Development of silica-coated silver iodide nanoparticles and their biodistribution.

Nanomaterials have great potential in the field of medicine and have been studied extensively. In a previous study, we addressed the potential of silver iodide (AgI) as X-ray contrast media, because it possessed high imaging ability in the measurement by X-ray computed tomography (X-CT) in vitro, and its surface can be modified with many functional groups. We developed the method of silica coating to make AgI nanoparticles more stable and uniform in size.

Synthesis of high concentration colloid solution of silica-coated AgI nanoparticles.

Methods for high concentration silica-coated silver iodide (AgI/SiO2) particles, which could be practically used as X-ray contrast agent, were examined. The first was a single-step method, which was to prepare AgI nanoparticles at an AgI concentration of 5 x 10(-3) M and coat the AgI nanoparticles with silica shell by a Stöber method. The second was a multiple-step method, which was to repeat a step for preparing a AgI/SiO2 particle colloid solution with 10(-3) M AgI 5 times for adjusting a final AgI concentration to 5 x 10(-3) M.

Blood oxygenation using microbubble suspensions.

Microbubbles have been used in a variety of fields and have unique properties, for example shrinking collapse, long lifetime, efficient gas solubility, a negatively charged surface, and the ability to produce free radicals. In medicine, microbubbles have been used mainly as diagnostic aids to scan various organs of the body, and they have recently been investigated for use in drug and gene delivery. However, there have been no reports of blood oxygenation by use of oxygen microbubble fluids without shell reagents.

Synthesis and pharmacological characterization of potent, selective, and orally bioavailable isoindoline class dipeptidyl peptidase IV inhibitors.

Focused structure-activity relationships of isoindoline class DPP-IV inhibitors have led to the discovery of 4b as a highly selective, potent inhibitor of DPP-IV. In vivo studies in Wistar/ST rats showed that 4b was converted into the strongly active metabolite 4l in high yield, resulting in good in vivo efficacy for antihyperglycemic activity.

Discovery and pharmacological characterization of N-[2-({2-[(2S)-2-cyanopyrrolidin-1-yl]-2-oxoethyl}amino)-2-methylpropyl]-2-methylpyrazolo[1,5-a]pyrimidine-6-carboxamide hydrochloride (anagliptin hydrochloride salt) as a potent and selective DPP-IV inhibitor.

In the course of our program for discovery of novel DPP-IV inhibitors, a series of pyrazolo[1,5-a]pyrimidines were found to be novel DPP-IV inhibitors. We identified N-[2-({2-[(2S)-2-cyanopyrrolidin-1-yl]-2-oxoethyl}amino)-2-methylpropyl]-2-methylpyrazolo[1,5-a]pyrimidine-6-carboxamide hydrochloride (4a) and described its pharmacological profiles.

In vivo imaging of the molecular distribution of the VEGF receptor during angiogenesis in a mouse model of ischemia.

Vascular endothelial growth factor (VEGF) plays a critical role in angiogenesis and has been applied to medical therapy. However, because vascular imaging at the molecular level is impossible, the detailed in vivo dynamics of VEGF and its receptor (VEGFR) remain unknown. In this study, to understand the molecular distribution of VEGF and the VEGFR, we prepared ischemic mice with a new surgical method and induced angiogenesis in the gastrocnemius muscle.

Control of shell thickness in silica-coating of Au nanoparticles and their X-ray imaging properties.

This paper describes a performance of precise control of shell thickness in silica-coating of Au nanoparticles based on a sol-gel process, and an investigation into X-ray imaging properties for the silica-coated Au (Au/SiO(2)) particles. The Au nanoparticles with a size of 16.9±1.

Synthesis of silica-coated AgI nanoparticles and immobilization of proteins on them.

This paper describes a method for preparing silica-coated silver iodide (AgI/SiO2) particles and immobilizing proteins on the AgI/SiO2 particles. Colloid solution of AgI particles was prepared by mixing AgClO4 aqueous solution and KI aqueous solution. Silica-coating of the AgI particles was performed by adding 3-mercaptopropyltrimethoxysilane, tetraethylorthosilicate/ethanol solution and NaOH aqueous solution successively to the AgI colloid solution.

Uniform silica coated fluorescent nanoparticles: synthetic method, improved light stability and application to visualize lymph network tracer.

Background: The sentinel lymph node biopsy (SLNB) was developed as a new modality in the surgical diagnosis of lymph node metastases. Dye and radioisotope are major tracers for the detection of sentinel lymph nodes (SLN). Dye tends to excessively infiltrate into the interstitium due to their small size (less than several nanometers), resulting in difficulties in maintaining clear surgical fields.

Comparison of core needle biopsy (CNB) and surgical specimens for accurate preoperative evaluation of ER, PgR and HER2 status of breast cancer patients.

The roles of core needle biopsy (CNB) have become well established as an important preoperative diagnostic method for breast lesions. We examined the concordance of histological types, nuclear grades, hormone receptors, and human epidermal growth factor receptor 2 (HER2) status between CNB and surgical specimens in 353 cases. In addition, we analyzed the correlation between the number of CNB specimens obtained and accuracy of histological factors in order to explore the optimal number of CNB specimens.

The correlation between ultrasonographic findings and pathologic features in breast disorders.

Objective: Breast ultrasonography has gained widespread acceptance as a diagnostic tool for the evaluation of human breast disorders. It is important to evaluate the correlation of ultrasonography findings with the corresponding histopathological features.

Method: We retrospectively reviewed the 154 cases of breast disorders.

Nano-imaging of the lymph network structure with quantum dots.

Sentinel lymph node diagnosis contributes to operative strategy in cancer surgery. During lymph node metastasis, cancer cells first reach the sentinel lymph node (SLN) via lymph flow. To perform SLN biopsy effectively, it is important that cancer cells are detected with high sensitivity in SLN connected to the tumor site.

Activation of caspases and apoptosis in response to low-voltage electric pulses.

Few studies have examined apoptosis induced by low-voltage electric pulses (LVEPs). LVEP-induce changes in membrane potential that are below the membrane breakdown threshold and increase membrane permeability without electroporation (pore formation) through the transport of extracellular substances via phagocytosis. We demonstrated that propidium iodide uptake and apoptosis increased in accordance with the duration and number of LVEPs in B16 cells, which showed relatively good viability under mild electric field conditions.

Total-circumference intraoperative frozen section analysis reduces margin-positive rate in breast-conservation surgery.

Objective: One problem existing in breast-conservation surgery is ipsilateral breast tumour recurrence, and one of its major risk factors is surgical margin positivity. We therefore investigated whether total-circumference surgical margin examination can reduce surgical margin-positive rates.

Methods: A total of 122 cases were examined after BCS was performed between March 2004 and March 2006.

Size-selective growth and stabilization of small CdSe nanoparticles in aqueous solution.

Using cysteine and its derivatives as capping molecules, we investigated the influence of the physical structure and chemical nature of capping molecules on the selective growth and stabilization of small CdSe nanoparticles (NPs) in aqueous solution at room temperature. Our investigations revealed specific roles for each functional group of cysteine, and we could correlate this structure and nature of the capping molecules with the size, size restriction, size distribution, and stability of the NPs. For selective growth and stabilization of the NPs in aqueous solution, their capping molecules should have at least one functional group with strong nucleophilicity as well as another free, charged functional group.

Capecitabine monotherapy is efficient and safe in all line settings in patients with metastatic and advanced breast cancer.

Objective: Capecitabine is effective and well tolerated in patients with anthracycline- and/or taxane-pre-treated metastatic breast cancer. We compared the efficacy and safety of capecitabine monotherapy between 1st, 2nd, 3rd and > or =4th line settings for advanced and metastatic breast cancer pre-treated with/without anthracycline and taxanes.

Methods: Subjects comprised 84 patients with histologically confirmed advanced or metastatic breast cancer and at least one measurable metastatic lesion.

Dynamics of different-sized solid-state nanocrystals as tracers for a drug-delivery system in the interstitium of a human tumor xenograft.

Introduction: Recent anticancer drugs have been made larger to pass selectively through tumor vessels and stay in the interstitium. Understanding drug movement in association with its size at the single-molecule level and estimating the time needed to reach the targeted organ is indispensable for optimizing drug delivery because single cell-targeted therapy is the ongoing paradigm. This report describes the tracking of single solid nanoparticles in tumor xenografts and the estimation of arrival time.

Measurement of individual red blood cell motions under high hematocrit conditions using a confocal micro-PTV system.

Developments in optical experimental techniques have helped in elucidating how blood flows through microvessels. Although initial developments were encouraging, studies on the flow properties of blood in microcirculation have been limited by several technical factors, such as poor spatial resolution and difficulty obtaining quantitative detailed measurements at such small scales. Recent advances in computing, microscopy, and digital image processing techniques have made it possible to combine a particle tracking velocimetry (PTV) system with a confocal microscope.

Effects of unique biomedical education programs for engineers: REDEEM and ESTEEM projects.

Current engineering applications in the medical arena are extremely progressive. However, it is rather difficult for medical doctors and engineers to discuss issues because they do not always understand one another's jargon or ways of thinking. Ideally, medical engineers should become acquainted with medicine, and engineers should be able to understand how medical doctors think.

Frictional characteristics of erythrocytes on coated glass plates subject to inclined centrifugal forces.

In recent years a diamond-like carbon (DLC) film and a 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer have attracted attention as coating materials for implantable artificial organs or devices. When these materials are coated on vascular devices, compatibility to blood is an important problem. The present paper focuses on friction characteristics of erythrocytes to these coating materials in a medium.

Age-specific interval breast cancers in Japan: estimation of the proper sensitivity of screening using a population-based cancer registry.

The age-specific sensitivity of a screening program was investigated using a population-based cancer registry as a source of false-negative cancer cases. A population-based screening program for breast cancer was run using either clinical breast examinations (CBE) alone or mammography combined with CBE in the Miyagi Prefecture from 1997 to 2002. Interval cancers were newly identified by linking the screening records to the population-based cancer registry to estimate the number of false-negative cases of screening program.

Early diagnosis of cancer by detecting the chemiluminescence of hematoporphyrins in peripheral blood lymphocytes.

Early detection and optimal treatment are the most effective means to improve cancer mortality. Mass screening for cancer has yielded a marked reduction of cancer mortality in the United States. Simple and effective methods are expected for screening of malignancy.

[In vivo single molecular fluorescence imaging for analysis of pharmacokinetics].

Nano-materials are expected for research on molecular imaging of pharmacokinetics. We measured in vivo migration of CdSe nano-particles(Quantum Dots(QDs))conjugated with monoclonal anti-HER2 antibody(trastuzumab)in tumor vessel to breast cancer cells. We established a high resolution in vivo 3D microscopic system for a novel imaging method at single molecular level.