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Biomedical subjects

W J Russell

Publications and source records attributed to W J Russell.

At least 91 records · Page 5Linked to original sources
PubMed1990

Cardioprotection by Cu,Zn-superoxide dismutase is lost at high doses in the reoxygenated heart.

Limited dose-response curves for superoxide dismutase (SOD) were assessed in isolated and in vivo hearts. SOD at 2.3, 7, 20, or 50 mg/L suppressed CK release in Langendorff rat hearts by 61%, 63%, 72%, and 30%, respectively. SOD at 0.5, 1, 5, and 50 mg/L suppressed LDH release in Langendorff rabbit hearts by 32%, 48%, 54%, and -12%, respectively. In rabbit hearts subjected to coronary artery ligation and reperfusion in vivo, SOD at 2, 5, or 15 mg/kg reduced infarct size by 10%, 30% or 19%, respectively, while 50 mg/kg increased infarct size by 28%. In conclusion, while SOD was protective at low doses in all models, protection was lost at higher doses in the isolated rat and rabbit hearts, and exacerbation of damage was seen in the in vivo rabbit hearts.

Animals↗
PubMed1990

The stability of atracurium in clinical practice.

Atracurium has an unusual intrinsic Hofmann elimination which is increased by an alkaline environment and increased temperature. Normally the relaxant is stored at pH 3.3 and kept at a temperature of 4 degrees C. However, it is convenient to have a reasonable quantity available within the operating theatre. This study examined the rate of degradation of atracurium in the operating theatre environment of 20 degrees C. Atracurium within one month of its expiry date was placed in the drawer for anaesthetic drugs in each of three operating theatres. At the end of each month, further drug was added to the stock. At the end of the study, atracurium which had been stored continuously at 4 degrees C, was at 102.9% of nominal strength, having started with 113.5% at manufacture. Atracurium which had been at room temperature for one, two and three months respectively retained 99%, 95% and 92% strength respectively. These results show that even three months' exposure to room temperature does not cause enough deterioration to be clinically significant.

Atracurium↗
PubMed1989

Dental radiography exposure of the Hiroshima and Nagasaki populations.

Dental radiography doses in Hiroshima and Nagasaki were estimated on the basis of survey data from dental hospitals and clinics in Hiroshima and Nagasaki, and doses were measured by thermoluminescent dosimeters and a phantom. Doses to organs, including the lens, pituitary fossa, thyroid gland, and skin were calculated from data obtained during a 2-week survey in both cities. The mean caput doses were calculated from the data indicating frequency per year and were tabulated by organs, age, teeth examined, type of examination, population, sex, and city. No significant difference was observed by age, population, sex, or city. Currently the doses incurred during dental radiography may not be sufficiently high to cause bias in the assessments for late radiation effects among atomic-bomb survivors. However, the mean caput thyroid doses of 62 mrad and 67 mrad in Hiroshima and Nagasaki, respectively, cannot be ignored from the standpoint of their potential in contributing to radiation-induced carcinogenesis.

Adolescent↗
PubMed1989

Oropharyngeal volumes.

The volume of the mouth and pharynx was measured in 20 cadavers and ranged from 25 to 202 ml with a median value of 87 ml, a mean of 90.7 ml and a geometric (logarithmic) mean of 78.3 ml. The volume that encompasses 99% of the normal population is estimated as 215 ml if the assumption of a normal Gaussian distribution is made, or 342 ml [corrected] if a log-normal distribution is assumed. Collection containers in suction equipment intended for removing vomit from the pharynx and mouth in adults should have a useable volume of at least 500 ml.

Adolescent↗
PubMed1989

Influence of blood storage time and plasma histamine levels on the pattern of transfusion reactions.

The data from 359 transfusion reactions reported over a 3-year period have been compared with those obtained from 359 matched units given at the same time as the former but not implicated in a reaction. It was found that patients who developed reactions which were not accompanied by a change in body temperature received units with a longer storage time than patients experiencing febrile reactions. In addition it was noted that reactions which included a skin rash also tended to be associated with units stored for longer. In a further prospective assessment plasma histamine levels were measured in a group of 71 patients experiencing 'anaphylactoid', febrile and mixed transfusion reactions as well as in individuals in whom blood transfusions did not cause a reaction. The 'anaphylactoid' reaction group demonstrated a mean plasma histamine level in excess of 1 ng/ml, whereas mean concentrations below 0.50 ng/ml were recorded in the other 3 groups. Our data also suggested that in general, more and 'older' blood was given to the 'anaphylactoid' reactors. The high plasma histamine concentrations could readily contribute to the rash, wheeze and flushing recorded in these individuals. Thus, if a long shelf-life for stored blood is required, strategies which remove histamine from the unit may be worth considering.

Blood Preservation↗
PubMed1989

Extra-adrenal phaeochromocytoma: report of three interesting cases.

The clinical, laboratory and operative findings from three cases of extra-adrenal phaeochromocytoma are reviewed. Some of the difficulties encountered in localizing such a neoplasm are highlighted. Data from intraoperative catecholamine monitoring on the three patients are also presented. Adequate alpha and beta blockade produced stable cardiovascular parameters during surgery in all three individuals.

Abdominal Neoplasms↗
PubMed1989

A simple technique for diagnosing oesophageal intubation.

Undiagnosed oesophageal intubation during anaesthesia is a major cause of anaesthetic-related morbidity and mortality. A test was devised and evaluated to distinguish between placing an endotracheal tube in the trachea and in the oesophagus. The test involves threading a lubricated nasogastric tube through the endotracheal tube, applying continuous suction to the nasogastric tube and then attempting to withdraw the nasogastric tube. Four aspects distinguish an endotracheal tube in the trachea from one in the oesophagus: 1. the length of nasogastric tube inserted and the feel of the final obstruction to further insertion. 2. the ability to maintain unobstructed suction through the nasogastric tube, 3. the ease of withdrawal of the nasogastric tube during continuous suction, 4. the nature of any aspirate (i.e. mucus or gastric contents). An evaluation was performed on twenty patients in whom both the trachea and oesophagus were intubated simultaneously. In all twenty cases, each of the two endotracheal tubes was correctly identified as being either tracheal or oesophageal. The ability to maintain suction and the ease of withdrawal most clearly distinguished between the two positions.

Adult↗
PubMed1989

Ultrasonography of benign gastric ulcers. Characteristic features and sequential follow-ups.

Ultrasonography was performed for 15 patients with gastric ulcers, after tap water ingestion using 5-MHz and/or 7.5-MHz transducers. Sonographic signs of gastric ulcer were classified as gastric wall edema associated with ulcer crater (six cases) and gastric wall edema only (nine cases). The latter nine included two cases of perforation of gastric ulcers that were depicted as gastric wall edema associated with fluid collection. Ultrasonography proved useful for detecting benign ulcerations and can be used to supplement follow-up examinations, but it cannot replace endoscopy and contrast radiography.

Adult↗
PubMed1988

Para-acetabular periarthritis calcarea: its radiographic manifestations.

On retrospective reviews of radiographs, periarthritis calcarea was distinguished from os acetabula by interval radiographic progression and regression. Among 59 men and 51 women, there were 137 instances of para-acetabular calcifications and ossifications, which were morphologically classified as 58 discrete, 58 amorphous, and 21 segmented types. Correlations with other radiographic abnormalities, symptoms, signs, and laboratory abnormalities were sought, but not established. Out of 93 serially imaged opacities, 90 changed, including 37 of the 40 instances (92.5%) of the discrete type and 53 instances (100%) of the amorphous and segmented types--due to periarthritis calcarea. At least 43 of 90 densities were newly developed. Mean age at first detection was 47.7 years. Three of the discrete densities were unchanged and represented os acetabula. Thus, recognition of para-acetabular periarthritis calcarea is not only of academic importance; it can facilitate proper treatment as well.

Acetabulum↗
PubMed1988

Pharmacokinetics of a new sublingual formulation of temazepam.

The pharmacokinetics of a new 10 mg sublingual tablet formulation of temazepam and those of a currently marketed 10 mg oral capsule formulation were evaluated in a group of ten healthy volunteers. No significant differences were observed between the two formulations with respect to any of the pharmacokinetic parameters assessed. Lethargy and somnolence were reported on both capsule and tablet by several subjects at a time which corresponded with the maximum concentration of drug in plasma. The data indicate that the sublingual tablet and orally administered capsule have a similar pharmacokinetic and pharmacodynamic profile.

Administration, Oral↗
PubMed1988

Soft X-ray dosimetry and RBE for survival of Chinese hamster V79 cells.

Dosimetry and biological effects of 40 and 50 keV low-energy X-rays generated by a SOFTEX Model CMBW-2 apparatus were studied. Doses were measured using a thin-window parallel-plate ionization chamber; beam quality was assessed using aluminum absorbers; exposure rates per unit current were determined according to the X-ray tube current and exposure times; and thermoluminescent (BeO chip) dosimeters were used to ascertain dose distributions in the irradiation field. The average correction factors for nonuniformity were calculated from the measured dose distributions. The means for ascertaining accurate exposures and doses using these methods are discussed. The dose-survival relationship of Chinese hamster V79 cells were assessed by irradiating them with 40 and 50 kV soft X-rays, 180 kV X-rays, and 60 Co gamma rays. Soft X-rays with three distinct effective energies were tested by changing the tube voltage kV and aluminium filter thicknesses; namely (1) 40 kV without filter, (2) 40 kV with a 0.2 mm thick aluminium filter and (3) 50 kV with a 0.7 mm thick aluminium filter. The effective energies obtained according to attenuation measurements using aluminium for these soft X-rays were 8.1, 11.7 and 18.5 kV, respectively. In this study the relative biological effectiveness (RBE) at 10 per cent survival compared with 60Co gamma rays ranged from 1.5 to 1.6. The RBE of 180 kV X-rays relative to 60Co gamma rays was 1.29. This study provided experimental data for the RBE of V79 cells in the intermediate energy range between hard and ultrasoft X-rays, data for which were previously reported by Goodhead and co-workers (1977, 1979, 1981).

Aluminum↗
PubMed1988

Medical x-ray exposure doses as contaminants of atomic bomb doses.

Since 1967 at the times of their biennial ABCC/RERF radiological examinations, all Adult Health Study (AHS) subjects have been interviewed to determine the exposures to medical x-rays they experienced in institutions other than RERF in order to estimate the numbers of examinations and corresponding doses which they received. These data have been stored on computer tapes together with the doses these subjects received during their radiological examinations in the ABCC/RERF Department of Radiology. Thus, their medical x-ray doses are available along with their atomic bomb doses (tentative 1965 doses revised, T65DR) for assessment of the role of ionizing radiation in the development of diseases. The medical x-ray doses incurred at RERF were assessed by means of phantom dosimetry. Those at other institutions were determined using phantom dosimetry data and results of surveys for trends in radiological examinations in Hiroshima and Nagasaki. By the end of 1982, the average medical x-ray doses to the active bone marrow were 12.04 mGy for A-bomb exposed groups and 8.92 mGy for control groups (not-in-cities); to the male gonads, 2.26 mGy and 1.89 mGy, respectively; and to the female gonads, 17.45 mGy and 12.58 mGy, respectively. Results for Hiroshima and Nagasaki were similar. The main impact of medical x-ray doses was in the lowest T65DR group. Medical x-ray active bone marrow doses ranged from 0.05-500% (mean, 35%) of A-bomb doses in the 10-99 mGy T65DR group. In the 100-999 mGy T65DR group, medical x-ray active bone marrow doses ranged from 0.005-50% (mean, 5%) of their T65DR. In the greater than 1,000-mGy T65DR group, medical x-ray exposures were proportionally less. Female active bone marrow and gonad doses were similar in magnitude to the male active bone marrow doses. Medical x-ray exposures produced smaller doses to the gonads of males than to those of the females. The use of medical x-rays is steadily increasing. Careful consideration of doses from medical sources is essential for reliable assessments of the effects from exposures to the atomic bombs.

Adult↗
PubMed1988

The prevention of gastric inflation--a neglected benefit of cricoid pressure.

The ability of cricoid pressure to prevent inflation of the stomach during mask ventilation of a patient was studied. Fifty patients were randomly allocated to either have or not have cricoid pressure applied during a three-minute period of standardised mask ventilation. Patients who had had cricoid pressure applied had less gas in the stomach after mask ventilation (P less than 0.001). However, in a subgroup of patients considered difficult to ventilate, cricoid pressure seemed less successful in preventing gastric inflation. Cricoid pressure is a useful technique for reducing gastric inflation during mask ventilation, particularly in patients who are relatively easy to ventilate.

Cricoid Cartilage↗
PubMed1988

Muscle strength following anaesthesia with atracurium and pancuronium.

Postoperative recovery from muscle weakness was investigated by handgrip strength after general anaesthesia using short- and long-acting muscle relaxants. Handgrip strength was measured on four occasions, preoperatively, before and after premedication, and postoperatively, both as soon as the patient could sustain a five-second headlift and one hour later. Twenty patients received either atracurium 0.6 mg/kg or pancuronium 0.1 mg/kg as part of a general anaesthetic technique with neostigmine reversal. Compared with their initial preoperative hand strengths, the two relaxant groups showed only an insignificant decrease in grip strength to 92% after premedication. Postoperatively when a five-second headlift was achieved, the patients in both groups were weak. The group given atracurium had a mean of 60% of their initial grip strength and those given pancuronium had a mean of 44%. This difference in strength was statistically significant from the initial level and from each other. However, there was no difference between the groups in the time interval from administering reversal to achieving a sustained headlift. One hour later in both groups grip strength was much better, within 80% of that seen after premedication in most patients, and no significant difference in grip strength was seen between the groups. This study demonstrates that patients who receive relaxant anaesthesia have substantial muscle weakness in the recovery phase. When neostigmine reversal is used, pancuronium appears to have a similar return of voluntary muscle power to that seen with atracurium. The marked difference in elimination kinetics of these two relaxants seems to be of little importance when neostigmine reversal is used.

Adult↗