Publications by authors named "Atsuhiko Hasegawa"

Article Synopsis
  • - A small percentage of people infected with HTLV-1 can develop adult T-cell leukemia/lymphoma, a tough-to-treat disease, due to impaired CTLs, which are essential for fighting off the virus and cancer cells.
  • - Researchers used Japanese monkeys infected with STLV-1 (similar to HTLV-1) to test a therapeutic vaccine made from their own blood cells, which activated their CTLs and showed promising results in boosting immune responses.
  • - Vaccinated monkeys displayed increased STLV-1-specific CTL activity and a reduction in viral load after vaccination, but the immune responses peaked at 3-4 months and required additional boosters to maintain effectiveness over time.
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Immunomodulatory imide drugs (IMiDs), such as lenalidomide and pomalidomide, exert pleiotropic effects, e.g., antitumor effects in multiple myeloma, by binding the protein Cereblon and altering its substrate specificity.

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Superheated water extraction (SWE) of pesticide residues in a cabbage sample was demonstrated. The recovery yields of several relatively polar pesticides (log P < 3) by the spike-and-recovery method at 100°C were acceptable. Increasing the extraction temperature up to 150°C led to enhanced extraction efficiency except for pesticides that induced degradation.

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Activation of CD8 Tax-specific CTL is a new therapeutic concept for adult T-cell leukemia (ATL) caused by HTLV-1. A recent clinical study of the dendritic cell vaccine pulsed with Tax peptides corresponding to CTL epitopes showed promising outcomes in ATL patients possessing limited human leukocyte antigen (HLA) alleles. In this study, we aimed to develop another immunotherapy to activate Tax-specific CTL without HLA limitation by using patients' own HTLV-1-infected cells as a vaccine.

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Human T-cell leukemia virus type-1 (HTLV-1) causes adult T-cell leukemia/lymphoma (ATL), HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), and other inflammatory diseases. There is no disease-specific difference in viral strains, and it is unclear how HTLV-1 causes such different diseases manifesting as lymphoproliferation or inflammation. Although some progress has been made in therapies for these diseases, the prognosis for ATL is still dismal and HAM/TSP remains an intractable disease.

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Reverse transcription of retroviral RNA is accomplished through a minus-strand strong stop cDNA (-sscDNA) synthesis and subsequent strand-transfer reactions. We have previously reported a critical role of guanosine (G) number at 5'-terminal of HIV-1 RNA for successful strand-transfer of -sscDNA. In this study, role(s) of the cap consisting of 7-methyl guanosine (G), a hallmark of transcripts generated by RNA polymerase II, at the 5'-end G nucleotide (5'-G) of HIV-1 RNA were examined.

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Adult T-cell leukemia/lymphoma (ATL) is an aggressive lymphoproliferative disease caused by human T-cell leukemia virus type 1 (HTLV-1). Multi-agent chemotherapy can reduce ATL cells but frequently allows relapses within a short period of time. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) following chemotherapy is now a standard therapy for ATL in Japan as it can achieve long-term remission in approximately one-third of recipient ATL patients; however, it also has a risk of treatment-related mortality.

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In the initial online publication, the name of author Hock Siew Han was given incorrectly as Han Hock Siew. The original article has been corrected.

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To clarify the terbinafine (TRF) resistance mechanism in a TRF-resistant strain of Microsporum canis, the expression of the pleiotropic drug resistance (PDR1), multidrug resistance (MDR1), MDR2 and MDR4 genes were investigated by real-time quantitative PCR (RT-qPCR) analysis, given the known interaction of the corresponding proteins with antifungals and with the efflux blocker FK506. The expression of the PDR1, MDR1, MDR2 and MDR4 genes was 2-4 times higher in the TRF-resistant strain grown in the presence of 0.14 µg/mL of TRF than in TRF-susceptible strains cultured in the absence of TRF.

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A Cryptococcus neoformans var. grubii strain, NUBS14020, was the first fluconazole (FLZ)-resistant strain isolated from a feline cryptococcosis. Subsequent work demonstrated that multi-azole-resistant strains are readily isolated from FLZ-resistant strains by culturing in medium containing voriconazole (VRZ).

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Human T-cell leukemia virus type-1 (HTLV-1) causes two distinct diseases, adult T-cell leukemia/lymphoma (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Since there are no disease-specific differences among HTLV-1 strains, the etiological mechanisms separating these respective lymphoproliferative and inflammatory diseases are not well understood. In this study, by using IL-2-dependent HTLV-1-infected T-cell lines (ILTs) established from patients with ATL and HAM/TSP, we demonstrate that the anti-inflammatory cytokine IL-10 and its downstream signals potentially act as a switch for proliferation in HTLV-1-infected cells.

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Infant humans and rhesus macaques infected with the human or simian immunodeficiency virus (HIV or SIV), respectively, express higher viral loads and progress more rapidly to AIDS than infected adults. Activated memory CD4 T cells in intestinal tissues are major primary target cells for SIV/HIV infection, and massive depletion of these cells is considered a major cause of immunodeficiency. Monocytes and macrophages are important cells of innate immunity and also are targets of HIV/SIV infection.

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Human T-cell leukaemia virus type 1 (HTLV-1) is a human retrovirus that is a causative agent of adult T-cell leukaemia/lymphoma (ATL) and is mainly transmitted from an infected mother to her child via breastfeeding. Such an HTLV-1 infection during childhood is believed to be a risk factor for ATL development. Although it has been suggested that an increased proviral load (PVL), a higher titre of antibody (Ab) in the infected mother and prolonged breastfeeding are associated with an increased risk of mother-to-child transmission (MTCT), the mechanisms underlying MTCT of HTLV-1 remain largely unknown.

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Adult T cell leukemia/lymphoma (ATL), a CD4 T cell malignancy with a poor prognosis, is caused by human T cell leukemia virus type 1 (HTLV-1) infection. High proviral load (PVL) is a risk factor for the progression to ATL. We previously reported that some asymptomatic carriers had severely reduced functions of CTLs against HTLV-1 Tax, the major target Ag.

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In this study, we report the first isolation of Aspergillus allahabadii from a Japanese cormorant with pulmonary aspergillosis. We performed molecular identification and antifungal susceptibility testing with the E-test. A 7-month-old male cormorant died because of uric acid deposition secondary to dehydration.

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Unlabelled: Nonenzymatic roles for HIV-1 integrase (IN) at steps prior to the enzymatic integration step have been reported. To obtain structural and functional insights into the nonenzymatic roles of IN, we performed genetic analyses of HIV-1 IN, focusing on a highly conserved Tyr15 in the N-terminal domain (NTD), which has previously been shown to regulate an equilibrium state between two NTD dimer conformations. Replacement of Tyr15 with alanine, histidine, or tryptophan prevented HIV-1 infection and caused severe impairment of reverse transcription without apparent defects in reverse transcriptase (RT) or in capsid disassembly kinetics after entry into cells.

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Prototheca zopfii is an achlorophyllic alga that causes bovine mastitis, resulting in a reduction in milk production and the secretion of thin, watery milk with white flakes. This study evaluated the use of an ELISA system for distinguishing cows with mastitis due to P. zopfii genotype 2 from healthy cows and cows with chronic candidal mastitis.

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Infection by Trichophyton tonsurans is an emerging fungal epidemic in Japan. Itraconazole (ITZ) and terbinafine have been used for the treatment of this infection for 15 years. However, patients with T.

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Azole resistance in Aspergillus fumigatus is mainly due to a point mutation in the 14α-sterol demethylase (CYP51A) gene, which encodes the target of azole fungicides. Moreover, overexpression of CYP51B or multidrug resistance (MDR) gene is supposedly related to the mechanism of azole resistance in A. fumigatus.

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Article Synopsis
  • * Researchers found that while the typical HIV-1 transcript (G1-form) has one G at the 5'-end, variants with more Gs (G2- and G3-forms) are also produced in infected cells and found in virus particles.
  • * Experiments showed that viruses produced exclusively with the G1-form had enhanced reverse transcription efficiency and that the G count significantly affects the production of cDNA intermediates necessary for successful viral replication.
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Objectives: The aim of the study was to describe the morbidity pattern of different diagnostic categories in insured cats in Japan by age, sex and breed.

Methods: The annual incidence rates of having at least one insurance claim were calculated overall and stratified by diagnosis, age, sex and breed using data from insured cats in the period April 2008 to March 2013.

Results: The overall annual incidence rate of having at least one insurance claim was 4632 (95% confidence interval 4608-4656) cats per 10,000 cat-years at risk.

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The association between breed, gender and age and cardiovascular disorders in the insured dog population in Japan was investigated, using multiple logistic regression analysis and data from 299,555 dogs insured between April 2010 and March 2011. The overall annual prevalence of cardiovascular disorder diagnosis was 2.1%.

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Monocyte and dendritic cell (DC) development was evaluated using in vivo BrdU pulse-chase analyses in rhesus macaques, and phenotype analyses of these cells in blood also were assessed by immunostaining and flow cytometry for comparisons among rhesus, cynomolgus, and pigtail macaques, as well as African green monkeys and humans. The nonhuman primate species and humans have three subsets of monocytes, CD14(+)CD16(-), CD14(+)CD16(+), and CD14(-)CD16(+) cells, which correspond to classical, intermediate, and nonclassical monocytes, respectively. In addition, there exist presently two subsets of DC, BDCA-1(+) myeloid DC and CD123(+) plasmacytoid DC, that were first confirmed in rhesus macaque blood.

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