Shelf-life of prepeeled potato cultivated, stored, and processed by various methods

The present study was aimed to investigate the effects of indigestible dextrin and polydextrose, soluble dietary fibers with low molecular weight, on lipid metabolism and disaccharidase activities of intestinal mucosa in rats fed a high sucrose diet. Their effects were compared with those of well-known soluble fibers, pectin, and guar gum, and also with an insoluble fiber, cellulose. Dietary fibers added to diets at the 5% (w/w) level were alpha-cellulose, pectin, guar gum, indigestible dextrin, and polydextrose. Male Sprague-Dawley rats were given free access to test diets for 6 weeks. Body weight gain was the lowest in rats fed guar gum, the highest in rats fed cellulose, and in-between in rats fed other diets. Although guar gum, pectin, and indigestible feeding dextrin had lower plasma lipid values than cellulose feeding did, the differences were statistically insignificant. Liver triglyceride of the guar gum-fed group was about a third that of the cellulose-fed group, but although those of rats fed polydextrose, indigestible dextrin, and pectin were lower than that of cellulose, the differences were insignificant. Liver cholesterol and phospholipid concentrations were similar among groups. Daily fecal excretion of total lipid, cholesterol, and bile acids were highest in rats fed guar gum, followed by pectin-fed and cellulose-fed rats, and the lowest in rats fed indigestible dextrin and polydextrose. Jejunal sucrase activity was low in the order of guar-gum, polydextrose, indigestible dextrin, pectin, and cellulose. The results indicate that the hypolipidemic effect of soluble dietary fibers would be lessened with reduction in molecular weight, but that the lower sucrase activity by soluble fibers with low molecular weight might be beneficial for hypoglycemic effect.     

PCR analysis of microsatellite DNA markers: possibility of erroneous determination of genotypes

A comparative study of two techniques for the PCR genotyping of highly polymorphic tandem repeats was carried out by the example of a triplet repeat in the myotonin protein kinase gene. Sequencing denaturing gels were shown to yield more precise results in the analysis of amplification products.     

Research without external funding in North American psychiatry

OBJECTIVE: The authors investigated the extent and characteristics of published psychiatric research from U.S. and Canadian medical schools that was carried out without external funding. METHOD: They reviewed reports of unfunded research in 14 psychiatric journals, tabulating methodological factors and topics of study. They surveyed first authors about their academic duties and resources used in the studies. RESULTS: Unfunded studies represented 26% of research reports, were usually prospective, most commonly dealt with phenomenology/epidemiology or psychopharmacology, used low levels of technology, and were accomplished on a modest budget of time and money. CONCLUSIONS: Unfunded studies make a substantial and economically efficient contribution to psychiatric research. Future investigations should detail the institutional conditions necessary to sustain this type of research productivity.     

TNF mediates lung leak, but not neutrophil accumulation, in lungs of rats given IL-1 intratracheally

Interleukin-1 (IL-1) is increased in lung lavages obtained from patients with acute respiratory distress syndrome, and administering IL-1 intratracheally to rats causes an acute, neutrophil-dependent, oxidative lung leak. We found that rats given IL-1 intratracheally had increased lung lavage fluid tumor necrosis factor (TNF) levels, and that rats treated with TNF binding protein (TNFbp) intravenously did not develop the increased lung leak that occurs after administration of IL-1 intratracheally. In contrast, rats given IL-1 intratracheally and TNFbp intravenously had the same elevations in lung lavage neutrophil accumulation and lung lavage cytokine-induced neutrophil chemoattractant levels as rats given IL-1 intratracheally. Our results show that TNFbp decreases neutrophil-mediated lung leak, but not lung neutrophil accumulation, after administration of IL-1 intratracheally in rats.     

Mu and alpha EEG rhythms during the arrest reaction in microgravity

Mu and alpha oscillations (8–12 Hz) are the most prominent electroencephalographic rhythms observed in awake, relaxed subjects. Different cortical sources may participate in these oscillations and appear to be modulated by the sensorimotor context and functional demands. In microgravity, the marked reduction in multimodal graviceptive inputs to cortical networks participating in the representation of space could be expected to affect these spontaneous rhythms. Here, we report the results of an experiment conducted over the course of 3 space flights, in which we quantified the power of the mu and alpha rhythms in relation to the arrest reaction (i.e. in 2 distinct physiological states: eyes open and eyes closed). We observed that the power of the spontaneous mu and alpha rhythms recorded in the eyesclosed state in the sensorimotor areas (mu rhythm) and in the parieto-occipital cortex (alpha rhythm) increased in microgravity. The suppression coefficient produced by eye-opening/ closure state transition also increased in microgravity. These results are discussed in terms of current theories on the source and the physiological significance of these EEG rhythms.     

A scanning tunneling microscope that operates at high pressures and high temperatures (430 K) and during catalytic reactions

We describe the construction and operation of a scanning tunneling microscope (STM) designed in our laboratory that is contained in a reaction cell and allows operation throughout a wide range of pressures (ultra-high vacuum-atmospheric) and temperatures (300–425 K). This thermally compensated, double piezo tube design is entirely mechanically clamped. Samples are inertially translated and can be easily transferred in and out of the STM. With this microscope, we have investigated the stability of Pt(110) as a function of oxygen and hydrogen pressure and temperature.