• Title/Summary/Keyword: PAIR

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Changing Gadolinium-Based Contrast Agents to Prevent Recurrent Acute Adverse Drug Reactions: 6-Year Cohort Study Using Propensity Score Matching

  • Min Woo Han;Chong Hyun Suh;Pyeong Hwa Kim;Seonok Kim;Ah Young Kim;Kyung-Hyun Do;Jeong Hyun Lee;Dong-Il Gwon;Ah Young Jung;Choong Wook Lee
    • Korean Journal of Radiology
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    • v.25 no.9
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    • pp.824-832
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    • 2024
  • Objective: To determine the preventive effect of changing gadolinium-based contrast agents (GBCAs) to reduce the recurrence of GBCA-associated acute adverse drug reactions (ADRs). Materials and Methods: This retrospective, observational, single-center study-conducted between January 2016 and December 2021-included 238743 consecutive GBCA-enhanced MRI examinations. We focused on a subgroup of patients who experienced acute GBCA-associated ADRs during any of these examinations and subsequently underwent follow-up GBCA-enhanced MRI examinations up until July 2023. The follow-up examinations involved either the same (non-change group) or different (change group) GBCAs compared to the ones that initially caused the acute ADR. Baseline participant characteristics, generic profile of the GBCAs, administration of premedication, history of prior ADR to iodinated contrast media, and symptoms of GBCA-associated acute ADRs were retrospectively analyzed. Multivariable logistic regression with generalized estimating equations and propensity score matching were used. Results: A total of 1042 instances of acute ADRs (0.44%; 95% confidence interval [CI]: 0.41%-0.46%) were reported. Three-hundred and seventy-three patients underwent GBCA-enhanced MRI examinations after experiencing GBCA-associated acute ADRs within the study period; 31.9% (119/373) reexperienced acute ADRs at any of the follow-up examinations. The ADR recurrence was significantly lower in the GBCA change group than in the non-change group according to multivariable logistic regression (adjusted odds ratio [OR]: 0.35; 95% CI: 0.13-0.90; P = 0.03) and analysis with propensity score matching (14.3% [6/42] vs. 36.9% [31/84], respectively; OR: 0.32, 95% CI: 0.11-0.94; P = 0.04). A history of an ADR to iodinated contrast media (OR: 1.14, 95% CI: 0.68-1.90; P = 0.62) and premedication (adjusted OR: 2.09, 95% CI: 0.93-4.68; P = 0.07) were not significantly associated with GBCA-associated acute ADR recurrence. A separate analysis for recurrent allergic-like hypersensitivity reactions demonstrated similar results (adjusted OR: 0.20, 95% CI: 0.06-0.65; P < 0.01). Conclusion: Changing GBCAs may reduce the risk of GBCA-associated acute ADR recurrence.

Enhancing Conventional PCR for Detection of Erwinia amylovora (화상병원세균 검출을 위한 Conventional PCR 향상)

  • Hyun Ju Choi;Yeon Ju Kim;Jeong Ho Choi;Dong Hyuk Choi;Duck Hwan Park
    • Research in Plant Disease
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    • v.30 no.3
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    • pp.294-299
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    • 2024
  • Polymerase chain reaction (PCR) methods, including conventional PCR (cPCR) and quantitative real-time PCR (qRT-PCR), with both plasmid- and chromosome-targeting primers, are currently the most reliable methods for detecting Erwinia amylovora due to their high sensitivity and specificity. Despite qRT-PCR's quantitative advantage, cPCR remains an attractive method to detect this bacterium in initial screenings of suspected host plants, as it is cost-effective and does not require skilled personnel in well-equipped laboratories. This study aimed to significantly improve cPCR robustness via application of bovine serum albumin (BSA) as a PCR facilitator, with a modified EaF/R primer pair, as previously reported. Experiments have shown that simple supplementation with BSA (10 mg/ml) enhances cPCR reactions using templates such as genomic DNA, bacterial cells, and infected symptomless host organs, including immature apple fruits and seedlings, with EaF/R primers. The cPCR method described in this study is simple, specific, and reliable, and can be applied in routine assays to diagnose fire blight.

Analysis of Microbial Communities of Salted Cabbage and Kimchi according to Cultivation Areas (재배지역에 따른 절임배추 및 김치의 미생물 군집 분석)

  • Chang Eun Kim;Soo Hyun Kim;Min Seo Jung;Seung Lim Lee
    • Microbiology and Biotechnology Letters
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    • v.52 no.3
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    • pp.304-313
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    • 2024
  • In this study, the microbial distribution and diversity of kimchi manufactured in the same method as salted cabbage manufactured from Pyeongchang, Andong, and Haenam cabbage according to the storage period were compared. Among Pyeongchang, Andong, and Haenam salted cabbages, the Haenam salted cabbage microbial community showed the highest diversity on the 1st day of storage. As the storage period of salted cabbage increased, the alpha diversity value increased, the proportion of cyanobacteria decreased, and bacteria derived from sea salt and water increased. Principal coordinates analysis(PCoA) and unweighted pair group method with arithmetic mean(UPGMA) trees showed that Andong salted cabbage on the 5th day of storage had a microbial community close to salted cabbage on the 10th day of storage. At the species level, Sinocapsa zengkensis was 78.65%, 90.64%, and 63.44%, respectively, in Pyeongchang, Andong, and Haenam salted cabbages on the 1st day of storage. Marinomonas primoryensis was showed in Pyeongchang, Andong, and Haenam salted cabbage on the 5th day of storage at 24.39%, 26.60%, and 21.75%, respectively, and at 42.17%, 31.43%, and 45.21%, respectively, on the 10th day of storage. Kimchi made from Pyeongchang, Andong, and Haenam salted cabbages showed Janthinobacterium lividum at 30.47%, 29.60%, and 25.97%, respectively. In addition, Leuconostoc spp. involved in fermentation were showed from the 5th day of storage, but Andong salted cabbage on the 10th day of storage was not showed. These results show to be due to differences in soil, climate, and cultivation methods of cabbage.

Studies on the Inheritance of Heading Date in Wheat(Triticum aestivum L. em Thell) (소맥(Triticum aestivum L. em Thell)의 출수기 유전에 관한 연구)

  • Chang-Hwan Cho
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.15
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    • pp.1-31
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    • 1974
  • Introducing genes for earliness of wheat varieties is important to develop early varieties in winter wheat. In oder to obtain basic informations on the response of heading to the different day length and temperature treatments and on the inheritance of heading dates, experiments were conducted at the field and greenhouse of the Crop Experiment Station, Suwon. Varieties used in this experiments were, early variety Yecora F70, medium varieties Suke #169, Parker and Yukseung #3, and late varieties Changkwang, Bezostaia, Sturdy and Blueboy. The parents and F$_1$s of partial diallel crosses of above eight varieties were subjected the following four different treatments; 1. high temperature and long day, 2. high temperature and short day, 3. low temperature and long day, and 4. low temperature and short day. The same materials were grown also in field condition. Parents, F$_1$ and F$_2$ generation were grown also in both greenhouse under high temperature and short day and in field. The results obtained were summarized as follow: 1. No effects of temperature and daylength on the number of leaves on the main stem were found when -varieties were vernalized. The number of main stem leaves were fewer for spring type of varieties than for winter type of varieties. 2. The effects of temperature and daylength on the days to flag leaf opening were dependent on the speed of leaf emergence. The speed of leaf emergence were faster for lower leaves than for upper leaves. 3. The response to short day and long day (earliness of narrow sense) of varieties were found to be direct factor responsible to physiology of heading dates in vernalized varieties. Great difference of varieties to heading date was found in high temperature and short day treatment, but less differences were found in high temperature and long day, low temperature and long day and low temperature and short day treatments respectively. The least varietal difference for heading dates was found in the field condition. 4. Changkwang and Parker were found to be the most sensitive to short day treatment (photosensitive) and the heading of these varieties were delayed by short day treatment. No great varietal differences were found among other varieties. 5. Varietal differences of heading dates due to daylength were greater in high temperature than in low temperature. 6. Varietal differences of heading dates due to temperature were not great. but in general the heading dates of varieties were faster under high temperature than under low temperature. 7. Earliness of heading dates was due to partial dominance effect of genes involved in any condition. The degree of dominance was greater under short day than under long day treatment. 8. The varietal differences of heading date under high temperature and long day were due to earliness or narrow sense (response to long day) of varieties. The degree of dominance was greater for Yecora F70, spring type than for other winter type of varieties. No differences or less differences of degree of dominance was found among winter type of varieties. The estimated number of effective factor concerned in the earliness of narrow sense was one pair of allele with minor genes. 9. The insensitivity of varieties to short day treatment in heading dates was due to single dominant gene effect. Under the low temperature the sensitivity of varieties to short day treatment was less apparent. 10. The earliness of short day and long day (earliness of narrow sense) sensitivities of varieties appearea to be due to partial dominance of earliness over lateness. In strict sense, the degree of the dominance should be distinguished. 11. Dominant gene effects were found for the thermo-sensitivity of varieties, and the effect was less, significant than the earliness in narrow sense. 12. One pair of allele, ee and EE, for photosensitivity was responsible for the difference in the heading dates between Changkwang and Suke #169. Two pairs of alleles, ee, enen and EE, EnEn. appeared to be responsible for the difference between Changkwang and Yecora F70. The effects of EE and EnEn were, additive to the earliness and the effects of EE were greater than EnEn under short day. However, the effects of EE were not evident in long day but the effects of EnEn were observed in long day. 13. Two pairs of dominant alleles for the earliness were estimated from the analysis of F$_1$ diallels in the field but the effects of these alleles in F$_2$ were not apparent due to low temperature and short day treatment in early part of growth and high temperature and long day treatment in later part of growth. The F$_2$ population shows continuous variation due to environmental effects and due to other minor gene effects. 14. The heritabilities for heading dates were ranged from 0.51 to 0.72, indicating that the selection in early generation might be effective. The extent of heritability for heading dates varied with environments; higher magnitude of heritability was obtained in short day treatment and high temperature compared with long day and low temperature treatments. The heritabilities of heading date due to response to short day were 0.86 in high temperature and 0.76 in low temperature. The heritabilities of heading date due to temperature were not significantly high. 15. The correlation coefficients of heading dates to the number of grains per spike, weight of 1, 000 grains. and grain yield were positive and high, indicating the difficulties of selections of high yielding lines from early population. But no significant correlation coefficient was obtained between the earliness and the number of spikes, indicating the effective selection for high tillering from early varieties for high yielding.

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A Study on the Excavated Sab(a funeral fan) from Lime-filled Tomb and Lime-layered Tomb during the Joseon Dynasty (조선시대 회격·회곽묘 출토 삽(翣)에 대한 고찰)

  • Yi, Seung Hae;An, Bo Yeon
    • Korean Journal of Heritage: History & Science
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    • v.41 no.2
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    • pp.43-59
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    • 2008
  • Sap(?, a funeral fan) is a funeral ceremonial object used in association with a Confucian ceremonial custom, which was crafted by making a wooden frame, attaching a white cloth or a thick paper onto it, drawing pictures on it, and making a holder for a handle. According to Liji(Records of Rites), Sap was used since the Zhou Dynasty, and these Chinese Sap examples are no big different than the Korean Sap examples, which were described in Joseon Wangjo Sillok(Annals of the Joseon Dynasty), Gukjo Oryeui(the Five Rites of the State), and Sarye Pyeollam(Handbook on Four Rituals). This study explored Sap excavated in lime-filled tombs and lime-layered tombs of aristocrats dating back to Joseon, as well as their historical records to examine Sap's characteristics according to their examples, manufacturing methods, and use time. The number and designs of Sap varied according to the deceased' social status aristocrats used mainly one pair of 亞-shaped Bulsap, and a pair of Hwasap with a cloud design depicted on it. A Sap was wrapped twice with Chojuji paper or Jeojuji paper, and for the third time with Yeonchangji paper. Then, it was covered with a white ramie, a hemp, a cotton, a silk satin, etc. Bobul(an axe shape and 亞-shape design) was drawn on both sides of Sap, and a rising current of cloud was drawn at the peripheral area mainly with red or scarlet pigments. Sap, which were excavated from aristocrats'lime-filled and lime-layered tombs, are the type of Sap which were separated from its handle. These excavated Sap are those whose long handles were burnt during the death carriage procession, leaving Sap, which later were erected on both sides of the coffin. The manufacturing process of excavated relics can be inferred by examining them. The excavated relics are classified into those with three points and those with two points according to the number of point. Of the three-point type(Type I), there is the kind of relic that was woven into something like a basket by using a whole wood plate or cutting bamboo into flat shapes. The three-point Sap was concentrated comparatively in the early half of Joseon, and was manufactured with various methods compared with its rather unified overall shape. In the meantime, the two-point Sap was manufactured with a relatively formatted method; its body was manufactured in the form of a rectangle or a reverse trapezoid, and then its upper parts with two points hanging from them were connected, and the top surface was made into a curve(Type II) or a straight line(Type III) differentiating it from the three-point type. This manufacturing method, compared with that of the three-point type, is simple, but is not greatly different from the three-point type manufacturing method. In particular, the method of crafting the top surface into a straight line has been used until today. Of the examined 30 Sap examples, those whose production years were made known from the buried persons'death years inscribed on the tomb stones, were reexamined, indicating that type I was concentrated in the first half of the $16^{th}$ century. Type II spanned from the second half of the $16^{th}$ century to the second half of the $17^{th}$ century, and type III spanned from the first half of the $17^{th}$ century to the first half of the $18^{th}$ century. The shape of Sap is deemed to have changed from type I to type II and again from type II to type III In the $17^{th}$ century, which was a time of change, types II and III coexisted. Of the three types of Sap, types II and III re similar because they have two points; thus a noteworthy transit time is thought to have been the middle of the $16^{th}$ century. Type I compared with types II and III is thought to have required more efforts and skills in the production process, and as time passed, the shape and manufacturing methods of Sap are presumed to have been further simplified according to the principle of economy. The simplification of funeral ceremonies is presumed to have been furthered after Imjinwaeran(Japanese invasion of Joseon, 1592~1598), given that as shown in the Annals of King Seonjo, state funerals were suspended several times. In the case of Sap, simplification began from the second half of the $16^{th}$ century, and even in the $18^{th}$ century, rather than separately crafting Sap, Sap was directly drawn on the coffin cover and the coffin. However, in this simplification of form, regulations on the use of Sap specified in Liji were observed, and thus the ceremony was rationally simplified.

Gonadal Maturation and Spawning of River Puffer Takifugu obscurus Indoor Cultured in Low Salinity (저염분에서 사육한 황복 Takifugu obscurus 생식소의 성숙과 산란)

  • Kang, Hee-Woong;Chung, Ee-Yung;Kang, Duk-Young;Park, Young-Je;Jo, Ki-Che;Kim, Gyu-Hee
    • Journal of Aquaculture
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    • v.21 no.4
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    • pp.331-338
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    • 2008
  • Monthly changes in the gonadosomatic index (GSI) and hepatosomatic index (HSI) of wild river puffer Takifugu obscurus, and water quality environment in spawning area during breeding season were investigated from March 1995 to February 1996. Monthly changes in GSI and HSI of T. obscurus, that was cultured in low salinity, were calculated. The external morphology of the gonads, germ cell differentiation during gametogenesis and the reproductive cycle with the gonad developmental phases were investigated by histological analysis. The optimum water quality environment in Ganggyung, Choongcheongnam-do, where is spawning ground of wild T. obscurus, was $15-20^{\circ}C$ (water temperature) and 0 psu (salinity). Monthly changes in the GSI in females and males reached a maximum in May, and then rapidly decreased. Therefore, it is assumed that in the natural condition the spawning period of wild T. obscurus is May to June. In females and males, it showed a negative correlationship between the GSI and HSI. The external morphology of the gonads in female and male T. obscurus, that was cultured in low salinity, is composed of a pair of saccular structure. Based on monthly changes in the GSI, it is assumed that in female T. obscurus, that was cultured in low salinity, spawn from March through May. Therefore, it showed a negative correlationship between changes in the GSI and HSI. On the whole, in females and males, it showed a similar pattern between wild and cultured T. obscurus. The reproductive cycle with the gonad developmental phases can be classified into successive five stages in females: the early growing stage, late growing stage, mature stage, ripe and spent stage, and recovery and resting stage. In males, that can be divided into successive four stages: the growing stage, mature stage, ripe and spent stage, and recovery and resting stage. In case of wild T. obscurus, the spawning period has once a year, however, those cultured in the high water temperature ($20-27^{\circ}C$) - low salinity (under 3.3 psu) condition have reproductive characteristics having possibilities of discharge of eggs and sperms year-round as a multiple spawner.

Analysis of the Perception of Hospice and Narcotic Analgesics by Family Caregivers of Terminal Cancer Patient (말기 암 환자 보호자의 호스피스와 마약성 진통제에 대한 인식도 분석)

  • Kwak, Kyung-Sook;Chun, Sung-Ho;Ha, Jung-Ok;Lee, Kyung-Hee
    • Journal of Hospice and Palliative Care
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    • v.9 no.2
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    • pp.106-111
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    • 2006
  • Purpose: In terminal cancer patients, pain control with narcotic analgesics and supportive care by hospice are very useful treatment modality. However, many patients and their caregivers are poorly compliant in using narcotic analgesics for fear of addiction and tolerance. And also many patients and family caregivers are reluctant to accept hospice, presuming that hospice means patient's condition is no longer reversible and progressively deteriorating. The purpose of this study was to evaluate and analyze the perception of using narcotic analgesics and hospice by family caregivers of terminal cancer patients who play a critical role in health care in Korean culture. Methods: A total of 54 terminal ranter patient's family caregivers participated in this study. Questionnaire consisted of 15 questions about narcotic analgesics and hospice. Results: The study revealed following results. 1) family caregivers who are not aware of hospice are more than half (56.7%). 2) 81.8% of family caregivers agreed that hospice care is beneficial to terminal cancer patients. 3) 85.1% of family caregivers were under financial burden. 4) 83.2% of patient complained pain in 24 hours. 3) while 88.5% of family caregivers believed that narcotic analgesics can control pair, 79.1% and 79.6% of them also believed that use of narcotic analgesics would result in addiction and tolerance, respectively. Conclusion: There still exist barriers to family caregivers in using narcotic analgesics for pain control. And also, terminal cancer patient's family caregivers have poor information about hospice. Therefore, educational intervention about narcotic analgesics by pharmacist and doctors are needed for proper pain control for terminal ranter patients. In addition, more precise information about hospice care should be provided for terminal cancer patients and their family caregivers.

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G-, C-, and NOR-banding of Korean Native Pig Chromosomes (한국재래돼지의 G-, C-, 및 NOR-banding)

  • Sohn, S.H.;Kweon, O.S.;Baik, K.H.;Jung, W.;Cho, E.J.;Kang, M.Y.
    • Journal of Animal Science and Technology
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    • v.45 no.6
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    • pp.901-910
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    • 2003
  • Using the G-, C-, and NOR-banding techniques, a karyotyping for Korean Native Pig was performed. Blood samples were collected from 50 male Korean Native Pigs that had been bred at the National Livestock Research Institute and then blood cells were prepared from in vitro cultures followed by karyotyping; G-, C-, and NOR-banding patterns of metaphase chromosomes were analyzed. The karyotype of Korean Native Pig is 38, XX or XY which consists of 5 pairs of submetacentric chromosomes(Group I), 2 pairs of acrocentric chromosomes with short p-arm(Group II), 5 pairs of medium metacentric chromosomes(Group III), 6 pairs of acrocentric chromosomes(Group IV) and metacentric X and Y sex chromosomes. On GTG-banding, the Korean Native Pig exhibited a typical and identical banding pattern in each homologous chromosomes. Overall chromosomal morphology and positions of typical landmarks of the Korean Native Pig were virtually identical to those of Committee for the Standardized Karyotype of the Domestic Pig(CSKDP). However, numbers of G-bands of the Korean Native Pig chromosomes were more than those of CSKDP. In chromosomes 1, 3, 5, 6, 7, 8, 13, 14, 15, 16, 17, 18 and X, the Korean Native Pig exhibited more separated bands as compared with CSKDP. In C-banding patterns, although the quantity of heterochromatin was variable in each chromosome, most of the Korean Native Pig chromosomes had heterochromatic C-bands on centromeres. However, the heterochromatic C-band was constantly observed on the whole Y chromosome. In AgNOR staining, the NORs were located at centromeres on the chromosomes 8 and 10. The number of NORs per metaphase ranged from 2 to 4 giving a mean value of 2.13. The number of NORs were distributed on all chromosome pair 10 but not on chromosome 8. The sizes of NORs were also differed between homologous chromosomes 8. Numbers of NORs of Korean Native Pig were significantly higher than those of Yorkshire. The pattern of pig NORs was polymorphic in breeds, individuals and cells, especially on chromosome 8.

Surface ultrastructures of the third-stage larvae of Gnathostoma hispidum (돼지악구충(Gnuhostoma hispidum) 제3기 유충의 표면 미세구조)

  • 손운목;이진하
    • Parasites, Hosts and Diseases
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    • v.34 no.3
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    • pp.169-176
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    • 1996
  • A scanning electron microscopic study was performed to observe the surface ultrastructures of the third-stage larvae of Gnathostoma hispidun. The early third-stage larvae (EL3) were collected from the viscera of Chinese loaches by the artificial digestion method . The advanced third-stage larvae (AdL3) were recovered from mice experimentally infected with EL3. Both larval worms were fixed with 2.5% glutaraldehyde, dehydrated in graded alcohol. dryad in critical point dryer, and coated with gold. The specimens were observed with a SEM (DS- l30C). On the head bulb of both larval stage, the mouth had a pair of lateral lips of equal size and of half moon shape. Each lip had a couple of labial papillae and a small amphid located between the two papillae. The hooklets on the head bulb had single-pointed tips and curved posteriorly. The cuticular spines of EL3 were larger and more densely distributed in the anterior area (about 1.8 Mm in length) and gradually decreased in size and number posteriorly. The cuticular spines in the anterior area of AdL3 were sharp-pointed and about 4.5 Mm in length, and those in the middle area were about 1.75 Mm. The velvety cuticular folds and dot-like cuticular spines were distributed in the posterior area. A cervical papilla was located between the 7th and 8th transverse striations. A dome-like body papilla was located at the posterior 1/4 of body. An ellipsoidal excretory pore was located between the 17th and 18th striations. From the above results, it is suggested that the characteristic SEM findings obtained from this study may be helpful on the species identification of larval Gncthostomn.

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Investigating Dynamic Mutation Process of Issues Using Unstructured Text Analysis (비정형 텍스트 분석을 활용한 이슈의 동적 변이과정 고찰)

  • Lim, Myungsu;Kim, Namgyu
    • Journal of Intelligence and Information Systems
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    • v.22 no.1
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    • pp.1-18
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    • 2016
  • Owing to the extensive use of Web media and the development of the IT industry, a large amount of data has been generated, shared, and stored. Nowadays, various types of unstructured data such as image, sound, video, and text are distributed through Web media. Therefore, many attempts have been made in recent years to discover new value through an analysis of these unstructured data. Among these types of unstructured data, text is recognized as the most representative method for users to express and share their opinions on the Web. In this sense, demand for obtaining new insights through text analysis is steadily increasing. Accordingly, text mining is increasingly being used for different purposes in various fields. In particular, issue tracking is being widely studied not only in the academic world but also in industries because it can be used to extract various issues from text such as news, (SocialNetworkServices) to analyze the trends of these issues. Conventionally, issue tracking is used to identify major issues sustained over a long period of time through topic modeling and to analyze the detailed distribution of documents involved in each issue. However, because conventional issue tracking assumes that the content composing each issue does not change throughout the entire tracking period, it cannot represent the dynamic mutation process of detailed issues that can be created, merged, divided, and deleted between these periods. Moreover, because only keywords that appear consistently throughout the entire period can be derived as issue keywords, concrete issue keywords such as "nuclear test" and "separated families" may be concealed by more general issue keywords such as "North Korea" in an analysis over a long period of time. This implies that many meaningful but short-lived issues cannot be discovered by conventional issue tracking. Note that detailed keywords are preferable to general keywords because the former can be clues for providing actionable strategies. To overcome these limitations, we performed an independent analysis on the documents of each detailed period. We generated an issue flow diagram based on the similarity of each issue between two consecutive periods. The issue transition pattern among categories was analyzed by using the category information of each document. In this study, we then applied the proposed methodology to a real case of 53,739 news articles. We derived an issue flow diagram from the articles. We then proposed the following useful application scenarios for the issue flow diagram presented in the experiment section. First, we can identify an issue that actively appears during a certain period and promptly disappears in the next period. Second, the preceding and following issues of a particular issue can be easily discovered from the issue flow diagram. This implies that our methodology can be used to discover the association between inter-period issues. Finally, an interesting pattern of one-way and two-way transitions was discovered by analyzing the transition patterns of issues through category analysis. Thus, we discovered that a pair of mutually similar categories induces two-way transitions. In contrast, one-way transitions can be recognized as an indicator that issues in a certain category tend to be influenced by other issues in another category. For practical application of the proposed methodology, high-quality word and stop word dictionaries need to be constructed. In addition, not only the number of documents but also additional meta-information such as the read counts, written time, and comments of documents should be analyzed. A rigorous performance evaluation or validation of the proposed methodology should be performed in future works.