[Seasonal fluctuations and influence of nutrition on macular pigment density]

PURPOSE: We have previously reported on measuring macular pigment density (MPD) with a scanning laser ophthalmoscope (HRA, Heidelberg Engineering, Heidelberg, Germany). This study war undertaken to evaluate the variation of MPD over a period of 1 year in healthy subjects. METHOD: We used autofluorescence images recorded with a HRA to evaluate MPD with a 2 degrees circle centered on the fovea. Healthy subjects were included in the study and MPD measurements were repeated every 2 months over a period of 1 year. RESULTS: We included a total of 30 healthy subjects aged 19-34 years (mean: 23+/-2 years). Mean MPD at time point 1 was 0.215+/-0.056 density units (DU), at time point 2 0.235+/-0.051 DU, at time point 3 0.218+/-0.055 DU, at time point 4 0.228+/-0.057 DU, at time point 5 0.225+/-0.053 DU, and at time point 6 0.203+/-0.050 DU. The statistical analysis revealed no significant variation of MPD over the follow-up period of 1 year. CONCLUSION: This study demonstrates that MPD shows no variation over a period of 1 year in healthy subjects.

Reduced incidence of insect-bite hypersensitivity in Icelandic horses is associated with a down-regulation of interleukin-4 by interleukin-10 and transforming growth factor-beta1

Insect bite hypersensitivity (IBH) is an allergic dermatitis of horses caused by IgE-mediated reactions to bites of insects of the genus Culicoides. IBH does not occur in Iceland due to the absence of Culicoides. However, Icelandic horses exported to mainland Europe as adults (1st generation) have a >/=50% incidence of developing IBH. In contrast, their progeny (2nd generation) has a <10% incidence of IBH. Here we show that peripheral blood mononuclear cells (PBMC) from Icelandic horses born in mainland Europe and belonging either to the IBH or healthy subgroup produce less interleukin (IL)-4 after polyclonal or allergen-specific stimulation when compared with counterparts from horses born in Iceland. We examined a role of IL-10 and transforming growth factor (TGF)-beta1 in down-regulation of IL-4 in healthy 2nd generation Icelandic horses. Supernatants of PBMC from 2nd generation healthy horses down-regulated the proportion of IL-4-producing cells and IL-4 production in stimulated cultures of PBMC from 1st generation IBH. This inhibition was mimicked by a combination of IL-10 and TGF-beta1 but not by the single cytokines. Cultures of stimulated PBMC of healthy 2nd generation horses produced a low level of IL-4, but IL-4 production was increased by anti-equine IL-10 and anti-human TGF-beta1. This shows for the first time that in horses, IL-10 and TGF-beta1 combined regulate IL-4 production in vitro. It is suggested that in this naturally occurring IgE-mediated allergy, IL-10 and TGF-beta1 have a role in the down-regulation of IL-4-induced allergen-specific Th2 cells, thereby reducing the incidence of IBH.

Nutrition in clinical practice-the refeeding syndrome: illustrative cases and guidelines for prevention and treatment

The refeeding syndrome is a potentially lethal complication of refeeding in patients who are severely malnourished from whatever cause. Too rapid refeeding, particularly with carbohydrate may precipitate a number of metabolic and pathophysiological complications, which may adversely affect the cardiac, respiratory, haematological, hepatic and neuromuscular systems leading to clinical complications and even death. We aimed to review the development of the refeeding syndrome in a variety of situations and, from this and the literature, devise guidelines to prevent and treat the condition. We report seven cases illustrating different aspects of the refeeding syndrome and the measures used to treat it. The specific complications encountered, their physiological mechanisms, identification of patients at risk, and prevention and treatment are discussed. Each case developed one or more of the features of the refeeding syndrome including deficiencies and low plasma levels of potassium, phosphate, magnesium and thiamine combined with salt and water retention. These responded to specific interventions. In most cases, these abnormalities could have been anticipated and prevented. The main features of the refeeding syndrome are described with a protocol to anticipate, prevent and treat the condition in adults.

Nutrition with 'light and water'? In strict isolation for 10 days without food - a critical case study

In her book 'Living on Light', Jasmuheen tries to animate people worldwide to follow her drastic nutrition rules in order to boost their quality of life. Several deaths have been reported as a fatal consequence. A doctor of chemistry who believably claimed to have been 'living on light' for 2 years, except for the daily intake of up to 1.5 l of fluid containing no or almost no calories was interested in a scientific study on this phenomenon. PARTICIPANT AND METHODS: The 54-year-old man was subjected to a rigorous 10-day isolation study with complete absence of nutrition. During the study he obtained an unlimited amount of tea and mineral water but had no caloric intake. Parameters to monitor his metabolic and psychological state and vital parameters were measured regularly and the safety of the individual was ensured throughout the study. The subject agreed on these terms and the study was approved by the local ethics committee.

Role of nutrition in liver transplantation for end-stage chronic liver disease

Patients with end-stage liver disease often reveal significant protein-energy malnutrition, which may deteriorate after listing for transplantation. Since malnutrition affects post-transplant survival, precise assessment must be an integral part of pre- and post-surgical management. While there is wide agreement that aggressive treatment of nutritional deficiencies is required, strong scientific evidence supporting nutritional therapy is sparse. In practice, oral nutritional supplements are preferred over parenteral nutrition, but enteral tube feeding may be necessary to maintain adequate calorie intake. Protein restriction should be avoided and administration of branched-chain amino acids may help yield a sufficient protein supply. Specific problems such as micronutrient deficiency, fluid balance, cholestasis, encephalopathy, and comorbid conditions need attention in order to optimize patient outcome.