Earticle

For the effective identification of drug-toxicants as the cause of death in forensic toxicology, it is important to analyze and establish the recent patterns of detected drugs in postmortem specimens and share their informations. So, we evaluated the results of the identification and their patterns of drug-toxicants detected in autopsy cases which occurred in Metropolitan areas including Seoul, Incheon and Gyeonggi province, and conducted by main office of National Forensic Service (NFS) during last three years (2010~2012). The results of requested cases in last three year, indicate that the frequencies of requests are 43.7 %, 43 % and 27 % from Gyeonggi, Seoul, and Incheon province, respectively. Men are more common than women, and positive results are less than negative results. As the detection rates of drug-toxicants, drugs, cyanide and pesticides are 93.27 %, 3.95 %, and 2.51 %, respectively. Most frequently detected drugs are chlorpheniramine (antihistamine), lidocaine(local anesthetics and antiarrhythmics) and atropine (parasympatholytics), which are supposed to be used for the emergent therapeutic purpose such as cardiac resuscitation in hospitals. Among pesticides, paraquat, methomyl, glyphosate, methidathion are highly detected in the order of frequency. These statistical analyses of drug-toxicants in postmortem specimens will be very helpful for prediction of causes of deaths in postmortem specimens.

A case report involving a 16-years-old woman who was found dead by her brother in the room is presented. At the time of her death, she was being treated with propranolol, fluoxetine, doxepin, alprazolam, amitriptyline, and lorazepam. Her family stated that she had been prescribed two weeks of medicine at the hospital the day before she died, and there were 42 empty paper envelopes on the desk. The manner of death was not founded in autopsy, and femoral venous blood, cardiac blood, and stomach contents were collected and analyzed. Propranolol, fluoxetine, doxepin, alprazolam, amitriptyline, nortriptyline, and lorazepam were detected in autopsy specimens. Protein precipitation was adopted in sample preparation, and liquid chromatography/tandem mass spectrometry (LC/MS/MS) was used for identification and quantification. The concentrations of propranolol (5.56 mg/L), fluoxetine (5.10 mg/L), doxepin (0.27 mg/L), and alprazolam (0.11 mg/L) detected in femoral venous blood were within the toxic or lethal range, and amitriptyline (0.45 mg/L) and lorazepam (0.13 mg/L) were in therapeutic range. Based on these results, combined drug intoxication resulting in synergistic effect on organ dysfunction and central nervous system depression has been proposed as the cause of death. This case can be considered as a good reference when examining the correlation between postmortem blood concentrations and doses.

A liquid nitrogen-cooled prepolarization (Bp) coil made for ultra-low field nuclear magnetic resonance and magnetic resonance imaging (ULF-MR) designed to generate 7 mT/A was fabricated. However, with suspected internal insulation failure, the coil was investigated in order to find out the source of the failure. This paper reports detailed build of the failed Bp coil and a number of analysis methods utilized to figure out the source and the mode of failure. The analysis revealed that pyrolytic graphite sheet linings put on either sides of the coil for better thermal conduction acted as an electrical bridge between inner and outer layers of the coil to short out the coil whenever a moderately high voltage was applied across the coil. A simple model circuit simulation corroborated the analysis and further revealed that the failed insulation acted effectively as a damping resistor of Rd,eff = 6 Ω across the coil. This damping resistance produced a 50 ms-long voltage tail after the coil current was ramped down, making the coil not suitable for use in ULF-MR, which requires complete removal of magnetic field from Bp coil within milliseconds.

도축 후 돈육의 육질평가에 있어 중요한 요인인 사후 24시간 pH를 측정하여 pH가 5.31∼5.50, 5.51∼5.70, ≥5.71에 따른 육질을 조사한 결과, 사후 pH가 더 낮을수록 단백질 함량이 높고, 지방 함량이 낮았다(P<0.05). 사후 24시간 pH가 높을수록 보수력은 증가하였으며, 가열감량과 육즙감량은 유의적으로(P<0.05) 감소하였다. 육의 경도, 탄력성, 씹힘성과 지방경도 역시 사후 24시간 pH가 높을수록 유의적인 증가를 보였다(P<0.05). 육색특성 중 CIE L*값은 사후 24시간 pH가 낮을수록 유의적으로 높았으며, a*와 b*값, chroma 값은 최종 pH가 5.71 이상의 돈육에서 유의적으로 낮게 나타났다(P<0.05). Hue 값은 pH 5.31∼5.70 범위에서 가장 높았으며, ΔE 값도 pH 5.31∼5.50에서 가장 높았다. 관능적 특성의 분석결과, 다즙성과 연도는 최종 pH가 높을수록 향상되었으나, 향미는 최종 pH 범위에 따른 차이가 인정되지 않았다. 따라서 본 연구결과, 도축 후 24시간 돈육의 pH 범위에 따라 육질의 차이를 보이기 때문에 사후 적정 pH를 유지할 수 있도록 도축전 관리, 도축방법, 도축 후 냉각 온도관리 등을 개선하는 것이 고품질 돈육생산에 있어 중요한 것으로 사료된다.

Meat quality of the domestic pork loins(n=537) classified by 3 groups(5.31∼5.50, 5.51∼5.70 and ≥5.71) according to pH at 24hr post-mortem(pH24) was investigated. In proximate chemical compositions, protein was highest and fat was lowest in the pork loins of pH24 5.31∼5.50 group. Water holding capacity increased as pH24 increased, whereas purge loss and cooking loss decreased as pH24 increased. Meat color values(CIE L*, a*, b*, Chroma, Hue and ΔE) decreased as pH24 increased. In texture traits, hardness and chewiness were lowest and fat hardness was highest in the pork loins of pH24≥5.71 group when compared to the other pH24 groups. However, Warner-Bratzler Shear force, springiness and cohesiveness were not significantly different among the pH24 groups(P>0.05). In sensory properties, juiciness and tenderness were highest in pH24≥5.71 group. From the results of this study, pork quality was highly related to pH24. Therefore, the factors affecting the post-mortem pH, such as stress before slaughter, slaughtering methods, and cooling condition slaughter must be properly controlled and improved to produce high quality pork.

곤충들은 주변 환경에 따라 일정한 성장 속도를 가지고 있으며, 사체와 관련된 다양한 특징을 지니고 있어 사후경과시간(PMI, Postmortem of Interval) 추정에 좋은 방법이 될 수 있다. 구더기의 성장 속도 및 유효적산온도(ADH, accumulated degree of hour)를 이용하여 PMI를 추정하기 위하여 충청남도 아산시 순천향대학교 본교 내 야산의 양지에서 2012년 9월 20일부터 10월 5일까지 돼지 부패 실험을 실시하였다. 9월 26일 17시 돼지사체에서 3령의 구더기를 채집(사체와 지면사이)하고 사육하기 시작하여 70시간이 경과한 9월 29일 15시경에 사육 통에서 용화된 2마리의 번데기를 확인하였고, 10월 4일 14시경부터 성충으로 우화되기 시작한 파리는 검정뺨금파리(Chrysomyia megacephala)로 동정(identification)되었다. 현장에서 구더기를 채집한 9월 26일 17시 이전의 대기온도를 추정하기 위하여 9일 동안의 기상청의 시간 별 평균 대기온도 값을 독립변수, 현장의 간이기상대의 시간 별 평균 대기온도 값을 종속변수로 설정하여 단순회귀분석을 실시하였으며, 현장 평균대기온도는 기상청의 평균대기온도보다 통계학적으로 0.7℃ 낮은 것으로 추정되었다(상관계수 r=0.9977). 한 편, 구더기의 먹이 활동으로 인한 마찰열로 인하여 구더기 군집의 중심부 온도가 대기온도 보다 상승하게 되는 효과(maggots mass of effect)를 감안하기 위하여, 3령 기간 동안 필요한 ADH값(1426.32 ADH), 채집시의 구더기 군집의 중심부 온도와 대기온도의 차(9.77℃), 현장에서 3령으로 존재하였을 것으로 추정된 시간(29,51hr)을 이용하여 계산한 결과, 추가하여야 할 ADH값은 288.31 ADH(29,51hr x 9,77℃)로 계산되었다. 또한, 검정뺨금파리의 성장이 정지되기 시작하는 발육한계저온도(Base Temperature)는 12℃, 알에서 번데기까지 발생하기 위하여 필요한 유효적산온도값은 1656 ADH, 알에서 성충까지는 3408 ADH로 외국의 문헌에서 조사되었다. 위의 실험 결과들 및 문헌 조사결과를 이용하여 3령의 구더기를 채집한 시간으로부터 유효적산온도 값을 역으로 계산하고 구더기 군집에 의한 온도상승효과를 감안하기 위하여 ADH값을 추가하여 계산한 결과, 파리에 의해 최초 산란이 이루어진 것으로 추정되는 시간인 9월 20일 22시 이전에 사망한 것으로 추정되어 실제 사망시간(9월 20일 12시)과 10시간의 오차가 발생하였다. 본 실험을 통해 부패된 시체에서 PMI를 추정할 수 있다는 것을 확인했다는 점에서 고무적이었으나 여전히 작지 않은 시간상 오차가 존재하므로 오차의 원인을 밝혀내고 이것을 통제하기 위해서 추가적으로 많은 실험이 필요할 것으로 판단된다.

Insects have certain life cycle depending on surrounding environments, and their unique features of growth can be effective for estimation of PMI (postmortem interval). In this study, to estimate PMI through measuring growth speed of maggots and ADH (accumulated degree of hour), this decomposition experiment on a pig was conducted in campus of Soonchunhyang University, Asan, Choongchungnamdo. We calculated PMI statistically on the basis of temperature changes collected by a movable meteorological observatory and a probe-mounted temperature recorder. In addition, we observed and documented growth speed of maggots. In conclusion, it is very significant that PMI can be traced through life cycle of flies, although the errors between intervals were also found.