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Effects of Vitamin E on the Metallothionein Synthesis in Streptozotocin-induced Diabetic Rats (Streptozotocin유발 당뇨쥐에 있어서 Metallothionein 합성에 미치는 비타민 E의 영향)

  • 이순재;최원경
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.24 no.2
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    • pp.183-194
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    • 1995
  • The purpose of this study was to investigate the effect of vitamin E on the synthesis of the metallothionein in the liver of streptozotocin (STZ)-induced diabetic rats. Sprague-Dawley male rats($220{\pm}10mg$) were randomly assigned to one control and three STZ-diabetic groups. Diabetic groups were classified to STZ-0E(vitamine E free diet), STZ-40E(40mg vitamin E/kg of diet) and STZ-400E(400mg vitamin E/kg of diet) according to the level of vitamin E supplementation. Blood glucose levels of STZ-diabetic rats were three times higher than that of control. The contents of vitamin E in liver were lower signifciantly STZ-0E, STZ-40E groups by 50%, 36% compared with that of control. Lipid peroxide values(LPO) in liver were higher 5.6 and 2.5 times in STZ-0E and STZ-40E groups than that of control. Plasma cortisol levels were higher STZ-0E and STZ-40E groups compared with those of control, but cortisol levels were lower significantly in STZ-400E group compared with those of the STZ-0E and the STZ-40E groups. The plasma insulin levels were lower in all three STZ-diabetic group compared with that of control, but were not affected by the level of dietary vitamin E. The metallothionein (MT) contents in liver, kidney and small intestine were five times higher in STZ-0E, STZ-40E and STZ-400E compared with that of control, but STZ-400E group was lower in the MT contents in tissues compared with that of STZ-40E group. Zn-MT peak in STZ-diabetic rats liver increased than that of control by Sephadex G-75, and Zn-MT peak divided into MTI and MTII peaks by DEAE Sephadex A-25 column chromatography. The present results indicate that STZ-induced diabetic rats are more sensitive to oxidative stress, leading to the acceleration of lipid peroxidation process, which can be more promoted low level of dietary vitamin E. And the result may that increase synthesis of MT induced in the liver of diabetic rats increased so it can be sure that the diabetes is one of the MT induce factor by free radical generation. And high vitamin E supplementation reduced total MT contents of liver, kidney and small intestine and the peak of purified Zn-MT. Through the results of these experiments, we can conclude that MT might be the free radical scavenger.

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Relationship between Graft Appearance on Follow-up MRI and Knee Stability after Double Bundle ACL Reconstruction (이중 다발 전방십자 재건술 후 이식건의 자기공명영상 추시와 슬관절 안정성과의 관계)

  • Sim, Jae Ang;Kwak, Ji Hoon;Lee, Yong Seuk;Kim, Kwang Hui;Nam, Shin Woo;Jun, Sung Soo;Lee, Beom Koo
    • Journal of the Korean Arthroscopy Society
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    • v.16 no.2
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    • pp.128-133
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    • 2012
  • Purpose: This study examined the relationship between graft appearance on follow-up magnetic resonance imaging (MRI) and knee stability after double bundle anterior cruciate ligament (ACL) reconstruction. Materials and Methods: For each patient, 1.5 tesla MRI's were obtained. The signal intensity of grafts was divided into 3 grades by Sononda's classification. The course of grafts was divided into two patterns: straight and curved. We assessed Lachman test, KT 2000 arthrometer and anterior drawer stress radiograph using Telos$^{(R)}$ in $30^{\circ}$ knee flexion for anterior stability and evaluated pivot shift test for rotatory stability. The correlation between graft appearance on MRI and the results of knee stability tests was evaluated. Results: The anteromedial (AM) graft was evaluated as being grade 1 in 66.7%, grade 2 in 26.7%, and grade 3 in 6.7% of the cases and the posterolateal (PL) graft was assessed as being grade 1 in 63.3%, grade 2 in 33.3%, and grade 3 in 3.3% of the cases according to the signal intensity. The AM graft was evaluated as being straight in 83.3% and curved in 16.7% of the cases, and the PL graft was assessed as being straight in 86.7% and curved in 13.3% of the cases according to the course. The course of AM graft was correlated with the results of anterior stability tests and the course of PL graft was correlated with the result of rotatory stability test. However, the signal intensity of grafts was not correlated with the results of anterior stability and rotatory stability tests. Conclusion: The course of AM is correlated with anterior stability and the course of PL is correlated with rotatory stability on follow-up MRI after double bundle ACL reconstruction.

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Effect of Release of the Superficial Medial Collateral Ligament in Repair of the Posterior Medial Meniscus Root Tear (내측 반월상 연골 후각 부착부 봉합술 시 표층 내측측부인대 유리술의 효과)

  • Yang, Byung Se;Lee, Dhong Won;Nam, Sang Wook;Ha, Jeong Ku;Kim, Jin Goo
    • Journal of the Korean Arthroscopy Society
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    • v.16 no.2
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    • pp.114-120
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    • 2012
  • Purpose: The purpose of the study was to evaluate the usefulness and the stability of the superficial medial collateral ligament (MCL) release in posterior medial meniscus root repair. Materials and Methods: We compared 20 patients who underwent posterior medial meniscus root repair with superficial MCL preserved (PM) and 32 patients who underwent posterior medial meniscus root repair combined with superficial MCL release (RM) from April 2006 to September 2010. We excluded the patients combined with other surgery. To evaluate the postoperative valgus instability in RM group, we examined direct tenderness on MCL insertion, the subjective feeling of instability and valgus stress test at 3 months and 1 year follow-up. We compared the tourniquet time between PM group and RM group, and the clinical results were assessed by Lysholm score and International Knee Documentation Committee (IKDC) for the usefulness. Results: All patients had no clinically significant complication related to the superficial MCL release. Three months and 1 year follow-up, there were no positive tenderness test, no subjective symptoms and no significant increase of valgus instability although 5 patients examined grade I valgus instability. The mean tourniquet time was $41.3{\pm}12.7$ minutes in RM group and $53.5{\pm}13.6$ minutes in PM group. There was a significant difference in the tourniquet time between the two groups (P<0.05). Average Lysholm score was $56.8{\pm}5.5$ (range, 44-70) preoperatively and $85.1{\pm}5.8$ (range, 77-94) postoperatively in PM group, and was $56.2{\pm}5.4$ (range, 45-67) preoperatively and $87.4{\pm}3.9$ (range, 82-95) postoperatively in RM group (P<0.001). No significant difference of Lysholm score was found in both groups (P<0.05). Average IKDC scores was $42.6{\pm}3.9$ (range, 30-53) preoperatively and $77.2{\pm}6.3$ (range, 68-92) postoperatively in PM group, and was $42.7{\pm}5.7$ (range, 30-53) preoperatively and $89.6{\pm}2.9$ (range, 84-95) postoperatively in RM group (P<0.05). There was also no significant difference of IKDC score in both groups (P<0.05). Conclusion: The superficial MCL release in posterior medial meniscus root repair is useful to gain a wide surgical field and reduces the tourniquet time and does not lead to postoperative valgus instability. It can be considered clinically useful and safe procedure in medial meniscus posterior root repair.

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Improvement of Proliferation Capacity of Non-adapted CHO Cells Subcultured Using Serum Free Media in Long-term Culture (무혈청 배지에서 계대배양한 비적응 CHO(Chinese Hamster Ovary) 세포의 증식력 개선에 관한 연구)

  • Lee, Seung-Sun;Lee, Jin-Sung;Byun, Soon-Hyu;Park, Hong-Woo;Choe, Tae-Boo
    • KSBB Journal
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    • v.21 no.4
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    • pp.248-254
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    • 2006
  • Animal cell culture industry has a large market and an exponential growth rate among biological industry field. Chines hamster ovary(CHO) cells are the most widely used cell lines for recombinant protein production. They can avoid infection from polio, herpes, hepatitis B, HIV, measles, adenovirus and etc. Moreover it is easy to transfection recombinant genes and possible to suspension culture. Serum free media is one of the most important factor of protein production. Because serum has problems. Serum is not defined the contents until now, it has a number of proteins, lipids, carbohydrates and unknown molecules that cause of risk involve in infection and high cost of product purification. CHO cell line cultured using serum free media were the basis of a very successful method to produce(glyco-)protein in mammalian cells, which are then used as pharmaceutical products. Also, the low protein content of the developed medium facilitates downstream processing and product purification. But non-adapted CHO cells have a limit of proliferation cultured using serum free media and it takes very long time to adapt non-adapted cells to serum free media. There are a number of causes of a limit of proliferation using serum free media. Absence of growth factors and growth stimulating molecules is a major factor of the reasons. It makes growth signals and moves cell cycle. And increase of cellular stress is another reason. It induces increase of intraceullar ROS concentration. The purpose of this study is about improvement of proliferation capacity of non-adapted CHO cells cultured using serum free media without adaptation process.

Growth characteristics and distribution pattern of a brackish water clam, Corbicula japonica along an estuarine salinity gradient in Seomjin River (섬진강 하구역에서 염분구배에 따른 일본재첩의 분포와 성장특성)

  • Baek, Seung Ho;Seo, JIn-Young;Choi, Jin-Woo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.10
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    • pp.6852-6859
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    • 2015
  • The purpose of this study was to determine the growth characteristics and distribution pattern of a brackish water clam Corbicula japonica in Seomjin River. Field samples were taken from 14 stations with salinity gradients during spring. Salinity at the bottom layer ranged from 1.0 psu to 32.9 psu, with low salinities in the upper area of the river. In particular, salinity at St.11 was decreased drastically to be ca. 15.0 psu, indicating an intermediate salinity zone. The distribution pattern of C. japonica was related to the salinity gradient, with the highest densities of $2,102ind.m^{-2}$ at Station 13, followed by $1,507ind.m^{-2}$ at Station 11. Here, we focused on the growth characteristics of collected C. japonica collected at two stations with different salinity values. The relationship between shell length and total weight was highly correlated ($R^2=0.91$, P<0.001) at Station 13 compared to that at Station 11 ($R^2=0.72$, P<0.001). On the other hands, the degree of correlation between shell length and shell height (SH) or shell width (SW) at Station 11 (SH: $R^2=0.91$, P<0.001; SW: $R^2=0.69$, P<0.001) was higher than that at Station 13 (SH: $R^2=0.64$, P<0.001; SW: $R^2=0.48$, P<0.001). In addition, fatness index of C. japonica at Station 13 was significantly (P < 0.001) higher than that at St. 11 (t-test value=-22.8, p<0.001). This implies that C. japonica at Station 13 might have enhanced their somatic growth, whereas C. japonica at Station 11 might have this kind of defense mechanism their internal organization against the salinity stress. Ecologically, this kind of defense mechanism of C. japonica against salinity flucuation may play an important role in their survival strategy.

The Secondary School Education of Geography and the System of Teacher Training in Belgium - Focused on the Case of Francophone Community - (벨지움의 중등학교 지리교육 내용과 교사양성제도 - 프랑코폰 공동체를 사례로 -)

  • Kwak, Chul-Hong
    • Journal of the Korean association of regional geographers
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    • v.6 no.3
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    • pp.101-115
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    • 2000
  • This study aims to make a research on the secondary school education of geography and the system of teacher training in Belgium, focused on the case of Francophone Community. What has been made clear by this research can be summed up as follows. The first two years of the secondary school offer two hours of 'environment education', per week, which can be categorized into the learning of living geography, in that at this stage students learn how to observe the geographic phenomena in their daily life and pigeonhole them. The two years of the second stage of the secondary school offer one hour of 'world geography' which actually is focused on the district of Europe and Russia. The two years of the third stage of the secondary school offer an advanced course of geography which aims to teach systematically the physical geography and the human geography. A remarkable change in geographic education in Belgium is that in the wake of the Revision Act of the secondary school education, textbooks were replaced by other teaching manuals adapted to the regional condition by the teachers. This may result in a wide gap of achievements in geography according to the conditions of educational establishments. Another notable change is that the stress of geographic education tends to be placed on the ability of acquiring practical geographic knowledge rather than the geographic information itself. And it is also another marked tendency that most learning activities in geography class are conducted on the basis of student-centered and the method of investigation. Teachers of the lower secondary schools in Belgium are trained in the School of Education as multi-major teachers, such as a teacher for biology-chemistry-geography or a teacher for history-sociology-geography. Teachers of the higher secondary school education are trained in the Department of Teacher Education in universities as solo-major teachers in that they are required to know more deeply to teach an advanced course of geography in the higher secondary schools. To improve the teacher education many folds of policies are adopted. One is that many in-service teachers are officially put into services of guiding and teaching teacher training. Another is that faculty members in charge of teacher training course are trying to level up the qualifications of teachers by rigorous disciplining.

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The Characteristics of Population Flows in kwangju Metropolitan Area (光州 中心의 人口移動 特性에 관한 硏究)

  • Chouh, Hae-Chong
    • Journal of the Korean Geographical Society
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    • v.28 no.1
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    • pp.40-57
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    • 1993
  • This paper aims to show the various aspects of migration in Kwangju merropolitan area, southwestern Korea, for a period of years 1980-1985. Migratory patterns are spatially extensive in countryside around Kwanfju, and due to high accessibility to the metropolitan area urban implosion emerges in the city. In Chonnam province where Kwangju is loca-ted, all cities and counties except for such in-dustrial areas as Yochon, and Kwangyang are experiencing population losses in terms of net migration by survival rate methods. Kwangju is the exceptionally one of in-migration areas in Chonnam, though its central part(Dong-Gu) is also an out-migrated area. Predominantly in-migration urban areas have high proportions of a student age group between 15-19 years, and that reflects the importance of the educational factor in migration analysis. The municipal authorities of Kwangju are planning to block the way of the middle sxhool students who live in the outskirts of Kwangju to entrance to high school in the city. Thant may stir up migrations into Kwangju for the elementary and middle school students, because the city id expected to provide educational opportunities higher and better than remaining Chonnam areas. Population of Kwangju would, therefore, grow as the students migrate into the city. The findings on the residential intra-city movement in selected 5 Dongs indicate that implications of a short-distance movement re noteworthy; neighbour to neighbour, and the nearest stop in the way from the outer Kwangju as well. Trends in a short-distance movement are in accord with Ravensteins's "law of migra-tion". But in casw of the inter-provincial migra-tion to Kwangju, the number of in-migrants from remoter Seoul is more than that from nearer Chonbuk province. Therefore it supports the fact that the movement between capital region and far off local cities overcomes a distance barrier. The temporary mobility for a day has been increased as the standard of living has improved and it reaches a peak on weekend or on con-secutive holidays. The number of temporal movers to Kwangju from capital region and Yongnam area, southeastern Korea has a greatincrease in terms of the frequency of the passengers' mobility, in particular on Myongjol(the ethnic and traditional festival day) in com-parison with on weekdays. By comparison with two largest Myongjols, the number of movers is more on Chusok(The Full Moon festival on lunar August) than on Sol (lunar new year's day). Annual peak point of weekday movers appears in August because of summer vacation. But the lowest one appears in June, which is related to the busy farming season. A patients' move for medical services in on the increase with a change of living conditions. It is especially true in the industrial counties such as Kwangyang and Yochon. By way of conclusion, it should be pointed out that one of the problems we face in survey of migration volume by the survival rate method is that the survival rate somtimes exceeds the value 1.0, in normal states of which should be under 1.0. it may be due to the shortcoming from the census statistics. We should not give therefore too much stress on the importance of migrations or moves as an element of changes in spatial pattern. In cinclusion, the results of the study show some geographic facts as the followings: 1. One of the outstanding phenomena in all types of movement is the seletivity of ages. The most important factors are related to education and employment. 2. Short-distance movement is carried out in accordance with Ravenstein's law, but in case long-distance movement, in-migration from capital region is prominent in spite of remoten-ces. The gravity between large cities such as Kwangju and Seoul, which has a frequent human movenent, causes urban implosion of small cities between those cities. 3. The temporary mobility for a day, in con-trast to that of permanent movement, is more related to transportation, and its volumes and annual variations are a large-scale. 4. Passengers' mobility is high in industrial cities. And the scope of patients' mobility is narrower than passengers'.

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Injuries and Prevention methods Associated with In-Line Skate (인라인 스케이트시 발생한 손상 밑 예방)

  • Lim Hong Chul;Chun Seung Joo;Rho Young Jin;Hwang Jin Ho;Park Chan Eung;Kim Tae Un
    • Journal of Korean Orthopaedic Sports Medicine
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    • v.2 no.2
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    • pp.163-167
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    • 2003
  • Purpose: The purpose of this study is to describe causes and injury mechanisms during inline skating and to find preventive measures .Materials and Methods: We have carefully selected 57 patients who have been treated in our hospital and nearby hospital. There are 37 males and 20 females, and mean age is 9 years 9 months (range,6-40 years old) . We have meticulously investigated their injured sites, their favorite location for inline skating , their use of protective means while they were on the wheels and their injury mechanisms . Results: Injury consisted of 50 fractures,1 meniscal tear,2 medial collateral ligament rupture and 4 contusion or sprain. Fracture sites varied as follows : 33(66$\%$) cases in distal radius and ulna,5(10$\%$) in elbow. 3(6$\%$) in diaphysis of humerus, etc Location at the time of injury varied as follows : 22 cases(39$\%$) in their apartment complex, 19 cases in (33$\%$) narrow streets, and 16 cases(28$\%$) in parks Only five patients admitted that any means of protection were used.2 cases only had knee pad on , 1 case put on elbow pad in addition, and 2 cases put on wrist guard as well. However none of the patients had helmet on Conclusion: We would strongly like to stress the importance of using sufficient protections and of choosing area where it is safe to ride, in order to reduce the risk of accidents. In addition, continuous and effective prior education from inline skate circles may be in order before riding the inline skate.

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Application of the Homogenization Analysis to Calculation of a Permeability Coefficient (투수계수 산정을 위한 균질화 해석법의 적응)

  • 채병곤
    • Journal of Soil and Groundwater Environment
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    • v.9 no.1
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    • pp.79-86
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    • 2004
  • Hydraulic conductivity along rock fracture is mainly dependent on fracture geometries such as orientation, aperture, roughness and connectivity. Therefore, it needs to consider fracture geometries sufficiently on a fracture model for a numerical analysis to calculate permeability coefficient in a fracture. This study performed new type of numerical analysis using a homogenization analysis method to calculate permeability coefficient accurately along single fractures with several fracture models that were considered fracture geometries as much as possible. First of all, fracture roughness and aperture variation due to normal stress applied on a fracture were directly measured under a confocal laser scaning microscope (CLSM). The acquired geometric data were used as input data to construct fracture models for the homogenization analysis (HA). Using the constructed fracture models, the homogenization analysis method can compute permeability coefficient with consideration of material properties both in microscale and in macroscale. The HA is a new type of perturbation theory developed to characterize the behavior of a micro inhomogeneous material with a periodic microstructure. It calculates micro scale permeability coefficient at homogeneous microscale, and then, computes a homogenized permeability coefficient (C-permeability coefficient) at macro scale. Therefore, it is possible to analyze accurate characteristics of permeability reflected with local effect of facture geometry. Several computations of the HA were conducted to prove validity of the HA results compared with the empirical equations of permeability in the previous studies using the constructed 2-D fracture models. The model can be classified into a parallel plate model that has fracture roughness and identical aperture along a fracture. According to the computation results, the conventional C-permeability coefficients have values in the range of the same order or difference of one order from the permeability coefficients calculated by an empirical equation. It means that the HA result is valid to calculate permeability coefficient along a fracture. However, it should be noted that C-permeability coefficient is more accurate result than the preexisting equations of permeability calculation, because the HA considers permeability characteristics of locally inhomogeneous fracture geometries and material properties both in microscale and macroscale.

Growth and Population Dynamics of Zostera marina Due to Changes in Sediment Composition in the Seomjin Estuary, Korea (퇴적물 성상 변화에 따른 섬진강 하구 거머리말의 생장 특성)

  • kim, Jeong Bae;Park, Jung-Im;Lee, Won-Chan;Lee, Kun-Seop
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.20 no.1
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    • pp.43-52
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    • 2015
  • The growth and population dynamics of eelgrass (Zostera marina) due to changes in sediment composition were examined in the lower intertidal zone of the Seomjin Estuary, Korea. We surveyed environmental factors such as water temperature, underwater irradiance, main types and organic content of sediment, tidal exposure, and nutrient concentrations in the water column and sediment pore water, in relation to the shoot density, biomass, morphological characteristics, and growth of Z. marina inhabiting lower intertidal zones. The survey was conducted monthly from May to December of 2004 and 2009. The water temperature showed obvious seasonal trends in both study years. Underwater irradiance was significantly higher in 2009 than in 2004. Tidal exposure was not significantly different between 2004 and 2009. The sediment was muddy-sand in 2004 but became sandy and with a significantly lower organic content in 2009. Water column $NH_4{^+}$ concentrations were significantly higher in 2004 than in 2009. Sediment pore water $NO_3{^-}+NO_2{^-}$ concentrations were significantly higher in 2009 than in 2004. Other nutrient concentrations did not differ significantly between 2004 and 2009. Morphological characteristics, including eelgrass length and leaf width were significantly lower in 2009 than in 2004. Eelgrass shoot height, leaf length, and sheath length showed typical seasonal patterns, increasing in early summer and decreasing in autumn, in both years. Vegetative shoot density was not significantly different between 2004 and 2009, while the biomass of individual plant parts and the total biomass were significantly lower in 2009. Eelgrass leaf productivity did not differ between years, but leaf turnover time was significantly shorter in 2009 than in 2004. Eelgrass downsizing and decreased turnover time in 2009 compared to 2004 indicate more effective adaptations to the stress of long-term changes in sediment composition. Overall, results suggest that changes in sediment composition can be a limiting factor for seagrass growth in the intertidal zone.