• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제11권10호
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• pp.363-372
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• 2022

최근 코로나 19 팬더믹 이후 원격근무의 확대와 더불어 랜섬웨어 팬더믹이 심화하고 있다. 현재 안티바이러스 백신 업체들이 랜섬웨어에 대응하고자 노력하고 있지만, 기존의 파일 시그니처 기반 정적 분석은 패킹의 다양화, 난독화, 변종 혹은 신종 랜섬웨어의 등장 앞에 무력화될 수 있다. 이러한 랜섬웨어 탐지를 위한 다양한 연구가 진행되고 있으며, 시그니처 기반 정적 분석의 탐지 방법과 행위기반의 동적 분석을 이용한 탐지 연구가 현재 주된 연구유형이라고 볼 수 있다. 본 논문에서는 단일 분석만을 이용하여 탐지모델에 적용하는 것이 아닌 ".text Section" Opcode와 실제 사용하는 Native API의 빈도수를 추출하고 K-means Clustering 알고리즘, 코사인 유사도, 피어슨 상관계수를 이용하여 선정한 특징정보들 사이의 연관성을 분석하였다. 또한, 타 악성코드 유형 중 웜과 Cerber형 랜섬웨어를 분류, 탐지하는 실험을 통해, 선정한 특징정보가 특정 랜섬웨어(Cerber)를 탐지하는 데 특화된 정보임을 검증하였다. 위와 같은 검증을 통해 최종 선정된 특징정보들을 결합하여 기계학습에 적용하여, 최적화 이후 정확도 93.3% 등의 탐지율을 나타내었다.

• Journal of Plant Biotechnology
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• 제44권4호
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• pp.401-408
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• 2017

본 연구진은 세계 최초로 GFkV에 단독 감염된 포도 품종 거봉의 휴면아로부터 직접 경정 분열조직을 절취하여 배양함으로써 별도의 열처리나 화학처리 없이 GFkV가 제거된 신초 재생에 성공하였다. GFkV는 포도 식물체의 체관에만 한정적으로 존재하고 접목으로 감염되는 포도 바이러스이다. 경정조직은 $4^{\circ}C$에서 일정기간 저장된 1년생 경화가지의 휴면아로부터 0.3 mm (73 절편체)와 0.8 mm (5절편체)를 절취하였는데, 절취 부위는 생장점(apical meristem)을 포함하여 2 ~ 5개의 엽원기(leaf primordia)와 미분화 원기(uncommitted primordia) 1 ~ 4개를 포함하였다. 절취된 경정조직을 BA 3.0 mg/L와 IBA 0.1 mg/L가 혼합된 배지에 16주간 배양한 결과, 0.3 mm와 0.8 mm의 경정조직에서 각각 4.1%와 40.0%의 신초 재생률이 관찰되었고, 재생된 신초에서의 바이러스 제거율(재생된 신초수에 대한 RT-PCR negative 신초수의 백분율)은 0.3 mm의 경정조직에서는 100%를, 0.8 mm에서는 50%를 나타내었다. 신초를 증식시킨 후 감염바이러스를 다시 진단한 결과, 신초가 처음 재생되었을 때의 진단결과와 동일하였다. 휴면아로부터 분열조직을 배양하여 바이러스가 제거된 신초를 확보한 예는 세계적으로 보고된 바가 없는 것으로서, 본 연구진의 새로운 바이러스 제거방법은 향후 포도 뿐만 아니라 과수를 포함한 낙엽성 수목의 무병묘 생산에 매우 유용하게 활용될 수 있을 것이다.

• 한국작물학회지
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• 제67권4호
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• pp.253-264
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• 2022

본 연구는 콩 바이러스병 관리대책 수립을 위하여 생육 초기에 발생하는 바이러스병의 감염실태를 조사하였다. 국립식량과학원 육종포장에서 파종 후 약 3-4주 된 콩 이상증상 시료 83점을 채집하였다. 채집한 시료의 감염 바이러스 진단은 12종 바이러스의 RT-PCR 진단과 전체 시료에 대한 메타전사체 분석을 통하여 수행하였다. 1. 포장에서 바이러스병 발병율은 전체적으로 1% 미만으로 조사되었으며 일부 품종 및 라인에서는 최대 50%까지 나타내었다. 2. RT-PCR 진단과 메타전사체 분석 결과 SYMMV, SMV, SYCMV, PSV, SGVA가 검출되었다. 3. 검출된 바이러스 중에서 SYMMV와 SMV는 각각 검출율이 53.7%, 42.6%로 나타내어 콩 생육초기에 발생하는 주요 바이러스로 확인되었다. 4. SYMMV에 감염된 콩은 전형적인 모자이크 증상을 나타내었으며, SMV에 감염된 콩은 모자이크, 얼룩, 위축, 퇴록반점과 같이 다양한 증상을 나타내었다. 5. 바이러스 전염 특성을 고려할 때 SMV는 주로 종자전염을 통하여 발생한 것으로 판단되며, SYMMV는 종자전염과 함께 충매전염 및 토양전염의 가능성이 복합적으로 고려되어야 할 것으로 판단된다. 6. SGVA는 본 연구를 통하여 콩 생육초기 포장에서 검출되었으며, 생육초기 이후 발생실태 및 콩에 미치는 영향에 관한 연구가 신속히 수행되어야 할 것이다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권5호
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• pp.1919-1924
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• 2015

Polymorphisms in the region of the interleukin IL-28 gene on chromosome 19 have been related with clearance of hepatitis C virus (HCV), a major human pathogen responsible for chronic hepatitis, cirrhosis and hepatocellular carcinoma. About 3% of the world's population is infected with HCV. The long-term response to therapy is influenced by many host and viral factors, and recent evidence has indicated that some host genetic polymorphisms related to IL-28 are the most powerful predictors of virological response in patients with HCV. This study assessed frequency of the IL-28 polymorphism (rs8099917) in 50 patients (39 men and 11 women) with chronic hepatitis C using ZNA probe real time PCR new method. All patients were tested for genotype of HCV and the HCV viral load. In parallel, the levels of SGOT, SGPT and ALK enzymes were assessed. Treatment using Peg-interferon alpha with ribavirin was conducted for patients and subsequently samples were collected to detect any change in viral load or liver enzyme rates. The overall frequency of the TT allele is 74%, TG allele 20% and GG allele 6% and the percent of patients who had T allele was 84%. Clear reduction in viral load and liver enzymes was reported in patients with the T allele. Especially for genotype 1 which is relatively resistant to treatment, these alleles may have a role in this decline. In conclusion, we showed that IL-28 polymorphism rs8099917 strongly predicts virological response in HCV infection and that real-time PCR with Zip nucleic acid probes is a sensitive, specific and rapid detection method for detection of SNPs which will be essential for monitoring patients undergoing antiviral therapy.

• 한국동물위생학회지
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• 제32권3호
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• pp.177-187
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• 2009

The purpose of this study was to evaluate the effect of a subsequent infection of PCV2 on piglets with PEDV. The results obtained were as follows: Antibodies against PCV2 and PEDV were detected at 24, 36, 48, 60 and 72h postinfection. And the antibody titers of alone infections with PEDV were gradually reduced and increased from 60 hpi to 72 hpi. Whereas, the antibody titers of dual infections with PCV2 and PEDV were gradually reduced all the time. PEDV antigens were detected at 24, 36, 48, 60 and 72 hpi, being seen almost exclusively in feces and small intestines from PEDV-infected piglets and PCV2-coinfected piglets. The detection rate of PEDV in feces and jejunum tissues by RT-PCR were 94.9% and 91.1% in dual infections and 87.1% and 83.6% in alone infections with PEDV, respectively. In dual infected piglets, significantly more PEDV antigens were detected in the feces and small intestines tissues at 24 hpi (P<0.05) than in the same feces and tissues of the alone infected piglets. Thereafter, at 72 hpi significantly more PEDV antigens (P<0.05) was detected in the jejunal tissues of the dual infected piglets with than of alone PEDV-infected piglets. The detection rate of PEDV antigen in the duodenum, jejunum and ileum by IFA were 91.3%, 91.3% and 83.3% in dual infected piglets and 75.0%, 83% and 75% in alone infected piglets, respectively. Intense and specific fluorescence signals were more often seen within jejunal villous enterocytes in dual infected piglets than alone infected piglets.

• Asian Pacific Journal of Cancer Prevention
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• 제13권12호
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• pp.6109-6113
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• 2012

Background: Oral cancer has become one of the most prevalent cancers worldwide and human Papillomavirus is one of the risk factors for developing oral cancer. For this study HPV18 was chosen as it is one of the high risk HPV types and may lead to carcinogenesis. However, prevalence of HPV18 infection in Oral Squamous Cell Carcinoma in Malaysia remains unclear. Objective: This study aimed to investigate the viral load of HPV18 DNA in OSCC and potentially malignant lesions using saliva samples. Materials and Methods: Genomic DNAs of thirty saliva samples of normal subjects and thirty saliva samples compromised of 16 samples from potentially malignant lesions and 14 of OSCC patients were amplified for HPV18 DNA using a nested polymerase chain reaction analysis. All PCR products were then analyzed using the Bioanalyzer to confirm presence of HPV18 DNA. Result: From thirty patients examined, only one of 30 (3.3%) cases was found to be positive for HPV18 in this study. Conclusion: The finding of this study revealed that there is a low viral detection of HPV18 in Malaysian OSCC by using saliva samples, suggesting that prevalence of HPV18 may not be important in this group of Malaysian OSCC.

• Asian Pacific Journal of Cancer Prevention
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• 제13권4호
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• pp.1261-1266
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• 2012

Introduction: HPV has been found repeatedly in esophageal squamous cell carcinoma (ESCC) tissues. However, reported detection rates of HPV DNA in these tumors have varied markedly. Differences in detection methods, sample types, and geographic regions of sample origin have been suggested as potential causes of variation. We have reported that infection of HPV DNA in ESCC tumors depends on anatomical sites of esophagus of the patients from Mazandaran, north of Iran. Materials and Methods: HPV DNA was examined in 46 upper, 69 middle and 62 lower third anatomical sites of esophageal squamous cell carcinoma specimens collected from Mazandaran province in north Iran, near the Caspian Littoral as a region with high incidence of ESCC. HPV L1 DNA was detected using Qualitative Real time PCR and MY09/MY11 primers. Results: 28.3% of upper, 29% of middle and 25.8% of lower third of ESCC samples were positive for HPV DNA. 13.6% for males and 14.1% for females were HPV positive in all samples. Conclusions: HPV infection is about one third of ESCC in this area. Findings in this study increase the possibility that HPV is involved in esophageal carcinogenesis. Further investigation with a larger sample size is necessary.

• Asian Pacific Journal of Cancer Prevention
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• 제15권5호
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• pp.2245-2249
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• 2014

Background: Human papillomavirus is a well-established cause of the development of a variety of epithelial lesions in the cervix. However, as yet, incorporation of HPV testing into cervical cancer screening either as an adjunct or stand alone test is limited due to its cost. We therefore here ascertained the presence and type specificity of human papilloma virus (HPV) DNA in routine cervical scrapings. Materials and Methods: Cervical scrapings were collected from women attending clinics for routine Pap smear screening. HPV-DNA was detected by PCR using MY09/11 and GP5+/GP6+ primer sets and genotyping was accomplished by cycle-sequencing. Results: A total of 635 women were recruited into the study with $mean{\pm}SD$ age of $43{\pm}10.5$ years. Of these 92.6% (588/635) were reported as within normal limits (WNL) on cytology. The presence of HPV infection detected by nested MY/GP+-PCR was 4.4% (28/635). The overall prevalence of high-risk HPV (HR-HPV) in abnormal Pap smears was 53.8% (7/13). HPVs were also seen in 3.1% (18/588) of smears reported as WNL by cytology and 5.9% (2/34) in smears unsatisfactory for evaluation. Conclusions: The overall percentage of HPV positivity in routine cervical screening samples is comparable with abnormal findings in cytology. Conventional Pap smear 'missed' a few samples. Since HPV testing is expensive, our results may provide valuable information for strategising implementation of effective cervical cancer screening in a country with limited resources like Malaysia. If Pap smear coverage could be improved, HPV testing could be used as an adjunct method on cases with ambiguous diagnoses.

• 한국수산과학회지
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• 제45권6호
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• pp.666-674
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• 2012

We examined the cause of a disease outbreak in adult olive flounder Paralichthys olivaceus, which occurred at a Korean aquaculture farm in Korea in 2011. The principal signs included an expanded abdomen and congested liver, with persistent mortality (a little over two months). At the beginning of the outbreak, farm administrators misjudged the disease as bacterial in origin, because of the aforementioned signs, persistent mortality, and the detection of bacterial species, including Vibrio spp. and Streptococcus spp. Moreover, the detection of viral hemorrhagic septicemia virus (VHSV) by reverse trasnscription-PCR analysis was complicated by use of the VHS-VN primer set, which has been in general use recently, because it produced weak bands in some samples. Therefore, we recommend the use of at least two different primer sets in the diagnosis of VHSV. Our histopathological findings indicate that necrotizing myocarditis could be considered a pathogenic sign of VHSV infection.

• 한국수의병리학회지
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• 제6권1호
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• pp.19-26
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• 2002

The purpose of this study was to investigate to potective effects against porcine epidemic diarrhea virus (PEDV) infection in piglets by administration of the PEDV antiserum orally at 2 hrs, 24hrs and 36hrs after birth. six piglets administered the antiserum were experimentally infected with PEDV at five-day-old. Control group were four piglets infected with PEDV only. Serum antibody titers against PEDV were examined by serum neutralization (SN) test, dectection for PEDV or PEDV antigen from feces and small intestines was tested by reverse transcription-polymerase chain reaction (RT-PCR) and indirect immunoflurescence (IFA). The results obtained were as follows; 1. The piglets administered the PEDV antiserum showed higher antibody titers than those of control group and sustained during the experimental period. 2. The detection rate of PEDV in feces and small intestines by RT-PCR were 26.2% and 16.7% in PEDV antiserum treated group and 48.1 % and 75.0% in control group, respectively. 3. The detection rate of PEDV antigen in the small intestine by IFA were 0% in PEDV antiserum treated group and 50.0% in control group, respectively. It was concluded that oral administration of antiserum against PEDV to piglets was effective in preventing PEDV infection.