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101.
Human spumavirus replication in human cells 总被引:2,自引:0,他引:2
It was previously reported that the replication of the human syncytium-forming virus (HSFV), a spumavirus, occurred only in fibroblast-like cell lines (human fetal diploid lung #645 [HFDL]) but not in epithelial-like lines (recovered amnion) [RA]. Factors that may be involved in such a phenomenon were the subject of this investigation. While both permissive (HFDL) and nonpermissive (RA) cell lines supported the replication of several representative animal viruses and adsorbed HSFV equally well, immunofluorescent staining of HSFV antigens revealed markedly fewer fluorescing cells in nonpermissive cultures. Infectious center assays of infected nonpermissive cells indicated the formation of significantly fewer infectious centers. The rate of DNA synthesis was markedly greater in the permissive cell lines. In addition, in the permissive cell line, the amount of proviral DNA revealed by the Hirt procedure and isopycnic banding in CsCl was significantly increased and was infectious as determined by the calcium phosphate-DMSO transfection assay. These results indicate that resistance of HSFV infection in nonpermissive cell cultures is probably an intracellular event. 相似文献
102.
Baculovirus gp64 envelope glycoprotein is a major component of the envelope of the budded virus and is involved in virus entry into the host cells by endocytosis. To investigate the cell-surface molecules important for infection of baculovirus into mammalian cells, we constructed a recombinant baculovirus, Ac64-CAluc, which has gp64 and luciferase genes under the polyhedrin and the CAG promoter, respectively. For controls, we constructed recombinant viruses possessing vesicular stomatitis virus (VSV) G protein, mouse hepatitis virus (MHV) S protein, or green fluorescent protein (GFP) gene under the polyhedrin promoter and the luciferase gene under the CAG promoter (AcVSVG-CAluc, AcMHVS-CAluc, and AcGFP-CAluc). Treatment of HepG2 cells with phospholipase C markedly reduced the reporter gene expression by Ac64-CAluc or AcVSVG-CAluc in a dose-dependent manner, whereas AcMHVS-CAluc was shown to be resistant to the treatment. Inhibition with purified lipids and susceptibility to the mutant CHO hamster cell lines deficient in phospholipids synthesis suggest that the interaction of gp64 and phospholipids on the cell surface might play an important role in baculovirus infection into mammalian cells. 相似文献
103.
Hitoshi Nishimura Masashi Emoto Kenji Hiromatsu Shunsuke Yamamoto Keiko Matsuura Hiroshi Gomi Toshio Ikeda Shigeyoshi Itohara Yasunobu Yoshikai 《European journal of immunology》1995,25(5):1465-1468
The secretion of tumor necrosis factor (TNF)-α from macrophages is regulated by both priming and triggering signals. We found that macrophages from mice lacking γδ T cells [T cell receptor (TCR) δ?/- mice], which lack the gene encoding the δ chain, produced only small amounts of TNF-α in response to lipopolysaccharide (LPS) and showed a reduced level of expression of CD14. Pre-incubation of macrophages from TCR δ-/- mice with γδ T cells from their TCR δ+/- littermates restored their capacity to produce TNF-α in response to LPS. The priming activity of γδ T cells was in part inhibited by neutralizing anti-interferon (IFN)-γ monoclonal antibodies. Collectively, these results suggest that γδ T cells play a role in priming macrophages to a steady state of activation via IFN-γ secretion, which allows them to produce TNF-α when exposed to LPS. 相似文献
104.
S Yachiku S Kaneko T Matsuura T Akiyama T Kurita 《Hinyokika kiyo. Acta urologica Japonica》1985,31(3):545-551
Tsumura Hachimijiogan, 7.5 g a day, was administered to 30 patients with benign prostatic hypertrophy (BPH). Clinical effects were estimated based on subjective symptoms and objective findings obtained by uroflowmetry. Twenty patients (66.7%) showed improvement of subjective symptoms and 14 patients (46.7%) showed good response in uroflowmetry. An improvement of overall clinical efficacy was observed in 21 patients (70%). These results were better than those obtained with 5.0 g a day doses of Tsumura Hachimijiogan. No significant relation between the "Sho" in Chinese medicine and the clinical effects of Hachimijiogan was detected. No side effects or abnormal laboratory data were found in any of these 30 patients. 相似文献
105.
106.
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
107.
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
108.
Alex M. Hollenberg Noorullah Maqsoodi Amy Phan Aric Huber Ayodeji Jubril Avionna L. Baldwin Noriaki Yokogawa Roman A. Eliseev Addisu Mesfin 《The spine journal》2021,21(7):1205-1216
BACKGROUND CONTEXTBack and neck pain secondary to disc degeneration is a major public health burden. There is a need for therapeutic treatments to restore intervertebral disc (IVD) composition and function.PURPOSETo quantify ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression in IVD specimens collected from patients undergoing surgery for disc degeneration, to correlate ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression in IVD specimens to the 5-level Pfirrmann MRI grading system, and to compare ALK3, BMP-2, pSMAD1/5/8 and MMP-13 expression between cervical and lumbar degenerative disc specimens.STUDY DESIGNAn immunohistochemical study assessing ALK3, BMP-2, pSMAD1/5/8, and MMP-13 expression levels in human control and degenerative IVD specimens.METHODSHuman IVD specimens were collected from surgical patients who underwent discectomy and interbody fusion at our institution between 1/2015 and 8/2017. Each patient underwent MRI prior to surgery. The degree of disc degeneration was measured according to the 5-level Pfirrmann MRI grading system. Patients were categorized into either the 1) control group (Pfirrmann grades I-II) or 2) degenerative group (Pfirrmann grades III-V). Histology slides of the collected IVD specimens were prepared and immunohistochemical staining was performed to assess ALK3, BMP-2, pSMAD1/5/8, and MMP-13 expression levels in the control and degenerative specimens. Expression levels were also correlated to the Pfirrmann criteria. Lastly, the degenerative specimens were stratified according to their vertebral level and expression levels between the degenerative lumbar and cervical discs were compared.RESULTSFifty-two patients were enrolled; however, 2 control and 2 degenerative patients were excluded due to incomplete data sets. Of the remaining 48 patients, there were 12 control and 36 degenerative specimens. Degenerative specimens had increased expression levels of BMP-2 (p=.0006) and pSMAD1/5/8 (p<.0001). Pfirrmann grade 3 (p=.0365) and grade 4 (p=.0008) discs had significantly higher BMP-2 expression as compared to grade 2 discs. Pfirrmann grade 4 discs had higher pSMAD1/5/8 expression as compared to grade 2 discs (p<.0001). There were no differences in ALK3 or MMP-13 expression between the control and degenerative discs (p>.05). Stratifying the degenerative specimens according to their vertebral level showed no significant differences in expression levels between the lumbar and cervical discs (p>.05).CONCLUSIONSBMP-2 and pSMAD1/5/8 signaling activity was significantly upregulated in the human degenerative specimens, while ALK3 and MMP-13 expression were not significantly changed. The expression levels of BMP-2 and pSMAD1/5/8 correlate positively with the degree of disc degeneration measured according to the Pfirrmann MRI grading system.CLINICAL SIGNIFICANCEBMP-SMAD signaling represents a promising therapeutic target to restore IVD composition and function in the setting of disc degeneration. 相似文献
109.
Tsukumi TONDOKORO Akinori NAKATA Yasumasa OTSUKA Nobuyuki YANAGIHARA Ayumi ANAN Hiromi KODAMA Noriaki SATOH 《Industrial health》2021,59(2):128
Although participatory workplace improvement programs are known to provide favorable effects on high stress occupations like nursing, no studies have confirmed its effect using biomarkers. The aim of this study was to determine whether a participatory workplace improvement program would decrease stress-related symptoms as evaluated by biomarkers and self-reported stress among hospital nurses. Three actions to alleviate job stress, which were determined through focus group interviews and voting, were undertaken for two months. A total of 31 female Japanese nurses underwent measurement of inflammatory markers, autonomic nervous activity (ANA), and perceived job stress (PJS) at three-time points; before the program (T1), within a week after the completion of the program (T2), and three months after the program (T3). A series of inflammatory markers (Interferon-γ, Interleukin (IL)-6, and IL-12/23p40) decreased significantly at T2, and IL-12/23p40 and IL-15 significantly decreased at T3 compared to T1, while ANA and PJS remained unchanged. Our participatory program exerted beneficial effects in reducing inflammatory responses, but not for ANA and PJS. Further investigations with a better study design, i.e., a randomized controlled trial, and a larger sample size are warranted to determine what exerted beneficial effects on inflammatory markers and why other outcomes remained unchanged. 相似文献
110.
We have developed a breast-conserving surgery consisting of quadrantectomy and regional lymph node dissection and immediate
volume replacement using lateral tissue flap (LTF). The quadrantectomy was employed on the basis of segmental anatomy of the
duct lobular system in which breast carcinoma originates. Lateral skin incision was performed from the apex of mid-axillary
line to the inframammary fold, without removing the skin overlying the tumor. In the early period of breast reconstruction
embraced latissmus dorsi flap (LDF) for 10 patients (reconstruction was not performed on 35 patients), but in the late period
we employed LTF for 56 patients. Four of the 101 patients developed ipsilateral breast cancer during a mean follow-up period
of 48 months, but none died of breast cancer. Among the 56 patients with LTF replacement no patient developed ipsilateral
breast cancer. Fairly good cosmetic outcome was obtained in the patients who underwent the immediate volume replacement. Breast-conserving
surgeries are reviewed, and the surgical procedure using LTF for immediate volume replacement is described. 相似文献