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Pollen Tube Growth: a Delicate Equilibrium Between Secretory and Endocytic Pathways

Journal of Integrative Plant Biology 2009年第8期51卷 727-739页

作者： Alessandra Moscatelli Aurora irene Idilli Dipartimento di Biologia L. Gorini Università degli Studi di MilanoVia Celoria 26 20133 Milano Italy

Although pollen tube growth is a prerequisite for higher plant fertilization and seed production, the processes leading to pollen tube emission and elongation are crucial for understanding the basic mechanisms of tip growth. It was generally accepted that pollen tube elongation occurs by accumulation and fusion of Golgi-derived secretory vesicles （SVs） in the apical region, or clear zone, where they were thought to fuse with a restricted area of the apical plasma membrane （PM）, defining the apical growth domain. Fusion of SVs at the tip reverses outside cell wall material and provides new segments of PM. However, electron microscopy studies have clearly shown that the PM incorporated at the tip greatly exceeds elongation and a mechanism of PM retrieval was already postulated in the mid-nineteenth century. Recent studies on endocytosis during pollen tube growth showed that different endocytic pathways occurred in distinct zones of the tube, including the apex, and led to a new hypothesis to explain vesicle accumulation at the tip; namely, that endocytic vesicles contribute substantially to V-shaped vesicle accumulation in addition to SVs and that exocytosis does not involve the entire apical domain. New insights suggested the intriguing hypothesis that modulation between exo- and endocytosis in the apex contributes to maintain PM polarity in terms of lipid/protein composition and showed distinct degradation pathways that could have different functions in the physiology of the cell. Pollen tube growth in vivo is closely regulated by interaction with style molecules. The study of endocytosis and membrane recycling in pollen tubes opens new perspectives to studying pollen tube-style interactions in vivo.

关键词： endocytosis exocytosis membrane recycling polarized growth pollen tube

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Late polymicrobial transjugular intrahepatic portosystemic shunt infection in a liver transplant patient:A case report

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World Journal of Hepatology 2022年第4期14卷 846-853页

作者： irene De La Caridad Perez Ziv J Haskal John I Hogan Curtis K Argo Department of Medicine University of Virginia Medical CenterCharlottesvilleVA 22903United States Department of Radiology and Medical Imaging Division of Vascular and Interventional RadiologyUniversity of Virginia Medical CenterCharlottesvilleVA 22903United States Department of Medicine Division of Infectious Diseases and International HealthUniversity of Virginia Medical CenterCharlottesvilleVA 22903United States Department of Medicine Division of Gastroenterology and HepatologyUniversity of Virginia Medical CenterCharlottesvilleVA 22903United States

BACKGROUND Infection of a transjugular intrahepatic portosystemic shunt(TIPS)stent is a rare and serious complication that most commonly occurs during TIPS creation and *** typically present with recurrent bacteremia due to shunt occlusion or *** date there are approximately 58 cases *** present a patient diagnosed with late polymicrobial TIPS infection five years following TIPS *** SUMMARY A 63-year-old female status-post liver transplant with recurrent cirrhosis and portal hypertension presented with sepsis and recurrent extended-spectrum betalactamase Escherichia coli *** tomography of the abdomen revealed an occluded TIPS with thrombus extension into the distal right portal vein,and focal thickening of the cecum and ascending *** revealed patchy ulcers in these areas with histopathology demonstrating ulcerated colonic mucosa with fibrinopurulent *** thrombectomy and revision revealed infected-appearing *** initially cleared her infection with antibacterial therapy and TIPS revision;however,soon after,she developed Enterobacter cloacae bacteremia and Candida glabrata and *** fungemia with recurrent TIPS *** remained on antifungal therapy indefinitely and later developed vancomycin-resistant Enterococcus faecium with recurrent TIPS *** option of liver re-transplant for removal of the infected TIPS was not offered given her critical illness and complex shunt *** patient became intolerant to linezolid and elected hospice *** Clinicians should be aware that TIPS superinfection may occur as long as five years following TIPS creation in an immunocompromised patient.

关键词： Transjugular intrahepatic portosystemic shunt Endotipsitis Colitis Liver cirrhosis Liver transplantation Case report

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Efficient Algorithms for Approximating Particular Solutions of Elliptic Equations Using Chebyshev Polynomials

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Communications in Computational Physics 2007年第3期2卷 501-521页

作者： Andreas Karageorghis irene Kyza Department of Mathematics and Statistics University of CyprusP.O.Box 205371678 NicosiaCyprus Department of Mathematics University of CreteP.O.Box 2208GR-71409 HeraklionGreece.

In this paper,we propose efficient algorithms for approximating particular solutions of second and fourth order elliptic *** approximation of the particular solution by a truncated series of Chebyshev polynomials and the satisfaction of the differential equation lead to upper triangular block systems,each block being an upper triangular *** systems can be solved efficiently by standard *** numerical examples are presented for each case.

关键词： Chebyshev polynomials Poisson equation biharmonic equation method of particular solutions.

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HLA-G and single nucleotide polymorphism(SNP)associations with cancer in African populations:Implications in personal medicine

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Genes & Diseases 2022年第5期9卷 1220-1233页

作者： Ismael Chatita Adolf Amany Almars Nazima Dharsee Teddy Mselle Gokce Akan irene Jeremiah Nguma Abdolrahman S.Nateri Fatmahan Atalar Mbeya College of Health and Allied Sciences University of Dar es SalaamMbeyaP.O Box 608Tanzania Cancer Genetics&Stem Cell Group BioDiscovery InstituteDivision of Cancer and Stem CellsSchool of MedicineUniversity of NottinghamNottinghamNG72UHUK Ocean Road Cancer Institute Department of OncologyDar es SalaamP.O Box 3592Tanzania Muhimbili University of Health and Allied Sciences MUHAS Genetic LaboratoryDepartment of BiochemistryDar es SalaamP.O Box 65001Tanzania Clinical Oncology Department Mbeya Zonal Referral Hospital(MZRH)Mbeya P.O Box 419Tanzania Child Health Institute Department of Rare DiseasesIstanbul UniversityIstanbul 34093Turkey

The immune system plays an important role in protecting the body against *** cancer immunoediting,the immune system can recognize and keep checking the tumor cells by down-expression of some self-molecules or by increasing expression of some novel ***,the microenvironment created in the course of cancer development hampers the immune ability to recognize and destroy the transforming *** Leukocyte Antigen G(HLA-G)is emerging as immune checkpoint molecule produced more by cancer cells to weaken the immune response against ***-G is a non-classical HLA class I molecule which is normally expressed in immune privileged tissues as a soluble or membrane-bound ***-G locus is highly polymorphic in the non-coding 3′untranslated region(UTR)and in the 5′upstream regulatory region(5′URR).HLA-G expression is controlled by polymorphisms located in these regions,and several association studies between these polymorphic sites and disease predisposition,response to therapy,and/or HLA-G protein expression have been *** polymorphisms are demonstrated to modulate its expression and this is increasingly finding more significance in cancer *** review focuses on the relevance of the HLA-G gene and its polymorphisms in cancer *** highlight population genetics of HLA-G as evidence to espouse the need and importance of exploring potential utility of HLA-G in cancer diagnosis,prognosis and immunotherapy in the currently understudied African population.

关键词： African population Cancer HLA-G Immune system checkpoints MHC Single nucleotide polymorphism

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Retinal and Choroidal Alterations in Migraine Patients Compared to Normal Healthy Controls

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Journal of Behavioral and Brain Science 2023年第10期13卷 185-197页

作者： Miriam L. Conway irene Ctori Department of Optometry and Visual Science City University of London London UK

Purpose: Migraine is an incapacitating neurovascular disorder that primarily affects the working-age population. Researchers have postulated that the transient vascular alterations during each migraine attack lead to ischemic damage in the eye which can be measured via optical coherence tomography. Methods: We recruited 29 volunteers: 13 migraineurs (mean age 28 ± 8.8 years;12 female and 1 male) and 16 age-matched controls (mean age 26.6 ± 6.9;9 female and 7 male). All individuals underwent a detailed ophthalmic examination by a qualified optometrist and a Migraine Disability Assessment. The investigators were blind to the migraine diagnosis. Retinal Nerve Fiber Layer (RNFL) thickness, Retinal Thickness (RT), Ganglion Cell Complex (GCL), ranging from the inner-limiting membrane to the inner plexiform layer, and Choroidal Thickness (CT) were measured using the 3D OCT-1Maestro, Topcon, a Spectral Domain OCT (SD-OCT) device. Results: In the migraine population average RNFL was lower for several parameters. However, results did not reach statistical significance. A significant decrease in the right eye inferior parafoveal ganglion cell layer in the migraine group of patients (mean = 25.15, SD = 4.08) compared to normal healthy controls (mean = 28.81, SD = 4.85;t = (27) = 2.17, p = 0.039) was documented. No other ganglion cell layer or choroidal thickness reached significance. No significant relationship between ocular thickness parameters and MIDAS score, parameters and either MIDAS score or frequency of headaches was found. Conclusion: A significant decrease in the right inferior parafoveal ganglion cell layer for migraine patients was reported. All other parameters did not reach significance. .

关键词： Retinal Choroidal Migraine

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Serum biomarkers for the differentiation of autoimmune pancreatitis from pancreatic ductal adenocarcinoma

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World Journal of Gastrointestinal Oncology 2023年第2期15卷 268-275页

作者： Octavio Caba Carmelo Diéguez-Castillo Joaquina Martínez-Galán irene González-Cebrián Cristina Jiménez-Luna Institute of Biopathology and Regenerative Medicine(IBIMER) University of GranadaGranada 18016Spain Biosanitary Institute of Granada(ibs.GRANADA) 18014 GranadaSpain Department of Gastroenterology San Cecilio University HospitalGranada 18016Spain Department of Medical Oncology Virgen de las Nieves University HospitalGranada 18014Spain.Biosanitary Institute of Granada(ibs.GRANADA)18014 GranadaSpain Department of Digestive Cancer San Cecilio University HospitalGranada 18016Spain

Autoimmune pancreatitis(AIP),a chronic inflammation caused by the immune system attacking the pancreas,usually presents imaging and clinical features that overlap with those of pancreatic ductal adenocarcinoma(PDAC).Serum biomarkers,substances that quantitatively change in sera during disease development,are a promising non-invasive tool with high utility for differentiating between these *** this way,the presence of AIP is currently suspected when serum concentrations of immunoglobulin G4(IgG4)antibody are ***,this approach has some ***,IgG4 antibody concentrations are also elevated in sera from some patients with *** review focuses on the most recent and relevant serum biomarkers proposed to differentiate between AIP and PDAC,evaluating the usefulness of immunoglobulins,autoantibodies,chemokines,and *** proposed serum biomarkers have proven useful,although most studies had a small sample size,did not examine their presence in patients with PDAC,or did not test them in *** addition,current evidence suggests that a single serum biomarker is unlikely to accurately differentiate these diseases and that a set of biomarkers will be needed to achieve adequate specificity and sensitivity,either alone or in combination with clinical data and/or radiological images.

关键词： Autoimmune pancreatitis Pancreatic ductal adenocarcinoma Serum Biomarkers Differentiation

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The Effect of Gum Acacia on Post-Prandial Glucose and Insulin Levels in Healthy Subjects

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Food and Nutrition Sciences 2022年第4期13卷 424-438页

作者： Udo Bongartz Constantin Erlenbeck irene Wohlfahrt analyze & realize GmbH Berlin Germany

This double-blind, controlled, randomized, three-way cross-over study evaluates the effect of 40 g (D1 group) and 20 g (D2 group) of acacia gum (AG) versus no treatment (NT group) on post-prandial glucose (PPG) levels in normal-weight and overweight subjects. Additionally, post-prandial insulin (PPI) levels as well as the safety and tolerability of gum acacia were assessed. 35 healthy subjects aged 25 - 60 years, body mass index 18.5 kg/m2 - 29.9 kg/m2, received one treatment of 20 g, 40 g, or 0 g of AG each. Glucose and insulin values were determined at -15 min and prior to the intake (time “0”) as well as 15, 30, 45, 60, 90 120, and 180 min after the “0 min” blood draw. The mean PPG levels were lower (34% in D1 group, p = 0.003;35% in D2 group, p = 0.005) than in the NT group. PPI concentration was statistically significantly lower at all time points except baseline in both treatment groups compared to NT groups. Global benefit and tolerability were rated as “very good” or “good” by 100% of subjects in the treatment groups. This study provides robust evidence of the significant benefits of AG consumption on PPG and PPI levels in healthy subjects. Moreover, very good tolerability was demonstrated.

关键词： Acacia Gum Post-Prandial Glucose Post-Prandial Insulin Glycemic Response Control

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Hormone abuse in sports： the antidoping perspective

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Asian Journal of Andrology 2008年第3期10卷 391-402页

作者： Osquel Barroso irene Mazzoni Olivier Rabin Science Department World Anti-Doping Agency （WADA） Montreal Quebec H4Z 1B7 Canada

Since ancient times, unethical athletes have attempted to gain an unfair competitive advantage through the use of doping substances. A list of doping substances and methods banned in sports is published yearly by the World AntiDoping Agency （WADA）. A substance or method might be included in the List if it fulfills at least two of the following criteria： enhances sports performance; represents a risk to the athlete＇s health; or violates the spirit of sports. This list, constantly updated to reflect new developments in the pharmaceutical industry as well as doping trends, enumerates the drug types and methods prohibited in and out of competition. Among the substances included are steroidal and peptide hormones and their modulators, stimulants, glucocorticosteroids, β2-agonists, diuretics and masking agents, narcotics, and cannabinoids. Blood doping, tampering, infusions, and gene doping are examples of prohibited methods indicated on the List. From all these, hormones constitute by far the highest number of adverse analytical findings reported by antidoping laboratories. Although to date most are due to anabolic steroids, the advent of molecular biology techniques has made recombinant peptide hormones readily available. These substances are gradually changing the landscape of doping trends. Peptide hormones like erythropoietin （EPO）, human growth hormone （hGH）, insulin, and insulin-like growth factor Ⅰ （IGF-Ⅰ） are presumed to be widely abused for performance enhancement. Furthermore, as there is a paucity of techniques suitable for their detection, peptide hormones are all the more attractive to dishonest athletes. This article will overview the use of hormones as doping substances in sports, focusing mainly on peptide hormones as they represent a pressing challenge to the current fight against doping. Hormones and hormones modulators being developed by the pharmaceutical industry, which could emerge as new doping substances, are also discussed.

关键词： World Anti-Doping Agency doping hormone sport

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Interface-facilitated stable plasticity in ultra-fine layered FeAl/FeAl_(2) micro-pillar at high temperature

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Journal of Materials Science & Technology 2021年第14期73卷 61-65页

作者： Lulu Li irene J.Beyerlein Weizhong Han Center for Advancing Materials Performance from the Nanoscale State Key Laboratory for Mechanical Behavior of MaterialsXi’an Jiaotong UniversityXi'an 710049China Department of Mechanical Engineering Materials DepartmentUniversity of CaliforniaSanta Barbara.CA.93106-5070USA

Fe-Al compounds possess a combination of high strength and corrosion resistance at high ***,increasing Al content to make them lighter results in ***,we investigate the high-temperature behavior of a novel,lightweight,ultra-fine-layered FeAl/FeAl_(2) *** report a transition from unstable to stable plasticity at 450℃.Below 450℃,deformation is dominated by localized shear deformation within the soft FeAl layers,while above 450℃,it proceeds by co-deformation between Fe Al and the brittle FeAl_(2) *** show that co-deformation is associated with the temperature at which the interface converts from sliding to sourcing dislocations for Fe Al_(2).

关键词： Fe-Al alloy Compression High-temperature Interface Dislocation

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A Complex Systems Science Perspective on Wireless Networks

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Journal of Systems Science & Complexity 2016年第4期29卷 1034-1056页

作者： MACALUSO irene GALIOTTO Carlo MARCHETTI Nicola DOYLE Linda CTVR Telecommunications Research Center Trinity College Dublin

The paper targets a future world where all wireless networks are self-organising entities and in which the predominant mode of spectrum access is dynamic. The paper explores whether the behaviour of a collection of autonomous self-organising wireless systems can be treated as a complex system and whether complex systems science can shed light on the design and deployment of these networks. The authors focus on networks that self-organise from a frequency perspective to understand the behaviour of a collection of wireless self-organising nodes. Each autonomous network is modelled as a cell in a lattice and follows a simple set of self-organisation rules. Two scenarios are considered, one in which each cell is based on cellular automata and which provides an abstracted view of interference and a second in which each cell uses a self-organising technique which more accurately accounts for interference. The authors use excess entropy to measure complexity and in combination with entropy gain an understanding of the structure emerging in the lattice for the self-organising networks. The authors show that the self-organising systems presented here do exhibit complex behaviour. Finally,the authors look at the robustness of these complex systems and show that they are robust against changes in the environment.

关键词： Dynamic spectrum access excess entropy robustness self organising wireless networks.

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