• 제목/요약/키워드: population control

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세균의 적정밀도 인식을 통한 신호전달 및 신호전달 차단 연구 (Bacterial Quorum Sensing and Anti-Quorum Sensing)

  • 박순양;이정기
    • 한국미생물·생명공학회지
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    • 제32권1호
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    • pp.1-10
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    • 2004
  • Many bacteria monitor their population density and control the expression of specialized gene sets in response to bacterial cell density based on a mechanism referred to as quorum sensing. In all cases, quorum sensing involves the production and detection of extracellular signaling molecules, auto inducers, as which Gram-negative and Gram-positive bacteria use most prevalently acylated homoserine lactones and processed oligo-peptides, respectively. Through quorum-sensing communication circuits, bacteria regulate a diverse array of physiological functions, including virulence, symbiosis, competence, conjugation, antibiotic production, motility, sporulation, and biofilm formation. Many pathogens have evolved quorum-sensing mechanisms to mount population-density-dependent attacks to over-whelm the defense responses of plants, animals, and humans. Since these AHL-mediated signaling mechanisms are widespread and highly conserved in many pathogenic bacteria, the disruption of quorum-sensing system might be an attractive target for novel anti-infective therapy. To control AHL-mediated pathogenicity, several promising strategies to disrupt bacterial quorum sensing have been reported, and several chemicals and enzymes have been also investigated for years. These studies indicate that anti-quorum sensing strategies could be developed as possible alternatives of antibiotics.

What Roles should Population-based Cancer Registries be Playing in the 21st Century? Reflections on the Asian Cancer Registry Forum, Bangkok, February 2014

  • Roder, David
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권5호
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    • pp.1895-1896
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    • 2014
  • Cancer registries have fundamental roles in cancer surveillance, research, and health services planning, monitoring and evaluation. Many are now assuming a broader role by contributing data for health-service management, alongside data inputs from other registries and administrative data sets. These data are being integrated into de-identified databases using privacy-protecting data linkage practices. Structured pathology reporting is increasing registry access to staging and other prognostic descriptors. Registry directions need to vary, depending on local need, barriers and opportunities. Flexibility and adaptability will be essential to optimize registry contributions to cancer control.

알코올 소비와 음주교통사고 (Alcohol Consumption and Alcohol-involved Traffic Accident)

  • 이원재
    • 보건교육건강증진학회지
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    • 제14권2호
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    • pp.69-94
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    • 1997
  • Recently, occurrence of alcohol-involved traffic accidents is increasing while all the accidents by violation of law except drunk driving. Traffic accidents by drunk driving has a great external cost. In detecting drunk driving, blood alcohol content Many studies reported close correlation between blood alcohol content and traffic accidents by drunk driving. The risk of traffic accidnet increases exponentially as blood alcohol content increases. To control traffic accidents by drunk driving, decide target population. Heavy drinkers are few and responsible for a small part of the loss while casual drinkers are many and responsible for a large part of the loss. Casual drinkers need to be included in the targer population for the control of traffic accident by drunk driving. Stragegies to reduce the quantity of alcohol consumed, change the pattern of drink, such as frequency of drinking, raise of perceived risk of accident need to be sought.

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Duality in an Optimal Harvesting Problem by a Nonlinear Age-Spatial Structured Population Dynamic System

  • Kim, Yong-Kuk;Lee, Mi-Jin;Jung, Il-Hyo
    • Kyungpook Mathematical Journal
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    • 제51권4호
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    • pp.353-364
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    • 2011
  • Duality in the optimal harvesting for a nonlinear age-spatial structured population dynamic model is studied in the framework of optimal control problem. In this paper the duality theory that displays the conjugacy of the primal problem is established and an application is given. Duality theory plays an important role in both optimization theory and methodology and the results may be applied to a realistic biological system on the point of optimal harvesting.

Sampling, Surveillance and Forecasting of Insect Population for Integrated Pest Management in Sericulture

  • Singh, R.N.;Maheshwari, M.;Saratchandra, B.
    • International Journal of Industrial Entomology and Biomaterials
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    • 제8권1호
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    • pp.17-26
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    • 2004
  • Pest monitoring through field surveys and surveillance helps in forecasting the population build up of pest. It reduces the load of pesticides application and forms the basis of Integrated Pest Management in sericulture. Common sampling techniques for quantifying pest populations and damage caused by them are reviewed emphasizing the need for quick and simple sampling methods. Various direct and indirect sampling methods for establishing pest populations are discussed and methods have been discussed to use indirect sampling method under IPM programme in sericulture. The use of pheromone lures and traps forms one of the important ingredients of integrated pest management, which calls for integration of all available methods in a cost effective and environmental friendly manner offering consistent efficacy. Silk-worms feed on the variety of silk host plants and spin cocoons. Each silk host plant is attacked in the field by number of insect pest species. Several pests are common to mulberry, tasar, oak tasar, muga and eri host plant but pest status and seasonal abundance differs from each crop. The key pests are serious perennially occurring persistent species which cause considerable yield loss every year on large areas and require control measure. Regular occurrence of minor pest is noticed but sudden increase in its population is not known. The occasional pests are sporadic but potential causing sufficient damage. Silk losses due to attack of all the pests have not been calculated. However, information on pest biology and ecology, and control practices being practiced is available but the period of outbreak of major pests and predators on silkworms and its host plant needs to be reinvestigated. Pest and predators forecasting based on surveillance information may provide an opportunity to minimize the losses, particularly to reduce expenditure involved in pest management.

생식형불일치 유형에 따른 국내 프루텔고치벌(Cotesia plutellae)의 유전적 위치 (Genetic Identity of a Korean Isolate of an Endoparasitoid Cotesia plutellae(Hymenoptera: Braconidae), Among Reproductive Incompatibility Types)

  • 박정아;김용균
    • 한국응용곤충학회지
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    • 제46권1호
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    • pp.57-62
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    • 2007
  • 자생밀도의 증가를 위해 도입되는 생물적 방제인자를 선정하는 데 있어서 생식형불일치는 주요한 요인이다. 배추좀나방(Plutella xylostella(L.))에 대한 효과적 생물적방제 인자로서 프루텔고치벌(Cotesia plutellae (Kurdjumov))은 집단 사이에 생식형불일치로 크게 두 생식형집단으로 분류되었다. 본 연구는 국내 서식하는 특정 프루텔고치벌 집단에 대해서 형태적 및 미토콘드리아 염기서열 지표분석을 실시하였으며, 이 결과 국내 집단이 기존에 보고된 두 생식형집단에 비해 형태적 형질과 분자지표에서 뚜렷한 차이를 보였다. 이러한 결과는 국내 프루텔고치벌 집단이 새로운 생식형집단일 수 있다는 것을 제시하였다. 또한 본 연구 결과는 외래 프루텔고치벌의 도입을 위해서는 국내 자생종과의 생식형불일치 가능성을 중요하게 고려해야 한다고 보고한다.

ENHANCED BIOREMEDIATION AND MODIFIED BACTERIAL COMMUNITY STRUCTURE BY BARNYARD GRASS IN DIESEL-CONTAMINATED SOIL

  • Kim, Jai-Soo;Min, Kyung-Ah;Cho, Kyung-Suk;Lee, In-Sook
    • Environmental Engineering Research
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    • 제12권2호
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    • pp.37-45
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    • 2007
  • Phytoremediation has been used effectively for the biodegradation of oil-based contaminants, including diesel, by the stimulation of soil microbes near plant roots (rhizosphere). However, the technique has rarely been assessed for itsinfluence on soil microbial properties such as population, community structure, and diversity. In this study, the removal efficiency and characteristics of rhizobacteria for phytoremediation of diesel-contaminated soils were assessed using barnyard grass (Echinochloa crusgalli). The concentration of spiked diesel for treatments was around $6000\;mg\;kg^{-1}$. Diesel removal efficiencies reached 100% in rhizosphere soils, 76% in planted bulk soils, and 62% in unplanted bulk soils after 3weeks stabilization and 2 months growth(control, no microbial activity: 32%). The highest populations of culturable soil bacteria ($5.89{\times}10^8$ per g soil) and culturable hydrocarbon-degraders($5.65{\times}10^6$ per g soil) were found in diesel-contaminated rhizosphere soil, also yielding the highest microbial dehydrogenase. This suggests that the populations of soil bacteria, including hydrocarbon-degraders, were significantly increased by a synergistic rhizosphere + diesel effect. The diesel treatment alone resulted in negative population growth. In addition, we investigated the bacterial community structures of each soil sample based on DGGE (Denaturing Gel Gradient Electrophoresis) band patterns. Bacterial community structure was most influenced by the presence of diesel contamination (76.92% dissimilarity to the control) and by a diesel + rhizosphere treatment (65.62% dissimilarity), and least influenced by the rhizosphere treatment alone (48.15% dissimilarity). Based on the number of distinct DGGE bands, the bacterial diversity decreased with diesel treatment, but kept constant in the rhizosphere treatment. The rhizosphere thus positively influenced bacterial population density in diesel-contaminated soil, resulting in high removal efficiency of diesel.

Polymorphism of the DNA Repair Gene XRCC1 (Arg194Trp) and its role in Colorectal Cancer in Kashmiri Population: a Case Control Study

  • Nissar, Saniya;Sameer, Aga Syed;Rasool, Roohi;Chowdri, Nissar A;Rashid, Fouzia
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권15호
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    • pp.6385-6390
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    • 2015
  • Background: Genetic polymorphisms in DNA repair genes may influence individual variation in DNA repair capacity, which may be associated with risk of developing cancer. For colorectal cancer the importance of mutations in mismatch repair genes has been extensively documented. Materials and Methods: In this study we focused on the Arg194Trp polymorphism of the DNA repair gene XRCC1, involved in base excision repair (BER) and its role in colorectal cancer in Kashmiri population. A case-control study was conducted including 100 cases of colorectal cancer, and 100 hospital-based age- and sex-matched healthy controls to examine the role of XRCC1 genetic polymorphisms in the context of colorectal cancer risk for the Kashmiri population. Results: Genotype analysis of XRCC1 Arg194Trp was conducted with a restriction fragment length polymorphism (RFLP) method. The overall association between the XRCC1 polymorphism and the CRC cases was found to be significant (p < 0.05) with both the heterozygous genotype (Arg/Trp) as well as homozygous variant genotype (Trp/Trp) being moderately associated with the elevated risk for CRC [OR=2.01 (95% CI=1.03-3.94) and OR=5.2(95% CI=1.42-19.5)] respectively. Conclusions: Our results suggest an increased risk for CRC in individuals with XRCC1 Arg194Trp polymorphism suggesting BER repair pathway modulates the risk of developing colorectal cancer in the Kashmiri population.

Profile of Lung Cancer in Kuwait

  • El-Basmy, Amani;Al-Mohannadi, Shihab;Al-Awadi, Ahmed
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권10호
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    • pp.6181-6184
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    • 2013
  • Background: Lung cancer is the most frequent cancer in males and the fourth most frequent site in females, worldwide. This study is the first to explore the profile of lung cancer in Kuwait. Materials and Methods: Cases of primary lung cancer (Kuwaiti) in Kuwait cancer Registry (KCR) were grouped in 4 periods (10 years each) from 1970-2009. Epidemiological measures; age standardized incidence rate (ASIR) with 95% confidence intervals (CI), Standardized rate ratio (SRR) and Cumulative risk and Forecasting to year 2020-2029 used for analysis. Results: Between years, 2000-2009 lung cancer ranked the 4th and the 9th most frequent cancer in males and females respectively. M:F ratio 1:3. Mean age at diagnosis (95%CI) was 65.2 (63.9-66.4) years. The estimated risk of developing lung cancer before the age of 75 years in males is 1.8% (1/56), and 0.6 (1/167) in females. The ASIR for male cases was 11.7, 17.1, 17.0, 14.0 cases/100,000 population in the seventies, eighties, nineties and in 2000-2009 respectively. Female ASIR was 2.3, 8.4, 5.1, 4.4 cases/100,000 population in the same duration. Lung cancer is the leading cause cancer death in males 168 (14.2%) and the fifth cause of death due to cancer in females accounting for 6.1% of all cancer deaths. The ASMR (95%CI) was 8.1 (6.6-10.0) deaths/100,000 population and 2.8 (1.3-4.3) deaths/100,000 population in males and females respectively. The estimated Mortality to incidence Ratio was 0.6. Conclusions: The incidence of lung cancer between years 2000-2009 is not different from that reported in the seventies. KCR is expecting the number of lung cancer cases to increase.

Association of a p53 Codon 72 Gene Polymorphism with Environmental Factors and Risk of Lung Cancer: a Case Control Study in Mizoram and Manipur, a High Incidence Region in North East India

  • Saikia, Bhaskar Jyoti;Das, Mandakini;Sharma, Santanu Kumar;Sekhon, Gaganpreet Singh;Zomawia, Eric;Singh, Yanglem Mohen;Mahanta, Jagadish;Phukan, Rup Kumar
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권24호
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    • pp.10653-10658
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    • 2015
  • Background: A very high incidence of lung cancer is observed in Mizoram and Manipur, North East India. We conducted a population based case control study to establish associations of p53 codon 72 polymorphisms and interactions with environmental factors for this high incidence. Material and Methods: A total of 272 lung cancer cases and 544 controls matched for age (${\pm}5years$), sex and ethnicity were collected and p53 codon 72 polymorphism genotypes were analyzed using a polymerase chain based restriction fragment length polymorphism assay. We used conditional multiple logistic regression analysis to calculate adjusted odds ratios and 95% confidence intervals after adjusting for confounding factors. Results: p53 Pro/Pro genotype was significantly associated with increased risk of lung cancer in the study population (adjusted OR=2.14, CI=1.35-3.38, p=0.001). Interactions of the p53 Pro/Pro genotype with exposure to wood smoke (adjusted OR=3.60, CI=1.85-6.98, p<0.001) and cooking oil fumes (adjusted OR=3.27, CI=1.55-6.87, p=0.002), betel quid chewing (adjusted OR=3.85, CI=1.96-7.55, p<0.001), tobacco smoking (adjusted OR=4.42, CI=2.27-8.63, p<0.001) and alcohol consumption (adjusted OR=3.31, CI=1.10-10.03, p=0.034) were significant regarding the increased risk of lung cancer in the study population. Conclusions: The present study provided preliminary evidence that a p53 codon 72 polymorphism may effect lung cancer risk in the study population, interacting synergistically with environmental factors.