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Biomedical subjects

J F Smith

Publications and source records attributed to J F Smith.

At least 163 records · Page 9Linked to original sources

Squamous carcinoma arising in a pilonidal sinus.

A patient with squamous cell carcinoma arising from an extensive pilonidal sinus was treated with wide local excision, resulting in an apparent cure over a 1-year follow-up period. Review of the literature revealed 32 previously reported cases of this entity. Forty-four percent of these patients developed recurrences or metastases, and 22% died of their disease. The largest historical treatment group with at least 1-year follow-up (19 patients with localized disease) underwent wide excision. Forty-two percent of these patients recurred or developed metastases. Ultimately, 89.5% of these patients were reported cured, but only five survivors were followed for as long as 5 years. Historical experience appears to identify pilonidal tract squamous carcinoma as an aggressive tumor. The reported success of wide local excision is based on a small number of patients followed for short periods of time. Continued experience with this disease should be reported to verify the adequacy of local excision or identify the need for adjunctive therapy.

Adult↗

Histological diagnosis of carcinoma of the parathyroid gland.

During the period 1950-81, 678 cases of primary hyperparathyroidism were surgically treated at University College Hospital, London. The causes were a single adenoma in 575, two adenomas in 25, carcinoma in 20 (two of which had coexistent adenomas), chief cell hyperplasia in 56, and water clear cell hyperplasia in two. Histological diagnosis is not difficult except in some cases of carcinoma and in a few in which differentiation between recurrent hyperplasia and recurrent carcinoma is exceptionally difficult. In this paper we review all the cases of primary carcinoma of the parathyroid seen during this period to define those pathological features of value in the diagnosis.

Adenoma↗

Body composition prediction in university football players.

This study was intended to determine if previously-developed body composition prediction equations were valid for use with a Division I university football team. A sample of 68 Division I football players with a mean age of 19.7 yr, was assessed for body density (BD) by underwater weighing (UWW), residual volume by helium dilution, and 26 selected anthropometric measures. A predicted BD was obtained by using two sets of equations developed from college football players and from three generalized equations. The differences between predicted and observed body densities were analyzed. Seven of the nine models examined failed to accurately predict the BD for this population of university football players. One sport-specific equation of White, Mayhew, and Piper for individuals in the backfield and a generalized model of Jackson and Pollock (JP) containing two circumferences performed well when considering the mean of differences and the magnitude of total error relative to the published standard error. However, both of these models overestimate body density for players with low BD and underestimate BD when actual BD is high. Using the JP model for a player whose actual BD is near the sample mean of 1.070, the estimated mean is very close at 1.069. However, for players with actual BD of 1.050, the estimated mean is 1.054, and if actual BD is 1.085, the JP estimated mean is 1.078. The bias is linear between these points.

Adult↗

Comparative study of different urokinase preparations.

Three different urokinase preparations were assayed for amidolytic and plasminogen activator activity. It was found that the preparation with the least amidolytic activity displayed a significantly greater plasminogen activator activity than the others. These results suggest that this particular preparation may be more effective clinically and that the use of assay systems for the comparison of urokinase preparations must be treated with caution.

Endopeptidases↗

The comparison of solid phase and fibrin plate methods for the measurement of plasminogen activators.

A rapid and highly sensitive solid phase assay was compared with the fibrin plate method for the measurement of urokinase, streptokinase and the plasminogen activators in human euglobulin fractions. The solid phase assay was run using glu - or lys - plasminogen, and significant differences were observed in the activation of the plasminogens by urokinase and streptokinase. Plasminogen activator levels in euglobulin fractions were also measureable. Very good agreement was obtained between the fibrin plate and solid phase methods in all cases.

Endopeptidases↗

Effect of exogenous progestogens on plasma concentrations of the oxytocin-associated neurophysin and 13,14-dihydro-15-keto-prostaglandin F in intact and ovariectomized ewes over the time of expected luteal regression.

Plasma concentrations of the prostaglandin F metabolite 13,14-dihydro-15-keto-prostaglandin F (PGFM), the oxytocin-associated neurophysin (OT-N) and progesterone were monitored by radioimmunoassay (RIA) in five ewes sampled from the jugular vein at hourly intervals between 0700-1900 h from Days 12-16 of the estrous cycle. These hormones were also determined in plasma samples collected at similar times from five intact and five ovariectomized ewes given twice daily injections of medroxyprogesterone acetate (MPA) over Days 10 to 20 after the last observed estrus. In both the control and intact MPA-treated ewes, coincident surges of OT-N and PGFM were observed in jugular plasma during the time of luteal regression. No significant differences were noted in the number and amplitude of OT-N and number of PGFM peaks between the control and intact MPA-treated animals, although in the latter the amplitude of the PGFM peaks was significantly reduced (P less than 0.01). No marked surges in the plasma concentrations of PGFM or OT-N were observed in the ovariectomized ewes given exogenous MPA. This latter finding is consistent with previous proposals, suggesting that the ovaries are a major source of oxytocin in the ewe. In addition, the observation that exogenous progestogens in the intact ewes did not influence the number and peak height of the OT-N surges, indicates that a fall in progesterone levels during the normal cycle is not obligatory for oxytocin release although it may facilitate the release of uterine PGF2 alpha.

Animals↗

Embryonic suppression of oxytocin--associated neurophysin release in early pregnant sheep.

Pulsatile release of the oxytocin-neurophysin (OT-N) occurs during luteal regression in non-pregnant sheep. The effect on this neurophysin release by the presence of a conceptus was investigated. It was found that the transfer of an embryo, on either Day 12 or 13, to the uterus of a non-pregnant sheep inhibited the pulsatile release of OT-N. This result suggests that in the early pregnant sheep, the embryo may prevent corpus luteum regression by suppressing the pulsatile release of maternal oxytocin which is considered to induce the release of uterine prostaglandin F2 alpha.

Animals↗

Accuracy of imaging of the brains of newborn infants by linear-array real-time ultrasound.

Comparisons were made in 69 newborn infants of the appearance of the brain as visualised by linear-array real-time ultrasound, computerised tomography and at autopsy, in order to evaluate the accuracy of ultrasound for the detection of lesions in the brain. Ultrasound was found to give a good estimate of the presence and extent of haemorrhage into the germinal layer and ventricles, and also to be very useful for assessing the appearance of the ventricular system. Ultrasound diagnosed extradural haemorrhages but was unhelpful for identifying subarachnoid haemorrhages or lesions in the posterior fossa.

Atrophy↗

The incidence of topical steroid dilutions.

A survey of the prescribing pattern of topical treatment in a Family Practitioner Committee District revealed that 49.6% of topical preparations contained steroids and of these 11.2% were for diluted products. The majority (84%) of prescribed steroid dilutions on general practice prescription forms (F.P. 10's) were for Betamethasone-17-valerate and 83% required unrecommended diluent. The survey also revealed occasional prescriptions for high dilutions (e.g. 1 in 100 Betnovate) and unreported mixtures (e.g. Betnovate with Coal tar paste and antifungal proprietary creams mixed with steroid proprietaries). The examination of hospital prescriptions forms (F.P. 10 H.P.'s) was used to partially confirm the hypothesis that the practice of dilution and compounding of topical steroids is initiated in hospital and extrapolated to general practice.

Administration, Topical↗

Progressive renal failure in surgically treated hyperparathyroidism.

Of 570 patients operated on for hyperparathyroidism, 18 subsequently died (between one day and 12 yr after operation). Pathological findings at necropsy in these patients have been reviewed. Four necropsies on patients with untreated hyperparathyroidism have also been reviewed for comparison. Of these 22 cases, 14 had renal failure at the time of death. This was attributed to the following: nephrocalcinosis 6; chronic glomerulonephritis 4; analgesic nephropathy 1; cystinuria 1; sarcoidosis 1; and polycystic disease 1. Of those with renal failure due to nephrocalcinosis, three had persistent hypercalcaemia after operation; the other three survived only for a short time. There was no evidence of residual nephrocalcinosis producing progressive renal failure if the plasma calcium concentration was corrected. In those with chronic glomerulonephritis, cystinuria, and polycystic disease, the hyperparathyroidism was considered to be tertiary to the renal disease but renal failure was not always present at the time of diagnosis.

Adult↗

Prolongation of the oestrous cycle in cows and ewes after passive immunization with PGF antibodies.

Three cows and 2 sheep were passively immunized against prostaglandin (PG) F on Day 16 and Days 13-15 of the oestrous cycle respectively. The PGF antiplasma was raised in ovariectomized ewes against a PGF-2 alpha-bovine serum albumin complex and showed 100%, 12.5%, 0.3%, less than 0.05% and less than 0.01% cross-reactivity with PGF-2 alpha, PGE-2, PGA-2, PGB-2 and arachidonic acid, respectively. Control animals were given an equivalent amount of ovariectomized ewe plasma. In all passively immunized animals there was evidence of a persistent corpus luteum as indicated by plasma progesterone concentration and the failure of the animals to return to oestrus until at least 29 days after treatment. These data are consistent with previous proposals that PGF-2 alpha is the uterine luteolytic factor in sheep and cattle.

Animals↗