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31.
Hideo Kunisada Yasuo Yuki Shuji Kondo Ken-ichi Goto 《Macromolecular chemistry and physics.》1993,194(5):1323-1334
Monomers containing several octadecyl groups, e.g., 2-isopropenyl-4,6-bis(octadecylamino)-1,3,5-triazine ( 2 ), 2-dioctadecylamino-4-isopropenyl-6-octadecylamino-1,3,5-triazine ( 3 ) and 2,4-bis(dioctadecylamino)-6-isopropenly-1,3,5-triazine ( 4 ) were prepared by the alkylation reaction of 2,4-diamino-6-isopropenyl-1,3,5-triazine ( 1 ) with 1-bromooctadecane in the presence of sodium hydride. In the free-radical homopolymerization of these monomers, the polymer yield of 3 was lower than that of 2 due to a decrease in the ceiling temperature, and the polymerization of 4 did not proceed. Copolymerizations of these monomers with styrene or methyl methacrylate were carried out and the monomer reactivity ratios (r1 and r2) were determined. The monomer reactivity decreased with increasing the number of octadecyl groups in the monomers. Crystallinity of the octadecyl side chains in the resulting comb-like polymers was evaluated by differential scanning calorimetry. 相似文献
32.
Kazuya Kusama Mayuko Miyagawa Koichiro Ota Naoko Kuwabara Kaori Saeki Yuki Ohnishi Yasuhiro Kumaki Tomoyasu Aizawa Toyokazu Nakasone Shigemi Okamatsu Hiroaki Miyaoka Kazuhiro Tamura 《Nutrients》2021,13(1)
The androgens testosterone and dihydrotestosterone (DHT) are essential for a variety of systemic functions in mature males. Alteration of these hormones results in late-onset hypogonadism (LOH) and benign prostate hyperplasia (BPH). The fruit bodies of fungi of the genus Cordyceps have been regarded as folk medicine or health food with tonic and antifatigue effects. The extract from the fruit body of Cordyceps militaris parasitizing Samia cynthia ricini (CM) was evaluated as a novel-candidate natural product for ameliorating male andropause symptoms. To explore the effects of CM on LOH and BPH, CM was applied to rat models and cultured testicular cells and prostate cells. The concentrations of androgens in the serum and culture media were determined by ELISA. Expression of steroidogenic enzymes and androgen-related genes was evaluated by qPCR, and prostatic cell proliferation was assessed with the cell-viability assay. CM maintained the serum levels of testosterone and DHT, but inhibited testosterone-induced prostate hypertrophy. CM also increased the secretion of testosterone and DHT by primary testicular cells, with no changes in the mRNA expression of steroidogenic enzymes, but decreased the growth of prostatic cell lines. Our data suggest that CM could improve both LOH and BPH in males. 相似文献
33.
34.
Taiki Matsunaga Yuki Kamachi Koichi Kinoshita Tetsuya Sakamoto Takuaki Yamamoto 《The Journal of arthroplasty》2021,36(2):429-433
BackgroundCurved periacetabular osteotomy (CPO) is performed via an anterior approach without detachment of the hip abductor muscles. This study aimed to evaluate the abductor muscle status shortly after CPO on magnetic resonance imaging (MRI).MethodsWe prospectively evaluated 38 hips in 38 patients 1 week and 3 months after CPO between October 2017 and July 2019. The status of the abductor muscles was assessed on MRI using the following criteria: grade 0, normal; grade I, strain/edema; grade II, partial tear; and grade III, complete tear. We also evaluated associations between muscle status and patients’ characteristics.ResultsOne week after CPO, the gluteus maximus was classified as grade 0 in all patients. The gluteus medius was grade 0 in 84.2% of patients and grade I in 15.8%. The gluteus minimus was grade I in 55.3% of patients and grade II in 44.7%. Three months after CPO, both the gluteus maximus and gluteus medius were grade 0 in all patients, while the gluteus minimus was still grade I in 47.4%. There were no significant differences between patients with a grade 0 and grade I gluteus minimus at 3 months after CPO in patients’ characteristics (age and body mass index) or clinical scores (Harris Hip Score and Japanese Orthopedics Association score).ConclusionBoth the gluteus minimus and medius showed abnormal appearances on MRI 1 week after CPO, whereas only the gluteus minimus showed abnormalities 3 months after CPO. This abductor muscle status did not affect the postoperative Harris Hip Score or Japanese Orthopedics Association score. 相似文献
35.
Yuki Bekki Josep Marti Takeo Toshima Sara Lewis Amita Kamath Pamela Argiriadi William Simpson Lucas Facciuto Rahul S. Patel Ganesh Gunasekaran Edward Kim Thomas D. Schiano Marcelo E. Facciuto 《Surgery》2021,169(5):1044-1051
BackgroundPortal vein embolization before liver resection is considered the therapy of choice for patients with inadequate future liver remnants. The concept of radioembolization with Yttrium-90 to achieve the same goal has limited data.MethodsWe retrospectively compared patients who underwent portal vein embolization and Yttrium-90 lobectomy before resection of hepatocellular carcinoma in patients with chronic liver disease.ResultsSeventy-three patients underwent portal vein embolization and 22 patients underwent Yttrium-90. Forty-seven percent of patients before portal vein embolization required additional procedures for tumor control, and 27% of patients after Yttrium-90 required additional procedure to mainly induce further hypertrophy. Both therapies achieved the goal of future liver remnants >40%, but the degree of hypertrophy was significantly higher in Yttrium-90 patients (63% for Yttrium-90, 36% for portal vein embolization, P < .01). Tumor response was significantly better with Yttrium-90, achieving complete response in 50% of patients. Resectability rate was higher after portal vein embolization (85% for portal vein embolization, 64% for Yttrium-90, P = .03). Tumor progression was the most common reason precluding surgery. Complete tumor control was the reason not to pursue surgery in 18% of patients after Yttrium-90.ConclusionBoth preoperative portal vein embolization and Yttrium-90, increases liver resectability rates by inducing hypertrophy of future liver remnants in patients with hepatocellular carcinoma and chronic liver disease. Yttrium-90 lobectomy achieved better tumor control and provided more time to assess therapy response, optimizing the indication for surgery. 相似文献
36.
Yuki Ohya Masayoshi Tasaki Shintaro Hayashida Nobuhiro Katayama Toru Tsuchida Kazumi Kuriwaki Mitsuharu Ueda Yukihiro Inomata 《Transplantation proceedings》2021,53(4):1313-1316
BackgroundCarpal tunnel syndrome is the most common compression syndrome of the peripheral nerve. Transthyretin amyloidosis and dialysis-related β2-microglobulin amyloidosis are known causes of carpal tunnel syndrome.Case ReportA Japanese woman showed carpal tunnel syndrome 16 years after a domino liver transplantation (DLT) from the donor with hereditary transthyretin amyloidosis. DLT indication was congenital extrahepatic portosystemic shunt, and the patient had been put on maintenance hemodialysis because of chronic kidney disease 6 years before DLT. Moreover, the amyloid precursor protein of the patient was histologically confirmed not to be β2-microglobulin, but transthyretin.ConclusionsThe existence of amyloid was speculated when the patient who underwent DLT from hereditary transthyretin amyloidosis showed carpal tunnel syndrome. Additionally, elucidating the amyloid precursor protein when the patient has another cause of amyloidosis is necessary. 相似文献
37.
Yuki Matsushita Angel Ka Yan Chu Wanida Ono Joshua D Welch Noriaki Ono 《Journal of bone and mineral research》2021,36(6):1145-1158
Bone marrow houses a multifunctional stromal cell population expressing C-X-C motif chemokine ligand 12 (CXCL12), termed CXCL12-abundant reticular (CAR) cells, that regulates osteogenesis and adipogenesis. The quiescent pre-adipocyte-like subset of CXCL12+ stromal cells (“Adipo-CAR” cells) is localized to sinusoidal surfaces and particularly enriched for hematopoiesis-supporting cytokines. However, detailed characteristics of these CXCL12+ pre-adipocyte-like stromal cells and how they contribute to marrow adipogenesis remain largely unknown. Here we highlight CXCL12-dependent physical coupling with hematopoietic cells as a potential mechanism regulating the adipogenic potential of CXCL12+ stromal cells. Single-cell computational analyses of RNA velocity and cell signaling reveal that Adipo-CAR cells exuberantly communicate with hematopoietic cells through CXCL12-CXCR4 ligand-receptor interactions but do not interconvert with Osteo-CAR cells. Consistent with this computational prediction, a substantial fraction of Cxcl12-creER+ pre-adipocyte-like cells intertwines with hematopoietic cells in vivo and in single-cell preparation in a protease-sensitive manner. Deletion of CXCL12 in these cells using Col2a1-cre leads to a reduction of stromal-hematopoietic coupling and extensive marrow adipogenesis in adult bone marrow, which appears to involve direct conversion of CXCL12+ cells to lipid-laden marrow adipocytes without altering mesenchymal progenitor cell fates. Therefore, these findings suggest that CXCL12+ pre-adipocyte-like marrow stromal cells prevent their premature differentiation by maintaining physical coupling with hematopoietic cells in a CXCL12-dependent manner, highlighting a possible cell-non-autonomous mechanism that regulates marrow adipogenesis. © 2021 American Society for Bone and Mineral Research (ASBMR). 相似文献
38.
Wada Takehiko Ishimoto Takuji Nakaya Izaya Kawaguchi Takehiko Sofue Tadashi Shimizu Sayaka Kurita Noriaki Sasaki Sho Nishiwaki Hiroki Koizumi Masahiro Saito Shoji Nishibori Nobuhiro Oe Yuji Yoshida Mai Miyaoka Yoshitaka Akiyama Shin’ichi Itano Yuya Okazaki Masaki Ozeki Takaya Ichikawa Daisuke Oguchi Hideyo Kohsaka Satoshi Kosaka Shiho Kataoka Yuki Shima Hideaki Shirai Sayuri Sugiyama Kazuhiro Suzuki Tomo Son Daisuke Tanaka Tomomi Nango Eishu Niihata Kakuya Nishijima Yoko Nozu Kandai Hasegawa Midori Miyata Rei Yazawa Masahiko Yamamoto Yoshihiro Yamamoto Ryohei Shibagaki Yugo Furuichi Kengo Okada Hirokazu Narita Ichiei 《Clinical and experimental nephrology》2021,25(12):1277-1285
Clinical and Experimental Nephrology - 相似文献
39.
Go Anan Hiromichi Iwamura Jotaro Mikami Yuki Kohada Jun Ito Yasuhiro Kaiho Makoto Sato 《Translational andrology and urology》2021,10(2):775
BackgroundHolmium laser enucleation of the prostate (HoLEP) has been a widely utilized minimally invasive surgical procedure for benign prostate hyperplasia. The current study aimed to compare surgical outcomes and King’s Health Questionnaire (KHQ) assessment scores following HoLEP between younger men and those aged ≥75 years.MethodsThis prospective single-center study compared perioperative complications, postoperative urinary conditions, and KHQ scores (nine categories) between men aged ≥75 years (group A) and men aged <75 years (group B) before and 1, 3, and 6 months after surgery.ResultsA total of 100 patients were included for analysis (group A, n=38 and group B, n=62). No differences in patient backgrounds, perioperative complications, such as perioperative decrease in hemoglobin, postoperative fever, postoperative indwelling catheterization duration, or postoperative hospitalization duration, and KHQ were observed between both groups. Both groups showed significantly better International Prostate Symptom Scores, quality of life, maximum urinary flow rate, and postvoid residual volume 1, 3, and 6 months after HoLEP compared to their respective preoperative levels (P<0.01). Regarding KHQ categories, both groups showed significantly better general health perceptions, impact on life, emotions, and sleep/energy 1 month after HoLEP; role limitations, physical limitations, and social limitations 3 months after HoLEP; and personal relationships and incontinence severity measures 6 months after HoLEP compared to their respective preoperative levels (P<0.05).ConclusionsHoLEP could be safe and effective even for men aged ≥75 years, comparing complications, urinary condition, and KHQ scores. 相似文献
40.
Yuki Tajika Tohru Murakami Mahito Sato Fumitaka Kubota Hiroshi Yorifuji 《Developmental dynamics》2008,237(7):1886-1892
Vesicle-associated membrane protein 2 (VAMP2) is a member of the SNARE family of proteins that regulate the intracellular vesicle fusion process. This study investigated the developmental expression of VAMP2 in the rat embryo. In the trunk, VAMP2 was primarily found in the heart on embryonic day (E) 10. On E12.5, VAMP2 expression was found in nerve fibers, somites, and heart. In somites, epithelial cells in the dorsomedial lip, and elongated myoblasts in myotome were positive for VAMP2. On E16.5, VAMP2 was expressed in the heart, nerve fibers, and skeletal muscles. In skeletal muscles, multinuclear myotubes were positive for VAMP2. In the head, where muscles are derived both from somitic and non-somitic origin, VAMP2 was found in myotubes of the extrinsic ocular muscles and masseter muscle on E16.5. These findings suggest the involvement of VAMP2 in the development of skeletal muscles of somitic and non-somitic origins. 相似文献