Stem cells are the foundational cells for every organ and tissue in our body. Cell-based therapeutics using stem cells in regenerative medicine have received attracting attention as a possible treatment for various diseases caused by congenital defects. Stem cells such as induced pluripotent stem cells (iPSCs) as well as embryonic stem cells (ESCs), mesenchymal stem cells (MSCs), and neuroprogenitors stem cells (NSCs) have recently been studied in various ways as a cell-based therapeutic agent. When various stem cells are transplanted into a living body, they can differentiate and perform complex functions. For stem cell transplantation, it is essential to determine the suitability of the stem cell-based treatment by evaluating the origin of stem, the route of administration, In vivo bio-distribution, transplanted cell survival, function, and mobility. Currently, these various stem cells are being imaged In vivo through various molecular imaging methods. Various imaging modalities such as optical imaging, magnetic resonance imaging (MRI), ultrasound (US), positron emission tomography (PET), and single-photon emission computed tomography (SPECT) have been introduced for the application of various stem cell imaging. In this review, we discuss the principles and recent advances of In vivo molecular imaging for application of stem cell research.

Background: This study presents a novel technical tip for intraoperative tumor localization and determination of the proximal resection line using a titanium ring strip for totally laparoscopic distal gastrectomy in patients with middle-third gastric cancer and describes the short-term results of its application. Methods: In total, 42 patients with middle-third gastric cancer who underwent intraoperative tumor localization using a titanium ring strip and determination of the proximal resection line through intraoperative radiography between January 2020 and December 2021 were enrolled in this study. We retrospectively analyzed patients’ prospectively collected clinical, pathological, and surgical data. Results: Twenty-six men and 16 women with a mean age of 58.3±12.5 years were enrolled. The mean operation time and estimated blood loss were 212.6±43.0 minutes and 122.4±77.6 mL, respectively. The lengths of the proximal and distal resection margin were 2.0±0.4 cm (range, 0.8–3.7 cm) and 10.5±4.1 cm (range, 0.4–20.4 cm), respectively. Roux-en-Y anastomosis was performed in 30 patients, while Billroth II with Braun anastomosis was performed in 12 patients. There were no procedure-related complications, and the mean postoperative hospital stay was 7.2±1.9 days. For all patients, the negative proximal resection margin was confirmed by postoperative pathological examinations. Conclusions Intraoperative tumor localization and determination of the proximal resection line using a titanium ring strip is a useful alternative method that can be easily and safely performed. This method is especially useful for patients with middle-third gastric cancer requiring an appropriate proximal resection margin.

Background: Delta ceramic-on-ceramic (CoC) articulation affords excellent outcomes in primary total hip arthroplasty (THA). However, the safety and reliability of this bearing in revision THA need more evidence. This study aimed to report complications, radiological changes, clinical results, and survivorship of revision THA using Delta CoC articulation at minimum 5-year follow-up. Methods: We reviewed 118 revision THAs (113 patients: 68 men and 45 women) performed with use of Delta CoC bearing. Their mean age was 58.7 years (range, 30–90 years) and their mean body mass index was 24.6 kg/m 2 (range, 15.2–32.5 kg/m 2 ). These patients were followed up for 5–12 years (mean, 7.2 years). We evaluated squeak, grinding sensation, ceramic fracture, dislocation, periprosthetic joint infection (PJI), periprosthetic fracture, prosthetic loosening, ceramic wear, osteolysis, modified Harris hip score (mHHS), and survivorship with any reoperation after the revision as the endpoint. Results: Two patients (1.7%) had grinding sensation, but no patient had ceramic fracture. Reoperations were necessary in 9 hips (7.6%) due to PJIs in 2, stem loosening in 2, cup loosening in 2, recurrent dislocation in 2, and periprosthetic fracture in 1. No hip had measurable wear or osteolysis. The average mHHS improved from 53.3 points before the revision to 82.3 points at the final follow-up. Survivorship was 91.6% (95% confidence interval, 86.3%–96.9%) at 12 years. Conclusions The Delta ceramic bearing appeared a reliable option for revision THA, showing encouraging mid-term results with acceptable survivorship and a low complication rate.

Gastric cancer is one of the most common cancers in Korea and the world. Since 2004, this is the 4th gastric cancer guideline published in Korea which is the revised version of previous evidence-based approach in 2018. Current guideline is a collaborative work of the interdisciplinary working group including experts in the field of gastric surgery, gastroenterology, endoscopy, medical oncology, abdominal radiology, pathology, nuclear medicine, radiation oncology and guideline development methodology. Total of 33 key questions were updated or proposed after a collaborative review by the working group and 40 statements were developed according to the systematic review using the MEDLINE, Embase, Cochrane Library and KoreaMed database. The level of evidence and the grading of recommendations were categorized according to the Grading of Recommendations, Assessment, Development and Evaluation proposition. Evidence level, benefit, harm, and clinical applicability was considered as the significant factors for recommendation. The working group reviewed recommendations and discussed for consensus. In the earlier part, general consideration discusses screening, diagnosis and staging of endoscopy, pathology, radiology, and nuclear medicine. Flowchart is depicted with statements which is supported by meta-analysis and references. Since clinical trial and systematic review was not suitable for postoperative oncologic and nutritional follow-up, working group agreed to conduct a nationwide survey investigating the clinical practice of all tertiary or general hospitals in Korea. The purpose of this survey was to provide baseline information on follow up. Herein we present a multidisciplinary-evidence based gastric cancer guideline.

Purpose: Convolutional neural networks (CNNs) have rapidly emerged as one of the most promising artificial intelligence methods in the field of medical and dental research. CNNs can provide an effective diagnostic methodology allowing for the detection of early-staged diseases. Therefore, this study aimed to evaluate the performance of a deep CNN algorithm for apical lesion segmentation from panoramic radiographs. Materials and Methods: A total of 1000 panoramic images showing apical lesions were separated into training (n=800, 80%), validation (n=100, 10%), and test (n=100, 10%) datasets. The performance of identifying apical lesions was evaluated by calculating the precision, recall, and F1-score. Results: In the test group of 180 apical lesions, 147 lesions were segmented from panoramic radiographs with an intersection over union (IoU) threshold of 0.3. The F1-score values, as a measure of performance, were 0.828, 0.815, and 0.742, respectively, with IoU thresholds of 0.3, 0.4, and 0.5. Conclusion This study showed the potential utility of a deep learning-guided approach for the segmentation of apical lesions. The deep CNN algorithm using U-Net demonstrated considerably high performance in detecting apical lesions.

Purpose: The purpose of this study was to examine the associations of aerobic physical activity and musclestrengthening exercise with mental health, respectively. Furthermore, the relationship between combined exercise with depression, stress, and suicidal thoughts was also examined. Methods: The association between adherence to physical activity guidelines and mental health was analyzed among 27,268 adults who participated in the 2014– 2018 Korea National Health and Nutrition Examination Survey. Logistic regression was used to predict the relationship between adherence to physical activity guidelines and mental health. Results: The odds ratio for depression and suicidal thoughts in groups that met both aerobic physical activity and muscle-strengthening exercise guidelines decreased by 27% (95% confidence interval [CI], 0.56– 0.94) and 40% (95% CI, 0.39– 0.93), respectively, compared to those that did not meet both. Stress awareness decreased by 22% (95% CI, 0.67– 0.90) in those who met muscular exercise guidelines, but did not meet aerobic physical activity guidelines. For those who met only the aerobic physical activity guidelines, stress awareness decreased by 12% (95% CI, 0.82 – 0.95). In addition, the odds ratio decreased by 29% (95% CI, 0.62 – 0.80) in groups that met both guidelines. Conclusion The most positive relationships between adherence to physical activity guidelines and mental health were found when both aerobic and muscular exercise guidelines were met.