A patient with colitis-associated cancer who developed clinically manifest Crohn's disease only after surgery.

BACKGROUND: Patients with prolonged inflammatory bowel disease have a greater risk of colorectal cancer, known as colitis-associated cancer. Here we describe an unusual case of colitis-associated cancer. CASE PRESENTATION: The subject is a 41-year-old male who has not presented digestive symptoms and has an appreciable medical history. He consulted a nearby doctor with left flank pain. A colonoscopy revealed a lateral spreading tumor (granular-type) in his descending colon. With a clinical diagnosis of cancer, D3 left hemicolectomy was performed and a small intestine stoma was constructed. The pathological diagnosis of the tumor was mucinous adenocarcinoma, pT4a(SE), pN2a, which was associated with dysplasia in the surface area. Post-operative ileus was prolonged and the endoscopic examination revealed longitudinal ulcers in the ileum. These ulcers responded quite well to the administration of infliximab, confirming the final diagnosis of Crohn's disease. Pathological re-examination revealed that the tumor was dysplasia-associated type, and another dysplasia was confirmed near the tumor. Furthermore, mural scars and sporadic lymphoid aggregates were noted in the colon tissues, which suggested pre-existing Crohn's disease. The patient died of peritoneal dissemination of cancer on day 207 after surgery. CONCLUSION: The present case was diagnosed as colitis-associated cancer with clinically latent Crohn's disease, who developed clinically manifest Crohn's disease only after surgery. Our review of literature revealed no cases comparable to ours.

Continuous syntheses of Pd@Pt and Cu@Ag core-shell nanoparticles using microwave-assisted core particle formation coupled with galvanic metal displacement.

Continuous synthesis of Pd@Pt and Cu@Ag core-shell nanoparticles was performed using flow processes including microwave-assisted Pd (or Cu) core-nanoparticle formation followed by galvanic displacement with a Pt (or Ag) shell. The core-shell structure and the nanoparticle size were confirmed using high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) observation and EDS elemental mapping. The Pd@Pt nanoparticles with a particle size of 6.5 ± 0.6 nm and a Pt shell thickness of ca. 0.25 nm were synthesized with appreciably high Pd concentration (Pd 100 mM). This shell thickness corresponds to one atomic layer thickness of Pt encapsulating the Pd core metal. The particle size of core Pd was controlled by tuning the initial concentrations of Na2[PdCl4] and PVP. Core-shell Cu@Ag nanoparticles with a particle size of 90 ± 35 nm and an Ag shell thickness of ca. 3.5 nm were obtained using similar sequential reactions. Oxidation of the Cu core was suppressed by the coating of Cu nanoparticles with the Ag shell.

Visual detection of arsenic using hydride generation followed by reaction with silver bis(2-ethylhexyl)dithiocarbamate retained in a support filter.

In this study, a simple and effective method for the detection of trace amounts of arsenic in water samples was developed. Arsenic hydride generated by the reduction of a water sample was passed through a sensing filter retaining silver bis(2-ethylhexyl)dithiocarbamate complex. The original yellow color of the filter immediately turned reddish violet. The difference of color was observed by a reflection spectrophotometer. Sensing filters made of glass fiber gave the highest sensitivity. Addition of low volatile amines effectively stabilized the performance of the sensing filter. Common anions including phosphate ion did not interfere with the arsenic detection. Visual detection of 10 µg dm(-3) was achieved in φ10 mm filter area using 60 cm(3) of sample solution.

Simple and rapid hydrogenation of p-nitrophenol with aqueous formic acid in catalytic flow reactors.

The inner surface of a metallic tube (i.d. 0.5 mm) was coated with a palladium (Pd)-based thin metallic layer by flow electroless plating. Simultaneous plating of Pd and silver (Ag) from their electroless-plating solution produced a mixed distributed bimetallic layer. Preferential acid leaching of Ag from the Pd-Ag layer produced a porous Pd surface. Hydrogenation of p-nitrophenol was examined in the presence of formic acid simply by passing the reaction solution through the catalytic tubular reactors. p-Aminophenol was the sole product of hydrogenation. No side reaction occurred. Reaction conversion with respect to p-nitrophenol was dependent on the catalyst layer type, the temperature, pH, amount of formic acid, and the residence time. A porous and oxidized Pd (PdO) surface gave the best reaction conversion among the catalytic reactors examined. p-Nitrophenol was converted quantitatively to p-aminophenol within 15 s of residence time in the porous PdO reactor at 40 °C. Evolution of carbon dioxide (CO2) was observed during the reaction, although hydrogen (H2) was not found in the gas phase. Dehydrogenation of formic acid did not occur to any practical degree in the absence of p-nitrophenol. Consequently, the nitro group was reduced via hydrogen transfer from formic acid to p-nitrophenol and not by hydrogen generated by dehydrogenation of formic acid.

Dynamic control of gold nanoparticle morphology in a microchannel flow reactor by glucose reduction in aqueous sodium hydroxide solution.

Continuous flow synthesis of gold nanoparticles was demonstrated using a microchannel reactor with glucose reduction in aqueous alkaline medium. Particle size, morphology, and visual/optical properties of the dispersion liquid were controlled dynamically by tuning of the rate of NaOH addition. Characteristic star-like nanoparticles formed spontaneously as a quasi-stable state, but they changed the morphology to round shape and showed spectral change over time.

Pelioid-type well-differentiated hepatocellular carcinoma in a patient with a history of taking oral contraceptives: report of a case.

We report a case of pelioid-type well-differentiated hepatocellular carcinoma (HCC) in a 54-year-old woman with a history of taking oral contraceptives. She was not infected with hepatitis viruses and her liver function test results were normal. Contrast-enhanced computed tomography showed an irregular-shaped and remarkably enhanced tumor with central necrosis. The tumor was vaguely nodular without capsules, and consisted of multiple pelioid cysts and sinusoidal dilatations with transitional forms between them. The pelioid cysts were directly surrounded by neoplastic cells with fatty degeneration. Since pelioid-type HCC has similar radiological and pathological features to peliosis hepatis, it is difficult to differentiate them based on drug history and imaging studies. The detection of stromal invasion into the portal area is necessary to distinguish well-differentiated HCC from benign hepatic tumors.

Continuous synthesis of monodispersed silver nanoparticles using a homogeneous heating microwave reactor system.

Continuous synthesis of silver nanoparticles based on a polyol process was conducted using a microwave-assisted flow reactor installed in a cylindrical resonance cavity. Silver nitrate (AgNO(3)) and poly(N-vinylpyrrolidone) (PVP) dissolved in ethylene glycol were used respectively as a silver metal precursor and as a capping agent of nanoparticles. Ethylene glycol worked as the solvent and simultaneously as the reductant. Silver nanoparticles of narrow size distributions were synthesized steadily for 5 h, maintaining almost constant yield (>93%) and quality. The reaction was achieved within 2.8 s of residence time, although nanoparticles were not formed under this flow rate by conventional heating. A narrower particle size distribution was realized by the increased flow rate of the reaction solution. Nanoparticles of 9.8 nm average size with a standard deviation of 0.9 nm were synthesized at the rate of 100 ml h(-l).

Continuous process for fabrication of size controlled polyimide nanoparticles using microfluidic system.

A new strategy has been developed for continuous preparation of polyimide nanoparticles within 10 s of short residence time using a system combining a micromixer and a micro heat exchanger, where the particle size can be controlled proportionally simply by varying the concentration of poly(amic acid) (PAA).

Preparation of silica sphere with porous structure in supercritical carbon dioxide.

Silica sphere with porous structure has been synthesized in supercritical carbon dioxide. The structure originates from a delicate CO(2) trapping phenomenon intended for void formation in the inorganic framework. Silicate polymerization and subsequent removal of CO(2) by depressurization leaves the porous architecture. The key factor to obtain stable porous spherical structure was CO(2) pressure. Different characterization techniques such as X-ray diffraction, scanning and transmission electron microscopy and N(2) adsorption-desorption isotherm were used to determine the framework structure, morphology and porosity of the material. Microscopic visualization of calcined material suggested that the spherical structure was consisted of macroporous windows of diameter approximately 100 nm and the space between macropores presents a wormhole like mesoporous/microporous structure. The pore diameter of the mesoporous structure has been calculated as approximately 3 nm. X-ray diffraction and N(2) adsorption isotherm analysis confirmed the presence of micropores and also the macropores. In addition, the resulting material possess high thermal and hydrothermal stability associated with fully SiO(4) cross-linking. The spherical structure with different types of porosity was successfully obtained without using any molding agent.

Highly efficient chemoselective N-acylation with water microreaction system in the absence of catalyst.

A high-speed, highly efficient chemoselective N-acylation by anhydride was achieved in the absence of catalyst for exothermic (DeltaH>0) and endothermic (DeltaH<0) acylation of various amines and anilines with the microreaction system of ambient water (micro-onH2O) and subcritical water (micro-subH2O), where the desired N-acylated products are chemoselectively obtained with high yield(s) and excellent selectivity (>95%).

Importance of the support material in thin palladium composite membranes for steady hydrogen permeation at elevated temperatures.

Hydrogen permeation performance of palladium membranes supported on porous alpha-alumina and yttria-stabilized zirconia (YSZ) was studied at 300-850 degrees C. The hydrogen permeation flux across the palladium-alpha-alumina membrane decreased markedly during permeation tests conducted at >600 degrees C. The SEM and XPS studies of the post-test membrane revealed the presence of aluminium in the palladium layer. Such migration of aluminium was not observed by heating the palladium-alpha-alumina membrane under an argon atmosphere, indicating that hydrogen is responsible for this phenomenon. Hydrogen-induced strong metal-support interaction might be related to this considerable loss of the hydrogen flux. Reduction of alumina to Al(0) by active hydrogen at the membrane-support interface and subsequent migration of Al(0) into the palladium layer represents the most plausible mechanism for the aluminium diffusion. Actually, Al(0) that migrated into the palladium membrane layer generated less hydrogen-permeable palladium-aluminium alloy or inter-metallic compound phase. In contrast, no such strong interaction was found between the YSZ support and the palladium membrane. This composite membrane exhibited a steady permeation of hydrogen at 650 degrees C for 336 h. Having a remarkably high reduction potential, Y(III) is unlikely to be reduced to Y(0), although Zr(IV) has a comparable reduction potential to that of Al(III). A binary phase diagram shows a liquid alloy phase present for the Pd/Al couple at temperatures greater than 615 degrees C (eutectic point), while an inter-metallic compound or liquid alloy phase in the Pd-Zr binary system is not apparent at temperatures less than 750 degrees C. Consequently, inter-diffusion of zirconium with palladium did not occur during operations at 650 degrees C.

Dithizone nanofiber-coated membrane for filtration-enrichment and colorimetric detection of trace Hg(II) ion.

Dithizone nanofiber-coated membranes (dithizone membranes), which are useful for sensitive and selective determination of Hg(II), were fabricated. Simply by filtration of the aqueous dispersion of dithizone nanofiber through a cellulose ester membrane filter, a dithizone nanofiber layer of less than 500 nm thickness was coated firmly and uniformly over the membrane filter surface. The steel blue color of the membrane remained unchanged for more than three months when fabricated in the presence of ascorbic acid and stored with an oxygen absorber in an evacuated aluminium bag. Determination at the parts per billion level of Hg(II) was achieved by filtration-enrichment of a sample solution and simultaneous colorimetric analysis using a TLC scanner (500 nm). Consequently, Hg(II) ion was concentrated in the dithizone layer as reddish brown complexes by filtration of a sample solution at pH 2.7. More than 90% of 10 ppb Hg(II) was retained in the dithizone layer at the filtration rate of 1.3-9.3 ml min(-1). The presence of Na+ (10,000 ppm), K+ (5000 ppm), Ca(II) (5000 ppm), Cu(II) (6.4 ppm), Fe(II) (100 ppm), Zn(II) (100 ppm), Pb(II) (100 ppm) and Cd(II) (10 ppm) by using 2.5 x 10(-4) M of ethylenediamine tetraacetic acid (EDTA) as a masking reagent did not interfere with the detection of Hg(II) (10 ppb). Most of anions did not interfere with the determination of Hg(II). The present method was tested for the detection of simulated wastewater, river water and seawater spiked with 10 ppb of Hg(II).

An exceptionally rapid and selective hydrogenation of 2-cyclohexen-1-one in supercritical carbon dioxide.

Selective hydrogenation of 2-cyclohexen-1-one over Pt-MCM-41 proceeds at a very high rate and produces cyclohexanone with selectivity of 100% in a batch reactor; a marked increase in the reaction rate (TOF) from 2283 min(-1) to 5051 min(-1) is observed on increasing the pressure from 7 MPa to 14 MPa at 40 degrees C.

Test strips for lead(II) based on a unique color change of PVC-film containing O-donor macrocycles and an anionic dye.

Glassy test strips partially coated with PVC-film including O-donor macrocyclic receptors (L), tetrabromophenolphthalein ethyl ester (TBPE(-)), and a plasticizer sensed Pb(2+) in aqueous solutions by a unique color change. Yellow films successively changed color to green, dark-blue and purple with increases of the Pb(2+) concentration. In contrast with the ordinary "optode", a characteristic absorption band at 525 nm was newly appeared independently of the protonation and deprotonation of HTBPE (yellow to blue). The unique color change occurred only when asymmetric receptors with respect to the basal plane were coupled with Pb(2+). This optical-structural correlation is likely to be induced by the H aggregate of two sets of TBPE(-) in the 1:2 ion-pair, [Pb-L](2+).(TBPE(-))(2). The color change, based on metachromasy, was exclusive for Pb(2+) among common metal cations (Ca(2+), Al(3+), Cd(2+), Zn(2+), Fe(3+), Co(2+), Hg(2+)) and anions (Cl(-), SO(4)(2-), PO(4)(3-), S(2)O(3)(2-)).

Fluorometric determination of fluoride ion by reagent tablets containing 3-hydroxy-2'-sulfoflavone and zirconium(IV) ethylenediamine tetraacetate.

A reagent tablet for determination of fluoride ion has been prepared using ethylenediamine-N,N,N',N'-tetraacetate complex of zirconium (Zr-EDTA), 3-hydroxy-2'-flavone (FS) and an appropriate pH buffer. Dissolving of the tablet into water exhibits an intense blue fluorescence (lambda(max)=460 nm) upon excitation at 377 nm and the fluorescence intensity decreases with the presence of fluoride ion. Hence, a simple fluorescent detection procedure for fluoride ion in aqueous media was successfully constructed with this tablet. The principle of this detection system is the ligand exchange reaction of FS bound to Zr-EDTA with fluoride ion. The present system provides an easy, rapid and selective determination method of fluoride ion ranging from 5 x 10(-6) to 1 x 10(-3)mol dm(-3). The measurement of real samples with this tablet showed the similar results as those by the common method with the Alfusone reagent.

Simple detection of trace Pb2+ by enrichment on cerium phosphate membrane filter coupled with color signaling.

A Pb(2+) selective membrane filter was fabricated from the fibrous CeO(H(2)PO(4))(2).2H(2)O (CeP) crystals by blending with cellulose fiber. Enrichment of ppb level of Pb(2+) was achieved simply by filtration of aqueous sample solution through the membrane filter. Pb(2+) was strongly retained on the membrane filter by accommodation into the interlayer gallery of a CeP crystal. Visual detection of the enriched Pb(2+) was achieved by subsequent color signaling as PbS deposit upon treatment of the membrane filter with 3% Na(2)S solution. The analytical procedure and sample treatment conditions were optimized with respect to pH of the sample solution, filtration rate and masking of interfering ions. Detection of 20 ppb of Pb(2+) was not interfered by the presence of 1000-fold of Ca(2+), Mg(2+), and up to 100-fold of Fe(3+)and Cu(2+) by masking with 1 x 10(-3) mol dm(-3) of iminodiacetic acid (IDA). Most anions including phosphate (20 000 times) did not interfere with the determination of Pb(2+). The present simple method was applied to the determination of Pb(2+) in real samples like mine valley water.

Switching of PET fluorescence signals induced by ligand exchange reactions of N-(9-anthrylmethyl)amine on Cu(II) complexes and its application to postcolumn detection of glyphosate.

N-(9-Anthrylmethyl)amines which combine a fluorescent subunit and a chelate forming fragment have revealed a signal switching property in an aqueous solution upon complexation (off) with Cu(II) and liberation (on) of the probe molecule by substitution with an other ligand. The ligand exchange reaction between N-(phosphonomethyl)glycine (glyphosate), a typical herbicide, with N-(9-anthrylmethyl)amines on Cu(II) ion leads the fluorescence signal intensity to revive, providing an indirect detection system of glyphosate available in water of neutral pH region. The present system has been applied to the post column detection in the ion chromatographic separation of glyphosate and its metabolite aminomethylphosphonic acid (AMPA).

Separation and enrichment of arsenic(V) with composite resin beads containing magnetite crystals.

The adsorption of arsenic(V) was investigated using macroporous resin beads containing magnetite crystals. Arsenic(V) was favorably adsorbed at pH 2-9, where the distribution coefficients were larger than 10(3). The maximum capacity was 0.050 mmol/g. Metal cations including Ca(II), Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and La(III) did not give serious interference at 10(-4) M level. Diluted arsenic(V) was collected with a packed column, and the retained arsenic(V) was quantitatively eluted out with 1 M NaOH.

Naked-eye detection of trace arsenic(V) in aqueous media using molybdenum-loaded chelating resin having beta-hydroxypropyl-di(beta-hydroxyethyl)amino moiety.

A naked-eye detection method for a trace amount of arsenic in aqueous samples has been newly developed. The proposed method is based on the formation of a hetero poly acid in a chelating resin phase. Molybdenum loaded on a chelating resin having beta-hydroxypropyl-di(beta-hydroxyethyl) amino moiety reacts with arsenic(V) to form the hetero poly acid, which makes the resin beads greenish blue in the presence of a reducing agent under acidic conditions. It was also found that the intensity of the color of the resin depends on the concentration of arsenic(V) in the sample solutions. Since the development of the color occurs in 20min by heating of the mixture at 40 degrees C, this system can provide a simple, rapid and low-cost detection method of a trace amount of arsenic(V) in an aqueous media. The detection limit of this method is 1x10(-6)moldm(-3). A longer preconcentration time with the same resin gave the higher sensitivity of 1x10(-7)moldm(-3) that is comparable with that of the instrumental analysis. The present method comprises both the concentration and detection step with the same solid material, and hence it gives higher sensitivity and easier handling than the ordinary colorimetric methods using a liquid medium.