Consumption of rapeseed honey leads to higher serum fructose levels compared with analogue glucose/fructose solutions.

BACKGROUND: Studies suggest that honey has less influence on serum glucose concentrations than monosaccharides and disaccharides. Previous studies, however, have only analysed glucose metabolism. METHODS: This study investigated the influence of two types of honey (rapeseed and acacia) on the serum levels of glucose, fructose, insulin and C-peptide values in healthy subjects. The results were compared with honey-comparable glucose-fructose solutions. All solutions contained 75 g of glucose and/or fructose. RESULTS: We found significantly higher fructose serum levels with rapeseed honey after 2 h but no such differences for acacia honey. C-peptide levels were significantly higher after administration of both honeys after 1 and 2 h. CONCLUSIONS: For the first time it has been found out that honey ingestion leads to a rise of blood fructose concentration: in one case, this rise was lower than that achieved after fructose/glucose controls, in the other cases it was same as after the controls. Fructose metabolism may be inhibited by unidentified substances present in the rapeseed honey. Further study to elucidate underlying mechanisms may be worthwhile, as usually there is no differentiation between the different types of honey.

Influence of cholesterol and fat in food on indirect parameters of exocrine pancreatic function.

Fecal elastase 1, chymotrypsin activity, and fat content in stool are clinical parameters of exocrine pancreatic function. The aim of this study was to clarify the possible impact of extreme changes in diet on fecal enzyme concentration/activity, since extreme diets may lead to wrong conclusions in the diagnosis of pancreatic insufficiency. Twelve healthy test persons followed 4 diet phases, each with a duration of 6 days. The 4 diet phases were (1) nearly fat-free with a low-cholesterol content; (2) high in fat and low in cholesterol; (3) high in cholesterol deriving from meat, and (4) high in cholesterol deriving from eggs. At the end of each diet phase, a 72-hour stool collection was carried out to measure fecal elastase 1, chymotrypsin and fecal fat content. The results showed no significant changes after each of the 4 diet phases. The clinical parameters of fecal elastase 1 and chymotrypsin activity in stool do not seem to be significantly influenced by fat and cholesterol deriving from food.

Short term effects of dietary medium-chain fatty acids and n-3 long-chain polyunsaturated fatty acids on the fat metabolism of healthy volunteers.

BACKGROUND: The amount and quality of dietary fatty acids can modulate the fat metabolism. OBJECTIVE: This dietary intervention is based on the different metabolic pathways of long-chain saturated fatty acids (LCFA), which are mostly stored in adipocytic triacylglycerols, medium-chain fatty acids (MCFA) which are preferentially available for hepatic mitochondrial beta-oxidation and n-3 long-chain polyunsaturated fatty acids (n-3 LCPUFA) suggested to modulate fat oxidation and storage by stimulating the peroxisomal beta-oxidation. Combined dietary MCFA and n-3 LCPUFA without LCFA may synergistically stimulate fatty acid oxidation resulting in blood lipid clearance and LCFA release from adipocytes. DESIGN: In a short term, parallel, randomized, double-blind trial effects on the fatty acid metabolism of 10 healthy volunteers (Body Mass Index 25-30) of a formula containing 72% MCFA and 22% n-3 LCPUFA without LCFA (intake: 1.500 kcal/day; fat: 55.5% of energy) were measured in comparison to an isoenergetic formula with equal fat amount and LCFA dominated lipid profile. RESULTS: The plasma triacylglycerol (p < 0.1) and cholesterol (p < 0.05) content decreased in the test group. The n-3/n-6 LCPUFA (> or = C 20) ratio increased (p < 0.0001) after 4 days treatment. The LCFA content was similar in both groups despite missing LCFA in the test formula indicating LCFA release from adipocytes into the plasma. Both groups significantly reduced body weight considerably 4 kg (p < 0.01) and fat mass up to 50% of weight loss (p < 0.05). CONCLUSION: Combined dietary 72% MCFA and 22% n-3 LCPUFA without LCFA stimulate the fatty acid oxidation and release from adipocytes without affecting any safety parameters measured.

The commercially available ELISA for pancreatic elastase 1 based on polyclonal antibodies does measure an as yet unknown antigen different from purified elastase 1. Binding studies and clinical use in patients with exocrine pancreatic insufficiency.

The measurement of fecal elastase 1 concentrations by means of an ELISA based on monoclonal antibodies (mABs) highly specific for human elastase 1 (ELISA 1) has become an accepted indirect test of the exocrine pancreatic function during the last years. Its use has been demonstrated in many clinical studies including comparison with direct function tests and ERCP morphology. Recently, a new ELISA, also named "elastase 1" based on polyclonal antibodies (pABs; ELISA 2) became available. In the present investigation we performed binding studies with purified elastase 1 as well as studies on patients with exocrine insufficiency with both ELISAs. Surprisingly, the pABs on the solid phase (catcher antibodies) of ELISA 2 did not bind purified elastase 1. These antibodies seem to react with an as yet unknown antigen associated with elastase 1. Measurement of samples from patients suspected to suffer from exocrine insufficiency showed a weak correlation of both assays but higher levels in ELISA 2, resulting in false normal results even in some patients with pancreatic steatorrhea. Since the reference range used in both assays has been established using ELISA 1, ELISA 2 must be re-evaluated in comparison to direct function tests. ELISA 2 should be renamed, since obviously it does react with an antigen (antigens) different from elastase 1.

Prospective evaluation of novel system for jejunal feeding.

BACKGROUND: Enteral nutrition should be restored immediately after trauma, acute lesion, or surgical intervention. Nutrition through nasogastric tubes is often not feasible in patients in the posttraumatic state in medical intensive care units because of recurrent episodes of gastroesophageal reflux and subsequent aspiration due to gastric paresis. Placement of nasojejunal tubes with available techniques is unreliable. METHODS: We developed a new combined catheter system for jejunal delivery and simultaneous drainage of gastric juice (Cath-in-Cath, PreOx-RS, Germany). CONCLUSION: In this article, this new tube system is presented. The safety and excellent efficacy of the novel system for enteral nutrition therapy are reported in the first series of patients worldwide.

Nutrition and cardiovascular disease.

The association between nutrition and coronary heart disease is mainly due to the effect of nutrients on serum lipids and lipoproteins. Cholesterol intake does not play a very important role for plasma cholesterol although there is a strong interindividual difference in response. The intake of saturated fatty acids strongly negatively affects plasma low-density lipoprotein cholesterol concentration while mono- and polyunsaturated fatty acids are generally regarded as beneficial. Omega-3 fatty acids mainly decrease triglyceride concentration while omega-6 polyunsaturated fatty acids mainly affect low-density lipoprotein cholesterol. Other nutrients which affect risk for coronary heart disease are dietary fiber, calcium, magnesium, iron, antioxidants as well as vitamins. Dietary fiber decrease intake of calories and fat, while iron and antioxidants play a role in oxidative modification of low-density lipoproteins. A low intake would lead to an accelerated uptake of low-density lipoprotein into the macrophage. Yet, intervention studies have not shown conclusively the benefit of a high-dose supplementation of the antioxidants vitamin E or beta-carotene on coronary heart disease. Homocysteine plasma concentration is influenced by folate as well as vitamin B6 and B12. Whether a high-dose supplementation with these substances does not only decrease plasma concentrations of homocysteine but also positively influence the course of coronary heart disease remains to be established.

Normal human serum contains a natural IgM antibody cytotoxic for human neuroblastoma cells.

Neuroblastoma (NB) is characterized by the second highest spontaneous regression of any human malignant disorder, a phenomenon that remains to be elucidated. In this study, a survey of 94 normal human adult sera revealed a considerable natural humoral cytotoxicity against human NB cell lines in approximately one-third of the tested sera of both genders. Specific cell killing by these sera was in the range of 40% to 95%. Serum cytotoxicity was dependent on an intact classical pathway of complement. By several lines of evidence, IgM antibodies were identified as the cytotoxic factor in the sera. Further analyses revealed that a 260-kDa protein was recognized by natural IgM of cytotoxic sera in Western blots of NB cell extracts. The antigen was expressed on the surface of seven human NB cell lines but not on human melanoma or other control tumor cell lines derived from kidney, pancreas, colon, bone, skeletal muscle, lymphatic system, and bone marrow. Furthermore, no reactivity was observed with normal human fibroblasts, melanocytes, and epidermal keratinocytes. The antigen was expressed in vivo as detected by immunohistochemistry in both the tumor of a NB patient and NB tumors established in nude rats from human NB cell lines. Most interestingly, the IgM anti-NB antibody was absent from the sera of 11 human NB patients with active disease. The anti-NB IgM also could not be detected in tumor tissue obtained from a NB patient. Collectively, our data suggest the existence of a natural humoral immunological tumor defense mechanism, which could account for the in vivo phenomenon of spontaneous NB tumor regression.