Search PubMed⌕ Search

Biomedical subjects

M H Miller

Publications and source records attributed to M H Miller.

At least 91 records · Page 5Linked to original sources
PubMed1987

Lack of beneficial effect of intensive topical steroids and beta irradiation of eyes undergoing repeat trabeculectomy.

Sixteen eyes (14 patients) that had previous failed trabeculectomy underwent a further trabeculectomy. In the postoperative period they were treated with intensive topical steroids (hourly) for several months. At the end of one year the overall results of surgery were not improved using this regime when compared with a previously reported series of similar patients who were treated with less steroid. It appeared that the addition of more intensive topical steroid usage was no more successful than steroids given in a four-time-a-day program. Additionally, some eyes were treated with beta irradiation, which did not appear to influence the results. Eyes that had a limbus-based conjunctival flap at reoperation had a more favorable outcome than those having fornix-based flaps.

Administration, Topical↗
PubMed1986

Penicillin-induced effects on streptomycin uptake and early bactericidal activity differ in viridans group and enterococcal streptococci.

In vitro studies with penicillin and [3H]streptomycin in four strains of streptococci (S. faecalis, S. sanguis, and S. mitis) were performed by simultaneously measuring the rates of bacterial killing and uptake of streptomycin. In S. faecalis, penicillin stimulated streptomycin uptake, as has been shown by Moellering and Weinberg (R. C. Moellering, Jr., and A. N. Weinberg, J. Clin. Invest. 50:2580-2584, 1971). Moreover, the antibiotic combination was associated with an enhanced bactericidal rate which temporally correlated with beta-lactam-induced aminoglycoside uptake. In contrast, in viridans group streptococci (S. sanguis and S. mitis) penicillin had no effect on streptomycin uptake and a minimal effect on bactericidal rate when compared with either drug alone. These data suggested that the stimulation of streptomycin uptake in streptococci by penicillin is strain or species specific and that important differences exist between enterococci and viridans group streptococci regarding the mechanisms of beta-lactam-aminoglycoside potentiation.

Aminoglycosides↗
PubMed1986

In vitro studies simultaneously examining effect of oxacillin on uptake of radiolabeled streptomycin and on associated bacterial lethality in Staphylococcus aureus.

We studied the effects of various concentrations of oxacillin on streptomycin uptake and killing for several strains of Staphylococcus aureus. When streptomycin was present in concentrations below the MIC, addition of oxacillin at concentrations greater than or equal to the MIC was associated with both significantly increased aminoglycoside uptake and killing. In contrast, when streptomycin was present in concentrations above the MIC, no increase of streptomycin uptake was noted with the addition of oxacillin, and killing was no greater than what would have been expected with a simply additive effect. Similar studies in a strain of S. aureus selected for high-level streptomycin resistance also demonstrated increased streptomycin uptake in the presence of concentrations of oxacillin above the MIC; however, killing was no greater than that seen with oxacillin alone. These studies provide data which are potentially important in designing a rational approach to clinical use of combination antibiotic therapy.

Dose-Response Relationship, Drug↗
PubMed1986

Restoring hearing to the older patient: the physician's role.

There is growing evidence that failure to diagnose and manage hearing problems early in their course results in significant and--to some extent--irreversible sensory deprivation. The primary care physician should routinely screen patients over age 50 for pure-tone sensitivity as part of the general physical examination. Battery-operated, in-office, limited-frequency audiometers are available for under $350.

Aged↗
PubMed1985

A light-guidance system to be used for CT-guided biopsy.

We describe a light-guidance system that uses intersecting helium-neon laser beams to provide precise guidance for biopsy approaches from any direction (including compound angles) during CT-guided biopsy of the chest and abdomen. Interactive software provides visualization of the proposed path, indicates the segment of that path that will pass through each section, and displays the settings for the apparatus.

Biopsy, Needle↗
PubMed1985

Distribution of pneumothorax in the supine and semirecumbent critically ill adult.

Although a number of radiologic signs of pneumothorax in the supine patient have been reported, the frequency of involvement of various pleural recesses has not been emphasized. In 88 critically ill patients with 112 pneumothoraces, the anteromedial (38%) and subpulmonic (26%) recesses were the most commonly involved in the supine and semirecumbent position. In this study, 30% of pneumothoraces were not initially detected by the clinician or radiologist, and half of these progressed to tension pneumothorax. Knowledge of the most common recesses involved in pneumothorax and aggressive use of additional radiographic views, including computed tomography, should increase detection of pneumothoraces in critically ill patients.

Adult↗
PubMed1985

Academic inbreeding in nursing: intentional or inevitable?

Consensus exists that academic inbreeding inhibits innovation and scholarly achievement. Nevertheless, schools of nursing have been--and continue to be--more inbred than other schools within the university. In a follow-up survey to Miller and Ehnes' 1977 study, inbreeding has increased slightly--more junior than senior faculty are inbred, and rapidly expanding schools are the most inbred. A comparison of two schools (one highly inbred and one less so) demonstrates that schools do not recruit faculty from other schools in their region. The paper concludes that economic pressures may force deans to hire their own graduates (reducing recruitment costs) for junior positions and pay a relatively larger sum for a few senior level outbred faculty. Thus, academic inbreeding in nursing may be both inevitable and intentional.

Education, Nursing, Graduate↗
PubMed1985

An animal model of filtration surgery.

An animal model for glaucoma fistulising surgery is described. The model is designed to fail after a few weeks. It is suggested that the model may be used to investigate the effects of topical or systemic agents on the results of glaucoma surgery. The preliminary results of intraocular pressure and facility of outflow in the control group of rabbits are presented.

Animals↗
PubMed1985

Clinical comparison of cultured human epithelial cells and rat liver as substrates for the fluorescent antinuclear antibody test.

Fluorescent antinuclear antibody (ANA) testing was performed on 141 sera from 114 patients with well defined rheumatic diseases including fibrositis syndrome and 24 sera from 24 healthy subjects using HEp-2 cells and rat liver as substrates. ANA titers were almost always higher on HEp-2, in most cases by 1:5 dilutions. ANA positivity or negativity was usually substrate independent, but there were exceptions. Two patients with SLE were ANA positive on HEp-2 only and rat liver only, respectively; patterns were homogeneous. Thirteen of 15 CREST patients had anticentromere antibodies, detected on HEp-2 only. "False-positive" ANA were invariably low titer, speckled and confined to one substrate.

Animals↗
PubMed1984

Gentamicin uptake in Staphylococcus aureus possessing plasmid-encoded, aminoglycoside-modifying enzymes.

[3H]gentamicin uptake and killing were studied in three strains of gentamicin-resistant Staphylococcus aureus possessing plasmid-encoded, gentamicin-modifying enzymes and in three isogenic, enzyme-free, gentamicin-susceptible derivatives. At low (less than or equal to 2.0 micrograms/ml) concentrations of gentamicin, uptake by resistant organisms was impaired compared with that of susceptible strains, and no killing was noted. In contrast, at higher (2.5 to 10.0 micrograms/ml) concentrations (which were below the MIC for the resistant strains), rapid gentamicin uptake similar to that seen in susceptible isolates was observed. Although growth inhibition at these concentrations was apparent, there was no loss of viability in resistant strains. Consistently, the membrane H+-ATPase inhibitor N,N'-dicyclohexyl carbodiimide caused resistant strains to take up low concentrations (1.0 microgram/ml) of gentamicin at rates comparable to those seen in susceptible organisms without causing an associated loss of viability. These studies show differences between gentamicin uptake in S. aureus and streptomycin uptake in Escherichia coli (Dickie et al., Antimicrob. Agents Chemother. 14:569-580, 1978) regarding the kinetics of uptake in resistant strains with plasmid-encoded aminoglycoside-modifying enzymes. Specifically, they suggest that for 2-deoxystreptamine compounds such as gentamicin, ribosomal binding followed by accelerated uptake and subsequent interference with cell growth may occur without invariably being associated with lethal effect.

Dicyclohexylcarbodiimide↗
PubMed1984

Quantitative association between electrical potential across the cytoplasmic membrane and early gentamicin uptake and killing in Staphylococcus aureus.

The relationship between the magnitude of the transmembrane electrical potential and the uptake of [14C]gentamicin was examined in wild-type Staphylococcus aureus in the logarithmic phase of growth. The electrical potential (delta psi) and the pH gradient across the cell membrane were determined by measuring the equilibrium distribution of [3H]tetraphenyl-phosphonium and [14C]acetylsalicylic acid, respectively. Incubation in the presence of the H+-ATPase inhibitor N,N'-dicyclohexylcarbodiimide (DCCD) led to an increase in delta psi with no measurable effect on the pH gradient at external pHs ranging from 5.0 to 6.5, and the effect on delta psi was DCCD concentration dependent. In separate experiments, gentamicin uptake and killing were studied in the same cells under identical conditions. At pH 5.0 (delta psi = -140 mV), no gentamicin uptake occurred. In the presence of 40 and 100 microM DCCD, delta psi was increased to -162 and -184 mV, respectively, and gentamicin uptake was observed in a manner that was also dependent on the DCCD concentration. At pH 6.0 (delta psi = -164 mV), gentamicin uptake occurred in the absence of the carbodiimide but was enhanced in a concentration-dependent fashion by 40 and 100 microM DCCD (delta psi = -174 and -216 mV, respectively). In all cases increased gentamicin uptake was associated with an enhanced bactericidal effect. The results indicate that initiation of gentamicin uptake requires a threshold level of delta psi (-155 mV) and that above this level drug uptake is directly dependent on the magnitude of delta psi.

Biological Transport↗
PubMed1984

Lumbar spine: pretest predictability of CT findings.

Demographic and symptomatic data gathered from 460 patients referred for lumbosacral CT examinations were analyzed to determine if the prescan probability of normal or abnormal findings could be predicted accurately. We were unable to predict the presence of herniated disk on the basis of patient-supplied data alone. Age was the single most significant predictor of an abnormality and was sharply related to degenerative disease and spinal stenosis.

Adult↗
PubMed1984

CT detection of occult pneumothorax in head trauma.

A prospective evaluation for occult pneumothorax was performed in 25 consecutive patients with serious head trauma by combining a limited chest CT examination with the emergency head CT examination. Of 21 pneumothoraces present in 15 patients, 11 (52%) were found only by chest CT and were not identified clinically or by supine chest radiograph. Because of pending therapeutic measures, chest tubes were placed in nine of the 11 occult pneumothoraces, regardless of the volume. Chest CT proved itself as the most sensitive method for detection of occult pneumothorax, permitting early chest tube placement to prevent transition to a tension pneumothorax during subsequent mechanical ventilation or emergency surgery under general anesthesia.

Craniocerebral Trauma↗