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Neuroscience Bulletin 2012年第5期28卷 517-531页

作者： S.Espíndola A Vilches-flores E.Hernández-Echeagaray Unidad de Biomedicina FES-I Universidad Nacional Autónoma de México Los Reyes IztacalaC. P. 54090 TlalnepantlaMéxico

Objective The aim of the present study was to determine the changes in the mRNA levels of neurotrophins and their receptors in the striatal tissue of mice treated with 3-nitropropionic acid （3-NP）. Methods At 1 and 48 h after the last drug administration, the mRNA expression of nerve growth factor, brain-derived neurotrophic factor, neurotrophin-3 and neurotrophin-4/5 as well as their receptors p75, TrkA, TrkB and Trkc, was evaluated using semi-quantitative （semi- Q） and real-time RT-PcR. β-actin mRNA and ribosomal 18S （18S rRNA） were tested as internal controls. Results 3-NP treatment did not affect mRNA expression of all neurotrophins and their respective receptors equally. Also, differences in neurotrophin and receptor mRNA expression were observed between semi-Q and real-time RT-PcR. Real-time RT-PcR was more accurate in evaluating the mRNA expression of the neurotrophins than semi-Q, and 18S rRNA was more reliable than β-actin as an internal control. conclusion Neurotrophins and their receptors expression is differentially affected by neuronal damage produced by inhibition of mitochondrial respiration with 3-NP treatment in low, sub-chronic doses in vivo.

关键词： neurotrophins striatum neurodegenerative disease PcR 18S 3-nitropropionic acid

comparing posture induced intraocular pressure variations in normal subjects and glaucoma patients

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International Journal of Ophthalmology(English edition) 2021年第3期14卷 399-404页

作者： Onyekachi jane Ireka chimdia E Ogbonnaya Obinna c Arinze Nneka Ogbu chimdi M chuka-Okosa Department of Ophthalmology Alex Ekwueme Federal University Teaching HospitalAbakalikiEbonyi State 48028Nigeria Department of Ophthalmology University of Nigeria Teaching HospitalItuku OzallaEnugu 01129Nigeria

AIM:To compare the posture-induced variations in intraocular pressure(IOP)between the primary open angle glaucoma(POAG)and non-glaucomatous ***:A case-controlled age matched study was conducted in 55 successive newly diagnosed POAG and 56 non-glaucomatous patients seen in glaucoma clinic and general outpatient eye clinic in the Alex Ekwueme University Teaching Hospital,*** IOPs of eligible correspondents were measured with Perkin’s hand-held tonometer in the sitting,supine flat and supine with pillow positions *** of IOP in each position was done after 15 min of assuming such ***:The IOP difference between the sitting and supine flat position was significantly higher in the POAG than non-glaucoma subjects(7.68±2.08 vs 4.03±0.13 mm Hg,Pce between the sitting and supine with pillow positions was 2.61±1.49 mm Hg for POAG and 1.44±0.70 mm Hg in non-glaucoma(Pce between supine flat and supine with pillow positions was 5.07±2.24 mm Hg in POAG and 2.59±0.66 mm Hg in non-glaucomatous patients(PcONcLUSION:Greater variations in posture induced IOP occurred in POAG patients than *** posture induced IOP variation is lowest in the sitting position and highest in the supine flat *** of posture induced IOP changes may be an important tool in the management of glaucoma.

关键词： primary open angle glaucoma non-glaucoma intraocular pressure sitting position supine position

Minimization of methabenzthiazuron residues in leaching water using amended soils and photocatalytic treatment with TiO_2 and ZnO

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Journal of Environmental Sciences 2014年第4期26卷 757-764页

作者： Jos Fenoll Pilar flores Pilar Hellín Joaquín Hern'andez Simón Navarro Department of Food Quality Murcia Institute of Agri-Food Research and Development Department of Agricultural chemistry Geology and Pedology School of Chemistry University of Murcia Campus Universitario de Espinardo

In the present work, potential groundwater pollution by methabenzthiazuron （MTBU） and the effect of three different amendments （composted sheep manure, composted pine bark and spent coffee grounds） on its mobility were investigated under laboratory conditions. The efficiency of ZnO and TiO2 suspensions in the photocatalytic degradation of MTBU in leaching water was also investigated. The relative and cumulative breakthrough curves were obtained from disturbed soil columns. The presence and/or addition of organic matter drastically reduced the movement of the herbicide. On other hand, photocatalytic experiments showed that the addition of ZnO and TiO2 strongly enhances the degradation rate of this herbicide compared with the results of photolytic experiments under artificial light. ZnO appeared to be more effective in MTBU oxidation than TiO2. The results obtained point to the interest of using organic wastes and heterogeneous photocatalysis for reducing the pollution of groundwater by pesticide drainage.

关键词： groundwater pollution organic amendment pesticide movement photocatalytic oxidation semiconductor oxides

Potato aphid Macrosiphum euphorbiae performance is determined by aphid genotype and not mycorrhizal fungi or water availability

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Insect Science 2017年第6期24卷 1015-1024页

作者： Alison jane Karley Matthew Emslie-Smith Alison Elizabeth Bennett Ecological Sciences The James Hutton Institute Invergowrie Dundee UK School of Biology University of St. Andrews St Andrews UK

Intra- and interspecific variation in plant and insect traits can alter the strength and direction of insect-plant interactions, with outcomes modified by soil biotic and abiotic conditions. We used the potato aphid （Macrosiphum euphorbiae Thomas） feeding on cultivated Solanum tuberosum and wild Solanurn berthaulti to study the impact of water availability and plant mutualistic arbuscular mycorrhizal （AM） fungi on aphid performance and susceptibility to a parasitoid wasp （Aphidius ervi Haliday）. Plants were grown under glass with live or sterile AM fungal spores and supplied with sufficient or reduced water supply. Plants were infested with 1 of 3 genotypes ofM. euphorbiae or maintained as aphidfree controls; aphid abundance was scored after 1 week, after which aphid susceptibility to A. ervi was assayed explanta. Solarium tuberosum accumulated c. 20% more dry mass than S. berthaultii, and root mass of S. berthaultii was smallest under reduced water supply in the presence of AM fungi. Aphid abundance was lowest on S. berthaultii and highest for genotype ＂2＂ aphids; genotype ＂1＂ aphid density was particularly reduced on S. berthaultii. Aphid genotype ＂1＂ exhibited low susceptibility to parasitism and was attacked less frequently than the other two more susceptible aphid genotypes. Neither AM fungi nor water availability affected insect performance. Our study suggests a fitness trade-offin M. euphorbiae between parasitism resistance and aphid performance on poor quality Solarium hosts that warrants further exploration, and indicates the importance of accounting for genotype identity in determining the outcome of multitrophic interactions.

关键词： Aphidius ervi arbuscular mycorrhizal fungi multitrophic interaction parasitism resistance Solanum spp.

characterization of Fusobacterium nucleatum ATcc 23726 adhesins involved in strain-specific attachment to Porphyromonas gingivalis

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International Journal of Oral Science 2016年第3期8卷 138-144页

作者： jane Park Bhumika Shokeen Susan K Haake Renate Lux School of Dentistry University of California at Los Angeles Los Angeles USA

Bacterial adherence is an essential virulence factor in pathogenesis and infection. Fusobacterium nucleatum has a central role in oral biofilm architecture by acting as a bridge between early Gram-positive and late Gram-negative colonizers that do not otherwise adhere to each other. In this study, we survey a key adherence interaction of F. nucleatum with Porphyromonas gingivalis, and present evidence that multiple fusobacterial adhesins have a role in the attachment of F. nucleatum ATcc 23726 to P. gingivalis in a highly strain-dependent manner. Interaction between these species displayed varying sensitivities to arginine, galactose and lactose. Arginine was found to hamper coaggregation by at least 62% and up to 89% with several P. gingivalis strains and galactose inhibition ranged from no inhibition up to 58% with the same P. gingivalis strains. Lactose consistently inhibited F. nucleatum interaction with these P. gingivalis strains ranging from 40% to 56% decrease in coaggregation. Among the adhesins involved are the previously described Fap2 and surprisingly, RadD, which was described in an earlier study for its function in attachment of F. nucleatum to Gram-positive species. We also provide evidence for the presence of at least one additional adhesin that is sensitive to arginine but unlike Fap2 and RadD, is not a member of the autotransporter family type of fusobacterial large outer membrane proteins. The strain-specific binding profile of multiple fusobacterial adhesins to P. gingivalis highlights the heterogeneity and complexity of interspecies interactions in the oral cavity.

关键词： adhesin bio?lm coaggregation Fusobacterium nucleatum Porphyromonas gingivalis

Shade shelters increase survival and photosynthetic performance of oak transplants at abandoned fields in semi-arid climates

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Journal of Forestry Research 2013年第1期24卷 23-28页

作者： claudia González-Salvatierra Ernesto Iván Badano Joel flores Juan Pablo Rodas División de ciencias Ambientales Instituto Potosino de Investigación Científica y TecnológicaA.C.Camino a la Presa San José 2055C.P. 78216San Luis PotosíS.L.P.México.

Forest restorations conducted in semiarid, seasonally dry climates must deal with the intense drought stress that affects tree seedlings during the dry season. Although this water deficit is the most commonly invoked source of mortality for seedlings, several other environmental factors may also preclude survival of transplants. For instance, it has been widely reported that excessive light reduces the efficiency of the photosynthetic apparatus, hence decreasing plant survival, but most seedling transplants in deforested areas are conducted under these light conditions. This study is focused in determining whether excessive light affects the photosynthetic performance and survival of Quercus coccolobifolia, a Mexican oak species, when their seedlings are transplanted in semiarid deforested areas. Further, this study tests the possibility of using artificial shade shelters to improve the ecophysiological performance and survival of seedlings. Oak seedlings were transplanted under full sunlight conditions and beneath artificial shade shelters of two different colors： white and black. To reduce water stress, and hence isolate the effects of light treatments, a drip irrigation system was implemented at each experimental plot. Seedling survival was monitored weekly for 128 days and photosynthetic performance was assessed by measuring chlorophyll fluorescence at three opportunities during the experiment. Sun-exposed seedlings showed lower photosynthetic performance and survival rates than those beneath shelters of both colors. These results suggest that sunlight damage can reduce seedling survival when they are transplanted in exposed sites, and that shade shelters can improve the success of forest restoration programs in semiarid climates.

关键词： chlorophyll fluorescence light stress photoinhibition reforestation forest restoration

cytotoxic effect of Spirulina platensis extracts on human acute leukemia Kasumi-1 and chronic myelogenous leukemia K-562 cell lines

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Asian Pacific Journal of Tropical Biomedicine 2017年第1期7卷 14-19页

作者： Flor Yohana flores Hernandez Sanghamitra Khandual Inocencia Guadalupe Ramírez López center for Investigation and Assistance in Technology Design for State of JaliscoC.P.45019ZapopanJaliscoMexico

Objective: To evaluate the cytotoxic effects of Spirulina platensis extracts on acute leukemia Kasumi-1 and chronic leukemia K-562 cancer cell ***: Various concentrations of Spirulina platensis extracts(0.25–50.00 mg/m L)obtained with different solvents were used to treat cell lines for 72 h. For cytotoxic effect studies, cell viability test with trypan blue solution, MTT assay and microscopic cytomorphological assessment were ***: Spirulina extract obtained with 70% ethanol showed significant cytotoxicity in K562 and Kasumi-1 cell lines. With trypan blue solution, Ic_(50) values were found to be4.64 mg/m L for K-562 and 3.68 mg/m L for Kusumi-1 cell lines. Spirulina aqueous extract also showed cytotoxicity with trypan blue method, at a slightly higher dose; where Ic_(50) values were 12.68 mg/m L for K-562 and 2.13 mg/m L for Kusumi-1 cell lines. The Ic_(50) values were found 0.40 mg/m L for K-562 and 0.31 mg/m L for Kusumi-1 cell lines for the 70% ethanol extract according to the MTT assay. Spirulina extract obtained with water also showed cytotoxicity but the dose was a little higher where Ic_(50) values were15.77 mg/m L for K-562 and 9.44 mg/m L for Kusumi-1 cell lines. The effect of cytotoxicity with ethanol extract is quite comparable with that observed for cyclophosphamide, which is a chemical used as anticancer ***: The cytotoxicity exhibited by Spirulina extract to cancer cell lines might be due to the presence of phytopigments(carotenoids, chlorophyll, phycocyanin) as well as polysaccharides that were reported previously as constituents of the extract. So crude extracts of Spirulina can be used as a source to develop anticancer drugs.

关键词： Leukemia cytotoxicity Spirulina carotenoids

control Alternatives for Damping-Off in Tomato Seedling Production

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Phyton-International Journal of Experimental Botany 2019年第3期88卷 325-333页

作者： A.c.Michel-Aceves J.F.Díaz-Nájera R.Ariza-flores M.A.Otero-Sánchez R.Escobar-Martínez c.H.Avendaño-Arrazate centro de Estudios Profesionales del colegio Superior Agropecuario del Estado de Guerrero Av.Vicente Guerrero No.81Colonia CentroIgualaGuerreroC.P.40000México Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias(INIFAP)Campo Experimental IgualaCarr.Iguala-TuxpanKm.2.5 IgualaGuerreroMéxico INIFAP-campo Experimental Rosario Izapa.carr.Tapachula-cacahoatán Tuxtla chicoChiapasC.P.30870México

In two tomato genotypes,we assessed control alternatives for damping-off with combinations of chemical fungicides and native/commercial strains of biological *** treatments consisting of 19 levels of mixing products,chemical fungicides,native strains and commercial products from biological control agents,and untreated treatment were used onto Ramsés and Toro *** were distributed on an incomplete block design in divided plots arrangement,where genotypes constitute the larger ones and the 8-repetition mixed products,the smaller *** 180 mL of fungal complexes,made of spores and mycellium Fusarium-solani(2×106 UFc),Rhizoctonia-solani(1×106 UFc),Phytophthora-capsici(1×105 UFc)and Sclerotium-rolfsii(mycellium-sclerotia)on each seedling trays,made inoculation *** mixtures of(Bacillus spp.+Streptomyces spp.+Trichoderma spp.)+(Propamocarb+Fosetyl);(Bacillus spp.+Streptomyces spp.+Trichoderma spp.)+(Metalaxyl+chlorothalonil);Pseudomonas fluorescens+Streptomyces+Micromonospore+Sporideamium+Aminoacidos,Péptidos,carbohidratos)+(Propamocarb+Fosetyl);the native strain of Trichoderma asperellum+(Propamocarb+fosetil)and the native strains Trichoderma asperellum+Bacillus subtilis,diminished damping-off,prevented its appearance and had most significant agronomic *** contrast to this,combination of(Mancozeb)+(Free iodine)+(Metalaxyl+chlorothalonil)+(Methyl thiophanate)produced some toxicity in the *** addition,Ramsés presented the best agronomic parameters,while Toro had the utmost fresh and dry weight in root.

关键词： Trichoderma harzianum T.lignorum biological control

classifying Abdominal Fat Distribution Patterns byUsing Body Measurement Data

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computer Modeling in Engineering & Sciences 2021年第3期126卷 1189-1202页

作者： Jingjing Sun Bugao Xu jane Lee Jeanne H.Freeland-Graves Department of Biomedical Engineering University of TexasAustinTX 78712USA Department of computer Science and Engineering University of North TexasDentonTX 76201USA Department of Nutritional Sciences University of TexasAustinTX 78712USA

This study aims to explore new categorization that characterizes the distribution clusters of visceral and subcutaneous adipose tissues(VAT and SAT)measured by magnetic resonance imaging(MRI),to analyze the relationship between the VAT-SAT distribution patterns and the novel body shape descriptors(BSDs),and to develop a classifier to predict the fat distribution clusters using the *** the study,66 male and 54 female participants were scanned by MRI and a stereovision body imaging(SBI)to measure participants’abdominal VAT and SAT volumes and the BSDs.A fuzzy c-means algorithm was used to form the inherent grouping clusters of abdominal fat distributions.A support-vector-machine(SVM)classifier,with an embedded feature selection scheme,was employed to determine an optimal subset of the BSDs for predicting internal fat distributions.A fivefold cross-validation procedure was used to prevent over-fitting in the *** classification results of the BSDs were compared with those of the traditional anthropometric measurements and the Dual Energy X-Ray Absorptiometry(DXA)*** clusters were identified for abdominal fat distributions:(1)low VAT and SAT,(2)elevated VAT and SAT,(3)higher SAT,and(4)higher *** cross-validation accuracies of the traditional anthropometric,DXA and BSD measurements were 85.0%,87.5% and 90%,*** to the traditional anthropometric and DXA measurements,the BSDs appeared to be effective and efficient in predicting abdominal fat distributions.

关键词： Abdominal fat distribution body shape descriptor SVM classifier

Students’ perception of effective clinical teaching and teacher behaviour

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Open Journal of Nursing 2013年第1期3卷 63-70页

作者： Ijeoma L. Okoronkwo jane-Lovena Onyia-pat mary-Ann E. Agbo Pat U. Okpala Afam c. Ndu Department of Nursing Sciences University of Nigeria Enugu Campus Enugu Nigeria

Learning in the clinical environment is an integral part of nursing education programme. In tertiarybased nursing courses, students spend time learning in the clinical setting as they do in their classroombased studies. The purpose of this study was to explore teaching skills considered by undergraduate student nurses as effective in the clinical setting as well as qualities that make a clinical teacher effective. A descriptive design was employed using questionnaires to collect data. Respondents comprised year four undergraduate student nurses admitted through direct entry (DE) and university matriculation examination (UME) results. Using validated structured questionnaire, data were collected from 101 students who had completed their six months consolidated clinical experience on their perception of teaching skills and teacher qualities considered effective in the clinical setting. Data were analyzed using both descriptive and inferential statistics. Specifically, frequencies, percentage and standard deviation were used for descriptive analysis of scores while chi square and Mann-Whitney tests were used to test the mean differences in the teaching skills and to test whether there was a significant difference in their perception of teacher behaviours respectively at 0.05 level of significance. The result showed that having both clinical (professional) and teaching knowledge were the most important teaching skills for effective clinical teaching. Five qualities ranked by students as teacher behaviours important for effective teaching include being honest with students, motivation to teach, willingness to listen and using good communication skills, supervising students effectively and being positive role model. These factors could be considered when recruiting future clinical teachers and when planning inservice education programmes for clinical teachers to promote student learning.

关键词： clinical Teaching in Nursing Direct Entry and University Matriculation Examination Students Student Nurses’ Perceptions Teachers’ Behaviours