[Colorectal cancer with β-catenin protein expression deficiency: a clinicopathological analysis]

Objective: To investigate the clinicopathological features and molecular characteristics of β-catenin-deficient colorectal cancer. Methods: The clinical, pathological and molecular features of 11 colorectal cancers with β-catenin protein loss diagnosed at the 960th Hospital of People's Liberation Army of China, from January 2012 to November 2022 were analyzed. Results: Among the 11 patients, 3 were males and 8 were females. Their age ranged from 43 to 74 years, with the median age of 59 years. Six were in the left colon and 5 were in the right colon. One of the 11 cases had lymph node metastasis, 10 cases were well and moderately differentiated adenocarcinoma, and 1 was mucinous adenocarcinoma. Eight cases were of TNM stage T4, 2 of T1 stage and 1 of Tis stage. β-catenin protein was not detected using immunohistochemistry. Sanger sequencing revealed the presence of fragment-deletion mutation in exon 3 of CTNNB1 gene, resulting in loss of β-catenin protein expression. Conclusion: β-catenin deficiency is present in a small number of colorectal cancers and may be associated with exon 3 mutations of CTNNB1 gene.

[Comparison of short-term safety of two anastomotic techniques when resecting Siewert type II adenocarcinoma of the esophagogastric junction: a multicenter retrospective cohort study]

Objective: In this study, we aimed to compare the short-term safety of two digestive tract reconstruction techniques, laparoscopic total abdominal overlap anastomosis and laparoscopic-assisted end-to-side anastomosis, following radical resection of Siewert Type II adenocarcinoma of the esophagogastric junction. Methods: In this retrospective cohort study, we analyzed relevant clinical data of 139 patients who had undergone radical surgery for Siewert Type II esophagogastric junction adenocarcinoma. These included 89 patients treated at the First Affiliated Hospital of Air Force Medical University from November 2021 to July 2023, 36 patients treated at the First Affiliated Hospital of Xi'an Jiaotong University from December 2020 to June 2021, and 14 patients treated at the Yuncheng Central Hospital in Shanxi Province from September 2021 to November 2022. The group consisted of 107 men (77.0%) and 32 women (23.0%) of mean age 62.5±9.3 years. Forty-eight patients underwent laparoscopic total abdominal overlap anastomosis (overlap group), and 91 laparoscopic-assisted end-to-side anastomosis (end-to-side group). Clinical data, surgical information, pathological findings, postoperative recovery, and related complications were compared between the two groups. Results: There were no significant differences in general clinical data between the overlap and end-to-side anastomosis groups (all P>0.05), indicating comparability. There was no significant difference in operation time (267.2±60.1 minutes vs. 262.8±70.6 minutes, t=0.370, P=0.712). However, the intraoperative blood loss in the overlap group (100 [50, 100] mL) was significantly lower compared to the end-to-side group (100[50, 175] mL, Z=2.776, P=0.005). Compared to the end-to-side group, longer distances between the tumor and distal resection margin proximal(1.7±1.0 cm vs. 1.3±0.9 cm, t=2.487, P=0.014) and the tumor and distal resection margin (9.5±2.9 cm vs. 7.9±3.5 cm, t=2.667, P=0.009) were achieved in the overlap group. Compared with the end-to-side group, the overlap group achieved significantly earlier postoperative ambulation (1.0 [1.0, 2.0] days vs. 2.0 [1.0, 3.0] days, Z=3.117, P=0.002), earlier time to first drink (4.7±2.6 days vs. 6.2±3.0 days, t=2.851, P=0.005), and earlier time to first meal (6.0±2.7 days vs. 7.1±3.0 days, t=2.170, P=0.032). However, the hospitalization costs were higher in the overlap group (113, 105.5±37, 766.3) yuan vs. (97, 250.2±27, 746.9) yuan; this difference is significant (t=2.818, P=0.006). There were no significant differences between the two groups in postoperative hospital stay, total number of lymph nodes cleared, or time to first postoperative flatus (all P>0.05). The incidence of surgery-related complications was 22.9%(11/48) in the overlap group and 19.8% (18/91) in the end-to-side group; this difference is not significant (χ²=0.187, P=0.831). Further comparison of complications using the Clavien-Dindo classification also showed no significant differences (Z=0.406, P=0.685). Conclusions: Both laparoscopic total abdominal overlap anastomosis and laparoscopic-assisted end-to-side anastomosis are feasible for radical surgery for Siewert Type II esophagogastric junction adenocarcinoma. Laparoscopic total abdominal overlap anastomosis achieves longer proximal and distal resection margins and better postoperative recovery; however, end-to-side anastomosis is more cost-effective.

[Relationship between preoperative inflammatory indexes and prognosis of patients with rectal cancer and establishment of prognostic nomogram prediction model]

Objective: To compare the prognostic evaluation value of preoperative neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio (LMR), and systemic immune-inflammation index (SII) in rectal cancer patients. Nomogram survival prediction model based on inflammatory markers was constructed. Methods: The clinical and survival data of 585 patients with rectal cancer who underwent radical resection in the First Affiliated Hospital of Xi'an Jiao tong University from January 2013 to December 2016 were retrospectively analyzed. The optimal cut-off values of NLR, PLR, LMR, and SII were determined by the receiver operating characteristic (ROC) curve. The relationship between different NLR, PLR, LMR and SII levels and the clinic pathological characteristics of the rectal cancer patients were compared. Cox proportional risk model was used for univariate and multivariate regression analysis. Nomogram prediction models of overall survival (OS) and disease-free survival (DFS) of patients with rectal cancer were established by the R Language software. The internal validation and accuracy of the nomograms were determined by the calculation of concordance index (C-index). Calibration curve was used to evaluate nomograms' efficiency. Results: The optimal cut-off values of preoperative NLR, PLR, LMR and SII of OS for rectal cancer patients were 2.44, 134.88, 4.70 and 354.18, respectively. There was statistically significant difference in tumor differentiation degree between the low NLR group and the high NLR group (P<0.05), and there were statistically significant differences in T stage, N stage, TNM stage, tumor differentiation degree and preoperative carcinoembryonic antigen (CEA) level between the low PLR group and the high PLR group (P<0.05). There was statistically significant difference in tumor differentiation degree between the low LMR group and the high LMR group (P<0.05), and there were statistically significant differences in T stage, N stage, TNM stage, tumor differentiation degree and preoperative CEA level between the low SII group and the high SII group (P<0.05). The multivariate Cox regression analysis showed that the age (HR=2.221, 95%CI: 1.526-3.231), TNM stage (Ⅲ grade: HR=4.425, 95%CI: 1.848-10.596), grade of differentiation (HR=1.630, 95%CI: 1.074-2.474), SII level (HR=2.949, 95%CI: 1.799-4.835), and postoperative chemoradiotherapy (HR=2.123, 95%CI: 1.506-2.992) were independent risk factors for the OS of patients with rectal cancer. The age (HR=2.107, 95%CI: 1.535-2.893), TNM stage (Ⅲ grade, HR=2.850, 95%CI: 1.430-5.680), grade of differentiation (HR=1.681, 95%CI: 1.150-2.457), SII level (HR=2.309, 95%CI: 1.546-3.447), and postoperative chemoradiotherapy (HR=1.837, 95%CI: 1.369-2.464) were independent risk factors of the DFS of patients with rectal cancer. According to the OS and DFS nomograms predict models of rectal cancer patients established by multivariate COX regression analysis, the C-index were 0.786 and 0.746, respectively. The calibration curve of the nomograms showed high consistence of predict and actual curves. Conclusions: Preoperative NLR, PLR, LMR and SII levels are all correlated with the prognosis of rectal cancer patients, and the SII level is an independent prognostic risk factor for patients with rectal cancer. Preoperative SII level can complement with the age, TNM stage, differentiation degree and postoperative adjuvant chemoradiotherapy to accurately predict the prognosis of rectal cancer patients, which can provide reference and help for clinical decision.

[Short-term efficacy of robotic-assisted total mesorectal excision with and without lateral lymph node dissection for mid-low advanced rectal cancer: a propensity score matching analysis]

Objective: To evaluate the feasibility, safety and efficacy of robotic-assisted lateral lymph node dissection for mid-low advanced rectal cancer. Methods: A retrospective cohort study was performed. Inclusion criteria: (1) age between 18 and 80 years old; (2) rectal adenocarcinoma diagnosed by pathology; (3) without distant metastasis by preoperative CT or MRI; (4) patients underwent robotic-assisted total mesorectal resection (TME). Exclusion criteria: (1) conversion to open surgery; (2) multiple primary tumors; (3) patients underwent combined multiple organ resection. According to the above criteria, 137 patients undergoing robotic-assisted mid-low rectal cancer resection in the First Affiliated Hospital of Xi'an Jiaotong University from December 2016 to April 2019 were enrolled. Ninety-seven cases underwent robotic-assisted total mesorectal excision (TME group) and 40 underwent robotic-assisted total mesorectal resection with lateral lymph node dissection (LLND) (TME+LLND group, pelvic LLND was performed with neurovascular guidance to retain pelvic autonomic nerves in the order of the left side the first and then the right side). The propensity score matching of 1:1 was performed with R software, based on age, sex, BMI, ASA classification, distance from tumor to the anal verge, preoperative chemoradiotherapy history, preoperative abdominal surgery history, the size of tumors and TNM stage. The operative indicators, postoperative recovery, pathology and postoperative complications within 30 days were compared between the two groups. Results: A total of 72 cases were successfully matched (36 in each group), and there were no statistically significant differences in baseline data between the two groups (all P>0.05). The operation time of TME+LLND group was significantly longer than that of TME group [275.0 (180-405) minutes vs. 220.0 (140-320) minutes, Z=-3.680, P<0.001], while there were no statistically significant differences in blood loss during operation, time to postoperative first flatus, postoperative hospital stay, total hospital cost, tumor differentiation, and distal resection length of margin (all P>0.05). Circumferential resection margin was all negative in both groups. The number of harvested lymph modes in the TME+LLND groups was higher than that in the TME group [26 (18-37) vs. 14 (9-36), Z=-6.407, P<0.001]. In addition, there were no statistically significant differences in postoperative morbidity and Clavien-Dindo classification of complication within 30 days between the two groups (both P>0.05). Conclusions: Although robotic lateral lymph node dissection requires longer operation time, it is a feasible, safe and effective procedure.

Cloning of oligopeptide transport carrier PepT1 and comparative analysis of PepT1 messenger ribonucleic acid expression in response to dietary nitrogen levels in yak () and indigenous cattle () on the Qinghai-Tibetan plateau

The gastrointestinal lumen can directly absorb all di- and tripeptide protein degradation products, and oligopeptide absorption depends on the specific peptide transport carriers, which are located in gastrointestinal epithelial cells on the brush border membrane. Yak () use N more efficiently than cattle do, which implies that yak have a specific mechanism of nonprotein utilization including a peptide absorption mechanism. However, this mechanism has not been clarified. Our objective was to explore whether yak possess any adaptive mechanisms of peptide absorption to survive in the harsh foraging environment of the Qinghai-Tibetan plateau. Twelve castrated males of each of 2 genotypes, yak () and indigenous cattle (), were fed diets of various N levels. The yak PepT1 (yPepT1) cDNA was cloned in omasum epithelial tissue. Our results showed that the full-length yPepT1 cDNA contains 2,805 bp, and a 2,121-bp open reading frame encodes a putative protein of 707 AA residues. The yPepT1 AA sequence identified 5 putative extracellular N-glycosylation sites (Asn, Asn, Asn, Asn, and Asn), 2 putative intracellular protein kinase A sites (Ser and Thr), and 3 intracellular putative protein kinase C sites (Ser, Ser, and Ser). The yPepT1 AA sequence was 99, 95, 86, and 83% identical to PepT1 from cattle (), sheep (), pigs (), and humans (), respectively. The relative PepT1 mRNA expression for indigenous cattle was greater than yak in the rumen, omasum, duodenum, ileum, and liver ( < 0.001); however, it was lower in jejunum tissue ( < 0.01). The relative PepT1 mRNA expression in response to increasing dietary N for both genotypes were linear in the rumen and jejunum ( < 0.10); quadratic or cubic in the reticulum ( < 0.01); linear or quadratic in the duodenum, ileum, and liver ( ≤ 0.01); and linear, quadratic, or cubic in the omasum ( < 0.001). Moreover, there were significant interactions between genotype and dietary N in rumen, reticulum, omasum, duodenum, jejunum, ileum, and liver tissues. In conclusion, the PepT1 profile and expression in gastrointestinal epithelial cells of yak varied from those of cattle, implying that yak have evolved a peptide transport mechanism to adapt the environment of the Qinghai-Tibetan plateau.

Enhancing the rate performance of spherical LiFeBO3/C via Cr doping

Spherical LiFe_1−xCr_xBO₃/C (x = 0, 0.005, 0.008) has been successfully synthesized by ball-milling and spray-drying assisted high-temperature solid-state reaction.

[Morphological studies of extracranial arteries in patients with migraine]

Migraine is a prevalent syndrome, clinically, however, only few pathological materials about this item were available. Since 1980, partial section of extracranial arteries has been performed in patients with intractable migraine, and the cure rate was 91 percent in 46 cases in which 62 arteries were examined pathologically. All of the cases showed pathological findings of fibromuscular dysplasia (FMD). It was considered that FMD is the morphological basis of migraine. The causes of FMD in extracranial arteries may be related with physical damage of vessel wall due to repeated dilation.

In vitro culture and transplantation of encapsulated human fetal islets as an artificial endocrine pancreas

There has been increasing evidence indicating that islet transplantation may offer an ideal endocrine replacement therapy for patients with Type I diabetes mellitus. However, allogenic islets are susceptible to immune rejection. In 1980, Lim and Sun first reported a novel technique of microencapsulation by which pancreatic islets used as transplants could be encapsulated and immunoisolated so as to survive and function for a period of 2-3 weeks. By further improving the biocompatibility of the capsular membrane, Sun's group demonstrated that islet allografts can be protected from rejection for up to 21 months in nonimmunosuppressed, streptozotocin-induced diabetic rats. The biocompatible polymer capsule membrane constitutes a physical barrier to the host's immune system. Permeability of the membrane can be controlled to allow free diffusion of small molecular nutrients, hormones, and metabolites, but exclude lymphocytes, leukocytes, and macromolecular immunoglobulins and complement. Darquy and Reach, in 1985, disclosed the role of the microcapsule membrane in protecting islets from cytotoxic antibodies. Sun's group further demonstrated that the microencapsulation technique effectively protected xenografts of rat islets transplanted into diabetic mice. In a previous report, we described the success of allotransplanted microencapsulated rat islets in treating streptozotocin-induced diabetes in Wistar rats. We now report the in vitro study of human fetal islets microencapsulated within an alginate-polylysine membrane. A preliminary clinical trial of allotransplants for the treatment of insulin-dependent diabetics is also presented.