• 제목/요약/키워드: Detection agent

검색결과 465건 처리시간 0.025초

현장에서 초음파 파쇄와 형광시약을 이용한 단백질 독소의 조기 탐지 (The Early Detection of the Protein Toxin using Sanification and Fluorescent Dye in the Field)

  • 하연철;최기봉;김성주;최정도
    • KSBB Journal
    • /
    • 제22권1호
    • /
    • pp.48-52
    • /
    • 2007
  • 본 연구에서는 sonificator를 장착하여 세포막을 파쇄하고 현장에서 형광을 이용하여 조작이 간편하고 단시간에 DNA와 단백질을 동시에 측정할 수 있는 자동화된 형광기를 개발하기 위하여 단백질을 측정하는데 최적의 파쇄조건을 확립하고자 하였다. 용액 중에 녹아 있는 공기 중의 oxygen은 collisional quenching을 일으키는데 sonification이나 가열처리를 시키면 oxygen이 제거되어 quenching 효과가 크게 감소되어 높은 형광값을 나타내었다. 0.7 X 이상의 형광시약 농도에서는 반응시작 후 1분 이내에 측정해야 하며, 0.3 X 이하의 형광시약 농도에서는 반응시작 후 2$\sim$3분 사이에 반응을 시킨 후 측정하는 것이 바람직한 것으로 나타났다. $100{\mu}g/m{\ell}$ 이상의 BSA 농도에서는 형광시약이 포화되었으며, 시료를 sonification시키면 단백질이 변성되어 눈에 보일 정도로 불투명해져서 시료 용액의 불투명도로 인해 형광 값이 감소되는 경향을 나타내었으며, $1{\mu}g/m{\ell}$ 이하의 BSA 시료에서는 sonification을 시키지 않은 시료보다 sonification을 시켰을 때 $0.125{\mu}g/m{\ell}$의 BSA를 훨씬 더 구분이 잘 되어 낮은 단백질 농도에서는 sonification시키는 것이 훨씬 유리한 것으로 나타났다.

Seamless Lawful Interception Handover for 3G IP Multimedia Subsystem (IMS)

  • In, Hoh Peter;Lee, Myoung-Rak;Kim, Do-Hoon;Kim, Nung-Hoe;Yoon, Byung-Sik
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제5권7호
    • /
    • pp.1329-1345
    • /
    • 2011
  • After the 9.11 terror attack, lawful Interception (LI) has emerged as an important tool for anti-terrorist activity. Law enforcement agents and administrative government bodies effectively monitor suspicious target users of permanent IP-based network devices by LI in Packet Data Networks (PDNs). However, it is difficult to perform LI in monitoring migrating users from a location to another, who change their IPs due to the proliferation of portable Internet devices enabling 3G IP Multimedia Subsystems (IMS). The existing, manual handover technique in 3G IMS makes it even more difficult to continue the LI activities due to time-lag reissuance of LI authority warrants when the target users move to a new LI jurisdiction via a roaming service. Our proposed model is a seamless LI handover mechanism in 3G IMS to support mobility detection of the target users. The LI warrants are transferred to the new LI agent automatically with the target users when they move to a new LI jurisdiction. Thus, time-lag human intervention of reissuance of the LI warrants is removed and enables the LI authorities to continue monitoring. In the simulation of our proposed mechanism, the quality of lawful interception achieves a mean score of over 97.5% out of the possible 100% maximum score, whereas the quality of the existing mechanism has a mean score of 22.725%.

식품병마개 PVC gasket과 식품에 함유된 semicarbazide의 분석 (Determination of Semicarbazide in PVC Gaskets of Food Bottle Cap and Foods)

  • 박상욱;이광호;곽인신;전대훈;이시경
    • 한국식품과학회지
    • /
    • 제37권3호
    • /
    • pp.334-338
    • /
    • 2005
  • 본 연구는 식품병마개 PVC 가스켓과 식품에 함유된 SEM을 효과적으로 분석하기 위해 연구했다. SEM은 발포제로 사용되는 ADC의 열분해산물로 알려졌다. 그러나 SEM은 분자량이 낮으며 ultraviolet light나 fluorescence에 활성을 갖지 않는다. 따라서 2-NBA-SEM으로 유도체화하여 HPLC triple column system으로 분석했을 때 상관관계는 0.9997이상이며 검출한계는 0.48ng/g으로 나타났다. 식품병마개 PVC 가스켓에서 SEM의 검출율은 77.08%로 나타났으며, 유통중인 병마개 PVC 가스켓에서 SEM은 812.20-5771.30ng/g 수준이였다. 그리고 회수율은 PVC 가스켓과 식품에서 각각 92.12-98.71%와 83.45-97.33%로 측정되었다.

A Waterborne Outbreak and Detection of Cryptosporidium Oocysts in Drinking Water of an Older High-Rise Apartment Complex in Seoul

  • Cho, Eun-Joo;Yang, Jin-Young;Lee, Eun-Sook;Kim, Se-Chul;Cha, So-Yang;Kim, Sung-Tek;Lee, Man-Ho;Han, Sun-Hee;Park, Young-Sang
    • Parasites, Hosts and Diseases
    • /
    • 제51권4호
    • /
    • pp.461-466
    • /
    • 2013
  • From May to June 2012, a waterborne outbreak of 124 cases of cryptosporidiosis occurred in the plumbing system of an older high-rise apartment complex in Seoul, Republic of Korea. The residents of this apartment complex had symptoms of watery diarrhea and vomiting. Tap water samples in the apartment complex and its adjacent buildings were collected and tested for 57 parameters under the Korean Drinking Water Standards and for additional 11 microbiological parameters. The microbiological parameters included total colony counts, Clostridium perfringens, Enterococcus, fecal streptococcus, Salmonella, Shigella, Pseudomonas aeruginosa, Cryptosporidium oocysts, Giardia cysts, total culturable virus, and Norovirus. While the tap water samples of the adjacent buildings complied with the Korean Drinking Water Standards for all parameters, fecal bacteria and Cryptosporidium oocysts were detected in the tap water samples of the outbreak apartment complex. It turned out that the agent of the disease was Cryptosporidium parvum. The drinking water was polluted with sewage from a septic tank in the apartment complex. To remove C. parvum oocysts, we conducted physical processes of cleaning the water storage tanks, flushing the indoor pipes, and replacing old pipes with new ones. Finally we restored the clean drinking water to the apartment complex after identification of no oocysts.

Seroprevalence of Toxoplasma gondii among HIV Patients in Jahrom, Southern Iran

  • Rezanezhad, Hassan;Sayadi, Fateme;Shadmand, Enayatollah;Nasab, Seyed Dawood Mousavi;Yazdi, Hadi Rezaei;Solhjoo, Kavous;Kazemi, Akbar;Maleki, Monireh;Vasmehjani, Abbas Ahmadi
    • Parasites, Hosts and Diseases
    • /
    • 제55권1호
    • /
    • pp.99-103
    • /
    • 2017
  • Toxoplasma gondii is an important opportunistic agent especially in immunocompromised hosts and can cause significant morbidity and mortality. Hence, detection and monitoring of anti-Toxoplasma antibodies are of a great interest in HIV-infected patients. A study on the prevalence of toxoplasmosis and associated risk factors was carried out among HIV-infected patients in Jahrom, southern Iran. The prevalence of anti-Toxoplasma IgG antibodies was 21.1% in HIV-infected patients by ELISA. PCR was performed on all of the samples, and 1 of the blood samples was positively detected. Among the HIV patients, anti-Toxoplasma IgG antibodies were significantly higher in age group of 30-39 years old (P=0.05). The seroprevalence of toxoplasmosis in patients with $CD4^+$ < $100cells/{\mu}l$ was 33.3% that was significantly higher than the other groups (P=0.042) with or without IgG antibodies. The $CD4^+$ count mean of seropositive patients was lower than that of seronegative patients. The seroprevalence of toxoplasmosis in patients with highly active antiretroviral therapy was significantly less than patients without therapy (P=0.02). In conclusion, this study showed low seroprevalence of latent toxoplasmosis among HIV-infected patients in the region and confirmed the need for intensifying prevention efforts among this high-risk population and also the risk of toxoplasmosis reactivation which could be important among this population.

HG-ICP-AES를 이용한 Germanium 분석에 있어서 보조산에 대한 연구 (Investigation of Acids on the Germanium Analysis by HG-ICP-AES)

  • 임현의;이연희;김선태;김영상;김강진
    • 분석과학
    • /
    • 제14권1호
    • /
    • pp.34-43
    • /
    • 2001
  • 수소화물생성법-유도결합플라스마-원자방출분광법으로 게르마늄을 분석할 때 보조산으로 phosphoric acid의 사용은 nitric acid, hydrochloric acid, sulfuric acid, perchloric acid, boric acid, tartaric acid, malic acid, oxalic acid, acetic acid, tannic acid, citric acid의 사용보다 높은 수소화물 생성효율을 보였고, 같은 pH영역이라도 phosphate ion이 존재하는 buffer의 사용이 더 높은 생성효율을 보였다. 또한, 2.5M phosphoric acid를 이용한 결과, 시료용액 내에 잔류하는 산이나 공존원소의 영향이 감소하였다. 환원제와 안정제의 농도가 증가할수록 수소화물 생성효율은 증가되었으며, 최대방출세기를 나타내는 산의 세기는 높은 쪽으로 이동했고 농도영역은 넓어졌다. 인산 존재 하에서의 게르마늄의 검출한계는 $0.03{\mu}g/L$이었다.

  • PDF

FAAS를 이용한 혈중 Cisplatin의 분석법 개발 (The Development of Cisplatin Analysis Method in Plasma by Flameless Atomic Absorption Spectrometry)

  • 백만정;임호섭;정미진;이경옥;신호상
    • 분석과학
    • /
    • 제11권4호
    • /
    • pp.243-247
    • /
    • 1998
  • 백금을 함유한 항암제로 신장과 신경계에 심각한 부작용을 일으키는 cisplatin의 혈중 농도를 flameless atomic absorption spectrometry법(FAAS)으로 분석하였다. 이 방법은 시료전처리 과정이 필요 없어 신속하고 간단한 분석법이다. 검정곡선에 대한 직선성을 조사한 결과 20~1000ng/mL 농도 범위에서 r=0.999로 나타났으며, 정확도는 50 ng/mL 이상의 농도에서 상대표준편차가 5.0% 이하 이었다. 그리고, 혈장시료 $200{\mu}L$에 대한 검출한계는 10 ng/mL 이었다. 본 방법은 cisplatin의 최적 치료 조건과 독성 경감을 위한 혈중 모니터링에 그 활용이 크게 기대된다.

  • PDF

Knowledge, Attitudes and Practices of Sudanese Women Regarding the Pap Smear Test and Cervical Cancer

  • Almobarak, Ahmed O;Elbadawi, Ayman A;Elmadhoun, Wadie M;Elhoweris, Mohammed H;Ahmed, Mohammed H
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제17권2호
    • /
    • pp.625-630
    • /
    • 2016
  • Background: Despite the established role of the Pap smear test (PST) in prevention and early detection of cervical cancer, it is still rarely practiced in Sudan. Many challenges hinder the establishment of an effective cervical cancer screening program, including socio-cultural factors. Therefore, this study aimed to investigate the knowledge, attitudes and practices (KAP) of Sudanese women with regard to the Pap smear test and cervical cancer. Materials and Methods: A total of 500 married women aged 14 to 58 years were recruited from obstetric clinics, hospitals and universities in Khartoum in 2014. Data were collected using a standardized, pretested questionnaire that inquired socio-demographic characteristics and their KAP about cervical cancer and the PST. Results: More than 52% of participating women were above 30 years of age, and the majority (78.8%) were university degree holders. A total of 486 (97.2 %) of participants were resident in urban areas of Khartoum State. However about 48% of the respondents had never heard about PST, and only 15.8% of the participants had undergone a Pap smear test previously; 46.6% (233/500) knew that the human papilloma virus (HPV) was the causative agent, but only 39.2% (196/500) had heard about HPV vaccination, and only 11.4% (57/500) had received the vaccine. However 68% of the respondents agreed to do Pap smear if properly informed about the test and 75.4% of the respondents agreed to participate in a cervical cancer screening program. Conclusions: Despite a high educational level, less than half of our participants had accurate knowledge about cervical cancer, HPV, and cervical cancer screening. Health education about cervical cancer, HPV and sexually transmitted infections and the role of PST in cervical cancer prevention are crucial when designing interventions aimed at improving cervical cancer screening for Sudanese women.

목련잎 추출액을 이용한 Au Core-Ag Shell 합금 나노입자의 생물학적 합성 (Biological Synthesis of Au Core-Ag Shell Bimetallic Nanoparticles Using Magnolia kobus Leaf Extract)

  • 송재용;김범수
    • Korean Chemical Engineering Research
    • /
    • 제48권1호
    • /
    • pp.98-102
    • /
    • 2010
  • 목련잎 추출액을 이용하여 Au core-Ag shell 합금 나노입자를 합성하였다. 환원제인 식물잎 추출액을 먼저 $HAuCl_4$ 용액과 반응시키고 다음에 $AgNO_3$ 용액과 반응시켜 금 seed와 은 shell을 형성시켰다. 반응시간에 따른 UV-visible spectroscopy의 변화를 모니터링하여 합금 나노입자의 형성을 관찰하였다. 합성된 합금 나노입자를 transmission electron microscopy(TEM), energy dispersive X-ray spectroscopy(EDS), X-ray photoelectron spectroscopy(XPS) 등으로 특성화 하였다. TEM image로부터 관찰된 합금 나노입자는 삼각형, 오각형, 육각형 등의 평판과 구 구조의 혼합물이었다. EDS와 XPS 분석으로부터 결정된 금/은 합금 나노입자의 원자 은 함량은 각각 34와 65 wt%로 Au core-Ag shell 나노구조가 형성되었음을 알 수 있었다. 이러한 core-shell 형태의 나노구조는 표면 강화 라만 분광 및 생물분자의 고감도 검출 등에 잠재적인 응용이 기대된다.

급성위장관염 환자에서 검출된 노로 바이러스 Genogroup-I과 Genogroup-II의 분자생물학적 특성 (Molecular Characteristics of Human Noroviruses Genogroup I and Genogroup II Detected in Acute Gastroenteritis Patients in Seoul)

  • 함희진;오세아;김창규;장정임;조석주;최성민
    • 한국환경보건학회지
    • /
    • 제38권1호
    • /
    • pp.57-65
    • /
    • 2012
  • Objectives: For our survey of the incidence of norovirus infections and the genogroup distribution of norovirus in Seoul, Republic of Korea, we evaluated through regular surveillance the prevalence of norovirus infections in patients with acute gastroenteritis occurring in Seoul from January 2007 to July 2011. Methods: For norovirus detection, we conducted epidemiological analyses on the basis of the junction of ORF1 and ORF2 (approximately 314 bp). 11,202 fecal specimens were collected from patients in Seoul with acute gastroenteritis between January 2007 and July 2011 and then tested for the presence of NoV via reverse transcription (RT) - polymerase chain reaction (PCR). Results: 16.6% (1,861/11,202) of the fecal specimens were determined to be positive for noroviruses. The incidences of norovirus infection in Seoul in the case of acute gastroenteritis with regular surveillance were 28.0% in 2007, 14.6% in 2008, 9.1% in 2009, 14.1% in 2010, and 12.9% in 2011, which shows that noroviruses constituted a major causative agent of acute gastroenteritis. Also, the incidence of noroviral infection in patients with acute gastroenteritis increased after the large-scale new influenza in 2009. Conclusions: The genetic characteristics of norovirus and the epidemiologic patterns of a viral pathogen in acute gastroenteritis patients may provide potentially effective data for epidemiological studies in Seoul, Korea.