Extra-luminal detection of assumed colonic tumor site by near-infrared laparoscopy.

BACKGROUND: Localization of colorectal tumors during laparoscopic surgery is generally performed by tattooing into the submucosal layer of the colon. However, faint and diffuse tattoos may lead to difficulties in recognizing cancer sites, resulting in inappropriate resection of the colon. We previously demonstrated that yttrium oxide nanoparticles doped with the rare earth ions (ytterbium and erbium) (YNP) showed strong near-infrared (NIR) emission under NIR excitation (1550 nm emission with 980 nm excitation). NIR light can penetrate deep tissues. In this study, we developed an NIR laparoscopy imaging system and demonstrated its use for accurate resection of the colon in swine. METHODS: The NIR laparoscopy system consisted of an NIR laparoscope, NIR excitation laser diode, and an NIR camera. Endo-clips coated with YNP (NIR clip), silicon rubber including YNP (NIR silicon mass), and YNP solution (NIR ink) were prepared as test NIR markers. We used a swine model to detect an assumed colon cancer site using NIR laparoscopy, followed by laparoscopic resection. The NIR markers were fixed at an assumed cancer site within the colon by endoscopy. An NIR laparoscope was then introduced into the abdominal cavity through a laparoscopy port. RESULTS: NIR emission from the markers in the swine colon was successfully recognized using the NIR laparoscopy imaging system. The position of the markers in the colon could be identified. Accurate resection of the colon was performed successfully by laparoscopic surgery under NIR fluorescence guidance. The presence of the NIR markers within the extirpated colon was confirmed, indicating resection of the appropriate site. CONCLUSIONS: NIR laparoscopic surgery is useful for colorectal cancer site recognition and accurate resection using laparoscopic surgery.

Cancer-targeted near infrared imaging using rare earth ion-doped ceramic nanoparticles.

The use of near-infrared (NIR) light over 1000 nm (OTN-NIR or second NIR) is advantageous for bioimaging because it enables deep tissue penetration due to low scattering and autofluorescence. In this report, we describe the application of rare earth ion-doped ceramic nanoparticles to cancer-targeted NIR imaging using erbium and ytterbium ion-doped yttrium oxide nanoparticles (YNP) functionalized with streptavidin via bi-functional PEG (SA-YNP). YNP has NIR emission at 1550 nm, with NIR excitation at 980 nm (NIR-NIR imaging). Cancer-specific NIR-NIR imaging was demonstrated using SA-YNP and biotinylated antibodies on cancer cells and human colon cancer tissues. NIR-NIR imaging through porcine meat of 1 cm thickness was also demonstrated, supporting the possible application of deep tissue NIR-NIR bioimaging using YNP as a probe. Our results suggest that non-invasive imaging using YNP has great potential for general application in cancer imaging in living subjects.

Synthesis, characterization and observation of antisite defects in LiNiPO4 nanomaterials.

Structural studies of high voltage cathode materials are necessary to understand their chemistry to improve the electrochemical performance for applications in lithium ion batteries. LiNiPO4 nanorods and nanoplates are synthesized via a one pot synthesis using supercritical fluid process at 450 °C for 10 min. The X-ray diffraction (XRD) analysis confirmed that LiNiPO4 phase is well crystallized, phase purity supported by energy dispersive spectroscopy (EDS) and elemental mapping by scanning electron transmission electron microscopy (STEM). For the first time, we have carried out direct visualization of atom-by-atom structural observation of LiNiPO4 nanomaterials using high-angle annular dark-field (HAADF) and annular bright-field (ABF) scanning transmission electron microscopy (STEM) analysis. The Rietveld refinement analysis was performed to find out the percentage of antisite defects presents in LiNiPO4 nanoplates and about 11% of antisite defects were found. Here, we provide the direct evidence for the presence of Ni atoms in Li sites and Li in Ni sites as an antisite defects are provided for understanding of electrochemical behavior of high voltage Li ion battery cathode materials.

Calcination-free micromolding in capillaries for nanopatterning of inorganic upconversion luminescent layers on flexible plastic sheets.

We report calcination-free micromolding in capillaries for the nanopatterning of inorganic upconversion luminescent layers on flexible plastic sheets. We prepared Er(3+)- and Yb(3+)-codoped NaYF4 nanoparticles modified with a cationic polymer to improve dispersion stability of aqueous dispersion of the NaYF4 nanoparticles. We controlled the line width and density of nanoparticles in the NaYF4 nanoparticle films on flexible plastic sheets by adjusting the concentrations of the NaYF4 nanoparticle dispersion and the channel sizes of silicone stamps, resulting in the formation of nanopatterned NaYF4 nanoparticle films at the line width of the nanoparticle size (50 nm). Visible upconversion luminescence and near-infrared fluorescence appeared from the NaYF4 nanoparticle films excited with a near-infrared laser beam. These results demonstrate that calcination free micromolding in capillaries using aqueous dispersion of NaYF4 nanoparticles modified with a cationic polymer allows for the nanopatterning of inorganic upconversion luminescent layers on flexible plastic sheets.

Polytype and stacking faults in the Li2CoSiO4 Li-ion battery cathode.

Atomic-resolution imaging of the crystal defects of cathode materials is crucial to understand their formation and the correlation between the structure, electrical properties, and electrode performance in rechargeable batteries. The polytype, a stable form of varied crystal structure with uniform chemical composition, holds promise to engineer electronic band structure in nanoscale homojunctions.1-3 Analyzing the exact sites of atoms and the chemistry of the boundary in polytypes would advance our understanding of their formation and properties. Herein, the polytype and stacking faults in the lithium cobalt silicates are observed directly by aberration-corrected scanning transmission electron microscopy. The atomic-scale imaging allows clarification that the polytype is formed by stacking of two different close-packed crystal planes in three-dimensional space. The formation of the polytype was induced by Li-Co cation exchange, the transformation of one phase to the other, and their stacking. This finding provides insight into intrinsic structural defects in an important Li2 CoSiO4 Li-ion battery cathode.

Calcination-free micropatterning of rare-earth-ion-doped nanoparticle films on wettability-patterned surfaces of plastic sheets.

We demonstrate a patterning technique of rare-earth-ion-doped (RE) nanoparticle films directly on wettability-patterned surfaces fabricated on plastic sheets in one step. Self-assembled monolayers consisting of silane-coupling agent with hydrophobic groups were fabricated on plastic sheets. UV-ozone treatments were performed through a metal mask to selectively remove the self-assembled monolayers in a patterned manner, resulting in the formation of wettability-patterned surfaces on plastic sheets. Using a water dispersion of Er(3+) and Yb(3+)-codoped Y2O3 nanoparticles at a diameter of 100 nm, RE-nanoparticle films were fabricated on the wettability-patterned surfaces by a dip-coating technique. By adjusting the concentration of RE-nanoparticle dispersion, withdrawal speed, and withdrawal angle, amount of RE-nanoparticles, we were able to control the structures of the RE-nanoparticle films. Fluorescence microscope observations demonstrate that visible upconversion luminescence and near-infrared fluorescence were emitted from the RE-nanoparticle films on the wettability-patterned surfaces. This technique allows for the fabrication of flexible emitting devices with long-operating life time with minimized material consumption and few fabrication steps, and for the application to sensors, emitting devices, and displays in electronics, photonics, and bionics in the future.

Upconverting and NIR emitting rare earth based nanostructures for NIR-bioimaging.

In recent years, significant progress was achieved in the field of nanomedicine and bioimaging, but the development of new biomarkers for reliable detection of diseases at an early stage, molecular imaging, targeting and therapy remains crucial. The disadvantages of commonly used organic dyes include photobleaching, autofluorescence, phototoxicity and scattering when UV (ultraviolet) or visible light is used for excitation. The limited penetration depth of the excitation light and the visible emission into and from the biological tissue is a further drawback with regard to in vivo bioimaging. Lanthanide containing inorganic nanostructures emitting in the near-infrared (NIR) range under NIR excitation may overcome those problems. Due to the outstanding optical and magnetic properties of lanthanide ions (Ln(3+)), nanoscopic host materials doped with Ln(3+), e.g. Y2O3:Er(3+),Yb(3+), are promising candidates for NIR-NIR bioimaging. Ln(3+)-doped gadolinium-based inorganic nanostructures, such as Gd2O3:Er(3+),Yb(3+), have a high potential as opto-magnetic markers allowing the combination of time-resolved optical imaging and magnetic resonance imaging (MRI) of high spatial resolution. Recent progress in our research on over-1000 nm NIR fluorescent nanoprobes for in vivo NIR-NIR bioimaging will be discussed in this review.

Micromolding in capillaries for calcination-free fabrication of flexible inorganic phosphor films consisting of rare-earth-ion-doped nanoparticles.

We discuss the micromolding in capillaries technique for the direct fabrication of calcination-free rare earth ion-doped (RE) phosphor films consisting of RE nanoparticles on plastic sheets. We synthesized two types of RE nanoparticles consisting of Y2O3 matrix doped with Er and Yb ions. Green upconversion luminescence, red upconversion luminescence, and near-infrared fluorescence appeared from the RE nanoparticles under excitation of near-infrared light. Adjusting the channel width and depth of polydimethylsiloxane molds led to control of the density of nanoparticles in the patterned RE nanoparticle films. Adjusting concentration of the RE nanoparticle dispersion and size of the RE nanoparticles allowed for the control of the density of nanoparticles in the patterned RE nanoparticle films. The density of nanoparticles in the patterned RE films on plastic sheets increased with an increase in the number of injection and drying of the RE nanoparticle dispersion. These results demonstrate that this technique enables us to directly fabricate the patterned RE phosphor films on plastic sheets, leading to the fabrication of inorganic flexible devices with small fabrication steps and material consumptions.

Cytotoxic aspects of gadolinium oxide nanostructures for up-conversion and NIR bioimaging.

Bioimaging is an important diagnostic tool in the investigation and visualization of biological phenomena in cells and in medicine. In this context, up-converting Gd(2)O(3):Er(3+),Yb(3+) nanostructures (nanoparticles, nanorods) have been synthesized by precipitation methods and hydrothermal synthesis. Independent of size and morphology, Gd(2)O(3):Er(3+),Yb(3+) powders show up-conversion (550 nm, 670 nm) and near-infrared emission (1.5 µm) upon 980 nm excitation, which makes these structures interesting for application as biomarkers. With regard to their potential application in bioimaging, cytotoxicity is an important aspect and is strongly affected by the physico-chemical properties of the investigated nanostructures. Therefore, the cytotoxic effect of bare and poly(ethylene glycol)-b-poly(acrylic acid) block co-polymer-modified nanostructures on non-phagocytic and phagocytic cells (B-cell hybridoma cells and macrophages) was investigated. The observed cytotoxic behavior in the case of macrophages incubated with bare nanostructures was assigned to the poor chemical durability of gadolinium oxide, but could be overcome by surface modification.

Calcination-free liftoff photolithography of mixed dip-coated films consisting of rare-Earth-ion-doped nanoparticles on plastic sheets.

We discuss the calcination-free liftoff photolithography of inorganic phosphor films consisting of two kinds of rare-earth-ion-doped (RE) nanoparticles dip-coated onto plastic sheets. Green and red upconversion luminescence were emitted from the RE-nanoparticles prepared from Y2O3 nanoparticles doped with 1 mol% Er³âº and 0.75 mol% Yb³âº (RE-1-nanoparticles) and those doped with 3 mol% Er³âº and 7 mol% Yb³âº (RE-2-nanoparticles), respectively. Near-infrared (NIR) fluorescence was also observed in the RE-1- and RE-2-nanoparticles. The visible transmittance of the RE-nanoparticle films was more than 90%. The intensity ratio of the green to red upconversion luminescence was controlled by adjusting the mixing ratio of the RE-1- and RE-2-nanoparticles. These results indicate that the multicolor-emitting devices can be fabricated easily for applications of flexible inorganic phosphor films to displays, emitting devices, and sensors with long operating lifetimes and resistance to UV light, air, and water.

In vitro and in vivo investigations of upconversion and NIR emitting Gd2O3:Er³âº,Yb³âº nanostructures for biomedical applications.

The use of an "over 1000-nm near-infrared (NIR) in vivo fluorescence bioimaging" system based on lanthanide containing inorganic nanostructures emitting in the visible and NIR range under 980-nm excitation is proposed. It may overcome problems of currently used biomarkers including color fading, phototoxicity and scattering. Gd(2)O(3):Er(3+),Yb(3+) nanoparticles and nanorods showing upconversion and NIR emission are synthesized and their cytotoxic behavior is investigated by incubation with B-cell hybridomas and macrophages. Surface modification with PEG-b-PAAc provides the necessary chemical durability reducing the release of toxic Gd(3+) ions. NIR fluorescence microscopy is used to investigate the suitability of the nanostructures as NIR-NIR biomarkers. The in vitro uptake of bare and modified nanostructures by macrophages is investigated by confocal laser scanning microscopy. In vivo investigations revealed nanostructures in liver, lung, kidneys and spleen a few hours after injection into mice, while most of the nanostructures have been removed from the body after 24 h.

Co(OH)3 nanobelts: synthesis, characterization and shape-preserved transformation to pseudo-single-crystalline Co3O4 nanobelts.

In this paper, we demonstrated a facile hydrothermal route leading to the generation of a new cobalt hydroxide, Co(OH)(3), nanobelt. This new product of Co(OH)(3) nanobelts was well characterized and identified by SEM, TEM, XRD, EDX, XPS, EXAFS, Raman, TGA and SQUID. Additionally, through systematic investigations on morphological evolution, it was found that the size and shape of Co(OH)(3) nanobelts were adjustable in large scale, e.g. from 50 to 1.5 microm in length and 5 microm to 20 nm in width, by means of fine experimental parameter control. Furthermore, the unique pseudo-single-crystalline Co(3)O(4) nanobelts were produced from Co(OH)(3) precursors via heating treatment. This is the first synthesis of Co(OH)(3) with tunable shapes and sizes, which may find important applications as gas sensors, catalysts, and electrode materials, owing to the specific large surface-to-volume ratio and other unique properties endowed by typical 1D nanobelts.

Effect of sucrose on ascorbate level and expression of genes involved in the ascorbate biosynthesis and recycling pathway in harvested broccoli florets.

The relationship between sucrose (Suc) and ascorbate (AA) metabolism was investigated in harvested broccoli (Brassica oleracea L. var. italica) florets. Decreases in both Suc and AA content were observed in broccoli florets 48 h after all the leaves were excised, but none were observed when the plants were kept intact or with leaves attached in a room at 20 degrees C. In harvested broccoli plants without leaves and roots, continuous absorption of a 10% (w/v) Suc solution from the cut surface of the stem suppressed the degreening of sepals and the loss of AA content in florets. The expression of the genes related to AA metabolism in chloroplasts and its biosynthesis were up-regulated by Suc feeding in broccoli florets. These data suggest that a decline in Suc leads to considerable damage not only to AA biosynthesis but also to the hydrogen peroxide-scavenging system in chloroplasts. In addition, the cessation of the Suc supply from leaves can be the main factor of AA degradation in harvested broccoli florets.

Accumulation of carotenoids and expression of carotenoid biosynthetic genes during maturation in citrus fruit.

The relationship between carotenoid accumulation and the expression of carotenoid biosynthetic genes during fruit maturation was investigated in three citrus varieties, Satsuma mandarin (Citrus unshiu Marc.), Valencia orange (Citrus sinensis Osbeck), and Lisbon lemon (Citrus limon Burm.f.). We cloned the cDNAs for phytoene synthase (CitPSY), phytoene desaturase (CitPDS), zeta-carotene (car) desaturase (CitZDS), carotenoid isomerase (CitCRTISO), lycopene beta-cyclase (CitLCYb), beta-ring hydroxylase (CitHYb), zeaxanthin (zea) epoxidase (CitZEP), and lycopene epsilon-cyclase (CitLCYe) from Satsuma mandarin, which shared high identities in nucleotide sequences with Valencia orange, Lisbon lemon, and other plant species. With the transition of peel color from green to orange, the change from beta,epsilon-carotenoid (alpha-car and lutein) accumulation to beta,beta-carotenoid (beta-car, beta-cryptoxanthin, zea, and violaxanthin) accumulation was observed in the flavedos of Satsuma mandarin and Valencia orange, accompanying the disappearance of CitLCYe transcripts and the increase in CitLCYb transcripts. Even in green fruit, high levels of beta,epsilon-carotenoids and CitLCYe transcripts were not observed in the juice sacs. As fruit maturation progressed in Satsuma mandarin and Valencia orange, a simultaneous increase in the expression of genes (CitPSY, CitPDS, CitZDS, CitLCYb, CitHYb, and CitZEP) led to massive beta,beta-xanthophyll (beta-cryptoxanthin, zea, and violaxanthin) accumulation in both the flavedo and juice sacs. The gene expression of CitCRTISO was kept low or decreased in the flavedo during massive beta,beta-xanthophyll accumulation. In the flavedo of Lisbon lemon and Satsuma mandarin, massive accumulation of phytoene was observed with a decrease in the transcript level for CitPDS. Thus, the carotenoid accumulation during citrus fruit maturation was highly regulated by the coordination of the expression among carotenoid biosynthetic genes. In this paper, the mechanism leading to diversity in beta,beta-xanthophyll compositions between Satsuma mandarin and Valencia orange was also discussed on the basis of the substrate specificity of beta-ring hydroxylase and the balance of expression between upstream synthesis genes (CitPSY, CitPDS, CitZDS, and CitLCYb) and downstream synthesis genes (CitHYb and CitZEP).

Ascorbate metabolism in harvested broccoli.

The ascorbate content declined rapidly in broccoli (Brassica oleracea L. var. italica) florets, but not in the stem tissue, during post-harvest senescence. Ascorbate peroxidase (APX), ascorbate oxidase (AO), l-galactono-1,4-lactone dehydrogenase (GLDH), monodehydroascorbate reductase (MDAR), dehydroascorbate reductase (DHAR), and glutathione reductase (GR) were investigated in gene expression after harvest in both florets and the stem tissue of broccoli. Cytosolic gene expressions (BO-APX 1, BO-APX 2, BO-AO, BO-MDAR 2, and BO-GR) were stimulated actively in broccoli florets after harvest. By contrast, it was observed that mRNA levels of chloroplastic APX, BO-sAPX and BO-tbAPX, had decreased by 12 h after harvest in broccoli florets, suggesting that the active oxygen species (AOS) scavenging system in chloroplasts was largely abolished in florets during the early hours of the post-harvest period. In addition, gene expressions in GLDH and other chloroplastic enzymes such as BO-MDAR 1 and BO-DHAR decreased rapidly within 24 h after harvest. Ethylene treatment had no effect on the ascorbate level and the expression of all genes investigated. The expressions of BO-GLDH and chloroplastic genes (BO-sAPX, BO-tbAPX, BO-MDAR 1, and BO-DHAR) mRNA were suppressed by treatment with methyl jasmonate (MJ) and abscisic acid (ABA) and were accompanied by the acceleration of ascorbate degradation. These data suggest that ascorbate metabolism tends to be inactivated in chloroplasts by transcriptional regulation, but not in the cytosol, when ascorbate decreases under stress conditions.

[POCT and system].

POCT refers to a medical test which is carried out at sites other than a central laboratory. It includes a simple test that medical service staff carry out at the scene of a medical treatment and self-care tests that patients can perform by themselves at home. This concept has been established in the U.S. since the late 1980's. In recent years, doctor's offices and clinics have been leaders in primary care and are now paying close attention to immediate testing facilities inside their hospitals to provide better service to patients. Now, we can see more and more POCT equipment being introduced to such places. Since it is unlikely that specially trained technicians can staff the hospital around the clock, physicians or nurses have must operate the POCT instrument themselves. Based on this fact, easily accessible instruments that produce reliable data are strongly required. ARKRAY introduces the "CARE LAB" system that combines special data management software "MEQNET" with various POCT devices. These systems facilitate establishing an "in-clinic inspection station" in a general practitioner or clinic. This article presents detailed information on various POCT products and the "MEQNET" program that make up the "CARE LAB" System.