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Biomedical subjects

M McDonald

Publications and source records attributed to M McDonald.

At least 127 records · Page 7Linked to original sources
PubMed1989

A phase I study of immunostimulation and toxicity in patients with colorectal carcinoma using the immunomodulator 3,6-bis(2-piperidinoethoxy) acridine trihydrochloride (CL 246738).

Seventeen patients with residual or recurrent colorectal carcinoma were given a new synthetic immunomodulator [3,6-bis(2-piperidinoethoxy) acridine trihydrochloride CL246738) as part of a phase I clinical trial. No patients had undergone previous immunotherapy or chemotherapy. Detailed immunological studies including interferon levels, interleukin 2 levels, natural killer cell function, mitogen responses of lymphocytes, immunoglobulin levels and lymphocyte subpopulation levels were analysed in the patients who received this drug in an attempt to find out whether there was any biological activity identifiable in humans. None of the subjects showed any significant increases in post treatment values of the immunological parameters studied. Toxic effects of the drug at high doses included nausea, diarrhoea and decreased levels of consciousness. In conclusion, no immunological effects were identified following the administration of CL 246738 in human subjects with recurrent or residual colorectal cancer.

Acridines↗
PubMed1989

Comparison of four methods of assessing visual acuity in young children.

The purpose of this study was to determine which of four tests, the Acuity Cards, the Dot Visual Acuity test, the Broken Wheel test, or the American Optical (AO) pictures, might be most useful for clinical assessment of visual acuity in 2- and 3-year-olds. Data related to clinical utility including success rates, required test times, reliability, and acuity norms were collected. High success rates and short test times support use of the Acuity Cards for 2-year-olds. For testing 3-year-olds a measure of recognition acuity, the Broken Wheel test, may be most useful.

Adult↗
PubMed1989

Cardiovascular actions of human endothelin in conscious sheep.

1. Synthetic human endothelin was injected intravenously over the range 1.5-50 micrograms to examine its cardiovascular actions in conscious sheep. 2. Mean arterial pressure increased by 9-21 mmHg within 30-120 s over the range 5-50 micrograms endothelin. The increase in blood pressure was associated with increased calculated total peripheral resistance and a fall in cardiac output and heart rate. Stroke volume was increased. 3. Injection of endothelin into ganglion blocked sheep produced vasoconstriction and an increased blood pressure response associated with an attenuation of the effects on cardiac output, heart rate and stroke volume. 4. This study suggests that endothelin produces potent arterial vasoconstriction and reflex mediated effects on the heart in conscious sheep.

Animals↗
PubMed1989

Calcium ionophore and acetylcholine dilate arterioles on the mouse brain by different mechanisms.

Pial arterioles on the surface of the mouse brain were observed in vivo under a chamber with a glass window. When placed under the window, calcium ionophore, acetylcholine, and previously acidified sodium nitrite each dilated the arterioles. If the cyclooxygenase inhibitors indomethacin or acetylsalicylic acid were first placed in the chamber, subsequent dilation of the arterioles by calcium ionophore was reduced to essentially zero. Similar blockade of cyclooxygenase failed to significantly reduce dilation by acetylcholine or sodium nitrite. We have previously shown that dilations by calcium ionophore and acetylcholine were endothelium dependent. Our present experiments show that the endothelium-dependent mechanism for dilation by calcium ionophore is cyclooxygenase dependent, while that for acetylcholine is not. This implies that, in pial arterioles, the endothelium-derived relaxing factor for acetylcholine differs from that for calcium ionophore. This agrees with data from other microvascular beds.

Acetylcholine↗
PubMed1989

Comparison of ceftriaxone with cefotaxime in serious chest infections.

Ceftriaxone is a new, third-generation cephalosporin that, because of its long half-life, offers potential advantages of cost and convenience over similar agents such as cefotaxime. We compared the two drugs in a prospective, randomized study of the treatment of chest infections in seriously ill patients. Fifty-one patients (90 percent of whom were mechanically ventilated) received either ceftriaxone, 2g IV once daily, or cefotaxime, 2 g IV thrice daily, for five days. The two groups of patients appeared demographically comparable. Ceftriaxone in a single daily dose of 2 g once daily may not be satisfactory for the treatment of serious chest infections.

Adult↗
PubMed1989

Soft tissue trauma: a randomised controlled trial of the topical application of felbinac, a new NSAID.

Two hundred and thirty-one patients with acute soft tissue injuries were treated in a double-blind placebo-controlled study of felbinac (biphenylacetic acid) gel applied three times daily to the injured site. Those treated with felbinac had significantly greater improvement at Day 4 (p less than 0.001) and Day 7 (p less than 0.02) than those who received placebo. Patients' self-assessment diary cards confirmed superiority of the active treatment as early as Day 2 of the study. Local skin reactions were few (three per cent), mild and recovered spontaneously. Felbinac is an effective management for acute soft tissue injuries and because of its topical application may be safer than oral non-steroidal anti-inflammatory drugs for the treatment of these conditions.

Administration, Topical↗
PubMed1987

Validation of the acuity card procedure for assessment of infants with ocular disorders.

The acuity card procedure has been shown to be a rapid method for the assessment of monocular and binocular grating acuity in normal infants from birth through 36 months of age. The current study seeks to validate the procedure further by using the acuity cards to assess 20 2- to 8-month-old infant patients with ocular disorders, including aphakia, strabismus, ptosis, and orbital hemangioma. Assessments were made with the acuity cards by two different observers, both blind to the infant's diagnosis, and by a third observer using a traditional forced-choice preferential looking (FPL) procedure. One hundred percent of the infant patients completed both binocular and monocular acuity card testing in an average time of 8 minutes per test. Interobserver agreement between acuity card observers and inter-technique agreement were high, and were sustained in individual cases in which the infant's acuity was not predictable from its visible signs. These results help to establish the potential clinical utility of the acuity card procedure for the assessment of infant patients.

Evaluation Studies as Topic↗
PubMed1987

The evaluation of an ultrasound detector (UD) in the measurement of oro-facial dyskinesia.

An ultrasound detector (UD) was compared with a clinical rating (CR) scale in the assessment of oro-facial movements in 23 chronic schizophrenic patients and 23 normal subjects over a period of 4 weeks. The apparatus distinguished well between normal volunteers and dyskinetic patients. There were also highly significant correlations between UD scores and clinical ratings. The results thus confirm both the construct and concurrent validity of the technique. Nevertheless, there was significant variation in the UD scores for some patients between assessments. A technical problem was the inability of some patients to cooperate for more than 30 seconds. The scores of the normal subjects were consistent. With further development and repeated 30-second assessments the technique might be of value in the ascertainment of early dyskinesia in patients at risk and also in measuring drug effects.

Adult↗
PubMed1986

Kunjin virus encephalomyelitis.

Kunjin virus encephalomyelitis is described in a 49-year-old man who presented with an episode of acute encephalitis. He developed profound bulbar, truncal and proximal muscle weakness suggestive of damage to cranial motor nuclei and anterior horn cells. This resolved very slowly. A marked rise in antibody titres to Kunjin virus was shown by haemagglutination inhibition tests. Specific IgM antibodies were detected only against Kunjin virus.

Antibodies, Viral↗
PubMed1986

Monocular acuity in normal infants: the acuity card procedure.

An "acuity card" technique has been developed for rapid assessment of visual acuity in infants. In this procedure an adult observer shows the infant a series of cards that contain gratings of various spatial frequencies and estimates acuity as the highest spatial frequency that the infant is judged to see. The present paper shows that the acuity card procedure can be used in a laboratory setting to estimate both monocular and binocular acuity in infants 1 to 12 months of age. Four monocular and two binocular acuity estimates were obtained on 36 normal infants, six each at ages 4, 8, and 16 weeks and 6, 9, and 12 months. Acuity estimate means and SD's agreed well with previously established preferential looking (PL) norms for each of the test ages. Time required for a monocular or a binocular test averaged 3 to 6 min.

Age Factors↗
PubMed1986

Monocular and binocular acuity estimation in 18- to 36-month-olds: acuity card results.

The acuity card procedure is a useful method for measuring visual acuity in infants 1 to 12 months of age. The results of the present study indicate that the procedure is also a viable method for estimating acuity in children 18 to 36 months of age. Monocular and binocular estimates of acuity were obtained with the acuity card procedure on 36 normal children, 9 each at ages 18, 24, 30, and 36 months. At each of the ages, means and SD's of acuity estimates agreed well with acuity norms from established operant procedures. Mean durations for monocular and binocular estimates averaged 2 to 4 min, and nearly 100% of children were tested successfully both monocularly and binocularly. The flexibility of the required response and the short test times make the acuity cards a promising test of visual acuity in this typically difficult-to-test age range.

Child Development↗