Application of fluorescence lifetime imaging of enhanced green fluorescent protein to intracellular pH measurements.

We have shown that the intracellular pH of a single HeLa cell expressing the enhanced green fluorescent protein (EGFP) can be imaged using the fluorescence lifetime of EGFP, which can be interpreted in terms of the pH-dependent ionic equilibrium of the p-hydroxybenzylidene-imidazolidinone structure of the chromophore of EGFP.

Hepatitis B caused by a hepatitis B surface antigen escape mutant.

Amino acid substitutions within the S gene involving the major antigenic a determinant of the hepatitis B virus (HBV) surface antigen (HBsAg) have been detected in cases of failure of immunization against the virus. Our report showed development of clinical hepatitis in presence of antibody to HBsAg in a healthy individual. A single amino acid substitution (G145R) within the a determinant of the HBsAg was determined by sequencing of the isolated HBV strain.

Implementation of a new neurochip using stochastic logic.

Even though many neurochips have been developed and investigated, the best suitable way for implementation has not been known clearly. Our approach is to exploit stochastic logic for various operations required for neural functions. The advantage of stochastic logic is that complex operations can be implemented with a few ordinary logic gates.

Temporal and spatial localization of three germline-specific proteins in medaka.

We show that germline-specific proteins, olvas (vasa), nanos, and tdrd1 (tudor), alter their localization in the cytoplasm during germline development in the medaka (Oryzias latipes). By immunohistochemical analysis, these three germline-specific proteins were detectable on granule-like structures in the cytoplasm of migrating primordial germ cells. In the germ cells of the gonadal primordia, these granules formed a hollow area lacking these three protein components.

Regulated motion of glycoproteins revealed by direct visualization of a single cargo in the endoplasmic reticulum.

The quality of cargo proteins in the endoplasmic reticulum (ER) is affected by their motion during folding. To understand how the diffusion of secretory cargo proteins is regulated in the ER, we directly analyze the motion of a single cargo molecule using fluorescence imaging/fluctuation analyses. We find that the addition of two N-glycans onto the cargo dramatically alters their diffusion by transient binding to membrane components that are confined by hyperosmolarity.

Analysis of the molecular dynamics of medaka nuage proteins by fluorescence correlation spectroscopy and fluorescence recovery after photobleaching.

The nuage is a unique organelle in animal germ cells that is known as an electron-dense amorphous structure in the perinuclear region. Although the nuage is essential for primordial germ cell (PGC) determination and development, its roles and functions are poorly understood. Herein, we report an analysis of the diffusion properties of the olvas gene product of the medaka fish (Oryzias lapites) in PGCs prepared from embryos, using fluorescence correlation spectroscopy and fluorescence recovery after photobleaching.

Intrathoracic ganglioneuroma in an elderly patient over 70 years of age.

We herein present an exceedingly rare case of intrathoracic ganglioneuroma that was surgically resected in an elderly patient over 70 years of age. A 74-year-old woman was asymptomatic, but a computed tomography (CT) scan of the thorax indicated the presence of a posterior mediastinal mass paravertebrally. A thoracotomy was thus performed under a strongly suggested diagnosis of a neurogenic tumor because of the appearance and position of the mass on the chest CT and magnetic resonance imaging findings, and measuring 6.

A novel lepidopteran sex pheromone produced by females of a Lithosiinae species, Lyclene dharma dharma, in the family of Arctiidae.

Female moths of Lyclene dharma dharma (Arctiidae, Lithosiinae) produced three pheromone components (I-III), which strongly stimulated male antennae. Using GC-MS analysis and chemical derivatizations, the following structures were estimated: 6-methyl-2-octadecanone (I), 14-methyl-2-octadecanone (II), and 6,14-dimethyl-2-octadecanone (III). While the stereochemistry of the chiral centers could not be determined because it was difficult to collect a sufficient amount of the natural pheromone, the plain structures of I and II were confirmed by synthesis of the racemic mixtures starting from diols.

Direct quantification of gene expression using fluorescence correlation spectroscopy.

Among the methods for single molecule detection in the field of medicinal chemistry, the importance of fluorescence correlation spectroscopy (FCS) is growing. FCS has the advantage of permitting us to determine the number of fluorescent molecules and the diffusion constant dependent on the molecular weight without any physical separation process such as gel electrophoresis. Thus this method is appropriate for studies on the hybridization of fluorescence-labeled oligonucleotides with RNA or DNA as well as gene expression through translation of a target protein linked with green fluorescent protein.

Effect of cholesterol on diffusion in surfactant bilayers.

Biological membranes consist of lipid bilayers with liquid-ordered and liquid-disordered phases. It is believed that cholesterol controls the size of the microdomains in the liquid-ordered phase and thereby affects the mobility as well as the permeability of the membrane. We study this process in a model system consisting of the nonionic surfactant C(12)E(5) and water in the lamellar phase.

Diffuse hepatocellular calcification developing in a patient on chronic hemodialysis after ischemic hepatitis.

Diffuse hepatic calcification is a rare condition. Previous reports have described patients with end-stage renal disease who developed diffuse hepatic calcification after ischemic hepatitis caused by shock. We herein present a similar case.

Preparation and characterization of thiacalix[4]arene coated water-soluble CdSe/ZnS quantum dots as a fluorescent probe for Cu2+ ions.

Highly fluorescent water-soluble CdSe/ZnS (core/shell) quantum dots (QDs) as a fluorescent Cu2+ ion probe were synthesized using thiacalix[4]arene carboxylic acid (TCC) as a surface coating agent. Hydrophobic trioctylphosphine oxide (TOPO) capped CdSe/ZnS QDs were overcoated with TCC in tetrahydrofuran at room temperature, and deprotonation of the carboxyl groups of TCC resulted in the formation of water-soluble QDs. The surface structure of the QDs was characterized by using transmission electron microscopy (TEM) and fluorescence correlation spectroscopy (FCS).

Bone mineral density in older adult patients with rheumatoid arthritis: an analysis of NHANES III.

Objective: Several studies suggest that bone mineral density (BMD) is reduced in rheumatoid arthritis (RA). However, it is unclear whether this relationship holds in a representative community-based typical RA population. We examined the relationship between BMD and RA in a representative US population-based sample from the Third National Health and Nutrition Examination Survey (NHANES III: 1988-1994).

Detection of prion protein immune complex for bovine spongiform encephalopathy diagnosis using fluorescence correlation spectroscopy and fluorescence cross-correlation spectroscopy.

Fluorescence correlation spectroscopy (FCS) and fluorescence cross-correlation spectroscopy (FCCS) are powerful techniques to measure molecular interactions with high sensitivity in homogeneous solution and living cells. In this study, we developed methods for the detection of prion protein (PrP) using FCS and FCCS. A combination of a fluorescent-labeled Fab' fragment and another anti-PrP monoclonal antibody (mAb) enabled us to detect recombinant bovine PrP (rBoPrP) using FCS because there was a significant difference in the diffusion coefficients between the labeled Fab' fragment and the trimeric immune complex consisting of rBoPrP, labeled Fab' fragment, and another anti-PrP mAb.

Bone mineral density in adults with the metabolic syndrome: analysis in a population-based U.S. sample.

Background: The metabolic syndrome is associated with low-grade inflammation. It has been suggested that proinflammatory cytokines and low-grade systemic inflammation activate bone resorption and may lead to reduced bone mineral density (BMD), but no previous studies have evaluated the association between the metabolic syndrome and BMD. We examined this relationship in a representative U.

Dissociation of the insulin receptor and caveolin-1 complex by ganglioside GM3 in the state of insulin resistance.

Membrane microdomains (lipid rafts) are now recognized as critical for proper compartmentalization of insulin signaling. We previously demonstrated that, in adipocytes in a state of TNFalpha-induced insulin resistance, the inhibition of insulin metabolic signaling and the elimination of insulin receptors (IR) from the caveolae microdomains were associated with an accumulation of the ganglioside GM3. To gain insight into molecular mechanisms behind interactions of IR, caveolin-1 (Cav1), and GM3 in adipocytes, we have performed immunoprecipitations, cross-linking studies of IR and GM3, and live cell studies using total internal reflection fluorescence microscopy and fluorescence recovery after photobleaching techniques.

Detection of polyglutamine protein oligomers in cells by fluorescence correlation spectroscopy.

Abnormal aggregation of misfolded proteins and their deposition as inclusion bodies in the brain have been implicated as a common molecular pathogenesis of neurodegenerative diseases including Alzheimer, Parkinson, and the polyglutamine (poly(Q)) diseases, which are collectively called the conformational diseases. The poly(Q) diseases, including Huntington disease and various types of spinocerebellar ataxia, are caused by abnormal expansions of the poly(Q) stretch within disease-causing proteins, which triggers the disease-causing proteins to aggregate into insoluble beta-sheet-rich amyloid fibrils. Although oligomeric structures formed in vitro are believed to be more toxic than mature amyloid fibrils in these diseases, the existence of oligomers in vivo has remained controversial.

Altered coronary vasomotor function in young patients with systemic lupus erythematosus.

Objective: Accelerated atherosclerosis is an important cause of morbidity and mortality in patients with systemic lupus erythematosus (SLE). Altered coronary microvascular function may act as a marker of changes that predispose to the development of significant coronary vascular disease. The purpose of this study was to compare coronary flow reserve (CFR) in a group of premenopausal women with SLE and a group of age-, sex-, and race-matched healthy control subjects.

Triplet fraction buildup effect of the DNA-YOYO complex studied with fluorescence correlation spectroscopy.

DNA fragments of various lengths and YOYO-1 iodide (YOYO) were mixed at various ratios, and fluorescence was measured using fluorescence correlation spectroscopy. The number of substantially emitting YOYO molecules binding to the DNA and the binding intervals between the YOYO molecules were estimated for DNA-YOYO complexes of various lengths. In the present study, we found an interesting phenomenon: triplet buildup.

DNA microstructure based on self-assembly of 4-sticky-end Holliday junctions in aqueous solution.

Liverwort-like DNA microscale structures consist of 4-sticky-end Holiday junctions as DNA bricks that can be used in nanotechnology and nanobiotechnology to direct the self-assembly of nanomachines as well as DNA assembly. Previously it has not been possible to obtain such DNA microscale structural forms, but herein we report construction of a mesh-like material made up of 4 strands of 40-base DNA. Advanced bioimaging techniques such as fluorescence correlation spectroscopy (FCS), laser scanning microscopy (LSM), and atomic force microscopy (AFM) help us as ultrasensitive detection tools for examing structures in solutions.

Specificity and similarity of functions of the Aux/IAA genes in auxin signaling of Arabidopsis revealed by promoter-exchange experiments among MSG2/IAA19, AXR2/IAA7, and SLR/IAA14.

As indicated by various and some overlapped phenotypes of the dominant mutants, the Aux/IAA genes of Arabidopsis (Arabidopsis thaliana) concomitantly exhibit a functional similarity and differentiation. To evaluate the contributions of their expression patterns determined by promoter activity and molecular properties of their gene products to Aux/IAA function, we examined phenotypes of transgenic plants expressing the green fluorescent protein (GFP)-tagged msg2-1/iaa19, axr2-1/iaa7, or slr-1/iaa14 cDNA by the MSG2 or AXR2 promoter. When driven by the MSG2 promoter (pMSG2), each GFP-tagged cDNA caused the msg2-1 phenotype, that is, the wild-type stature in the mature-plant stage, long and straight hypocotyls in the dark, reduced lateral root formation, relatively mild agravitropic traits in hypocotyls, and a normal gravitropic response in roots.

Haploinsufficiency of 8p22 may influence cancer-specific survival in prostate cancer.

Although Knudson's two-hit hypothesis with functional loss of a tumor suppressor gene has been widely accepted, accumulating evidence suggests that several genes are regulated by the quantity of their product in a dose-dependent manner (gene dosage effect). The study was designed to identify the influence of gene dosage effect of 8p22 on patient prognosis. With a median age of 71 years, 40 patients with prostate cancer (11 organ-confined, 13 capsular penetrating, and 16 nodal and/or distant metastatic) were followed for a median of 68.