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Fluorescence Intensity Decay Shape Analysis Microscopy （FIDSAM） for Quantitative and Sensitive Live-Cell Imaging： A Novel Technique for Fluorescence Microscopy of Endogenously Expressed Fusion-Proteins

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Molecular Plant 2010年第3期3卷 555-562页

作者： Frank Schleifenbaum Kirstin Elgass Marcus Sackrow Katharina Caesar kenneth Berendzen Alfred j. Meixner Klaus Hatter Center for Plant Molecular Biology Department of Plant Physiology University of Tubingen Auf der Morgenstelle 1 72076 Tubingen Germany Institute of Physical and Theoretical Chemistry University of Tubingen Auf der Morgenstelle 8 72076 Tubingen Germany

Fluorescent studies of living plant cells such as confocal microscopy and fluorescence lifetime imaging often suffer from a strong autofluorescent background contribution that significantly reduces the dynamic image contrast and the quantitative access to sub-cellular processes at high spatial resolution. Here, we present a novel technique--fluorescence intensity decay shape analysis microscopy （FIDSAM） to enhance the dynamic contrast of a fluorescence image of at least one order of magnitude. The method is based on the analysis of the shape of the fluorescence intensity decay （fluorescence lifetime curve） and benefits from the fact that the decay patterns of typical fluorescence label dyes strongly differ from emission decay curves of autofluorescent sample areas. Using FIDSAM, we investigated Arabidopsis thaliana hypocotyl cells in their tissue environment, which accumulate an eGFP fusion of the plasma membrane marker protein LTI6b （LTI6b-eGFP） to low level. Whereas in conventional confocal fluorescence images, the membranes of neighboring cells can hardly be optically resolved due to the strong autofluorescence of the cell wall, FIDSAM allows for imaging of single, isolated membranes at high spatial resolution. Thus, FIDSAM will enable the sub-cellular analysis of even low-expressed fluorophoretagged proteins in living plant cells. Furthermore, the combination of FIDSAM with fluorescence lifetime imaging provides the basis to study the local physico-chemical environment of fluorophore-tagged biomolecules in living plant cells.

关键词： Cell structure cell walls membrane proteins high-resolution fluorescence microscopy.

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The organization of societal conflicts by pavement ants Tetramorium caespitum： an agent-based model of amine-mediated decision making

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Current Zoology 2016年第3期62卷 277-284页

作者： Kevin M. HOOVER Andrew N. BUBAK Isaac j. LAW j.zmine D. W. YAEGER kenneth j. RENNER j.hn G. SWALLOW Michael j. GREENE Department of Integrative Biology University of Colorado Denver Denver CO 80217-3364 USA Neuroscience Program University of Colorado Anschutz Medical Campus Aurora CO 80045 USA Department of Biology University of South Dakota Vermillion South Dakota 57069 USA

Ant colonies self-organize to solve complex problems despite the simplicity of an individual ant's brain. Pavement ant Tetramorium caespitum colonies must solve the problem of defending the territory that they patrol in search of energetically rich forage. When members of 2 colonies randomly interact at the territory boundary a decision to fight occurs when: 1) there is a mismatch in nestmate recognition cues and 2) each ant has a recent history of high interaction rates with nestmate ants. Instead of fighting, some ants will decide to recruit more workers from the nest to the fighting location, and in this way a positive feedback mediates the development of colony wide wars. In ants, the monoamines serotonin (5-HT) and octopamine (OA) modulate many behaviors associated with colony organization and in particular behaviors associated with nestmate recognition and aggression. In this article, we develop and explore an agent-based model that conceptualizes how individual changes in brain concentrations of 5-HT and OA, paired with a simple threshold-based decision rule, can lead to the development of colony wide warfare. Model simulations do lead to the development of warfare with 91% of ants fighting at the end of 1 h. When conducting a sensitivity analysis, we determined that uncertainty in monoamine concentration signal decay influences the behavior of the model more than uncertainty in the decision-making rule or density. We conclude that pavement ant behavior is consistent with the detection of interaction rate through a single timed interval rather than integration of multiple interactions.

关键词：单胺类神经递质决策规则模型模拟体组织路面介导代理社会

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Does Selection for Seedling Tiller Number in Perennial Biomass Feedstocks Translate to Yield and Quality Improvements in Mature Swards?

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American j.urnal of Plant Sciences 2023年第11期14卷 1223-1234页

作者： Robert B. Mitchell kenneth P. Vogel Susan j. Tunnell j.mes L. Stubbendieck Wheat Sorghum and Forage Research Unit USDA-ARS Lincoln NE USA Department of Agronomy and Horticulture University of Nebraska Lincoln NE USA

Breeding for seedling traits in herbaceous perennial biomass feedstocks that translate into increased biomass yield or quality in established swards could accelerate the development of perennial grass cultivars for bioenergy or forage. In previously reported research, breeding for single large tillers (ST) or multiple tillers (MT, ≥3) six weeks after planting for two generations in big bluestem (Andropogon gerardii Vitman) and switchgrass (Panicum virgatum L.) base populations produced ST and MT populations that differed significantly for seedling and mature plant traits including biomass yield in spaced planted nurseries. Our obj.ctive was to evaluate these ST and MT populations in sward trials to determine the effect of these genetic changes on biomass yield and quality when the plants were grown in competitive sward conditions. Big bluestem monocultures of the base, ST, and MT populations were evaluated at three locations in Nebraska in 2001 and 2002 as randomized complete block experiments with four replicates. Switchgrass monocultures of the base, ST, and MT populations were evaluated in 2003, 2004, and 2005 near Mead, NE as a randomized complete block with six replicates. In both big bluestem and switchgrass, the ST and MT populations did not consistently differ from the base population or each other for biomass yield or forage quality. These results demonstrate the importance of evaluating perennial grasses in sward trials and not relying solely on greenhouse-grown plants or space-planted nurseries to develop selection criteria and make selection decisions.

关键词： Seedling Tiller Number Perennial Biomass

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Intraocular lens power calculation in eyes with previous corneal refractive surgery

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Eye and Vision 2018年第1期5卷 172-181页

作者： Giacomo Savini kenneth j.Hoffer G.B.Bietti Eye Foundation RomeItaly. Stein Eye Institute University of CaliforniaLos AngelesCAUSA.3 St.Mary’s Eye CenterSanta MonicaCAUSA

Background:This review aims to explain the reasons why intraocular lens(IOL)power calculation is challenging in eyes with previous corneal refractive surgery and what solutions are currently available to obtain more accurate ***:After IOL implantation in eyes with previous LASIK,PRK or RK,a refractive surprise can occur because (i)the altered ratio between the anterior and posterior corneal surface makes the keratometric index invalid;(ii)the corneal curvature radius is measured out of the optical zone;and (iii)the effective lens position is erroneously predicted if such a prediction is based on the post-refractive surgery corneal *** methods are currently available to obtain the best refractive outcomes in these eyes,even when the perioperative data(*** corneal power and surgically induced refractive change)are not *** this review,we describe the most accurate methods based on our clinical ***:IOL power calculation after myopic corneal refractive surgery can be calculated with a variety of methods that lead to relatively accurate outcomes,with 60 to 70%of eyes showing a prediction error within 0.50 diopters.

关键词： Cataract Intraocular lens power LASIK PRK Excimer laser Corneal surgery Keratometry

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Biparental behavior in the burying beetle Nicrophorus orbicollis： a role for dopamine？

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Current Zoology 2016年第3期62卷 285-291页

作者： S. Carmen PANAITOF j.zmine D. W. YAEGER j.rod P. SPEER kenneth j. RENNER Department of Biology UniversiW of Nebraska at Keamey Kearney NE 68849 USA Department of Biology University of South Dakota Vermillion SD 57069 USA

Burying beetlesNicrophorus orbicollisexhibit facultative biparental care of young. To reproduce, a male–female burying beetle pair bury and prepare a small vertebrate carcass as food for its altricial young. During a breeding bout, male and female behavior changes synchronously at appropriate times and is coordinated to provide effective care for offspring. Although the ecological and evolutionary factors that shape this remarkable reproductive plasticity are well characterized, the neuromodulation of parental behavior is poorly understood. j.venile hormone levels rise dramatically at the time beetle parents accept and feed larvae, remain highly elevated during the stages of most active care and fall abruptly when care is terminated. However, hormonal fluctuations alone cannot account for this elaborate control of reproduction. The biogenic amines octopamine (OA), dopamine (DA), and serotonin (5-HT) mediate a diversity of insect reproductive and social behaviors. In this study, we measured whole brain monoamine levels in individual male and female burying beetles and compared OA, DA, and 5-HT profiles between breeding (parental) and nonbreeding, unmated beetles. Remarkably, after 24 h of care, when parental feeding rates begin to peak, DA brain levels increase in breeding beetles when compared to nonbreeding controls. In contrast, brain OA and 5-HT levels did not change significantly. These results provide the first evidence for a potential role of DA in the modulation of burying beetle parental behavior.

关键词：双亲行为多巴胺甲虫激素水平 5-HT 5-羟色胺脊椎动物育种过程

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Characterization of ASTER GDEM elevation data over vegetated area compared with lidar data

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International j.urnal of Digital Earth 2015年第3期8卷 198-211页

作者： Wenj.an Ni Guoqing Sun kenneth j.Ranson State Key Laboratory of Remote Sensing Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijingChina Department of Geographical sciences University of MarylandCollege ParkMDUSA Biospheric Sciences Branch NASA’s Goddard Space Flight CenterGreenbeltMDUSA

Current researches based on areal or spaceborne stereo images with very high resolutions(<1 m)have demonstrated that it is possible to derive vegetation height from stereo *** second version of the Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model(ASTER GDEM)is the state-of-the-art global elevation data-set developed by stereo ***,the resolution of ASTER stereo images(15 m)is much coarser than areal stereo images,and the ASTER GDEM is compiled products from stereo images acquired over 10 *** forest disturbances as well as forest growth are inevitable in 10 years time *** this study,the features of ASTER GDEM over vegetated areas under both flat and mountainous conditions were investigated by comparisons with lidar *** factors possibly affecting the extraction of vegetation canopy height considered include(1)co-registration of DEMs;(2)spatial resolution of digital elevation models(DEMs);(3)spatial vegetation structure;and(4)terrain *** results show that the accurate coregistration between ASTER GDEM and national elevation dataset(NED)is necessary over mountainous *** correlation between ASTER GDEM minus NED and vegetation canopy height is improved from 0.328 to 0.43 by degrading resolutions from 1 arc-second to 5 arc-second and further improved to 0.6 if only homogenous vegetated areas were considered.

关键词： vegetation canopy height ASTER GDEM NED photogrammetry stereo-mapping

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Tumor-associated methylation of the putative tumor suppressor Aj.P1 gene and association between decreased Aj.P1 expression and shorter survival in patients with glioma

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Chinese j.urnal of Cancer 2011年第4期30卷 247-253页

作者： David Cogdell Woonbok Chung Yuexin Liu j. Matthew McDonald kenneth Aldape j.an-Pierre j. Issa Gregory N. Fuller Wei Zhang Department of Pathology The University of Texas MD Anderson Cancer Center Houston Texas 77030 USA Department of Leukemia The University of Texas MD Anderson Cancer Center Houston Texas 77030 USA.

Allelic loss of the short arm of chromosome 1 has been observed frequently in a wide spectrum of cancers,most frequently in *** our previous studies,we evaluated 177 oligodendroglial tumor samples and identified the Aj.P1 gene(formerly Shrew1) in the consensus region of ***1 is a transmembrane protein found in adheren j.nctions and functions to inhibit glioma cell adhesion and *** a putative tumor suppressor gene,we did not detect Aj.P1 gene *** subsequent studies,we found that Aj.P1 was underexpressed in oligodendrogliomas relative to normal brain *** analysis revealed the presence of CpG islands in the promoter of *** analysis of the Aj.P1 promoter identified hypermethylation in 21% of oligodendrogliomas(n = 27),and the degree of methylation correlated with low levels of Aj.P1 expression(P = 0.045).The Aj.P1 promoter was also highly methylated in a wide spectrum of cell lines(n = 22),including cell lines of *** of the National Cancer Institute's REMBRANDT dataset,which contains 343 glioma samples,indicated that low Aj.P1 gene expression was associated with decreased ***,both genetic(gene deletion) and epigenetic alterations(promoter methylation) are likely mechanisms that inactivate the putative tumor suppressor Aj.P1 in gliomas,which contributes to poor prognosis.

关键词：甲基化分析脑胶质瘤抑癌基因 P1基因肿瘤患者协会少突胶质细胞

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Uptake and transformation of arsenic during the reproductive life stage of Agaricus bisporus and Agaricus campestris

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j.urnal of Environmental Sciences 2016年第11期28卷 140-149页

作者： Michelle M.Nearing Iris Koch kenneth j.Reimer Environmental Sciences Group Royal Military College of Canada

Fruiting bodies from the Agaricus genus have been found to contain non-toxic arsenobetaine（AB） as a maj.r compound. It is unknown whether AB is formed during the vegetative or reproductive life stages of the fungus, or by the surrounding microbial community, but AB＇s structural similarity to glycine betaine has led to the hypothesis that AB may be adventitiously accumulated as an osmolyte. To investigate the potential formation of AB during the reproductive life stage of Agaricus species, growth substrate and fungi were collected during the commercial growth of Agaricus bisporus and analyzed for arsenic speciation using HPLC-ICP-MS. AB was found to be the maj.r arsenic compound in the fungus at the earliest growth stage of fruiting（the primordium）. The growth substrate mainly contained arsenate（As（V））. The distribution of arsenic in an A. bisporus primordium grown on As（V） treated substrate, and in a mature Agaricus campestris fruiting body collected from arsenic contaminated mine tailings, was mapped using two dimensional XAS imaging. The primordium and stalk of the mature fruiting body were both found to be growing around pockets of substrate material containing higher As concentrations, and AB was found exclusively in the fungal tissues. In the mature A. campestris the highest proportion of AB was found in the cap, supporting the AB as an osmolyte hypothesis. The results have allowed us to pinpoint the fungus life stage at which AB formation takes place,namely reproduction, which provides a direction for further research.

关键词： Arsenobetaine Arsenic Agaricus Fungi HPLC-ICP-MS XAS imaging

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Endoscopic foregut surgery and interventions:The future is *** state-of-the-art and my personal j.urney

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World j.urnal of Gastroenterology 2019年第1期25卷 1-41页

作者： kenneth j.Chang H.H.Chao Comprehensive Digestive Disease Center University of CaliforniaIrvine Medical CenterOrangeCA 92868United States

In this paper, I reviewed the emerging field of endoscopic surgery and present data supporting the contention that endoscopy can now be used to treat many foregut diseases that have been traditionally treated surgically. Within each topic,the content will progress as follows: "lessons learned", "technical considerations"and "future opportunities". Lessons learned will provide a brief background and update on the most current literature. Technical considerations will include my personal experience, including tips and tricks that I have learned over the ***, future opportunities will address current unmet needs and potential new areas of development. The foregut is defined as "the upper part of the embryonic alimentary canal from which the pharynx, esophagus, lung, stomach, liver,pancreas, and part of the duodenum develop". Foregut surgery is well established in treating conditions such as gastroesophageal reflux disease(GERD), achalasia, esophageal diverticula, Barrett's esophagus(BE) and esophageal cancer, stomach cancer, gastric-outlet obstruction, and obesity. Over the past decade, remarkable progress in interventional endoscopy has culminated in the conceptualization and practice of endoscopic foregut surgery for various clinical conditions summarized in this paper. Regarding GERD, there are now several technologies available to effectively treat it and potentially eliminate symptoms, and the need for long-term treatment with proton pump *** the first time, fundoplication can be performed without the need for open or laparoscopic surgery. Long-term data going out 5-10 years are now emerging showing extended durability. In respect to achalasia, per-oral endoscopic myotomy(POEM) which was developed in j.pan, has become an alternative to the traditional Heller's myotomy. Recent meta-analysis show that POEM may have better results than Heller, but the issue of post-POEM GERD still needs to be addressed. There is now a resurgence of endoscopic tre

关键词： Endoscopy Foregut diseases Gastroesophageal reflux disease Endoscopic sleeve gastroplasty Endoscopic submucosal dissection Per-oral endoscopic myotomy Endo-hepatology

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Comparison of reflux esophagitis and its complications between African Americans and non-Hispanic whites

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World j.urnal of Gastroenterology 2009年第23期15卷 2878-2881页

作者： kenneth j.Vega Sian Chisholm M Mazen j.mal Divisions of Gastroenterology and General Internal Medicine University of Florida Health Sciences Center Jacksonville Florida 32207 United States Gastroenterology Section Veterans Affairs Medical Center 5901 E. 7th St. Long Beach CA 90822 United States

AIM: To determine the effect of ethnicity on the severity of reflux esophagitis (RE) and its complications. METHODS: A retrospective search of the endoscopy database at the University of Florida Health Science Center/j.cksonville for all cases of reflux esophagitis and its complications from j.nuary 1 to March 31, 2001 was performed. Inclusion criteria were endoscopic evidence of esophagitis using the LA classif ication, reflux related complications and self-reported ethnicity. The data obtained included esophagitis grade, presence of a hiatal hernia, esophageal ulcer, stricture and Barrett's esophagus, and endoscopy indication. RESULTS: The search identified 259 patients with RE or its complications, of which 171 were non-Hispanic whites and 88 were African Americans. The mean ages and male/female ratios were similar in the two groups. RE grade, esophageal ulcer, stricture and hiatal hernia frequency were likewise similar in the groups. Barrett's esophagus was present more often in non-Hispanic whites than in African Americans (15.8% vs 4.5%; P < 0.01). Heartburn was a more frequent indication for endoscopy in non-Hispanic whites with erosive esophagitis than in African Americans (28.1% vs 7.9%; P < 0.001). CONCLUSION: Distribution of RE grade and frequency of reflux-related esophageal ulcer, stricture andhiatal hernia are similar in non-Hispanic whites and African Americans. Heartburn was more frequently and nausea/vomiting less frequently reported as the primary endoscopic indication in non-Hispanic whites compared with African Americans with erosive esophagitis or its complications. African Americans have a decreased prevalence of Barrett's esophagus compared with non-Hispanic whites.

关键词：西班牙美国人并发症食管

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