Publications by authors named "Hiroki Kagawa"

A 42-year-old woman was admitted to our hospital because of lower abdominal pain and diarrhea. Although the initial symptoms and imaging findings were similar to those of acute enteritis, blood and ascites cultures led to the diagnosis of primary peritonitis caused by group A Streptococcus. In many cases, the disease rapidly deteriorates, and laparotomy is performed for the early diagnosis and to reduce the number of bacteria in the abdominal cavity.

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Selenium compounds such as methylseleninic acid (MSA) and sodium selenite (SS) have been widely evaluated as potential anti-cancer agents in the clinical setting. Primary effusion lymphoma (PEL) is a non-Hodgkin's B-cell lymphoma, associated with immunosuppressed individuals, such as post-transplant or AIDS patients. Kaposi's sarcoma-associated herpesvirus (KSHV) is the causative agent of PEL and Kaposi's sarcoma.

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The Sonic hedgehog (Shh) signaling pathway plays a crucial role in cell proliferation and differentiation via Patched1 (Ptc1), a 12-pass transmembrane receptor protein. The C-terminal cytoplasmic tail of Ptc1 can be cleaved to release the 7th intracellular domain (ICD7), whose function is still unclear. In this study, we found that the ICD7 fragment of Ptc1 associates with polyubiquitinated species.

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Primary effusion lymphoma (PEL), a subtype of non-Hodgkin's B-lymphoma, is an aggressive neoplasm caused by Kaposi's sarcoma-associated herpesvirus (KSHV) in immunosuppressed patients. Endoplasmic reticulum (ER) stress induces activation of the unfolded protein response (UPR), which induces expression of ER chaperones, which in turn decrease ER stress, leading to ER homeostasis. The UPR is necessary for not only ER homeostasis but also persistent infection by, and replication of, many viruses.

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The allyl sulfides, including diallyl sulfide (DAS), diallyl disulfide (DAD), and diallyl trisulfide (DAT), contained in garlic and members of the Allium family, have a variety of pharmacological activities. Therefore, allyl sulfides have been evaluated as potential novel chemotherapeutic agents. Here, we found that DAT inhibited nuclear factor-κB (NF-κB) signaling and induced apoptosis in primary effusion lymphoma (PEL), a subtype of non-Hodgkin's B-cell lymphoma caused by Kaposi's sarcoma-associated herpesvirus (KSHV).

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Primary effusion lymphoma (PEL) is a subtype of non-Hodgkin's B-cell lymphoma and is an aggressive neoplasm caused by Kaposi's sarcoma-associated herpesvirus (KSHV) in immunosuppressed patients. In general, PEL cells are derived from post-germinal center B-cells and are infected with KSHV. To evaluate potential novel anti-tumor compounds against KSHV-associated PEL, seven water-soluble fullerene derivatives were evaluated as potential drug candidates for the treatment of PEL.

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Background: Although it has received a degree of notoriety as a cause for antibiotic-associated enterocolitis (AAE), the role of methicillin resistant Staphylococcus aureus (MRSA) in the pathogenesis of this disease remains enigmatic despite a multitude of efforts, and previous studies have failed to conclude whether MRSA can cause AAE. Numerous cases of AAE caused by MRSA have been reported from Japan; however, due to the fact that these reports were written in the Japanese language and a good portion lacked scientific rigor, many of these reports went unnoticed.

Methods: We conducted a systematic review of pertinent literatures to verify the existence of AAE caused by MRSA.

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Sangivamycin, a structural analog of adenosine and antibiotic exhibiting antitumor and antivirus activities, inhibits protein kinase C and the synthesis of both DNA and RNA. Primary effusion lymphoma (PEL) is an aggressive neoplasm caused by Kaposi's sarcoma-associated herpesvirus (KSHV) in immunosuppressed patients and HIV-infected homosexual males. PEL cells are derived from post-germinal center B cells, and are infected with KSHV.

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Primary effusion lymphoma (PEL) is an aggressive neoplasm caused by Kaposi's sarcoma-associated herpesvirus (KSHV) in immunosuppressed patients and human immunodeficiency virus (HIV)-infected homosexual males. We evaluated the cytotoxic effects of heat shock protein 90 (HSP90) inhibitors on PEL cells. The HSP90 inhibitors geldanamycin (GA), 17(allylamino)-17-demethoxygeldanamycin (17-AAG), and radicicol dramatically inhibited cell proliferation and induced apoptosis of PEL cells through caspase activation.

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Background: Patched 1 (Ptc1) is a polytopic receptor protein that is essential for growth and differentiation. Its extracellular domains accept its ligand, Sonic Hedgehog, while the function of its C-terminal intracellular domain is largely obscure.

Principal Findings: In this study, we stably expressed human Ptc1 protein in HeLa cells and found that it is subjected to proteolytic cleavage at the C-terminus, resulting in the generation of soluble C-terminal fragments.

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BAG-6/Scythe/BAT3 is a ubiquitin-like protein that was originally reported to be the product of a novel gene located within the human major histocompatibility complex, although the mechanisms of its function remain largely obscure. Here, we demonstrate the involvement of BAG-6 in the degradation of a CL1 model defective protein substrate in mammalian cells. We show that BAG-6 is essential for not only model substrate degradation but also the ubiquitin-mediated metabolism of newly synthesized defective polypeptides.

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