High-performance piezoelectric energy harvesting in amorphous perovskite thin films deposited directly on a plastic substrate.

Most reported thin-film piezoelectric energy harvesters have been based on cantilever-type crystalline ferroelectric oxide thin films deposited on rigid substrates, which utilize vibrational input sources. Herein, we introduce flexible amorphous thin-film energy harvesters based on perovskite CaCu3Ti4O12 (CCTO) thin films on a plastic substrate for highly competitive electromechanical energy harvesting. The room-temperature sputtering of CCTO thin films enable the use of plastic substrates to secure reliable flexibility, which has not been available thus far. Surprisingly, the resultant amorphous nature of the films results in an output voltage and power density of ~38.7 V and ~2.8 × 106 µW cm-3, respectively, which break the previously reported record for typical polycrystalline ferroelectric oxide thin-film cantilevers. The origin of this excellent electromechanical energy conversion is systematically explored as being related to the localized permanent dipoles of TiO6 octahedra and lowered dielectric constant in the amorphous state, depending on the stoichiometry and defect states. This is the leading example of a high-performance flexible piezoelectric energy harvester based on perovskite oxides not requiring a complex process for transferring films onto a plastic substrate.

PIP2 Is An Electrostatic Catalyst for Vesicle Fusion by Lowering the Hydration Energy: Arresting Vesicle Fusion by Masking PIP2.

Lipids are key factors in regulating membrane fusion. Lipids are not only structural components to form membranes but also active catalysts for vesicle fusion and neurotransmitter release, which are driven by soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins. SNARE proteins seem to be partially assembled before fusion, but the mechanisms that arrest vesicle fusion before Ca2+ influx are still not clear. Here, we show that phosphatidylinositol 4,5-bisphosphate (PIP2) electrostatically triggers vesicle fusion as an electrostatic catalyst by lowering the hydration energy and that a myristoylated alanine-rich C-kinase substrate (MARCKS), a PIP2-binding protein, arrests vesicle fusion in a vesicle docking state where the SNARE complex is partially assembled. Vesicle-mimicking liposomes fail to reproduce vesicle fusion arrest by masking PIP2, indicating that native vesicles are essential for the reconstitution of physiological vesicle fusion. PIP2 attracts cations to repel water molecules from membranes, thus lowering the hydration energy barrier.

Predicting peritoneal recurrence after radical gastrectomy for gastric cancer: Validation of a prediction model (PERI-Gastric 1 and PERI-Gastric 2) on a Korean database.

BACKGROUND: Peritoneal recurrence is a significant cause of treatment failure after radical gastrectomy for gastric cancer. The prediction of metachronous peritoneal recurrence would have a significantly impact risk stratification and tailored treatment planning. This study aimed to externally validate the previously established PERI-Gastric 1 and 2 models to assess their generalizability in an independent population. METHODS: Retrospective external validation was conducted on a cohort of 8564 patients who underwent elective gastrectomy for stage Ib-IIIc gastric cancer between 1998 and 2018 at the Yonsei Cancer Center. Discrimination was tested using the area under the receiver operating characteristic curves (AUROC). Accuracy was tested by plotting observations against the predicted risk of peritoneal recurrence and analyzing the resulting calibration plots. Clinical usefulness was tested with a decision curve analysis. RESULTS: In the validation cohort, PERI-Gastric 1 and PERI-Gastric 2 exhibited an AUROC of 0.766 (95 % C.I. 0.752-0.778) and 0.767 (95 % C.I. 0.755-0.780), a calibration-in-the-large of 0.935 and 0.700, a calibration belt with a 95 % C.I. over the bisector in the risk range of 24%-33 % and 35%-47 %. The decision curve analysis revealed a positive net benefit in the risk range of 10%-42 % and 15%-45 %, respectively. CONCLUSIONS: This study presents the external validation of the PERI-Gastric 1 and 2 scores in an Eastern population. The models demonstrated fair discrimination and satisfactory calibration for predicting the risk of peritoneal recurrence after radical gastrectomy, even in Eastern patients. PERI-Gastric 1 and 2 scores could also be applied to predict the risk of metachronous peritoneal recurrence in Eastern populations.

Hypothalamic neuronal activation in non-human primates drives naturalistic goal-directed eating behavior.

Maladaptive feeding behavior is the primary cause of modern obesity. While the causal influence of the lateral hypothalamic area (LHA) on eating behavior has been established in rodents, there is currently no primate-based evidence available on naturalistic eating behaviors. We investigated the role of LHA GABAergic (LHAGABA) neurons in eating using chemogenetics in three macaques. LHAGABA neuron activation significantly increased naturalistic goal-directed behaviors and food motivation, predominantly for palatable food. Positron emission tomography and magnetic resonance spectroscopy validated chemogenetic activation. Resting-state functional magnetic resonance imaging revealed that the functional connectivity (FC) between the LHA and frontal areas was increased, while the FC between the frontal cortices was decreased after LHAGABA neuron activation. Thus, our study elucidates the role of LHAGABA neurons in eating and obesity therapeutics for primates and humans.

Superior lymph node harvest by fluorescent lymphography during minimally invasive gastrectomy for gastric cancer patients with high body mass index.

BACKGROUND: Fluorescent lymphography (FL) using indocyanine green (ICG) allows for the visualization of all draining lymph nodes (LNs), thereby increasing LN retrieval. However, no studies have assessed the efficacy of FL in high body mass index (BMI) gastric cancer patients, even as LN yield decreases with increasing BMI in gastrectomy. This study aimed to investigate the influence of FL on LN retrieval in high BMI gastric cancer patients. METHODS: Gastric cancer patients who underwent laparoscopic or robotic gastrectomies from 2013 to 2021 were included. Patients were classified into two groups, with FL (FL group) or without FL (non-FL group). The effect of FL on LN retrieval was assessed by BMI. Inverse probability of treatment weighting (IPTW) was used to ensure comparability between groups. RESULTS: Retrieved LN number decreased as BMI increased regardless of FL application (P < 0.001). According to the IPTW analysis, the mean retrieved LN number was significantly higher in the FL group (48.4 ± 18.5) than in the non-FL group (39.8 ± 16.3, P < 0.001), irrespective of BMI. The FL group exhibited a significantly higher proportion of patients with 16 or more LNs (99.5%) than the non-FL group (98.1%, P < 0.001). The FL group also had a significantly higher proportion of patients with 30 or more LNs (86.6%) than the non-FL group (72.2%, P < 0.001). In both the normal and high-BMI patients, the FL group had a significantly larger percentage of patients with a higher nodal classification than the non-FL group. CONCLUSION: FL resulted in more LN retrieval, even in high BMI patients. FL ensures accurate staging by maintaining the appropriate retrieved LN number in high BMI gastric cancer patients.

Identifying the best candidates for reduced port gastrectomy.

BACKGROUND: Previous studies have focused on the non-inferiority of RPG compared with conventional port gastrectomy (CPG); however, we assumed that some candidates might derive more significant benefit from RPG over CPG. METHODS: We retrospectively analyzed the clinicopathological and perioperative parameters of 1442 patients with gastric cancer treated by gastrectomy between 2009 and 2022. The C-reactive protein level on postoperative day 3 (CRPD3) was used as a surrogate parameter for surgical trauma. Patients were grouped according to the extent of gastrectomy [subtotal gastrectomy (STG) or total gastrectomy (TG)] and lymph node dissection (D1+ or D2). The degree of surgical trauma, bowel recovery, and hospital stay between RPG and CPG was compared among those patient groups. RESULTS: Of 1442 patients, 889, 354, 129, and 70 were grouped as STGD1+, STGD2, TGD1+, and TGD2, respectively. Compared with CPG, RPG significantly decreased CRPD3 only among patients in the STGD1+ group (CPG: n = 653, 84.49 mg/L, 95% CI 80.53-88.45 vs. RPG: n = 236, 70.01 mg/L, 95% CI 63.92-76.09, P < 0.001). In addition, the RPG method significantly shortens bowel recovery and hospital stay in the STGD1+ (P < 0.001 and P < 0.001), STGD2 (P < 0.001 and P < 0.001), and TGD1+ (P = 0.026 and P = 0.007), respectively. No difference was observed in the TGD2 group (P = 0.313 and P = 0.740). CONCLUSIONS: The best candidates for RPG are patients who undergo STGD1+, followed by STGD2 and TG D1+, considering the reduction in CRPD3, bowel recovery, and hospital stay.

mRNA-HPV vaccine encoding E6 and E7 improves therapeutic potential for HPV-mediated cancers via subcutaneous immunization.

The E6 and E7 proteins of specific subtypes of human papillomavirus (HPV), including HPV 16 and 18, are highly associated with cervical cancer as they modulate cell cycle regulation. The aim of this study was to investigate the potential antitumor effects of a messenger RNA-HPV therapeutic vaccine (mHTV) containing nononcogenic E6 and E7 proteins. To achieve this, C57BL/6j mice were injected with the vaccine via both intramuscular and subcutaneous routes, and the resulting effects were evaluated. mHTV immunization markedly induced robust T cell-mediated immune responses and significantly suppressed tumor growth in both subcutaneous and orthotopic tumor-implanted mouse model, with a significant infiltration of immune cells into tumor tissues. Tumor retransplantation at day 62 postprimary vaccination completely halted progression in all mHTV-treated mice. Furthermore, tumor expansion was significantly reduced upon TC-1 transplantation 160 days after the last immunization. Immunization of rhesus monkeys with mHTV elicited promising immune responses. The immunogenicity of mHTV in nonhuman primates provides strong evidence for clinical application against HPV-related cancers in humans. All data suggest that mHTV can be used as both a therapeutic and prophylactic vaccine.

Robust 2D layered MXene matrix-boron carbide hybrid films for neutron radiation shielding.

Large-scale fabrication of neutron-shielding films with flexible or complex shapes is challenging. Uniform and high boron carbide (B4C) filler loads with sufficient workability are needed to achieve good neutron-absorption capacity. Here, we show that a two-dimensional (2D) Ti3C2Tx MXene hybrid film with homogeneously distributed B4C particles exhibits high mechanical flexibility and anomalous neutron-shielding properties. Layered and solution-processable 2D Ti3C2Tx MXene flakes serve as an ideal robust and flexible matrix for high-content B4C fillers (60 wt.%). In addition, the preparation of a scalable neutron shielding MXene/B4C hybrid paint is demonstrated. This composite can be directly integrated with various large-scale surfaces (e.g., stainless steel, glass, and nylon). Because of their low thickness, simple and scalable preparation method, and an absorption capacity of 39.8% for neutrons emitted from a 241Am-9Be source, the 2D Ti3C2Tx MXene hybrid films are promising candidates for use in wearable and lightweight applications.

Safety and feasibility of reduced-port robotic distal gastrectomy for gastric cancer: a phase I/II clinical trial using the da Vinci Single Port(SP) robotic system.

Minimally invasive surgery reduces surgical trauma and the size and number of incisions. The da Vinci SP robotic surgical system was designed to overcome the technical demands of single-incision laparoscopic surgery. This study aimed to demonstrate the safety and feasibility of single-port (SP) robotic distal gastrectomy (SPRDG) for patients with gastric cancer using the da Vinci SP system (Intuitive Surgical Inc., Sunnyvale, CA, USA). This study was designed as a single-arm prospective phase I/II clinical trial of SPRDG (first posted date: 21/09/2021, NCT05051670; clinicaltrials.gov). SPRDG using the da Vinci SP system was performed on 19 patients with gastric cancer between December 2021 and October 2022. The primary outcome was the safety of SPRDG as measured by major postoperative complications. The secondary outcomes were operation time, bleeding amount, bowel motility recovery, and length of hospital stay. SPRDG was performed in all 19 patients without unexpected events, such as use of additional trocars or conversion to laparoscopic or open surgery. No major complications occurred postoperatively (0/19, 0.0%). The mean operation time was 218 min (range 164-286 min). The mean hospital stay duration was 3.2 days (range 2-4 days). This phase I/II clinical trial, performed by a single expert surgeon, demonstrated the safety and feasibility of SPRDG with the da Vinci SP system in selected patients with gastric cancer. SPRDG could be a reasonable alternative to conventional or reduced-port minimally invasive gastrectomy, as it has cosmetic advantages, early recovery, and safe discharge.

Intracorporeal modified delta-shaped gastroduodenostomy during 2-port distal gastrectomy: technical aspects and short-term outcomes.

Purpose: Surgeons have become increasingly interested in reduced-port gastrectomy to minimize trauma while maintaining oncologic safety. Although gastroduodenostomy has the benefits of better nutritional outcomes and fewer postoperative complications than other types of reconstruction, gastroduodenostomy is not a preferred option for reduced-port distal gastrectomy because of technical difficulties. In this study, we describe our intracorporeal modified delta-shaped gastroduodenostomy technique, which is easily applicable during 2-port distal gastrectomy. Methods: We retrospectively reviewed our database of 30 consecutive patients with gastric cancer who underwent 2-port distal gastrectomy with intracorporeal modified delta-shaped gastroduodenostomy from October 2016 to May 2021. In this reduced-port approach, we used a Tropian Single port (TROPIAN TECH) via a 25-mm transumbilical incision and a 12-mm port at the right flank. All anastomoses were performed using a 60-mm endolinear stapler. We used 3 additional sutures to provide proper traction and support for the anastomosis. Results: Mean ± standard deviation of operation time was 148.9 ± 34.7 minutes; reconstruction time was 13.2 ± 4.6 minutes; estimated blood loss was 29.3 ± 44.4 mL; and length of hospital stay was 4.5 ± 1.2 postoperative days. A total of 11 patients (36.7%) had a Clavien-Dindo grade I or grade II complication, and there were no grade IIIa or higher complications. Conclusion: Intracorporeal modified delta-shaped gastroduodenostomy was safely performed via a 2-port approach, resulting in acceptable surgical outcomes and no major complications.

Fluorescence-guided Two-port Robotic Gastrectomy Versus Conventional Laparoscopic Gastrectomy: A Nonrandomized Controlled Trial.

Objective: To compare the number of retrieved lymph nodes between conventional laparoscopic gastrectomy (CLG) and robotic gastrectomy integrated with fluorescence guidance and a two-port system (integrated robotic gastrectomy, IRG). Background: The benefits of robotic surgery over laparoscopic surgery for gastric cancer have not yet been established. Using built-in features of robotic system, further benefit can be provided to the patients with effective lymphadenectomy and enhanced recovery. Methods: A nonrandomized controlled trial was performed by a single surgeon at single-center, tertiary referral hospital between January 2018 and October 2021. Overall, 140 patients scheduled to undergo minimally invasive subtotal gastrectomy for early gastric cancer were enrolled. The primary endpoint was the number of retrieved lymph nodes. Secondary endpoints were complications, hospital stay, pain score, body image, and operative cost. Results: This study analyzed 124 patients in the per-protocol group (IRG, 64; CLG, 60). The number of retrieved lymph nodes was higher in the IRG group than those in the CLG group (IRG vs CLG; 42.1 ± 17.9 vs 35.1 ± 14.6, P = 0.019). Moreover, other surgical parameters, such as hospital stay (4.1 ± 1.0 vs 5.2 ± 1.8, P < 0.001) and body image scale (better in 4 of the 10 questions), were significantly better in the IRG than in the CLG. Conclusions: Robotic surgical procedures integrated with fluorescence guidance and a reduced-port system yielded more retrieved lymph nodes. In addition, the IRG group showed better perioperative surgical outcomes, particularly regarding the length of hospital stay and postoperative body image. Trial registration: NCT03396354.

Photosensitizing deep-seated cancer cells with photoprotein-conjugated upconversion nanoparticles.

To resolve the problem of target specificity and light transmission to deep-seated tissues in photodynamic therapy (PDT), we report a cancer cell-targeted photosensitizer using photoprotein-conjugated upconversion nanoparticles (UCNPs) with high target specificity and efficient light transmission to deep tissues. Core-shell UCNPs with low internal energy back transfer were conjugated with recombinant proteins that consists of a photosensitizer (KillerRed; KR) and a cancer cell-targeted lead peptide (LP). Under near infrared (NIR)-irradiating condition, the UCNP-KR-LP generated superoxide anion radicals as reactive oxygen species via NIR-to-green light conversion and exhibited excellent specificity to target cancer cells through receptor-mediated cell adhesion. Consequently, this photosensitizing process facilitated rapid cell death in cancer cell lines (MCF-7, MDA-MB-231, and U-87MG) overexpressing integrin beta 1 (ITGB1) receptors but not in a cell line (SK-BR-3) with reduced ITGB1 expression and a non-invasive normal breast cell line (MCF-10A). In contrast to green light irradiation, NIR light irradiation exhibited significant PDT efficacy in cancer cells located beneath porcine skin tissues up to a depth of 10 mm, as well as in vivo tumor xenograft mouse models. This finding suggests that the designed nanocomposite is useful for sensing and targeting various deep-seated tumors.

Resistin-like Molecule α and Pulmonary Vascular Remodeling: A Multi-Strain Murine Model of Antigen and Urban Ambient Particulate Matter Co-Exposure.

Pulmonary hypertension (PH) has a high mortality and few treatment options. Adaptive immune mediators of PH in mice challenged with antigen/particulate matter (antigen/PM) has been the focus of our prior work. We identified key roles of type-2- and type-17 responses in C57BL/6 mice. Here, we focused on type-2-response-related cytokines, specifically resistin-like molecule (RELM)α, a critical mediator of hypoxia-induced PH. Because of strain differences in the immune responses to type 2 stimuli, we compared C57BL/6J and BALB/c mice. A model of intraperitoneal antigen sensitization with subsequent, intranasal challenges with antigen/PM (ovalbumin and urban ambient PM2.5) or saline was used in C57BL/6 and BALB/c wild-type or RELMα-/- mice. Vascular remodeling was assessed with histology; right ventricular (RV) pressure, RV weights and cytokines were quantified. Upon challenge with antigen/PM, both C57BL/6 and BALB/c mice developed pulmonary vascular remodeling; these changes were much more prominent in the C57BL/6 strain. Compared to wild-type mice, RELMα-/- had significantly reduced pulmonary vascular remodeling in BALB/c, but not in C57BL/6 mice. RV weights, RV IL-33 and RV IL-33-receptor were significantly increased in BALB/c wild-type mice, but not in BALB/c-RELMα-/- or in C57BL/6-wild-type or C57BL/6-RELMα-/- mice in response to antigen/PM2.5. RV systolic pressures (RVSP) were higher in BALB/c compared to C57BL/6J mice, and RELMα-/- mice were not different from their respective wild-type controls. The RELMα-/- animals demonstrated significantly decreased expression of RELMß and RELMγ, which makes these mice comparable to a situation where human RELMß levels would be significantly modified, as only humans have this single RELM molecule. In BALB/c mice, RELMα was a key contributor to pulmonary vascular remodeling, increase in RV weight and RV cytokine responses induced by exposure to antigen/PM2.5, highlighting the significance of the genetic background for the biological role of RELMα.

3D-Printed Artificial Cilia Arrays: A Versatile Tool for Customizable Mechanosensing.

Bio-inspired cilium-based mechanosensors offer a high level of responsiveness, making them suitable for a wide range of industrial, environmental, and biomedical applications. Despite great promise, the development of sensors with multifunctionality, scalability, customizability, and sensing linearity presents challenges due to the complex sensing mechanisms and fabrication methods involved. To this end, high-aspect-ratio polycaprolactone/graphene cilia structures with high conductivity, and facile fabrication are employed to address these challenges. For these 3D-printed structures, an "inter-cilium contact" sensing mechanism that enables the sensor to function akin to an on-off switch, significantly enhancing sensitivity and reducing ambiguity in detection, is proposed. The cilia structures exhibit high levels of customizability, including thickness, height, spacing, and arrangement, while maintaining mechanical robustness. The simplicity of the sensor design enables highly sensitive detection in diverse applications, encompassing airflow and water flow monitoring, braille detection, and debris recognition. Overall, the unique conductive cilia-based sensing mechanism that is proposed brings several advantages, advancing the development of multi-sensing capabilities and flexible electronic skin applications in smart robotics and human prosthetics.

Comparative analysis of shipboard three-component magnetometer (STCM) and proton precession magnetometer (PPM) datasets in the Australian-Antarctic Ridge.

Two different types of magnetometer, the Proton Precession Magnetometer (PPM) and the Shipboard Three-Component Magnetometer (STCM), each possess its own strengths and weaknesses in their operation. The PPM can measure the total intensity of the Earth's geomagnetic field without requiring complicated post-processing and correction. However, its operation is often limited by the condition of the sea surface. In contrast, the STCM can measure three components of the Earth's field -X, Y and Z - and is not restricted by the sea condition. However, the STCM is highly sensitive to ship's viscous magnetization, which introduces significant noise into the data quality and can lead to a loss in measured geomagnetic field. The simultaneous measurements were carried out using both types of magnetometers along the same section within the Australian-Antarctic Ridge. This region experiences strong measurements of the geomagnetic field due to its proximity to the geomagnetic South Pole. We then compared the differences between the two datasets. For each dataset, we calculated a unique linear trend and subsequently removed the discrepancy between the trends. The corrected STCM data exhibited excellent agreement with the PPM data, suggesting the potential for complementary utilization of the STCM along the PPM.

Prognostic impact of fluorescent lymphography on gastric cancer.

BACKGROUND: Fluorescent lymphography-guided lymphadenectomy (FL) for gastric cancer is gaining popularity. However, its impact on prognosis is not known. This study aimed to assess the prognostic impact of FL in gastric cancer patients. MATERIALS AND METHODS: This study retrospectively analyzed 5678 gastric cancer patients who underwent gastrectomy from 2013 to 2017. The survival was compared between the FLFL group and the conventional lymphadenectomy (non-FL group) using 1:1 propensity score matching after exclusion. Patients in the FL group underwent gastrectomy with systematic lymphadenectomy after endoscopic peritumoral injection of indocyanine green the day before surgery. RESULTS: After propensity score matching, the FL and non-FL groups each had 1064 patients with similar demographic and clinicopathological characteristics. All matched variables had a standardized mean difference under 0.1. The FL group showed a significantly higher number of retrieved lymph nodes (56.2±20.1) than the non-FL group (46.2±18.2, P <0.001). The FL group also had more stage III patients ( P= 0.044) than the non-FL group. The FL group demonstrated higher overall survival ( P= 0.038) and relapse-free survival ( P= 0.036) in stage III compared with the non-FL group. However, no significant differences in overall and relapse-free survival were observed between the two groups for stages I ( P= 0.420 and P= 0.120, respectively) and II ( P= 0.200 and P= 0.280, respectively). CONCLUSION: FL demonstrated a higher survival in stage III gastric cancer patients by the more accurate staging resulting from larger lymph node retrieval. Thus, given its potential to improve prognostication by enhancing staging accuracy, it is recommended as an option to consider the use of FL in clinical practice.

Short-term outcomes and cost-effectiveness of laparoscopic gastrectomy with articulating instruments for gastric cancer compared with the robotic approach.

To overcome the limitations of laparoscopic surgery, robotic systems have been commonly used in the era of minimally invasive surgery despite their high cost. However, the articulation of instruments can be achieved without a robotic system at lower cost using articulating laparoscopic instruments (ALIs). Between May 2021 and May 2022, perioperative outcomes following laparoscopic gastrectomy using ALIs versus robotic gastrectomy were compared. A total of 88 patients underwent laparoscopic gastrectomy using ALIs, while 96 underwent robotic gastrectomy. Baseline characteristics were similar between the groups except for a higher proportion of patients with a medical history in the ALI group (p = 0.013). Clinicopathologic and perioperative outcomes were not significantly different between the groups. However, the operation time was significantly shorter in the ALI group (p = 0.026). No deaths occurred in either group. In conclusion, laparoscopic gastrectomy using ALIs was associated with comparable perioperative surgical outcomes and a shorter operation time compared to robotic gastrectomy in this prospective cohort study.

Chylous Ascites After Gastric Cancer Surgery: Risk Factors and Treatment Results.

PURPOSE: Although chylous ascites is a frequent complication of radical gastrectomy for gastric cancer, proper diagnostic criteria and optimal treatment strategies have not been established. This study aimed to identify the clinical features of chylous ascites and evaluate the treatment outcomes. MATERIALS AND METHODS: We retrospectively analyzed the data of patients who underwent radical gastrectomy between 2013 and 2019. Diagnosis was made when milky fluid or elevated triglyceride levels (≥100 mg/dL) appeared in the drains without a preceding infection. The clinical features, risk factors, and treatment outcomes were assessed according to the initial treatment modalities for fasting and non-fasting groups. RESULTS: Among the 7,388 patients who underwent radical gastrectomy for gastric cancer, 156 (2.1%) experienced chylous ascites. The median length of hospital stay was longer in patients with chylous ascites than in those without (median [interquartile range]: 8.0 [6.0-12.0] vs. 6.0 [5.0-8.0], P<0.001). Low body mass index (adjusted odds ratio [aOR]=0.9; P<0.001), advanced gastric cancer (aOR=1.51, P=0.024), open surgery (reference: laparoscopic surgery; aOR=1.87, P=0.003), and extent of surgical resection (reference: subtotal gastrectomy, total gastrectomy, aOR=1.5, P=0.029; proximal gastrectomy, aOR=2.93, P=0.002) were associated with the occurrence of chylous ascites. The fasting group (n=12) was hospitalized for a longer period than the non-fasting group (n=144) (15.0 [12.5-19.5] vs. 8.0 [6.0-10.0], P<0.001). There was no difference in grade III complication rate (16.7% vs. 4.2%, P=0.117) or readmission rate (16.7% vs. 11.1%, P=0.632) between the groups. CONCLUSIONS: A fat-controlled diet and medication without fasting provided adequate initial treatment for chylous ascites after radical gastrectomy for gastric cancer.

Changes in failure to rescue after gastrectomy at a large-volume center with a 16-year experience in Korea.

Failure to rescue (FTR), the mortality rate among patients with complications, is gaining attention as a hospital quality indicator. However, comprehensive investigation into FTR has rarely been conducted after radical gastrectomy for gastric cancer patients. This study aimed to assess FTR after radical gastrectomy and investigate the associations between FTR and clinicopathologic factors, operative features, and complication types. From 2006 to 2021, 16,851 gastric cancer patients who underwent gastrectomy were retrospectively analyzed. The incidence and risk factors were analyzed for complications, mortality, and FTR. Seventy-six patients had postoperative mortality among 15,984 patients after exclusion. The overall morbidity rate was 10.49% (1676/15,984 = 10.49%), and the FTR rate was 4.53% (76/1676). Risk factor analysis revealed that older age (reference: < 60; vs. 60-79, adjusted odds ratio [OR] 2.07, 95% confidence interval [CI] 1.13-3.79, P = 0.019; vs. ≥ 80, OR 3.74, 95% CI 1.57-8.91, P = 0.003), high ASA score (vs. 1 or 2, OR 2.79, 95% CI 1.59-4.91, P < 0.001), and serosa exposure in pathologic T stage (vs. T1, OR 2.74, 95% CI 1.51-4.97, P < 0.001) were associated with FTR. Moreover, patients who underwent gastrectomy during 2016-2021 were less likely to die when complications occurred than patients who received the surgery in 2006-2010 (OR 0.35, 95% CI 0.18-0.68, P = 0.002). This investigation of FTR after gastrectomy demonstrated that the risk factors for FTR were old age, high ASA score, serosa exposure, and operation period. FTR varied according to the complication types and the period, even in the same institution.

Patient-specific virtual three-dimensional surgical navigation for gastric cancer surgery: A prospective study for preoperative planning and intraoperative guidance.

Introduction: Abdominal computed tomography (CT) can accurately demonstrate organs and vascular structures around the stomach, and its potential role for image guidance is becoming increasingly established. However, solely using two-dimensional CT images to identify critical anatomical structures is undeniably challenging and not surgeon-friendly. To validate the feasibility of a patient-specific 3-D surgical navigation system for preoperative planning and intraoperative guidance during robotic gastric cancer surgery. Materials and methods: A prospective single-arm open-label observational study was conducted. Thirty participants underwent robotic distal gastrectomy for gastric cancer using a virtual surgical navigation system that provides patient-specific 3-D anatomical information with a pneumoperitoneum model using preoperative CT-angiography. Turnaround time and the accuracy of detecting vascular anatomy with its variations were measured, and perioperative outcomes were compared with a control group after propensity-score matching during the same study period. Results: Among 36 registered patients, 6 were excluded from the study. Patient-specific 3-D anatomy reconstruction was successfully implemented without any problems in all 30 patients using preoperative CT. All vessels encountered during gastric cancer surgery were successfully reconstructed, and all vascular origins and variations were identical to operative findings. The operative data and short-term outcomes between the experimental and control group were comparable. The experimental group showed shorter anesthesia time (218.6 min vs. 230.3 min; P=0.299), operative time (177.1 min vs. 193.9 min; P=0.137), and console time (129.3 min vs. 147.4 min; P=0.101) than the control group, although the differences were not statistically significant. Conclusions: Patient-specific 3-D surgical navigation system for robotic gastrectomy for gastric cancer is clinically feasible and applicable with an acceptable turnaround time. This system enables patient-specific preoperative planning and intraoperative navigation by visualizing all the anatomy required for gastrectomy in 3-D models without any error. Clinical trial registration: Clinicaltrials.gov, identifier NCT05039333.