John A. Summerfield
Royal Free Hospital
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Journal of Hepatology | 1986
John A. Summerfield; Yukihisa Nagafuchi; Sheila Sherlock; J. Cadafalch; P.J. Scheuer
The clinical, radiological and hepatic histological features of 51 patients with hepatobiliary fibropolycystic disease were reviewed. Many of the patients had more than one of the diseases; the combination of both congenital hepatic fibrosis (CHF) and Carolis disease was most striking. Twelve patients with CHF (50% male) presented at 6 +/- 2 years of age (mean +/- SEM) with hepatosplenomegaly or variceal bleeding. Their main problems were recurrent variceal bleeds and renal disease. Polycystic kidneys and renal stones were present in 79% and chronic renal failure in 30%. Six of the 8 patients with Carolis disease were male (75%) and presented later (aged 37 +/- 8 years) with hepatomegaly or cholangitis. Recurrent cholangitis developed in most (7/8) and 2 had polycystic kidneys. Twelve patients had a combination of CHF and Carolis disease presenting with hepatosplenomegaly, bleeding or cholangitis. As in Carolis disease, most (83%) were male, but the age of presentation (15 +/- 4 years), and the incidence of polycystic kidneys (42%) and renal failure (8%) was intermediate between CHF and Carolis disease. In these patients, bleeds always predated cholangitis. Histologically, acute cholangitis was superimposed on the changes of CHF. Adult polycystic liver disease (10 patients) presented later (43 +/- 3 years) in females (90%) with pain, a mass or incidentally; polycystic kidneys were present in 33%. Microhamartomas (10 patients), which were usually incidental findings, were diagnosed latest (50 +/- 6 years). Three choledochal cysts were seen. The hazard of cancer in these diseases was reflected by 2 bile duct cancers and 1 pancreatic cancer (incidence 6%). This study has confirmed that hepatobiliary fibropolycystic diseases form part of a family and are often associated together. However, the diseases are of greatly differing severity and the prognosis in an individual patient is determined by the fibropolycystic diseases present.
Journal of Clinical Investigation | 1982
John A. Summerfield; John Vergalla; E. Anthony Jones
The cellular location and carbohydrate specificities of a glycoprotein recognition system on rat hepatic sinusoidal cells have been determined. Purified preparations of endothelial, Kupffer, and parenchymal cells were prepared by collagenase liver perfusion, centrifugation on Percoll gradients, and centrifugal elutriation. (125)I-labeled agalactoorosomucoid, an N-acetylglucosamine-terminated glycoprotein, was selectively taken up in vitro by endothelial cells. Uptake was shown to be protein dependent, calcium ion dependent, and saturable, and could be described by Michaelis-Menten kinetics (apparent K(m) 0.29 muM; apparent maximum velocity 4.8 pmol/h per 5 x 10(6) cells). Uptake was inhibited not only by N-acetylglucosamine, mannose, and mannan but also by glucose, fructose, and a glucose-albumin conjugate. Inhibition by glucose was competitive over a wide range of concentrations and was almost 100% at a glucose concentration of 56 mM. Fasting and the induction of diabetes mellitus prior to isolation of cells was associated with 60% reductions in the recovery of endothelial cells. Uptake by cells isolated from fasted rats was enhanced (apparent maximum velocity 14.3 pmol/h per 5 x 10(6) cells without change in the apparent K(m)). These observations suggest that fasting is associated with a marked increase in the mean number of glycoprotein receptors per endothelial cell isolated from normal rats. This effect of fasting could be due to upregulation of glycoprotein receptors on endothelial cells or to the selective isolation of a subpopulation of endothelial cells from fasted animals that bears more glycoprotein receptors per cell than does another subpopulation of these cells. In addition, in vivo studies of the fate of intravenously administered (125)I-agalactoorosomucoid indicated that its rate of disappearance from plasma, hepatic accumulation, and catabolism were slower in diabetic than in normal rats. The results suggest that modulation of a carbohydrate-mediated glycoprotein recognition system located on hepatic endothelial cells can be induced by glucose and glucose-conjugated proteins and by fasting and diabetes mellitus. The findings in this study suggest a mechanism for abnormal glycoprotein metabolism in diabetes mellitus.
Biochimica et Biophysica Acta | 1986
John A. Summerfield; Maureen E. Taylor
Human serum contains lectins which inhibit the uptake of mannose- and N-acetylglucosamine-terminated glycoproteins by isolated rat hepatic sinusoidal cells. In these experiments, calcium-dependent and calcium-independent human serum mannose-binding proteins have been isolated by affinity chromatography using mannan linked to four different supports. In electroblots both calcium-dependent and -independent serum mannose-binding proteins bound radioiodinated mannan and invertase in the presence of calcium ions, but the binding of calcium-dependent serum mannose-binding proteins was abolished by EDTA. Chicken antibodies were raised against serum mannose-binding proteins and an ELISA was developed. The principal calcium-independent serum mannose-binding protein is mannose-specific IgG as judged by immunodiffusion and electroblotting with anti-human IgG antibodies. The calcium-dependent serum mannose-binding protein is probably the secreted form of an intracellular hepatocyte mannose-binding protein since: antibodies raised against the 30 kDa subunit of the calcium-dependent serum mannose-binding protein also bound 30 kDa subunits of whole liver homogenate and purified human liver mannose-binding protein; antibodies to the human liver mannose-binding protein bound to the 30 kDa subunit of the calcium-dependent serum mannose-binding protein; and the binding specificities of the calcium-dependent serum mannose-binding protein for N-acetylglucosamine and fucose as well as mannose, and its recognition of the core region of an oligosaccharide rather than only the peripheral sugars, were identical to those reported for the hepatocyte mannose-binding protein. The physiological ligands of these serum mannose-binding proteins are unknown but they could bind noxious glycoproteins which enter the circulation prior to their removal by the sinusoidal mannose receptor.
British Journal of Haematology | 1984
D. A. Kelly; John A. Summerfield; Edward G. D. Tuddenham
Summary. Factor VIIIC: antigen (VIII: CAg) was estimated in guinea‐pig tissues by an immunoradiometric assay using a human inhibitor antibody. In homogenized guinea‐pig tissues, VIII: CAg was shown to be stable and to be predominantly located in the liver (9±1·2 units; mean ±SEM, n= 8). Lesser amounts were detected in spleen (1·3±0·02 units), lung (0·6±0·07) and kidney (0·4±0·06). In isolated liver cell fractions separated by centrifugal elutriation VIII: CAg was mainly detected in the hepatocyte fraction (0·3±0·07 units/108 cells; mean ± SEM, n= 5) and in lesser amounts in the endothelial (0·02±0·01 units/108 cells) and the Kupffer cell fractions (0·05±0·02 units/108 cells). The liver concentration of VIII:CAg was (0·17±0·02 units/g) which was 20% of the plasma concentration (0·96±0·01 units/ml, n= 8) suggesting that VIII: CAg may not be stored in the liver but is rapidly exported following synthesis.
Journal of Hepatology | 1986
M.C. Allison; Andrew K. Burroughs; P. Noone; John A. Summerfield
Bile duct perfusion with corticosteroids is reported to improve the cholangiographic and biochemical abnormalities in some patients with primary sclerosing cholangitis. In a randomised placebo controlled trial, thirteen consecutive patients received continuous bile duct irrigation with either normal saline (1 l/day) or normal saline plus hydrocortisone (100 mg daily) via a nasobiliary tube placed in a hepatic duct at endoscopic retrograde cholangio-pancreatography. Eleven patients completed lavage for 2 weeks but no cholangiographic changes were observed in either group. Liver function tests deteriorated during lavage, but later returned to pre-treatment levels. Although bile was sterile at start of lavage, a wide range of bacteria was isolated from bile in all patients during treatment, and cholangitis with septicaemia occurred in 2 patients. We conclude that nasobiliary lavage is not beneficial in treating primary sclerosing cholangitis.
British Journal of Dermatology | 1980
John A. Summerfield; Martin E. Welch
A sensitive electromagnetic movement detector has been developed to estimate itch by measuring scratch during sleep. The cumulative time of nocturnal limb movements of patients with itchy and non‐itchy liver diseases was estimated. Non‐itchy patients moved their arms for 24±9.3 min/8 h (mean ± s. d.) and their legs for 16 ± 7.0 min/8 h. The limb movements were not related to left or right handedness or the sex or age of the patient. Itchy patients had increased nocturnal limb movements; however, the increase in arm movement (up to five times control level) was much greater than the increase in leg movement (up to twice control level). The marked increase in arm movements in itchy patients supports the view that this movement is largely due to scratching. The reproducibility of the estimates of arm movements was reasonable (within‐person coefficient of variation 22%). In three studies, treatment resulted in a reduction of arm movements to normal levels. The measurement of cumulative nocturnal arm movement by these sensitive meters appears to be a valid estimate of scratch and superior to a subjective assessment of itch. The devices may also be applied to other studies, such as the effects of hypnotic drugs on sleep movement and the measurement of vibration.
Journal of Hepatology | 1986
M.C. Allison; Andrew K. Burroughs; P. Noone; John A. Summerfield
Bile duct perfusion with corticosteroids is reported to improve the cholangiographic and biochemical abnormalities in some patients with primary sclerosing cholangitis. In a randomised placebo controlled trial, thirteen consecutive patients received continuous bile duct irrigation with either normal saline (1 l/day) or normal saline plus hydrocortisone (100 mg daily) via a nasobiliary tube placed in a hepatic duct at endoscopic retrograde cholangio-pancreatography. Eleven patients completed lavage for 2 weeks but no cholangiographic changes were observed in either group. Liver function tests deteriorated during lavage, but later returned to pre-treatment levels. Although bile was sterile at start of lavage, a wide range of bacteria was isolated from bile in all patients during treatment, and cholangitis with septicaemia occurred in 2 patients. We conclude that nasobiliary lavage is not beneficial in treating primary sclerosing cholangitis.
British Journal of Haematology | 1985
D. A. Kelly; F. J. O'Brien; R.A. Hutton; Edward G. D. Tuddenham; John A. Summerfield; S. Sherlock
Summary. The components of the factor VIII complex were estimated by immuno‐ and bioassays in 85 patients with liver disease. The plasma concentrations of the antigens were elevated in 65% (VIII:CAg) and in 76% (VIIIR:Ag) of patients while the biological activites were elevated in only 14% (VIII:C) and 15% (VIII:RiCof). There was no correlation with C‐reactive protein, used as a measure of an acute phase reaction (χ2=0·7; P=0·1); or with severity of liver disease as judged by prothrombin ratio (P=1·0) but highest values were observed in patients with cholestatic liver disease. Following parenteral vitamin K there was a significant fall in both the biological activity of VIIIC (36%) and of VIII:CAg (38%) in 13 vitamin K deficient patients (P<0·001) but no change in 23 vitamin K replete patients or in the VIIIR:Ag levels in either group.
Journal of Hepatology | 1990
G.L. Kaye; John A. Summerfield; Neil McIntyre; James Dooley
Methyl tert butyl ether (MTBE) is a potent cholesterol solvent. We have used MTBE in twelve patients with 19 large radiolucent common bile duct stones which could not be removed endoscopically. MTBE was instilled directly into the common bile duct via a nasobiliary or percutaneous catheter. Successful clearance of the duct was achieved in ten patients. The stones disappeared completely in three patients with MTBE alone; in the remaining seven, it was possible to extract the stones endoscopically after MTBE, even though there was no change in the cholangiographic appearance. MTBE may have a role in the management of large retained common bile duct calculi but, given the practical difficulties of administration, its use should only be considered when other methods have failed and a non-surgical approach is desired.
Biochimica et Biophysica Acta | 1987
Maureen E. Taylor; John A. Summerfield
Two lectins with specificities for mannose and fucose have been isolated from human serum by affinity chromatography. One mannose-binding protein (MBP 1) has a native Mr of 700,000 with subunits of Mr 32,000 and has specificities for N-acetylglucosamine, N-acetylmannosamine and glucose as well as for mannose and fucose. The other mannose-binding protein (MBP 2) has a native Mr of 200,000 with subunits of Mr 28,000 and is specific only for mannose and fucose. MBP 2 appears to recognize the core sugars of asparagine-linked oligosaccharides as well as the terminal sugars. Both lectins are calcium-dependent, requiring approx. 0.095 mM calcium for half-maximal binding. MBP 1 binds maximally between pH 7-9, whereas MBP 2 has a pH optimum of 6-7. The binding activity of both proteins decreases rapidly below pH 5. The apparent association constants (Ka) for binding to mannon are 2.1 X 10(8) M-1 for MBP 1 and 1.3 X 10(8) M-1 for MBP 2. These data provide further evidence of the complex nature of mammalian carbohydrate recognition systems.