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Background and aims: Chronic idiopathic intestinal pseudo-obstruction (CIIP) is a severe motility disorder associated with significant morbidity. Several histopathological (neuropathic and myopathic) phenotypes have been described but only a single adult with jejunal smooth (circular) muscle α-actin deficiency. We present a prospective multinational case series investigating smooth muscle α-actin deficiency as a biomarker of this disease. Methods: A total of 115 fully clinically and physiologically (including prolonged (24 hour) ambulatory jejunal manometry) characterised CIIP patients from three European centres were studied. Immunohistochemical localisation of actins and other cytoskeletal proteins were performed on laparoscopic full thickness jejunal biopsies and compared with adult controls. Distribution of α-actin was also characterised in other gut regions and in the developing human alimentary tract. Results: Twenty eight of 115 (24%) CIIP patient biopsies had absent (n = 22) or partial (n = 6) jejunal smooth muscle α-actin immunostaining in the circular muscle layer. In contrast, smooth muscle α-actin staining was preserved in the longitudinal muscle and in adult jejunal controls (n = 20). Comparative study of other adult alimentary tract regions and fetal small intestine, suggested significant spatial and temporal variations in smooth muscle α-actin expression. Conclusions: The ability to modulate α-smooth muscle actin expression, evident in development, is maintained in adult life and may be influenced by disease, rendering it a valuable biomarker even in the absence of other structural abnormalities. [ABSTRACT FROM AUTHOR]

Bile acid levels were measured in the sera, cerebrospinal fluid (CSF), and brain tissue of 10 patients immediately after death from fulminant hepatic (FHF). Serum bile acids in FHF were predominantly conjugated, and total bile acid levels were higher in all 10 patients than in normal controls (85.9 +/- SE 8.4 compared with 5.7 +/- 0.4 nmol/ml, P less than 0.001). Small but significant amounts could be detected in CSF (range 1.2-5.3 nmol total bile acid/ml) and brain biopsies (1.0-18.8 nmol/g wet weight) of FHF patients, whereas none could be detected in CSF and brain biopsies of patients dying without evidence of liver disease. There was no relationship between serum, CSF, or brain levels and duration of coma, or presence of cerebral oedema found in five FHF patients at necropsy. However, serum bile acid levels were similar in FHF to those found in chronic liver disease without encephalopathy and lower than those found to inhibit brain respiration in vitro. A primary role for these compounds in the pathogenesis of coma in FHF therefore seems unlikely. [ABSTRACT FROM PUBLISHER]

In order to investigate the source of free amino acids found in the gut lumen during absorption of dipeptides, as well as evaluating the role of brush border peptidases in the mucosal hydrolysis of dipeptides during absorption, rates of dipeptide disappearance and appearance of hydrolytic products were measured during perfusion of rat jejunum and ileum in vivo with buffered and unbuffered 10 mM solutions of glycl-L-phenylalanine (Gly-Phe) and L-phenylalanyl-glycine (Phe-Gly). Mucosal brush border peptidase activity was then measured in the perfused segments in vitro at luminal pH and at two substrate concentrations. In addition cytosol peptidase activity in the perfused segments was measured at pH 7-4 and at 10 mM substrate concentrations. In the jejunum, there was a relationship between rates of free phenylalanine appearance in vivo (Phe-Gly greater than Gly-Phe) and rates of brush border (Phe-Gly greater than Gly-Phe) rather than cytosol (Gly-Phe greater than Phe-Gly) peptidase activities. No constant relationship between free phenylalanine appearance and hydrolysis of the dipeptides by either brush border or cytosol peptidases was observed in the ileal studies. These findings suggest that, in the jejunum, hydrolytic products originate from the surface of the cell whereas, in the ileum, hydrolytic products originate from both the intracellular compartment as well as from the surface of the mucosal cell. In the jejunum, in vitro rates of brush border hydrolysis of Gly-Phe were always less than in vivo disappearance rates, whereas rates of Phe-Gly brush border hydrolysis always exceeded luminal disappearance rates. These data imply that Gly-Phe is predominantly transported intact and hydrolysed by cytosol peptidases, In contrast, brush border peptidases play an importnat role in the mucosal hydrolysis of Phe-Gly. [ABSTRACT FROM PUBLISHER]

A double-lumen perfusion technique has been used to investigate jejunal and ileal absorption of glucose, water, and electrolytes in a group of patients with untreated adult coeliac disease. Correct positioning of the tube was confirmed by measuring the differential jejunal and ileal handling of bicarbonate. Eight control subjects and eight patients with coeliac disease were perfused with an isotonic electrolyte solution containing 50 mM glucose and 25 mM bicarbonate. The group of coeliac patients had impaired jejunal absorption of glucose (P less than 0.001), water (P less than 0.01), sodium (P less than 0.02), and chloride (P greater than 0.05) compared with the control group. In contrast the group of coeliac patients had normal ileal glucose and water absorption and increased ileal sodium (P greater than 0.01) and chloride (P greater than 0.05) absorption compared with the controls. Evidence for ileal adaptation was found in three individual patients who had absorptive values outside 2SD of the normal mean. The results indicate that the distal small intestine in coeliac disease has the ability to adopt to the damage and loss of absorptive capacity in the proximal small intestine. [ABSTRACT FROM PUBLISHER]

The characteristics of glucose, glycine, L-alanine, and glycyl-L-alanine absorption from the jejunum and ileum have been compared in normal human subjects. A perfusion technique has been used, and correct positioning of the perfusion tube has been confirmed by measuring the differential jejunal and ileal handling of bicarbonate. Glucose and glycine were absorbed faster from the jejunum than from the ileum of all subjects studied, and L-alanine was absorbed faster from the jejunum than from the ileum in five out of six subjects studied. In contrast, the dipeptide glycyl-L-alanine was absorbed at comparable rates from the jejunum and ileum. Higher concentrations of free amino acids were detected in the luminal contents aspirated during the ileal dipeptide perfusions. These results emphasize the importance of oligopeptide transport in the absorption of protein digestion products, especially in the human ileum, and the practical implications of these findings are discussed. [ABSTRACT FROM PUBLISHER]

A double-lumen perfusion technique has been used to study amino acid and peptide absorption in eight normal control subjects, 13 patients with untreated adult coeliac disease, and 16 patients with dermatitis herpetiformis who had varying morphological abnormalities of the small bowel. All subjects were perfused with isotonic solutions containing 10 mM glycyl-L-alanine and 10 mM glycine + 10 mM L-alanine. Patients with adult coeliac disease had impaired absorption of glycine (p < 0·01) and L-alanine (p < 0·05) from the amino acid solution compared with the control subjects. Amino acid uptake from the dipeptide solution was not significantly impaired, although four individual patients had impaired uptake of both amino acids. In contrast to these findings, very few patients with dermatitis herpetiformis had impaired amino acid absorption from either solution. Sodium absorption was impaired from both solutions when the groups of patients with adult coeliac disease and dermatitis herpetiformis with subtotal villous atrophy and partial villous atrophy were studied, and there were patients in each group who secreted sodium and water. The results suggest that malabsorption of dietary protein is unlikely to occur in dermatitis herpetiformis but may occur and contribute to protein deficiency seen in some severe cases of adult coeliac disease. The impairment of sodium and water absorption provides evidence that there may be functional impairment of the jejunal mucosa in dermatitis herpetiformis as well as in adult coeliac disease. [ABSTRACT FROM PUBLISHER]

The recent launch of a number of fibre enriched polymeric diet in the United States and Europe has stimulated considerable interest in the topic of fibre and enteral nutrition, and several commercial concerns appear to be under considerable pressures from their consumers to produce similar products. As a means of identifying areas of potential application of fibre to enteral nutrition some of the recent knowledge gained about the physical properties of dietary fibre and the processes involved in the intestinal assimilation of fibre has been reviewed. Two areas of interest are identifiable. The first relates to the bulking properties of fibre and the application of this to the regulation of bowel function in enterally fed patients. It is clear from the clinical studies that have been reviewed that there remains a paucity of controlled data, and a great deal more research is needed before widespread use of fibre supplemented diets can be supported. Perhaps of greater interest academically is the potentially beneficial effects that appear to be exerted by the VFA's, liberated as a consequence of colonic bacterial fermentation of fibre, on morphology and function of ileal and colonic mucosa. Although there are a number of potential applications of fibre supplemented enteral diets in this area, more research is required before any firm recommendations can be made about recommending their use. The one exception concerns patients with the nutritionally inadequate short bowel syndrome. There does seem to be sufficient experimental evidence to suggest that clinical studies should be commenced using a pectin supplemented predigested 'elemental' diet in these patients. Overall therefore, one is forced to conclude that the increasing interest and use of fibre supplemented enteral diets is being driven more by market than scientific forces. Nevertheless, the promotion of these diets has already provided a powerful stimulus to the scientific community, and it remains entirely possible that many of the potential applications of these diets will be realised in the near future. [ABSTRACT FROM PUBLISHER]

Results of recent controlled studies show that because of difficulties in administering adequate quantities of enteral diet, positive nitrogen balance is not consistently achieved during enteral feeding. In order to determine whether nitrogen balance can be improved in routine clinical practice by prescribing enteral diets containing higher concentrations of nutrients, 118 patients with normal gastrointestinal function needing enteral nutrition were randomised to receive daily 21 of one of three polymeric diets: Standard diet (1.0 kcal/ml; 6.3 gN/l), Energy Dense diet (1.5 kcal/ml; 7.8 gN/l), and Energy-Nitrogen Dense diet (1.5 kcal/ml; 9.4 gN/l. The three diets, administered by continuous nasogastric infusion, were equally well tolerated. Results were analysed only for patients fed five or more days and who received at least 60% of prescribed enteral diet (n = 42). Positive nitrogen balance was achieved only in the patients receiving the Energy-Nitrogen Dense diet (n = 16; + 1.6 (SE) 0.6 gN/d, compared with the Standard diet (n = 12; -3.8 (1.1) gN/d; p less than 0.001), and the Energy Dense diet (m = 14; -1.9 (0.8) gN/d; p less than 0.005). As the findings of this prospective controlled trial show that positive nitrogen balance was not consistently achieved by administering 21 enteral diet containing up to 15.6 gN, consideration could, therefore, be given to routinely using enteral diets containing up to 9.4 gN/l. [ABSTRACT FROM PUBLISHER]

The fate of orally ingested lactitol, a non-absorbed sugar, was measured in six healthy human subjects by following the three routes of disposal of universally 14C-labelled sugar. Lactitol was given as a 20 g daily dose to six healthy volunteers for 14 days and on the seventh day, 10 muCi of L-[U-14C]-lactitol was given with the unlabelled sugar and excretion of the 14C in breath, urine and faeces was followed. The peak of 14CO2 excretion occurred at six hours and total 14CO2 accounted for 62.9 (5.0)% of isotope given, whilst 6.5 (3.6)% and 2.0 (0.3)% of the label were recovered from faeces and urine respectively. These data suggest that lactitol is extensively metabolised in the human colon and that a significant proportion of the bacterial metabolites are available for colonic absorption. Calculation revealed that 54.5% of the theoretical energy content of this compound was utilised by the subjects. It is suggested that this sugar, and other soluble 'non-absorbed' sugars (lactulose, sorbitol, mannitol), may undergo a similar pattern of colonic metabolism and can be considered as reduced calorie compounds. [ABSTRACT FROM PUBLISHER]

Previous studies have shown that ileal infusion of partially digested triglyceride inhibits jejunal motility. The partial digest used in those studies contained a mixture of glycerol, free fatty acid, mono-, di-, and triglycerides. In Part I of the present study we have separately infused emulsions containing either glycerol 3.1 g (n = 6), oleic acid 9.6 g (n = 6), triolein 10 g (n = 12), or medium chain triglycerides 10 g (n = 6) into the ileum and have recorded the effect this has on jejunal motility. Five further subjects received infusions of partial hydrolysates of corn starch 10 g and lactalbumin 7 g. Marked inhibition of jejunal pressure wave activity was seen after all three lipid infusions, per cent activity falling from a control of 37.7 (7.7) to 6.2 (2.1) and 22.4 (8.2)% 30 min after completing the oleic acid and triolein infusions respectively, and from a control value of 39.5 (4.1) to 17.7 (4.7) after MCTs (all p less than 0.05). No significant fall occurred after infusion of glycerol, protein or carbohydrate. All three lipid infusions raised plasma concentrations of neurotensin, enteroglucagon and peptide YY equally effectively, although only the rise in peptide YY correlated significantly with the inhibition of jejunal pressure wave activity (r = 0.80, n = 6, p less than 0.05). In Part II of this study six subjects received a 3 ml/min jejunal infusion of an isotonic carbohydrate saline solution followed after three hours by a similar infusion of a partial digest of lipid. During each infusion flow and transit time was measured by marker and dye dilution. Jejunal infusion of the carbohydrate-saline solution was associated with low jejunal flow, 4.7 (1.0) ml/min and a mean transit time through the 50 cm study segment of 36.5 (7.1) min. By contrast jejunal infusion of partially digested triglyceride was associated with a markedly increased flow, 9.0 (1.2) ml/min, a fall in mean transit time to 20.3 (2.6) min and significant rises in pancreaticobiliary secretions. Jejunal triglyceride also increased the incidence of prolonged high amplitude jejunal pressure waves in four of six subjects. These studies suggest that there are important differences in the jejunal response to ileal versus jejunal lipid. While long and median chain free fatty acids infused into the ileum exert an inhibitory effect on jejunal motility, when infused directly into the jejunum partially digested triglyceride accelerates transit, increases jejunal flow and subtly alters the pattern of jejunal contractions. [ABSTRACT FROM PUBLISHER]

Mouth-caecum transit time (M-CTT) of a lactulose labelled liquid test meal has been measured in 27 coeliac patients and 10 healthy controls using the breath hydrogen technique. Although all patients were urged to maintain a gluten free diet, not all did, and there was, therefore, a wide range in the severity of fat malabsorption within the patient group. Gastric emptying of a 113Indium DTPA-labelled liquid test meal was also assessed in separate studies on six healthy controls and 11 of the coeliac patients. Fasting breath hydrogen concentrations and the response to lactulose, as assessed both by the rate of rise, and the peak breath hydrogen concentration reached, showed no difference between coeliacs and controls, regardless of the presence or absence of steatorrhoea. Mouth-caecum transit time in the 16 coeliac patients with steatorrhea (faecal fat greater than 7 g/24 h) was, however, significantly prolonged being 158 +/- 18 minutes (mean +/- SEM), compared with 70 +/- 9 minutes for the controls (p less than 0.02), and 83 +/- 15 minutes for the 11 coeliacs without steatorrhoea (p less than 0.002). Mouth-caecum transit time in the coeliac patients was linearly related to the 24 hour faecal fat excretion, r = 0.55, n = 27, p less than 0.01. Slow mouth-caecum transit in the coeliacs with steatorrhoea was not caused by delayed gastric emptying as the t1/2 for coeliacs with steatorrhoea was within the normal range. Coeliacs with delayed mouth-caecum transit had impaired insulin release but the postprandial profiles of the other peptides measured (cholecystokinin, GIP, secretin, motilin, neurotensin, enteroglucagon, and peptide YY) were all within the normal range in this group of partially treated coeliac patients. [ABSTRACT FROM PUBLISHER]

Jejunostomy losses of Na+ and water during enteral nutrition after massive intestinal resection may be severe. We have attempted to analyse this practical problem by using an in vivo perfusion technique in healthy volunteers to study Na+, water and nutrient absorption from a short (25 cm) segment of jejunum during perfusion of an isotonic solution of the elemental diet Vivonex. Further solutions made from the amino acid and carbohydrate components of Vivonex were also perfused in part I of the study in order to determine the causes of the marked Na+ and water secretion seen during Vivonex perfusion. Low initial Na+ concentration was found to be the major determinant of net Na+ secretion, initial Na+ concentration correlating significantly with Na+ absorption (r = 0.95, n = 7 p less than 0.001). Water absorption correlated with net absorption of NaCl (r = 0.82, n = 7 p less than 0.01). There was, however, a better correlation with total absorption of NaCl plus amino acids (r = 0.99, n = 7, p less than 0.01). In part II of the study separate isotonic solutions of NaCl, glucose, and the polymeric diet, Ensure were also studied. Net sodium secretion occurred during glucose and Ensure perfusion, as predicted from their low Na+ concentration. Owing to rapid sucrose absorption from Ensure there was substantial luminal disappearance of osmotically active particles and hence marked water absorption, which was accurately predicted using the regression equation for water absorption derived in part I, substituting sucrose absorption for amino acid absorption. We conclude that the marked Na+ and water secretion observed during Vivonex perfusion is not a unique property of this amino acid based diet but is due to its low Na+ content. [ABSTRACT FROM PUBLISHER]

Lactitol, an unabsorbed sugar with defined laxative threshold and superior taste properties has been suggested as an alternative to lactulose in the treatment of hepatic encephalopathy. In the present study we have compared the colonic metabolism of the two sugars using an in vitro faecal incubation system. Both sugars were readily metabolised by faecal bacteria producing volatile fatty acids and the metabolism was inhibited by neomycin. The effect of lactitol and lactulose on terminal ileal and colonic pH was monitored in six normal subjects using a radiotelemetry technique. Both sugars significantly lowered right colonic pH (basal -6.51 +/- 0.48 vs lactitol -5.63 +/- 0.50; lactulose -5.18 +/- 0.82, p less than 0.05). The pH of rest of the colon and terminal ileum was unaffected. Neomycin given concurrently with lactulose abolished acidification of right colon. As lactitol and lactulose have similar effects within the colon, lactitol would appear to have a role in the treatment of hepatic encephalopathy. As neomycin antagonises the effect of lactulose in the colon, its concurrent use may be less effective in the treatment of hepatic encephalopathy. [ABSTRACT FROM PUBLISHER]

Although there has been agreement that enteral nutrition remains an excellent means of providing nutritional support to malnourished patients with normal or near normal gastrointestinal function, it is clear that areas of controversy do exist, and attention needs to be directed towards these in the future. [ABSTRACT FROM PUBLISHER]

Between 1973 and 1983 abdominal tuberculosis was responsible for the admission of 90 patients to a west London district general hospital. Over the same period Crohn's disease was newly diagnosed in 102 hospitalised patients. In contrast with Crohn's disease, the majority (75) of tuberculous patients were Asian immigrants. Mean duration of residence in the United Kingdom was 4 +/- 0.9 (SD) years, and mean age at presentation was 34.9 +/- 1.1 years. Forty per cent of tuberculosis patients presented as an acute emergency to physicians, surgeons, or gynaecologists while the remainder presented a more insidious, chronic picture. Five groups of tuberculous patients were recognised. Forty two subjects had intestinal tuberculosis characterised by pain (100%), abdominal mass (43%) and abnormal contrast radiology (100%). Ten of these underwent emergency laparotomy for intestinal obstruction or perforation. Twenty seven patients had tuberculous peritonitis although only 16 had ascites. Eight patients presented with pyrexia and granulomatous hepatitis. Five had pulmonary and abdominal tuberculosis. The remaining eight patients represented a miscellaneous group. The diagnosis of abdominal tuberculosis was established histologically (60 cases), bacteriologically (six cases) or radiologically (24 cases). Chest radiograph, tuberculin skin testing and paracentesis were usually unhelpful. Five severely ill patients died. The remainder recovered completely after specific triple chemotherapy and response to treatment was usually evident within 14 days. In urban Britain tuberculosis is an important cause of abdominal disease. Prognosis is excellent following specific therapy. [ABSTRACT FROM PUBLISHER]

An intestinal perfusion technique has been used in normal human subjects to investigate the influence that starter protein composition and hydrolysis procedure have on absorption of amino acid residues from partial enzymic hydrolysates of whole protein. Five starter proteins were studied. Three (egg albumin, casein/soy/lactalbumin, and lactalbumin) were hydrolysed by papain, a second lactalbumin starter protein, and a meat/soy/lactalbumin blend were hydrolysed by a porcine pancreatic enzyme system. Irrespective of starter protein composition or hydrolysis method used, four amino acid residues (threonine, glutamic acid, phenylalanine, and histidine) were absorbed significantly faster from all hydrolysates compared with absorption from their equivalent free amino acid mixtures. In contrast, both starter protein composition and hydrolysis method influenced absorption characteristics of up to nine other amino acid residues. [ABSTRACT FROM PUBLISHER]

The possibility that malabsorbed fat passing through the human ileum exerts an inhibitory feedback control on jejunal motility has been investigated in 24 normal subjects by perfusing the ileum with a fat containing solution designed to produce ileal luminal fat concentrations similar to those in steatorrhoea (30-40 mg/ml). Mean transit times through a 30 cm saline perfused jejunal segment were measured by a dye dilution technique. Thirty minutes after ileal fat perfusion, mean transit times rose markedly to 18.9 +/- 2.5 minutes from a control value of 7.5 +/- 0.9 minutes (n = 5; p less than 0.05). This was associated with an increase in volume of the perfused segment which rose to 175.1 +/- 22.9 ml (control 97.6 +/- 10.3 ml, n = 5; p less than 0.05). Transit times and segmental volumes had returned towards basal values 90 minutes after completing the fat perfusion. Further studies showed that ileal fat perfusion produced a pronounced inhibition of jejunal pressure wave activity, percentage duration of activity falling from a control level of 40.3 +/- 5.0% to 14.9 +/- 2.8% in the hour after ileal perfusion (p less than 0.01). Ileal fat perfusion was associated with marked rises in plasma enteroglucagon and neurotensin, the peak values (218 +/- 37 and 68 +/- 13.1 pmol/l) being comparable with those observed postprandially in coeliac disease. These observations show the existence in man of an inhibitory intestinal control mechanism, whereby ileal fat perfusion inhibits jejunal motility and delays caudal transit of jejunal contents. [ABSTRACT FROM PUBLISHER]

The intestinal absorption and mucosal hydrolysis of a partial and a complete alpha-amylase hydrolysate of corn starch, simulating the normal intermediary and end products of luminal starch digestion, was studied using an in vivo steady state jejunal perfusion technique in normal human subjects. Alpha-amylase was excluded from the test segment by proximal balloon occlusion. Products of hydrolysis during intestinal perfusion were identified using gel permeation chromatography. Three isocaloric, isotonic sugar saline solutions containing 140 mM glucose, 70 mM maltose and the partial amylase hydrolysate of starch (51.5 +/- 1.4% of glucose content comprising glucose polymers of more than 10 glucose units) were perfused in the first study. Net glucose absorption during perfusion of the partial hydrolysate and free glucose was similar, but significantly faster from maltose (p less than 0.05). Hydrolysis of the polymer fraction containing more than 10 glucose units was significantly slower (29.5 +/- 2.0% of infused load) than the lower molecular weight fraction (56.4 +/- 3.8%, p less than 0.001). As net glucose absorption from the partial hydrolysate was similar to that from glucose, despite the slow hydrolysis of the higher molecular weight fraction, it seemed likely that oligosaccharides in the more rapidly hydrolysed lower molecular weight fractions were exerting a kinetic advantage on glucose absorption. This was confirmed in a second study, where glucose absorption from a complete amylase hydrolysate consisting predominantly of maltose, maltotriose and alpha-limit dextrins, occurred significantly faster (81.8 +/- 4.8 mmol/h/25 cm) than from isocaloric free glucose (55.8 +/- 4.9 mmol/h/25 cm, p less than 0.001). Chromatograms of intestinal aspirates suggested that (1->4), but not 1->6) linked oligosaccharides liberated during luminal and brush-border hydrolysis of dietary starch conferred a kinetic advantage on glucose absorption. [ABSTRACT FROM PUBLISHER]

In a prospective controlled clinical trial, 70 patients with normal gastrointestinal function were randomised to receive either an elemental diet based on Vivonex HN or an isonitrogenous isocalorie polymeric diet based on Clinifeed 400, administered by continuous 24 hour nasogastric infusion. The two groups of patients were well matched for age, sex, diagnosis, prior starvation, duration of feeding, initial nutritional status, and metabolic status. Nitrogen losses were significantly less on the polymeric feed, despite similar intakes. Serum transferrin rose significantly (1.85 +/- 0.2 to 2.30 +/- 0.2 g/l, p less than 0.05) only in the Clinifeed group, but nutritional parameters were otherwise maintained in both groups. The incidence of diarrhoea (Vivonex, 23.5%; Clinifeed, 30.6%) was not significantly different and was attributable to antibiotics in most cases. Hypokalaemia, which occurred in nearly half the patients, was equally distributed in the two groups, but hypophosphataemia occurred more often in the Vivonex group (p less than 0.05). Liver enzyme disturbances were similar in both groups. The present findings, therefore, provide no evidence that chemically defined 'elemental' diets containing free amino acids as their nitrogen source are in any way superior to polymeric diets containing whole protein and fat when administered to patients with normal gastrointestinal function. [ABSTRACT FROM PUBLISHER]

Cerebral oedema is the commonest immediate cause of death in fulminant hepatic failure and an investigation was carried out to determine the value of monitoring intracranial pressure (ICP) and to examine the effects of ICP of dexamethasone therapy and mannitol administration. ICP values in 10 patients at the time of insertion of a subdural pressure transducer (grade IV encephalopathy) averaged 15.5 +/- SD 14.8 mmHg. Despite dexamethansone therapy, which had been started on admission, rises in ICP were subsequently observed in seven of the eight patients who died. In the two patients who survived, the highest reading were 47 and 35 mmHg. Mannitol consistently reversed or arrested ICP rises when pressure was < 60 mmHg. ICP monitoring provides additional information in the managment of patients and is essential if mannitol therapy is to be used. [ABSTRACT FROM PUBLISHER]

Because of the generally more rapid amino acid absorption and lower osmotic pressure of small peptides compared with free amino acids, it has been suggested that 'elemental' diets should contain both small peptides and free amino acids as the nitrogen source. While studying protein hydrolysates intended for use in such diets we observed surprising differences in the absorption of amino acids, water, and Na+ during jejunal perfusion of partial enzymic hydrolysates of two proteins (lactalbumin and fish) which contained high and approximately equal amounts of their constituent amino acids in the form of small peptides. Total alpha amino nitrogen (alpha NH2N) absorption from the lactalbumin hydrolysate was greater, and individual amino acid absorption more even, than from equinitrogenous solutions of the fish protein hydrolysate, or from mixture of free amino acids simulating either hydrolysate. Net water and Na+ absorption occurred during perfusion of the lactalbumin hydrolysate, whereas net water and Na+ secretion occurred during perfusion of the fish protein hydrolysate. These differences were significant (P < 0.05 or less). As the differences between the hydrolysates are so marked, we conclude that it is unwise to assume that all protein hydrolysates are equally suitable for use in patients. [ABSTRACT FROM PUBLISHER]

To compare the efficacy of two oesophageal tamponade tubes, 28 patients with endoscopically proven actively bleeding varices were randomly allocated to be intubated with either a newly available 4-lumen tube incorporating an extra lumen for oesophageal suction, or the modified 3-lumen Sengstaken tube. The patients and the nursing staff preferred using the 4-lumen tube and both aspiration pneumonias and balloon dysfunction occurred less frequently. Variceal haemorrhage was successfully controlled for the first 12 hours in most patients in the two treatment groups, although the incidence of re-bleeding at 48 hours after the tube had been deflated was high. [ABSTRACT FROM PUBLISHER]

Intestinal perfusion studies performed in man have suggested that amino acid nitrogen may be absorbed more rapidly from peptides than free amino acids. The aim of the present study was to compare the effects of the oral administration of peptides and free amino acids. Two isonitrogenous liquid test meals, one containing 50 g of a partial enzymic hydrolysate of fish protein in which approximately 80% of the nitrogen content was present as small peptides (peptide meal), and the other a mixture of free amino acids (amino acid meal) the composition and molar pattern of which simulated that of the peptide meal, were administered on separate occasions to six normal subjects intubated with a triple lumen tube. Both meals contained the reference marker polyethylene glycol. Fractional absorption of amino acid residues one and two hours after ingestion of the two meals was similar at three intestinal locations situated 120, 160, and 200 cm from the mouth of each subject, and at two hours 73·8% and 72·0% of the amino acid residues had been absorbed respectively by the time the contents of the peptide and amino acid meals reached the middle sampling port of the tube. The total sum of individual amino acid increments in plasma was significantly greater 30 minutes (p < 0·025) and one hour (p < 0·05) after ingestion of the peptide than amino acid meals. By three hours the total area under the two plasma curves was similar. Normal human subjects thus appeared to be capable of assimilating orally administered mixtures of peptides and free amino acids with equal efficiency. Secretion of fluid into the lumen of the upper small intestine, assessed by reference to dilution of the polyethylene glycol, was less after ingestion of the peptide meal. In clinical situations characterised by fluid and electrolyte malabsorption consideration might be given to using small peptides rather than free amino acids as the nitrogen source in nutritional diets. [ABSTRACT FROM PUBLISHER]

The jejunal morphological and functional response to either a gluten-free diet or corticosteroid therapy was studied in six patients with dermatitis herpetiformis. In each treatment group there were two patients with subtotal villous atrophy and one with partial villous atrophys. After treatment, in both groups, morphological improvement was seen in villous and surface cell heights, mucosal thickness, and intraepithelial lymphocyte counts. Jejunal function was assessed using the perfusion technique. Absorption of glucose from a 56 mM solution was shown to improve. Water movement from this solution was in a secretory state in four patients (two in each group) before treatment and moved into the normal absorptive range after treatment. These results further outline the similarity between the mucosal lesion of dermatitis herpetiformis and true coeliac disease. [ABSTRACT FROM PUBLISHER]

Recent reports of cytomegalovirus associated colonic and oesophageal ulceration in immunosuppressed patients infected with the human immunodeficiency virus, have focused attention on the possibility that viral infections may in some cases be the initial insult which leads in susceptible subjects to gastrointestinal ulceration. In this case report we describe how systemic primary infection with the cytomegalovirus was associated with the development of multiple gastric and duodenal erosions. [ABSTRACT FROM PUBLISHER]

We report four cases of collagenous colitis. These show the variable course of the disease and emphasise the difficulties that this involves in assessing therapy. [ABSTRACT FROM PUBLISHER]