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Influence of nitrogen sources on growth and mycotoxin production by isolates of Pyrenophora tritici-repentis from wheat

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The Crop Journal 2016年第2期4卷 119-128页

作者： Noureddine Bouras michael d.Holtz Reem Aboukhaddour Stephen E.Strelkov department of Agricultural Food and Nutritional Science410 Agriculture/Forestry CentreUniversity of Alberta Laboratoire de Biologie des Systemes Microbiens(LBSM) Ecole Normale Superieure de KoubaAlgiersAlgeria departement de Biologie Faculte des Sciences de la Nature et de la Vie et Sciences de la TerreUniversite de Ghardaia Field Crop development Centre Alberta Agriculture and Food

The fungus Pyrenophora tritici-repentis(died.) drechs. infects the leaves and kernels of wheat,causing tan spot and red smudge, respectively. Isolates of P. tritici-repentis have been reported to be both phytopathogenic and mycotoxigenic. This research investigates the influence of nitrogen sources on growth and production of mycotoxins by eight different isolates of P. tritici-repentis. A synthetic agar medium(SAM) was used with different nitrogen sources, both inorganic [(NH4Cl, NH4NO3and(NH4)2SO4)] and organic(L-alanine, L-histidine, and L-lysine), at a concentration of 37.5 mmol L-1. Individual isolates exhibited different growth rates that varied according to the nitrogen source added to the medium. The choice of nitrogen source also had a major effect on production of the mycotoxins emodin, catenarin and islandicin. The highest concentrations of emodin, 54.40 ± 4.46 μg g-1, 43.07 ± 23.39 μg g-1and28.91 ± 4.64 μg g-1of growth medium, were produced on the complex medium(V8-potato dextrose agar) by the isolates Alg-H2, 331-2 and TS93-71 B, respectively. A relatively high concentration of emodin also was produced by isolates Az35-5(28.29 ± 4.71 μg g-1of medium)and TS93-71B(27.03 ± 4.09 μg g-1of medium) on synthetic medium supplemented with L-alanine. The highest concentrations of catenarin(174.54 ± 14.46 μg g-1and 104.87 ±6.13 μg g-1of medium) were recorded for isolates TS93-71 B and Alg-H2 on synthetic medium supplemented with L-alanine and NH4 Cl, respectively. The highest concentration of islandicin(4.64 ± 0.36 μg g-1medium) was observed for isolate 331-2 in the presence of L-lysine. There was not a close relationship between mycelial growth and mycotoxin production by the fungal isolates. This is the first report on the influence of nitrogen sources on the production of mycotoxins by P. tritici-repentis.

关键词： Catenarin Emodin Islandicin Nitrogen source Tan spot Triticum aestivum

Molecular genetics of ependymoma

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Chinese Journal of Cancer 2011年第10期30卷 669-681页

作者： Yuan Yao Stephen C. Mack michael d. Taylor division of Neurosurgery Arthur and Sonia LabattBrain Tumour Research Centre Hospital for Sick Children TorontoOntario Canada department of Laboratory Medicine and Pathobiology University of Toronto Toronto Ontario Canada.

Brain tumors are the leading cause of cancer death in children,with ependymoma being the third most common and posing a significant clinical *** mechanism of pathogenesis,reliable prognostic indicators,and effective treatments other than surgical resection have all remained *** recently,ependymoma research was hindered by the small number of tumors available for study,low resolution of cytogenetic techniques,and lack of cell lines and animal *** heterogeneity,which manifests as variations in tumor location,patient age,histological grade,and clinical behavior,together with the observation of a balanced genomic profile in up to 50% of cases,presents additional challenges in understanding the development and progression of this *** these difficulties,we have made significant headway in the past decade in identifying the genetic alterations and pathways involved in ependymoma tumorigenesis through collaborative efforts and the application of microarray-based genetic(copy number) and transcriptome profiling *** characterization of ependymoma unraveled distinct mRNA-defined subclasses and led to the identification of radial glial cells as its cell type of *** review summarizes our current knowledge in the molecular genetics of ependymoma and proposes future research directions necessary to further advance this field.

关键词：分子遗传学室管膜肿瘤发生发病机制手术切除动物模型遗传变异遗传特性

Epidemio-Clinical Aspects of Ecrectile dysfunction in Type 2 diabetics at Abeche Chu

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Open Journal of Urology 2024年第2期14卷 50-60页

作者： Vadandi Valentin Mahamat Ali Mahamat Minguemadji Allah Siyangar Temga Ouang michael Vounouzia Barthelemy Ndormadjita Allah Siyangar Abdelmahamoud Chene Konan Paul Gerard Rimtebaye Kimassoum Urology department University Hospital Center Abeche Chad Urology department University Hospital of National Reference N’Djamena Chad Urology department University Hospital of Renaissance N’Djamena Chad Urology department University Hospital Center Abidjan Cote d’Ivoire

Introduction: Erectile dysfunction (Ed) is a frequent complication of diabetes and more frequently affects type 2 diabetics. It is often unrecognised or its management is delayed because it is often overshadowed by other complications. The aim of our study was to describe the epidemiological and clinical aspects of Ed. Patients and Method: This was a descriptive cross-sectional study over an 8-month period from April to december 2021, of type 2 diabetic subjects with erectile dysfunction (Ed) seen at the University Hospital of Abeche. Erectile function was assessed using the International Index of Erectile Function (IIEFS5). Results: Out of a total of 112 patients with type 2 diabetes, 64 agreed to take part in the study. Only 40 patients correctly completed the survey form. Of these, 34 (85%) had erectile dysfunction. On average, our patients were over 49.4 years old, and 55.9% of them had had diabetes for more than 10 years. Erectile dysfunction had affected the social life of 21 patients (61.76% of cases) and 28 (82.35%) had not been informed by a healthcare professional. Most of them, 31 cases or 91.17%, had never told their GP about their erectile dysfunction. The patients who thought that diabetes had an influence on their erectile dysfunction represented 74%. diabetes was poorly controlled in 22 patients (64.70%). According to the International Index of Erectile Function (IIEF5), 85% of diabetic patients suffer from erectile dysfunction, including 28.6% with severe erectile dysfunction, 35.7% with moderate erectile dysfunction and 14.3% with mild erectile dysfunction. Erectile dysfunction was significantly more frequent in diabetics with arterial hypertension and poor diabetic control. Conclusion: The hospital prevalence of erectile dysfunction in our patients is high. Early detection of this disorder therefore remains a challenge to be met in order to organise better psychological and drug treatment.

关键词： diabetes Erectile dysfunction Screening

Interobserver error in grassland vegetation surveys:sources and implications

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Journal of Plant Ecology 2020年第5期13卷 641-648页

作者： Lloyd W.Morrison Sherry A.Leis michael d.deBacker department of Biology Missouri State University901 S.National AvenueSpringfieldMO 65897USA National Park Service Heartland Inventory and Monitoring ProgramWilson’s Creek National Battlefield6424 W.Farm Road 182RepublicMO 65738USA

Aims Observer error is an unavoidable aspect of vegetation surveys involving human *** quantified four components of interobserver error associated with long-term monitoring of prairie vegetation:overlooking error,misidentification error,cautious error and estimation *** also evaluated the association of plot size with pseudoturnover due to observer error,and how documented pseudochanges in species composition and abundance compared with recorded changes in the vegetation over a 4-year *** This study was conducted at Tallgrass Prairie National Preserve,*** sites contained 10 plots;each plot consisted of a series of four nested frames(0.01,0.1,1 and 10 m^(2)).The herbaceous species present were recorded in each of the nested frames,and foliar cover was visually estimated within seven cover categories at the 10 m^(2)spatial scale *** hundred total plots(30 sites)were surveyed,and 28 plots selected at random were resurveyed to assess observer *** surveyors worked in teams of *** Findings At the 10 m^(2)spatial scale,pseudoturnover resulting from overlooking error averaged 18.6%,compared with 1.4%resulting from misidentification error and 0.6%resulting from cautious *** resulting from overlooking error increased as plot size decreased,although relocation error likely played a *** change in species composition over a 4-year interval(excluding potential misidentification error and cautious error)was 30.7%,which encompassed both pseudoturnover due to overlooking error and actual *** a documented overlooking error rate of 18.6%,this suggests the actual change for the 4-year period was only 12.1%.For estimation error,26.2%of the time a different cover class was *** the 4-year interval,46.9%of all records revealed different cover classes,suggesting that 56%of the records of change in cover between the two time periods were due to observer error.

关键词： cautious error estimation error misidentification error observer error overlooking error pseudoturnover

The role of microglia versus peripheral macrophages in maladaptive plasticity after nerve injury

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Neural Regeneration Research 2021年第6期16卷 1202-1203页

作者： Thomas A.Szabo-Pardi Nilesh M.Agalave michael d.Burton Neuroimmunology and Behavior Laboratory Department of NeuroscienceSchool of Behavioral and Brain SciencesCenter for Advanced Pain StudiesUniversity of Texas at DallasRichardsonTXUSA

Microglia and macrophages in the development of maladaptive plastic changes after peripheral nerve injury:Microglia and macrophages encompass the innate immune response to injury in the central and peripheral nervous systems,respectively,and are intimately involved in the pathogenesis of maladaptive changes(Tsuda,2019).These dynamic cells can influence neuronal activity in active and quiescent *** findings argue that peripheral macrophages facilitate the development of nerve injury-induced neuropathic pain,as opposed to central microglia(Lopes et al.,2017;Yu et al.,2020).

关键词： al. injury peripheral

differences in characteristics of patients with and without known risk factors for hepatocellular carcinoma in the United States

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World Journal of Gastroenterology 2007年第5期13卷 781-784页

作者： Jon d dorfman Richard Schulick michael A Choti Jean-Francois H Geschwind Ihab Kamel michael Torbenson Paul J Thuluvath department of Surgery The Johns Hopkins University School of Medicine Baltimore MD 21205 United States department of Radiology The Johns Hopkins University School of Medicine Baltimore MD 21205 United States department of Pathology The Johns Hopkins University School of Medicine Baltimore MD 21205 United States department of Medicine The Johns Hopkins University School of Medicine Baltimore MD 21205 United States

AIM： To examine the clinical characteristics of a subgroup of patients with hepatocellular carcinoma （HCC） and compare them to those with known risk factors. METHOdS： We used the HCC database of 306 patients seen at our institution from January 1, 1995 to december 31, 2001. Of the 306 patients, 63 （20%, group 1） had no known risk factors （hepatitis C virus, hepatitis B virus, alcohol, hemochromatosis or cirrhosis from any cause） and 243 （group 2） had one or more risk factors. RESULTS： The median age was similar in both groups, but there were disproportionate numbers of younger （〈 30 years old）, older （〉 80 years） patients, women （33% vs 18%）, and Caucasians （81% vs 52%） in group 1 as compared to group 2. There were fewer Asians （2% vs 11%） and African Americans （13% vs 27%） in group 1. Abdominal pain （70% vs 37%） was more common while gastrointestinal bleeding （0% vs 11%） and ascites （4% vs17%） were less common in group i compared to group 2. Group 1 had larger tumor burden （median size 9.4 cm vs 5.7 cm） at the time of presentation, but there were no differences in the site （right, left or bilateral lesions）, or number of tumors between the two groups. CONCLUSION： HCC patients without identifiable risk factors have different characteristics and clinical presentation compared to those with known risk *** of cirrhosis and larger tumor burden may explain the differences in the presenting symptoms.

关键词： Hepatocellular carcinoma Patient charaocteristics Risk factors

Validation of the age-adjusted shock index for pediatric casualties in Iraq and Afghanistan

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Military Medical Research 2021年第1期8卷 17-24页

作者： Camaren M.Cuenca Matthew A.Borgman michael d.April Andrew d.Fisher Steven G.Schauer JUS Army Institute of Surgical Research 3698 Chambers PassJBSA Fort Sam HoustonSan AntonioTX 78234-7767USA Brooke Army Medical Center JBSA Fort Sam HoustonSan AntonioTXUSA Uniformed Services University of the Heath Sciences BethesdaMDUSA Texas Army National Guard AustinTXUSA department of Surgery UNM School of MedicineAlbuquerqueNMUSA 59th Medical Wing JBSA LacklandSan AntonioTXUSA

Background: Pediatric casualties account for a notable proportion of encounters in the deployed setting based on the humanitarian medical care mission. Previously published data demonstrates that an age-adjust shock index may be a useful tool in predicting massive transfusion and death in children. We seek to determine if those previous findings are applicable to the deployed, combat trauma ***: We queried the department of defense Trauma Registry(dOdTR) for all pediatric subjects admitted to US and Coalition fixed-facility hospitals in Iraq and Afghanistan from January 2007 to January 2016. This was a secondary analysis of casualties seeking to validate previously published data using the shock index, pediatric age adjusted. We then used previously published thresholds to determine patients outcome for validation by age grouping, 1–3 years(1.2), 4–6 years(1.2), 7–12 years(1.0), 13–17 years(0.9).Results: From January 2007 through January 2016 there were 3439 pediatric casualties of which 3145 had a documented heart rate and systolic pressure. Of those 502(16.0%) underwent massive transfusion and 226(7.2%) died prior to hospital discharge. Receiver operating characteristic(ROC) thresholds were inconsistent across age groups ranging from 1.0 to 1.9 with generally limited area under the curve(AUC) values for both massive transfusion and death prediction characteristics. Using the previously defined thresholds for validation, we reported sensitivity and specificity for the massive transfusion by age-group: 1–3(0.73, 0.35), 4–6(0.63, 0.60), 7–12(0.80, 0.57), 13–17(0.77, 0.62). For death, 1–3(0.75, 0.34), 4–6(0.66–0.59), 7–12(0.64, 0.52), 13–17(0.70, 0.57). However, negative predictive values(NPV) were generally high with all greater than ***: Within the combat setting, the age-adjusted pediatric shock index had moderate sensitivity and relatively poor specificity for predicting massive transfusion and death. Better scoring systems are needed to p

关键词： Pediatric Massive Transfusion Shock Index Age

Effects of quaternary ammonium chain length on the antibacterial and remineralizing effects of a calcium phosphate nanocomposite

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International Journal of Oral Science 2016年第1期8卷 45-53页

作者： Ke Zhang Lei Cheng michael d Weir Yu-Xing Bai Hockin HK Xu department of Orthodontics School of Stomatology Capital Medical University Biomaterials & Tissue Engineering division Department of EndodonticsPeriodontics and Prosthodontics School of Dentistry University of Maryland State Key Laboratory of Oral diseases West China Hospital of StomatologySichuan University Center for Stem Cell Biology & Regenerative Medicine School of Medicine University of Maryland department of Mechanical Engineering University of Maryland

Composites containing nanoparticles of amorphous calcium phosphate （NACP） remineralize tooth lesions and inhibit caries. A recent study synthesized quaternary ammonium methacrylates （QAMs） with chain lengths （CLs） of 3-18 and determined their effects on a bonding agent. This study aimed to incorporate these QAMs into NACP nanocomposites for the first time to simultaneously endow the material with antibacterial and remineralizing capabilities and to investigate the effects of the CL on the mechanical and biofilm properties. Five QAMs were synthesized： dMAPM （CL3）, dMAHM （CL6）, dMAddM （CL12）, dMAHdM （CL16）, and dMAOdM （CL18）. Each QAM was incorporated into a composite containing 20% NACP and 50% glass fillers. A dental plaque microcosm biofilm model was used to evaluate the antibacterial activity. The flexural strength and elastic modulus of nanocomposites with QAMs matched those of a commercial control composite （n = 6; P 〉 0.1）. Increasing the CL from 3 to 16 greatly enhanced the antibacterial activity of the NACP nanocomposite （P 〈 0.05）; further increasing the CL to 18 decreased the antibacterial potency. The NACP nanocomposite with a CL of 16 exhibited biofilm metabolic activity and acid production that were 10-fold lesser than those of the control composite. The NACP nanocomposite with a CL of 16 produced 2-log decreases in the colony-forming units （CFU） of total microorganisms, total streptococci, and mutans streptococci. In conclusion, QAMs with CLs of 3-18 were synthesized and incorporated into an NACP nanocomposite for the first time to simultaneously endow the material with antibacterial and remineralization capabilities. Increasing the C/reduced the metabolic activity and acid production of biofilms and caused a 2-log decrease in CFU without compromising the mechanical properties. Nanocomposites exhibiting strong anti-biofilm activity, remineralization effects, and mechanical properties are promising materials for tooth restorations that inhibit caries.

关键词： antibacterial nanocomposite calcium phosphate nanoparticles caries inhibition human saliva microcosm biofilm quaternary ammonium chain length

Summer egg diapause in a matchstick grasshopper synchronizes the life cycle and buffers thermal extremes

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Integrative Zoology 2018年第4期13卷 437-449页

作者： michael R.KEARNEY John dEUTSCHER Jacinta d.KONG Ary A.HOFFMANN School of BioSciences The University of MelbourneParkvilleAustralia

The phenological response is among the most important traits affecting a species’sensitivity to *** insects,strongly seasonal environments often select for a univoltine life cycle such that one seasonal extreme is avoided as an inactive *** understanding the underlying mechanisms for univoltinism,and the consequences of its failure,we can better predict insect responses to climate *** we combine empirical data and simulation studies to investigate the consequences of an unusual diapause mechanism in a parthenogenetic matchstick grasshopper,Warramaba virgo,from arid southern *** field body temperature measurements indicate that this species is a thermoconformer and our laboratory studies of the thermal response of feeding rate imply strong constraints on winter ***,the species exhibits no obligate winter diapause,and eggs can develop in 1 month under constant temperatures approximating the mean soil temperature at the time of oviposition(summer).We show that diurnal temperature cycles exceeding a peak of 36℃ inhibit egg development in summer,and that this is sufficient to prevent autumnal hatching of *** is also strongly retarded below 24℃.Microclimate-driven simulation studies of egg development show that these thermal responses provide robust maintenance of a univoltine life cycle,thereby resulting in survival of heat stress as an egg(due to limited developmental state)and avoidance of cold stress as a nymph and adult(due to overwintering in the soil as an egg).

关键词： egg diapause life cycle matchstick grasshopper phenology thermal extremes thermoregulation