Reduced liver injury in the interleukin-6 knockout mice by chronic carbon tetrachloride administration.

BACKGROUND: Interleukin-6 has been involved in restoration of liver function after partial hepatectomy and toxic liver injury. However, normal liver regeneration in interleukin-6 knockout mice has also been reported. The aim of this work was to investigate the effect of interleukin-6 deficiency on liver injury and its regeneration in a model of long term carbon tetrachloride (CCl4) administration. DESIGN: Serum and whole livers from wild type and interleukin-6 knockout mice treated with carbon tetrachloride (0.25 mL kg(-1)) twice a week were obtained after 4, 6 and 8 weeks (n = 4-6). Sections were assessed for liver regeneration, liver injury and hepatocyte apoptosis whereas sera were assayed for aminotransferase levels. Nuclear extracts and total liver lysates were assayed for transcription factor activation and apoptosis related proteins, respectively. RESULTS: When compared to wild type, interleukin-6 knockout mice showed reduced liver damage scores, lower aminotransferase levels and diminished apoptosis, as well as reduced nuclear factor kappa B activation. Although the level of active protein was lower, activation of signal transducer and activator of transcription 3 still takes place in knockout mice. Furthermore, liver regeneration measured by bromodeoxyuridine incorporation showed no differences between wild type and knockout animals after 6 and 8 weeks of treatment. CONCLUSIONS: Compared to the wild type mice liver regeneration after chronic treatment with carbon tetrachloride proceeds at a slower rate in interleukin-6 deficient mice. However, this low recovery rate is accompanied by a reduction not only in hepatocyte apoptosis, but also in activation of nuclear factor kappa B and liver injury.

Efficacy and safety of short-term adalimumab treatment in patients with active Crohn's disease who lost response or showed intolerance to infliximab: a prospective, open-label, multicentre trial.

BACKGROUND: The use of tumour necrosis factor antagonists has changed the therapeutic approach to Crohn's disease. AIM: To determine response and remission rates associated with the 4-week induction phase of adalimumab treatment in patients with luminal and/or fistulizing Crohn's disease, who have lost response to or become intolerant of infliximab. METHODS: In this multicentre, prospective, open-label, observational, 52-week study, 50 adults received an induction dose of adalimumab (160 mg at baseline followed by 80 mg at week 2). RESULTS: Of the 36 patients with luminal Crohn's disease, 83% achieved clinical response [> or =70-point reduction in the Crohn's Disease Activity Index (CDAI) score] and 42% achieved clinical remission (CDAI score <150) at week 4. Of the 22 patients with fistulizing disease, five (23%) experienced fistula remission (complete closure of all fistulas that were draining at baseline), and nine (41%) experienced fistula improvement (> or =50% decrease in the number of fistulas that were draining at baseline) at week 4. Of the 19 adverse events, most [13 (68%)] were mild, and no serious or infectious adverse events occurred. CONCLUSIONS: Adalimumab may be an effective alternative in patients with luminal and/or fistulizing Crohn's disease who have lost response to or become intolerant of infliximab.

Review article: the intestinal lumen as a therapeutic target in inflammatory bowel disease.

Undigested carbohydrates reaching the colon can act as competitors for epithelial bacterial receptors, making it difficult for noncommensal bacteria to adhere to them. On the contrary, fermentation of these carbohydrates by anaerobic flora produces - among other substrates - butyrate that is involved in numerous important metabolic processes. These include the provision of energy to the colonocytes, the enhancement of sodium and water absorption and the synthesis of mucus and cell membranes. In addition, butyrate inhibits the nuclear translocation of the transcription factor NFkappaB, which exerts a potent anti-inflammatory activity. Clinical experience with probiotics in inflammatory bowel disease (IBD) is controversial. Whereas some probiotic preparations appear to be useful in ulcerative colitis (UC) and pouchitis, most attempts to use probiotics for treating or preventing recurrence in Crohn's disease have failed. It should be pointed out that - unlike in the small bowel - the colon and ileal pouches are well-established microbiological ecosystems with increasing amounts of a wide variety of bacterial strains. These bacterial strains have a high degree of metabolic interaction with luminal nutrients and a greater probability of developing dysbiosis. With this in mind, the rationale for using pre- and probiotics appears to be stronger for colonic IBD (UC or Crohn's colitis) and pouchitis than for IBD mostly involving the small bowel.

Clinical evolution of luminal and perianal Crohn's disease after inducing remission with infliximab: how long should patients be treated?

BACKGROUND: Few data are available regarding the evolution of Crohn's disease after discontinuing a successful course of infliximab. AIM: To evaluate clinical outcome of Crohn's disease after induction of remission with three infliximab infusions (luminal disease) and after maintenance of remission with 1-year course of infliximab every 8 weeks (luminal and perianal). METHODS: Twenty-three patients with active luminal Crohn's disease who responded to three infusions of infliximab (0, 2, and 6 weeks), and 23 patients with sustained response to infliximab every 8 weeks during 1 year, were included. Patients were followed-up until relapse or for at least 6 months after infliximab discontinuation. Clinical outcomes and factors associated to relapse were evaluated. RESULTS: In luminal Crohn's disease, a three-infusion infliximab regimen achieved a sustained response in most patients, especially if a complete response occurred at the time of the third infusion. In patients treated for 1-year, infliximab discontinuation was also successful, with a cumulative probability of being free of relapse of 69% at 12 months. In perianal disease, early relapse was the rule after stopping infliximab treatment, with only 34% of patient maintaining remission at 1 year. CONCLUSIONS: Short regimens of infliximab might be evaluated in patients with luminal Crohn's disease. However, infliximab discontinuation is not recommended in perianal Crohn's disease, because of a high rate of early relapse.

[Autoimmune hemolytic anemia associated with ulcerative colitis]. / Anemia hemolítica autoinmunie asociada a colitis ulcerosa.

The incidence of immunological disorders has been reported to be greater in patients with inflammatory bowel disease than among the general population. The association of ulcerative colitis (UC) and autoimmune hemolytic anemia (AIHA) was first described in the early 1950s but no more than 50 cases have been described in the international literature. Detailed description of the pathogenic mechanisms involved in this association is lacking. The clinical course of AIHA and treatment response in these patients seems to be independent of UC, sometimes requiring immunosuppressive treatment and even surgery. We present 2 cases of AIHA associated with UC with distinct response to conventional treatment. We also review the literature on the subject.

[Gasometric alterations in hospitalized cirrhotic patients]. / Alteraciones gasométricas en pacientes cirróticos hospitalizados.

BACKGROUND AND OBJECTIVES: Gas exchange alterations have been described in cirrhotic patients; but by the moment, a few prospective studies have focused in them. The aim of this study was to describe the frequency and severity of gasometric alterations in hospitalized cirrhotic patients, a their correlation with hepatocellular disfunction. PATIENTS AND METHODS: 50 consecutive cirrhotic patients (41 males) admitted for liver decompensation (ascites, liver encephalopathy, alcoholic hepatitis and upper gastrointestinal bleeding) without acute or chronic cardiopulmonary disfunction were included in the study. Patients were classified according with Child-Pugh score (A, n = 13; B, n = 21; C, n = 16). Severe alcoholic hepatitis (SAH) was confirmed in 7 patients. Arterial gasometry was performed in all patients before discharge. Contrast echocardiography was performed in any case of suspicion of hepatopulmonary syndrome (HPS). RESULTS: Light hypoxemia was observed (80.9 mmHg), without differences with Child-Pugh. Hypocapnia was significantly more evident in Child C than in A and B (31.2 +/- 3.1 vs. 38.1 +/- 4.3 y 36.3 +/- 5 mmHg; p < 0,05), respectively. Cirrhotic patients with SAH showed a significantly higher hypocapnia by comparison with others (31.2 +/- 3.1 vs. a 36.3+/-5 mmHg; p < 0.05). In multivariate analysis, independent prognostic variables for hypocapnica were plasmatic levels of protrombin time, albumin and sodium. HPS was confirmed in 8 patients (16%). CONCLUSIONS: The most prevalent gas exchange abnormality in cirrhosis was the alteration of alveolar-arterial oxygen tension gradient, directly correlated with hepatocellur disfunction. Hypocapnia could be a compensatory mechanism or the result of the activation of central respiratory centres by non-depurated substances by the liver.

Factors related to the plasma fatty acid profile in healthy subjects, with special reference to antioxidant micronutrient status: a multivariate analysis.

The plasma lipid fatty acid (FA) profile was measured in 83 healthy subjects (35 men, 48 women; ages 18-82 y). The association of 19 variables (including serum antioxidant micronutrients) with saturated (SFA), monounsaturated (MUFA), essential (EFA), and polyunsaturated fatty acid (PUFA) status was assessed by stepwise multiple-linear regression. Serum selenium was directly associated with percent EFA and n-6 PUFA (r = 0.38, P = 0.0004 for both) and inversely related to percent SFA in phospholipids (r = -0.38, P = 0.0004). Serum selenium was the only predictor of the unsaturation index of this fraction (r = 0.45, P = 0.0000). Although associations of plasma FA pattern with age, serum cholesterol, bilirubin, vitamin E, and zinc were also disclosed, only for selenium did the antioxidant effect seem to explain this relationship. These results suggest that antioxidant micronutrients should be measured when PUFA metabolism is studied. The relationship between plasma FA and antioxidant micronutrients in disease states needs further research.

Determinants of plasma Fatty Acid abnormalities in patients with active inflammatory bowel disease: a multivariate analysis.

: Patients with active inflammatory bowel disease (IBD) have increased levels of n3 and decreased levels of n6 plasma long-chain polyunsaturated fatty acids (LC-PUFA). Using multivariate statistical techniques, this study assessed the influence of the potentially important factors of diagnosis (ulcerative colitis versus Crohn's disease), disease activity, malnutrition, location of disease, therapy, age, and sex on these plasma fatty acid abnormalities. Plasma fatty acids were analyzed by semicapillary column gas-liquid chromatography in 73 patients with IBD and 107 healthy controls. The effect of each confounder upon either "low" (below the first quartile of the control group) or "high" (above the third quartile of the control group) levels of each fatty acid (FA) was assessed by means of stepwise logistic regression analyses. After controlling for these factors, disease activity remained the primary factor associated with changes in the plasma FA profile. Moderate/severe activity was significantly associated with low n6 LC-PUFA and was inversely related to high n3 LC-PUFA. Corticosteroid therapy was independently associated with high C16:0 and C18:2n6 plasma values and low C20:3n6 values and unsaturation index. Sulfasalazine therapy was inversely associated with low percentages of both C18:0 and C20:3n6. Hypoalbuminemia was significantly related only to low values of C18:0. No relationship between any confounder and high levels of n3 LC-PUFA was found. The observed relationships may be of importance in the pathogenesis and treatment of IBD.

Review article: the role of nutrition in the treatment of inflammatory bowel disease.

Nutrients may be involved in the modulation of the immune response through at least three different mechanisms. First, the intestinal ecosystem plays a pivotal role in the pathogenesis of inflammatory bowel disease, triggering the uncontrolled inflammatory response in genetically predisposed individuals. Nutrients, together with bacteria, are major components of, and can therefore influence, the intestinal environment. Second, as components of cell membranes, nutrients can mediate the expression of proteins involved in the immune response, such as cytokines, adhesion molecules and nitric oxide synthase. The composition of lipids in the cell membrane is modified by dietary changes and can influence cellular responses. Indeed, various epidemiological, experimental and clinical data suggest that the immune response may be sensitive to changes in dietary composition. Finally, suboptimal levels of micronutrients are often found in both children and adults with inflammatory bowel disease, although, with the exception of iron and folate, it is unusual to discover symptoms attributable to these deficits. However, subclinical deficits may have a pathophysiological significance, as they may favour the self-perpetuation of the disease (due to defects in the mechanisms of tissue repair), cause defective defence against damage produced by oxygen free radicals and facilitate lipid peroxidation. These events can occur even in clinically inactive or mildly active disease, as well as in the development of dysplasia in the intestinal mucosa. Some dietary manipulations have been attempted as primary treatment for rheumatoid arthritis, and specially formulated diets for enteral nutrition have proved to be an effective treatment for Crohn's disease. Most trials, although lacking sufficient patient numbers, have demonstrated a role for dietary manipulation as primary therapy for inflammatory disease. Dietary lipids are one of the most active nutritional substrates modulating the immune response. Recently, it has been demonstrated that lipids may be a key factor explaining the therapeutic effect of clinical nutrition in Crohn's disease.

Azathioprine without oral ciclosporin in the long-term maintenance of remission induced by intravenous ciclosporin in severe, steroid-refractory ulcerative colitis.

BACKGROUND: Intravenous ciclosporin is considered to be the only alternative to avoid surgery in severe, steroid-refractory ulcerative colitis. In responders, some authors recommend a switch to oral ciclosporin to act as a 'bridge' until the therapeutic action of azathioprine is achieved for maintenance treatment. AIM: To report the short- and long-term outcome of intravenous ciclosporin-responsive ulcerative colitis patients treated with oral azathioprine without oral ciclosporin. METHODS: The records of all patients treated with intravenous ciclosporin for severe, steroid-refractory ulcerative colitis were reviewed. Responders following treatment with azathioprine but without oral ciclosporin as maintenance therapy were included. Patients with colonic cytomegalovirus infection and/or follow-up of less than 1 year were excluded. RESULTS: Twenty-seven patients were included. Steroids were discontinued in 24 (89%). The median follow-up was 36 months. Eighteen (75%) patients presented mild or moderate relapses, which were easily managed with salicylates or steroids. Cumulative probabilities of relapse were 42%, 72% and 77% at 1, 3 and 5 years, respectively. Eleven (40.7%) patients underwent elective colectomy. Cumulative probabilities of colectomy were 29%, 35% and 42% at 1, 3 and 5 years, respectively. No opportunistic infections were observed. CONCLUSIONS: Oral azathioprine seems to be enough to maintain long-term remission induced by intravenous ciclosporin in patients with steroid-refractory ulcerative colitis. The 'bridging step' with oral ciclosporin may not be necessary in this subset of patients, although a randomized controlled trial is warranted to confirm this hypothesis.

Granulocyteaphaeresis in steroid-dependent inflammatory bowel disease: a prospective, open, pilot study.

BACKGROUND: Uncontrolled studies suggest that granulocyteaphaeresis might be useful in the management of active ulcerative colitis. AIM: To assess the efficacy of granulocyteaphaeresis treatment in active steroid-dependent inflammatory bowel disease. METHODS: We conducted a multicentre, prospective, open, pilot study in patients with steroid-dependent inflammatory bowel disease. All patients were started on 60 mg/day of prednisone; after 1 week, a five-session programme of granulocyteaphaeresis (once per week) was started. The steroid dose was tapered weekly if there was clinical improvement. Remission was defined as an inactive clinical activity index together with complete withdrawal of steroids at week 6. The patients were followed up for at least 6 months or until disease relapse. RESULTS: Twenty-six patients (14 ulcerative colitis, 12 Crohn's disease) were included. More than a half had been previously treated with immunomodulators. Remission was achieved in 62 and 70% of ulcerative colitis and Crohn's disease, respectively. During a median follow-up of 12.6 months, six of eight ulcerative colitis patients maintained their clinical remission; however, only one Crohn's disease patient remained in remission after the first 6 months of follow-up. CONCLUSIONS: Granulocyteaphaeresis is a safe treatment option in inflammatory bowel disease. A five-session programme of granulocyteaphaeresis seems to be efficient in the treatment of steroid-dependent ulcerative colitis, but not in Crohn's disease.

Malnutrition-related polyunsaturated fatty acid changes in plasma lipid fractions of cirrhotic patients.

Cirrhotic patients have both impaired liver function and nutritional derangement. In fact, the prevalence of protein-energy malnutrition (PEM) is very high in these patients. The aim of the present study was to elucidate whether the nutritional status in cirrhosis could be an additional factor that would affect levels of plasma lipids. Plasma lipid phosphorus, cholesterol, and triglycerides (TG), and fatty acid profiles in plasma and plasma fractions were determined in 50 healthy subjects and 92 patients with liver cirrhosis. The cirrhotic patients were prospectively included in three groups according to the result of nutritional assessment: group 1 (n = 38), acceptable nutritional status (including well-nourished and mildly malnourished patients); group 2 (n = 29), moderate PEM; and group 3 (n = 25), severe PEM. The main findings of this study were that the decrease in plasma cholesterol and linoleic, dihomo-gamma-linolenic, and arachidonic acid levels of cirrhotic patients was related to the degree of PEM. Cholesteryl esters (CE) appeared to be the most sensitive indicator of lipid changes in cirrhosis. We consider that the role of malnutrition in the changes observed for polyunsaturated fatty acid (PUFA) profiles in plasma lipids of cirrhotic patients may be of major importance, since severe malnourished subjects exhibited the lowest levels of those compounds. Dietary supplementation of both essential fatty acids (EFA) and long-chain PUFA in adequate amounts to the cirrhotic patient might be of importance in the management of the disease.

The effects of fish oil, olive oil, oleic acid and linoleic acid on colorectal neoplastic processes.

BACKGROUND AND AIMS: Several nutrients play a significant role in colorectal cancer development, and fats could be among the most determinant. While several studies have shown that the n-3 fatty acids eicosapentaenoic and docosahexaenoic and its main dietary source, fish oil could exert important antineoplastic effects, much less is known about the effects of olive oil and its main fatty acid, oleic acid, and linoleic acid. The aim of these studies is to assess the role of these nutrients in crucial processes involved in colorectal carcinogenesis. METHODS: Caco-2 and HT-29 colorectal cancer cells were supplemented with different fats and their role in apoptosis induction, cell proliferation, and differentiation was studied. COX-2 and Bcl-2 expressions were also assessed. RESULTS: Supplementation with fish oil or olive oil results in an induction of apoptosis and cell differentiation. The latest effect was also induced by oleic and linoleic acid. Fish oil diminishes significantly cell proliferation. Supplementation with fish oil and olive oil results in an early downregulation of COX-2 followed by a decrease in Bcl-2 expression. CONCLUSIONS: Fish oil and olive oil are capable of influencing crucial processes responsible for colorectal cancer development. COX-2 and Bcl-2 may be important mediators of some of these effects.

Changes in mucosal fatty acid profile in inflammatorybowel disease and in experimental colitis: a common response to bowel inflammation.

BACKGROUND AND AIMS: Plasma polyunsaturated fatty acid profile in patients with inflammatory bowel disease is abnormal. We aimed to assess the mucosal fatty acid pattern in patients with ulcerative colitis and Crohn's disease, and in rats with trinitrobenzene-sulfonic acid (TNB) induced colitis. METHODS: Fatty acids were measured in colonic mucosa of patients with ulcerative colitis (n = 30), Crohn's disease (n = 21), and healthy controls (n = 13). Likewise, they were assessed in the colonic mucosa of rats with TNB- and sham-colitis. RESULTS: There was an increase of the end-products (C22:5n3, C22:6n3, C20:4n6, C22:5n6) and a decrease of the precursors (C18:3n3, C18:2n6) of both n3 and n6 polyunsaturated fatty acids in the mucosa of active ulcerative colitis and TNB-colitis. Also, high values of saturated (C16:0, C18:0) and low values of monounsaturated fatty acids (C18:1n9) were observed. Furthermore, the mucosa of active Crohn's disease showed substantial changes in saturated, monounsaturated and essential fatty acids, but not in polyunsaturated fatty acids. Mucosa of patients with inactive disease showed intermediate fatty acid values between the mucosa of active patients and healthy controls. CONCLUSIONS: Colonic inflammation causes a characteristic modification of the mucosal fatty acid profile which appears to be common to different aetiologies and seems to be related to the degree of inflammation.

Effect of L-arginine on the course of experimental colitis.

BACKGROUND AND AIMS: L-Arg is the substrate for nitric oxide, and also for L-ornithine which, in turn, is the precursor for the synthesis of collagen and polyamines. By these different metabolic pathways, L-Arg is involved in the mechanisms of inflammation, tissue repair and fibrosis. Thus, the aim of this study was to assess the effect of both different amounts of L-Arg supplementation and L-Arg-free diets upon colonic inflammatory damage and fibrosis in experimental colitis. METHODS: Sprague-Dawley rats with trinitrobenzene sulphonic acid (TNBS)-induced colitis received increasing doses of L-Arg (30, 100, 500 mg/day), or D-Arg (500 mg/day). In a second experiment, two L-Arg-free diets (one supplemented with L-Gly) were compared to a L-Arg diet. Nitrite/nitrate release in the lumen of the colon and colonic damage were evaluated. In the first experiment, tissue collagen levels and colonic mucosal proliferation were also assessed. RESULTS: In the acute phase of colitis, intracolonic nitrite/nitrate levels were significantly higher in the 100 and 500 mg supplemented L-Arg groups than in D-Arg group. However, only rats treated with 500 mg of L-Arg showed moderately higher inflammatory and fibrosis colonic scores than the D-Arg treated rats. There was no significant influence of L-Arg-free diets on the course of TNBS-induced colitis. However, L-Arg diet accelerated weight gain both pre- and post-TNBS. CONCLUSIONS: These results suggest that normal amounts of L-Arg in the diet are not harmful, whereas both absence of L-Arg or supplementation with high doses of this amino acid may be deleterious. In the former this might be due to a decrease of nitrogen retention in injured rats, whereas in the latter it may result from both nitric oxide-mediated tissue damage and collagen deposition.

Nutritional support in liver disease.

Protein-energy malnutrition is highly prevalent in patients with chronic liver disease, especially in those with advanced cirrhosis, and seems to influence their survival. Enteral and parenteral approaches to the treatment of alcoholic hepatitis have yielded controversial results. The use of polyunsaturated lecithin might be a promising alternative for the future. Enteral nutrition is the preferred way of providing artificial nutrition to patients with advanced cirrhosis. In some trials, it appears to improve the short-term survival of these patients. The long-term use of oral nutritional supplements may widen the scope of enteral nutrition in cirrhotic patients.

IOIBD questionnaire on the clinical use of azathioprine, 6-mercaptopurine, cyclosporin A and methotrexate in the treatment of inflammatory bowel diseases.

OBJECTIVE: To obtain information on the clinical experience with azathioprine (AZA), 6-mercaptopurine (6-MP), cyclosporin A (CyA) and methotrexate (MTX) in the treatment of patients with inflammatory bowel disease (IBD) by gastroenterologists and internists in different countries. DESIGN: A questionnaire designed by the International Organization for the Study of Inflammatory Bowel Disease (IOIBD) was mailed to 300 gastroenterologists, living in North America (n = 76) and Europe (n = 224) (12 countries), to obtain information on clinical experience. PARTICIPANTS: More than half of the respondents (168/298; 56.4%) worked in university hospitals and 58/298 (19.5%) in general (non-university) hospitals. Two-thirds (65%) had more than 10 years' experience in gastroenterology. RESULTS: The respondents had personal experience with AZA (88.4%), 6-MP (33.3%), CyA (48.7%) and MTX (36.3%). AZA was prescribed more frequently in Europe (92.6%) than in North America (74.2%) (P = 0.0002), 6-MP less frequently by the European than the North American respondents (23.8 and 53.3% respectively, P = 0.0001). Two-thirds (69.7%) usually prescribed AZA together with steroids to Crohn's disease patients; 62.4% of the respondents prescribed AZA for periods longer than 24 months. For ulcerative colitis, 77.9% had experience with AZA (Europe > North America, P = 0.0001). AZA had been prescribed by 69 respondents to pregnant patients, without apparent toxicity. Acute pancreatitis had been observed after AZA by 56.7% respondents; 25 malignancies were mentioned (six lymphoma, three leukaemia, three colon cancer, four renal carcinoma, nine others). CyA had been prescribed in acute ulcerative colitis by 140/291 respondents (North America 45.1%, Europe 49.1 %); of all respondents 63.9% treated < 5 patients with CyA, 36.1% 6-20 cases. CyA results were considered good in 29.5%, acceptable but with recurrences in 58.6%, and poor in 14.3%. MTX was prescribed in North America by 47.8% of the respondents, and by 33.9% in Europe (not significant). Several significant differences were observed between the prescription behaviour of respondents working at university hospitals and non-university hospitals, in particular in relation to participation in clinical trials. CONCLUSIONS: Considerable experience exists in the use of immunosuppressive therapy in IBD; however, differential prescription behaviour exists in the choice of immunosuppressives between North America and Europe. These IOIBD study results may contribute to a better insight in the daily use of immunosuppressive agents in IBD by gastroenterologists and other specialists.

Low serum selenium concentration in a healthy population resident in Catalunya: a preliminary report.

Serum selenium levels were determined in 92 healthy subjects [40 men, 52 women; mean age 33.5 +/- 1.6 (s.e.m.) years, range 16-71 years] living in the province of Barcelona, Catalunya, Spain. Only well-nourished individuals with unremarkable clinical history, normal blood chemistry and haematological tests were selected. The subjects were divided into 6 age groups for each sex. Serum samples were analysed using a modification of the standard electrothermal graphite furnace atomic absorption spectrophotometry method to shorten the procedure while maintaining its accuracy. A significant correlation (y = -1.31 + 1.51 x; r = 0.9967, P less than 0.001) was observed between our method and the standard assay method. The mean serum selenium concentration was 60.39 micrograms/l, 95 per cent CI 53.35-67.45 micrograms/l. There were age- but no sex-group differences (P less than 0.001). This result is similar to that found in countries whose low selenium levels have been related to an increased risk of some disease states. Clinical and health implications of this suboptimal selenium status are discussed.

Polyunsaturated fatty acid deficiency in liver diseases: pathophysiological and clinical significance.

Polyunsaturated fatty acid (PUFA) deficiency occurs in advanced cirrhosis and other liver diseases (acute hepatitis, cholestasis). Long-chain PUFA deficit in cirrhosis is due to both essential fatty-acid (EFA) deficiency and impaired PUFA biosynthesis. Although hepatic insufficiency itself mostly accounts for this phenomenon, other factors such as associated malnutrition also play a role. PUFA deficiency in cirrhosis probably has a wide array of both cellular and clinical consequences, but, at present, they have been difficult to prove. In addition, the route, dosage, and safety of PUFA supplementation in these patients needs extensive investigation in the future.

How effective is enteral nutrition in inducing clinical remission in active Crohn's disease? A meta-analysis of the randomized clinical trials.

BACKGROUND: The purpose of the study was to evaluate, using meta-analysis techniques, whether enteral nutrition is effective in inducing clinical remission in active Crohn's disease. METHODS: Randomized trials either comparing enteral nutrition with steroids or comparing elemental (amino acid-based) with nonelemental diets were selected using MEDLINE (1984 to 1994), reference lists from published articles, reviews, and abstracts from major gastrointestinal meetings. Sixteen studies fulfilled the inclusion criteria (four published as abstracts). Crude rates for induction of remission were collected on an intention-to-treat basis by three independent observers. Each study was given a quality score, based on predetermined criteria. RESULTS: The pooled odds ratio (OR) for all type of enteral diets compared with steroid therapy was 0.35 (95% CI, 0.23 to 0.53). This result was similar for the best studies (by quality score) combined, for trials using tube feeding combined, and when noncompliant patients were withdrawn. Further subgroup analyses were conducted on the basis of the type of diet administered. Peptide-based diets were significantly inferior to steroids (pooled OR, 0.32; CI, 0.20 to 0.52). There was a trend to lower remission rate after elemental diets than after steroids (pooled OR, 0.44; CI 0.17 to 1.12). On the other hand, pooled OR for whole protein-based diets compared with elemental diets was 1.28 (CI, 0.40 to 4.02). CONCLUSIONS: Data available to date show that steroids are better than enteral nutrition to induce remission in active Crohn's disease. These results are more evident when peptide-based diets are administered, but they are not conclusive when either elemental or whole protein-based diets are used.