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Synthesis of the C1–C13 fragment of eribulin mesylate has been accomplished. It features a highly stereoselective construction of a trans-dihydropyran framework using three key reactions: (1) Sharpless epoxidation, (2) regioselective ring opening, and (3) olefin metathesis.

Five types of amine functional polymer shells were formed on the surface of silica nanoparticles via vapor deposition polymerization and oxidation polymerization. Scanning electron microscopy, transmission electron microscopy, elemental analysis, and Fourier transform infrared spectroscopy have been used to characterize the resulting various types of amine functional polymers coated silica nanoparticles. Electron microscopy studies reveal that the thin polymer shell is successfully formed on the silica surface. The antibacterial performance of the prepared core/shell nanoparticles was investigated against both Gram-positive (Escherichia coli) and Gram-negative (Staphylococcus aureus) bacteria. The various amine functional polymers coated silica nanoparticles presented antibacterial activity against both bacteria. In contrast, silica/PPy core/shell nanoparticles had no bactericidal efficiency, because the amine group of PPy does not provide protonated nitrogen atoms which can kill the bacteria. The obtained results evidence that antimicrobial activity of amine functional polymers is influenced by the state of the amine groups than positively charged amino groups.

Ag-coated AgBr nanoparticles (Ag@AgBr) were fabricated via an aqueous, one-pot route. In this system, poly(vinyl alcohol) (PVA) acted as a stabilizer for the formation of nanoscale AgBr composites through interaction with Ag ions and their hydroxyl (–OH) groups. The mild reducing agent L-arginine was used for partial reduction of AgBr to form metallic Ag nanoparticles on the AgBr surface. The metallic Ag nanoparticles enhanced light absorption in the visible region due to surface plasmon resonance (SPR). The size of the synthesized nanoparticles was controlled by varying the reaction temperature, and was found to influence the light absorption of Ag@AgBr nanocomposites. The prepared nano-photocatalysts exhibited excellent photocatalytic activities under both visible light and direct sunlight.

Syndecan-4 (heparan sulfate proteoglycan), biologically important in cell-to-cell interactions and tumor suppression, was studied through mutation of the GXXXG motif of its transmembrane domain (Syd4-TM), a motif which governs dimerization. The expression and purification of the mutant (mSyd4-TM) were optimized here to assess the function of the GXXXG motif in the dimerization of Syd4-TM. mSyd4-TM was obtained in M9 minimal media and its oligomerization was identified by SDS PAGE, Circular Dichroism (CD) spectroscopy, mass spectrometry and NMR spectroscopy. The mutant, unlike Syd4-TM, did not form dimers and was observed as monomers. The GXXXG motif of Syd-4TM was shown to be an important structural determinant of its dimerization.

Thin pDMAEMA shells were formed on the surface of silica nanoparticles via vapor deposition polymerization. Scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and elemental analysis have been used to characterize the resulting pDMAEMA-coated silica nanoparticles. Electron microscopy studies reveal that the thin polymer shell is formed on the silica surface. In this work, the particle diameter can be controlled (from ~19 to ~69 nm) by varying the size of silica core. The antibacterial performance of the core-shell nanoparticles was investigated against both Gram-positive (Escherichia coli) and Gram-negative (Staphylococcus aureus) bacteria. Importantly, the nano-sized pDMAEMA particles presented antibacterial activity against both bacteria without additional quaternization due to its enlarged surface area. Additionally, the bactericidal efficiency was enhanced by reducing the particle size, because the expanded surface area of the cationic polymer nanoparticles provides more active sites that can kill the bacteria.

E-mail: yakim@hufs.ac.krReceived December 27, 2012, Accepted January 21, 2013The syndecan family consists of four transmembrane heparan sulfate proteoglycans present in most cell typesand each syndecan shares a common structure containing a heparan sulfate modified extracellular domain, asingle transmembrane domain and a C-terminal cytoplasmic domain. To get a better understanding of themechanism and function of syndecan-4 which is one of the syndecan family, it is crucial to investigate its three-dimensional structure. Unfortunately, it is difficult to prepare the peptide because it is membrane-bound proteinthat transverses the lipid bilayer of the cell membrane. Here, we optimize the expression, purification, andcharacterization of transmembrane, cytoplasmic and short extracellular domains of syndecan4 (syndecan-4eTC). Syndecan-4 eTC was successfully obtained with high purity and yield from the M9 medium. Thestructural information of syndecan-4 eTC was investigated by MALDI-TOF mass (MS) spectrometry, circulardichroism (CD) spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. It was confirmed thatsyndecan-4 eTC had an α-helical multimeric structure like transmembrane domain of syndecan-4 (syndecan-4 TM) in membrane environments. Key Words : Syndecan, Syndecan-4, Transmembrane, NMR spectroscopy, Membrane proteinIntroductionThe syndecan family consists of heparan sulfate proteo-glycans, which are present on the surface of all cell types inhumans. This family regulates cell-to-cell interaction, celladhesion, cell proliferation and angiogenesis, as well ashelps in healing wounds by activation of growth factors.

Back contacts for Si solar cells made by Al evaporation and screen printing Al paste were studied by transmission electron microscopy. Si was found to diffuse into the Al during heating. Si diffusion formed vacancies in the Si wafer and Al could then penetrate the Si wafer in spiked formations. The Al spikes retracted during cooling, leaving a doped back surface field region. Copyright © 2012 John Wiley & Sons, Ltd.

Human melanocortin-4 receptor (hMC4R) among MC-Rs, expressed in the brain, is in charge of the control on energy homeostasis and food intake. The structure and function of human MC4R have been studied to understand their essential function and roles. To investigate the structure and function, it is necessary to prepare sufficient amounts of proteins. However, their expression and purification is demanding and time-consuming due to their innate insoluble and toxic properties. The heterozygous mutations of hMC4R, exchange of Asp 90 to Asn located in second transmembrane, cause severe obesity in human. To obtain purified hMC4R wt-TM2 for structural studies, it was first over-expressed and purified by fast protein liquid chromatography (FPLC) and then solution NMR studies were performed to get high-resolution spectra. In here, we established optimized purification scheme to get more purified target peptide.

Silver-nanoparticle-decorated polypyrrole (PPy) nanotubes (NTs) were fabricated by vapor deposition polymerization (VDP)-mediated hard-template method. Fe/Ag cations were attached on the wall of an AAO template by electrostatic interactions, and pyrrole monomers were polymerized by the reduction of Fe/Ag cations due to chemical oxidation polymerization. The Ag NPs/PPy NTs are applied as antimicrobial agents against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus. The antimicrobial results show that the antimicrobial performance of Ag NPs/PPy NTs increases with the increasing of the population of Ag NPs loaded on PPy NT. At 30% (wt/wt) Ag NPs/PPy NTs, the minimum inhibitory concentrations (MICs) were 10 and 200 μg/mL against Escherichia coli and Staphylococcus aureus, respectively. Open image in new window

Novel fluorescent polyacrylonitrile nanoparticles were synthesized by microemulsion polymerization and Schiff base modification. By further modification with europium, the polyacrylonitrile nanoparticles could be used as a highly sensitive and rapid sensor for Bacillus anthracis spore detection in aqueous solution. The europium-modified polyacrylonitrile nanoparticles were readily combined with dipicolinic acid as a unique biomarker of B. anthracis , leading to high fluorescence emission. These nanoparticles enabled ratiometric detection without instrument-specific calibration due to the internal fluorescence reference. Additionally, the europium-modified polyacrylonitrile nanoparticle sensors exhibited a remarkable limit of detection (10 pM) for dipicolinic acid and outstanding selectivity (160×) over aromatic ligands in aqueous solution. The ultrafine nanoparticle sensor showed a high capability for detecting anthrax due to the increased surface area-to-volume ratio and enhanced dispersibility.

China criticized North Korea's nuclear test in 2006, but Beijing refused to condemn Pyongyang's provocations in 2010. When will China punish North Korea's belligerence? The “Dual Threats Model” suggests that China responds only when Pyongyang's activities heighten the possibility of U.S. military response, and as long as Pyongyang remains stable.

Quaternary ammonium compounds have been considered as excellent antibacterial agents due to their effective biocidal activity, long term durability and environmentally friendly performance. In this work, 3-(trimethoxysilyl)-propyldimethyloctadecylammonium chloride as a quaternary ammonium silane was applied for the surface modification of silica nanoparticles. The quaternary ammonium silane provided silica surface with hydrophobicity and antibacterial properties. In addition, the glass surface which was coated with the surface modified silica nanoparticles presented bacterial growth inhibition activity. For comparison of bacterial growth resistance, hydrophobic silane (alkyl functionalized silane) modified silica nanoparticles and pristine silica nanoparticles were prepared. As a result of bacterial adhesion test, the quaternary ammonium functionalized silica nanoparticles exhibited the enhanced inhibition performance against growth of Gram-negative Escherichia coli (96.6%), Gram-positive Staphylococcus aureus (98.5%) and Deinococcus geothermalis (99.6%) compared to pristine silica nanoparticles. These bacteria resistances also were stronger than that of hydrophobically modified silica nanoparticles. It could be explained that the improved bacteria inhibition performance originated from the synergistic effect of hydrophobicity and antibacterial property of quaternary ammonium silane. Additionally, the antimicrobial efficacy of the fabricated nanoparticles increased with decreasing size of the nanoparticles.

Quantum effects have been incorporated in the analytic potential model for double-gate MOSFETs. From extensive solutions to the coupled Schrodinger and Poisson equations, threshold voltage shift and inversion layer capacitance are extracted as closed form functions of silicon thickness and inversion charge density. With these modifications, the compact model is shown to reproduce C-V and I-V curves of double-gate MOSFETs consistent with those obtained from those measured from experimental FinFET hardware.

This brief presents an analytical solution of the electrostatic potential for nanowire MOSFETs in the subthreshold region by solving Poisson's equation in two dimensions (2D) in both semiconductor and gate insulator regions under cylindrical coordinates. Combining the analytical solution with the current continuity equation, one can derive an expression for the subthreshold current, from which the important parameters for short-channel effects (SCEs), such as threshold voltage rolloff, drain-induced barrier lowering, and subthreshold slope degradation, are analytically extracted. The 2D analytical model for SCEs has been validated by the numerical simulation results.

A simple synthetic method has been developed for the fabrication of antimicrobial polyrhodanine nanotubes with silver nanoparticles. Rhodanine monomer first forms one-dimensional complexes with silver ions due to coordinative interactions and consecutively reduces the silver ions during chemical-oxidation polymerization. The polymerization procedure is analyzed by transmission electron microscopy and scanning electron microscopy in situ. The synthesized silver nanoparticles/polyrhodanine nanotubes are applied as an antimicrobial agent against Gram-negative bacteria, E. coli and Gram-positive bacteria, S. aureus. The antimicrobial tests demonstrate that the silver/polyrhodanine nanotubes have superior antimicrobial properties to silver nanoparticles and rhodanine monomer.

This paper reviews recent development on compact modeling of multiple-gate (MG) MOSFETs. Long-channel core models based on the analytical potential solutions of Poisson and current continuity equations for symmetric double-gate (DG) and surrounding-gate (SG) MOSFETs have been developed first. Highly accurate explicit solutions are subsequently developed to deal with the implicit algebraic equations of the models. By adding quantum mechanical effects and short-channel effects, as well as capacitance formulations, the core model for DG MOSFETs has been expanded into a full-blown compact model which has been calibrated to and validated by experimental FinFET hardware. With regard to the various other types of MG MOSFETs developed, the core models for DG and SG MOSFETs have been generalized to the less symmetric structures, including quadruple-gate (QG), triple-gate (TG), ?-gate, and ?-gate MOSFETs. Other research activities on multiple-gate MOSFETs are briefly summarized at the end.

Threshold voltage shift due to quantum confinement in surrounding gate MOSFETs with anisotropic effective mass is calculated from the solution of 2D Schrodinger equation in elliptic coordinates. The solutions are of the Mathieu function type. It is shown that for some intermediate range of radius in silicon, several subbands need be taken into account to obtain accurate threshold voltage shifts. However, for small radius, only the lowest subband need be considered, and even anisotropic effective mass can be replaced by reduced isotropic effective mass, for which Bessel function is sufficient.

In this paper, a unified analytic drain-current model is presented for various kinds of multiple-gate (MG) MOSFETs, including quadruple-gate (QG), triple-gate (TG), Pi-gate, and Omega-gate MOSFETs. The basis of the unified model lies in the analytic potential models previously developed for highly symmetric double-gate (DG) and surrounding-gate (SG) MOSFETs. A common characteristic for all MG MOSFETs is that the inversion charge in subthreshold is proportional to the silicon cross- sectional area (volume inversion), whereas the inversion charge above threshold is proportional to the gated perimeter of the silicon body. It is shown that the inversion charge in a QG MOSFET can be modeled by multiplying the inversion charge of SG MOSFET by a function that changes smoothly from unity in subthreshold to a factor larger than unity above threshold. Inasmuch as the inversion charge is expressed as a function of the gate voltage, the drain-current can be evaluated by using the Pao-Sah integral approach. Once the QG model is obtained, other TG, Pi-gate, and Omega-gate MOSFET models can be formulated as a linear combination of DG and QG MOSFETs. Numerical simulation results that validate the unified model are presented.

This work describes the synthesis of silver/polyrhodanine-composite-decorated silica nanoparticles and their antibacterial activity. Polymerization of polyrhodanine proceeded preferentially on the surface of the silica nanoparticles where Ag(+) ions were located. In addition, the embedded Ag(+) ions were reduced to form metallic Ag nanoparticles; consequently, silver/polyrhodanine-composite nanoparticles (approximately 7 nm in diameter) were formed on the surface of the silica nanoparticles. The resulting nanostructure was investigated using electron microscopy, Fourier-transform infrared spectroscopy, ultraviolet-visible spectroscopy, and X-ray photoelectron spectroscopy. The silver/polyrhodanine-nanocomposite-decorated silica nanoparticles exhibited excellent antimicrobial activity toward gram-negative Escherichia coli and gram-positive Staphylococcus aureus because of the antibacterial effects of the silver nanoparticles and the polyrhodanine. The silver/polyrhodanine-composite nanoparticles may therefore have potential for use as a long-term antibacterial agent.

A one pot and environmentally benign synthetic route for plasmonic photocatalytic Ag@AgCl nanoparticles in a PVA-dissolved aqueous solution system is presented. The synthesized AgCl has a cubic-shape and its edge length can be controlled from ~57 to ~170 nm by varying the reaction temperature. In this system, PVA was used as a stabilizer for the formation of Ag@AgCl nanoparticles through interaction with Ag(+) ions. After partial reduction with l-arginine, the metallic Ag is formed on the surface of the AgCl substrates and the contents of the metallic Ag mainly affect both the visible-light absorption properties and the plasmonic photocatalytic efficiency of the Ag@AgCl nanocomposites. A plausible growth mechanism of metallic silver during the reduction process is proposed. More importantly, it is verified that the size of the AgCl substrate affected the light absorption region of the Ag@AgCl nanocomposite.

Protection against bacterial infections is an important research field in modern society. Antimicrobial polymers have received considerable attention as next-generation biocides because they represent an ecologically friendly approach that does not promote resistance. In the last decade, many authors have reported the development of nano-sized antimicrobial polymers with enhanced bactericidal performance by increasing the active-area of biocides. This review presents several suitable methods of synthesis of antimicrobial polymer nanomaterials with various shapes, including a nanosphere and fibrous and tubular structures. We also discuss the antimicrobial mechanisms of these polymers. In addition, antimicrobial polymer thin films, which can inhibit bacterial adhesion, are introduced briefly with examples. Our aim is to present synthetic routes and formation mechanisms of various antimicrobial polymer nanostructures.

This paper describes the one-pot, aqueous synthesis of cationic polymer nanofibers with embedded silver nanoparticles. Poly[2-(tert-butylaminoethyl) methacrylate] (PTBAM) was used as a cationic polymer substrate to reinforce the antimicrobial activity of the embedded silver nanoparticles. Electron microscope analyses revealed that the as-synthesized nanofibers had diameters of approximately 40 nm and lengths up to about 10 μm. Additionally, silver nanoparticles of approximately 8 nm in diameter were finely embedded into the prepared nanofibers. The embedded silver nanoparticles had a lower tendency to agglomerate than colloidal silver nanoparticles of comparable size. In addition, the nanofibers with embedded silver nanoparticles exhibited excellent antibacterial performance against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus. Interestingly, the prepared nanofibers exhibited enhanced bactericidal performance compared with the silver-embedded poly(methyl methacrylate) (PMMA) nanofibers, presumably because of the antibacterial properties of the PTBAM substrate.

Novel ZnO/TiO(2) composite nanofibers were fabricated by an electrospinning method and showed excellent antimicrobial activity against gram-negative Escherichia coli and gram-positive Staphylococcus aureus under UV irradiation and in the absence of light.

Polyrhodanine-coated γ-Fe(2)O(3) nanoparticles, synthesized by one-step chemical oxidation polymerization, were applied to the process of removal of heavy metal ions from aqueous solution. Factors influencing the uptake of heavy metal ions such as solution pH, initial metal ion concentration, contact time, and species of metal ions were investigated systematically by batch experiments. The adsorption equilibrium study exhibited that the Hg(II) ion adsorption of polyrhodanine-coated magnetic nanoparticles followed a Freundlich isotherm model than a Langmuir model. The kinetic data of adsorption of Hg(II) ion on the synthesized adsorbents were best described by a pseudo-second-order equation, indicating their chemical adsorption. In addition, the synthesized nano-adsorbents can be repeatedly used with help of an external magnetic field due to their magnetic properties. This work demonstrates that the magnetic polyrhodanine nanoparticles can be considered as a potential recyclable adsorbent for hazardous metal ions from wastewater.

Polyrhodanine was immobilized onto the inner surface of anodic aluminum oxide (AAO) membrane via vapor deposition polymerization method. The polyrhodanine modified membrane was applied to remove heavy metal ions from aqueous solution because polyrhodanine could be coordinated with specific metal ions. Several parameters such as initial metal concentration, contact time and metal species were evaluated systematically for uptake efficiencies of the fabricated membrane under continuous flow condition. Adsorption isotherms of Hg(II) ion on the AAO-polyrhodanine membrane were analyzed with Langmuir and Freundlich isotherm models. The adsorption rate of Hg(II) ion on the membrane was obeyed by a pseudo-second order equation, indicating the chemical adsorption. The maximum removal capacity of Hg(II) ion onto the fabricated membrane was measured to be 4.2 mmol/g polymer. The AAO-polyrhodanine membrane had also remarkable uptake performance toward Ag(I) and Pb(II) ions. Furthermore, the polyrhodanine modified membrane could be recycled after recovery process. These results demonstrated that the polyrhodanine modified AAO membrane provided potential applications for removing the hazardous heavy metal ions from wastewater.

Novel polymer based photoluminescent nanoparticles were fabricated by ultra-sound induced emulsion polymerization and applied to bioimaging of human breast cancer SK-BR-3 cells after ethylenediamine treatment and conjugation with anti-ErbB2 antibody.

Novel biocidal polymer-functionalized TiO(2) nanoparticles were prepared by surface-initiated photopolymerization using titania as an initiator. Vinyl monomer mixtures of nontoxic secondary amine-containing biocidal 2-(tert-butylamino)ethyl methacrylate and antifouling ethylene glycol dimethacrylate were used for the antimicrobial polymer shell. It was shown that the synthesized TiO(2)/poly[2-(tert-butylamino)ethyl methacrylate-co-ethylene glycol dimethacrylate] core/shell nanoparticles had enhanced photocatalytic antibacterial properties compared to the pristine TiO(2) nanoparticles due to the combined antibacterial activities of light-driven anti-infective TiO(2) core and biocidal polymer shell. In the dark condition, the TiO(2)/biocidal polymer nanoparticles exhibited high antimicrobial efficiency (95.7%) against gram-positive S. aureus. Furthermore, during UV irradiation, the TiO(2)/biocidal polymer showed improved inhibition of bacterial growth against gram-negative E. coli and gram-positive S. aureus in comparison to the pristine TiO(2) nanoparticles.

Vapor deposition polymerization was applied for the fabrication of cationic polymer modified silica nanoparticles and the synthesized nanoparticles exhibited enhanced antimicrobial properties compared to bulk polycations and reduced bioadhesion on the surface of glass.

Traditional IC scaling is becoming increasingly difficult at the 22nm node and beyond. Dealing with these challenges increase product development cycle time. For continued CMOS scaling, it is essential to start design explorations in new process nodes as early as possible. Such an effort requires having Predictive Technology Models, which bridge technological and design practices, in order to assess the performance impact of future key modules. In this paper we propose a strategy that enables simultaneous investigation of advanced process and design concepts. Based on a customized predictive methodology and silicon data at 90–45nm nodes, compact transistor and interconnect models are developed for the next generation CMOS technology. We capture the heuristic device behavior during the scaling, which helps us to gain key insights that allow us to make tradeoffs of circuit performance metrics for next technology node.

This paper reviews recent development on compact modeling of multiple-gate MOSFETs. Starting with a core model based on the analytic potential solutions for the highly symmetric double-gate (DG) and surrounding-gate (SG) MOSFETs, an explicit solution to the implicit algebraic equations with high accuracy has been developed. With the addition of quantum, short-channel effects, and capacitance formulations, the core model for DG MOSFETs has been expanded into a full-blown compact model which has subsequently been calibrated and validated by FinFET hardware. In view of the various types of experimental multiple-gate MOSFETs developed, the DG and SG MOSFET models have been generalized to other less symmetric structures, including quadruple-gate, triple-gate, Omega-gate, and Pi-gate devices. Finally, research activities in other groups on multiple-gate MOSFETs are briefly summarized.

An analytic potential DG model with quantum mechanical and short channel effects is calibrated to experimental n-channel FinFET data. All C-V and I-V curves from L=10 mum to 50 nm are in excellent agreement with a single mobility model. There is evidence suggesting higher than expected currents from very short fins possibly due to strain enhanced transport effects.

In this study, a complex-mediated synthetic growth method was used to embed silver (Ag) nanoparticles in poly(vinyl alcohol) (PVAI) nanofibers in an aqueous solution. Azobisisobutyronitrile (AIBN) played a pivotal role in the preparation of the Ag–PVAI nanofibers, via its cyano groups. AIBN was used to assemble the Ag ions to form Ag complexes in the early stages of the reaction. As the reaction temperature approached 60 °C, AIBN decomposed via breakage of its C–N bonds, and thus the Ag compounds became disassembled. During this stage, Ag nanoparticles were aligned with a PVAI assistant, which acted as a gelator and stabilizer for the formation of fibrous nanostructures under magnetic stirring conditions. As a result, PVAI nanofibers (diameter: ca. 35 nm) were synthesized, with Ag nanoparticles (diameter: ca. 8 nm) embedded compactly in the inner part of the fiber. The formation of Ag–PVAI composite nanofibers was systematically investigated with field-emission scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. Additionally, we performed several control experiments and proposed a plausible mechanism for the synthesis of Ag–PVAI composite nanofibers.

Silica/polyrhodanine core/shell nanoparticles were prepared by chemical oxidation polymerization. Polymerization proceeded preferentially on the surface of the silica nanoparticles where the initiator (Fe(III) ions) was located, resulting in core/shell nanoparticles. The size of the core/shell nanoparticles could be controlled by changing the diameter of the silica core. Polyrhodanine-coated silica nanoparticles exhibited excellent biocidal activities against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus. It was confirmed that the bactericidal properties of the silica/polyrhodanine core/shell nanoparticles were due to the biocide contacting the bacteria. Additionally, bactericidal performance was enhanced with decreasing biocidal nanoparticle diameter due to increased surface area.

Ferromagnetic gamma-Fe(2)O(3)/polyrhodanine nanoparticles with average diameters of ca. 10 nm were prepared by a one-step synthetic procedure and applied as a recyclable antibacterial agent towards Gram-negative/positive bacteria.

Purpose: As preoperative diagnostic tools have advanced, the rate of multiple early gastric cancer diagnoses have increased. The author investigated the clinicopathological features of multiple early gastric cancers to elucidate the clinical feasibility of minimally invasive gastrectomy such as laparoscopy or robot assisted gastrectomy for their surgical treatment. Methods: One thousand one hundred and eighty-five open gastrectomies and 607 laparoscopies or robot-assisted gastrectomies for gastric cancers from January 2003 through August 2009 were retrospectively reviewed. Among them, 844 were diagnosed as early gastric cancers, of which 47 cases had multiple early gastric cancers. Twenty-seven cases underwent open gastrectomy and 20 cases underwent laparoscopy or robot assisted gastrectomy. The author analyzed clinicopathological features in these multiple early gastric cancers. Results: The incidences of multiple early gastric cancers among the early gastric cancers were 5.6%. There were no statistical differences in the clinicopathological parameters except the type of gastrectomy and anastomosis. The distances of both proximal and distal margin show no statistical difference in both groups. The hospital stay was shorter in laparoscopy or robot assisted gastrectomy group (P=0.022). The postoperative complications developed 7 cases in open group and 1 case in laparoscopy or robot assisted gastrectomy group (P=0.046). During the mean follow-up period of and months, no recurrence was found in both groups. Conclusion: Laparoscopy or robot assisted gastrectomy are as acceptable as open methods to obtain a safe surgical margin, and to perform the desirable type of gastrectomy and radical lymph node dissection.