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关键词： Yeast fermentate   Heat stress   Intestinal health   Cecal microbiome   Broiler chickens  

摘要： Heat stress, a common stressor in commercial poultry production, negatively affects growth and intestinal function of broiler chickens. Two experiments were conducted to evaluate the effects of a Saccharomyces cerevisiae-derived yeast fermentation product on cecal microbiome and indicators of intestinal barrier function in stressed broiler chickens. Yeast fermentate (YF) was added to the feed (1.25 kg/t) or drinking water (1.60 mL/L) for the duration of each experiment. In Exp. 1, 1-D-old male broiler chickens (N = 300 birds/treatment) were assigned to 1 of 3 treatments: stressed control (CS), stressed + YF in the feed (XS), and stressed + YF in the drinking water (AS). All birds were reared on re-used litter (d 0 to 42) and spray-vaccinated for coccidiosis (d 0). On d 18, all birds were spray-vaccinated for Newcastle/Bronchitis, then exposed to a 12 h concurrent heat stress and feed and water withdrawal. Cecal microbiome did not differ in composition or diversity between or within treatments on d 42. In Exp. 2, 1-D-old male broiler chickens (N = 40 birds/treatment) were reared to 43 d of age. Treatments included CS, XS, AS, non-stressed control (CN), non-stressed + YF in the feed (XN), and non-stressed + YF in the drinking water (AN). Stressed treatments were exposed to cyclic heat stress d 28 to 43 for 12 h/d. Blood samples collected on d 42 were used to analyze plasma chemistry, interleukin(IL)-1 alpha, IL-8, and alpha-1 -acid glycoprotein (alpha(1)-AGP);ileum samples collected on d 43 were used to assess histomorphology. Heat stress increased plasma creatine kinase (P < 0.001), uric acid (p < 0.001), sodium/potassium ratio (P < 0.001), and IL-1 alpha (P < 0.001), but decreased alkaline phosphatase (P = 0.04), potassium (P < 0.001), IL-8 (P < 0.001), and alpha(1)-AGP (P = 0.048). Plasma glutamate dehydrogenase was higher in birds fed the control diet or YF in the feed (P < 0.001) compared to birds supplemented with YF in the drinking water. Heat stress decreased

关键词： Aflatoxicosis   Biochemistry   Cattle   Feed poisoning   Oxidative stress   Postmortem changes   Toxicity  

摘要： Aflatoxicosis is a serious health condition resulted from aflatoxin (AF)-producing fungi. Major health threats resulted from AFs and reflect on the livestock industry with great economic losses. There are limited scientific evidences concerning the AFs in ruminant, therefore it is important to evaluate AFs health hazards in cattle. Here, we investigate biochemical, oxidative stress, and postmortem changes associated with unexpected acute bovine aflatoxicosis. Seventy-two cattle were suffered from aflatoxisocis. Depression and inappetence were predominant clinical findings of the diseased animals. Analysis of feedstuffs revealed presence of aflatoxin B1 (AFB1). The AF-intoxicated animals showed a significant increase in alanine amino transferase (ALT), aspartate amino transferase (AST), alkaline phosphatase (ALP), serum creatinine (SCr), catalase (CAT), and malondialdehyde (MDA) levels. Moreover, a significant decrease in total protein (TP), magnesium (Mg), and reduced glutathione (GSH) were also seen. Hepatomegaly, enlarged gallbladder as well as congestion of the intestine and kidney were observed. This study elucidates the critical and constructive measurements needed for the prevention of the AFs hazardous effects to livestock for the future control of AF outbreaks. Conducting series of diagnostic assays reflect the marked health condition alterations in the biochemical and antioxidant status of the AF-intoxicated cattle.

关键词： Chickpea   Wild relatives   Helicoverpa armigera   Antibiosis   Biochemical mechanism of resistance  

摘要： Efforts are being made to develop chickpea varieties with resistance to the pod borer, Helicoverpa armigera for reducing pesticide use and minimizing the extent of losses due to this pest. However, only low to moderate levels of resistance have been observed in the cultivated chickpea to this polyphagous pest. Hence, it is important to explore wild relatives as resistance sources to develop insect-resistant cultivars. Therefore, we studied different biochemical components that confer resistance to H. armigera in a diverse array of wild relatives of chickpea. Accessions belonging to wild relatives of chickpea exhibited high levels of resistance to H. armigera as compared to cultivated chickpea genotypes in terms of lower larval survival, pupation and adult emergence, decreased larval and pupal weights, prolonged larval and pupal developmental periods and reduced fecundity of the H. armigera when reared on artificial diet impregnated with lyophilized leaf powders. Amounts of proteins and phenols in different accessions of chickpea wild relatives were significantly and negatively correlated with larval weight, pupation and adult emergence. Phenols showed a negative correlation with pupal weight and fecundity, but positive correlation with pupal period. Total soluble sugars showed a negative correlation with larval period, but positive correlation with pupation and pupal weight, while tannins showed a positive correlation with larval weight, pupation and adult emergence. The flavonoid compounds such as chlorogenic acid, ferulic acid, naringin, 3,4-dihydroxy flavones, quercetin, naringenin, genistein, biochanin-A and formononetin that were identified through HPLC fingerprints, exhibited negative effects on survival and development of H. armigera reared on artificial diet impregnated with lyophilized leaf powders. The wild relatives with diverse mechanisms of resistance conferred by different biochemical components can be used as sources of resistance in chickpea breeding

关键词： Bikunin   CDG biomarker   CDG screening   Glycan mass spectrometry   Inherited GPI biosynthesis defects   TIEF  

摘要： Background: Glycosylation is one of the most complex post-translational modifications of proteins and lipids, notably requiring many glycosyltransferases, glycosidases and sugar transporters encoded by about 1-2% of all human genes. Deleterious variants in any of them may result in improper protein or lipid glycosylation, thus yielding the so-called 'congenital disorders of glycosylation' or CDG. Scope of review: We first review the current state of knowledge on the common blood and cellular glycoproteins used in the biochemical screening of CDG, as well as the emerging ones for an improved diagnosis. We then provide an overview of the current state-of-the-art methodologies ranging from gel electrophoresis to mass spectrometry to measure improper glycosylation. Finally, we discuss how additional tools such as metabolomics and microfluidics can be added to the current toolbox to better diagnose and delineate CDG. Major Conclusions: Combining several biochemical indicators and related methods is often required to cope with the large clinical heterogeneity of CDG and establish a definitive diagnosis. General significance: This review aims to critically present current available CDG biochemical biomarkers and dedicated methods in the context of highly diverse glycosylation pathways and related inherited diseases.

关键词： CHROMagar Orientation medium   Enterobacterales   presumptive identification   rapid biochemical tests  

摘要： Background The use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry is gradually spreading among large-scale laboratories;however, this method is impractical for small-scale laboratories. In laboratories without access to these rapid identification methods, problems related to them remain unsolved. In this study, we aimed to develop a rapid and inexpensive method to presumptively identifyEnterobacteralesusing CHROMagar Orientation medium. Methods The algorithm for presumptive identification ofEnterobacteriaceaeusing CHROMagar Orientation medium was based on our previous studies. Modified property tests for indole, lysine decarboxylase, ornithine decarboxylase, and hydrogen sulfide were performed to evaluate the differentiation of the bacterial species. Results Using the type strains and clinical isolates, it was possible to conduct the property tests at a low cost, within 4 hours. The spot indole test was performed without any nonspecific reactions for the bacteria forming colored colonies. The presumptive identification of bacteria was thereby possible within 24 hours after specimen submission. Conclusion All these results suggest that the rapid presumptive identification ofEnterobacteralesis possible with this new identification method using CHROMagar Orientation medium. This is therefore a prompt and economical method that can be used in routine laboratory work.

关键词： Non-steroidal anti-inflammatory drugs   Lemna minor   Daphnia magna   Photosynthetic pigments   Biochemical markers   Reproduction  

摘要： Among the most used non-steroidal anti-inflammatory drugs (NSAIDs), ketoprofen (KTF) assumes an important position. Nevertheless, its ecotoxicological effects in non-target organisms are poorly characterized, despite its use and frequency of occurrence in aquatic matrices. Thus, the aim of this study was to evaluate the possible toxicological effects of KTF contamination, in two freshwater species, Lemna minor and Daphnia magna, by measuring biochemical, physiological and population parameters. To attain this objective, both species were exposed to KTF at the same concentrations (0, 0.24, 1.2, 6 and 30 mu g/L). L. minor plants were exposed during 4 d to these levels of KTF, and the enzymatic activity (catalase (CAT), glutathione S-transferases (GSTs) and carbonic anhydrase (CA)), and pigments content (chlorophylls a, b and total and carotenoids) were analyzed to evaluate the toxicity of this drug. D. magna was acutely and chronically exposed to KTF, and enzymatic activities (CAT, GSTs and cyclooxygenase (COX)), the feeding rates, and reproduction traits were assessed. In L. minor, KTF provoked alterations in all enzyme activities, however, it was not capable of causing any alteration in any pigment levels. On the other hand, KTF also provoked alterations in all enzymatic activities in D. magna, but did not affect feeding rates and life-history parameters. In conclusion, exposure to KTF, provoked biochemical alterations in both species. However, these alterations were not reflected into deleterious effects on physiological and populational traits of L. minor and D. magna. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： Acetylcholinesterase activity   Calcium   Glucose   Glutamate-oxalacetate transaminase activity   Glutamate pyruvate transaminase activity   Phenthoate 50 EC  

摘要： The risks of the health-associated problems of pesticide-exposed non-target organisms are ubiquitous, therefore an emerging concern to strike the balance between benefit and risk factors. In the present study, by elucidating multiple biomarkers, the effects of Phenthoate 50 EC on the acute toxicity tests and different pathophysiological changes of common carp (Cyprinus carpio) fingerlings were studied in time- and concentration-dependent manners. The LC(50)of Phenthoate 50 EC for the fish was 7.39 (6.716-8.076) ppm at 96 h. As an indicator of neurotoxicity, compared to the control group, significant (P < 0.01) reduction in brain acetylcholinesterase (AChE) activity was observed, whereas plasma glutamate-oxalacetate transaminase (PGOT) and plasma glutamate pyruvate transaminase (PGPT) activities were increased significantly (P < 0.01) at the doses of 2.22 and 3.69 ppm of Phenthoate 50 EC, respectively. Histopathological changes in the insecticide-treated fish liver suggested the hepatic tissue damages, while alteration of the blood, gills and kidney morphology;progressive decrease (P < 0.05) in the serum calcium levels;and significantly (P < 0.01) decreased blood glucose level at 2.22 and 3.69 or 5.17 ppm of Phenthoate 50 EC demonstrated the oxidative stress and requirement of the up-surging energy demands due to the exposure of this organophosphate chemical. These results advice the modulation caused by this widely used agrochemical on the physiology of aquatic fauna by changing the enzymatic and biochemical indices at cellular level.

关键词： Iron oxides   Nitrous oxide   Nitrification   AOA   AOB  

摘要： Purpose Iron (Fe) oxides play an important role in regulating nitrification and N2O emissions, but there is very little study on the biological-chemical comprehensive effects of Fe oxides on nitrification and N2O emissions. Materials and methods A laboratory incubation experiment was performed to evaluate the effect of goethite addition on nitrification and N2O emissions from acidic and alkaline paddy soils. Results and discussion The cumulative N2O emissions from alkaline paddy soil were significantly higher than those from acidic paddy soil, no matter whether goethite had been added or not. Adding goethite decreased the average net rate of soil nitrification in acidic paddy soil by 33.2% in comparison with the treatment without adding goethite;however, adding goethite scarcely decreased the average net rate in alkaline paddy soil. Adding goethite increased the maximal N2O emissions by 85.6% in alkaline paddy soil, but had no obvious effect in acidic paddy soil. Adding goethite significantly increased the abundance of ammonia-oxidizing archaea (AOA) and bacteria (AOB)amoAgenes in both alkaline and acidic paddy soils. High-throughput pyrosequencing of 16S rRNA gene showed that adding goethite significantly increased the relative abundance ofNitrosomonadaceaein alkaline paddy soil and that the dominant species of AOB and AOA wereNitrosomonadaceaeandNitrososphaeraceae, respectively. Conclusions N2O emissions in alkaline paddy soil were higher than those in acidic paddy soil. The enhancement of N2O emissions by goethite was more significant in alkaline paddy soil than in acidic paddy soil. Goethite stimulated the abundance ofamoAgene (both of AOB and AOA) and participated in nitrification process via chemical reaction with intermediates.

关键词： appendicitis   C-reactive protein   inflammatory marker   white cell count  

摘要： Background Acute appendicitis is a common general surgical condition where diagnosis is predominantly clinical, with the aid of adjunct investigations. This study reviews the relationship between normal and elevated biochemical inflammatory markers, duration of symptoms and proven appendicitis. Methods A multicentre prospective observational study was performed across 27 centres and included a total of 949 patients with clinical suspicion of appendicitis, who had both white cell count (WCC) and C-reactive protein (CRP) recorded and underwent appendicectomy. Results A total of 90.4% of patients with raised WCC and CRP had appendicitis with a positive predictive value (PPV) of 0.9 and negative predictive value (NPV) of 0.4. Sensitivity and specificity of elevated WCC (sensitivity 66.5%, specificity 66.0%) and elevated CRP (sensitivity 77.3%, specificity 52.0%) lie within ranges identified by previous studies. A total of 39.8% of patients with normal CRP and WCC had appendicitis. Sensitivity and PPV for patients with elevated inflammatory markers were high until 48 h of symptoms (sensitivity 94%, PPV 0.87). NPV was elevated after 24 h (NPV 0.65 in patients with 24-48 h of symptoms, and 0.61 after 48 h), whilst those with symptoms less than 24 h had a lower NPV of 0.52. Conclusion Whilst elevated inflammatory markers are a helpful aid in the diagnosis of appendicitis, they should not be relied on by themselves. Nor can normal inflammatory markers be used to exclude appendicitis, even in those with prolonged duration of symptoms. The diagnosis of appendicitis should be guided by a combination of clinical judgement with the assistance of inflammatory markers.

关键词： Bream fillets   Spoilage bacteria   Protein degradation   Volatile organic compounds   Discoloration  

摘要： In this study, we evaluated the contributions of three bacteria (Pseudomonas versuta, Shewanella putrefaciens, and Aeromonas sobria) to the proteolysis, biogenic amines formation, volatile organic compounds accumulation, lipid oxidation, nucleotide catabolism, discoloration, and water migration of bream flesh during chilled storage. The results showed that P. versuta exhibited hydrolyzing activity against sarcoplasmic proteins, and all three strains could degrade myofibrillar proteins, specifically actin. The highest producer of putrescine was S. putrefaciens, which reached a maximum level 5.05 mg/kg after 14 days. Compared with the A. sobria group, hypoxanthine riboside degraded faster in samples inoculated with P. versuta or S. putrefaciens, A. sobria, P. versuta, and S. putrefaciens were responsible for the production of alcohol and aldehydes, whereas only S. putrefaciens produced thiophene and partial esters. Fish flesh inoculated with P. versuta, S. putrefaciens, and A. sobria presented slight green, yellow, and pink discoloration, respectively.