Purpose: Postoperative complications following gastric cancer surgery significantly impact patient outcomes, yet standardized definitions for these events have not been consistently applied across institutions in Korea. This study aimed to develop a consensus-based, standardized complication classification system specific to gastrectomy for gastric cancer as part of the Korean Quality Improvement Platform in Surgery (K-QIPS) initiative. Methods: As part of K-QIPS, a dedicated task force team (TFT) was formed with surgical experts from fourteen high-volume hospitals across Korea. The TFT conducted ten formal meetings to review existing literature and international guidelines, and incorporated findings from randomized controlled trials. The final complication list was developed through expert consensus and structured into a standardized framework. A Data Entry Manual was created to support consistent data collection by surgical clinical reviewers. Results: The TFT defined specific postoperative complications following gastrectomy for gastric cancer, including anastomotic leakage, duodenal stump leakage, pancreatic fistula, intra-abdominal and luminal bleeding, delayed gastric emptying, and internal hernia. Notably, internal hernia was described in standardized form for the first time. General complications were developed first and overlapped in part with the gastric cancer-specific list. The task force also produced a Data Entry Manual that provides practical instructions to ensure consistency and accuracy in complication reporting. Conclusion This nationwide consensus initiative established the first standardized complication classification system for gastric cancer surgery in Korea. The proposed definitions and data entry system are expected to improve complication reporting, enable multicenter research, support surgical quality benchmarking, and ultimately enhance patient outcomes.

The usefulness of the living kidney donor profile index (LKDPI) has not been widely demonstrated; therefore, it requires verification before clinical application. We analyzed the LKDPI using data from the Korean Organ Transplantation Registry (KOTRY) to confirm whether the LKDPI can be used to predict the survival of allografts in living donor kidney transplantation (LDKT) patients in Korea. Methods: The study population was obtained from the KOTRY database. A total of 2,598 kidney recipients registered in the KOTRY database were enrolled between May 2014 and December 2020. Donor and recipient information was observed, and the LKDPI was measured. Results: Median LKDPI score was 15.5 with a follow-up duration of 33.7 ± 16.1 months. According to LKDPI scores (group 1, <0; group 2, 0–20; group 3, 20–40; and group 4, >40), LKDPI group 4 had significantly higher death-censored graft loss than LKDPI group 1 (hazard ratio [HR], 1.89; 95% confidence interval [CI], 1.06– 3.40; p = 0.03). When divided based on the cutoff value (LKDPI, 36.6), the high LKDPI group had higher graft loss than the low LKDPI group (HR, 2.14; 95% CI, 1.37–3.34; p < 0.001). When follow-up was repeated after transplantation, it was confirmed that the higher the LKDPI value was, the lower the average estimated glomerular filtration rate (p < 0.001). Conclusion: This study confirmed that LKDPI can serve as an independent predictor for assessing the risk of allograft failure and transplant outcomes in Korean LDKT patients.

Background/Aims: This study compared the effectiveness and safety of glecaprevir/pibrentasvir (GLE/PIB) and sofosbuvir/ledipasvir (SOF/LDV) in real-life clinical practice. Methods: The data from genotype 1 or 2 chronic hepatitis C patients treated with GLE/PIB or sofosbuvir + ribavirin or SOF/LDV in South Korea were collected retrospectively. The analysis included the treatment completion rate, sustained virologic response at 12 weeks (SVR12) test rate, treatment effectiveness, and adverse events. Results: Seven hundred and eighty-two patients with genotype 1 or 2 chronic hepatitis C who were treated with GLE/PIB (n=575) or SOF/LDV (n=207) were included in this retrospective study. The baseline demographic and clinical characteristics revealed significant statistical differences in age, genotype, ascites, liver cirrhosis, and hepatocellular carcinoma between the GLE/PIB and SOF/LDV groups. Twenty-two patients did not complete the treatment protocol. The treatment completion rate was high for both regimens without statistical significance (97.7% vs. 95.7%, p=0.08). The overall SVR12 of intention-to-treat analysis was 81.2% vs. 80.7% without statistical significance (p=0.87). The overall SVR12 of per protocol analysis was 98.7% vs. 100% without statistical significance (p=0.14). Six patients treated with GLE/PIB experienced treatment failure. They were all male, genotype 2, and showed a negative hepatitis C virus RNA level at the end of treatment. Two patients treated with GLE/PIB stopped medication because of fever and abdominal discomfort. Conclusions Both regimens had similar treatment completion rates, effectiveness, and safety profiles. Therefore, the SOF/LDV regimen can also be considered a viable DAA for the treatment of patients with genotype 1 or 2 chronic hepatitis C.

Background: Coronavirus disease 2019 (COVID-19) is often accompanied by secondary infections, such as invasive aspergillosis. In this study, risk factors for developing COVID-19-associated pulmonary aspergillosis (CAPA) and their clinical outcomes were evaluated. Methods: This multicenter retrospective cohort study included critically ill COVID-19 patients from July 2020 through March 2021. Critically ill patients were defined as patients requiring high-flow respiratory support or mechanical ventilation. CAPA was defined based on the 2020 European Confederation of Medical Mycology and the International Society for Human and Animal Mycology consensus criteria. Factors associated with CAPA were analyzed, and their clinical outcomes were adjusted by a propensity score-matched model. Results: Among 187 eligible patients, 17 (9.1%) developed CAPA, which is equal to 33.10 per 10,000 patient-days. Sixteen patients received voriconazole-based antifungal treatment. In addition, 82.4% and 53.5% of patients with CAPA and without CAPA, respectively, received early high-dose corticosteroids (P = 0.022). In multivariable analysis, initial 10-day cumulative steroid dose > 60 mg of dexamethasone or dexamethasone equivalent dose) (adjusted odds ratio [OR], 3.77; 95% confidence interval [CI], 1.03–13.79) and chronic pulmonary disease (adjusted OR, 4.20; 95% CI, 1.26–14.02) were independently associated with CAPA. Tendencies of higher 90-day overall mortality (54.3% vs. 35.2%, P= 0.346) and lower respiratory support-free rate were observed in patients with CAPA (76.3% vs. 54.9%, P = 0.089). Conclusion Our study showed that the dose of corticosteroid use might be a risk factor for CAPA development and the possibility of CAPA contributing to adverse outcomes in critically ill COVID-19 patients.

The objective of this study was to fabricate Zr-xCu and Zr-xSi alloys with low elastic modulus for preventing bone resorption in dental biomaterials. Metallic materials are widely used for orthopedic and dental applications due to their superior characteristics of mechanical properties and biocompatibility. Many metals and alloys, such as stainless steel, Co-Cr alloys, and Ti-based alloys are commonly used. Among these dental metallic materials, pure Ti and Ti-6Al-4V alloy have become the most popular metals used for the endosseous parts of the implant, bone plates, and artificial joints due to their excellent specific corrosion resistance and high biocompatibility with natural bone. Stress shield effect results in the reduction in bone density as a result of the removal of typical stress from the bone by an implant. In general, the bone in a healthy person will remodel in response to the loads it is placed under. Therefore, if the loading on a bone decreases, the bone will become less dense and weaker because there is no stimulus for continued remodeling that is required to maintain bone mass. Although Ti-based alloys have been widely used as implant components and devices, its elastic modulus (110 GPa) is much higher than that of natural human bone (10–30 GPa). Serious damage may be easily caused in the human body when the modulus of implant materials does not match the natural bone due to the stress shield effects. Therefore, in recent, persistent efforts have been done to obtain biological hard tissue materials with low elastic modulus to transfer stress to the surrounding bones effectively. The Zr-xCu binary alloy exhibited moderate compressive strength (1291-1411 MPa), yield stress (517-552 MPa), favorable elongation (16.4–49.2%), elastic energy (6.76–7.43 MJ/m3 ) and low elastic modulus (18.5–23.1 GPa). The Zr-xSi binary alloy exhibited high compressive strength (1105-1623 MPa), yield stress (673-1514 MPa), favorable elongation (6.0–27.2%), high elastic energy (10.2–34.6 MJ/m3 ) and low elastic modulus (22.3–33.1 GPa). Consequently, Zr-xCu and Zr-xSi binary alloys have the potential to be used as biomaterials with nullifying stress shield effects for biological hard tissue materials.

The objective of this study was to fabricate Zr-xCu and Zr-xSi alloys with low elastic modulus for preventing bone resorption in dental biomaterials. Metallic materials are widely used for orthopedic and dental applications due to their superior characteristics of mechanical properties and biocompatibility. Many metals and alloys, such as stainless steel, Co-Cr alloys, and Ti-based alloys are commonly used. Among these dental metallic materials, pure Ti and Ti-6Al-4V alloy have become the most popular metals used for the endosseous parts of the implant, bone plates, and artificial joints due to their excellent specific corrosion resistance and high biocompatibility with natural bone. Stress shield effect results in the reduction in bone density as a result of the removal of typical stress from the bone by an implant. In general, the bone in a healthy person will remodel in response to the loads it is placed under. Therefore, if the loading on a bone decreases, the bone will become less dense and weaker because there is no stimulus for continued remodeling that is required to maintain bone mass. Although Ti-based alloys have been widely used as implant components and devices, its elastic modulus (110 GPa) is much higher than that of natural human bone (10–30 GPa). Serious damage may be easily caused in the human body when the modulus of implant materials does not match the natural bone due to the stress shield effects. Therefore, in recent, persistent efforts have been done to obtain biological hard tissue materials with low elastic modulus to transfer stress to the surrounding bones effectively. The Zr-xCu binary alloy exhibited moderate compressive strength (1291-1411 MPa), yield stress (517-552 MPa), favorable elongation (16.4–49.2%), elastic energy (6.76–7.43 MJ/m3 ) and low elastic modulus (18.5–23.1 GPa). The Zr-xSi binary alloy exhibited high compressive strength (1105-1623 MPa), yield stress (673-1514 MPa), favorable elongation (6.0–27.2%), high elastic energy (10.2–34.6 MJ/m3 ) and low elastic modulus (22.3–33.1 GPa). Consequently, Zr-xCu and Zr-xSi binary alloys have the potential to be used as biomaterials with nullifying stress shield effects for biological hard tissue materials.

The objective of this study was to fabricate Zr-Cu alloys with low elastic modulus and low magnetic susceptibility for the use as the dental biomaterials. Metallic implants, such as stainless steel, Co-Cr alloys, and Ti alloys, could be magnetized in the strong magnetic field of the MRI instrument and produce artifacts (magnetic susceptibility artifacts) on the image. The areas that cause the artifacts on images are closely related to the magnetic susceptibility. This susceptibility artifact is caused by metals, such as Ti, Co, and stainless steels, inside the body. Therefore, metallic implants with a low magnetic susceptibility are preferable for surgery performed with the assistance of an MRI. Recently, Zr-based alloys have been attracting interests as biomaterials due to their excellent mechanical properties and low magnetic susceptibility. The magnetic susceptibility of Zr-Nb was half that of Ti-6Al-4V. In addition, the magnetic susceptibility of Zr-Mo was reported almost one-third that of commercially pure Ti and Ti-6Al-4V alloy.However, there are limited reports concerning metallic biomaterials with low magnetic susceptibility for dental applications. The magnetic susceptibility of the Zr-Cu binary alloys was extremely low, approximately 10-7 ; this level is approximately one order less than that of pure Zr and other commercialized Ti-based metallic biomaterials. The Zr-Cu binary alloy exhibited moderate compressive strength (1261~1565 MPa), yield stress (432~595 MPa), favorable elongation (14~34%), high elastic energy (7.2~19.3 MJ/㎥ ) and low elastic modulus (20~28 GPa). Consequently, Zr-Cu binary alloys have the potential to be used as biomaterials with nullifying magnetic properties for magnetic resonance imaging diagnosis and a good combination of mechanical properties indicates them potential biomaterials for biological hard tissue materials

The objective of this study was to fabricate Zr-Cu alloys with low elastic modulus and low magnetic susceptibility for the use as the dental biomaterials. Metallic implants, such as stainless steel, Co-Cr alloys, and Ti alloys, could be magnetized in the strong magnetic field of the MRI instrument and produce artifacts (magnetic susceptibility artifacts) on the image. The areas that cause the artifacts on images are closely related to the magnetic susceptibility. This susceptibility artifact is caused by metals, such as Ti, Co, and stainless steels, inside the body. Therefore, metallic implants with a low magnetic susceptibility are preferable for surgery performed with the assistance of an MRI. Recently, Zr-based alloys have been attracting interests as biomaterials due to their excellent mechanical properties and low magnetic susceptibility. The magnetic susceptibility of Zr-Nb was half that of Ti-6Al-4V. In addition, the magnetic susceptibility of Zr-Mo was reported almost one-third that of commercially pure Ti and Ti-6Al-4V alloy.However, there are limited reports concerning metallic biomaterials with low magnetic susceptibility for dental applications. The magnetic susceptibility of the Zr-Cu binary alloys was extremely low, approximately 10-7 ; this level is approximately one order less than that of pure Zr and other commercialized Ti-based metallic biomaterials. The Zr-Cu binary alloy exhibited moderate compressive strength (1261~1565 MPa), yield stress (432~595 MPa), favorable elongation (14~34%), high elastic energy (7.2~19.3 MJ/㎥ ) and low elastic modulus (20~28 GPa). Consequently, Zr-Cu binary alloys have the potential to be used as biomaterials with nullifying magnetic properties for magnetic resonance imaging diagnosis and a good combination of mechanical properties indicates them potential biomaterials for biological hard tissue materials

PURPOSE: The extension of endocrine therapy beyond 5 years for recurrence-free survivors of breast cancer improves survival; however, the issue on how to clinically identify appropriate candidates remains controversial. This study aimed to identify prognostic factors for breast-cancer-specific mortality in patients who have had 5 years of tamoxifen treatment and categorize subgroups based on the risk of death using combinations of these prognostic factors to assist in the clinical decision to perform further endocrine therapy. METHODS: In total, 3,158 patients with breast cancer were enrolled. Breast cancer-specific survival rates after 5 years of tamoxifen treatment were calculated, and associated prognostic factors were analyzed using a Cox proportional-hazards model. RESULTS: An age extreme at diagnosis (i.e., < 40 or ≥ 60 years), tumor size > 2 cm, and positive lymphovascular invasion were robust independent prognostic factors for late breast cancer-specific death in tamoxifen-treated patients (hazard ratio [HR] = 2.162, 1.739, and 1.993; p = 0.001, 0.047, and 0.011, respectively). Lymph node metastasis and progesterone receptor negativity had borderline significance in this regard (HR = 1.741 and 1.638, p = 0.099 and 0.061). The study patients were classified into four groups according to the number of prognostic indicators, i.e., low, intermediate, high, and extremely high risk. The additional 5- and 10-year cumulative risks of breast cancer-specific death were 0.8% and 1.5% in the low-risk group, 0.9% and 3.9% in the intermediate-risk group, 1.3% and 7.3% in the high-risk group, and 4.8% and 13.8% in the extremely high-risk group, respectively. CONCLUSION: This new risk stratification system for late mortality in breast cancer can be used to identify the right candidates for extended endocrine therapy after 5 years of tamoxifen treatment.
Breast Neoplasms ; Breast ; Diagnosis ; Humans ; Lymph Nodes ; Mortality ; Neoplasm Metastasis ; Prognosis ; Receptors, Progesterone ; Survival Rate ; Survivors ; Tamoxifen

PURPOSE: The aim of this study was to determine the effects of patterned human periodontal ligament stem cell (hPDLSC) sheets fabricated using a thermoresponsive substratum. METHODS: In this study, we fabricated patterned hPDLSC sheets using nanotopographical cues to modulate the alignment of the cell sheet. RESULTS: The hPDLSCs showed rapid monolayer formation on various surface pattern widths. Compared to cell sheets grown on flat surfaces, there were no significant differences in cell attachment and growth on the nanopatterned substratum. However, the patterned hPDLSC sheets showed higher periodontal ligamentogenesis-related gene expression in early stages than the unpatterned cell sheets. CONCLUSIONS: This experiment confirmed that patterned cell sheets provide flexibility in designing hPDLSC sheets, and that these stem cell sheets may be candidates for application in periodontal regenerative therapy.
Cues ; Extracellular Matrix ; Gene Expression ; Humans* ; Periodontal Ligament* ; Pliability ; Regeneration ; Stem Cells* ; Tissue Engineering