Biomedical subjects
Publications and source records attributed to J F Smith.
The primary role of the board in developing a health care facility is to establish decisive policy regarding the building program. This article describes what is entailed in the development process; the makeup of the external consulting team; the hospital's internal review and decision-making process; and the issues and decisions the board must face.
Identical twin pairs of dairy cows (one twin being placed with 4 calves for multiple suckling while the other was machine milked) were used to study the hormonal changes associated with anoestrus. Experiments were conducted to examine the effect of multiple suckling on the interval to first oestrus post partum, concentrations of LH and progesterone post partum, and the LH response to LH-RH or oestradiol-17 beta. The effects of hormone therapy on anoestrus were also examined. Multiple suckled cows had a 5-9-week longer interval to first oestrus post partum than did their non-suckling twins in all trials. There were no significant differences between the suckling and non-suckling cows in basal plasma levels of LH. The suckling cows showed a delay of 2 and 6 weeks post partum in their response to LH-RH and oestradiol-17 beta respectively when compared with their non-suckling twins. Treatment with a progesterone-releasing intravaginal device and bromocriptine to lower prolactin levels did not reduce the interval to the first post-partum oestrus while treatment with the progesterone device and PMSG reduced the interval to both first oestrus and conception. These findings suggest that suckling affects the response of the hypothalamic-pituitary axis to both LH-RH and oestradiol in the post-partum cow.
Explore the source record for details and available documents.
Plasma concentrations of neurophysin I/II (N-I/II), 13,14-dihydro-15-keto-prostaglandin F (PGFM) and progesterone were measured by radioimmunoassay in plasma samples collected from four sheep at hourly intervals between 0700 and 1900 h from Days 12-17 of the estrous cycle. Plasma samples were also collected from a fifth sheep at 2-hourly intervals during Days 12-16 of the cycle. In all sheep, intermittent surges in the plasma concentrations of PGFM and N-I/II occurred during the period of luteal regression. On at least one occasion in each sheep a surge in the plasma concentration of N-I/II was observed coincident with a rise in PGFM concentrations. In general, the highest levels of N-I/II were observed early in luteolysis (Days 13-14 of the cycle) while the corresponding levels of PGFM in plasma were maximal around Day 15 when luteolysis was well advanced. It is suggested from this temporal data that oxytocin, which is considered to be released in association with N-I/II, may play an important role in ovine luteolysis by stimulating the secretion of prostaglandin F from the uterus during days 13-15 of the estrous cycle.
The content uniformity of hydrocortisone in seven commercially available brands of hydrocortisone ointment B.P. 1% has been investigated. Fifty 5 mg samples were assayed by high pressure liquid chromatography and the results indicated that for 95% confidence levels only two of the ointments exhibited no positive skewness, one exhibited a significant degree of positive skewness and four exhibited a highly significant degree of positive skewness. The extent of the skewed distributions is discussed in relation to previously published particle/agglomerate distributions for these ointments. The content uniformity in terms of the coefficient of variation CE calculated from the h.p.l.c. data is compared with the coefficient of variation CP that can be predicted from mixing theory on the basis of the particle/agglomerate distribution of the hydrocortisone. The departure from normality in drug content uniformity in the ointment is attributed to the hydrocortisone particles not being individually available for randomization, a large number being in an agglomerated form. That is, the manufacturing process is failing to achieve the full potential of the formulation by dispersing all of the agglomerates. Theoretical and experimental models predict that percutaneous absorption of drug may be enhanced over areas, where agglomerates are located, possibly not only resulting in localized toxicity but increased systemic availability. Drug content variability in small samples (5 mg) of topical steroid formulations could also effect the degree of skin blanching response in Mackenzie-Stoughton type tests since 5 mg portions containing in excess of twice the labelled strength were found. Regulatory control of content uniformity should be considered for certain topical steroids if unintentional over-dosage on small discrete areas is to be avoided.
1. The renal handling of purified human immunoglobulin light chain has been studied with an isolated perfused rat kidney preparation. 2. Human immunoglobulin light chain was freely filtered and largely reabsorbed. Fractional reabsorption was characteristic for each of four light chains and varied between 56% and 86%. No renal tubular maximum for human light chain was obtained. 3. Light chains at concentrations up to 10 times those seen in human myeloma were without effect on glomerular filtration rate or sodium and potassium reabsorption in experiments lasting up to 2 h. 4. Filtered and reabsorbed light chain returned ultimately to the perfusion medium, indicating a unique property of the tubular handling of this protein. None of the inhibitors tested (ouabain, frusemide, acetazolamide, probenicid) influenced light chain reabsorption. 5. The results are taken to indicate that light chain reaches the site of the transport enzyme, Na+,K+-dependent ATPase, at concentrations which vary with the nature of the light chain. This may provide a mechanism for renal damage in patients with myeloma, after prolonged exposure.
Explore the source record for details and available documents.
The paper describes the changes in the cricopharyngeal muscle in seven cases of dysphagia resulting from obstruction at this level which was relieved by myotomy. Histological features included degeneration and regeneration in the muscle fibres with interstitial fibrosis which was severe in some of the cases. It is considered that this restrictive fibrosis is the cause of the dysphagia and that it is secondary to muscle fibre damage, the cause of which is at present obscure. Minor degrees of muscle damage and regeneration were seen rarely in controls and fibrosis was never present. There was no evidence of underlying vascular or neurological disease in six cases; the seventh had a previous history of scleroderma but this was not thought to be the cause of the cricopharyngeal lesion. The age incidence ranged from 1 to 5 years at the onset of dysphagia; in six of the seven it was 50 years or more.
We investigated the recent claim that the vole agent, a rickettsia-like microorganism isolated from wild voles by Baker in 1946, is actually a strain of Rochalimaea quintana, the etiological agent of trench fever. The two organisms were compared on the basis of percent guanine-plus-cytosine content, genome size, deoxyribonucleic acid-deoxyribonucleic acid hybridization, polypeptide composition, and serological relationships. Although the two organisms do have identical or nearly identical deoxyribonucleic acid base ratios and show some serological cross-reactions, they differ substantially by all of the other criteria employed. They are clearly different, although possibly related, organisms. It remains to be determined whether they can be regarded as two species of the same genus. On the other hand, an Old World strain and a New World strain of R. quintana were indistinguishable from one another by the same criteria.
Plasma concentrations of progesterone and Provera were measured daily in 3 cows during 21 days of treatment with Provera-impregnated intravaginal sponges. Plasma concentrations of oestradiol-17beta and 13,14-dihydro-15-keto-prostaglandin F (PGFM) were measured hourly from 5 h before until 62 h after sponge removal. The profile of progesterone concentrations indicated that luteolysis occurred at the expected time (Days 19 to 23 of the cycle), even though plasma Provera concentrations were 150-250 pg/ml. The occurrence of peaks of PGFM after sponge withdrawal suggests that PGF-2alpha release is stimulated by falling levels of progestagen.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Androsteredione and testosterone were measured by radioimmunoassay after chromatography on micro-columns of Lipidex-5000 in jugular plasma samples taken every 2-3 h at the time of luteolysis and oestrus in 3 dairy cows. The concentrations of androstenedione and testosterone varied between 5 and 60 pg/ml and 5 and 80 pg/ml respectively and no consistent pattern in the fluctuations of either steroid was observed.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.