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Ruibal MP, Peakall R, Smith LM, Linde CC. Phylogenetic and microsatellite markers for Tulasnella (Tulasnellaceae) mycorrhizal fungi associated with Australian orchids. APPLICATIONS IN PLANT SCIENCES 2013; 1:apps1200394. [PMID: 25202528 PMCID: PMC4105285 DOI: 10.3732/apps.1200394] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Accepted: 09/09/2012] [Indexed: 06/02/2023]
Abstract
PREMISE OF THE STUDY Phylogenetic and microsatellite markers were developed for Tulasnella mycorrhizal fungi to investigate fungal species identity and diversity. These markers will be useful in future studies investigating the phylogenetic relationship of the fungal symbionts, specificity of orchid-mycorrhizal associations, and the role of mycorrhizae in orchid speciation within several orchid genera. • METHODS AND RESULTS We generated partial genome sequences of two Tulasnella symbionts originating from Chiloglottis and Drakaea orchid species with 454 genome sequencing. Cross-genus transferability across mycorrhizal symbionts associated with multiple genera of Australian orchids (Arthrochilus, Chiloglottis, Drakaea, and Paracaleana) was found for seven phylogenetic loci. Five loci showed cross-transferability to Tulasnella from other orchid genera, and two to Sebacina. Furthermore, 11 polymorphic microsatellite loci were developed for Tulasnella from Chiloglottis. • CONCLUSIONS Highly informative markers were obtained, allowing investigation of mycorrhizal diversity of Tulasnellaceae associated with a wide variety of terrestrial orchids in Australia and potentially worldwide.
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Smith LM, McWhorter AR, Shellam GR, Redwood AJ. The genome of murine cytomegalovirus is shaped by purifying selection and extensive recombination. Virology 2012; 435:258-68. [PMID: 23107009 DOI: 10.1016/j.virol.2012.08.041] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Revised: 08/02/2012] [Accepted: 08/24/2012] [Indexed: 11/19/2022]
Abstract
The herpesvirus lifestyle results in a long-term interaction between host and invading pathogen, resulting in exquisite adaptation of virus to host. We have sequenced the genomes of nine strains of murine cytomegalovirus (a betaherpesvirus), isolated from free-living mice trapped at locations separated geographically and temporally. Despite this separation these genomes were found to have low levels of nucleotide variation. Of the more than 160 open reading frames, almost 90% had a dN/dS ratio of amino acid substitutions of less than 0.6, indicating the level of purifying selection on the coding potential of MCMV. Examination of selection acting on individual genes at the codon level however indicates some level of positive selection, with 0.03% of codons showing strong evidence for positive selection. Conversely, 1.3% of codons show strong evidence of purifying selection. Alignments of both genome sequences and coding regions suggested that high levels of recombination have shaped the MCMV genome.
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Tang W, Zhu L, Smith LM. Controlling DNA Fragmentation in MALDI-MS by Chemical Modification. Anal Chem 2012; 69:302-12. [PMID: 21639184 DOI: 10.1021/ac960865o] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Fragmentation has proven to be a major factor limiting accessible mass range, sensitivity, and mass resolution in the analysis of DNA by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). Previous work has shown that this DNA fragmentation is strongly dependent on both the MALDI matrix and the nucleic acid sequence employed. Fragmentation is initiated by nucleobase protonation, leading to cleavage of the N-glycosidic bond with base loss, followed by cleavage of the phosphodiester backbone. In this study, asymmetric oligonucleotides incorporating cytidine and cytidine analogs such as 5-methyl-2'-deoxycytidine, 5-bromo-2'-deoxycytidine, aracytidine, and 2'-fluorodeoxycytidine nucleosides were used to systematically investigate the influence of the structural changes on the stability of the N-glycosidic bond. Modifications of the deoxyribose sugar ring by replacing the 2'-hydrogen with more electron-withdrawing groups such as the hydroxyl or fluoro group stabilize the N-glycosidic bond to a greater extent than the C5 nucleobase modifications. 2'-Hydroxyl and 2'-fluoro groups respectively are shown to partially or completely block fragmentation at the modified nucleosides. Mixtures of oligonucleotides incorporating such modifications demonstrate remarkably extended accessible mass range, as well as increased sensitivity and mass resolution. The stabilization provided by these chemical modifications also expands the range of matrices useful for nucleic acid analysis, yielding in some cases greatly improved performance.
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Summers JK, Smith LM, Case JL, Linthurst RA. A review of the elements of human well-being with an emphasis on the contribution of ecosystem services. AMBIO 2012; 41:327-40. [PMID: 22581385 PMCID: PMC3393065 DOI: 10.1007/s13280-012-0256-7] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Revised: 09/16/2011] [Accepted: 01/31/2012] [Indexed: 05/06/2023]
Abstract
Natural ecosystems perform fundamental life-support services upon which human civilization depends. However, many people believe that nature provides these services for free and therefore, they are of little or no value. While we do not pay for them, we pay significantly for their loss in terms of wastewater treatment facilities, moratoriums on greenhouse gases, increased illnesses, reduced soil fertility and losses in those images of nature that contribute to our basic happiness. Little is understood about the well-being benefits of the natural environment and its ecosystem services. The interwoven relationship of ecosystems and human well-being is insufficiently acknowledged in the wider philosophical, social, and economic well-being literature. In this article, we discuss an approach to examine human well-being and the interactions of its four primary elements-basic human needs, economic needs, environmental needs, and subjective well-being-and ecosystem services.
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Geitner NK, Doepke A, Fickenscher MA, Yarrison-Rice JM, Heineman WR, Jackson HE, Smith LM. The morphology and evolution of bipyramidal gold nanoparticles. NANOTECHNOLOGY 2011; 22:275607. [PMID: 21597144 DOI: 10.1088/0957-4484/22/27/275607] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We examine the growth and evolution with time of bipyramidal gold nanoparticles grown by a seed-mediated process. The nanoparticles are characterized both by their physical dimensions determined by transmission electron microscopy and by the wavelength position of their localized surface plasmon resonance. Each growth's physical dimensions correspond to particular initial conditions, and we observe two distinct modes of temporal evolution during growth. The effects of varying silver nitrate concentration and growth time are also explored. We observe a linear relationship between the tip radius of curvature and the wavelength of the longitudinal localized surface plasmon resonance (LSPR) peak. Critical parameters for synthesizing bipyramidal nanoparticles with sharp tips and correct length to width ratio are determined.
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Rachagani S, Senapati S, Chakraborty S, Ponnusamy MP, Kumar S, Smith LM, Jain M, Batra SK. Activated KrasG¹²D is associated with invasion and metastasis of pancreatic cancer cells through inhibition of E-cadherin. Br J Cancer 2011; 104:1038-48. [PMID: 21364589 PMCID: PMC3065271 DOI: 10.1038/bjc.2011.31] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Background: Pancreatic cancer (PC) harbours an activated point mutation (KrasG12D) in the Kras proto-oncogene that has been demonstrated to promote the development of PC. Methods: This study was designed to investigate the effect of the oncogenic KrasG12D allele on aggressiveness and metastatic potential of PC cells. We silenced the oncogenic KrasG12D allele expression in CD18/HPAF and ASPC1 cell lines by stable expression of shRNA specific to the KrasG12Dallele. Results: The KrasG12D knockdown cells exhibited a significant decrease in motility (P<0.0001), invasion (P<0.0001), anchorage-dependent (P<0.0001) and anchorage-independent growth (P<0.0001), proliferation (P<0.005) and an increase in cell doubling time (P<0.005) in vitro and a decrease in the incidence of metastases upon orthotopic implantation into nude mice. The knockdown of the KrasG12D allele led to a significant increase in the expression of E-cadherin (mRNA and protein) both in vitro and in vivo. This was associated with a decrease in the expression of phoshpo-ERK-1/2, NF-κB and MMP-9, and transcription factors such as δEF1, Snail and ETV4. Furthermore, the expression of several proteins involved in cell survival, invasion and metastasis was decreased in the KrasG12D knockdown cells. Conclusions: The results of this study suggest that the KrasG12D allele promotes metastasis in PC cells partly through the downregulation of E-cadherin.
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Gardner K, Bird J, Canning PM, Frizzell LM, Smith LM. Prevalence of overweight, obesity and underweight among 5-year-old children in Saint Lucia by three methods of classification and a comparison with historical rates. Child Care Health Dev 2011; 37:143-9. [PMID: 20854448 DOI: 10.1111/j.1365-2214.2010.01154.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
BACKGROUND The study aimed to determine if child obesity rates have risen in the Caribbean nation of Saint Lucia, as found globally, and whether under-nutrition coexists, as in other developing nations. The average adult in Saint Lucia is overweight, thus considerable child obesity might be expected, but there are no current data. METHODS Heights and weights were obtained from a sample (n= 425) of the 2001 birth cohort of Saint Lucian children measured during the nation-wide 2006/2007 Prior to School Entry Five-Year Assessment. Prevalence of overweight, obesity and underweight were estimated by Centers for Disease Control (CDC), Cole et al. and new World Health Organization (WHO) methods. Previously reported 1976 estimates, including children ≤60 months of age only, based on National Centre for Health Statistics curves, were adjusted to new WHO equivalents using an algorithm developed by Yang and de Onis, and compared with rates in our subsample of children ≤60 months of age (n= 99). RESULTS Regardless of classification method, overweight and obesity rates were high: 14.4% and 9.2% (WHO); 11.3% and 12.0% (CDC); and 9.9% and 7.1% (Cole et al.), respectively. Underweight estimates also varied: 4.7% (WHO); 11.3% (CDC) and 6.6% (Cole et al.). Obesity in our young subsample (15.2%; WHO) was more than 3 times the adjusted 1976 rate (4.3%). CONCLUSIONS Obesity among Saint Lucian pre-schoolers has tripled in 30 years. Our findings also suggest that this country, like many undergoing a 'nutrition transition', faces the dual challenge of over-nutrition and under-nutrition. Routine monitoring of overweight and underweight is needed in Saint Lucia, as is the implementation and evaluation of programmes to address these problems.
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Roche SA, Carter RJ, Peakall R, Smith LM, Whitehead MR, Linde CC. A narrow group of monophyletic Tulasnella (Tulasnellaceae) symbiont lineages are associated with multiple species of Chiloglottis (Orchidaceae): Implications for orchid diversity. AMERICAN JOURNAL OF BOTANY 2010; 97:1313-27. [PMID: 21616884 DOI: 10.3732/ajb.1000049] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
PREMISE OF THE STUDY The Orchidaceae is characterized by exceptional species diversity. Obligate orchid mycorrhizae are predicted to determine orchid distributions, and highly specific relationships between orchids and fungi may drive orchid diversification. In this study, mycorrhizal diversity was examined in the terrestrial, photosynthetic orchid genus Chiloglottis to test the hypothesis of mycorrhizal-mediated diversification in the genus Chiloglottis. This orchid genus secures pollination by sexual deception, an obligate and highly specific pollination strategy. Here we asked whether the obligate orchid-fungal interactions are also specific. • METHODS Two sequenced loci, the internal transcribed spacer region (ITS) and mitochondrial large subunit (mtLSU), were used to identify fungal isolates and assess fungal species diversity. Symbiotic germination of two species Chiloglottis aff. jeanesii and C. valida were used to assess germination potential of isolates and confirm mycorrhizal association. • KEY RESULTS Phylogenetic analyses revealed that six representative Chiloglottis species spanning a broad survey of the genus were all associated with a narrow group of monophyletic Tulasnella fungal lineages. • CONCLUSIONS The Chiloglottis-Tulasnella interaction appears to be the first known case of such a narrow symbiont association across a broadly surveyed orchid genus. It appears that the specific pollination system of Chiloglottis, rather than specific orchid-fungal interactions has been the key driving force in the diversification of the genus. These findings also indicate that plant groups with highly specific mycorrhizal partners can have a widespread distribution.
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Sai AJ, Gallagher JC, Smith LM, Logsdon S. Fall predictors in the community dwelling elderly: a cross sectional and prospective cohort study. JOURNAL OF MUSCULOSKELETAL & NEURONAL INTERACTIONS 2010; 10:142-150. [PMID: 20516631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
OBJECTIVES To ascertain the risk factors for falls, stumbles and recurrent falls in a cohort of elderly people with mean age of 76.7-/+6.1 years. METHODS 137 community dwelling elderly living independently or in assisted living institutions participated in the study. Each subject was assessed by history, physical examination and physical performance tests at the beginning and end of study. Falls and stumbles were recorded in a falls dairy for 1 year. RESULTS Significant predictors of being a faller were a history of falls at baseline (Odds Ratio (OR) = 3.85, 95% Confidence Interval (CI) = 1.56 - 9.50), depression (OR = 1.19, 95% CI = 1.02 - 1.38) and timed rise (Incident Rate Ratio (IRR) = 1.24, 95% CI = 1.03 - 1.50). For predicting recurrent fallers Receiver Operator Characteristic (ROC) curves were as follows: 0.71 (95%CI 0.61-0.81) for timed up and go, 0.67 (95%CI 0.56-0.78) for timed rise and 0.70 (95%CI 0.60-0.80) for timed walk fast pace. CONCLUSIONS Timed rise was the single most important test that was able to predict both a first time faller and recurrent faller. Timed up and go was the most significant test to predict recurrent fallers.
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Kang JH, Gao Q, Joyce HJ, Tan HH, Jagadish C, Kim Y, Choi DY, Guo Y, Xu H, Zou J, Fickenscher MA, Smith LM, Jackson HE, Yarrison-Rice JM. Novel growth and properties of GaAs nanowires on Si substrates. NANOTECHNOLOGY 2010; 21:035604. [PMID: 19966397 DOI: 10.1088/0957-4484/21/3/035604] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Straight, vertically aligned GaAs nanowires were grown on Si(111) substrates coated with thin GaAs buffer layers. We find that the V/III precursor ratio and growth temperature are crucial factors influencing the morphology and quality of buffer layers. A double layer structure, consisting of a thin initial layer grown at low V/III ratio and low temperature followed by a layer grown at high V/III ratio and high temperature, is crucial for achieving straight, vertically aligned GaAs nanowires on Si(111) substrates. An in situ annealing step at high temperature after buffer layer growth improves the surface and structural properties of the buffer layer, which further improves the morphology of the GaAs nanowire growth. Through such optimizations we show that vertically aligned GaAs nanowires can be fabricated on Si(111) substrates and achieve the same structural and optical properties as GaAs nanowires grown directly on GaAs(111)B substrates.
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Chang L, Cloak C, Jiang CS, Farnham S, Tokeshi B, Buchthal S, Hedemark B, Smith LM, Ernst T. Altered neurometabolites and motor integration in children exposed to methamphetamine in utero. Neuroimage 2009; 48:391-7. [PMID: 19576287 DOI: 10.1016/j.neuroimage.2009.06.062] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2009] [Revised: 06/17/2009] [Accepted: 06/18/2009] [Indexed: 11/16/2022] Open
Abstract
Methamphetamine (METH) is a neurotoxic drug. This study aimed to evaluate brain metabolite levels and cognitive function in young children with prenatal METH exposure. 101 children ages 3-4 years were evaluated with neuropsychological tests and underwent proton magnetic resonance spectroscopy ((1)H-MRS) without sedation. Complete datasets from 49 METH-exposed and 49 controls who completed the neuropsychological test battery, and 38 METH-exposed and 37 controls with high-quality MR spectra are reported here. Despite similar physical characteristics (including head circumference), global cognitive function (on Stanford-Binet), parental education, intelligence, mood, and socioeconomic status, METH-exposed children had higher total creatine (tCr: +7%, p=0.003), N-acetyl compounds (NA: +4.3%, p=0.004) and glutamate+glutamine (GLX: +9.6%, p=0.02) concentrations in the frontal white matter, but lower myoinositol (MI: -7%, p=0.01) and MI/tCr (-7.5%, p=0.03) in the thalamus, than control children. The higher frontal white matter NA in the METH-exposed children was due to the higher NA in the METH-exposed girls (+10.2%, p=0.003), but not the boys (+0.8%) compared to sex-matched controls. Furthermore, the METH-exposed children had poorer performance on a visual motor integration (VMI) task, which correlated with lower MI in the thalamus (r=0.26, p=0.03). The higher NA, tCr and GLX concentrations suggest higher neuronal density or cellular compactness in the white matter, especially in the girls, whereas the lower MI suggests lower glial content in the thalamus of these METH-expose children. These findings combined with their poorer performance on VMI also suggest accelerated but aberrant neuronal and glial development in these brain regions.
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Smith LM, Maher AD, Want EJ, Elliott P, Stamler J, Hawkes GE, Holmes E, Lindon JC, Nicholson JK. Large-scale human metabolic phenotyping and molecular epidemiological studies via 1H NMR spectroscopy of urine: investigation of borate preservation. Anal Chem 2009; 81:4847-56. [PMID: 19453167 PMCID: PMC2721977 DOI: 10.1021/ac9004875] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Borate is an antibacterial preservative widely used in clinical and large-scale epidemiological studies involving urine sample analysis. Since it readily forms covalent adducts and reversible complexes with hydroxyl and carboxylate groups, the effects of borate preservation in (1)H NMR-spectroscopy-based metabolic profiling of human urine samples have been assessed. Effects of various concentrations of borate (range 0-30 mM) on (1)H NMR spectra of urine were observed at sequential time points over a 12 month period. Consistent with known borate chemistry, the principal alterations in the (1)H resonance metabolite patterns were observed for compounds such as mannitol, citrate, and alpha-hydroxyisobutyrate and confirmed by ESI-MS analysis. These included line-broadening, T(1) and T(2) relaxation, and chemical shift changes consistent with complex formation and chemical exchange processes. To further investigate complexation behavior in the urinary metabolite profiles, a new tool for visualization of multicomponent relaxation variations in which the spectra were color-coded according to the T(1) and T(2) proton relaxation times respectively (T(1) or T(2) ordered projection spectroscopy, TOPSY) was also developed and applied. Addition of borate caused a general decrease in (1)H T(1) values, consistent with nonspecific effects such as solution viscosity changes. Minor changes in proton T(2) relaxation rates were observed for the most strongly complexing metabolites. From a molecular phenotyping and epidemiologic viewpoint, typical interpersonal biological variation was shown to be vastly greater than any variation introduced by the borate complexation, which had a negligible effect on the metabolic mapping and classification of samples. While caution is indicated in the assignment of biomarker signals where metabolites have diol groupings or where there are adjacent hydroxyl and carboxylate functions, it is concluded that borate preservation is "fit-for-purpose" for (1)H NMR-based epidemiological studies, since the essential biochemical classification features of the samples are robustly maintained.
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Paiman S, Gao Q, Tan HH, Jagadish C, Pemasiri K, Montazeri M, Jackson HE, Smith LM, Yarrison-Rice JM, Zhang X, Zou J. The effect of V/III ratio and catalyst particle size on the crystal structure and optical properties of InP nanowires. NANOTECHNOLOGY 2009; 20:225606. [PMID: 19436086 DOI: 10.1088/0957-4484/20/22/225606] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
InP nanowires were grown on 111B InP substrates by metal-organic chemical vapour deposition in the presence of colloidal gold particles as catalysts. Transmission electron microscopy and photoluminescence measurements were carried out to investigate the effects of V/III ratio and nanowire diameter on structural and optical properties. Results show that InP nanowires grow preferably in the wurtzite crystal structure than the zinc blende crystal structure with increasing V/III ratio or decreasing diameter. Additionally, time-resolved photoluminescence (TRPL) studies have revealed that wurtzite nanowires show longer recombination lifetimes of approximately 2500 ps with notably higher quantum efficiencies.
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Duncton MA, Piatnitski Chekler EL, Katoch-Rouse R, Sherman D, Wong WC, Smith LM, Kawakami JK, Kiselyov AS, Milligan DL, Balagtas C, Hadari YR, Wang Y, Patel SN, Rolster RL, Tonra JR, Surguladze D, Mitelman S, Kussie P, Bohlen P, Doody JF. Arylphthalazines as potent, and orally bioavailable inhibitors of VEGFR-2. Bioorg Med Chem 2009; 17:731-40. [DOI: 10.1016/j.bmc.2008.11.049] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2008] [Revised: 11/15/2008] [Accepted: 11/18/2008] [Indexed: 12/27/2022]
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Hewaparakrama KP, Mackowski S, Jackson HE, Smith LM, Heiss W, Karczewski G. Tuning spin properties of excitons in single CdTe quantum dots by annealing. NANOTECHNOLOGY 2008; 19:125706. [PMID: 21817747 DOI: 10.1088/0957-4484/19/12/125706] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Using polarization-resolved photoluminescence imaging in external magnetic fields we measure statistically significant distributions of exchange splitting, diamagnetic shift and effective g-factor of excitons in tens of single CdTe quantum dots. Comparison between the as-grown and annealed structures shows strong suppression of ensemble inhomogeneities, with the average exchange splitting reduced by half and significant narrowing of the g-factor distribution. Remarkably, the average value of the excitonic g-factor remains unchanged. This unique ability to yield highly uniform quantum dot ensembles without hampering the exciton Zeeman splitting makes annealing a highly attractive means for tuning the spin properties of quantum dot excitons.
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Smith LM, Appel AG. Comparison of several traps for catching German cockroaches (Dictyoptera: Blattellidae) under laboratory conditions. JOURNAL OF ECONOMIC ENTOMOLOGY 2008; 101:151-158. [PMID: 18330130 DOI: 10.1603/0022-0493(2008)101[151:costfc]2.0.co;2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
German cockroach, Blattella germanica (L.) (Dictyoptera: Blattellidae), catch by five types of traps and modifications of each, were tested under controlled laboratory conditions. Cockroach catch differed significantly among traps. Lo-line trap caught the greatest number of cockroaches in the test arena for each size class (23% small nymphs, 39% of gravid females, and 60% of other size classes in the experimental arena). Jar traps caught the least number of cockroaches in the test arena for each size class (range, 7-23% of each size class trapped). Modifications of traps also altered catch of cockroaches. Food bait tablets increased catch significantly; however, increases were small (<10%). Size of traps did not affect catch; whole traps or half traps caught the same number of cockroaches. Jar traps were much less effective than sticky traps, catching only half the number of cockroaches as sticky traps. A thin layer of petrolatum was a more effective barrier in jar traps to cockroach escape than powdered Olancha clay. Traps with petrolatum caught about twice as many cockroaches as traps with clay. Trapping of any of six life stages was not significantly affected by catch of any of the other stages. Rather, trap catch of each life stage was dependent on the number of that life stage available in the experimental arenas. In conclusion, of the traps tested, the Lo-line trap was the most sensitive for measuring cockroach catch, whereas the Detector trap (one third of trap) was the most economical trap (greatest sensitivity for lowest cost).
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Smith LM, Maher AD, Cloarec O, Rantalainen M, Tang H, Elliott P, Stamler J, Lindon JC, Holmes E, Nicholson JK. Statistical Correlation and Projection Methods for Improved Information Recovery from Diffusion-Edited NMR Spectra of Biological Samples. Anal Chem 2007; 79:5682-9. [PMID: 17585837 DOI: 10.1021/ac0703754] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Although NMR spectroscopic techniques coupled with multivariate statistics can yield much useful information for classifying biological samples based on metabolic profiles, biomarker identification remains a time-consuming and complex procedure involving separation methods, two-dimensional NMR, and other spectroscopic tools. We present a new approach to aid complex biomixture analysis that combines diffusion ordered (DO) NMR spectroscopy with statistical total correlation spectroscopy (STOCSY) and demonstrate its application in the characterization of urinary biomarkers and enhanced information recovery from plasma NMR spectra. This method relies on calculation and display of the covariance of signal intensities from the various nuclei on the same molecule across a series of spectra collected under different pulsed field gradient conditions that differentially attenuate the signal intensities according to translational molecular diffusion rates. We term this statistical diffusion-ordered spectroscopy (S-DOSY). We also have developed a new visualization tool in which the apparent diffusion coefficients from DO spectra are projected onto a 1D NMR spectrum (diffusion-ordered projection spectroscopy, DOPY). Both methods either alone or in combination have the potential for general applications to any complex mixture analysis where the sample contains compounds with a range of diffusion coefficients.
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Ross MG, Smith LM. Assessment of neonatal anemia. J Perinatol 2007; 27:325; author reply 325-6. [PMID: 17453046 DOI: 10.1038/sj.jp.7211695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Crockford DJ, Keun HC, Smith LM, Holmes E, Nicholson JK. Curve-fitting method for direct quantitation of compounds in complex biological mixtures using 1H NMR: application in metabonomic toxicology studies. Anal Chem 2007; 77:4556-62. [PMID: 16013873 DOI: 10.1021/ac0503456] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new software tool has been developed that provides automated measurement of signal intensities in NMR spectra of complex mixtures without using data reduction procedures. The algorithm finds best-fit transformations between signals in reference compound spectra and the corresponding signals in analyte spectra. Unlike other algorithms, it is insensitive to variation in chemical shift and can even be used for relative quantitation of compounds whose identities have not yet been established. Additionally, the parameters of the transformation provide information and error metrics that may assist in the streamlining of quality control. The approach presented is general in scope but has been tested by application to peak quantitation in NMR spectra of biofluids. Replicate NMR measurements of solutions of biologically important compounds at various concentrations were made. Further NMR data were collected on urine samples from human, rat, and mouse, which were "spiked" with reference compound solutions at known concentrations. Finally, existing data from an independent toxicology project involving several hundred samples were analyzed, and the consistency of the measurements for metabolites that give multiple NMR signals was assessed. The results of all these tests give confidence that the technique can be used in automated quantitation of compounds in large NMR data sets with minimal operator intervention.
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Iriarte FB, Balogh B, Momol MT, Smith LM, Wilson M, Jones JB. Factors affecting survival of bacteriophage on tomato leaf surfaces. Appl Environ Microbiol 2007; 73:1704-11. [PMID: 17259361 PMCID: PMC1828813 DOI: 10.1128/aem.02118-06] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2006] [Accepted: 01/09/2007] [Indexed: 11/20/2022] Open
Abstract
The ability of bacteriophage to persist in the phyllosphere for extended periods is limited by many factors, including sunlight irradiation, especially in the UV zone, temperature, desiccation, and exposure to copper bactericides. The effects of these factors on persistence of phage and formulated phage (phage mixed with skim milk) were evaluated. In field studies, copper caused significant phage reduction if applied on the day of phage application but not if applied 4 or 7 days in advance. Sunlight UV was evaluated for detrimental effects on phage survival on tomato foliage in the field. Phage was applied in the early morning, midmorning, early afternoon, and late evening, while UVA plus UVB irradiation and phage populations were monitored. The intensity of UV irradiation positively correlated with phage population decline. The protective formulation reduced the UV effect. In order to demonstrate direct effects of UV, phage suspensions were exposed to UV irradiation and assayed for effectiveness against bacterial spot of tomato. UV significantly reduced phage ability to control bacterial spot. Ambient temperature had a pronounced effect on nonformulated phage but not on formulated phages. The effects of desiccation and fluorescent light illumination on phage were investigated. Desiccation caused a significant but only slight reduction in phage populations after 60 days, whereas fluorescent light eliminated phages within 2 weeks. The protective formulation eliminated the reduction caused by both of these factors. Phage persistence was dramatically affected by UV, while the other factors had less pronounced effects. Formulated phage reduced deleterious effects of the studied environmental factors.
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Matulonis UA, Campos S, Krasner CN, Duska LR, Penson RT, Falke R, Roche M, Smith LM, Lee H, Seiden MV. Three sequential chemotherapy doublets for the treatment of newly diagnosed advanced müllerian malignancies: The modified triple doublet regimen. Gynecol Oncol 2006; 103:575-80. [PMID: 16806439 DOI: 10.1016/j.ygyno.2006.04.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2005] [Revised: 04/07/2006] [Accepted: 04/10/2006] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Previously, we reported the use of three sequential doublets (Triple Doublets) in the treatment of women with newly diagnosed and advanced stage müllerian malignancies. The surgically defined negative second look operation (SLO) rate to Triple Doublets was 38%. Modifications were made to this treatment regimen that were predicted to reduce toxicity and possibly increase efficacy. METHODS Open label two-cohort study. Patients with a new diagnosis of Stages II-IV müllerian malignancy were eligible. After cytoreductive surgery, patients were treated with three sequential doublets including 3 cycles of carboplatin and gemcitabine, and 3 cycles of carboplatin and paclitaxel, and 3 cycles of doxorubicin and topotecan. After therapy, all women were clinically staged and evaluated at SLO if clinical staging was negative for residual disease. Primary endpoints were toxicity and negative SLO rate with rates of 60% and 40% defined a priori in optimally cytoreduced (cohort 1) and suboptimally cytoreduced or Stage IV (cohort 2), respectively. RESULTS Eighty-five eligible patients were enrolled with a median age of 52 years. Forty-seven and thirty-eight women were in cohorts 1 and 2, respectively. 723 cycles of chemotherapy were delivered with no toxic deaths. Grades 3 and 4 toxicities included neutropenia in 75% of patients and thrombocytopenia in 65% of patients during at least one cycle of therapy. Fever and neutropenia were seen in 3.5% of patients. All Grades 3 and 4 non-hematologic toxicities were seen at a frequency of <10%. Seventy women underwent SLO with a negative SLO rate of 53% with an additional 9% having microscopically positive procedures. Negative SLO rate was 74% in cohort 1 and 36% in cohort 2. CONCLUSIONS Treatment with the modified triple doublet regimen is tolerable with an encouraging pathologic CR rate.
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Ganti AK, Weisenburger DD, Smith LM, Hans CP, Bociek RG, Bierman PJ, Vose JM, Armitage JO. Patients with grade 3 follicular lymphoma have prolonged relapse-free survival following anthracycline-based chemotherapy: the Nebraska Lymphoma Study Group Experience. Ann Oncol 2006; 17:920-7. [PMID: 16524969 DOI: 10.1093/annonc/mdl039] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND The aim of the study was to determine the outcome and clinical features predictive of survival in patients with follicular lymphoma (FL) treated aggressively and to determine the rate of disease-specific mortality in patients with grade 3 FL (FL3). MATERIALS AND METHODS Four hundred and twenty-one patients with FL who were treated with various anthracycline-based chemotherapy regimens were included in this retrospective study. RESULTS Patients with FL3 and a diffuse component of >50% had the worst outcome, with a hazard ratio of dying of 2.2 (95% CI 1.4-3.4) compared with patients with FL1 or FL2, and a ratio of 1.6 (95% CI 1.02-2.5) compared with FL3 with a diffuse component of < or =50% by multivariate analysis (P = 0.0026). Patients with FL3a had an outcome similar to those with FL3b. In patients with FL3 and a diffuse component of < or =50%, the overall and event-free survival curves showed a plateau for patients younger than 60 years of age. However, there were no differences in the cumulative incidence of relapse/progression or lymphoma-specific/treatment-related mortality between the two age groups. CONCLUSIONS Less than half of the patients with FL3 and a diffuse component of < or =50% treated with anthracycline-based combination chemotherapy will relapse and relapses are uncommon after 6 years. Older patients should be offered the same aggressive chemotherapy as younger patients.
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Duncton MAJ, Piatnitski EL, Katoch-Rouse R, Smith LM, Kiselyov AS, Milligan DL, Balagtas C, Wong WC, Kawakami J, Doody JF. Arylphthalazines. Part 2: 1-(Isoquinolin-5-yl)-4-arylamino phthalazines as potent inhibitors of VEGF receptors I and II. Bioorg Med Chem Lett 2006; 16:1579-81. [PMID: 16386418 DOI: 10.1016/j.bmcl.2005.12.045] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2005] [Revised: 12/08/2005] [Accepted: 12/08/2005] [Indexed: 11/24/2022]
Abstract
A novel class of 1-(isoquinolin-5-yl)-4-arylamino-phthalazines is described as inhibitors of vascular endothelial growth factor receptor II (VEGFR-2). Many compounds display VEGFR-2 inhibitory activity with an IC(50) as low as 0.017 microM in an HTRF enzymatic assay. The compounds also inhibit VEGFR-1, a related tyrosine kinase.
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Liu H, Smith LM, Mao Y, Pan W, Xu Y, Burdzovic‐Wizeman S, Duncton MAJ, Wong WC. Efficient Preparation of ((3‐Chloro‐2‐fluoro‐phenyl)‐[7‐methoxy‐8‐(3‐morpholin‐4‐yl‐propoxy)‐10,11‐dihydro‐5‐oxa‐2,4,11‐triaza‐dibenzo(a,d)cyclohepten‐1‐yl]‐amine) for In‐Vivo Study. SYNTHETIC COMMUN 2006. [DOI: 10.1080/00397910500377479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Duncton MAJ, Smith LM, Burdzovic-Wizeman S, Burns A, Liu H, Mao Y, Wong WC, Kiselyov AS. Preparation of Substituted Pyrimido[4,5-b]-1,4-benzoxazepines, Thiazepines, and Diazepines via a Pictet−Spengler Cyclization. J Org Chem 2005; 70:9629-31. [PMID: 16268648 DOI: 10.1021/jo051419g] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[Reaction: see text]. A synthesis of the title compounds, which have found use as inhibitors of certain receptor tyrosine kinases, was achieved using a Pictet-Spengler cyclization as a key step.
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