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Biomedical subjects

R E Pearson

Publications and source records attributed to R E Pearson.

At least 91 records · Page 5Linked to original sources

Herpes simplex virus cloned DNA fragments induce coumermycin A1 resistance in Escherichia coli.

We have taken a new approach to identify and fine map previously undescribed herpes simplex virus (HSV) functions. In experiments described in this report the antibiotic coumermycin A1 was used to select two HSV type 1 BamHI fragments cloned in pBR322 that confer partial resistance to drug-susceptible Escherichia coli. The genes encoding these HSV functions have been designated cour-1 and cour-2 and have been fine mapped to the HSV sequences. HSV-cour1 is located at the left end of BamHI-F near HSV type 1 genomic map coordinate 0.645. cour-2 maps to BamHI-M', which is a 159-base-pair internal component of the alpha ICP4-coding sequence located in the reiterated sequences of the S component. In pBR322 both inserts apparently rely on the tet promoter for expression. Additionally, cour-2 functions when present as a BamHI insert in pUC7. The analysis of cour-2 "maxi" cell proteins reveals the presence of proteins produced by the fusion of HSV-1 BamHI-M' sequences and the sequences of the vector genes, i.e., the major tet product for pBR322 and the modified beta-galactosidase for pUC7. These data suggest that the development of bacterial assays for fusion products of eucaryotic DNA open reading frames in plasmid vectors may be a useful technique for initiating gene function studies.

Aminocoumarins↗

Effect of ratio of corn silage to grass-legume silage with high concentrate during dry period on milk production and health of dairy cows.

Four corn silage: gross legume silage: concentrate totally mixed diets 1) 75:25:0; 2) 48.75:16.25:35; 3) 50:50:0; and 4) 32.5:32.5:5.35 were fed to Holsteins in second and third lactation for two complete lactations. Cows fed diets 1 or 2 during dry period were fed diet 2 during lactation. Diets did not affect length of dry period or lactation, calf weight, milk protein percent, or milk fat percent. Feeding concentrate during dry period increased gain from .63 to 1.11 kg/day. Feeding higher grass-legume silage diets 3 and 4 increased gain during lactation from .25 to .35 kg/day. On a mature equivalent basis, cows fed high corn silage diets 1 and 2 produced more milk (7,105 versus 6,663 kg), protein (236 versus 216 kg), fat (267 versus 245 kg), solids-not-fat (612 versus 564 kg), and a higher solids-not-fat percent (8.62 versus 8.50%) than diets 3 and 4. Diets did not alter health or reproduction. Production and weight gains favored feeding diet 1 during dry period and diet 2 during lactation.

Animal Feed↗

Relationships between linear type scores, objective type measures, and indicators of mastitis.

Objectives were to examine the usefulness of objective measures of conformation and linear scores for type for predicting indicators of mastitis. Approximately 300 cows in five herds were scored in the experimental linear classification program of the Holstein-Friesian Association of America, measured objectively for numerous components of conformation, and evaluated for four indicators of mastitis. Indicators of mastitis were average natural logarithm of somatic cell counts during the lactation, percent of samples (taken approximately every 3 mo) infected during a lactation, percent of samples infected with Staphylococcus aureus, Streptococcus agalactiae, Escherichia coli, Klebsiella, and percent of samples with signs of mastitic milk. Relationships between conformation and mastitis often were inconsistent because of moderate or low correlations between indicators of mastitis. Indicators of mastitis were predicted from results of multiple regression analyses with subjective scores and objective measures of type as independent variables. Largest differences of predicted indicators of mastitis from variation in any single type trait were sufficient to be important economically, but average differences were much smaller. Selection to reduce frequencies of cows with deep udders, especially low rear udders, widely placed teats, rear teats too far back, and teats that are short and wide, may augment, modestly, efforts to reduce incidence of mastitis through improved sanitation, antibiotic treatment, and proper milking procedures.

Animals↗

Relationships between somatic cell counts and milk production.

The relationship between Dairy Herd Improvement program test-day milk yield and somatic cell counts in milk was analyzed in 34 dairy herds over 3 yr. Estimates of this relationship were more accurate when somatic cell counts were transformed to natural logarithms rather than actual. For 67,707 observations, test-day milk yield decreased with increasing somatic cell count. The decrease of milk yield for second and later lactations, as somatic cell count increased, was greater than for first lactations. When herds were partitioned according to herd milk production (greater than 7700, 6500 to 7700, and less than 6500 kg/yr), decrease of milk yield was linear with increasing somatic cell counts for herds averaging below 7700 kg milk. Regressions were linear, quadratic, and cubic for both parity groups in herds with high production, over 7700 kg/yr. Quarter samples were composited for each cow and cultured. Percentage of infected cows increased as somatic cell counts increased with greater infection rates above 400 X 10(3).

Animals↗

Effect of an automated bedside dispensing machine on medication errors.

The effect of an automated bedside dispensing machine on medication errors was studied on a 32-bed surgical unit of an 848-bed hospital. The experimental system (McLaughlin Dispensing System) included at each patient's bedside a locked medication cabinet that was electronically programmed to allow the nurse access to doses due at a particular time. The control system was a decentralized unit dose system. A crossover study design with random assignment of subjects and treatments was used. In the 14-day study period, nurses were observed by a pharmacist for 28 five-hour periods as they administered medications on the day and evening shifts. The mean error rates were significantly different--10.6% for the experimental system and 15.9% for the control system. Wrong time errors were the most common type. No significant differences were found between day and evening shifts or workloads of individual nurses. There was no treatment order effect. The error rate was significantly lower for the automated dispensing system than for the system using unit doses dispensed from a satellite pharmacy. Automated dispensing systems may be useful in reducing errors in administration time and dose omissions.

Computers↗

Consultant evaluation of a hospital medication system: analysis of the existing system.

A consultant team's evaluation of a system for distributing and controlling medications in a large teaching hospital is described. Through interviews with key personnel from administration, pharmacy, nursing, and the medical staff, an interdisciplinary research group identified problems in the reliability and response times of the hospital's existing medication system. After assessing staff expectations regarding acceptable standards for medication errors and response times and their attitudes toward proposed changes in the medication system, medication-error rates were determined using a pharmacist-observer method. Observations during 34 five-hour periods on four nursing units were conducted over a 17-day period. Medication-error rates were calculated as the frequency of medication errors during the observation period divided by the total opportunities for error (OE), which were defined as doses ordered plus unauthorized doses given. Response times for processing "now," "stat," and routine orders were also determined using work-sampling methods. The total medication-error rate for the nursing units studied was 9% excluding wrong-time errors; more than a third of doses were given more than 30 minutes before or after their scheduled administration times. Response times for "now" and "stat" orders averaged about 23 minutes, in conformance with the desired standard of 30 minutes. However, processing of routine orders required an average of two hours and seven minutes, much of which was attributed to delays in the messenger service. The basic design of the existing unit dose medication system contributed to problems in the reliability and efficiency of the system.

Attitude of Health Personnel↗

Consultant evaluation of a hospital medication system: synthesis of a new system.

Recommendations of consultants for the implementation of a new medication system at a large teaching hospital are described. Based on a previous analysis of the hospital's existing drug distribution and control system that revealed problems in reliability and response time, an interdisciplinary consultant group offered 14 recommendations, which included implementation of a computerized unit dose delivery system and selected clinical pharmacy services. Functions identified for which computerization would produce the greatest benefits included maintenance of patient census data, medication order entry and retrieval, and preparation of a medication administration record for nursing. Recommendations for improving the unit dose system in the hospital consisted of increasing the number of medications packaged in true unit dose form, increasing the frequency of daily deliveries of scheduled medications, sending p.r.n. medications on an on-call basis, decreasing the lead time for preparation of i.v. solutions, and using a pharmacist-manned portable medication cart to reduce workload on the central pharmacy during peak workload periods. Clinical pharmacy services identified as having the greatest cost-benefit ratio were discharge consults, drug therapy monitoring, and drug-use review. Using information from published studies and cost data from the hospital, a net annual savings of over +152,000 was projected with implementation of these services. Improvements in the unit dose system and implementation of clinical pharmacy services were expected to result in substantial cost savings in the study hospital.

Computers↗

Consultant evaluation of a hospital medication system: implementation and evaluation of the new system.

The effects of consultant-recommended modifications in a hospital medication system on medication-error rates and response times were evaluated. Fourteen recommendations for improving the medication system in a large teaching hospital were implemented to varying extents over a period of 1.5 years. The response times and medication-error rates of the newly implemented system were then measured using pharmacist-observers as was done in the old medication system. Medication-error rates were then compared on one medical-nursing unit and two surgical-nursing units both before and after implementation of the new system on the medical unit alone. Response times for routine medication orders decreased by 55% compared with the previous system; for "now" and "stat" orders, response times were reduced by 57% for orders filled from the central pharmacy and by 70% for orders filled from medication carts on the nursing units. No significant differences in medication-error rates were found when the old and new medication systems were compared. This finding was attributed primarily to the hospital's failure to implement recommendations related to computer printing and sorting of orders, use of dispensing envelopes for delivering medications in true unit dose form, and packaging of all medications in unit dose form. This study illustrates how the benefits of a unit dose system can be compromised in implementation and the need for close monitoring to ensure that performance standards are maintained.

Consultants↗

Milking cows with positive pressure stimulation in late lactation.

Twelve Holstein cows in second halves of lactations were divided into two groups of six each, designated "unstimulated" and "stimulated" groups. Over a preliminary 11 days, all cows were stimulated before each milking by a 1-min hand wash. After this period, premilking preparation and stimulation routines were changed for both groups. The "unstimulated" group was changed to a milking routine that included no premilking udder stimulation. The "stimulated" group was treated for the 1st min after cup application with positive pressure (raising pressure at the pulsator's air vent to about 80 kPa above atmospheric). Both groups of cows were milked twice daily by these two routines for 56 days. "Stimulated" cows showed no significant difference of milk production compared with cows given no premilking udder stimulation. Both average fat percent and milk fat yield was greater for cows given positive pressure than for those receiving no premilking stimulation. Cows given positive pressure stimulation did not differ significantly in protein percentage or production from unstimulated cows, nor did positive pressure stimulation affect machine-on time, residual milk yield, or prolactin or cortisol release. Cows given positive pressure stimulation showed a more rapid rise of concentrations of oxytocin in serum than cows given no stimulation.

Animals↗

Comparison of single- and multiple-trait selected sires--response of heifer growth.

Body weights and linear body measurements were on 386 heifers whose sires were selected according to two criteria: 1) Yield, selection only on milk yield Predicted Difference from daughters' first lactations; 2) Merit, selection on a combination of milk yield Predicted Difference (all daughters), udder type, and percentage of daughters leaving herd in first lactation. No significant differences existed between Yield and Merit heifers for body weights at various ages through first calving or in heart girth or withers height through 18 mo of age. Heifers born to dams first parity were lighter at birth but were not significantly different from other parties of dam for weight, withers height, or heart girth at later ages. Differential selection for milk yield as in this study did not change body weight of heifers.

Aging↗

Methods of estimating energy intake by production traits and body weight.

Relationships among three estimates of energy intake of individual lactations were measured. The study was of 167 Holstein heifers in first lactation fed 1.8 kg of alfalfa hay and one of the two mixed rations of concentrate, corn silage, and grass silage ad libitum. Estimate 1 (Megacalories of net energy for lactation) was calculated from lactation milk yield, mean fat test, mean body weight, change in body weight, and net energy requirements for production, maintenance, and growth from the National Research Council. Estimates 2 and 3 were computed from feed intake of the individual and the National Research Council's estimates of net energy content of individual components of feed. Dry matter for each component of Estimate 2 was constant for the duration of the study, whereas Estimate 3 accounted for weekly variation in dry matter of feeds. Estimate 1 explained 88 and 91% of the variation in Estimates 2 and 3, indicating that accounting for weekly variation in dry matter improved the relationship only slightly. Regressions of Estimates 2 and 3 on 1 were 1.17 and 1.14. An empirical estimate of the net energy requirement for milk protein was 9.7 Mcal of net energy for lactation per kilogram of protein when data were adjusted for year-season of calving. Addition of protein yield to regression models of Estimates 2 and 3 on individual production and weight variables increased coefficients of determination by a maximum of 3%.

Animals↗

Response to selection for milk yield in Holsteins.

Data were collected for 11 yr in five institutional herds in Virginia to determine the response to selection for milk yield and to examine correlated response in other traits. A randombred control population allowed separation of genetic and environmental effects. The genetic base was the same for both control and selection groups, and little directional selection took place in the control population. The control line was generated from 12 sire lines initiated by 8 unproven sires sampled by artificial insemination and sons of 4 proven bulls. Four bulls high for Predicted Difference milk were used in the selection group each year. By three methods of analysis, best linear unbiased prediction, deviation of selection from control group means, and least squares differences between selection and control for milk, fat, and fat percentage were: 370, 374, 438 kg; 10, 8, 6 kg; and -.02, -.02, and -.10%. These agree closely with expectations from modified contemporary comparisons of the bulls. Differences in fat percentages were more variable although all analyses indicated a negative correlated response to selection for milk yield. Generation effects varied with method of analysis but were generally small and agreed with differences in sire Predicted Differences. Response differed across herds.

Animals↗

Medication errors in nursing homes and small hospitals.

An observation method for measuring the rate of medication errors, which can be used as an outcome indicator of a medication system's quality, was evaluated in a national sample of long-term care facilities (LTCFs) and small hospitals. Trained nurse and pharmacist observers observed nurses administer medications during the three-hour period surrounding the peak medication workload on one day in national sample of 58 LTCFs and 10 hospitals. Opportunity-for-errors (OE), defined as the total number of doses ordered plus the unauthorized doses given, were counted, as well as all medication errors. The error rate was calculated as the proportion of errors in total OEs. The reliability of the method was evaluated on seven days by comparing the results of a researcher and observer, who were observing the same nurse. The mean-medication-error rate was 12.2 and 11.0% in the LTCFs and hospitals studied, respectively. Three LTCFs and four hospitals had error rates of zero. Only 31% of the LTCFs and 40% of the hospitals would pass a medication-error limit standard of 6%. The authors concluded that the observation method was promising. Recommendations for further study included: (1) implementation of a one-year project to evaluate observer efficiency after becoming proficient with the method, (2) improvement of the reliability measure, and (3) examination of the relationship of medication errors with structure and process variables.

Hospital Bed Capacity, 100 to 299↗

Drug information services activity, 1961-1979: a citation analysis.

In an attempt to determine the interrelationships of articles published regarding drug information services activity, a citation analysis was performed. The period chosen for study was 1961-1979. During this period, some 258 publications were identified as meeting the operational definition of drug information services activity. A subset of publications was selected for further study and showed that (1) less than 1/3 of the articles in the subset cited one another, (2) the "classic" article(s) are seldom cited, and (3) authors tend to cite themselves more frequently than others. A historiograph is presented which shows all of the citation interrelationships of the subset of publications.

Abstracting and Indexing↗

Variation in Wisconsin Mastitis Test Scores of bucket milk samples and relationship to bacterial infections.

Sources of variation in the Wisconsin Mastitis Test were studied in 4739 bucket milk samples from 111 cows in one herd during 103 days. Quarters of cows were classified infected or uninfected through bacteriologic assays of quarter milk samples. Quarters were uninfected in 70.4% of the cow-quarter-days and infected with Staphylococcus aureus and Streptococcus agalactiae in 1.4 and .9% of the quarter samples. Scores of all cow-days averaged 8.5. Wisconsin Mastitis Test scores of cow-days having no pathogens averaged 5.8. Correlation of duplicate samples was .97. Repeatability of monthly tests was .67. Days within month of lactation, month within age group, cow within age, and age differed. Older cows averaged higher Wisconsin Mastitis Test scores. Scores for uninfected cow-days did not differ with age. Scores were higher by 5.5 units in cows with infected quarters than in those with no infected quarters. The increase was greater with S. aureus or S. agalactiae present than with less virulent pathogens. In a cost-utility analysis, Wisconsin Mastitis Test was inefficient in detecting infected cows with a single test.

Animals↗