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S Fowler

Publications and source records attributed to S Fowler.

At least 73 records · Page 4Linked to original sources
PubMed1992

Steroid 21-hydroxylase is a major autoantigen involved in adult onset autoimmune Addison's disease.

An adrenal-specific protein reacting with autoantibodies in the sera of patients with adult onset Addison's disease has been purified from human adrenal glands. The protein, mol.wt. 55K, has the biochemical characteristics of steroid 21-hydroxylase and reacts on Western blots with rabbit antibodies to recombinant 21-hydroxylase. Absorption of the native human 55K adrenal protein with human adrenal autoantibodies prevented the subsequent reaction of the 55K protein with rabbit antibodies to 21-hydroxylase in Western blot analysis. In addition, human adrenal autoantibodies reacted with recombinant 21-hydroxylase expressed in yeast. These data indicate that the adrenal specific enzyme steroid 21-hydroxylase is a major autoantigen involved in adult onset autoimmune Addison's disease.

Addison Disease↗
PubMed1992

Comparative audit: an experimental study of 147,882 general surgical admissions during 1990.

In 1991, 1025 general surgical Fellows of The Royal College of Surgeons of England were circulated with a pro forma and asked to submit local audit results for admissions during 1990 to a confidential comparative audit service. The individual topics of cholecystectomy and colorectal resection were studied. Data returned by 160 surgeons concerned 147,882 admissions including 122,620 operations. Overall mortality rates ranged from 0 to 5 per cent and morbidity rates from 0 to 22 per cent. Laparoscopic cholecystectomy was associated with one-quarter of the mortality rate and two-thirds the morbidity rate of open cholecystectomy. Of the 33 surgeons who responded to a survey after the presentation of results, all wished to continue the exercise in future years; 39 per cent had been stimulated to perform further analyses and 15 per cent had changed practice habits as a result. Comparative audit involving large numbers of patients and surgeons is feasible and seems beneficial to participants.

Cholecystectomy↗
PubMed1992

Covering one eye affects how some children read.

The Dunlop Test was used to identify unstable binocular control in a group of 32 mixed-ability children. They were compared with 32 reading age-matched controls. The children were then asked to read two lists of single real words of equal linguistic difficulty: one with both eyes open and the other with the left eye occluded. Only children who failed the Dunlop Test made fewer non-word errors when they read with one eye. This result provides additional support for the theory that unstable binocular control can directly affect how children read. In addition, these findings suggest that this effect must be due, at least in part, to some interaction between the images from the two eyes.

Child↗
PubMed1991

What children see affects how they read.

Children of mixed abilities were given three single-word lists to read, matched for linguistic complexity. The visual component of the task was made harder by reducing the print size with each new list. The reading errors made by children who did and who did not have a visual impairment were compared. The visually impaired children's pattern of reading errors changed as their vision was stressed by the reduction in print size; their errors became non-words (neologisms). This finding suggests a link between the efficiency of visual processing and the accuracy of reading of these children.

Aptitude↗
PubMed1989

The effects of pregnant mare serum gonadotropin on follicular development, mating and pregnancy in mink.

Forty-four female ranch mink, maintained out-of-doors under standard conditions, were exposed to natural photoperiod supplemented with a period of artificial light from approximately 2300 hr to 0300 hr from early January to mid February. Breeding was initiated on March 1. After repeated attempts to breed the animals, it was determined that the likelihood of their breeding was very low, presumably due to the artificial and asynchronous long-day photoperiod. In an attempt to induce breeding, the mink were randomly assigned to one of four treatment groups: saline, 25 International Units (IU) PMSG, 37.5 IU PMSG and 50 IU PMSG. Significantly different (p less than 0.05) patterns of breeding success were observed following PMSG treatment. Approximately 90% of the 37.5 and 50 IU PMSG-treated females bred while only 30 to 50% of the females in the saline and 25 IU PMSG-treated groups bred. More importantly, there was a marked difference in successful pregnancies observed between the saline- and PMSG-treated animals. None of the saline-treated females bore offspring while 40% of the animals that were treated with PMSG gave birth, with litter size averaging between 4 and 5 kits per female. Histological evaluation of ovaries obtained from an additional 13 animals treated in a similar fashion demonstrated that PMSG treatment significantly increased the number of small follicles. These results demonstrate that the exogenous administration of PMSG has a potential application in increasing the reproductive efficiency of female mink with functional ovarian tissue yet rendered infertile due to other factors.

Animals↗
PubMed1988

Disordered vergence control in dyslexic children.

By means of a synoptophore vergence eye movements were recorded in dyslexic and normal children while they were attempting to track small targets moving in simulated depth. Of the dyslexic children 64% were unable to make proper vergence movements when macular sized fusion targets (2 1/2 degrees) were employed, but their vergence control was better for larger (7 degrees) targets. The normal readers and the remaining dyslexics showed normal vergence responses for both large and small moving fusion stimuli. The results suggest that many dyslexics suffer a disorder of visuomotor control and perception for stimuli falling on the macula; this may explain their characteristic visual problems when reading. Hence recording vergence eye movement responses to small moving fusion stimuli may be useful in the investigation and treatment of children with reading difficulties.

Child↗
PubMed1988

Improved separation of multi-locus hypervariable DNA restriction fragments by field inversion gel electrophoresis and fragment detection using a biotinylated probe.

DNA probes to multiple hypervariable human genomic loci are potentially highly informative as regards individual genome identification and parentage studies. However the resultant Southern blot patterns are generally highly complex and their interpretation difficult, with one important limitation being the extent of fragment separation and resolution. The separation of large DNA restriction fragments in agarose gels may be improved, in comparison to separations obtained by conventional electrophoresis, by the use of field inversion techniques. This is demonstrated by the analysis of the complex human Satellite III related DNA polymorphism. Detection of the Satellite III related restriction fragments is achieved either by using a [35S]-labelled probe (228S) or by using the same probe in a convenient non-isotopic form constructed by the photobiotin process. In addition, the probe 228S is useful for sexing the human genome, by the identification of a Y-specific restriction fragment.

Biotin↗
PubMed1985

Effect of monocular occlusion on visuomotor perception and reading in dyslexic children.

101 (68%) of 148 dyslexic children had unstable vergence eye movement control (unfixed reference) in the Dunlop synoptophore test. These children tended to make visual rather than phonemic errors when reading and writing; the opposite was true for those with stable control (fixed reference). The 148 dyslexic children were given plano spectacles to wear for 6 months when reading and writing and were randomised to receive either spectacles that had the left lens occluded or untreated ones. The trial was double blind. Conversion from unfixed to fixed reference occurred in 51% of the children who wore occluded spectacles, compared with 24% of those who wore plain spectacles. In the former group increase in reading ability improved by almost 6 months relative to change in age, whereas in those who wore plain spectacles and whose reference did not become fixed reading ability regressed by 0.4 months. The children with unfixed reference who did not benefit from occlusion were those who made not only visual but also phonemic and sequencing errors. Monocular occlusion may thus help one-sixth of dyslexic children to develop reliable vergence control and thereby to read.

Child↗
PubMed1983

Pox virus infection of a domestic cat.

Pox virus infection of a domestic cat is reported. It was manifest clinically as a skin infection which resolved within two months. Histopathology and electron microscopy of the epidermis revealed inclusion bodies typical of pox virus infection. Serological examination of convalescent serum confirmed recent pox virus infection. Cow pox virus was considered as the most likely infectious agent in this case.

Animals↗
PubMed1983

Arterial neutral cholesteryl esterase. A hormone-sensitive enzyme distinct from lysosomal cholesteryl esterase.

We describe here an activable neutral cholesteryl esterase (EC 3.1.1.13) in arteries similar to the hormone-sensitive lipase of adipose tissue and adrenal cortex. Maximum enzyme activity in rabbit aorta was given by cholesteryl ester substrates dispersed as a mixed micelle with phosphatidylcholine and Na taurocholate (molar ratio 1:4:2). A quantitative assay of enzymic activity was obtained with the following component concentrations: 6.0 microM cholesteryl [1-14C]oleate, 23.7 microM phosphatidylcholine, 12.5 microM Na taurocholate, 0.04% serum albumin, and 85 mM K phosphate buffer, pH 7.0. The enzymic activity in aortic homogenates was stimulated 2-fold by addition of 5 microM glucagon or 100 microM dibutyryl cAMP. This activation was Mg-ATP dependent. Addition of 50 micrograms/ml of exogenous protein kinase could reverse the action of protein kinase inhibitor on dibutyryl cAMP activation of the neutral cholesteryl esterase. In addition to activation by cAMP-dependent protein kinase, the enzyme could be distinguished from the more active arterial lysosomal cholesteryl esterase by its pH 7.0 optimum, relative stability to preincubation at elevated temperatures, and exclusive localization in the cell cytosol. Subcellular fractionation of lipid-laden arterial foam cells revealed a significant portion of the neutral cholesteryl esterase bound to cytoplasmic cholesteryl ester-rich lipid droplets. Our results suggest that the breakdown of cytoplasmic cholesteryl ester droplets in arterial cells may be under hormonal regulation.

Animals↗
PubMed1982

Polypeptide and phospholipid composition of the membrane of rat liver peroxisomes: comparison with endoplasmic reticulum and mitochondrial membranes.

Membranes were isolated from highly purified peroxisomes, mitochondria, and rough and smooth microsomes of rat liver by the one-step Na2CO3 procedure described in the accompanying paper (1982, J. Cell Biol. 93:97-102). The polypeptide compositions of these membranes were determined by SDS PAGE and found to be greatly dissimilar. The peroxisomal membrane contains 12% of the peroxisomal protein and consists of three major polypeptides (21,700, 67,700 and 69,700 daltons) as well as some minor polypeptides. The major peroxisomal membrane proteins as well as most of the minor ones are absent from the endoplasmic reticulum (ER). Conversely, most ER proteins are absent from peroxisomes. By electron microscopy, purified peroxisomal membranes are approximately 6.8 nm thick and have a typical trilaminar appearance. The phospholipid/protein ratio of peroxisomal membranes is approximately 200 nmol/mg; the principal phospholipids are phosphatidyl choline and phosphatidyl ethanolamine as in ER and mitochondrial membranes. In contrast to the mitochondria, peroxisomal membranes contain no cardiolipin. All the membranes investigated contain a polypeptide band with a molecular mass of approximately 15,000 daltons. Whether this represents an exceptional common membrane protein or a coincidence is unknown. The implications of these results for the biogenesis of peroxisomes are discussed.

Animals↗
PubMed1982

Isolation of intracellular membranes by means of sodium carbonate treatment: application to endoplasmic reticulum.

A rapid and simple method for the isolation of membranes from subcellular organelles is described. The procedure consists of diluting the organelles in ice-cold 100 mM Na2CO3 followed by centrifugation to pellet the membranes. Closed vesicles are converted to open membrane sheets, and content proteins and peripheral membrane proteins are released in soluble form. Here we document the method by applying it to various subfractions of a rat liver microsomal fraction, prepared by continuous density gradient centrifugation according to Beaufay et al. (1974, J. Cell Biol. 61:213-231). The results confirm and extend those of previous investigators on the distribution of enzymes and proteins among the membranes of the smooth and rough endoplasmic reticulum. In the accompanying paper (1982, J. Cell Biol. 93:103-110) the procedure is applied to peroxisomes and mitochondria.

Animals↗
PubMed1982

Diagnosis of dyslexia by means of a new indicator of eye dominance.

Many dyslexic children are unable accurately to control the movements of their eyes even when they are not trying to read. This immaturity helps to explain their visual confusions. It may result from failure to develop dependable associations between retinal and ocular motor signals these are essential to fix the true, as opposed to retinotopic, locations of objects in the outside world. We have used a new test to study retinal/ocular motor correspondence in dyslexic children and age/IQ matched normal readers. Over half the dyslexics showed unstable ocular motor dominance.

Child↗