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Biomedical subjects

B Taylor

Publications and source records attributed to B Taylor.

At least 19 recordsLinked to original sources
PubMed1995

A standardized patient program in a mandatory geriatrics clerkship for medical students.

This article describes the development and implementation of a new standardized patient program in a required geriatrics clinical clerkship for fourth-year medical students. A student survey was also conducted to provide evaluations of the program and to determine the frequency with which students' clinical skills are directly evaluated by faculty. Thirty-six percent reported never having been observed while obtaining a history and 24% having been observed only once; 26% had never been observed while completing a physical examination and 39% had been observed only once. The implementation of a standardized patient program provided students with direct feedback on their clinical skills and was rated positively, (good, very good, or outstanding) by 76% of the students.

Clinical Clerkship↗
PubMed1995

Performance characteristics for the quantitation of plasma HIV-1 RNA using branched DNA signal amplification technology.

Highly sensitive assays that quantitate human immunodeficiency virus type 1 (HIV-1) RNA may be valuable for clinical research and the treatment of HIV-1-infected patients. In this study we evaluated the reproducibility and accuracy of the first-generation branched DNA (bDNA-1.0) signal amplification assay under conditions that are relevant to routine use in a clinical context. We show that the bDNA-1.0 assay was able to discern two- to three-fold changes in plasma HIV-1 RNA levels as significant. Reverse transcription coupled to polymerase chain reaction (RT-PCR) was less reproducible and required a 3.7- to 5.8-fold change in plasma HIV-1 RNA levels to be statistically significant. The accuracy of the bDNA-1.0 assay in RNA quantitation was not affected by HIV-1 genotypic variation or by the presence of hemoglobin, bilirubin, lipemia, or any of a dozen therapeutic drugs. Using the bDNA-1.0 assay, we show that HIV-1 RNA levels in plasma specimens were stable when stored at -80 degrees C and were able to withstand at least three freeze-thaw cycles without significant loss. We also examined the performance of an ultrasensitive bDNA assay with improvements to the signal amplification technology. The ultrasensitive bDNA assay displayed a quantitation limit of approximately 500 RNA Eq/ml, yet maintained a dynamic quantitation range up to 1.6 x 10(6) RNA Eq/ml. Like the bDNA-1.0 assay, the ultrasensitive bDNA assay was not affected by HIV-1 genotype variability.

Anticoagulants↗
PubMed1995

Clinical evaluation of the Franklin Applied Physics Cosmetic Cover for lower limb prostheses: a preliminary report.

The Franklin Applied Physics (FAP) Cosmetic Cover is the result of research and development directed by Dr. Robert Erb at the Franklin Research Center, Norristown, PA. The FAP Cover is a silicone rubber cosmesis designed to improve the appearance of lower limb prostheses and provide wider social integration for the wearer. The Technology Transfer Section, Rehabilitation Research and Development Service, Department of Veterans Affairs, coordinated a pilot study of four pre-commercial covers at selected sites. Participating prosthetists and subjects evaluated fit, relevant physical criteria, and overall potential value of the cover. The following statements summarize responses of the participants: 1) well accepted with regard to overall fit, appearance, and ease of donning/doffing; 2) lightweight, highly elastic, and easy to maintain; and 3) split toe and closed toe versions are needed for above-knee and below-knee models. Data gleaned from the pilot study were used to define dimensions for standardized off-the-shelf sizing and to make recommended modifications, resulting in pre-market models that are ready for a national field evaluation.

Artificial Limbs↗
PubMed1995

The surgical anatomy of the deep femoral artery.

Lower extremity ischemia is a common disorder that in the majority of cases is associated with occlusion of the superficial femoral artery. The deep femoral artery is recognized as an important collateral pathway to the genicular arterial system, thus accounting for the appearance of symptoms only after its involvement in the disease process. Surgical exposure of the deep femoral artery is often necessary in vascular reconstructive procedures. Furthermore, because it supplies the bulk of the thigh musculature, plastic surgeons have shown great interest in the muscular branches of the deep femoral artery when designing procedures that incorporate myocutaneous flaps. This article gives a detailed account of the embryology, anatomical relations, important variations, and branches of the deep femoral artery. Recommendations for the surgical exposure of this artery at different levels are also presented.

Femoral Artery↗
PubMed1994

C1q binding properties of monomer and polymer forms of mouse IgM mu-chain variants. Pro544Gly and Pro434Ala.

The effect of replacing proline with alanine at position 434 in the C mu 3 domain (P434A) and with glycine at position 544 in the C mu 4 domain (P544G) of the mu-chain of mouse IgM has been studied. The P434A substitution results in the loss of measurable complement-mediated cytolytic activity (CML) and a decrease in the association rate constant at low ionic strength (mu = 0.06), that results in a diminished Ka for C1q binding to P434A IgM bound to haptenated cells (0.4 x 10(9) M-1). Binding of C1(qr2s2) could not be detected. In contrast, replacement of proline at 544 had no measurable effect on the cytolytic or C1q/C1 binding properties of the polymeric molecule, supporting the view that the C mu 3 domain is important in C1q binding and CML. The secreted monomeric subunit of P544G was not able to mediate CML. Also, whereas hapten-bound P544G polymer bound C1q with a functional affinity of 1.5 x 10(9) M-1 at low ionic strength (mu = 0.06), similar to that observed with wild-type polymer (1.7 x 10(9) M-1) and wild-type IgG monomer (4.7 x 10(9) M-1), no C1q binding was detected with the P544G IgM monomer. This could not be attributed to differences in glycosylation. Inasmuch as the P544G mutation per se had no effect on the C1q binding properties of the polymer, we conclude that unlike IgG, aggregation does not sufficiently enhance the avidity of IgM monomer to enable it to activate complement. Augmentation of the site must occur during polymerization or when the IgM binds to Ag.

Animals↗
PubMed1994

Haloperidol-induced morphological changes in striatum are associated with glutamate synapses.

Sub-chronic treatment with the typical neuroleptic, haloperidol (0.5 mg/kg/d, s.c.), but not the atypical neuroleptic, clozapine (35 mg/kg/day, s.c.), causes an increase in synapses containing a perforated postsynaptic density (referred to as 'perforated' synapses) and in dopamine (DA) D2 receptors within the caudate nucleus [46]. To determine if these perforated synapses are glutamatergic, we systemically co-administered MK-801 (0.3 mg/kg/day for 2 weeks), a non-competitive antagonist at the N-methyl-D-aspartate (NMDA) receptor-associated ion channel, and haloperidol. MK-801 blocked the haloperidol-induced increase in striatal perforated synapses, but not the haloperidol-induced increase in DA D2 receptors. Injection of MK-801 into the striatum also attenuated the haloperidol-induced increase in perforated synapses. Post-embedding immuno-gold electron microscopy using antibodies to glutamate indicated that the gold particles were localized within striatal presynaptic nerve terminals that make contact with perforated postsynaptic densities. These findings support the hypothesis that the haloperidol-induced increase in perforated synapses is regulated by the NMDA subtype of excitatory glutamate receptor. The increase in perforated synapses following administration of haloperidol, which is associated with a high incidence of extrapyramidal side effects (EPS), and the lack of a synaptic change following administration of clozapine, known to have a low frequency of EPS, suggests that glutamate synapses play a role in the motoric side effects that are observed with typical neuroleptic drug treatment.

Animals↗
PubMed1994

Reliability and construct validity of a structured technical skills assessment form.

Current methods of evaluating technical competence of surgical residents are subjective and potentially unreliable. This study assesses the reliability and construct validity of a new format for the assessment of technical ability, the two part Structured Technical Skills Assessment Form (STSAF). Part I, which is completed while an operation is proceeding consists of approximately 120 essential components of the procedure. Part II, completed at the end of the operation, is a 10-point global rating form. Forty-one operations were evaluated using the STSAF, with multiple observers present at 26. Inter-rater reliability of both Parts I and II were high (.78 and .73, respectively). Statistically significant differences were noted between senior-resident and junior-resident performances, suggesting construct validity. The incorporation of structured guidelines to the assessment of technical skill leads to high inter-rater reliability and construct validity, which ultimately may result in improved and reproducible evaluations of surgical trainees.

Cholecystectomy↗
PubMed1994

Validating the GDS depression screen in the nursing home.

OBJECTIVE: The GDS (Geriatric Depression Scale) has demonstrated validity among ambulatory elderly but is less useful in nursing home (NH) populations, probably because of high rates of cognitive impairment. We, therefore, sought the lowest level of Mini-Mental Status Exam (MMSE) score for which the GDS would remain valid. DESIGN: Validation Study. SETTING: Nursing Homes in New York City. PARTICIPANTS: A total of 66 of 168 newly admitted residents to the NH were able to complete psychiatric assessment, undergo an MMSE, and complete the GDS. The psychiatrists and testers (all non-MDs) were blinded to each others' results. Using a cutoff of 10 or greater on the GDS to indicate depression, the GDS's validity (when compared with the psychiatric diagnoses) was sought at ever decreasing levels of cognitive function as measured by the MMSE. RESULTS: The results of all participants (n = 66) revealed a sensitivity of 63% and a specificity of 83%. When only those with an MMSE score > or = 15 (the best cutoff score) were included, 44 (64%) participants were selected, with a sensitivity and specificity of 84% and 91%, respectively. CONCLUSIONS: The two-step procedure of first selecting those with MMSE scores > or = 15 and then giving the GDS significantly increases the utility of the GDS in detecting depression in NH residents and should improve the diagnostic process for this widely underdetected problem.

Aged↗
PubMed1994

Reaction to injury following balloon angioplasty and intravascular stent placement in the canine femoral artery.

Intravascular stents are used clinically as an adjunct to coronary and iliac angioplasty. This study was performed to evaluate the thrombogenicity and intimal hyperplasia incited by stents deployed in non-injured and in balloon-injured femoral arteries in the canine model. Medinvent stents (4 mm) were placed in the femoral arteries bilaterally in five mongrel dogs via cut down. This was preceded by balloon catheter angioplasty of the stent site on one side. Platelet deposition was measured at 30, 60, and 90 minutes and at 24 and 48 hours after stent placement, using gamma camera imaging of Indium111 platelets. The animals were killed after 2 months using a pressure perfusion technique, and the stents harvested. All vessels were patent at the time of harvest. Neointimal thickness was measured by computer image analysis. Platelet deposition was significantly increased on the angioplastied side compared to the non-angioplastied side at 60 minutes (5.67 x 10(9) +/- 1.4 versus 2.17 x 10(9) +/- 0.5 platelets/cm; P < 0.05), at 90 minutes (8.13 x 10(9) +/- 1.8 versus 2.33 x 10(9) +/- 0.6 platelets/cm; P < 0.05), and at 24 hours (stent-to-blood ratio = 15.86 +/- 6.3 versus 3.75 +/- 1.5; P < 0.05). Neointimal thickness was also significantly greater on the side of combined angioplasty and stent placement (0.45 +/- 0.21 mm versus 0.33 +/- 0.09 mm; P < 0.05). These results demonstrate that placement of intravascular stents in normal arteries is associated with a certain degree of thrombogenicity and formation of neointimal hyperplasia. Combining balloon angioplasty with stent placement significantly augments both thrombogenicity and production of intimal hyperplasia.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon↗
PubMed1993

Factors affecting uptake of measles, mumps, and rubella immunisation.

OBJECTIVE: To study factors affecting uptake of measles, mumps, and rubella immunisation. DESIGN: Cohort study using data from computerised child health systems. SETTING: 10 health districts in North East Thames and North West Thames regions. SUBJECTS: 7841 children born in January to March 1990 and resident in the districts up till the end of October 1991. MAIN OUTCOME MEASURES: Overall uptake of measles, mumps, and rubella immunisation, variation of uptake among groups of children, and odds ratio of being vaccinated against measles, mumps, and rubella. RESULTS: The overall uptake rate of measles, mumps, and rubella immunisation for the study cohort in the 10 districts was 82%. Wide variation was identified among children with different demographic characteristics. Lower uptake was associated with absent or incomplete primary immunisation, including omission of pertussis vaccine. Other factors affecting uptake included the type of resident district, birth order, where registered for immunisation (general practitioner or clinic), and one parent family status. CONCLUSIONS: Many districts have difficulties in meeting the 90% target for measles, mumps, and rubella immunisation, mainly because of the characteristics of their local population. To increase overall coverage, the health service should target families with adverse factors, especially those whose children have missed previous immunisations.

Birth Order↗
PubMed1993

Extended-cycle elutriation to adjust T-cell content in HLA-disparate bone marrow transplantation.

We report the development of a double-cycle elutriation (DCE) technique separating 3 or greater logs of T cells from a stem-cell-enriched marrow fraction and the results of phase I T-cell depletion studies with HLA-disparate related bone marrow transplantation (BMT) donors in two patient groups. In group 1, 10 patients with refractory hematopoietic malignancies received combination chemotherapy, total body irradiation (TBI), and immunosuppression (pre- and post-BMT), and hematopoietic rescue with a marrow transplant, depleted of T cells by elutriation. Potentially to promote engraftment and a graft-versus-leukemia (GVL) effect, 0.5 to 0.75 x 10(5) T cells/kg were added back. All 10 patients engrafted. Five patients developed acute graft-versus-host disease (GVHD; four grade II, one grade III) and two subsequently developed chronic GVHD. Two patients have relapsed (median follow-up, 206 days; range, 46 to 1,035). Four patients died of BMT-related complications (three of infection, one of veno-occlusive disease [VOD]). Four patient are disease-free survivors (median follow-up, 960 days; range, 670 to 1,035). Group 2 included five infants, four with congenital lymphohematopoietic deficiencies and one with refractory acute lymphocytic leukemia (ALL). In these infants, busulfan and increased cyclophosphamide were substituted for TBI. Only the ALL patient received added T cells. Three patients engrafted: one has stable mixed chimerism, one relapsed with ALL, and one rejected the marrow. One patient had primary autologous recovery, while another failed to engraft. None developed GVHD. We conclude that, in this setting of HLA-disparate BMT with post-BMT antithymocyte globulin (ATG) and corticosteroids, DCE significantly depletes T cells from the marrow and that a defined number of T cells can be added without the occurrence of severe GVHD.

Adolescent↗