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1.
J Environ Manage ; 223: 358-370, 2018 Oct 01.
Article in English | MEDLINE | ID: mdl-29936349

ABSTRACT

Characterisation of 27 types of biomass was performed together with an assessment of regional resource availability. Charcoal was produced under two conditions from all samples and their yields were compared. Sugarcane bagasse, sal and pine produced the best charcoal with a low volatile matter and high calorific value. The amount of high-quality charcoal which can be made within Nepal from the biomass types tested is equivalent to 8,073,000 tonnes of firewood a year or 51% of the yearly demand. The areas which would benefit the most from charcoal making facilities are the Mid-hills of the Western, Central and Eastern Development Regions, as well as the Terai in the Central and Eastern Development Regions. The main potential benefit is to convert agricultural residues which are underutilised because, in their original form, produce large quantities of smoke, to cleaner burning charcoal. The conversion of agricultural residues to charcoal is also a viable alternative to anaerobic digestion in the Mid-hills.


Subject(s)
Agriculture , Charcoal , Saccharum , Biomass , Cellulose , Nepal
2.
Nutr Metab Cardiovasc Dis ; 28(4): 402-410, 2018 04.
Article in English | MEDLINE | ID: mdl-29499850

ABSTRACT

BACKGROUND AND AIMS: Alterations to one-carbon metabolism, especially elevated plasma homocysteine (Hcy), have been suggested to be both a cause and a consequence of the metabolic syndrome (MS). A deeper understanding of the role of other one-carbon metabolites in MS, including s-adenosylmethionine (SAM), s-adenosylhomocysteine (SAH), and the methylation capacity index (SAM:SAH ratio) is required. METHODS AND RESULTS: 118 men and women with MS-risk factors were included in this cross-sectional study and cardiometabolic outcomes along with markers of one-carbon metabolism, including fasting plasma SAM, SAH, Hcy and vitamin B12 concentrations, were analysed. Multiple linear regression models were also used to examine the association between plasma one-carbon metabolites and cardiometabolic health features. We found that fasting plasma concentrations of Hcy, SAM and SAH were all positively correlated with markers of adiposity, including BMI (increase in BMI per 1-SD increase in one-carbon metabolite: 0.92 kg/m2 95% CI (0.28; 1.56), p = 0.005; 0.81 (0.15; 1.47), p = 0.02; 0.67 (-0.01; 1.36), p = 0.05, respectively). Hcy, but not SAM, SAH or SAM:SAH ratio was associated with BMI and body fat percentage after mutual adjustments. SAM concentrations were associated with higher fasting insulin (9.5% 95% CI (0.3; 19.5) per SD increase in SAM, p = 0.04), HOMA-IR (10.8% (0.8; 21.9), p = 0.03) and TNF-α (11.8% (5.0; 19.0), p < 0.001). CONCLUSION: We found little evidence for associations between SAM:SAH ratio and cardiometabolic variables, but higher plasma concentrations of SAM, SAH and Hcy are related to an overall higher risk of metabolic dysfunctions. The studies were registered at www.clinicaltrials.gov (NCT01719913 &NCT01731366).


Subject(s)
Metabolic Syndrome/blood , S-Adenosylhomocysteine/blood , S-Adenosylmethionine/blood , Adiposity , Adult , Aged , Biomarkers/blood , Blood Glucose/metabolism , Blood Pressure , Body Mass Index , Cross-Sectional Studies , Fasting/blood , Female , Health Status , Humans , Inflammation Mediators/blood , Insulin/blood , Insulin Resistance , Male , Metabolic Syndrome/diagnosis , Metabolic Syndrome/physiopathology , Middle Aged , Vitamin B 12/blood , Young Adult
3.
Aliment Pharmacol Ther ; 45(5): 643-652, 2017 03.
Article in English | MEDLINE | ID: mdl-28052442

ABSTRACT

BACKGROUND: Therapy for coeliac disease (CD) mainly relies on following a gluten-free diet (GFD); however, a serum marker for gluten intake has yet to be established. AIM: To evaluate the utility of alkylresorcinol concentrations for detecting gluten intake in studies of human and mouse. METHODS: Alkylresorcinol concentrations were compared among treated patients with coeliac disease (n = 34), untreated coeliac disease patients (n = 36) and controls (n = 33). Furthermore, seven additional coeliac disease patients whose serum samples were available at diagnosis and after GFD were evaluated. In mice studies, alkylresorcinol concentrations were compared in the serum of five mice fed a regular chow and 10 mice fed lifelong with a gluten-free chow. In addition, the effect of adding gluten on changes of alkylresorcinol concentrations was also evaluated. RESULTS: Total alkylresorcinol concentrations were significantly lower in treated with coeliac disease [median (IQR), 3 (2-8) nmol/L], compared to untreated patients [median (IQR), 32 (11-74) nmol/L; P < 0.0001] or healthy controls [median (IQR), 54 (23-112) nmol/L; P < 0.0001]. Moreover, alkylresorcinol concentrations in coeliac disease patients significantly decreased after introduction of a GFD (median, 34 nmol/L at diagnosis vs. 5 nmol/L after GFD, P = 0.02). In the mice, median (IQR) total alkylresorcinol concentrations in serum samples of mice fed lifelong with a gluten-free chow was 1.8 (1.6-2.3) nmol/L, which was further significantly increased to 16 (11-22) nmol/L after 8 days of feeding with the gluten-free chow that had gluten added to it. (P = 0.008). CONCLUSION: Serum alkylresorcinol concentrations could be a useful marker for dietary gluten in coeliac disease.


Subject(s)
Celiac Disease/diet therapy , Diet, Gluten-Free , Glutens/administration & dosage , Resorcinols/blood , Adult , Animals , Biomarkers/metabolism , Case-Control Studies , Female , Humans , Male , Mice , Mice, Transgenic , Middle Aged
4.
Bioresour Technol ; 214: 637-644, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27187568

ABSTRACT

This study investigates the influence of pH on extraction of nitrogen and phosphorus from swine manure following hydrothermal treatment. Conditions include thermal hydrolysis (TH) at 120°C and 170°C, and hydrothermal carbonisation (HTC) at 200°C and 250°C in either water alone or in the presence of 0.1M NaOH, H2SO4, CH3COOH or HCOOH. Phosphorus extraction is pH and temperature dependent and is enhanced under acidic conditions. The highest level of phosphorus is extracted using H2SO4 reaching 94% at 170°C. The phosphorus is largely retained in the residue for all other conditions. The extraction of nitrogen is not as significantly influenced by pH, although the maximum N extraction is achieved using H2SO4. A significant level of organic-N is extracted into the process waters following hydrothermal treatment. The results indicate that operating hydrothermal treatment in the presence of acidic additives has benefits in terms of improving the extraction of phosphorus and nitrogen.


Subject(s)
Manure , Nitrogen/isolation & purification , Phosphorus/isolation & purification , Waste Disposal, Fluid/methods , Animals , Carbon/chemistry , Chemical Fractionation , Hydrogen-Ion Concentration , Hydrolysis , Nitrogen/chemistry , Phosphorus/chemistry , Sulfuric Acids/chemistry , Swine , Temperature , Water
5.
Bioresour Technol ; 200: 951-60, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26615335

ABSTRACT

Thermal hydrolysis and hydrothermal processing show promise for converting biomass into higher energy density fuels. Both approaches facilitate the extraction of inorganics into the aqueous product. This study compares the behaviour of microalgae, digestate, swine and chicken manure by thermal hydrolysis and hydrothermal processing at increasing process severity. Thermal hydrolysis was performed at 170°C, hydrothermal carbonisation (HTC) was performed at 250°C, hydrothermal liquefaction (HTL) was performed at 350°C and supercritical water gasification (SCWG) was performed at 500°C. The level of nitrogen, phosphorus and potassium in the product streams was measured for each feedstock. Nitrogen is present in the aqueous phase as organic-N and NH3-N. The proportion of organic-N is higher at lower temperatures. Extraction of phosphorus is linked to the presence of inorganics such as Ca, Mg and Fe in the feedstock. Microalgae and chicken manure release phosphorus more easily than other feedstocks.


Subject(s)
Biomass , Inorganic Chemicals/analysis , Manure/analysis , Microalgae/metabolism , Temperature , Waste Products , Water/chemistry , Animals , Carbon/analysis , Chickens , Chlorella/metabolism , Hydrogen-Ion Concentration , Hydrolysis , Nitrogen/analysis , Phosphorus/analysis , Potassium/analysis , Swine
6.
Chemosphere ; 145: 518-27, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26702555

ABSTRACT

The potential for biochar and hydrochar to adsorb phosphate and ammonium is important for understanding the influence of these materials when added to soils, compost or other high nutrient containing environments. The influence of physicochemical properties such as mineral content, surface functionality, pH and cation exchange capacity has been investigated for a range of biochars and hydrochars produced from waste-derived biomass feedstocks. Hydrochars produced from hydrothermal carbonisation at 250 °C have been compared to low and high temperature pyrolysis chars produced at 400-450 °C and 600-650 °C respectively for oak wood, presscake from anaerobic digestate (AD), treated municipal waste and greenhouse waste. In spite of differences in char physicochemical properties and processing conditions, PO4-P and NH4-N sorption capacities ranged from about 0 to 30 mg g(-1) and 105.8-146.4 mg g(-1) respectively. Chars with high surface areas did not possess better ammonium adsorption capacities than low surface area chars, which suggests that surface area is not the most important factor influencing char ammonium adsorption capacity, while char calcium and magnesium contents may influence phosphate adsorption. Desorption experiments only released a small fraction of adsorbed ammonium or phosphate (<5 mg g(-1) and a maximum of 8.5 mg g(-1) respectively).


Subject(s)
Ammonium Compounds/analysis , Charcoal/chemistry , Phosphates/analysis , Soil/chemistry , Waste Management/methods , Adsorption , Biomass , Hot Temperature , Wood/chemistry
7.
Bioresour Technol ; 176: 257-66, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25461011

ABSTRACT

Reforming ethanol ('EtOH') into hydrogen rich syngas using the aqueous fraction from pine bio-oil ('AQ') as a combined source of steam and supplementary organic feed was tested in packed bed with Ni-catalysts 'A' (18wt%/α-Al2O3) and 'B' (25wt%/γ-Al2O3). The catalysts were initially pre-reduced by H2, but this was followed by a few cycles of chemical looping steam reforming, where the catalysts were in turn oxidised in air and auto-reduced by the EtOH/AQ mixture. At 600°C, EtOH/AQ reformed similarly to ethanol for molar steam to carbon ratios (S/C) between 2 and 5 on the H2-reduced catalysts. At S/C of 3.3, 90% of the carbon feed converted on catalyst A to CO2 (58%), CO (30%) and CH4 (2.7%), with 17wt% H2 yield based on dry organic feedstock, equivalent to 78% of the equilibrium value. Catalyst A maintained these outputs for four cycles while B underperformed due to partial reduction.


Subject(s)
Biofuels , Ethanol/chemistry , Hydrogen/chemistry , Pinus/chemistry , Catalysis , Nickel/chemistry , Nitrogen/chemistry , Water/chemistry
8.
Bioresour Technol ; 102(7): 4841-8, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21295976

ABSTRACT

Hydrothermal processing of high lipid feedstock such as microalgae is an alternative method of oil extraction which has obvious benefits for high moisture containing biomass. A range of microalgae and lipids extracted from terrestrial oil seed have been processed at 350 °C, at pressures of 150-200 bar in water. Hydrothermal liquefaction is shown to convert the triglycerides to fatty acids and alkanes in the presence of certain heterogeneous catalysts. This investigation has compared the composition of lipids and free fatty acids from solvent extraction to those from hydrothermal processing. The initial decomposition products include free fatty acids and glycerol, and the potential for de-oxygenation using heterogeneous catalysts has been investigated. The results indicate that the bio-crude yields from the liquefaction of microalgae were increased slightly with the use of heterogeneous catalysts but the higher heating value (HHV) and the level of de-oxygenation increased, by up to 10%.


Subject(s)
Biofuels , Biotechnology/methods , Hot Temperature , Lipids/isolation & purification , Microalgae/chemistry , Catalysis , Chromatography, High Pressure Liquid , Water/chemistry
9.
Bioresour Technol ; 102(7): 4876-83, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21316946

ABSTRACT

The brown macro-alga Laminaria saccharina was converted into bio-crude by hydrothermal liquefaction in a batch reactor. The influence of reactor loading, residence time, temperature and catalyst (KOH) loading was assessed. A maximum bio-crude yield of 19.3 wt% was obtained with a 1:10 biomass:water ratio at 350 °C and a residence time of 15 min without the presence of the catalyst. The bio-crude had an HHV of 36.5 MJ/kg and is similar in nature to a heavy crude oil or bitumen. The solid residue has high ash content and contains a large proportion of calcium and magnesium. The aqueous phase is rich in sugars and ammonium and contains a large proportion of potassium and sodium.


Subject(s)
Biofuels , Biotechnology/methods , Hot Temperature , Laminaria/chemistry , Calcium/analysis , Magnesium/analysis , Potassium/analysis , Quaternary Ammonium Compounds/analysis , Sodium/analysis , Water/chemistry
10.
Bioresour Technol ; 102(1): 215-25, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20599375

ABSTRACT

A range of model biochemical components, microalgae and cyanobacteria with different biochemical contents have been liquefied under hydrothermal conditions at 350 °C, ∼200 bar in water, 1M Na(2)CO(3) and 1M formic acid. The model compounds include albumin and a soya protein, starch and glucose, the triglyceride from sunflower oil and two amino acids. Microalgae include Chlorella vulgaris,Nannochloropsis occulata and Porphyridium cruentum and the cyanobacteria Spirulina. The yields and product distribution obtained for each model compound have been used to predict the behaviour of microalgae with different biochemical composition and have been validated using microalgae and cyanobacteria. Broad agreement is reached between predictive yields and actual yields for the microalgae based on their biochemical composition. The yields of bio-crude are 5-25 wt.% higher than the lipid content of the algae depending upon biochemical composition. The yields of bio-crude follow the trend lipids>proteins>carbohydrates.


Subject(s)
Biotechnology/methods , Eukaryota/metabolism , Oils/metabolism , Carbohydrates/pharmacology , Chlorella vulgaris/metabolism , Cyanobacteria/metabolism , Hot Temperature , Lipids/chemistry , Porphyridium/metabolism , Predictive Value of Tests , Pressure , Reproducibility of Results
11.
Bioresour Technol ; 102(1): 226-34, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20685112

ABSTRACT

To avoid negative impacts on food production, novel non-food biofuel feedstocks need to be identified and utilised. One option is to utilise marine biomass, notably fast-growing, large marine 'plants' such as the macroalgal kelps. This paper reports on the changing composition of Laminaria digitata throughout it growth cycle as determined by new technologies. The potential of Laminaria sp. as a feedstock for biofuel production and future biorefining possibilities was assessed through proximate and ultimate analysis, initial pyrolysis rates using thermo-gravimetric analysis (TGA), metals content and pyrolysis gas chromatography-mass spectrometry. Samples harvested in March contained the lowest proportion of carbohydrate and the highest ash and alkali metal content, whereas samples harvested in July contained the highest proportions of carbohydrate, lowest alkali metals and ash content. July was therefore considered the most suitable month for harvesting kelp biomass for thermochemical conversion to biofuels.


Subject(s)
Animal Feed/analysis , Biotechnology/methods , Laminaria/growth & development , Seasons , Bioelectric Energy Sources , Biofuels , Biomass , Gas Chromatography-Mass Spectrometry , Kelp/growth & development , Metals/analysis , Seawater/analysis , Thermogravimetry , Time Factors
12.
Bioresour Technol ; 99(14): 6494-504, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18194859

ABSTRACT

A preliminary classification of five macroalgae from the British Isles; Fucus vesiculosus, Chorda filum, Laminaria digitata, Fucus serratus, Laminaria hyperborea, and Macrocystis pyrifera from South America, has been presented in terms of a Van Krevelen diagram. The macroalgae have been characterised for proximate and ultimate analysis, inorganic content, and calorific value. The different options for thermal conversion and behaviour under combustion and pyrolysis have been evaluated and compared to several types of terrestrial biomass including Miscanthus, short rotation Willow coppice and Oat straw. Thermal treatment of the macroalgae has been investigated using thermogravimetry (TGA) and pyrolysis-gc-ms. Combustion behaviour is investigated using TGA in an oxidising atmosphere. The suitability of macroalgae for the different thermal processing routes is discussed. Ash chemistry restricts the use of macroalgae for direct combustion and gasification. Pyrolysis produces a range of pentosans and a significant proportion of nitrogen containing compounds. High char yields are produced.


Subject(s)
Bioelectric Energy Sources , Eukaryota/classification , Eukaryota/physiology , Species Specificity
13.
Conf Proc IEEE Eng Med Biol Soc ; 2004: 2492-5, 2004.
Article in English | MEDLINE | ID: mdl-17270778

ABSTRACT

High-temperature thermal therapy for the treatment of prostate cancer is currently being applied as a minimally-invasive alternative over traditional forms of treatment. Catheter-based interstitial and transurethral ultrasound applicators are being developed for controlled and selective thermal ablation of prostaric tissues with concurrent MR thermal imaging. As part of this treatment strategy we have devised a transurethral cooling catheter and a cooling jacket to be placed over the endorectal MR imaging coil to protect the urethral mucosa and rectal wall from thermal damage during treatment. The cooling efficiencies and protective abilities of these devices were evaluated in vivo within three canine prostate glands. Invasive and MR derived temperature measurements within the prostate and rectal wall indicate that the protective influence of the endorectal cooling extends 5-10 mm from the rectal wall into the dorsal prostate. The urethral cooling extends approximately 5 mm from the cooling balloon. The protective capabilities were further verified with subsequent histological analysis with TTC stained tissue sections and contrast enhanced T1-weighted MR images post treatment. Both of these cooling devices are compatible with the MR thermometry and can be used to protect the urethral mucosa and rectal wall during prostate thermal ablation with interstitial and transurethral ultrasound devices.

14.
Int J Hyperthermia ; 20(7): 739-56, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15675669

ABSTRACT

High-temperature thermal therapy is emerging as a feasible treatment option for prostate cancer and benign prostatic hyperplasia. Previous investigations have demonstrated distinct advantages of catheter-based ultrasound technology over other heating modalities for thermal ablation therapies, with significant potential for better spatial control and faster heating times. The purpose of this study was to develop ultrasound devices and techniques specifically for treating prostate cancer in conjunction with magnetic resonance thermal imaging (MRTI) to monitor and control treatment progression. Directional transurethral applicators have been designed with arrays of sectored tubular (90 degrees active acoustic sector) or with narrow planar transducer segments and integrated with a flexible delivery catheter with a cooling balloon. This applicator can be rotated within the prostatic urethra to target specific regions during treatment. MRI compatible catheter-cooled interstitial ultrasound applicators with 180 degrees active acoustic sectors were developed specifically to treat the prostate. These applicators may be implanted through the perineum into the posterior portion of the prostate, with their heating energy directed away from the rectum. Both heating strategies were evaluated via biothermal simulations and in vivo experiments within canine prostate (n = 3). During the in vivo studies, MRTI was used to monitor treatment temperatures, cytotoxic thermal doses (t43 > 240 min) and corresponding maximum temperature thresholds (Tmax > 52 degrees C) within three imaging planes simultaneously. Urethral and endorectal cooling was employed with both treatment strategies to provide further protection of the urethral mucosa and rectum from thermal damage. Results using the transurethral applicators demonstrated that narrow zones of coagulation (approximately 30 degrees sector for planar, approximately 90 degrees for tubular), extending up to 20 mm from the urethra to the periphery of the prostate gland, could be produced within 10-15 min. Further, rotation of the applicator during treatment could be used to destroy larger regions in the prostate. Experiments using multiple interstitial directional applicators (approximately 180 degrees active sectors), implanted within the posterior margin of the prostate with the energy directed away from the rectum, produced contiguous zones of thermal coagulation which extended from the posterior prostate toward the anterior-lateral periphery of the gland. Both transurethral and interstitial treatment strategies demonstrated significant potential for thermal ablation of localized prostate cancer, particularly when MRTI is used to guide and assess treatment.


Subject(s)
Catheter Ablation/instrumentation , Hyperthermia, Induced/instrumentation , Magnetic Resonance Imaging , Prostatic Hyperplasia/therapy , Prostatic Neoplasms/therapy , Ultrasonic Therapy/instrumentation , Animals , Equipment Design , Humans , Hyperthermia, Induced/methods , Male , Prostatic Hyperplasia/surgery , Prostatic Neoplasms/surgery
15.
J Dairy Sci ; 86(5): 1789-96, 2003 May.
Article in English | MEDLINE | ID: mdl-12778589

ABSTRACT

The preservation of crimped wheat grains by three bacterial inoculants or a chemical additive was compared. Crimped wheat grain [56.8 g dry matter (DM)/kg] was conserved in 1.75-kg plastic bag, mini-silos without treatment, with 4L/tonne of Crimpstore (CS; an additive containing a mixture of ammonium formate, propionate, ethyl benzoate, and benzoate, SAS Kelvin Cave, Ltd., UK) or 1 x 10(5) cfu/g of each of three inoculant additives containing Lactobacillus fermentum (A), Leuconostoc mesenteroides (B), and Lactobacillus buchneri (C). Six replicates were conserved per treatment. Ensiling DM losses, chemical composition, fermentation characteristics, and aerobic stability were measured in the silages after 68 d of ensiling. All the silages were well fermented and remained stable for 84 h after aeration. Subsequently, the rate of deterioration was slowest in crimped grains treated with CS treatment, followed by those treated with inoculant C, while those treated with inoculant A deteriorated most rapidly. Residual water-soluble carbohydrate concentration was higher in crimped grains treated with CS than those treated with the inoculants. Ammonia nitrogen concentrations were lowest in CS-treated crimped grains, followed by inoculants C and A. DM losses were greater in CS-treated crimped grains than in crimped grains treated with inoculants A and C. In vivo digestibility was also measured in Texel-cross lambs fed a grass silage basal diet supplemented with the additive-treated crimped grains or a conventional, lamb finisher concentrate. Dry matter intake and digestibility were unaffected by treatment. In conclusion, bacterial inoculants containing L. buchneri are promising preservatives for crimped wheat grains.


Subject(s)
Food Additives/administration & dosage , Food Preservation/methods , Lactobacillus/physiology , Leuconostoc/physiology , Nutritive Value , Triticum , Animals , Digestion , Eating , Edible Grain , Fatty Acids, Volatile/metabolism , Fermentation , Oxygen , Sheep/physiology , Silage , Triticum/microbiology
16.
J Mater Sci Mater Med ; 12(7): 583-8, 2001 Jul.
Article in English | MEDLINE | ID: mdl-15348250

ABSTRACT

Osteoprotegerin (OPG) is a naturally secreted protein that decreases bone resorption by inhibiting osteoclast differentiation and activation while promoting osteoclast apoptosis [8]. In this study, the effects of osteoprotegerin injections on long bone mechanical and material properties were investigated in young male Sprague-Dawley rats. OPG increased fracture strength at the femur mid-diaphysis in three-point bending by 30%, without affecting the elastic or maximum strength. At the femoral neck, OPG significantly increased the elastic (45%), maximum (15%), and fracture (35%) strengths. There was not a difference in microhardness at the femur mid-diaphysis in comparing the placebo and OPG groups. There were, however, significant increases in whole bone dry mass (25%), mineral mass (30%), organic mass (17%), and percent mineralization (4%); percent mineralization at the mid-diaphysis (3%); and percent mineralization at the distal epiphysis (6%) due to the OPG treatment. While OPG decreased endocortical bone formation (52%), total bone area, endocortical bone area, and periosteal bone formation were maintained with OPG treatment. A 30% increase in the X-ray opacity of the bone at the proximal metaphysis of the right tibiae was observed. Overall, OPG increased mineralization and strength indices in the rat femur. Its effects on strength were more pronounced in the femoral neck than at the mid-diaphysis.

17.
J Agric Food Chem ; 47(12): 5019-22, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10606566

ABSTRACT

Oca (Oxalis tuberosa Mol.) or New Zealand yam, in common with other members of this genus, contains oxalate, an antinutritive factor. Twelve South American and two New Zealand cultivars of oca were analyzed for total and soluble oxalate contents of the tubers. The range of total oxalate levels was 92-221 mg/100 g of fresh weight. Levels of soluble and total oxalate extracted from the tubers were not significantly different, suggesting that no calcium oxalate is formed in the tubers. The oxalate concentrations obtained in this study for oca suggest that previously reported values are too low and that oca is a moderately high oxalate-containing food. This is the first report of a tuber crop containing moderate to high levels of soluble oxalates in the tubers and no insoluble oxalates.


Subject(s)
Oxalates/analysis , Plant Roots/chemistry , Plants, Edible/chemistry , Chromatography, High Pressure Liquid , Humans , New Zealand , Solubility , South America
18.
Dig Dis Sci ; 42(8): 1580-6, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9286220

ABSTRACT

The 1993 Milwaukee Cryptosporidium outbreak posed several questions regarding appropriate management and prognosis of inflammatory bowel disease patients acutely infected with this organism. We prospectively identified and monitored 12 patients with stable ulcerative colitis or Crohn's disease who suffered abrupt clinical decompensation during the outbreak. All recovered to baseline at < or = 60 days. In patients receiving immunosuppressive therapy, mean duration of symptoms was no longer than in patients without it. Antibiotics did not clearly reduce duration of illness. Two additional patients without a history of intestinal disease presented with ileitis and colitis, respectively, initially suggesting Crohn's disease. Both recovered completely without specific therapy. We conclude that cryptosporidiosis may present as an acute relapse of inflammatory bowel disease and responds to standard therapy; antibiotics confer no obvious benefit. Immunosuppressive therapy does not predispose to chronic or severe illness in these patients. Cryptosporidiosis may present with acute findings initially mimicking Crohn's disease.


Subject(s)
Cryptosporidiosis/complications , Inflammatory Bowel Diseases/complications , Adult , Aged , Cryptosporidiosis/diagnosis , Cryptosporidiosis/epidemiology , Cryptosporidiosis/therapy , Disease Outbreaks , Female , Humans , Inflammatory Bowel Diseases/diagnosis , Inflammatory Bowel Diseases/therapy , Male , Middle Aged , Wisconsin/epidemiology
19.
Free Radic Biol Med ; 10(3-4): 243-7, 1991.
Article in English | MEDLINE | ID: mdl-1650739

ABSTRACT

The data obtained from radiation chemistry experiments, and, particularly, pulse radiolysis studies that allow absolute rate constants to be obtained, can be of considerable value to investigations in free radical biology. In this article, we review leading sources of rate, spectral, and thermodynamic data (including critical review articles) where readers can obtain this information.


Subject(s)
Chemistry , Free Radicals , Radiation , Chemical Phenomena , Computer Communication Networks , Databases, Bibliographic , Hydroxides , Hydroxyl Radical , Thermodynamics
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