1,721,696 research outputs found
The Effect of Capsaicin on Salivary Gland Dysfunction
No full textCapsaicin (trans-8-methyl-N-vanilyl-6-nonenamide) is a unique alkaloid isolated from hot chili peppers of the capsicum family. Capsaicin is an agonist of transient receptor potential vanilloid subtype 1 (TRPV1), which is expressed in nociceptive sensory neurons and a range of secretory epithelia, including salivary glands. Capsaicin has analgesic and anti-inflammatory properties in sensory neurons. Recently, increasing evidence has indicated that capsaicin also affects saliva secretion and inflammation in salivary glands. Applying capsaicin increases salivary secretion in human and animal models. Capsaicin appears to increase salivation mainly by modulating the paracellular pathway in salivary glands. Capsaicin activates TRPV1, which modulates the permeability of tight junctions (TJ) by regulating the expression and function of putative intercellular adhesion molecules in an ERK (extracelluar signal-regulated kinase) -dependent manner. Capsaicin also improved dysfunction in transplanted salivary glands. Aside from the secretory effects of capsaicin, it has anti-inflammatory effects in salivary glands. The anti-inflammatory effect of capsaicin is, however, not mediated by TRPV1, but by inhibition of the NF-κB pathway. In conclusion, capsaicin might be a potential drug for alleviating dry mouth symptoms and inflammation of salivary glands
MTA promotes chemotaxis and chemokinesis of immune cells through distinct calcium-sensing receptor signaling pathways
No full textMineral trioxide aggregate (MTA) has been introduced as a choice material for regenerative dentistry. To date, the diverse biological activities of MTA, including its anti-inflammatory effects, have been extensively discussed. However, there is limited insight into the link between MTA and immune cell migration. In this study, we report the role of MTA in enhancing both chemotactic and chemokinetic immune cell migration through distinct signaling pathways. By using versatile live imaging techniques, we demonstrated that MTA-mediated CaSR activation induced diverse downstream pathways to govern cell migratory capacity. In this context, Cdc42 generates cytoskeleton-driven cellular protrusions to steer directional cell migration (chemotaxis) whereas Cg(2+)-calmodulin dependent myosin light chain kinase induces cell contractility that plays an important role in speeding up the average migration speed (chemokinesis). Our findings illuminate an unrecognized role for MTA and the related CaSR signaling network in immune cell migration, providing evidence that can drive development of novel approaches to immunological therapy. (C) 2017 Elsevier Ltd. All rights reserved.OAIID:RECH_ACHV_DSTSH_NO:T201720205RECH_ACHV_FG:RR00200001ADJUST_YN:EMP_ID:A001677CITE_RATE:8.806DEPT_NM:치의과학과EMAIL:[email protected]_YN:YN
유방암 세포를 조작하고 정량화하기 위한 고주파 초음파 시스템 개발
No full textRecently, many high frequency ultrasound microbeam techniques such as acoustic tweezers, acoustic mi-croscopy, and a single cell stimulator have been developed for various biomedical applications. In this the-sis, I developed a high frequency ultrasound microbeam system with a 30MHz single element lithium nio-bate (LiNbO3) ultrasound transducer for cancer cell manipulation and characterization. A single-element LiNbO3 ultrasound transducer with a center frequency of 30 MHz and an f-number of ~ 0.7 was employed to form highly-focused ultrasound microbeams at focus for manipulation of a cell. Sine-bursts from a func-tion generator were input to the transducer after amplification in a RF power amplifier of a home-built puls-er-receiver for generation of the high frequency ultrasound microbeams. The ultrasound transducer was integrated to x-, y-, and z- linear motorized stages and then attached to an inverted fluorescence microscope to manipulate and characterize a cancer cell. The motorized stages were here controlled by a program de-veloped for precise beam focusing to a target cell. Also, an electron multiplying charge coupled device was implemented to the microscope in order to perform live-cell fluorescence imaging for monitoring and char-acterizing of a target cell. To evaluate the performance of the high frequency ultrasound microbeam system I developed, the system was applied to trap a 10 μm polystyrene microbead in a highly-focused microbeam and the performance of acoustic trapping of the microbead in transparent and turbid media has been then compared. The results demonstrated that a 10 μm polystyrene microbead could be successfully trapped in the media by using the system. Interestingly, it was found that its trapping performance was degraded in the turbid media compared to the transparent media. Furthermore, the system was employed as acoustic twee-zers to manipulate and characterize a cancer cell for development of more useful biomedical applications. In particular, I investigated whether the degree of invasiveness of breast cancer cells with different pheno-types in suspension could be realized by quantification of morphological and calcium responses of cancer cells to acoustic trapping. The results showed that the highly-invasive breast cancer cell (MDA-MB-231) was likely to exhibit strong calcium responses at lower input voltages than the weakly-invasive breast cancer cell (MCF-7) during acoustic trapping as well as the highly-invasive breast cancer cell was largely deformed than the weakly-invasive breast cancer cell due to acoustic trapping at a certain input voltage. Altogether, these results suggested that breast cancer cells with different phenotypes in suspension might be discriminated by quantification of morphological and molecular responses of the cells to acoustic trapping using the high frequency ultrasound microbeam system I developed, thus demonstrating it potentials as a promising bio-physical tool for cancer cell manipulation and characterization. ⓒ 2016 DGISTI. INTRODUCTION 1--
II. METHODS 5--
2.1 System Architecture 5--
i. Ultrasound Transducer 6--
ii. Signal generator 7--
iii. Power Amplifier 8--
iv. 3-axis motorized stage 9--
2.2 Cell Preparation 12--
i. Cell Selection 12--
2.3 Area deformation quantification method 13--
III. RESULT 15--
3.1 Evaluation of the high frequency ultrasound microbeam system 15--
i. Acoustic trapping performance in clear media 15--
ii. Acoustic trapping performance in turbid media 16--
3.2 Deformation of cancer cells by acoustic trapping 17--
3.3 Calcium elevation in cancer cells by acoustic trapping 18--
3.4 Cell viability test 19--
IV. DISCUSSION 20--
V. CONCLUSION 23--
REFERENCE 25--최근 고주파 초음파 마이크로빔을 이용하여 다양한 의료응용을 목적으로 초음파집게, 초음파 현미경, 단일 세포 자극 시스템 등이 다수 개발되고 있다. 본 논문에서 30MHz 단일 초음파 변환자를 이용하여 암세포를 조작하고 그 분자 특성을 분석 하기위한 고주파 초음파 마이크로빔 시스템을 개발함. 이 시스템에서 사용된 단일 소자 LiNbO3 초음파 변환자의 센터 주파수는 30MHz, f-number 값은 0.7로 세포를 조작하기 위해 초음파를 강력하게 집속할 수 있도록 설계되었다. 초음파를 발생시키기 위해 함수 발생기로부터 펄스화 된 사인파를 발생시키고 이를 10MHz 에서 60MHz 사이로 동작하는RF 증폭기를 통해 증폭 후 초음파 변환자에 인가함. 초음파 변환자는 3축 모터제어 스테이지와 함께 IX73 도립 현광 현미경에 부착함. 모터제어 스테이지는 정밀하게 초음파 빔 초점을 조절하기 위한 프로그램으로 제어됨. 또한, 형광 현미경 기술을 사용하여 세포를 관찰하고 정량화 할 수 있는 시스템을 구성함. 구성된 초음파 집게의 성능을 평가하기 위해 마이크로비드를 각기 투명한 용액과 혼탁한 용액 안에서 포획하고 그 성능을 평가하고 비교함. 실험 결과 10um 마이크로비드가 그 용액 안에서 성공적으로 초음파집게에 잡히는 것을 확인하였고, 혼탁한 미디어내에서 그 초음파 집게 성능이 약화 되는 현상을 관찰함. 더불어, 이 초음파 집게 시스템을 의료용으로 유용하게 응용될 수 있도록 암세포를 조작하고 정량화하는데 적용하였음. 높은 침습성을 가진세포와 낮은 짐습성을 가진 유방암 세포들을 초음파 집게를 이용해 포획 시 그 세포들의 형태학적, 분자적 즉 칼슘 반응을 정량화해서 분별 될 수 있는지 조사함. 여기서 높은 칩슴성을 가진 세포 (MDA-MB-231)는 낮은 침습성을 가진 세포 (MCF7)과 달리 낮은 전압에서 강한 칼슘 반응을 나타내는 경향을 보임. 더욱이, 높은 침습성을 가진 유방암 세포는 낮은 침습성을 가진 유방암 세포에 비해 초음파 집게의 음압 하에서 더 크게 형태가 변화하는 모습을 보임. 그러므로, 이러한 결과들은 다른 표현형을 가진 유방암 세포들이 그들의 초음파빔의 포획에 의한 형태학적, 분자적 반응을 정량화함으로써 그 특성들을 파악할 수 있다는 것을 나타냄. 이러한 결과들은 이 시스템의 암세포 조작 및 정량적 분석이 가능한 생물리학 장비로써의 그 잠재성을 나타냄. ⓒ 2016 DGISTMasterdCollectio
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
A mechanogenetic role for the actomyosin complex in branching morphogenesis of epithelial organs
No full textThe actomyosin complex plays crucial roles in various life processes by balancing the forces generated by cellular components. In addition to its physical function, the actomyosin complex participates in mechanotransduction. However, the exact role of actomyosin contractility in force transmission and the related transcriptional changes during morphogenesis are not fully understood. Here, we report a mechanogenetic role of the actomyosin complex in branching morphogenesis using an organotypic culture system of mouse embryonic submandibular glands. We dissected the physical factors arranged by characteristic actin structures in developing epithelial buds and identified the spatial distribution of forces that is essential for buckling mechanism to promote the branching process. Moreover, the crucial genes required for the distribution of epithelial progenitor cells were regulated by YAP and TAZ through a mechanotransduction process in epithelial organs. These findings are important for our understanding of the physical processes involved in the development of epithelial organs and provide a theoretical background for developing new approaches for organ regeneration.Y
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Targeting Actomyosin Contractility Suppresses Malignant Phenotypes of Acute Myeloid Leukemia Cells
No full textActomyosin-mediated contractility is required for the majority of force-driven cellular events such as cell division, adhesion, and migration. Under pathological conditions, the role of actomyosin contractility in malignant phenotypes of various solid tumors has been extensively discussed, but the pathophysiological relevance in hematopoietic malignancies has yet to be elucidated. In this study, we found enhanced actomyosin contractility in diverse acute myeloid leukemia (AML) cell lines represented by highly expressed non-muscle myosin heavy chain A (NMIIA) and increased phosphorylation of the myosin regulatory light chain. Genetic and pharmacological inhibition of actomyosin contractility induced multivalent malignancy- suppressive effects in AML cells. In this context, perturbed actomyosin contractility enhances AML cell apoptosis through cytokinesis failure and aryl hydrocarbon receptor activation. Moreover, leukemic oncogenes were downregulated by the YAP/TAZ-mediated mechanotransduction pathway. Our results provide a theoretical background for targeting actomyosin contractility to suppress the malignancy of AML cells
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
G protein-coupled calcium-sensing receptor is a crucial mediator of MTA-induced biological activities
No full textMineral trioxide aggregate (MTA) is a calcium silicate-based bioactive material that has been extensively used in dentistry. MTA has been highlighted in its diverse biological functions and excellent clinical outcomes. However, limited insight into the intracellular signaling pathways has been provided to explain the biological activities of MTA. Here, we firstly elucidate that the extracellular calcium-sensing receptor (CaSR) is a major signaling mediator of MTA-induced biological reactions through versatile live imaging techniques of human dental pulp cells (hDPCs). We found that MTA activates diverse CaSR downstream pathways; notably, CaSR activation essentially requires dual modulation of extracellular Ca2+ and pH via MTA. Among the CaSR downstream pathways, Ca2+ mobilization from intracellular stores by the phospholipase C pathway plays an important role in osteogenic differentiation of hDPCs by regulating transcriptional activity. Our findings shed light on the signal transduction mechanism of MTA, thus providing a crucial molecular basis for the use of MTA in regenerative dental therapy. (C) 2017 Elsevier Ltd. All rights reserved.OAIID:RECH_ACHV_DSTSH_NO:T201719750RECH_ACHV_FG:RR00200001ADJUST_YN:EMP_ID:A001677CITE_RATE:8.806DEPT_NM:치의과학과EMAIL:[email protected]_YN:YN
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