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Biomedical subjects

D M Lawrence

Publications and source records attributed to D M Lawrence.

At least 55 records · Page 3Linked to original sources
PubMed1992

Kappa opioid binding sites on the R1.1 murine lymphoma cell line: sensitivity to cations and guanine nucleotides.

The present study describes the characterization of an opioid binding site on membranes prepared from the R1.1 cell line, a murine thymoma. Specific (-)[3H]bremazocine binding was saturable, stereoselective, and limited to a single high affinity binding site with a Kd value of 15.2 +/- 1.6 pM and a Bmax value of 54.8 +/- 6.0 fmol/mg of protein. The kappa-selective alkaloids and dynorphin peptides inhibited (-)[3H]bremazocine binding with Ki values of less than 1 nM, in contrast to mu- and delta-selective ligands. The high affinity of this site for alpha-neo-endorphin and U50,488 suggests that this kappa opioid binding site resembles the kappa 1b subtype. NaCl, as well as other mono- and divalent cations, inhibited (-)[3H]bremazocine binding. In the presence of NaCl, the nucleotides GTP, GDP, and the nonhydrolyzable analog guanylyl-5'-imidodiphosphate (Gpp(NH)p) also decreased (-)[3H]bremazocine binding, suggesting that this kappa opioid binding site is coupled to a G-protein. In summary, R1.1 cells possess a single high affinity kappa opioid receptor that shares many properties with brain kappa 1b opioid receptors.

Animals↗
PubMed1991

A provider's view of prevention approaches in a prepaid group practice.

Kaiser Permanente's health care delivery system and its efforts to integrate public health preventive medicine and curative medicine are described. The author advocates an increased focus on prepaid delivery systems like Kaiser Permanente as the best vehicle to achieve the full promise of health screening, health education, and life-style modification. Because these systems have brought the proper incentives into alignment, prevention and health promotion have become effective tools to achieve cost containment goals. A number of Kaiser Permanente projects are highlighted that demonstrate integration of public health preventive medicine and curative medicine: the Northern California Region's uniform health appraisal examination, which is linked with health education and counseling; the Colorado Region's breast cancer screening program, which is expected to show a higher rate of early breast cancer detection than in the general population; cooperative efforts with two Northern California towns to reduce smoking through a community-wide project; educational theatre programs aimed at early intervention and education of children before high-risk behaviors have become established life-style; and research projects that are possible because of an integrated program. Also, several forces that could endanger integrated systems including cost control practices of employers and insurers, and public policy such as mandating specific benefits, are noted.

Breast Neoplasms↗
PubMed1987

Amniotic fluid testosterone and testosterone glucuronide levels in the determination of foetal sex.

Unconjugated testosterone levels were assayed in 351 amniotic fluid samples obtained at 15-19 weeks gestation. The median values for unconjugated testosterone in the 166 female foetuses and 185 male foetuses were 137 and 712 pmol/l respectively. Sixteen amniotic fluid samples from male foetuses had unconjugated testosterone levels lower than the highest female unconjugated testosterone value (361 pmol/l). Testosterone glucuronide was measured in amniotic fluid from 48 female and 55 male foetuses. There was a significant sex difference in the median values of testosterone glucuronide between female (median 160 pmol/l, range 64-465 pmol/l) and male (median 817 pmol/l, range 68-3707 pmol/l) amniotic fluid specimens (P less than 0.001). Of the sixteen male foetuses with amniotic fluid unconjugated testosterone levels in the female range, 12 had amniotic fluid testosterone glucuronide levels within the male testosterone glucuronide range of values. Hence used in conjunction with unconjugated testosterone, testosterone glucuronide increased the predictive accuracy of foetal sexing from 95.4 to 98.9%. Testosterone sulphate was measured in 24 female and 25 male amniotic fluid samples. There was no Testosterone sulphate was measured in 24 female and 25 male amniotic fluid samples. There was no significant difference between female (median 2591 pmol/l) and male (median 2964 pmol/l) testosterone sulphate levels.

Amniocentesis↗
PubMed1984

Hormone levels in the reproductive system of normospermic men and patients with oligospermia and varicocele.

The endocrine milieu on which spermatogenesis and sperm maturation mainly depend was evaluated quantitatively with simultaneous measurements of FSH, LH, PRL, testosterone, estrone, estradiol (E2), and sex hormone-binding globulin concentrations in spermatic venous plasma, antecubital plasma, seminal fluid, and wash fluid from vas deferens in 16 normospermic men and 24 oligospermic patients. Anesthesia and surgical stress caused a rise of only PRL and E2 (P less than 0.001-0.01). Mean FSH, LH, and PRL levels were comparable in antecubital and spermatic venous plasma, and antecubital values were higher in oligospermic patients for FSH and LH (P less than 0.05-0.001). Mean (+/- SD) T levels were similar for normospermic and oligospermic men in spermatic venous plasma (473 +/- 75 and 439 +/- 270 ng/ml), in antecubital plasma (6.5 +/- 1.3 and 6.6 +/- 1.8), and in seminal fluid (0.3 +/- 0.1 for both). Minute quantities of testosterone were detected in pooled wash fluid (0.08 ng). For E2, similar concentration gradients from high to low levels were found in normospermic and oligospermic men (spermatic venous plasma = 926 +/- 205 pg/ml and 1090 +/- 262; antecubital plasma = 31.0 +/- 12.0 and 28.4 +/- 1.9; seminal fluid = 14.3 +/- 2.3 and 12.0 + 2.8). Estrone was also high in spermatic venous and low in antecubital plasma but higher in seminal fluid than in antecubital plasma. Sex hormone-binding globulin levels were slightly though not significantly lower in spermatic venous (23 +/- 10 nmol/liter) than in antecubital plasma (28 +/- 6), but not measurable in seminal fluid. These results define important aspects of the endocrine milieu prevailing in the male reproductive tract and demonstrate a change of the relative activity of androgens and estrogens from the testis to the seminal fluid.

Adult↗
PubMed1983

Cutaneous lesions in hairy-cell leukemia. Case report and review of the literature.

A patient is described in whom cutaneous lesions were the initial manifestation of hairy-cell leukemia. Touch preparations made immediately on removal of a 3-mm punch biopsy specimen of the cutaneous lesions revealed acid-phosphatase positive, tartrate-resistant staining in the leukemic cells, and helped to establish the diagnosis. Specific eruptions occur in approximately 7% of patients with hairy-cell leukemia, appearing grossly as disseminated, erythematous maculopapules, with a perivascular mononuclear leukemic cell infiltrate seen microscopically. A review of the English literature indicates that cutaneous manifestations are not generally recognized as a diagnostic source in individuals with hairy-cell leukemia, and biopsy is seldom undertaken.

Acid Phosphatase↗
PubMed1982

Plasma noradrenaline and adrenaline levels in normal pregnancy and in pregnancy-induced hypertension.

Plasma concentrations of noradrenaline and adrenaline were measured serially during normal pregnancy in 52 women who remained normotensive and in nine who developed pregnancy-induced hypertension but were otherwise normal. There was a significant fall in both noradrenaline (P less than 0.005) and adrenaline (P less than 0.05) levels during normal pregnancy. Throughout pregnancy the mean levels of both catecholamines were lower in the patients who developed pregnancy-induced hypertension than in the normotensive patients. There was no evidence of increased sympathetic nervous system activity in the women who developed pregnancy-induced hypertension.

Adult↗
PubMed1981

Reduced sex hormone binding globulin and derived free testosterone levels in women with severe acne.

Reduced circulating sex hormone binding globulin (SHBG) levels were found in 54% of a group of women with moderate to severe acne and in 60% of another group of twenty-three women who had acne complicated by hirsutism and/or irregular menstrual cycles. The concentrations of SHBG for the women with acne alone (mean 48 +/- 24 nmol/l) and for those with acne and hirsutes (mean 39 +/- 18 nmol/l) were compared with the SHBG concentrations of fifteen unaffected women with normal menstrual cycles (mean 70 +/- 19 nmol/l). The differences in mean SHBG values for both groups of women with acne were significant (P less than 0.001) on comparison with the mean for the unaffected women. Twenty-nine per cent of the women with acne had elevated testosterone values (mean testosterone concentration for the group 1.5 +/- 0.3 nmol/l) and 41% had elevated 'derived' free testosterone levels (mean 21 +/- 6 pmol/l). Of the women with acne and hirsutes 65% had elevated plasma testosterone levels (mean 2.1 +/- 0.6 nmol/l) and 89% had elevated free testosterone concentrations (mean 31 +/- 10 pmol/l). The mean values for testosterone and free testosterone in the plasma of unaffected women (mean testosterone concentration 1.1 +/- 0.3 nmol/l and free testosterone 13 +/- 4 pmol/l) were significantly lower than in women with acne alone (P less than 0.01 and P less than 0.001) and in women with acne and hirsutism (P less than 0.001). This study indicates that a deficiency in SHBG and an elevation in 'derived' free testosterone is a frequent finding in women with severe acne and may be a significant factor in the aetiology and/or perpetuation of this condition.

Acne Vulgaris↗
PubMed1980

Associating Embedded Figures Test Performance with extreme hysteria and psychasthenia MMPI scores in a psychiatric population.

21 female subjects from a psychiatric population scoring high on one of two MMPI scales, Hysteria or Psychasthenia, were given Jackson's (1956) shortened version of the Embedded Figures Test. Hysteria correlates positively and significantly .71 with time spent in detecting embedded geometric figures. Obsessive-compulsiveness and Embedded Figures Test performance time are negatively correlated -.63. The average times were 102.5 sec. for hysteria subjects and 62.6 sec. for psychasthenia subjects. Chi-squared establishes the significant association of MMPI measurements for hysteria and obsessive-compulsiveness with field-dependence and field-independence, respectively.

Adult↗
PubMed1979

Role of verbal representations in testing recognition of naturalistic sounds.

This paper reports two experiments concerned with verbal representation in the test stage of recognition memory for naturalistic sounds. In Study I 10 subjects produced verbal description to 50 sounds and after a 7-day delay 5 subjects reviewed self-produced verbal descriptions while 5 did not prior to testing for recognition. Review of descriptions increased recognition to 94.4% compared to 88.5% for those with no review. In Study II 16 subjects produced verbal descripitions to 50 naturalistic sounds. After a 7-day delay all subjects reviewed descriptionss of one-half of the items which were "targets" and 8 subjects reviewed description of 25 "non-targeted" items. The latter condition produced interference, observed as a significant decrement in recognition from 90.3% to 86.5%.

Auditory Perception↗
PubMed1979

Comparison of accuracy in auditory and tactile recognition memory for environmental stimuli.

Accuracy rates for auditory and tactile recognition of naturalistic stimuli over a 7-day period are compared. 40 subjects listened to 50, 107, or 194 naturalistic sounds and were tested immediately or after delays of 2 or 7 days. 30 other subjects handled but did not visually inspect 150 common objects and were tested over the same three delay intervals. Recognition accuracy for sounds was 87.5%, 82.5%, and 80.4% while common objects were recognized at 96.0%, 93.8%, and 88.5% rates of accuracy. Tactile recognition memory was superior to auditory recognition memory. The recognition accuracies of both modalities were affected by the delay interval. The number of items inspected had no effect on the recognition memory for sounds. Following a delay of 1 wk., the accuracy of recognition relative to the original level of function was 92% for both modalities.

Auditory Perception↗
PubMed1979

Report on blind subjects' tactile and auditory recognition for environmental stimuli.

In two related experiments on recognition-on touch and audition-accuracy rates were obtained from congenitally blind subjects and compared with those for normally sighted subjects. In Exp. 1, 5 blind subjects inspected, i.e., handled, 150 common objects and were tested after a delay of 7 days. In Exp. 2, 9 blind subjects listened to 194 naturalistic sounds and were also tested after a 7-day delay. Accuracy of tactile recognition for the blind was 89.4% while it was 87.9% for the normally sighted. Sound recognition by blind subjects was 76.6% and for the normally sighted it was 78.4%. Neither difference was statistically significant.

Adult↗
PubMed1979

Testosterone concentration in different functional compartments of the male reproductive tract.

The concentration of testosterone in testicular tissue (TT), spermatic vein blood (SVB), cubital blood (CB), and seminal fluid (SF) was estimated using a radioimmunoassay technique in a total of 50 normospermic, oligozoospermic, and azoospermic men. Testosterone was also determined in cauda epididymis-vas deferens ductus wash fluid (WF) in 6 normospermic men. In 2 oligozoospermic men the testosterone concentration in TT was 556 and 725 ng/g tissue, respectively. In 9 normospermic men the mean SVB testosterone concentration was 473 ng/ml. CB and SF concentrations of this steroid were 6.8 and 0.4 ng/ml in normospermic, 6.4 and 0.5 ng/ml in oligozoospermic, and 4.9 and 0.4 ng/ml in azoospermic men, respectively; the difference among the three groups was not significant. The SVB:CB and SVB:SF ratios in normospermic men were 71 and 1549, respectively, while the CB:SF ratio was 18 in normospermic, 18 in oligozoospermic, and 16.6 in azoospermic men. Testosterone could not be detected in individual specimens of WF, but after pooling of samples a concentration of 0.08 ng/ml WF was estimated. These results demonstrate the relative concentrations of testosterone in the different functional compartments of the reproductive tract in man and facilitate a better understanding of its function.

Adult↗
PubMed1978

Pituitary-testicular interrelationships in mumps orchitis and other viral infections.

Leydig-cell function was assessed in 27 men with acute mumps orchitis by measuring plasma testosterone concentrations before and after the administration of human chorionic gonadotrophin (HCG). The test was also performed on groups of patients with other febrile viral infections and mumps without orchitis and on healthy euspermic men. The concentrations both before and after HCG were significantly lower in patients in the acute phase of mumps-but not in those with other viral infections and mumps without orchitis-than in the healthy men. Basal concentrations of follicle-stimulating hormone (FSH) and luteinising hormone (LH) were significantly increased in patients with acute mumps orchitis, while an exaggerated response to LH-releasing hormone was noted in four patients after the acute phase of the disease. Raised plasma LH concentrations were also found in several patients with viral infections, including mumps without orchitis. There appeared to be no particular merit of any of the treatments used (aspirin, prednisolone, and cold baths). In patients reevaluated three to five and 10 to 12 months after the acute phase of their disease the basal testosterone concentrations were similar to those of the healthy men, but several of the patients showed a severely impaired response to HCG. Mean basal FSH and LH concentrations were significantly increased 10 to 12 months after the acute phase, while the mean LH concentration was also raised at three to five months.It is concluded that mumps orchitis impairs Leydigcell function during the acute phase of the disease but may also have a more permanent damaging effect, similar to that found in the germinal epithelium.

Acute Disease↗
PubMed1978

Prolactin and luteal insufficiency.

The relationship between mid-luteal plasma levels of progesterone and prolactin was studied in 75 women with regular menstrual cycles. Eighteen women had normal prolactin (mean 260 +/- 51.7 mU/l) and normal progesterone levels (mean 67 +/- 21.3 nmol/l). Thirty-nine women had elevated prolactin levels (mean 850 +/- 503 mU/l): progesterone levels were normal in all cases (mean 61 +/- 22.3 nmol/l). Eighteen women had evidence of luteal deficiency (mean progesterone 15.3 +/- 7.7 nmol/l); prolactin levels were normal in all cases (mean 243 +/- 106 mU/l). There was no correlation between plasma prolactin and progesterone levels.

Adult↗
PubMed1978

The treatment of mild adrenal hyperplasia and associated infertility with prednisone.

Thirty patients with mild post-pubertal adrenal hyperplasia, characterized by raised urinary 17-oxosteroid levels and variable combinations of irregular menses, hirsuties, infertility, and spontaneous abortion, were treated with 2.5 to 10 mg of prednisone per day and all conceived (55 pregnancies). With this treatment, regular, ovulatory cycles occurred immediately in 25 patients, and after two to six months, in the rest. Treatment reduced raised 17-oxosteroid levels to normal and brought about some improvement in hirsuties and acne. Forty-seven pregnancies ended in the birth of liveborn infants; one of these died of prematurity and another had congenital emphysema. One pregnancy was terminated, two were of unknown outcome and five (9.4%) ended in abortion. Before treatment, 20 out of 22 pregnancies (91%) had ended in abortion.

17-Ketosteroids↗