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The Dynamic Pollen Tube Cytoskeleton： Live Cell Studies Using Actin-Binding and Microtubule- Binding Reporter Proteins

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Molecular Plant 2008年第4期1卷 686-702页

作者： alice Y. Cheung Qiao-hong Duan Silvia Santos costa Barend H.J. de Graaf Veronica S. DiStilio Jose feijo Hen-Ming Wu Department of Biochemistry and Molecular Biology Molecular Cell Biology Program Plant Biology Graduate Program University of Massachusetts Lederle Graduate Research Tower Amherst MA 01003 USA Instituto Gulbenkian de Ciencia Centro de Biologia de Desenvolvimento PT-2780-156 Oeiras Portugal Universidale de Lisboa Faculdade de Ciencias Dept. Biologia Vegetal Campo Grande Ed.C2. PT-1749-016 Lisboa Portugal Present address: School of Biosciences University of Birmingham Edgbaston B15 2TT UK Present address: Department of Biology University of Washington Box 351800 Seattle WA 98195 USA

Pollen tubes elongate within the pistil to transport sperm cells to the embryo sac for fertilization. Growth occurs exclusively at the tube apex, rendering pollen tube elongation a most dramatic polar cell growth process. A hall- mark pollen tube feature is its cytoskeleton, which comprises elaborately organized and dynamic actin microfilaments and microtubules. Pollen tube growth is dependent on the actin cytoskeleton; its organization and regulation have been examined extensively by various approaches, including fluorescent protein labeled actin-binding proteins in live cell studies. Using the previously described GfP-NtADf1 and GfP-LIADf1, and a new actin reporter protein NtPLIM2b-GfP, we re-affirm that the predominant actin structures in elongating tobacco and lily pollen tubes are long, streaming actin cables along the pollen tube shank, and a subapical structure comprising shorter actin cables. The subapical collection of actin microfilaments undergoes dynamic changes, giving rise to the appearance of structures that range from basket- or funnel-shaped, mesh-like to a subtle ring. NtPLIM2b-GfP is used in combination with a guanine nucleotide exchange factor for the Rho GTPases, AtRoP-GEf1, to illustrate the use of these actin reporter proteins to explore the linkage between the polar cell growth process and its actin cytoskeleton. Contrary to the actin cytoskeleton, microtubules appear not to play a direct role in supporting the polar cell growth process in angiosperm pollen tubes. Using a microtubule reporter protein based on the microtubule end-binding protein from Arabidopsis AtEB1, GfP-AtEB1, we show that the extensive microtubule network in elongating pollen tubes displays varying degrees of dynamics. These reporter proteins provide versatile tools to explore the functional connection between major structural and signaling components of the polar pollen tube growth process.

关键词： Dynamic Pollen Tube Cytoskeleton Live Cell Studies Using Actin-Binding Microtubule-Binding Reporter Proteins

Growing Burden of Hypertension in China: Causes, Challenges, and opportunities

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China CDC weekly 2020年第40期2卷 776-779页

作者： Zumin Shi Xiaomin Sun alice f Yan Youfa Wang Human Nutrition Department College of Health SciencesQU HealthQatar UniversityQatar Global Health Institute School of Public HealthXi’an Jiaotong University Health Science CenterXi’anShaanxiChina Center for Advancing Population Science Division of General Internal MedicineDepartment of MedicineMedical College of WisconsinMilwaukeeWIUSA

Cardiovascular disease(CVD)is the leading cause of death in China,and an estimated 290 million individuals are affected by CVD in China(1).Hypertension is the most important risk factor of CVD(2).Good control and management of hypertension are vital to prevent CVD and related health and social *** the past several decades,China has put a significant amount of effort into the battle against ***,the burden of hypertension continues to ***,we described the burden of hypertension and its important risk factors in China.

关键词： hypertension death consequences

Consecutive fecal calprotectin measurements for predicting relapse in pediatric Crohn's disease patients

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World Journal of Gastroenterology 2019年第10期25卷 1266-1277页

作者： alice Jane foster Matthew Smyth Alam Lakhani Benjamin Jung Rollin f Brant Kevan Jacobson Division of Gastroenterology Hepatology and NutritionBritish Columbia Children’s Hospital Pediatrics B.C.Children’s Hospital Research Institute Pediatrics British Columbia children’s HospitalUniversity of British Columbia Department of Statistics University of British Columbia Department of Cellular and Physiological Sciences Faculty of Medicine

BACKGRoUND Asymptomatic children with Crohn's disease(CD) require ongoing monitoring to ensure early recognition of a disease *** In a cohort of pediatric CD patients, we aimed to assess the utility of serial fecal calprotectin measurements to detect intestinal inflammatory activity and predict disease *** In this prospective longitudinal cohort study, children with CD on infliximab therapy in clinical remission were included. fecal calprotectin levels were assessed at baseline and at subsequent 2-5 visits. Clinical and biochemical disease activity were assessed using the Pediatric Crohn's Disease Activity Index, Creactive protein and erythrocyte sedimentation rate at baseline and at visits over the following 18 *** 53 children were included and eighteen patients(34%) had a clinical disease relapse during the study. Baseline fecal calprotectin levels were higher in patients that developed symptomatic relapse [median(interquartile range), relapse 723μg/g(283-1758) vs 244 μg/g(61-627), P = 0.02]. fecal calprotectin levels > 250μg/g demonstrated good predictive accuracy of a clinical flare within 3 mo(area under the receiver operator curve was 0.86, 95% confidence limits 0.781 to 0.937).CoNCLUSIoN Routine fecal calprotectin testing in children with CD in clinical remission is useful to predict relapse. Levels > 250 μg/g are a good predictor of relapse in the following 3 mo. This information is important to guide monitoring standards used in this population.

关键词： fecal calprotectin Disease relapse Biomarker Crohn’s disease Children

Interference screws *** anchors for isolated medial patellofemoral ligament femoral fixation:A systematic review

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Journal of Sport and Health Science 2022年第1期11卷 123-129页

作者： filippo Migliorini alice Baroncini Jörg Eschweiler Markus Tingart Nicola Maffulli Department of orthopaedics University Clinic AachenRheinisch-Westfälische Technische Hochschule(RWTH)Aachen University ClinicAachen 52074Germany Department of Medicine Surgery and DentistryUniversity of SalernoBaronissi 84081Italy School of Pharmacy and Bioengineering School of MedicineKeele UniversityStoke on Trent ST47QBUK Centre for Sports and Exercise Medicine Barts and the London School of Medicine and DentistryMile End HospitalQueen Mary University of LondonLondon E14DGUK

Purpose:The present study aimed to systematically review and compare 2 femoral autograft fixation techniques,namely,interference screws and suture anchors,for isolated medial patellofemoral ligament reconstruction in patients with recurrent patellofemoral instability at mid-to long-term ***:A literature search was performed in September *** studies reporting the outcomes of primary isolated medial patellofemoral ligament reconstruction for recurrent patellofemoral instability were considered for *** studies reporting the type of femoral autograft fixation under examination were *** reporting data from patients with elevated tibial tuberosity-tibial groove,patella alta,and/or Dejour’s trochlear dysplasia types C and D,were not *** articles reporting data with a minimum follow-up period of 18 months were ***:Data from 19 studies(615 patients)were *** overall age was 24.4±6.7 years(mean±SD).The mean follow-up was 46.5±20.9 *** were 76 patients in the anchor group and 539 in the screw *** was found with regard to age and follow-up duration between the 2 study *** was comparability between the Kujala,Lysholm,and Tegner scores at *** the last follow-up,no worthy differences were found in terms of mean Kujala(+2.1%;p=0.04),Lysholm(+1.7%;p=0.05),and Tegner(+15.8%;p=0.05)*** complications occurred almost exclusively in the screw cohort,no statistically significant difference was ***:femoral autograft fixation through interference screws or suture anchors report similar clinical scores and rate of apprehension test,persistent joint instability,re-dislocations,and *** results must be interpreted within the limitations of the present study.

关键词： femoral fixation Medial patellofemoral ligament reconstruction Patellofemoral instability

Hard to fly the nest： A study of body condition and plumage quality in house sparrow fledglings

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Current Zoology 2014年第4期60卷 449-459页

作者： Charlene LELoUTRE alice GoUZERH frederic ANGELIER Centre d'Etudes Biologiques de Chiz6 CNRS F-79360 Villiers en Bois France

Contrary to the nestling phase, the post-fledging phase has been less studied probably because it is challenging to follow the chicks after they fledge. However, this phase is crucial to consider when focusing on the life cycle of individuals because it is associated with new demands： After leaving the nest, individuals have to find their own food and cope with a new set of previously unknown stressors. In this study, we aimed at better understanding how energetically demanding the post-ftedging period is in house sparrows Passer domesticus by measuring several indices of a fledgling＇s state （body condition, fat and muscle scores and plumage quality）. If the energetic demands of the post-fledging period are greater than those of the adult life, we predicted that fledglings should be in lower condition and should have a plumage of lower quality relative to adults. Supporting this prediction, the condition and the plumage of fledglings differed dramatically from those of adults. Interestingly, this difference disappeared in autumn. overall, our results suggest that the post-fledging period is probably one of the most energetically demanding of the life cycle in this species. Supporting this idea, the resighting probability of fledglings was lower relative to adults. However, resighting probability depends on many factors （mortality, dispersal, habitat use and behaviours） and future studies are necessary to tease apart their relative importance in determining resighting probability [Current Zoology 60 （4）： 449-459, 2014].

关键词： Body condition fault bar fat score Muscle score Passer domesticus

Novel Contiguous Cross Propagation Neural Network Built CAD for Lung Cancer

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Computer Systems Science & Engineering 2023年第2期44卷 1467-1484页

作者： A.alice Blessie P.Ramesh Department of Electronics&Communication Engineering Government College of EngineeringTirunelveli627007TamilnaduIndia Department of Electrical&Electronics Engineering University College of EngineeringRamanathapuram623513TamilnaduIndia

The present progress of visual-based detection of the diseased area of a malady plays an essential part in the medicalﬁ*** that case,the image proces-sing is performed to improve the image data,wherein it inhibits unintended dis-tortion of image features or it enhances further processing in various applications andﬁ*** helps to show better results especially for diagnosing *** late the early prediction of cancer is necessary to prevent disease-causing *** work is proposed to identify lung cancer using lung computed tomo-graphy(CT)scan *** helps to identify cancer cells’affected *** the present work,the original input image from Lung Image Database Consortium(LIDC)typically suffers from noise *** overcome this,the Gaborﬁlter used for image processing is highly *** the next stage,the Spherical Iterative Reﬁnement Clustering(SIRC)algorithm identiﬁes cancer-suspected areas on the CT scan *** approach can help radiologists and medical experts recognize cancer diseases and syndromes so that serious progress can be avoided in the early *** new methods help to remove unwanted por-tions of the CT image and better utilization the *** subspace extraction of features approach is beneﬁcial for evaluating lung *** paper introduces a novel approach called Contiguous Cross Propagation Neural Network that tends to locate regions afﬂicted by lung cancer using CT scan pictures(CCPNN).By using the feature values from the fourth step of the procedure,the proposed CCPNN tends to categorize the lesion in the lung nodular *** efﬁciency of the suggested CCPNN approach is evaluated using classiﬁcation metrics such as recall(%),precision(%),f-measure(percent),and accuracy(%).finally,the incorrect classiﬁcation ratios are determined to compare the trained networks’effectiveness,through these parameters of CCPNN,it obtains the outstanding per-formance of 98.06%and it has provided the lowest false ratio of

关键词： Contiguous cross propagation neural network(CCPNN) Gaborﬁlter

Metabolic collaboration between cells in the tumor microenvironment has a negligible effect on tumor growth

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The Innovation 2024年第2期5卷 107-114页

作者： Johan Gustafsson fariba Roshanzamir Anders Hagnestål Sagar M.Patel oseeyi I.Daudu Donald f.Becker Jonathan L.Robinson Jens Nielsen Department of Life Sciences Chalmers University of TechnologySE-41296 GothenburgSweden Hagnesia AB SE-43854 HindåsSweden Department of Biochemistry and Redox Biology Center University of Nebraska-LincolnLincolnNE 68588USA BioInnovation Institute DK2200 CopenhagenDenmark

The tumor microenvironment is composed of a complex mixture of different cell types interacting under conditions of nutrient deprivation,but the metabolism therein is not fully understood due to difficulties in measuring metabolic fluxes and exchange of metabolites between different cell types in ***-scale metabolic modeling enables estimation of such exchange fluxes as well as an opportunity to gain insight into the metabolic behavior of individual cell ***,we estimated the availability of nutrients and oxygen within the tumor microenvironment using concentration measurements from blood together with a metabolite diffusion *** addition,we developed an approach to efficiently apply enzyme usage constraints in a comprehensive metabolic model of human *** combined modeling reproduced severe hypoxic conditions and the Warburg effect,and we found that limitations in enzymatic capacity contribute to cancer cells’preferential use of glutamine as a substrate to the citric acid ***,we investigated the common hypothesis that some stromal cells are exploited by cancer cells to produce metabolites useful for the cancer *** identified over 200 potential metabolites that could support collaboration between cancer cells and cancer-associated fibroblasts,but when limiting to metabolites previously identified to participate in such collaboration,no growth advantage was *** work highlights the importance of enzymatic capacity limitations for cell behaviors and exemplifies the utility of enzyme-constrained models for accurate prediction of metabolism in cells and tumor microenvironments.

关键词： metabolism effect limitations

Numerical Approximation of oscillatory Solutions of Hyperbolic-Elliptic Systems of Conservation Laws by Multiresolution Schemes

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Advances in Applied Mathematics and Mechanics 2009年第5期1卷 581-614页

作者： Stefan Berres Raimund Burger alice Kozakevicius Departamento de Ciencias Matematicas y fısicas Universidad Catolica de TemucoTemucoChile CI2MA and Departamento de Ingenier´ıa Matem´atica Facultad de Ciencias Fısicas y Matem´aticasUniversidad de Concepci´onCasilla 160-CConcepci´onChile Departamento de Matematica-CCNE Universidade Federal de Santa MariaAv.Roraima1000Campus Universit´arioSanta MariaRSCEP 97105-900Brazil

The generic structure of solutions of initial value problems of hyperbolic-elliptic systems,also called mixed systems,of conservation laws is not yet fully *** reason for the absence of a core well-posedness theory for these equations is the sensitivity of their solutions to the structure of a parabolic regularization when attempting to single out an admissible solution by the vanishing viscosity *** is,however,theoretical and numerical evidence for the appearance of solutions that exhibit persistent oscillations,so-called oscillatory waves,which are(in general,measure-valued)solutions that emerge from Riemann data or slightly perturbed constant data chosen from the interior of the elliptic *** capture these solutions,usually a fine computational grid is *** this work,a version of the multiresolution method applied to a WENo scheme for systems of conservation laws is proposed as a simulation tool for the efficient computation of solutions of oscillatory wave *** hyperbolic-elliptic 2×2 systems of conservation laws considered are a prototype system for three-phase flow in porous media and a system modeling the separation of a heavy-buoyant bidisperse *** the latter case,varying one scalar parameter produces elliptic regions of different shapes and numbers of points of tangency with the borders of the phase space,giving rise to different kinds of oscillation waves.

关键词： Hyperbolic-elliptic system conservation law oscillation wave numerical simulation multiresolution method sedimentation model

Left-Handed Students and Clinical Practice in Dentistry: Adaptations, Difficulties and Realities Experienced in the Academic Environment

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open Journal of Preventive Medicine 2016年第11期6卷 247-259页

作者： Elisa Marianna Abreu Silva Itanielly Dantas Silveira Cruz Iris do Céu Clara costa Kenio costa de Lima Georgia costa de Araújo Souza Maria alice Pimentel fuscella fábia Barbosa de Andrade odontology Department Federal University of Rio Grande do Norte Natal Brazil State University of Rio Grande do Norte Caicó Brazil odontology Course Potiguar Faculty Natal Brazil faculty of Health Sciences of Trairi Federal University of Rio Grande do Norte Santa Cruz Brazil

objectives: To verify the existence of difficulties throughout the course of dentistry clinical practices, identify musculoskeletal pain, and evaluate frequency and intensity of pain/discomfort (if existent) in different regions of the body, experienced by left- handed students in comparison to right-handed students of the odontology courses of the state of Rio Grande do Norte (Northeast Brazil). Methods: A general questionnaire was applied to identify left-handed students in a population of 750 students, enrolled in clinical courses. An adaptation of the Grad-Corllet Diagram and a specific questionnaire on clinical practices were applied to the selected students. Descriptive statistics was utilized to analyze data of the specific questionnaire, and Mann-Whitney statistics, chi-square or fisher’s Exact tests (with a 5% significance level) were utilized for the Grad-Corllet Diagram, searching for an association be- tween discomfort/pain in different body regions and manual laterality. Results: All students presented higher percentage of pain in the lumbar and neck/cervical re- gions. However, left-handed students presented higher values, with statistical signifi- cance levels of p = 0.041 for lower back, p = 0.002 for neck and p = 0.003 for cervical region. Conclusions: The majority of left-handed students classified “moderate” the difficulty of working with equipment designed for right-handers. There was high frequency of musculoskeletal pain/discomfort, with relevant statistical results for left- handed students regarding intensity. It is suggested that the participating institutions evaluate the adoption of inclusion politics, re-adapt the infrastructure to include equipment designed for left-handers, and finally provide adequate work conditions for all students.

关键词： Left-Hander odontology Undergraduate Academic orientation Musculoskeletal Pain