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Biomedical subjects

L Taylor

Publications and source records attributed to L Taylor.

At least 181 records · Page 10Linked to original sources
PubMed1992

Developmental changes in the recognition and comprehension of facial expression: implications for frontal lobe function.

Children aged 6-15 years old and adults (over 18) were given three tests designed to test perception and comprehension of facial expression. In the first test subjects were given two composite symmetrical faces made from the left or right half of a normal face, the subjects' task being to indicate which composite more closely resembled the original face. In the second test the subjects matched a series of photographs from Life magazine with key photographs of one of six distinct emotions (sad, fear, happy, anger, disgust, surprise). In the third test the subjects chose a key photograph that was appropriate for the face of a faceless character in a cartoon. On the composite faces test the subjects in all groups exhibited a preference for the left visual field composite, implying that all age groups were processing the faces in a similar manner. The results of the other two tests showed that there was an improvement in the perception of facial expression between the ages of 6 and 8 years, little change until about 13 years, and then a second improvement to adult performance at about 14 years. The performance of the 8- to 13-year-old children was similar to that of adult patients with frontal lobe injuries, which could be taken as evidence that the regions of the frontal lobe involved in the performance of these tasks may not be mature until about 14 years of age.

Adult↗
PubMed1992

Relationship between affect and memory: motivation-based selective generation.

Two experiments examined the influence of anger and retaliatory motivation on memory for negative material. In the 1st study, 60 male undergraduates memorized words with positive, negative, and neutral semantic connotations. It was found that angered men who expected to retaliate against their provocateur recalled more negative words than other words, and more than Ss in all other affect and evaluation conditions. Angered men in the nonretaliation condition displayed no differences in negative word recall. The 2nd experiment investigated memory for details of a provoking experience. Angered men who expected to retaliate more accurately recalled the details of their provocation, but whether they were given the retaliation information before or after provocation had no bearing on memory for these details. Results are discussed in terms of a motivation-based selective generation hypothesis for the relationship between anger and memory.

Adult↗
PubMed1992

Clinical efficacy of spinal instrumentation in lumbar degenerative disc disease.

In review of 871 lumbar fusion procedures performed during the last 8 years, the theoretical advantages of lumbar spinal instrumentation are not borne out in simple discogenic disease. Four groups of 30-35 patients without previous surgery who underwent fusion by different techniques were matched for age, sex, length of follow-up, surgeons, number of levels fused, duration of preoperative symptoms, diagnosis, and type of third party payer. At least for the diagnoses of herniated disc with segmental instability and the instrumentation systems used in this study, results were superior with no internal fixation. This is in keeping with the higher complication rates and frequent need for implant removal reported by many authors.

Adult↗
PubMed1992

A skills programme for preclinical medical students.

An education programme in which preclinical medical students are introduced to common procedural skills is described. This programme is presented by a multidisciplinary health care team using short lectures, demonstrations, mannequin practice, and, in selected instances, practice on class-mate volunteers. The programme was evaluated by the students immediately following the presentation and for one class during their clinical activities one year later. The students' support for this programme was generally enthusiastic and remained undiminished upon reflection 12 months later.

Attitude of Health Personnel↗
PubMed1992

Ability of surrogates to represent satisfaction of nursing home residents with quality of care.

OBJECTIVE: To measure the ability of surrogates to accurately represent nursing home residents' satisfaction with the nursing home care. DESIGN: Comparison by correlation analysis of questionnaire answers by nursing-home residents and their designated surrogates. SETTING: Four non-profit community nursing homes. PARTICIPANTS: One-hundred fifty-two resident-surrogate pairs were included, based on the following criteria: (1) the resident was able to respond to questions verbally and in English, had cognitive abilities sufficient to understand the questions, and had a responsible party who had a telephone number in the medical record; (2) both the resident and the surrogate agreed to be interviewed. OUTCOME MEASURES: A 26-item instrument (21 specific and 5 global items) was developed to measure surrogates' perceptions of residents' satisfaction with the quality of the physician services, nursing care, and the nursing home environment. The instrument was scored on a 4-point Likert scale in which higher scores indicated greater satisfaction and paralleled a similar instrument designed for nursing home residents. Correlation of residents' with surrogates' scores on the satisfaction instruments was examined. RESULTS: The mean score for most items was greater than 3.0, indicating overall satisfaction with the care. Correlations between surrogates and residents on specific items ranged from 0.1 to 0.55. Correlations were highest for global items and items addressing satisfaction with the environment. CONCLUSION: We conclude that nursing home residents' surrogates cannot accurately express the residents' satisfaction with all areas of nursing home care and that their evaluations should not be taken in lieu of the residents' opinions.

Aged↗
PubMed1992

Measurement of cold challenge responses in primary Raynaud's phenomenon and Raynaud's phenomenon associated with systemic sclerosis.

Using computed thermography continuous temperature recordings were made before and after cold challenge of the fingers of control subjects and patients with primary Raynaud's phenomenon and Raynaud's phenomenon associated with systemic sclerosis. Basal skin temperature measurements (Tpre) were significantly lower in patients with primary Raynaud's phenomenon and Raynaud's phenomenon associated with systemic sclerosis than in the controls. Temperatures immediately after cold challenge (T0) were significantly lower in patients with primary Raynaud's phenomenon and Raynaud's phenomenon associated with systemic sclerosis than in controls. The lag phase before the start of temperature recovery (Tlag) was significantly greater in patients with primary Raynaud's phenomenon and Raynaud's phenomenon associated with systemic sclerosis than in control subjects. The maximum recovery index (R%) was significantly less in patients with primary Raynaud's phenomenon and Raynaud's phenomenon associated with systemic sclerosis than in controls. The maximum rate of change of temperature during the rapid phase of rewarming (Gmax) was significantly greater in controls than in patients with primary Raynaud's phenomenon and Raynaud's phenomenon associated with systemic sclerosis. Discriminant analysis showed that the dynamic parameters of rewarming (Tlag, Gmax, and R%) showed greater variation between the patients with primary Raynaud's phenomenon and those with Raynaud's phenomenon associated with systemic sclerosis than did Tpre or T0. This method of analysis of cold challenge will be used in studies of the effects of treatment of Raynaud's phenomenon.

Adult↗
PubMed1992

Isolation of monochromosomal hybrids following fusion of human diploid fibroblast-derived microcells with mouse A9 cells.

Rodent x human hybrids containing single human chromosomes are valuable tools in the study of human genetics. Using a retrovirus carrying the neomycin gene, we generated a neomycin-resistant (neor) pool of human diploid fibroblasts. Following fusion of microcells prepared from this pool to mouse A9 cells, we obtained four neor hybrids containing a single human chromosome 2, 3, 5, or 15.

Animals↗
PubMed1992

Does aging affect liver microtubules?

Microtubules are essential for many cell processes, e.g., ligand-receptor endocytosis and the vectorial movement of endosomes. The cytoskeleton, particularly microtubules, may undergo age-related changes that are reflected in cell dysfunctions. For example, the translocation of 125I-IgA-containing vesicles from the sinusoidal surface to the pericanalicular cytoplasm is reduced (greater than 40%) in old versus young rats. Electron microscopic analysis demonstrated that the concentration of microtubule profiles in young animals is within 10-20% of that in old rats. The relative concentration of polymerized tubulin declines greater than 70% by 12 months of age, but the total tubulin content remains unchanged until later, i.e., declining 50% by 24 months. Concomitant increases occur in the free fractions of microtubule-associated proteins (MAP), i.e., MAP1 and heat-stable MAPS. These fractions are not associated with polymerized tubulin. The declines in total and polymerized tubulin, together with the increases in the MAPS' free fractions, may be indicative of fewer and/or shorter microtubules. These data lend credence to the supposition that aging is accompanied by perturbations of microtubule functions that ultimately are expressed as biomarkers characteristic of aging.

Aging↗
PubMed1992

Syphilis in the 'unbooked' pregnant woman.

To determine the prevalence of syphilis in the 'unbooked' pregnant woman attending King Edward VIII Hospital, Durban, mothers who had no previous history or record of antenatal care were studied over a 3-month period. One hundred and fourteen mothers were recruited, 35 (30.7%) of whom had reactive syphilis serology. None had clinical evidence of primary or secondary syphilis. Clinical evidence of congenital syphilis was found in 4 of the 35 (11.5%) babies born to mothers with reactive syphilis serology. While the fluorescent treponemal antibody absorption (FTA-ABS) IgG test was positive in umbilical cord and neonatal venous blood of all 35 babies, the FTA-ABS IgM test was negative in all specimens, including the sera from the 4 babies with clinical signs of syphilis. The FTA-ABS IgM test is therefore of little value for the laboratory confirmation of congenital syphilis. It also has limitations when it comes to screening asymptomatic neonates born to mothers with reactive syphilis serology.

Adult↗
PubMed1992

Silent ischemia in rehabilitation patients: limited clinical utility of electrocardiographic monitoring.

In a prospective blinded trial, 24-hour continuous electrocardiographic monitoring for silent ischemia was used to try to identify rehabilitation patients at risk for cardiac complications. Five of 42 patients had episodes of silent ischemia, none of which occurred during physical therapy sessions. One of these patients had syncope while wearing the Holter; none of the other four patients had significant cardiac complications during their rehabilitation, and all were discharged home. None of the patients without ischemia on the monitor had complications, but two patients of 14 whose ECGs precluded monitoring for ischemia had complications. In addition, six patients had episodes of nonsustained asymptomatic ventricular tachycardia, 12 had episodes of supraventricular tachycardia, and four had significant ventricular ectopy, all without clinical significance. Despite the apparent high sensitivity and specificity of the technique, the positive predictive value of monitoring eligible patients for silent ischemia was 20%. We conclude that ambulatory electrocardiographic monitoring for silent ischemia or ectopy has limited clinical utility in the rehabilitation population.

Aged↗
PubMed1991

The effect of changes in gramicidin conformation on bilayer lipid properties.

The effects of two different gramicidin conformations on lipid phase behaviour and dynamics are compared. Samples of chain-perdeuterated dimyristoylphosphatidylcholine containing gramicidin were first prepared with gramicidin in a state having a circular dichroism spectrum generally identified as corresponding to the non-channel conformation. The effects, on bilayer lipid properties, of gramicidin in this conformation were then determined using deuterium nuclear magnetic resonance measurements of acyl chain orientational order and transverse relaxation times as a function of temperature. These samples were then incubated at 65 degrees C to convert the gramicidin to a state with a circular dichroism spectrum of the type generally identified with the channel conformation. The nuclear magnetic resonance measurements were then repeated. In the gel phase, it was found that transverse relaxation time and chain orientational order of the lipid were insensitive to gramicidin conformation. In the liquid crystalline phase, gramicidin in the channel conformation was found to have a slightly larger effect on transverse relaxation and orientational order than gramicidin in the non-channel conformation. The perturbation of the phase behavior by gramicidin was found to be relatively insensitive to gramicidin conformation.

Circular Dichroism↗
PubMed1991

Effects of acute and chronic ethanol treatment on pre- and postsynaptic responses to baclofen in rat hippocampus.

Interactions between the GABAB receptor and acute or chronic ethanol treatment were studied using extracellular and intracellular electrophysiological recording techniques. Bath application of the GABAB receptor agonist, (-)-baclofen (0.1-100 microM) induced concentration-dependent inhibition of extracellularly recorded dendritic excitatory postsynaptic potentials (EPSPs) in the CA1 region of hippocampal slices. Responses to baclofen were unchanged relative to control either by simultaneous application of ethanol (10-60 mM) or by previous chronic ethanol exposure. The membrane potential of CA1 pyramidal neurons was reversibly hyperpolarized an average of 5 mV by pressure ejection of baclofen (1 mM). Bath application of ethanol (30 mM) alone occasionally caused a small depolarization of resting membrane potentials in CA1 neurons but failed to increase hyperpolarizing responses to pressure-ejected baclofen. However, in slices from chronic ethanol-treated animals hyperpolarizing responses to bath-applied baclofen (10 microM) were reduced by approximately 30% relative to controls. These results suggest that GABAB-mediated responses in CA1 hippocampal pyramidal neurons are relatively resistant to the acute effects of ethanol, but that continuous exposure to ethanol sufficient to induce physical dependence may evoke an adaptive reduction in some GABAB receptor mediated responses.

Animals↗
PubMed1991

An assessment of selective surveillance methods for detecting hospital-acquired infection.

Three selective surveillance methods were compared to a reference method in their ability to detect hospital-acquired infection (HAI) in patients occupying 122 beds of a district general hospital. The time for data collection was also assessed. The selective methods consisted of: (a) ward liaison surveillance (WLS), conferring with nursing staff twice weekly to determine patients with infections; (b) risk factor surveillance (RFS), the follow-up of patients with "clues" that indicated a risk of infection; and (c) laboratory-based ward liaison surveillance (LBWLS), the follow-up of positive microbiology reports by reviewing case records, in addition to conferring with nursing staff. The reference method consisted of total continuous clinical surveillance and the review of laboratory reports. During the 11-month period of the study, the reference method identified 306 HAI in 3,326 patients. LBWLS identified 71%, WLS 58%, and RFS 49% of HAI. The time for data collection (per week) was 7.75 hours for LBWLS, 4.3 hours for WLS, and 7.9 for RFS. In the United Kingdom, LBWLS was concluded to be an effective method of surveillance.

Cross Infection↗
PubMed1991

The interleukin-8 receptor is encoded by a neutrophil-specific cDNA clone, F3R.

Interleukin-8 (IL-8) is one of the most potent chemotactic agents for neutrophils and has been implicated as a major mediator of inflammation. The IL-8 receptor is expressed exclusively in neutrophils and belongs to the family of G-protein-coupled receptors. In a recent paper we reported the characterization of a cDNA clone, F3R, isolated from a neutrophil cDNA library and showed that it encodes a G-protein-coupled receptor which is exclusively expressed in neutrophils. We also suggested, based on expression studies in Xenopus oocytes, that the F3R protein product is an isoform of the (fMLP) receptor (Thomas, K. M., Pyun, H. Y., and Navarro, J. (1990) J. Biol. Chem. 265, 20061-20064). In this work, the F3R receptor cDNA is expressed in monkey kidney cells (COS-7) and is shown to encode the IL-8 receptor. F3R cDNA does not encode for a fMLP receptor isoform. We show conclusively that the F3R-transfected COS-7 cells express the IL-8 receptor at a density equivalent to that observed in neutrophils. The pharmacological profile of the F3R-transfected cells is the same as that of neutrophils. The apparent Kd values for binding of 125I-IL-8 to neutrophils and F3R-transfected COS-7 cell membranes were 1.2 and 1.4 nM, respectively. Antipeptide antibodies against a partial sequence of the F3R protein product specifically immunoprecipitate the IL-8 receptor from transfected cells as well as neutrophils. The molecular characterization of the IL-8 receptor should provide the basis for further studies on the identification of the binding domain of this inflammatory receptor.

Animals↗
PubMed1991

Evolution of neuropathy and myopathy during intensive vincristine/corticosteroid chemotherapy for non-Hodgkin's lymphoma.

Neuropathy and myopathy are common sequelae of intensive chemotherapy protocols that contain vincristine and corticosteroids. The authors prospectively monitored the evolution of neuropathy and myopathy during an intensive 12-week chemotherapy program for patients with intermediate and high-grade non-Hodgkin's lymphoma. In this study, vincristine was administered by bolus injection followed by a 3-day continuous intravenous (IV) infusion (total dose of 2.0 mg/m2 every other week); the maximum dose of vincristine was not arbitrarily limited. Cronassial, a mixture of four naturally occurring gangliosides, was administered in a randomized double-blind test to evaluate whether this agent could prevent vincristine-induced neuropathy. High doses of dexamethasone (50 mg/d for 3 days weekly or every other week) were also prescribed. Patients were monitored every 4 weeks with comprehensive physical and neurologic examinations and electrophysiologic studies of peripheral nerve function. Twenty-seven patients were fully evaluable. Weakness was a prominent adverse reaction in this study, and all patients had moderate to severe signs and symptoms of neuropathy and myopathy. Cronassial (100 mg) administered by intramuscular (IM) injection daily provided no protection against the development of neuropathic symptoms. Vincristine typically impaired fine-motor coordination initially, whereas corticosteroids were associated with delayed development of proximal muscle weakness. Results of electrodiagnostic studies did not add to the clinical examination results. The authors conclude that symptomatic weakness due to neuropathy or myopathy appears in a predictable manner during intensive vincristine/corticosteroid-based treatment protocols. Simple clinical tests can be used to rapidly distinguish between toxic effects due either to vincristine or corticosteroids, and routine implementation of these tests can prevent inappropriate dose attenuation of these agents.

Adult↗
PubMed1991

Tumor suppression by chromosome 11 is not due to cellular senescence.

Previous hybrid studies involving fusion of normal with immortal human cells indicated that the phenotype of cellular senescence is dominant and that immortality results from recessive changes in normal growth regulatory genes. We have further assigned 28 different immortal human cell lines to at least four complementation groups for indefinite division. In order to identify the chromosomes involved in regulating cell proliferation, we have introduced single human chromosomes by microcell fusion into immortal human cells representative of the different complementation groups. Our results demonstrate that the introduction of chromosome 11, implicated in tumor suppression, does not cause cellular senescence in three different immortal human cell lines tested.

Animals↗