170 research outputs found

    In vitro production of trichothecenes and zearalenone by Fusarium isolates from equatorial barley (Hordeum vulgare l.) grown in Kenya

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    Fusarium head blight (scab) is a devastating disease of wheat and barley throughout the world. The disease has been reported worldwide wherever cereals are grown, cutting across diverse ecological and geographical distribution. In addition to being pathogenic to plants, which may cause severe crop yield reduction, many Fusarium species are also capable of producing mycotoxins deleterious to human health as secondary metabolites. Fusarium toxins are commonly detected in wheat, barley,maize, rice and beer. Traditionally malted barley (Hordeum vulgare L.) is the principal ingredient in clear beer and Fusarium toxins incidences are of major concern. Moreover, the spent grain from the brewing industry is used as feed and presence of mycotoxins can lead to harmful effects on domestic animals and also find a way into the human food chain. Studies carried out in Kenya have revealed presence of various Fusarium species with ability to produce mycotoxins and presence of Fusarium toxins in wheat and maize and beer. Based on the ubiquitous nature of Fusarium mold and the fact that barley production takes place in maize and wheatgrowing areas, this study set out to investigate the occurrence of Fusarium molds in Equatorial barley grown in Kenya and the ability of the isolates to produce selected mycotoxins. Grain samples were obtained from newly delivered barley lots originating from two regions and stored grain awaiting malting after break of dormancy from Kenya Maltings Ltd., Nairobi. The Fusarium isolates were identified to species level based on cultural and morphological characteristics. Additionally, they were screened in-vitro on rice cultures for their ability to produce Type A trichothecenes (T–2 toxin, HT–2 toxin, Diacetoxyscirpenol), Type B trichothecenes (deoxynivalenol and nivalenol) and Zearalenone. Samples from all sources were contaminated with Fusarium, but at varying magnitudes - 50%, 33.3% and 25% for barley kernels originating from Timau, Olchoro and in-storage grain with no common history of origin, respectively. The distribution of the species showed some regional specificity. F. graminearum and F. poae predominated in kernels sourced from Olchoro region. All strains of F. graminearum produced both deoxynivalenol and zearalenone. F. poae strains and F. chlamydosporum did not produce detectable amounts of the screened mycotoxins. However, two inconclusively identified isolatesof Fusarium spp. isolated from Timau samples produced deoxynivalenol only. The study revealed that a number of toxigenic Fusarium spp. do occur in Equatorial barley grown in Kenya

    Antioxidative and radical scavenging activities of propolis extracts in food models

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    Propolis samples collected from Mwingi, Malindi, Uasin-gishu and Meru south districts in Kenya were extracted using ethanol and methanol. The methanol extracts were further partitioned into ethyl acetate, hexane and aqueous fractions. The extracts were concentrated and dried in vacuum evaporator. Their antioxidative activities were tested in linoleic acid-â-carotene system and in soybean oil. The extracts’ radical scavenging activities against 2,2–diphenyl-1-picrylhydrazil (DPPH) were alsostudied. Significant differences were observed between the samples as well as within the samples’ various extracts. The ethanol extract of propolis (EEP) and the ethyl acetate fractions from all four samples had higher 2,2–diphenyl-1-picrylhydrazil (DPPH) radical scavenging activity compared to the aqueous and the hexane extracts at a concentration of 500 ìg/ml. Malindi EEP at a concentration of 500 ìg/ml had a significantly (p < 0.05) higher radical scavenging activity (87.7%) than all the other EEP’s. The least radical scavenging activity was observed in Uasin-gishu EEP with73.3%. The Mwingi ethyl acetate extract at a concentration of 500 ìg/ml had 79.2% radical scavenging activity which was the highest observed amongst the ethyl acetate fractions and the least was in Uasin-gishu sample having 66.1% activity. The highest activity among the aqueous extracts was 7.1% in Meru South sample at a concentration of 500 ìg/ml. Radical scavenging activity did not differ in all four aqueous fractions. There was no significant difference (p < 0.05) observed in the antioxidation activity of Mwingi, Meru south and Malindi EEPP’s, in the linoleic acid-â-carotene system at a concentration of 500 ìg/ml. The EEP’s were the most active against oxidation of the system with a range of 61.7% in Uasin-gishu sample to 71.8% in Malindi sample while the aqueous was the least active with a range of 5.8% to 11.7% in Uasin-gishu and Malindi samples respectively. The EEP’s at a concentration of 1mg/ml showed greater activity against antioxidation of soybean oil compared to butylated hydroxyltoluene (BHT) at a concentration of 0.2 ìg/ml for thefirst 25 days of the test. After the 25th day, there was sharp increase in peroxide values in all the EEPs showing loss of antioxidation strength.Key words: Propolis, Radical scavenging, antioxidation activit

    Nutritional and functional properties of a complementary food based on Kenyan amaranth grain (Amaranthus cruentus)

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    The objective of this study was to determine the nutritional and functional properties of Amaranthus cruentus grain grown in Kenya for preparation of a ready-to-eat product that can be recommended as infant complementary food. Amaranth grains were subjected to steeping and steam pre-gelatinization to produce a ready-to-eat nutritious product with improved solubility during reconstitution. The effect of processing on the functional and nutritional properties of amaranth grain was analyzed. Two blends were prepared from raw and processed amaranth grains. Standard procedures of Association of Official Analytical Chemists (AOAC) were used to determine the proximate chemical composition. High Performance Liquid Chromatography (HPLC) was used quantify amino acid, water soluble vitamins, α-tocopherols and phytates, while Atomic Absorption Flame Emission spectrophotometry was used to determine the mineral element composition. Fatty acid composition was determined using Gas Liquid Chromatography (GLC). Tannin composition was determined using vanillin hydrochloric acid method. The overall results indicated that processing amaranth grain did not significantly affect its nutritional and physicochemical properties. Amaranth grain product was rich in protein with 0.5 g/10g of lysine, a limiting amino acid in cereals, and methionine, a limiting amino acid in pulses. The product had good amount 44.4 mg/100g of α-tocopherols important for infant development. The product was also rich in oleic acid (36.3%) and linoleic acid (35.9%) with some amounts of linolenic acid (3.4%) that are important for infant growth. It also had good amounts of minerals of importance such as potassium (324.4 mg/100g), phosphorous (322.8 mg/100g), calcium 189.1 (mg/100g), magnesium (219.5 mg/100g), iron (13.0 mg/100g) and zinc (4.8 mg/100g). Considering amaranth grain product fed to infant three times a day, at a reconstitution of 15% product, the levels of magnesium, manganese and tocopherols were far above the recommended intakes, while protein, phosphorous, iron, zinc, riboflavin and niacin were above the average requirements. Therefore, reconstituting the product with milk would enrich the deficient nutrients, especially for iron and zinc which are crucial nutrients for infants. The processing method is a practical approach aimed at combating the problem of malnutrition among infants and young children in Kenya and other developing countries. The product developed in this study would also be appropriate for use in geriatrics care and also in immuno-compromised individuals. The technique in this study can be easily adopted at both household and village levels to produce high protein-energy weaning food to help enhance the nutritional status of Kenyans

    Mitochondrial and nuclear genes suggest that stony corals are monophyletic but most families of stony corals are not (Order Scleractinia, Class Anthozoa, Phylum Cnidaria)

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    Modern hard corals (Class Hexacorallia; Order Scleractinia) are widely studied because of their fundamental role in reef building and their superb fossil record extending back to the Triassic. Nevertheless, interpretations of their evolutionary relationships have been in flux for over a decade. Recent analyses undermine the legitimacy of traditional suborders, families and genera, and suggest that a non-skeletal sister clade (Order Corallimorpharia) might be imbedded within the stony corals. However, these studies either sampled a relatively limited array of taxa or assembled trees from heterogeneous data sets. Here we provide a more comprehensive analysis of Scleractinia (127 species, 75 genera, 17 families) and various outgroups, based on two mitochondrial genes (cytochrome oxidase I, cytochrome b), with analyses of nuclear genes (ßtubulin, ribosomal DNA) of a subset of taxa to test unexpected relationships. Eleven of 16 families were found to be polyphyletic. Strikingly, over one third of all families as conventionally defined contain representatives from the highly divergent "robust" and "complex" clades. However, the recent suggestion that corallimorpharians are true corals that have lost their skeletons was not upheld. Relationships were supported not only by mitochondrial and nuclear genes, but also often by morphological characters which had been ignored or never noted previously. The concordance of molecular characters and more carefully examined morphological characters suggests a future of greater taxonomic stability, as well as the potential to trace the evolutionary history of this ecologically important group using fossils

    The cometary composition of a protoplanetary disk as revealed by complex cyanides

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    Observations of comets and asteroids show that the Solar Nebula that spawned our planetary system was rich in water and organic molecules. Bombardment brought these organics to the young Earth's surface, seeding its early chemistry. Unlike asteroids, comets preserve a nearly pristine record of the Solar Nebula composition. The presence of cyanides in comets, including 0.01% of methyl cyanide (CH3CN) with respect to water, is of special interest because of the importance of C-N bonds for abiotic amino acid synthesis. Comet-like compositions of simple and complex volatiles are found in protostars, and can be readily explained by a combination of gas-phase chemistry to form e.g. HCN and an active ice-phase chemistry on grain surfaces that advances complexity[3]. Simple volatiles, including water and HCN, have been detected previously in Solar Nebula analogues - protoplanetary disks around young stars - indicating that they survive disk formation or are reformed in situ. It has been hitherto unclear whether the same holds for more complex organic molecules outside of the Solar Nebula, since recent observations show a dramatic change in the chemistry at the boundary between nascent envelopes and young disks due to accretion shocks[8]. Here we report the detection of CH3CN (and HCN and HC3N) in the protoplanetary disk around the young star MWC 480. We find abundance ratios of these N-bearing organics in the gas-phase similar to comets, which suggests an even higher relative abundance of complex cyanides in the disk ice. This implies that complex organics accompany simpler volatiles in protoplanetary disks, and that the rich organic chemistry of the Solar Nebula was not unique.Comment: Definitive version of the manuscript is published in Nature, 520, 7546, 198, 2015. This is the author's versio

    Clinical relevance of heparin-PF4 complex antibody in DVT after total joint replacement

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    <p>Abstract</p> <p>Background</p> <p>Antibodies to the heparin-platelet factor-4 (HPF-4) complex (HIT antibodies) have been observed in patients with heparin-induced thrombocytopenia (HIT). These antibodies are thought to be involved in thrombosis through activation of platelet/endothelial cells. This prospective study was conducted to determine the incidence of post-operative HIT antibodies to assess the associated risk of deep vein thrombosis (DVT) in patients undergoing total knee arthroplasty (TKA) or total hip arthroplasty (THA).</p> <p>Methods</p> <p>We studied 104 patients who underwent unilateral primary TKA (n = 44) and primary THA (n = 60) with short-duration prophylaxis (1–2 days of a fixed dose of unfractionated heparin). HIT antibodies were assayed using a sandwich-type ELISA before the operation and after heparin treatment (post-operative day 7).</p> <p>Results</p> <p>In the clinical outcome, the incidence of symptomatic DVT was 15.4% (16/104, TKA; 10, THA 6) and pulmonary embolism (PE) was not observed. The total seroconversion rate of HIT antibodies at post-operative day 7 was 34.6% (36/104). Among 36 seroconverted patients, 11 (30.6%) developed symptomatic DVT and 5 out of 68 of the non-seroconverted patients (7.4%) developed symptomatic DVT. The incidence for DVT was significantly higher in the seroconverted patients compared with that of the non-seroconverted patients (odds ratio 5.5, 95%CI: 1.7–17.6 <it>p </it>= 0.0028). Furthermore, in the patients with symptomatic DVT, the titer of HIT antibodies at post-operative day 7 was significantly higher compared with those without symptomatic DVT.</p> <p>Conclusion</p> <p>Our data therefore suggest that seroconversion for HIT antibodies generated by heparin is associated with a risk of DVT in patients undergoing total joint replacement.</p

    The opposite effects of fluvoxamine and sertraline in the treatment of psychotic major depression: a case report

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    <p>Abstract</p> <p>Background</p> <p>Psychotic major depression is a clinical subtype of major depressive disorder. A number of clinical studies have demonstrated the efficacy of the combination of an antidepressant (for example, a tricyclic antidepressant or selective serotonin reuptake inhibitor (SSRI)) and an atypical antipsychotic or electroconvulsive therapy (ECT) in treating psychotic major depression. In several studies, monotherapy of SSRIs such as fluvoxamine has been shown to be effective in the treatment of psychotic major depression.</p> <p>Methods</p> <p>We report on a 36-year-old Japanese woman in whom fluvoxamine (a SSRI with sigma-1 receptor agonist) and sertraline (a SSRI with sigma-1 receptor antagonist) showed the opposite effects on psychotic symptoms in the treatment of psychotic major depression.</p> <p>Results</p> <p>Symptoms of depression and psychosis in the patient who was non-respondent to antipsychotic drugs improved after fluvoxamine monotherapy. At 3 years later, a switch to sertraline from fluvoxamine dramatically worsened the psychotic symptoms in the patient. Then, a switch back to fluvoxamine from sertraline improved these symptoms 1 week after fluvoxamine treatment.</p> <p>Conclusion</p> <p>Doctors should consider the monotherapy of sigma-1 receptor agonist fluvoxamine as an alternative approach to treating psychotic major depression.</p

    Diagnostically Challenging Epithelial Odontogenic Tumors: A Selective Review of 7 Jawbone Lesions

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    Considerable variation in the clinicopathologic presentation of epithelial odontogenic tumors can sometimes be confusing and increase the chance of misdiagnosis. Seven diagnostically challenging jawbone lesions are described. There were 2 cases of mistaken identity in our ameloblastoma file. One unicystic type, initially diagnosed and treated as a lateral periodontal cyst, showed destructive recurrence 6 years postoperatively. The other globulomaxillary lesion was managed under the erroneous diagnosis of adenomatoid odontogenic tumor and recurred 4 times over an 11-year period. This tumor was found in retrospect to be consistent with an adenoid ameloblastoma with dentinoid. The diagnosis of cystic squamous odontogenic tumor (SOT) occurring as a radicular lesion of an impacted lower third molar was one of exclusion. Of two unsuspected keratocystic odontogenic tumors, one depicted deceptive features of pericoronitis, while the other case has long been in our files with the diagnosis of globulomaxillary SOT. Two cases of primary intraosseous squamous cell carcinoma appeared benign clinically and exhibited unexpected findings; an impacted third molar began to erupt in association with the growth of carcinoma and another periradicular carcinoma showed dentinoid formation. Cases selectively reviewed in this article present challenging problems which require clinical and radiographic correlation to avoid potential diagnostic pitfalls

    Influence of socioeconomic factors on medically unnecessary ambulance calls

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    <p>Abstract</p> <p>Background</p> <p>Unnecessary ambulance use has become a socioeconomic problem in Japan. We investigated the possible relations between socioeconomic factors and medically unnecessary ambulance calls, and we estimated the incremental demand for unnecessary ambulance use produced by socioeconomic factors.</p> <p>Methods</p> <p>We conducted a self-administered questionnaire-based survey targeting residents of Yokohama, Japan. The questionnaire included questions pertaining to socioeconomic characteristics, dichotomous choice method questions pertaining to ambulance calls in hypothetical nonemergency situations, and questions on the city's emergency medical system. The probit model was used to analyze the data.</p> <p>Results</p> <p>A total of 2,029 out of 3,363 targeted recipients completed the questionnaire (response rate, 60.3%). Probit regression analyses showed that several demographic and socioeconomic factors influence the decision to call an ambulance. Male respondents were more apt than female respondents to state that they would call an ambulance in nonemergency situations (p < 0.05). Age was an important factor influencing the hypothetical decision to call an ambulance (p < 0.05); elderly persons were more apt than younger persons to state that they would call an ambulance. Possession of a car and hesitation to use an ambulance negatively influenced the hypothetical decision to call an ambulance (p < 0.05). Persons who do not have a car were more likely than those with a car to state that they would call an ambulance in unnecessary situations.</p> <p>Conclusion</p> <p>Results of the study suggest that several socioeconomic factors, i.e., age, gender, household income, and possession of a car, influence a person's decision to call an ambulance in nonemergency situations. Hesitation to use an ambulance and knowledge of the city's primary emergency medical center are likely to be important factors limiting ambulance overuse. It was estimated that unnecessary ambulance use is increased approximately 10% to 20% by socioeconomic factors.</p
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