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Rapid on-site evaluation of endoscopic-ultrasound-guided fine-needle aspiration diagnosis of pancreatic masses

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World journal of Gastroenterology 2014年第28期20卷 9451-9457页

作者： julio iglesias-Garcia j.se Lario-Noia Ihab Abdulkader j Enrique Domínguez-Muoz Department of Gastroenterology and Hepatology Foundation for Research in Digestive DiseasesUniversity Hospital of Santiago de Compostela Department of Pathology University Hospital of Santiago de Compostela

Endoscopic ultrasound (EUS) has become an essential tool for the study of pancreatic diseases. Specifically, EUS plays a pivotal role evaluating patients with a known or suspected pancreatic mass. In this setting, differential diagnosis remains a clinical challenge. EUS-guided fine-needle aspiration (FNA) and fine-needle biopsy (FNB) have been proven to be safe and useful tools in this setting. EUS-guided FNA and FNB, by obtaining cytological and/or histological samples, are able to diagnose pancreatic lesions with high sensitivity and specificity. In this context, several methodological features, trying to increase the diagnostic yield of EUS-guided FNA and FNB, have been evaluated. In this review, we focus on the role of rapid on-site evaluation (ROse). From data reported in the literature, ROse may increase diagnostic yield of EUS-FNA specimens by 10%-30%, and thus, diagnostic accuracy. However, we should point out that many recent studies have reported adequacy rates of > 90% without ROse, indicating that, perhaps, at high-volume centers, ROse may not be indispensable to achieve excellent results. The use of ROse can be considered important during the learning curve of EUS-FNA, and also in hospital with diagnostic accuracy rates < 90%.

关键词： Endoscopic-ultrasound-guided fine-needle aspiration Rapid on-site evaluation Solid pancreatic tumors Diagnostic accuracy

Direct ink writing of polycaprolactone/polyethylene oxide based 3D constructs

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Progress in Natural Science:Materials International 2021年第2期31卷 180-191页

作者： Bin Zhang se Hun Chung Susan Barker Duncan Craig Roger j.Narayan jie Huang Department of Mechanical Engineering University College London Medway School of Pharmacy Universities of Greenwich and Kent School of Pharmacy University College London joint Department of Biomedical Engineering University of North Carolina and North Carolina State University

There has been increasing interest over recent years in the application of three-dimensional(3 D) printing technologies in the biomedical field. One such method is Direct Ink Writing(DIW); this approach has the potential advantage of allowing room-temperature deposition of materials, presented as an ink, to build complex architectures. DIW offers the ability to process biomaterials containing temperature-sensitive components. Due to the fabrication principles of DIW, there are specific rheological requirements that the ink must exhibit for the 3 D construction. For this reason, hydrogel-based liquid feed stocks have been the focal point of ink development. As a consequence, studies based on inks comprising hydrophobic biomaterials, which are insoluble in water and hence unsuited to the hydrogel approach, have been *** this study, we investigate novel inks that utilize polycaprolactone(PCL), a hydrophobic polymer, as the primary constituent by dissolving the polymer in solvent systems based on dichloromethane(DCM) and acetone(ACE). Moreover, polyethylene oxide(PEO) was incorporated into the PCL systems in order to extend the range of hydrophilicity of the systems. The rheological properties of the inks were investigated as a function of polymer composition and solvent system. Woodpile constructs of PCL and PCL/PEO were fabricated using DIW method and were assessed by a series of material characterisation. The type of solvent system had a noticeable impact on the ink rheology, which ultimately affected the surface properties. The incorporation of PEO particularly enhanced the roughness and wettability of the constructs. Our results support the use of DIW as a new means to process hydrophobic polymers for biomedical applications.

关键词： Direct ink writing Polycaprolactone Polyethylene oxide Ink rheology Material characterisation 3D construct

Administration of soluble activin receptor 2B increases bone and muscle mass in a mouse model of osteogenesis imperfecta

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Bone Research 2015年第1期3卷 40-45页

作者： Douglas j DiGirolamo Vandana Singhal Xiaoli Chang se-jin Lee Emily L Germain-Lee Department of Orthopaedic Surgery Johns Hopkins University School of Medicine Bone & Osteogenesis Imperfecta Department Kennedy Krieger Institute Department of Molecular Biology and Genetics Johns Hopkins University School of Medicine Department of Pediatrics Johns Hopkins University School of Medicine

Osteogenesis imperfecta（OI） comprises a group of heritable connective tissue disorders generally defined by recurrent fractures, low bone mass, short stature and skeletal fragility. Beyond the skeletal complications of OI,many patients also report intolerance to physical activity, fatigue and muscle weakness. Indeed, recent studies have demonstrated that skeletal muscle is also negatively affected by OI, both directly and indirectly. Given the well-established interdependence of bone and skeletal muscle in both physiology and pathophysiology and the observations of skeletal muscle pathology in patients with OI, we investigated the therapeutic potential of simultaneous anabolic targeting of both bone and skeletal muscle using a soluble activin receptor 2B（ACVR2B） in a mouse model of type Ⅲ OI（oim）. Treatment of 12-week-old oim mice with ACVR2 B for 4 weeks resulted in significant increases in both bone and muscle that were similar to those observed in healthy,wild-type littermates. This proof of concept study provides encouraging evidence for a holistic approach to treating the deleterious consequences of OI in the musculoskeletal system.

关键词： bone Administration of soluble activin receptor 2B increases bone and muscle mass in a mouse model of osteogenesis imperfecta

Pathophysiological mechanisms underlying gastrointestinal symptoms in patients with COVID-19

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World journal of Gastroenterology 2021年第19期27卷 2341-2352页

作者： Byungchang jin Rajan Singh se Eun Ha Hannah Zogg Paul j Park seungil Ro Department of Physiology and Cell Biology University of Nevada School of MedicineRenoNV 89557United States Department of Medicine Renown HealthRenoNV 89557United States

Gastrointestinal(GI)symptoms,such as diarrhea,abdominal pain,vomiting,and anorexia,are frequently observed in patients with coronavirus disease 2019(COVID-19).However,the pathophysiological mechanisms connecting these GI symptoms to severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infections remain *** studies indicate that the entry of SARS-CoV-2 into intestinal cells leads to downregulation of angiotensin converting enzyme 2(ACE2)receptors resulting in impaired barrier *** intestinal ACE2 functions as a chaperone for the amino acid transporter B0AT1,the B0AT1/ACE2 complex within the intestinal epithelium acts as a regulator of gut microbiota composition and *** to the B0AT1/ACE2 complex lead to microbial dysbiosis through increased local and systemic immune *** studies have also suggested that altered serotonin metabolism may be the underlying cause of GI disorders involving *** findings of elevated plasma serotonin levels and high fecal calprotectin in COVID-19 patients with diarrhea indicate that the viral infection evokes a systemic inflammatory response that specifically involves the ***,the elevated proinflammatory cytokines correlate with elevated serotonin and fecal calprotectin levels further supporting the evidence of GI inflammation,a hallmark of functional GI ***,the finding that rectal swabs of COVID-19 patients remain positive for SARS-CoV-2 even after the nasopharynx clears the virus,suggests that viral replication and shedding from the GI tract may be more robust than that of the respiratory tract,further indicating fecal-oral transmission as another important route of viral *** review summarized the evidence for pathophysiological mechanisms(impaired barrier function,gut inflammation,altered serotonin metabolism and gut microbiota dysbiosis)underlying the GI symptoms in patients with COVID-19.

关键词： COVID-19 Gastrointestinal symptoms Gut microbiota dysbiosis Impaired barrier function serotonin Angiotensin converting enzyme 2 receptor

Dual Zariski Spaces of Modules

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Algebra Colloquium 2023年第4期30卷 569-584页

作者： seçilÇeken Department of Mathematics Trakya UniversityEdirneTurkey

Let R be a commutative ring with identity,M be an R-module,L(M)denote the set of all submodules of M and g■(M)\{OM}.For any submodule N of M,we set gV^(d)(N)={K∈g:K■N}and gζ^(d)(M)=(GV^(d)(N):N■L(M)).Consider χ■L(R)\{R},where L(R)is the set of all ideals of *** set χV(I)=(j∈x:I■j.and χζ(R)={xV(I):I■L(R)}for any ideal I of *** this paper,we investigate when,for arbitrary χ and g as above,χζ(R)and gζ^(d)(M)form a topology and a semimodule,*** investigate the structure of gζ^(d)(M)in the case that it is a semimodule.

关键词： dual Zariski semimodule χ-Zariski semiring ·-coprime submodule subtractive subspace

Interaction of silver nanoparticles with mediterranean agricultural soils: Lab-controlled adsorption and desorption studies

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journal of Environmental Sciences 2019年第9期31卷 205-216页

作者： Laura Torrent Eva Margui Ignasi Queralt Manuela Hidalgo Monica iglesias Department of Chemistry University of Girona C/M. Aurelia Capmany 69 17003 Girona Spain Institute of Environmental Assessment and Water Research (IDAEA-CSIC) C. Jordi Girona 28-26 08034 Barcelona Spain

The production of silver nanoparticles(AgNPs) has increased tremendously during recent years due to their antibacterial and physicochemical properties. As a consequence, these particles are released inevitably into the environment, with soil being the main sink of disposal. Soil interactions have an effect on AgNP mobility, transport and bioavailability. To understand AgNP adsorption processes, lab-controlled kinetic studies were *** tests performed with five different Mediterranean agricultural soils showed that cation exchange capacity and electrical conductivity are the main parameters controlling the adsorption processes. The adsorption kinetics of different sized(40, 75, 100 and 200 nm)and coated(citrate, polyvinylpyrrolidone and polyethyleneglycol(PEG)) AgNPs indicated that these nanoparticle properties have also an effect on the adsorption *** assess the mobility and bioavailability of AgNPs and to determine if their form is maintained during adsorption/desorption processes, loaded soils were submitted to leaching tests three weeks after batch adsorption studies. The DIN 38414-S4 extraction method indicated that AgNPs were strongly retained on soils, and single-particle inductively coupled plasma mass spectrometry confirmed that silver particles maintained their nanoform, except for 100 nm PEG-AgNPs and 40 nm citrate-coated AgNPs. The DTPA(diethylenetriaminepentaacetic acid) leaching test was more effective in extracting silver,but there was no presence of AgNPs in almost all of these leachates.

关键词： Silver nanoparticles Agricultural soils Sorption kinetics Leaching tests Single-particle inductively coupled plasma mass spectrometry

Advanced 4D-bioprinting technologies for brain tissue modeling and study

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International journal of Smart and Nano Materials 2019年第3期10卷 177-204页

作者： Timothy j.Esworthy Shida Miao se-jun Lee Xuan Zhou Haitao Cui Yi Y.Zuo Lijie Grace Zhang Department of Mechanical and Aerospace Engineering The George Washington UniversityWashingtonDCUSA Department of Mechanical Engineering University of Hawaii at ManoaHonoluluHIUSA Department of Medicine The George Washington UniversityWashingtonDCUSA Department of Biomedical Engineering The George Washington UniversityWashingtonDCUSA Department of Electrical and Computer Engineering The George Washington UniversityWashingtonDCUSA

Although the process by which the cortical tissues of the brain fold has been the subject of considerable study and debate over the past few decades,a single mechanistic description of the phenomenon has yet to be fully ***,two competing explanations of cortical folding have arisen in recent years;known as the axonal tension and the differential tangential expansion *** the present review,these two models are introduced by analyzing the computational,theoretical,materials-based,and cell studies which have yielded *** Four-dimensional bioprinting is presented as a powerful technology which can not only be used to test both models of cortical folding de novo,but can also be used to explore the reciprocal effects that folding associated mechanical stresses may have on neural ***,the fabrication of‘smart’tissue models which can accurately simulate the in vivo folding process and recapitulate physiologically relevant stresses are *** also provide a general description of both cortical neurobiology as well as the cellular basis of cortical *** discussion also entails an overview of both 3D and 4D bioprinting technologies,as well as a brief commentary on recent advancements in printed central nervous system tissue engineering.

关键词： 4D bioprinting smart materials brain cortical folding gyrification

Theoretical insights of the pharmaceutical compound fluoxetine in water:Role in direct photolysis and indirect photolysis by free radicals

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journal of Environmental Sciences 2024年第8期142卷 269-278页

作者： Ying Lu se Wang Yifan Shen School of Environmental Science and Engineering Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologyJiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution ControlNanjing University of Information Science and TechnologyNanjing 210044China

The frequent detection of pharmaceutical compounds in the environment has led to a growing awareness,which may pose a major threat to the aquatic *** this study,photodegradation(direct and indirect photolysis)of two different dissociation states of fluoxetine(FLU)was investigated in water,mainly including the determination of photolytic transition states and products,and the mechanisms of indirect photodegradation with·OH,CO_(3)^(*-)and NO_(3)^(*).The main direct photolysis pathways are defluorination and C–C bond *** addition,the indirect photodegradation of FLU in water is mainly through the reactions with·OH and NO_(3)^(*),and the photodegradation reaction with CO_(3)^(*-)is relatively difficult to occur in the water *** results provide a theoretical basis for understanding the phototransformation process of FLU in the water environment and assessing its potential risk.

关键词： Fluoxetine Photochemical mechanism Direct photolysis Free radical reaction DFT

A novel near-infrared light responsive 4D printed nanoarchitecture with dynamically and remotely controllable transformation

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Nano Research 2019年第6期12卷 1381-1388页

作者： Haitao Cui Shida Miao Timothy Esworthy se-jun Lee Xuan Zhou Sung Yun Hann Thomas j.Webster Brent T.Harris Lijie Grace Zhang Department of Mechanical and Aerospace Engineering The George Washington UniversityWashingtonDC 20052USA Department of Chemical Engineering Northeastern UniversityBostonMA 02115USA Department of Neurology and Pathology Georgetown UniversityWashingtonDC 20007USA Departments of Electrical and Computer Engineering The George Washington UniversityWashingtonDC 20052USA Department of Biomedical Engineering The George Washington UniversityWashingtonDC 20052USA Department of Medicine The George Washington UniversityWashingtonDC 20052USA

Four-dimensional (4D) printing is an emerging and highly innovative additive manufacturing process by which to fabricate pre-designed,self-assembly structures with the ability to transform over ***,one of the critical challenges of 4D printing is the lack of advanced 4D printing systems that not only meet all the essential requirements of shape change but also possess smart,dynamic capabilities to spatiotemporally and instantly control the shape-transformation ***,we present a facile 4D printing platform which incorporates nanomaterials into the conventional stimuli-responsive polymer,allowing the 4D printed object to achieve a dynamic and remote controlled,on-time and position shape transformation.A proof-of-concept 4D printed brain model was created using near-infrared light (NIR) responsive nanocomposite to evaluate the capacity for controllable 4D transformation,and the feasibility of photothermal stimulation for modulating neural stem cell *** novel 4D printing strategy can not only be used to create dynamic 3D patterned biological structures that can spatiotemporally control their shapes or behaviors of transformation under a human benign stimulus (NIR),but can also provide a potential method for building complex self-morphing objects for widespread applications.

关键词： near-infrared light responsive four-dimensional (4D) printing dynamically and remotely controllable graphene brain neural stem cell