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Trichothecenes are the most prevalent mycotoxins contaminating cereal grains. Some of them are also considered as the virulence factors of Fusarium head blight disease. However, the mechanism behind the structure-activity relationship for trichothecenes remains unexplained. Filling this information gap is a crucial step for developing strategies to manage this large family of mycotoxins in food and feed. Here, we perform an in-depth re-examination of the existing structures of Saccharomyces cerevisiae ribosome complexed with three different trichothecenes. Multiple binding interactions between trichothecenes and 25S rRNA, including hydrogen bonds, nonpolar pi stacking interactions and metal ion coordination interactions, are identified as important binding determinants. These interactions are mainly contributed by the key structural elements to the toxicity of trichothecenes, including the oxygen in the 12,13-epoxide ring and a double bond between C 9 and C 10 . In addition, the C 3 -OH group also participates in binding. The comparison of three trichothecenes binding to the ribosome, along with their binding pocket architecture, suggests that the substitutions at different positions impact trichothecenes binding in two different patterns. Moreover, the binding of trichothecenes induced conformation changes of several nucleotide bases in 25S rRNA. This then provides a structural framework for understanding the structure-activity relationships apparent in trichothecenes. This study will facilitate the development of strategies aimed at detoxifying mycotoxins in food and feed and at improving the resistance of cereal crops to Fusarium fungal diseases.

Mycotoxins are secondary metabolites produced by several species of fungi, including the Fusarium , Aspergillus , and Penicillium species. Currently, more than 300 structurally diverse mycotoxins are known, including a group called minor mycotoxins, namely enniatins, beauvericin, and fusaproliferin. Beauvericin and enniatins possess a variety of biological activities. Their antimicrobial, antibiotic, or ionoforic activities have been proven and according to various bioassays, they are believed to be toxic. They are mainly found in cereal grains and their products, but they have also been detected in forage feedstuff. Mycotoxins in feedstuffs of livestock animals are of dual concern. First one relates to the safety of animal-derived food. Based on the available data, the carry-over of minor mycotoxins from feed to edible animal tissues is possible. The second concern relates to detrimental effects of mycotoxins on animal health and performance. This review aims to summarize current knowledge on the relation of minor mycotoxins to livestock animals.

In this study, 15 different mycotoxins were estimated in three staple cereals from selected agro-ecological regions in Nigeria using a 'novel' green extraction method, pressurized hot water extraction (PHWE) in comparison to a conventional solvent extraction method. Discrimination of the results of PHWE and solvent extraction using principal component analysis (PCA) and orthogonal projection to latent structures discriminate analysis (OPLS-DA) did not yield any differential clustering patterns. All maize samples (n = 16), 32% (n = 38) of sorghum and 35% (n = 37) of millet samples were positive for at least one of the 15 tested mycotoxins. Contamination levels for the cereals were higher in the warm humid rain forest region and gradually decreased towards the hot and arid region in the north of the country. The results demonstrate the applicability of PHWE as a possible alternative extraction method to conventional methods of extraction, which are solvent based.

Gramine is a natural indole alkaloid that has been isolated from different raw plants occurring mainly in Avena sativa, etc. The study was aimed to investigate the possible in vitro antioxidant, in vitro mutagenic, in vitro antimutagenic, and in vivo genotoxic activity of gramine using ferric reducing ability of plasma (FRAP) assay, Metal chelating, Ames bacterial reverse mutation test, and the mouse bone marrow micronucleus assay as well as chromosomal aberration. Four concentrations of gramine viz. 250, 500, 1000, and 2000 μg/mL were evaluated for its antioxidant activity in FRAP Assay and Metal Chelating Test. Four concentrations of gramine (1250 μg/plate, 2500 μg/plate, 5000 μg/plate, and 10 000 μg/plate) were employed in Salmonella typhimurium strains to study the mutagenicity in the presence and absence of standard mutagens, 2-aminofluorene (2-AF), sodium azide (SA), and 2-nitrofluorene (2-NF). Three doses, i.e. 0.1, 0.2, and 0.3 × the LD 50 of gramine (i.e. 50 mg/kg, 100 mg/kg, and 150 mg/kg) were administered orally to either sex of Swiss albino mice for 48 h to study the genotoxic activity in micronucleus assay as well as chromosomal aberration. Gramine showed potent antioxidant activity in both the assay. Gramine at the given dose lacks mutagenicity as well as found to possess antimutagenic efficacy. Interestingly, S9 enzymes increase the antimutagenic activity in a dose-dependent manner. There was no significant increase in the frequency of micronucleated polychromatic erythrocytes (MNPCEs), as well as no significant difference in the percentage of chromosomal aberrations was observed between the gramine groups and the negative groups but percentage of polychromatic erythrocytes (PCEs) is found to be higher in all the gramine groups. These results indicate significant antioxidant, non-mutagenic as well as non-genotoxic activity of gramine in vitro and in vivo in the given doses.

The contamination of cereals with arsenic (As) is a global health and agronomic concern. This study compared the physiological response, As uptake and As speciation in the grains and above ground tissues of 20 wheat cultivars exposed to 5 mg As kg -1 soil as either arsenate (As V ) or dimethylarsenate (DMA) under glasshouse conditions. Germination rates for the majority of cultivars exceeded 80% for the majority of cultivars when exposed to As V , but fell significantly to 20-40% when exposed to DMA. For a number of cultivars, grain yields were 20-50% lower when plants were exposed to DMA compared to As V . Grain As concentrations were between 0.6 and 1.6 μg As g -1 grain across the twenty cultivars when exposed to As V , whereas grain As concentrations were much higher (2.2-4.6 μg As g -1 grain) when exposed to DMA. When plants were exposed to As V , 100% of the As present in the grain was found as inorganic As while in plants exposed to DMA, 70-90% of As was present as DMA with the remainder found as inorganic As. DMA is believed to be incorporated by plants via silica (Si) acid channels and assessment of grain Si concentrations demonstrated that up to 40% less Si was accumulated in grains when plants were exposed to DMA. The decreased germination rates and grain yields in the presence of DMA is similar to the symptoms described for straight head disease in rice, which has been linked to DMA exposure. The results presented here indicate some analogous processes occur in wheat to those described in rice. We hypothesise that exposure to DMA may have inhibited Si-metabolism and translocation which resulted in both developmental impairment and possibly an increased susceptibility to soil pathogens., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background: An outbreak of a chronic liver disease of unidentified cause, known as "Unidentified Liver Disease (ULD)" by local communities was first observed in a rural village in Tigray, northern-Ethiopia in 2001. Little was known about the geographical extent, trend, and epidemiology of the disease., Methods: The Ethiopian Public Health Institute (EPHI) by then Ethiopian Health and Nutrition Research Institute (EHNRI), Centers for Disease Control and Prevention, World Health Organization, and Tigray Regional Health Bureaue established the ULD surveillance system in 2009 to characterize and monitor trends for this emerging disease and to identify cases for treatment and follow up. A large-scale official training was provided to the surveillance staff on case identification, management and reporting. In absence of a confirmatory test, the system used simple case definitions that could be applied by frontline staff with varying clinical training. To maximize resources, health extension workers already conducting household visits in affected communities identified cases and increased community awareness about the disease. A team was placed in Shire, in close proximity to the outbreak region, to provide support and collect reports from health facilities and district health offices., Results: As of September 2011, a total of 1,033 cases, including 314 deaths were identified. Contamination of locally produced grains with several pyrrolizidine alkaloid producing plants was identified cause of the disease. Staff interviews identified that shortage and turnover of trained staff were major challenges., Lessons Learned: Long term dedication by frontline staff, using simple case definitions to identify cases, and active collection of missing reports were critical for surveillance of this chronic non-infectious disease of unknown cause in a rural, resource-limited setting.

Evidence indicates that the densely cultivated region of northeastern China acts as a source for the wind-borne agent of Kawasaki disease (KD). KD is an acute, coronary artery vasculitis of young children, and still a medical mystery after more than 40 y. We used residence times from simulations with the flexible particle dispersion model to pinpoint the source region for KD. Simulations were generated from locations spanning Japan from days with either high or low KD incidence. The postepidemic interval (1987-2010) and the extreme epidemics (1979, 1982, and 1986) pointed to the same source region. Results suggest a very short incubation period (<24 h) from exposure, thus making an infectious agent unlikely. Sampling campaigns over Japan during the KD season detected major differences in the microbiota of the tropospheric aerosols compared with ground aerosols, with the unexpected finding of the Candida species as the dominant fungus from aloft samples (54% of all fungal strains). These results, consistent with the Candida animal model for KD, provide support for the concept and feasibility of a windborne pathogen. A fungal toxin could be pursued as a possible etiologic agent of KD, consistent with an agricultural source, a short incubation time and synchronized outbreaks. Our study suggests that the causative agent of KD is a preformed toxin or environmental agent rather than an organism requiring replication. We propose a new paradigm whereby an idiosyncratic immune response, influenced by host genetics triggered by an environmental exposure carried on winds, results in the clinical syndrome known as acute KD.

Cereals are among the most vulnerable substrates to mycotoxin contamination. One of the major fungal species colonising the ecosystem of stored grain is Penicillium verrucosum because of its ability to produce ochratoxin A (OTA). Knowledge of favourable environmental conditions promoting fungal growth and mycotoxin biosynthesis seems to be a crucial step towards preventing mycotoxin formation in stored grain. The aim of the study was to examine the effect of temperature and different cereal substrates (wheat, triticale, rye, barley, maize, rice) on fungal growth and OTA and citrinin (CIT) production by a mycotoxin-producing P. verrucosum strain at one moisture content. The correlation between fungal growth and mycotoxin biosynthesis was also investigated. For this purpose, cereal substrates moistened, autoclaved and inoculated with P. verrucosum spores were stored at 10°C, 20°C and 30°C for 40 days. After the storage period, the ergosterol (ERG) content as a fungal growth biomarker and OTA and CIT levels were determined using HPLC. Fungal growth was observed on all cereals at each temperature. Maximum ERG levels were found at 30°C and the values ranged from 401 to 3280 mg kg(-1) of grain. Among tested cereals, the highest ergosterol content was found on rice at all applied temperatures. Accumulation of OTA and CIT was detected in samples stored at 20°C and 30°C, while optimal conditions for the production of both mycotoxins were observed at 20°C. The maximum concentration of OTA (31.9 ± 4.3 (SD) μg kg(-1)) and CIT (74.8 ± 5.7 μg kg(-1)) were found on rice. The ability to biosynthesise OTA and CIT at 10°C was not detected. Analysis of variance showed that single factors, temperature and cereal matrices and their interactions had significant effects on ERG, OTA and CIT levels. Optimal conditions for fungus growth did not coincide with the ones for mycotoxin formation.

Deoxynivalenol (DON) is a prevalent and resistant mycotoxin found in cereals and related products. Adsorbents appear to provide an opportunity to decrease DON absorption in animals but, due to their specificity, it is very difficult to evaluate their actual efficacy. It is pointless to extrapolate results obtained with one mycotoxin to another and even to extrapolate results obtained in vitro in buffer to an in vivo situation. We carried out experiments to characterize the properties of potential DON adsorbents. Initial tests in buffer pH 7 allowed us to focus on six adsorbents: activated charcoal, cholestyramin, Saccharomyces cerevisiae mannans, algal beta-glycan, fungal beta-glycan and leguminous plant. The use of equilibrium sorption models suggested a non-saturated phenomenon and involved variable mechanisms according to the specific material. Subsequent tests with a Caco-2 cell model showed a high reduction in DON cytotoxicity on proliferative intestinal cells and DON absorption by differentiated intestinal cells when adsorbent was added (except for cholestyramin). Otherwise, values were not always in accordance with those obtained in buffer. Our work allowed us to identify five potential DON adsorbents and to propose a complementary in vitro test allowing improved determination of adsorbent properties.

UK rye-based cereal products were analysed for six major ergot alkaloids using an in-house-validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method that distinguished -ine and -inine epimers (isomers). Ergot alkaloids were detected in 25 of 28 samples subject to quantification limits of 1-3 µg kg(-1), including all of eleven rye crispbreads that had up to 340 µg kg(-1). Continental-style rye breads contained up to 121 µg kg(-1). Loaf breads, bread-mix flours, and crackers contained only low levels of alkaloids. Ergotamine, ergocristine, and ergosine were the predominant ergot alkaloids in terms of level and frequency of occurrence. There were no apparent differences in the ergot levels between the organic and non-organic products, although the numbers tested were low. Most rye breads had a ratio of -ines to -inines of about 1.5, and rye crispbreads had lower and more variable -ine to -inine ratios.

Ochratoxin A (OA) is a naturally occurring mycotoxin with nephrotoxic properties that can contaminate plant food products. OA concentrations were assessed in commonly consumed food items in the North Central Province of Sri Lanka, where chronic kidney disease is diagnosed at epidemic proportions. Ninety-eight randomly selected food samples were analysed. Mycotoxin was detected in the extract by using a MycoMonitor Ochratoxin A ELISA assay kit (Helica Biosystems Inc., USA). The levels of OA found in these food commodities were below the recommended statutory maximum limit and are unlikely to be a potential risk factor for nephropathy in the North Central Province of Sri Lanka.

Simple extraction of prolamins from cereal flour using 70% aqueous ethanol leads to co-extraction of lipids and other secondary products. Treatment of the crude extract with an excess of pure ethanol resulted in the removal of the majority of these compounds. Prolamin extracts obtained following ethanol precipitation showed little difference to products of more complex, multi stage, selective extractions, when compared using MALDI-TOF mass spectrometry. Toxicity tests on enzymic digests of ethanol-precipitated prolamins from coeliac-toxic cereals, coeliac-non-toxic cereals and oats were carried out using a rat liver lysosome assay. The prolamins from the ethanol-precipitated extracts showed greater activity than those extracted using only 70% ethanol for extraction. As the ethanol precipitation method is simple and provides a prolamin extract of sufficient purity for further evaluation, this procedure has been adopted as an alternative to more tedious procedures for preparation of cereal prolamins.

Turkey produces about 80% of the total hazelnut crop of the world. About 75% of the production are exported. In Turkey hazelnuts are traditionally sun dried, and may be subject to mold growth and subsequent mycotoxin formation due to prolonged drying time under humid and rainy weather conditions. Drying hazelnuts in a reasonable time after harvest is necessary for mycotoxin-free, high-quality products. In general, nuts and cereals contaminated by the toxins pose a potential hazard not only to the people of the producer countries, but also to people of the importing countries, if they should be regarded as safe by inefficient sampling plans, therefore preventing toxin formation actually benefits very large populations. Deterioration and health hazards associated with toxin contaminated hazelnuts and other nuts and cereals have similar causes and consequences; therefore, deterioration of the nuts and cereals in storage has been reviewed by considering as many grains and nuts as possible, then special reference was made to hazelnuts. Proper preharvest practices followed by proper drying and safe storage reduces the hazards associated with contamination by the toxins. This article reviews the pre- and post-harvest practices, and the grain- and nut-drying systems required for toxin-free products. Because drying is the major unit operation involving this process, the drying systems and the mathematical models required for their design is also discussed.

The effects of Pearl millet, fermented millet, or processed fermented millet were investigated in 15 goats assigned as untreated controls, Pearl millet-fed (166.6g/animal/d), fermented millet-fed (166.6 g/animal/d or 83.3g/animal/d), and processed fermented millet-fed (166.6g/ animal/d). Pearl millet caused goiter within 72-108 d, and changes in thyroid follicles were correlated with clinical manifestations and alterations in serum and tissue iodine and selenium concentrations. Neither fermented nor processed fermented millet produced goiter, but their toxicity was characterized by ruminal bloat, dyspnea, diarrhea, ataxia, and enterohepatonephrotoxicity with death within 5-15 d. Organ lesions correlated with changes in serum enzymes and other serum constituents, hematology, and tissue and serum iodine and selenium concentrations.

Hepatic changes induced by phenethyl isothiocyanate (PEITC) in the liver of rats were determined by quantitative microscopy. Groups of male Fischer-344 rats were fed either a standard, cereal-based diet (Wayne rodent meal) or a purified diet (AIN-76A) containing PEITC at concentrations of 0.75 and 6.0 mmol/kg for 13 wk. Severe hepatic lipidosis was observed in control rats fed the purified diet. Addition of PEITC to the purified diet significantly reduced lipid content in hepatocytes. In contrast, lipid content in the liver of the rats fed the cereal-based diet containing PEITC was greater than in control rats maintained on the same diet. In addition, dose-related reductions in hepatocyte, lipid droplet, peroxisome, and mitochondrial volumes were observed in PEITC-treated rats fed the cereal-based diet. These results indicate that PEITC exerts differential effects on the liver of rats fed either the cereal-based or purified diet.

Animal diets used in toxicity studies are prepared either from natural ingredients (cereal-based diet) or from more refined products (purified diet). The type of diet may influence both the outcome of the study and the values obtained with the various parameters in test and control animals. To detect the parameters sensitive to changes in diet composition, short-term (4-wk) studies were conducted in rats, mice and hamsters fed either a cereal-based diet or the AIN-76A purified diet supplemented with vitamins and minerals at the highest recommended levels for each of the species used. Although the purified diet was more palatable to rats and showed a higher protein quality, growth rate and food intake were generally slightly higher with the cereal-based diet in each of the species examined. The haematological values of the two diet groups were generally comparable. On the cereal-based diet the production of faeces was considerably higher than on the purified diet and was accompanied by a higher weight of the caecum. These findings were attributed to the relatively high level and mixed composition of the fibre fraction in the cereal-based diet. Blood levels of cholesterol and phospholipids were clearly lower on the cereal-based diet than on the purified diet. Because the differences were probably due to the level and composition of the fibre fraction, they support the suggestion to replace the 5% cellulose of the AIN-76A diet by a higher level of a more composite but well defined source of dietary fibre.

The study was aimed at evaluation of the effect of dust, produced at crushing the serpentine, on the soil and crops in Nasławice. The serpentine dust, apart from asbestos, contains also magnesium, calcium, chromium and nickel. These elements have been determined in the soil and plants by means of the standard methods generally used in agricultural chemistry, whereas asbestos content was determined by means of X-ray diffractometry and polarization microscopy. The dust of the crops harvested contained asbestos fibres and, in the plants, the increased content of nickel an chromium was found. The highest amount of asbestos was found in soil in the area at a distance of up to 50 km from the emission source. The soil contains also the increased amounts of chromium and sporadically cadmium.

The aim of the present study was to investigate the levels of trichothecenes in representative samples of Finnish and imported cereals and feeds from the 1987 and 1988 crops. Trichothecene concentrations were determined in samples as trimethylsilylether derivatives by a gas chromatograph equipped with a mass selective detector (GC-MSD) using selected ion monitoring (SIM) which proved to be a reliable and sufficiently sensitive technique. Representative samples of Finnish and imported oats, wheat, barley, rye, maize gluten, soy granules, rapeseed, turnip rapeseed, fish meal, poultry feed and pig feed were analysed employing 19-nortestosterone as an internal standard. Almost all grain and feed samples contained deoxynivalenol (DON) from 7 to 300 micrograms/kg and smaller amounts (13-120 micrograms/kg) of 3-acetyldeoxynivalenol (3-AcDON). The most toxic trichothecenes, T-2, HT-2 toxins and nivalenol (NIV) and also zeralenone (ZEN) were found at low concentrations in some samples. Six lots of oats containing 1.3-2.6 mg/kg of DON and 0.2-0.6 mg/kg of 3-AcDON were found in the Finnish grain samples. Silo samples of almost all imported grains contained DON but at levels below 50 micrograms/kg. Imported grains contained no other trichothecenes. DON, 3-AcDON and ZEN were found in imported feedstuffs at low concentrations.

Cd and Pb contents were determined in milk formulae, milk-cereal formulae and cereal formulae produced by Okregowe Zakłady Koncentratów Spozywczych (OZKS) (Regional Food Concentrates Processing Plants) for infants and children up to 3 years of age. The major parts of the assortments were found to contain products whose cadmium and/or lead contents exceeded the admissible norms. These contents were as follows: in milk formulae: from less than 2 to 8 micrograms Cd/kg and from less than 20 to 180 micrograms Pb/kg; in milk-cereal formulae: from less than 2 to 20 micrograms Cd/kg and from less than 20 to 180 micrograms Pb/kg; in cereal formulae from less than 2 to 70 micrograms Cd/kg and from less than 20 to 400 micrograms Pb/kg. Contents of Cd and Pb were the highest in cereal formulae mainly in those produced of wheat flour and buckwheat-rice flour. Determinations of Cd and Pb contents in raw materials and in some cereal intermediate products revealed that the occurrence of excessively high Cd and Pb contents in the cereal-containing formulae was due to contamination of the cereal raw materials with these metals.

Wheat flour and other cereals toxic for celiac patients contain an alcohol-soluble protein fraction that, under experimental conditions simulating in vivo protein digestion, yields peptides that agglutinate undifferentiated K 562(S) cells. In contrast, cereals well tolerated in celiac disease (i.e., rice and maize) do not. Furthermore, purified A-gliadin peptides that damage in vitro-cultured flat celiac mucosa are powerful agglutinins for K 562(S) cells, whereas A-gliadin peptides that do not show any adverse in vitro effect on celiac intestine lack agglutinating activity. Mannan, acetylglucosamine, and its oligomers (N,N'-diacetylchitobiose and N,N',N"-triacetylchitotriose) were able to prevent and reverse cell agglutination induced by peptides from all the toxic cereals. Moreover, mannan and N,N',N"-triacetylchitotriose exhibited a protective effect on intestinal mucosa specimens of patients with active celiac disease cultured with wheat protein-derived peptides. These data are consistent with the hypothesis that the agglutinating and toxic peptides are bound by carbohydrates.

The experiments on mice were used to study the mutagenic effect of green oat, with the lead content 24 times higher than its permissible level in vegetable products. The animals were fed with the oat for a long time (during 1/3 and 1/2 of their life), then the cytogenetic analysis of the bone marrow was made, and the dominant lethal mutations were studied in the sex cells. The results of the study showed no manifest chromosomal aberrations in the somatic cells, and no dominant lethal mutations in the sex cells of the mice, thus evidencing that under conditions of the experiments conducted, the green plant with a high lead content did not produce mutagenic effect.

The chromatographic method for determining the toxicity of the cereal crop grain affected by micromycates F. sporotrichiella is proposed. The method is based on the separation of the lipids extracted from the grain under examination in a thin layer of the silica gel and detection on the chromatogram of two toxic fractions with Rf-0.06 and 1.22 fluorecent in the UV-light by emitting greyish-green and emerald-green coloured light. The chromatographic method is more sensitive, visually obvious and quicker by comparison with the biological ones.

We measured nonspecific bronchial reactivity to inhaled histamine in 26 lifetime nonsmoking grain handlers and 29 lifetime nonsmoking unexposed control subjects matched for age, sex and specific conductance. Routine lung function tests revealed a total lung capacity that was higher in control subjects than in workers (P less than 0.05) with no difference in other subdivisions of lung volume, or expiratory flow rates between the two groups. An index of allergy was significantly greater in the control subjects than in the grain workers (P less than 0.01). None of the grain handlers was sensitive to grain dust by history or by skin tests. Respiratory symptoms (cough, sputum, dyspnea, or wheezing) were more prevalent in the grain workers than in controls (P less than 0.05). The mean concentration of histamine required to reduce the specific conductance by 35 percent was 4.5 +/- 2.0 mg/ml in grain workers and 5.9 +/- 3.0 mg/ml in controls (P less than 0.05). Chronic exposure to grain dust in nonallergic individuals appears to be associated with both increased prevalence of respiratory symptoms and increased nonspecific bronchial reactivity when compared to nonexposed control subjects.

The field studies leading to possible intervention procedures are reviewed. Currently the most promising form of intervention is the prevention of aflatoxin contamination of foodstuffs. It is essential that these are monitored and their efficacy in lowering the incidence of liver cancer measured. The association of liver cancer with hepatitis B infection may be a confounding factor and the impact of this on the study population must also be considered. The imminent production of vaccines for hepatitis B infection may provide an alternative or additional mode of intervention. The possibilities for intervention in liver cell cancer appear one of the brighter prospects for primary prevention of a cancer.

Male weanling rats fed diets containing fermented and unfermented tannin-free sorghum meals naturally contaminated with traces of ochratoxin A, zearalenone, and an unidentified toxic substance developed anorexia. Mean changes in body weight over a 28-day feeding period for rats fed fermented and unfermented sorghum meal and ANCR casein diets of 8% protein were -2.8, +13.8, and +100.5 g, respectively. Rats fed fermented sorghum meal developed alopecia; hematological findings showed a decreased mean corpuscular volume, hypochromic microcytosis, balanced leukopenia, and hypoproteinuria . Histological findings showed testicular hypoplasia of the germinal epithelium and no mature spermatozoa. Necrosis and mineralization in Henle's loop were also observed. No damage was apparent to the liver, cerebellum, cerebrum, spleen, or adrenal glands.

Growth and heavy-metal uptake of various food crops and grass cultivated on harbour dredge spoils were studied, and health aspects in consuming the marketable products were discussed. Vegetables (potato, carrot, radish, endive, lettuce) and grass (English ryegrass) performed well on dredge spoils, but small grains (wheat, barley) were affected by manganese deficiency. As compared with crops grown on uncontaminated reference soils, there was a net accumulation of As and heavy metals, especially so Cd, Zn and Cu, and a reduced uptake of Mn. Mainly because of the elevated Cd concentrations of the edible parts, exceeding the guideline of 0.1 mg/kg in fresh matter, the harbour dredge spoils investigated are considered unfit for the production of food crops, but may be used as grassland for dairy cattle. Highest Cd concentrations were attained in leafy vegetables and wheat (grain) and lowest in potato (tuber).

Distiller's grains with solubles (DGS) was obtained from a commercial fermentation of 90% corn and 10% wheat for ethanol production. The DGS was freeze-dried and proximate analysis resulted in 17.6% protein, 5.5% fat, 3.0% ash, 17.3% moisture, 21.6% neutral detergent fiber, and 35% carbohydrate by difference. Fatty acid analysis and amino acid analysis were similar to those of corn. Tryptophan was the limiting amino acid with a chemical score of 47. Protein Efficiency Ratio (PER) was 1.49. Mutagenicity testing of lipid and aqueous extracts of DGS in the Ames Salmonella mammalian microsome assay were negative.

Exposure of mice to grain dust in a dusting chamber for 2-80 days led to a pulmonary macrophage response but no interstitial pulmonary damage. The macrophages contained prominent paracrystalline cytoplasmic inclusions.

Gliadins from wheat, rye, and oats, and from wheat glutenin were digested with pepsin, trypsin, and pancreatin and the products (PTC digests) chromatographed on sulphopropyl (SP) Sephadex. Fractions eluted near neutral pH from wheat, rye, and oats gliadin digests all had very similar amino acid composition, although the oats fraction was higher in sulphur-containing amino acids. The major amino acids present in all were glutamine/glutamic acid and proline. The amount of fraction eluted near neutral pH from oats gliadin digest was about 13% of that eluted from digests of wheat and rye gliadins. Moreover, the yield of gliadin from oatmeal was only 0.5% compared with 2.4% and 2.8% from rye and wheat flours respectively. The amount of fraction eluted from wheat glutenin digest was about 70% of that obtained from wheat and rye gliadin digests. The fractions eluted near neutral pH from all protein digests were defectively digested by remission coeliac mucosa, and D-xylose excretion tests with the fraction from the wheat gliadin digest (fraction 9) indicated that it is harmful to subjects with coeliac disease, whereas the other fractions of this digest gave no such evidence. The results of the present work indicate that counterpart fractions to fraction 9 obtained from wheat glutenin and rye and oats gliadins may also be important in the aetiology of coeliac disease.

Twelve young macaque monkeys were fed with grain and water from areas actively endemic or non-endemic for Kashin-Beck disease. Both dietary grain and water from geographical areas endemic for Kashin-Beck disease induced a sequence of pathological changes in the growth plates and articular cartilage and biochemical changes in the serum and urine of monkeys. These changes are similar to those in human Kashin-Beck disease. It is considered that this may be a simple and valuable model for the further study of this disease and its management and control. The results suggest that the pathogenetic factors of Kashin-Beck disease relate both to grain and to water in the diet in endemic areas. The experiment also shows that certain serum enzyme concentrations correlate with chondronecrosis.

Peptic-tryptic-cotazym and peptic-tryptic digests were obtained, simulating in vivo protein digestion, from pure "bread" wheat gliadins and from rye, barley, and oats prolamine and tested on small intestine cultures from fetal rats. When tested at a concentration of 0.1 mg of peptides/ml of culture medium the peptic-tryptic-cotazym and peptic-tryptic digests of gliadin and prolamines were very active in slowing in vitro development of fetal rat intestine and in increasing the occurrence and severity of degenerative changes. The ability of some sugars to interfere with inhibition of fetal intestinal morphogenesis induced by these peptides was also tested. Mannan at a concentration of 0.1 mM was effective in allowing intestinal morphogenesis to take place in the presence of prolamine peptic-tryptic-cotazym and prolamine peptic-tryptic digests of the four toxic cereals. Some oligomers of N-acetyl-glucosamine were also effective in blocking the inhibitory effect of "bread" wheat gliadin peptides. These data are compatible with the hypothesis that some sugars may exert a protective effect on the toxic activity of cereal prolamin peptides on the human celiac intestine.

Crude metabolites of 21 of 60 fungal cultures isolated from some of the common cereals collected from different parts of India were found to be toxic. Of these toxin-producing fungi, 79% caused hepatic pathology of varying severity in mice. Serum glutamate pyruvate transaminase values and blood urea nitrogen were found to be high in such experimental animals.

Coeliac disease is caused by prolamines, the storage proteins of some cereals, located in the endosperm. Cereals do not all have the same toxicity. The four wheat prolamine groups (alpha, beta, gamma and omega gliadins), visible in electrophoresis at acid pH, have been isolated and their toxicities compared by observing the morphological changes in intestinal biopsies cultured in vitro when peptic-tryptic digests of the studied proteins were added to the culture medium. The toxicity was found to be mainly located in the alpha and beta-gliadins and in peptides of 5 to 10 000 molecular weight. Peptides, resulting from peptic-tryptic hydrolysis, varied in length as a direct function of their proline content. In fact, peptide bond splitting by pepsin and trypsin is known to be blocked by proline. Thus, proline content determines peptide length and toxicity. Wheat, rye and barley toxicities were compared on the basis of a correlation between toxicity and the alpha- and beta-gliadin-like prolamine contents of these cereals. Electrophoretic estimation of alpha- and beta-gliadin-like prolamine content gave the following prediction of relative toxicity (in decreasing order): wheat, triticale, rye, barley and oats.

The characteristics of the toxic effect of rose-stained grain of fusarial and non-fusarial nature, as well as the grain experimentally challenged with the toxic strain Fusarium sporotrichiella 53315, were studied basing on the analysis of morphological changes in the internal organs of young rat given orally extracts from the samples studied. The tissue aging processes under the effect of the extract doses producing no irreversible pathologic changes were investigated. It was shown that the extracts of rose-stained natural grain, fusarial and without signs of fusaridiosis, produced similar pathological changes in the morphological structures of the organs in the young rats, the toxicity grew with the increase of the per cent of rose-stained grain. Dystrophic changes in the parenchymatous organs and impairment of the structure of the immunogenesis organs were recorded with a low content of rose-stained grain (3-3.5%), the changes in some organs at the structural and cellular level were also revealed, however, they were less manifest and evidenced a regional antigenic stimulation.

Blood clearance rates of volatile fatty acids, lactate and succinate were estimated in cattle following a single rapid intravenous injection of a Na-anion solution. Bromosulfophthalein was administered immediately before the anion to monitor the effects upon liver function, blood circulation, and dose equilibrium. Acetate, propionate, and valerate at doses up to 5 mmole/kg were cleared quickly from the blood by a first-order process without effects either upon the animal or bromosulfophthalein clearance. Injection of acetic acid solutions produced no effects. Butyrate was toxic at doses above 1 mmole/kg and progressively affected both the rate and progress of bromosulfophthalein clearance as the dose increased. Lactate and succinate were toxic and lethal at doses around 0.25 mmole/kg, and caused both reduced rates and altered progress of bromosulfophthalein clearance. The toxic reactions resulted in total collapse from loss of muscle tone. The butyrate and lactate effects were accentuated when the anion solutions were injected at low pH where a large portion of the anion would be unionized. Levels of butyrate, lactate and succinate in the rumens of feedlot cattle were high enough to provide toxic doses of these anions. The results are discussed in terms of the effects of excess rumen production of these anions upon the liver function and health of feedlot cattle.

Peptic-tryptic-Cotazym (PTC) digests were obtained, simulating in vivo protein digestion, from rice, maize, rye, oats, barley, and sorghum prolamines and tested on small intestine cultures from rat fetus. The PTC digests of the prolamine fractions from rice and maize, even when tested at a concentration as high as 0.5 mg/ml, did not affect in vitro differentiation and maturation of fetal rat jejunum that took place in vitro in a way comparable to what happens in vivo. On the contrary, the PTC digests of prolamines from rye, oats, barley, and sorghum were very active in slowing down in vitro development of fetal rat intestine. These results further strengthen earlier findings and all together show that there is a strong correlation between toxicity results of cereal and/or cereal components assessed with clinical trials or in vitro systems based on bioptic specimens of intestinal mucosa from celiac patients and with the culture of rat fetal intestine. Therefore, the rat fetal intestine culture is considered to be an adequate model for screening and investigating cereal peptides which are toxic for the celiac small intestinal mucosa.

In our continued studies on hybrid proteins for use as cytotoxins and possible suicide transport agents, we have begun to investigate the use of ribosome-inactivating proteins (RIP) isolated from grain. The RIP from barley has been purified to homogeneity by modifications of the methods of Roberts and Selitrennikoff and crosslinked to the binding subunit B of the seed toxin ricin (RTB). The resulting hybrid was purified by a combination of gel filtration and affinity chromatography on acid-washed Sepharose 4B. This model suicide transport agent was assayed in vitro against K-562 cells and was found to be cytotoxic in a dose-dependent manner (ID50 = 0.15 micrograms/ml). Lactose inhibited the toxicity of the hybrid, indicating that cytotoxicity was dependent on the cell binding property of the ricin B moiety. In addition, free RIP and free ricin B, either alone or in combination, were nontoxic over this concentration range. The in vivo effects of the RTB-RIP hybrid were assessed by pressure microinjection into the vagus nerves of rats. Injection of 0.18 to 6.5 micrograms of conjugate resulted in death of vagal sensory but not motor neurons after 3-17 days. The cytotoxic changes in vagal sensory neurons were identical to those previously observed with a variety of RIP toxins such as ricin.