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61.
A new temperate wood bamboo endemic to Vietnam is described and illustrated as Chimonocalamus bidoupensis N.H.Nghia & V.T.Tran. The new species is similar to C. baviensis in general appearance, but differs by its densely ciliate culms, culm sheaths that are concave at the apex with dense, white hairs on the abaxial surface of the sheath, and perfect florets 7–8 mm long.  相似文献   
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Nam  Jin-Sik  Park  Seo-Yeon  Lee  Seon-Ok  Lee  Hyo-Jeong  Jang  Hye-Lim  Rhee  Young Ha 《Molecular biology reports》2021,48(3):2173-2181
Molecular Biology Reports - The pawpaw tree has several beneficial effects. However, no studies have been conducted to address the mechanisms underlying the cytotoxic effects of pawpaw extracts...  相似文献   
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Background aimsMesenchymal stem/stromal cells (MSCs) are of interest for the treatment of graft-versus-host disease, autoimmune diseases, osteoarthritis and neurological and cardiovascular diseases. Increasing numbers of clinical trials emphasize the need for standardized manufacturing of these cells. However, many challenges related to diverse isolation and expansion protocols and differences in cell tissue sources exist. As a result, the cell products used in numerous trials vary greatly in characteristics and potency.MethodsThe authors have established a standardized culture platform using xeno- and serum-free commercial media for expansion of MSCs derived from umbilical cord (UC), bone marrow and adipose-derived (AD) and examined their functional characteristics.ResultsMSCs from the tested sources stably expanded in vitro and retained their biomarker expression and normal karyotype at early and later passages and after cryopreservation. MSCs were capable of colony formation and successfully differentiated into osteogenic, adipogenic and chondrogenic lineages. Pilot expansion of UC-MSCs and AD-MSCs to clinical scale revealed that the cells met the required quality standard for therapeutic applications.ConclusionsThe authors’ data suggest that xeno- and serum-free culture conditions are suitable for large-scale expansion and enable comparative study of MSCs of different origins. This is of importance for therapeutic purposes, especially because of the numerous variations in pre-clinical and clinical protocols for MSC-based products.  相似文献   
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In 2010–2011, experimental commercial cultivation of 14 species of hermatypic corals was carried out using the method of donor colony fragmentation. The transplants successfully survived on experimental frame installations. The coral colonies that were recovered from the fragments became attached to the frame installations in a similar way to their attachment on natural substrata. After 1 year, the size of the trans-plants was found to have increased by 275%. The newly formed artificial coral community was colonized by the damselfish Dascyllus reticulates (Pomacentridae); the species is a common coral fish species that lives on natural reefs.  相似文献   
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The cell cycle plays an important role in the development and adaptation of multicellular organisms; specifically, it allows them to optimally adjust their architecture in response to environmental changes. Kip-related proteins (KRPs) are important negative regulators of cyclin-dependent kinases (CDKs), which positively control the cell cycle during plant development. The Arabidopsis genome possesses seven KRP genes with low sequence similarity and distinct expression patterns; however, why Arabidopsis needs seven KRP genes and how these genes function in cell cycle regulation are unknown. Here, we focused on the characterization of KRP3, which was found to have unique functions in the shoot apical meristem (SAM) and leaves. KRP3 protein was localized to the SAM, including the ground meristem and vascular tissues in the ground part of the SAM and cotyledons. In addition, KRP3 protein was stabilized when treated with MG132, an inhibitor of the 26S proteasome, indicating that the protein may be regulated by 26S proteasome-mediated protein degradation. KRP3-overexpressing (KRP3 OE) transgenic plants showed reduced organ size, serrated leaves, and reduced fertility. Interestingly, the KRP3 OE transgenic plants showed a significant reduction in the size of the SAM with alterations in cell arrangement. In addition, compared to the wild type, the KRP3 OE transgenic plants had a higher DNA ploidy level in the SAM and leaves. Taken together, our data suggest that KRP3 plays important regulatory roles in the cell cycle and endoreduplication in the SAM and leaves.  相似文献   
67.
Interstitial cells of Cajal (ICCs) are the pacemakers of the gastrointestinal tract, and transient receptor potential melastatin type 7 (TRPM7) and Ca2+ activated Cl channels (ANO1) are candidate the generators of pacemaker potentials in ICCs. The effects of D-erythro-sphingosine (SPH) and structural analogues of SPH, that is, N,N-dimethyl-Derythro-sphingosine (N,N-DMS), FTY720, and FTY720-P on the pacemaking activities of ICCs were examined using the whole cell patch clamp technique. SPH, N,N-DMS, and FTY720 decreased the amplitudes of pacemaker potentials in ICC clusters, but resting membrane potentials displayed little change. Also, perfusing SPH, N,N-DMS, or FTY720 in the bath reduced both inward and outward TRPM7-like currents in single ICCs, and inhibited ANO1 currents. The another structural analogue of SPH, FTY720-P was ineffective at the pacemaker potentials in ICC clusters and the TRPM7-like currents in single ICCs. Furthermore, FTY720- P had no effect on ANO1. These results suggest that SPH, N,N-DMS, and FTY720 modulate the pacemaker activities of ICCs, and that TRPM7 and ANO1 channels affect intestinal motility.  相似文献   
68.
Kim  Ok-Hee  Kang  Gun-Hyung  Noh  Hyungjoon  Cha  Ji-Young  Lee  Ho-Jae  Yoon  Jeong-Hwan  Mamura  Mizuko  Nam  Jeong-Seok  Lee  Dae Ho  Kim  Young A.  Park  Young Joo  Kim  Hyeonjin  Oh  Byung-Chul 《Molecules and cells》2013,36(5):432-438
Tumor-associated macrophages (TAMs) accumulate in various cancers and promote tumor angiogenesis and metastasis, and thus may be ideal targets for the clinical diagnosis of tumor metastasis with high specificity. However, there are few specific markers to distinguish between TAMs and normal or inflammatory macrophages. Here, we show that TAMs localize in green fluorescent protein-labeled tumors of metastatic lymph nodes (MLNs) from B16F1 melanoma cells but not in necrotic tumor regions, suggesting that TAMs may promote the growth of tumor cells and the progression of tumor metastasis. Furthermore, we isolated pure populations of TAMs from MLNs and characterized their gene expression signatures compared to peritoneal macrophages (PMs), and found that TAMs significantly overexpress immunosuppressive cytokines such as IL-4, IL-10, and TGF-β as well as proangiogenic factors such as VEGF, TIE2, and CD31. Notably, immunological analysis revealed that TIE2+/CD31+ macrophages constitute the predominant population of TAMs that infiltrate MLNs, distinct from tissue or inflammatory macrophages. Importantly, these TIE2+/CD31+ macrophages also heavily infiltrated MLNs from human breast cancer biopsies but not reactive hyperplastic LNs. Thus, TIE2+/CD31+ macrophages may be a unique histopathological biomarker for detecting metastasis in clinical diagnosis, and a novel and promising target for TAM-specific cancer therapy.  相似文献   
69.
Bacillus sp B55, a bacterium naturally associated with Nicotiana attenuata roots, promotes growth and survival of wild-type and, particularly, ethylene (ET)–insensitive 35S-ethylene response1 (etr1) N. attenuata plants, which heterologously express the mutant Arabidopsis thaliana receptor ETR1-1. We found that the volatile organic compound (VOC) blend emitted by B55 promotes seedling growth, which is dominated by the S-containing compound dimethyl disulfide (DMDS). DMDS was depleted from the headspace during cocultivation with seedlings in bipartite Petri dishes, and 35S was assimilated from the bacterial VOC bouquet and incorporated into plant proteins. In wild-type and 35S-etr1 seedlings grown under different sulfate (SO4−2) supply conditions, exposure to synthetic DMDS led to genotype-dependent plant growth promotion effects. For the wild type, only S-starved seedlings benefited from DMDS exposure. By contrast, growth of 35S-etr1 seedlings, which we demonstrate to have an unregulated S metabolism, increased at all SO4−2 supply rates. Exposure to B55 VOCs and DMDS rescued many of the growth phenotypes exhibited by ET-insensitive plants, including the lack of root hairs, poor lateral root growth, and low chlorophyll content. DMDS supplementation significantly reduced the expression of S assimilation genes, as well as Met biosynthesis and recycling. We conclude that DMDS by B55 production is a plant growth promotion mechanism that likely enhances the availability of reduced S, which is particularly beneficial for wild-type plants growing in S-deficient soils and for 35S-etr1 plants due to their impaired S uptake/assimilation/metabolism.  相似文献   
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