Risk factors of postoperative complications and their effect on survival after laparoscopic gastrectomy for gastric cancer.

Background: The association between postoperative complications and long-term survival after laparoscopic gastrectomy (LG) for gastric cancer (GC) remains uncertain. This study aimed to determine the incidence and risk factors of postoperative complications and evaluate their impact on survival outcomes in patients undergoing LG. Methods: A retrospective study was conducted on 621 patients who underwent LG for gastric adenocarcinoma between March 2015 and December 2021. Postoperative complications were classified according to the Clavien-Dindo classification, with major complications defined as Grade III or higher. Logistic regression models with stepwise backward procedure were used to identify risk factors for complications. To assess the impact of postoperative complications on survival, uni- and multi-variable Cox proportional hazard models were used for overall survival (OS) and disease-free survival (DFS). Results: Overall rate of postoperative complications was 17.6% (109 patients); 33 patients (5.3%) had major complications. Independent risk factors for major complications were Charlson comorbidities index (OR [95% CI], 1.87 [1.09-3.12], p-value = 0.018 for each one score increase), and type of anastomosis (OR [95% CI], 0.28 [0.09-0.91], p-value = 0.029 when comparing Billroth II with Billroth I). Multivariable analysis identified major complications as an independent prognostic factor to reduce OS (HR [95% CI], 2.32 [1.02-5.30], p-value = 0.045) and DFS (HR [95% CI], 2.63 [1.37-5.06], p-value = 0.004). Other prognostic factors for decreased survival outcomes were tumor size, presence of invasive lymph nodes, and T4a stage. Conclusions: Major complications rate of LG for GC was approximately 5.3%. Charlson comorbidities index and type of anastomosis were identified as risk factors for major postoperative complications. Major complications were demonstrated to pose adverse impact on survival outcomes.

Stomach-partitioning versus conventional gastrojejunostomy for unresectable gastric cancer with gastric outlet obstruction: A propensity score matched cohort study.

BACKGROUND: Stomach partitioning gastrojejunostomy (SPGJ) was introduced to deal with delayed gastric emptying (DGE). This study aimed to compare the short- and long-term outcomes of SPGJ versus conventional gastrojejunostomy (CGJ). METHOD: This cohort study analyzed 108 patients who underwent gastrojejunostomy for unresectable gastric cancer: 70 patients underwent SPGJ, and 38 patients underwent CGJ between 2018 and 2022. Propensity score-matched (PSM) analysis was used to balance the baseline characteristics. RESULTS: After PSM, there were 26 patients in each group. SPGJ group had significantly lower incidence of DGE (3.8% vs. 34.6%), vomiting (3.8% vs. 42.3%), and prokinetics requirement (11.5% vs. 46.2%). SPGJ group had significantly shorter time to solid diet tolerance (4.1 days vs. 5.7 days) and postoperative hospital stay (7.7 days vs. 9.3 days). There was no significant difference in relapse reinterventions, gastric outlet obstruction (GOO) recurrence, conversion surgery, and survival outcomes. CONCLUSIONS: SGPJ was associated with lower rate of DGE, prokinetics requirement, and shorter time of solid diet tolerance compared to CGJ in the treatment of unresectable gastric cancer patients with GOO.

Multimodal analysis of methylomics and fragmentomics in plasma cell-free DNA for multi-cancer early detection and localization.

Despite their promise, circulating tumor DNA (ctDNA)-based assays for multi-cancer early detection face challenges in test performance, due mostly to the limited abundance of ctDNA and its inherent variability. To address these challenges, published assays to date demanded a very high-depth sequencing, resulting in an elevated price of test. Herein, we developed a multimodal assay called SPOT-MAS (screening for the presence of tumor by methylation and size) to simultaneously profile methylomics, fragmentomics, copy number, and end motifs in a single workflow using targeted and shallow genome-wide sequencing (~0.55×) of cell-free DNA. We applied SPOT-MAS to 738 non-metastatic patients with breast, colorectal, gastric, lung, and liver cancer, and 1550 healthy controls. We then employed machine learning to extract multiple cancer and tissue-specific signatures for detecting and locating cancer. SPOT-MAS successfully detected the five cancer types with a sensitivity of 72.4% at 97.0% specificity. The sensitivities for detecting early-stage cancers were 73.9% and 62.3% for stages I and II, respectively, increasing to 88.3% for non-metastatic stage IIIA. For tumor-of-origin, our assay achieved an accuracy of 0.7. Our study demonstrates comparable performance to other ctDNA-based assays while requiring significantly lower sequencing depth, making it economically feasible for population-wide screening.

Surgical outcomes and quality of life assessment of esophagectomy for cancer with colon conduit via retrosternal route.

PURPOSE: Colon conduit is an alternative to a gastric conduit for esophagectomy in patients that stomach is not available. Surgical technique is complex and has a high risk of morbidities and mortality. Outcomes of patients are still lacking in the literature, thus aims of this study are to evaluate the safety, feasibility and long-term functional outcomes of patients who underwent esophagectomy for cancer with colon conduit via retrosternal route. METHODS: Twenty-six patients underwent operation between August 2016 and June 2021 for malignancies. Minimally invasive esophagectomy and laparotomy were performed in accordance with the 2017 Japan Esophageal Society's guidelines. Colonic interposition was used for esophageal replacement. Outcomes were technical success, complications assessed using Clavien-Dindo classification, and patient's quality of life (QOL) based on EORTC-QOL-OES18 questionnaire. RESULTS: Mean age was 56.0 ± 9.9 years and 21 patients (80.8%) were men. Mean operating time was 432 ± 66 min. Technical success was 100%. The average number of resected lymph nodes was 26 ± 14. Twelve patients (46.2%) experienced postoperative complications: 7/12 were classified as grade I-II, 3/12 as grade III, 1/12 as grade IV, and 1/12 as grade V (death). Patient's QOL improved during the follow-up period with median (25-75th percentiles) global EORTC-QOL-OES18 score was 29 (17-34); 13 (9-21), and 9 (6-16) at 3, 6, and 12 months, respectively. During the follow-up period, there were 4 late complications, 3 lymphatic recurrences, 5 distant metastases, and 6 deaths. CONCLUSIONS: Colon conduit via retrosternal route after esophagectomy is feasible, safe, and could provide acceptable long-term functional outcomes.

Long-Term Outcomes of Open Versus Laparoscopic Distal Gastrectomy for T4a Gastric Cancer: A Propensity Score-Matched Cohort Study.

BACKGROUND: Laparoscopic gastrectomy for advanced gastric cancer (GC) has been applied more frequently worldwide but is still controversial for patients with serosal invasion (T4a). This study compared short- and long-term outcomes of laparoscopic distal radical gastrectomy (LDG) with open distal gastrectomy (ODG) for T4a GC. PATIENTS AND METHODS: We retrospectively studied 472 patients with T4a gastric adenocarcinoma in the lower or middle third of the stomach: 231 underwent LDG and 241 underwent ODG between 2013 and 2020. Short-term outcomes included operative characteristics and complications. Long-term outcomes included overall survival (OS) and disease-free survival (DFS). Propensity score-matched (PSM) analysis was used to adjust for imbalances in baseline characteristics between groups. RESULTS: The PSM strategy resulted in 294 patients (147 in each group). The LDG group had a significantly longer operating time (mean: 200 vs 190 min, p = 0.001) but reduced blood loss (mean: 50 vs 100 ml, p = 0.001). The LDG group had a higher rate of any postoperative complication (23.1% vs 12.2%, p = 0.021) but most were classified as grades I-II according to Clavien-Dindo classification. Grade III-V complications were similar between groups. Five-year OS was 69% versus 60% (p = 0.109) and 5-year DFS was 58% vs 53% (p = 0.3) in LDG and ODG groups, respectively. For tumor size < 5 cm, LDG was better in reduction of blood loss, postoperative hospital length of stay, and OS. CONCLUSIONS: LDG is feasible and safe for patients with T4a GC and is comparable to ODG regarding short- and long-term outcomes. Furthermore, LDG can be a favorable option for T4a GC smaller than 5 cm.

Clinical Outcomes of Laparoscopic Proximal Gastrectomy With Double-Flap Reconstruction for Tumors in the Upper Third of the Stomach.

PURPOSE: Laparoscopic proximal gastrectomy (LPG) has been a standard surgery for early gastric cancer in the upper third of the stomach and large esophagogastric junction gastrointestinal stromal tumor. However, how to reconstruct the stomach after LPG is still debated. This study aimed to evaluate the results of LPG with double-flap reconstruction. METHODS: A retrospective study was performed with 14 patients undergoing LPG with double-flap reconstruction for early gastric cancer or large tumors in the upper third of the stomach from 2018 to 2021. We evaluated postoperative complications, gastroesophageal reflux and the gastric remnant's function using endoscopy in accordance with the Los Angeles and Residue-Gastritis-Bile classifications, and patients' quality of life by the Gastrointestinal Symptom Rating Scale (GSRS) questionnaire. RESULTS: Median age was 54 years and 10 patients were male. There were 7 patients with gastrointestinal stromal tumor, 4 with leiomyoma and 3 with early-stage adenocarcinoma. No patient had major complications or required conversion to open surgery. During a median follow-up period of 24.6 months, 1 patient had late anastomotic stricture, 2 had metastasis, and 1 died. Endoscopic evaluation at 6 and 12 months showed good function of the gastric remnant in most patients. Patients' quality of life improved over time: mean GSRS score was 26.9±12.6, 20.3±7.2, and 18.8±4.2 at 6, 12, and 24 months, respectively. CONCLUSIONS: LPG with double-flap reconstruction is feasible and safe for early gastric cancer or large tumors in the upper third of the stomach. The long-term functional outcomes and patients' quality of life were acceptable.

Role of capsular polysaccharides and lipooligosaccharides in Campylobacter surface properties, autoagglutination, and attachment to abiotic surfaces.

The role of capsular polysaccharides and lipooligosaccharides in cell surface hydrophobicity, surface charge, autoagglutination (AAG), and attachment to abiotic surfaces of three strains of Campylobacter jejuni and one strain of C. coli were investigated. This was achieved by removal of capsular polysaccharides and truncation of lipooligosaccharides core oligosaccharides by inactivation of the kpsE and waaF genes, respectively. The mutants and the wild-type strains were compared after growth under planktonic (broth) and sessile (agar) conditions. Cells grown as planktonic cultures showed a significantly (p<0.05) higher degree of hydrophobicity and AAG activity but differed from their sessile counterparts with respect to surface charge and attachment counts, depending on the strain. These results suggest that prior mode of growth affects the surface properties and attachment of Campylobacter in a strain-dependent manner. There were no significant (p>0.05) differences between the three C. jejuni strains and their ΔkpsE and ΔwaaF mutants with respect to all traits tested. Inactivation of the kpsE gene significantly (p<0.05) reduced the surface charge of the C. coli strain from ∼-10 to ∼-6 mV and increased its AAG activity, while disruption of the waaF gene significantly (p<0.05) increased its surface hydrophobicity by >8° and decreased the numbers of cells attaching to stainless steel and glass by ∼0.5 log/cm². These results suggest that surface polysaccharides may influence the surface properties and attachment to abiotic surfaces of C. coli but not C. jejuni. This suggestion, however, requires further investigation using a larger number of strains of both species.

Role of attachment to surfaces on the prevalence and survival of Campylobacter through food systems.

Campylobacter continues to be one of the bacterial pathogens most frequently associated with human gastrointestinal illness worldwide. Because Campylobacter primarily colonizes the intestines of animals used for food production, food products of animal origin can become contaminated with this pathogen and thus represent a significant risk factor. Despite application of numerous physical and chemical interventions to control Campylobacter during food processing, the high isolation rate of this pathogen from some retail meat products indicates that Campylobacter is able to persist from animal slaughterhouses through food systems. Given the fastidious growth requirements and high susceptibility of this pathogen to environmental conditions, the ability of Campylobacter to attach to food and food-related surfaces is likely to play an important role in food contamination and movement through food systems. This review was compiled to (i) describe how the attachment of Campylobacter to surfaces influences the prevalence and survival of the organism through food systems, (ii) examine the potential factors affecting the ability of Campylobacter to attach to surfaces, and (iii) suggest strategies for controlling this attachment process.

Influence of cell surface hydrophobicity on attachment of Campylobacter to abiotic surfaces.

This work aimed to investigate the influence of physicochemical properties and prior mode of growth (planktonic or sessile culture) on attachment of 13 Campylobacter jejuni strains and 5 Campylobacter coli strains isolated from chicken samples to three abiotic surfaces: stainless steel, glass and polyurethane. Water contact angle and zeta potential measurements indicated that the strains varied with respect to surface hydrophobicity (17.6 ± 1.5 to 53.0 ± 2.3°) and surface charge (-3.3 ± 0.4 to -15.1 ± 0.5 mV). Individual strains had different attachment abilities to stainless steel and glass (3.79 ± 0.16 to 5.45 ± 0.08 log cell cm(-2)) but did not attach to polyurethane, with one exception. Attachment of Campylobacter to abiotic surfaces significantly correlated with cell surface hydrophobicity (P ≤ 0.007), but not with surface charge (P ≥ 0.507). Cells grown as planktonic and sessile culture generally differed significantly from each other with respect to hydrophobicity and attachment (P < 0.05), but not with respect to surface charge (P > 0.05). Principal component analysis (PCA) clustered strains into three groups (planktonic culture) and two groups (sessile culture) representing those with similar hydrophobicity and attachment. Of the four highly hydrophobic and adherent strains, three were C. coli suggesting that isolates with greater hydrophobicity and adherence may occur more frequently among C. coli than C. jejuni strains although this requires further investigation using a larger number of strains. Assignment of pulsed-field gel electrophoresis profiles to PCA groups using Jackknife analysis revealed no overall relationship between bacterial genotypes and bacterial attachment. No relationship between serotype distribution and bacterial attachment was apparent in this study.

Stochasticity of bacterial attachment and its predictability by the extended derjaguin-landau-verwey-overbeek theory.

Bacterial attachment onto materials has been suggested to be stochastic by some authors but nonstochastic and based on surface properties by others. We investigated this by attaching pairwise combinations of two Salmonella enterica serovar Sofia (S. Sofia) strains (with different physicochemical and attachment properties) with one strain each of S. enterica serovar Typhimurium, S. enterica serovar Infantis, or S. enterica serovar Virchow (all with similar physicochemical and attachment abilities) in ratios of 0.428, 1, and 2.333 onto glass, stainless steel, Teflon, and polysulfone. Attached bacterial cells were recovered and counted. If the ratio of attached cells of each Salmonella serovar pair recovered was the same as the initial inoculum ratio, the attachment process was deemed stochastic. Experimental outcomes from the study were compared to those predicted by the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory. Significant differences (P < 0.05) between the initial and the attached ratios for serovar pairs containing S. Sofia S1296a for all different ratios were apparent for all materials. For S. Sofia S1635-containing pairs, 7 out of 12 combinations of serovar pairs and materials had attachment ratios not significantly different (P > 0.05) from the initial ratio of 0.428. Five out of 12 and 10 out of 12 samples had attachment ratios not significantly different (P > 0.05) from the initial ratios of 1 and 2.333, respectively. These results demonstrate that bacterial attachment to different materials is likely to be nonstochastic only when the key physicochemical properties of the bacteria were significantly different (P < 0.05) from each other. XDLVO theory could successfully predict the attachment of some individual isolates to particular materials but could not be used to predict the likelihood of stochasticity in pairwise attachment experiments.

Quantification of acid-base interactions based on contact angle measurement allows XDLVO predictions to attachment of Campylobacter jejuni but not Salmonella.

Acid-base (AB) interactions play the most important role in bacterial attachment to surfaces and can be quantified based on electron donor/electron acceptor data from contact angle measurement (CAM) according to the extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory. It follows that the XDLVO theory could fail to explain attachment numbers if differences in AB interactions between strains are not apparent by CAM. This study aimed to investigate the validity of the above assumptions by comparing empirical data on attachment of six bacterial strains (three strains of Campylobacter jejuni and three strains of Salmonella) to stainless steel and XDLVO theory predictions. A significant difference (P<0.05) in AB interactions, apparent by CAM, between C. jejuni strains allowed prediction of attachment of this species by the XDLVO theory. However, the theory failed to explain the attachment numbers for Salmonella due to similar AB interactions, as established by CAM, between the three Salmonella strains. Qualitative analysis of AB interactions by microbial adhesion to solvents (MATS) revealed a significant difference (P<0.05) in electron donor property between the three Salmonella strains suggesting that these strains may differ with respect to AB interactions. No significant correlation with respect to electron donor property (P=0.502, r(2)=12%) was apparent between CAM and MATS. These data suggest that CAM may not always reflect exactly AB interactions and that the difference in the outcomes from MATS and CAM should be considered when the XDLVO theory is used to predict bacterial attachment to surfaces.

Effect of temperature and contact time on Campylobacter jejuni attachment to, and probability of detachment from, stainless steel.

The effect of temperature and contact time on attachment of six Campylobacter jejuni strains to, and probability of their detachment from, stainless steel were determined. Triplicate stainless steel coupons (SSC) were exposed to C. jejuni cell suspensions at 4, 25, 37, and 55 degrees C for 30 min. An increase in temperature enhanced the numbers of cells of all strains of C. jejuni attaching to stainless steel from approximately 4 log/cm(2) at 4 degrees C to approximately 5 log/cm(2) at 55 degrees C. Cells attached to SSC at 4 and 25 degrees C for 30 min were detached by the successive blotting technique on a series of Campylobacter blood-free selective agar plates. The probability of detachment was significantly (P < 0.05) higher at 4 degrees C (> or = 0.219) than at 25 degrees C (> or = 0.111) for five of the six strains tested, suggesting the strength of attachment was weaker at 4 degrees C than at 25 degrees C for these strains. C. jejuni cells were allowed to attach to SSC at 4 degrees C for 1, 15, 30, 45, 60, 120, 180, 240, and 300 min. The numbers of cells attaching to SSC reached approximately 4 log/cm(2) after 1 min of contact and increased slowly thereafter to approximately 5 log/cm(2) after 300 min of contact. The probability of detachment significantly (P < 0.05) decreased from 0.443 after 1 min to 0.134 after 240 min of contact, indicating bacterial attachment was strengthened over time. These data suggest that to reduce the numbers of adhered cells on processing surfaces, low-temperature and early bacterial detachment procedures should be applied.

Characterization of cellulose production by a Gluconacetobacter xylinus strain from Kombucha.

The aims of this work were to characterize and improve cellulose production by a Gluconoacetobacter xylinus strain isolated from Kombucha and determine the purity and some structural features of the cellulose from this strain. Cellulose yield in tea medium with both black tea and green tea and in Hestrin and Schramm (HS) medium under both static and agitated cultures was compared. In the tea medium, the highest cellulose yield was obtained with green tea (approximately 0.20 g/L) rather than black tea (approximately 0.14 g/L). Yield in HS was higher (approximately 0.28 g/L) but did not differ between static and agitated incubation. (1)H-NMR and (13)C-NMR spectroscopy indicated that the cellulose is pure (free of acetan) and has high crystallinity, respectively. Cellulose yield was improved by changing the type and level of carbon and nitrogen source in the HS medium. A high yield of approximately 2.64 g/L was obtained with mannitol at 20 g/L and corn steep liquor at 40 g/L in combination. In the tea medium, tea at a level of 3 g/L gave the highest cellulose yield and the addition of 3 g/L of tea to the HS medium increased cellulose yield to 3.34 g/L. In conclusion, the G. xylinus strain from Kombucha had different cellulose-producing characteristics than previous strains isolated from fruit. Cellulose was produced in a pure form and showed high potential applicability. Our studies extensively characterized cellulose production from a G. xylinus strain from Kombucha for the first time, indicating both similarities and differences to strains from different sources.