Dietary intake of advanced glycation end products (AGEs) and changes in body weight in European adults

PURPOSE

Advanced glycation end products (AGEs) can be formed in foods by the reaction of reducing sugars with proteins, and have been shown to induce insulin resistance and obesity in experimental studies. We examined the association between dietary AGEs intake and changes in body weight in adults over an average of 5 years of follow-up.

METHODS

A total of 255,170 participants aged 25-70 years were recruited in ten European countries (1992-2000) in the PANACEA study (Physical Activity, Nutrition, Alcohol, Cessation of smoking, Eating out of home in relation to Anthropometry), a sub-cohort of the EPIC (European Prospective Investigation into Cancer and Nutrition). Body weight was measured at recruitment and self-reported between 2 and 11 years later depending on the study center. A reference database for AGEs was used containing UPLC-MS/MS-measured Nε-(carboxymethyl)-lysine (CML), Nε-(1-carboxyethyl)-lysine (CEL), and Nδ-(5-hydro-5-methyl-4-imidazolon-2-yl)-ornithine (MG-H1) in 200 common European foods. This reference database was matched to foods and decomposed recipes obtained from country-specific validated dietary questionnaires in EPIC and intake levels of CEL, CML, and MG-H1 were estimated. Associations between dietary AGEs intake and body weight change were estimated separately for each of the three AGEs using multilevel mixed linear regression models with center as random effect and dietary AGEs intake and relevant confounders as fixed effects.

RESULTS

A one-SD increment in CEL intake was associated with 0.111 kg (95% CI 0.087-0.135) additional weight gain over 5 years. The corresponding additional weight gain for CML and MG-H1 was 0.065 kg (0.041-0.089) and 0.034 kg (0.012, 0.057), respectively. The top six food groups contributing to AGEs intake, with varying proportions across the AGEs, were cereals/cereal products, meat/processed meat, cakes/biscuits, dairy, sugar and confectionary, and fish/shellfish.

CONCLUSION

In this study of European adults, higher intakes of AGEs were associated with marginally greater weight gain over an average of 5 years of follow-up.

Regulation of Amino Acid Transporters and Sensors in Response to a High protein Diet: A Randomized Controlled Trial in Elderly Men

BACKGROUND

The mammalian target of rapamycin complex 1 (mTORC1) is fundamental for many cellular processes, yet it is often dysregulated with aging. Increased amino acid (AA) availability is correlated with the expression of AA transporters (AAT) and mTORC1 activity. Although many AA sensors and mediators have been proposed to relay the AA signal to mTORC1, it has not yet been determined if chronic dietary intervention affects the expression of AAT, sensors and mediators and their relationships with mTORC1 activity.

OBJECTIVE AND DESIGN

This study investigated whether the consumption of a diet containing either the current recommended daily allowance (RDA) of protein intake (0.8 g/kg/d) or twice the RDA (2RDA) for ten weeks affected the expression of targets associated with AA transport, sensing and mTORC1 regulation in 26 older men (70-81 years).

METHOD

Muscle biopsies were collected before and after the intervention under fasting conditions. Diets were controlled by providing fully prepared meals and snacks. Western blot and quantitative polymerase chain reaction were used to measure protein and gene expression respectively.

RESULTS

Consumption of 2RDA reduced the protein expression of L-type amino acid transporter 1 (LAT1). However, plasma leucine concentration and basal mTORC1 activity were unaltered. The downregulation of LAT1 did not affect the expression of AA sensors and mediators, including leucyl tRNA synthetase (LRS), cytosolic arginine sensor for mTORC1 (CASTOR1), Sestrin2 and Rag proteins. Instead, total ribosomal protein S6 (RPS6) was upregulated with 2RDA.

CONCLUSION

Ten weeks of 2RDA diet did not affect the fasting mTORC1 signaling, but increased total RPS6 might suggest improved muscular translational capacity to maintain muscular mass.

Bilirubin scavenges chloramines and inhibits myeloperoxidase-induced protein/lipid oxidation in physiologically relevant hyperbilirubinemic serum

Hypochlorous acid (HOCl), an oxidant produced by myeloperoxidase (MPO), induces protein and lipid oxidation, which is implicated in the pathogenesis of atherosclerosis. Individuals with mildly elevated bilirubin concentrations (i.e., Gilbert syndrome; GS) are protected from atherosclerosis, cardiovascular disease, and related mortality. We aimed to investigate whether exogenous/endogenous unconjugated bilirubin (UCB), at physiological concentrations, can protect proteins/lipids from oxidation induced by reagent and enzymatically generated HOCl. Serum/plasma samples supplemented with exogenous UCB (≤250µM) were assessed for their susceptibility to HOCl and MPO/H2O2/Cl(-) oxidation, by measuring chloramine, protein carbonyl, and malondialdehyde (MDA) formation. Serum/plasma samples from hyperbilirubinemic Gunn rats and humans with GS were also exposed to MPO/H2O2/Cl(-) to: (1) validate in vitro data and (2) determine the relevance of endogenously elevated UCB in preventing protein and lipid oxidation. Exogenous UCB dose-dependently (P<0.05) inhibited HOCl and MPO/H2O2/Cl(-)-induced chloramine formation. Albumin-bound UCB efficiently and specifically (3.9-125µM; P<0.05) scavenged taurine, glycine, and N-α-acetyllysine chloramines. These results were translated into Gunn rat and GS serum/plasma, which showed significantly (P<0.01) reduced chloramine formation after MPO-induced oxidation. Protein carbonyl and MDA formation was also reduced after MPO oxidation in plasma supplemented with UCB (P<0.05; 25 and 50µM, respectively). Significant inhibition of protein and lipid oxidation was demonstrated within the physiological range of UCB, providing a hypothetical link to protection from atherosclerosis in hyperbilirubinemic individuals. These data demonstrate a novel and physiologically relevant mechanism whereby UCB could inhibit protein and lipid modification by quenching chloramines induced by MPO-induced HOCl.

L. monocytogenes in a cheese processing facility: Learning from contamination scenarios over three years of sampling

The aim of this study was to analyze the changing patterns of Listeria monocytogenes contamination in a cheese processing facility manufacturing a wide range of ready-to-eat products. Characterization of L. monocytogenes isolates included genotyping by pulsed-field gel electrophoresis (PFGE) and multi-locus sequence typing (MLST). Disinfectant-susceptibility tests and the assessment of L. monocytogenes survival in fresh cheese were also conducted. During the sampling period between 2010 and 2013, a total of 1284 environmental samples were investigated. Overall occurrence rates of Listeria spp. and L. monocytogenes were 21.9% and 19.5%, respectively. Identical L. monocytogenes genotypes were found in the food processing environment (FPE), raw materials and in products. Interventions after the sampling events changed contamination scenarios substantially. The high diversity of globally, widely distributed L. monocytogenes genotypes was reduced by identifying the major sources of contamination. Although susceptible to a broad range of disinfectants and cleaners, one dominant L. monocytogenes sequence type (ST) 5 could not be eradicated from drains and floors. Significantly, intense humidity and steam could be observed in all rooms and water residues were visible on floors due to increased cleaning strategies. This could explain the high L. monocytogenes contamination of the FPE (drains, shoes and floors) throughout the study (15.8%). The outcome of a challenge experiment in fresh cheese showed that L. monocytogenes could survive after 14days of storage at insufficient cooling temperatures (8 and 16°C). All efforts to reduce L. monocytogenes environmental contamination eventually led to a transition from dynamic to stable contamination scenarios. Consequently, implementation of systematic environmental monitoring via in-house systems should either aim for total avoidance of FPE colonization, or emphasize a first reduction of L. monocytogenes to sites where contamination of the processed product is unlikely. Drying of surfaces after cleaning is highly recommended to facilitate the L. monocytogenes eradication.

Impact of polyunsaturated vegetable oils on adiponectin levels, glycaemia and blood lipids in individuals with type 2 diabetes: a randomised, double-blind intervention study

BACKGROUND

Low adiponectin levels are discussed as risk factor for cardiovascular events. This is of special importance in individuals with type 2 diabetes (T2DM) because they are at higher risk for cardiovascular diseases. The present study aimed to investigate the effect of two plant oils rich in polyunsaturated fatty acids (PUFA), with different content of omega-3 fatty acids, on adiponectin levels, glucose and lipid metabolism in T2DM individuals treated either with insulin or oral anti-diabetics (OAD).

METHODS

Ninety-two subjects with T2DM [34 treated with insulin (T2DM-Ins) and 58 treated with OAD (T2DM-OAD)] participated in this randomised, double-blind, parallel intervention study. Individuals received either 9 g of nut oil (n-3:n-6 ratio: 1.3 : 6.1) or mixed oil (n-3:n-6 ratio: 0.6 : 5.7) per day for 10 weeks. The fatty acid profile, tocopherol, adiponectin levels and parameters regarding glucose and lipid metabolism were assessed at baseline, during and after the intervention.

RESULTS

Compliance was confirmed by significant increases in γ-tocopherol and PUFA in both oil groups. An increase in adiponectin levels in T2DM-Ins participants (+6.84% in nut oil and +4.47% in mixed oil group after 10 weeks compared to baseline) was observed, albeit not significantly different from T2DM-OAD individuals (P = 0.051). Lipid and glucose metabolism were not affected by the intervention.

CONCLUSIONS

The present study provides evidence that a small and easy change in dietary behaviour towards better fat quality moderately increases adiponectin levels in T2DM-Ins subjects, independently of the administered plant oil.

Bilirubin and beyond: a review of lipid status in Gilbert's syndrome and its relevance to cardiovascular disease protection

Gilbert's syndrome (GS) is characterized by a benign, mildly elevated bilirubin concentration in the blood. Recent reports show clear protection from cardiovascular disease in this population. Protection of lipids, proteins and other macromolecules from oxidation by bilirubin represents the most commonly accepted mechanism contributing to protection in this group. However, a recent meta-analysis estimated that bilirubin only accounts for ~34% of the cardioprotective effects within analysed studies. To reveal the additional contributing variables we have explored circulating cholesterol and triacylglycerol concentrations, which appear to be decreased in hyperbilirubinemic individuals/animals, and are accompanied by lower body mass index in highly powered studies. These results suggest that bilirubin could be responsible for the development of a lean and hypolipidemic state in GS. Here we also discuss the possible contributing mechanisms that might reduce circulating cholesterol and triacylglycerol concentrations in individuals with syndromes affecting bilirubin metabolism/excretion, which we hope will stimulate future research in the area. In summary, this article is the first review of lipid status in animal and human studies of hyperbilirubinemia and explores possible mechanisms that could contribute to lowering circulating lipid parameters and further explain cardiovascular protection in Gilbert's syndrome.

[In-vitro study on dissection of inflamed synovial tissue by hydro-jet cutting]

Surgical synovectomy is a useful therapeutic option for rheumatoid arthritis patients with ongoing active synovitis despite optimal medical therapy. The present experimental study evaluated the novel, minimally invasive surgical technique of hydro-jet cutting in vitro using synovial biopsies. Depending on the selected water pressure (30-100 bar) it is possible to achieve precise and selective dissection of the synovial membrane. It was found that application of a water jet at 60 bar for 15 s is ideal for dissecting the stratum synoviale from the stratum fibrosum without any alteration of the joint capsule. This finding was confirmed by histological analyses. This novel and precise dissection technique promises to be an excellent alternative to the established techniques of synovectomy in the near future.

Extracellular and intracellular anti-mutagenic effects of bile pigments in the Salmonella typhimurium reverse mutation assay

In vitro anti-genotoxic properties of bile pigments have been explored and confirmed recently. Despite these reports mechanisms to explain DNA protection by endogenous bile pigments remain unclear. Surprisingly, the quantification of cellular pigment absorption which could represent a fundamental prerequisite for intracellular (e.g., anti-mutagenic) effects, has not been explored. Therefore, we aimed to measure the amounts of un-/conjugated bilirubin as well as biliverdin absorbed into colonies of Salmonella typhimurium, utilising HPLC analyses, and to observe whether intracellular compound concentrations could predict anti-genotoxic effects. HPLC analyses confirmed that bacterial bile pigment absorption was concentration-dependent. Plate bile pigment concentrations were inversely associated with genotoxicity of all tested mutagens, irrespective of strain and test conditions. However, protection against frame-shift mutation in strain TA98 most strongly depended on the bacterial absorption of bilirubin and biliverdin, which indicates that bile pigments can protect by intercepting mutations extracellularly and specifically inhibit frame-shift mutations intracellularly.

Effects of unconjugated bilirubin on chromosomal damage in individuals with Gilbert's syndrome measured with the micronucleus cytome assay

Circulating unconjugated bilirubin (UCB) has been reported to protect against lung and colorectal cancer. The present study aimed to explore, for the first time, whether mildly elevated circulating UCB, as found in Gilbert`s syndrome (GS), is associated with changes of DNA damage. A random 76 individuals, matched for age and gender, were recruited from the general population and allocated into the GS group (UCB ≥ 17.1 µM; n = 38) or control group (UCB <17.1 µM; n = 38). Chromosomal and cytological changes were determined in lymphocytes and buccal cells using the cytokinesis-block micronucleus cytome assay (CBMN) and buccal micronucleus cytome assay (BMcyt). No significant differences were found between GS subjects and the control group in the CBMN and BMcyt determined endpoints. Subsequently, when age dependency of effects were analysed, lower formation of buccal micronucleated cells (by 73.3%) and buccal nuclear buds (by 70.9%) in the GS subgroup ≥ 30 years were found, compared to the GS subgroup <30 years. These findings suggest DNA protection in epithelial tissue of older individuals with GS.

Vitamin status in elderly people in relation to the use of nutritional supplements

OBJECTIVE

This study aimed to evaluate the status of several vitamins and to investigate the effect of regular individual supplementation on their status in this population.

DESIGN

An observational study.

SETTING

State of Burgenland, Austria.

PARTICIPANTS

A total of 102 non-institutionalized subjects (49% supplementing regularly, 51% without supplementation) aged between 70-90 years were recruited.

MEASUREMENTS

Plasma levels of vitamins A, D, E, K and C were determined by HPLC. The functional parameters of vitamins B1, B2 and B6, i.e. the activities of the erythrocyte enzymes transketolase, glutathione reductase and glutamic oxaloacetic transaminase, were analyzed photometrically; plasma folate and vitamin B12 were determined by RIA.

RESULTS

The status of vitamins A, E and C was generally satisfactory. Eighty-eight percent and 42% of participants were deficient in vitamins D and K, respectively, as were 29% for B6; up to 10% of participants were deficient in vitamins B1, B2, B12 and folate. A considerable percentage of participants was, however, at risk for vitamin deficiencies (vitamins B1, B6, B12, folate: 20-30%, vitamin B2: 60%). Except for vitamins A and K, regular intake of supplements had a significant positive influence on vitamin levels.

CONCLUSION

These results indicate that use of supplements significantly improved the status of several vitamins in elderly people. Due to age-related problems concerning the intake and digestion of nutrients, a moderate, regular supplementation might be a useful option for older people who are otherwise unable to satisfy their micronutrient requirements.

The status of vitamins B6, B12, folate, and of homocysteine in geriatric home residents receiving laxatives or dietary fiber

BACKGROUND

Vitamin B12 deficiency as a digestive disorder and constipation as a gastro motility disorder are common in the elderly. Laxative treatment is often chosen without regard for gut health.

OBJECTIVE

To investigate whether the addition of oat-bran to the common oral diet for 12 weeks is able to reduce constipation and laxative use and improve gut health. It is assumed that this will lead to improved plasma levels of vitamins B6, B12, folate, and of homocysteine in nursing home residents.

METHODS

A controlled, parallel intervention trial. 30 frail patients with multiple chronic diseases, aged 57-98 years, receiving laxative therapy were included. Patients were randomized into a fiber (n=15) and a control group (n=15). The intervention group received 5.2g/d oat-bran for 84 days mixed into the daily common meals. The control group received the ward's habitual diet. Food intake and laxative use were documented and blood samples (on day 01, day 42 and day 84) were collected. Vitamin B12 and folate were analyzed by radioimmunoassay, B6 and homocysteine by RP-HPLC with fluorescence detection, in addition to the routine lab test of albumin and CRP.

RESULTS

In the fiber group, the intervention was well tolerated and laxative use decreased significantly (p < 0.001). In the control group, plasma B12 decreased faster (p < 0.05). In both groups, B6 and folate status remained unchanged. Plasma homocysteine decreased in both groups (p < 0.05). General mean energy intake was low (4861.4 kJ/d).

CONCLUSION

Oat-bran helps to improve constipation management and B12 bioavailability in elderly, with multiple chronic diseases who live in nursing homes.

The anti-mutagenic properties of bile pigments

Bile pigments, including bilirubin and biliverdin, are endogenous compounds belonging to the porphyrin family of molecules. In the past, bile pigments and bilirubin in particular were thought of as useless by-products of heme catabolism that can be toxic if they accumulate. However, in the past 20 years, research probing the physiological relevance of bile pigments has been mounting, with evidence to suggest bile pigments possess significant antioxidant and anti-mutagenic properties. More specifically, bile pigments are potent peroxyl radical scavengers and inhibit the mutagenic effects of a number of classes of mutagens (polycyclic aromatic hydrocarbons, heterocyclic amines, oxidants). Coincidentally, persons with elevated circulating bilirubin concentrations have a reduced prevalence of cancer and cardio-vascular disease. Despite the encouraging in vitro anti-mutagenic effects of bile pigments, relatively little research has been conducted on their inhibitory capacity in bacterial and cultured cell assays of mutation, which might link the existing in vitro and in vivo observations. This is the first review to summarise the published data and it is our hope it will stimulate further research on these potentially preventative compounds.

Selected quality parameters of salmon and meat when fried with or without added fat

AIM

To determine whether pan-frying (pork, beef and salmon) without oil or with different fats (olive oil, corn oil or a partially hydrogenated plant oil) or steaming (only salmon) have effects on the total fat content, the fatty acid pattern, lipid peroxidation, tocopherols and in particular for salmon on vitamin D(3) and astaxanthin.

MATERIAL AND METHODS

Pork, beef patties and salmon were pan-fried (6 min each), beef fillet was pan-fried (5 min) with an additional braising period of 90 minutes and salmon was steamed for 12 minutes. Each pan-frying treatment was done with the above mentioned fats and without fat. Total fat was determined gravimetrically, the fatty acid pattern with GC, the tocopherols, astaxanthin and vitamin D(3) by using HPLC.

RESULTS

The effects on the fat quality and quantity in the final products were related to the pan-frying fat used, however, the power of the outcome was depending on the surface to volume ratio. The highest increase in total fat was observed for pork, followed by the beef patties and the braised beef. The same has been assessed for the fatty acid pattern. Tocopherols changed according to the oil used, in particular gamma-tocopherol significantly increased for each preparation after the use of corn oil. Only in pork an increase in lipid oxidation of the oil preparations has been observed. Vitamin D(3) in salmon significantly decreased after heat treatment, however a 150 g salmon portion would provide between 13.9 and 14.7 mug Vitamin D(3) which is around five times more than the average daily intake.

CONCLUSION

Pan-frying without fat can be recommended for the daily use, since the total fat intake is too high in developed countries and one main task of nutritional recommendations is to reduce the total fat intake. When pan-fried with fat, the choice of the fat is of high importance since it directly influences the quality and the flavour of the final product. In order to increase the fat quality from nutritional point of view only oils of plant or vegetable origin should be used in households. Pan-fried salmon is a good source of Vitamin D(3).

The anti-mutagenic and antioxidant effects of bile pigments in the Ames Salmonella test

The aim of this study was to explore the potential pro- and anti-mutagenic effects of endogenous bile pigments unconjugated bilirubin (BR), biliverdin (BV) and a synthetic, water soluble conjugate, bilirubin ditaurate (BRT) in the Ames Salmonella test. The bile pigments were tested over a wide concentration range (0.01-2 micromol/plate) in the presence of three bacterial strains (TA98, TA100, TA102). A variety of mutagens including benzo[alpha]pyrene (B[alpha]P), 2,4,7 trinitrofluorenone (TNFone), 2-aminofluorene (2-AF), sodium azide (NaN(3)) and tertiary-butyl hydroperoxide (t-BuOOH), were used to promote the formation of mutant revertants. Tests were conducted with (B[alpha]P, 2-AF, t-BuOOH) and without (TNFone, NaN(3), t-BuOOH) metabolic activation incorporating the addition of the microsomal liver preparation, S9. The bile pigments alone did not induce mutagenicity in any of the strains tested (p>0.05). Anti-mutagenic effects of the bile pigments were observed in the presence of all mutagens except for NaN(3) and the anti-mutagenic effects appeared independent of the strain tested. For TNFone induced genotoxicity, the order of effectiveness was BR> or =BRT>BV. However, the order was BV> or =BRT> or =BR for 2-AF. Antioxidant testing in the TA102 strain revealed bile pigments could effectively inhibit the genotoxic effect of t-BuOOH induced oxidative stress. The apparent antioxidant and anti-mutagenic behaviour of bile pigments further suggests their presence in biological systems is of possible physiological importance.

B-vitamin status and concentrations of homocysteine in Austrian omnivores, vegetarians and vegans

BACKGROUND

A vegetarian diet is considered to promote health and longevity and reduce the risk of cardiovascular diseases and cancer. However, a vegetarian diet may be deficient in some nutrients. Exclusion of animal products in vegetarian diets may affect the status of certain B-vitamins, and further cause the rise of plasma homocysteine concentration.

OBJECTIVE

The nutritional status of various B-vitamins (B(1), B(2), B(6), B(12), folic acid) and the concentration of homocysteine in blood plasma of omnivores (n = 40), vegetarians (n = 36) and vegans (n = 42) in Austria was evaluated.

METHODS

The evaluation was done using the functional parameters erythrocyte transketolase (ETK), glutathione reductase (EGR) and glutamic oxaloacetic transaminase (EGOT) activation coefficients. Enzyme activity was measured photometrically. The quantity of vitamins B(1), B(2) and B(6) in urine and the concentrations of vitamin B(6) and homocysteine in plasma were determined by HPLC methods with fluorescence detection. Plasma concentration of vitamin B(12) and folic acid were measured with radioimmunoassay.

RESULTS

Most of the subjects showed a satisfying vitamin B(1) status. Vegans presented a significantly lower mean plasma vitamin B(12) concentration than omnivores and vegetarians and deficiency in 2.4% of the volunteers but the highest mean value of plasma folate among the investigated groups. A deficient status of folate was found in 18% of omnivores and in approximately 10% of vegans and vegetarians. The status of riboflavin is considered to be deficient in about 10% of omnivores and vegetarians and in over 30% of vegans. According to the activation coefficient of GOT, approximately one third of all subjects showed vitamin B(6) deficiency. Elevated homocysteine concentration in plasma was observed in 66% of the vegans and about 45-50% of the omnivores and vegetarians. Vegan subjects had significantly higher mean plasma homocysteine levels than omnivores.

CONCLUSION

Thiamin and folate need not be a problem in a well-planned vegan diet. Vitamins B(12) and B(2) may need attention in the strict vegan diet, especially regarding elevated homocysteine levels in plasma. Pyridoxine status appeared to be independent of the diet.

Polyunsaturated Fatty Acids in the Diet and Breast Milk of Lactating Icelandic Women with Traditional Fish and Cod Liver Oil Consumption

BACKGROUND/AIMS

The proportion of polyunsaturated fatty acids (PUFA) in the diet and breast milk of lactating women with traditional fish and cod liver oil consumption was investigated under free-living conditions.

METHODS

Dietary intake of 77 lactating women was investigated by 24-hour recalls and breast milk samples were taken at the same occasions. Maternal intake data was calculated and fatty acid pattern from breast milk samples analyzed with gas chromatography.

RESULTS

Women using cod liver oil (n = 18) had a significantly higher total PUFA intake (14 +/- 10 vs. 9 +/- 7 g/day; 5.0 +/- 3.4 vs. 3.9 +/- 3.0 Energy%; p < 0.05) than women who did not use it (n = 59). In particular, mothers consuming cod liver oil had higher breast milk proportion of docosahexaenoic acid (DHA, 0.54 vs. 0.30%, p < 0.05). They also had higher breast milk proportions of eicosapentaenoic acid (EPA; 0.16 vs.0.07%; p < 0.05) and docosapentaenoic acid (DPA; 0.22 vs. 0.17%; p < 0.05).

CONCLUSION

The proportion of PUFA in the diet is significantly higher among women consuming cod liver oil. Its use also gives higher proportion of EPA,DPA and DHA in breast milk without decreasing other important fatty acids. As this may have an impact on the health and development of breast-fed infants in later life, regular maternal cod liver oil intake could be relevant for the infant as well as for the nutritional adequacy of the maternal diet.

Spectral hole burning for wideband, high-resolution radio-frequency spectrum analysis

We present experimental results for what is to our knowledge the first spectral-hole-burning based rf spectrum analyzer to cover 10 GHz of rf analysis bandwidth. The rf signal of interest is modulated onto an optical carrier, and the resultant optical sidebands are burned into the inhomogeneously broadened absorption band of a Tm3+:YAG crystal. At the same time a second, frequency-swept laser reads out the absorption profile, which is a double-sideband replica of the rf spectrum, and thus the rf spectrum can be deduced after spectral calibration of the nonlinear readout chirp. This initial demonstration shows spectral analysis covering 10 GHz of bandwidth with >5500 spectral channels and provides 43 dB of dynamic range.

Fat-soluble vitamins in the maternal diet, influence of cod liver oil supplementation and impact of the maternal diet on human milk composition

BACKGROUND/AIMS

To investigate lactating mothers' intake of fat-soluble vitamins in free-living subjects and to what extent cod liver oil supplementation influences the maternal intake in a population with common intake of cod liver oil. The impact of maternal diet on the concentration of fat-soluble vitamins in human milk was studied.

METHODS

Dietary intake of 77 lactating women was investigated by 24-hour diet recalls and breast-milk samples were taken at the same occasions. Breast milk samples were analyzed for fat-soluble vitamins.

RESULTS

The median intakes were 927 microg/day for vitamin A, 5.5 mg/day for vitamin E and 3.3 microg/day for vitamin D. Maternal vitamin A, E and D intakes were higher when the diet was supplemented with cod liver oil. Icelandic breast milk was found to have high contents of vitamin A and E. Only vitamin D was too low in breast milk to meet the recommended intake for infants. Retinylpalmitate in relation to lipids correlated with maternal vitamin A intake (r = 0.23, p < 0.05). The group with cod liver oil supplementation had significantly lower levels of gamma-tocopherol in breast milk (p < 0.01), whereas the supplementation did not affect other fat-soluble vitamins.

CONCLUSION

The recommended intake of fat-soluble vitamins for lactating women can more easily be met with a cod liver oil supplementation than diet alone. Only vitamin D in human milk cannot meet the recommended intakes for infants, with normal breastfeeding. There is a relationship between the content of vitamins A and E in human milk and the maternal diet.

Exercise and oxidative stress: significance of antioxidants with reference to inflammatory, muscular, and systemic stress

Many studies have demonstrated that intense muscular work generates considerable amounts of reactive oxygen species (ROS). In order to prevent oxidative stress, the body contains a large number of nonenzymatic and enzymatic antioxidants that either prevent ROS formation or scavenge radical species. Oxidative stress can lead to damage or destruction of cellular macromolecules such as lipids, proteins, and nucleic acids. Therefore, oxidative stress has been associated with decreased physical performance, muscular fatigue, muscle damage, and overtraining. It has been hypothesized that the body's physiological amount of antioxidants is not sufficient to prevent exercise-induced oxidative stress and that additional antioxidants are needed to reduce oxidative stress, muscular damage, or overshooting inflammation. However, some but not all investigations have demonstrated oxidative stress following physical exercise, and also, findings concerning the role of antioxidants in reducing oxidative stress are equivocal. In addition, a clear association between the amount of exercise-induced muscular, metabolic, hormonal, or inflammatory stress and levels of antioxidant vitamins could not be established consistently. Therefore, although the theoretical background may be sound, there is no scientific evidence to recommend increased quantities of antioxidants to physically active people exceeding the amount provided by a healthy, balanced nutrition.

Antioxidative power of plant oils in humans: the influence of alpha- and gamma-tocopherol

BACKGROUND

The daily diet is usually comprised of a varying antioxidant and fatty acid content acquired from plant oils. The present study was performed to evaluate the antioxidative effects of a plant oil mixture rich in alpha-tocopherol (olive/sunflower oil) in comparison with a single gamma-tocopherol-rich corn oil used in a normal, balanced human diet.

METHODS

In the context of a double-blind study 28 healthy nonsmoking male volunteers aged between 19 and 31 years were investigated. After 2 weeks of adjustment on a mixed, balanced diet (average 11.6 MJ, average fat intake approximately 105 g/day), a 2-week test period with a diet of 80 g corn oil (CO)/day vs. a mixture of 68 g olive and 12 g sunflower oil/day (MO; total 80 g) as the main fat source, was followed by a crossover after 2 weeks. Blood samples were collected at the beginning of the study and at 2-week intervals.

RESULTS

The main carriers of tocopherol in blood are low-density lipoproteins (LDLs). A highly significant correlation (r2 = 0.73, p < 0.001) was found between plasma and LDL gamma-tocopherol concentrations in the CO group, and a significant correlation was found between plasma and LDL alpha-tocopherol concentrations only in the MO group. Plasma and LDL total antioxidative capacity values could only be improved insignificantly in both groups to comparable extents, although the MO group had a twofold higher alpha-tocopherol equivalent/diene equivalent ratio (1.13 mg/g) than the CO group (0.55 mg/g).

CONCLUSION

In spite of the higher P/S ratio (CO 4.2 vs. MO 1.2) and lower alpha-tocopherol equivalent/diene equivalent ratio, the antioxidant potential of CO in vivo (total antioxidative capacity in plasma and LDL) was as efficient as the MO. This positive finding might be explained by a synergism between alpha- and gamma-tocopherol in the CO diet.

Impact of diets containing corn oil or olive/sunflower oil mixture on the human plasma and lipoprotein lipid metabolism

BACKGROUND

The effects of monounsaturated fatty acids (MUFA) rich diets compared to those that are rich in polyunsaturated fatty acids (PUFA) as well as the effects of an intake of single oils compared to oil mixtures are controversially discussed and results are contradictory.

AIM OF THIS STUDY

To evaluate the effects of a plant oil-mixture (olive/sunflower oil; saturated/monounsaturated/polyunsaturated (S/M/P) = 14:69:17) high in oleic acid but also showing a moderate content of polyunsaturated fatty acids (PUFA) in comparison with a single, PUFA rich corn oil (S/M/P = 13:33:54) used in a normal, balanced diet on human plasma and lipoprotein metabolism.

METHODS

The double-blind designed study comprised 28 healthy, non-smoking young men aged between 19 and 31 years. After two weeks of adjustment (mixed, balanced diet: 11.6 MJ average, average fat intake approximately 105 g/d), the design included a two week test period in which a diet with 80 g corn oil/d vs a mixture of 68 g olive- and 12 g sunflower oil/d (total 80 g) as the main fat source was given, followed by a crossover after two weeks. Compliance and ingestion of diets were monitored by assessing the fatty acid pattern in LDL and by determination of alpha- and gamma-tocopherol in plasma and LDL. Results Diets were well incorporated due to the significant changes in plasma- and LDL-tocopherol levels and the significant different average ratio of oleic acid to linoleic acid in LDL. The PUFA-rich corn oil diet was able to reduce low density lipoprotein (LDL) cholesterol from adjustment to T2 significantly (p < 0.01), which was also confirmed by a trend after cross over (p=0.15). Total cholesterol (only after cross over at T3), total triglycerides (TG) and very low density lipoprotein (VLDL)-TG were significantly lower at T2 after the corn oil diet than after the mixed oil diet. Total high density lipoproteins (HDL) and HDL cholesterol remained unchanged by both diets.

CONCLUSIONS

The results show that during the intervention of two weeks for each diet and the following cross over the corn oil diet had more influence on lipoprotein metabolism than the MUFA-rich diet. The hypocholesteremic effect of the PUFA-rich diet must also be connected with the high amount of unsaponifiable substances, mainly phytosterols in the corn oil.

Variable-time-delay optical coherent transient signal processing

A technique is proposed and experimentally demonstrated that achieves simultaneous optical pattern waveform storage and programmable time delay for continuous real-time signal processing by use of optical coherent transient technology. We achieve variable-time-delay and broadband signal processing by frequency shifting of two chirped programming pulses, the chirp rate of one being twice that of the other, without using brief reference pulses and without changing the timing of the programming sequence. We demonstrate the technique experimentally in Tm(3+): YAG at 5 K for 40-MHz chirps by performing temporal signal convolution with true-time delays that vary over a 250-ns range.

Optical smart-pixel-based Clos crossbar switch

We present the design of an optically interconnected Clos crossbar switch that uses three smart-pixel devices. This optical Clos architecture is also well matched to a space-wavelength switch that arbitrarily permutes data streams between wavelength-division multiplexed channels on an array of fibers. We have designed a hybrid complementary metal-oxide semiconductor-self-electro-optic device (CMOS-SEED) crossbar smart-pixel array for use in a 16-channel optical Clos switch. The crossbar devices also have an 8 x 8 array of multiple-quantum-well diodes that can be configured electrically as modulators with eight bit planes of randomly addressable local memory or as receivers with adjustable gain and threshold. We show that the current hybrid-SEED technology should support a 1024-channel Clos switch operating at 500 Mbits/s per channel if pixel power consumption can be reduced.

Wide angular aperture holograms in photorefractive crystals by the use of orthogonally polarized write and read beams

We demonstrate a method of simultaneous holographic recording and readout in photorefractive crystals that provides high write-read beam isolation and wide angular bandwidth. The method uses orthogonally polarized read and write beams and parallel tangent diffraction geometry near the equal curvature condition to provide spatially separable, orthogonally polarized diffracted output beams with high isolation and wide Bragg-matched angular bandwidth. The available angular bandwidth of this read-write technique is analyzed, simulated, and experimentally investigated. The measured angular bandwidth internal to the crystal is approximately 18° × 6° for our 45°-cut BaTiO(3) crystal, yet the entire hologram still demonstrates high Bragg selectivity. In contrast, traditional nonparallel-tangent geometries yield angular apertures of the order of 1° × 4°.

Real-time joint transform correlation with photoanisotropic dye-polymer films

The results of joint transform correlation with photoanisotropic organic materials are presented. The materials' dynamic holographic recording capability and high resolution permit the operation of such a correlator in real time. Both theoretical and experimental results show that the photoanisotropic properties cause a dependence of the correlation output on the state of the polarization of the readout beam and can be used to produce an output polarization orthogonal to the input, which permits polarization filtering to be used, greatly increasing the signal-to-noise ratio. The effect of the saturation of the nonlinearity on correlation performance is investigated and is shown to be able to improve correlator recognition and discrimination. The correlation results of binary images and of a highresolution synthetic-aperture radar image are presented, demonstrating excellent optical quality, nonlinear edge enhancement, and real-time operation.

Nontufted incisional slit grafting

BACKGROUND

The nontufted incisional slit grafting method described here is a decisively modified technique in the field of hair transplantation.

OBJECTIVE

Traditional techniques of incisional slit grafting have the risk to produce a tufted look due to compression from the sides when the grafts are placed in the incision.

METHODS AND RESULTS

Our specific method of dissection of the donor hair creates very small flat grafts that are the same shape as the recipient sites and includes trimming the epidermis and a part of the dermis. The advantage of this technique is that there is no compression on the grafts and thus it results in a diminished tufted look.

CONCLUSION

With this technique it is possible to transplant more than 2000 grafts in one session, meaning that patients with extreme baldness and a relatively small fringe of hair can become hairy in an aesthetically pleasing way due to the extremely economic redistribution of the donor hair.

[Differentiation of allotments for occupationally necessary and hygiene relevant costs of air technology designs for operating rooms]

The aeration of operation theatres serves multiple purposes. It is necessary for the regulation of room temperature (waste heat generated by the operation team and technical appliances), air exchange for oxygen supply, removal of narcotic gases and of smells (occupational limit values) as well the elimination of germs and particles emitted during operations by staff and from instruments (avoidance of germ transfer by air). This paper tries on the one hand to estimate the investment and running costs of different indoor air supplies according to the specifications given by DIN 1946, parts 2 and 4) and on the other hand to differentiate the hygienically relevant expenses of turbulent and laminar flow air supply systems. It can be seen that, due to the high heat production generated during operations, no cost can be saved through decreases in air flow volume. Depending on the operation frequency (e.g. 4 operations daily, 200-300 days per year) a hygienically relevant cost of DM 2.8-6.7 per patient is calculated for laminar flow supplies and DM 4.5-6.7 per patient for the turbulent air supply systems ("Stützstrahl"). Thus laminar flow systems are also cost-saving in comparison to turbulent air supply systems in addition to their significant technical and hygienic advantages.

Photoanisotropic incoherent-to-coherent optical conversion

A new approach to incoherent-to-coherent optical conversion based on a real-time five-wave-mixing technique in photoanisotropic organic film is presented. A uniform grating is written holographically in the sample and then erased locally by an incident white-light image. Subsequent coherent diffraction of the spatially modulated grating imposes the incoherent image upon the reading laser beam, permitting subsequent coherent optical processing. A theoretical analysis of the holographic recording and erasing mechanism in these photoanisotropic materials is presented, and the saturation is shown to be responsible for the grating intermodulation that produces the incoherent-to-coherent conversion. Experimental results of white-light images converted to inverted coherent images in real time are presented, and the resolution is shown to exceed 28 line pairs/mm.

[Serum endotoxin level in the course of open peritonitis treatment]

In 27 patients with severe diffuse purulent or fecal peritonitis planned relaparotomies with peritoneal lavage or continuous dorsoventral lavage with open abdomen were performed after surgical treatment of the primary infection. During the course of the lavage treatment serum endotoxin was measured daily. The endotoxin-induced liberation of lysosomal proteases was studied by determining the elastase from polymorphonuclear leucocytes. 16 surviving patients showed decreasing endotoxin levels and decreasing elastase concentrations during the course of abdominal lavages. Planned peritoneal lavage and continuous dorso-ventral lavage seem to have the same potency in eliminating endotoxin from the infected peritoneal cavity. In letal courses endotoxinemia either persisted at high levels or even progressed inspite of lavage treatment.