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Biomedical subjects

G E Meyer

Publications and source records attributed to G E Meyer.

At least 19 recordsLinked to original sources
PubMed1997

Histologic differences in benign prostate hyperplasia between Chinese and American men.

BACKGROUND: This investigation sought to determine morphologic differences between Chinese and Americans with symptomatic benign prostatic hyperplasia (BPH), in an admixture of stroma, epithelium, and luminal spaces. METHODS: Adjacent sections of simple prostatectomy specimens from China and the U.S. were stained to highlight the stroma and epithelium. Image analysis was performed on random fields. RESULTS: Chinese tissue had higher glandular densities (mean = 12.5 acini/mm2 vs. 6.2 acini/mm2; P < 0.0001), while American samples had higher percent stroma (mean = 66% vs. 51%; P = 0.0003). Mean luminal cell heights in the Chinese and American prostate acini were 11.7 and 19.0 microns, respectively (P < 0.0001). CONCLUSIONS: These data indicate significant histologic variation in BPH between Chinese and American men undergoing simple prostatectomy. These differences may provide a focus for investigating the epidemiological variation in clinical BPH and carcinoma between our two countries, and could have applications in clinical management of symptomatic BPH.

Aged↗
PubMed1995

Serum basic fibroblast growth factor in men with and without prostate carcinoma.

BACKGROUND: Angiogenesis is essential for the growth of neoplasms. Increased vascularity has been associated with human prostatic carcinoma stage and has been shown to offer prognostic information. Basic fibroblast growth factor (bFGF) is a potent angiogenic inducer expressed in malignant prostate tissue. In this investigation, serum bFGF levels were measured in men with and without prostate cancer. METHODS: Serum bFGF was measured using a commercial enzyme-linked immunosorbent assay in archival serum from men with various clinical stages of prostate carcinoma. Sera from men with negative systematic sector biopsies and serum prostate specific antigen (PSA) less than 2.0 ng/ml served as controls. Prostate volume was measured with transrectal ultrasound. RESULTS: Serum bFGF level was significantly higher in men with prostate carcinoma compared with those without (P < 0.0007). Among 44 men (11 with carcinoma) with a serum PSA less than 4.0 ng/ml, only bFGF level was associated with carcinoma (P = 0.008). Using a cutoff of 1.0 pg/ml, bFGF afforded a sensitivity of 83% and specificity of 44% in this group. There was no association between bFGF levels and clinical stage, Gleason score, or prostate volume. CONCLUSIONS: These data demonstrate that serum levels of bFGF are elevated in most men with prostatic carcinoma. Although association with stage was not observed, the finding of significant elevation in most men with carcinoma who have "normal" serum PSA levels may indicate diagnostic utility for this analyte.

Aged↗
PubMed1994

Texture capture in Necker cubes.

Texture capture can be based on illusory contours, stereopsis, outline figures, real movement, and apparent movement. Several figures are presented that demonstrate texture capture by the use of the pictorial depth cues of the Necker cube. The textures seem affixed to the sides of the cube, follow the alternations of the cube, and extend off the picture plane. A concomitant phenomenon is a subjective rarefaction of the texture in the cube. It is suggested that boundary cues determine the assignation of texture to surfaces.

Form Perception↗
PubMed1991

Use of bar codes in inpatient drug distribution.

The development and operation of a prototype inpatient drug distribution system that uses bar codes is described, and the impact of bar coding on the cassette-filling and verification process is summarized. A prototype pharmacy dispensing site was created to function in parallel with an existing satellite dispensing site that served 78 general medical-care beds. Supplemental labels encoded with an 11-digit unique product identification number, a 5-digit expiration date, and a 6-character lot number were generated and affixed to all unit dose packages dispensed from the prototype pharmacy site. The unit doses were labeled with Code 49 symbology; each label measured 0.8 x 1.25 inches. Each patient cassette was labeled using Code 39 symbology. A cost-benefit model was developed, and the two dispensing systems were compared with respect to (1) time to fill patient cassettes, (2) time to verify patient cassettes, (3) time to process patient charges and credits, (4) time to correct dispensing errors, (5) accuracy of the cassette-filling process, and (6) accuracy of the cassette verification process. Bar-code dispensing and verification saved 1.52 seconds per dose. Additionally, the cassette verification function was shifted from pharmacists to technicians. Estimated per-dose cost of the bar-code system was 2.73 cents. A measurable improvement in the accuracy of filling patient cassettes was documented. The feasibility of using bar codes in unit dose dispensing was demonstrated, and the prototype system was shown to produce cost efficiencies and patient-care benefits.

Clinical Pharmacy Information Systems↗
PubMed1990

Ambiguous fluidity and rigidity and diamonds that ooze!

If white hemicircles rotate over the edges of a black diamond, there occurs an ambiguity of rigidity and motion. As the hemicircles obscure the vertices of the diamond, the figure transforms from a diamond to a rotating, nonrigid cross made of a tar-like fluid. When the corners reappear, the stimulus again becomes a rigid, solid diamond. Visibility of the vertices implies rigidity. If white squares are rotated, fluidity is not perceived. If the diamond has sawtooth edges and the hemicircles are rotated, no fluidity is perceived. Similarly, if illusory contours suggest the amodal completion of the vertices, rigidity is maintained.

Adult↗
PubMed1990

Identification of candidate genes for a factor regulating body weight in primates.

A weight gain of 20-30% above baseline, induced by gastrostomy overfeeding of subhuman primates or gavage overfeeding of rats, was found to completely suppress voluntary food consumption. When overfeeding was discontinued, body weight and oral intake returned in a coordinated fashion to baseline or "set point" values. This regulatory response could have been due to a circulating peptide that was secreted by adipocytes in proportion to the total body energy store and that mediated satiety at the level of the central nervous system. To search for this factor, a subtractive cDNA cloning strategy was developed, permitting the isolation of primate adipocyte genes with augmented expression in the overfed state. A 1.8-kb cDNA clone prepared by subtraction was found to hybridize to a 5-kb message expressed preferentially in the adipose tissue of overfed macaques and rats. This message, which was restricted in distribution among nonadipose tissues, was also detected in human subcutaneous fat. Candidate genes for satiety factors identified by this approach could be used in further studies of body weight regulation and obesity.

Adipose Tissue↗
PubMed1989

Cloning of a putative neuronal nicotinic acetylcholine receptor subunit.

A cDNA clone was isolated from a rat superior cervical ganglion cDNA library with an oligonucleotide that hybridized to muscle-like nicotinic acetylcholine receptor (nAChR) subunit cDNA. The deduced amino acid sequence possesses characteristics expected of a nAChR subunit that does not bind acetylcholine, in addition to distinctive features such as unique cysteine residues and N-linked glycosylation sites.

Amino Acid Sequence↗
PubMed1988

Pharmacy component of a hospital end-product cost-accounting system.

Determination of pharmacy department standard costs for providing drug products to patients at Thomas Jefferson University Hospital in Philadelphia is described. The hospital is implementing a cost-accounting system (CAS) that uses software developed at the New England Medical Center, Boston. The pharmacy identified nine categories of intermediate products on the basis of labor consumption. Standard labor times for each product category are based on measurement or estimation of time for each task in the preparation and distribution of a dose. Variable-labor standard time was determined by adjusting the cumulative time for the tasks to account for nonproductive time and nonroutine activities, and a variable-labor standard cost for each category was calculated. The standard cost per dose included the costs of labor and supplies (variable and fixed) and equipment; this standard cost plus the acquisition cost of a drug line item is the total intermediate product cost. Because the CAS is based on the hospital's patient charges, clinical pharmacy services are excluded. Intermediate products that substantially affect end-product costs (costs per patient case) will be identified for inclusion in CAS reports. The CAS will give a more accurate picture of resource consumption, enabling managers to focus their efforts to improve efficiency and productivity and reduce supply use; it could also improve the accuracy of the budgeting process. The CAS will support hospital administration decisions about marketing end products and department managers' decisions about controlling intermediate-product costs.

Accounting↗
PubMed1987

Effects of flicker-induced depth on chromatic subjective contours.

Two experiments examined the dependence of illusory colors on boundary salience and depth stratification by using flicker-induced depth. The first used a subjective-contour stimulus that appeared as a translucent colored rectangle covering a set of inducing circles and a dark background. The circles were then flickered so as to be perceived as background, and the previously dark background moved forward and appeared as foreground. Simultaneously, the chromatic subjective contour was eliminated. In the second experiment, a subjective-contour (faces/vase-concentric squares) figure was tinted with the McCollough effect, which produced a strong subjective color edge. This edge was visible only with the faces/vase percept and not in the squares percept. Flickering the target locked it into the square configuration because in this case the flicker held the entire pattern in the same depth plane. This eliminated the subjective color edge. Depth stratification and subjective color blockage were maximal at a flicker rate of 6 Hz.

Color Perception↗
PubMed1987

Use of refractive index measurement for quality assurance of pediatric parenteral nutrient solutions.

Use of refractive index measurements to assure accurate formulation of pediatric parenteral nutrient base solutions is described. The refractive indexes for various amino acid and dextrose concentrations were determined. An equation was derived to define the theoretical refractive index for combinations of amino acids and dextrose. Finally, a clinically acceptable range (deviation from theoretical) was determined. The actual refractive index for 300 pediatric parenteral nutrient solutions was compared with the calculated theoretical reading. The actual refractive index for all solutions was consistently predicted by the derived equation. Discussions with clinicians resulted in identification of an allowable range for these readings. All reading were within the identified range. The use of refractive index measurements is a valuable quality assurance tool for pediatric parenteral nutrient base formulations.

Amino Acids↗
PubMed1986

Concurrent antibiotic-use review in a small hospital.

A method of concurrent antibiotic-use review in a 60-bed pediatric hospital is described. The pharmacy department monitors appropriateness of antibiotic prescribing using criteria specified by the pharmacy and therapeutics committee. Antibiotic orders are reviewed by the pharmacist for compliance with the criteria at the time that the orders are written. At three-month intervals, information about the infections treated and the percentage compliance for all physicians, as well as for each individual physician, is compiled and reported to the pharmacy and therapeutics committee. Written and oral feedback are provided to each physician to further improve compliance. This comprehensive monitoring system has resulted in substantial improvement in antibiotic prescribing by physicians at this hospital.

Anti-Bacterial Agents↗
PubMed1984

Visible persistence as a function of spatial frequency, number of cycles and retinal area.

Using a variety of measures it has been shown that processing time increases with increasing spatial frequency. Long and Sakitt (1981) [Vision Res. 21, 1387-1393] investigated duration of visible persistence as a function of both spatial frequency and number of cycles present. They concluded that number of cycles and not spatial frequency is the crucial variable in determining duration of visible persistence. The present paper investigates this issue in three experiments. Experiments 1 and 2 determined duration of visible persistence with spatial frequencies of 2, 4, 8 and 10 c/deg while holding both number of cycles and grating area constant in a dark surround and in a light surround. Stimulus durations of 50 and 300 msec were used in Experiments 1 and 2 respectively. The results at each stimulus duration showed an increase in duration of visible persistence with increasing spatial frequency similar to that found in most previous reports. This increase was less with a 300 than with a 50 msec stimulus duration. Whether the gratings were presented in a light or a dark surround had no significant effect. Experiment 3 showed that at 2 c/deg duration of visible persistence increased with increasing size of the grating stimuli when all stimulus sizes fell within the area of spatial summation. This effect was greater in a dark than in light surround. It is concluded that visible persistence does increase with spatial frequency. Previous results inconsistent with this conclusion are explained in terms of spatial summation.

Afterimage↗