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Previously we reported that, lactic acid bacteria (LAB) can induce human dermal fibroblast (HDF) cells to form multipotent cell clusters which are able to transdifferentiate into three germ layer derived cell lineages. Later on, we confirmed that ribosome is responsible for the LAB-induced transdifferentiation and ribosomes from diverse organisms can mimic the LAB effect on HDF cells. In our present study we have shown that, upon incorporation of ribosomes, non-small cell lung cancer cell line A549 and gastric tubular adenocarcinoma cell line H-111-TC are transformed into spheroid like morphology those can be transdifferentiated into adipocytes and osteoblast. Our qPCR analysis has revealed that, during the formation of ribosome induced cancer cell spheroids, the expression of the cancer cell associated markers and cell cycle/proliferation markers were altered at different time point. Through our investigation, here we report a novel and a non-invasive approach for cancer cell reprogramming by incorporating ribosomes.  相似文献   
34.
The shoot apical meristem is the ultimate source of the cells that constitute the entire aboveground portion of the plant body. In Arabidopsis thaliana, meristem maintenance is regulated by the negative feedback loop of WUSCHEL-CLAVATA (WUS-CLV). Although CLV-like genes, such as FLORAL ORGAN NUMBER1 (FON1) and FON2, have been shown to be involved in maintenance of the reproductive meristems in rice (Oryza sativa), current understanding of meristem maintenance remains insufficient. In this article, we demonstrate that the FON2-LIKE CLE PROTEIN1 (FCP1) and FCP2 genes encoding proteins with similar CLE domains are involved in negative regulation of meristem maintenance in the vegetative phase. In addition, we found that WUSCHEL-RELATED HOMEOBOX4 (WOX4) promotes the undifferentiated state of the meristem in rice and that WOX4 function is associated with cytokinin action. Consistent with similarities in the shoot apical meristem phenotypes caused by overexpression of FCP1 and downregulation of WOX4, expression of WOX4 was negatively regulated by FCP1 (FCP2). Thus, FCP1/2 and WOX4 are likely to be involved in maintenance of the vegetative meristem in rice.  相似文献   
35.

A monoclonal antibody (DEM-1) specific for the Dewar photoproduct is used for detection and quantification of photolesions in DNA. To help understand the molecular recognition of damaged DNA by the antibody protein, we have cloned and sequenced the variable region genes of DEM-1. We have also prepared Fab fragments of DEM-1 (DEM1Fab), and synthesized two kinds of 3′-biotinylated oligonucleotides of different lengths containing a central Dewar photoproduct of TpT to analyze the effects of the antigen size on the binding rates by means of surface plasmon resonance (SPR). Results obtained from SPR analyses suggest that DEM1Fab may recognize tetranucleotide unit as the epitope.  相似文献   
36.
Ovarian clear cell adenocarcinoma (CCC) is the second most common subtype of ovarian cancer after high-grade serous adenocarcinomas. CCC tends to develop resistance to the standard platinum-based chemotherapy, and has a poor prognosis when diagnosed in advanced stages. The ANXA4 gene, along with its product, a Ca++-binding annexin A4 (ANXA4) protein, has been identified as the CCC signature gene. We reported two subtypes of ANXA4 with different isoelectric points (IEPs) that are upregulated in CCC cell lines. Although several in vitro investigations have shown ANXA4 to be involved in cancer cell proliferation, chemoresistance, and migration, these studies were generally based on its overexpression in cells other than CCC. To elucidate the function of the ANXA4 in CCC cells, we established CCC cell lines whose ANXA4 expressions are stably knocked down. Two parental cells were used: OVTOKO contains almost exclusively an acidic subtype of ANXA4, and OVISE contains predominantly a basic subtype but also a detectable acidic subtype. ANXA4 knockdown (KO) resulted in significant growth retardation and greater sensitivity to carboplatin in OVTOKO cells. ANXA4-KO caused significant loss of migration and invasion capability in OVISE cells, but this effect was not seen in OVTOKO cells. We failed to find the cause of the different IEPs of ANXA4, but confirmed that the two subtypes are found in clinical CCC samples in ratios that vary by patient. Further investigation to clarify the mechanism that produces the subtypes is needed to clarify the function of ANXA4 in CCC, and might allow stratification and improved treatment strategies for patients with CCC.  相似文献   
37.

Background

The Fukushima Daiichi nuclear disaster caused a global panic by a release of harmful radionuclides. In a disaster setting, misusage of contemporary media sources available today can lead to disseminated incorrect information and panic. The study aims to build a scale which examines associations between media and individual anxieties, and to propose effective media usages for future disaster management.

Methods

The University of Tokyo collaborated with the Fukushima local government to conduct a radiation-health-seminar for a total of 1560 residents, at 12 different locations in Fukushima. A 13 item questionnaire collected once before and after a radiation-seminar was used on factor analysis to develop sub-scales for multiple regression models, to determine relationships between the sub-scales and media type consumed. A paired t–test was used to examine any changes in sub-scale of pre- and post-seminar scores.

Results

Three sub-scales were revealed and were associated with different media types: was with rumors, while concern for the future was positively associated with regional-newspapers and negatively with national-newspapers. Anxiety about social-disruption was associated with radio. The seminar had a significant effect on anxiety reduction for all the three sub-scales.

Conclusion

Different media types were associated with various heightened concerns, and that a radiation seminar was helpful to reduce anxieties in the post-disaster setting. By tailoring post-disaster messages via specific media types, i.e., radio, it may be possible to effectively convey important information, as well as to calm fears about particular elements of post-disaster recovery and to combat rumors.  相似文献   
38.
Plant organ growth is controlled by inter-cell-layer communication, which thus determines the overall size of the organism. The epidermal layer interfaces with the environment and participates in both driving and restricting growth via inter-cell-layer communication. However, it remains unknown whether the epidermis can send signals to internal tissue to limit cell proliferation in determinate growth. Very-long-chain fatty acids (VLCFAs) are synthesized in the epidermis and used in the formation of cuticular wax. Here we found that VLCFA synthesis in the epidermis is essential for proper development of Arabidopsis thaliana. Wild-type plants treated with a VLCFA synthesis inhibitor and pasticcino mutants with defects in VLCFA synthesis exhibited overproliferation of cells in the vasculature or in the rib zone of shoot apices. The decrease of VLCFA content increased the expression of IPT3, a key determinant of cytokinin biosynthesis in the vasculature, and, indeed, elevated cytokinin levels. These phenotypes were suppressed in ipt3;5;7 triple mutants, and also by vasculature-specific expression of cytokinin oxidase, which degrades active forms of cytokinin. Our results imply that VLCFA synthesis in the epidermis is required to suppress cytokinin biosynthesis in the vasculature, thus fine-tuning cell division activity in internal tissue, and therefore that shoot growth is controlled by the interaction between the surface (epidermis) and the axis (vasculature) of the plant body.  相似文献   
39.
Oxygen is a key regulator of both development and homeostasis and a promising candidate to bridge the influence of the environment and the evolution of new traits. To clarify the various ways in which oxygen may modulate embryogenesis, its effects are reviewed at distinct organizational levels. First, the role of pathways that sense dioxygen levels and reactive oxygen species are reviewed. Then, the effects of microenvironmental oxygen on metabolism, stemness, and differentiation throughout embryogenesis are discussed. Last, the interplay between ecology and development are reexamined with a focus on the evolution of tetrapods, including during the emergence of a novel mechanism that shapes amniote limbs—interdigital cell death. Both genetic and environmental components work together during the formation of organisms, highlighting the importance of a multidisciplinary approach for understanding the evolution of new traits.  相似文献   
40.
Specialized microenvironment, or neurogenic niche, in embryonic and postnatal mouse brain plays critical roles during neurogenesis throughout adulthood. The subventricular zone (SVZ) and the dentate gyrus (DG) of hippocampus in the mouse brain are two major neurogenic niches where neurogenesis is directed by numerous regulatory factors. Now, we report Akhirin (AKH), a stem cell maintenance factor in mouse spinal cord, plays a pivotal regulatory role in the SVZ and in the DG. AKH showed specific distribution during development in embryonic and postnatal neurogenic niches. Loss of AKH led to abnormal development of the ventricular zone and the DG along with reduction of cellular proliferation in both regions. In AKH knockout mice (AKH−/−), quiescent neural stem cells (NSCs) increased, while proliferative NSCs or neural progenitor cells decreased at both neurogenic niches. In vitro NSC culture assay showed increased number of neurospheres and reduced neurogenesis in AKH−/−. These results indicate that AKH, at the neurogenic niche, exerts dynamic regulatory role on NSC self-renewal, proliferation and differentiation during SVZ and hippocampal neurogenesis.  相似文献   
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