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Biomedical subjects

R H Martin

Publications and source records attributed to R H Martin.

At least 145 records · Page 8Linked to original sources
PubMed1982

Imaging of human melanoma xenografts in nude mice with a radiolabeled monoclonal antibody.

External photoscanning with display of radioactivity data as a color-scaled image detected xenografts of human melanoma in male nude inbred mice of BALB/c background 48 hours after injection of 131I-labeled monoclonal IgG 225.28S that is specific for human melanoma. A 131I-labeled polyclonal goat IgG against human melanoma-associated antigens could also image the tumor, but with this preparation there was considerable localization of radioactivity in normal tissues, resulting in less satisfactory tumor definition. Labeled normal mouse IgG did not image the melanoma grafts. Assay of radioactivity in tissues of melanoma-grafted mice confirmed tumor-specific localization of the antimelanoma antibodies. The tumor:blood ratio of radioactivity was 6.55 with the monoclonal antimelanoma IgG and 0.45 with the polyclonal IgG.

Animals↗
PubMed1982

Direct chromosomal analysis of human spermatozoa: preliminary results from 18 normal men.

Chromosomal analysis of 240 spermatozoa from 18 normal men was performed using in vitro fertilization of zona-free golden hamster eggs. The frequency of chromosome abnormalities in this population was 9.2% (22/240). Of the abnormal complements, 18 were aneuploid (13 hyperploid and five hypoploid) and four had a chromosome break. The sex ratio of Y-bearing to X-bearing sperm was .68. The frequency and type of sperm chromosome abnormalities is compared with those seen in spontaneous abortions.

Abortion, Spontaneous↗
PubMed1981

Suppression by bromocriptine of the serum lactalbumin peak associated with human lactogenesis.

The endocrine environment necessary for human lactation has not yet been clearly defined. In particular the role of prolactin is uncertain, since levels of this hormone usually fall to the normal non-lactating range during the course of prolonged lactation. We have found that the immediate post-partum peak of serum lactalbumin associated with lactogenesis was abolished by treatment with bromocriptine. This suggests a direct relationship between prolactin and lactalbumin production at this time.

Bromocriptine↗
PubMed1981

Oestrogen stimulated neurophysin in pregnancy and lactation.

Serum concentrations of oestrogen stimulated neurophysin (ESN) were measured throughout pregnancy in thirty-one women and until 6 weeks post-partum in a further twenty-three. During pregnancy ESN rose progressively and values during labour were similar to those immediately before delivery. There were significant correlations (P less than 0.05) between serum ESN and oestradiol values measured in samples from four patients. After delivery the concentration of ESN fell rapidly to the range for non-pregnant women by 5 days post-partum, whether the mothers lactated or not, and remained fairly constant for the next 6 weeks. Bromocriptine or metoclopramide, drugs which affect prolactin secretion, were without effect on ESN values. At 8 days post-partum in sixteen of the eighteen patients studied there was an increase in ESN concentration 30 min after suckling commenced. At 6 weeks similar changes occurred in five of the ten subjects studied. In contrast, at 8 days there was no significant change in ESN in four mothers who bottle fed their babies over the 90 min studied. The relationship between ESN and hormonal changes during pregnancy and lactation is discussed in the light of these results.

Estradiol↗
PubMed1981

Observer variation in the angiocardiographic diagnosis of mitral valve prolapse.

The purpose of this study was to assess the reliability of the angiocardiographic diagnosis of mitral valve prolapse by measuring agreement between observers using defined diagnostic criteria. Sixty high-quality left ventriculograms, selected to include many that showed possible mitral valve prolapse, were reviewed by three angiocardiographers. Disagreement between observers as to positivity occurred in 26 percent and 30 percent of the cases on two reviews, and disagreement as to specific scallop involvement occurred in 68 percent and 78 percent of the cases. A specific observer agreed with himself in interpretation of positive 78 to 82 percent of the time and in the interpretation of specific scallop involvement 55 to 90 percent of the time. These results indicate that in the absence of generally agreed upon quantitative angiocardiographic criteria for the diagnosis of mitral valve prolapse, there is considerable variability among observers in the interpretation of mitral valve prolapse by angiocardiographic studies.

Angiocardiography↗
PubMed1980

X-linked mental retardation with macro-orchidism and marker-X chromosomes.

The family of 2 men with X-linked mental retardation was investigated for the presence of the marker-X chromosome and macro-orchidism. Lymphocyte cultures were set up in media F-10 and 199. Chromosomes were G-band-stained and slides coded for blind analysis. Marker-X chromosomes and autosomal gaps were seen only in cultures prepared with medium 199. Autosomal gaps were seen in all family members and controls. The marker-X chromosome was present inaffected male (3% and 15.5%) and female family members (0.5%-6.5%) but not in controls or a normal male family member. Bilateral macro-orchidism was present in 1 affected male and unilateral macro-orchidism in the other. Both had normal penile measurement. The replication pattern of the marker-X chromosome was studied in 1 woman by BrdU labelling. BrdU decreases the frequency of marker-X expression. As the marker-X chromosome was the late-replicating X in 9/20 cells, it appears that there is no preferential inactivation of the marker-X in this woman.

Chromosomes, Human↗
PubMed1980

Incidence of low back pain and pre-placement x-ray screening.

The primary purpose of pre-placement back x-ray screening is to reduce the incidence of low back problems. This study was designed to address the specific question of whether or not this objective is achieved, without directly looking at the predictive value of radiological abnormalities of the lumbar spine. Two retrospective cohorts of steelworkers were identified: one group hired before, and one after, introduction of back x-rays into an otherwise identical pre-placement medical examination. The two cohorts were stratified by age and work activity, and by use of a modified life table method were followed for 12 years. All health incidents, modified work, lost time, or permanent job changes were noted. Analysis revealed no statistically significant differences between cohorts for the parameters studied. The inclusion of low back x-ray screening into a comprehensive pre-placement medical examination had no significant effect on the subsequent incidence of low back pain in the cohort of steelworkers studied.

Adult↗
PubMed1980

Human alpha-lactalbumin and hormonal factors in pregnancy and lactation.

Serum alpha-lactalbumin was monitored throughout pregnancy in twelve women and in a separate group of nineteen women during the first 3 months postpartum. During pregnancy alpha-lactalbumin rose significantly until the mid trimester (P less than 0.001). From then until term, concentrations remained stable. Concentrations during labour were significantly higher (P less than 0.01) than those seen at term. alpha-lactalbumin, 17 beta-oestradiol and progesterone concentrations behaved similarly during the first week of the puerperium in both lactating (n = 10) and non-lactating (n = 9) subjects. A large surge of alpha-lactalbumin closely followed the clearance of high circulating concentrations of sex steroids in both groups. Prolactin concentrations were significantly greater (P less than 0.02) in lactating subjects by the third postpartum day. By the third postpartum week alpha-lactalbumin concentrations in lactating subjects had stabilized at labour levels in a milieu of high prolactin levels and depressed production on 17 beta-oestradiol and progesterone. Conversely, in non-lactating subjects alpha-lactalbumin concentrations fell, as did prolactin, coincidental with a rise in 17 beta-oestradiol, progesterone concentrations remaining barely detectable. The apparent control mechanisms for human alpha-lactalbumin secretion and thus, lactation, are discussed in the light of the data presented.

Estradiol↗
PubMed1980

Screening for fetal risk with urinary oestrogen: creatinine ratio at 34 weeks.

The urinary oestrogen:creatinine (O/C) ratio was measured in first morning specimens of 261 women at 34 weeks gestation to assess prospectively its potential in predicting fetal complications. Forty-two patients (16.1 per cent) had low O/C ratios. All three stillbirths in the series occurred in this group and the incidences of fetal growth retardation and fetal distress in labour were also significantly increased. These complications were unusual when the O/C ratio was high. The O/C ratio at 34 weeks reflected fetal well-being more accurately than clinical examination or blood pressure measurement. The mean O/C ratios of cigarette smokers non-smokers were similar, although smokers were delivered of lighter babies. Measurement of the urinary O/C ratio is simple and inexpensive. Used as a screening test at 34 weeks it appears to provide an early and fairly reliable indication of reduced placental function.

Creatinine↗
PubMed1979

Doughnut pattern of technetium-99m pyrophosphate myocardial uptake in patients with acute myocardial infarction: a sign of poor long-term prognosis.

Thirty survivors of acute myocardial infarction with 3+ or 4+ positive technetium-99m pyrophosphate myocardial scintigrams were followed up for 28 +/- 3.1 months (mean +/- standard deviation). Three patient groups were identified from the pattern of radioactive uptake in the scintigram: Group I, 16 patients with focal uptake (anterior in 7, lateral in 2, posterior in 3 and inferior in 4); Group II, 6 patients with anterior myocardial infarction and a doughnut pattern of uptake; Group III, 8 patients with nontransmural myocardial infarction and a diffuse pattern of uptake. Late complications developed in all patients with the doughnut pattern of uptake compared with 43 percent of patients with the focal pattern and 12 percent of patients with the diffuse pattern. After discharge from the hospital, five of six patients with a doughnut pattern of uptake died (mean survival time 9.8 months after the initial myocardial infarction). This mortality rate (83 percent) was significantly greater than that of patients with a focal (mortality rate 6 percent) or diffuse (no mortality) pattern of uptake. The doughnut pattern of technetium-99m pyrophosphate myocardial uptake in patients with acute myocardial infarction appears to identify a subgroup of patients with a very poor long-term prognosis.

Angina Pectoris↗