Why do we get sick? Evolutionary Medicine

최재천 ( Jae Chun Choe ) 대한피부과학회 2023 대한피부과학회 학술발표대회집 Vol.74 No.2

Why do we get sick? Consilience between evolutionary biology and medicine

최재천 ( Jae Chun Choe ) 대한간학회 2010 Clinical and Molecular Hepatology(대한간학회지) Vol.16 No.4(S)

Thanks to recent developments in modern medicine, we know a lot about how we get sick. We have also made a lot of progress in coming up with technologies in how to cure some of the diseases. However, we still know little about why we get sick in the first place. Fever provides a heuristic case in point. Whenever we have a high fever, we act far too often like a doctor. Without questioning why we got a high fever, we take acetaminophen (e.g., Tylenol). Is this wise? Fever may be unpleasant but useful. It is an adaptive feature of our body shaped by natural selection specifically to fight infection. Matt Kluger, a physiologist at the University of New Mexico, conducted an experiment with lizards and showed that even so-called cold-blooded animals like lizards benefit from fever. When infected, the lizards seek out a place warm enough to raise their body temperature about 2 degrees Celsius. Animals do not evolve alone but in relation with other species. If we understand such coevolutionary relationships between species, e.g., between host and parasite species, we can come up with much more reasonable solutions for treating diseases. Paul Ewald published a book entitled Evolution of Infectious Diseases in 1994, in which explained the relationship between the mode of transmission and virulence of pathogens. Malaria is still among the greatest causes of human deaths, because Plasmodium, the agent that causes Malaria, is indirectly transmitted by mosquitoes as its middle host and the virulence can be high. On the other hand, the virulence of cold virus can not be so high, because the virulent strains of virus will immobilize the hosts and prevent them from spreading to other hosts. It should be obvious that many new approaches may be possible if we adopt evolutionary thinking to medical research. Darwinian medicine officially launched by the publication of the book, Evolution and Healing, by Randolph Nesse and George Williams in 1995, is an excellent case of consilience. Finally, Hippocrates and Darwin meet one another.

유전자를 아시나요? 법학과 생물학의 통섭

최재천(Choe, Jae-Chun) 한국법학원 2013 저스티스 Vol.- No.134

에메리개미 (Vollenhovia emeryi Wheeler)의 날개이형체의 유전체 크기 추정

노푸름,박소연,최재천,정길상,Noh, Pureum,Park, Soyeon,Choe, Jae Chun,Jeong, Gilsang Korean Society of Applied Entomology 2018 한국응용곤충학회지 Vol.57 No.4

에메리개미는 여왕개미와 수개미가 유전적으로 복제되어 번식한다고 알려져 있으며, 여왕개미의 날개형태가 장시형과 단시형으로 나타난다. 장시형은 정상적인 날개형태이고, 이보다 짧은 날개형태는 단시형이라고 한다. 장시형과 단시형 모두 한 종으로 취급되지만, 두 가지 점에서 종지위에 대한 조사가 필요하다. 첫째, 자연 상태에서는 두 날개형이 함께 발견되지 않고, 둘째, 날개형이 육안으로 뚜렷하게 구분된다. 또한 복제되어 번식한 여왕개미가 단수체인지 배수체인지 조사가 필요하다. 따라서 우리는 본 연구에서 에메리개미 유전체 크기를 추정하여 두 날개형은 동종이며, 여왕개미는 배수체임을 확인하였다. In Vollenhovia emeryi (Hymenoptera: Myrmicinae), the queen and the male are known to be clonally reproduced. Its colonies can be classified into the two morphs with the wing length of the queen caste. The morph with normal wings is called the long-winged and the other the short-winged that is brachypterous. Even though the two morphs are considered a species, investigation on the species status of the two morphs was suggested with natural separation in nature and the distinctive wing morphology. It has yet to be determined whether the clonally reproduced queen caste is haploid or diploid. Our data clearly show that the two morphs are the same species and the queen caste is diploid on the basis of the genome size data comparison.

Detection of antibiotic-resistant Escherichia coli from the feces of the Oriental magpie nestlings

Yong Woo Kim(김용우),Jae Chun Choe(최재천),Piotr G. Jablonski(피오트르 야브원스키),Sang-im Lee(이상임) 한국조류학회II 2020 한국조류학회지 Vol.27 No.1

항생제 내성 유전자를 지닌 박테리아의 출현은 전세계적으로 인간과 야생동물 모두에게 큰 영향을 미칠 수 있는 중요한 문제 중 하나이다. 선행연구에서는 도시환경에 서식하는 야생조류가 의료시설이나 축산시설에서 널리 사용되는 항생제에 저항성을 갖는 박테리아에 노출될 가능성이 있고, 야생조류가 항생제 저항성 유전자의 운반체 역할을 할 가능성이 있음을 시사하였다. 한국에 사는 까치는 사람이 사는 도시환경에 잘 적응한 동물이므로, 까치 역시 항생제 저항성 유전자를 운반할 가능성이 있다고 예측할 수 있다. 이번 연구에서는 서울대학교 캠퍼스에서 태어난 까치 유조(幼鳥) 10마리의 분변 시료에서 세 가지 종류의 항생제에 대해 저항성을 가지는 유전자를 지닌 대장균(Escherichia coli)이 발견됨을 확인하였으며, 한 가지 이상의 항생제에 저항성을 가지는 대장균을 갖는 개체도 있음을 확인하였다. 이 결과는 인간과 가까운 환경에서 사는 야생조류인 까치가 항생제 저항성 유전자를 지닌 대장균에 노출되어 있음을 보여준다. 그러나 까치가 어떻게 항생제 저항성 미생물을 체내에 습득하게 되는지를 파악하기 위해서는 도시화된 정도가 다른 여러 환경에서 서식하는 까치와, 까치와 같이 도시환경에서 서식하는 다른 야생조류가 얼마나 항생제 저항성 미생물을 보유하고 있는지에 대한 후속 연구가 수행되어야 할 것이다. Appearance of drug-resistant bacteria is one of the most important issues worldwide that greatly impact both humans and wildlife. Previous studies proved that wild birds inhabiting in urban areas can be exposed to antibiotic-resistant bacteria, whose resistance might be derived from the antibiotics widely used in the medical facilities and farming areas. In these environments, wild birds can be a spreading vector for the resistance genes among the environmental bacteria. The Oriental magpie (Pica serica) is one of the wildlife species well known for high adaptability to urban habitats. Therefore, one can predict that the Oriental magpie is a potential carrier of the antibiotic-resistant microbes. In this study, we conducted disk susceptibility test and PCRs for antibiotic resistance genes and detected Escherichia coli carrying resistance to three antibiotic agents from the feces of 10 hatchlings and fledglings of the Oriental magpie living in the campus of Seoul National University (SNU). In addition, some individuals showed multi drug resistance. Our results show that nestlings and fledglings of the Oriental magpie are exposed to Escherichia coli harboring resistance to one or more antibiotic agents. In order to understand the origin and the transfer mechanisms of these microbes, more thorough investigation on the exposure of wildlife species living in a range of urban-rural gradients to the antibiotic resistant microbes should be conducted.

한국산 깡충거미과(Araneae, Salticidae)의 2 미기록종

장수진(Soo Jin Jang),최재천(Jae Chun Choe),김주필(Joo-Pil Kim) 한국거미연구소 2007 한국거미 Vol.23 No.2

  깡충거미과의 골풀무깡충거미속 1종인 Helicius chikuni, 1999 ~(안면골풀무깡충거미)와 두줄깡충거미속의 1종인 Plexippus petersi, 1878 ~(황색줄무늬깡충거미)가 한국산 미기록종으로 밝혀져 기재되어 보고한다. 이로 한국산 깡충거미과는 34속의 73종으로 기록된다.   In Korean spider fauna, two salticid spiders, Helicius chikuni (Logunov & Marusik, 1999) and Plexippus petersi (Karsch, 1878), are newly recorded. We provide detailed morphological descriptions and illustrations of females for each species. As a result, Korean Salticidae comprises of 73 species under 34 genera.

CFD 해석을 통한 까치 둥지 형상의 환경적응성에 관한 연구

유승천(Seung Cheon Yu),권은비(Eun Bi Kwon),이상임(Sang Im Lee),최재천(Jae Chun Choe),최재붕(Jae Boong Choi) 대한기계학회 2008 대한기계학회 춘추학술대회 Vol.2008 No.5

Surviving for 35 billion years in the earth, living things have developed their organisms to fit the wild nature. In the earlier study, Korean magpie's nests data are collected and clarified such as shape, size, length and etc. From the obtained data, the direction of axis in horizontal section of their nests is observed to match with that of the strongest wind at the nesting site. The computational fluid dynamics analysis is conducted to validate the assumption through 20 finite element model of horizontal ellipse section. Increasing the length of the longest horizontal axis of the nests by 10% reduced the flow velocity at the midpoint of nest cup by 50%. This would help magpies to preserve heat that is crucial for the growth and survival of their offspring in the nest due to optimize the wind blocking. The finite element method result explains the way of evolution for magpie's nest construction.

CFD 해석을 이용한 세스랑게 구조물의 환기효과에 대한 연구

김선혜(Sun-Hye Kim),김태원(Tae-Won Kim),최재천(Jae-Chun Choe),최재붕(Jae-Boong Choi) 대한기계학회 2008 대한기계학회 춘추학술대회 Vol.2008 No.5

Human beings have developed technology and knowledge by learning from nature. Especially, in the construction field, a mound in the prehistoric age is similar to an ant hill and a woodchuck nest'. Moreover, the Beijing National Stadium for 2008 summer Olympics is a nest-like skeletal structure. The reason people mimic animal structure is that animal has built adaptable nest to environment minimizing the waste of energy. In this aspect, various structures which are not revealed their functions could lead to potential design solutions. The habitat of Cleistostoma Dilatatum which is a kind of crab living in mudflat also has not been established. This paper describes a computational fluid dynamics (CFD) analysis results to investigate the ventilation effect of crab's habitat. Using a commercial code, ADINA Ver. 8.3, 2-D incompressible turbulence analyses are conducted for three cases.