An uncertainty-based interpretable deep learning framework for predicting breast cancer outcome.

BACKGROUND: Predicting outcome of breast cancer is important for selecting appropriate treatments and prolonging the survival periods of patients. Recently, different deep learning-based methods have been carefully designed for cancer outcome prediction. However, the application of these methods is still challenged by interpretability. In this study, we proposed a novel multitask deep neural network called UISNet to predict the outcome of breast cancer. The UISNet is able to interpret the importance of features for the prediction model via an uncertainty-based integrated gradients algorithm. UISNet improved the prediction by introducing prior biological pathway knowledge and utilizing patient heterogeneity information. RESULTS: The model was tested in seven public datasets of breast cancer, and showed better performance (average C-index = 0.691) than the state-of-the-art methods (average C-index = 0.650, ranged from 0.619 to 0.677). Importantly, the UISNet identified 20 genes as associated with breast cancer, among which 11 have been proven to be associated with breast cancer by previous studies, and others are novel findings of this study. CONCLUSIONS: Our proposed method is accurate and robust in predicting breast cancer outcomes, and it is an effective way to identify breast cancer-associated genes. The method codes are available at: https://github.com/chh171/UISNet .

Circular RNA 0001666 inhibits colorectal cancer cell proliferation, invasion and stemness by inactivating the Wnt/ß-catenin signaling pathway and targeting microRNA-1229.

A previous bioinformatics study suggested that circular RNA 0001666 (circ_0001666) and its target microRNA (miR)-1229 were associated with colorectal cancer (CRC) pathogenesis. However, the role of this interaction in the regulation of CRC cell malignancy remains unclear. Thus, the aim of the present study was to examine the interaction between circ_0001666 and miR-1229, and its effects on CRC cell malignancy. circ_0001666 overexpression or knockdown plasmids were transfected into the HT-29 and HCT-116 cell lines. In addition, in rescue experiments, circ_000166 or miR-1229 overexpression plasmids were transfected into the HT-29 cell line, either alone or in combination. Following transfection, cell proliferation, apoptosis, invasion and the number of CD133+ cells were analyzed. The protein expression level of proteins in the Wnt/ß-catenin pathway was also examined. In both HT-29 and HCT-116 cell lines, circ_0001666 overexpression increased apoptosis, whilst inhibiting cell proliferation and invasion, and reducing the frequency of CD133+ cells. By contrast, circ_0001666 knockdown reduced apoptosis, but increased cell proliferation and the number of CD133+ cells. However, cell invasion remained unaffected. In addition, circ_0001666 expression levels negatively regulated those of miR-1229, whereas miR-1229 expression did not affect circ_0001666, in both the HT-29 and HCT-116 cell lines. Furthermore, a luciferase reporter assay confirmed that miR-1229 directly bound to circ_0001666. In the HT-29 cell line, miR-1229 overexpression activated the Wnt/ß-catenin pathway, and promoted cell proliferation, invasion and stemness, while suppressing cell apoptosis. In addition, miR-1229 overexpression reversed the effects of circ_0001666 overexpression. In conclusion, circ_0001666 suppresses CRC cell proliferation, invasion and stemness by inhibiting the Wnt/ß-catenin signaling pathway by targeting miR-1229, and may represent a potential target for CRC treatment.

Application analysis of omental flap isolation and modified pancreaticojejunostomy in pancreaticoduodenectomy (175 cases).

BACKGROUND: To explore the application value of free omental wrapping and modified pancreaticojejunostomy in pancreaticoduodenectomy (PD). METHODS: The clinical data of 175 patients who underwent pancreaticoduodenectomy from January 2015 to December 2020 were retrospectively analysed. In total, 86 cases were divided into Group A (omental wrapping and modified pancreaticojejunostomy) and 89 cases were divided into Group B (control group). The incidences of postoperative pancreatic fistula and other complications were compared between the two groups, and univariate and multivariate logistic regression analyses were used to determine the potential risk factors for postoperative pancreatic fistula. Risk factors associated with postoperative overall survival were identified using Cox regression. RESULTS: The incidences of grade B/C pancreatic fistula, bile leakage, delayed bleeding, and reoperation in Group A were lower than those in Group B, and the differences were statistically significant (P < 0.05). Group A had an earlier drainage tube extubation time, earlier return to normal diet time and shorter postoperative hospital stay than the control group (P < 0.05). The levels of C-reactive protein (CRP), interleukin-6 (IL-6), and procalcitonin (PCT) inflammatory factors 1, 3 and 7 days after surgery also showed significant. Univariate and multivariate logistic regression analyses showed that a body mass index (BMI) ≥ 24, pancreatic duct diameter less than 3 mm, no isolation of the greater omental flap and modified pancreaticojejunostomy were independent risk factors for pancreatic fistula (P < 0.05). Cox regression analysis showed that age ≥ 65 years old, body mass index ≥ 24, pancreatic duct diameter less than 3 mm, no isolation of the greater omental flap isolation and modified pancreaticojejunostomy, and malignant postoperative pathology were independent risk factors associated with postoperative overall survival (P < 0.05). CONCLUSIONS: Wrapping and isolating the modified pancreaticojejunostomy with free greater omentum can significantly reduce the incidence of postoperative pancreatic fistula and related complications, inhibit the development of inflammation, and favourably affect prognosis.

Fabrication of caseins nanoparticles to improve the stability of cyanidin 3-O-glucoside.

The influence of encapsulation with caseins on the stability of cyanidin 3-O-glucoside (C3G) was investigated. The modified casein nanoparticles (MCs) prepared at pH 5.5 after heated at 80 °C for 30 min was applied to encapsulate C3G. The diameter of nanoparticle (MCs-C3G) was 110 ± 0.31 nm and zeta-potential was -8.83 ± 0.52 mV. The molecular weight of α-casein (32 kDa) and ß-casein (25 kDa) increased along with the encapsulation of C3G. The interactions of MCs with C3G were examined at pH 6.3 by fluorescence spectroscopy and IR spectroscopy. MCs encapsulated C3G mainly via the hydrophobic interaction. The secondary structures of caseins were changed along with the combination of C3G, with a decreasing in α-helix, turn random, and coil structure, as well as increased ß-sheet. In addition, the MCs-C3G interaction appeared to have a positive effect on the thermal, oxidation and photo stability of C3G.

Association among the prognostic nutritional index, completion of adjuvant chemotherapy, and cancer-specific survival after curative resection of stage II/III gastric cancer.

BACKGROUND/OBJECTIVE: To investigate the impact of preoperative immunological and nutritional status, using the prognostic nutritional index (PNI), on completion of planned adjuvant chemotherapy (AC), and the potential additive effects of low PNI and incomplete AC on gastric cancer-specific survival (CSS) after curative resection of stage II/III gastric cancer (GC). METHODS: Medical records of 1288 consecutive stage II/III GC patients who underwent curative resection and planned to receive AC between November 2010 and December 2017 were retrospectively reviewed. The optimal cut-off value of PNI for CSS was determined by X-tile. The independent predictive factors for incomplete AC were identified using univariate and multivariate analyses. Cox regression analyses assessed the association of low PNI, incomplete AC and CSS. RESULTS: Of the 1288 patients, 406 (31.5%) completed at least six cycles of AC within 6 months following initial of AC (complete AC). Low PNI (<43.9, n = 386) was identified to be an independent risk factor for incomplete AC (<6 cycles). Both low PNI and incomplete AC independently predicted poor CSS (hazard ratio (HR): 1.287, 95% confidence interval (CI): 1.058-1.565; HR: 1.667, 95% CI: 1.342-2.071). Further analyses confirmed an additive effect with those with both low PNI and incomplete AC having an even worse CSS. CONCLUSIONS: Low preoperative PNI significantly affects completion of AC. Low PNI and incomplete AC has an additive effect and is associated with even worse outcomes. Further prospective studies are needed to clarify whether perioperative nutrition intervention could improve completion of AC and improve prognosis of GC patients.

Influences of Pretreatment of Carbon on Performance of Carbon Supported Pd Nanocatalyst for Nitrobenzene Hydrogenation.

We in this study prepared carbon supported Pd (Pd/C) nanocatalyst using pretreated carbon by different concentrations of hydrochloric acid, nitric acid, tartaric acid and hydrogen peroxide, respectively. The nanocatalyst was used for hydrogenation of nitrobenzene. The catalytic activity and microstructure of Pd/C catalyst were characterized by High Performance Liquid Chromatography (HPLC), scanning electron microscope (SEM), High power transmission electron microscopy (HTEM) and X-ray Diffraction (XRD). Results showed that the order of catalytic activity was as follows: Pd/C (C4H6O6) < Pd/C (HCI) < Pd/C (HNO3) < Pd/C (H2O2). The values for specific surface area, pore size and pore volume all decreased after pretreatment by HCl and HNO3, and presented a slight increase after pretreatment with H2O2. The dispersion performance of particles in Pd/C catalysts obtained with 25% hydrogen peroxide pretreatment was better and these particles' mean size was 8.0 nm. Pd crystallization degree for catalysts was lower after hydrogen peroxide pretreatment, and the crystalline grains were smaller.

Development and validation of a prognostic nomogram for predicting early recurrence after curative resection of stage II/III gastric cancer.

BACKGROUND: The biological behavior of early recurrence is more invasive and the prognosis is worse in gastric cancer (GC). The risk of early recurrence (ER) for GC in stage II/III has not been reported of which the majority of GC patients are in China. Therefore, it is necessary to analyze the ER of gastric cancer in stage II/III. METHODS: The medical records of 1511 consecutive stage II/III GC patients who received resections were retrospectively reviewed. They were randomly classified into either a development or validation group at a ratio of 7:3. The nomogram was constructed based on prognostic factors using logistic regression analysis and was validated by bootstrap resampling and validation dataset, respectively. Concordance index (C-index) values and calibration curves were used to evaluate the predictive accuracy and discriminatory capability. RESULTS: Three hundred eleven patients experienced ER, accounting for 20.58% of the GC patients investigated. Multivariate logistic regression analysis identified tumors located at upper, middle third, or mixed, a positive lymph node ratio ≥ 0.335, pTNM stage III, lymphocyte count < 1.5 × 109/L, postoperative infection complications and adjuvant chemotherapy < 6 cycles were all independent predictors for ER after curative resection of stage II/III GC. The C-index value obtained for the model was 0.780 (95% CI, 0.747-0.813), and the calibration curves of validation group yielded a C-index value of 0.739 (95% CI, 0.684-0.794), suggesting the practicability of the model. CONCLUSIONS: The nomogram which was developed for predicting ER of stage II/III GC after surgery had good accuracy and was verified through both internal and external validation. The nomogram established can assist clinicians in determining the optimal therapy strategies in counseling, adjuvant treatments, and subsequent follow-up planning.

Development and validation of a prognostic nomogram for predicting post-operative pulmonary infection in gastric cancer patients following radical gastrectomy.

The aim of this retrospective study was to develop and validate a nomogram for predicting the risk of post-operative pulmonary infection (POI) in gastric cancer (GC) patients following radical gastrectomy. 2469 GC patients who underwent radical gastrectomy were enrolled, and randomly divided into the development and validation groups. The nomogram was constructed based on prognostic factors using logistic regression analysis, and was internally and crossly validated by bootstrap resampling and the validation dataset, respectively. Concordance index (C-index) value and calibration curve were used for estimating the predictive accuracy and discriminatory capability. Sixty-five (2.63%) patients developed POI within 30 days following surgery, with higher rates of requiring intensive care and longer post-operative hospital stays. The nomogram showed that open operation, chronic obstructive pulmonary disease (COPD), intra-operative blood transfusion, tumor located at upper and/or middle third and longer operation time (≥4 h) in a descending order were significant contributors to POI risk. The C-index value for the model was 0.756 (95% CI: 0.675-0.837), and calibration curves showed good agreement between nomogram predictions and actual observations. In conclusion, a nomogram based on these factors could accurately and simply provide a picture tool to predict the incidence of POI in GC patients undergoing radical gastrectomy.

Clinicopathological features and prognosis of young gastric cancer patients following radical gastrectomy: a propensity score matching analysis.

The aim of the this retrospective study was to investigate the clinicopathological features of gastric cancer (GC) in young patients and the potential impact of age on the prognosis of patients undergoing radical gastrectomy for GC. From November 2010 to November 2016, 317 young (≤45 years) and 1344 older patients (>45 years) who underwent radical gastrectomy for stage I-III GC were enrolled. The association between age and prognosis was estimated by univariate and multivariate analyses after propensity score matching (PSM). Compared with older patients, the proportion of females, poorly differentiated tumors, good nutritional status, and who received neo-adjuvant and/or adjuvant chemotherapy was significant higher in younger patients, but were less likely to suffer from comorbidities or post-operative complications (all P < 0.05). PSM analysis created 310 pairs of patients. After matching, the long-term survival in younger patients was significantly longer than in older patients at stage I, but similar at stages II and III. However, a young age was not identified as a significant prognostic factor. In conclusion, the prognosis of young GC patients is comparable with and even better than that in older patients after radical gastrectomy when matched for baseline characteristics. Early detection could improve the prognosis of young GC patients.

The effect of preoperative smoking cessation and smoking dose on postoperative complications following radical gastrectomy for gastric cancer: a retrospective study of 2469 patients.

BACKGROUND: To investigate whether smoking adversely affects the short-term outcomes and the potential effects of cigarette dose and preoperative smoking cessation, in patients who underwent gastric cancer (GC) surgery. METHODS: Two thousand, four hundred sixty-nine consecutive patients who underwent radical gastrectomy from November 2010 to July 2018 were included in the present study. Smokers (current or former smokers) were divided into 3 groups in accordance with the duration of smoking cessation preoperatively (≤ 2, 2 to 4, or ≥ 4 weeks) and the cigarette dose (≤ 20, 20 to 40, and ≥ 40 pack-years). The primary endpoint was postoperative complications (surgical site infection, pulmonary problems, bleeding, and others). RESULTS: A total of 1056 patients (42.8%) were smokers. Compared with non-smokers, smokers had significantly higher overall postoperative complications (11.3% vs 7.5%, P = 0.001), and in particular pulmonary problems. Smokers also had more major complications, needing intensive care unit care, and longer postoperative hospital stays. Multivariate analysis confirmed that smoking (odds ratio = 1.506, 95% confidence interval 1.131-2.004, P = 0.005) was an independent risk factor for postoperative complications. Further subgroup analysis identified that there was a positive relationship between the incidence of complications and cigarette dose, and > 20 pack-years was demonstrated to have increased significantly the risk of complications. Smokers who stopped smoking ≥ 4 weeks before surgery had lower pulmonary problems than those with a shorter period of smoking cessation. CONCLUSIONS: Preoperative smoking cessation should be encouraged to reduce postoperative complications in GC patients, especially for heavy smokers.

Screening of important lncRNAs associated with the prognosis of lung adenocarcinoma, based on integrated bioinformatics analysis.

The study aimed to elucidate the mechanisms underlying the occurrence and development of lung adenocarcinoma, and to reveal long non­coding RNA (lncRNA) prognostic factors to identify patients at high risk of disease recurrence or metastasis. Based on extensive RNA sequencing data and clinical survival prognosis information from patients with lung adenocarcinoma, obtained from The Cancer Genome Atlas and the Gene Expression Omnibus databases, a co­expression network of lncRNAs with different expression levels was built using weighted correlation network analysis and MetaDE.ES. The prognostic lncRNAs were identified using the Cox proportional hazards model and Kaplan­Meier survival curves to construct a risk scoring system. The reliability of the system was confirmed in validation datasets. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis was performed on the genes significantly associated with the prognostic lncRNAs using gene set enrichment analysis. A total of 58 and 1,633 differentially expressed lncRNAs and mRNAs were identified, respectively. Considering the module stability, annotation, correlation between modules and clinical factors, and the differential expression levels of lncRNAs, 32 differentially expressed lncRNAs were selected from the brown, red, blue, green and yellow modules for subsequent survival analysis. A signature­based risk scoring system involving five lncRNAs [DIAPH2 antisense RNA 1, FOXN3 antisense RNA 2, long intergenic non­protein coding RNA 652, maternally expressed 3 and RHPN1 antisense RNA 1 (head to head)] was developed. The system successfully distinguished between low­ and high­risk prognostic samples. System effectiveness was further verified using two independent validation datasets. Further KEGG pathway analysis indicated that the target genes of the five prognostic lncRNAs were associated with a number of cellular processes and signaling pathways, including the cell receptor­mediated signaling and cell adhesion pathways. A five­lncRNA signature predicts the prognosis of patients with lung adenocarcinoma. These prognostic lncRNAs may be potential diagnostic markers. The present results may help elucidate the pathogenesis of lung adenocarcinoma.

Radiofrequency ablation with systemic chemotherapy in the treatment of colorectal cancer liver metastasis: a 10-year single-center study.

OBJECTIVE: To retrospectively evaluate the long-term efficacy and safety of radiofrequency ablation (RFA) with systemic chemotherapy (CT) in treatment of solitary liver metastasis after surgery for colorectal cancer (CRC). METHODS: This single-center study was conducted at the Hunan Provincial Cancer Hospital from June 2006 to December 2015 with median follow-up time of 26 months. Percutaneous ultrasound-guided RFA was carried out on eligible patients with solitary liver metastasis after surgery for CRC. After a week, ablation status was confirmed by MRI. Post MRI, all patients received systemic CT with or without molecular-targeted therapy. Survival rate was evaluated and survival curve was constructed with Kaplan-Meier analysis. Log-rank test and Cox regression model were used for univariate and multivariate analysis, respectively, to determine the independent prognostic factors for survival rate. RESULTS: A total of 109 eligible patients (mean age, 53.84±11.71; mean tumor mass diameter, 3.4+2.01 cm) were enrolled in this 10-year study. After RFA, 95 patients achieved complete ablation, and 14 patients achieved partial ablation, with median ablation time of 26 minutes (range: 12-120 minutes). The median survival time required for achieving complete and partial ablation was 56.0 and 19.0 months, respectively (P<.01). After RFA and adjuvant systemic CT, the 1-, 3-, and 5-year survival rates were 92.3%, 50.7%, and 41.6%, respectively, with the median (mean) survival time of 39.0 (56.5) months. Age was the only significant independent prognostic factor with better survival rate observed in patients aged ≥50 years than those aged <50 years (P<0.05). The incidence of complications was minimal (1.8%) with only two cases: one biliary fistula and one liver hemorrhage. CONCLUSION: RFA combination with systemic CT was safe; it showed long-term efficacy in patients with solitary liver metastasis after surgery for CRC and can be a preferred treatment.

Prealbumin and lymphocyte-based prognostic score, a new tool for predicting long-term survival after curative resection of stage II/III gastric cancer.

The aim of this retrospective study was to investigate the prognostic significance of pre-treatment immunological and nutritional statuses in patients with locally advanced gastric cancer (GC), and to use the risk factors to develop a predictive score. A total of 731 patients who underwent gastrectomy for stage II/III GC from November 2010 to December 2015 were recruited into this retrospective study. On the basis of univariate and further multivariate Cox regression analyses, decreased pretreatment lymphocyte count (<1·5×109/litre) and prealbumin concentrations (<180 mg/l) were identified to be independently associated with poorer overall survival (OS) and disease-free survival (DFS). Low albumin concentrations (<33 g/l) were identified as an independent risk factor only for OS, but not for DFS. Thereafter, patients who had a decreased prealbumin concentration and lymphocyte count were given a combination of serum prealbumin concentration and lymphocyte count (Co-PaL) score of 2. Patients with only one or neither of these concentrations were given a Co-PaL score of 1 or 0, respectively. Both the OS and the DFS time were inversely related to the Co-PaL scores, and the differences among the three groups were all significant. In contrast, the prognosis did not differ significantly between patients with good nutrition and those with mild to moderate malnutrition according to the prognostic nutritional index. This study indicated that the simple scoring system could accurately predict the prognosis of patients who underwent gastrectomy for stage II/III GC. The score might be helpful in terms of clinical preoperative decision-making.

Incidence, causes and risk factors for 30-day readmission after radical gastrectomy for gastric cancer: a retrospective study of 2,023 patients.

The aim of this retrospective study was to investigate the incidence of, causes and risk factors for readmission to hospital ≤30 days after discharge of patients who underwent radical gastrectomy for gastric cancer. A total of 2,023 patients underwent radical gastrectomy operations from November 2010 to July 2017 in our hospital. Of these, 60 patients (3.0%) were readmitted within 30 days after their original discharge. The median time span between the index discharge and readmission was 14 days and the median time for readmission was 8 days. The main reasons for readmission were intestinal obstruction (n = 10, 16.7%), intra-abdominal fluid collection (n = 9, 15.0%), abdominal pain (n = 7, 11.7%), nutritional difficulty (n = 4, 6.7%) and anastomotic leakage (n = 4, 6.7%). Five patients (8.3%) required intensive care and 4 patients (6.7%) died from sudden cardiac arrest, gastrointestinal bleeding, sepsis or multiple organ dysfunctions. Multivariate analysis revealed that post-operative complications (Odds Ratio = 5.116, 95% confidence interval: 2.885-9.073, P < 0.001) was the only independent risk factor for readmission. Thus, appropriate strategies on discharge and close follow-ups for these high-risk patients should be drawn up in order to enhance significantly their quality of care.

Incidence, Causes and Risk Factors for 30-Day Unplanned Reoperation After Gastrectomy for Gastric Cancer: Experience of a High-Volume Center.

BACKGROUND: To investigate the incidence, causes and risk factors for unplanned reoperation because of early complications within 30 days of radical gastrectomy for gastric cancer. METHODS: The study cohort comprised 1,948 patients who underwent radical gastrectomy for gastric cancer between November 2010 and April 2017. The incidence, causes and outcomes of unplanned reoperation were examined and the risk factors were identified using univariate and multivariate analyses. RESULTS: In total, 24 patients (1.2%) underwent unplanned reoperations because of early complications after radical gastrectomy. The main causes more frequently requiring reoperation were adhesive intestinal obstruction (eight cases, 33.3%), intra-abdominal bleeding (five cases, 20.8%), wound dehiscence (five cases, 20.8%), anastomotic leakage and intra-abdominal infection (five cases, 20.8%), and iatrogenic common bile duct injury (one case). Multivariate analysis identified that only combined multi-organ resection (odds ratio (OR) = 4.060, 95% confidence interval (CI): 1.645 - 10.023, P = 0.002) was an independent risk factor. Two patients (8.3%) who underwent reoperation died from disseminated intravascular coagulation or sepsis, respectively, which was significantly higher than the remaining 1,924 patients who did not require reoperation (six cases, 0.3%, P < 0.001). Moreover, patients who underwent reoperation experienced higher morbidity rates (37.5% vs. 6.8%, P < 0.001), requiring intensive care (20.8% vs. 2.4%, P < 0.001) and longer postoperative hospital stays (33.6 days vs. 11.0 days, P < 0.001) compared with patients required no reoperation. CONCLUSIONS: Combined multi-organ resection was an independent risk factor for unplanned reoperation following radical gastrectomy. Avoiding multi-organ resection as possible will decrease the likelihood of patients requiring reoperation.

Proteomic analysis of stachyose contribution to the growth of Lactobacillus acidophilus CICC22162.

Stachyose is a functional oligosaccharide, acting as a potential prebiotic for colonic fermentation. To understand the mechanism of how stachyose promotes the growth of probiotic bacterium, we analyzed the differences of the proteome of Lactobacillus acidophilus grown on stachyose or glucose. By a combination of two-dimensional electrophoresis and mass spectrometry analysis, we observed 16 proteins differentially abundant under these two conditions and identified 9 protein spots. Six of these proteins were highly abundant when stachyose was used as the sole carbon source. They included the phosphotransferase system, the energy coupling factor (ECF) transporter and the mannose-6-phosphate isomerase, involved in the uptake and catabolism of stachyose in Lactobacillus acidophilus CICC22162. Supportively, these observations were validated by quantitative RT-PCR analysis and enzymatic activity determination. Positive correlation was found between the content of the proteins and their mRNA levels. Additionally, we explored the recognition mechanism for stachyose binding to the newly identified ECF transporter by MD simulations and free energy analysis. Taken together, these results provide new insights into the mechanism of stachyose in promoting the growth of probiotic bacterium.

Peri-Operative Blood Transfusion Does Not Influence Overall and Disease-Free Survival After Radical Gastrectomy for Stage II/III Gastric Cancer: a Propensity Score Matching Analysis.

OBJECTIVE: Whether peri-operative blood transfusions (BTF) negatively impact long-term survival after gastrectomy for gastric cancer (GC) remains controversial. The aim of this retrospective study was to investigate independent predictive factors of BTF and the potential impact of BTF on overall survival (OS) and disease-free survival (DFS) in patients who underwent radical gastrectomy for stage II/III GC. METHODS: Of 1020 patients who underwent gastrectomy for stage II/III GC from November 2010 to December 2015, 231 (22.6%) patients received BTF. The independent predictive factors of BTF were identified using univariate and multivariate analyses. Cox regression and propensity score matching (PSM) analyses of OS and DFS in patients who received BTF or not were compared. RESULTS: Multivariate analysis revealed that age, pre-operative hemoglobin levels, tumor size, operation time, combined multi-organ resection, and intra-operative blood loss were independent predictive factors for BTF. PSM analysis created 205 pairs of patients. BTF was significantly associated with decreased OS (P = 0.025) and DFS (P = 0.034) in the entire cohort before PSM. After PSM, there was no longer a significant association between BTF and OS (P = 0.850) or DFS (P = 0.880). BTF was not identified as an independent risk factor for OS or DFS by multivariate Cox regression analysis. CONCLUSIONS: The present study revealed that BTF did not influence OS and DFS after radical gastrectomy for stage II/III GC. Worse oncological outcomes were caused by clinical circumstances requiring blood transfusions, including longer operation time and advanced tumor stage, not due to BTF itself.

Impact of peri-operative blood transfusion on post-operative infections after radical gastrectomy for gastric cancer: a propensity score matching analysis focusing on the timing, amount of transfusion and role of leukocyte depletion.

PURPOSE: Allogeneic blood transfusions (BTF) are sometimes inevitable during radical gastrectomy with lymphadenectomy for advanced gastric cancer. The aim of this retrospective study was to investigate the association between BTF and post-operative infections, focusing on the impact of timing, amount of transfusion and the role of leukocyte depletion. METHODS: The study cohort was 2064 patients who underwent gastrectomy for gastric cancer from November 2010 to August 2017. The association between BTF and post-operative infections was estimated by univariate and multivariate analyses after propensity score matching. Subgroup analysis was performed according to the timing and amount of transfusion, and leukocyte depletion or not. RESULTS: Out of a total 2064 patients, 426 (20.6%) received peri-operative BTF. After one-to-one matching, 361 pairs of patients were included for further analysis, of who 68 (9.4%) developed infections. Multivariate analysis identified that an operation time ≥ 240 min, combined multi-organ resection, BTF and BMI ≥ 25 kg/m2 were independent risk factors for post-operative infection. Patients given a high-volume (> 7.5 U), intra-operatively of leukocyte-non-depleted BTF had the highest risk of developing infections clarified by subgroup analysis. CONCLUSION: Infection was the most common complication following gastrectomy for gastric cancer and BTF was identified as an independent risk factor by propensity score matching and multivariate analyses. The timing, amount of transfusion and leukocyte depletion had an impact on the incidence of infection. To decrease infection, BTF should be avoided where possible, particularly during operation, with a large amount and leukocyte-not-depleted blood.

Very High Cycle Fatigue Behavior of a Directionally Solidified Ni-Base Superalloy DZ4.

The effect of casting pores on the very high cycle fatigue (VHCF) behavior of a directionally solidified (DS) Ni-base superalloy DZ4 is investigated. Casting and hot isostatic pressing (HIP) specimens were subjected to very high cycle fatigue loading in an ambient atmosphere. The results demonstrated that the continuously descending S-N curves were exhibited for both the casting and HIP specimens. Due to the elimination of the casting pores, the HIP samples had better fatigue properties than the casting samples. The subsurface crack initiated from the casting pore in the casting specimens at low stress amplitudes, whereas fatigue crack initiated from crystallographic facet decohesion for the HIP specimens. When considering the casting pores as initial cracks, there exists a critical stress intensity threshold ranged from 1.1 to 1.3 MPa m , below which fatigue cracks may not initiate from the casting pores. Furthermore, the effect of the casting pores on the fatigue limit is estimated based on a modified El Haddad model, which is in good agreement with the experimental results. Fatigue life for both the casting and HIP specimens is well predicted using the Fatigue Indicator Parameter (FIP) model.

Effect of Low Cycle Fatigue Predamage on Very High Cycle Fatigue Behavior of TC21 Titanium Alloy.

The effect of low cycle fatigue (LCF) predamage on the subsequent very high cycle fatigue (VHCF) behavior is investigated in TC21 titanium alloy. LCF predamage is applied under 1.8% strain amplitude up to various fractions of the expected life and subsequent VHCF properties are determined using ultrasonic fatigue tests. Results show that 5% of predamage insignificantly affects the VHCF limit due to the absence of precrack, but decreases the subsequent fatigue crack initiation life estimated by the Pairs law. Precracks introduced by 10% and 20% of predamage significantly reduce the subsequent VHCF limits. The crack initiation site shifts from subsurface-induced fracture for undamaged and 5% predamaged specimens to surface precrack for 10% and 20% predamaged specimens in very high cycle region. Furthermore, the predicted fatigue limits based on the El Haddad modified model for the predamaged specimens agree with the experimental results.