Search PubMed⌕ Search

Biomedical subjects

A Hamilton

Publications and source records attributed to A Hamilton.

At least 109 records · Page 6Linked to original sources
PubMed1985

Maternal-fetal disparity at multiple minor histocompatibility loci affects the weight of the feto-placental unit in mice.

Inbred mice from selected unrelated and congenic strains were mated to determine the relative effects of maternal-fetal disparity at major histocompatibility complex (H-2) and non-H-2 minor histocompatibility antigens on the feto-placental unit at 14 days of gestation. A significant increase in weight of the feto-placental unit was observed only when mother and fetus differed at multiple minor histocompatibility loci. No increase in the weight of the feto-placental unit was observed when mother and fetus differed only at H-2. These results suggest that immunostimulation of the fetus results from a maternal response to minor histocompatibility antigens and not to H-2 antigens.

Animals↗
PubMed1985

Causal links between plasma and CSF endorphin levels in stress: vector-ARMA analysis.

To explore causal links between vital sign responses and immunoreactive beta-endorphin ("i-BE") rises in blood and CSF during ovine endotoxin stress, we analyzed concurrent i-BE levels in these two compartments by a "vector-ARMA" (= autoregressive moving average) method. This technique--widely used for modeling in other applications--has not to our knowledge been employed to study dynamic relationships of neuropeptides. Log-transformed i-BE levels were first "filtered" by repeated observations ANOVA to confirm significance of rises in both compartments. Next, vector-ARMA methodology was applied to derive an optimal causal model of vital sign changes and i-BE entry into plasma vs. CSF pools. The model indicated that reflux of i-BE from blood into CSF contributed to increases in CSF levels of this hormone. This novel application to neuroendocrinology of this approach illustrates its utility in evaluating changes in one or more neuropeptide levels in multiple compartments to indicate potentially causal relationships.

Animals↗
PubMed1984

A cross-validation of Paulson's discriminant function-derived scales for identifying "at risk" child-abusive parents.

Paulson, Afifi, Chaleff, Liu, & Thomason (1975) developed a series of special subscales from the MMPI for identifying individuals who are at risk for child-abusive behavior. The initial results were highly encouraging, with the scales correctly identifying 93 to 100% of the subjects in their sample. Unfortunately, Paulson et al. (1975) failed to cross-validate their findings before publication. When the six scales were cross-validated on an independent sample from the population of child-abusing parents, significant shrinkage in the accuracy of prediction was found. The use of the special subscales for identifying "at risk" parents in prenatal clinics, pediatric clinics, pediatric clinics and mental health centers as originally suggested by Paulson and his colleagues is seriously questioned.

Adult↗
PubMed1982

Endotoxin-stimulated opioid peptide secretion: two secretory pools and feedback control in vivo.

Small doses of endotoxin evoked a dramatic biphasic response of opioid peptide secretion into blood in sheep. The first phase began within minutes and coincided with a brief hypertensive response to endotoxin well before the appearance of fever or hypotension. The ratio of beta-endorphin to beta-lipotropin fell abruptly at the onset of the second phase of release, suggesting early depletion of a pool rich in beta-endorphin and subsequent emergence of a pool rich in unprocessed precursor. The concentration of cerebrospinal fluid opioids increased tenfold during the second phase. Naloxone administration augmented endotoxin-induced opioid secretion in both early and late phases, suggesting a short-loop feedback regulation of stress-induced endorphin secretion.

Animals↗
PubMed1981

Sexual problems in arthritis and allied conditions.

There is need for a greater readiness among the medical and paramedical professions to recognize the widespread occurrence of sexual problems in patients with arthritis and allied conditions. Sexual image, sexual drive, sexual competence, sexual expression, and sexual opportunity may all be adversely affected by the onset of arthritis, the type and degree of effect depending on the nature, severity, and duration of the disease and on the social and marital state of the patient. Single patients may have difficulty in forming stable sexual relationships and married patients in creating a mutually satisfying pattern of sexual expression. The physical and psychological state of patient and partner and the medication of both need careful consideration to determine contributory causes to the individual problem-complex of each patient. Based on the experience of 12 years' sexual counselling at a disabled living unit and an orthopaedic hospital, and of 4 years at a weekly clinic for disable people with sexual problems, the causes and means of amelioration of these problems are discussed.

Arthritis↗
PubMed1980

Adrenocorticotropic hormone may be transported directly from the pituitary to the brain.

Experiments were designed to test the hypothesis that pituitary hormones may be delivered directly to the brain. Concentrations of adrenocorticotropic hormone (ACTH) in the plasma were determined in blood samles obtained simultaneously from the carotid artery, the sagittal sinus, and the jugular vein of three awake sheep. Seizures were induced electrically to stimulate ACTH secretion, and at precise intervals thereafter several simultaneous comparisons were made in each animal. In many of the post-seizure comparisons, the ACTH plasma concentrations within the sagital sinus exceeded those within the carotid artery as well as those within the jugular vein, indicating that this hormone was released from the pituitary and carried directly through capillary beds of brain to the venous blood within the sagittal sinus. The experiment was repeated in one hypophysectomized sheep and, in this animal, ACTH concentration in the plasma was reduced, but that in the sagittal sinus still was elevated after the seizure, an indication that some ACTH (or ACTH-like material) was released from the brain itself.

Adrenocorticotropic Hormone↗
PubMed1979

Upper limb amputees.

Explore the source record for details and available documents.

Activities of Daily Living↗
PubMed1978

Isolation of 57Co-cobalamin coenzymes at high specific activity from Streptomyces griseus.

The distribution of radio-labelled cobalamins in Streptomyces griseus grown in medium containing 57Co-cobalt chloride has been estimated by two-dimensional thin-layer chromatography and bioautography. 57Co-Methylocobalamin (Me[57Co]Cbl) was the major form in the mycelium together with smaller amounts of 57Co-adenosylcobalamin (Ado[57Co]Cbl) and 57Co-hydroxocobalamin (OH[57Co]Cbl). The OH[57Co]Cbl was detected in three forms having, respectively, anionic, cationic and neutral properties. A simple technique has been developed to isolate and purify Me[57Co]Cbl and Ado[57Co]Cbl from the mycelium using column chromatography on ion-exchange celluloses. Small quantities of each cobalamin coenzyme have been obtained at 90--96% purity and specific activities of 190--230 muCi/microgram.

Chromatography, DEAE-Cellulose↗