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Abstract Anticancer drugs may affect the incidence of dementia by modulating the common pathophysiology between cancer and dementia. However, there is a paucity of research that focused on anticancer drugs with different mechanisms of action and their associations with subtypes of dementia. Therefore, we aimed to investigate the incidence of dementia according to various groups of anticancer drugs. From the Korea National Health Insurance Service database, our retrospective population-based cohort study enrolled 116,506 cancer patients aged 65 years and older who received anticancer drugs between January 1, 2008 and December 31, 2018. The hazard ratio was determined using Cox proportional hazards regression models, comparing each group of anticancer drugs to all other anticancer drugs, after adjusting for covariates. Antimetabolites (HR = 0.91; 95% CI 0.84–0.97) and molecular targeted therapies (HR = 0.60; 95% CI 0.49–0.74) were associated with a decreased incidence of dementia of the Alzheimer type (DAT), but not with vascular dementia. Among molecular targeted therapies, epidermal growth factor receptor inhibitors (HR = 0.60; 95% CI 0.46–0.79) and multikinase inhibitors (HR = 0.49; 95% CI 0.27–0.89) were associated with a low incidence of DAT only. Our findings highlight the potential for targeted repurposing of anticancer drugs to prevent dementia.

Objective To assess the influence of advanced maternal age on congenital malformations, short- and long-term outcomes in offspring of nulligravida. Methods A retrospective study was conducted using the Korean National Health Insurance Service database spanning from January 2005 to December 2019. All live-born offspring of nulligravida (n=3,685,817) were included. The maternal age was subdivided into the following subgroups: 44 years (n=9,296). Outcomes were assessed based on International Classification of Diseases-10 codes. Adjusted odds ratios (aOR) were calculated with the group of 25-29 years as a reference. Result Most congenital malformations showed an age dependent increase, but cleft lip and abdominal wall defect exhibited a U-shape curve, indicating an increase even in those 44 years old and 1.18 (95% CI, 1.11-1.25) and 1.19 (95% CI, 1.09-1.30) in

Background Continuous renal replacement therapy (CRRT) has become the standard modality of renal replacement therapy (RRT) in critically ill patients. However, consensus is lacking regarding the criteria for discontinuing CRRT. Here we validated the usefulness of the prediction model for successful discontinuation of CRRT in a multicenter retrospective cohort. Methods One temporal cohort and four external cohorts included 1,517 patients with acute kidney injury who underwent CRRT for >2 days from 2018 to 2020. The model was composed of four variables: urine output, blood urea nitrogen, serum potassium, and mean arterial pressure. Successful discontinuation of CRRT was defined as the absence of an RRT requirement for 7 days thereafter. Results The area under the receiver operating characteristic curve (AUROC) was 0.74 (95% confidence interval, 0.71–0.76). The probabilities of successful discontinuation were approximately 17%, 35%, and 70% in the low-score, intermediate-score, and high-score groups, respectively. The model performance was good in four cohorts (AUROC, 0.73–0.75) but poor in one cohort (AUROC, 0.56). In one cohort with poor performance, attending physicians primarily controlled CRRT prescription and discontinuation, while in the other four cohorts, nephrologists determined all important steps in CRRT operation, including screening for CRRT discontinuation. Conclusion The overall performance of our prediction model using four simple variables for successful discontinuation of CRRT was good, except for one cohort where nephrologists did not actively engage in CRRT operation. These results suggest the need for active engagement of nephrologists and protocolized management for CRRT discontinuation.

Abstract Background The cancer experienced in adolescent and young adult (AYA) could disturb developmental changes and long-term life. The current AYA guidelines and research for survivorship were developed and reported according to the general age range of 15–39 years; however, expected life events vary by diagnosed age. We aimed to examine the social, psychological, and physical well-being of AYA cancer survivors by age at diagnosis using a multinational representative dataset focusing on age at diagnosis. Methods We conducted a cross-sectional study using the US and Korean National Health and Nutrition Examination Surveys from 2007 to 2018. Participants diagnosed with any cancer aged 15–39 years and were aged > 18 years at the survey year were defined as AYA cancer survivors. AYA were classified into three groups based on their diagnosed age: adolescent survivors (diagnosed between the ages of 15 and 19, n = 45), young adult survivors (diagnosed between the ages of 20 and 29, n = 238), and late young adult survivors (diagnosed between the ages of 30 and 39, n = 539). We also selected an age-, sex-, race-, and survey year-matched general population with 1:5 ratio among participants without cancer (N = 4110). Results The average age of the survey was 29.1, 43.7, and 48.7 years for AYA survivors diagnosed during adolescence, young adulthood, and late young adulthood, respectively. Adolescent survivors had more non-couple marital status (adjusted odds ratio (aOR), 1.34; 95% CI, 1.10–1.64) and unemployed (aOR, 1.30; 95% CI, 1.05–1.61) compared to late young adult survivors. Comparing with the matched general, adolescent survivors were more in poor general health (aOR, 4.65; 95% CI, 2.09–10.38) and unemployed (aOR, 2.17; 95% CI, 1.12–4.24) and late young adult survivors were more non-couple (aOR, 1.40; 95% CI, 1.05–1.86). Conclusion This study provides evidence for future studies on long-term health, which may vary according to age at the time of diagnosis among AYA with cancer.

Introduction: Understanding human differences is essential for managing chronic diseases. To establish robust evidence for Eight Constitution Medicine (ECM), a Korean personalized medical system, it is necessary to identify the status of clinical research in ECM and develop validated measurements. This study aims to confirm the types of clinical research on ECM and how they have been conducted. Methods: A scoping review covered three international databases (PubMed, Embase, and Cochrane) and five domestic electronic databases (DataBase Periodical Information Academic, Research Information Sharing Service, Korean Studies Information Service System, National Digital Science Library, and Oriental Medicine Advanced Searching for Integrated System), using strategies such as reference searches and gray literature searches. Mapping was attempted, and subcategories were established, synthesized, and presented in tables. All relevant content in Korean and English was considered, excluding theses, dissertations, and editorials. Results: Sixty ECM studies were selected. There were 47 (78.3%) original studies, of which 39 (65.0%) were observational and eight (13.3%) were experimental. There were six eight constitution diet (ECD)-related studies (12.8%), much less than the 15 (31.9%) eight constitution acupuncture (ECA)-related studies. Original studies that measured the effectiveness of ECM used various methods of exposure/intervention and outcome measurement tools. Conclusions: The original research evidence for ECM mainly came from observational studies on ECA and eight constitution diagnosis. Active clinical research related to ECD and a tool that effectively measures adherence and target diseases are required. Furthermore, it is necessary to introduce electronic patient-reported outcome measurements that can be used in community-based clinical environments.

Introduction There is a lack of evidence to support the effectiveness of prolonged β-blocker therapy after stabilisation of patients with acute myocardial infarction (AMI) without heart failure (HF) or left ventricular systolic dysfunction.Methods and analysis The SMart Angioplasty Research Team: DEcision on Medical Therapy in Patients with Coronary Artery DIsease or Structural Heart Disease Undergoing InterventiON (SMART-DECISION) trial is a multicentre, prospective, open-label, randomised, non-inferiority trial designed to determine whether discontinuing β-blocker therapy after ≥1 year of maintenance in stabilised patients after AMI is non-inferior to continuing it. Patients eligible for participation are those without HF or left ventricular systolic dysfunction (ejection fraction >40%) who have been continuing β-blocker therapy for ≥1 year after AMI. A total of 2540 patients will be randomised 1:1 to continuation of β-blocker therapy or not. Randomisation will be stratified according to the type of AMI (ie, ST-segment-elevation MI or non-ST-segment-elevation MI), type of β-blocker (carvedilol, bisoprolol, nebivolol or other) and participating centre. The primary study endpoint is a composite of all-cause death, MI and hospitalisation for HF over a median follow-up period of 3.5 years (minimum, 2.5 years; maximum, 4.5 years). Adverse effects related to β-blocker therapy, the occurrence of atrial fibrillation, medical costs and Patient-reported Outcomes Measurement Information system-29 questionnaire responses will also be collected as secondary endpoints.Ethics and dissemination Ethics approval for this study was granted by the Institutional Review Board of Samsung Medical Center (no. 2020-10-176). Informed consent is obtained from every participant before randomisation. The results of this study will be submitted for publication in international peer-reviewed journals and the key findings will be presented at international scientific conferences.Trial registration number ClinicalTrials.gov, NCT04769362.

Abstract Objective Although breast magnetic resonance imaging (MRI) is a valuable screening tool, breast MRI testing burden was associated with cancer worry and quality of life. We aimed to develop and validate the MRI‐related distress scale (MRI‐DS) to assess comprehensive distress specifically related to breast MRI. Methods We enrolled women aged above 18 years, diagnosed breast cancer, had MRI examination at least one time, and who could speak and read Korean in phase I and enrolled women aged above 18 years, visited outpatient clinic of breast general surgery, had undergone MRI examination at least once, and could speak and read Korean in phase II. We excluded patients who had any physical or psychiatric conditions in both phases. We recruited from a tertiary university‐based hospital in South Korea between April and August 2023. Results All 18 items had acceptable levels of item correlation (≥0.30) in the explanatory factor analysis with a four‐factor solution. The fit indices for the four‐factor solution model were good. The discriminant validity of the MRI‐DS had a moderate correlation with general anxiety or quality of life. In the known‐group analysis, those who reported MRI as the most burden breast examination had higher total scores. Conclusion The validity of the MRI‐DS has been confirmed as a scale for measuring the specific distress caused by breast MRI. The MRI‐DS is recommended to health professional to communicate with patients with MRI. Clinical Implications It can be used to assess the distress associated with MRI screening in breast cancer patients. Physician could use MRI‐DS to discuss the reasons for distress caused by breast MRI screening and to address specific sources of discomfort associated with it.

Abstract Background The association between longitudinal body mass index (BMI) change and clinical outcomes in patients with chronic obstructive pulmonary disease (COPD) has not fully investigated. Methods This retrospective cohort study included 116,463 COPD patients aged ≥ 40, with at least two health examinations, one within 2 years before and another within 3 years after COPD diagnosis (January 1, 2014, to December 31, 2019). Associations between BMI percentage change with all-cause mortality, primary endpoint, and initial severe exacerbation were assessed. Results BMI decreased > 5% in 14,728 (12.6%), while maintained in 80,689 (69.2%), and increased > 5% in 21,046 (18.1%) after COPD diagnosis. Compared to maintenance group, adjusted hazard ratio (aHR) for all-cause mortality was 1.70 in BMI decrease group (95% CI:1.61, 1.79) and 1.13 in BMI increase group (95% CI:1.07, 1.20). In subgroup analysis, decrease in BMI showed a stronger effect on mortality as baseline BMI was lower, while an increase in BMI was related to an increase in mortality only in obese COPD patients with aHRs of 1.18 (95% CI: 1.03, 1.36). The aHRs for the risk of severe exacerbation (BMI decrease group and increase group vs. maintenance group) were 1.30 (95% CI:1.24, 1.35) and 1.12 (95% CI:1.07, 1.16), respectively. Conclusions A decrease in BMI was associated with an increased risk of all-cause mortality in a dose-dependent manner in patients with COPD. This was most significant in underweight patients. Regular monitoring for weight loss might be an important component for COPD management.

Abstract Anemia is common in critically ill patients undergoing continuous renal replacement therapy (CRRT). We investigated the impact of anemia requiring red blood cell (RBC) transfusion or erythropoiesis-stimulating agents (ESAs) on patient outcomes after hospital discharge in critically ill patients with acute kidney injury (AKI) requiring CRRT. In this retrospective cohort study using the Health Insurance Review and Assessment database of South Korea, 10,923 adult patients who received CRRT for 3 days or more between 2010 and 2019 and discharged alive were included. Anemia was defined as the need for RBC transfusion or ESAs. Outcomes included cardiovascular events (CVEs) and all-cause mortality after discharge. The anemia group showed a tendency to be older with more females and had more comorbidities compared to the control group. Anemia was not associated with an increased risk of CVEs (adjusted hazard ratio [aHR]: 1.05; 95% confidence interval [CI]: 0.85–1.29), but was associated with an increased risk of all-cause mortality (aHR: 1.41; 95% CI 1.30–1.53). For critically ill patients with AKI requiring CRRT, anemia, defined as requirement for RBC transfusion or ESAs, may increase the long-term risk of all-cause mortality.

Abstract Background The effects of smoking reduction on the incidence of lung cancer in patients with chronic obstructive pulmonary disease (COPD) are not well known. This study aimed to investigate the effects of changes in smoking habits after COPD diagnosis on lung cancer development in patients who smoked less than 30 pack-years. Methods This nationwide retrospective cohort study included 16,832 patients with COPD who smoked less than 30 pack-years at the time of COPD diagnosis. Based on changes in smoking habits in the health screening examination data, smokers were categorized into three groups: quitters, reducers, and sustainers. The primary outcome was the risk of lung cancer development, which was estimated using the Cox proportional hazards model. We also modelled the amount of smoking reduction as a continuous variable. Results During a median follow-up of 4 years, the cumulative incidence of lung cancer was the highest among sustainers, followed by reducers and quitters. Compared with sustainers, reducers (adjusted HR 0.74, 95% CI:0.56–0.98) and quitters (adjusted HR 0.78, 95% CI:0.64–0.96) had a significantly lower risk of lung cancer. Incidence of lung cancer showed a decreasing trend with a decreasing amount of smoking (P for linearity

Abstract Limited information is available regarding the association between preoperative lung function and postoperative pulmonary complications (PPCs) in patients with esophageal cancer who undergo esophagectomy. This is a retrospective cohort study. Patients were classified into low and high lung function groups by the cutoff of the lowest fifth quintile of forced expiratory volume in 1 s (FEV1) %predicted (%pred) and diffusing capacity of the carbon monoxide (DLco) %pred. The PPCs compromised of atelectasis requiring bronchoscopic intervention, pneumonia, and acute lung injury/acute respiratory distress syndrome. Modified multivariable-adjusted Poisson regression model using robust error variances and inverse probability treatment weighting (IPTW) were used to assess the relative risk (RR) for the PPCs. A joint effect model considered FEV1%pred and DLco %pred together for the estimation of RR for the PPCs. Of 810 patients with esophageal cancer who underwent esophagectomy, 159 (19.6%) developed PPCs. The adjusted RR for PPCs in the low FEV1 group relative to high FEV1 group was 1.48 (95% confidence interval [CI] = 1.09–2.00) and 1.98 (95% CI = 1.46–2.68) in the low DLco group relative to the high DLco group. A joint effect model showed adjusted RR of PPCs was highest in patients with low DLco and low FEV1 followed by low DLco and high FEV1, high DLco and low FEV1, and high DLco and high FEV1 (Reference). Results were consistent with the IPTW. Reduced preoperative lung function (FEV1 and DLco) is associated with post-esophagectomy PPCs. The risk was further strengthened when both values decreased together.

Introduction Symptoms due to chemotherapy are common in patients with cancer. Cancer-related symptoms are closely associated with the deterioration of physical function which can be associated with decreased quality of life and increased mortality. Thus, timely symptom identification is critical for improving cancer prognosis and survival. Recently, remote symptom monitoring system using digital technology has demonstrated its effects on symptom control or survival. However, few studies examined whether remote monitoring would contribute to retaining physical function among patients with cancer. Therefore, this study aimed to evaluate the effectiveness of mobile-based symptom monitoring in improving physical function among patients with cancer under chemotherapy.Methods and analysis This study is a multicentre, open-label, parallel-group, randomised controlled trial. We will recruit 372 patients at three tertiary hospitals located in Seoul, South Korea. Study participants will be randomly assigned to either an intervention group receiving the ePRO-CTCAE app and a control group receiving routine clinical practice only. The primary outcome is changes in physical function from commencement to completion of planned chemotherapy. A linear mixed model will be performed under the intention-to-treat principle. The secondary outcomes include physical activity level; changes in pain interference; changes in depressive symptom; unplanned clinical visits; additional medical expenditure for symptom management; completion rate of planned chemotherapy; changes in symptom burden and health-related quality of life; and 1-year overall mortality.Ethics and dissemination The study has been approved by the institutional review board and ethics committee at the three university hospitals involved in this trial. Written informed consent will be obtained from all the participants. The results of the trial will be submitted for publication in peer-reviewed academic journals and disseminated through relevant literatures.Trial registration number KCT0007220.

Abstract Objective To evaluate a psychometric validation of the endometrial cancer subscales (EnCS) in the Functional Assessment of Cancer Therapy‐Endometrial (FACT‐EN) among patients with endometrial cancer. Methods This cross‐sectional study was conducted at a tertiary university‐based hospital in South Korea between April and October 2022. Participants completed a survey questionnaire that included the FACT‐EN. Exploratory and confirmatory factor analyses (EFA, CFA) and the reliability were measured using the intraclass correlation coefficient (ICC) under a two‐way mixed model. Pearson's correlations were used to evaluate the validity. We also tested known‐group validity. Results In total, 240 patients with endometrial cancer participated in the survey. In EFA, we found EnCS included four domains. In CFA, four‐factor solution model was good: CFI = 0.659; SRMR = 0.066, and RMSEA = 0.073. The mean (SD) of total score of FACT‐EN was 122.84 (23.58). The floor and ceiling effects were 0.4% and 0.4%, respectively. Cronbach's α coefficients for the five scales of the EnCS ranged from 0.78 to 0.91. The ICC of EnCS was 0.76. The convergent and discriminant validity of EnCS was acceptable. In the group analysis, older age and lower ECOG performance scores were associated with higher EnCS scores. The stomach and vaginal domains in EnCS were higher in patients who had completed treatment for more than 1 year compared to those who were still undergoing treatment. Conclusions FACT‐EN has demonstrated its validity as an assessment tool with significant implications for capturing various symptoms in patients with endometrial cancer.

BackgroundLung cancer diagnosis affects an individual’s quality of life as well as physical and emotional functioning. Information on survivorship care tends to be introduced at the end of treatment, but early intervention may affect posttreatment adjustment. However, to the best of our knowledge, no study has explored the effect of early information intervention on the return to work, family, and societal roles of lung cancer survivors. ObjectiveWe report the study protocol of a comprehensive care prehabilitation intervention designed to facilitate lung cancer survivors’ psychological adjustment after treatment. MethodsA comprehensive care program was developed based on a literature review and a qualitative study of patients with lung cancer and health professionals. The Lung Cancer Comprehensive Care Program consists of educational videos and follow-up visits by a family medicine physician. To prevent contamination, the control group received routine education, whereas the intervention group received routine care and intervention. Both groups completed questionnaires before surgery (T0) and at 1-month (T1), 6-month (T2), and 1-year (T3) follow-up visits after surgery. The primary outcome was survivors’ psychological adjustment to cancer 6 months after pulmonary resection. ResultsThe historical control group (n=441) was recruited from September 8, 2021, to April 20, 2022, and the intervention group (n=350) was recruited from April 22, 2022, to October 17, 2022. All statistical analyses will be performed upon completion of the study. ConclusionsThis study examined the effectiveness of an intervention that provided general and tailored informational support to lung cancer survivors, ranging from before to the end of treatment. Trial RegistrationClinicalTrials.gov NCT05078918; https://clinicaltrials.gov/ct2/show/NCT05078918 International Registered Report Identifier (IRRID)DERR1-10.2196/54707

Background & aimsA new nomenclature, Steatotic Liver Disease (SLD), has been proposed by consensus with sub-classifications and requires evidence-based validation. We assessed whether the presence and severity of SLD, as well as its sub-classifications, are associated with the progression of coronary atherosclerosis.MethodsThis longitudinal cohort study included 13,811 adults who participated in repeated regular health screening examinations between January 1, 2004 and December 31, 2021 that included assessments of their coronary artery calcium (CAC) scores. SLD was defined using abdominal ultrasonography and classified as metabolic dysfunction associated steatotic liver disease (MASLD), MASLD with increased alcohol intake (MetALD), and cryptogenic SLD. SLD severity was assessed using fibrosis-4 (FIB-4) scores. The progression of CAC scores was measured using multidetector CT scans.ResultsThe average duration of follow-up was 5.8 years. During follow-up, the annual rate of CAC progression in participants with and without SLD was 18% (95% CI 17%-19%) and 14% (95% CI 13%-14%) (p < 0.01), respectively. The multivariable ratios of progression rates when we compared participants with cryptogenic SLD, MASLD, or MetALD with those without SLD were 0.98 (95% CI 0.95-1.01), 1.03 (95% CI 1.03-1.04), and 1.07 (95% CI 1.04-1.09), respectively. The multivariable ratios of progression rates when we compared participants with SLD with FIB-4 score ConclusionsSLD was associated with a higher risk of coronary atherosclerosis, and the risk differed by sub-classifications and severity. These findings suggest that the newly proposed definition has clinical relevance in terms of stratifying cardiovascular disease risk.

Background Preserved ratio impaired spirometry (PRISm) is associated with increased cardiovascular disease (CVD) risk and mortality. However, a causal relationship between PRISm and CVD remains unclear. We investigated the progression of coronary artery calcium (CAC) scores based on the presence of PRISm and reduced forced vital capacity (FVC). Methods This retrospective cohort study included 11 420 participants aged ≥40 years with forced expiratory volume in 1 s (FEV1)/FVC ≥0.7 who underwent at least two health screening examinations with coronary computed tomography scan between 2003 and 2020, and were without a history of CVD or interstitial lung disease. Participants with PRISm, defined as FEV1/FVC ≥0.7 and FEV1

Olive leaf contains plenty of phenolic compounds, among which oleuropein (OP) is the main component and belongs to the group of secoiridoids. Additionally, phenolic compounds such as oleocanthal (OL) and oleacein (OC), which share a structural similarity with OP and two aldehyde groups, are also present in olive leaves. These compounds have been studied for several health benefits, such as anti-cancer and antioxidant effects. However, their impact on the skin remains unknown. Therefore, this study aims to compare the effects of these three compounds on melanogenesis using B16F10 cells and human epidermal cells. Thousands of gene expressions were measured by global gene expression profiling with B16F10 cells. We found that glutaraldehyde compounds derived from olive leaves have a potential effect on the activation of the melanogenesis pathway and inducing differentiation in B16F10 cells. Accordingly, the pro-melanogenesis effect was investigated by means of melanin quantification, mRNA, and protein expression using human epidermal melanocytes (HEM). This study suggests that secoiridoid and its derivates have an impact on skin protection by promoting melanin production in both human and mouse cell lines.

Purpose We evaluated the association between changes in social support after cancer treatment and recurrence-free survival (RFS) in such patients using a prospective cohort study. Materials and Methods Data were obtained from a prospective cohort study (NCT03131089) conducted at Samsung Medical Center (2013-2021). The primary outcome measure was RFS. Social support was measured using the social and family well-being (SFWB) domain of the Functional Assessment of Cancer Therapy-General. We calculated the changes in SFWB scores before and during treatment and the hazard ratio for RFS by comparing such changes. Results The mean±standard deviation (SD) age of the patients was 35±3.9 years, and 71.5% and 64.8% of the patients were married and had children, respectively. The mean±SD SFWB score at baseline was 20.5±5.0 out of 26. After cancer treatment, 35.9%, 10.3%, and 53.8% of the participants had increasing, unchanged, and decreasing SFWB scores, respectively. The decreasing SFWB score group had a higher risk of mortality or recurrence than the increasing group. Risk factors for the decreasing score were the presence of children during diagnosis. Conclusion In this cohort, changes in social support after treatment were associated with RFS in young patients with breast cancer. Health professionals should develop family interventions to help them receive proper social support. [ABSTRACT FROM AUTHOR]

For the secure deployment of network platforms tailored for IoT devices, the encryption of data transmission is equally as crucial as the process of authentication. In this context, we introduce the Secure and Scalable IoT network (SSI) network platform, designed to accommodate a diverse range of IoT devices. It provides scalability and implements effective many-to-many and end-to-end encryption across extensive regions. With the emergence of quantum computing, secure public key exchange mechanisms have become important. Among the various post-quantum cryptography (PQC) algorithms assessed, Nth Degree Truncated Polynomial Ring Units (NTRUs) have emerged as an optimally suited PQC algorithm for IoT devices constrained by limited computational capabilities. We have integrated NTRUs with SSI as a lightweight PQC solution. Moreover, SSI-PQM (Post-Quantum MACsec) enhances the SSI’s initial authentication structure to minimize PQC-TLS session attempts and protect the SSI’s important configuration information. When applying TLS with PQC for secret key exchange purposes, it was verified that this approach ensures stable performance in IoT environments. Upon the implementation of our proposed SSI-PQM on Raspberry Pi 3B+ based IoT devices, SSI-PQM exhibited acceptable performance at security levels from 80 to 128 and achieved a minimum speed improvement of 161% over RSA at security levels above 160. It can be concluded that SSI-PQM stands out as an effective Zero Trust-based IoT network platform, demonstrating its viability and efficiency in safeguarding data transmission against potential quantum computing threats.