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R D Miller

Publications and source records attributed to R D Miller.

At least 145 records · Page 8Linked to original sources
PubMed1991

The presentation of expert testimony via live audio-visual communication.

As part of a national effort to improve efficiency in court procedures, the American Bar Association has recommended, on the basis of a number of pilot studies, increased use of current audio-visual technology, such as telephone and live video communication, to eliminate delays caused by unavailability of participants in both civil and criminal procedures. Although these recommendations were made to facilitate court proceedings, and for the convenience of attorneys and judges, they also have the potential to save significant time for clinical expert witnesses as well. The author reviews the studies of telephone testimony that were done by the American Bar Association and other legal research groups, as well as the experience in one state forensic evaluation and treatment center. He also reviewed the case law on the issue of remote testimony. He then presents data from a national survey of state attorneys general concerning the admissibility of testimony via audio-visual means, including video depositions. Finally, he concludes that the option to testify by telephone provides a significant savings in precious clinical time for forensic clinicians in public facilities, and urges that such clinicians work actively to convince courts and/or legislatures in states that do not permit such testimony (currently the majority), to consider accepting it, to improve the effective use of scarce clinical resources in public facilities.

Expert Testimony↗
PubMed1990

Interactions of virulent and avirulent Legionella pneumophila with human monocytes.

Four pairs of virulent/avirulent strains of Legionella pneumophila were examined for their adherence/uptake and activation of human monocytes. Oxidative metabolic responses of monocytes were quantitated by measuring intracellular hydrogen peroxide generation using flow cytometry and by assessment of superoxide dismutase-inhibitable superoxide anion generation. All L. pneumophila strains induced less of a response than did Escherichia coli. Within each pair of isolates, virulent strains of L. pneumophila stimulated the oxidative response of monocytes less than avirulent variants. To determine effects of complement fixation by each strain on their adherence to monocytes, a phagocytic index (PI) was determined under various conditions. In autologous donor serum (AS), all L. pneumophila strains had a PI in the range of 2.1-3.1 bacteria per monocyte, with E. coli having a PI of 9.1. No significant differences were observed between virulent L. pneumophila strains and their avirulent variants. In the presence of heat-inactivated AS, all PI fell to 0.13-0.20 for the L. pneumophila strains, and to 2.16 for E. coli. Using heat-inactivated AS reconstituted with exogenous human complement as a source of opsonization, levels of PI were indistinguishable from their respective levels in AS. This suggests that complement fixation plays an important role in the adherence of virulent and avirulent L. pneumophila to human monocytes.

Bacterial Adhesion↗
PubMed1990

The effect of enrollment in a prepaid health plan on utilization of a community crisis intervention center by chronically mentally ill individuals.

When a prepaid Medicaid Demonstration Project was initiated in Hennepin County, Minnesota, concerns were raised that the new system might place an additional service burden on County-funded mental health agencies responding to underprovision of mental health services by prepaid health plans. This study examined the use of a single County mental health services agency, the Crisis Intervention Center, by a group of vulnerable and frequent users, the chronically mentally ill. The study found that use of the Center by persons enrolled in a prepaid plan declined after enrollment and was different and lower for the prepaid group than for a comparison group of fee-for-service system users during the same time periods. The difference did not meet conventional levels of statistical significance. This finding is nonetheless important since it may be an indication of successful case management by prepaid health plans in serving chronically mentally ill individuals.

Adult↗
PubMed1990

Inhibition of polymorphonuclear leukocyte function by Legionella pneumophila exoproducts.

Total exoproducts (relative molecular mass greater than 10,000) from wild-type strains of Legionella pneumophila markedly inhibited human polymorphonuclear leukocyte (PMN) superoxide anion generation, at sub-lethal concentrations, in response to four stimuli [1.7, 0, 0.6 and 3.4% of control for zymosan activated particles (ZAP), phorbol myristate acetate (PMA), calcium ionophore (A 23187), and formyl-methionyl-leucyl-phenylalanine (fMLP), respectively]. PMN chemotaxis towards fMLP and spontaneous migration, were also dramatically inhibited (2.8 and 2.9% of buffer-treated controls, respectively). In contrast, total exoproducts from the cas-1 strain of L. pneumophila, a protease-deficient mutant generated by ethyl methane sulfonate mutagenesis, failed to inhibit PMN superoxide production in response to ZAP and PMA and only partially inhibited PMN response to A 23187 and fMLP. PMN spontaneous migration was unaffected by treatment with total exoproducts from the mutant, while directed chemotaxis was partially inhibited (51.4%). These data demonstrated that L. pneumophila total exoproducts, primarily protease had significant inhibitory effects on normal PMN function and may play an important contributory role in the pathogenesis of legionnaire's disease.

Calcimycin↗
PubMed1990

Cloning and characterization of the human beta-glucuronidase gene.

We have isolated a cosmid clone that contains GUSB, the human gene encoding beta-glucuronidase. The 21-kb gene contains 12 exons ranging from 85 to 376 bp in length. Exon 6 corresponds to the 153-bp deletion in the shorter of two types of cDNAs reported earlier, supporting the hypothesis that this cDNA arose by alternate splicing leading to exon skipping. The insert contains 4.2 kb of sequence upstream from the first exon and 6 kb 3' of the last exon. The clone expresses human beta-glucuronidase in stably transformed rat XCtk- cells. Comparison of the human gene organization with that recently reported for the murine beta-glucuronidase gene revealed that the intron/exon boundaries are identical. In the splice junctions, the most highly conserved regions are those identified as consensus sequences, and these are at least as highly conserved as bases encoding the translated portion of the gene.

Animals↗
PubMed1990

Cerebrospinal fluid concentrations of laudanosine after administration of atracurium.

The concentration of laudanosine in cerebrospinal fluid (CSF) was measured in four patients undergoing brain electrode placement after the administration of atracurium. CSF: plasma laudanosine concentration ratios ranged from less than 1 to 14%, with a range of CSF laudanosine concentrations of less than 2-14 ng ml-1. One patient had no detectable laudanosine in CSF, but sampling in this patient was possible for only 30 min. There was no atracurium detectable in the CSF of any patient. We conclude that laudanosine crosses the blood-brain barrier and further study of its central nervous system effects in man is warranted.

Anesthesia, General↗
PubMed1990

Evidence for regulation of the autoimmune anti-erythrocyte response by idiotype-specific suppressor T cells in NZB mice.

The present study demonstrates that specific CD8+, CD4- suppressor T cells (Ts) actively regulate the autoimmune anti-mouse red blood cell (MRBC) antibody response in spleen cell populations of young, Coombs-negative NZB mice. These Ts appear to bind a monoclonal NZB autoantibody (G-8 mAb) to unmodified MRBC which expresses a dominant idiotype (Id) in the spontaneous anti-MRBC autoantibody response of NZB mice. Treatment of normally nonauto-responsive spleen cells from young NZB mice with the G-8 mAb + C prior to culture allows these cells to develop, in 4-5 days, an autoantibody response to MRBC. The level of response obtained after depletion of the G-8-binding cells is comparable with that obtained after generalized depletion of Ts by treatment with anti-CD8 + C, suggesting that the G-8-binding cells make up a major portion of the regulatory Ts in this response. Yet, G-8 + C treatment depletes a very small subset of cells and not the total CD8+ T cell population. The regulatory cells appear to be neither isotype nor allotype specific, nor do they appear to have MRBC antigens bound to or expressed on their membranes. Rather, these cells are more likely G-8 idiotype specific. The regulatory G-8-binding cells are CD8+ T cells, not B cells. Furthermore, Ts-enriched populations when depleted of G-8-binding cells lose their ability to suppress in vitro anti-MRBC responses of spleen cells from Coombs-negative NZB mice depleted of CD8+ cells, as well as those of unfractionated spleen cells from Coombs-positive NZB mice.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1990

Pharmacokinetics and pharmacodynamics of atracurium in the elderly.

To evaluate the effect of aging on the distribution, clearance, and neuromuscular junction sensitivity to atracurium, the authors determined the pharmacokinetics and pharmacodynamics of atracurium in five healthy elderly subjects (74-76 yr) during halothane-nitrous oxide anesthesia and compared these values to those obtained previously in five healthy young adults (22-44 yr). A brief (6.0-13.0 min) infusion of atracurium was administered until twitch tension was suppressed by approximately 70%, and atracurium plasma concentration and twitch tension data were used to determine pharmacokinetic and pharmacodynamic parameters for each patient. Total clearance (Cltotal) was similar in elderly and young adults. However, clearance via the liver and/or kidney (Clorgan) was lower in elderly patients, whereas clearance due to Hofmann elimination and ester hydrolysis (Clnonorgan) was higher. Volume of distribution at steady state (Vss) was larger in elderly patients. The increase in Vss without an age-related increase in Cltotal resulted in a longer elimination half-life [21.8 (+)/- 3.3 vs. 15.7 (+)/- 2.5 min (mean (+)/- SD)] in elderly patients. The steady state plasma concentration of atracurium required to suppress twitch tension by 50% was similar in elderly and young adults. The authors conclude that the pharmacokinetics, but not the pharmacodynamics, of atracurium differ significantly between elderly and young adults. As a result, repeated doses will be required with similar frequency in young and elderly adults, but recovery from comparable levels of neuromuscular blockade may be slightly prolonged in elderly patients.

Adult↗
PubMed1990

The neuromuscular blocking effects and pharmacokinetics of ORG 9426 and ORG 9616 in the cat.

The neuromuscular blocking effects and pharmacokinetics of ORG 9426, 1.5 mg/kg and ORG 9616, 1.2 mg/kg iv, two new nondepolarizing neuromuscular blocking drugs, were studied in 28 cats (i.e., 14 cats with each drug) with and without renal pedicle ligation. A gas chromatographic assay was used to determine the concentrations of ORG 9426 and ORG 9616 and its desacetyl metabolites in plasma, urine, bile, and liver. The duration of neuromuscular blockade of both drugs was not altered by ligation of renal pedicles. Plasma clearance of ORG 9426 was slower in cats with ligated renal pedicles (P less than 0.01). With ORG 9616, mean elimination half-life was slower and mean residence time longer in cats with renal pedicle ligation. Otherwise, there was no significant differences with any pharmacokinetic variables in cats with and without renal pedicle ligation. Only 8.7 +/- 5.7% (SD) and 6.0 +/- 2.8% of an injected dose of ORG 9426 and ORG 9616 was excreted into the urine, respectively. Conversely, 54.4 +/- 9.2% and 52.4 +/- 9.2% of an injected dose of ORG 9426 and 35.7 +/- 12.2% and 46.8 +/- 9.7% of ORG 9616 were excreted into the bile in cats without and with renal pedicle ligation, respectively. Finally, 21.3 +/- 6.5% and 33.5 +/- 15.6% of ORG 9426 and 14.0 +/- 3.2% and 18.1 +/- 5.6% of ORG 9616 were in the liver 6 h after injection in cats without and with renal pedicle ligation respectively. The authors were able to account for the biodisposition of 84.4% and 85.9% of an injected dose of ORG 9426 in cats without and with renal pedicle ligation respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Androstanols↗
PubMed1990

The effect of local surface and central cooling on adductor pollicis twitch tension during nitrous oxide/isoflurane and nitrous oxide/fentanyl anesthesia in humans.

This study aimed to determine whether: 1) the method of cooling the hand (i.e. central [total body] vs. local surface [hand only]) influences the relationship between the adductor pollicis temperature and twitch tension; and 2) decreased evoked twitch response during hypothermia is due to reduced muscle temperature and/or the anesthetic drug used. First, the effect of local surface cooling on adductor pollicis twitch tension during isoflurane anesthesia was determined in 15 patients, while central body temperature was not allowed to decrease. Adductor pollicis temperature and twitch tension decreased in a linear manner (P less than 0.05). However, the magnitude of the decreased response was only 43% of that observed during central cooling in the authors' previous study under otherwise similar experimental conditions. Second, the effect of central cooling on adductor pollicis twitch tension during nitrous oxide/fentanyl anesthesia was determined in five patients. The twitch tension did not decrease until the adductor pollicis temperature decreased below 35.2 degrees C. Below this temperature, twitch tension decreased 16%/degrees C reduction in muscle temperature. These results are similar to those obtained in the authors' previous study in patients anesthetized with nitrous oxide/isoflurane anesthesia. The authors conclude that both central and local surface cooling of the adductor pollicis muscle reduces twitch tension and that the decrease in adductor pollicis twitch tension is the same during nitrous oxide/isoflurane and nitrous oxide/fentanyl anesthesia.

Adult↗
PubMed1990

Pharmacokinetics and pharmacodynamics of atracurium in infants and children.

To determine whether maturational changes in body composition and organ function affect distribution and elimination of and sensitivity to atracurium, the authors determined the pharmacokinetics and pharmacodynamics of atracurium in six infants and five children and compared these results with those obtained in five adults. Atracurium, 15.8 +/- 1.7 micrograms.kg-1.min-1, was infused iv for 6-11 min to subjects anesthetized with nitrous oxide (60%) and halothane (0.9 MAC, age-adjusted) and twitch tension of the adductor pollicis muscle was measured. Plasma samples were obtained for 120 min; concentrations of atracurium were determined using a liquid chromatographic assay. A two-compartment pharmacokinetic model, adapted to account for elimination of atracurium from both central and peripheral compartments, was fit to the plasma concentration data; an effect-compartment model was fit to the twitch tension data. Volume of distribution at steady state (210 +/- 118, 129 +/- 44, and 100 +/- 22 ml/kg for infants, children, and adults, respectively) and total clearance (7.9 +/- 2.0, 6.8 +/- 1.6, and 5.3 +/- 0.9 ml.kg-1.min-1 for the three groups) decreased with increasing age. Neither elimination half-life (20.0 +/- 5.1, 17.2 +/- 5.1, and 15.7 +/- 2.5 min for the three groups) nor the steady state plasma concentration that resulted in 50% neuromuscular blockade (363 +/- 118, 444 +/- 121, and 436 +/- 122 ng/ml for the three groups) varied with age. The authors conclude that these results are consistent with and explain the previously reported findings that recovery from the neuromuscular effects of atracurium is minimally affected by age.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Can early administration of neostigmine, in single or repeated doses, alter the course of neuromuscular recovery from a vecuronium-induced neuromuscular blockade?

The authors sought to determine whether neostigmine, given at a time when no response to peripheral nerve stimulation could be elicited, hastened recovery from a vecuronium-induced neuromuscular blockade (NMB). The effect of neostigmine (70 micrograms/kg) in antagonizing a profound (no-twitch) vecuronium-induced (0.1 mg/kg) NMB in 40 healthy patients was studied. Patients were randomly assigned to one of four groups specifying the sequence of neostigmine administration. Fifteen minutes after the administration of vecuronium, when there was no detectable twitch response, each patient received either neostigmine (70 micrograms/kg) with glycopyrrolate (15 micrograms/kg) or an equivalent volume of normal saline (placebo). When T1 (the first response in the train-of-four [TOF] sequence) recovered to 10% of control, patients again received either neostigmine with glycopyrrolate in the same doses as before or the placebo. The following variables were measured: times from vecuronium injection until T1 recovered to 10% (t [10]) and 90% (t [90]) of control, and time until the TOF ratio was equal to 75% (t [TOF75]). Mean values of t (90) and t (TOF75) were shorter (54.7-75.2 min and 60.4-79.5 min, respectively) for the three groups who received neostigmine as compared with patients who received two doses of placebo (104.3 and 122.6 min, respectively). There were no differences in the t (90) and t (TOF75) values among the three groups who received neostigmine.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Cardiovascular and neuromuscular effects of three steroidal neuromuscular blocking drugs in dogs (ORG 9616, ORG 9426, ORG 9991).

Developmental research has been directed toward creating nondepolarizing muscle relaxants with an onset time and duration of actions shorter than that of vecuronium or atracurium. We determined the cardiovascular and neuromuscular effects of three new and promising nondepolarizing muscle relaxants in six dogs anesthetized with halothane. Each dog was anesthetized four times (each time separated from the others by at least 1 wk); one muscle relaxant was studied each time. Three doses (one, three, and five times the ED90) were given as intravenous bolus injections. ORG 9616 and ORG 9991 had shorter durations of action than ORG 9426. The duration of action of the doses that were five times the ED90 was 18 +/- 5.88 and 15.8 +/- 4.41 min (mean +/- SD) with ORG 9616 and ORG 9991, respectively, as compared with 39.7 +/- 17.15 min with ORG 9426 (P less than 0.05). ORG 9426 was virtually free of cardiovascular effects. The ED90 doses of ORG 9616 and ORG 9991 did not cause cardiovascular effects; the doses of three and five times the ED90 caused small decreases in mean arterial blood pressure and increases in heart rate. Mean arterial blood pressure decreased from 99 +/- 10.2 to 88 +/- 13.1 mm Hg and from 98 +/- 11.7 to 77 +/- 8.1 mm Hg with five times the ED90 dose of ORG 9616 and ORG 9991, respectively. The authors conclude that ORG 9426 has a duration of neuromuscular blockade that is probably similar to vecuronium, and one that is free of cardiovascular effects.(ABSTRACT TRUNCATED AT 250 WORDS)

Androstanols↗
PubMed1990

Pitfalls in state-authorized treatment of minors.

Recently a federal court in Georgia ruled that several physicians and several state officials could be sued for state-authorized treatment of a minor over his father's objection. State authorization protects providers only if it is properly obtained and the authorizing official has the power to grant the authorization in the existing circumstances.

Adolescent↗
PubMed1990

Who's afraid of forensic psychiatry?

Forensic psychiatry has come under mounting criticism from the press and other medical professionals, largely for its participation in the insanity defense. The author argues that the expertise available from the specialty is of increasing importance to psychiatry as a whole, as more and more legal issues become relevant to the practice of general psychiatry, and should be actively encouraged and legitimized rather than ostracized. All psychiatrists should be exposed to forensic principles and practices during their training, and the ability of forensic psychiatrists to serve as transducers between the clinical and the legal/judicial should be increasingly used to present the clinical viewpoint effectively in courts and legislatures.

Ethics, Medical↗
PubMed1990

Prearraignment forensic evaluation: the odyssey moves east of the Pecos.

Although the ethical guidelines of both the American Psychiatric Association and the American Academy of Psychiatry and the Law explicitly prohibit the forensic examination of criminal defendants before appointment of counsel, except for the purpose of providing emergency medical care and treatment, the practice continues in many parts of the country. This article presents a recent case in which this practice was challenged on appeal, to serve as a focus for discussion of the evolution of, and rationales for and against, these ethical positions. It will also serve as a focus to examine the legal views concerning such examinations, derived from the appeal of the decision in the case itself as well as decisions in similar cases.

Borderline Personality Disorder↗