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1.
Food Microbiol ; 37: 44-50, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24230472

ABSTRACT

This study determined exopolysaccharide (EPS) production by Weissella cibaria MG1 in sourdoughs prepared from gluten-free flours (buckwheat, oat, quinoa and teff), as well as wheat flour. Sourdoughs (SD) were fermented without sucrose, or by replacing 10% flour with sucrose to support EPS production. The amount of EPS depended on the substrate: high amounts of EPS corresponding to low amounts of oligosaccharides were found in buckwheat (4.2 g EPS/kg SD) and quinoa sourdoughs (3.2 g EPS/kg SD); in contrast, no EPS but panose-series oligosaccharides (PSO) were detected in wheat sourdoughs. Organic acid production, carbohydrates and rheological changes during fermentation were compared to the EPS negative control without added sucrose. Corresponding to the higher mineral content of the flours, sourdoughs from quinoa, teff and buckwheat had higher buffering capacity than wheat. Fermentable carbohydrates in buckwheat, teff and quinoa flours promoted W. cibaria growth; indicating why W. cibaria failed to grow in oat sourdoughs. Endogenous proteolytic activity was highest in quinoa flour; α-amylase activity was highest in wheat and teff flours. Protein degradation during fermentation was most extensive in quinoa and teff SD reducing protein peaks 18-29, 30-41 and 43-55 kDa extensively. Rheological analyses revealed decreased dough strength (AF) after fermentation, especially in sucrose-supplemented buckwheat sourdoughs correlating with amounts of EPS. High EPS production correlated with high protein, fermentable sugars (glucose, maltose, fructose), and mineral contents in quinoa flour. In conclusion, W. cibaria MG1 is a suitable starter culture for sourdough fermentation of buckwheat, quinoa and teff flour.


Subject(s)
Bread/microbiology , Edible Grain/microbiology , Food Microbiology/methods , Polysaccharides, Bacterial/metabolism , Weissella/metabolism , Bread/analysis , Edible Grain/chemistry , Fermentation , Flour/analysis , Flour/microbiology , Polysaccharides, Bacterial/chemistry , Weissella/chemistry , Weissella/growth & development
2.
J Appl Microbiol ; 115(6): 1379-87, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23957391

ABSTRACT

AIMS: The growing interest of governments and industry in developing healthy and natural alternative foods and beverages that will fulfil the consumer drive towards a healthy lifestyle and clean-label, natural diet has led to an increase in traditional lactic acid bacteria fermentation research. In particular, this research aims to address the organoleptic modulation of beverages using in situ-produced bacterial polysaccharides. METHODS AND RESULTS: Weissella cibaria MG1 is capable of producing exopolysaccharides (dextran) and oligosaccharides (glucooligosaccharides) during sucrose-supplemented barley-malt-derived wort fermentation. Up to 36·4 g l(-1) of dextran was produced in an optimized system, which improved the rheological profile of the resulting fermentate. Additionally, small amounts of organic acids were formed, and ethanol remained below 0·5% (v/v), the threshold volume for a potential health claim designation. CONCLUSIONS: The results suggest that the cereal fermentate produced by W. cibaria MG1 could be potentially used for the production of a range of novel, nutritious and functional beverages. SIGNIFICANCE AND IMPACT OF THE STUDY: Using conventional raw materials and traditional processes, novel LAB-fermented beverages can be produced representing an innovative mechanism towards fulfilling the aim to decrease government and personal costs as well as potentially ameliorating consumer lifestyle regarding dietary-related disease.

3.
J Appl Microbiol ; 111(2): 474-83, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21645181

ABSTRACT

AIM: The aims of this study were to identify antifungal lactic acid bacteria (LAB) and characterize their activity against the dermatophyte Trichophyton tonsurans. METHODS AND RESULTS: A total of 165 different LAB were isolated and initially screened for anti-Penicillium expansum activity. Five strains, which exhibited strong inhibitory activity, were then tested against the dermatophyte T. tonsurans DSM12285, where they also caused inhibition as observed by large fungal clearing on agar surface. The strongest inhibition was seen with Lactobacillus reuteri R2. When freeze-dried cell-free supernatant powder from this strain was incorporated in culture medium at concentrations >1%, growth of fungal colony was inhibited. Conidia germination was also inhibited under these conditions as determined by microscopy. The anti-T. tonsurans activity of Lact. reuteri R2 was not affected neither by heat treatment nor by proteolytic treatment using pronase E and proteinase K, indicating that the responsible agent(s) were nonproteinaceous in nature. CONCLUSIONS: Lactobacillus reuteri R2 was identified as having strong inhibitory activity against the dermatophyte T. tonsurans DSMZ12285. SIGNIFICANCE AND IMPACT OF THE STUDY: LAB are naturally associated with many foods and are well recognized for their biopreservative properties. The use of these and/or their products may well provide alternative safe approaches for the inhibition of dermatophytic fungi.


Subject(s)
Antibiosis , Limosilactobacillus reuteri/physiology , Trichophyton/growth & development , Animals , Bread/microbiology , Cattle , Cheese/microbiology , Culture Media , DNA, Bacterial/genetics , Edible Grain/microbiology , Food Microbiology , Freeze Drying , Hot Temperature , Humans , Hydrogen-Ion Concentration , Limosilactobacillus reuteri/drug effects , Limosilactobacillus reuteri/genetics , Mice , Peptide Hydrolases/pharmacology , RNA, Ribosomal, 16S/genetics , Spores, Fungal/growth & development , Swine
4.
J Prev Alzheimers Dis ; 7(4): 265-273, 2020.
Article in English | MEDLINE | ID: mdl-32920629

ABSTRACT

Aging is associated with a decrease in body and brain function and with a decline in insulin-like growth factor 1 levels. The observed associations between alterations in insulin-like growth factor 1 levels and cognitive functioning and Mild Cognitive Impairment suggest that altered insulin-like growth factor 1 signaling may accompany Alzheimer's disease or is involved in the pathogenesis of the disease. Recent animal research has suggested a possible association between insulin-like growth factor 1 levels and the Apolipoprotein E ε4 allele, a genetic predisposition to Alzheimer's disease. It is therefore hypothesized that a reduction in insulin-like growth factor 1 signaling may moderate the vulnerability to Alzheimer's disease of human Apolipoprotein E ε4 carriers. We address the impact of age-related decline of insulin-like growth factor 1 levels on physical and brain function in healthy aging and Alzheimer's disease and discuss the links between insulin-like growth factor 1 and the Apolipoprotein E ε4 polymorphism. Furthermore, we discuss lifestyle interventions that may increase insulin-like growth factor 1 serum levels, including physical activity and adherence to a protein rich diet and the possible benefits to the physical fitness and cognitive functioning of the aging population.


Subject(s)
Aging/metabolism , Alzheimer Disease/metabolism , Apolipoprotein E4/blood , Exercise , Insulin-Like Growth Factor I/metabolism , Alleles , Alzheimer Disease/prevention & control , Cognitive Dysfunction/metabolism , Humans , Risk Factors
5.
Gait Posture ; 52: 183-188, 2017 02.
Article in English | MEDLINE | ID: mdl-27915222

ABSTRACT

Elderly are confronted with reduced physical capabilities and increased metabolic energy cost of walking. Exoskeletons that assist walking have the potential to restore walking capacity by reducing the metabolic cost of walking. However, it is unclear if current exoskeletons can reduce energy cost in elderly. Our goal was to study the effect of an exoskeleton that assists plantarflexion during push-off on the metabolic energy cost of walking in physically active and healthy elderly. Seven elderly (age 69.3±3.5y) walked on treadmill (1.11ms2) with normal shoes and with the exoskeleton both powered (with assistance) and powered-off (without assistance). After 20min of habituation on a prior day and 5min on the test day, subjects were able to walk with the exoskeleton and assistance of the exoskeleton resulted in a reduction in metabolic cost of 12% versus walking with the exoskeleton powered-off. Walking with the exoskeleton was perceived less fatiguing for the muscles compared to normal walking. Assistance resulted in a statistically nonsignificant reduction in metabolic cost of 4% versus walking with normal shoes, likely due to the penalty of wearing the exoskeleton powered-off. Also, exoskeleton mechanical power was relatively low compared to previously identified optimal assistance magnitude in young adults. Future exoskeleton research should focus on further optimizing exoskeleton assistance for specific populations and on considerate integration of exoskeletons in rehabilitation or in daily life. As such, exoskeletons should allow people to walk longer or faster than without assistance and could result in an increase in physical activity and resulting health benefits.


Subject(s)
Aging , Ankle Joint/physiology , Exoskeleton Device , Foot/physiology , Mobility Limitation , Robotics/instrumentation , Aged , Biomechanical Phenomena , Electromyography , Exercise Test , Female , Humans , Male , Range of Motion, Articular , Reference Values , Shoes
6.
J Anim Sci ; 94(11): 4677-4687, 2016 11.
Article in English | MEDLINE | ID: mdl-27898943

ABSTRACT

Feeding fermented feed to weaned pigs may improve nutrient digestibility and gut health and thereby reduce diarrhea incidence. Effects of feeding wheat grain fermented for 24 h with were evaluated with 36 weaned pigs (7.3 kg BW). Fermented wheat grain contained (DM basis) 14.2% CP, 0.45% chemically available Lys, and 7.8% NDF, whereas unfermented wheat grain contained 16.4% CP, 0.45% chemically available Lys, and 9.9% NDF. Pigs were fed 6 mash wheat-based diets balanced for water content during 2 phases: Phase 1 diets for 1 wk (d 0-7) with 20% unfermented or fermented wheat and, subsequently, Phase 2 diets for 2 wk (d 8-21) with 50% unfermented or fermented wheat. The 6 diets were unfermented wheat (CTRL), unfermented and chemically acidified wheat (ACD), fermented wheat with TMW1.656 and 10% sucrose, fermented wheat with TMW1.656 and 5% glucose + 5% fructose, fermented wheat with LTH5794 and 10% sucrose, and fermented wheat with LTH5794 and 5% glucose + 5% fructose. Diets were formulated to provide 2.5 and 2.4 Mcal NE/kg and 5.3 and 5.0 g standardized ileal digestible Lys/Mcal NE for Phase 1 and 2 diets, respectively. Feeding fermented wheat reduced ( < 0.05) apparent total tract digestibility (ATTD) of diet DM (84.7 vs. 85.4%), GE (84.4 vs. 85.3%), and CP (81.8 vs. 83.6%) for d 15 through 21 compared with the CTRL and ACD diets. Weaned pigs fed fermented wheat diets had lower ( < 0.05) ADFI than pigs fed the CTRL and ACD diets for d 0 through 7. The ADFI, ADG, and G:F did not differ between pigs fed fermented and unfermented diets. Concentrations of acetic, propionic, and branched-chain fatty acids and total VFA in feces increased ( < 0.05) for pigs fed fermented wheat diets containing exopolysaccharides (EPS). However, VFA did not differ in ileal digesta. Villus height in the duodenum and jejunum increased in pigs fed fermented wheat without EPS ( < 0.05) compared with pigs fed fermented wheat with EPS. However, pigs fed the CTRL and ACD diets had longer ( < 0.05) villi and deeper crypts in the ileum than pigs fed fermented wheat. The ratio of villus height to crypt depth did not differ in the 3 segments of small intestine of weaned pigs. In conclusion, feeding fermented wheat grain diets to weaned pigs did not affect gut morphology, intestinal fermentation, growth performance, and ATTD of nutrients; however, EPS stimulated hindgut fermentation and may promote health benefits.


Subject(s)
Animal Feed/analysis , Diet/veterinary , Gastrointestinal Tract/anatomy & histology , Limosilactobacillus reuteri/physiology , Swine/physiology , Triticum/chemistry , Animal Nutritional Physiological Phenomena , Animals , Bioreactors , Digestion/drug effects , Feces/chemistry , Fermentation , Gastrointestinal Tract/drug effects , Probiotics , Swine/growth & development
7.
Gait Posture ; 41(1): 246-51, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25455436

ABSTRACT

While level walking with a pneumatic ankle-foot exoskeleton is studied extensively, less is known on uphill walking. The goals of this study were to get a better understanding of the biomechanical adaptations and the influence of actuation timing on metabolic cost during uphill walking with a plantarflexion assisting exoskeleton. Seven female subjects walked on a treadmill with 15% inclination at 1.36 ms(-1) in five conditions (4 min): one condition with an unpowered exoskeleton and four with a powered exoskeleton with onset of pneumatic muscle actuation at 19, 26, 34 and 41% of stride. During uphill walking the metabolic cost was more than 10% lower for all powered conditions compared to the unpowered condition. When actuation onset was in between 26 and 34% of the stride, metabolic cost was suggested to be minimal. While it was expected that exoskeleton assistance would reduce muscular activity of the plantarflexors during push-off, subjects used the additional power to raise the body centre of mass in the beginning of each step to a higher point compared to unpowered walking. This reduced the muscular activity in the m. vastus lateralis and the m. biceps femoris as less effort was necessary to reach the highest body centre of mass position in the single support phase. In conclusion, subjects can use plantarflexion assistance during the push-off to reduce muscular activity in more proximal joints in order to minimize energy cost during uphill locomotion. Kinetic data seem necessary to fully understand this mechanism, which highlights the complexity of human-exoskeleton interaction.


Subject(s)
Adaptation, Physiological/physiology , Gait/physiology , Muscle, Skeletal/physiology , Orthotic Devices , Robotics/methods , Walking/physiology , Adult , Biomechanical Phenomena , Electromyography , Exercise Test , Female , Humans
8.
J Am Dent Assoc ; 106(6): 836-7, 1983 Jun.
Article in English | MEDLINE | ID: mdl-6576019

ABSTRACT

Inappropriate use of dental equipment that is powered by highly compressed air may directly lead to the formation of subcutaneous emphysema that involves the fascial planes of the head and neck. The high-speed dental handpiece and the air and water dental syringe are the instruments that are most commonly implicated in the reported cases. The treatment of such cases requires a reassured patient, prophylactic antibiotic coverage, and close postoperative follow-up care. Patients should avoid maneuvers that could increase intraoral pressure. Complete resolution should be expected within one week.


Subject(s)
Dental Instruments/adverse effects , Emphysema/etiology , Subcutaneous Emphysema/etiology , Tooth Extraction/instrumentation , Female , Humans , Tooth Extraction/adverse effects
9.
Gait Posture ; 38(3): 495-9, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23465319

ABSTRACT

The goal of this study was to investigate adaptation to walking with bilateral ankle-foot exoskeletons with kinematic control that assisted ankle extension during push-off. We hypothesized that subjects would show a neuromotor and metabolic adaptation during a 24min walking trial with a powered exoskeleton. Nine female subjects walked on a treadmill at 1.36±0.04ms(-1) during 24min with a powered exoskeleton and 4min with an unpowered exoskeleton. Subjects showed a metabolic adaptation after 18.5±5.0min, followed by an adapted period. Metabolic cost, electromyography and kinematics were compared between the unpowered condition, the beginning of the adaptation and the adapted period. In the beginning of the adaptation (4min), a reduction in metabolic cost of 9% was found compared to the unpowered condition. This reduction was accompanied by reduced muscular activity in the plantarflexor muscles, as the powered exoskeleton delivered part of the necessary ankle extension moment. During the adaptation this metabolic reduction further increased to 16%, notwithstanding a constant exoskeleton assistance. This increased reduction is the result of a neuromotor adaptation in which subjects adapt to walking with the exoskeleton, thereby reducing muscular activity in all leg muscles. Because of the fast adaptation and the significant reductions in metabolic cost we want to highlight the potential of an ankle-foot exoskeleton with kinematic control that assists ankle extension during push-off.


Subject(s)
Adaptation, Physiological/physiology , Ankle Joint/physiology , Gait/physiology , Orthotic Devices , Oxygen Consumption/physiology , Quadriceps Muscle/physiology , Walking/physiology , Biomechanical Phenomena , Electromyography , Exercise Test , Female , Humans , Lower Extremity , Muscle, Skeletal/physiology , Robotics/instrumentation , Young Adult
10.
Biol Cell ; 51(1): 43-51, 1984.
Article in English | MEDLINE | ID: mdl-6237699

ABSTRACT

Two microanalytical methods, electron probe X ray analysis (E P M A) and ion mass analysis (I A M) were used to study gallium incorporation in normal tissues (kidney, liver, mammary gland, bone marrow, bone tissue) and in experimental tumors. The very high sensitivity of I M A makes possible the detection of very low concentration of gallium (1 ppm) with a spatial resolution of 0.5 micron, on the other hand, E P M A of lower sensitivity (100 ppm) makes possible the relation between the gallium concentration and the ultrastructure of the cell. It was shown that gallium is concentrated in the lysosomes of both types of tissues, where it is precipitated in an insoluble form. In addition, gallium is systematically combined with phosphorus in these precipitates. These observations suggest an active intralysosomal concentrating mechanism related to the presence of local phosphatase activity.


Subject(s)
Gallium/metabolism , Lysosomes/metabolism , Animals , Antineoplastic Agents/metabolism , Biological Transport, Active , Cells, Cultured , Electron Probe Microanalysis , Rats , Rats, Inbred Strains , Rhabdomyosarcoma/metabolism , Rhabdomyosarcoma/ultrastructure , Tissue Distribution
11.
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