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S Talbot

Publications and source records attributed to S Talbot.

At least 19 recordsLinked to original sources
PubMed1992

Coagulation-factor deficiencies and abnormal bleeding in Noonan's syndrome.

Noonan's syndrome is characterised by a dysmorphic facies, congenital heart disease, and short stature, and is inherited as an autosomal dominant trait. Because abnormal bleeding has also been reported, we investigated a group of patients for coagulation-factor deficits. Of the 72 individuals studied (37 male, 35 female, mean age 11.4 years), 47 (65%) had a history of abnormal bruising or bleeding. 29 patients (40%) had a prolonged activated partial thromboplastin time. Specific abnormalities in the intrinsic pathway of coagulation (partial factor XI:C, XII:C, and VIII:C deficiencies) were found in 36 patients (50%). Multiple abnormalities among these 36 patients included combined factor XI:C and XII:C deficiencies (4 patients) and factor XI:C and VIII:C deficiencies (4), and 1 patient had combined factor VIII:C, XI:C, and XII:C deficiency. There was poor correlation between a history of abnormal bleeding and coagulation-factor deficit. In five families, similar coagulation-factor deficiencies were present in first-degree relatives with the syndrome. The pattern of inherited bleeding abnormalities seen in Noonan's syndrome suggests autosomal regulation of the intrinsic coagulation pathway.

Adolescent↗
PubMed1991

Pediatric poisoning from over-the-counter imidazoline-containing products.

We present two instructive cases of imidazoline poisoning in young children. Imidazoline decongestants, readily available in numerous non-prescription preparations, can rapidly produce toxicity from oral ingestion and topical application. Signs and symptoms depend on whether peripheral or central alpha 2-adrenergic receptor stimulation predominates. Timely diagnosis depends on a high index of suspicion and careful questioning about the availability of these over-the-counter products. Standard toxicologic management will prevent significant morbidity. No specific antidote exists.

Emergency Service, Hospital↗
PubMed1991

Regulatory domains within the P0 promoter of human c-myc.

Expression of P0 RNA in some Burkitt lymphoma cell lines varies independently of levels of RNA derived from P1 and P2. These data suggest the possibility that expression of P0 RNA may be capable of independent regulation. In order to investigate this possibility we have isolated putative regulatory domains flanking P0 RNA starts within the human c-myc gene and analysed both their ability to direct expression of control reporter genes and their ability to interact with specific transcription factors. Regulatory regions necessary for expression of P0 RNA have been located within 131 bp 5' of the first major P0 RNA start. DNAase 1 footprint analysis and gel retardation assays demonstrate binding of transcription factors Sp1, NF1 and CBP to this region. NF1 binds specifically to two consensus sequences. The more distal site overlaps with the binding site for CBP, and it is likely that concomitant binding of NF1 and CBP within the distal region of the P0 promoter is not possible. Previous work from our laboratory has described a negative regulatory domain within the 5' flanking region of c-myc. The P0 promoter resides within this domain and therefore may contain a negative regulator of c-myc gene expression.

Animals↗
PubMed1990

Cross-sectional internal diameters of human cervical and femoral blood vessels: relationship to subject's sex, age, body size.

Cross-sectional internal diameter measurements were made of right and left common carotid and right femoral arteries and right and left internal jugular, superficial femoral, and common femoral veins in 32 normal human subjects utilizing duplex ultrasonography. The relationships of these vessel sizes to the subject's sex, age, height, weight, and body surface area were analyzed statistically; and graphs were constructed, indicating the relationship of blood vessel diameters to the various body size parameters. Findings indicate that 1) for the femoral veins, body surface area had the best correlation with the internal diameter of the vein; 2) for the right internal jugular vein, body weight had the best correlation with the internal diameter of the vein; 3) correlation between vein diameter and body size of the subject is better for the femoral veins than for the internal jugular veins; 4) internal diameter of the femoral and internal jugular veins increases about 20% when they are distended by 15 degrees of positional inclination of the subject's body; 5) neither age nor sex of the subject influences the positional distensibility of the veins examined; 6) the cross-sectional internal diameter of the femoral and internal jugular veins, as determined by duplex ultrasonography, closely relates to the external diameter of these vessels as measured by direct in vivo application of calipers and to the maximum outside diameter of cannula the vessel will accept.

Adolescent↗
PubMed1989

Temporal changes in plasma and liver lipids and in the hepatic activities of acetyl-coenzyme a carboxylase and fatty acid synthetase after oestrogen treatment of the male chicken (Gallus domesticus).

1. Male chickens (Gallus domesticus) were treated with a single intramuscular injection of oestradiol-17 beta, then changes in the liver and plasma levels of triacylglycerol, phospholipid, nonesterified fatty acids and in the hepatic activities of acetyl-CoA carboxylase and fatty acid synthetase were measured at various times after injection. 2. The results suggest that the initial phase (less than 20 hr) of oestrogen-induced hyperlipidaemia occurs in the absence of changes in the hepatic activities of the major enzymes of fatty acid biosynthesis, but a subsequent increase in these enzyme activities may contribute to the later phase (greater than 20 hr) of oestrogen-induced lipogenesis in avian liver.

Acetyl-CoA Carboxylase↗
PubMed1989

Hyperammonaemic coma in ureterosigmoid urinary diversion.

We report on a patient with ureterosigmoid anastomosis, who presented with recurrent episodes of confusion, agitation and aggressive behaviour, culminating in coma. Investigations revealed profound hyperammonaemia, which responded to treatment with sodium benzoate and sodium phenylacetate. No definite cause was found for the abnormality, apart from possible urinary tract infection. The patient remains well on a protein restricted diet with mildly elevated levels of plasma ammonia.

Amino Acids↗
PubMed1988

Early effects of oestrogen treatment on lipogenesis de novo and on biosynthesis of triacylglycerol from fatty acids in male chick liver.

1. Early changes (0-44 hr) in liver and plasma lipid levels and in the rate of hepatic lipogenesis were measured in male chicks after a single intramuscular injection of oestradiol-17 beta. 2. Chick liver slices were employed to measure the rate of lipogenesis de novo using 3H2O and the rate of triacylglycerol synthesis from [9, 10-3H] palmitate at various times after injection. 3. The results suggest that oestrogen-induced lipogenesis occurs initially by a rapid and coordinated stimulation of the total hepatic capacity for lipogenesis de novo and for triacyglycerol synthesis from fatty acids. 4. The results are discussed in relation to oestrogen-induced changes in hepatic lipogenic enzymes.

Animals↗
PubMed1988

Transcriptional regulation of the human c-myc gene.

The involvement of c-myc in the genesis of animal neoplasia is now well documented for several systems. In order to define the precise role played by the myc gene in tumorigenesis, a better understanding of the normal regulation of myc expression is necessary. We have begun a study of the cis-acting regulatory sequences within the 5' flanking domain of the human c-myc gene. Regions important for myc promoter function have been identified by linkage to the coding sequences of the bacterial chloramphenicol acetyltransferase (cat) gene. Promoter deletion studies and in vivo competition assays for c-myc/cat recombinant plasmids have allowed the identification of a proximal 'core' promoter region capable of directing high levels of CAT activity. Further upstream a negative regulatory element (NRE2) has been identified which is capable of repressing cat gene expression and which functions by interaction with a transacting factor(s). Preliminary data suggests detection of NRE2 is dependent on both the type and amount of carrier DNA used in transient CAT assays. Initial experiments further indicate the involvement of at least two other distal regulatory domains, a negative regulatory domain (NRE1) and a putative enhancer-type region (E). In vitro footprint analysis has allowed the identification of DNA binding proteins which interact with NRE2 and the 'core' promoter. NRE2 contains binding sites for transcription factors Sp1 and CTF. The 'core' promoter domain appears to be highly complex and possesses several Sp1 binding sites.

Animals↗
PubMed1987

In vivo effects of corticosteroids on human allergic responses. I. Effects of systemic administrations of steroids.

In order to better understand the effects of corticosteroids in allergic disease, the relative degrees of allergen-induced cutaneous histamine release and granulocyte accumulation were evaluated in atopic volunteers following intravenous placebo or methylprednisolone administration. In nine subjects, a single intravenous dose of methylprednisolone (1 mg/kg) did not inhibit histamine release but did significantly reduce granulocyte accumulation at both allergen and buffer-challenged sites during five and one-half to six and one-half hours following steroid injection. These findings suggest that the corticosteroid-induced anti-inflammatory effects at allergic reaction sites do not include inhibition of local mediator release. Furthermore, the steroid-induced inhibition of inflammatory cell accumulation is not specific for the allergic reaction.

Administration, Oral↗
PubMed1985

Acquired hyper-IgM syndrome with necrotizing granuloma.

This article is highlighted by the finding of striking cervical lymphadenopathy in a patient with acquired hyper-IgM syndrome and the pathologic description of the involved nodes. Routine hematoxylin-eosin stains demonstrated the presence of idiopathic necrotizing granulomas in the nodal tissue, a finding not previously reported in this syndrome. Immunoperoxidase techniques were used to further characterize these granulomas and delineate the cellular composition of the nodal architecture. We found that the necrotizing granulomas consisted of a peripheral rim of Ia positive palisaded, epithelioid histiocytes and central areas of debris and scattered inflammatory cells that were T11 positive. In the uninvolved areas of the node, we observed a lack of IgG-bearing lymphocytes in germinal centers as well as an absence of IgG-containing and decreased IgA-containing plasma cells in interfollicular areas. In conjunction with these in situ observations, there was a lack of IgA and IgG immunoglobulin-secreting cell responses in pokeweed mitogen-stimulated cultures of the patient's peripheral blood mononuclear cells. Unique features of this article include: (1) the association of necrotizing granulomas with the hyper-IgM syndrome and (2) the use of monoclonal antibodies to characterize the distributions of nodal lymphocytes in a patient with this disorder.

Adult↗
PubMed1979

Lipid metabolites and nitrogen balance after abdominal surgery in man.

The relation of lipid metabolism to nitrogen balance was studied in patients having undergone abdominal surgery and was compared with control subjects who had fasted for a similar period. The patients had lower circulating concentrations of glycerol, non-esterified fatty acids and ketone bodies. There were inverse correlations between blood alanine and ketone body concentrations in both patients (r = -0.64, P less than 0.01) and controls (r = -0.58, P less than 0.01). Nitrogen excretion by patients (12.7 mmol/kg body weight/day +/- 1.4 s.e. mean) was greater than by controls (9.2 mmol kg(-1)d(-1) +/- 0.8, P less than 0.05), but a more marked difference was noted for urinary methyl histidine excretion of 5.1 +/- 0.5 mmumol kg(-1) d(-1) by patients and only 2.5 +/- 0.3 mumol kg(-1) d(-1) by controls (P less than 0.01), a disparity indicative of more active protein turnover after surgery.

Abdomen↗