• 제목/요약/키워드: environmental activity factor

검색결과 393건 처리시간 0.022초

Knockdown of microtubule actin crosslinking factor 1 inhibits cell proliferation in MC3T3-E1 osteoblastic cells

  • Hu, Lifang;Su, Peihong;Li, Runzhi;Yan, Kun;Chen, Zhihao;Shang, Peng;Qian, Airong
    • BMB Reports
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    • 제48권10호
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    • pp.583-588
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    • 2015
  • Microtubule actin crosslinking factor 1 (MACF1), a widely expressed cytoskeletal linker, plays important roles in various cells by regulating cytoskeleton dynamics. However, its role in osteoblastic cells is not well understood. Based on our previous findings that the association of MACF1 with F-actin and microtubules in osteoblast-like cells was altered under magnetic force conditions, here, by adopting a stable MACF1-knockdown MC3T3-E1 osteoblastic cell line, we found that MACF1 knockdown induced large cells with a binuclear/multinuclear structure. Further, immunofluorescence staining showed disorganization of F-actin and microtubules in MACF1-knockdown cells. Cell counting revealed significant decrease of cell proliferation and cell cycle analysis showed an S phase cell cycle arrest in MACF1-knockdown cells. Moreover and interestingly, MACF1 knockdown showed a potential effect on cellular MTT reduction activity and mitochondrial content, suggesting an impact on cellular metabolic activity. These results together indicate an important role of MACF1 in regulating osteoblastic cell morphology and function.

낙동강 하구의 조석변화에 따른 Heterotrophic Activity의 계절적 변화와 염분의 영향 (Seasonal Variation of Heterotrophic Activity in the Estuary of Naktong River over Half Tidal Cycle and Salinity Effect)

  • 안태영;박중찬;하영칠
    • 미생물학회지
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    • 제29권5호
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    • pp.339-343
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    • 1991
  • Heterotrophic activity, total bacteria and salinity were determined seasonally in the estuary of Naktong River over half tidal cycle. Heterotrophic activity was determined by the uptake of [U- $^{14}$ C]glucose. Heterotrophic activity fluctuated with the tides and was decreased as salinity increased. Teh great activity occurred near low ebb tide at all seasons except summer. The main environmental factor affecting hetreotrophic activity was the salinity rather than water temperature in the estuary of Naktong River. In order to estimate the effect of salt, salt was added to estuarine water. Vmax for glucose of salt-added water was 17% and 77% of original estuarine water at station 1 and 2 respectively and slight increase was observed at station 3. Respiration rate and Kt+Sn for glucose of salt-added sample increased at all 3 stations. The increase of the Kt value implies the reduced affinity of bacterial population for glucose. The effects of salinity on the heterotrophic activity were more extensive in the upper region of estuary than at the mouth.

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Aloe vera의 연 유도성 신경계 독성 저감 기전에 관한 연구 (A study on the mechanism for reduction of lead-induced toxicity in nervous system by aloe vera)

  • 정명규;곽영규
    • 한국환경보건학회지
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    • 제22권3호
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    • pp.8-16
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    • 1996
  • Effects of water extract of aloe vera on lead-induced neurotoxicity were investigated in sciatic nerve isolated from rat. The mechanism on toxicity reduction by measuring activities of axonal enzymes, metabolism of myo-inositol in nerve, lead concentration in several organs and so on were further examimed. In the lead-treated rats, the transport rate of axonal enzyme, such as acetyl cholinesterase and choline acetyltransferase, was reduced by from 50% to 30% respectively. Reduction in myo-inositol concentration and $Na^+/K^+$ ATPase activity were also observed in sciatic nerve from lead-treated rat. However, the aloe extract administration significantly eliminated the impairment and maintained myo-inositol concentration to about 85% of normal level. Also aloe extract promoted the excretion rate of lead which is accumulated in blood, sciatic nerve and kidney. These results suggest that lead-induced neurotoxicity was significantly reduced by administration of aloe extract and the mechanism might be partly increase in kidney excretion rate of lead and parity normalization of $Na^+/K^+$ ATPase activity which is critical factor in order to keep nerve maintaining normal myo-inositol level.

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부유형 챔버를 이용한 하수처리장에서의 암모니아 배출 특성 연구 (Development of NH3 Emission Factors using a Dynamic Flux Chamber in a Sewage Treatment Plant)

  • 전의찬;사재환;박종호
    • 환경영향평가
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    • 제14권5호
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    • pp.263-273
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    • 2005
  • In this study, the major emission procedures and emission characteristics were identified at the site of sewage treatment plant which is one of the major sources of ammonia. At the same time the emission factors and emission rates were estimated. In order to calculate the emission flux, we used a Dynamic Flux Chamber(DFC), which is found to be a proper sampling devise for area sources such as sewage treatment plant. It was found that the most stable sampling condition was when the stirrer's speed of DFC was 120RPM, and it would be the best time to take a sample 60 minutes later after setting the chamber. The relatively higher flux was shown in Autumn compared to summer and winter. Annual ammonia emission rates procedures were calculated as $906.32{\mu}g/activity-ton$, $1,114.72{\mu}g/activity-ton$ and $437.53{\mu}g/activity-ton$ each at the primary settling basin, aeration basin and the final settling basin, respectively. The ammonia emission rate the highest at in the aeration basin according to this test. This results was due to that the surface of aeration basin or the final settling basin is relatively wider than the primary settling basin.

걷기활동 증진을 위한 보행환경 평가지표의 개발 (Developing the Evaluation Indicator of Pedestrian Environment for Promoting Walking Activity)

  • 박경훈;박종완;정성관;유주한
    • 한국환경과학회지
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    • 제16권11호
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    • pp.1231-1238
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    • 2007
  • The promotion of walking and bicycling is recently a hot topic in the urban planning and design field. Many planners have already examined the many components of the land use-transportation connection and built environment-physical activity link. A rapidly growing area of urban form research is to measure the level of walk-ability in urban environments. With this background, this research conducted a preliminary study to develop the evaluation indicators of pedestrian environments. Based on the literature reviews on walking or pedestrian environments, we proposed the seventeen indicators related with pedestrian facilities, road attributes and walking environment. We also performed a questionary survey to evaluate the satisfaction of their neighborhood pedestrian environments for 302 randomly selected adults living in the City of Changwon, Gyeongsangnam-do. Finally, this research provided the valid model to evaluate the effects of physical environmental factors on the walking satisfaction using factor analysis and multiple regression analysis.

Evaluation of Impact of Tobacco Smoke on Indoor Air Quality

  • Lee, Hak-Sung;Robert A. O'brien
    • Journal of Korean Society for Atmospheric Environment
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    • 제9권E호
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    • pp.358-363
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    • 1993
  • Total particulate mater (TPM), $NO_2$ and $NH_3$ were measured simultaneously in the smoking and non-smoking locations during an eleven month period from March 1986 to January 1987 at three sites in Chicago : Illinois Institute of Technology Cafeteria, Rush-Presbyterian St. Lukes Medical Center Cafeteria and a downtown office building. From this study, the mean concentrations of $NO_2$ and $NH_3$ were not significantly different between the smoking and non-smoking locations at any sampling site ; however, there was a statistical difference for TPM between the smoking and non-smoking locations. Activity factor was useful for describing the contribution from indoor source. The linear regression analysis was reasonable method for discriminating the individual contribution of source to determine the emission factor. The TPM emission factor determined from this technique was in good agreement with value from the literature.

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Reevaluation of bactericidal, cytotoxic, and macrophage-stimulating activities of commercially available Fucus vesiculosus fucoidan

  • Nishiguchi, Tomoki;Jiang, Zedong;Ueno, Mikinori;Takeshita, Satoshi;Cho, Kichul;Roh, Seong Woon;Kang, Kyong-Hwa;Yamaguchi, Kenichi;Kim, Daekyung;Oda, Tatsuya
    • ALGAE
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    • 제29권3호
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    • pp.237-247
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    • 2014
  • Polysaccharides prepared from marine algae sometimes contain contaminants such as polyphenols and endotoxins that may mislead their bona fide biological activities. In this study, we examined bioactive contaminants in commercially available fucoindan from Fucus vesiculosus, along with ascophyllan and fucoidan from Ascophyllum nodosum. F. vesiculosus fucoidan inhibited the growth of Vibrio alginolyticus in a concentration-dependent manner ($0-1,000{\mu}g\;mL^{-1}$). However, the antibacterial activity of the fucoidan significantly reduced after methanol-extraction, and the methanol-extract showed a potent antibacterial activity. The extract also showed cytotoxicity to RAW264.7 and U937 cells, and induced apoptotic nuclear morphological changes in U937 cells. These results suggest that the antibacterial activity of the fucoidan is partly due to the methanol-extractable contaminants that can also contribute to the cytotoxicity on RAW264.7 and U937 cells. On the other hand, the activities to induce secretion of nitric oxide and tumor necrosis factor-${\alpha}$ from RAW264.7 cells were observed in the fucoidan even after methanol extraction, and the extract had no such activities. Our observations suggest that commercially available fucoidan should be purified prior to biochemical use.

병원근로자의 근골격계질환 증상 특성 및 관리방안 (Musculoskeletal Disorder Symptom Features and Control Strategies in Hospital Workers)

  • 박정근;김대성;서경범
    • 대한인간공학회지
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    • 제27권3호
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    • pp.81-92
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    • 2008
  • Musculoskeletal disorder (MSD) problems have been increasingly reported in hospital sector but the problems were not addressed with respect to holistic aspects of the target population in Korea. Often, it is required to understand how MSD symptoms are associated with factors such as personal, work environmental and psychosocial stressors. To examine features of association between sets of MSD symptoms and the factors, a questionnaire survey was conducted in a university hospital. A 140-item questionnaire was developed and used for collecting information including factors (e.g., job/occupation, task/activity, job stress) and MSD symptoms. A total of 1,091 workers (male 23.7% and female 76.3%) were finally determined for data analyses. Prevalence rate for the whole body was 72% and, among body parts, the highest was 48.7% for the shoulder, followed by 34.6%(the low back), 32.7%(the leg/foot), 27.9%(the neck), 26.7%(the wrist) and 12%(the elbow). The symptoms were significantly different by job/occupational variable in each of all body parts except the neck. The symptoms were very significantly different by task/activity variables in each of all body parts while those symptoms were significantly different by psychosocial variables, depending on body part and gender. In the logistic regression analyses performed for MSD symptoms by body part and each of 3 factors, odds ratio values varied, ranging from 0.7 to 3.3. The controls for reducing the symptoms were discussed on the basis of the findings. The results show that the MSD symptoms can remarkably vary by the factors and, in particular, can be highly differential for the task/activity factor. This study suggests that MSD symptom features be examined by using various factors and then a higher differential factor be primarily utilized for controling MSD symptoms in general industry including hospital settings.

A Review on the Emission Sources of Ammonia and the Factors Affecting Its Loss

  • Das, Piw;Sa, Jae-Hwan;Kim, D.S.;Kim, K.H.;Jeon, E.C.
    • Journal of Korean Society for Atmospheric Environment
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    • 제23권E2호
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    • pp.47-56
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    • 2007
  • Among all the nitrogen species present in the atmosphere, ammonia forms a considerable portion along with the nitrogen oxides. The major sources of atmospheric ammonia are animal feedlot operations including emission from excreta of domestic animals and agricultural activities, followed by emission from synthetic fertilizers, biomass burning and to some lesser extent, fossil fuel combustion. Ammonia emission factor, expressed as the weight of ammonia per unit weight, volume, or duration of the activity emitting it, is generally used in developing emission estimates for emission inventories. The factors determining ammonia loss from soil or from manures are the temperature, pH, humidity, precipitation and the velocity of wind above it.

PIF4 Integrates Multiple Environmental and Hormonal Signals for Plant Growth Regulation in Arabidopsis

  • Choi, Hyunmo;Oh, Eunkyoo
    • Molecules and Cells
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    • 제39권8호
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    • pp.587-593
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    • 2016
  • As sessile organisms, plants must be able to adapt to the environment. Plants respond to the environment by adjusting their growth and development, which is mediated by sophisticated signaling networks that integrate multiple environmental and endogenous signals. Recently, increasing evidence has shown that a bHLH transcription factor PIF4 plays a major role in the multiple signal integration for plant growth regulation. PIF4 is a positive regulator in cell elongation and its activity is regulated by various environmental signals, including light and temperature, and hormonal signals, including auxin, gibberellic acid and brassinosteroid, both transcriptionally and post-translationally. Moreover, recent studies have shown that the circadian clock and metabolic status regulate endogenous PIF4 level. The PIF4 transcription factor cooperatively regulates the target genes involved in cell elongation with hormone-regulated transcription factors. Therefore, PIF4 is a key integrator of multiple signaling pathways, which optimizes growth in the environment. This review will discuss our current understanding of the PIF4-mediated signaling networks that control plant growth.