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Background/Aims@#Endoscopic papillectomy (EP) is increasingly used as an alternative to surgery for managing benign ampullary neoplasms. However, post-EP resection margins are often positive or indeterminate, and there is no consensus on the management of ampullary adenomas with positive or indeterminate margins after EP. This study was designed to compare the longterm outcomes between resected margin-negative (RMN) and resected margin-positive/indeterminate (RMPI) groups and to identify factors associated with clinical outcomes. @*Methods@#This retrospective analysis included patients with ampullary adenoma without evidence of adenocarcinoma who underwent EP between 2004 and 2016. The RMN and RMPI groups were compared for recurrence rates and recurrence-free duration during a mean followup duration of 71.7±39.8 months. Factors related to clinical outcomes were identified using multivariate analysis. @*Results@#Of the 129 patients who underwent EP, 82 were in the RMN group and 47 were in the RMPI group. The RMPI group exhibited a higher recurrence rate compared to the RMN group (14.6% vs 34.0%, p=0.019). However, the recurrence-free duration was not significantly different between the groups (34.7±32.6 months vs 36.2±27.4 months, p=0.900). Endoscopic treatment successfully managed recurrence in both groups (75% vs 75%). Submucosal injection was a significant risk factor for residual lesions (hazard ratio, 4.11; p=0.009) and recurrence (hazard ratio, 2.57; p=0.021). @*Conclusions@#Although ampullary adenomas with positive or indeterminate margins after EP showed a higher rate of recurrence at long-term follow-up, endoscopic treatment was effective with favorable long-term outcomes. Submucosal injection prior to resection was associated with increased risk of recurrence and residual lesions.
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Post-tuberculosis lung disease (PTLD) is emerging as a significant area of global interest. As the number of patients surviving tuberculosis (TB) increases, the subsequent long-term repercussions have drawn increased attention due to their profound clinical and socioeconomic impacts. A primary obstacle to its comprehensive study has been its marked heterogeneity. The disease presents a spectrum of clinical manifestations which encompass tracheobronchial stenosis, bronchiectasis, granulomas with fibrosis, cavitation with associated aspergillosis, chronic pleural diseases, and small airway diseases—all persistent consequences of PTLD. The spectrum of symptoms a patient may experience varies based on the severity of the initial infection and the efficacy of the treatment received. As a result, the long-term management of PTLD necessitates a detailed and specific approach, addressing each manifestation individually—a tailored strategy. In the immediate aftermath (0–12 months after anti-TB chemotherapy), there should be an emphasis on monitoring for relapse, tracheobronchial stenosis, and smoking cessation. Subsequent management should focus on addressing hemoptysis, managing infection including aspergillosis, and TB-associated chronic obstructive pulmonary disease or restrictive lung function. There remains a vast expanse of knowledge to be discovered in PTLD. This review emphasizes the pressing need for comprehensive, consolidated guidelines for management of patients with PTLD.
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Background@#This study aimed to identify the incidence rate of post-coronavirus disease-2019 (COVID-19) conditions in the Republic of Korea (ROK) Army and to investigate the trend of the incidence rate according to changes in dominant variants. @*Methods@#We used the results of a 19-item, self-completed survey of those who had recovered from COVID-19 in the ROK Army between March 24, 2020, and April 30, 2022. We used both descriptive and multiple logistic regression analyses to identify factors associated with the incidence rate of post-COVID-19 conditions. @*Results@#Among the total of 48,623 COVID-19 episodes in the ROK Army, the overall incidence rate of post-COVID-19 conditions was 32.9%. Based on the survey, the incidence of cough was the highest at 15.4%, followed by fatigue (15.1%) and sputum (13.8%). The delta variant had the highest incidence rate of post-COVID-19 conditions at 50.7%, whereas the omicron variant had the lowest at 19.7%. Concerning the type of post-COVID-19 condition, the neuropsychiatric symptoms had the highest incidence at 27.4% when the delta variant was dominant, and the respiratory symptoms were highest at 37.3% when the omicron variant was dominant. In the case of smell and taste symptoms, the incidence rate was high at 21.1% only when the delta variant was predominant. @*Conclusion@#The overall incidence rate of post-COVID-19 conditions in the ROK Army was 32.9%. When the delta variant was dominant, the overall incidence as well as the proportion of neuropsychiatric symptoms were high. However, as the omicron variant became dominant, the overall incidence decreased, but the proportion of respiratory symptoms increased.
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Purpose@#The benefit of adjuvant chemotherapy following curative-intent surgery in pancreatic ductal adenocarcinoma (PDAC) patients who had received neoadjuvant FOLFIRINOX is unclear. This study aimed to assess the survival benefit of adjuvant chemotherapy in this patient population. @*Materials and Methods@#This retrospective study included 218 patients with localized non-metastatic PDAC who received neoadjuvant FOLFIRINOX and underwent curative-intent surgery (R0 or R1) between January 2017 and December 2020. The association of adjuvant chemotherapy with disease-free survival (DFS) and overall survival (OS) was evaluated in overall patients and in the propensity score matched (PSM) cohort. Subgroup analysis was conducted according to the pathology-proven lymph node status. @*Results@#Adjuvant chemotherapy was administered to 149 patients (68.3%). In the overall cohort, the adjuvant chemotherapy group had significantly improved DFS and OS compared to the observation group (DFS: median, 13.8 months [95% confidence interval (CI), 11.0 to 19.1] vs. 8.2 months [95% CI, 6.5 to 12.0]; p < 0.001; and OS: median, 38.0 months [95% CI, 32.2 to not assessable] vs. 25.7 months [95% CI, 18.3 to not assessable]; p=0.005). In the PSM cohort of 57 matched pairs of patients, DFS and OS were better in the adjuvant chemotherapy group than in the observation group (p < 0.001 and p=0.038, respectively). In the multivariate analysis, adjuvant chemotherapy was a significant favorable prognostic factor (vs. observation; DFS: hazard ratio [HR], 0.51 [95% CI, 0.36 to 0.71; p < 0.001]; OS: HR, 0.45 [95% CI, 0.29 to 0.71; p < 0.001]). @*Conclusion@#Among PDAC patients who underwent surgery following neoadjuvant FOLFIRINOX, adjuvant chemotherapy may be associated with improved survival. Randomized studies should be conducted to validate this finding.
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Background/Aims@#There are limitations in treating ampullary adenomas with intraductal extension using conventional endoscopic modalities. Endoscopic intraductal radiofrequency ablation (ID-RFA) may be useful for treating intraductal (common bile duct [CBD] and/or pancreatic duct [PD]) extensions of ampullary adenomas, but long-term data are lacking. We thus evaluated the long-term outcomes of endoscopic ID-RFA for managing ampullary adenomas with intraductal extension. @*Methods@#Prospectively collected endoscopic ID-RFA database at Asan Medical Center was reviewed to identify consecutive patients with ampullary adenoma who underwent ID-RFA for intraductal extension between January 2018 and August 2021. Technical success, short-term and long-term clinical success, and adverse events were evaluated. @*Results@#A total of 29 patients (14 CBD, 1 PD, and 14 CBD and PD) were analyzed. All patients had undergone endoscopic snare papillectomy prior to ID-RFA. A median of one session of IDRFA (range, 1 to 3) for residual or relapsed intraductal extension of ampullary adenoma were successfully performed (technical success=100%). Both biliary and pancreatic stenting were routinely performed after ID-RFA to prevent ductal stricture. After a median follow-up of 776 days (interquartile range, 470 to 984 days), the short-term and long-term clinical success rates were 93% and 76%, respectively. Seven patients experienced procedural adverse events and three patients developed ductal strictures. @*Conclusions@#Endoscopic ID-RFA showed good long-term outcomes in treating residual or relapsed ampullary adenomas with intraductal extension. Repeated ID-RFA may be considered as an option for managing recurrence. Further studies are needed to standardize the procedure.
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Nigrospora (Xylariales, Apiosporaceae) consists of species of terrestrial plant endophytes and pathogens. Nigrospora has also been reported in marine environments such as mangroves, sea fans, and macroalgae. However, limited research has been conducted on Nigrospora associated with macroalgae. Here, we isolated Nigrospora species from three types of algae (brown, green, and red algae) from Korean islands (Chuja, Jeju, and Ulleung) based on phylogenetic analyses of multigenetic markers: the internal transcribed spacers (ITS), betatubulin (BenA), and translation elongation factor 1 (TEF1-α). A total of 17 Nigrospora strains were isolated from macroalgae and identified as nine distinct species. The majority of Nigrospora species (seven) were found on brown algae, followed by red algae (three), and then green algae (two). To our understanding, this study represents the first account of N.cooperae, N. covidalis, N. guilinensis, N. lacticolonia, N. osmanthi, N. pyriformis, and N. rubi occurring in marine environments. Additionally, this study provides the first report of the occurrence of N. cooperae, N. covidalis, N. guilinensis, N. lacticolonia, and N. osmanthi in South Korea. This study will provide valuable insights for future research exploring the func tions of fungi in macroalgal communities.
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Background/Aims@#Endoscopic ultrasonography (EUS) provides high-resolution images and is superior to computed tomography (CT) scan in diagnosing small pancreatic ductal adenocarcinoma (PDAC). As a result, the use of EUS for early detection of PDAC has attracted attention. This study aimed to identify the clinical and radiological characteristics of patients with PDAC diagnosed by EUS but not found on CT scan. @*Methods@#The medical records of patients diagnosed with PDAC at 12 tertiary referral centers in Korea from January 2003 to April 2019 were reviewed. This study included patients with pancreatic masses not clearly observed on CT scan but identified on EUS. The clinical characteristics and radiological features of the patients were analyzed, and survival analysis was performed. @*Results@#A total of 83 patients were enrolled. The most common abnormal CT findings other than a definite mass was pancreatic duct dilatation, which was identified in 61 patients (73.5%). All but four patients underwent surgery. The final pathologic stages were as follows: IA (n=31, 39.2%), IB (n=8, 10.1%), IIA (n=20, 25.3%), IIB (n=17, 21.5%), III (n=2, 2.5%), and IV (n=1, 1.4%). The 5-year survival rate of these patients was 50.6% (95% confidence interval, 38.8% to 66.7%). Elevated liver function testing and R1 resection emerged as significant predictors of mortality in the multivariable Cox regression analysis. @*Conclusions@#This multicenter study demonstrated favorable long-term prognosis in patients with PDAC diagnosed by EUS but indeterminate on CT scan. EUS should be considered for patients with suspected PDAC but indeterminate on CT scan.
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Penicillium species have been actively studied in various fields, and many new and unrecorded species continue to be reported in Korea. Moreover, unidentified and misidentified Korean Penicillium species still exist in GenBank. Therefore, it is necessary to revise the Korean Penicillium inventory based on accurate identification. We collected Korean Penicillium nucleotide sequence records from GenBank using the newly developed software, GenMine, and re-identified Korean Penicillium based on the maximum likelihood trees. A total of 1681 Korean Penicillium GenBank nucleotide sequence records were collected from GenBank. In these records, 1208 strains with four major genes (Internal Transcribed Spacer rDNA region, b-tubulin, Calmodulin and RNA polymerase II) were selected for Penicillium reidentification. Among 1208 strains, 927 were identified, 82 were identified as other genera, the rest remained undetermined due to low phylogenetic resolution. Identified strains consisted of 206 Penicillium species, including 156 recorded species and 50 new species candidates. However, 37 species recorded in the national list of species in Korea were not found in GenBank. Further studies on the presence or absence of these species are required through literature investigation, additional sampling, and sequencing. Our study can be the basis for updating the Korean Penicillium inventory.
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Purpose@#This study evaluated the efficacy of adjuvant chemotherapy (AC) in patients with resected ampulla of Vater (AoV) carcinoma. @*Materials and Methods@#Data from 646 patients who underwent surgical resection at Asan Medical Center between 2000 and 2017 were retrospectively reviewed. @*Results@#The median age of the patients was 62 years, and 54.2% were male. Patients were classified into AC group (n=165, 25.5%) and no AC group (n=481, 74.5%). With a median follow-up duration of 88 months, in patients with stage I, II, III, median recurrence-free survival (RFS) was not reached, 44 months, and 15 months, respectively, and the median overall survival (OS) were not reached, 88 months and 35 months, respectively. Despite no statistical significance, RFS and OS were better in stage II patients with AC than in those without AC (median RFS, 151 months vs. 38 months; p=0.156 and median OS, 153 months vs. 74 months; p=0.299). In multivariate analysis for RFS and OS, TNM stage, R1 resection status, presence of lymphovascular invasion, and perineural invasion remained significant factors, whereas AC (hazard ratio [HR], 0.74; 95% confidence interval [CI], 0.54 to 1.00; p=0.052) was marginally related with RFS. After propensity score matching in only stage II/III patients, RFS and OS with AC were numerically longer than those without AC (HR, 0.80; 95% CI, 0.60 to 1.06; p=0.116 and HR, 0.77; 95% CI, 0.56 to 1.06; p=0.111). @*Conclusion@#AC with fluoropyrimidine did not improve survival of patients with resected AoV carcinoma. However, multivariate analysis with prognostic factors showed a marginally significant survival benefit with AC.
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Purpose@#The clinical implications of bowel wall thickening (BWT) on abdominal computed tomography (CT) among children are unknown. We aimed to suggest a new method for measuring BWT and determining its clinical significance in children. @*Methods@#We retrospectively analyzed 423 patients with acute abdomen who underwent abdominal CT; 262 were classified into the BWT group. For this group, the pediatric radiologist described the maximal bowel wall thickness (MT), normal bowel wall thickness (mm) (NT), and their ratios for each segment of the bowel wall. @*Results@#In the thickened bowel walls, the thickness differed significantly between the small bowel (6.83±2.14 mm; mean±standard deviation) and the colon (8.56±3.46 mm; p<0.001). The ratios of MT to NT in the small bowel (6.09±3.17) and the colon (7.58±3.70) were also significantly different (p<0.001). In the BWT group, 35 of 53 patients had positive fecal polymerase chain reaction results; 6 patients infected with viruses predominantly had BWT in the small intestine, while the terminal ileum and the colon were predominantly affected in 29 patients with bacterial infections. In the initially undiagnosed 158 patients with BWT, the symptoms improved spontaneously without progression to chronic gastrointestinal disease. @*Conclusion@#This study provides a clinical reference value for BWT in the small intestine and colon using a new method in children. The BWT on abdominal CT in children might indicate nonspecific findings that can be observed and followed up without additional evaluation, unlike in adults.
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Purpose@#This study evaluated the efficacy of adjuvant chemotherapy (AC) in patients with resected ampulla of Vater (AoV) carcinoma. @*Materials and Methods@#Data from 646 patients who underwent surgical resection at Asan Medical Center between 2000 and 2017 were retrospectively reviewed. @*Results@#The median age of the patients was 62 years, and 54.2% were male. Patients were classified into AC group (n=165, 25.5%) and no AC group (n=481, 74.5%). With a median follow-up duration of 88 months, in patients with stage I, II, III, median recurrence-free survival (RFS) was not reached, 44 months, and 15 months, respectively, and the median overall survival (OS) were not reached, 88 months and 35 months, respectively. Despite no statistical significance, RFS and OS were better in stage II patients with AC than in those without AC (median RFS, 151 months vs. 38 months; p=0.156 and median OS, 153 months vs. 74 months; p=0.299). In multivariate analysis for RFS and OS, TNM stage, R1 resection status, presence of lymphovascular invasion, and perineural invasion remained significant factors, whereas AC (hazard ratio [HR], 0.74; 95% confidence interval [CI], 0.54 to 1.00; p=0.052) was marginally related with RFS. After propensity score matching in only stage II/III patients, RFS and OS with AC were numerically longer than those without AC (HR, 0.80; 95% CI, 0.60 to 1.06; p=0.116 and HR, 0.77; 95% CI, 0.56 to 1.06; p=0.111). @*Conclusion@#AC with fluoropyrimidine did not improve survival of patients with resected AoV carcinoma. However, multivariate analysis with prognostic factors showed a marginally significant survival benefit with AC.
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The genus Laccaria (Hydnangiaceae, Agaricales) plays an important role in forest ecosystems as an ectomycorrhizal fungus, contributing to nutrient cycles through symbiosis with many types of trees. Though understanding Laccaria diversity and distribution patterns, as well as its association with host plants, is fundamental to constructing a balanced plant diversity and conducting effective forest management, previous studies have not been effective in accurately investigating, as they relied heavily on specimen collection alone. To investigate the true diversity and distribution pattern of Laccaria species and determine their host types, we used four different approaches: specimen-based analysis, open database search (ODS), NGS analysis, and species-specific PCR (SSP). As a result, 14 Laccaria species have been confirmed in Korea. Results regarding the species distribution pattern were different between specimen-based analysis and SSP. However, when both were integrated, the exact distribution pattern of each Laccaria species was determined. In addition, the SSP revealed that many Laccaria species have a wide range of host types. This study shows that using these four different approaches is useful in determining the diversity, distribution, and host of ECM fungi. Furthermore, results obtained for Laccaria will serve as a baseline to help understand the role of ECM fungi in forest management in response to climate change.
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Purpose@#The clinical implications of bowel wall thickening (BWT) on abdominal computed tomography (CT) among children are unknown. We aimed to suggest a new method for measuring BWT and determining its clinical significance in children. @*Methods@#We retrospectively analyzed 423 patients with acute abdomen who underwent abdominal CT; 262 were classified into the BWT group. For this group, the pediatric radiologist described the maximal bowel wall thickness (MT), normal bowel wall thickness (mm) (NT), and their ratios for each segment of the bowel wall. @*Results@#In the thickened bowel walls, the thickness differed significantly between the small bowel (6.83±2.14 mm; mean±standard deviation) and the colon (8.56±3.46 mm; p<0.001). The ratios of MT to NT in the small bowel (6.09±3.17) and the colon (7.58±3.70) were also significantly different (p<0.001). In the BWT group, 35 of 53 patients had positive fecal polymerase chain reaction results; 6 patients infected with viruses predominantly had BWT in the small intestine, while the terminal ileum and the colon were predominantly affected in 29 patients with bacterial infections. In the initially undiagnosed 158 patients with BWT, the symptoms improved spontaneously without progression to chronic gastrointestinal disease. @*Conclusion@#This study provides a clinical reference value for BWT in the small intestine and colon using a new method in children. The BWT on abdominal CT in children might indicate nonspecific findings that can be observed and followed up without additional evaluation, unlike in adults.
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Background/Aims@#The natural history of spontaneous decrease in the size of pancreatic cystic lesions (PCLs) without high-risk stigmata is under investigation. This study aimed to investigate the timing of spontaneous decrease in the size of PCLs without high-risk stigmata and to identify the characteristics associated with their complete resolution. @*Methods@#From 2000 to 2016, patients with spontaneous decreases in PCL size on computed tomography (CT) and/or magnetic resonance imaging (MRI) who had at least 1 year of follow-up were evaluated retrospectively. @*Results@#A total of 78 patients underwent follow-up for an average of 55.7 months. Most patients were asymptomatic, and 35 (37.2%) showed complete resolution. The initial mean PCL size was 1.6±0.9 cm (range, 0.5 to 5.6 cm). The average time to initial decrease in size and complete resolution of PCLs were 32.1 and 41.5 months, respectively. Compared with PCLs that completely resolved, presence of underlying malignancy was associated with partial resolution of PCLs in multivariable analysis (hazard ratio, 0.51; 95% confidence interval, 0.32 to 0.81; p=0.005). Endoscopic ultrasound (EUS) identified detailed findings, especially the presence of septum (p<0.001), calcification (p=0.015) and lobulation (p=0.001) that were not found on CT/MRI. @*Conclusions@#Asymptomatic small PCLs without high-risk stigmata can naturally decrease in size at approximately 3 years, and complete resolution can be expected in the absence of underlying malignancy.Regular follow-up of approximately 3 years with EUS may be a reasonable and safe alternative when planning the initial treatment of small PCLs without high-risk stigmata.
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Background/Aims@#Interventional endoscopists may utilize contrast-enhanced harmonic endoscopic ultrasound (CEHEUS) for image guidance during radiofrequency ablation (RFA) because of its capability to delineate real-time tumor perfusion dynamics. The purpose of this study was to assess the utility of CEH-EUS for the guidance and monitoring of en-doscopic RFA. @*Methods@#Nineteen consecutive patients with solid abdominal tumors who underwent CEH-EUS and endo-scopic RFA were included. The extent of the ablation was as-sessed by CEH-EUS at 5 to 7 days after RFA. Additional RFAs were performed under CEH-EUS guidance. @*Results@#The diag-noses were as follows: nonfunctioning neuroendocrine tumor (n=13), solid pseudopapillary neoplasm (SPN) (n=2), insu-linoma (n=1), left adrenal adenoma (n=2), and left adrenal oligometastasis (n=1). Pre-CEH-EUS findings revealed that 17 cases showed hyperenhanced patterns and two cases of SPN showed isoenhanced patterns. CEH-EUS-assisted RFA was technically feasible in all 19 patients. After the first RFA session, seven patients of the treated tumors showed the disappearance of intratumoral enhancement on CEH-EUS, whereas 12 showed residual contrast enhancement. Twelve patients with incomplete ablation were further treated with additional RFA under real-time CEH-EUS guidance. Radiolog-ic complete response was observed in 13 patients (68.4%). Among the 35 ablation procedures, the only adverse events were two episodes of pancreatitis (5.7%; 1 moderate and 1mild). During the median follow-up of 28 months, the local recurrence rate was 7.7%. @*Conclusions@#The application of CEH-EUS for RFA could be helpful in assessing early treat-ment response after ablation and targeting residual viable tumors during additional ablation sessions.
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BACKGROUND/AIMS: Type 2 autoimmune pancreatitis (AIP) has been considered extremely rare in East Asia. This study aimed to clarify the prevalence, clinical characteristics and radiological findings of type 2 AIP highlighting patients presenting as acute pancreatitis in a single center. METHODS: Type 2 AIP patients were classified according to International Consensus Diagnostic Criteria. Radiological findings were compared between type 2 AIP presenting as acute pancreatitis and gallstone pancreatitis. RESULTS: Among 244 patients with AIP, 27 (11.1%) had type 2 AIP (definite, 15 [55.5%] and probable 12 [44.5%]). The median age of patients with type 2 AIP was 29 years (interquartile range, 20 to 39 years). Acute pancreatitis was the most common initial presentation (n=17, 63%) while obstructive jaundice was present in only one patient. Ulcerative colitis (UC) was associated with type 2 AIP in 44.4% (12/27) of patients. Radiological pancreatic imaging such as delayed enhancement of diffusely enlarged pancreas, homogeneous enhancement of focal enlargement/mass, absent/minimal peripancreatic fat infiltration or fluid collection, and multifocal main pancreatic duct narrowings were helpful for differentiating type 2 AIP from gallstone pancreatitis. During follow-up (median, 32.3 months), two patients (2/25, 8%) experienced relapse. CONCLUSIONS: In South Korea, type 2 AIP is not as rare as previously thought. Overall, the clinical profile of type 2 AIP was similar to that of Western countries. Type 2 AIP should be considered in young UC patients with acute pancreatitis of uncertain etiology.
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Humanos , Colitis Ulcerosa , Consenso , Asia Oriental , Estudios de Seguimiento , Cálculos Biliares , Ictericia Obstructiva , Corea (Geográfico) , Páncreas , Conductos Pancreáticos , Pancreatitis , Prevalencia , RecurrenciaRESUMEN
In the version of this article initially published, the fifth author's name was stated as “Joo Nam Lee.
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Imiquimod, a toll-like receptor agonist, is a topical immunomodulator that induces the production of several cytokines including interferon-alpha, which shows antifibrotic properties. We hypothesized that the antifibrotic effect of imiquimod would soften fibrotic skin lesions. Therefore, we applied topical imiquimod with topical tacrolimus or systemic acitretin in patients with refractory lesions of myxedema, angiolymphoid hyperplasia, and generalized discoid lupus erythematosus and confirmed improvement in fibrotic lesions in these patients. Thus, we conclude that use of imiquimod improves fibrotic skin lesions. This report describes our experience with the treatment of this condition along with a review of the related literature.
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Humanos , Acitretina , Hiperplasia Angiolinfoide con Eosinofilia , Citocinas , Fibrosis , Hiperplasia , Interferón-alfa , Lupus Eritematoso Discoide , Mixedema , Piel , Tacrolimus , Receptores Toll-LikeRESUMEN
PURPOSE@#The aim of this study was to confirm the applicability of YouTube as a delivery platform of lecture videos for dental students and to assess their learning attitudes towards the flipped classroom model.@*METHODS@#Learning experiences after using the YouTube platform to deliver preliminary video lectures in a flipped classroom were assessed by 69 second-year students (52 males, 17 females) at Dankook University College of Dentistry, Korea, who attended periodontology lectures during 2 consecutive semesters of the 2016 academic year. The instructor uploaded the lecture videos to YouTube before each class. At the end of the second semester, the students were surveyed using a questionnaire devised by the authors.@*RESULTS@#Of the students, 53 (76.8%) always watched the lecture before the class, 48 (69.6%) used their smartphones, and 66 (95.7%) stated that they watched the lectures at home. The majority of the students replied that the video lectures were easier to understand than face to face lectures (82.6%) and that they would like to view the videos again after graduation (73.9%).@*CONCLUSION@#Our results indicate that YouTube is an applicable platform to deliver video lectures and to expose students to increased learning opportunities.