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41.
Wheat grains are well known to be invaded by Fusarium spp. under field and storage conditions and contaminated with fumonisins. Therefore, determining Fusarium spp. and fumonisins in wheat grains is of prime importance to develop suitable management strategies and to minimize risk. Eighty-two stored wheat samples produced in Iran were collected from various supermarkets and tested for the presence of Fusarium spp. by agar plate assay and fumonisins by HPLC. A total of 386 Fusarium strains were isolated and identified through morphological characteristics. All these strains belonged to F. culmorum, F. graminearum, F. proliferatum and F.verticillioides. Of the Fusarium species, F. graminearum was the most prevalent species, followed by F. verticillioides, F. proliferatum and then F. culmorum. Natural occurrence of fumonisin B1 (FB1) could be detected in 56 (68.2%) samples ranging from 15-155 μg/kg, fumonisin B2 (FB2) in 35 (42.6%) samples ranging from 12-86 μg/kg and fumonisin B3 (FB3) in 26 (31.7%) samples ranging from 13-64 μg/kg. The highest FB1 levels were detected in samples from Eilam (up to 155 μg/kg) and FB2 and FB3 in samples from Gilan Gharb (up to 86 μg/kg and 64 μg/kg). 相似文献
42.
OBJECTIVES: Lipid biomarkers are integral in the assessment of dyslipidemia and cardiovascular risk, conditions that have become increasingly prevalent in pediatric populations. A comprehensive set of pediatric reference intervals for traditional or recently established lipid analytes is not currently available. DESIGN AND METHODS: 525 outpatient samples from a pediatric population were categorized into five age groups ranging from 0 to 20 years of age. Groups were further partitioned by gender. Serum or plasma samples were analyzed on the VITROS 5,1 FS Chemistry System for cholesterol and triglycerides by dry-film methods, direct HDL-C and LDL-C by selective detergent elimination, and apolipoproteins AI and B by immunoturbidimetry. Reference intervals were established by non-parametric methods at the 2.5th and 97.5th percentiles. RESULTS: Lipid levels show age- and gender-related differences, particularly during the first year of life and in young adults following puberty. Concentrations of total cholesterol, LDL-C, and apo B were lowest in the 12 months after birth and remained relatively constant throughout childhood, but decreased for males in early adulthood. Triglyceride levels increased gradually throughout childhood and adolescence, and along with cholesterol, the upper limits of these intervals exceeded the recommended concentrations of lipid levels in children. For HDL-C and apo AI, no age- or sex-related differences were found until after puberty when values for males decreased slightly. CONCLUSIONS: Our current reference intervals in children and adolescents provide an important update for lipid markers and suggest earlier incidence of hypercholesterolemia when compared to previous ranges. Increased profiling of lipids is anticipated, and these will aid in the early assessment of cardiovascular risk in pediatric populations. 相似文献
43.
OBJECTIVE: To determine the prevalence of lipid abnormalities at different times and to determine the influence of both the disease and corticosteroid therapy on lipid abnormalities in pediatric patients with systemic lupus erythematosus (SLE). METHODS: Lipid measurements were obtained in an inception cohort of 139 pediatric patients with SLE (114 females). Fasting levels of total cholesterol, triglycerides, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol in the SLE patients were compared with those in age- and sex-matched control subjects. Disease activity levels and medication dosages were obtained at the time of lipid measurements. RESULTS: At the time of diagnosis, the mean levels of total cholesterol, LDL cholesterol, and triglycerides were highest, whereas the mean levels of HDL cholesterol were lowest. The percentage of patients with abnormal triglyceride values was highest at diagnosis, decreased at year 1, and then remained relatively constant thereafter. The mean total cholesterol and LDL cholesterol levels decreased at year 1 as compared with the time of diagnosis and then remained relatively constant. The lowest mean HDL cholesterol levels were found at the time of diagnosis, and these values rose with time. Comparison of lipid levels at different prednisone dosages and disease activity levels revealed that changes in triglyceride levels were mainly associated with changes in disease activity, changes in both total cholesterol and LDL cholesterol levels were associated with changes in the prednisone dosage and not disease activity, and low levels of HDL cholesterol were associated with active SLE, whereas the prednisone dosage was associated with increased levels of HDL cholesterol. CONCLUSION: Factors intrinsic to SLE appear to alter lipid levels. Control of SLE may be the most important factor in improving abnormal lipid profiles, and paradoxically, prednisone therapy may improve abnormal lipid levels. 相似文献
44.
Animal models of cognitive dysfunction 总被引:4,自引:0,他引:4
Tayebati SK 《Mechanisms of ageing and development》2006,127(2):100-108
The increased life expectancy in industrialised countries in the last half century has also brought to a greater incidence of neurological disorders, including neurodegenerative diseases and developing in a rather long time. In this respect, Alzheimer's disease (AD), for the large incidence, and the dramatic loss of autonomy caused by its cognitive and behavioural symptoms represents one of the main challenges of modern medicine. Although AD is a typical human disease and probably includes several nosographic entities, the use of animal models may contribute to understand specific aspects of pathophysiology of the disease. The most widely used animal models are rodents and non-human primates. In this review different animal models characterised by impaired cognitive functions are analysed. None of the models available mimics exactly cognitive, behavioural, biochemical and histopathological abnormalities observed in neurological disorders characterised by cognitive impairment. However, partial reproduction of neuropathology and/or cognitive deficits of Alzheimer's disease (AD), vascular dementia and dementia occurring in Huntington's and Parkinson's diseases, or in other neurodegenerative disorders may represent a basis for understanding pathophysiological traits of these diseases and for contributing to their treatments. 相似文献
45.
46.
Kopp R Mottaghy K Kirschfink M 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2002,48(6):598-605
In vitro studies with miniaturized rotating circuits and heparinized human blood, as well as long-term extracorporeal membrane oxygenation with either heparin coated (HBS) or uncoated surfaces connected to adult sheep, were performed comparing the impact on complement activation in blood and on surfaces. Analysis of surface bound complement proteins revealed significantly reduced binding of activated C3 and C5b-9 to HBS in vitro, compared with uncoated surfaces, which was probably due to more HBS bound complement inhibitors (C1-Inhibitor, factor H) being present. This was reflected by significantly reduced activation of the alternative pathway (C3bBbP) and terminal complex (SC5b-9) by HBS but slightly increased levels of classic pathway complex (C1rs-C1-inhibitor). These results were confirmed during in vivo study by analysis of hemolytic complement function, activation specific C3 derived split products, and surface bound complement proteins. Increased binding of complement regulators to HBS appears to effectively reduce complement activation by biomaterials, leading to improved long-term biocompatibility. 相似文献
47.
Objective
Examine the effect of stimulus duration, intensity and level of muscle contraction on the inhibitory responses evoked by electrical stimuli in human jaw-closing muscles applied to the right mental nerve.Design
The inhibitory jaw-reflexes, short-latency (ES1) and long-latency (ES2), were recorded in the surface electromyogram (EMG) of masseter and temporalis muscles in 16 healthy subjects. Three stimulus durations (1 ms single square-wave pulse, 10 and 450 ms square-wave pulse train), two stimulus intensities adjusted to perceived intensity of 3 (non-painful) and 7 (distinct painful) on a 0–10 verbal rating scale were applied to the right mental nerve while the subject was biting at 25% and 50% of the maximal voluntary contraction (MVC).Results
The magnitude of suppression in the ES2 evoked by 1 and 10 ms stimuli was dependent on stimulus intensity (P < 0.002 and P < 0.001, respectively) but not contraction level. However, ES1 could not be observed in most of the recordings. There were significant decreases evoked by the 450 ms stimuli in RMS–EMG values in the 400–500 ms compared with the pre-stimulus interval (P < 0.001) which was dependent on contraction level (P < 0.01) but not on stimulus intensity (P = 0.486).Conclusions
The present results suggest that the ES2 reflex response is associated with the duration of the electrical stimuli, the intensity level but not the contraction level. In contrast, the inhibitory effects of ultra-long stimuli (450 ms) are not specifically related to the intensity level suggesting that this is a non-nociceptive response. 相似文献48.
Lu J Zello GA Randell E Adeli K Krahn J Meng QH 《Clinica chimica acta; international journal of clinical chemistry》2011,412(3-4):286-291
BackgroundA high anion gap in diabetic ketoacidosis (DKA) suggests that some unmeasured anions must contribute to the generation of the anion gap. We investigated the contribution of d-lactate to the anion gap in DKA.MethodsDiabetic patients with and without DKA and high anion gap were recruited. Plasma d-lactate was quantified by HPLC. Plasma methylglyoxal was assayed by liquid chromatography-tandem mass spectrometry.ResultsThe plasma fasting glucose, β-hydroxybutyrate, and blood HbA1c levels were highly elevated in DKA. Plasma anion gap was significantly increased in DKA (20.59 ± 6.37) compared to either the diabetic (7.50 ± 1.88) or the control group (6.53 ± 1.75) (p < 0.001, respectively). Moreover, plasma d-lactate levels were markedly increased in DKA (3.82 ± 2.50 mmol/l) compared to the diabetic (0.47 ± 0.55 mmol/l) or the control group (0.25 ± 0.35 mmol/l) (p < 0.001, respectively). Regression analysis demonstrated that d-lactate was associated with acidosis and anion gap (r = 0.686, p < 0.001).ConclusionsPlasma d-lactate levels are highly elevated and associated with metabolic acidosis and the high anion gap in DKA. Laboratory monitoring of d-lactate will provide valuable information for assessment of patients with DKA. 相似文献
49.
50.
Increased plasma methylglyoxal level, inflammation, and vascular endothelial dysfunction in diabetic nephropathy 总被引:1,自引:0,他引:1