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A Smith

Publications and source records attributed to A Smith.

At least 1,171 records · Page 65Linked to original sources
PubMed1983

Assessment of oral-motor reflexes in stutterers and normal speakers: preliminary observations.

Reflex responses of nine stutterers and nine normal speakers to low-level tactile and auditory stimuli were measured as changes in isometric molar biting force and masseter muscle activity. Tactile stimuli (mechanical displacement of the tissue) were applied to five intraoral and perioral sites. The acoustic stimulus was noise gated on for 12 msec. These low-level stimuli significantly modulated jaw-closing force and muscle activity in most of the subjects tested. In general, the initial effect of both auditory and tactile stimuli was suppression, although the initial response was excitation in some subjects with some forms of tactile stimulation. Within both groups of subjects, the amplitude and direction of reflex responses, particularly to mechanical stimuli, were highly variable between subjects, but these measures were stable within an individual over repeated tests.

Adult↗
PubMed1983

Isolation of stable mouse cell lines that express cell surface and secreted forms of the vesicular stomatitis virus glycoprotein.

We have characterized two stable transformed mouse cell lines (CG1 and CTG1) that express either the normal vesicular stomatitis virus glycoprotein (G) or a truncated form of the G protein (TG) that lacks the COOH-terminal anchor sequences and is secreted from the cells. These cell lines were obtained using a hybrid vector consisting of the transforming DNA fragment of bovine papilloma virus linked to a segment of the SV40 expression vector pSV2 containing cloned cDNA encoding either the normal or truncated form of the vesicular stomatitis virus G protein. Using indirect immunofluorescence we have found that greater than 95% of the cells in each line express the G protein(s), although the level of expression within the population is variable. The normal G protein expressed in these cells obtains its complex oligosaccharides in less than 30 min and is transported to the cell surface. In contrast, the TG protein obtains its complex oligosaccharides with a half-time of about 2.5 h. Immunofluorescence data show an apparent concentration of the TG protein in the rough endoplasmic reticulum. These data together suggest that transfer of this anchorless protein from the rough endoplasmic reticulum to the Golgi apparatus is the rate-limiting step in its secretion. We observed, in addition to normal G protein, two smaller G-related proteins produced in the CG1 cell line. We suggest that these proteins could result from aberrant splicing from sites within the G mRNA sequence to the downstream acceptor in the pSV2 vector.

Amino Acid Sequence↗
PubMed1983

Liver disease in haemophiliacs: an overstated problem?

Successful percutaneous liver biopsy was carried out on 12 multi-transfused haemophiliacs from the Manchester area with persistently abnormal liver function tests. Only one patient showed evidence of chronic active hepatitis with progression to active micronodular cirrhosis although a further four patients showed some evidence of mild chronic active hepatitis. This represents a much lower incidence of severe histological liver damage than many previous reports and implies that liver biopsy in asymptomatic haemophiliacs may not be indicated as a routine procedure, particularly in the absence of proven therapy. Dynamic liver function tests may prove to be a useful indicator of deteriorating liver function in the otherwise asymptomatic haemophiliac.

Adolescent↗
PubMed1983

Chromosome aneuploidy in Alzheimer's disease.

We present cytogenetic findings in 9 patients with Alzheimer's disease (AD) and 35 normal age matched controls. The study was undertaken due to reports of increased aneuploidy in individuals with AD. Coded peripheral blood chromosome preparations were evaluated for aneuploidy; there were 4.5% hypomodal cells in AD patients compared with 5.5% in controls. There were no hypermodal cells in the AD group and only 0.7% among the controls. Statistical analyses of the results did not show any differences between AD patients and controls in these data. There was a statistically significant increase in the loss of C group chromosomes in the old controls which we attribute to ageing.

Aged↗
PubMed1983

Urethral ectopic ureter with a ureteric valve.

An unusual case of a urethral ectopic ureter in a girl is reported. Only the upper half of the ureter was a megaloureter, the distal half being stenosed. The appearances were consistent with the presence of a ureteric valve.

Child, Preschool↗
PubMed1983

Studies on the prevalence and epidemiology of urinary stone disease in men in Leeds.

A postal survey among 2% of men in Leeds showed that the prevalence of urinary stone disease is 3.8%. The prevalence of upper urinary tract and spontaneously passed stones increases progressively from 0.7% in social class 5 to 5.0% in social class 1 but that of bladder stones (0.7% in the group as a whole) is independent of social class. There is an initial peak of upper urinary tract and spontaneously passed stones commencing at age 20 and having a projected prevalence at age 90 of 5.7% and a second peak of bladder stones, commencing about age 50, with a projected prevalence of 1.9%. The prevalence of stone disease increases according to the order: single less than divorced/separated less than married less than widowed men. A family history of stones tends to be higher amongst relatives of stone-formers than amongst the corresponding relatives of control subjects, the male/female ratio being 2:1. The occurrence of urinary stones is significantly associated with that of gallstones, high blood pressure, backache, arthritis and gout but not with that of peptic ulcer, diabetes, thyroid disease or bronchitis.

Adult↗
PubMed1983

Jaw muscle afferent firing during an isotonic jaw-positioning task in the monkey.

The activity of jaw muscle receptors was studied by recording neurons in the mesencephalic nucleus of the trigeminal nerve in monkeys trained to control the position and movement of their mandible. Jaw position was measured by a weighted lever resting on the mandibular incisors. The force required to maintain the position of the lever was varied; in most cases it was either 25 or 360 g. Firing rates of neurons were related to stationary mandibular positions and to the velocity of movements during intervals when the movement velocity was constant. Of 49 neurons studied in detail, 21 fired at rates that were consistently and linearly related to static incisal openings. This static position sensitivity was typically about 5 spikes/mm of incisal opening. Most position-sensitive neurons fired at higher rates during opening movements and at lower rates during closing movements than would be accounted for by their position sensitivity. This sensitivity to the velocity of movement was not linear, however; slow closing movements sometimes did not produce a decrease in firing rate, and an actual increase during muscle shortening was seen in a few instances. The position sensitivity of eight neurons was evaluated during different loading conditions; in no case did it change substantially. Of the remaining 28 neurons, 26 fired at high rates during all opening movements and either stopped firing or fired at low, sporadic rates during closing movements. The static position sensitivity of these neurons was weak and variable both within and between neurons. The velocity sensitivity of these stretch-sensitive neurons was very nonlinear. Except for a range of slow movements (+/- 5 mm/s), the firing rate was maximal (200 spikes/s or higher) for most opening movements and zero for most closing movements. Maximal firing rates were higher when the loads being moved were increased from 25 to 360 g. The majority of position-sensitive neurons exhibited a large interspike-interval variability at wide incisal opening. In most of these neurons, this interspike-interval variability was periodic, usually at a rate of about 10 periods/s, and took the form of "saw-tooth" modulation on a record of instantaneous firing rate. Neurons that exhibited this modulation in a very prominent form also exhibited, in many instances, a substantial increase in firing rate during closing jaw movements.

Afferent Pathways↗
PubMed1983

Changes in the sentencing of diminished responsibility homicides.

The majority of men convicted of manslaughter by reason of diminished responsibility used to receive hospital orders, but are now receiving prison sentences. A sample of offenders convicted between 1966 and 1977 was studied to see the reasons for the change. It was found that the make-up of the offender population did not change materially over the period, nor did the willingness of judges to make hospital orders. What changed was the pattern of treatment recommendations made by the examining doctors in their court reports.

Adolescent↗
PubMed1983

Neurohypophysial peptides in the human fetus: presence in pituitary extracts of immunoreactive arginine-vasotocin.

A specific and sensitive radioimmunoassay was used to demonstrate the presence of arginine-vasotocin (AVT) in human fetal pituitary extracts. The mean pituitary contents of AVT in extracts of 70-101, 102-136 and 137-172 days gestation were 0.32, 0.8 and 8.1 ng/gland respectively. Combined high-pressure liquid chromatography (HPLC) and radioimmunoassay of pooled extracts at these gestational ages confirmed the presence of AVT. Radioimmunoassay of neonatal pituitary extracts (240-280 days) did not conclusively show AVT to be present, as the material assayed did not show parallelism with dilution. However, combined HPLC and radioimmunoassay of pooled extracts at this gestational age did demonstrate the presence of an immunoreactive AVT peak. Radioimmunoassay analysis of this peak indicated that a relatively small amount of AVT (at least 0.5 ng/gland) was present in the human pituitary gland at term.

Arginine Vasopressin↗
PubMed1983

Prison dentist.

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Delivery of Health Care↗