1.Long-term survival outcomes and prognostic factors following radical resection of pancreatic body and tail cancer:a retrospective analysis of 992 patients
Dong XU ; Yang WU ; Kai ZHANG ; Nan LYU ; Qianqian WANG ; Pengfei WU ; Jie YIN ; Baobao CAI ; Guodong SHI ; Jianzhen LIN ; Yazhou WANG ; Lingdi YIN ; Zipeng LU ; Min TU ; Jianmin CHEN ; Feng GUO ; Jishu WEI ; Junli WU ; Wentao GAO ; Cuncai DAI ; Yi MIAO ; Kuirong JIANG
Chinese Journal of Surgery 2026;64(1):46-54
Objective:To investigate the survival outcomes and prognostic factors in patients undergoing radical resection for pancreatic body and tail cancer.Methods:A retrospective case series study was conducted on 992 patients who underwent radical resection for pancreatic body and tail cancer at the Pancreatic Center of the First Affiliated Hospital of Nanjing Medical University from January 2016 to June 2024. In this study, 577 (58.2%) were male and 415 (41.8%) were female,with an age of (65±9) years (range: 26 to 86 years). Follow-up continued until June 2024. Survival rates were estimated using the Kaplan-Meier method,and prognostic factors were identified using univariate and multivariate Cox proportional hazards models.Results:Among 992 patients,open surgery was the predominant approach (89.1%, 884/992), and radical antegrade modular pancreatosplenectomy (RAMPS) was performed in 317 patients (32.0%). Combined organ resection,venous resection,and arterial resection were performed in 23.5%, 9.3%,and 11.2% of patients,respectively. The rates of R0, R1-1 mm, and R1-direct resections were 49.8% (494/992),41.5% (412/992), and 8.7% (86/992),respectively. Stage ⅡB was the most common TNM stage (32.2%,319/992). A total of 801 patients (80.8%) received adjuvant chemotherapy. The median follow-up period was 32.0(8.8) months(range:3.2 to 105.3 months),during which 508 patients (51.2%) died. The overall median survival (OS) was 26.4 months,with 1-,3-, and 5-year survival rates of 79.0%,40.0%, and 29.0%, respectively. In the recent five years (from 2020 to 2024), the median OS improved significantly to 34.1 months compared to 20.0 months from 2016 to 2019 ( P<0.01). Histological subtype analysis showed that the median OS time was 26.7 months for pancreatic ductal adenocarcinoma (PDAC, n=855),58.9 months for invasive intraductal papillary mucinous carcinoma (IPMC, n=32),and 15.7 months for adenosquamous carcinoma of pancreas (ASCP, n=73) ( P=0.001). Among PDAC patients, adjuvant chemotherapy significantly improved survival (29.1 months vs. 14.4 months, P<0.01);in IPMC patients, adjuvant chemotherapy also extended survival (65.7 months vs. 58.9 months, P=0.047). Although ASCP patients receiving chemotherapy had a longer median OS time than those without (18.8 months vs. 8.9 months),the difference was not statistically significant ( P=0.151). Multivariate Cox regression analysis in PDAC patients indicated that adjuvant chemotherapy, R0 resection, T stage,N stage,and tumor differentiation were independent prognostic factors ( P<0.01). The median OS time by TNM stage was:not reached for stage ⅠA, 51.6 months for ⅠB, 25.5 months for ⅡA, 23.7 months for ⅡB, 23.0 months for Ⅲ, and 14.4 months for Ⅳ. The median OS time for R0,R1-1 mm,and R1-direct resections was 34.1,24.7,and 15.7 months,respectively ( P<0.01). Conclusion:Adjuvant chemotherapy,R0 resection,tumor stage,and differentiation are independent prognostic factors for pancreatic body and tail cancer.
2.Development and validation of PhenoRAG: A visualization tool for automated human phenotype ontology term annotation based on large language models and retrieval-augmented generation technology.
Wei ZHONG ; Yousheng YAN ; Kai YANG ; Yan LIU ; Xinyu FU ; Zhengyang YAO ; Chenghong YIN
Chinese Journal of Medical Genetics 2026;43(1):36-43
OBJECTIVE:
To develop a user-friendly visualization application for the automatic annotation of Human Phenotype Ontology (HPO) terms based on large language models and retrieval-augmented generation (RAG) technology, and to validate its performance in an authoritative case dataset.
METHODS:
By integrating the domestic open-source large language model DeepSeek-V3 with RAG technology, an interactive web application was deployed on the Streamlit cloud platform. Using only the latest official HPO dataset as the data source, the lightweight sentence-embedding model BAAI/bge-small-en-v1.5 was employed to construct a FAISS vector index. During the online phase, a four-step closed-loop process is automatically completed: multilingual translation, phenotype phrase extraction, RAG candidate retrieval, term mapping, and official database validation. 121 English case reports publicly released by BMJ Case Reports and Oxford Medical Case Reports (with a gold-standard HPO set of 1 794 terms) were selected for application validation. Precision, recall, and F1 score were calculated and compared horizontally with traditional dictionary tools, standalone large language models, and the similar application "RAG-HPO". Finally, replace the model with the more advanced ChatGPT-5 and evaluate its performance on the newly extracted dataset.
RESULTS:
An HPO term automatic annotation visualization application named PhenoRAG, based on large language models and RAG technology, was successfully developed. Users can access it directly via a web link. Across the 112 cases, a total of 2 150 HPO terms were generated; 2,064 (96.0%) were fully validated by the official database, with a hallucination rate of 1.3% and an HPO ID-name mismatch rate of 2.7%. After deduplication, 1,906 terms remained for testing. The overall precision was 63.65%, recall was 67.34%, and F1 was 65.44%, significantly outperforming traditional annotation tools (F1: 0.45-0.49, P < 0.001). Although PhenoRAG's F1 was lower than that of RAG-HPO (F1 = 0.78, P < 0.001), which relies on a manually constructed synonym database of 54 000 entries plus the HPO dataset, it requires no additional dictionary maintenance and can be used without any background in computer programming. Moreover, after switching to the GPT-5 model, PhenoRAG exhibited no hallucination rate on the new dataset, and its F1 score significantly increased (P = 0.038).
CONCLUSION
Without constructing a synonym database, the PhenoRAG achieved high-accuracy automatic mapping from clinical text to standard HPO terms. It features a low usage threshold, free access, and a Chinese-language interface, and can directly serve rare disease diagnosis, genetic counseling, and research scenarios in China and worldwide, warranting further clinical promotion and multicenter validation.
Humans
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Phenotype
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Biological Ontologies
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Language
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Software
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Large Language Models
3.Long-term survival outcomes and prognostic factors following radical resection of pancreatic body and tail cancer:a retrospective analysis of 992 patients
Dong XU ; Yang WU ; Kai ZHANG ; Nan LYU ; Qianqian WANG ; Pengfei WU ; Jie YIN ; Baobao CAI ; Guodong SHI ; Jianzhen LIN ; Yazhou WANG ; Lingdi YIN ; Zipeng LU ; Min TU ; Jianmin CHEN ; Feng GUO ; Jishu WEI ; Junli WU ; Wentao GAO ; Cuncai DAI ; Yi MIAO ; Kuirong JIANG
Chinese Journal of Surgery 2026;64(1):46-54
Objective:To investigate the survival outcomes and prognostic factors in patients undergoing radical resection for pancreatic body and tail cancer.Methods:A retrospective case series study was conducted on 992 patients who underwent radical resection for pancreatic body and tail cancer at the Pancreatic Center of the First Affiliated Hospital of Nanjing Medical University from January 2016 to June 2024. In this study, 577 (58.2%) were male and 415 (41.8%) were female,with an age of (65±9) years (range: 26 to 86 years). Follow-up continued until June 2024. Survival rates were estimated using the Kaplan-Meier method,and prognostic factors were identified using univariate and multivariate Cox proportional hazards models.Results:Among 992 patients,open surgery was the predominant approach (89.1%, 884/992), and radical antegrade modular pancreatosplenectomy (RAMPS) was performed in 317 patients (32.0%). Combined organ resection,venous resection,and arterial resection were performed in 23.5%, 9.3%,and 11.2% of patients,respectively. The rates of R0, R1-1 mm, and R1-direct resections were 49.8% (494/992),41.5% (412/992), and 8.7% (86/992),respectively. Stage ⅡB was the most common TNM stage (32.2%,319/992). A total of 801 patients (80.8%) received adjuvant chemotherapy. The median follow-up period was 32.0(8.8) months(range:3.2 to 105.3 months),during which 508 patients (51.2%) died. The overall median survival (OS) was 26.4 months,with 1-,3-, and 5-year survival rates of 79.0%,40.0%, and 29.0%, respectively. In the recent five years (from 2020 to 2024), the median OS improved significantly to 34.1 months compared to 20.0 months from 2016 to 2019 ( P<0.01). Histological subtype analysis showed that the median OS time was 26.7 months for pancreatic ductal adenocarcinoma (PDAC, n=855),58.9 months for invasive intraductal papillary mucinous carcinoma (IPMC, n=32),and 15.7 months for adenosquamous carcinoma of pancreas (ASCP, n=73) ( P=0.001). Among PDAC patients, adjuvant chemotherapy significantly improved survival (29.1 months vs. 14.4 months, P<0.01);in IPMC patients, adjuvant chemotherapy also extended survival (65.7 months vs. 58.9 months, P=0.047). Although ASCP patients receiving chemotherapy had a longer median OS time than those without (18.8 months vs. 8.9 months),the difference was not statistically significant ( P=0.151). Multivariate Cox regression analysis in PDAC patients indicated that adjuvant chemotherapy, R0 resection, T stage,N stage,and tumor differentiation were independent prognostic factors ( P<0.01). The median OS time by TNM stage was:not reached for stage ⅠA, 51.6 months for ⅠB, 25.5 months for ⅡA, 23.7 months for ⅡB, 23.0 months for Ⅲ, and 14.4 months for Ⅳ. The median OS time for R0,R1-1 mm,and R1-direct resections was 34.1,24.7,and 15.7 months,respectively ( P<0.01). Conclusion:Adjuvant chemotherapy,R0 resection,tumor stage,and differentiation are independent prognostic factors for pancreatic body and tail cancer.
4.Disease burden and changing trends of bladder cancer in China and globally in 1992 - 2021
Zhengnan LI ; Zhuang LI ; Yuanyuan LUO ; Bo YU ; Hao SU ; GuangYong CAO ; Kai YIN ; Dongbo YUAN ; Jianguo ZHU
Journal of Public Health and Preventive Medicine 2026;37(3):8-13
Objective To analyze the disease burden and trends of bladder cancer in China and globally from 1992 to 2021. Methods Using the GBD 2021 database, the incidence, prevalence, mortality, and disability-adjusted life years (DALYs) rates of bladder cancer in China and globally from 1992–2021 were analyzed. Average annual percentage change (AAPC) was calculated using Joinpoint regression. Subgroup analyses by sex and age were conducted, and a Bayesian age-period-cohort (BAPC) model was used to predict trends in age-standardized incidence rate (ASIR) and age-standardized mortality rate (ASMR) for the next 15 years. Results In 2021, China reported 106 000 new cases (ASIR: 5.14/100 000), 571 000 prevalent cases (age-standardized prevalence rate, ASPR: 26.61/100 000), 43 000 deaths (ASMR: 2.34/100 000), and a DALY rate of 45.31/100 000. From 1992–2021, China showed upward trends in ASIR and ASPR but declines in ASMR and DALYs, while global ASIR, ASMR, and DALYs decreased overall with slow ASPR growth. The peak cases in China and globally were both concentrated in the 65-79 age group, with a significantly higher burden on males than females. In China, smoking-related ASMR and ASDR exceeded global averages and rose, whereas high glucose-related indexes were lower and declined. Projections for 2021–2036 indicated that the global incidence and mortality rates would be rising, but ASIR/ASPR would be declining, while in China, the incidence rate would continue to rise, and the mortality rate will stabilize, with a significant increase in ASIR and a gradual decrease in ASPR. Conclusion From 1992 to 2021, the incidence of bladder cancer in China has shown a continuous upward trend and is projected to persist in the future, with significant gender and age differences. Particular attention should be given to elderly males aged 85-89. The disease burden of bladder cancer attributable to smoking continues to rise, highlighting the urgent need to strengthen tobacco control policies.
5.Prolonged cerebral oxygenation surveillance with algorithm-based management: a neurocritical care bundle for extremely preterm infants
Kai-Hsiang HSU ; Wei-Hung WU ; Shu-Yu LIN ; Chih-Chen CHANG ; Mei-Yin LAI ; I-Hsyuan WU ; Shih-Ming CHU ; Ming-Chou CHIANG ; Reyin LIEN
Clinical and Experimental Pediatrics 2026;69(4):304-312
Background:
Cerebral hypoxia-ischemia impairs brain development in extremely preterm infants and is associated with poor neurological outcomes. Near-infrared spectroscopy (NIRS) is a noninvasive continuous monitoring method for regional cerebral oxygen saturation (rcSO2).Purpose: This study evaluated the clinical feasibility and neurological impact of a neurocritical care bundle that incorporates prolonged multidisciplinary hemodynamic monitoring and a stepwise management algorithm.
Methods:
Preterm infants with a gestational age (GA) ≤28 weeks or birth weight (BW) ≤1,000 g were prospectively enrolled in a bundle group subjected to NIRS for rcSO2, electrical cardiometry for cardiac output, and daily brain and cardiac echography during the first 72 hours of life. Monitoring was repeated weekly in the first month and then monthly until discharge or the term-equivalent age (TEA) was reached. We implemented a stepwise management algorithm for treating cerebral hypoxia. The primary outcome was a composite of mortality and adverse neurological events (structural abnormalities or electroencephalogram-confirmed seizures) before discharge. The secondary outcomes were the physiological pattern of rcSO2 within the initial 72 hours and up to discharge or TEA.
Results:
Thirty preterm infants (GA, 27.1±2.0 weeks; BW, 830±225 g) were enrolled in the bundle group. The mean time-averaged rcSO2 (66.8%±10.3%) was not associated with GA or BW. However, postnatal age appeared to influence physiological rcSO2 changes, given that rcSO2 values were higher during the initial 72 hours than at subsequent intervals. Seven infants (23.3%) had poor outcomes and significantly lower time-averaged rcSO2 (51.1% [50.0%–65.2%] vs. 71.8% [67.1%–73.1%], P=0.002). Multivariate regression indicated that a lower rcSO2 was an independent risk factor, and a 65% threshold showed an optimal predictive value for poor outcomes.
Conclusion
The neurocritical care bundle helped identify preterm infants at risk of cerebral hypoxia, and lower rcSO2 was an independent risk factor for composite mortality and adverse neurological outcomes.
6.Protective mechanism of Dachengqi decoction on intestinal mucosal barrier:a network pharmacology study focused on autophagy
Xing LU ; Kai ZHANG ; Jing ZHAO ; Shiya ZHANG ; Zhibo LI ; Xinjing GAO ; Lei XU ; Chengfen YIN
Chinese Journal of Integrated Traditional and Western Medicine in Intensive and Critical Care 2025;32(4):454-459
Objective To explore and verify the active components of Dachengqi decoction in regulating autophagy and its mechanism of protecting the intestinal mucosal barrier through network pharmacology and animal experiments.Methods The chemical components and autophagy-related target points of Dachengqi decoction were retrieved from the Traditional Chinese Medicine Systems Pharmacology Database Analysis Platform(TCMSP)and GeneCards databases.The intersection of the drug target points and disease target points was taken and analyzed.The Cytoscape 3.10.2 software's Network Analyzer tool was used to analyze the drug components and target points,and the core target points were screened out to construct a traditional Chinese medicine compound regulatory network.The drug active component target point-disease network model and protein-protein interaction(PPI)network were visualized.Then,30 C57BL/6J mice were randomly divided into the Dachengqi decoction group,the intestinal infection group,and the control group,with 10 mice in each group.The intestinal infection group was given 200 μL/d of Klebsiella pneumoniae strain by gavage for 5 consecutive days,with a colony count of 109 CFU/mL,to create an intestinal infection model.The control group was given 200 μL/d of sterile normal saline by gavage.The Dachengqi decoction group(drug composition:Rhubarb 12 g,Aurantii Fructus 12 g,Magnolia Officinalis 24 g,Mirabilite 9 g,the drugs were dissolved in boiling distilled water to make a 1 kg/L solution)was given by gavage at a dose of 8 g·kg-1·d-1 for 3 consecutive days,and then given Klebsiella pneumoniae by gavage for 5 consecutive days on the 4th day.Detection indicators and methods:after the experiment,the mice were sacrificed and the terminal ileum tissues were collected.The tissues were stained with hematoxylin-eosin(HE),and the pathological changes of the intestinal mucosa were observed under a light microscope;immunofluorescence staining was used to observe the positive expressions of junction proteins ZO-1,Claudin-2,light chain 3-Ⅱ(LC3-Ⅱ),and Beclin-1 and the intestinal mucosal autophagy;the mRNA expression levels of autophagy genes were determined by polymerase chain reaction(PCR).Results The intersection of the obtained drug targets and disease targets yielded 111 potential autophagy-related targets for drug treatment of diseases.Key targets included β2-adrenergic receptor(ADRB2),heme oxygenase-1(HO-1),etc.,and the signaling pathways involved included AMP-activated protein kinase(AMPK)pathway,mammalian target of rapamycin(mTOR)pathway,etc.Animal experiments confirmed that the intestinal mucosal barrier function in the Dachengqi decoction group was better than that in the intestinal infection group,and the positive expression of microtubule-associated protein 1 lingt chain 3-Ⅱ(LC3-Ⅱ)and autophagy gene Beclin1 was significantly higher than that in the intestinal infection group.Transcriptome sequencing results showed that the key genes associated with autophagy and oxidative stress included ADRB2,HO-1,etc.The mRNA expression levels of ADRB2 and HO-1 in the Dachengqi decoction group were significantly higher than those in the intestinal infection group[HO-1 mRNA expression(FPKM):11.20±0.80 vs.6.63±0.53,ADRB2 mRNA expression(FPKM):6.98±0.54 vs.3.98±0.32,both P<0.01],verifying some of the predictions from network pharmacology.Conclusions Dachengqi decoction regulates autophagy through multiple components,multiple targets and multiple pathways,protecting the intestinal mucosal barrier function and reducing the translocation of intestinal microbiota.This lays a certain foundation for further in-depth research on the mechanism of reducing intestinal bacterial translocation by Dachengqi decoction.
7.Impact of hip synovitis on the long-term outcomes of free vascularized fibular grafting for osteonecrosis of femoral head
Daoyu ZHU ; Kai FU ; Haiyan HE ; Qianying CAI ; Hao PENG ; Shengbao CHEN ; Jimin YIN ; Pengbo LUO ; Dongxu JIN ; Changqing ZHANG ; Youshui GAO
Journal of Shanghai Jiaotong University(Medical Science) 2025;45(3):357-364
Objective·To observe the impact of hip synovitis on the long-term outcomes of free vascularized fibular grafting(FVFG)for osteonecrosis of femoral head(ONFH).Methods·Between October 2001 and December 2013,370 patients diagnosed with ONFH(556 hips)underwent FVFG.Preoperative synovitis was assessed using magnetic resonance imaging(MRI)and quantified with the Hip Inflammation MRI Scoring System(HIMRISS).Patients were divided into no synovitis group,moderate synovitis group,and severe synovitis group.Harris hip scores and the incidence of total hip arthroplasty were collected with an average follow-up duration of 90.5 months(range:5-215 months).Hip survival failure(defined as a Harris hip score lower than 80 at the final follow-up or the occurrence of total hip arthroplasty)was calculated.Multivariable Cox regression analysis was adopted to compare the influence of different degrees of synovial inflammation on long-term prognosis.Results·The proportion of hip survival failure was 28.0%in patients without synovitis and 28.5%in those with moderate synovitis,whereas it was significantly higher(60.4%)in patients with severe synovitis.The results of multivariable Cox regression analysis showed that severe synovitis was an independent risk factor for poor prognosis(HR 2.06,95%CI 1.21-3.53)after adjusting for age,gender,education level,marital status,ONFH type,affected side of ONFH,smoking history,baseline Harris hip score and other hip MRI-based covariates(collapse,bone marrow edema,and degeneration).Conclusion·Severe synovitis in patients with ONFH significantly increases the failure rate of hip preservation after FVFG,and the severity of synovitis should be considered in surgical decision-making.
8.Effect of side-to-end anastomosis on postoperative bowel function in rectal cancer surgery: a prospective single-center randomized controlled trial
Chang WANG ; Fan LIU ; Sen HOU ; Zhanlong SHEN ; Mujun YIN ; Xiaodong YANG ; Kewei JIANG ; Qiwei XIE ; Bin LIANG ; Kai SHEN ; Zhidong GAO ; Yingjiang YE
Chinese Journal of Gastrointestinal Surgery 2025;28(6):644-652
Objective:To compare bowel function 12 months after surgery between side-to-end anastomosis (SEA) and end-to-end anastomosis (EEA) groups of patients who had undergone rectal cancer resection.Methods:This single-center, prospective, open-label, phase III randomized controlled trial was approved by the Ethics Committee of Peking University People's Hospital (2018PHB040-01) and registered at ClinicalTrials. org (NCT03669237). Inclusion criteria were as follows: (1) histologically confirmed rectal adenocarcinoma; (2) tumor located 0 to 12 cm from the anal verge; (3) age≥18 years; and (4) planned R0 resection with primary reconstruction. Exclusion criteria included: (1) emergency surgery; (2) cognitive impairment; (3) non-primary anastomosis; (4) history of left-sided colonic or anorectal surgery; and (5) preexisting chronic defecation dysfunction. Eligible rectal cancer patients scheduled for elective sphincter-preserving surgery at Peking University People's Hospital were prospectively enrolled between October 2018 and March 2021 and randomly assigned to either the EEA group or the SEA group via computer-generated numbers prior to entering the operating room. All patients underwent standard radical tumor resection. Bowel function was evaluated by the low anterior resection syndrome (LARS) questionnaire. It consists of five single-choice questions and yields a total score ranging from 0 to 42. Defecation function is categorized into three levels: no LARS (0-20 points), minor LARS (21-29 points), and major LARS (30-42 points). The primary endpoint was the LARS score 12 months after surgery. Secondary endpoints included LARS scores from 1 to 11 months and during long-term follow-up(>12 months). The final follow-up was completed in July 2022. All randomized patients were included in the intention-to-treat set (ITTS). The full analysis set (FAS) was defined as ITTS patients with valid outcome data. All primary statistical analyses were performed in the FAS, and results were further compared in the per-protocol set (PPS) based on the actual treatment received.Results:A total of 323 patients underwent eligibility assessment, of whom 71 did not meet the inclusion criteria and 52 declined to participate. Ultimately, 200 patients were randomized. Median age was 64 years and 85 were women. The SEA and EEA groups comprised 102 and 98 patients, respectively. A total of 181 patients (90.5%) were included in the FAS, and 170 (85.0%) were included in the PPS. Among these, the 12-month LARS score was evaluated in 178 patients (98.3%) in the FAS and in 167 (98.2%) in the PPS. Median LARS score at 1–12 months were significantly lower in the SEA group in both the FAS dataset [12 months:8 (interquartile range [IQR], 0–22) vs. 14 (IQR, 8–29); Z=2.687, P=0.007] and the PPS dataset [12 months: 8 (IQR, 0–22) vs. 14 (IQR, 6–29); Z=2.543, P=0.011]. During long-term follow-up, the median LARS score was also significantly lower in the SEA group in the FAS dataset [2 (IQR, 0–4) vs. 11 (IQR, 2–23); Z=2.968, P=0.003] and the PPS dataset [2 (IQR, 0–14) vs. 11 (2, 27); Z=2.687, P=0.007]. Conclusion:Compared with the EEA group, bowel function was superior in the SEA group 1 year after surgery and during long-term follow-up.
9.Characterization of a Physiological Mock Circulation System Based on Capillary-Bundle Resistance Element
Dengji LIU ; Xinke CHEN ; Lisha HAN ; Zhen CAO ; Qingzhuo CHI ; Kai YIN ; Ying HE
Journal of Medical Biomechanics 2025;40(5):1256-1264
Objective To investigate the feasibility of parallel capillary bundle arrays for physiomimetic impedance modeling and establish a parametric quantification framework,thereby providing a customizable impedance characterization methodology for diverse in-vitro mock circulation researches.Methods Based on the parallel flow resistance and Poiseuille equation,a tube resistance element with multiple parallel-aligned capillary glass tubes was designed and fabricated.The resistance values of the capillary-bundle and a ball valve were measured through constant flow experiments analogous to electrical resistance measurement method.Moreover,a simple lumped-parameter mock circulation loop was constructed and the pressure and flow rate for each node of the loop were measured under different input flow waveforms.An 0D-Windkessel model corresponding to the experiment was developed.The impedance and compliance were adjusted to match the simulated and experimental pressure and flow waveforms.The accuracy of the capillary bundle impedance in pulsatile experiments was verified by using the computational resistance values.Results The constant-flow impedance calibration experiments revealed that the capillary bundle impedance remained unaffected by flow rate variations over a wide flow range.When the capillary bundle impedance was integrated into the pulsatile circulatory system and the same impedance value obtained from the constant-flow calibration was applied in the computational model,the resulting pressure and flow waveforms showed good agreement with those measured in the pulsatile experiments.However,when the ball valves with nominally identical impedance values were inserted in the pulsatile system,the calculated impedance exhibited a two-fold difference,and significant discrepancies were observed between the simulated and experimental terminal flow waveforms.Conclusions The capillary bundle impedance maintains a constant value regardless of flow rate variations.Once the calibrated resistance value is determined through constant flow experiments,it can be directly applied to pulsatile systems.This approach can provide quantitative pulsatile flow conditions for testing various medical devices.
10.A Milestone in Collaboration: The Journal of Chest Surgery Becomes the Joint Official Journal of the Korean Society for Thoracic and Cardiovascular Surgery and the Taiwan Society of Thoracic Surgeons
Mong-Wei LIN ; Yi-Ting YEN ; Shah-Hwa CHOU ; Hsao-Hsun HSU ; Yin-Kai CHAO
Journal of Chest Surgery 2025;58(1):3-4


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