Search PubMed⌕ Search

Biomedical subjects

M G Miller

Publications and source records attributed to M G Miller.

At least 73 records · Page 4Linked to original sources

Use of Tetraethylthiuram Disulfide to Discriminate between Alternative Respiration and Lipoxygenase.

Mitochondria from axes of Glycine max (L.) Merr. cv. Chippewa 64 seedlings purified on discontinuous Percoll gradients exhibited classical cyanide-resistant respiration. These mitochondria also possessed lipoxygenase activity, as determined by O(2) uptake in the presence of 0.8 millimolar linoleic acid. This activity is inhibited by most known inhibitors of alternative respiration (i.e. hydroxamates and propyl gallate). Tetraethylthiuram disulfide (disulfiram) at 50 micromolar inhibited cyanide-resistant succinate oxidation by 90 per cent, whereas concentrations as high as 100 micromolar had no effect on lipoxygenase activity. Use of tetraethylthiuram disulfide allows discrimination between alternative respiration and lipoxygenase activity in mitochondria.

Journal Article↗

Integration of hospital care for the mentally ill: a status report.

Analysis of DHSS statistics from the Mental Health Enquiry for 1975 indicates that, contrary to some predictions, district general hospital psychiatric units (DGHU) are assuming a proportionate share of the burden of hospital care for most groups of mentally ill individuals. Comparisons of admissions to mental illness hospitals and DGHUs indicate no major differences in most categories of patient characteristics (age, sex, order of admission and diagnosis); where differences do exist, they appear to be decreasing. Concern that DGHUs might 'cream off' patients with less serious illnesses, with a resultant 'two-tier' system of mental hospital care, would thus appear to be unwarranted.

Adult↗

The changing urban-suburban distribution of medical practice in large American metropolitan areas.

The twenty largest multi-county SMSAs in the U. S. were studied for trends in the suburbanization of medical practice from 1959 to 1974. Fifteen of them allowed a distinction between suburbs and central city on the county level according to criteria developed from a New York City pilot study. In all SMSAs, the density of hospital-based physicians was higher in central cities than in suburbs and still increasing more rapidly there, though hospital practice is also starting to grow in the suburbs at an appreciable rate. The same trends were found for physicians in non-patient care activities. Office based specialists in large Northeastern SMSAs increased much more rapidly in the urbanized suburbs than in the central cities. In the Southern and Western SMSAs, on the contrary, office-based specialists continued to increase rapidly in the central cities despite concentrations already far greater than in the Northeast. Suburban desities were growing more slowly in these areas. General practitioners declined uniformly everywhere, apparently simply by attrition. Implications of these trends for health care are discussed.

Family Practice↗

Low Temperature Effects on Soybean (Glycine max [L.] Merr. cv. Wells) Free Amino Acid Pools during Germination.

The free amino acid concentrations in cotyledons and axes of soybean (Glycine max [L.] Merr. cv. Wells) seedlings were determined by automated single column analysis after germination at 10 and 23 C. After 5 days germination at 10 C, glutamate and aspartate were in high concentration in both cotyledons and axes (38 and 24% of total free amino acids recovered, respectively), whereas the concentrations of their amide derivatives, asparagine and glutamine, were low in cotyledons (4.4%) and high in axes (21%). In contrast, after 5 days germination at 23 C, asparagine and glutamine accounted for 22 and 45% of total free amino acids in cotyledons and axes respectively, and aspartate and glutamate concentrations were low. The activities of glutamine synthetase and asparagine synthetase were considerably lower in tissues from the 10 C treatment than those from the 23 C treatment.Aspartate and glutamate concentrations were nearly equal in all but one sample. Both glutamate oxaloacetate transaminase and glutamate dehydrogenase activities were much higher in axis tissues at 23 C as compared to 10 C. Arrhenius plots of axis glutamate oxaloacetate transaminase and glutamate dehydrogenase activities were biphasic and triphasic, respectively, with energies of activation for both increasing with low temperature. Energies of activation were identical for glutamate oxaloacetate transaminase from 10 and 23 C treatments but much higher for glutamate dehydrogenase from 23 C-treated axes. This indicates a difference in enzyme complement for glutamate dehydrogenase with the two treatments.Hydrolysis of free amino acid sample (basic fraction) aliquots showed large quantities of peptides in 23 C-treated axes at 2 days, while few or no peptides were found in the 10 C treatment. Amino acid residues most prevalent in peptides were aspartate, threonine, serine, glutamate, and glycine.

Journal Article↗

The mind-body dichotomy reified: an illustrative case.

Cartesian dualism, the splitting of human existence into mind versus body, is at times reified with unfortunate consequences. The authors report a case in which a social policy formulation based on such diagnostic dualism resulted in the denial of health-related facility placement to a patient. They argue that this denial was prejudicial and illogical and that benefits should be related to a functional disability rather than to diagnosis.

Adolescent↗

The aftercare clinic as a residency training site. 'Community neuropsychiatry'.

Refocusing service and research priorities in psychiatry toward problems of major mental illness and its long-term management requires that more specific attention be paid to this area by residency training programs. A "community neuropsychiatry" residency training experience based in a state hospital aftercare clinic is described as one model for achieving this objective. Supplemented by didactic course work in mental health administration, the history and theory of community psychiatry, and experiences in other, varied service settings, this program has proved to be valuable for learning and teaching skills basic to community psychiatry practice.

Adult↗

Low Temperature Effects on Soybean (Glycine max [L.] Merr. cv. Wells) Mitochondrial Respiration and Several Dehydrogenases during Imbibition and Germination.

The influence of low temperature on soybean (Glycine max [L.] Merr. cv. Wells) energy transduction via mitochondrial respiration and dehydrogenases was investigated in this study during imbibition and germination. Mitochondria were isolated from embryonic axes of seeds treated at 10 and 23 C (control) by submergence in H(2)O for 6 hours and maintenance for an additional 42 hours in a moist environment. Arrhenius plots of initial respiration rates revealed that those from cold-treated axes had respiratory control (RC) ratios of near 1.0 above an inflection in the plot at 8 C. Arrhenius plots of control axes mitochondrial respiration showed RC ratios of 2.8 above and 5.0 below an inflection temperature of 12.5 C. Energies of activation for mitochondrial respiration between 20 and 30 C for the cold and control treatments were 7.8 and 15.6 kcal/mole, respectively. These data indicate possible differences in mitochondrial membranes, degree of mitochondrial integrity, and mitochondrial enzyme complement between the two treatments.Glutamate dehydrogenase (GDH), malate dehydrogenase (MDH), alcohol dehydrogenase (ADH), glucose-6-phosphate dehydrogenase (G6P-DH), and NADP-isocitrate dehydrogenase (NADP-ICDH) were assayed from whole seeds and axes (after germination) during the 48 hours of temperature treatments. Activity of these dehydrogenases decreased during the first 6 hours with the exception of MDH. After germination at 23 C (48 hours) all five dehydrogenases increased in activity. Arrhenius plots of cotyledon dehydrogenase activities indicated that one inflection temperature between 6 and 18 C was present for each enzyme assayed. Differences were seen in Arrhenius plots of axes dehydrogenase activities with the two temperature treatments in the cases of GDH and MDH from mitochondrial pellets and with differences in enzyme extraction media. These data suggest that the temperature treatments yield differences in mitochondrial enzyme complement. There were no detectable inflection temperatures for the activities of G6P-DH and ADH extracted from axes. Arrhenius plots of NADP-ICDH activity indicated extreme cold sensitivity. The slopes of the plots for axes NADP-ICDH were very similar to those for mitochondrial respiration (23 C treatment) suggesting that this enzyme may limit mitochondrial respiration at low temperature in soybean tissues grown at moderate temperatures.

Journal Article↗

Debeaking method for Bobwhite quail.

Four experiments were conducted to determine the suitability of various debeaking procedures for Bobwhite quail at hatching or at one week of age. Two experiments were conducted using a "precision" type debeaking method with the following treatments: control; debeaked at hatching with debeaker guide plate holes of 2.38 or 2.78 mm; debeaked at seven days of age using guide plate holes of 2.38, 2.78 or 3.18 mm. Two experiments tested a "touch-burn" method at hatching with the following treatments: control; burned 1/4 distance to nares; and burned 1/2 distance to nares. The "precision" type methods at hatching or seven days of aged reduced mortality from cannibalism; however, these methods were found to be relatively slow and difficult, and the birds lacked uniformity in beak and body size at five weeks of age. Burning 1/2 distance to nares was too severe, causing a reduction in body weight and poor feed efficiency. Burning 1/4 distanct to nares gave the most favorable results: growth and feed efficiency as good or better than controls, uniform birds and decreased cannibalism.

Animals↗

Determination of free malonaldehyde formed in liver microsomes upon CCl4 oxidation.

Free malonaldehyde formed in the microsomes prepared from livers of monkey, rat, rabbit, mouse, cow, pig, dog, sheep and horse upon CCl4 oxidation was derivatized by reaction with N-methylhydrazine to form 1-methylpyrazole which was subsequently analyzed by capillary gas chromatography. Among the livers from animals tested, the monkey and rat livers produced the most malonaldehyde upon CCl4 treatment. Horse liver showed the greatest resistance to CCl4 oxidation. The gas chromatography method used in the present study exhibited an accurate and specific measurement of free malonaldehyde that might provide an understanding of the biochemical process of in vitro lipid peroxidation.

Animals↗

Automated analysis of toxicant-induced changes in rat sperm head morphometry.

An automated sperm morphometry analysis (ASMA) instrument was developed to obtain measurements of toxicant-induced changes in rat sperm head morphometry. 1,3-dinitrobenzene (1,3-DNB), a testicular toxicant known to affect sperm parameters, was used. Twelve-week-old Sprague-Dawley rats were allocated to a control (C) and to two 1,3-DNB treatment groups (T1 = 15 mg/kg; T2 = 25 mg/kg). 1,3-DNB was administered as a single dose by gavage, and animals were sacrificed 22 days after exposure. Sperm were collected, and morphology smears were made by a standard method. One hundred sperm heads were digitized on each slide, and 8 metric measurements were automatically reported. All measurements tended to decrease in a dose-dependent manner with increasing doses of 1,3-DNB. All values for total width (Wa) and interior width (W(e)) were significantly different from one another. Wa/L was significantly larger in the control than in T1 or T2, and symmetry (S = Wb/Wa) was significantly smaller in the control than in T1 or T2. Multivariate cluster analysis revealed three subpopulations that were also visually distinct. Subpopulation no. 1 was normal, based on published descriptions of normal rat sperm; subpopulation no. 2 was abnormal with a flattened curvature and a normal length; subpopulation no. 3 was abnormal with a foreshortened length and a flattened curvature. T1 and T2 contained significantly more sperm from subpopulation no. 2 and no. 3 than C (T1 = 22% and T2 = 34% vs. C = 8% by cluster analysis). C had 93% normal sperm, while the treatments had 78% and 66%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗