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Biomedical subjects

D Abramson

Publications and source records attributed to D Abramson.

100 records · Page 6Linked to original sources
PubMedDate not supplied

Mycotoxin production in amber durum wheat stored at 15 and 19% moisture content.

Ochratoxin A and citrinin developed in 11 kg parcels of amber durum wheat at 15% and 19% initial moisture content (MC) exposed to simulated bulk storage in a Manitoba granary for 60 weeks between July 1984 and September 1985. Other biotic and abiotic variables were monitored throughout the storage period. Ochratoxin A reached maximum levels of 11.8 and 0.11 ppm at 19 and 15% initial MC, respectively, during weeks 44-48; citrinin reached levels of 80.0 and 0.65 ppm at these respective moistures during the same period. The effect of 19% initial MC was significantly greater for the following variables: ochratoxin A, citrinin, Aspergillus flavus, Aspergillus glaucus group species, Alternaria species, Aspergillus versicolor, bacteria, fungal propagule count, seed germination, O2, CO2, moisture content, and fat acidity. Principal component analysis indicated that the first two components, describing greater than 60% of the variability in the data, partially defined the ecological relationships leading to mycotoxin production in the stored durum wheat system.

Alternaria↗
PubMedDate not supplied

The incidence and distribution of ochratoxin A in western Canadian swine.

A survey of swine destined for slaughter in Manitoba was conducted to examine the incidence of ochratoxin A (OA) in swine herds from different regions of Manitoba throughout the year 1989-90. Thirty-six percent of the serum samples which were collected from 1600 pigs contained detectable levels of OA. The identity of this toxin was confirmed using liquid chromatography-mass spectrometry and enzymatic hydrolysis. There was a significant effect of the region from which the herds originated, as well as the season in which the samples were collected on both the incidence (p < 0.001) and concentration of OA (p < 0.001). In July, 65% of the samples contained detectable levels of OA, compared with 38, 21 and 17%, in April, October and January respectively. Furthermore, 24% of the samples collected in July contained greater than 15 ng/ml of OA, while only 2, 9, and 1% of the samples collected in April, October and January respectively, contained greater than 15 ng/ml of OA. Based on the six samples collected from each herd, it appears that the presence and concentration of OA within a herd may be estimated from a limited number of animals per herd.

Animals↗
PubMedDate not supplied

Results of external beam radiation for children with retinoblastoma: a comparison of two techniques.

From 1979 through 1987, 82 children with retinoblastoma were treated with primary external beam therapy, to one or both eyes. A total of 120 eyes were irradiated, with doses from 3850-5000 cGy. We used a lens-sparing electron beam technique from 1979 to 1984 and a modified lateral beam technique from 1984 to 1987. Comparison of outcome for eyes with Group I-III (Reese-Ellsworth) disease revealed a significant advantage for freedom from relapse favoring the lateral technique (p = 0.0009). A similar trend was noted for final eye outcome (need for enucleation). No differences were noted for eyes with Group IV-V disease. Patient survival was 90% at 4 years, with a mean follow-up time of 36 months.

Child, Preschool↗
PubMedDate not supplied

Vendor agreements offer cost savings for cardiac catheterization.

Hospitals continue to search for ways to save money at the same time they provide their physicians and clinical staffs with the variety and quality of supplies needed to do their jobs. St. Joseph's Medical Center in Stockton, Calif. watched expenditures for its cath lab increase while its activity stabilized. They looked at their high-volume use of balloon catheters, says Gary Boyd, service director. At a cost of $600 to $700 apiece, it made sense to carefully manage their supply. Choosing a prime vendor was the first step in controlling inventory. Materials management, which had previously had a hands-off policy in the cath lab, took an active role in determining choices for this product. Through a lengthy selection process, medical center management and physicians reached a consensus for a single vendor. Having a prime vendor policy may increase the vendor's commitment to the hospital and provide added advantages. For St. Joseph's, selecting a prime vendor has better positioned the hospital to arrange for inventory to be stocked on consignment: the vendor owns the shelved supplies, which the hospital pays for only as they are used. However, some vendors may reduce their discounts when they enter into a consignment agreement. The best way is to get the maximum discount on the invoice price first, and then work with the vendor to manage inventories at the lowest level possible. Smaller facilities have less leverage and less flexibility, but they can often piggy-back onto large bargaining agreements by partnering with a larger institution.

California↗
PubMedDate not supplied

Rapid determination of citrinin in corn by fluorescence liquid chromatography and enzyme immunoassay.

A rapid assay procedure was developed for mycotoxin citrinin in corn using liquid-liquid extraction (LLE) cartridges. Ground corn was extracted with methylene chloride and 0.5 N phosphoric acid. The extract was added to an LLE cartridge containing a diatomaceous-earth adsorbant, previously impregnated with sodium bicarbonate solution. After aspiration to dryness, the cartridge was eluted with methanol-water (4 + 1), and aliquots were taken for quantitation by reversed-phase liquid chromatography with fluorescence detection. Recoveries of citrinin added to ground corn at 200-1600 ng/g ranged from 71.2 to 86.3%, with coefficients of variation between 4.1 and 10.6%. An indirect enzyme immunoassay was also evaluated, using sodium carbonate solution for extraction. Recoveries of citrinin added to ground corn at 200-2000 ng/g ranged from 53.2 to 67.2%, but the coefficients of variation varied between 18.4 and 51.5%. The LLE cartridge procedure offers the advantages of low solvent consumption and speed, and is amenable to automation.

Adsorption↗
PubMedDate not supplied

Determination of sterigmatocystin in barley by acetylation and liquid chromatography.

The estimation of sterigmatocystin by fluorescence liquid chromatographic analysis of the acetate derivative has eliminated the background interference normally encountered in analysis of underivatized sterigmatocystin in barley. Barley samples are extracted with acetonitrile-water; the extract is then washed with hexane, transferred to chloroform, and eluted from a silica gel column with cyclohexane-ethyl acetate. The extract is heated with pyridine and acetic anhydride for 3 h to give a stable derivative. Reverse-phase liquid chromatography, using a methanol-water mobile phase gradient and fluorescence detection, is the method of determination. Recoveries from barley samples spiked with 20, 110, 190, and 765 micrograms sterigmatocystin/kg were 31, 69, 75, and 96%, with coefficients of variation between 2.8 and 5.4%. Sterigmatocystin is confirmed by comparing retention times in underivatized extracts of samples and standards, using methanol-water (3 + 2) mobile phase and ultraviolet detection.

Acetylation↗
PubMedDate not supplied

Metastatic retinoblastoma and L-phenylalanine mustard-dianhydrogalactitol.

Retinoblastomas heterotransplanted to nude mice were shown to be sensitive to a combination of phenylalanine mustard and dianhydrogalactitol. A patient with metastatic retinoblastoma was treated with this combination and had a significant response with complete clinical clearance of her bone marrow and metastatic tumors. However, the patient's response was similar to that observed in nude mice; recurrences of tumors developed after complete clinical remission.

Animals↗
PubMedDate not supplied

A balancing act: the tension between case-finding and primary prevention strategies in New York State's voluntary HIV counseling and testing program in women's health care settings.

This study sought (1) to identify factors that influence women's willingness to accept voluntary HIV counseling and testing at New York State Family Planning Programs (FPPs) and Prenatal Care Assistance Programs (PCAPs) and (2) to evaluate the effectiveness of such a voluntary counseling and testing program. Telephone interviews elicited organizational-level data from 136 agencies; a combination of telephone and face-to-face interviews was used to gather provider data from 98 HIV counselors; and client data were gathered from 354 women in face-to-face interviews at counseling sites. Slightly fewer than 60% of women agreed to be counseled, and, of those, under half consented to an HIV test at the counseling site. Approximately two thirds of the women who were tested returned for their results and posttest counseling. Clients' recall of pretest counseling content was relatively poor. Bivariate and regression analyses suggest that client, provider, and organizational factors are all associated with rates of pretest counseling and testing. The current voluntary counseling and testing program is achieving only moderate success. Although a substantial number of clients accept HIV counseling, many women remain reluctant to consent to HIV testing, and many who accept testing do not return for their results. Moreover, among those who receive pretest counseling, many do not recall important informational content, which suggests variation may exist in the quality of counseling or that one-time HIV counseling interventions are insufficient to communicate complex information. Medical Subject Headings (MeSH): AIDS, HIV serodiagnosis, women's health, patient education.

AIDS Serodiagnosis↗
PubMedDate not supplied

Determination of citrinin in barley by indirect and direct enzyme immunoassay.

Polyclonal antibodies against the mycotoxin citrinin were raised in rabbits after immunization with citrinin conjugated to keyhole limpet hemocyanin. The antibodies were used in a competitive indirect enzyme immunoassay (EIA) with citrinin coupled to glucose oxidase as the solid-phase antigen for coating microtiter plates. Detection limits of this indirect EIA for citrinin ranged from 0.4 to 0.8 ng/mL for buffer solutions. Recoveries of citrinin added to ground barley at 100-2000 ng/g ranged from 105 to 112%, with coefficients of variation between 4.5 and 12%. A direct competitive EIA also was established, with citrinin coupled to horseradish peroxidase as the labeled antigen. Detection limits of this direct EIA for citrinin ranged from 2 to 4 ng/mL for buffer solutions. Recoveries of citrinin added to ground barley at 500-2000 ng/g ranged from 108 to 111%, with coefficients of variation between 8.4 and 26.9%. In naturally contaminated barley samples assayed with the indirect EIA, optimum extraction of citrinin was obtained in 30 min, and only one extraction was necessary to recover 72-76% of the analyte.

Adjuvants, Immunologic↗