Laboratory evaluation of secondary causes of bone loss in Veterans with spinal cord injury and disorders.

An electronic health record (eHR) review of Veterans with a spinal cord injury and disorder (SCI/D) was conducted to understand the extent to which Veterans Affairs (VA) providers pursue workups for secondary causes of osteoporosis in this population. Laboratory tests for secondary causes were ordered in only one-third of Veterans, with secondary causes identified in two-thirds of those tested, most frequently, hypogonadism and hypovitaminosis D. PURPOSE: To identify workups for secondary causes of osteoporosis in SCI/D and the extent to which subspecialty consultations are sought. METHODS: A total of 3018 prescriptions for an osteoporosis medication (bisphosphonate, calcitonin, denosumab, raloxifene, teriparatide) among 2675 Veterans were identified in fiscal years 2005-2015 from VA administrative databases. Approximately 10% of these prescriptions were selected for eHR review. RESULTS: eHR records of 187 Veterans with a SCI/D who had received pharmacological treatment for osteoporosis were reviewed. Workups for secondary causes of osteoporosis were performed in 31.5% of Veterans (n = 59) with approximately 64.4% of those tested (n = 38) having at least one abnormality. Hypogonadism (52.0% of those tested) and hypovitaminosis D (50.0% of those tested) were the most common secondary causes of osteoporosis identified in this population. Approximately 10% of primary care and SCI providers consulted subspecialists for further evaluation and treatment of osteoporosis. Endocrinologists more frequently performed a workup for secondary causes of osteoporosis compared to other provider specialties. CONCLUSIONS: Screening for secondary causes of osteoporosis, particularly for hypogonadism and hypovitaminosis D, should be considered in patients with a SCI/D.

Actin bundles cross-linked with α-actinin studied by nanobeam X-ray diffraction.

We have performed scanning nano-beam small-angle X-ray scattering (nano-SAXS) experiments on in vitro-formed actin filaments cross-linked with [Formula: see text]-actinin. The experimental method combines a high resolution in reciprocal space with a real space resolution as given by the spot-size of the nano-focused X-ray beam, and opens up new opportunities to study local super-molecular structures of actin filaments. In this first proof-of-concept, we show that the local orientation of actin bundles formed by the cross-linking can be visualized by the X-ray darkfield maps. The filament bundles give rise to highly anisotropic diffraction patterns showing distinct streaks perpendicular to the bundle axes. Interestingly, some diffraction patterns exhibit a fine structure in the form of intensity modulations allowing for a more detailed analysis of the order within the bundles. A first empirical quantification of these modulations is included in the present work.

Insulin sensitivity in calves decreases substantially during the first 3 months of life and is unaffected by weaning or fructo-oligosaccharide supplementation.

Veal calves at the age of 4 to 6 mo often experience problems with glucose homeostasis, as indicated by postprandial hyperglycemia, hyperinsulinemia, and insulin resistance. It is not clear to what extent the ontogenetic development of calves or the feeding strategy [e.g., prolonged milk replacer (MR) feeding] contribute to this pathology. The objective of this study was therefore to analyze effects of MR feeding, weaning, and supplementation of short-chain fructo-oligosaccharides (FOS) on the development of glucose homeostasis and insulin sensitivity in calves during the first 3 mo of life. Thirty male Holstein-Friesian calves (18±0.7 d of age) were assigned to 1 of 3 dietary treatments: the control (CON) group received MR only, the FOS group received MR with the addition of short-chain FOS, and the solid feed (SF) group was progressively weaned to SF. The CON and FOS calves received an amount of MR, which gradually increased (from 400 to 1,400 g/d) during the 71-d trial period. For the SF calves, the amount of MR increased from 400 to 850 g/d at d 30, and then gradually decreased, until completely weaned to only SF at d 63. The change in whole body insulin sensitivity was assessed by intravenous glucose tolerance tests. Milk tolerance tests were performed twice to assess changes in postprandial blood glucose, insulin, and nonesterified fatty acid responses. Whole-body insulin sensitivity was high at the start (16.7±1.6×10(-4) [µU/mL](-1)), but decreased with age to 4.2±0.6×10(-4) [µU/mL](-1) at the end of the trial. The decrease in insulin sensitivity was most pronounced (~70%) between d 8 and 29 of the trial. Dietary treatments did not affect the decrease in insulin sensitivity. For CON and FOS calves, the postprandial insulin response was 3-fold higher at the end of the trial than at the start, whereas the glucose response remained similar. The SF calves, however, showed pronounced hyperglycemia and hyperinsulinemia at the end of the trial, although weaning did not affect insulin sensitivity. We conclude that whole body insulin sensitivity decreases by 75% in calves during the first 3 mo of life. Weaning or supplementation of short-chain FOS does not affect this age-related decline in insulin sensitivity. Glucose homeostasis is not affected by supplementation of short-chain FOS in young calves, whereas postprandial responses of glucose and insulin to a MR meal strongly increase after weaning.

Lactose in milk replacer can partly be replaced by glucose, fructose, or glycerol without affecting insulin sensitivity in veal calves.

Calf milk replacer (MR) contains 40 to 50% lactose. Lactose strongly fluctuates in price and alternatives are desired. Also, problems with glucose homeostasis and insulin sensitivity (i.e., high incidence of hyperglycemia and hyperinsulinemia) have been described for heavy veal calves (body weight >100 kg). Replacement of lactose by other dietary substrates can be economically attractive, and may also positively (or negatively) affect the risk of developing problems with glucose metabolism. An experiment was designed to study the effects of replacing one third of the dietary lactose by glucose, fructose, or glycerol on glucose homeostasis and insulin sensitivity in veal calves. Forty male Holstein-Friesian (body weight=114 ± 2.4 kg; age=97 ± 1.4 d) calves were fed an MR containing 462 g of lactose/kg (CON), or an MR in which 150 g of lactose/kg of MR was replaced by glucose (GLU), fructose (FRU), or glycerol (GLY). During the first 10d of the trial, all calves received CON. The CON group remained on this diet and the other groups received their experimental diets for a period of 8 wk. Measurements were conducted during the first (baseline) and last week of the trial. A frequently sampled intravenous glucose tolerance test was performed to assess insulin sensitivity and 24 h of urine was collected to measure glucose excretion. During the last week of the trial, a bolus of 1.5 g of [U-(13)C] substrates was added to their respective meals and plasma glucose, insulin, and (13)C-glucose responses were measured. Insulin sensitivity was low at the start of the trial and remained low [1.2 ± 0.1 and 1.0 ± 0.1 (mU/L)(-1) × min(-1)], and no treatment effect was noted. Glucose excretion was low at the start of the trial (3.4 ± 1.0 g/d), but increased in CON and GLU calves (26.9 ± 3.9 and 43.0 ± 10.6g/d) but not in FRU and GLY calves. Postprandial glucose was higher in GLU, lower in FRU, and similar in GLY compared with CON calves. Postprandial insulin was lower in FRU and GLY and similar in GLU compared with CON calves. Postprandial (13)C-glucose increased substantially in FRU and GLY calves, indicating that calves are able to partially convert these substrates to glucose. We concluded that replacing one third of lactose in MR by glucose, fructose, or glycerol in MR differentially influences postprandial glucose homeostasis but does not affect insulin sensitivity in veal calves.

Extant forest plantations as a potential bridge between social needs and ecological management: a comparative case study analysis.

In the face of global deforestation, there is a challenge to balance the management of areas of high conservation concern and social interests. As a response to the growing human-environment interface and the use of forests for subsistence, plantations became a management tool to provide for wood harvesting during the 1970s. Some plantations were subsequently protected from harvest as conservation of all forests increased. Plantations that are now illegal to harvest can cause local animosities toward forest protection to increase and may also result in concentrated harvesting impacts on surrounding natural forests. In this article, we analyzed case studies of plantations from El Salvador and Niger. By utilizing distinctly disparate case studies, commonalities between the two can illuminate possible management lessons. In the comparison of El Salvador and Niger forest plantations we found the following commonalities: utilizing plantations for sustainable harvest has the to potential to reduce animosity between managers and stakeholders; plantations can serve as a risk-averse testing ground for novel managerial practices; and the sustainable harvest of plantations can reduce deforestation and impacts on biodiversity in natural remnant forests. We argue that extant plantations currently under illegal harvesting legislation could become the epicenters of social and ecological conservation through a management shift to sustainable harvesting. By focusing on these relics, managers could work with stakeholders to change unduly burdening restrictions and promote cooperation between conservationists and local populations.

Hard X-ray imaging of bacterial cells: nano-diffraction and ptychographic reconstruction.

Ptychographic coherent X-ray diffractive imaging (PCDI) has been combined with nano-focus X-ray diffraction to study the structure and density distribution of unstained and unsliced bacterial cells, using a hard X-ray beam of 6.2keV photon energy, focused to about 90nm by a Fresnel zone plate lens. While PCDI provides images of the bacteria with quantitative contrast in real space with a resolution well below the beam size at the sample, spatially resolved small angle X-ray scattering using the same Fresnel zone plate (cellular nano-diffraction) provides structural information at highest resolution in reciprocal space up to 2nm(-1). We show how the real and reciprocal space approach can be used synergistically on the same sample and with the same setup. In addition, we present 3D hard X-ray imaging of unstained bacterial cells by a combination of ptychography and tomography.

The role of colonic metabolism in lactose intolerance.

Lactose maldigestion and intolerance affect a large part of the world population. The underlying factors of lactose intolerance are not fully understood. In this review, the role of colonic metabolism is discussed, i.e. fermentation of lactose by the colonic microbiota, colonic processing of the fermentation metabolites and how these processes would play a role in the pathophysiology of lactose intolerance. We suggest that the balance between the removal and production rate of osmotic-active components (lactose, and intermediate metabolites, e.g. lactate, succinate, etc.) in the colon is a key factor in the development of symptoms. The involvement of the colon may provide the basis for designing new targeted strategies for dietary and clinical management of lactose intolerance.

A curve fitting approach to estimate the extent of fermentation of indigestible carbohydrates.

BACKGROUND: Information about the extent of carbohydrate digestion and fermentation is critical to our ability to explore the metabolic effects of carbohydrate fermentation in vivo. We used cooked (13)C-labelled barley kernels, which are rich in indigestible carbohydrates, to develop a method which makes it possible to distinguish between and to assess carbohydrate digestion and fermentation. MATERIALS AND METHODS: Seventeen volunteers ingested 86 g (dry weight) of cooked naturally (13)C enriched barley kernels after an overnight fast. (13)CO(2) and H(2) in breath samples were measured every half hour for 12 h. The data of (13)CO(2) in breath before the start of the fermentation were used to fit the curve representing the digestion phase. The difference between the area under curve (AUC) of the fitted digestion curve and the AUC of the observed curve was regarded to represent the fermentation part. Different approaches were applied to determine the proportion of the (13)C-dose available for digestion and fermentation. RESULTS: Four hours after intake of barley, H(2)-excretion in breath started to rise. Within 12 h, 24-48% of the (13)C-dose was recovered as (13)CO(2), of which 18-19% was derived from colonic fermentation and the rest from digestion. By extrapolating the curve to baseline, it was estimated that eventually 24-25% of the total available (13)C in barley would be derived from colon fermentation. CONCLUSION: Curve fitting, using (13)CO(2)- and H(2)-breath data, is a feasible and non-invasive method to assess carbohydrate digestion and fermentation after consumption of (13)C enriched starchy food.

Effects of yogurt and bifidobacteria supplementation on the colonic microbiota in lactose-intolerant subjects.

AIMS: Colonic metabolism of lactose may play a role in lactose intolerance. We investigated whether a 2-week supplementation of Bifidobacterium longum (in capsules) and a yogurt enriched with Bifidobacterium animalis could modify the composition and metabolic activities of the colonic microbiota in 11 Chinese lactose-intolerant subjects. METHODS AND RESULTS: The numbers of total cells, total bacteria and the Eubacterium rectale/Clostridium coccoides group in faeces as measured with fluorescent in situ hybridization and the faecal beta-galactosidase activity increased significantly during supplementation. The number of Bifidobacterium showed a tendency to increase during and after supplementation. With PCR-denaturing gradient gel electrophoresis, in subjects in which B. animalis and B. longum were not detected before supplementation, both strains were present in faeces during supplementation, but disappeared after supplementation. The degree of lactose digestion in the small intestine and the oro-caecal transit time were not different before and after supplementation, whereas symptom scores after lactose challenge decreased after supplementation. CONCLUSIONS: The results suggest that supplementation modifies the amount and metabolic activities of the colonic microbiota and alleviates symptoms in lactose-intolerant subjects. The changes in the colonic microbiota might be among the factors modified by the supplementation which lead to the alleviation of lactose intolerance. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides evidence for the possibility of managing lactose intolerance with dietary lactose (yogurt) and probiotics via modulating the colonic microbiota.

Whole grain foods for the prevention of type 2 diabetes mellitus.

BACKGROUND: Diet as one aspect of lifestyle is thought to be one of the modifiable risk factors for the development of type 2 diabetes mellitus (T2DM). Information is needed as to which components of the diet could be protective for this disease. OBJECTIVES: To asses the effects of whole-grain foods for the prevention of T2DM. SEARCH STRATEGY: We searched CENTRAL, MEDLINE, EMBASE, CINAHL and AMED. SELECTION CRITERIA: We selected cohort studies with a minimum duration of five years that assessed the association between intake of whole-grain foods or cereal fibre and incidence of T2DM. Randomised controlled trials lasting at least six weeks were selected that assessed the effect of a diet rich in whole-grain foods compared to a diet rich in refined grain foods on T2DM and its major risk factors. DATA COLLECTION AND ANALYSIS: Two authors independently selected the studies, assessed study quality and extracted data. Data of studies were not pooled because of methodological diversity. MAIN RESULTS: One randomised controlled trial and eleven prospective cohort studies were identified. The randomised controlled trial, which was of low methodological quality, reported the change in insulin sensitivity in 12 obese hyperinsulinemic participants after six-week long interventions. Intake of whole grain foods resulted in a slight improvement of insulin sensitivity and no adverse effects. Patient satisfaction, health related quality of life, total mortality and morbidity was not reported. Four of the eleven cohort studies measured cereal fibre intake, three studies whole grain intake and two studies both. Two studies measured the change in whole grain food intake and one of them also change in cereal fibre intake. The incidence of T2DM was assessed in nine studies and changes in weight gain in two studies. The prospective studies consistently showed a reduced risk for high intake of whole grain foods (27% to 30%) or cereal fibre (28% to 37%) on the development of T2DM. AUTHORS' CONCLUSIONS: The evidence from only prospective cohort trials is considered to be too weak to be able to draw a definite conclusion about the preventive effect of whole grain foods on the development of T2DM. Properly designed long-term randomised controlled trials are needed. To facilitate this, further mechanistic research should focus on finding a set of relevant intermediate endpoints for T2DM and on identifying genetic subgroups of the population at risk that are most susceptible to dietary intervention.

Clinical neurophysiological assessment of residual motor control in post-spinal cord injury paralysis.

OBJECTIVE: This study was designed to characterize the rudimentary residual lower-limb motor control that can exist in clinically paralyzed spinal-cord-injured individuals. METHODS: Sixty-seven paralyzed spinal-cord-injured subjects were studied using surface electromyography recorded from muscles of the lower limbs and analyzed for responses to a rigidly administered protocol of reinforcement maneuvers, voluntary movement attempts, vibration, or the ability to volitionally suppress withdrawal evoked by plantar surface stimulation. RESULTS: Markers for the subclinical discomplete motor syndrome were found in 64% of the subjects. The tonic vibration response was recorded in 37%, volitional plantar surface stimulation response suppression in 27%, and reinforcement maneuver responses in 6% of the subjects. Three subjects, 4%, produced reliable but very low amplitude surface electromyography during the voluntary movement segment of the protocol. Surface electromyography recorded during passive leg movement was related to Ashworth scores as was the tonic vibration response marker (P < 0.05). CONCLUSIONS: Multimuscle surface electromyography patterns recorded during a rigidly administered protocol of motor tasks can be used to differentiate between clinically paralyzed spinal-cord-injured individuals using subclinical motor output to identify the translesional neural connections that remain available for intervention testing and treatment planning after spinal cord injury.

[Mechanical brush-catheter abrasion method for the isolation and culture of human umbilical vein endothelial cells. First in vitro results]. / Mechanische Bürsten-Katheterabrasionsmethode zur Gewinnung und Kultivierung humaner Gefässendothelzellen: Erste in vitro Ergebnisse.

UNLABELLED: Mechanical brush-catheter abrasion method for the isolation and culture of human umbilical vein endothelial cells. First in vitro results. PURPOSE: To determine the value of a nylon brush (Cragg thrombolytic catheter system) with regard to the isolation and culture of viable human vascular umbilical vein endothelial cells (HUVEC). MATERIAL AND METHODS: Fresh human umbilical cords were collected after a maximum of 6 - 8 h post delivery. They were stored in sterile tubes till further preparation. After predilation the umbilical cord veins, a 6 French brush catheter was inserted, expanded, and removed by hand using rotating movements. The nylon brush was shaken out in cell medium containing serum proteins by a connected motor drive. After repeating these procedures, the detached endothelial cells were centrifugated and resuspended. The cell numbers were assessed and cell viability controlled. RESULTS: The endothelial cell (EC) viability depended on the umbilical cord's age and was the highest (29.8 +/- 11.4 %) within 3 h after delivery. The brush abrasion (3.32 x 10(5) +/- 52016 viable EC/10 cm vein segment) enabled us to culture these cells under different cell concentrations. They grew to confluence after 2 - 3 weeks. CONCLUSIONS: The brush-catheter abrasion is an effective method for collecting viable human endothelial cells in vitro.

[First clinical results in a study of contrast enhanced magnetic resonance angiography with the 1.0 molar gadobutrol in peripheral arterial occlusive disease--comparison to intraarterial DSA]. / Erste klinische Erfahrungen zur Wertigkeit der kontrastverstärkten Magnetresonanzangiographie der Becken-Bein-Strombahn mit dem 1,0 molaren Gadobutrol--Vergleich zur i. a. DSA.

PURPOSE: To assess the value of contrast enhanced (CE)-MR angiography (MRA) with 1.0 molar Gadobutrol (Schering, Germany) in comparison to intraarterial DSA in peripheral arterial occlusive disease (PAOD). MATERIALS AND METHODS: Within 48 hours, 30 symptomatic patients with PAOD were examined by CE-MRA (Gadobutrol dose 0.2-0.3 mmol/kg body weight) and DSA. For CE-MRA, a 1.5 T magnet (Vision, Siemens, Germany) was used (FA 35 degrees, TR/TE 4.6/1.8 ms, FOV 400 mm, matrix 230 x 512, total acquisition time 81 sec). Two radiologists evaluated a total of 600 vessel segments for stenotic lesions and image quality (1 = not visible to 5 = excellent). Treatment was independently planned on the basis of the MRA and DSA findings. RESULTS: The Kendall's tau-b coefficient was 0.92 for overall stenotic grading, and 0.92, 0.93 and 0.92, respectively, for the vascular flow in the iliac, femoropopliteal and crural arteries. Sensitivity, specificity, negative and positive predictive value, and accuracy were, respectively, 94, 97, 98 and 92, 96 % for > 50 % stenoses, 95, 99, 99, 95 and 99 % for iliac arteries, 96, 98, 98%, 94 and 97 % for femoropopliteal arteries, and 92, 94, 96, 89 and 94 % for crural arteries. Therapy planning by MRA and DSA coincided in 51 of 54 cases. No relevant adverse event occurred. CONCLUSION: CE-MRA with 1.0 molar Gadobutrol is highly efficient in diagnosing peripheral arterial occlusive disease and correlates excellently with DSA.

Consistency of multi-channel surface EMG recordings: Application in spinal cord injured subjects.

We evaluated the consistency of serial polyelectromyographic recordings of altered motor control in spinal cord injured (SCI) individuals. Using 12 pairs of surface electrodes placed over major muscle groups of lower limb and trunk, we examined voluntary and involuntary and phasic and tonic features of motor control using a standardized protocol for brain motor control assessment (BMCA). The surface electromyographic (EMG) data were digitized and analysed on the basis of the root mean square (RMS) envelope of activity, with the exception of phasic tendon tap responses which were evaluated from full bandwidth EMG data. The average amplitudes of responses were calculated. The median correlation of the results from two successive examinations 1-2 weeks apart for all subjects was 0.98. Further analysis was based on ratios of corresponding elements from the two studies. Noise from null responses was suppressed by incorporating a threshold parameter T set to 1 muV(RMS). With this value, pairs of studies in 52 subjects were virtually identical (mean ratio of 1.02 +/- 0.1). Z-scores from two case studies in which pharmacological and physiological interventions changed motor control demonstrated the utility of the procedure. This method offers a reliable and appropriate means of studying altered motor control which is sensitive to changes induced after interventions.

Toward an objective interpretation of surface EMG patterns: a voluntary response index (VRI).

Individuals with incomplete spinal cord injuries (SCI) retain varying degrees of voluntary motor control. The complexity of the motor control system and the nature of the recording biophysics have inhibited efforts to develop objective measures of voluntary motor control. This paper proposes the definition and use of a voluntary response index (VRI) calculated from quantitative analysis of surface electromyographic (sEMG) data recorded during defined voluntary movement as a sensitive measure of voluntary motor control in such individuals. The VRI is comprised of two numeric values, one derived from the total muscle activity recorded for the voluntary motor task (magnitude), and the other from the sEMG distribution across the recorded muscles (similarity index (SI)). Calculated as a vector, the distribution of sEMG from the test subject is compared to the average vector calculated from sEMG recordings of the same motor task from 10 neurologically intact subjects in a protocol called brain motor control assessment (BMCA). To evaluate the stability of the VRI, a group of five healthy subjects were individually compared to the prototype, average healthy-subject vectors for all of the maneuvers. To evaluate the sensitivity of this method, the VRI was obtained from two SCI subjects participating in other research studies. One was undergoing supported treadmill ambulation training, and the other a controlled withdrawal of anti-spasticity medications. The supported treadmill training patient's VRI, calculated from pre- and post-training BMCA recordings, reflected the qualitative changes in sEMG patterns and functional improvement of motor control. The VRI of the patient followed by serial BMCA during medication withdrawal also reflected changes in the motor control as a result of changes in anti-spasticity medication. To validate this index for clinical use, serial studies using larger numbers of subjects with compromised motor control should be performed.

Altered motor control and spasticity after spinal cord injury: subjective and objective assessment.

This study of measures of spasticity, or altered motor control, compares the clinically used Ashworth scale with a method based on surface electromyographic (sEMG) recordings called brain motor control assessment (BMCA) in a group of 97 subjects with spinal cord injury (SCI) and varying levels of motor dysfunction. In this paper, we describe how sEMG-derived scores relate to the severity of spasticity as judged clinically. When sEMG data from passive movements from the BMCA were analyzed by Ashworth category, we found that when the sEMG data were averaged for a limb, there was a significant difference between scores for those with Ashworth 0 vs. 2 and 3, and 1 vs. 2 and 3 (p<0.001), but not between 0 and 1. Analysis of the individual muscle scores improved the discrimination between Ashworth categories. Superiority of sEMG data over Ashworth category as an objective quantification of altered motor control ("spasticity") is argued.

Relating clinical and neurophysiological assessment of spasticity by machine learning.

Spasticity following spinal cord injury (SCI) is most often assessed clinically using a five-point Ashworth score (AS). A more objective assessment of altered motor control may be achieved by using a comprehensive protocol based on a surface electromyographic (sEMG) activity recorded from thigh and leg muscles. However, the relationship between the clinical and neurophysiological assessments is still unknown. In this paper we employ three different classification methods to investigate this relationship. The experimental results indicate that, if the appropriate set of sEMG features is used, the neurophysiological assessment is related to clinical findings and can be used to predict the AS. A comprehensive sEMG assessment may be proven useful as an objective method of evaluating the effectiveness of various interventions and for follow-up of SCI patients.

[Nutrition and health--carbohydrates, the risks to health from the postprandial glycaemic response and the possibilities for its manipulation]. / Voeding en gezondheid--koolhydraten, het gezondheidsrisico van de postprandiale glykemische respons en de mogelijkheden voor beïnvloeding.

Carbohydrates are the most important source of food-derived energy. The metabolic effects of different types of carbohydrate can vary considerably, partially due to differences in glucose and insulin response. Several studies indicate that postprandial hyperglycaemia is associated with an increased risk of cardiovascular disease in patients with diabetes mellitus. For these patients, and possibly also for individuals with impaired glucose tolerance as well as for the healthy population at large, it may be of benefit to prevent postprandial hyperglycaemia. In order to manipulate the postprandial glycaemic response, an understanding of the underlying mechanisms of this response is crucial. The postprandial blood glucose level is influenced by a number of factors, such as the amount and type of ingested carbohydrates, gastric emptying rate and digestion and secretion of gastrointestinal and other hormones. Different approaches can be chosen to prevent postprandial hyperglycaemia, including changes in the diet and the use of drugs that delay gastric emptying or digestion of carbohydrates. The administration of gastrointestinal hormones or manipulation of the secretion of these hormones, are also possibilities. Investigating the regulation of the postprandial blood-glucose concentration and its possible manipulation could result in new approaches to preventing postprandial hyperglycaemia.

The interaction of short-chain fatty acids with adipose tissue: relevance for prevention of type 2 diabetes.

Short chain fatty acids (SCFA) are the main bacterial metabolites of colonic fermentation processes. The physiological relevance of the SCFA for the host outside the gastrointestinal tract is getting increased attention. In this review we will focus on the effect of SCFA on inflammation processes in the host in relation to insulin resistance. Obesity has been associated with a pro-inflammatory state of the adipose tissue that is associated with whole body insulin resistance leading to type 2 diabetes. Recently, two G protein-coupled receptors (GPCR) for SCFA, GPCR 41 and GPCR43, were described that are mainly expressed by immune cells but also by adipose tissue. Propionate can induce the satiety hormone leptin and reduce expression of inflammatory cytokines and chemokines indicating that SCFA have anti-inflammatory effects in human adipose tissue. In addition, in human nutritional experiments we observed that whole grain products could counteract a glucose-induced tumour necrosis factor α and interleukin-6 increase which was associated with increased plasma butyrate concentrations. This suggests that dietary fibre can produce a SCFA profile that could have anti-inflammatory effects in the body. The physiological relevance of these observations especially in relation to obesity-associated inflammation and insulin resistance is discussed.

Influence of the type of indigestible carbohydrate on plasma and urine short-chain fatty acid profiles in healthy human volunteers.

BACKGROUND/OBJECTIVES: Health effects of whole grain foods are becoming more evident. In this study, we analysed the short-chain fatty acid profiles in urine and serum derived from the colonic fermentation process of (13)C-barley meals, prepared from barley grown under (13)CO(2) atmosphere. SUBJECTS/METHODS: In a crossover study, five volunteers ingested intact barley kernels (high content of non-starch polysaccharides (NSP) and resistant starch (RS)) and barley porridge (high content of NSP only). Using a newly developed stable isotope technology, we monitored 14 and 24 h postprandially (13)C-acetate, (13)C-propionate and (13)C-butyrate in plasma and urine, respectively. The oro-cecal transit time (OCTT) of the meals was measured with the hydrogen breath test. RESULTS: The OCTT was 6 h and did not differ between the two test meals. An increase of (13)C-acetate was observed already early after ingestion of the meals (<6 h) and was attributed to early fermentation of the test meal. A rise in plasma (13)C-propionate in the fermentation phase could only be detected after the porridge and not after the kernel meal. An increase in (13)C-butyrate was only found in the fermentation phase and was higher after the barley kernels. Urine (13)C-short-chain fatty acids data were consistent with these observations. CONCLUSIONS: The difference in the profiles of (13)C-acetate, (13)C-propionate and (13)C-butyrate indicates that NSP combined with RS results in an altered fermentation profile than dietary fibre alone.