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Image-enhanced endoscopy (IEE) allows real-time high-contrast imaging of a targeted lesion without any special equipment. Among various IEE technologies, narrow-band imaging, in which a light of shorter wavelength is used, emphasizes the surface and blood vessel patterns on the mucosal surface. This technology has been widely used in endoscopic diagnosis in the gastrointestinal tract. Red dichromatic imaging (RDI) was recently developed; it utilizes lights of longer wavelengths (520–550, 595–610, and 620–640 nm), which have weak light scattering characteristics in contrast to narrow-band imaging. RDI was designed to enhance the visibility of deep-lying blood vessels and areas of bleeding, and it has been installed in the latest Olympus endoscopy system, EVIS X1, as an advanced version of the optical-digital method that was originally developed. Improving the visibility of deep blood vessels allows more accurate evaluation of esophageal varices and the degree of inflammation in ulcerative colitis. Easier identification of a bleeding source makes hemostasis quicker and easier to accomplish during endoscopic resection procedures such as endoscopic submucosal dissection and peroral endoscopic myotomy as well as during treatment of gastrointestinal bleeding from a peptide ulcer or colon diverticulum. The authors herein review the technological development and principles, review the existing literature on RDI, and discuss the utility and effectiveness of this unique IEE technology in gastrointestinal endoscopy. [ABSTRACT FROM AUTHOR]

A sub-10 nm, high-density, periodic silicon nanodisk (Si-ND) array with a SiC interlayer has been fabricated using a new top-down process that involves a 2D array of a bio-template etching mask and damage-free neutral beam etching. Optical and electrical measurements were carried out to clarify the formation of mini-bands due to wavefunction coupling. We found that the SiC interlayer could enhance the optical absorption coefficient in the layer of Si-NDs due to the stronger coupling of wavefunctions. Theoretical simulation also indicated that wavefunction coupling was effectively enhanced in Si-NDs with a SiC interlayer, which precisely matched the experimental results. Furthermore, the I-V properties of a 2D array of Si-NDs with a SiC interlayer were studied through conductive AFM measurements, which indicated conductivity in the structure was enhanced by strong lateral electronic coupling between neighboring Si-NDs. We confirmed carrier generation and less current degradation in the structure due to high photon absorption and conductivity by inserting the Si-NDs into p-i-n solar cells. [ABSTRACT FROM AUTHOR]

Abstract: The effect of intra-gastric infusion of skipjack tuna (Katsuwonus pelamis) muscle soluble extract and of carnosine, anserine and histidine, on pepsin-like protease activity was studied in the isolated, externally batch-cultured stomach of the rockfish (Sebastes schlegelii). Stomach was isolated from the fish, then intragastrically infused with the above solutions or with a balanced saline solution (control solution) as the stimulant at 0.1mL/min for 6h. Intra-gastric efflux was collected for measurement of pepsin-like protease activity. Skipjack tuna soluble extract, but not carnosine, anserine or histidine alone caused significant enhancement of pepsin-like protease activity during the infusion. Pepsin-like protease activity from skipjack tuna soluble extract responded immediately after infusion and was kept for 150min after infusion. Stomach motility at the end of infusion was also observed. These results suggest that isolated stomach can receive mucosal side stimulants in vitro. It is likely that some effective components for stomach digestion in fish exist in skipjack tuna soluble extract. [Copyright &y& Elsevier]

Abstract: Background: We developed a new enzyme-linked immunosorbent assay (ELISA) for ornithine carbamoyltransferase (OCT) and evaluated its usefulness. Methods: Recombinant human OCT expressed in E. coli was used as an antigen to obtain the monoclonal antibodies for this assay. Results: The reactivity of the antibodies to native OCT as well as recombinant OCT was enhanced at alkaline pH (8.5–10), and the assay''s sensitivity was markedly improved. The antibodies react identically with native and recombinant OCT at pH 9.4. The dilution test showed a good linearity between dilution ratios and the concentrations. Different concentrations of OCT added were recovered on average at 90.4%. There was a good correlation between OCT protein levels in the ELISA and OCT enzyme activities (r =0.987, p <0.0001). A significant difference in the serum level of OCT was observed between chronic hepatitis patients (110.7±80 ng/ml) and healthy subjects (34.4±20.7 ng/ml) (p <0.0001). The serum levels of OCT between sexes differed significantly in the healthy subjects (p <0.0001). Conclusions: Our newly established ELISA for OCT using monoclonal antibodies is sensitive enough for clinical application. [Copyright &y& Elsevier]

Abstract: Ice cores retrieved from ice sheets provide the most detailed records of climate over the past several hundred thousand years. For example, water-soluble impurities have been used as proxies for atmospheric chemistry. However, numerical models warned that the distributions of the trace constituents are significantly altered by rapid diffusion through liquid veins along triple junctions during ice sheet flow. Although these calculations assumed that the trace constituents are preferentially confined to grain boundaries and form a vein network, this assumption has not been confirmed experimentally. Using micro-Raman spectroscopy, here we show that most of the soluble impurities are confined as salt inclusions within grains. These inclusions are mainly composed of the sulfate salts Na2SO4·10H2O, MgSO4·12H2O, and CaSO4·2H2O. We also found that methane-sulfonate salts and other complex salts exist only in the glacial-period ice. Our findings imply that these salts form within 185 m of the ice surface and then preserve their composition as the ice is pushed to greater depths. This means that depth profiles of the trace constituents should be preserved in deep ice cores as reliable proxies for past climate. [Copyright &y& Elsevier]

We made a tissue phantom with double-peak particle size distribution, which has polystyrene particles of cell nuclear site and mitochondrial size, and measured the spectrum from the tissue phantom using a single optical fiber. In this paper we investigate the characterization method for the tissue phantom with double-peak particle size distribution by comparing the measured spectra with the calculated ones using the Monte Carlo (MC) method. It is first shown that the Mie phase function characterizes better than the Henyey-Greenstein (H-G) phase function in MC calculation. Next, we compare the measurement spectra with those obtained by modeling as single-peak, conventional modelling for particle size distribution, and for double-peak particle size distribution. The single-peak modeling is found to cause considerable error for the tissue phantom with double-peak particle size distribution, which seems to simulate a biological tissue. We suggest that if one simulates the particle size distribution of a biological tissue by conventional modeling, the accuracy of estimation will be lower. [ABSTRACT FROM AUTHOR]

The p53 tumor suppressor gene can induce either apoptosis or a permanent growth arrest (also termed senescence) phenotype in response to cellular stresses. We show that the increase in intracellular reactive oxygen species (ROS) associated with the magnitude of p53 protein expression correlated with the induction of either senescence or apoptosis in both normal and cancer cells. ROS inhibitors ameliorated both p53dependent cell fates, implicating ROS accumulation as an effector in each case. The absence of Bax or PUMA strongly inhibited both p53-induced apoptosis and ROS increase, indicating an important role these p53 targets affecting mitochondrial function genes in p53-mediated ROS accumulation. Moreover, physiological p53 levels in combination with an exogenous ROS source were able to convert a p53 senescence response into apoptosis. All of these findings establish a critical role of ROS accumulation and mitochondrial function in p53-dependent cell fates and show that other ROS inducers can collaborate with p53 to influence these fate decisions. Thus, our studies imply that therapeutic agents that generate ROS are more likely to be toxic for normal cells than p53-negative tumor cells and provide a rationale for identifying therapeutic agents that do not complement p53 in ROS generation to ameliorate the cytotoxic side effects in normal cells. [ABSTRACT FROM AUTHOR]

We directly sequenced PCR fragments amplified from a porcine thyroid cDNA library with various synthetic primers based on the nucleotide sequence of bovine thyrotropin receptor (bTSHR) cDNA. A nucleotide sequence of 2410 bp was determined and its deduced amino acid sequence contained an open reading frame coding 764 amino acids, which showed 91.8% and 89.5% similarity to bTSHR and human TSH receptor, respectively. A hydrophobicity plot of the porcine protein suggested that it had a putative signal peptide and seven transmembrane domains. Chinese hamster ovary cells stably transfected with the cDNA could be specifically bound to bovine TSH (bTSH) and increased the intracellular cAMP level in response to bTSH and Graves' disease patients' sera stimulation. Clin Chem Lab Med 2003; 41(6):796-803. [ABSTRACT FROM AUTHOR]

Binding specificity between fibroblast growth factors (FGFs) and their receptors (FGFRs) is essential for mammalian development and is regulated primarily by two alternatively spliced exons, IIIb ("b") and IIIc ("c"), that encode the second half of Ig-like domain 3 (D3) of FGFRs. FGF7 and FGF10 activate only the b isoform of FGFR2 (FGFR2b). Here, we report the crystal structure of the ligand-binding portion of FGFR2b bound to FGF10. Unique contacts between divergent regions in FGF10 and two b-specific loops in D3 reveal the structural basis by which alternative splicing provides FGF10-FGFR2b specificity. Structure-based mutagenesis of FGF10 confirms the importance of the observed contacts for FGF10 biological activity. Interestingly, FGF10 binding induces a previously unobserved rotation of receptor Ig domain 2 (D2) to introduce specific contacts with FGF10. Hence, both D2 and D3 of FGFR2b contribute to the exceptional specificity between FGF10 and FGFR2b. We propose that ligand-induced conformational change in FGFRs may also play an important role in determining specificity for other FGF-FGFR complexes. [ABSTRACT FROM AUTHOR]

Background: Tartrate-resistant acid phosphatase (TRAP) is known as a marker of bone resorption. The purpose of this study was the development of a sensitive and specific immunoassay for TRAP. Methods: We have developed two types of immunoassays, enzyme-linked immunosorbent assay (ELISA) and immunoselective enzyme immunoassay (ISEA) using monoclonal antibodies to recombinant TRAP, for determination of TRAP in human serum. To evaluate assay performance, recovery and dilution tests were performed. Further, we determined serum TRAP levels of patients with secondary hyperparathyroidism at different pH conditions. Results: The detected ranges of ELISA and ISEA were between 0.08 and 5 μg/l and between 0.063 and 4 U/l. Different concentrations of TRAP added were recovered on average at 98.0% in ELISA and 102.9% in ISEA. In the serial dilution test, serum TRAP levels were on average at 101.6% and 109.6% of the expected values in ELISA and ISEA, respectively. The serum TRAP levels of patients with secondary hyperparathyroidism were significantly higher than those of normal controls in ELISA and ISEA. Similar TRAP levels were obtained in the conditions at pH 5.5 and 6.1 in ISEA. Conclusion: The present findings suggest that our assay methods are applicable for clinical tests, and strengthen the idea that serum TRAP is useful as a marker for bone resorption. [Copyright &y& Elsevier]

Objective assessment of gastrointestinal mucosal color is extremely important in the endoscopic diagnosis of digestive tract disease. In this paper, we propose a method to clarify the spectral characteristics of gastric and colon cancer. A large number of spectral reflectance data of mucous membrane are measured by the endoscopic spectroscopy system (ESS) in the National Cancer Center Hospital East, Kashiwa, Japan and the Department of Internal Medicine, SelfDefense Force Center Hospital, Tokyo, Japan. We assume that early cancer appears primarily in the spectral data of short wavelength, because it is usually present in a superficial cell where short wavelength light is scattered more strongly than long wavelength light. To identify the features in the short wavelength components, the spectral reflectance was divided by the reflectance of a long wavelength. We investigated the possibility of distinguishing early cancer from normal spectral data through statistical analysis, employing the projection axis as the mean difference between them. Early cancer and normal spectral data were projected on the projection axis, and the Student's T-test was applied to evaluate the mean of the distribution between these data. [ABSTRACT FROM AUTHOR]

The cyclin-dependent kinase (CDK) inhibitor p21Waf1/CiP1/Sdi1 was identified initially as a gene induced in senescent cells and itself has been shown to cause permanent growth arrest/senescence. Reactive oxygen species (ROS), a byproduct of oxidative processes, can also induce an irreversible growth arrest similar to senescence. Here we show that p21 increased intracellular levels of ROS both in normal fibroblasts and in p53-negative cancer cells. N-acetyl-L-cysteine, an ROS inhibitor, rescued p21-induced senescence, showing that ROS elevation is necessary for induction of the permanent growth arrest phenotype. p16Ink4a, a CDK4- and CDK6-specific inhibitor, failed to increase ROS levels, and cell cycle arrest induced by p16 was reversible following its down-regulation, demonstrating the specificity of this p21 effect. A p21 mutant that tacked the ability to bind proliferating cell nuclear antigen (PCNA) retained the ability to induce both ROS and permanent growth arrest. All of these findings establish that p21 mediates senescence by a mechanism involving ROS accumulation which does not require either its PCNA binding or the CDK inhibitory functions shared with p16. [ABSTRACT FROM AUTHOR]

We have shown previously that wild type p53 can rapidly induce replicative senescence in EJ human bladder carcinoma cells lacking functional p53. A major effector of p53 functions is p21Waf1/Cip1/Sdi1, a potent cyclin-dependent kinase inhibitor. p21Waf1/Cip1/Sdi1 has been shown to be involved in both p53 dependent and independent control of cell proliferation, differentiation and death. To directly investigate the effects of p21Waf1/Cip1/Sid1 in the p53 response observed in EJ tumor cells, we established p21Waf1/Cip1/Sdi1 inducible lines using the tetracycline-regulatable vector system. p21Waf1/Cip1/Sdi1 induction caused irreversible cell cycle arrest in both G1 and G2/M, and diminished Cdk2 kinase activity. In addition, p21Waf1/Cip1/Sdi1 induction led to morphological alterations characteristic of cells undergoing replicative senescence with morphological, biochemical and ultrastructural markers of the senescent phenotype. Furthermore, sustained p21Waf1/Cip1/Sdi1 induction sensitized EJ cells to apoptotic cell death induced by mitomycin C, a cross-linking DNA damaging agent. These findings support the function of p21Waf1/Cip1/Sdi1 as an inducer of replicative senescence and a major mediator of this phenomenon in response to p53. Moreover, our results imply that therapeutic intervention in human cancers might be aimed at sustained elevation of p21Waf1/Cip1/Sdi1 expression. [ABSTRACT FROM AUTHOR]

Quantum dot solar cells consisting of a sub-10-nm highly ordered and dense 2-dimensional (2D) array of Si nanodisks (Si-NDs) as a quantum dot superlattice with a SiC interlayer are achieved. The Si-NDs are fabricated with an original top-down process involving a 2D array of bio-templates with a 4.5-nm-diameter iron core and damage-free neutral beam etching (Si-ND diameter: 6.4 nm). The Si-ND array has a high optical absorption coefficient due to miniband formation. As a result, the cells achieve open-circuit voltage of 0.556 V, short-circuit current density of 31.3 mA/cm2, a 72% fill factor, and 12.6% conversion efficiency. [ABSTRACT FROM AUTHOR]

Considering the long lifespan of the liver fluke Opisthorchis viverrini , human mobility from prevalent regions to other neighboring areas has the possibility to disperse carriers and complicate the opisthorchiasis problem. To evaluate this, mass screening of the fluke infection was conducted in nine communities of lower Northern Thailand, combined with a questionnaire survey to distinguish the participant’s origin. The liver fluke infection was found in 70 individuals (7.2%) of the examined 971 stool samples from seven communities, with light intensity providing small numbers of eggs in the examined stool. Prevalence in the positive communities varied from 2.1% to 28.7%. As a result of generalized linear mixed models fitting, regional origin and raw-fish eating habits were stably selected as variables affecting the parasite infection while occupation and educational background were secondary ones. Majority of the infected cases (64.3%) were found from the immigrants of northeastern Thailand (the fluke prevalent region), providing 2.28–2.42 times higher infectious risk on average against the local residents. Daily consumption of raw fish averaged a 3.12–3.60 times higher risk compared to those with no raw-fish eating habit. Our findings suggest that people’s origin and moving history deserve further attentions in health promotion programs including education for safe eating. [ABSTRACT FROM AUTHOR]

Toxoplasmosis is a cosmopolitan protozoan zoonosis caused by Toxoplasma gondii infamous for inducing severe clinical manifestations in humans. Although the disease affects at least one billion people worldwide, it is neglected in many countries including developed ones. In literature, the epidemiological data documenting the actual incidence of the disease in humans and domestic animals from Japan are limited and importantly many earlier papers on T. gondii infections were published in Japanese and a considerable part is not available online. Herein, we review the current summary about the epidemiological situation of T. gondii infection in Japan and the potential associated risk factors in humans and animals as well as the different T. gondii genotypes isolated in Japan. Several T. gondii isolates have been identified among cats (TgCatJpTy1/k-3, TgCatJpGi1/TaJ, TgCatJpObi1 and TgCatJpOk1–4) and goats (TgGoatJpOk1–13). This literature review underscores the need for a nationwide investigation of T. gondii infection in Japanese people and assessment of the socioeconomic impact of the disease burden. Furthermore, epidemiological studies in domestic and wild animals and estimation of degree of contamination of soil or water with T. gondii oocysts are needed, for a better understanding of the scope of this public health concern. [ABSTRACT FROM AUTHOR]

Abstract: Within the envelop-function framework, we developed the finite element method to calculate the minibands in the realist Silicon nanocrystal array. This method clearly reveals the miniband formation and accurately calculates the dispersion relationship. In the simple 1D array, the deduced miniband structure matches well with the analytic Kronig–Penney method. More importantly, it can better simulate the 2D and 3D nanocrystal array, which avoids approximations of the quantum cubic box and the independent periodic potential of the multi-dimension Kronig–Penney method. Further, this model is utilized to calculate miniband structure of realistic 2D-array Silicon nanodisk array for guiding quantum dot solar cell design. [Copyright &y& Elsevier]

We have fabricated GaAs nanodisk (ND) structures by using a combination of neutral beam etching process and atomic hydrogen-assisted molecular beam epitaxy regrowth. We have observed clear photoluminescence (PL) emissions from GaAs NDs. The peak energy showed a blueshift due to the quantum confinement in three spatial dimensions, and it agreed with the theoretically estimated transition energy. The PL results also showed that the cap-layer disks act as radiative recombination centers. We have confirmed that the PL emission originates from the GaAs NDs, and our approach is effective for the fabrication of high quality ND structures. [ABSTRACT FROM AUTHOR]

We study picosecond transient photoluminescence (PL) in Si-nanodisk (Si-ND) arrays fabricated using bio-nano-templates. The PL time profiles show multi-exponential decaying kinetics depending on the disk density. We attribute the fastest decaying component with a decay time of 40 ps observed only in the high-density Si-ND array to the electron transfer among the Si-NDs. [ABSTRACT FROM AUTHOR]

The aim of the present study using near-infrared spectroscopy (NIRS) is to evaluate the correlation of cerebral (parieto-temporal lobe) hemoglobin changes and vertiginous sensation during unilateral caloric stimulation. During the hot water (44° C) stimulus, cerebral hemoglobin was increased bilaterally, but it was dominant ipsilaterally. During the unilateral cold water (30° C) stimulus, cerebral hemoglobin was decreased on both sides, especially on the ipsilateral side. Vertigious sensation was strong in cases with marked left-right difference of cerebral hemoglobin changes. The usefulness of NIRS to investigate the relationship between peripheral vestibular organ and vestibular cortex was verified. [ABSTRACT FROM AUTHOR]

Conclusions. A lengthy alteration of gravity direction produced different effects on the intrinsic horizontal and vertical optokinetic oculomotor systems. Objective. To examine both optokinetic nystagmus (OKN) and optokinetic after-nystagmus (OKAN) in a 6 h 6° head-down bedrest study, in which the subjects were kept lying under simulated micro-gravity conditions. Subjects and methods. In six normal healthy adults, we repeatedly (five times) and comparatively studied OKN and OKAN evoked by horizontal and vertical stimuli. Stage 1 was an upright sitting position. During the 6 h bedrest condition, we studied OKN and OKAN in 90° recumbent lateral positions (stages 2, 3, and 4). In stage 5 the subject returned to an upright position. Results. We confirmed that the change in gravity direction had various effects on the condition of OKN and OKAN. Also, we found that it took more than 3 h to reach a desirable level of systemic adaptive modification to the unique environmental condition. We considered that the early change was basically due to the changes in sensory inputs through the otolith organs, and the latter changes represented the adaptive process of the spatial orientation system. During the tilt, the occurrence rates of both horizontal and vertical OKANs were decreased; however, the conditions of these changes were different. [ABSTRACT FROM AUTHOR]

Inosine 5′-monophosphate dehydrogenase (IMPDH) is an essential enzyme for the production of guanine nucleotides. Disruption of IMPDH activity has been explored as a therapeutic strategy for numerous purposes, such as for anticancer, immunosuppression, antiviral, and antimicrobial therapy. In the present study, we established a luciferase-based high-throughput screening system to identify IMPDH inhibitors from our chemical library of known bioactive small molecules. The screening of 1400 compounds resulted in the discovery of three irreversible inhibitors: disulfiram, bronopol, and ebselen. Each compound has a distinct chemical moiety that differs from other reported IMPDH inhibitors. Further evaluation revealed that these compounds are potent inhibitors of IMPDHs with kon values of 0.7 × 104 to 9.3 × 104 M−1·s−1. Both disulfiram and bronopol exerted similar degree of inhibition to protozoan and mammalian IMPDHs. Ebselen showed an intriguing difference in mode of inhibition for different IMPDHs, with reversible and irreversible inhibition to each Cryptosporidium parvum IMPDH and human IMPDH type II, respectively. In the preliminary efficacy experiment against cryptosporidiosis in severe combined immunodeficiency (SCID) mouse, a decrease in the number of oocyst shed was observed upon the oral administration of disulfiram and bronopol, providing an early clinical proof-of-concept for further utilization of these compounds as IMPDH inhibitors. [ABSTRACT FROM AUTHOR]

Oocyst stage of Toxoplasma gondii is characterized by a durable wall that confers a strong protection to this protozoan parasite in face of harsh environmental conditions. Thus, it is considered the key for transmission of T. gondii. Analysis of oocyst wall composition is mandatory therefore; the aim of this study was to identify novel T. gondii oocyst wall proteins and test their use in detection of these oocysts in environmental samples. Five candidates of novel T. gondii oocyst wall proteins (TgOWPs) were identified and named TgOWP8 through TgOWP12. Recombinant protein of TgOWP8 was expressed in E. coli using glutathione S-transferase as fusion protein. Polyclonal antibody was produced and validated by indirect immunofluorescence antibody assay (IFA). For detection by IFA, we used different methods for fixation and permeabilization of oocysts to improve the antigen-antibody detection. Specificity to wall of T. gondii oocyst was confirmed and revealed absence of cross reactivity with bradyzoite cyst wall and tachyzoites. Although some TgOWPs were identified previously, our study represents a continuation of molecular investigations of oocyst wall proteins as an essential structure for the longevity and infectivity of this stage and also provided new trial to improve T. gondii oocysts detection. [ABSTRACT FROM AUTHOR]

In the asexual stages, Toxoplasma gondii stage converts between acute phase rapidly replicating tachyzoites and chronic phase slowly dividing bradyzoites. Correspondingly, T. gondii differentially expresses two distinct genes and isoforms of the lactate dehydrogenase enzyme, expressing LDH1 exclusively in the tachyzoite stage and LDH2 preferentially in the bradyzoite stage. LDH catalyzes the interconversion of pyruvate and lactate in anaerobic growth conditions and is utilized for energy supply, however, the precise role of LDH1 and LDH2 in parasite biology in the asexual stages is still unclear. Here, we investigated the biological role of LDH1 and LDH2 in the asexual stages, and the vaccine strain potential of deletion mutants lacking LDH1, LDH2, or both genes (Δldh1, Δldh2 and Δldh1/2). Deletion of LDH1 reduced acute parasite virulence, impaired bradyzoite differentiation in vitro, and markedly reduced chronic stage cyst burdens in vivo. In contrast, deletion of LDH2 impaired chronic stage cyst burdens without affecting virulence or bradyzoite differentiation. Deletion of both LDH1 and LDH2 induced a more severe defect in chronic stage cyst burdens. These LDH mutant phenotypes were not associated with any growth defect. Vaccination of mice with a low dose of mutants deleted for LDH elicited effective protective immunity to lethal challenge infection, demonstrating the vaccine potential of LDH deletion mutants. These results suggest that lactate dehydrogenase in T. gondii controls virulence, bradyzoite differentiation, and chronic infection and reveals the potential of LDH mutants as vaccine strains. [ABSTRACT FROM AUTHOR]

Cats are the only definitive hosts of Toxoplasma gondii and constitute an essential source of infection to all warm blooded animals and humans. Diagnosis of T. gondii infection in cats is fundamental for proper management and control of infection in humans and animals. In the current study, we have evaluated the diagnostic performance of tachyzoite lysate antigen (TLA) and different T. gondii recombinant antigens including surface antigen 2 (SAG2), dense granule proteins 2, 6, 7, 15 (GRA2, GRA6, GRA7, GRA15) and microneme 10 protein (MIC10) in immunoglobulin G enzyme linked-immunosorbent assay (IgG ELISA) using cat serum samples, with reference to latex agglutination test (LAT). Remarkably, TLA showed better performance than other recombinant antigens in IgG ELISAs as compared to LAT, with concordance and Kappa values of 94.27% and 0.93, respectively. Furthermore, to improve the reactivity of the recombinant antigens, we have developed IgG ELISAs using different combinations with these recombinant antigens. Strikingly, a combination of SAG2 and GRAs has relatively similar performance as TLA evidenced by concordance and Kappa values of 94.27% and 0.81, respectively. The developed ELISA with a combination of recombinant antigens can be used as a promising diagnostic tool for routine testing of T. gondii infection and mass screening in cats. The major advantages of this assay are the high sensitivity and specificity, lower cost, safer production and easiness of standardization in various laboratories worldwide. [ABSTRACT FROM AUTHOR]

The one-humped camel (Camelus dromedarius) or dromedary is an economically important domestic animal. However, infectious diseases, including those caused by vector-borne hemopathogens, frequently compromise the health and production of camels. In this study, we examined infections caused by Babesia , Theileria , Trypanosoma , and Anaplasma species in camels in Egypt. We analyzed blood DNA samples from 148 camels reared in six Egyptian governorates (Giza, Asyut, Sohag, Qena, Luxor, and the Red Sea) using pathogen-specific Polymerase Chain Reaction (PCR) assays. Our results indicated that 29 (19.6%), 22 (14.9%), 1 (0.7%), 2 (1.4%), 1 (0.7%), 2 (1.4%), and 28 (18.9%) of the surveyed animals were infected with Babesia bovis , B. bigemina , Babesia sp. Mymensingh, Theileria sp. Yokoyama, Theileria equi , Trypanosoma evansi , and Anaplasma marginale , respectively. We found that a total of 68 (45.9%) animals were infected with at least one of the detected hemopathogens. Sequencing analyses of PCR amplicons confirmed our diagnostic results. This study is the first to report Theileria sp. Yokoyama and Babesia sp. Mymensingh in Egypt. This is also the first report of infection with these two species in one-humped camel. In conclusion, this study found that camels in Egypt are infected with several vector-borne hemopathogens, including novel parasite species. [Display omitted] • We surveyed camels in six Egyptian governorates for hemopathogens using PCR assays • We detected several species of Babesia , Theileria , Trypanosoma , and Anaplasma • We report Babesia sp. Mymensingh in dromedary and in Egypt for the first time • We report Theileria sp. Yokoyama in dromedary and in Egypt for the first time [ABSTRACT FROM AUTHOR]

Goat farming is important for the livelihood of millions of rural people because it contributes to food security and creation of assets. However, infection of goats with Toxoplasma gondii could be a source of parasite transmission to humans. The information on T. gondii infection of goat was not reported yet in Myanmar. A total of 119 goat serum samples were collected from three cities in the central region of Myanmar for T. gondii antibody survey. With the occurrence value obtained in this first study, a second one, more complete, with larger number (162) of animals and properties, was carried out and the risk factors and prevalence were determined. In both studies the samples were analyzed by the LAT. Of these, 32 (11.4%) samples were showed to be positive. The infection was associated with the presence of cats at the farm (odds ratio [OR] = 4.66, 95% confidential interval [CI] = 1.03–21.06), farming with different animal species (sheep, cattle, and pigs) (OR = 4.33, 95% CI = 1.57–11.94), and farming without good management practices (OR = 0.23, 95% CI = 0.06–0.83). This is the first T. gondii prevalence study in goats in the country. [ABSTRACT FROM AUTHOR]

Background: The glyoxalase pathway, which includes two enzymes, glyoxalase 1 and 2 (Glo1 and Glo2), is a ubiquitous cellular system responsible for the removal of cytotoxic methylglyoxal produced during glycolysis. Protozoan parasites, including Toxoplasma gondii (T. gondii) tachyzoites, produce methylglyoxal because of increased glycolytic fluxes. A Glo1 inhibitor such as curcumin could be considered a drug candidate for anti-protozoan, anti-inflammatory, and anti-cancer therapy. Methods: The T. gondii Glo1 gene (TgGlo1) was cloned and the recombinant protein was produced. Enzyme kinetics of TgGlo1 and five mutants were evaluated by adding methylglyoxal and glutathione to a reaction mixture. Finally, the inhibitory effects of various concentrations of curcumin on recombinant TgGlo1 were evaluated using in vitro cultures of T. gondii. Results: Active recombinant TgGlo1 was successfully produced and the active sites (E166 and E251) of TgGlo1 were verified by point mutagenesis. Curcumin at the tested doses inhibited the enzymatic activity of recombinant TgGlo1 as well as the parasitic propagation of in vitro-cultured T. gondii. The Ki and IC50 were 12.9 ± 0.5 μM and 38.3 ± 0.9 μM, respectively. Conclusion: The inhibitory effect of curcumin on the enzymatic activity of TgGlo1 and parasitic propagation of T. gondii could be explored in the potential development of a potent drug for the treatment of toxoplasmosis. However, considering the fact that curcumin is known to have many effects on other molecules in the micromolar range, further elucidation of curcumin's direct inhibition of the glyoxalase system of T. gondii will be needed. [ABSTRACT FROM AUTHOR]

Parasites of the phylum Apicomplexa are highly successful pathogens of humans and animals worldwide. As obligate intracellular parasites, they have significant energy requirements for invasion and gliding motility that are supplied by various metabolic pathways. Aldolases have emerged as key enzymes involved in these pathways, and all apicomplexans express one or both of fructose 1,6-bisphosphate (F16BP) aldolase and 2-deoxyribose 5-phosphate (dR5P) aldolase (DERA). Intriguingly, Toxoplasma gondii , a highly successful apicomplexan parasite, expresses F16BP aldolase ( Tg ALD1), d5RP aldolase ( Tg DERA), and a divergent dR5P aldolase-like protein ( Tg DPA) exclusively in the latent bradyzoite stage. While the importance of Tg ALD1 in glycolysis is well established and Tg DERA is also likely to be involved in parasite metabolism, the detailed function of Tg DPA remains elusive. To gain mechanistic insight into the function of different T. gondii aldolases, we first determined the crystal structures of Tg ALD1 and Tg DPA. Structural analysis revealed that both aldolases adopt a TIM barrel fold accessorized with divergent secondary structure elements. Structural comparison of Tg ALD1 and Tg DPA with members of their respective enzyme families revealed that, while the active-site residues are conserved in Tg ALD1, key catalytic residues are absent in Tg DPA. Consistent with this observation, biochemical assays showed that, while Tg ALD1 was active on F16BP, Tg DPA was inactive on dR5P. Intriguingly, both aldolases are competent to bind polymerized actin in vitro . Altogether, structural and biochemical analyses of T. gondii aldolase and aldolase-like proteins reveal diverse functionalization of the classic TIM barrel aldolase fold. [ABSTRACT FROM AUTHOR]

Abstract: The authors study surface/interface-related optical properties in Si nanodisks (NDs) fabricated by neutral-beam etching using bio-templates. Photoluminescence (PL) spectra and the transient properties are compared between different barrier materials of SiO2 and SiC. The PL spectral shape depends on the barrier material, indicating effects of oxide formation and/or oxygen atoms on the surface of the Si ND. The transient PL shows nanosecond-scale transition of carriers in surface-related quantum states in the ND. Temperature dependences of the PL intensity show that the activation energy responsible for the electron escape from the Si-ND at near room temperature in the case of SiC barrier agrees well with the conduction band offset, whereas that in the case of SiO2 barrier is significantly lower than the expected offset. The latter discrepancy suggests that the electronic band structure at the interface of Si-ND/SiO2 can be largely affected by dielectric screening due to oxygen atoms in the SiO2. [Copyright &y& Elsevier]

Highlights: [•] B. gibsoni aldolase forms a complex with B. gibsoni TRAP and B. gibsoni actin. [•] The complex is likely to regulate an actin polymerization. [•] Parasite growth is inhibited by treatment with cytochalasin D, an inhibitor of an actin polymerization. [•] Actin dynamics seem to be essential for erythrocyte invasion by B. gibsoni. [Copyright &y& Elsevier]

Highlights: [•] We identify a novel dense granule protein, GRA22, in Toxoplasma gondii. [•] We generate GRA22 knockout parasite strain. [•] GRA22 knockout parasite strain shows early egress phenotype. [Copyright &y& Elsevier]

Abstract: The DnaK-tetratricopeptide repeat (DnaK-TPR) gene (ToxoDB ID, TGME49_002020) is expressed predominantly at the bradyzoite stage. DnaK-TPR protein has a heat shock protein (DnaK) and tetratricopeptide repeat (TPR) domains with amino acid sequence similarity to the counterparts of other organisms (40.2–43.7% to DnaK domain and 41.1–66.0% to TPR domain). These findings allowed us to infer that DnaK-TPR protein is important in the tachyzoite-to-bradyzoite development or maintenance of cyst structure although the function of this gene is still unknown. An immunofluorescence assay (IFA) revealed that DnaK-TPR protein was expressed in Toxoplasma gondii-encysted and in vitro-induced bradyzoites and distributed in the whole part of parasite cells. We conducted yeast two-hybrid screening to identify proteins interacting with DnaK-TPR protein, and demonstrated that DnaK-TPR protein interacts with p23 co-chaperone protein (Tgp23). It was expected that DnaK-TPR protein would have a function as a molecular chaperon in bradyzoite cells associated with Tgp23. Possible mechanisms for this gene are discussed. [Copyright &y& Elsevier]

Abstract: The Toxoplasma gondii deoxyribose phosphate aldolase-like (TgDPA) gene is expressed predominantly in bradyzoites. This finding allowed us to infer that TgDPA is important in the tachyzoite-to-bradyzoite development or maintenance of cyst structure although the function of this gene is still unknown. We conducted yeast two-hybrid screening to identify proteins interacting with TgDPA, and the actin depolymerizing factor (TgADF) gene was obtained. Co-immunoprecipitation and a GST pull-down assay demonstrated that TgDPA interacts with TgADF. To reveal the significance of the protein–protein interaction between TgDPA and TgADF, actin polymerization and disassembly kinetics were examined. Addition of GST-TgDPA to TgADF lowered the extent of actin polymerization and enhanced the filamentous actin disassembly. These results demonstrated that this is the novel protein–protein interaction in T. gondii, and that TgDPA can enhance the activity of TgADF. This phenomenon might play an important role in T. gondii bradyzoites by affecting the actin turnover. [Copyright &y& Elsevier]

Abstract: Toxoplasma gondii is an obligate intracellular protozoan parasite that invades a wide range of host cells. The parasite releases a large variety of proteins from a secretory organelle, microneme, and the secretion is essential for the parasite invasion. We cloned a secreted protein with an altered thrombospondin repeat of Toxoplasma gondii (TgSPATR), which was the homologue of Plasmodium SPATRs. Immunofluorescence double staining experiment revealed that TgSPATR was co-localized with a microneme protein, MIC2, and immuno-electron microscopic (IEM) analysis detected TgSPATR in the microneme-like structure. TgSPATR secretion was induced by ethanol, while an intracellular Ca2+ chelator, 1,2-bis(o-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid, tetraacetoxymethyl ester (BAPTA-AM), suppressed the ethanol-induced secretion, suggesting the secretion was Ca2+-dependent, similarly to known microneme proteins. Furthermore, TgSPATR, existed on outer surface of the parasites, was detected by incomplete membrane permeabilization by saponin and immunofluorescent antibody test (IFAT). Both TgSPATR and MIC2 were detected on outer surface of extracellular parasites, but not of intracellular single parasites, suggesting they were similarly secreted during early stages of parasite invasion. Therefore, TgSPATR is probably new member of microneme protein and maybe involved in parasite invasion. [Copyright &y& Elsevier]

Abstract: Toxoplasma gondii undergoes stage conversion from tachyzoites to bradyzoites in intermediate hosts. There have been many reports on bradyzoite-specific genes which are thought to be involved in stage conversion. Here, we described a novel T. gondii deoxyribose phosphate aldolase-like gene (TgDPA) expressing predominantly in bradyzoites. The TgDPA gene encodes 286 amino acids having a predicted molecular weight of 31kDa. Sequence analysis revealed that TgDPA had a deoxyribose phosphate aldolase (DeoC) domain with about 30% homology with its Escherichia coli counterpart. RT- and quantitative PCR analyses showed that the TgDPA gene was more expressed in bradyzoites and that its expression gradually increased during in vitro tachyzoite-to-bradyzoite stage conversion. A polyclonal antibody against recombinant TgDPA protein was raised in rabbits, and immunofluorescent analysis demonstrated that TgDPA was expressed in bradyzoites in vivo and in vitro. These findings indicate that the TgDPA gene is a new bradyzoite-specific marker and might play a role in bradyzoites. [Copyright &y& Elsevier]

Abstract: We developed a sandwich ELISA for the detection of circulating Toxoplasma gondii MIC10 antigens. In T. gondii culture supernatant, MIC10 was detected in a growth dependent manner. Mice were infected with a lethal dose of either a virulent RH strain, an avirulent Beverley strain or a sub-lethal dose of a PLK strain of T. gondii. MIC10 appeared 2 days after infection and increased gradually in the sera of RH-infected mice. A detectable but significantly lower amount of MIC10 was observed in the sera of mice infected intraperitoneally with Beverley tachyzoites. In contrast, the MIC10 antigen in mice sera following oral infection with Beverley cysts was below detectable levels during the course of the experiment. In sera of PLK-infected mice, MIC10 was predominantly observed between late acute and early chronic phase. Our data show that the kinetics of circulating MIC10 differs depending on the strain and route of infection. [Copyright &y& Elsevier]

Abstract: A combination of antigenic regions of microneme proteins have been previously reported as being protective against chronic toxoplasmosis. In this work, we evaluated immune responses induced by immunizing BALB/c and C57BL/6 mice intradermally with plasmid DNA encoding the protein sequences of Toxoplasma gondii AMA1, MIC2, M2AP and BAG1. Mice immunized with the AMA1 gene developed high levels of serum IgG2a and c antibodies as well as cellular immune responses associated with IFN-γ synthesis suggesting a modulated Th1 type of response. Immunization with the AMA1 gene resulted in a partial but significant protection against the acute phase of toxoplasmosis compared to MIC2, M2AP and BAG1 genes. Therefore, the AMA1 gene appears to generate a strong specific immune response and also provides effective protection against toxoplasmosis more than the MIC2, M2AP and BAG1 genes. [Copyright &y& Elsevier]

The Svalbard archipelago in arctic Norway receives considerable semivolatile organic contaminant (SOC) inputs from the atmosphere. To measure the history of net Soc accumulation there, we analyzed the upper 40 m of an ice core from Austfonna, the largest ice cap in Eurasia, for several legacy organochlorine (OC) compounds and current- use pesticides (CUPs) including organophosphorus (OP), triazine, dinitroaniline, and chioroacetamide compounds. Five OP compounds (chlorpyrifos, terbufos, diazinon, methyl parathion, and fenitrothion), two OCs (methoxychlor and dieldrin), and metolachlor–an herbicide–had historical profiles in the core. The highest OC concentration observed was aldrin (69.0 ng L-1) in the surface sample (1992-1998). The most concentrated OP was dimethoate (87.0 ng L-1) between 1986 and 1992. The surface sample also had highest concentrations of pendimethalin (herbicide, 18.6 ng L-1) and flutriafol, the lone observed fungicide (9.6 ng L-1). The apparent atmospheric persistence of CUPs likely results from little or no oxidation by OH during the dark polar winter and in spring. Long-range atmospheric pesticide transport to Svalbard from Eurasia is influenced by the positive state of the North Atlantic Oscillation Index since 1980 and also by occasional fast-moving summer air masses from northern Eurasian croplands. [ABSTRACT FROM AUTHOR]

Ice cores from the relatively low-lying ice caps in Svalbard have not been widely exploited in climatic studies owing to uncertainties about the effect of meltwater percolation. However, results from two new Svalbard ice cores, at Lomonosovfonna and Austfonna, have shown that with careful site selection, high-resolution sampling and multiple chemical analyses it is possible to recover ice cores from which part of the annual signals are preserved, despite the considerable meltwater percolation. The new Svalbard ice cores are positioned in different parts of Svalbard and cover the past 800 years. In this paper we focus on the last 400 years. The δ18O signals from the cores are qualitatively similar over most of the twentieth century, suggesting that they record the same atmospheric signal. Prior to AD 1920, the Austfonna ice core exhibits more negative δ18O values than Lomonosovfonna, although there are intermittent decadal-scale periods throughout the record with similar values. We suggest that the differences reflect the effect of the inversion layer during the winter. The pattern in the δ18O records is similar to the Longyearbyen air-temperature record, but on an annual level the correlation is low. The Austfonna record correlates well with the temperature record from the more distant and southwesterly located Jan Mayen. A comparison of the ice-core and sea-ice records from this period suggests that sea-ice extent and Austfonna δ18O are related over the past 400 years. This may reflect the position of the storm tracks and their direct influence on the relatively low-altitude Austfonna. Lomonosovfonna may be less sensitive to such changes and primarily record free atmospheric changes instead of variations in sea-ice extent, the latter is probably a result of its higher elevation. [ABSTRACT FROM AUTHOR]

Two competing models for fibroblast growth factor (FGF) receptor (FGFR) dimerization have recently emerged based on ternary FGF-FGFR-heparin crystal structures. In the symmetric two-end model, heparin promotes dimerization of two FGF-FGFR complexes by stabilizing bivalent interactions of the ligand and receptor through primary and secondary sites and by stabilizing direct receptor-receptor contacts. In the asymmetric model, there are no protein-protein contacts between the two FGF-FGFR complexes, which are bridged solely by heparin. To identify the correct mode of FGFR dimerization, we abolished interactions at the secondary ligand-receptor interaction site, which are observed only in the symmetric two-end model, using site-directed mutagenesis. Cellular studies and real-time binding assays, as well as matrix-assisted laser desorption ionization—time of flight analysis, demonstrate that loss of secondary ligand-receptor interactions results in diminished FGFR activation due to decreased dimerization without affecting FGF-FGFR binding. Additionally, structural and biochemical analysis of an activating FGFR2 mutation resulting in Pfeiffer syndrome confirms the physiological significance of receptor-receptor contacts in the symmetric two-end model and provides a novel mechanism for FGFR gain of function in human skeletal disorders. Taken together, the data validate the symmetric two-end model of FGFR dimerization and argue against the asymmetric model of FGFR dimerization. [ABSTRACT FROM AUTHOR]

Ice cores from the relatively low-lying ice caps in Svalbard have not been widely exploited in climatic and environmental studies due to uncertainties about the effect of melt water percolation. However, results from two recent Svalbard ice cores, at Lomonosovfonna (1250 m asl) and Austfonna (750 m asl), have shown that with careful site selection, high-resolution sampling and multiple chemical analyses, it is possible to recover ice cores with partly preserved annual signals. These cores are estimated to cover at least the past 600 years and have been dated using a combination of known reference horizons and glacial modeling. The δ18O data from both Lomonosovfonna and Austfonna ice cores suggest that the 20th century was the warmest during the past 600 years. A comparison of the ice core and sea ice records from this period suggests that sea ice extent and Austfonna δ18O are linked over the past 400 years. This may reflect the position of the storm tracks and their direct influence on the relatively low altitude Austfonna. Lomonosovfonna may be less sensitive to such changes and primarily record atmospheric changes due to its higher elevation. The anthropogenic influence on Svalbard environment is illustrated by increased levels of non-sea-salt sulphate, nitrate, acidity, fly-ash and organic contaminants particularly during the second half of 1900s. Decreased concentrations of some components in recent decades most likely reflect emission and use restrictions. However, some current-use organic pesticide compounds show growing concentrations in near surface layers. [Copyright &y& Elsevier]

Fibroblast growth factor 10 is a novel member of the fibroblast growth factor family, which is involved in morphogenesis and epithelial proliferation. It is highly homologous to the keratinocyte growth factor (or fibroblast growth factor 7), a key mediator of keratinocyte growth and differentiation. Both fibroblast growth factor 10 and keratinocyte growth factor bind with high affinity to the tyrosine kinase keratinocyte growth factor receptor. Here we analyzed the effect of fibroblast growth factor 10 on primary cultures of human keratinocytes, grown in chemically defined medium, and we compared the proliferative and differentiative cell responses to fibroblast growth factor 10 with those induced by keratinocyte growth factor and epidermal growth factor. Cell counting, 5-bromo-2′-deoxyuridine incorporation, and western blot analysis showed that fibroblast growth factor 10, similarly to keratinocyte growth factor, not only is a potent mitogen for human keratinocytes, but also promotes the expression of both early differentiation markers K1 and K10 and late differentiation marker filaggrin in response to the Ca2+ signal, and seems to sustain the proliferative activity in suprabasal stratified cells. Immunoprecipitation/western blot analysis revealed that fibroblast growth factor 10, similarly to keratinocyte growth factor, is able to induce tyrosine phosphorylation of keratinocyte growth factor receptor and of cellular substrates such as PLCγ. [ABSTRACT FROM AUTHOR]

The human homologue of fz1 (Hfz1) was cloned from a cDNA library. Hfz1 was shown to couple to Wnt signal transduction pathways by its ability to enhance Wnt induced TCF dependent transcription in both autocrine and paracrine modes. Enhanced TCF dependent signaling was dose dependent with respect to both Wnt-3A and Hfz1. Moreover, Hfz1 deletion mutants with truncated carboxy termini showed markedly reduced capacity to enhance Wnt signal transduction. Specificity was demonstrated with respect to signal transduction by different Wnts. While Wnt-3a, -3, -1 and to a lesser extent Wnt-2 cooperated with Hfz1 in the paracrine assay for TCF dependent signaling, neither Wnt-4, -5a, -5b, -6, -7a nor -7b did so, despite similar levels of expression. However, coimmunoprecipitation of Hfz1 with both Wnt-3a and Wnt-5a indicated that TCF dependent signaling in response to Wnts is not determined solely by their ability to bind the receptor. All of these findings provide strong evidence that Hfz1 is a functional partner for certain Wnts in inducing TCF dependent transcription. [ABSTRACT FROM AUTHOR]

Apicomplexan parasite Toxoplasma gondii has three distinct clonal lineages: high, medium and low virulent strains, type I, II and III, respectively. T. gondii avoids the immune response by transforming from fast multiplying tachyzoite to slow multiplying bradyzoite, and establishing a chronic infection. In the present study, we isolated a new strain of T. gondii from cat feces in the Tokachi subprefecture, Hokkaido, Japan and named it as TgCatJpObi1 (Obi1) strain. Genotyping analysis of 12 loci revealed atypical characters close to type II, genotype 4 according to ToxoDB classification. Phenotypically, Obi1 strain shows slow growth rate and the ability of spontaneous cyst formation in both human foreskin fibroblast (HFFs) and mouse peritoneal macrophages in vitro without bradyzoite induction. Parasite virulence was assessed by means of mouse survival upon infection with either Obi1 or ME49 strains. Obi1 strain displayed no mortalities in comparison to type II clonal lineage, ME49 at LD 50 to LD 100 range (1 × 103–106 tachyzoites). Although virulence of Obi1 strain is significantly lower than that of ME49, nucleotide sequences analyses revealed that genes of virulence factors such as Gra15, Rop5, 16, 17, and 18 in Obi1 strain were 100% identical to those in the type II strain. Thus, characterization of a newly isolated strain, Obi1, is crucial to clarify the development of toxoplasmosis in both humans and animals. Unlabelled Image • Toxoplasma gondii (T. gondii) has three virulent lineages named type I, II, and III. • T. gondii tachyzoites avoids the immune system by switching to bradyzoite form. • A spontaneous cyst-forming strain was isolated from Tokachi sub-prefecture, Japan. • Isolated parasite, Obi1 strain is atypical and close to type II, genotype 4 of T. gondii. • Obi1 has a low virulent phenotype when compared to ME49 strain of T. gondii. [ABSTRACT FROM AUTHOR]