Isolation of single cells for protein therapeutics using microwell selection and Surface Plasmon Resonance imaging.

Here the feasibility is demonstrated that by combining Surface Plasmon Resonance Imaging (SPRi) and self-sorting microwell technology product secretion of individual cells can be monitored. Additionally isolation of the selected cells can be performed by punching the cells from the microwells using coordinates of the positions of microwells obtained with SPRi. Cells of interest can be retrieved sterile from the microwell array for further cultivation.

Accelerated post-glucose glycaemia and altered alliesthesia-test in Seasonal Affective Disorder.

BACKGROUND: Little is known about the link between mood, food and metabolic function in Seasonal Affective Disorder (SAD). METHODS: We investigated this link in a combined glucose tolerance-alliesthesia test in eight SAD patients in winter before and after one week light therapy, and in summer. RESULTS: SAD patients exhibited faster post-glucose glycaemic and insulin responses (p <0.05), and increased hedonic ratings of high concentrated sucrose solutions (p <0.035) when depressed in winter than when euthymic (one week after light treatment or in summer). CONCLUSIONS: The rapid glycaemic and insulin responses to an oral glucose load may be a result of accelerated gastric emptying. LIMITATIONS: The number of studied patients was rather small and no control group was studied in parallel. CLINICAL RELEVANCE: the more rapid post-glucose glycaemia may impair glucose homeostasis in depressed SAD patients.

Measurement of gastric emptying during and between meal intake in free-feeding Lewis rats.

A new scintigraphic measurement technique is described that allows accurate assessment of gastric emptying in between as well as during a number of successive meals. Measurements were made every minute of food intake, gastric nutrient filling, and gastric emptying over a 6 h, 40 min period in conscious, free-feeding, loosely restrained rats. Before receiving access to the food, the animals had been deprived for a period of 31 h. Over the full duration of the experiment, an average rate of gastric emptying of 2.46 +/- 0.18 (SE) kcal/h was established. During most meals, however, the gastric emptying rate was increased so that an average of 26.9 +/- 2.7% of the ingested calories was emptied while the animals were feeding, with an average emptying rate of 0.15 +/- 0.014 kcal/min or 8.88 +/- 0.84 kcal/h. This transient increase in the rate of gastric emptying was followed by a subsequent slowing of gastric emptying after meal termination; in the 10-min postmeal interval, an average emptying rate of 0.96 +/- 0.12 kcal/h was found. Despite these fluctuations during and immediately after meals, a relatively constant rate of caloric emptying is maintained over longer periods. There were no differences between the emptying rate during the first meal when the gastrointestinal tract was still empty, compared with later meals when the gastrointestinal tract had been filled with food. The emptying rate during the 10-min postmeal interval, however, was significantly reduced during later meals. The results suggest that gastric emptying is controlled by different mechanisms during and after the ingestion of food and that these mechanisms remain in effect at various degrees of gastrointestinal filling.

Psychological and metabolic effects of dietary carbohydrates and dexfenfluramine during a low-energy diet in obese women.

Dietary carbohydrates and dexfenfluramine (dF) have been shown to influence serotoninergic neurotransmission. To assess their effect on spontaneous physical activity, mood, sleep quality, and resting metabolic rate (RMR), 32 obese females were studied while consuming diets providing 3970 kJ (950 kcal)/d. They were randomly allocated to either a diet relatively high in carbohydrates (carbohydrate:fat:protein, 49%:22%:29% of energy intake; group 1) or to a diet relatively high in fat (carbohydrate:fat:protein, 12%:59%:29%); subjects receiving the latter diet were treated additionally with either 30 mg dF (group 2) or placebo (group 3) daily in a double-blind fashion. Spontaneous physical activity decreased in the group treated with dF compared with the other two groups (P = 0.0002). Daily self-rated questionnaires indicated that mood and tiredness were negatively affected in two groups after the first week. Subjects treated with dF lost more weight than did those in the other two groups (P = 0.013). This occurred despite a decrease in physical activity and unchanged energy intake and resting energy expenditure.

Comparison of light treatment with citalopram in winter depression: a longitudinal single case study.

A woman with seasonal affective disorder (SAD) remitted within a week in each of six separate trials of light therapy. She remitted within 2 weeks of initiating citalopram treatment. Light treatment in the morning advanced and improved sleep, whereas citalopram delayed sleep and induced intermittent awakenings. These opposite patterns suggest that sleep deprivation or sleep shifts were not crucial for eliciting therapeutic response. Light and citalopram both selectively reduced intake of sweet carbohydrate parallel with improvement, implicating CNS serotonergic mechanisms in the interaction of mood and food in winter.