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Hori Hiroki Ohta Asuka Matsui Honami Yano Kanako Morita-Tominaka Miyuki Linn Zayar Masumoto Daisuke Okumura Yosuke Okamura Satoshi Kurihara Kosuke Hayakawa Akira Rikiishi Takeshi Kobayashi Kyoko 《International journal of clinical oncology / Japan Society of Clinical Oncology》2022,27(1):245-252
International Journal of Clinical Oncology - The practice of cancer diagnosis disclosure to children has been changed with the times. The regulations of clinical trials in the 2000s might change... 相似文献
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Ryoma Tsuchiya Aino Kaneshima Masakazu Kobayashi Maki Yamazaki Yoko Takasu Hideki Sezutsu Yoshiaki Tanaka Akira Mizoguchi Kunihiro Shiomi 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(1)
Diapause represents a major developmental switch in insects and is a seasonal adaptation that evolved as a specific subtype of dormancy in most insect species to ensure survival under unfavorable environmental conditions and synchronize populations. However, the hierarchical relationship of the molecular mechanisms involved in the perception of environmental signals to integration in morphological, physiological, behavioral, and reproductive responses remains unclear. In the bivoltine strain of the silkworm Bombyx mori, embryonic diapause is induced transgenerationally as a maternal effect. Progeny diapause is determined by the environmental temperature during embryonic development of the mother. Here, we show that the hierarchical pathway consists of a γ-aminobutyric acid (GABA)ergic and corazonin signaling system modulating progeny diapause induction via diapause hormone release, which may be finely tuned by the temperature-dependent expression of plasma membrane GABA transporter. Furthermore, this signaling pathway possesses similar features to the gonadotropin-releasing hormone (GnRH) signaling system for seasonal reproductive plasticity in vertebrates.To ensure survival under unfavorable environmental conditions and synchronize populations, most insect species enter diapause, which is a seasonal adaptation that evolved as a specific subtype of dormancy (1, 2). Diapause is not a passive response to changing conditions but rather an actively induced state that precedes adverse natural situations. Therefore, this diapause phenotype is accompanied by changes in energy metabolism or storage to improve cold/stress tolerance in later life stages, or progeny via reproductive switch (3). Although it has been generally suggested that brain/neuroendocrine systems are associated with this seasonal reproductive plasticity in both vertebrates and invertebrates (3, 4), the hierarchical relationship of the molecular mechanisms involved in the perception of environmental signals to integration into morphological, physiological, behavioral, and reproductive responses, known as the diapause syndrome, remains unclear (3).The silkworm Bombyx mori is a typical insect that arrests normal development during early embryogenesis, which is accompanied by metabolic changes in diapause (5, 6). The development of diapause-destined embryos is arrested during the G2 cell cycle stage immediately after the formation of the cephalic lobe and telson and sequential segmentation of the mesoderm (7). The bivoltine strain of B. mori has two generations per year, and progeny diapause is transgenerationally induced as a maternal effect and is determined by the environmental temperature, photoperiod, and nutrient conditions during embryonic and larval development of the mother (5, 6). The temperature signal during the mother’s embryonic development predominantly affects diapause determination, even if silkworms of the bivoltine Kosetsu strain are exposed to all cases of photoperiods during embryonic and larval development. In the Kosetsu strain, when eggs are incubated at 25 °C under continuous darkness, the resultant female moths (25DD) lay diapause eggs in almost all cases. In contrast, incubation of eggs at 15 °C in dark condition results in moths (15DD) that lay nondiapause eggs in almost all cases (6).Embryonic diapause is induced by the diapause hormone (DH) signaling pathway, which consists of highly sensitive and specific interactions between a neuropeptide, DH, and DH receptor (DHR) (6, 8). DH is exclusively synthesized in seven pairs of neurosecretory cells (DH-PBAN–producing neurosecretory cells [DHPCs]) located within the subesophageal ganglion (SG) in the mother’s generation (6). DH is released into the hemolymph during pupal–adult development and acts on the DHR, which belongs to the G protein-coupled receptors (GPCRs) (9). DH levels in the hemolymph are higher in the 25DD than 15DD pupae in the middle of pupal–adult development when the developing ovaries are sensitive to DH (6). Furthermore, the embryonic Bombyx TRPA1 ortholog (BmTRPA1) acts as a thermosensitive channel that is activated at temperatures above ∼21 °C and affects diapause induction through DH release (10). However, there remain questions about the thermal information that is received by BmTRPA1 and linked to DH signaling to induce diapause.From the 1950s, it has been suggested that the DH release was controlled by signals derived from certain region(s) in the brain based on surgical experiments, such as midsagittal bisection or transection (11–13). Especially, the operation in nondiapause producers changed them to diapause producers while transection of the protocerebrum had no effect on the diapause producers. These surgical results suggested the involvement of the protocerebrum in the inhibitory control of DH secretion (12, 14). Furthermore, the accumulation of the ovarian 3-hydroxykynurenine (3-OHK) pigment that accompanies the diapause syndrome was affected by injection with γ-aminobutyric acid (GABA) and the plant alkaloid picrotoxin (PTX), which is a widely used ionotropic GABA and glycine receptor antagonist (15, 16), and the selective ionotropic GABA receptor (GABAR) antagonist bicuculline. This suggests that a GABAergic neurotransmission via ionotropic GABAR is involved in DH secretion, which may be active in nondiapause producers but inactive in diapause producers throughout the pupal–adult development (14, 17). In general, ionotropic GABAR is composed of homo- or hetero-pentameric subunits. All known GABAR subunits display a similar structural scheme, with a large N-terminal extracellular domain involved in the formation of a ligand-binding pocket and a pore domain made of four transmembrane alpha-helices (TM1–TM4) (16, 18). Four homologous sequences of the ionotropic GABAR subunit genes were identified as RDL, LCCH3, GRD, and a GRD-like sequence named 8916 in various insects (19). However, the in vivo physiological roles of both signals derived from the brain and the GABAergic pathway in diapause induction have not been previously investigated.Corazonin (Crz) is an undecapeptide neurohormone sharing a highly conserved amino acid (a.a.) sequence across insect lineages and is involved in different physiological functions, such as heart contraction (20), stress response (21, 22), various metabolic activities (23–25), female fecundity (26), melanization of locust cuticles (27), regulation of ecdysis (28, 29), and control of caste identity (30). Moreover, Crz belongs to the gonadotropin-releasing hormone (GnRH) superfamily alongside adipokinetic hormone (AKH) and AKH/Crz-related peptide (ACP). Duplicates of an ancestral GnRH/Crz signaling system occurred in a common ancestor of protostomes and deuterostomes through coevolution of the ligand receptor (31, 32).Herein, we demonstrated that the hierarchical pathway consists of a GABAergic and Crz signaling system modulating progeny diapause induction by acting on DH release. We propose that the PTX-sensitive GABAergic signal may act to chronically suppress Crz release in dorsolateral Crz neurons (under nondiapause conditions) and that diapause conditions (or PTX injection) inhibits GABAergic signaling, resulting in accelerated Crz release, which in turn induces DH release. GABA signaling may be finely tuned by the temperature-dependent expression of the plasma membrane GABA transporter (GAT), which differs between the 25DD and 15DD conditions. Furthermore, this signaling pathway possesses similar features to the GnRH signaling system with respect to seasonal reproductive plasticity in vertebrates. 相似文献
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Mana Kogure Naho Tsuchiya Akira Narita Takumi Hirata Naoki Nakaya Tomohiro Nakamura Atsushi Hozawa Takehito Hayakawa Nagako Okuda Naoko Miyagawa Aya Kadota Takayoshi Ohkubo Yoshitaka Murakami Kiyomi Sakata Katsuyuki Miura Akira Okayama Tomonori Okamura Hirotsugu Ueshima 《Journal of epidemiology / Japan Epidemiological Association》2021,31(2):119
BackgroundMajor reasons for long-term care insurance certification in Japan are stroke, dementia, and fracture. These diseases are reported to be associated with calcium intake. This study examined the association between calcium intake and impaired activities of daily living (ADL) using the data from NIPPON DATA90, consisting of representative sample of the Japanese population.MethodsA population-based nested case-control study was performed. A baseline survey was conducted in 1990, followed by ADL surveys of individuals ≥65 years old in 2000. Individuals with impaired ADL and selected age- and sex-matched controls were then identified. We obtained 132 pairs. Calcium intake was energy-adjusted using the residual method. The association between calcium intake and impaired ADL was examined using conditional logistic regression models. To assess the accuracy of the estimates, we conducted bootstrap analyses.ResultsThe adjusted odds ratios (ORs) for impaired ADL compared with the group with a calcium intake of <476 mg/day were 0.72 (95% confidence interval [CI], 0.37–1.40) for the 476–606 mg/day group and 0.44 (95% CI, 0.21–0.94) for the ≥607 mg/day group in 2000 (P for linear trend = 0.03). After the bootstrap analyses, the inverse relationship unchanged (median OR per 100-mg rise in calcium intake, 0.87 [1,000 resamplings]; 95% CI, 0.76–0.97).ConclusionsAfter bootstrap analyses, calcium intake was inversely associated with impaired ADL 10 years after the baseline survey.Key words: bootstrap analyses, calcium intake, impaired activities of daily living, nested case-control study, NIPPON DATA90 相似文献
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Comprehensive analysis of gene expression of isolated pancreatic islets during pretransplant culture
Junichiro Haga Naoya Sato Takayuki Anazawa Takashi Kimura Akira Kenjo Mitsukazu Gotoh Shigeru Marubashi 《Fukushima journal of medical science》2021,67(1):17
Background: The aim of this study was to investigate the effect of pretransplant culture on the survival of pancreatic islet grafts, and to determine the biological characteristics of isolated islets during pretransplant culture. Methods: The survival of islets from Wistar rats, transplanted to diabetic C57BL/B6 mice, was compared between fresh islets and cultured islets. A comprehensive gene expression analysis was employed to investigate biological processes during pretransplant culture, and in vitro validation studies were performed. Results: Survival of cultured xenografts was significantly prolonged as compared to that of fresh islets (fresh: 12.5 ± 1.9 days, 1-day cultured: 16.0 ± 1.3 days (p= 0.017), 3-day cultured: 17.0 ± 2.6 days (p= 0.014)). Comprehensive gene expression analysis identified significant upregulation of annotated functions associated with inflammation in cultured groups. Six proinflammatory genes, including heme oxygenase 1 (HO-1) and IL-6, were significantly upregulated during culture. Validation studies revealed significantly higher levels of IL-6 in the supernatant of cultured islets and HO-1 in the cultured islets when compared with fresh islets. Conclusion: Transplantation of cultured islets induced significant but minimal prolongation of graft survival in xenogeneic combinations. Comprehensive analysis of gene expression in cultured islets showed biological processes associated with proinflammation during culture. 相似文献
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Ota Yumiko Takahari Daisuke Suzuki Takeshi Osumi Hiroki Nakayama Izuma Oki Akira Wakatsuki Takeru Ichimura Takashi Ogura Mariko Shinozaki Eiji Suenaga Mitsukuni Chin Keisho Yamaguchi Kensei 《Cancer chemotherapy and pharmacology》2020,85(2):265-272
Cancer Chemotherapy and Pharmacology - In the ATTRACTION-2 trial, nivolumab significantly improved the survival of advanced gastric cancer patients. The pretreatment neutrophil-to-lymphocyte ratio... 相似文献