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Biomedical subjects

R B Burns

Publications and source records attributed to R B Burns.

At least 37 records · Page 2Linked to original sources
PubMed1996

The exclusion of non-English-speaking persons from research.

OBJECTIVE: We sought to determine how often non-English-speaking (NES) persons are excluded from medical research. DESIGN. Self-administered survey. PARTICIPANTS: A Medline search identified all original investigations on provider-patient relations published in major U.S. journals from 1989 through 1991, whose methodologies involved direct interaction between researcher and subject (N = 216). Each study's corresponding author was surveyed; 81% responded. MEASUREMENTS AND MAIN RESULTS: Of the 172 respondents, 22% included NES persons; among these includers, 16% had not considered the issue during the study design process, and 32% thought including the NES had affected their study results. Among the 40% who excluded the NES (excluders), the most common reason was not having thought of the issue (51%), followed by translation issues and recruitment of bilingual staff. The remaining 35% (others) indicated that there were no NES persons in their study areas. CONCLUSIONS: NES persons are commonly excluded from provider-patient communication studies appearing in influential journals, potentially limiting the generalizability of study findings. Because they are often excluded through overnight, heightened awareness among researchers and granting institutions, along with the development of valid instruments in varied languages, may increase representation of non-English-speaking subjects in research.

Communication Barriers↗
PubMed1996

Variability in mammography use among older women.

OBJECTIVE: To determine rates of and explore factors associated with mammography use among older women. DESIGN: Retrospective review of part B (physician) bills submitted to Medicare during 1990. SETTING: Health Care Financing Administration (HCFA) data, including sociodemographic information and part B physician bills for all services delivered to Medicare-eligible women in 1990. PATIENTS/PARTICIPANTS: Women age 65 or older as of January 1, 1990, residing in one of 10 states with part B coverage through December 31, 1990. MEASUREMENTS AND MAIN RESULTS: The outcome was receipt of a mammogram (yes/no). We explored factors associated with mammography use within three age groups: 65 to 74, 75 to 84, and 85+. The factors considered were race, state, median income of ZIP Code of residence (from the 1990 US Census, and used to divide the population into quintiles within each state), and number of primary care visits (0, 1, 2, and 3+). Overall, 15% of women had a mammogram: 20% of women age 65 to 74, 12% of women age 75 to 84, and 4% of women age 85 and older. Mammography use was lowest in Oklahoma and highest in Washington. However, in each state the older the age category, the less the mammography use (e.g., 9% vs 5% vs 2% in Oklahoma and 25% vs 16% vs 5% in Washington for women 65-74, 75-84, and 85+, respectively). Mammography use was lower for black than for white women age 65 to 74 (14% vs 21%, P < .001) and 75 to 84 (9% vs 12%, P < .001). Women in each of these two age groups had lower mammography use if they resided in the lowest income quintile and highest if they resided in the highest income quintile (17% vs 23% 65-74, and 10% vs 13% 75-84, P values < .001). Among the oldest women (those 85+), mammography use was low (4%) and varied minimally by race and income (P = .907 and .003, respectively). In all age groups, mammography use was lowest among women who did not have a primary care visit, was greater among women who had at least one visit, and continued to rise with increasing numbers of visits (all P values < .001). For example, among women age 75 to 84, mammography use increased from 5% to 10%, 14%, and 17% for those with 0, 1, 2, and 3+ visits. CONCLUSIONS: We found that mammography use was less for women who were older, of black race, who did not visit a primary care provider, and who lived in areas with lower median income and certain geographic locations (states). Similar factors influenced mammography use in women age 65 to 74, where there is greater consensus as to who should receive a mammogram, and women age 75 to 84, where there is neither consensus nor data. Surprisingly, neither race nor income had much influence on mammography use among women age 85 or older.

Black or African American↗
PubMed1995

Newspaper reporting of the medical literature.

OBJECTIVE: To examine whether the media are providing information to the public about important medical advances in a timely manner and whether the degree of importance is associated with other aspects of newspaper reporting (presence, extent, and prominence). DESIGN: The authors explored the amount, extent, prominence, and timeliness of newspaper coverage received by New England Journal of Medicine and JAMA articles published in 1988, by searching ten leading U.S. newspapers. The journal articles were independently rated based on the public's need to know the medical information contained in the article. The intraclass reliability coefficient for this need-to-know importance score was 0.77. MEASUREMENTS AND MAIN RESULTS: Overall, 35% of the journal articles received newspaper coverage (276/786). The articles were frequently covered by more than one newspaper [extensive coverage (161/276, 58%)] and often appeared on the front page [prominent coverage (42/276, 15%)]. Articles considered most important to the public (92/786, 12%) received more extensive and prominent coverage than did less important articles (p < 0.01). More than three fourths of the newspaper stories appeared within two days of the journal article's issue date. Stories about the most important articles appeared sooner than did those about the less important articles (p < 0.0001). CONCLUSIONS: Articles reported in two prominent medical journals are often viewed as being important to the public, and these articles are receiving newspaper coverage that is extensive, prominent, and timely. This is particularly true for those articles considered most important to the public.

Information Services↗
PubMed1995

Who gets repeat screening mammography: the role of the physician.

To determine rates of, and explore physician factors associated with, repeat mammography, administrative data for 791 women aged 50 years and older were examined. Three-fourths of the women (73%) received repeat mammography (i.e., a second mammogram was obtained within six to 18 months of the first). Provider factors associated with higher repeat mammography rates were: being a woman, practicing in the women's health group rather than the general internal medicine service, and being a fellow or an attending physician (p-values < 0.01). Patients of women attendings/fellows had higher repeat mammography rates than did those of men attendings/fellows, men residents, and women residents. Characteristics (gender, level of training) of providers strongly influence their patients' screening behavior.

Boston↗
PubMed1995

A gas-chromatographic assay method for busulfan with sensitivity for test dose therapeutic monitoring.

A gas-chromatographic assay method was developed and validated for determination of busulfan in human plasma for test dose therapeutic drug monitoring. Busulfan and the internal standard (1,6-bis-(methanesulfonyloxy)hexane) were extracted from plasma samples and derivatized with 2,3,5,6-tetrafluorothiophenol prior to gas chromatographic determination. The 63Ni electron-capture detector provided a limit of quantitation of 0.0100 micrograms ml-1 busulfan in plasma with a linear response over the concentration range 0.0100-0.400 micrograms ml-1. Extraction and derivatization yields were 85.3%-91.0% and greater than 95%, respectively. Assay specificity for busulfan in the presence of potential metabolites was demonstrated. Potentially co-administered drugs gave no response under the sample preparation and chromatographic conditions described for quantification of busulfan. The applicability of this assay to the individualization of busulfan therapy based on a 2 mg test dose is discussed.

Antineoplastic Agents, Alkylating↗
PubMed1993

Gas-chromatographic analysis of busulfan for therapeutic drug monitoring.

The development and validation of a gas chromatographic assay method for determination of total and free busulfan concentrations in human plasma for pharmacokinetic studies is reported. 1,6-Bis(methanesulfonyloxy)hexane, the internal standard, and a potential metabolite, 3-hydroxysulfolane, were synthesized. Plasma and plasma ultrafiltrate samples containing busulfan and internal standard were extracted with ethyl acetate and derivatized with 2,3,5,6-tetrafluorothiophenol prior to gas chromatographic determination. The 63Ni electron-capture detector provided a limit of detection of 0.0600 microgram/ml with a limit of quantitation of 0.100 microgram/ml busulfan in biological samples. Calibration curves were linear from 0.100 to 3.00 micrograms/ml in plasma (500 microliters) and 0.100 to 2.00 micrograms/ml in plasma ultrafiltrate (100 microliters). Extraction and derivatization yields ranged from 78.4% to 89.6% and 56.0% to 71.3%, respectively. Specificity of this assay for busulfan in the presence of its potential metabolites was demonstrated. Also, plasma samples containing co-administered drugs gave no response under these conditions. Clinical samples obtained following administration of a 1 mg/kg oral busulfan dose demonstrate the applicability of this method to analysis of total and free plasma concentrations.

Busulfan↗
PubMed1992

Self-report versus medical record functional status.

The importance of assessing functional status in the hospitalized patient is gaining recognition. However, the availability and accuracy of medical record functional status data are uncertain. We collected data on 2,504 patients greater than 65 years of age discharged alive. A personal interview conducted 2 days before discharge recorded the patient's self-reported ability to perform 5 activities of daily living scales. Medical record abstraction was used independently to determine ability to perform the same activities of daily living scales. Patients who required any human assistance to perform a function were considered dependent. Patients were also contacted after discharge to determine the site of posthospital care (28% discharged to a nursing home). The amount of missing medical record functional status data varied by function from 20% for bathing to 50% for dressing. Ten percent of patients had no medical record functional status documentation concerning any of the five functions. The prevalence of self-reported dependence at discharge varied by function from 24% for feeding to 93% for bathing. The total number of dependencies differed between the two methods (medical records, 2.3 +/- 1.9; self-report data, 3.2 +/- 1.5). There was exact agreement between the two methods on the total number of dependencies in 28% of cases and differences of greater than or equal to 3 in 20%. In a stepwise logistic model predicting discharge to a nursing home and adjusting for other relevant variables, the number of dependencies as determined by self-report and medical record data each remained significant (Odds Ratios = 1.6). Self-report and medical record functional status data differ substantially, and the medical record data remain independently associated with nursing home placement. Several possible explanations for this finding are explored.

Activities of Daily Living↗
PubMed1987

Ochratoxicosis A in young Khaki Campbell ducklings.

Ochratoxin A (OA), a potent nephrotoxic mycotoxin, was fed at 2 ppm in the diet to Khaki Campbell ducklings from hatch to 18 days old. It caused retarded growth, enlargement of the kidneys and liver and regression of the thymus. Light and electron microscopical changes seen in the liver included an accumulation of glycogen and the presence of mis-shapen mitochondria in the hepatocytes. OA caused thickening of the glomerular basement membrane and in infiltration of lymphoid cells into the kidney. There was an increased deposition of IgG in the glomeruli. OA-fed ducklings had normal levels of circulating IgG in their sera and there was a subepithelial migration of IgG-positive cells in the bursa of Fabricius. In general, OA-induced changes seen in ducklings, both with the light and electron microscopes, were similar to, but less pronounced than those seen in the fowl and turkey.

Animals↗
PubMed1987

Skeletal changes in broiler chicks and turkey poults fed diets containing ochratoxin A.

Broiler chicks and turkey poults were divided at hatching into experimental and control groups. Experimental birds were fed a diet contaminated with 4 ppm ochratoxin A, whereas the ration of control birds was confirmed to be mycotoxin free. Birds were killed at fortnightly intervals up to 10 weeks old and skeletal changes were investigated. Almost all experimental birds developed generalised skeletal osteopenia with disturbed endochondral and intramembranous bone formation. Histological changes in diaphyseal cortices could account for the reduced breaking strength of bones from birds fed mycotoxin, which have been reported by others. One bird showed changes consistent with a diagnosis of hypophosphataemic rickets. In others, however, osteoid formation was defective and changes were interpreted as osteoporosis. Although it might be tempting to suggest that osteoporosis is a result of a direct toxic effect of ochratoxin on osteoblasts, the effect of inanition, inactivity and general debility may be equally important.

Animals↗
PubMed1987

Ultrastructural study of ochratoxicosis in quail (Coturnix coturnix japonica).

Ultrathin sections of liver and kidney from 11-week-old quail fed, from day-old, ochratoxin A (OA) (mixed in the diet at levels of 4 and 8 ppm) were examined in the electron microscope. Pathological changes in the kidneys were limited to the proximal convoluted tubules (PCT) and glomeruli. In the PCTs, abnormal mitochondria and excessive numbers of lipid droplets were the principal findings with glomeruli showing thickened basement membranes. Swollen mitochondria and variable glycogen deposition were the chief features present in the livers. It is suggested that OA is more hepatotoxic in quail than in broilers, as well as being nephrotoxic.

Animals↗
PubMed1986

Ultrastructure of Peyer's patches in the domestic fowl and turkey.

Peyer's patches in the fowl and turkey were indistinguishable at the ultrastructural level and were similar in many respects to those found in mammals. They were overlaid by a lymphoepithelium containing undifferentiated intestinal epithelial cells with a well developed microvillous border, follicle associated epithelial (FAE) or M cells with short blunt microvilli, lymphocytes and plasma cells. FAE cells had a lightly stained cytoplasm with vacuoles and vesicles. They were similar to mammalian FAE cells. The lymphoid aggregates of Peyer's patches consisted of small and large lymphocytes, lymphoblasts and plasma cells. Macrophages and globule leucocytes were seen among the lymphoid cells.

Animals↗
PubMed1986

A fine structural study of the turkey harderian gland.

The ultrastructure of the turkey Harderian gland is described and the findings support previous histological descriptions of the gland. The gland is a compound tubulo-acinar structure composed of characteristic bipolar epithelial cells providing a predominantly merocrine secretion to the lumina. In the basal aspect of the cell, aggregations of non-secretory lipid-like droplets were evident and apically, the secretion was mucoid. The cells had abundant mitochondria, granular endoplasmic reticulum, ribosomes and a complex network of Golgi elements. In the subepithelial regions, myoepithelial cells and large numbers of plasma cells were seen. Within the granular endoplasmic reticulum cisternae of the epithelial cells, fibrillary or crystalline rods in some instances measuring up to 10 micron in length, with a 7.0 nm repeat pattern, were frequently seen.

Animals↗
PubMed1986

Experimental stimulation of eosinophil production in the domestic fowl (Gallus gallus domesticus).

A method has been devised to produce eosinophilia in birds experimentally. Multiple intraperitoneal injections of bovine serum albumin (BSA) produced a greater response than horse serum in young adult fowls, and injections of 2 ml BSA were more effective than injections of 0.2 ml. The highest eosinophilic responses were obtained with injections of BSA together with aluminium hydroxide. Thymectomy had little effect on eosinophil numbers following horse serum injections but irradiation produced a depressed response. Horse serum that had been heated to 56 degrees C for 30 minutes to inactivate complement and to denature proteins, including possible horse IgE, induced an eosinophilic response in 50 per cent of birds compared with only 14 per cent with unheated horse serum. Furthermore, when the former birds were reinjected after a rest period of 13 weeks, the eosinophilic response followed a similar curve as before but a higher proportion of birds responded. Birds aged over two years did not give a good eosinophilic response after horse serum stimulation. There was no consistent correlation between raised IgE levels and eosinophil numbers. Tolerance to horse serum was detected in some birds using a radial immunodiffusion technique. Analyses of blood plasma from birds with eosinophilia showed a significant increase in total amino acids compared with normal birds.

Agar↗
PubMed1985

A multicenter study with ketotifen (Zaditen).

Seven hundred and thirty-three atopic asthmatic patients were entered into two multicenter double-blind double-placebo controlled studies comparing the prophylactic effects of ketotifen (445 patients), placebo (143 patients), disodium cromoglycate (72 patients) and theophylline (73 patients). The primary measure of therapeutic effects was a decrease in concomitant medication without a significant increase in symptomatology or a decrement in pulmonary function: in both studies ketotifen was shown to be an effective and safe therapeutic agent at an oral dose of 1 mg bid. The positive control, DSCG, was also shown to be effective when used properly, while theophylline did not show a significant prophylactic effect.

Administration, Oral↗
PubMed1985

Cytodestructive mechanisms provoked by food antigens: III. Inhibition of direct and antibody-dependent allergic autocytotoxicity (ACT) by ketotifen.

In vitro challenge of peripheral white blood cells (WBC) from 15 food sensitive individuals and 16 asymptomatic controls was studied in allergic autocytotoxicity (ACT) assay using extracts of cow's milk, corn, and wheat. The observed disintegration of the WBC in the direct and antibody-dependent ACT was inhibited by ketotifen in a linear, dose-dependent manner. Therefore, our data demonstrate that the ACT response is associated with anaphylactic injury which is prevented by pretreatment with ketotifen, in vitro.

Adult↗