Subcategorization of intermediate suspicion thyroid nodules based on suspicious ultrasonographic findings

Purpose@#This study compared the malignancy risk of intermediate suspicion thyroid nodules according to the presence of suspicious ultrasonographic (US) findings. @*Methods@#From January 2014 to December 2014, 299 consecutive intermediate suspicion thyroid nodules in 281 patients (mean age, 50.6±12.5 years) with final diagnoses were included in this study. Two radiologists retrospectively reviewed the US findings and subcategorized the intermediate suspicion category into nodules without suspicious findings and nodules with suspicious findings, including punctate echogenic foci, nonparallel orientation, or irregular margins. The malignancy rates were compared between the two subcategory groups. @*Results@#Of the 299 intermediate suspicion thyroid nodules, 230 (76.9%) were subcategorized as nodules without suspicious findings and 69 (23.1%) as nodules with suspicious findings. The total malignancy rate was 33.4% (100/299) and the malignancy rate of nodules with suspicious findings was significantly higher than that of nodules without suspicious findings (47.8% vs. 29.1%, P=0.004). In nodules with suspicious findings, the most common suspicious finding was punctate echogenic foci (48/82, 58.5%) followed by nonparallel orientation (22/82, 26.8%) and irregular margins (12/82, 14.6%). Thirteen nodules had two suspicious findings simultaneously. A linearly increasing trend in the malignancy rate was observed according to the number of suspicious US findings (P for trend=0.001). @*Conclusion@#Intermediate suspicion thyroid nodules with suspicious findings showed a higher malignancy rate than those without suspicious findings. Further management guidelines for nodules with suspicious findings should differ from guidelines for nodules without suspicious findings, even in the same US category.

Helicobacter pylori eradication reduces risk for recurrence of gastric hyperplastic polyp after endoscopic resection

Background/Aims@#Little is known about the effect of Helicobacter pylori eradication on the recurrence of gastric hyperplastic polyps after endoscopic resection. Thus, we evaluated the recurrence rate of gastric hyperplastic polyps based on H. pylori eradication following endoscopic resection. @*Methods@#We retrospectively reviewed the medical records of 201 patients with H. pylori infection who underwent endoscopic resection for gastric hyperplastic polyps at six medical centers. H. pylori status was assessed by histological analysis and a rapid urease test. A total of 149 patients underwent successful H. pylori eradication (eradication group), whereas 52 patients had persistent H. pylori infections (non-eradication group). The recurrence rate of gastric hyperplastic polyps and the risk factors according to H. pylori status were analyzed. @*Results@#During the mean follow-up period of 18.3 months, recurrent gastric polyps developed after endoscopic resection in 10 patients (19.2% [10/52]) in the non-eradication group and 12 patients (8.1% [12/149]) in the eradication group. The cumulative incidence of recurrent gastric hyperplastic polyps was significantly higher in the non-eradication group than in the eradication group (p = 0.041, log‐rank test). In the adjusted analysis, H. pylori eradication reduced the recurrence of gastric hyperplastic polyps (hazard ratio [HR], 0.42; 95% confidence interval [CI], 0.18 to 0.99), whereas anticoagulation therapy increased the risk of recurrence of gastric hyperplastic polyps (HR, 4.91; 95% CI, 1.39 to 17.28). @*Conclusions@#Successful eradication of H. pylori may reduce the recurrence of gastric hyperplastic polyps in patients after endoscopic mucosal resection.

Analysis of the gut microbiome using extracellular vesicles in the urine of patients with colorectal cancer

Background/Aims@#We evaluated the gut microbiome using extracellular vesicles (EVs) in the urine of patients with colorectal cancer (CRC) to determine whether gut-microbe-derived EVs could be a potential biomarker for the diagnosis of CRC. @*Methods@#EVs were isolated from the urine of patients with CRC and healthy controls. DNA was extracted from the EVs, and the bacterial composition was analyzed using next-generation sequencing of the 16S rRNA. @*Results@#A total of 91 patients with CRC and 116 healthy controls were enrolled. We found some specific microbiomes that were more or less abundant in the CRC group than in the control group. The alpha-diversity of the gut microbiome was significantly lower in the CRC group than in the control group. A significant difference was observed in the beta-diversity between the groups. The alpha-diversity indices between patients with early- and late-stage CRC showed conflicting results; however, there was no significant difference in the beta-diversity according to the stage of CRC. There was no difference in the alpha- and beta-diversity of the gut microbiome corresponding to the location of CRC (proximal vs. distal). @*Conclusions@#A distinct gut microbiome is reflected in the urine EVs of patients with CRC compared with that in the healthy controls. Microbial signatures from EVs in urine could serve as potential biomarkers for the diagnosis of CRC.

Prediction of Severity and Adverse Outcomes Associated with Perforation in Patients Presenting to the Emergency Department with Esophageal Injury

Background/Aims@#Esophageal perforation is associated with high mortality and morbidity in patients presenting to the emergency department (ED) with esophageal injury. We investigated the effectiveness of initial CT scan in patients with esophageal injury to determine the risk factors for complications. @*Methods@#Patients admitted through the ED for evaluation of esophageal injuries between January 2001 and May 2020, were investigated. Demographic data, etiological factors, comorbidities, treatment administered, and outcomes were collected. Esophageal injury was graded based on the following CT criteria: (a) normal, (b) pneumomediastinum, (c) mediastinitis, fluid collection, abscess, or overt esophageal wall injury, and (d) pleural effusion, subcutaneous emphysema, or pneumothorax. Grade 2 was defined as microperforation and grades 3 and 4 as overt perforation. @*Results@#Of 281 patients with esophageal injury, 38 had CT-documented overt perforations and 20 had microperforations. Foreign body-induced injury (n=37), Boerhaave syndrome (n=12), and chemical injury (n=3) were common causes of esophageal injury. Complications occurred in 24 (8.5%) patients. Risk factors for complications were age ≥65 years (OR 4.14, 95% CI 1.18~14.56, P=0.027), cerebrovascular disease (OR 8.58, 95% CI 1.13~65.19, P=0.038), Boerhaave syndrome (OR 12.52, 95% CI 2.07~75.68, P=0.006), chemical injury (OR 15.72, 95% CI 3.67~67.28, P<0.001), and CT-documented grade 4 perforation (OR 15.75, 95% CI 4.39~56.55, P<0.001). @*Conclusions@#Initial CT-based grading in the ED are useful for predicting potential complications and for managing patients with esophageal injury and suspected perforation.

Approach to Patients with Consecutive Helicobacter pylori Eradication Failure

Helicobacter pylori (H. pylori) is associated with various gastrointestinal disorders, such as gastritis, peptic ulcers, mucosa-associated lymphoid tissue lymphoma, and gastric cancer. Therefore, the International Agency for Research on Cancer, a specialized cancer agency of the World Health Organization, categorizes H. pylori as a definite gastric carcinogen (group I). H. pylori eradication is a major challenge both medically and socioeconomically in countries with high prevalence of H. pylori and gastric cancer. However, the efficacy of first-line clarithromycin-containing triple therapy and second-line bismuth-containing quadruple therapy continues to decline worldwide including in Korea. The role of salvage therapy is being recognized globally; however, the exact salvage therapy which is useful in daily clinical practice remains unestablished. In this review, factors associated with eradication failure will be discussed. Furthermore, eradication regimens that may be useful as salvage therapies based on Korean guidelines, Maastricht VI/Florence consensus report and previous research are summarized.

Use of Device-Assisted Enteroscopy in Small Bowel Disease: An Expert Consensus Statement by the Korean Association for the Study of Intestinal Diseases / 대한소화기학회지

The introduction of device-assisted enteroscopy (DAE) in the beginning of the 21st century has revolutionized the diagnosis and treatment of diseases of the small intestine. In contrast to capsule endoscopy, the other main diagnostic modality of small bowel diseases, DAE has the unique advantages of allowing the observation of the region of interest in detail and enabling tissue acquisition and therapeutic intervention. As DAE becomes an essential procedure in daily clinical practice, there is an increasing need for correct guidelines on when and how it is to be performed and what technical factors should be taken into consideration. In response to these needs, the Korean Association for the Study of Intestinal Diseases has developed an expert consensus statement on the performance of DAE by reviewing current evidence. This expert consensus statement particularly focuses on the indications, choice of insertion route, therapeutic intervention, complications, and relevant technical points.

Analysis of Risk Factors to Predict Occurrence and Prognosis of Postsurgical Hypertrophic Scar Development: A Review of 4238 Cases

Purpose@#This study aimed to identify the risk factors associated with the occurrence and prognosis of hypertrophic scarring following thyroidectomy. @*Materials and Methods@#A total of 4238 patients who underwent thyroidectomy were included in this study. A multivariable logistic regression model was developed to identify the risk factors for hypertrophic scar development and its prognosis. @*Results@#Our analysis revealed that hypertrophic scar development was associated with younger age [odds ratio (OR)=0.949, p<0.0001], male sex (OR=0.562, p<0.0001), higher body mass index (OR=1.137, p<0.0001), prominent sternocleidomastoid muscles (OR=2.522, p<0.0001), scarring located within 1 cm of the sternal notch (OR=4.345, p<0.0001), and a history of keloid development (OR=2.789, p=0.0031). Additionally, scar location within 1 cm of the sternal notch (beta=4.326, p=0.0429) and a history of keloid development (beta=23.082, p<0.0001) were found to be associated with the prognosis of hypertrophic scarring. @*Conclusion@#The findings of this study provide valuable insights into the risk factors associated with hypertrophic scarring following thyroidectomy. Clinicians can use this information to predict the occurrence of hypertrophic scarring and its prognosis, and take preventative measures accordingly.

Intramuscular Injection of Autologous Serum in Adolescent and Adult Patients with Atopic Dermatitis: A Preliminary Randomized Clinical Trial

Purpose@#The favorable clinical efficacies of intramuscular injection of autologous blood in patients with atopic dermatitis (AD) and intramuscular injection of autologous serum in patients with chronic urticaria have been demonstrated by randomized clinical trials. In this study, we assessed the clinical effectiveness and safety of the intramuscular injection of autologous serum in patients with AD. @*Materials and Methods@#In this randomized, placebo-controlled, and double-blind trial, 23 adolescent and adult patients with moderate-to-severe AD were enrolled. The patients were randomized to receive eight intramuscular injections of 5 mL of autologous serum (n=11) or saline (n=12) over 4 weeks, and were followed up until week 8. Changes in the clinical severity scores of AD assessed by SCORing Atopic Dermatitis (SCORAD), patient-reported Dermatology Life Quality Index (DLQI) score, and incidence of adverse events were assessed from baseline to week 8. @*Results@#One patient in the treatment group and two patients in the placebo group were lost to follow-up before week 8. The intramuscular administration of autologous serum, compared with saline, decreased the SCORAD clinical severity score (-14.8% vs. 10.7%, p=0.006) and improved the DLQI score (-32.6% vs. 19.5%, p=0.01) from baseline to week 8. Serious adverse events were not observed. @*Conclusion@#Intramuscular injection of autologous serum may be effective in treating AD. Further studies are needed to evaluate the clinical usefulness of this intervention for AD (KCT0001969).

Causes of Punctal Plug Loss in Sjögren’s Syndrome

Purpose@#To evaluate the long-term maintenance rate and associated factors of silicone punctal plugs in patients with Sjögren’s syndrome (SS). @*Materials and Methods@#We retrospectively reviewed the medical records of 163 patients with SS who underwent silicone punctal plug insertion between December 2013 and July 2021 at Severance Hospital. The status of punctal plug insertions was classified into the following three categories by the clinician: maintenance, spontaneous loss, and intended removal. Cox proportional hazards model was used to evaluate the risk factors for spontaneous loss. @*Results@#The mean maintenance period was 12.8±15.3 (median 7.07) months. The rate of spontaneous loss was 58%, and the rate of punctal plug removal by the clinician was 14%. The number of prior plug insertions was a risk factor for spontaneous loss [hazard ratio (HR) 1.055, p=0.035]. The upper eyelid punctum was at a higher risk than the lower one (p=0.042). Small-sized plugs showed a significantly higher risk for spontaneous loss than large-sized ones (HR 1.287, p=0.035). Flow-controller type plugs were more vulnerable to spontaneous loss than complete occluders [Micro FlowTM vs. EagleFlex® (HR 2.707, p=0.008) and Micro FlowTM vs. UltraplugTM (HR 3.402, p=0.005)]. The most common reason for removal was tear overflow (5.6%). @*Conclusion@#In repeated insertion, characteristics of the punctal plug, including the type and size, and location of plug insertion, influenced the spontaneous loss of plugs. The management of punctal plugs, including insertion, maintenance, and removal, requires personalized strategies for versatile situations.

Enhanced Bone Formation by Rapidly Formed Bony Wall over the Bone Defect Using Dual Growth Factors

BACKGROUND@#In guided bone regeneration (GBR), there are various problems that occur in the bone defect after the wound healing period. This study aimed to investigate the enhancement of the osteogenic ability of the dual scaffold complex and identify the appropriate concentration of growth factors (GF) for new bone formation based on the novel GBR concept that is applying rapid bone forming GFs to the membrane outside of the bone defect. @*METHODS@#Four bone defects with a diameter of 8 mm were formed in the calvaria of New Zealand white rabbits each to perform GBR. Collagen membrane and biphasic calcium phosphate (BCP) were applied to the bone defects with the four different concetration of BMP-2 or FGF-2. After 2, 4, and 8 weeks of healing, histological, histomorphometric, and immunohistochemical analyses were conducted. @*RESULTS@#In the histological analysis, continuous forms of new bones were observed in the upper part of bone defect in the experimental groups, whereas no continuous forms were observed in the control group. In the histomorphometry, The group to which BMP-2 0.5 mg/ml and FGF-2 1.0 mg/ml was applied showed statistically significantly higher new bone formation. Also, the new bone formation according to the healing period was statistically significantly higher at 8 weeks than at 2, 4 weeks. @*CONCLUSION@#The novel GBR method in which BMP-2, newly proposed in this study, is applied to the membrane is effective for bone regeneration. In addition, the dual scaffold complex is quantitatively and qualitatively advantageous for bone regeneration and bone maintenance over time.

Diagnosis and management of acute colonic diverticulitis: results of a survey among Korean gastroenterologists

Background/Aims@#Some management strategies for acute colonic diverticulitis remain controversial in Korean real-world practice because their clinical features differ from those in the West. This study aimed to investigate the opinions of Korean physicians regarding the diagnosis and treatment of acute diverticulitis. @*Methods@#A web-based survey was conducted among gastroenterologists specializing on treating lower gastrointestinal disorders. The questionnaires concerned overall management strategies for colonic diverticulitis, including diagnosis, treatment, and follow-up. @*Results@#In total, 209 gastroenterologists responded to the survey. Less than one-fourth of the respondents (23.6%) answered that left-sided colonic diverticulitis is more likely to be complicated than right-sided colonic diverticulitis. Most respondents agreed that immunocompromised patients with diverticulitis have worse clinical outcomes than immunocompetent patients (71.3%). Computed tomography was the most preferred tool for diagnosing diverticulitis (93.9%). Approximately 89% of the respondents answered that they believed antibiotic treatment is necessary to treat acute uncomplicated diverticulitis. Most respondents (92.6%) agreed that emergency surgery is not required for diverticulitis with an abscess or microperforation without panperitonitis. Further, 94.7% of the respondents agreed that colon cancer screening is necessary in patients aged ≥ 50 years with diverticulitis after they have recovered from acute illness. Many respondents (71.4%) agreed that surgery for recurrent diverticulitis should be individualized. @*Conclusions@#Opinions regarding management strategies for colonic diverticulitis among Korean gastroenterologists were well agreed upon in some areas but did not agree well in other areas. Evidence-based guidelines that meet the practical needs of the Korean population should be developed.

Case of Concomitant Endoscopic Treatment of Achalasia with Superficial Esophageal Cancer / 대한소화기학회지

Achalasia, a rare motility disorder of the esophagus, is generally accepted as a premalignant disorder. This paper presents the case of a 72-year-old male with achalasia and synchronous superficial esophageal cancer who experienced dysphagia symptoms for five years. As achalasia is associated with an increased risk of esophageal cancer, both can be treated simultaneously if detected at the time of diagnosis. Achalasia and synchronous esophageal cancer are rarely detected and treated endoscopically. This paper reports a case of concurrent successful treatment.

Improvement of Severe Colon Stricture after Rituximab Therapy for Concomitant Mucosa-associated Lymphoid Tissue Lymphoma in a Patient with Ulcerative Colitis / 대한소화기학회지

Colorectal strictures are uncommon in patients with ulcerative colitis (UC). An extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) lymphoma is rarely involved in the colon but may be associated with inflammatory bowel diseases. A 41-year-old female with a six-year history of UC presented with a severe stricture of the sigmoid colon that prevented the passage of a colonoscope. A histological examination revealed non-specific inflammation and fibrosis without dysplasia or cancer.Despite conventional treatment, including mesalazine and azathioprine for one year after that visit, the stricture persisted. In addition, diffuse, edematous exudative inflammation and multiple shallow ulcers were observed in the distal rectum, revealing a MALT lymphoma testing positive for CD20, CD43, CD5, and Bcl-2, but negative for CD3, CD10, CD23, and cyclin-D1. Four weekly doses of rituximab were administered. Follow-up colonoscopy performed one month after treatment revealed slight improvement in the rectal lesion without remnant histological evidence of a MALT lymphoma. In addition, the stricture showed marked improvement, and the colonoscope could pass easily through the stricture site. This is the first case report on an improvement of a severe sigmoid colon stricture in a patient with UC after rituximab treatment for a concomitant rectal MALT lymphoma.

Two Case Reports of Newly Diagnosed Crohn’s Disease after COVID-19 in Pediatric Patients / 대한소화기학회지

Since the coronavirus disease 2019 (COVID-19) outbreak caused by the severe acute respiratory syndrome-coronavirus-2 virus (SARS-CoV-2), various complications have been reported. Although most COVID-19 cases exhibited flu-like symptoms, COVID-19 may dysregulate the immune response and promote overwhelming levels of inflammation in some patients. Inflammatory bowel disease (IBD) is caused by dysregulated or inappropriate immune responses to environmental factors in a genetically susceptible host, and a SARS-CoV-2 infection may act as a possible cause of IBD. This paper describes two pediatric patients who developed Crohn’s disease following a SARS-CoV-2 infection. They were previously healthy before the SARS-CoV-2 infection. On the other hand, they started to develop fever and gastrointestinal symptoms several weeks after recovery from the infection. They were diagnosed with Crohn’s disease by imaging and endoscopic studies, and their symptoms improved after treatment with steroids and azathioprine. This paper suggests that a SARS-CoV-2 infection may trigger IBD in predisposed patients.

Evaluation of the proximal contact and comparison of methods for measuring in normal dentition / 대한치과보철학회지

Purpose@#The aim of this study was to evaluate the proximal contact with a dental floss compared to a celluloid strip and a metal strip in normal dental arch and investigate what the most effective method for measuring is. @*Materials and methods@#The subjects of this study was consisted with 20 healthy adults (10 males and 10 females) who had normal dentition. A dentist with more than 5 years of clinical experience evaluated the proximal contacts using a dental floss method, a celluloid strip method, and a metal strip method. Statistical analysis were performed by the use of Mann-Whitney U test. A P-value < .05 was considered statistically significant in all analysis. In addition, in the evaluation of proximal contact using a dental floss, the measurement of proximal contact using a celluloid strip and a metal strip was compared. @*Results@#80 % of all proximal contact was proper. Proper proximal contact was observed at the posterior area compared to the anterior area (P < .05). And male had proper proximal contact at the anterior area, female had proper proximal contact at the posterior area (P < .05). The consistency analysis between the results of the celluloid strip and the metal strip experiment on the results obtained from the floss using the consistency scale Kappa index shows that using celluloid strip is more advantageous than using the metal strip. @*Conclusion@#Only 80% of all proximal contact was proper. Using celluloid strips with various thickness for evaluating of proximal contact is considered to be helpful for accurate measuring of proximal contact.

A prospective multicenter clinical study on the efficiency of detachable ball- and spring-retained implant prosthesis

PURPOSE@#This prospective clinical study was conducted to evaluate the clinical usefulness of the freely detachable zirconia ball- and spring-retained implant prosthesis (BSRP) through a comparative analysis of screw- and cement-retained implant prosthesis (SCRP). @*MATERIALS AND METHODS@#A multi-center, randomized, prospective clinical study evaluating the clinical usefulness of the detachable zirconia ball- and spring-retained implant prostheses was conducted. Sixty-four implant prostheses in 64 patients were examined. Periodic observational studies were conducted at 0, 3, 6, and 12 months after delivery of the implant prosthesis. Factors such as implant success rate, marginal bone resorption, periodontal pocket depth, plaque and bleeding index, and prosthetic complications were evaluated, respectively. @*RESULTS@#During the 1-year observation period, all implants survived without functional problems and clinical mobility, showing a 100% implant success rate. Marginal bone resorption was significantly higher in the SCRP group than in the BSRP group only at the time of implant prosthesis delivery (P = .043). In all observation periods, periodontal pocket depth was slightly higher in the BSRP group than in the SCRP group, but there was no significant difference (P > .05). The modified plaque index (mPI) scores of both groups were moderate. Higher ratio of a score 2 in modified sulcus bleeding index (mBI) was observed in the BSRP group in the 6- and 12-months observation. @*CONCLUSION@#Within the limitations of this study, the newly developed zirconia ball- and spring-retained implant prosthesis could be considered as an applicable and predictable treatment method along with the existing screw- and cement-retained prosthesis.

The Effect of Psychological Factors on COVID-19 Vaccination Side Effects: A Cross-Sectional Survey in South Korea

Objective@#Side effects from the coronavirus disease-2019 (COVID-19) vaccine, such as pain, headache, nausea, and fatigue, have caused vaccine hesitancy. Research on the effects of psychological factors on COVID-19 vaccine side effects is insufficient. This study aims to investigate the effect of psychological factors on COVID-19 vaccination side effects. @*Methods@#We recruited a total of 226 individuals registered for the COVID-19 vaccine in Seoul, South Korea, for this study. Participants completed a pre-vaccination questionnaire, including the 5C antecedents of vaccination, and a survey of psychological factors (Patient Health Questionnaire–9 [PHQ-9], Generalized Anxiety Disorder–7, Somatic symptom amplification scale [SSAS], and Illness Attitude Scale [IAS]). After vaccination, participants completed an online questionnaire regarding vaccine side effects at 20 minutes, three days, and seven days after vaccination. We added a discrete set of hierarchical variables with vaccine side effects as the dependent variable to the hierarchical regression analysis: demographics for Model 1, 5C antecedents of vaccination for Model 2, and psychological factors for Model 3. @*Results@#Our results indicated that the risk factors for side effects 20 minutes after vaccination were young age, high PHQ, and SSAS scores. Risk factors for side effects three days after vaccination were young age, high constraints, and calculation, and the risk factor for side effects at seven days was a high IAS score. @*Conclusion@#Our study confirmed that there is a significant relationship between psychological factors and COVID-19 vaccine side effects in chronological order. Psychosocial factors should be examined when assessing side-effect reactions to the COVID-19 vaccine.

Improvement of the intestinal epithelial barrier during laxative effects of phlorotannin in loperamide‑induced constipation of SD rats / 한국실험동물학회지

Background@#Disruptions of the intestinal epithelial barrier (IEB) are frequently observed in various digestive diseases, including irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD). This study assessed the improvement in the IEB during the laxative activity of phlorotannin (Pt) harvested from Ecklonia cava in constipation by examining the changes in the expression of the regulatory proteins for the tight junction (TJ) and adherens junction (AJ), and inflammatory cytokines in Sprague Dawley (SD) rats with loperamide (Lm)-induced constipation after a Pt treatment. @*Results@#The Pt treatment induced laxative activity, including the improvement of feces-related parameters, gastrointestinal transit rate, and histological structure of the mid colon in Lm-treated SD rats. In addition, significant recovery effects were detected in the histology of IEB, including the mucus layer, epithelial cells, and lamina propria in the midcolon of Lm + Pt treated SD rats. The expression levels of E-cadherin and p120-catenin for AJ and the ZO-1, occludin, and Claudin-1 genes for TJ in epithelial cells were improved remarkably after the Pt treatment, but the rate of increase was different. Furthermore, the Pt treatment increased the expression level of several inflammatory cytokines, such asTNF-α, IL-6, IL-1β, IL-13, and IL-4 in Lm + Pt treated SD rats. @*Conclusions@#These results provide the first evidence that the laxative activity of Pt in SD rats with Lm-induced constipation phenotypes involve improvements in the IEB.

Comparison of immunophenotypes between Rag2 knockout mice derived from two different sources / 한국실험동물학회지

Background@#Recombination activating gene2 (Rag2) knockout (KO) mice are used widely in various research fields, including vaccine development, transplantation studies, and hematopoiesis research, but few studies have compared their phenotypes. This study examined whether there were differences in the immunophenotypes between Rag2 KO mice derived from different sources. In particular, the changes in the organ weight, histological structure, and subpopulation of T and B cells were compared in the spleen and thymus of C57BL/6-Rag2em1hwl/Korl (Rag2/Korl KO) and B6.Cg-Rag2tm1.1Cgn/J (Rag2/J KO) mice. @*Results@#The weight of the spleen and thymus similarly decreased in the Rag2/Korl and Rag2/J KO mice compared to their wild type (WT) mice, even though the other organs were kept at the same weight. A slight difference between the Rag2/Korl and Rag2/J KO group were detected in the number of white blood cells (WBC), lymphocytes (LYM), red cell distribution width (RDW), and platelets (PLT). In addition, the white pulp of the spleen and the cortex region of the thymus decreased in both Rag2 KO mice compared to WT mice. On the other hand, significant differences in the number of CD8+ T and B cell subpopulations between WT and Rag2 KO mice were observed between Rag2/Korl and Rag2/J KO group, while the CD4+ T subpopulation was maintained similarly in both groups. @*Conclusions@#These results suggest that Rag2/Korl and Rag2/J KO mice exhibit similar immunophenotypes in the spleen and thymus except for the differences in the number of CD8+ T and B cell subpopulations.

Omega-3 fatty acids upregulate Nrf2 expression and attenuate apoptosis, inflammation, and fibrosis in a rat model of cyclosporine-induced nephropathy / 고신대학교의과대학학술지

Background@#Cyclosporine A (CsA)-induced kidney injury is characterized by renal impairment with inflammatory cell infiltrations, apoptosis, fibrosis, and hypoxic injury. It is not clear whether omega-3 fatty acids (O-3 FAs), which have anti-inflammatory and antioxidant roles, affect nuclear factor erythroid 2-related factor 2 (Nrf2) expression. The aim of this study was to investigate whether O-3 FAs affect Nrf2 expression and exert anti-inflammatory, anti-apoptotic, and anti-fibrotic effects in CsA-induced nephropathy. @*Methods@#Male Sprague-Dawley rats were divided into control, CsA-treated, and CsA-treated with O-3 FA groups. Nrf2 expression was measured by Western blots and immunohistochemical staining. @*Results@#Kidney function was impaired in the CsA-treated rats compared to the controls. Caspase-3 and caspase-7 were activated in the CsA-treated group, and the Bax/Bcl2 ratio was higher. O-3 FAs attenuated these apoptosis-related changes. ED-1 and inhibition of kappa B (IĸB) protein expression were significantly upregulated in the CsA-treated group. Compared to the control group, O-3 FA supplementation attenuated the increased expression of ED-1 and IĸB related to inflammation. Smad2/3, Smad4, and transforming growth factor-β1 were activated in the CsA group, and O-3 FA treatment prevented these changes related to renal fibrosis. The expression of Nrf2 was reduced in CsA-treated rats, but Nrf-2 was increased by O-3 FA treatment. @*Conclusions@#We suggest that Nrf2 is a potential mediator induced by O-3 FA supplementation and that it attenuates pro-inflammatory pathways, fibrotic processes, and apoptosis. Further studies are needed to elucidate the crosstalk between Nrf2 expression and signals related to O-3 FA treatment.