Search PubMed⌕ Search

Biomedical subjects

R Freeman

Publications and source records attributed to R Freeman.

At least 19 recordsLinked to original sources
PubMed1999

The treatment of neurogenic orthostatic hypotension with 3,4-DL-threo-dihydroxyphenylserine: a randomized, placebo-controlled, crossover trial.

OBJECTIVE: To study the therapeutic effect and mechanism of action of 3,4-DL-threodihydroxyphenylserine (DL-DOPS) in neurogenic orthostatic hypotension. METHODS: The blood pressure (BP) response to an orthostatic challenge on DL-DOPS was compared with that of placebo in a randomized, double-blind, placebo-controlled, crossover trial in 10 patients. The mechanism of action of DOPS was studied by measuring forearm vascular resistance and changes in supine and upright plasma DL-DOPS and norepinephrine levels. The effect of DL-DOPS on the quality of life was determined by questionnaire. RESULTS: DL-DOPS increased the supine (p<0.001) and upright (p<0.05) systolic blood pressure (SBP) and diastolic blood pressure (DBP) (both p<0.01). The peak SBP on DL-DOPS in the supine position occurred 300 minutes after ingestion of the medication. The increase in BP was accompanied by an increase in plasma levels of norepinephrine and DL-DOPS in both the supine and upright positions after DL-DOPS ingestion (p<0.0001). There was a trend toward improvement in symptoms of orthostatic intolerance. CONCLUSION: DL-DOPS improved features of neurogenic orthostatic hypotension in patients with central and peripheral autonomic nervous system disease. There was an increase in plasma norepinephrine. No major side effects occurred.

Adult↗
PubMed1999

Granular cell tumor with cirrhosis and transplantation.

Granular cell tumor is a rare cause of hepatic dysfunction. We report here on a patient who underwent liver transplantation for this ailment. In our literature review, the common bile duct was most commonly involved (56%). A wide variety of therapies were advanced for this type of lesion, spanning three decades of care. Twenty-eight patients (49%) had no follow-up reported, and another 2 (3%) were found at autopsy. Sixteen patients (28%) were followed more than 1 year, with 72% followed less than 1 year if at all. We present the first case of a granular cell tumor being treated with liver transplantation. Although adequate early excisional surgery should obviate the need for transplantation in these cases, widely disparate therapy and poor follow-up may mask generally inadequate therapy for this lesion. The authors recommend thorough excision and long-term follow-up for patients with this entity to avoid secondary biliary cirrhosis and to eliminate the preventable need for transplantation.

Adult↗
PubMed1999

The case for mother in the surgery.

The argument for and against the presence of the mother in the surgery while her child undergoes a dental procedure has been contentious. Using a psychodynamic framework, this paper suggests that the mother's presence is necessary for the dentist-child relationship to function correctly.

Anxiety, Separation↗
PubMed1999

The role of the dental nurse in general practice.

Dental nurses have reported dissatisfaction with their work which is associated with feelings of lack of control and being undervalued. This paper examines some of the possible reasons behind job dissatisfaction with illustrations from a pilot study conducted in general dental practice.

Attitude of Health Personnel↗
PubMed1999

Atypical anorexia nervosa: separation from typical cases in course and outcome in a long-term prospective study.

OBJECTIVE: To assess differences in long-term course and outcome between typical and atypical cases of anorexia nervosa. METHOD: A naturalistic, longitudinal prospective design was used to assess recovery, relapse, and onset of binge eating over 10 to 15 years in patients ascertained through a university-based specialty treatment program. Atypical anorexia nervosa was distinguished from the diagnostically prototypic form of the disorder based on the continuous absence of morbid fear of weight gain and body size distortion during the inpatient phase of treatment. Patients were assessed semiannually for 5 years then annually thereafter until the final visit. RESULTS: Compared to pure cases of anorexia nervosa, atypical cases were less likely to drop weight after discharge, recovered more rapidly, and had lower cumulative risk for developing binge eating. CONCLUSION: It has been argued recently that weight phobia and body image disturbance should not be viewed as critical to the diagnosis of anorexia nervosa. This study shows that the absence of these particular symptoms in patients presenting with malnutrition secondary to extreme dietary restriction predicts a less malignant course and outcome compared to typical cases of anorexia nervosa. These course differences suggest that the division of patients into typical versus atypical diagnostic subtypes may be nosologically valid and clinically useful.

Adult↗
PubMed1999

Suppression of radiation damping in high-resolution NMR.

The radiation damping field induced by an intense NMR line can be counterbalanced by a DANTE sequence of small flip angle pulses of opposite phase applied during the free induction decay. The transient NMR signal is acquired, one complex data point at a time, in the intervals between these DANTE pulses. As the intense signal decays, reducing the radiation damping field, the flip angles of the DANTE pulses are reduced at a matching rate. An experimental test on an aqueous solution of d-glucose demonstrates a reduction in linewidth at half height from 13.5 to 0.8 Hz, revealing a weak doublet response previously hidden under the broad water line.

Glucose↗
PubMed1999

Reduced intrapatient variability of cyclosporine pharmacokinetics in renal transplant recipients switched from oral Sandimmune to Neoral.

Sixty-six renal transplant patients maintained on Sandimmune, the traditional formulation of cyclosporine, participated in an open-label, sequential trial to compare intrapatient variability in drug exposure before and after a switch to Neoral. Three 12-hour cyclosporine pharmacokinetic profiles were obtained over approximately 6 weeks while patients were receiving Sandimmune. Patients were then switched to Neoral, with the dose adjusted as necessary to maintain target trough blood cyclosporine concentrations. At approximately 4 and 6 weeks postconversion, 2 additional pharmacokinetic profiles were obtained. Key pharmacokinetic variables analyzed were area under the concentration-time curve (AUC), maximum concentration (Cmax), and predose trough concentration (C0). Intrapatient variability in drug exposure for dose-normalized mean AUC, Cmax, and C0 was significantly reduced with Neoral, with 50 (76%), 57 (86%), and 45 (68%) patients experiencing reduced variability in AUC, Cmax, and C0, respectively (P < 0.001). Additionally, the total exposure to cyclosporine was more predictable from the trough level of cyclosporine with Neoral; the relationship between AUC and C0 was 0.81 for Neoral at both pharmacokinetic profiling time points but ranged from 0.49 to 0.69 for the 3 Sandimmune time points. The large reductions in intrapatient variability of pharmacokinetic variables for cyclosporine provided by Neoral indicate an improvement in the consistency of drug exposure, which may translate into important clinical benefits.

Adult↗
PubMed1999

Pyrolysis mass spectrometry analysis of free-living and symbiotic cyanobacteria.

The potential of pyrolysis mass spectrometry to distinguish closely related cyanobacterial strains was assessed by using the technique to compare symbiotic cyanobacteria isolated from the hornwort Phaeoceros laevis and free-living cyanobacterial strains at the same field site. The same strains had previously been compared using polymerase chain reaction-based DNA fingerprinting techniques (West & Adams 1997, Appl. Environ. Microbiol. 63: 4479-4484). Many of the strains were grouped identically by the two techniques, although there were some differences, possibly resulting from the ability of these cyanobacteria to develop a range of specialised cell types having different chemical compositions to the vegetative cells. Although growth conditions were chosen to suppress cellular differentiation, this may not always have been completely successful. With careful control of growth conditions pyrolysis mass spectrometry has considerable potential as an additional tool for the phenetic comparison of cyanobacterial strains. It has the advantage that analysis is directly derived from whole cells, and hence is simpler and cheaper than DNA-based methods, although it does require the growth of axenic strains. The technique may be particularly useful in the study of some of the more cryptic unicellular and non-heterocystous filamentous cyanobacterial groups, in which the lack of cellular differentiation should minimise any variability in the chemical composition of cells.

Bacterial Typing Techniques↗