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Arabidopsis FtsZ2-1 and FtsZ2-2 Are Functionally Redundant, But FtsZ-Based Plastid Division Is Not Essential for Chloroplast Partitioning or Plant Growth and Development

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Molecular Plant 2009年第6期2卷 1211-1222页

作者： Aaron j. Schmitz jonathan M. Glynn Bradley j.S.C. Olson kevin D. Stokes Katherine W. Osteryoung Department of Plant Biology 166 Plant Biology Bldg Michigan State University East Lansing MI 48824-1312 USA Cell and Molecular Biology Program Michigan State University East Lansing MI 48824 USA Department of Energy-Plant Research Laboratory Michigan State University East Lansing MI 48824 USA Genetics Program Michigan State University East Lansing MI 48824 USA Biochemistry and Molecular Biology Program Michigan State University East Lansing MI 48824 USA Present address: The Salk Institute for Biological Studies Plant Molecular and Cellular Biology Laboratory La Jolla CA 92037 USA Present address: Mycobacteria and Brucella Section NVSL/APHIS/USDA 1920 Dayton Ave Ames IA 50010 USA

FtsZ1 and FtsZ2 are phylogenetically distinct families of FtsZ in plants that co-localize to mid-plastid rings and facilitate division of chloroplasts. In plants, altered levels of either FtsZ1 or FtsZ2 cause dose-dependent defects in chloroplast division; thus, studies on the functional relationship between FtsZgenes require careful manipulation of FtsZ levels in vivo. To define the functional relationship between the two FtsZ2 genes in Arabidopsis thaliana, FtsZ2-1 and FtsZ2-2, we expressed FtsZ2-1 in an ftsZ2-2 null mutant, and vice versa, and determined whether the chloroplast division defects were rescued in plants expressing different total levels of FtsZ2. Full rescue was observed when either the FtsZ2-1 or FtsZ2-2 level approximated total FtsZ2 levels in wild-type （WT）. Additionally, FtsZ2-2 interacts with ARC6, as shown previously for FtsZ2- 1. These data indicate that FtsZ2-1 and FtsZ2-2 are functionally redundant for chloroplast division in Arabidopsis. To rigorously validate the requirement of each FtsZ family for chloroplast division, we replaced FtsZ1 with FtsZ2 in vivo, and vice versa, while maintaining the FtsZ level in the transgenic plants equal to that of the total level in WT. Chloroplast division defects were not rescued, demonstrating conclusively that FtsZ1 and FtsZ2 are non-redundant for maintenance of WT chloroplast numbers. Finally, we generated ftsZtriple null mutants and show that plants completely devoid of FtsZ protein are viable and fertile. As plastids are presumably essential organelles, these findings suggest that an FtsZ-independent mode of plastid partitioning may occur in higher plants.

关键词： Chloroplast plastid division FtsZ ARC6 PDV1.

Families in Botryosphaeriales:aphylogenetic,morphological and evolutionary perspective

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Fungal Diversity 2019年第1期94卷 1-22页

作者： Alan j.L.Phillips kevin D.Hyde Artur Alves jian-Kui(jack)Liu Faculdade de Ciencias Biosystems and Integrative Sciences Institute(BioISI)Universidade de LisboaCampo Grande1749-016 LisbonPortugal Center of Excellence in Fungal Research Mae Fah Luang UniversityChiang Rai 57100Thailand Departamento de Biologia CESAMUniversidade de Aveiro3810-193 AveiroPortugal Guizhou Institute of Biotechnology Guizhou Academy of Agricultural SciencesGuiyang 550006People’s Republic of China

Botryosphaeriales was introduced in 2006 for a single family *** then the number of families has increased as a result of the transfer of one family(Planistromellaceae)into the order,re-instatement of another(Phyllostictaceae),while others resulted from raising genera to family status(Aplosporellaceae,Endomelanconiopsisaceae,Melanopsaceae,Pseudofusicoccumaceae,Saccharataceae and Septorioideaceae).All these decisions were based solely on phylogenetic analyses of several different *** has been no consensus on which loci are suitable markers at this taxonomic level and in some cases the datasets used to construct the phylogenies were *** this paper,the families of Botryosphaeriales were re-assessed in terms of morphology of the sexual morphs,phylogenetic relationships based on ITS and LSU sequence data,and evolutionary divergence times of lineages in relation to major events in the evolution of their hosts on a geological *** main lineages were resolved in the phylogenetic analyses and these correspond to six groups as defined on morphology of the sexual *** lineages evolved during the Late epoch of the Cretaceous period and survived the catastrophic event that led to the mass extinction of non-avian dinosaurs and a great loss of plant diversity at the end of the Cretaceous *** then diversified during the Paleocene and Eocene epochs of the Paleogene *** six lineages are considered to represent families in ***,six families(Aplosporellaceae,Botryosphaeriaceae,Melanopsaceae,Phyllostictaceae,Planistromellaceae and Saccharataceae)are accepted in Botryosphaeriales,while three(Endomelanconiopsisaceae,Pseudofusicoccumaceae and Septorioideaceae)are reduced to synonymy under existing families.

关键词： Classification Dothideomycetes Evolutionary divergence times Morphology

Analysis of an Ensemble of High-Resolution WRF Simulations for the Rapid Intensification of Super Typhoon Rammasun(2014)

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Advances in Atmospheric Sciences 2020年第2期37卷 187-210页

作者： Xun LI Noel EDAVIDSON Yihong DUAN kevin jTORY Zhian SUN Qinbo CAI Key Laboratory of South China Sea Meteorological Disaster Prevention and Mitigation of Hainan Province China Meteorological AdministrationHaikouHainan 570203China Hainan Meteorological Services China Meteorological AdministrationHaikouHainan 570203China Research and Development Branch Bureau of MeteorologyMelbourne 3001Australia State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China

Diagnostics are presented from an ensemble of high-resolution forecasts that differed markedly in their predictions of the rapid intensification(RI)of Typhoon *** show that the basic difference stems from subtle differences in initializations of(a)500-850-h Pa environmental winds,and(b)midlevel moisture and *** then describe how these differences impact on the evolving convective organization,storm structure,and the timing of *** expected,ascent,diabatic heating and the secondary circulation near the inner-core are much stronger in the member that best forecasts the *** evolution of vortex cloudiness from this member is similar to the actual imagery,with the development of an inner cloud band wrapping inwards to form the *** present evidence that this structure,and hence the enhanced diabatic heating,is related to the tilt and associated dynamics of the developing inner-core in *** the most accurate ensemble member:(a)inhibition of ascent and a reduction in convection over the up-shear sector allow moistening of the boundary-layer air,which is transported to the down-shear sector to feed a developing convective asymmetry;(b)with minimal ventilation,undiluted clouds and moisture from the down-shear left quadrant are then wrapped inwards to the up-shear left quadrant to form the eyewall cloud;and(c)this process seems related to a critical down-shear tilt of the vortex from midlevels,and the vertical phase-locking of the circulation over up-shear *** the member that forecasts a much-delayed RI,these processes are inhibited by stronger vertical wind shear,initially resulting in poor vertical coherence of the circulation,lesser moisture and larger *** analysis suggests that ensemble prediction is needed to account for the sensitivity of forecasts to a relatively narrow range of environmental wind shear,moisture and vortex inner-structure.

关键词： typhoons rapid intensification ensemble simulation spin-up processes ventilation vertical wind shear

Accuracy of biometric formulae for intraocular lens power calculation in a teaching hospital

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International journal of Ophthalmology(English edition) 2020年第1期13卷 61-65页

作者： kevin S Tang Elaine M Tran Allison j Chen David R Rivera jorge j Rivera Paul B Greenberg Division of Ophthalmology Alpert Medical SchoolBrown UniversityProvidence 02903Rhode IslandUSA Section of Ophthalmology Providence VA Medical CenterProvidence 02908Rhode IslandUSA Shiley Eye Institute and Department of Ophthalmology University of California San DiegoLa Jolla 92093CaliforniaUSA

AIM: To evaluate the accuracy of three commonly used biometric formulae across different axial lengths(ALs) at one United States Veterans Affairs teaching ***: A retrospective chart review was conducted from November 2013 to May 2018. One eye of each patient who underwent cataract surgery with a monofocal intraocular lens(IOL) was included. The range of postoperative follow-up period was from 3 wk to 4 mo. The Holladay 2, Barrett Universal II, and Hill-Radial Basis Function(Hill-RBF) formulae were used to predict the postoperative refraction for all cataract surgeries. For each formula, we calculated the prediction errors [including mean absolute prediction error(MAE)] and the percentage of eyes within ±0.25 diopter(D) and ±0.5 D of predicted refraction. We performed subgroup analyses for short(AL25.0 mm).RESULTS: A total of 1131 patients were screened, and 909 met the inclusion criteria. Resident ophthalmologists were the primary surgeons in 710(78.1%) cases. We found no statistically significant difference in predictive accuracy among the three formulae over the entire AL range or in the short, medium, and long eye subgroups. Across the entire AL range, the Hill-RBF formula resulted in the lowest MAE(0.384 D) and the highest percentage of eyes with postoperative refraction within ±0.25 D(42.7%) and ±0.5 D(75.5%) of predicted. All three formulae had the highest MAEs(>0.5 D) and lowest percentage within ±0.5 D of predicted refraction(<55%) in short ***: In cataract surgery patients at our teaching hospital, three commonly used biometric formulae demonstrate similar refractive accuracy across all ALs. Short eyes pose the greatest challenge to predicting postoperative refractive error.

关键词： cataract surgery biometry intraocular lens power calculation

Stable isotope evidence for trophic niche partitioning in a South African savanna rodent community

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Current Zoology 2015年第3期61卷 397-411页

作者： jacqueline CODRON kevin j DUFFY Nico L AVENANT Matt SPONHEIMER jennifer LEICHLITER Oliver PAINE Paul SANDBERG Daryl CODRON Institute of Systems Science Durban University of Technology Durban South Africa Karoo Palaeontology Deparlnaent National Museum PO Box 266 Bloemfontein 9301 RSA School of Mathematics Statistics and Computer Science University of KwaZulu-Natal Private Bag X01 Scottsville 3209 RSA Denartment of Mammalogv. National Museum. PO Box 266. Bloemfontein 9301. RSA Department of Anthropology University of Colorado at Boulder Boulder CO80309 USA Florisbad Quaternary Research Department National Museum PO Box 266 Bloemfontein 9301 RSA

Species’ partitioning of resources remains one of the most integral components for understanding community assembly. Analysis of stable carbon and nitrogen isotopes in animal tissues has the potential to help resolve patterns of partitioning because these proxies represent the individual’s diet and trophic niche, respectively. Using free-ranging rodents in a southern African savanna as a model community, we find that syntopic species within habitats occupy distinct isotope niches. Moreover, species with strongly overlapping isotope niches did not overlap in their spatial distribution patterns, suggesting an underlying effect of competitive exclusion. Niche conservatism appears to characterize the behaviour of most species in our sample - with little or no observed changes across habitats - with the exception of one species,Mastomys coucha. This species displayed a generalist distribution, being found in similar abundances across a variety of habitats. This spatial pattern was coupled with a generalist isotope niche that shifted across habitats, likely in response to changes in species composition over the same spatial gradient. The case forM. couchasupports contentions that past competition effects played a significant evolutionary role in shaping community structures of today, including the absence of strong interspecific niche overlaps within particular habitats. Our study highlights the value of stable isotope approaches to help resolve key questions in community ecology, and moreover introduces novel analytical approaches to quantifying isotope niche breadths and niche overlaps that are easily comparable with traditional metrices.

关键词：稳定同位素方法营养生态位鼠类群落稀树草原生态位重叠物种组成证据南非

Catheter-based renal sympathetic nerve denervation on hypertension management outcomes

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World journal of Radiology 2022年第7期14卷 238-248页

作者： Som P Singh kevin j Varghese Fahad M Qureshi Macy C Anderson john Foxworth Mark M Knuepfer Department of Internal Medicine University of Missouri Kansas City School of MedicineKansas CityMO 64106United States Department of Pharmacological and Physiological Science Saint Louis University School of MedicineSaint LouisMO 63104United States

BACKGROUND Renal sympathetic denervation(RSD)provides a minimally invasive interventional treatment modality for patients with resistant ***,the post-operative outcomes remain a key area of investigation since its earliest clinical *** To evaluate patient outcomes after RSD intervention among peer-reviewed patient *** A systematic review of literature on MEDLINE,Google Scholar,and the Cochrane Database of Systematic Reviews for RSD case studies to assess post-operative hypertension readings and medical *** Among 51 RSD cases,the post-operative RSD patients report an apparent reduction with a mean number of 3.1 antihypertensive *** mean systolic arterial blood pressure 1 year following RSD was 136.0 mmHg(95%CI:118.7-153.3).CONCLUSION The apparent improvements in office systolic blood pressure after 12 month postoperative RSD can support the therapeutic potential of this intervention for blood pressure *** studies which utilized a uniform methodology for blood pressure measurement can further support the findings of this systematic review.

关键词： Renal denervation Hypertension Systematic review Interventional radiology Outcomes

Managing extremely distal periprosthetic femoral supracondylar fractures of total knee replacements-a new PHILOS-ophy

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World journal of Orthopedics 2017年第10期8卷 809-813页

作者： kevin j Donnelly Adam Tucker Angel Ruiz Neville W Thompson Department of Trauma and Orthopaedic Surgery Altnagelvin Hospital

We report two cases where a proximal humeral locking plate was used for the fixation of an extremely distal, type Ⅲ peri-prosthetic femoral fractures in relation to a total knee replacement(TKR). In each case there was concern regarding the fixation that could be achieved using the available anatomic distal femoral plates due to the size and bone quality of distal fragment. The design of the Proximal Humeral Internal Locking System(PHILOS) allows nine 3.5-mm locking screws to be placed over a small area in multiple directions. This allowed a greater number of fixation points to be achieved in the distal fragment. Clinical and radiological short-term follow-up(6-12 mo) has been satisfactory in both cases with no complications. We suggest the use of this implant for extremely distal femoral fractures arising in relation to the femoral component of a TKR.

关键词： Distal Femoral Periprosthetic Fracture PHILOS Open reduction and internal fixation

Role of microbial dysbiosis in the pathogenesis of esophageal mucosal disease:A paradigm shift from acid to bacteria?

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World journal of Gastroenterology 2021年第18期27卷 2054-2072页

作者： Steve M D'Souza kevin Houston Lauren Keenan Byung Soo Yoo Parth j Parekh David A johnson Department of Internal Medicine Division of GastroenterologyEastern Virginia Medical SchoolNorfolkVA 23502United States

Genomic sequencing,bioinformatics,and initial speciation(e.g.,relative abundance)of the commensal microbiome have revolutionized the way we think about the“human”body in health and *** interactions between the gut bacteria and the immune system of the host play a key role in the pathogenesis of gastrointestinal diseases,including those impacting the *** relatively stable,there are a number of factors that may disrupt the delicate balance between the luminal esophageal microbiome(EM)and the *** changes are thought to be a product of age,diet,antibiotic and other medication use,oral hygiene,smoking,and/or expression of antibiotic products(bacteriocins)by other *** effects may lead to persistent dysbiosis which in turn increases the risk of local inflammation,systemic inflammation,and ultimately disease *** has suggested that the etiology of gastroesophageal reflux disease-related esophagitis includes a cytokine-mediated inflammatory component and is,therefore,not merely the result of esophageal mucosal exposure to corrosives(i.e.,acid).Emerging evidence also suggests that the EM plays a major role in the pathogenesis of disease by inciting an immunogenic response which ultimately propagates the inflammatory ***,we discuss the potential role for manipulating the EM as a therapeutic option for treating the root cause of various esophageal disease rather than just providing symptomatic relief(i.e.,acid suppression).

关键词： Microbiome Gastroesophageal reflux disease Probiotics Prebiotics Bacteriocins Dysbiosis Barrett’s esophagus Esophageal cancer Esophagitis Eosinophilic esophagitis

Brain-targeting,acid-responsive antioxidant nanoparticles for stroke treatment and drug delivery

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Bioactive Materials 2022年第10期7卷 57-65页

作者： Shenqi Zhang Bin Peng Zeming Chen jiang Yu Gang Deng Youmei Bao Chao Ma Fengyi Du Wendy C.Sheu W.Taylor Kimberly j.Marc Simard Daniel Coman Qianxue Chen Fahmeed Hyder jiangbing Zhou kevin N.Sheth Department of Neurosurgery USA Department of Biomedical Engineering USA Department of Radiology and Biomedical Imaging USA Department of Neurology Yale UniversityNew HavenCT06510USA Department of Neurosurgery Renmin Hospital of Wuhan UniversityWuhanHubei430060China Department of Neurology Division of Neurocritical CareMassachusetts General HospitalBostonMAUSA Department of Neurosurgery University of Maryland School of MedicineBaltimoreMD21201USA

Stroke is the leading cause of death and ***,there is no effective pharmacological treatment for this disease,which can be partially attributed to the inability to efficiently deliver therapeutics to the *** we report the development of natural compound-derived nanoparticles(NPs),which function both as a potent therapeutic agent for stroke treatment and as an efficient carrier for drug delivery to the ischemic ***,we screened a collection of natural nanomaterials and identified betulinic acid(BA)as one of the most potent antioxidants for stroke ***,we engineered BA NPs for preferential drug release in acidic ischemic tissue through chemically converting BA to betulinic amine(BAM)and for targeted drug delivery through surface conjugation of AMD3100,a CXCR4 *** resulting AMD3100-conjugated BAM NPs,or A-BAM NPs,were then assessed as a therapeutic agent for stroke treatment and as a carrier for delivery of NA1,a neuroprotective *** show that intravenous administration of A-BAM NPs effectively improved recovery from stroke and its efficacy was further enhanced when NA1 was *** to their multifunctionality and significant efficacy,we anticipate that A-BAM NPs have the potential to be translated both as a therapeutic agent and as a drug carrier to improve the treatment of stroke.

关键词： Drug delivery Acid-triggered release Antioxidant nanoparticles NA1 Ischemic stroke