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51.
Yukiko Hori Yuji Nagai Koki Mimura Tetsuya Suhara Makoto Higuchi Sebastien Bouret Takafumi Minamimoto 《PLoS biology》2021,19(7)
It has been widely accepted that dopamine (DA) plays a major role in motivation, yet the specific contribution of DA signaling at D1-like receptor (D1R) and D2-like receptor (D2R) to cost–benefit trade-off remains unclear. Here, by combining pharmacological manipulation of DA receptors (DARs) and positron emission tomography (PET) imaging, we assessed the relationship between the degree of D1R/D2R blockade and changes in benefit- and cost-based motivation for goal-directed behavior of macaque monkeys. We found that the degree of blockade of either D1R or D2R was associated with a reduction of the positive impact of reward amount and increasing delay discounting. Workload discounting was selectively increased by D2R antagonism. In addition, blocking both D1R and D2R had a synergistic effect on delay discounting but an antagonist effect on workload discounting. These results provide fundamental insight into the distinct mechanisms of DA action in the regulation of the benefit- and cost-based motivation, which have important implications for motivational alterations in both neurological and psychiatric disorders.Using quantitatively controlled pharmacological manipulations, this study teases apart the role of D1- and D2-like dopamine receptors in motivation and goal-directed behavior in monkeys, revealing complementary roles of two dopamine receptor subtypes in the computation of the cost/benefit trade-off to guide action. 相似文献
52.
Nakano Ryohei Morita Taiki Okamoto Yuta Fujiwara Ayaka Yamanaka Takehiko Adachi-Hagimori Tetsuya 《BioControl》2021,66(3):407-418
BioControl - Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae) is a zoophytophagous predator that feeds on plants as well as prey. Several non-crop host plant species have been used to maintain... 相似文献
53.
Kimiko Izumo Masahisa Horiuchi Masaharu Komatsu Kohji Aoyama Kenjiro Bandow Tetsuya Matsuguchi 《Free radical research》2013,47(10):922-931
Dehydroepiandrosterone (DHEA), a reversible inhibitor of glucose-6-phosphate dehydrogenase (G6PD), is increasingly taken as an antioxidative and anti-ageing supplement. This study investigated the effects of DHEA on the expression of G6PD and on the state of oxidative stress in a human promyelocytic leukaemia cell line, HL60, during the differentiation to neutrophil-like cell. This study differentiated HL60 with dimethyl sulfoxide (DMSO) in the presence (DMSO-HL60/DHEA) or absence (DMSO-HL60) of DHEA. During the differentiation, activity, mRNA and protein levels of G6PD were increased. DHEA increased these levels further. DHEA by itself suppressed the production of superoxide from DMSO-HL60 upon stimulation with phorbol myristate acetate (PMA). However, DMSO-HL60/DHEA stimulated with PMA in the absence of DHEA produced superoxide and 8-oxo-deoxyguanosine more than PMA-stimulated DMSO-HL60. After addition of H2O2, the ratio of reduced glutathione to oxidized glutathione was lower in DMSO-HL60/DHEA than in DMSO-HL60. These findings indicate that DHEA acts both as an antioxidant and as a pro-oxidant. 相似文献
54.
Yoshihiro Nishino Shigekazu Takemura Yukiko Minamiyama Kazuhiro Hirohashi Tetsuya Ogino Masayasu Inoue 《Free radical research》2013,47(4):373-379
Vancomycin hydrochloride (VCM), a glycopeptide antibiotic, has a broad spectrum against methicillin-resistant Staphylococcus aureus (MRSA). As it is known to induce renal dysfunction, the dose and the duration of its administration are limited. Moreover, the mechanism of VCM-induced renal dysfunction remains to be unclear. To evaluate the involvement of free radical on VCM-induced renal dysfunction, we carried out analysis with a hexamethylenediamine-conjugated superoxide dismutase (AH-SOD) which rapidly accumulates in renal proximal tubule cells and inhibits oxidative injury of the kidney. Male Wistar rats (weighing 200-210 g) were intraperitonealy administered with 200 mg/kg of VCM twice a day for 7 days. AH-SOD 5 mg/kg/day was subcutaneously injected 5 min before every VCM injection. VCM induced renal injury dose-dependently. Biochemical analyses revealed that plasma levels of blood urea nitrogen and creatinine significantly increased in the VCM-treated group by an AH-SOD-inhibitable mechanism. VCM simultaneously elicited an increase of 8-OHdG levels and chemiluminescence intensity of free radical generation in the kidney. Histological examination revealed that VCM also elicited a marked destruction of glomeruli and necrosis of proximal tubules. AH-SOD inhibited these phenomena in the kidney. These results suggested that oxidative stress might underlie the pathogenesis of VCM-induced nephrotoxicity and targeting SOD and/or related antioxidants to renal proximal tubules might permit the administration of higher doses of VCM sufficient for eradication of MRSA without causing renal injury. 相似文献
55.
Yusuke Shiromoto Satomi Kuramochi-Miyagawa Akito Daiba Shinichiro Chuma Ami Katanaya Akiko Katsumata Ken Nishimura Manami Ohtaka Mahito Nakanishi Toshinobu Nakamura Koichi Yoshinaga Noriko Asada Shota Nakamura Teruo Yasunaga Kanako Kojima-Kita Daisuke Itou Tohru Kimura Toru Nakano 《RNA (New York, N.Y.)》2013,19(6):803-810
piRNA (PIWI-interacting RNA) is a germ cell–specific small RNA in which biogenesis PIWI (P-element wimpy testis) family proteins play crucial roles. MILI (mouse Piwi-like), one of the three mouse PIWI family members, is indispensable for piRNA production, DNA methylation of retrotransposons presumably through the piRNA, and spermatogenesis. The biogenesis of piRNA has been divided into primary and secondary processing pathways; in both of these MILI is involved in mice. To analyze the molecular function of MILI in piRNA biogenesis, we utilized germline stem (GS) cells, which are derived from testicular stem cells and possess a spermatogonial phenotype. We established MILI-null GS cell lines and their revertant, MILI-rescued GS cells, by introducing the Mili gene with Sendai virus vector. Comparison of wild-type, MILI-null, and MILI-rescued GS cells revealed that GS cells were quite useful for analyzing the molecular mechanisms of piRNA production, especially the primary processing pathway. We found that glycerol-3-phosphate acyltransferase 2 (GPAT2), a mitochondrial outer membrane protein for lysophosphatidic acid, bound to MILI using the cells and that gene knockdown of GPAT2 brought about impaired piRNA production in GS cells. GPAT2 is not only one of the MILI bound proteins but also a protein essential for primary piRNA biogenesis. 相似文献
56.
Masahiro Nakamori Tetsuya Takahashi Tomokazu Nishikawa Yu Yamazaki Takashi Kurashige Hirofumi Maruyama Koji Arihiro Masayasu Matsumoto 《PloS one》2013,8(11)
Background
Rimmed vacuoles (RVs) are round-oval cytoplasmic inclusions, detected in muscle cells of patients with myopathies, such as inclusion body myositis (IBM) and distal myopathy with RVs (DMRV). Granulovacuolar degeneration (GVD) bodies are spherical vacuoles containing argentophilic and hematoxyphilic granules, and are one of the pathological hallmarks commonly found in hippocampal pyramidal neurons of patients with aging-related neurodegenerative diseases, such as Alzheimer''s disease and Parkinson''s disease. These diseases are common in the elderly and share some pathological features. Therefore, we hypothesized that mechanisms of vacuolar formation in RVs and GVD bodies are common despite their role in two differing pathologies. We explored the components of RVs by immunohistochemistry, using antibodies for GVD markers.Methods
Subjects included one AD case, eight cases of sporadic IBM, and three cases of DMRV. We compared immunoreactivity and staining patterns for GVD markers. These markers included: (1) tau-modifying proteins (caspase 3, cyclin-dependent kinase 5 [CDK5], casein kinase 1δ [CK1δ], and c-jun N-terminal kinase [JNK]), (2) lipid raft-associated materials (annexin 2, leucine-rich repeat kinase 2 [LRRK2], and flotillin-1), and (3) other markers (charged multi-vesicular body protein 2B [CHMP2B] and phosphorylated transactive response DNA binding protein-43 [pTDP43]) in both GVD bodies and RVs. Furthermore, we performed double staining of each GVD marker with pTDP43 to verify the co-localization.Results
GVD markers, including lipid raft-associated proteins and tau kinases, were detected in RVs. CHMP2B, pTDP43, caspase 3, LRRK2, annexin 2 and flotillin-1 were detected on the rim and were diffusely distributed in the cytoplasm of RV-positive fibers. CDK5, CK1δ and JNK were detected only on the rim. In double staining experiments, all GVD markers colocalized with pTDP43 in RVs.Conclusions
These results suggest that RVs of muscle cells and GVD bodies of neurons share a number of molecules, such as raft-related proteins and tau-modifying proteins. 相似文献57.
58.
Yoshi Kawamoto Hiroyuki Takemoto Shoko Higuchi Tetsuya Sakamaki John A. Hart Terese B. Hart Nahoko Tokuyama Gay E. Reinartz Patrick Guislain Jef Dupain Amy K. Cobden Mbangi N. Mulavwa Kumugo Yangozene Serge Darroze Céline Devos Takeshi Furuichi 《PloS one》2013,8(3)
Bonobos (Pan paniscus) inhabit regions south of the Congo River including all areas between its southerly tributaries. To investigate the genetic diversity and evolutionary relationship among bonobo populations, we sequenced mitochondrial DNA from 376 fecal samples collected in seven study populations located within the eastern and western limits of the species’ range. In 136 effective samples from different individuals (range: 7–37 per population), we distinguished 54 haplotypes in six clades (A1, A2, B1, B2, C, D), which included a newly identified clade (D). MtDNA haplotypes were regionally clustered; 83 percent of haplotypes were locality-specific. The distribution of haplotypes across populations and the genetic diversity within populations thus showed highly geographical patterns. Using population distance measures, seven populations were categorized in three clusters: the east, central, and west cohorts. Although further elucidation of historical changes in the geological setting is required, the geographical patterns of genetic diversity seem to be shaped by paleoenvironmental changes during the Pleistocene. The present day riverine barriers appeared to have a weak effect on gene flow among populations, except for the Lomami River, which separates the TL2 population from the others. The central cohort preserves a high genetic diversity, and two unique clades of haplotypes were found in the Wamba/Iyondji populations in the central cohort and in the TL2 population in the eastern cohort respectively. This knowledge may contribute to the planning of bonobo conservation. 相似文献
59.
60.