PubMed Health⌕ Search

Biomedical subjects

R J Emery

Publications and source records attributed to R J Emery.

At least 37 records · Page 2Linked to original sources
PubMed2000

Radioactive waste minimization implications of clinically-indicated exsanguination procedures.

Exsanguination is a method of animal euthanasia approved for use in specific circumstances. Animals undergoing exsanguination are fully anesthetized, and the blood is removed resulting in hypovolemia. In situations where radioactive materials are used as part of a research protocol that remain predominantly suspended in the blood, the exsanguination procedure can result in a significant lowering of residual radioactivity content. This reduction can greatly affect the types of waste management and minimization options that can be subsequently applied. In this study, data were collected from 20 rabbits injected with approximately 29.6 MBq (0.8 mCi) of tritiated thymidine as part of a percutaneous transluminal carotid artery angioplasty study. Residual concentrations of radioactivity were consistently reduced by an average of 88%. The reduction was very significant in this instance, since the residual activities were below the established exemption limit of 1.85 kBq g(-1) (0.05 microCi g(-1)) for disposal of these wastes as non-radioactive. Although the exsanguination procedure can result in significant waste minimization opportunities in certain circumstances, this should not be the rationale for its use. Rather, the method of euthanasia should be based exclusively on sound animal care and use principles, and waste management strategies should then be made following that decision. Health Phys. 79(3):291-293; 2000 Key words: waste, low-level; waste management; radiation protection; blood

Animals↗
PubMed2000

Anticipating and addressing workplace static magnetic field effects at levels <0.5 mT.

Magnetic resonance, once a research tool limited to the basic sciences, has experienced an increase in popularity due to its unique ability to analyze certain living systems in vivo. Expanding applications in the biomedical sciences have resulted in magnetic sources being located in research institutions nationally. Space and resource limitations sometimes necessitate siting magnetic resonance units in proximity to other institutional operations. For magnetic field shielding and personnel protection considerations, the generally accepted 0.5 mT (milliTesla) limit for implanted cardiac devices is commonly used as the conservative basis for decisions. But the effects of magnetic fields on equipment can be easily observed at levels far below 0.5 mT, often resulting in concern and apprehension on the part of personnel in the surrounding areas. Responding to recurrent worker concerns spawned by noticeable effects on equipment at exposure levels <0.5 mT can strain finite radiation safety program resources. To enhance the ability to anticipate possible facility incompatibility issues associated with the installation of magnetic sources, a literature review was conducted to summarize documented equipment effects. Various types of equipment were found to be impacted at levels ranging down to perhaps 0.001 mT. Armed with this information, practicing radiation safety professionals can better anticipate facility incompatibility issues and improve their responses to worker concerns initiated by observed effects on equipment.

Humans↗
PubMed2000

The forms and sources of cytokinins in developing white lupine seeds and fruits.

A comprehensive range of cytokinins (CK) was identified and quantified by gas chromatography-mass spectrometry in tissues of and in xylem and phloem serving developing white lupine (Lupinus albus) fruits. Analyses were initiated at anthesis and included stages of podset, embryogenesis, and seed filling up to physiological maturation 77 d post anthesis (DPA). In the first 10 DPA, fertilized ovaries destined to set pods accumulated CK. The proportion of cis-CK:trans-CK isomers was initially 10:1 but declined to less than 1:1. In ovaries destined to abort, the ratio of cis-isomers to trans-isomers remained high. During early podset, accumulation of CK (30-40 pmol ovary(-1)) was accounted for by xylem and phloem translocation, both containing more than 90% cis-isomers. During embryogenesis and early seed filling (40-46 DPA), translocation accounted for 1% to 14% of the increases of CK in endosperm (20 nmol fruit(-1)) and seed coat (15 nmol fruit(-1)), indicating synthesis in situ. High CK concentrations in seeds (0.6 micromol g(-1) fresh weight) were transient, declining rapidly to less than 1% of maximum levels by physiological maturity. These data pose new questions about the localization and timing of CK synthesis, the significance of translocation, and the role(s) of CK forms in reproductive development.

Cytokinins↗
PubMed1997

Acromial morphology: the enigma of terminology.

Variation in acromial morphology has been associated with the pathogenesis of subacromial impingement syndrome and rotator cuff disease. However, the use of a multitude of different descriptive terminology has lead to confusion in the literature concerning acromial architecture. This review is aimed to show the discrepancy in the literature of acromial morphology and advise suitable terminology to prevent confusion in the future.

Acromion↗
PubMed1997

A proposed method to minimize waste from institutional radiation safety surveillance programs through the application of expected value statistics.

Institutional radiation safety programs routinely use wipe test sampling and liquid scintillation counting analysis to indicate the presence of removable radioactive contamination. Significant volumes of liquid waste can be generated by such surveillance activities, and the subsequent disposal of these materials can sometimes be difficult and costly. In settings where large numbers of negative results are regularly obtained, the limited grouping of samples for analysis based on expected value statistical techniques is possible. To demonstrate the plausibility of the approach, single wipe samples exposed to varying amounts of contamination were analyzed concurrently with nine non-contaminated samples. Although the sample grouping inevitably leads to increased quenching with liquid scintillation counting systems, the effect did not impact the ability to detect removable contamination in amounts well below recommended action levels. Opportunities to further improve this cost effective semi-quantitative screening procedure are described, including improvements in sample collection procedures, enhancing sample-counting media contact through mixing and extending elution periods, increasing sample counting times, and adjusting institutional action levels.

Radiation Monitoring↗
PubMed1997

Notices of violation issued to Texas radioactive material licensees inspected in 1995.

Notices of violation stemming from the inspection activities of the Texas Department of Health's Bureau of Radiation Control during calendar year 1995 are summarized and characterized. Although eight distinct general categories of radioactive material licenses were included in the analysis, certain general trends were noted, permitting the formulation of an objective list of the ten most frequent violations cited. In order ranked from the most frequent, these include not following operating or safety procedures, radiation surveys not being performed, inadequate personnel monitoring records, instrumentation not used or out of calibration, radioactive material inventories not performed, leak tests not performed, deficiencies in training for industrial uses, inadequate inspection and maintenance of devices, unauthorized users of radioactive material, and incomplete or absent records for receipt or transfer of radioactive material. Although the analysis was limited to a single state, the results can benefit radiation protection quality assurance programs and health physics continuing education efforts by objectively identifying areas commonly cited for being deficient. The results also reiterate the necessity for proper documentation, as at least seven of the ten most frequent violations issued appear to stem predominantly from the records of radiation protection programs.

Health Physics↗
PubMed1997

A biomechanical evaluation of suture anchors in repair of the rotator cuff.

Repair of the rotator cuff requires secure reattachment, but large chronic defects cause osteoporosis of the greater tuberosity which may then have insufficient strength to allow proper fixation of the tendon. Recently, suture anchors have been introduced, but have not been fully evaluated. We have investigated the strength of suture-to-anchor attachment, and the use of suture anchors in repairs of the rotator cuff either to the greater tuberosity or the lateral cortex of the humerus. The second method gave a significant increase in the strength of the repair (p = 0.014). The repairs were loaded cyclically and failed at low loads by cutting into bone and tendon, casting doubt on the integrity of the repair in early mobilisation after surgery. Repairs with suture anchors did not perform better than those with conventional transosseous attachment.

Aged↗
PubMed1996

Assessing the service provided by an institutional radiation safety survey program.

Routine radiation safety surveys are a required part of every institutional radiation protection program. Although mandated by regulation, surveys are really performed to help clinicians and researchers establish and maintain radiologically-safe working and learning environments. In some cases, however, the priorities established by a radiation protection program may not coincide with the needs perceived by the institution's workers, leading to possible alienation, dissatisfaction, and non-compliance with policies, procedures, and regulations. To determine if a typical survey program was perceived as providing a good or valued service to workers, a simple questionnaire was created and utilized for a 6-mo period The results obtained from this targeted assessment tool indicate that the radiation safety survey services were perceived as useful by most of the workers. In addition, the actual process of comment solicitation provided a positive feedback mechanism from the service recipients to the radiation safety staff, managers, committee members, and institution administrators.

Humans↗
PubMed1995

Simple physical, chemical, and biological safety assessments as part of a routine institutional radiation safety survey program.

To assist in providing comprehensive surveillance for potential health and safety hazards, simple assessments of physical, chemical, and biological safety concerns were incorporated into traditional radiation safety facility surveys for a biomedical research and clinical care facility for a 1-y period. Customized training was provided to radiation safety staff members concerning each of the hazard areas identified and a brief checklist was developed. During the 1-y period 802 laboratory and clinic surveys were performed, and of the 372 safety issues noted by the staff, approximately 55% were identified as not related to traditional health physics surveillance activities. The utilization of these simple safety audit tools as part of a routine radiation safety surveillance program can serve as a cost effective way to assist in maintaining a teaching, research, and clinical environment that is free from a variety of recognized hazards.

Data Collection↗
PubMed1995

Coracoid transposition for recurrent anterior instability of the shoulder. A 20-year follow-up study.

We report the 20-year results of Bonnin's modification of the Bristow-Latarjet procedure in 14 patients operated on by one surgeon. All but one patient had had traumatic dislocations. At review, the Rowe scores were excellent in five, good in eight and fair in one. The functional outcome was satisfactory, with a mean Constant-Murley score of 80 points (68 to 95), but 12 patients had restriction of external rotation (86%). There were radiological degenerative changes in ten shoulders (71%): six in Samilson grade I, one in grade II, and three in grade III. Isometric power was considerably reduced in patients with grade-III degenerative change. This operation provides good long-term shoulder stability, but the high incidence of radiological degenerative change is a cause for concern.

Adult↗
PubMed1993

The shoulder in sickle-cell disease.

Sickle-cell disease (SCD) is probably the commonest cause of avascular necrosis worldwide, and its prevalence appears to be rising in developed countries. Avascular necrosis of the humeral head is a common complication but has not been previously studied in detail. We have reviewed 138 patients with SCD for clinical, radiological and functional abnormalities of the shoulder, using a radiological classification designed for avascular necrosis of the shoulder. Radiographic lesions, frequently bilateral, were found in 28% and only 53% of patients had normal shoulder function. The management of this relatively common complication is difficult. Joint replacement is likely to fail and early diagnosis is important.

Adolescent↗
PubMed1992

Cemented versus uncemented femoral components in the ring hip prosthesis.

A prospective, randomised and independently assessed trial of the Ring UPM total hip replacement showed that the quality of the early result was better if the femoral prosthesis was cemented than if it was not. More patients with cemented prostheses were painfree at four months (58% cemented:42% uncemented) and at one year (63% cemented:50% uncemented), but at two years pain relief was equal in both groups. At two years significantly more patients with cemented prostheses could walk without support (96% cemented:62% uncemented, p = 0.01 to 0.05). There is a need for more similar trials to compare the results of contemporary designs of cemented and uncemented total hip prostheses.

Activities of Daily Living↗
PubMed1991

First metacarpal osteotomy for carpo-metacarpal osteoarthritis.

The results of basal osteotomy of the first metacarpal in the treatment of carpo-metacarpal osteoarthritis have been analysed from two small studies, one retrospective and one prospective. Assessment included clinical examination, standardised radiography and computerised pinch-grip analysis. Surgery reduces the subluxation at the first metacarpal base and provides good pain relief and restoration of function in the majority of cases. It is concluded that this relatively simple technique produces very good results without reducing power grip.

Aged↗