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Whalen DA, Catchot AL, Gore J, Cook DR, Barton BT, Brown RL, Irby JT, Speights CJ. Impacts of Winter Annual Cover Crops and Neonicotinoid Seed Treatments on Arthropod Diversity in Mississippi Soybean. ENVIRONMENTAL ENTOMOLOGY 2022; 51:578-585. [PMID: 35452123 DOI: 10.1093/ee/nvac016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Indexed: 06/14/2023]
Abstract
Winter annual cover crops can be planted before soybean in Mississippi for many agronomic reasons. Incorporating winter annual cover crops into soybean production changes the seasonal hosts within fields. Some studies suggest that reducing tillage and using diverse species of cover crops can increase arthropod diversity and predator activity. Neonicotinoid seed treatments are often implemented to combat early season insect pests in soybean that follow cover crops, but negative effects on the environment such as reductions in biodiversity are often attributed to these compounds. We conducted an experiment to measure the effects on the diversity of the soybean epigeal and foliar communities when incorporating cover crops as well as insecticidal seed treatments into Mississippi soybean growing systems. Our results showed that legume cover crops had significant impacts on the epigeal community diversity of soybean planted behind them. These cover crops, especially hairy vetch, supported a more diverse foliar community before termination. To prevent increases in herbivorous arthropods, neonicotinoid seed treatments can be used without affecting epigeal predators such as beetles, ants, and spiders. The neonicotinoid seed treatments affected arthropod diversity, but the reductions were mainly caused by decreases in herbivorous pest insects that fed on treated soybean plants.
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Brown RL, Durbin J, Evans JM. Techniques for Testing the Constancy of Regression Relationships Over Time. ACTA ACUST UNITED AC 2018. [DOI: 10.1111/j.2517-6161.1975.tb01532.x] [Citation(s) in RCA: 549] [Impact Index Per Article: 91.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abstract
12 Ss were exposed to electropulse stimulation under 3 moisture treatments: dry, water immersion, and a fluid approximation of sweat. Touch threshold data were obtained under these conditions during the first half of the experiment and electropulse recognition responses during the second half. A significant threshold rise occurred with increased amounts of moisture on the skin. Similarly, recognition accuracy decreased but remained within a 90 to 100% range. Human engineering implications pertinent to a tactual communication system were discussed.
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Chen ZY, Rajasekaran K, Brown RL, Sayler RJ, Bhatnagar D. Discovery and confirmation of genes/proteins associated with maize aflatoxin resistance. WORLD MYCOTOXIN J 2015. [DOI: 10.3920/wmj2014.1732] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Maize (Zea mays L.) is one of the major crops susceptible to Aspergillus flavus infection and subsequent aflatoxin contamination. Many earlier studies indicated the roles of kernel proteins, especially constitutively expressed proteins, in maize resistance to A. flavus infection and aflatoxin production. In this review, we examined the past and current efforts in identifying maize genes and proteins from kernel, rachis, and silk tissues that may play an important role in resistance to A. flavus infection and aflatoxin contamination, as well as the efforts in determining the importance or involvement of them in maize resistance through biochemical, molecular and genetics studies. Through these studies, we gained a better understanding of host resistance mechanism: resistant lines appear to either express some stress-related and antifungal proteins at higher levels in endosperm, embryo, rachis and silk tissues before A. flavus infection or induce the expression of these proteins much faster compared to susceptible maize lines. In addition, we summarised several recent efforts in enhancing maize resistance to aflatoxin contamination using native genes from maize or heterologous and synthetic genes from other sources as well as from A. flavus. These efforts to either suppress A. flavus growth or aflatoxin production, have all shown some promising preliminary success. For example, maize plants transformed with an ?-amylase inhibitor protein from Lablab purpurea showed reduced aflatoxin levels by 56% in kernel screening assays. The antifungal potentials of transgenic maize plants expressing synthetic lytic peptides, such as cecropin-based D4E1 or tachyplesin-based AGM peptides with demonstrated anti-flavus activity (IC50 = 2.5 to 10 ?M), are yet to be assayed. Further investigation in these areas may provide a more cost-effective alternative to biocontrol in managing aflatoxin contamination in maize and other susceptible crops.
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An FP, Balantekin AB, Band HR, Beriguete W, Bishai M, Blyth S, Brown RL, Butorov I, Cao GF, Cao J, Carr R, Chan YL, Chang JF, Chang Y, Chasman C, Chen HS, Chen HY, Chen SJ, Chen SM, Chen XC, Chen XH, Chen Y, Chen YX, Cheng YP, Cherwinka JJ, Chu MC, Cummings JP, de Arcos J, Deng ZY, Ding YY, Diwan MV, Draeger E, Du XF, Dwyer DA, Edwards WR, Ely SR, Fu JY, Ge LQ, Gill R, Gonchar M, Gong GH, Gong H, Gornushkin YA, Gu WQ, Guan MY, Guo XH, Hackenburg RW, Hahn RL, Han GH, Hans S, He M, Heeger KM, Heng YK, Hinrichs P, Hor Y, Hsiung YB, Hu BZ, Hu LJ, Hu LM, Hu T, Hu W, Huang EC, Huang HX, Huang HZ, Huang XT, Huber P, Hussain G, Isvan Z, Jaffe DE, Jaffke P, Jetter S, Ji XL, Ji XP, Jiang HJ, Jiao JB, Johnson RA, Kang L, Kettell SH, Kramer M, Kwan KK, Kwok MW, Kwok T, Lai WC, Lai WH, Lau K, Lebanowski L, Lee J, Lei RT, Leitner R, Leung A, Leung JKC, Lewis CA, Li DJ, Li F, Li GS, Li QJ, Li WD, Li XN, Li XQ, Li YF, Li ZB, Liang H, Lin CJ, Lin GL, Lin SK, Lin YC, Ling JJ, Link JM, Littenberg L, Littlejohn BR, Liu DW, Liu H, Liu JC, Liu JL, Liu SS, Liu YB, Lu C, Lu HQ, Luk KB, Ma QM, Ma XB, Ma XY, Ma YQ, McDonald KT, McFarlane MC, McKeown RD, Meng Y, Mitchell I, Nakajima Y, Napolitano J, Naumov D, Naumova E, Nemchenok I, Ngai HY, Ngai WK, Ning Z, Ochoa-Ricoux JP, Olshevski A, Patton S, Pec V, Peng JC, Piilonen LE, Pinsky L, Pun CSJ, Qi FZ, Qi M, Qian X, Raper N, Ren B, Ren J, Rosero R, Roskovec B, Ruan XC, Shao BB, Steiner H, Sun GX, Sun JL, Tam YH, Tanaka HK, Tang X, Themann H, Trentalange S, Tsai O, Tsang KV, Tsang RHM, Tull CE, Tung YC, Viren B, Vorobel V, Wang CH, Wang LS, Wang LY, Wang LZ, Wang M, Wang NY, Wang RG, Wang W, Wang WW, Wang X, Wang YF, Wang Z, Wang Z, Wang ZM, Webber DM, Wei H, Wei YD, Wen LJ, Whisnant K, White CG, Whitehead L, Wise T, Wong HLH, Wong SCF, Worcester E, Wu Q, Xia DM, Xia JK, Xia X, Xing ZZ, Xu J, Xu JL, Xu JY, Xu Y, Xue T, Yan J, Yang CG, Yang L, Yang MS, Ye M, Yeh M, Yeh YS, Young BL, Yu GY, Yu JY, Yu ZY, Zang SL, Zhan L, Zhang C, Zhang FH, Zhang JW, Zhang QM, Zhang SH, Zhang YC, Zhang YH, Zhang YM, Zhang YX, Zhang ZJ, Zhang ZP, Zhang ZY, Zhao J, Zhao QW, Zhao YB, Zheng L, Zhong WL, Zhou L, Zhou ZY, Zhuang HL, Zou JH. Spectral measurement of electron antineutrino oscillation amplitude and frequency at Daya Bay. PHYSICAL REVIEW LETTERS 2014; 112:061801. [PMID: 24580686 DOI: 10.1103/physrevlett.112.061801] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Indexed: 06/03/2023]
Abstract
A measurement of the energy dependence of antineutrino disappearance at the Daya Bay reactor neutrino experiment is reported. Electron antineutrinos (ν¯(e)) from six 2.9 GW(th) reactors were detected with six detectors deployed in two near (effective baselines 512 and 561 m) and one far (1579 m) underground experimental halls. Using 217 days of data, 41 589 (203 809 and 92 912) antineutrino candidates were detected in the far hall (near halls). An improved measurement of the oscillation amplitude sin(2)2θ(13)=0.090(-0.009)(+0.008) and the first direct measurement of the ν¯(e) mass-squared difference |Δm(ee)2|=(2.59(-0.20)(+0.19))×10(-3) eV2 is obtained using the observed ν¯(e) rates and energy spectra in a three-neutrino framework. This value of |Δm(ee)2| is consistent with |Δm(μμ)2| measured by muon neutrino disappearance, supporting the three-flavor oscillation model.
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Ward E, Wiltshire JC, Detry MA, Brown RL. African American men and women's attitude toward mental illness, perceptions of stigma, and preferred coping behaviors. Nurs Res 2013; 62:185-94. [PMID: 23328705 PMCID: PMC4279858 DOI: 10.1097/nnr.0b013e31827bf533] [Citation(s) in RCA: 130] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Although research focused on African Americans with mental illness has been increasing, few researchers have addressed gender and age differences in beliefs, attitudes, and coping. OBJECTIVE The aim of this study was to examine African Americans' beliefs about mental illness, attitudes toward seeking mental health services, and preferred coping behaviors and whether these variables differ by gender and age. METHODS An exploratory, cross-sectional survey design was used. Participants were 272 community-dwelling African Americans aged 25-72 years. Data analysis included descriptive statistics and general linear regression models. RESULTS Depression was the most common mental illness, and there were no gender differences in prevalence. Both men and women believed that they knew some of the symptoms and causal factors of mental illness. Their attitudes suggested they are not very open to acknowledging psychological problems, are very concerned about stigma associated with mental illness, and are somewhat open to seeking mental health services, but they prefer religious coping. Significant gender and age differences were evident in attitudes and preferred coping. DISCUSSION Our findings have implications for gender- and age-specific psychoeducation interventions and future research. For instance, psychoeducation or community awareness programs designed to increase openness to psychological problems and reduce stigma are needed. Also, exploration of partnerships between faith-based organizations and mental health services could be helpful to African Americans.
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Lang TE, Brown RL, St. Lawrence WF, Bradley CC. Buckling characteristics of a sloping snow slab. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/jb078i002p00339] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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An FP, Bai JZ, Balantekin AB, Band HR, Beavis D, Beriguete W, Bishai M, Blyth S, Boddy K, Brown RL, Cai B, Cao GF, Cao J, Carr R, Chan WT, Chang JF, Chang Y, Chasman C, Chen HS, Chen HY, Chen SJ, Chen SM, Chen XC, Chen XH, Chen XS, Chen Y, Chen YX, Cherwinka JJ, Chu MC, Cummings JP, Deng ZY, Ding YY, Diwan MV, Dong L, Draeger E, Du XF, Dwyer DA, Edwards WR, Ely SR, Fang SD, Fu JY, Fu ZW, Ge LQ, Ghazikhanian V, Gill RL, Goett J, Gonchar M, Gong GH, Gong H, Gornushkin YA, Greenler LS, Gu WQ, Guan MY, Guo XH, Hackenburg RW, Hahn RL, Hans S, He M, He Q, He WS, Heeger KM, Heng YK, Hinrichs P, Ho TH, Hor YK, Hsiung YB, Hu BZ, Hu T, Hu T, Huang HX, Huang HZ, Huang PW, Huang X, Huang XT, Huber P, Isvan Z, Jaffe DE, Jetter S, Ji XL, Ji XP, Jiang HJ, Jiang WQ, Jiao JB, Johnson RA, Kang L, Kettell SH, Kramer M, Kwan KK, Kwok MW, Kwok T, Lai CY, Lai WC, Lai WH, Lau K, Lebanowski L, Lee J, Lee MKP, Leitner R, Leung JKC, Leung KY, Lewis CA, Li B, Li F, Li GS, Li J, Li QJ, Li SF, Li WD, Li XB, Li XN, Li XQ, Li Y, Li ZB, Liang H, Liang J, Lin CJ, Lin GL, Lin SK, Lin SX, Lin YC, Ling JJ, Link JM, Littenberg L, Littlejohn BR, Liu BJ, Liu C, Liu DW, Liu H, Liu JC, Liu JL, Liu S, Liu X, Liu YB, Lu C, Lu HQ, Luk A, Luk KB, Luo T, Luo XL, Ma LH, Ma QM, Ma XB, Ma XY, Ma YQ, Mayes B, McDonald KT, McFarlane MC, McKeown RD, Meng Y, Mohapatra D, Morgan JE, Nakajima Y, Napolitano J, Naumov D, Nemchenok I, Newsom C, Ngai HY, Ngai WK, Nie YB, Ning Z, Ochoa-Ricoux JP, Oh D, Olshevski A, Pagac A, Patton S, Pearson C, Pec V, Peng JC, Piilonen LE, Pinsky L, Pun CSJ, Qi FZ, Qi M, Qian X, Raper N, Rosero R, Roskovec B, Ruan XC, Seilhan B, Shao BB, Shih K, Steiner H, Stoler P, Sun GX, Sun JL, Tam YH, Tanaka HK, Tang X, Themann H, Torun Y, Trentalange S, Tsai O, Tsang KV, Tsang RHM, Tull C, Viren B, Virostek S, Vorobel V, Wang CH, Wang LS, Wang LY, Wang LZ, Wang M, Wang NY, Wang RG, Wang T, Wang W, Wang X, Wang X, Wang YF, Wang Z, Wang Z, Wang ZM, Webber DM, Wei YD, Wen LJ, Wenman DL, Whisnant K, White CG, Whitehead L, Whitten CA, Wilhelmi J, Wise T, Wong HC, Wong HLH, Wong J, Worcester ET, Wu FF, Wu Q, Xia DM, Xiang ST, Xiao Q, Xing ZZ, Xu G, Xu J, Xu J, Xu JL, Xu W, Xu Y, Xue T, Yang CG, Yang L, Ye M, Yeh M, Yeh YS, Yip K, Young BL, Yu ZY, Zhan L, Zhang C, Zhang FH, Zhang JW, Zhang QM, Zhang K, Zhang QX, Zhang SH, Zhang YC, Zhang YH, Zhang YX, Zhang ZJ, Zhang ZP, Zhang ZY, Zhao J, Zhao QW, Zhao YB, Zheng L, Zhong WL, Zhou L, Zhou ZY, Zhuang HL, Zou JH. Observation of electron-antineutrino disappearance at Daya Bay. PHYSICAL REVIEW LETTERS 2012; 108:171803. [PMID: 22680853 DOI: 10.1103/physrevlett.108.171803] [Citation(s) in RCA: 124] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Indexed: 05/23/2023]
Abstract
The Daya Bay Reactor Neutrino Experiment has measured a nonzero value for the neutrino mixing angle θ(13) with a significance of 5.2 standard deviations. Antineutrinos from six 2.9 GWth reactors were detected in six antineutrino detectors deployed in two near (flux-weighted baseline 470 m and 576 m) and one far (1648 m) underground experimental halls. With a 43,000 ton-GWth-day live-time exposure in 55 days, 10,416 (80,376) electron-antineutrino candidates were detected at the far hall (near halls). The ratio of the observed to expected number of antineutrinos at the far hall is R=0.940±0.011(stat.)±0.004(syst.). A rate-only analysis finds sin(2)2θ(13)=0.092±0.016(stat.)±0.005(syst.) in a three-neutrino framework.
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Semeniuk Y, Brown RL, Riesch SK, Zywicki M, Hopper J, Henriques JB. The Strengthening Families Program 10-14: influence on parent and youth problem-solving skill. J Psychiatr Ment Health Nurs 2010; 17:392-402. [PMID: 20584236 PMCID: PMC3058939 DOI: 10.1111/j.1365-2850.2009.01534.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The aim of this paper is to report the results of a preliminary examination of the efficacy of the Strengthening Families Program (SFP) 10-14 in improving parent and youth problem-solving skill. The Hypotheses in this paper include: (1) youth and parents who participated in SFP would have lower mean scores immediately (T2) and 6 months (T3) post intervention on indicators of hostile and negative problem-solving strategies; (2) higher mean scores on positive problem-solving strategies; and (3) youth who participated in SFP would have higher mean scores at T2 and at T3 on indicators of individual problem solving and problem-solving efficacy than youth in the comparison group. The dyads were recruited from elementary schools that had been stratified for race and assigned randomly to intervention or comparison conditions. Mean age of youth was 11 years (SD = 1.04). Fifty-seven dyads (34-intervention&23-control) were videotaped discussing a frequently occurring problem. The videotapes were analysed using the Iowa Family Interaction Rating Scale (IFIRS) and data were analysed using Dyadic Assessment Intervention Model. Most mean scores on the IFIRS did not change. One score changed as predicted: youth hostility decreased at T3. Two scores changed contrary to prediction: parent hostility increased T3 and parent positive problem solving decreased at T2. SFP demonstrated questionable efficacy for problem-solving skill in this study.
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Baker RL, Brown RL, Chen ZY, Cleveland TE, Fakhoury AM. A maize trypsin inhibitor (ZmTIp) with limited activity against Aspergillus flavus. J Food Prot 2009; 72:185-8. [PMID: 19205484 DOI: 10.4315/0362-028x-72.1.185] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Infection of maize both pre- and postharvest by Aspergillus flavus is a severe agricultural problem in the southern United States. Aflatoxins are secondary metabolites produced by A. flavus and are carcinogenic to humans and animals upon ingestion. Extensive research has been conducted to identify sources of resistance to A. flavus in maize. Some maize genotypes exhibit greater resistance to A. flavus than others. Many research groups have validated the role of plant trypsin inhibitors (TIs) as a means of plant defense against fungal infection. Research consisting of the cloning, expression, and partial characterization of one previously uncharacterized TI protein has been conducted. The overexpressed protein displayed TI activity, as expected, and some ability to alter germination of conidia (8%) from several fungal pathogens and to inhibit hyphal growth (30%). This effect on fungal growth, although less than that of previously investigated TIs, marks this protein as a potential source of resistance to aflatoxin accumulation in maize.
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Chen ZY, Brown RL, Guo BZ, Menkir A, Cleveland TE. Identifying Aflatoxin Resistance-related Proteins/Genes through Proteomics and RNAi Gene Silencing1. ACTA ACUST UNITED AC 2009. [DOI: 10.3146/at07-005.1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Abstract
Aflatoxins are carcinogenic secondary metabolites produced mainly by Aspergillus flavus Link ex. Fries, and A. prarasiticus Speare during infection of susceptible crops, such as maize, cottonseed, peanuts and tree nuts. This paper will review research efforts in identifying aflatoxin resistance-related proteins/genes in maize. Similar strategies may be useful in peanut. For maize, although genotypes resistant to A. flavus infection or aflatoxin production have been identified, the incorporation of resistance into commercial lines has been slow due to the lack of selectable markers and poor understanding of host resistance mechanisms. Recently, resistance-associated proteins (RAPs) were identified through proteomic comparison of constitutive protein profiles between resistant and susceptible maize genotypes. These proteins belong to three major groups based on their peptide sequence homologies: storage proteins, stress-related proteins, and antifungal proteins. Preliminary characterization of some of these RAPs suggest that they play a direct role in host resistance, such as pathogenesis-related protein 10 (PR10), or an indirect role, such as glyoxalase I (GLX I), through enhancing the host stress tolerance. To verify whether these RAPs play a role in host resistance, RNA interference (RNAi) gene silencing technique was used to silence the expression of these genes in maize. RNAi vectors (glx I RNAi and pr10 RNAi) were constructed using Gateway technology, and then transformed into immature maize embryos using both bombardment and Agrobacterium infection. The extent of gene silencing in transgenic callus tissues ranged from 20% to over 99%. The RNAi silenced transgenic maize seeds have also been obtained from plants regenerated from Agrobacterium transformed callus lines. Kernel screen assay of the transgenic maize kernels demonstrated a significant increase in susceptibility to A. flavus colonization and aflatoxin production in some of the silenced transgenic lines compared with non-silenced control kernels, suggesting the direct involvement of these two proteins in aflatoxin resistance in maize.
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Baker RL, Brown RL, Chen ZY, Cleveland TE, Fakhoury AM. A maize lectin-like protein with antifungal activity against Aspergillus flavus. J Food Prot 2009; 72:120-7. [PMID: 19205472 DOI: 10.4315/0362-028x-72.1.120] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The filamentous fungus Aspergillus flavus causes an ear rot on maize and produces a mycotoxin (aflatoxin) in colonized maize kernels. Aflatoxins are carcinogenic to humans and animals upon ingestion. Aflatoxin contamination results in a large loss of profits and marketable yields for farmers each year. Several research groups have worked to pinpoint sources of resistance to A. flavus and the resulting aflatoxin contamination in maize. Some maize genotypes exhibit greater resistance than others. A proteomics approach has recently been used to identify endogenous maize proteins that may be associated with resistance to the fungus. Research has been conducted on cloning, expression, and partial characterization of one such protein, which has a sequence similar to that of cold-regulated proteins. The expressed protein, ZmCORp, exhibited lectin-like hemagglutination activity against fungal conidia and sheep erythrocytes. Quantitative real-time PCR assays revealed that ZmCOR is expressed 50% more in maize kernels from the Mp420 line, a type of maize resistant to A. flavus, compared with the expression level of the gene in the susceptible B73 line. ZmCORp exhibited fungistatic activity when conidia from A. flavus were exposed to the protein at a final concentration of 18 mM. ZmCORp inhibited the germination of conidia by 80%. A 50% decrease in mycelial growth resulted when germinated conidia were incubated with the protein. The partial characterization of ZmCORp suggests that this protein may play an important role in enhancing kernel resistance to A. flavus infection and aflatoxin accumulation.
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Chen ZY, Brown RL, Damann KE, Cleveland TE. Identification of Maize Kernel Endosperm Proteins Associated with Resistance to Aflatoxin Contamination by Aspergillus flavus. PHYTOPATHOLOGY 2007; 97:1094-103. [PMID: 18944174 DOI: 10.1094/phyto-97-9-1094] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
ABSTRACT Aflatoxins are carcinogens produced mainly by Aspergillus flavus during infection of susceptible crops such as maize (Zea mays). Previously, embryo proteins from maize genotypes resistant or susceptible to A. flavus infection were compared using proteomics, and resistance-associated proteins were identified. Here, we report the comparison of maize endosperm proteins from five resistant and five susceptible genotypes, and the identification of additional resistance-associated proteins using the same approach. Ten protein spots were upregulated twofold or higher in resistant lines compared with susceptible ones. Peptide sequencing of these proteins identified them as a globulin-2 protein, late embryogenesis abundant proteins (LEA3 and LEA14), a stress-related peroxiredoxin antioxidant (PER1), heat-shock proteins (HSP17.2), a cold-regulated protein (COR), and an antifungal trypsin-inhibitor protein (TI). The gene encoding one such upregulated protein, PER1, was cloned and overexpressed in Escherichia coli. The overexpressed PER1 protein demonstrated peroxidase activity in vitro. In addition, per1 expression was significantly higher in the resistant genotype Mp420 than in the susceptible genotype B73 during the late stage of kernel development, and was significantly induced upon A. flavus infection, suggesting that it may play an important role in enhancing kernel stress tolerance and aflatoxin resistance. The significance of other identified proteins to host resistance and stress tolerance also is discussed.
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Babushok VI, Linstrom PJ, Reed JJ, Zenkevich IG, Brown RL, Mallard WG, Stein SE. Development of a database of gas chromatographic retention properties of organic compounds. J Chromatogr A 2007; 1157:414-21. [PMID: 17543315 DOI: 10.1016/j.chroma.2007.05.044] [Citation(s) in RCA: 132] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2007] [Revised: 05/01/2007] [Accepted: 05/03/2007] [Indexed: 11/21/2022]
Abstract
A comprehensive database of gas chromatographic retention properties of chemical compounds has been developed using multiple literature sources. The National Institute of Standards and Technology (NIST) database of retention data for non-polar and polar stationary phases currently contains 292,924 data records for 42,888 compounds. The database includes data for Kováts indices, linear indices, Lee indices, retention times and retention volumes. The first release of this database for non-polar stationary phases is available with NIST/US Environmental Protection Agency (EPA)/National Institutes of Health (NIH) Mass Spectral Database (June 2005) and through the internet (NIST Chemistry WebBook). The paper describes the database and the process by which it has been compiled. The format of data presentation and the quality control procedures are described. Data sources of gas chromatographic retention data are also discussed.
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Brown RL, Greenhalgh DG. Mouse models to study wound closure and topical treatment of infected wounds in healing-impaired and normal healing hosts. Wound Repair Regen 2007; 5:198-204. [PMID: 16984431 DOI: 10.1046/j.1524-475x.1997.50213.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Full-thickness wounds were made on the backs of wound healing-impaired diabetic mice and their normally healing litter mates. The wounds were then inoculated with 10(4) colony-forming units of Pseudomonas aeruginosa. In both cases, the inoculum increased rapidly to between 10(9) and 10(10) colony-forming units/wound area. The infection caused a significant decrease in wound closure in the normally healing mice. In the wound healing-impaired diabetic mice, infection increased the size of the wound area over 100% by day 21. The wound became filled with inflammatory cells and serous fluid, and the mice lost significant amounts of weight, an additional sign of severe, ongoing infection. Early antimicrobial treatment of infected wounds in diabetic mice (1 hour after wounding and microbial inoculation) reversed the increase in wound size area, improved wound closure, and reduced to a significant degree the weight loss observed in untreated control mice. Delay in treatment for as little as 8 hours significantly reduces the efficacy of antimicrobial treatment. These models can be used to study the effects of infection as well as to determine the efficacy of topical antimicrobial and/or wound healing-enhancing substances on these wounds in both normally healing and healing-impaired hosts.
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Brown RL, Chen Z, Menkir A, Cleveland TE. Proteomics to identify resistance factors in corn-a review. Mycotoxin Res 2006; 22:22-6. [DOI: 10.1007/bf02954553] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Chen ZY, Brown RL, Rajasekaran K, Damann KE, Cleveland TE. Identification of a Maize Kernel Pathogenesis-Related Protein and Evidence for Its Involvement in Resistance to Aspergillus flavus Infection and Aflatoxin Production. PHYTOPATHOLOGY 2006; 96:87-95. [PMID: 18944208 DOI: 10.1094/phyto-96-0087] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
ABSTRACT Aflatoxins are carcinogens produced by Aspergillus flavus and A. parasiticus during infection of susceptible crops such as maize. Several aflatoxin-resistant maize genotypes have been identified and kernel proteins have been suggested to play an important role in resistance. In the present study, one protein (#717), which was expressed fivefold higher in three resistant lines compared with three susceptible ones, was identified using proteomics. This protein was sequenced and identified as a pathogenesis-related protein (PR-10) based on its sequence homology. To assess the involvement of this PR-10 protein (ZmPR-10) in host resistance of maize against fungal infection and aflatoxin production, the corresponding cDNA (pr-10) was cloned. It encodes a protein of 160 amino acids with a predicted molecular mass of 16.9 kDa and an iso-electric point of 5.38. The expression of pr-10 during kernel development increased fivefold between 7 and 22 days after pollination, and was induced upon A. flavus infection in the resistant but not in the susceptible genotype. The ZmPR-10 overexpressed in Escherichia coli exhibited a ribonucleolytic and antifungal activities. Leaf extracts of transgenic tobacco plants expressing maize pr-10 also demonstrated RNase activity and inhibited the growth of A. flavus. This evidence suggests that ZmPR-10 plays a role in kernel resistance by inhibiting fungal growth of A. flavus.
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Chen ZY, Brown RL, Damann KE, Cleveland TE. Identification of a Maize Kernel Stress-Related Protein and Its Effect on Aflatoxin Accumulation. PHYTOPATHOLOGY® 2004; 94:938-45. [PMID: 0 DOI: 10.1094/phyto.2004.94.9.938] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Aflatoxins are carcinogens produced mainly by Aspergillus flavus during infection of susceptible crops such as maize. Through proteomic comparisons of maize kernel embryo proteins of resistant and susceptible genotypes, several protein spots previously were found to be unique or upregulated in resistant embryos. In the present study, one of these protein spots was sequenced and identified as glyoxalase I (GLX-I; EC 4.4.1.5). The full-length cDNA of the glyoxalase I gene (glx-I) was cloned. GLX-I constitutive activity was found to be significantly higher in the resistant maize lines compared with susceptible ones. After kernel infection by A. flavus, GLX-I activity remained lower in susceptible genotypes than in resistant genotypes. However, fungal infection significantly increased methylglyoxal (MG) levels in two of three susceptible genotypes. Further, MG was found to induce aflatoxin production in A. flavus culture at a concentration as low as 5.0 μM. The mode of action of MG may be to stimulate the expression of aflR, an aflatoxin biosynthesis regulatory gene, which was found to be significantly upregulated in the presence of 5 to 20 μM MG. These data suggest that GLX-I may play an important role in controlling MG levels inside kernels, thereby contributing to the lower levels of aflatoxins found in resistant maize genotypes.
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Chen ZY, Brown RL, Damann KE, Cleveland TE. Identification of unique or elevated levels of kernel proteins in aflatoxin-resistant maize genotypes through proteome analysis. PHYTOPATHOLOGY 2002; 92:1084-94. [PMID: 18944219 DOI: 10.1094/phyto.2002.92.10.1084] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
ABSTRACT Aflatoxins are carcinogens produced by Aspergillus flavus and A. parasiticus during infection of susceptible crops such as maize (Zea mays L.). Resistant maize genotypes have been identified, but the incorporation of resistance into commercial lines has been slow due to the lack of selectable markers. Here we report the identification of potential markers in resistant maize lines using a proteomics approach. Kernel embryo proteins from each of two resistant genotypes have been compared with those from a composite of five susceptible genotypes using large format two-dimensional gel electrophoresis. Through these comparisons, both quantitative and qualitative differences have been identified. Protein spots have been sequenced, and based on peptide sequence homology analysis, are categorized as follows: storage proteins (globulin 1 and globulin 2), late embryogenesis abundant (LEA) proteins related to drought or desiccation (LEA3 and LEA14), water- or osmo-stress related proteins (WSI18 and aldose reductase), and heat-stress related proteins (HSP16.9). Aldose reductase activity measured in resistant and susceptible genotypes before and after infection suggests the importance of constitutive levels of this enzyme to resistance. Results of this study point to a correlation between host resistance and stress tolerance. The putative function of each identified protein is discussed.
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Bugosh J, Brown RL, McWhorter JR, Sears GW, Sippel RJ. A Novel Fine Alumina Powder, Fibrillar Boehmite. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/i360003a004] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Stein SE, Brown RL. Estimation of normal boiling points from group contributions. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/ci00019a016] [Citation(s) in RCA: 214] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Stein SE, Brown RL. .pi.-Electron properties of large condensed polyaromatic hydrocarbons. J Am Chem Soc 2002. [DOI: 10.1021/ja00246a033] [Citation(s) in RCA: 229] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Stein SE, Brown RL. Prediction of carbon-hydrogen bond dissociation energies for polycyclic aromatic hydrocarbons of arbitrary size. J Am Chem Soc 2002. [DOI: 10.1021/ja00003a009] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Fantes JA, Mewborn SK, Lese CM, Hedrick J, Brown RL, Dyomin V, Chaganti RSK, Christian SL, Ledbetter DH. Organisation of the pericentromeric region of chromosome 15: at least four partial gene copies are amplified in patients with a proximal duplication of 15q. J Med Genet 2002; 39:170-7. [PMID: 11897815 PMCID: PMC1735052 DOI: 10.1136/jmg.39.3.170] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Clinical cytogenetic laboratories frequently identify an apparent duplication of proximal 15q that does not involve probes within the PWS/AS critical region and is not associated with any consistent phenotype. Previous mapping data placed several pseudogenes, NF1, IgH D/V, and GABRA5 in the pericentromeric region of proximal 15q. Recent studies have shown that these pseudogene sequences have increased copy numbers in subjects with apparent duplications of proximal 15q. To determine the extent of variation in a control population, we analysed NF1 and IgH D pseudogene copy number in interphase nuclei from 20 cytogenetically normal subjects by FISH. Both loci are polymorphic in controls, ranging from 1-4 signals for NF1 and 1-3 signals for IgH D. Eight subjects with apparent duplications, examined by the same method, showed significantly increased NF1 copy number (5-10 signals). IgH D copy number was also increased in 6/8 of these patients (4-9 signals). We identified a fourth pseudogene, BCL8A, which maps to the pericentromeric region and is coamplified along with the NF1 sequences. Interphase FISH ordering experiments show that IgH D lies closest to the centromere, while BCL8A is the most distal locus in this pseudogene array; the total size of the amplicon is estimated at approximately 1 Mb. The duplicated chromosome was inherited from either sex parent, indicating no parent of origin effect, and no consistent phenotype was present. FISH analysis with one or more of these probes is therefore useful in discriminating polymorphic amplification of proximal pseudogene sequences from clinically significant duplications of 15q.
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