd. This rapidly released antigenic/allergenic component may play an important role in the initiation of immunologic responses in patients with allergic bronchopulmonary aspergillosis.

Antigens, Fungal↗

Urine glycosaminoglycans in a reference population: effects of age, body surface area, and postmenopausal status.

Urine glycosaminoglycans and hydroxyproline have been measured in an adult reference population containing significant numbers of those over 65 years. Urine concentrations of glycosaminoglycans remain constant into old age providing body weight is maintained and correlate significantly with body surface area. The urine ratio of glycosaminoglycans to creatinine rises markedly in women after menopause resulting in a bimodal frequency distribution. This ratio is worth further investigation as a marker of postmenopausal osteoporosis.

Adult↗

Anticonvulsant medication use and circulating levels of total thyroxine, retinol binding protein, and vitamin A in children with delayed cognitive development.

Circulating thyroxine (T4), retinol binding protein (RBP), and vitamin A were measured in conjunction with nutritional status assessment of 707 cognitively delayed children, ages 3.0-9.0 y. Twenty percent were receiving anticonvulsant (AC) medication. T4 was lower and RBP and vitamin A were higher (p less than 0.0001) among AC than non-AC subjects. Molar ratios of vitamin A:RBP did not differ between the two groups nor did intakes of protein or vitamin A. Lower T4 and higher RBP were found among children who received diphenylhydantoin (DPH), phenobarbital, or AC combinations, but vitamin A was higher only among those who received DPH. RBP and vitamin A were lower (p less than 0.05) among children with infections and vitamin A was lower (p less than 0.05) among those with serum zinc less than 70 micrograms/dL (less than 10.7 mumol/L); differences between AC and non-AC subjects remained when other variables were considered.

Anticonvulsants↗

Zinc status in women with recurrent vulvovaginal candidiasis.

Zinc status has been shown to influence various cell-mediated immunologic mechanisms. These cell-mediated mechanisms are important in preventing mucocutaneous infections caused by Candida albicans. This study evaluated the relationship between zinc status and recurrent vaginal candidiasis by comparing plasma and erythrocyte zinc in 29 patients with recurrent vaginal candidiasis and 20 control subjects matched for age, race, and parity. The results indicated that there was a significantly lower level of plasma zinc in women with recurrent vaginal candidiasis (81 + 11.6 mg/dl) than in the control subjects (91 +/- 14.2 mg/dl) with a significant value of p = 0.015. These differences in plasma zinc levels were even greater when adjusted for dietary zinc and supplemental zinc with the use of analyses of covariance. No differences in erythrocyte zinc measurements were found between the two groups. These results suggest that mild zinc deficiency is associated with recurrent vaginal candidiasis and may play a role in the susceptibility of women to recurrent vaginal candidiasis.

Candidiasis, Vulvovaginal↗

Range ambiguity in pulsed Doppler ultrasound: the ambiguity clarified?

Pulsed Doppler ultrasound (PW) can be used to determine the location of frequency shifts within the cardiac chambers or great vessels. However, it is possible to record similar frequency shifts at sample volume locations distal to their original site; this is referred to as range ambiguity (RA). Eleven patients were studied with combined Doppler and two-dimensional echocardiography (2-D) to determine the circumstances in which RA occurs. Mapping of various flow patterns with PW was performed in each of four 2-D views beginning at 2 cm distances from the transducer and at subsequent 1-cm intervals until the maximal range of the PW was achieved. Range ambiguity was demonstrated only in the four-chamber view in patients with enlarged cardiac chambers or if an abnormal flow pattern was present. The site of origin of the ambiguous signals was dependent on the pulse repetition frequency (PRF) employed. Range ambiguity occurs more often when a relatively high PRF is used. Range ambiguity may be used for mapping of abnormal flow beyond the range of PW or for recording of high velocities at sample volumes far from the transducer without frequency aliasing.

Aged↗

Sources and fate of polychlorinated dibenzodioxins, dibenzofurans and related compounds in human environments.

Several of the major incidents resulting in potential human exposures to polychlorinated dibenzodioxins (PCDDs) and/or polychlorinated dibenzofurans (PCDFs), polychlorinated biphenyls (PCBs) and related compounds which have occurred in the U.S. in recent periods have resulted from improper disposal of hazardous chemical wastes. Prominent examples of such environmental contamination episodes are the Love Canal, into which ton quantities of chlorinated organic compounds containing substantial concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) were deposited; numerous sites in the State of Missouri which were contaminated by the dumping of chlorinated organic wastes containing various PCDDs and possibly PCDFs, and PCBs; and the environs of a 2,4-D/2,4,5-T manufacturing plant site in Arkansas, which were contaminated with PCDDs. Environmental assessments of such sites have revealed extensive contamination of soils, waterways, fish and other biological species with these toxic compounds, which in turn could lead to human exposures. Other recently identified sources of PCDDs, PCDFs and related compounds in human environments include stack effluents from municipal refuse incineration, and fires and explosions involving electrical devices containing PCBs and polychlorinated benzenes. Data obtained in assessments of such incidents are presented, and the implications of these findings with respect to the distribution and persistence of PCDDs, PCDFs and related chemicals in the environment and possible effects on humans are discussed.

Accidents↗

Relationship between age and cellular suppressive activity in resistance to Histoplasma capsulatum infection.

One-month-old and 1-year-old male BALB/c mice showed a lower resistance than 4.5-month-old mice to Histoplasma capsulatum infection. 4.5-month-old mice successfully resolved the infection when challenged with either a LD50 or LD100 for 1-month-old mice. A critical clinical course of experimental histoplasmosis was observed in 4.5-month-old syngeneic mice when spleen cells from 1-month-old BALB/c mice were transferred to them. Irradiated recipient mice, into which bone marrow and spleen cells were transferred, died when infected with the LD100 for 1-month-old mice. The same occurred with 4.5-month-old non-irradiated infected mice which received only spleen cells and with 1-month-old mice which were used as a control of infection. However, infected and non-transferred 4.5-month-old mice survived this dose. Thus, the adoptive transference of spleen cells from 1-month-old mice to 4.5-month-old mice suppressed the resistance of these adult mice to infection. Apparently, the transference of the suppressive state requires the presence of two cell populations, a non-adherent and an adherent and radioresistant cell present in the spleen of male 1-month-old mice.

Age Factors↗

Energy and nutrient values from different computerized data bases.

Twenty-four dietary records were analyzed using three computerized nutrient data bases. Differences in mean values were found for 9 of 19 variables evaluated. No one data base consistently yielded highest or lowest values for all nutrients. Mean values appeared to be most consistent among the data bases for energy and the energy-yielding nutrients, calcium, phosphorus, and magnesium. Even when mean values did not differ significantly, values for some individual diets were widely discrepant. Whether comparisons of calculated energy and nutrient values are within or between studies and based on a few or many days of dietary information, values should be recognized as estimates and their limitations and strengths respected.

Child↗

Antigens from Histoplasma capsulatum and Blastomyces dermatitidis. I. Immunological comparative studies from polysaccharide-protein complexes of both fungi.

Certain groups of fungi share chemical structures which makes difficult isolation and differentiation of specific antigens by the usual methods of extraction and purification. Therefore, we have oriented our studies to the immunological and biochemical characterization of differences and similarities of molecular structures from fungi, etiologic agents of systemic mycoses, hoping to establish criteria for the utilization and handling of these antigens. A deproteinized polysaccharide-protein complex (D-PPC) was isolated from Histoplasma capsulatum and Blastomyces dermatitidis. The immunological studies with humoral tests indicate a variable cross reaction between antigens of both species. In immunodiffussion systems, the reaction was specific for each species using saline solution of phosphate butter solution, while using an agarose veronal system, the cross reactions were very evident. In addition, differences in cross reactions were obtained with immunoelectrophoresis, haemagglutination and complement fixation microtest. This variation to cross reaction responses suggest that these antigens (D-PPC) share common structures but at the same time must have some different component owned by each one of the fungi which makes them more specific than crude antigens.

Antigens, Fungal↗

Immunology of histoplasmosis: humoral and cellular activity from a polysaccharide-protein complex and its deproteinized fraction in experimentally immunized mice.

In a previous publication it was reported that a polysaccharide-protein complex (PPC), sensitive to beta-glucosidase, was isolated from Histoplasma capsulatum. This complex was strongly reactive in an agar gel diffusion assay with sera from patients with histoplasmosis, but was unreactive with sera from patients with coccidioidomycosis. Here, the studies with human sera have been expanded and attempts were made to determine the response of mice immunized with nonviable H. capsulatum or Coccidioides immitis to PPC or its deproteinized fraction (D-PPC) using more sensitive tests for antibody and including also test for cell-mediated immunity. Histoplasmin and coccidioidin were compared with PPC or its deproteinized fraction (D-PPC) in all assays. In a counterimmunoelectrophoresis (CIE) assay, PPC and D-PPC reacted only with sera from patients with histoplasmosis, whereas cross reactions were noted with histoplasmin and coccidioidin using heterologous sera. Cross-reaction were observed with all four antigen preparatins and both types of antisera using a microcomplement fixation assay. The assay for macrophage migration inhibitory factor (MIF) was also relatively nonspecific, in that inhibition occurred with cells from animals sensitized with Histoplasma or Coccidioides using both homologous and heterologous antigens. In the footpad assay, histoplasmin and coccidioidin were highly cross-reactive in animals sensitized with the heterologous fungus, but the PPC and D-PPC from H. capsulatum elicited significant reactions only in animals sensitized with Histoplasma.

Animals↗

Crown construction to the lingual margin of a partial denture.

A technique is described which ensures that the interface between a newly constructed crown and an existing partial denture is accurate and neither crown nor denture need adjustment. At no time does the patient have to be without the denture. A silver plated die with a double dowelling technique is used.

Calcium Sulfate↗