The NutriChip project - translating technology into nutritional knowledge

Advances in food transformation have dramatically increased the diversity of products on the market and, consequently, exposed consumers to a complex spectrum of bioactive nutrients whose potential risks and benefits have mostly not been confidently demonstrated. Therefore, tools are needed to efficiently screen products for selected physiological properties before they enter the market. NutriChip is an interdisciplinary modular project funded by the Swiss programme Nano-Tera, which groups scientists from several areas of research with the aim of developing analytical strategies that will enable functional screening of foods. The project focuses on postprandial inflammatory stress, which potentially contributes to the development of chronic inflammatory diseases. The first module of the NutriChip project is composed of three in vitro biochemical steps that mimic the digestion process, intestinal absorption, and subsequent modulation of immune cells by the bioavailable nutrients. The second module is a miniaturised form of the first module (gut-on-a-chip) that integrates a microfluidic-based cell co-culture system and super-resolution imaging technologies to provide a physiologically relevant fluid flow environment and allows sensitive real-time analysis of the products screened in vitro. The third module aims at validating the in vitro screening model by assessing the nutritional properties of selected food products in humans. Because of the immunomodulatory properties of milk as well as its amenability to technological transformation, dairy products have been selected as model foods. The NutriChip project reflects the opening of food and nutrition sciences to state-of-the-art technologies, a key step in the translation of transdisciplinary knowledge into nutritional advice.     

Reproducibility of ambulatory blood pressure monitoring

OBJECTIVE: To investigate whether blood pressure monitoring is reproducible. DESIGN: Reproducibility of ambulatory blood pressure monitoring data was assessed by means of traditional and relatively new statistical methods, namely correlation coefficients, regression analysis and agreement analysis. METHODS: Ninety-one normotensive and hypertensive, uncomplicated outpatients underwent monitoring twice (mean interval 241 days). Data were analysed for reproducibility, correlation, difference and adaptation. Analyses were performed to verify the reproducibilities of the diagnosis of hypertension and of the treatment assessment. RESULTS: Ambulatory blood pressure monitoring is highly reproducible in terms of traditional statistics, but not in terms of the agreement analysis (error as high as 18 mmHg), although it performs better than does office sphygmomanometry (error as high as 38 mmHg). Reproducibility is acceptable in normotensive subjects and in patients who respond to treatment, but untreated hypertensives and those who do not respond to treatment show a worse ratio. CONCLUSION: The reproducibility of ambulatory blood pressure monitoring requires improvement. We do not know how many repeated measurements we need before diagnosing hypertension. Spontaneous variability of blood pressure interferes with blood pressure reproducibility. Diagnosis and treatment assessment in hypertension must take into account poor reproducibility.     

Carbidopa attenuation of L-DOPA emesis in dogs: evidence for a cerebral site of action outside the blood-brain barrier

L-Dopa and dopamine administered intracerebroventricularly (i.c.vent.) to dogs were approximately 50 times more potent as emetic agents than when administered i.v. The fact that dopamine, which penetrates the CNS only poorly, was more potent than L-dopa by both routes of administration, suggested a central extra-blood-brain barrier site of action for L-dopa-induced emesis. Systemically administered D,L-carbidopa, an inhibitor of aromatic amino acid decarboxylase, did not affect the emetic action of systemically administered dopamine but attenuated the emetic response to L-dopa administered both i.v. or i.c.vent. Since D,L-carbidopa does not penetrate whole brain to a significant extent it was concluded that carbidopa attenuates L-dopa-induced emesis by inhibiting the decarboxylation of L-dopa to dopamine at a CNS site lying outside the blood-brain barrier.     

Drug effects on gastric secretion and stress gastric hemorrhage in the rat

The development of a simple, rapid technic for placing drugs into the rat lateral cerebral ventricle permitted comparison of intravenous and intracerebroventricular drug administration on gastric acid secretion and cold-plus-restraint (stress) induced gastric hemorrhage. Intravenous effective dose₅₀'s (micrograms) to reduce titratable acid output in 2-hr pylorus-ligated rats were: clonidine 1.0; atropine methylbromide 1.2; atropine sulfate 2.7; chlorpromazine 20.5; imipramine 397.0; morphine 837.7; and chlordiazepoxide 3419. The intravenous ED₅₀'s for inhibition of stress-induced gastric hemorrhage were (micrograms): atropine methylbromide 64.0; atropine sulfate 902.4; clonidine >4.0; chlorpromazine >256; morphine >256; chlordiazepoxide >2048; and imipramine >256. Intracerebroventricular administration of the drugs produced a different ranking of activity for inhibition of titratable acid output (ED₅₀ in micrograms); atropine methylbromide 0.1; atropine sulfate 0.5; clonidine 3.7; morphine 5.5; chlorpromazine 99.2; chlordiazepoxide >1024; and imipramine >4096. However, the order of activity for intracerebroventricular inhibition of stress-induced gastric hemorrhage was similar to the intravenous route in that atropine methylbromide was most active, 7.8 g, followed by atropine sulfate, 54.8 g, and no ED₅₀'s were obtainable for the other drugs tested. This study indicated that central nervous system control areas for gastric secretion in the rat were located in structures bordering the cerebral ventricles but that secretion inhibiting dose of drug placed in this area did not reduce the incidence of stress-induced gastric hemorrhage.     

Expression of HLA-class II antigens and proliferative capacity in autologous mixed lymphocyte reactions of human T lymphocytes exposed in vitro to alpha-endorphin

alpha-Endorphin (aEP) inhibited the expression of HLA-Class II antigens by PHA-primed T lymphocytes and reduced mitogen-induced T-cell proliferation up to 35%. This action was time related and not naloxone sensitive. When aEP was added to autologous and allogeneic lymphocyte cultures (both of non-T/T and T/T type), it inhibited lymphocyte blastogenesis up to 40%. These findings, indicating that aEP can influence some functions of immunocompetent cells, provide evidence for the functional interrelationship between the neuroendocrine and the immune systems.     

Metergoline in the inhibition of puerperal lactation.

Seventy-eight mothers who did not want to breast-feed their newborn infants took part in a trial to assess whether metergoline could effectively suppress puerperal lactation. Metergoline 8 mg/day was given to 69 women within 24 hours after delivery and continued for five days to prevent lactation. The remaining nine women were given a course of metergoline once lactation had started. The drug was effective in both preventing and suppressing lactation. Milk secretion, engorgement, and pain were significantly reduced in women taking metergoline. Metergoline has a similar effect to bromocriptine in suppressing lactation, but its mechanism of action remains unknown.