Search PubMed⌕ Search

Biomedical subjects

M Rosen

Publications and source records attributed to M Rosen.

At least 145 records · Page 8Linked to original sources
PubMed1989

The effect of latex gloves on setting time of vinyl polysiloxane putty impression material.

Vinyl polysiloxane putty impression material (VPPIM) setting is unreliable when mixed in gloved hands. The exact reason for this remains obscure. This report focuses on the effect of natural and synthetic latex gloves on the setting of VPPIMs. This report indicates that synthetic latex gloves (SLG) have no effect on setting reaction of VPPIMs. However, natural latex gloves (NLG) significantly delay the setting reaction (P less than 0.05). Manufacturers should take note of this and supply SLGs for mixing. Dentists contemplating the use of VPPIMs should take these findings into consideration.

Chemical Phenomena↗
PubMed1989

Management of anxiety in dental practice in the UK.

A postal questionnaire was sent to a random sample of dentists in the United Kingdom. The response rate was 59.9%. Anxiety was reported as a significant problem by 66% of dentists and information was gained regarding the techniques used to manage this anxiety. 'Patient management' and general anaesthesia were the techniques most commonly employed. The frequency of usage of intravenous and inhalational sedation varied according to the age of the patient. Only 55.3% of dentists in general practice had any training in a sedative technique.

Anesthesia, Dental↗
PubMed1989

Comparison of diazepam with midazolam as i.v. sedation for outpatient gastroscopy.

We studied 26 patients in a double-blind investigation to compare psychomotor and cognitive recovery for 30 h after sedation for day-case gastroscopy with i.v. diazepam 0.15 mg kg-1 or midazolam 0.07 mg kg-1. Significantly more patients reported side effects at 7, 10 and 30 h post-gastroscopy after diazepam than after midazolam (P less than 0.05). Compared with baseline, the midazolam group was significantly impaired in critical flicker fusion threshold, reaction time, dexterity and visualization tasks up to 4 h after administration (P less than 0.05). There was a significant association between midazolam and amnesia for the procedure (P less than 0.001).

Adult↗
PubMed1989

Intravenous enalaprilat and autonomic reflexes. The effects of enalaprilat on the cardiovascular responses to postural changes and tracheal intubation.

Thirty healthy patients, who were to undergo surgery which required tracheal intubation, were given an intravenous injection of enalaprilat (either 0.5 mg, 1 mg, 2 mg or 4 mg; six patients for each dose) or normal saline 17 minutes before induction of anaesthesia with thiopentone 3-5 mg/kg, and suxamethonium 1.5 mg/kg. Postural manoeuvres were performed 5 minutes before and 6, 11 and 16 minutes after enalaprilat or saline. Complete inhibition of angiotensin converting enzyme occurred with all doses of enalaprilat, which allowed the four different treatment groups to be considered as one large treated group. The mean arterial pressure was almost unchanged during the postural manoeuvres; the heart rate increased, mostly similarly (by approximately 10%) in both groups. Mean arterial pressure in the recumbent position decreased over the 17 minutes before induction in the enalaprilat group, and increased slightly in the control group (treated mean, -5.0%; controls mean, 1.8%; difference, -6.8%; 95% confidence intervals of difference, -2.3 to -11.3%, p less than 0.01). This difference was again seen after induction (treated, -8.0%; controls, 7.7%; confidence intervals of difference, -0.6 to -31%) and for a 5-minute period shortly after tracheal intubation. The increases in mean arterial pressure produced by intubation itself were similar in both groups (treated, + 36%; controls, + 35%; 95% confidence intervals of difference, -16% to + 18%). Changes in heart rate after induction were also similar in both groups. It is concluded that intravenous enalaprilat acted as a hypotensive agent with a sparing effect on autonomic reflexes, both before and after induction of anaesthesia.

Adult↗
PubMed1989

Epidural versus general anaesthesia for elective caesarean section. Effect on Apgar score and acid-base status of the newborn.

Elective Caesarean section deliveries over a 5-year period were studied to compare the effect of epidural block with general anaesthesia on the condition of the infant at birth. The Apgar score and umbilical arterial acid-base status were used as determinants of the latter. Epidural block was used in 139 (22.8%) mothers while 471 (77.2%) were performed under general anaesthesia. No babies in the epidural group were severely depressed (Apgar less than 4), compared with 6.2% in the general anaesthesia group. Only 4.3% of the epidural sections were moderately depressed (Apgar 4-6), compared with 15.4% of the others. These differences remained highly significant when infants of less than 2500 g were excluded, and when matched groups were compared. Mean umbilical arterial pH was similar within the two groups (pH 7.28), and was not consistent with asphyxia in almost 90% of the depressed infants. The findings suggest that general anaesthesia, rather than asphyxia or aortocaval compression, is responsible for most of the depressed infants born by elective Caesarean section. This may involve over 20% of babies delivered in this manner, so greater use of epidural block for elective Caesarean section is recommended. Further investigations are required to improve results with general anaesthesia.

Acid-Base Equilibrium↗
PubMed1989

Propofol-induced anaesthesia. Double-blind comparison of recovery after anaesthesia induced by propofol or thiopentone.

Postoperative psychomotor and cognitive recovery were assessed after anaesthesia induced by either propofol or thiopentone, and maintained with nitrous oxide and halothane in 40 unpremedicated dental patients. Performance was shown to be impaired one hour postoperatively for the whole sample in hand-eye coordination (p less than 0.001), reaction time (p less than 0.001) and digit span (p less than 0.05). There was evidence of impairment at 3 hours postoperatively in reaction time (p less than 0.05) and ataxia (p less than 0.01). Performance also deteriorated in the dexterity and aiming tasks. Patients reported significantly less clumsiness by 24 hours in blurred vision and shivering (p less than 0.05) and by 48 hours less coughing (p less than 0.05). However, there was no significant difference between groups. No evidence showed that recovery in the propofol group was faster, so it was concluded that induction with propofol offered no advantage when anaesthesia is maintained with nitrous oxide and halothane for the periods of time reported in this study.

Adolescent↗
PubMed1989

Flecainide and cardiac dysrhythmias during dental extraction under anaesthesia.

In a randomized double-blind study, either oral flecainide acetate 400 mg (a Class IC anti-dysrhythmic drug) or placebo was given in two divided doses 12 and 2 h pre-operatively to 38 patients undergoing outpatient molar extractions under halothane anaesthesia. The ECG was continuously monitored from the patients' arrival at the out-patient theatre until discharge, using a two-channel ambulatory magnetic tape recorder. There was a much lower incidence of ventricular dysrhythmias in patients who received flecainide (22%) than those who received placebo (75%) (P less than 0.05). In addition, dysrhythmias were both more severe and more prolonged in the untreated group, prompting treatment with intravenous practolol in seven patients (35%). Flecainide was well tolerated and no adverse effects were reported.

Adolescent↗
PubMed1989

The effect of maize starch on setting time of vinyl polysiloxane putty impression materials.

Maize starch is widely used as a glove lubricant, and the belief is commonly held that it is responsible for retarding the setting reaction of vinyl polysiloxane putty impression material (VPPIM). In contrast, our research demonstrated experimentally that maize starch glove lubricant (MSGL) did not inhibit but significantly (P less than 0.05) accelerated the setting reaction of VPPIM.

Dental Impression Materials↗
PubMed1989

Glass ionomers and discoloration: a comparative study of the effects of tea and coffee on three brands of glass ionomer dental cement.

This study was undertaken to compare the in vitro discoloration of 3 brands of glass ionomer dental cement, Chemfil, Fuji Type II, and Ketac-Fil. Forty-eight specimens of each brand were prepared. Sixteen specimens of each brand were placed in tea, coffee and, as a control, water. Discoloration was evaluated by means of reflection spectrophotometry at 2, 4, 8, and 16 wk. Analysis of the data indicated that most discoloration occurred during the first 2 wk of immersion in the staining media and a little further discoloration took place between 2 and 16 wk (p less than 0.05). Tea discoloured glass ionomer more than did coffee (p less than 0.05) and Fuji Type II discoloured the most, Ketac-Fil the least whilst the discoloration of Chemfil lay between these two (p less than 0.05).

Coffee↗
PubMed1989

Oral controlled-release morphine and gut function: a study in volunteers.

The effects of a single 30-mg tablet of oral controlled-release (OCR) morphine (MST) on gastric emptying and small-intestine transit time (SITT) were compared with placebo in a double-blind, cross-over trial, on ten healthy volunteers. Gastric emptying was measured by paracetamol absorption and SITT by the rise in breath hydrogen after a carbohydrate test meal. There was no alteration in the absorption of paracetamol given 90 min after OCR administration but this was well before peak plasma morphine levels occurred. However, 30% of subjects had nausea after OCR morphine. Mean SITT in controls was 300 min (range 120-460 min) which was significantly prolonged in eight of the 10 subjects (P less than 0.05) and beyond the study period of 480 min in six subjects. Further study is required to determine how this compares with intramuscular morphine. Peak blood levels of morphine occurred at 3 h with a mean plasma concentration of 12.3 micrograms l-1 (SEM 2.0 micrograms l-1).

Administration, Oral↗
PubMed1989

Comparison of CT, MR, and PET in Alzheimer's dementia and normal aging.

We compared the findings of computed tomography (CT), magnetic resonance (MR), and positron emission tomography (PET) scans of glucose metabolism in 30 patients with clinically diagnosed Alzheimer's Disease (DAT) to those noted in 25 age-matched normal controls. Mean ratings of cortical and ventricular atrophy on CT and of metabolic abnormality on PET were significantly different (p less than 0.001 and p less than 0.0001, respectively) between two subject groups, however, there was a considerable overlap in reading of cortical atrophy. CT hypodensities were present in 17% of DAT patients and 12% of controls. MR revealed numerous additional periventricular and deep white matter signal changes. Neither hypodensities nor hyperintensities were correlated with PET abnormalities. Although, not infrequently, hypometabolic areas on PET scans corresponded to atrophic regions on anatomic images, they also occurred without such changes. Interestingly, cortical high signal intensity seen on MRI was frequently observed to be associated with areas of hypometabolism. Our results suggest that PET may be the most sensitive modality for detecting cortical involvement in DAT.

Aged↗
PubMed1988

The interaction of platinum and anthrapyrazole antitumor drugs with mouse thymocytes studied by terbium fluorescence.

The fluorescent lanthanide, terbium has been employed to study the effect of a series of platinum and anthracycline drugs and an anthrapyrazole (oxanthrazole) on terbium binding to mouse thymocytes. It was observed that terbium fluorescence intensity was markedly decreased by two platinum drugs (cis-dichlorodiammine platinum(II) (cis-DDP) and cis-dichloro-trans-dihydroxybis(isopropylammine) platinum(IV) (CHIP)) and an anthrapyrazole (oxanthrazole), but that the lipophylic derivative cis-diammine-1,1-cyclobutanedicarboxylate platinum(II) had a small but significant effect and the anthracyclines (at low concentrations) had no effect. The calcium channel blocker, verapamil also had no effect. The effect of cis-DDP was markedly dependent on ionic strength in contradistinction to CHIP. The decreases in phosphorescence decay produced by cis-DDP also showed a marked dependence on ionic strength. It is proposed that cis-DDP interacts with the membrane primarily by a charge effect, but that CHIP may produce a conformational change in the membrane. These data are interesting, since the lipophylic platinum drugs (CHIP and CBDCA) also increased significantly the amount of bound intracellular calcium, but all the drugs decreased mitogen-stimulated calcium uptake into mouse thymocytes.

Animals↗
PubMed1988

Feasibility of self-administration analgesia by the intramuscular route in labour.

The feasibility of patient-controlled on-demand analgesia by the intramuscular route during labour was tested on 10 primigravid mothers. Pethidine 50 mg or meptazinol 75 mg was available double-blind at minimum intervals of 20 min. The mean dose demanded was 190 (SD 96.2) mg of pethidine and 285 (SD 97.8) mg of meptazinol. The dose of pethidine is similar to that demanded by the intravenous route. Pain evaluations were not significantly different, but one mother who had meptazinol opted for epidural analgesia, and 2 wished they had done so. The system could be easily managed by all the mothers and there were not technical difficulties. Self-administered intramuscular analgesia could be instituted by a midwife with a dosage scheme similar to current practice. A field trial by midwives of self-administered intramuscular analgesia with pethidine is indicated.

Adult↗