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Two-stage gas-gun ballistic experiments are performed to investigate the feasibility of stratified mixtures with variable global equivalence ratios Φ global for the formation of sphere-induced oblique detonation wave (ODW) and quantify their critical behaviors, which include local quenching and transitional structure to ODW, by testing conventional detonation criteria for uniform mixtures. 2 Φ global H2 + O2 + 3Ar mixtures are tested with different concentration gradients for each fuel-lean/fuel-rich global composition. Opposite responses are observed depending on the global equivalence ratio: the lean mixture of Φ global = 0.7, which forms ODW in the uniform mixture, fails partly in the strongest stratification, whereas the richest mixture of Φ global = 2.0 turns to ODW in the strongly stratified conditions. As elucidated in the authors' previous work, Chapman–Jouguet (C–J) theory, including the curvature effects, reproduces the wave angles of the stable ODWs, as well as provides a good prediction on the local quenching of ODW occurring in the area with less reactive composition. Comparison of different wave regimes observed in the explored conditions reveals that wave curvature governs the critical behaviors of ODW far away from the projectile, whereas the initiation structure around the projectile is also influenced by the non-dimensional diameter. Surface energy theory is proven to quantify well the initiation structure on the projectile using a local equivalence ratio. These results indicate a new possibility of controlling the methodology of ignition and stabilization of detonation in aerospace engines, in which perfect mixing is difficult and non-stoichiometric and non-uniform mixtures are expected. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to investigate the prognostic value of systematic inflammatory response in patients with lymph node-negative colorectal cancer., Methods: We retrospectively investigated 245 patients with lymph node-negative colorectal cancer who underwent curative resection and evaluated the prognostic impact of systematic inflammatory response, which was represented by neutrophil-to-lymphocyte ratio (NLR), prognostic nutritional index (PNI), and C-reactive protein-to-albumin ratio (CAR). Then, the prognostic significance of the systematic inflammatory response on survival was analyzed using the Kaplan-Meier method in patients selected by propensity score matching (PSM) analysis., Results: In the multivariate analysis, CAR ≥ .081 ( P = .004) was independent predictors of disease-free survival, while American Society of Anesthesiologists physical status ≥3 ( P = .049) and CAR ≥ .081 ( P < .001) were independent predictors of overall survival. By PSM analysis, PSM-high-CAR was significantly associated with worse disease-free survival ( P = .043) and overall survival ( P = .041) in patients with lymph node-negative colorectal cancer., Conclusions: C-reactive protein-to-albumin ratio may be a significant indicator of poor long-term outcomes in patients with lymph node-negative colorectal cancer., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: Cholinesterase is a classical nutritional and inflammatory marker. The aim of the present study was to evaluate the value of cholinesterase as a predictive marker for postoperative skeletal muscle loss after gastrectomy for gastric cancer., Methods: The study comprised 68 patients who had undergone gastrectomy for gastric cancer. Skeletal muscle mass was evaluated using skeletal mass index, and major skeletal muscle loss was defined as less than or equal to the median change rate (1-year postoperative/preoperative) of skeletal mass index in all patients. We explored the relationship between postoperative major skeletal muscle loss and disease-free survival and overall survival. Then we investigated the relationship between change rate of skeletal muscle index and serum cholinesterase levels after gastrectomy., Results: The median value of change rate of skeletal mass index was 0.93. Postoperative major skeletal muscle loss was significantly associated with disease-free survival after gastrectomy (P = 0.003). Although major skeletal muscle loss had worse overall survival, it was not significant (P = 0.058). The change rate of skeletal mass index and cholinesterase had a stronger positive correlation compared with other nutritional indices according to Spearman's rank correlation coefficient (r = 0.438, P ≤ 0.001)., Conclusion: Evaluation of serum cholinesterase levels may be valuable for predicting postoperative skeletal muscle loss after gastrectomy, suggesting the importance of cholinesterase in postoperative nutritional management of patients with gastric cancer., (© The Author(s) 2024. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Purpose: The cachexia index is a novel biomarker of cancer cachexia. This systematic review and meta-analysis aimed to evaluate the prognostic impact of cachexia index on prognosis after surgery for gastrointestinal cancer., Methods: In August 2023, we systematically searched PubMed, the Cochrane Library, and Ovid for relevant studies on the oncological outcome after gastrointestinal cancer surgery and analyzed the findings from these studies for meta-analysis., Results: Our systematic and meta-analysis review identified eight studies involving 1876 patients. The number of patients with low cachexia index accounted for 813 patients (43.3%). We found that low cachexia index was associated with worse overall survival (pooled HR, 2.30; 95% CI, 1.85-2.87; z = 7.49; P < 0.001) and disease/relapse/progression-free survival (pooled HR, 1.77; 95% CI, 1.45-2.18; z = 5.50; P < 0.001)., Conclusion: Our meta-analysis showed that cachexia index was associated with oncological outcome after gastrointestinal cancer surgery. However, the limitations of this meta-analysis should be taken into consideration when interpreting the results., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Introduction: Cholinesterase is a classical marker that reflects nutritional and inflammatory status. The aim of the present study was to evaluate the association between serum cholinesterase levels and postoperative infectious complications in patients undergoing gastrectomy for gastric cancer., Materials and Methods: This retrospective study comprised 108 patients who underwent gastrectomy for gastric cancer. We comprehensively investigated the association between clinicopathological variables and postoperative infectious complications after gastrectomy. Then patients were divided into the cholinesterase-high and -low groups to analyze their clinicopathological variables. Finally, we analyzed the types of infectious complications that were most associated with preoperative serum cholinesterase levels., Results: Twenty-six patients (24%) developed postoperative infectious complications. Multivariate analysis revealed that serum cholinesterase levels (P = 0.026) and N stage (P = 0.009) were independent risk factors for postoperative infectious complications. In particular, the incidence of pneumonia (P = 0.001) was significantly higher in the cholinesterase-low group. Age (P = 0.023), cerebrovascular comorbidities (P = 0.006), serum cholinesterase levels (P = 0.013), and total gastrectomy (P = 0.017) were identified as independent risk factors for postoperative pneumonia., Conclusions: Preoperative serum cholinesterase levels were associated with postoperative pneumonia after gastrectomy for gastric cancer, suggesting the importance of preoperative nutritional assessment in gastric cancer surgery., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: The geriatric nutritional risk index (GNRI) is a simple nutritional and inflammatory marker for older adults. The aim of the present study was to investigate the usefulness of the GNRI in older adults who underwent emergency gastrointestinal surgery., Methods: This study included 206 older adults who had undergone emergency gastrointestinal surgery. We retrospectively investigated the relationship between the GNRI and postoperative complications. Univariate and multivariate analyses were performed to evaluate risk factors for postoperative complications. We then evaluated the association between GNRI and clinical variables among older adults undergoing emergency gastrointestinal surgery., Results: Postoperatively, all complications occurred in 89 (43%) older adults, infectious in 53 (26%), and non-infectious in 36 (17%). In the multivariate analysis, age (p = 0.016), GNRI (p = 0.012), operative severity (p = 0.003), and operation time (p = 0.003) were independent risk factors for all postoperative complications. While the GNRI (p = 0.049) was an independent risk factor for infectious complications, age (p = 0.035) and bleeding volume (p = 0.035) were independent risk factors for postoperative non-infectious complications. In the low GNRI group, age (p = 0.029), serum C-reactive protein levels (p < 0.001), and proportion of sarcopenia (p < 0.001) were significantly higher, and the length of hospital stay (p < 0.001) was significantly longer than that in the high GNRI group. In Spearman's rank correlation coefficient, the skeletal mass index and the GNRI had a positive correlation (r = 0.415 and p < 0.001)., Conclusion: The GNRI may be a predictor of postoperative infectious complications in older adults after emergency gastrointestinal surgery, suggesting the usefulness of the GNRI as a nutritional marker and sarcopenia-related parameter., Trial Registration Number: No. 22-16., (© 2023 International Society of Surgery/Société Internationale de Chirurgie (ISS/SIC).)

Purpose: This systematic review and meta-analysis aimed to evaluate the effect of dialysis-dependent chronic kidney disease (CKD) on postoperative complications in colorectal cancer surgery., Methods: In April 2023, we systematically searched PubMed, the Cochrane library, and Ovid for relevant studies on short-term outcomes of colorectal cancer surgery in patients with dialysis and analyzed the findings from these studies for meta-analysis., Results: Our systematic and meta-analysis review identified seven studies involving 50713 patients. We showed that the dialysis group had higher rates of mortality (OR = 4.12, 95%CI: 2.75-6.20, P < 0.001), cardiac complications (OR = 2.45, 95%CI: 1.88-3.21, P < 0.001), and pneumonia (OR = 2.68, 95%CI: 1.83-3.93, P < 0.001). On the other hand, there were no differences in superficial/deep surgical site infection (SSI) (odds ratio [OR] = 1.17, 95%CI: 0.90-1.53, P = 0.230) and organ/space SSI (OR = 1.35, 95%CI: 1.00-1.82, P = 0.053) between the dialysis group and non-dialysis group., Conclusion: Our meta-analysis showed that dialysis-dependent CKD was associated with higher rates of mortality, cardiac complications, and pneumonia after colorectal cancer surgery. However, the limitations of this meta-analysis should be taken into consideration when interpreting the results., (© 2023. Crown.)

Purpose: Cholinesterase is a nutritional marker associated with sarcopenia. The present study evaluated the relationship between cholinesterase and postoperative infectious complications in patients undergoing colorectal resection for colorectal cancer., Methods: The study involved 231 patients who had undergone colorectal resection for colorectal cancer. We retrospectively investigated the relationship between preoperative serum cholinesterase levels and postoperative infectious complications. Univariate and multivariate analyses were performed to identify independent risk factors for postoperative infectious complications. We then performed stratified analyses to assess the interaction between cholinesterase and clinical variables to predict postoperative infectious complications., Results: In the multivariate analysis, the body mass index (P = 0.010), serum cholinesterase levels (P = 0.005), sarcopenia (P = 0.003) and blood loss (P < 0.001) were independent risk factors for postoperative infectious complications. In stratified analyses, the association between serum cholinesterase levels and postoperative infectious complications differed by the sarcopenia status (P interaction  = 0.006)., Conclusion: Preoperative serum cholinesterase levels may be useful for predicting postoperative infectious complications in colorectal cancer surgery. The association differs by the sarcopenia status, suggesting a potential interaction between nutritional markers and sarcopenia., (© 2022. The Author(s) under exclusive licence to Springer Nature Singapore Pte Ltd.)

Purpose: Incisional hernia is a common complication after abdominal surgery, especially in obese patients. The aim of the present study was to evaluate the relationship between sarcobesity and incisional hernia development after laparoscopic colorectal cancer surgery., Methods: In total, 262 patients who underwent laparoscopic colorectal cancer surgery were included in the present study. Univariate and multivariate analyses were performed to evaluate the independent risk factors for the development of incisional hernia. We then performed subgroup analyses to assess the impact of visceral obesity according to clinical variables on the development of incisional hernia in laparoscopic surgery for colorectal cancer surgery., Results: Forty-four patients (16.8%) developed incisional hernias after laparoscopic colorectal cancer surgery. In the univariate analysis, the development of incisional hernia was significantly associated with female sex (P = 0.046), subcutaneous obesity (P = 0.002), visceral obesity (P = 0.002), sarcobesity (P < 0.001), and wound infection (P < 0.001). In the multivariate analysis, sarcobesity (P < 0.001) and wound infection (P < 0.001) were independent predictors of incisional hernia. In subgroup analysis, the odds ratio of visceral obesity was the highest (13.1; 95% confidence interval [CI], 4.51-37.8, P < 0.001) in the subgroup of sarcopenia., Conclusion: Sarcobesity may be a strong predictor of the development of incisional hernia after laparoscopic surgery for colorectal cancer, suggesting the importance of body composition in the development of incisional hernia., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

It is generally believed that time flows in one direction and that a reversal of time's arrow would render the external world non-sensical. We evaluated our ability to tell the direction of time's arrow in a wide range of dynamic scenes in our daily life by presenting 360 video clips in the correct or incorrect direction. Participants, who judged the direction in a speeded manner, erred in 39% of trials when a video was played in reverse, but in only 9% when it was played normally. Due to the bias favouring the 'forward' judgement, the reaction was generally faster for the forward response. However, the reaction became paradoxically faster and more synchronous for the detection of reversal in some critical occasions such as forward motion, free fall, diffusion, division and addition of materials by hand. Another experiment with a fraction of the video clips revealed that reversal replay of these videos provided instantaneous evidence strong enough to overtake the forward judgement bias. We suggest that our brain is equipped with a system that predicts how the external organisms behave or move in these critical occasions and that the prediction error of the system contributes to the fast 'reversal' detection., Competing Interests: We declare we have no competing interests., (© 2023 The Authors.)

Purpose: Cancer cachexia, a complex multifactorial syndrome associated with sarcopenia, negatively affects the quality of life and survival in patients with several cancers. We aimed to develop a new score for cachexia assessment and evaluate its effectiveness in the classification of patients undergoing radical resection for colorectal cancer., Methods: This study included 396 patients who underwent radical resection for Stage I-III colorectal cancer. To develop the Cancer Cachexia Score (CCS), we analyzed predictive factors of cachexia status related to the development of sarcopenia and incorporated significant factors into the score. We then evaluated the relationship between CCS and survival after radical resection for colorectal cancer., Results: As body mass index (P < 0.001), prognostic nutritional index (P = 0.005), and tumor volume (P < 0.001) were significantly associated with the development of sarcopenia, these factors were included in CCS. Using CCS, 221 (56%), 98 (25%), and 77 (19%) patients were diagnosed with mild, moderate, and severe cancer cachexia, respectively. In multivariate analysis, severe CCS (P < 0.001), N stage 1-2 (P < 0.001), and occurrence of postoperative complications (P = 0.007) were independent predictors of disease-free survival. Age ≥ 65 years (P = 0.009), severe CCS (P < 0.001), and N stage 1-2 (P < 0.001) were independent predictors of overall survival., Conclusions: CCS may be a useful prognostic factor for predicting poor survival after radical resection in patients with Stage I-III colorectal cancer., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Aim: Osteopenia and sarcopenia, features of the aging process, are recognized as major health problems in an aging society. This study investigated the prognostic impact of osteosarcopenia, the coexistence of osteopenia and sarcopenia, in older adults undergoing curative resection for colorectal cancer., Methods: We retrospectively reviewed data of older adults aged 65-98 y who had undergone curative resection for colorectal cancer. Osteopenia was evaluated by bone mineral density measurement in the midvertebral core of the 11th thoracic vertebra on preoperative computed tomography images. Sarcopenia was evaluated by measuring the skeletal muscle cross-sectional area at the third lumbar vertebra level. Osteosarcopenia was defined as the coexistence of osteopenia and sarcopenia. We explored the relationship of preoperative osteosarcopenia with the disease-free and overall survival after curative resection., Results: Among the 325 patients included, those with osteosarcopenia had significantly lower overall survival rates than those with osteopenia or sarcopenia alone ( P <  0.01). In the multivariate analysis, male sex ( P =  0.045), C-reactive protein-to-albumin ratio ( P <  0.01), osteosarcopenia ( P <  0.01), pathological T4 stage ( P =  0.023), and pathological N1/N2 stage ( P <  0.01) were independent predictors of disease-free survival, while age ( P <  0.01), male sex ( P =  0.049), C-reactive protein-to-albumin ratio ( P <  0.01), osteosarcopenia ( P <  0.01), pathological T4 stage ( P =  0.036), pathological N1/N2 stage ( P <  0.01), and carbohydrate antigen 19-9 ( P =  0.041) were independent predictors of overall survival., Conclusion: Osteosarcopenia was a strong predictor of poor outcomes in older adults undergoing curative resection for colorectal cancer, suggesting an important role of osteosarcopenia in an aging society., Competing Interests: The authors have no conflicts of interest., (© 2023 The Authors. Annals of Gastroenterological Surgery published by John Wiley & Sons Australia, Ltd on behalf of The Japanese Society of Gastroenterological Surgery.)

Background: Heterotopic pancreas (HP) refers to the presence of abnormally located pancreatic tissue without any anatomic or vascular continuity with the main body of the pancreas. HP can occur in the gastrointestinal tract and be complicated by gastrointestinal bleeding, pancreatitis, obstruction, or malignant generation. Specifically, perforation of the gastrointestinal tract because of HP is extremely rare., Case Presentation: A 91-year-old woman was diagnosed with duodenal perforation, and an emergency laparoscopic operation was performed. The operative findings indicated a tumor and duodenal wall perforation. The tumor and the perforated site were resected with a linear stapler. Histopathological examination revealed the presence of HP tissue in the submucosal layer around the diverticulum without any signs of inflammation. The perforated site was not covered by HP tissues, and the duodenal wall might have been weaker than the other areas, which could have caused the internal pressure to increase and led to the perforation., Conclusions: Preoperative HP diagnosis is difficult, and it is crucial to consider HP as the differential diagnosis in gastrointestinal perforations. The duodenal diverticula can be perforated due to increased internal pressure of the duodenum caused by the imbalanced localization of HP., (© 2022. The Author(s).)

Purpose: Nutritional and inflammatory status have been associated with postoperative recurrence and poor survival in patients with colorectal cancer. The aim of the present study is to investigate the relationship between serum cholinesterase levels and postoperative outcomes among patients who underwent curative resection for colorectal cancer., Methods: The study comprised 174 patients who had undergone curative resection for colorectal cancer. We explored the relationship between preoperative serum cholinesterase levels and disease-free survival and overall survival after curative resection. Then patients were divided into the high-cholinesterase group (n = 102) and the low-cholinesterase group (n = 72) to analyze their clinicopathological variables including other nutritional markers and systemic inflammatory responses., Results: In multivariate analysis, lymph node metastasis (P = 0.011) and serum cholinesterase levels (P < 0.01) were independent predictors of disease-free survival, while lymph node metastasis (P = 0.013), serum cholinesterase levels (P < 0.01), and carbohydrate antigen19-9 (P = 0.022) were independent predictors of overall survival. In the low-cholinesterase group, neutrophil to lymphocyte ratio, (P = 0.021), C-reactive protein to albumin ratio (P < 0.01), and distant metastasis (P < 0.01) were higher, and prognostic nutritional index (P < 0.01) was lower compared with the high-cholinesterase group., Conclusion: Preoperative low serum cholinesterase levels can be a prognostic factor for postoperative recurrence and poor prognosis in patients after curative resection for colorectal cancer, suggesting an important role of cholinesterase in the assessment of nutritional and inflammatory status in cancer patients., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Aim: Frailty assessment in elderly patients is crucial to predict the postoperative course, considering that frailty is highly associated with postoperative complications and mortality. The aim of this study was to evaluate the value of osteopenia as a risk factor for severe postoperative complications in elderly patients who underwent emergency gastrointestinal surgery., Methods: This study comprised 103 elderly patients who underwent emergency gastrointestinal surgery. Osteopenia was diagnosed by measuring bone mineral density, which was calculated as the average pixel density in the midvertebral core at the 11th thoracic vertebra on the preoperative plain computed tomography image. We retrospectively investigated the relationship between preoperative osteopenia and severe postoperative complications (Clavien-Dindo classification ≥III). Univariate and multivariate analyses were performed to evaluate the risk factors for severe postoperative complications., Results: Twenty-three patients (22.3%) developed severe postoperative complications. The optimal cutoff value of bone mineral density for severe postoperative complications was 119.5 Hounsfield unit (HU) and 39 patients (37.9%) were diagnosed with osteopenia. The univariate analysis revealed that the American Society of Anesthesiologists Physical Status of ≥3 ( P  = .0084), hemoglobin levels ( P  = .0026), albumin levels ( P  < .001), sarcopenia ( P  = .015), and osteopenia ( P  < .001) were significantly associated with severe postoperative complications. The multivariate analysis showed that osteopenia ( P  = .014) was an independent risk factor for severe postoperative complications., Conclusion: Osteopenia may be a risk factor for severe postoperative complications in elderly patients after emergency gastrointestinal surgery., (© 2022 The Authors. Annals of Gastroenterological Surgery published by John Wiley & Sons Australia, Ltd on behalf of The Japanese Society of Gastroenterology.)