• Title/Summary/Keyword: free-living

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Two new free-living marine nematodes of the genus Belbolla (Nematoda, Enoplida, Enchelidiidae) from a shallow subtidal benthic habitat of the outermost islands of Korea

  • Hyun Soo Rho;Hyo Jin Lee;Heegab Lee;Chang Geun Choi
    • Korean Journal of Environmental Biology
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    • v.39 no.4
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    • pp.423-434
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    • 2021
  • Two new free-living marine nematodes of the genus Belbolla Andrássy, 1973 belonging to family Enchelidiidae are newly described based on specimens obtained from a shallow subtidal sediment of the western and southern outermost islands of Korea. Belbolla koreensis sp. nov. differs from other species of the genus by the combination of the following characteristics: longer body length (3,080-3,462 ㎛ long), eight oesophageal bulbs in the posterior region of pharynx, well-developed two winged precloacal supplements (anterior precloacal supplement slightly longer than posterior one: 47-59 ㎛ vs. 43-46 ㎛ long), strongly arcuated, very thick, L-shaped spicule (122-127 ㎛ long, 1.7-1.9 anal body diameter(a.b.d.) long) with three separated blunt distal tips, and well-developed relatively long cylindrical shaped gubernacular apophysis with blunt teeth covering two thirds of the dorsal margin (57-58 ㎛ long, 0.8-0.9 a.b.d. long). Belbolla hoonsooi sp. nov. is characterized by the following combination of characteristics: longer body length (3,494 ㎛ long), eight oesophageal bulbs in the posterior region of pharynx, well-developed two winged precloacal supplements (anterior precloacal supplement slightly longer than posterior one: 43 ㎛ vs. 36 ㎛ long), strongly arcuated, L-shaped spicule (119 ㎛ long, 1.5 a.b.d. long) with three separated blunt distal tip, and well-developed relatively long inverted triangle shaped gubernacular apophysis with blunt teeth covering half of the dorsal margin (45 ㎛ long, 0.6 a.b.d. long). Detailed morphological characteristics and illustrations of two new Belbolla nematodes from the Korean seawaters were provided by differential interference contrast microscopy. Comparative tables on biogeographical and morphological characteristics of Belbolla species are also provided herein.

Antiamoebic activities of flavonoids against pathogenic free-living amoebae, Naegleria fowleri and Acanthamoeba species

  • Huong Giang Le;Tuan Cuong Vo;Jung-Mi Kang;Thu Hang Nguyen;Buyng-Su Hwang;Young-Taek Oh;Byoung-Kuk Na
    • Parasites, Hosts and Diseases
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    • v.61 no.4
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    • pp.449-454
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    • 2023
  • Free-living amoebae (FLA) rarely cause human infections but can invoke fatal infections in the central nervous system (CNS). No consensus treatment has been established for FLA infections of the CNS, emphasizing the urgent need to discover or develop safe and effective drugs. Flavonoids, natural compounds from plants and plant-derived products, are known to have antiprotozoan activities against several pathogenic protozoa parasites. The anti-FLA activity of flavonoids has also been proposed, while their antiamoebic activity for FLA needs to be emperically determined. We herein evaluated the antiamoebic activities of 18 flavonoids against Naegleria fowleri and Acanthamoeba species which included A. castellanii and A. polyphaga. These flavonoids showed different profiles of antiamoebic activity against N. fowleri and Acanthamoeba species. Demethoxycurcumin, kaempferol, resveratrol, and silybin (A+B) showed in vitro antiamoebic activity against both N. fowleri and Acanthamoeba species. Apigenin, costunolide, (-)-epicatechin, (-)-epigallocatechin, rosmarinic acid, and (-)-trans-caryophyllene showed selective antiamoebic activity for Acanthamoeba species. Luteolin was more effective for N. fowleri. However, afzelin, berberine, (±)-catechin, chelerythrine, genistein, (+)-pinostrobin, and quercetin did not exhibit antiamoebic activity against the amoeba species. They neither showed selective antiamoebic activity with significant cytotoxicity to C6 glial cells. Our results provide a basis for the anti-FLA activity of flavonoids, which can be applied to develope alternative or supplemental therapeutic agents for FLA infections of the CNS.

Physiological and Ecological Characteristics of Indigenous Soybean Rhizobia Distributed in Korea -II. Studies on Some Physiological Characteristics and Nitrogen Fixation Activity Under Free-Living Conditions of Indigenous Rhizobia (우리나라 토착대두근류균(土着大豆根瘤菌)의 분포상태(分布狀態)와 생리(生理) 및 생태학적(生態學的) 특성(特性) -제(第)II보(報) : 토착근류균(土着根瘤菌)의 질소고정력(窒素固定力)과 생리적특성(生理的特性)에 관(關)한 연구(硏究))

  • Ryu, Jin-Chang;Lee, Seong-Jae;Suh, Jang-Sun;Cho, Moo-Je
    • Korean Journal of Soil Science and Fertilizer
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    • v.19 no.2
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    • pp.157-165
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    • 1986
  • This experiment was conducted to find out the some physiological characteristics and nitrogen fixation activities under free-living conditions of indigenous rhizobia isolated from soybean-cultivated (30 fields) and un-cultivated (30 fields) soil. The results were summerized as follows: 1. In free-living condition, only 12.8% and 6.4% of the indigenous rhizobia isolated from soybean cultivated (133 strains) and un-cultivated (125 strains) soils were nitrogenase positive as more than 4 n mole $C_2H_4$ per tube per hour by acetylene reduction assay. 2. The acid-producing rhizobia on litmus milk test was observed to be 20% of the total 160 strains isolated from soybean cultivated soil but about 34% of 166 strains isolated from un-cultivated soil. And the serum zone positive strains were higher in the soybean un-cultivated soil than cultivated soil. 3. The population ratio of fast-to slow-growing indigenous rhizobia based on growth pattern of AMA medium was 35.6% to 64.4% of the total 346 strains. 4. The population of indigenous Rhizobium japonicum counted by MPN method was ranged from $9.2{\times}10^2$ cells per gram of soil in soybean un-cultivated soil to $2.3{\times}10^4$ cells per gram of soil soybean cultivated soil. The number of indigenous R. japonicum in 0-10cm depth of surface layer was higher than low layer.

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Development of an in vitro culture method for harvesting the free-living infective larvae of Strongyloides venezuelensis (베네수엘라분선충 (Strongyloides venezuelensis Brumpt, 1934) 자유생활형 유충의 시험관 내 배양 기술 개발)

  • ;M.
    • Parasites, Hosts and Diseases
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    • v.36 no.1
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    • pp.15-22
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    • 1998
  • An in uitro culture technique was established for harvesting Strongwloides venezuelensis free-living infective larvae using a nutrient broth medium as a substitute for rat-feces in polyvinyl culture bags ($10{\;}{\times}{\;}12{\;}cm$). The egg hatch rate V) in sterile saline at different incubation temperatures (X) was expressed as the quadratic function, Y = $-0.192X^2$ + 8.673x - 19.550 (r = 0.901). The highest (100%) egghatch rate was observed at $25^{\circ}C$. A significant difference (p<0.05) in development rate W) of free-living infective larvae was observed between different concentrations of nutrient broth (X) which was highest (20.6%1 in 0.12% nutrient broth concentrations, incubated at $20^{\circ}C$ for 5 days [Y = $-864.032X^2$ + 245.995X- 0.560 (r = 0.875)]. Yields (Y) of infective larvae were observed relatively high when the culture medium was incubated at higher temperatures (X) which peaked at $25^{\circ}C$ (20.0%) than at lower temperatures. $15^{\circ}C$M (10.9%) and $20^{\circ}C$ (18.1%) [Y = $-0.189X^2$ + 8.387x- 72.795 (r = 0.981)]. The period W) required for the development of infective larvae decreased with higher incubation temperatures (X) [Y = $0.035X^2$ - 2.025X + 32.375 (r = 0.995)] The highest yield (19.2%) of infective larvae was obtained from culture bag inoculated with 15.000 eggs than with below and over 15,000 eggs in 0.12% nutrient broth and incubated at $25^{\circ}C$ for 4 days. The newly adapted culture method (from egg to third-stage larva) may be useful as a bio-bar/bioassay system for screening new chemical products, anthelmintics and pesticides, as well as for parasito immunological studies with Strongwloides species.

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Studies on Resistance of Embryonated Eggs, First-Stage Larvae, and Free-Living Infective Larvae of Metastrongyus apri to Different Temperatures (돈폐충(豚肺蟲) 자충(仔蟲)의 온도저항성(溫度抵抗性)에 관(關)한 연구(硏究))

  • Lee, Hyun Beom
    • Korean Journal of Veterinary Research
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    • v.15 no.1
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    • pp.51-55
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    • 1975
  • In this study two sets of experiments were undertaken. Firstly, the embryonated eggs and first-stage larvae, sprayed in disinfected soil, were exposed to different temperatures. Then, the viabilities of them were weekly determined by inoculating the soil to earthworms, Eisenia foetida. Secondly, the infective larvae, seperated from the earthworms and suspended in tap water, were also exposed to different temperatures and their viabilities were checked microscopically at weekly intervals. The results were summerized as follows: 1. The maximum longevities of embryonated eggs and first-stage larvae were determined as 1 week at $35^{\circ}C$, over 36 weeks at $25^{\circ}C$, $15^{\circ}C$, and $5^{\circ}C$, 32 weeks at $-5^{\circ}C$, and under 1 week at $-15^{\circ}C$. 2. The mean numbers of infective larvae detected from the test earthworms were greatest at $5^{\circ}C$, and decreased with rise or fall of the temperature. 3. Infective larvae freed from the intermediate host were able to survive for 2 weeks at $25^{\circ}C$ and 3 weeks at $15^{\circ}C$. However, they lost their viabilities in a week at $35^{\circ}C$, $5^{\circ}C$, $-5^{\circ}C$, and $-15^{\circ}C$. 4. The number of living infective larvae at $15^{\circ}C$ was greater than at $25^{\circ}C$.

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A Study on Introduction System of LED Lighting the Possibility of Application in Residential Space (디지털 주거공간에 적용 가능한 LED 조명의 도입방안에 관한 연구)

  • Chun, Jung-Oh;Han, Hae-Ryon
    • Proceedings of the Korean Institute of Interior Design Conference
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    • 2006.05a
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    • pp.189-192
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    • 2006
  • The development of digital technology makes our life more convenient in our lives and its calmness promotes the qualify of our life. Digital-home-automation system lets indoor-living more free, safe and clear so that it really has come true our life style that considers our mind and healthy to be important. Moreover, LED light source that combines the semiconductor with the digital technology has been tried as a current indoor illumination. Also the introduction of the light which has a high technology, like LED light, has been required in living space. It shows that it is very important to have an illuminated- plan which is accepted as well-developed technology. This study deals with the investigation into the user satisfaction of the existing residential area illumination and the investigation into the user satisfaction of the LED illumination being supplied for commercial area now. In the result, the fact is investigated that the user wants the introduction of the digital technology In the illumination because of a backward the residental area illumination in the circumstances being digital gradually. The inconvenience of the illumination used now should be minimized and the development of the LED illumination is a way satisfying the desire. The intended illumination project of the residential area should be accomplished according to the lifestyle of a changing residence.

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A Study on Introduction System of LED Lighting the Possibility of Application in Digital-home (디지털 홈에 적용 가능한 LED조명의 도입방안에 관한 연구)

  • Chun Jung-Oh;Han Hae-Ryon
    • Korean Institute of Interior Design Journal
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    • v.14 no.6 s.53
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    • pp.220-227
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    • 2005
  • The development of digital technology makes our life more convenient in our lives and its calmness promotes the qualify of our life. Digital-home-automation system lets indoor-living more free, safe and clear so that it really has come true our life style that considers our mind and healthy to be important. Moreover, LED light source that combines the semiconductor with the digital technology has been tried as a current indoor illumination. Also the Introduction of the light which has a high technology, like LED light, has been required in living space. It shows that it is very important to have an illuminated-plan which is accepted as well-developed technology This study deals with the investigation into the user satisfaction of the existing residential area illumination and the investigation Into the user satisfaction of the LED illumination being supplied for commercial area now. In the result, the fact is investigated that the user wants the introduction of the digital technology in the illumination because of a backward the residental area illumination in the circumstances being digital gradually. The inconvenience of the illumination used now should be minimized and the development of the LED illumination is a way satisfying the desire. The intended illumination project of the residential area should be accomplished according to the lifestyle of a changing residence.

Patterns of Vitamin-Mineral Supplement Usage by the Elderly in Korea (노년기의 비타민.무기질 보충제 복용 실태 조사)

  • 송병춘
    • Journal of Nutrition and Health
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    • v.30 no.2
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    • pp.139-146
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    • 1997
  • Use of the viamin-mineral supplements markedly increased with the awareness of diet and health. Data were collected from the self-administered questionnaire of 450 free living elderly, 60 to 94 years old, in Korea, to assess the relationships between socioeconomic variables, beliefs about nutrition, and the factors affecting gupplements usage. In addition, vitamin-mineral intakes through the supplements were calculated, and compared with RDA. 44.9% of the subjects took the vitamin-mineral supplements, and significantly higher percentage of women(49.3%) than men(38.1%) took supplements(p<0.05). The higher the education level, monthly pocket money, the percentage of supplements consumption was higher. People living in large cities took more supplements than those in small cities. One of the mainly cited reasons for taking supplements was to maintain health. The most favored nutrient supplements used by the subjects were in the order of vitamin B complex, vitamin E and Calcium, and vitamin-mineral intake through the supplements were much greater than RDA and ranges of their intakes were very wide. Vitamin B1 and vitamin E were observed to consume excessive amount(63 times of RDA and 40 times of RDA, respectively). The reasons for supplementation were often inappropriate and unreliable sources of information were used. Thus nutritional understanding and education of the elderly peopled are needed in regard to the use of vitamin-mineral supplements, and the relationship between adequate diet and good health.

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Living Experiences of Indian Adult Cancer Survivors - a Brief Report

  • Mohanti, Bidhu Kalyan;Kaur, Jaspreet
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.2
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    • pp.507-512
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    • 2015
  • Background: This pilot study looked into the physical, social, psychological and economic issues of Indian adult cancer survivors. Materials and Methods: Assumed cancer free patients, after cancer directed therapy (CDT), were assessed on the basis of a questionnaire developed by the investigators. The mental status of the survivors was elicited by modified MINI international neuro-psychiatric interview. This cross sectional assessment was conducted as a direct interaction with each patient for 30 to 45 minutes at a cancer hospital in 2012. Results: Thirty one adult cancer survivors participated in this study. Median age was 53 years with a median follow up duration of 21.8 months (Range 2.3-194.1 months). The majority (68%) did not receive financial support for treatment. Median interval after CDT to start of activity of daily living was 1.5 months (range: 0-24 months). Fatigue and loss of appetite were reported by 52% and 29% respectively. The cancer diagnosis and its treatment adversely impacted the financial condition in 42% of patients. Nineteen percent each showed social anxiety and post-traumatic stress disorder and another 13% patients reported depression. Conclusions: This prospective assessment highlights survivorship issues and the need to address those issues particularly in the context of developing countries where resources and manpower are limited.

Addressing Factors Associated with Arab Women's Socioeconomic Status May Reduce Breast Cancer Mortality: Report from a Well Resourced Middle Eastern Country

  • Donnelly, Tam Truong;Al Khater, Al-Hareth;Al Kuwari, Mohamed Ghaith;Al-Bader, Salha Bujassoum;Abdulmalik, Mariam;Al-Meer, Nabila;Singh, Rajvir;Fung, Tak
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.15
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    • pp.6303-6309
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    • 2015
  • Differences in socioeconomic status (SES) such as income levels may partly explain why breast cancer screening (BCS) disparities exist in countries where health care services are free or heavily subsidized. However, factors that contribute to such differences in SES among women living in well resourced Middle East countries are not fully understood. This quantitative study investigated factors that influence SES and BCS of Arab women. Understanding of such factors can be useful for the development of effective intervention strategies that aim to increase BCS uptake among Arab women. Using data from a cross-sectional survey among 1,063 Arabic-speaking women in Qatar, age 35+, additional data analysis was performed to determine the relationship between socioeconomic indicators such as income and other factors in relation to BCS activities. This study found that income is determined and influenced by education level, occupation, nationality, years of residence in the country, level of social activity, self-perceived health status, and living area. Financial stress, unemployment, and unfavorable social conditions may impede women's participation in BCS activities in well resourced Middle East countries.