PubMed HealthSearch

Biomedical subjects

C James

Publications and source records attributed to C James.

At least 19 recordsLinked to original sources

Effects of misoprostol on the pharmacokinetics of indomethacin in human volunteers.

The effects of misoprostol (200 micrograms as a single dose or q.i.d. as a multiple dose) on the pharmacokinetics of indomethacin (100 mg single-dose administration or 50 mg t.i.d. multiple-dose administration) were studied in 16 healthy human volunteers under single-dose and steady-state conditions in a randomized, double-blind, placebo-controlled, balanced three-period study design. The overall absorption as shown by the values for area under the concentration curve of indomethacin was unaffected by concurrent administration of misoprostol. However, misoprostol did significantly enhance the steady-state maximum concentration of indomethacin by 32%. Thus misoprostol does not interfere with the absorption of indomethacin despite the known inhibitory effects of this protaglandin analog on acid secretion.

Administration, Oral

General practitioners' confidence in diagnosing and managing eye conditions: a survey in south Devon.

In order to open dialogue aimed at increasing eye care in general practice and reduce waiting times for ophthalmic outpatient appointments general practitioners in the Torbay health district were asked about their levels of confidence in ophthalmology as a subject, and in the diagnosis and management of specific eye conditions. They were also asked about ophthalmic equipment available to them, their management policies for 34 specific eye conditions, and their perceived need for further training in this subject. A total of 75% of the general practitioners responded to the questionnaire. Despite more than half of the general practitioners indicating that they did not feel confident with ophthalmology generally, most expressed confidence in diagnosing and managing common eye conditions. Basic equipment for examining the eye was available to most doctors. Referral policies varied considerably, and these have resource implications. Seventy eight per cent of respondents were prepared to take on more eye care in general practice, and over 80% of general practitioners requested informal teaching sessions in ophthalmology. Support must be forthcoming if general practitioners are to provide eye care in general practice.

Clinical Competence

Intraoperative management of ureteral injury during operative laparoscopy.

Injury to the ureter from operative laparoscopy is rare. The diagnosis is usually made radiologically, in the postoperative period, when the patient presents with symptoms and signs suggestive of ureteral injury. We report herein a case of ureteral injury resulting from operative laparoscopy for endometriosis. The injury was diagnosed and treated via laparoscopy during the same procedure. The increased utilization of operative laparoscopy to perform more complex procedures increases the potential for operative injury to the ureter. Prior visualization or retroperitoneal dissection of the ureter, in appropriate cases, will help reduce this complication and/or permit a prompt diagnosis in the event of such injury.

Adult

Sternomastoid muscle twitch maximum relaxation rate: prolonged slowing with fatigue and post-tetanic acceleration.

1. The maximum rate of relaxation of stimulated twitches (twitch maximum relaxation rate) of the sternomastoid muscle was compared with its frequency-force curve (expressed as the ratio of force produced at a stimulation frequency of 20 Hz to that produced at 50 Hz, the 20:50 ratio) before and after fatiguing exercise of the sternomastoid muscle in 10 normal subjects. The mean (+/- SEM) fresh state twitch maximum relaxation rate was 9.51 (+/- 0.64)% force loss/10 ms and the mean (+/- SEM) 20:50 ratio was 73.4 (+/- 2.6)%. 2. The mean twitch maximum relaxation rate fell to 71.5 (+/- 2.2)% of the pre-fatigue value at 2 min after exercise, recovering to 73.1 (+/- 1.6)% by 5 min, 78.4 (+/- 2.34)% by 10 min and 80.6 (+/- 2.70)% by 60-min. The 20:50 ratio fell to 72.3 (+/- 3.56)% of pre-fatigue levels at 10 min after exercise and recovered to 78.8 (+/- 3.16)% by 60 min. There was no significant difference in the percentage falls between the two techniques. 3. Further studies were performed to determine the response of the twitch maximum relaxation rate to a prior brief tetanic stimulus or a brief maximal voluntary contraction of the muscle. Both tetanic stimulation and maximal voluntary contraction accelerated the twitch maximum relaxation rate to over 140% of the fresh state value. Both manoeuvres temporarily returned the slowed twitch maximum relaxation rate after fatiguing exercise back to the fresh state value. 4. The effect of fatiguing exercise on the time course of recovery of quadriceps twitch maximum relaxation rate was also studied in two subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

A double-blind trial of zinc supplementation in pregnancy.

A double-blind randomised trial of oral zinc supplementation was carried out during the last two trimesters of pregnancy. Fifty-six women at risk of delivering a small-for-gestational-age baby received either zinc supplement (22.5 mg daily) or placebo. Twenty-nine of the women were compliant. Zinc significantly reduced the incidence of intrauterine growth retardation, and most measured indices of labour and fetal health were better in the supplemented group. Larger studies are now needed to confirm a role for selective zinc supplementation in at-risk pregnancies.

Administration, Oral

Measurement of protein biomass by Fourier transform infrared-photoacoustic spectroscopy.

A relatively new analytical technique, Fourier transform infrared-photoacoustic spectroscopy (FTIR-PAS), provides spectra of bacteria, fungi, and other microorganisms in solid states not suitable for conventional absorption spectroscopy. In this paper the feasibility of quantitative measurement of protein biomass on solid substrates by FTIR-PAS is examined and discussed. By measuring photoacoustic absorption bands from amide groups in the protein of microorganisms, the increase in biomass that occurs during growth was monitored directly and accurately. Incorporation of polyacrylonitrile into the sample as an internal standard was shown to be a convenient method for improving both the reliability and the range of detection by photoacoustic spectroscopy. Results of FTIR-PAS measurements of known quantities of microbial mass in simulated growth experiments suggest that the technique may be especially suitable for assays of microorganisms used in solid-state biosyntheses of drugs, hormones, and other biological agents.

Acoustics

The eastern Cree bush-kit program evaluation; its usefulness.

In 1982 the Cree Board of Health and Social Services of James Bay in northern Quebec created the bush-kit program to provide hunters and trappers with the technical skills to handle medical problems in the bush. A formative evaluation of the program revealed a decrease in calls and in medical evacuations from the bush and high levels of satisfaction among the participants, health professionals and community leaders. However, specific service accessibility problems were identified at the time of the evaluation as indicated by participation rates of only 50% of the targeted hunters and trappers. These findings as well as discussions with bush-kit administrators led to subsequent improvements in the program and an increased participation rate the following year.

Community Health Workers

Training perception of acute airflow obstruction.

Ten asthmatics selected for their tendency to experience frequent acute exacerbations were instructed in peak flow measurement. Each subject then recorded estimated peak flow (EPF) and measured peak flow (PF) at home twice daily. Data for up to 56 consecutive observations (4 weeks) per subject were analyzed. The correlation coefficient between EPF and PF following PF drops of 15% was .993 overall and was not significantly different following PF drops even greater than 25%. The absolute and proportional differences between PF and EPF were also not significantly affected by the magnitude of PF drop but decreased over time indicating improved accuracy of estimates with practice. Asthmatics can be trained to estimate accurately acute drops in airflow. Such ability has not been demonstrated in prior studies which utilized verbal symptom reports as indicators of subjective perception of airflow. Accurate perception would be a useful aid in achieving early recognition of acute exacerbations and in improving medication compliance. It is an adjunct to regular peak flow measurement, not a substitute for it.

Airway Obstruction

Antimyosin imaging in acute transmural myocardial infarctions: results of a multicenter clinical trial.

Murine monoclonal antimyosin antibody has been shown experimentally to bind selectively to irreversibly damaged myocytes. To evaluate the safety and efficacy of monoclonal antimyosin for identifying acute transmural infarction, 50 patients with acute Q wave myocardial infarction were entered into a phase I/II multicenter trial involving three clinical sites. Indium-111 antimyosin was prepared from an instant kit formulation containing 0.5 mg of diethylene triamine pentaacetic acid (DTPA)-coupled Fab fragment (R11D10) and 1.2 to 2.4 mCi of indium-111. Average labeling efficiency was 92%. Antimyosin was injected 27 +/- 16 h after the onset of chest pain. Planar or tomographic imaging was performed 27 +/- 9 h after injection in all patients, and repeat imaging was done 24 h later in 39 patients. Of the 50 patients entered, 46 showed myocardial uptake of antimyosin (sensitivity 92%). Thirty-one of 39 planar scans performed at 24 h were diagnostic; 8 showed persistent blood pool activity that cleared by 48 h. Focal myocardial uptake of antimyosin corresponded to electrocardiographic infarct localization. No patient had an adverse reaction to antimyosin. In addition, 125 serum samples, including 21 collected greater than 42 days after injection, were tested for human antimouse antibodies, and all samples were assessed as having undetectable titers. Intensity of antimyosin uptake was correlated with infarct location and the presence or absence of collateral vessels. There was a significant correlation between faint uptake and inferoposterior infarct location. In 21 patients who had coronary angiography close to the time of antimyosin injection, there was a significant correlation between faint tracer uptake and closed infarct-related vessel with absent collateral flow.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

The identification, molecular cloning and characterisation of a gene from Phanerochaete chrysosporium that shows strong homology to the exo-cellobiohydrolase I gene from Trichoderma reesei.

We have identified a genomic DNA fragment from the lignin-degrading fungus Phanerochaete chrysosporium (P.c.) that hybridizes to a DNA probe encoding part of the exo-cellobiohydrolase I (CBHI) gene of Trichoderma reesei (T.r.). This fragment has been subcloned and its nucleotide sequence determined. We demonstrate that it could encode a 516 residue protein that shows strong homology with the known protein sequence of CBHI from T.r. Comparison of the two nucleotide sequences identifies two regions within the P.c. sequence that are not represented in T.r. Further inspection of these regions reveals sequences closely related to the conserved elements of filamentous fungal introns. We conclude that the P.c. genomic sequence contains the same number of introns (2) as found in T.r. but that these are located at different relative positions within the two genes. The transcript from the P.c. sequence is induced in the presence of cellulose but not by glucose and we therefore conclude that this sequence represents the first cellulase gene to have been described from this organism.

Amino Acid Sequence

PAF binding sites. Characterization by [3H]52770 RP, a pyrrolo[1,2-c]thiazole derivative, in rabbit platelets.

52770 RP, the N-(3-chlorophenyl)-3-(3-pyridinyl)-1H,3H-pyrrolo[1,2-c]thiazole -7-carboxamide, displaces in a potent, specific and competitive manner [3H]PAF from its binding sites on rabbit platelets. Since 52770 RP is not structurally related to PAF and has low liposolubility with respect to PAF, it was selected as a potential radioligand for PAF receptor sites. [3H]52770 RP displayed high-affinity, specificity, as well as saturable and displaceable binding to a single class of recognition sites in intact platelets and crude platelet membranes. In these preparations, the values of binding parameters were, respectively, 8.5 and 7.6 nM for Kd, 0.2 pmol/5 X 10(7) platelets and 3.66 pmol/mg protein for Bmax and 0.96 and 0.91 for nH. Inasmuch as the (+)-52770 RP was 300-fold more potent than the (-)-isomer at displacing [3H]52770 RP in intact platelets, the studied binding site manifested stereospecific discrimination. A variety of pharmacological agents including pro- and anti-aggregant compounds did not exhibit affinity for [3H]52770 RP binding sites. In contrast, PAF, some of its active analogues and several recognized PAF antagonists (BN 52021, brotizolam, L-652,731, triazolam), displaced the [3H]52770 RP binding. Studies carried out using [3H]PAF demonstrated that 52770 RP was approximately 4- and 200-fold more potent than L-652,731 and BN 52021 respectively, as a PAF-receptor antagonist. In washed rabbit platelets, the rank order of potency (Ki) for several analogues of 52770 RP, to displace [3H]PAF from its binding sites, was highly correlated (r = 0.96) to their ability to antagonize [3H]52770 RP binding. In functional studies, 52770 RP antagonized not only the PAF-induced aggregation in washed rabbit platelets but also the hypotension evoked by PAF in the anesthetized rat. In this respect, it was 26 and 2 times more potent than L-652,731, respectively. In conclusion, [3H]52770 RP might represent a novel interesting tool for furthering our understanding of the role of PAF binding sites in pathophysiological processes.

Animals