Publications by authors named "Hiroyuki Iwata"

58 Publications

Thapsigargin suppresses alpha 1-acid glycoprotein secretion independently of N-glycosylation and ER stress.

Biochem Biophys Res Commun 2021 May 16;552:30-36. Epub 2021 Mar 16.

Laboratory of Veterinary Hygiene, Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1 Yoshida, Yamaguchi, 753-8515, Japan. Electronic address:

Alpha-1 acid glycoprotein (AGP) is a major acute-phase protein that is involved in drug/ligand binding and regulation of immune response. In response to inflammation, AGP secretion from the liver increases, resulting in elevated concentration of plasma AGP. AGP exhibits multiple N-glycosylation sites, and thus, is highly glycosylated. Although AGP glycosylation is considered to affect its functions, the significance of AGP glycosylation for its secretion is unclear. In this study, we investigated the effects of AGP glycosylation using glycosylation-deficient mouse AGP mutants lacking one, four, or all five N-glycosylation sites. Furthermore, we examined the effects of endoplasmic reticulum (ER) stress-inducing reagents, including tunicamycin and thapsigargin, which induce ER stress in an N-glycosylation-dependent and -independent manner, respectively. Here, we found that glycosylation deficiency and ER stress induce a little or no effect on AGP secretion. Conversely, thapsigargin significantly suppressed AGP secretion in glycosylation-independent manner. These findings indicate that AGP secretion is regulated via thapsigargin-sensitive pathway that might be further controlled by the intracellular calcium concentrations.
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http://dx.doi.org/10.1016/j.bbrc.2021.03.017DOI Listing
May 2021

α-Sens: The improved ARE-Nrf2-based sensitization screening assay using normalized transcriptional activity.

Toxicology 2020 06 23;439:152476. Epub 2020 Apr 23.

The United Graduate School of Veterinary Science, Yamaguchi University, Japan.

Two non-animal test methods, KeratinoSens™ and LuSens, have been approved by the Organization of Economic Cooperation and Development (OECD) test guidelines for evaluating the sensitization potential of chemicals, and been positioned as a method for appraising key event (KE)-2, namely, the keratinocyte response component of the Adverse Outcome Pathway (AOP) in sensitization process. However, these two methods require separate cytotoxicity tests to determine the concentrations to be tested in the main test. Therefore, we developed a simple and highly accurate KE-2 test method named α-Sens that uses the dual luciferase assay system and attempted a further application of luciferase-based determination of cell viability to calculate the normalized Antioxidant response element (ARE)-mediated transcriptional activity, named normalized ARE Activity (nAA), to evaluate the sensitizing potential of chemicals. A cell line carrying the ARE-inducible Firefly luciferase reporter gene and Thymidine kinase (TK) promoter-driven Renilla luciferase gene was established and used for the α-Sens. A total of 28 chemicals, consisting of 19 skin sensitizers and nine non-skin sensitizers were tested by this assay system. The α-Sens yielded an accuracy (%), sensitivity (%), and specificity (%) against corresponding values for local lymph node assay of 96.4 %, 95.0 %, and 100 %, respectively, and for human data of 100 % for all. The α-Sens gave clear positive results for phenyl benzoate and eugenol, chemicals for which KeratinoSens™ or LuSens yielded false-negative results, using a new parameter. Our results suggest that better prediction capacity could be achieved by using nAA as a classifier compared to other existing KE-2 test methods. In conclusion, the α-Sens is promising as a simple and highly accurate in vitro skin sensitization test method for evaluation of KE-2.
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http://dx.doi.org/10.1016/j.tox.2020.152476DOI Listing
June 2020

Enzalutamide versus flutamide for castration-resistant prostate cancer after combined androgen blockade therapy with bicalutamide: the OCUU-CRPC study.

Int J Clin Oncol 2020 Mar 28;25(3):486-494. Epub 2019 Sep 28.

Department of Urology, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka, 545-8585, Japan.

Background: Before the androgen target therapy era, flutamide was widely used for castration-resistant prostate cancer in Japan. Enzalutamide is currently the recommended treatment; however, the efficacy and safety of enzalutamide and flutamide after combined androgen blockade therapy with bicalutamide, has not been compared.

Methods: Patients with castration-resistant prostate cancer who received combined androgen blockade therapy with bicalutamide were randomly assigned to receive either enzalutamide or flutamide. The primary endpoint for efficacy was the 3-month prostate-specific antigen response rate. This trial is registered with ClinicalTrials.gov (NCT02346578) and the University hospital Medical Information Network (UMIN000016301).

Results: Overall, 103 patients were enrolled. The 3- (80.8% vs. 35.3%; p < 0.001) and 6-month (73.1% vs. 31.4%; p < 0.001) prostate-specific antigen response rates were higher in the enzalutamide than in the flutamide group. The 3-month disease progression rates (radiographic or prostate-specific antigen progression) were 6.4% and 38.8% in the enzalutamide and flutamide groups, respectively [hazard ratio (HR): 0.16; 95% confidence interval (CI): 0.05-0.47; p < 0.001]; the 6-month rates were 11.4% and 51.1%, respectively (HR 0.22; 95% CI 0.09-0.50; p < 0.001). Enzalutamide provided superior prostate-specific antigen progression-free survival compared with flutamide (HR 0.29; 95% CI 0.15-0.54; p < 0.001). Median time to prostate-specific antigen progression-free survival was not reached and was 6.6 months in the enzalutamide and flutamide groups, respectively.

Conclusions: As an alternative anti-androgen therapy in patients with castration-resistant prostate cancer who fail bicalutamide-combined androgen blockade therapy, enzalutamide provides superior clinical outcomes compared with flutamide. Enzalutamide should be preferred over flutamide in these patients.
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http://dx.doi.org/10.1007/s10147-019-01554-3DOI Listing
March 2020

Effects of Soluble Tumor Necrosis Factor (TNF) on Antibody-Dependent Cellular Cytotoxicity of Therapeutic anti-TNF-α Antibody.

Immunol Invest 2019 Jul 20;48(5):441-450. Epub 2018 Dec 20.

a Chemicals Assessment and Research Center , Chemicals Evaluation and Research Institute , Saitama , Japan.

Anti-TNF antibodies are major therapeutics for rheumatoid arthritis and have been approved for marketing in many countries. Antibody-dependent cellular cytotoxicity (ADCC) is considered to be a potential mechanism of action of anti-TNF antibodies, since some anti-TNF antibodies have been confirmed to induce cytotoxic effects on TNF-producing cells via ADCC and complement-dependent cytotoxicity (CDC) in experiments. In this study, we established a new stable effector cell line expressing human FcγRIIIa, CD16:KHYG-1, and compared the performance of this cell line with that of peripheral blood mononuclear cells (PBMCs) in ADCC assays against CHO-derived target cells expressing protease-sensitive pro-TNF. Although an inhibitory effect of soluble TNF released from pro-TNF expressing cells on ADCC activity was seen, clear dose-responsive ADCC activities were observed even in the presence or absence of TNF-α converting enzyme (TACE) inhibitor. However, significant differences in the ADCC activities in the presence or absence of TACE inhibitor were only noted when CD16:KHYG-1 cells were used as the effector cells. Our findings indicate that soluble TNF may influence ADCC activity of anti-TNF antibody. Moreover, the fact that the influence was able to be detected only in the case using stable effector cell also suggests that the stable effector cell established this time enable highly accurate ADCC measurement.
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http://dx.doi.org/10.1080/08820139.2018.1549067DOI Listing
July 2019

Apoptosis induced by Ibaraki virus does not affect virus replication and cell death in hamster lung HmLu-1 cells.

J Vet Med Sci 2019 Feb 12;81(2):197-203. Epub 2018 Dec 12.

Laboratory of Veterinary Hygiene, Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-8515, Japan.

Ibaraki virus (IBAV) is an arbovirus that is transmitted by biting midges and causes Ibaraki disease in cattle. IBAV induces apoptosis in several mammalian cell lines, and apoptosis in turn facilitates IBAV replication. In addition, virus-induced apoptosis may contribute to mammalian-specific pathogenicity considering that some arboviruses induce apoptosis in mammalian cells but not in insect cells. In this study, we found that when hamster lung cells (HmLu-1) are used as a virus host, IBAV causes severe cytopathic effects with little induction of apoptosis. Furthermore, pharmacological inhibition of apoptosis did not affect IBAV-induced cytotoxicity. These results indicate the existence of an apoptosis-independent pathway in which IBAV replicates and exerts cytotoxicity in mammalian cells.
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http://dx.doi.org/10.1292/jvms.18-0366DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6395211PMC
February 2019

Amino acid starvation accelerates replication of Ibaraki virus.

Virus Res 2019 01 29;260:94-101. Epub 2018 Nov 29.

Laboratory of Veterinary Hygiene, Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1, Yoshida, Yamaguchi, 753-8515, Japan. Electronic address:

Ibaraki virus (IBAV) is a strain of epizootic hemorrhagic disease virus 2 that belongs to the genus Orbivirus of the family Reoviridae. IBAV replication is suppressed by the inhibition of autophagy, and since mechanistic target of rapamycin complex 1 (mTORC1) is a key regulator of autophagy, we examined if mTORC1 inhibition by amino acid starvation or mTOR inhibitors (Torin 1 and rapamycin) affects IBAV replication. We found that IBAV replication is significantly enhanced after amino acid starvation of host cells, but not after treatment with mTOR inhibitors, during early stages of viral infection (0-1 hpi). Notably, inhibition of mTORC1 by amino acid starvation was reversible and thus restricted to 0-1 hpi, whereas mTOR inhibitors sustainably suppressed mTORC1 even after the 1-h treatment, suggesting that mTORC1 suppression itself does not affect IBAV replication. To investigate the mechanism of enhanced IBAV replication by amino acid starvation, we examined the endocytic pathway, since IBAV utilizes acidification of endosomes as a trigger for viral replication. Accordingly, we found that amino acid starvation, but not mTOR inhibitors, strongly induced acidification of endosomes/lysosomes and that inhibition of endosomal acidification by bafilomycin A1 effectively blocked enhancement of IBAV replication. Altogether, the inactivation of mTORC1 by amino acid starvation during early stages of infection enhances acidification of endosomes, which in turn enhances IBAV replication.
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http://dx.doi.org/10.1016/j.virusres.2018.10.008DOI Listing
January 2019

Suprapubic catheterization is expedient for the surgical excision of female genital tumors.

Dermatol Ther 2018 11 28;31(6):e12732. Epub 2018 Oct 28.

Department of Urology, Itami City Hospital, Itami, Japan.

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http://dx.doi.org/10.1111/dth.12732DOI Listing
November 2018

Electrochemical polymerization of pyrene and aniline exclusively inside the pores of activated carbon for high-performance asymmetric electrochemical capacitors.

Nanoscale 2018 May;10(20):9760-9772

Department of Applied Chemistry, Aichi Institute of Technology, Yachigusa 1247, Yakusa-cho, Toyota, 470-0392, Japan.

An asymmetric polymer capacitor was prepared from pyrene (PY), aniline (ANI), and commercially available activated carbon (AC) through a solvent-free preparation. PY and ANI were adsorbed into the AC host material in the gas phase and electrochemically polymerized exclusively inside the AC pores in an aqueous H2SO4 electrolyte (1 M). No volumetric expansion of the AC particles occurred upon the adsorption of monomers and their subsequent polymerizations; thus, the volumetric capacitance was enhanced by the inclusion of pseudocapacitive polypyrene (PPY) and polyaniline (PANI). The PPY and PANI structures formed inside the AC pores are very thin and have a large contact area with the conductive carbon surfaces. Therefore, the charge transfer distance between the polymers and the carbon surfaces was drastically shortened, significantly reducing the charge transfer resistance; i.e., high power density. The maximum volumetric capacitances for the PPY- and PANI-hybridized AC reached 314 and 299 F cm-3, respectively. Moreover, the strong adhesion derived from their large contact areas and adsorption capability of AC endow these materials with long cycle lifetimes. The PPY- and PANI-hybridized AC have different redox potentials and can be assembled into an asymmetric capacitor. The volumetric capacitance obtained for the asymmetric capacitor further surpassed that of the symmetric capacitor consisting of pristine AC, with high power density and long cycle lifetimes.
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http://dx.doi.org/10.1039/c8nr01529eDOI Listing
May 2018

Thermal stability of laser-induced modified volumes in Si as studied by in situ and ex situ heating experiments.

Microscopy (Oxf) 2018 Apr;67(2):112-120

Research & Development Department, Hamamatsu Photonics KK, 314-5 Shimokanzo, Iwata, Shizuoka 438-0193, Japan.

Radiation of a permeable laser beam into Si induces considerable modification of structures. Thermal stability of the laser-induced modified volumes (LIMV's) was studied comprehensively by means of in situ and ex situ heating experiments using transmission electron microscopy. The behavior in the tail region of a LIMV can be understood by dislocation theory, while that of a void formed at the very focus of a laser beam cannot be understood easily.
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http://dx.doi.org/10.1093/jmicro/dfy008DOI Listing
April 2018

Crystal structures of high-pressure phases formed in Si by laser irradiation.

Microscopy (Oxf) 2018 Feb;67(1):30-36

Research Institute for Industrial Technology, Aichi Institute of Technology, Yachikusa1247, Yakusa-cho, Toyota, Aichi 470-0392, Japan.

Internal modification induced in Si by a permeable pulse laser was investigated by transmission electron microscopy. A laser induced modified volume (LIMV) was a cylindrical rod along the track of a laser beam with the head at the focus of the laser beam. In the LIMV, beside voids, dislocations, micro-cracks and what had been supposed to be an unidentified high-pressure phase (hpp) of Si were observed in LIMV. The so-called 'hpp' was identified mostly as diamond Si.
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http://dx.doi.org/10.1093/jmicro/dfx128DOI Listing
February 2018

A multichannel-near-infrared-spectroscopy-triggered robotic hand rehabilitation system for stroke patients.

IEEE Int Conf Rehabil Robot 2017 07;2017:158-163

There is a demand for a new neurorehabilitation modality with a brain-computer interface for stroke patients with insufficient or no remaining hand motor function. We previously developed a robotic hand rehabilitation system triggered by multichannel near-infrared spectroscopy (NIRS) to address this demand. In a preliminary prototype system, a robotic hand orthosis, providing one degree-of-freedom motion for a hand's closing and opening, is triggered by a wireless command from a NIRS system, capturing a subject's motor cortex activation. To examine the feasibility of the prototype, we conducted a preliminary test involving six neurologically intact participants. The test comprised a series of evaluations for two aspects of neurorehabilitation training in a real-time manner: classification accuracy and execution time. The effects of classification-related factors, namely the algorithm, signal type, and number of NIRS channels, were investigated. In the comparison of algorithms, linear discrimination analysis performed better than the support vector machine in terms of both accuracy and training time. The oxyhemoglobin versus deoxyhemoglobin comparison revealed that the two concentrations almost equally contribute to the hand motion estimation. The relationship between the number of NIRS channels and accuracy indicated that a certain number of channels are needed and suggested a need for a method of selecting informative channels. The computation time of 5.84 ms was acceptable for our purpose. Overall, the preliminary prototype showed sufficient feasibility for further development and clinical testing with stroke patients.
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http://dx.doi.org/10.1109/ICORR.2017.8009239DOI Listing
July 2017

Dynamin-dependent amino acid endocytosis activates mechanistic target of rapamycin complex 1 (mTORC1).

J Biol Chem 2017 11 14;292(44):18052-18061. Epub 2017 Aug 14.

From the Laboratory of Veterinary Hygiene, Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-8515, Japan

The mechanistic target of rapamycin complex 1 (mTORC1) is a master regulator of protein synthesis and potential target for modifying cellular metabolism in various conditions, including cancer and aging. mTORC1 activity is tightly regulated by the availability of extracellular amino acids, and previous studies have revealed that amino acids in the extracellular fluid are transported to the lysosomal lumen. There, amino acids induce recruitment of cytoplasmic mTORC1 to the lysosome by the Rag GTPases, followed by mTORC1 activation by the small GTPase Ras homolog enriched in brain (Rheb). However, how the extracellular amino acids reach the lysosomal lumen and activate mTORC1 remains unclear. Here, we show that amino acid uptake by dynamin-dependent endocytosis plays a critical role in mTORC1 activation. We found that mTORC1 is inactivated when endocytosis is inhibited by overexpression of a dominant-negative form of dynamin 2 or by pharmacological inhibition of dynamin or clathrin. Consistently, the recruitment of mTORC1 to the lysosome was suppressed by the dynamin inhibition. The activity and lysosomal recruitment of mTORC1 were rescued by increasing intracellular amino acids via cycloheximide exposure or by Rag overexpression, indicating that amino acid deprivation is the main cause of mTORC1 inactivation via the dynamin inhibition. We further show that endocytosis inhibition does not induce autophagy even though mTORC1 inactivation is known to strongly induce autophagy. These findings open new perspectives for the use of endocytosis inhibitors as potential agents that can effectively inhibit nutrient utilization and shut down the upstream signals that activate mTORC1.
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http://dx.doi.org/10.1074/jbc.M117.776443DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5672031PMC
November 2017

Electron microscopy of voids in Si formed by permeable pulse laser irradiation.

Microscopy (Oxf) 2017 Oct;66(5):328-336

Research Institute for Industrial Technology, Aichi Institute of Technology, 1247 Yachigusa, Yakusa, Toyota 470-0392, Japan.

Voids formed in Si by permeable laser irradiation were investigated by comprehensive electron microscopy. Two types of voids were identified: Type (1): This type was formed mostly closer to the entrance surface of a laser, and a considerable volume of a non-diamond Si (DS) phase was formed in the surrounding matrix. Type (2): This type was formed at the focus of an incident laser, and none of dislocations, cracks and non-DS phase was observed in the surrounding matrix. Type (1) voids are considered to be formed to accommodate volume change resulting from transformation from DS to the non-DS. However, it is difficult to explain formation of Type (2) voids by this mechanism.
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http://dx.doi.org/10.1093/jmicro/dfx024DOI Listing
October 2017

Linear IgA Bullous Dermatosis Associated with Immunoglobulin Light-chain Amyloidosis.

Acta Derm Venereol 2017 04;97(4):528-529

Department of Dermatology, Hokkaido University Graduate School of Medicine, , Japan.

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http://dx.doi.org/10.2340/00015555-2590DOI Listing
April 2017

The requirement of environmental acidification for Ibaraki virus infection to host cells.

J Vet Med Sci 2016 Jan 28;78(1):153-6. Epub 2015 Aug 28.

Laboratory of Veterinary Hygiene, Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-0841, Japan.

The effect of environmental acidification on Ibaraki virus (IBAV) infection was tested using endosomal inhibitory chemicals and low pH treatment. Treatment of target cells with endosomal inhibitors significantly decreased the progeny virus production. IBAV outer capsid proteins, VP5 and VP2, were removed from virion when purified IBAV was exposed to low pH environment. Further experiment showed that the exposure to low pH buffer facilitated IBAV infection when the cellular endosomal pathway was impaired by bafilomycin A1. Results obtained in this study suggest that acidic environment is essential to initiate IBAV infection.
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http://dx.doi.org/10.1292/jvms.15-0222DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4751137PMC
January 2016

The effect of glycosylation on cytotoxicity of Ibaraki virus nonstructural protein NS3.

J Vet Med Sci 2016 Jan 16;77(12):1611-6. Epub 2015 Jul 16.

Laboratory of Veterinary Hygiene, Joint Faculty of Veterinary Medicine, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-0841, Japan.

The cytotoxicity of Ibaraki virus nonstructural protein NS3 was confirmed, and the contribution of glycosylation to this activity was examined by using glycosylation mutants of NS3 generated by site-directed mutagenesis. The expression of NS3 resulted in leakage of lactate dehydrogenase to the culture supernatant, suggesting the cytotoxicity of this protein. The lack of glycosylation impaired the transport of NS3 to the plasma membrane and resulted in reduced cytotoxicity. Combined with the previous observation that NS3 glycosylation was specifically observed in mammalian cells (Urata et al., Virus Research 2014), it was suggested that the alteration of NS3 cytotoxicity through modulating glycosylation is one of the strategies to achieve host specific pathogenisity of Ibaraki virus between mammals and vector arthropods.
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http://dx.doi.org/10.1292/jvms.15-0121DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4710717PMC
January 2016

Ayadualin, a novel RGD peptide with dual antihemostatic activities from the sand fly Lutzomyia ayacuchensis, a vector of Andean-type cutaneous leishmaniasis.

Biochimie 2015 May 24;112:49-56. Epub 2015 Feb 24.

Department of Parasitology, Kochi Medical School, Kochi University, Kochi, Japan; Centro de Biomedicina, Universidad Central del Ecuador, Quito, Ecuador; Prometeo, Secretaría Nacional de Educacion Superior, Ciencia, Tecnologia e Innovacion (SENESCYT), Ecuador.

Sequence analysis of the Lutzomyia (Lu.) ayacuchensis salivary gland cDNA library identified a short peptide containing an RGD (Arg-Gly-Asp) sequence flanked by two cysteine residues in the C-terminal end as the most abundant transcript. In the present study, a recombinant protein of the RGD-containing peptide, designated ayadualin, was expressed in Escherichia coli and its activity was characterized. Ayadualin inhibited both collagen and ADP-induced platelet aggregations by interfering with the binding of integrin αIIbβ3 to fibrinogen. The RGD sequence and cysteine residues located on both sides of the RGD sequence were essential for the inhibitory action. Moreover, ayadualin efficiently inhibited the intrinsic blood coagulation pathway irrespective of the RGD sequence. Measuring the enzymatic activity of coagulation factors using chromogenic substrates revealed that ayadualin efficiently inhibited factor XIIa (FXIIa) activity in a dose-dependent manner. In addition, pre-incubation of ayadualin with FXII inhibited FXIIa activity, while activated FXIIa was not affected by ayadualin, indicating that ayadualin inhibits the activation of FXII, but not enzymatic activity of FXIIa. These results indicated that ayadualin plays an important role in the blood feeding of Lu. ayacuchensis by inhibiting host hemostasis via dual mechanisms.
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http://dx.doi.org/10.1016/j.biochi.2015.02.011DOI Listing
May 2015

The host specific NS3 glycosylation pattern reflects the virulence of Ibaraki virus in different hosts.

Virus Res 2014 Mar 31;181:6-10. Epub 2013 Dec 31.

Laboratory of Veterinary Hygiene, Joint Faculty of Veterinary Medicine, Yamaguchi University, Japan.

The non-structural protein NS3 was investigated in Ibaraki virus (IBAV), an epizootic hemorrhagic disease virus, serotype 2. Degree of NS3 glycosylation, cytopathic effect, and virus release efficiency were compared between mammalian and insect cells. The molecular weight of synthesized NS3 was compared in Western blot analysis following the removal of the glycochain by PNGase F treatment and revealed that glycosylation of NS3 occurred only in mammalian cells. Also, it was revealed that the amount of infectious IBAV in the extracellular fraction continued to increase for insect cells even after 60h post infection without disrupting cells. These results suggested that glycosylation of NS3 controls pathogenicity of IBAV in host cells to protect vector insects by altering the release pathway of assembled progeny viruses.
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http://dx.doi.org/10.1016/j.virusres.2013.12.027DOI Listing
March 2014

Primary lung cancer complicated by malignant lymphoma in two cases of epstein-barr virus infection.

Case Rep Oncol 2012 May 10;5(2):367-72. Epub 2012 Jul 10.

Department of Internal Medicine and, Chuno Kosei Hospital, Seki, Japan.

Background: Double cancer is defined as the co-existence of two pathologically distinct cancers. Double cancer consisting of a lung adenocarcinoma and a malignant lymphoma has seldom been reported in time synchronous cases or prior to cases of primary lung cancer, except in those after treatment for malignant lymphoma.

Case Presentation: Case 1 was a 71-year-old woman who was treated at our hospital for chronic hepatitis C, nontuberculous mycobacteria infection, and bronchiectasis. She was diagnosed with a stage IV lung adenocarcinoma (cT1bN2M1b) with a synchronous complicating diffuse large B-cell-type lymphoma. Case 2 was a 62-year-old man who had undergone resection of a stage IB lung adenocarcinoma (pT2aN0M0). Thirty months after the surgery, a diffuse large B-cell-type lymphoma was discovered. In both cases, high antiviral capsid antigen IgG antibody titers were observed.

Conclusion: Epstein-Barr virus may be associated with the incidence of multiple cancers given the pathological evidence from our two double cancer cases.
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http://dx.doi.org/10.1159/000341158DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3409503PMC
May 2012

Prevalence and epidemiological relationship of CMY-2 AmpC β-lactamase and CTX-M extended-spectrum β-lactamase-producing Escherichia coli isolates from broiler farms in Japan.

J Vet Med Sci 2013 15;75(8):1009-15. Epub 2013 Mar 15.

Yamaguchi Prefectural Institute of Public Health and Environment, 2-5-67 Aoi, Yamaguchi 753-0821, Japan.

To evaluate the prevalence of extended-spectrum cephalosporin (ESC)-resistant Enterobacteriaceae in broiler chickens, 41 rectal samples taken from 4 commercial farms were examined. Desoxycholate hydrogen sulfide lactose agars, supplemented with either 4 μg/ml cefotaxime or 16 μg/ml ceftazidime, were used to screen ESC-resistant bacteria. ESC-resistant bacteria were isolated from all samples. Of the 164 ESC-resistant bacteria (included 4 isolates per a sample), 163 were Escherichia coli, while 1 isolate was identified as Enterobacter cloacae. Extended-spectrum β-lactamase (ESBL) genes and plasmid-mediated AmpC β-lactamase genes in the isolates were determined by PCR and sequencing. One AmpC β-lactamase gene, bla(CMY-2) (66%), and 4 ESBL genes, bla(CTX-M-1) (26%), bla(CTX-M-55) (10%), bla(SHV-5) (4%) and bla(CTX-M-2) (3%), were detected in the E. coli isolates. The epidemiological relationship of the CMY-2 and CTX-M β-lactamase-producing isolates among the farms was analyzed by pulsed-field gel electrophoresis using the XbaI restriction enzyme. Forty-one (Y1-Y41) and 14 (X1-X14) clusters were found in the CMY-2 and CTX-M-carrying E. coli isolates, respectively. Some clusters included isolates derived from more than 1 farm, indicating some cross-contamination of clonal strains and spread of CMY-2 AmpC β-lactamase or CTX-M ESBL among the farms.
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http://dx.doi.org/10.1292/jvms.12-0453DOI Listing
April 2014

Genetic diversity of the mitochondrial cytochrome b gene in Lutzomyia spp., with special reference to Lutzomyia peruensis, a main vector of Leishmania (Viannia) peruviana in the Peruvian Andes.

Acta Trop 2013 May 12;126(2):156-63. Epub 2013 Feb 12.

Laboratory of Veterinary Hygiene, Faculty of Agriculture, Yamaguchi University, Yamaguchi, Japan.

The genetic divergence caused by genetic drift and/or selection is suggested to affect the vectorial capacity and insecticide susceptibility of sand flies, as well as other arthropods. In the present study, cytochrome b (cyt b) gene sequences were determined in 13 species circulating in Peru to establish a basis for analysis of the genetic structure, and the intraspecific genetic diversity was assessed in the Lutzomyia (Lu.) peruensis, a main vector species of Leishmania (Viannia) peruviana in Peruvian Andes. Analysis of intraspecific genetic diversity in the cyt b gene sequences from 36 Lu. peruensis identified 3 highly polymorphic sites in the middle region of the gene. Haplotype and gene network analyses were performed on the cyt b gene sequences of 130 Lu. peruensis in 9 Andean areas from 3 Departments (Ancash, Lima and La Libertad). The results showed that the populations of La Libertad were highly polymorphic and that their haplotypes were distinct from those of Ancash and Lima, where dominant haplotypes were observed, suggesting that a population bottleneck may have occurred in Ancash and Lima, but not in La Libertad. The present study indicated that the middle region of the cyt b gene is useful for the analysis of genetic structure in sand fly populations.
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http://dx.doi.org/10.1016/j.actatropica.2013.02.007DOI Listing
May 2013

Dimiconin, a novel coagulation inhibitor from the kissing bug, Triatoma dimidiata, a vector of Chagas disease.

J Exp Biol 2012 Oct 5;215(Pt 20):3597-602. Epub 2012 Jul 5.

Laboratory of Veterinary Hygiene, Yamaguchi University, Yamaguchi, 753-8515, Japan.

Sequence analysis of a Triatoma dimidiata salivary gland cDNA library resulted in the identification of two transcripts (Td60 and Td101) homologous to triabin, an inhibitor of thrombin in Triatoma pallidipennis saliva. In the present study, a recombinant protein of Td60, designated dimiconin, was expressed in Escherichia coli and its activity was characterized. The resulting protein inhibited the intrinsic but not extrinsic blood coagulation pathway, suggesting that dimiconin is not a thrombin inhibitor. Measurement of the enzymatic activity of coagulation factors using chromogenic substrates revealed that dimiconin efficiently inhibited factor XIIa (FXIIa) activity in a dose-dependent manner. In addition, pre-incubation of dimiconin with FXII effectively inhibited FXIIa activity whereas dimiconin did not affect already activated FXIIa, indicating that dimiconin inhibits the activation of FXII but not the enzymatic activity of FXIIa. These results show that dimiconin is an inhibitor of the contact phase initiated by FXII activation in the blood coagulation cascade, which differs from the bioactivity of triabin.
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http://dx.doi.org/10.1242/jeb.074211DOI Listing
October 2012

Feline infectious peritonitis virus with a large deletion in the 5'-terminal region of the spike gene retains its virulence for cats.

J Gen Virol 2012 Sep 20;93(Pt 9):1930-1934. Epub 2012 Jun 20.

Laboratories of Veterinary Microbiology, Faculty of Agriculture, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-8515, Japan.

In this study, the Japanese strain of type I feline infectious peritonitis virus (FIPV), C3663, was found to have a large deletion of 735 bp within the gene encoding the spike (S) protein, with a deduced loss of 245 aa of the N-terminal region of the S protein. This deletion is similar to that observed in porcine respiratory coronavirus (PRCoV) when compared to transmissible gastroenteritis virus, which correlates with reduced virulence. By analogy to PRCoV, we expected that the pathogenicity of C3663 may be attenuated in cats. However, two of four cats inoculated with C3663 died of FIP, and a third C3663-inoculated cat showed FIP lesions at 91 days after challenge. These results indicate that the 5'-terminal region of the S gene is not essential for the development of FIP.
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http://dx.doi.org/10.1099/vir.0.043992-0DOI Listing
September 2012

The E89K Mutation in the Matrix Protein of the Measles Virus Affects In Vitro Cell Death and Virus Replication Efficiency in Human PBMC.

Open Virol J 2012 8;6:68-72. Epub 2012 Jun 8.

Department of Veterinary Microbiology, University of Miyazaki, Miyazaki 889-2192, Japan.

Matrix protein is known to have an important role in the process of virus assembly and virion release during measles virus replication. In the present in vitro study, a single mutation of E89K in the matrix protein was shown to affect cell death and virus replication efficiency in human PBMC. One strain with this mutation caused less cell death than the parental virus, and possessed high virus replication efficiency. Moreover, by Annexin V-FITC staining, polycaspase FLICA staining, and double labeling with poly-caspase FLICA and the Hoechst stain, the cell death seen was shown to be apoptosis.
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http://dx.doi.org/10.2174/1874357901206010068DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3377886PMC
August 2012

Emergence of Salmonella enterica serovar infantis harboring IncI1 plasmid with bla(CTX-M-14) in a broiler farm in Japan.

J Vet Med Sci 2012 Sep 16;74(9):1213-6. Epub 2012 May 16.

Yamaguchi Prefectural Institute of Public Health and Environment, 2-5-67 Aoi, Yamaguchi 753-0821, Japan.

Cefotaxime (CTX)-resistant and -susceptible Salmonella enterica serovar Infantis isolates obtained from broilers raised on a farm in January 2010 in Japan were characterized to establish their resistance determinants. The CTX-resistant isolates produced CTX-M-14 extended-spectrum β-lactamase and harbored 2 distinct plasmid of approximately 140- and 95-kb, whereas the CTX-susceptible isolates harbored one 140-kb plasmid. The 95-kb plasmids were replicon typed as IncI1 carrying the bla(CTX-M-14) gene, while the 140-kb plasmids were IncP and harbored the aphA1, aadA1, tetA, and sul1 genes. Genetic fingerprinting by pulsed-field gel electrophoresis revealed similar macrorestriction profiles amongst CTX-resistant and susceptible isolates, suggesting a clonal relationship. The presence of CTX-resistant S. Infantis on a broiler farm has occurred through the acquisition of IncI1 resistance plasmid.
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http://dx.doi.org/10.1292/jvms.11-0488DOI Listing
September 2012

Genotyping of sand fly species in Peruvian Andes where leishmaniasis is endemic.

Acta Trop 2012 Feb 12;121(2):93-8. Epub 2011 Oct 12.

Laboratory of Veterinary Hygiene, Faculty of Agriculture, Yamaguchi University, Japan.

Genotyping of sand fly species circulating in Peru was established on the basis of PCR-restriction fragment length polymorphisms (RFLPs) of the 18S ribosomal RNA (rRNA) gene. The sequences of 18S rRNA gene fragments from 12 Lutzomyia and 1 Warileya species were determined and their RFLP-patterns were analyzed. Consequently, RFLP analysis with the restriction enzyme AfaI and then HapII or KpnI, followed by XspI successfully differentiated them. Intraspecific genetic diversity affecting RFLP-patterns was not detected in the specimens collected from 24 areas of 8 departments. The genotyping was applied to the surveillance of sand flies collected from Andean areas where leishmaniasis is endemic, and its usability was verified. The present method promises to be a powerful tool for the classification and surveillance of sand flies circulating in Peru.
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http://dx.doi.org/10.1016/j.actatropica.2011.10.004DOI Listing
February 2012

Effect of cooled and chlorinated chiller water on Campylobacter and coliform counts on broiler carcasses during chilling at a middle-size poultry processing plant.

J Vet Med Sci 2012 Jan 6;74(1):129-33. Epub 2011 Sep 6.

Iwakuni Health Welfare and Center of Yamaguchi Prefecture, Japan.

To evaluate the effect of cooled and chlorinated chill water for Campylobacter and coliforms at a middle-size processing plant which was considered to be difficult for eliminate pathogenic bacteria on carcasses, following three conditions were examined; keeping temperature at < 20, < 10 and < 10°C, and chlorine concentration at < 50, < 50 and 50 to 70 ppm during processing in experiment 1, 2 and 3 respectively. Fifteen prechill and 15 postchill carcasses were examined in each experiment. In lower temperature of experiment 2, decreasing rate (%) of coliforms was significantly higher (P<0.01) than that in experiment 1. In higher chlorination of experiment 3, no Campylobacter was detected from all postchill carcasses.
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http://dx.doi.org/10.1292/jvms.11-0167DOI Listing
January 2012

Characterization of monoclonal antibodies against canine P-selectin glycoprotein ligand-1 (PSGL-1).

Vet Immunol Immunopathol 2011 Jul 21;142(1-2):119-25. Epub 2011 Apr 21.

Laboratory of Veterinary Internal Medicine, Department of Veterinary Medicine, Faculty of Agriculture, Yamaguchi University, 1677-1 Yoshida, Yamaguchi 753-8515, Japan.

Thirteen different monoclonal antibodies against canine P-selectin glycoprotein ligand-1 (cPSGL-1) were obtained by immunization of rats with cells of a canine lymphoma cell line (Ema). O-sialoglycoprotein endopeptidase treatment of Ema cells showed that all of these antibodies recognized O-glycosylated peptides of canine PSGL-1. Experiments using deletion or point mutants of cPSGL-1 indicated that these antibodies could be categorized into several groups based on their cPSGL-1 recognition characteristics. These anti-cPSGL-1 monoclonal antibodies will be useful for analysis of the canine P-selectin and PSGL-1 system.
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http://dx.doi.org/10.1016/j.vetimm.2011.04.009DOI Listing
July 2011

Natural infections of man-biting sand flies by Leishmania and Trypanosoma species in the northern Peruvian Andes.

Vector Borne Zoonotic Dis 2011 May 18;11(5):515-21. Epub 2010 Oct 18.

Laboratory of Veterinary Hygiene, Faculty of Agriculture, Yamaguchi University, Yamaguchi, Japan.

The natural infection of sand flies by Leishmania species was studied in the Andean areas of Peru where cutaneous leishmaniasis caused by Leishmania (Viannia) peruviana is endemic. Sand flies were captured by human bait and Center for Disease Control (CDC) light trap catches at Nambuque and Padregual, Department of La Libertad, Peru, and morphologically identified. Among 377 female sand flies dissected, the two dominant man-biting species were Lutzomyia (Helcocyrtomyia) peruensis (211 flies) and Lutzomyia (Helcocyrtomyia) caballeroi (151 flies). Another sand fly species captured by light trap was Warileya phlebotomanica (15 flies). The natural infection of sand flies by flagellates was detected in 1.4% of Lu. (H.) peruensis and 2.6% of Lu. (H.) caballeroi, and the parasite species were identified as Le. (V.) peruviana and Trypanosoma avium, respectively, by molecular biological methods. The results indicated that the vector species responsible for the transmission of leishmaniasis in the study areas is Lu. (H.) peruensis. In addition, the presence of Trypanosoma in man-biting sand fly species means that more careful consideration is necessary for vector research in areas of Andean Peru where leishmaniasis is endemic.
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http://dx.doi.org/10.1089/vbz.2010.0138DOI Listing
May 2011

Use of FTA cards for direct sampling of patients' lesions in the ecological study of cutaneous leishmaniasis.

J Clin Microbiol 2010 Oct 18;48(10):3661-5. Epub 2010 Aug 18.

Department of Veterinary Hygiene, Faculty of Agriculture, Yamaguchi University, Yamaguchi, Japan.

The FTA card (Whatman) was assessed for its utility as a molecular epidemiological tool in collecting samples from patients with leishmaniasis in Peru because the card has a variety of merits; it is less invasive for patients and easy to handle for both physicians and other medical personnel for sample collection or diagnosis, in addition to its simplicity and easy countrywide and/or intercountry transportation for analysis. Samples were collected from 132 patients suspected of having leishmaniasis, and Leishmania species were successfully identified in samples from 81 patients in 15 departments of Peru by cytochrome b and mannose phosphate isomerase gene analyses. Of these, 61.7% were identified as Leishmania (Viannia) peruviana, 22.2% as L. (V.) braziliensis, 12.3% as L. (V.) guyanensis, 2.5% as L. (V.) shawi, and 1.2% as L. (V.) lainsoni. The three predominant species, L. (V.) peruviana, L. (V.) braziliensis, and L. (V.) guyanensis, were mainly found in the Andean highlands, in the tropical rainforest, and in northern and central rainforest regions, respectively. This is the first time L. (V.) shawi has been identified outside Brazil. The present study showed that the FTA card will be a useful tool for the ecological study of different forms of leishmaniasis. Furthermore, collecting samples directly from patients' lesions by using the FTA card eliminates (i) the possibility of contamination of Leishmania isolates during short- and/or long-term passages of culture in vitro in each laboratory and (ii) pain and suffering of patients from taking samples by skin biopsy.
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http://dx.doi.org/10.1128/JCM.00498-10DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2953078PMC
October 2010