[Safety of patients undergoing radical resection combined with paclitaxel-based hyperthermic intraperitoneal chemotherapy for locally advanced gastric cancer]

Objective: To analyze the safety of paclitaxel-based, hyperthermic, intraperitoneal perfusion chemotherapy (HIPEC) after radical resection of locally advanced gastric cancer. Methods: This was a retrospective cohort study of clinicopathological data of 467 patients with locally advanced gastric adenocarcinoma who had been admitted to the Department of Gastrointestinal Surgery, West China Hospital, Sichuan University between July 2019 and April 2021. Among these patients, 151 had undergone radical resection combined with post-operative paclitaxel-based HIPEC (surgery+HIPEC group) and 316 radical resection alone (surgery group). The adverse perioperative events in study patients were evaluated according to the Common Terminology Criteria for Adverse Events (CTCAE 5.0) published by the U.S. Department of Health and Human Services. Subgroup analysis was performed on patients in the surgery+HIPEC group according to the number of times HIPEC was administered and the incidence of adverse events was compared between subgroups using the χ2 test. Independent risk factors for paclitaxel-based HIPEC-associated adverse events were identified by applying a logistic model. Results: In the surgery+HIPEC group, there were 113 (74.8%) male and 38 (25.2%) female patients of median age 64 (55, 68) years, 18 (11.9%), 79 (52.3%), and 54 (35.8%) of whom had undergone one, two, and three paclitaxel-based HIPEC treatments, respectively, after surgery. The median maximum tumor diameter was 5.0 (3.6, 6.5) cm. In the surgery group, there were 244 (77.2%) male and 72 (22.8%) female patients of median age 63 (54, 68) and the median maximum tumor diameter was 4.0 (3.0, 5.5) cm. In the surgery+HIPEC group, 112 patients (74.2%) had 198 Grade 2 or higher adverse perioperative events, postoperative hypoalbuminemia being the commonest (85 cases, 56.3%), followed by postoperative anemia (50 cases, 33.1%). Compared with the surgery group, the incidences of postoperative hypoalbuminemia (56.3% [85/151] vs. 37.7% [119/316], χ2=14.420, P<0.001), anemia (33.1% [50/151] vs. 22.5% [71/316], χ2=6.030, P=0.014), abdominal pain [7.3% [11/151] vs. 1.6% [5/316], χ2=10.042, P=0.002) and abdominal distension (5.3% [8/151] vs. 1.3% [4/316], χ2=5.123, P=0.024) were all significantly higher in the surgery+HIPEC group. Analysis of the three HIPEC subgroups revealed significant differences in the incidences of postoperative hypoalbuminemia (13/18 vs. 67.1% [53/79] vs. 35.2% [19/54], χ2=12.955, P<0.001) and pulmonary infection (6/18 vs. 6.3% [5/79] vs. 1.9% [1/54], χ2=13.232, P<0.001) between them. Univariate analysis identified body mass index, Borrmann's type and number of HIPEC treatments as associated with perioperative adverse events in the surgery+HIPEC group (P<0.05). However, according to multifactorial logistic analysis, the above factors were not independent risk factors for perioperative adverse events in the surgery+HIPEC group (P>0.05). Conclusions: Paclitaxel-based HIPEC after radical resection significantly increases the risk of postoperative hypoalbuminemia, anemia, abdominal pain, and abdominal distension in patients who have undergone excision of locally advanced gastric cancer. However, increasing the frequency of HIPEC treatments did not significantly increase the risk of paclitaxel-based HIPEC-related adverse events. Moreover, univariate and multivariate analysis did not identify any independent risk factors for paclitaxel HIPEC-related adverse events.

Regulation of Chromatin Modifications through Coordination of Nucleus Size and Epithelial Cell Morphology Heterogeneity

Cell morphology heterogeneity within epithelial collectives is a pervasive phenomenon intertwined with tissue mechanical properties. Despite its widespread occurrence, the underlying mechanisms driving cell morphology heterogeneity and its consequential biological ramifications remain elusive. Here, we investigate the dynamic evolution of epithelial cell morphology and nucleus morphology during crowding, unveiling a consistent correlation between the two. Our investigation reveals a persistent log-normal probability distribution characterizing both cell and nucleus areas across diverse crowding stages and epithelial model systems. We showed that this morphological diversity arises from asymmetric partitioning during cell division and is perpetuated through actomyosin-mediated regulation of cell-nucleus size coordination. Moreover, we provide insights into the impact of nucleus morphology on chromatin dynamics, demonstrating that constraining nucleus area leads to downregulation of the euchromatic mark H3K9ac and upregulation of the heterochromatic mark H3K27me3 through modulation of histone demethylase UTX expression. These findings under-score the significance of cell morphology heterogeneity as a driver of chromatin state diversity, shaping functional variability within epithelial tissues.

Proliferation-driven mechanical compression induces signalling centre formation during mammalian organ development

Localized sources of morphogens, called signalling centres, play a fundamental role in coordinating tissue growth and cell fate specification during organogenesis. However, how these signalling centres are established in tissues during embryonic development is still unclear. Here we show that the main signalling centre orchestrating development of rodent incisors, the enamel knot (EK), is specified by a cell proliferation-driven buildup in compressive stresses (mechanical pressure) in the tissue. Direct mechanical measurements indicate that the stresses generated by cell proliferation are resisted by the surrounding tissue, creating a circular pattern of mechanical anisotropy with a region of high compressive stress at its centre that becomes the EK. Pharmacological inhibition of proliferation reduces stresses and suppresses EK formation, and application of external pressure in proliferation-inhibited conditions rescues the formation of the EK. Mechanical information is relayed intracellularly through YAP protein localization, which is cytoplasmic in the region of compressive stress that establishes the EK and nuclear in the stretched anisotropic cells that resist the pressure buildup around the EK. Together, our data identify a new role for proliferation-driven mechanical compression in the specification of a model signalling centre during mammalian organ development.

[Interpretation of Chinese expert consensus on the surgical treatment for adenocarcinoma of esophagogastric junction(2024 edition)]

Due to the unique nature of its anatomical location, the adenocarcinoma of esophagogastric junction (AEG) has been a subject of controversy and disagreement including its definition, staging, and treatment strategies. Chinse expert Consensus on Surgical Treatment of Adenocarcinoma of Esophagogastric Junction in China (2018 Edition) had been released in September 2018 and had played a pioneering role in unifying thoracic and general surgeons in China on surgical treatment strategies for AEG. Over the past five years, the emergence of several clinical research results on AEG has provided new clinical evidence for the selection of key surgical treatment strategies. Therefore, to further standardize the surgical treatment of AEG in China, Chinese Expert Consensus on Surgical Treatment of Adenocarcinoma of Esophagogastric Junction in China (2024 Edition) was released in 2024 by Chinese expert panel including 25 gastrointestinal surgeons and 24 thoracic surgeons. Based on the highest-level clinical research evidence in recent 5 years, this consensus ultimately formulates 29 recommendations on hotspots and key points on surgical treatment of AEG and summary 5 issues that are still awaiting further exploration. This review will provide a summary and detailed interpretation of the recommendations outlined in this consensus.

Using Ex Vivo Live Imaging to Investigate Cell Divisions and Movements During Mouse Dental Renewal

The continuously growing mouse incisor is emerging as a highly tractable model system to investigate the regulation of adult epithelial and mesenchymal stem cells and tooth regeneration. These progenitor populations actively divide, move, and differentiate to maintain tissue homeostasis and regenerate lost cells in a responsive manner. However, traditional analyses using fixed tissue sections could not capture the dynamic processes of cellular movements and interactions, limiting our ability to study their regulations. This paper describes a protocol to maintain whole mouse incisors in an explant culture system and live-track dental epithelial cells using multiphoton timelapse microscopy. This technique adds to our existing toolbox for dental research and allows investigators to acquire spatiotemporal information on cell behaviors and organizations in a living tissue. We anticipate that this methodology will help researchers further explore mechanisms that control the dynamic cellular processes taking place during both dental renewal and regeneration.

[Clinicopathological characteristics and prognosis of patients with small bowel tumors: A single center analysis of 220 cases]

Objective: To analyze the clinicopathological characteristics and prognosis of patients with small bowel tumors. Methods: This was a retrospective, observational study. We collected clinicopathological data of patients with primary jejunal or ileal tumors who had undergone small bowel resection in the Department of Gastrointestinal Surgery, West China Hospital, Sichuan University between January 2012 and September 2017. The inclusion criteria included: (1) older than 18 years; (2) had undergone small bowel resection; (3) primary location at jejunum or ileum; (4) postoperative pathological examination confirmed malignancy or malignant potential; and (5) complete clinicopathological and follow-up data. Patients with a history of previous or other concomitant malignancies and those who had undergone exploratory laparotomy with biopsy but no resection were excluded. The clinicopathological characteristics and prognoses of included patients were analyzed. Results: The study cohort comprised 220 patients with small bowel tumors, 136 of which were classified as gastrointestinal stromal tumors (GISTs), 47 as adenocarcinomas, and 35 as lymphomas. The median follow-up for all patient was 81.0 months (75.9-86.1). GISTs frequently manifested as gastrointestinal bleeding (61.0%, 83/136) and abdominal pain (38.2%, 52/136). In the patients with GISTs, the rates of lymph node and distant metastasis were 0.7% (1/136) and 11.8% (16/136), respectively. The median follow-up time was 81.0 (75.9-86.1) months. The 3-year overall survival (OS) rate was 96.3%. Multivariate Cox regression-analysis results showed that distant metastasis was the only factor associated with OS of patients with GISTs (HR=23.639, 95% CI: 4.564-122.430, P<0.001). The main clinical manifestations of small bowel adenocarcinoma were abdominal pain (85.1%, 40/47), constipation/diarrhea (61.7%, 29/47), and weight loss (61.7%, 29/47). Rates of lymph node and distant metastasis in patients with small bowel adenocarcinoma were 53.2% (25/47) and 23.4% (11/47), respectively. The 3-year OS rate of patients with small bowel adenocarcinoma was 44.7%. Multivariate Cox regression-analysis results showed that distant metastasis (HR=4.018, 95%CI: 2.108-10.331, P<0.001) and adjuvant chemotherapy (HR=0.291, 95% CI: 0.140-0.609, P=0.001) were independently associated with OS of patients with small bowel adenocarcinoma. Small bowel lymphoma frequently manifested as abdominal pain (68.6%, 24/35) and constipation/diarrhea (31.4%, 11/35); 77.1% (27/35) of small bowel lymphomas were of B-cell origin. The 3-year OS rate of patients with small bowel lymphomas was 60.0%. T/NK cell lymphomas (HR= 6.598, 95% CI: 2.172-20.041, P<0.001) and adjuvant chemotherapy (HR=0.119, 95% CI: 0.015-0.925, P=0.042) were independently associated with OS of patients with small bowel lymphoma. Small bowel GISTs have a better prognosis than small intestinal adenocarcinomas (P<0.001) or lymphomas (P<0.001), and small bowel lymphomas have a better prognosis than small bowel adenocarcinomas (P=0.035). Conclusions: The clinical manifestations of small intestinal tumor are non-specific. Small bowel GISTs are relatively indolent and have a good prognosis, whereas adenocarcinomas and lymphomas (especially T/NK-cell lymphomas) are highly malignant and have a poor prognosis. Adjuvant chemotherapy would likely improve the prognosis of patients with small bowel adenocarcinomas or lymphomas.

Nail mesenchyme: Tipping the hand on regeneration

Digit tip regeneration rebuilds amputated structures in some mammals if the nail organ is preserved. In recently published Cell Reports papers, Castilla-Ibeas et al., Johnson et al., and Mahmud et al. define the patterning function and regenerative capacity of the dorsal nail mesenchyme in this process.

Understanding the development of oral epithelial organs through single cell transcriptomic analysis

During craniofacial development, the oral epithelium begins as a morphologically homogeneous tissue that gives rise to locally complex structures, including the teeth, salivary glands and taste buds. How the epithelium is initially patterned and specified to generate diverse cell types remains largely unknown. To elucidate the genetic programs that direct the formation of distinct oral epithelial populations, we mapped the transcriptional landscape of embryonic day 12 mouse mandibular epithelia at single cell resolution. Our analysis identified key transcription factors and gene regulatory networks that define different epithelial cell types. By examining the spatiotemporal patterning process along the oral-aboral axis, our results propose a model in which the dental field is progressively confined to its position by the formation of the aboral epithelium anteriorly and the non-dental oral epithelium posteriorly. Using our data, we also identified Ntrk2 as a proliferation driver in the forming incisor, contributing to its invagination. Together, our results provide a detailed transcriptional atlas of the embryonic mandibular epithelium, and unveil new genetic markers and regulators that are present during the specification of various oral epithelial structures.

[How to master the clinical study on digestive tract reconstruction in gastric cancer surgery]

Digestive tract reconstruction is extremely important during gastric cancer surgery, which is related to long-tern quality of life of patients. The selection of reconstruction methods and the application of reconstruction techniques are major topics in the field of reconstruction-related study of gastric cancer surgery. The clinical research on digestive tract reconstruction needs to be designed and implemented scientifically to comprehensively evaluate the impact of reconstruction methods on surgical safety, long-term survival outcomes, short- and long-term changes in quality of life, endoscopic mucosal changes and postoperative nutritional status. In addition, health economic analysis is also important and should be considered in reconstruction-related studies. In brief, selection of appropriate gastrointestinal reconstruction methods based on individual characteristics of each gastric cancer patients may be an important direction of clinical trials in the future.

[Comparison of postoperative mid-term and long-term quality of life between Billroth-I gastroduodenostomy and Billroth-II gastrojejunostomy after radical distal gastrectomy in patients with gastric cancer: a cohort study based on a case registry database]

Objective: The pattern of digestive tract reconstruction in radical gastrectomy for gastric cancer is still inconclusive. This study aims to compare mid-term and long-term quality of life after radical gastrectomy for distal gastric cancer between Billroth-I (B-I) and Billroth-II (B-II) reconstruction. Methods: A retrospective cohort study was conducted.Clinicopathological and follow-up data of 859 gastric cancer patients were colected cellected from the surgical case registry database of Gastrointestinal Surgery Center of Sichuan University West China Hospital, who underwent radical distal gastric cancer resection between January 2016 and December 2020. Inclusion criteria: (1) gastric cancer confirmed by preoperative gastroscopy and biopsy; (2) elective radical distal major gastrectomy performed according to the Japanese Society for Gastric Cancer treatment guidelines for gastric cancer; (3) TNM staging referenced to the American Cancer Society 8th edition criteria and exclusion of patients with stage IV by postoperative pathology; (4) combined organ resection only involving the gallbladder or appendix; (5) gastrointestinal tract reconstruction modality of B-I or B-II; (6) complete clinicopathological data; (7) survivor during the last follow-up period from December 15, 2021 to January 15, 2022. Exclusion criteria: (1) poor compliance to follow-up; (2) incomplete information on questionnaire evaluation; (3) survivors with tumors; (4) concurrent malignancies in other systems; (5) concurrent psychiatric and neurological disorders that seriously affected the objectivity of the questionnaire or interfered with patient's cognition. Telephone follow-up was conducted by a single investigator from December 2021 to January 2022, and the standardized questionnaire EORTC QLQ-C30 scale (symptom domains, functional domains and general health status) and EORTC QLQ-STO22 scale (5 symptoms of dysphagia, pain, reflux, restricted eating, anxiety; 4 single items of dry mouth, taste, body image, hair loss) were applied to evaluate postoperative quality of life. In 859 patients, 271 were females and 588 were males; the median age was 57.0 (49.5, 66.0) years. The included cases were divided into the postoperative follow-up first year group (202 cases), the second year group (236 cases), the third year group (148 cases), the fourth year group (129 cases) and the fifth year group (144 cases) according to the number of years of postoperative follow-up. Each group was then divided into B-I reconstruction group and B-II reconstruction group according to procedure of digestive tract reconstruction. Except for T-stage in the fourth year group, and age, tumor T-stage and tumor TNM-stage in the fifth year group, whose differences were statistically significant between the B-I and B-II reconstruction groups (all P<0.05), the differences between the B-I and B-II reconstruction groups in terms of demographics, body mass index (BMI), tumor TNM-stage and tumor pathological grading in postoperative follow-up each year group were not statistically significant (all P>0.05), suggesting that the baseline information between B-I reconstruction group and the B-II reconstruction group in postoperative each year group was comparable. Evaluation indicators of quality of life (EORTC QLQ-C30 and EORTC QLQ-STO22 scales) and nutrition-related laboratory tests (serum hemoglobin, albumin, total protein, triglycerides) between the B-I reconstruction group and B-II reconstruction group in each year group were compared. Non-normally distributed continuous variables were presented as median (Q(1),Q(3)), and compared by using the Wilcoxon rank sum test (paired=False). The χ(2) test or Fisher's exact test was used for comparison of categorical variables between groups. Results: There were no statistically significant differences in all indexes EORTC QLQ-30 scale between the B-I reconstruction group and the B-II reconstruction group among all postoperative follow-up year groups (all P>0.05). The EORTC QLQ-STO22 scale showed that significant differences in pain and eating scores between the B-I reconstruction group and the B-II reconstruction group were found in the second year group, and significant differences in eating, body and hair loss scores between the B-I reconstruction group and the B-II reconstruction group were found in the third year group (all P<0.05), while no significant differences of other item scores between the B-I reconstruction group and the B-II reconstruction group were found in postoperative follow-up of all year groups (P>0.05). Triglyceride level was higher in the B-II reconstruction group than that in the B-I reconstruction group (W=2 060.5, P=0.038), and the proportion of patients with hyperlipidemia (triglycerides >1.85 mmol/L) was also higher in the B-II reconstruction group (19/168, 11.3%) than that in the B-I reconstruction group (0/34) (χ(2)=0.047, P=0.030) in the first year group with significant difference. Albumin level was lower in the B-II reconstruction group than that in the B-I reconstruction group (W=482.5, P=0.036), and the proportion of patients with hypoproteinemia (albumin <40 g/L) was also higher in the B-II reconstruction group (19/125, 15.2%) than that in the B-I reconstruction group (0/19) in the fifth year group, but the difference was not statistically significant (χ(2)=0.341, P=0.164). Other nutrition-related clinical laboratory tests were not statistically different between the B-I reconstruction and the B-II reconstruction in each year group (all P>0.05). Conclusions: The effects of both B-I and B-II reconstruction methods on postoperative mid-term and long-term quality of life are comparable. The choice of reconstruction method after radical resection of distal gastric cancer can be based on a combination of patients' condition, sugenos' eoperience and operational convenience.

[Clinical significance of No.11p posterior lymph nodes dissection in gastric cancer surgery]

Objective: To analyze the association of No.11p posterior lymph node metastasis with clinicopathological features and its prognostic significance in gastric cancer. Methods: A single-center retrospective cohort study was conducted. Clinicopathological data of patients with primary gastric cancers undergoing No.11p posterior lymph node dissection from January 2016 to December 2020 were retrieved from the Database of Gastric Cancer, West China Hospital, Sichuan University. Case inclusion criteria: (1) gastric cancer proved by pathology; (2) radical resection with intraoperative No.11p posterior lymph node dissection; (3) operations performed by the same surgical team; (4) no previous history of other malignant tumors and no concurrent malignant tumors. Those with stump gastric cancer, history of gastrectomy, neoadjuvant chemotherapy, incomplete clinicopathological data and lost to follow-up were excluded. During the operation, the upper edge of the pancreas was retracted forward to expose the area between the upper edge of the pancreas and the splenic vessels. The proximal segment of the splenic artery was skeletonized to remove lymphatic tissue anterior and superior to the splenic artery for No.11p lymph node dissection. For patients with lymphadenopathy in the area between the splenic artery and the splenic vein, dissection was performed. The enlarged lymph nodes were labeled with titanium clips and named as No.11p posterior lymph node. Pathological examination was performed separately after the specimen was isolated. Statistical analysis was performed using R software. Results: A total of 127 gastric cancer patients, who underwent No.11p posterior lymph nodes dissection were included in this study, of which 120 patients without No.11p posterior lymph nodes metastasis (No.11p posterior lymph nodes negative) and 7 patients with No.11p posterior lymph nodes metastasis (No.11p posterior lymph nodes positive). A total of 8 metastatic No.11p posterior lymph nodes were detected in 7 patients, metastasis rate and with a ratio of 5.5% (7/127) and 6.8% (8/127), respectively. In the subgroup analysis of T3-4 stage patients, the metastasis rate and ratio of No.11p posterior lymph nodes were 9.0% (7/78) and 10.7% (8/75), respectively. Compared to negative cases, patients with No.11p posterior lymph nodes metastasis had larger tumor (P=0.002), higher proportion of Borrmann type Ⅲ and Ⅳ tumors (P=0.005), more metastatic lymph nodes (P<0.001), more advanced T stage (P=0.043), N stage (P=0.004) and TNM stage (P=0.015). In survival analysis, patients with No.11p posterior lymph node metastasis had a significantly worse prognosis than those without metastasis after adjusting for TNM stage (hazard ratio=3.009, 95% confidence interval: 1.824-4.964, P<0.001). Conclusions: The No.11p posterior lymph node metastasis in gastric cancer is associated with worse prognosis. For patients of T3-4 stage gastric cancer, No.11p posterior lymph node dissection should be emphasized during radical operation.

FACEts of mechanical regulation in the morphogenesis of craniofacial structures

During embryonic development, organs undergo distinct and programmed morphological changes as they develop into their functional forms. While genetics and biochemical signals are well recognized regulators of morphogenesis, mechanical forces and the physical properties of tissues are now emerging as integral parts of this process as well. These physical factors drive coordinated cell movements and reorganizations, shape and size changes, proliferation and differentiation, as well as gene expression changes, and ultimately sculpt any developing structure by guiding correct cellular architectures and compositions. In this review we focus on several craniofacial structures, including the tooth, the mandible, the palate, and the cranium. We discuss the spatiotemporal regulation of different mechanical cues at both the cellular and tissue scales during craniofacial development and examine how tissue mechanics control various aspects of cell biology and signaling to shape a developing craniofacial organ.

Forced to communicate: Integration of mechanical and biochemical signaling in morphogenesis

Morphogenesis is a physical process that requires the generation of mechanical forces to achieve dynamic changes in cell position, tissue shape, and size as well as biochemical signals to coordinate these events. Mechanical forces are also used by the embryo to transmit detailed information across space and detected by target cells, leading to downstream changes in cellular properties and behaviors. Indeed, forces provide signaling information of complementary quality that can both synergize and diversify the functional outputs of biochemical signaling. Here, we discuss recent findings that reveal how mechanical signaling and biochemical signaling are integrated during morphogenesis and the possible context-specific advantages conferred by the interactions between these signaling mechanisms.

[Effect of standardized surgical treatment and multidisciplinary treatment strategy on the prognosis of gastric cancer patients: report of a single-center cohort study]

Objective: To explore the effect of standardized surgical treatment and multidisciplinary treatment strategy on the treatment outcomes of gastric cancer patients. Methods: A single-center cohort study was carried out. Clinicopathological and long-term follow up data of primary gastric cancer patients were retrieved from the database of Surgical Gastric Cancer Patient Registry (SGCPR) in West China Hospital of Sichuan University. Finally, 4516 gastric cancer patients were included and were divided into three groups according to time periods (period 1 group: exploration stage of standardized surgical treatment, 2000 to 2006, 967 cases; period 2 group: application stage of standardized surgical treatment, 2007 to 2012, 1962 cases; period 3 group: optimization stage of standardized surgical treatment and application stage of multidisciplinary treatment strategy, 2013 to 2016, 1587 cases). Differences in clinical data, pathologic features, and prognosis were compared among 3 period groups. Follow-up information was updated to January 1, 2020. The overall follow-up rate was 88.9% (4016/4516) and median follow-up duration was 51.58 months. Survival curve was drawn by Kaplan-Meire method and compared with log-rank test. Univariate and multivariate analyses were performed by Cox proportional hazards model. Results: There were significant differences among period 1, period 2 and period 3 groups in the rates of D2/D2+ lymphadenectomy [14.4%(139/967) vs. 47.2%(927/1962) vs. 75.4%(1197/1587), χ(2)=907.210, P<0.001], in the ratio of proximal gastrectomy [19.8%(191/967) vs. 16.6%(325/1962) vs. 8.2%(130/1587), χ(2)=100.020, P<0.001], and in the median intraoperative blood loss (300 ml vs. 100 ml vs. 100 ml, H=1126.500, P<0.001). Besides, the increasing trend and significant difference were also observed in the median number of examined lymph nodes among period 1, period 2 and period 3 groups (14 vs. 26 vs. 30, H=987.100, P<0.001). Survival analysis showed that the 5-year overall survival rate was 55.3% in period 1, 55.2% in period 2 and 62.8% in period 3, and significant difference existed between period 3 and period 1 (P=0.004). The Cox proportional hazards model analysis showed that treatment period (period 3, HR=0.820, 95%CI: 0.708 to 0.950, P=0.008), postoperative chemotherapy (HR=0.696, 95%CI: 0.631 to 0.768, P<0.001) and mid-low gastric cancer (HR=0.884, 95%CI: 0.804 to 0.973, P=0.011) were good prognostic factors. Whereas old age (≥65 years, HR=1.189, 95%CI: 1.084 to 1.303, P<0.001), palliative resection (R1/R2, HR=1.538,95%CI: 1.333 to 1.776, P<0.001), large tumor size (≥5 cm, HR=1.377, 95%CI: 1.239 to 1.529, P<0.001), macroscopic type III to IV (HR=1.165, 95%CI: 1.063 to 1.277, P<0.001) and TNM stage II to IV(II/I:HR=1.801,95%CI:1.500~2.162,P<0.001;III/I:HR=3.588, 95%CI: 3.028~4.251, P<0.001; IV/I: HR=6.114, 95%CI: 4.973~7.516, P<0.001) were independent prognostic risk factors. Conclusion: Through the implementation of standardized surgical treatment technology and multidisciplinary treatment model, the quality of surgery treatment and overall survival increase, and prognosis of gastric cancer patients has been improved.

Electronic and transport properties and physical field coupling effects for net-Y nanoribbons

Recently, a new type of quasi-1D graphene-like nanoribbons, periodically embedded with four- and eight- membered rings, has been successfully fabricated, and based on this structure, a novel planar 2D carbon allotrope, the so-called the net-Y, has been proposed. Here, we study various nanoribbons derived from such a 2D monolayer focusing on the structure stability, electronic, and transport properties, especially on the physical field coupling effects of electronic behaviors. Very high stability is predicted for various types of nanoribbons by the calculated binding energy and molecular dynamics simulation. Different edge shapes and widths have a significant influence on their electronic properties. Armchair nanoribbons are always semiconductors, and possess a high carrier mobility. After hydrogen termination, some metallic nanoribbons can become semiconductors or quasi-metals with massless Dirac-fermion behavior. In particular, the electronic properties of ribbons can be effectively modulated by applying strain and electric field. The band gap size and the transition from indirect to direct band gap can be realized upon strain or electric field. These flexibly tunable electronic properties for nanoribbons expand their applications in nanoelectronics and optoelectronics.

A large pool of actively cycling progenitors orchestrates self-renewal and injury repair of an ectodermal appendage

The classical model of tissue renewal posits that small numbers of quiescent stem cells (SCs) give rise to proliferating transit-amplifying cells before terminal differentiation. However, many organs house pools of SCs with proliferative and differentiation potentials that diverge from this template. Resolving SC identity and organization is therefore central to understanding tissue renewal. Here, using a combination of single-cell RNA sequencing (scRNA-seq), mouse genetics and tissue injury approaches, we uncover cellular hierarchies and mechanisms that underlie the maintenance and repair of the continuously growing mouse incisor. Our results reveal that, during homeostasis, a group of actively cycling epithelial progenitors generates enamel-producing ameloblasts and adjacent layers of non-ameloblast cells. After injury, tissue repair was achieved through transient increases in progenitor-cell proliferation and through direct conversion of Notch1-expressing cells to ameloblasts. We elucidate epithelial SC identity, position and function, providing a mechanistic basis for the homeostasis and repair of a fast-turnover ectodermal appendage.

[Comparison of safety and efficacy between proximal gastrectomy and total gastrectomy for upper third gastric cancer: a Meta-analysis]

Objective: To compare the safety and efficacy between proximal gastrectomy and total gastrectomy and to ascertain the optimized procedure for patients with upper third gastric cancer through meta-analysis. Methods: The English literatures about proximal gastrectomy and total gastrectomy for upper third gastric cancer were searched from PubMed, EMBASE, the Cochrane Library and the Web of Science database and then collected. The quality of enrolled studies was independently assessed by two researchers according to the Newcastle-Ottawa Scale for retrospective studies and Jadad scale for RCT studies. The basic information of the literature and related clinical indicators were extracted. The primary endpoints were 5-year overall survival rate and recurrence rate. The secondary endpoints were operative time, intraoperative blood loss, morbidity of postoperative complication, incidence of anastomotic stenosis and incidence of reflux esophagitis. Considering the influence of tumor staging on postoperative clinicopathological features and prognosis, a subgroup analysis was performed on the literatures including cases of early gastric cancer and those including cases of tumor stage I to IV. Statistical analyses were carried out by the "metafor" and "meta" software packages from RevMan 5.3 software and R software (V3.2.4). Results: Twenty-five literatures involving 3667 patients (proximal gastrectomy for 1483, total gastrectomy for 2184) were finally enrolled for analysis, including 24 retrospective studies with ≥ 5 points and 1 RCT with 3 points, and all the literatures were of high quality. A total of 2516 cases of early gastric cancer were enrolled in 18 articles, including 1027 with proximal gastrectomy and 1489 with total gastrectomy. A total of 1151 cases with stage I to IV were enrolled in 7 articles, including 456 in proximal gastrectomy group and 695 in total gastrectomy group. Five-year survival rate was not significantly different for patients with early gastric cancer between the proximal gastrectomy group and total gastrectomy group (OR=1.16, 95% CI: 0.72 to 1.86, P=0.54). Similarly, there was no significant difference for patients with stage I to IV between the proximal gastrectomy group and the total gastrectomy group (OR=1.19, 95% CI: 0.92 to 1.53, P=0.18). Recurrence rate of early gastric cancer patients was not significantly different between the proximal gastrectomy group and the total gastrectomy group (OR=0.40, 95% CI: 0.05 to 3.16, P=0.39).However, the recurrence rate of the proximal gastrectomy group was higher than that of the total gastrectomy group in patients with stage I to IV (OR=1.55, 95% CI: 1.09 to 2.19, P<0.01), whose difference was statistically significant. There was no significant differences in postoperative complication between the groups, both in patients with early gastric cancer, and in those with stage I to IV (both P>0.05). The incidences of postoperative anastomotic stenosis (OR=3.57, 95% CI: 1.82 to 6.99, P<0.01) and reflux esophagitis (OR=2.83, 95% CI: 1.23 to 6.54, P=0.01) in the proximal gastrectomy group were significantly higher than those in the total gastrectomy group in patients with early gastric cancer. Conclusions: There is no significant difference in long-term survival outcomes between total gastrectomy and proximal gastrectomy for upper gastric tumors. However,incidence of anastomotic stenosis and reflux esophagitis, and tumor recurrence rate after total gastrectomy are significantly lower. The total gastrectomy is recommended as the first choice for advanced upper gastric tumor.

[Infrapyloric lymph node dissection in gastric cancer radical surgery under the guidance of mesenteric anatomy theory]

The most common metastasis modality of gastric cancer is the perigastric lymph node metastasis. Complete dissection of regional lymph nodes of the stomach is the core surgical treatment strategy of gastric cancer, and is closely related to the prognosis of gastric cancer patients. Infrapyloric lymph node metastasis is common in gastric cancer,and its incomplete dissection is associated with tumor recurrence. Meanwhile, anatomical variations of vessels and complex mesentery layers of infrapyloric area increase the difficulty of lymphadenectomy during the operation. So, infrapyloric lymph node (No. 6) is an important station. Based on the theory of embryonic development and complete mesogastrium excision, operation across the anatomical space among mesentery layers can ensure en bloc resection of the infrapyloric lymph nodes.

[Efficacy and outcome of transcatheter closure of patent foramen ovale in patients with cryptogenic stroke]

Objective: To investigate the efficacy and outcome of transcatheter patent foramen ovale (PFO) closure in patients with cryptogenic stroke (CS). Methods: Sixty consecutive patients with cryptogenic stroke who undertook transcatheter PFO closure between May 2015 and September 2017 in Beijing Tiantan Hospital were enrolled in this prospective study.Transcranial Doppler (TCD) bubble test was performed and right-left shunt(RLS) was confirmed in all patients.Closure success rate,effective closure rate, complications, recurrence of ischemic stroke and new onset atrial fibrillation were evaluated. Results: A total of 60 patients (42 male,age range 24-68 (47±11)years) were included in the study.PFO size (motionless state) was (1.6±0.6)mm.RLS before closure was graded and 11 patients had moderate RLS and 48 patients had large RLS (include 41 patients who experienced shower or curtain effect).Closure success rate was 100% (60/60).No severe complications were observed.At 6 months,45 patients completed TCD bubble test.Of these, 4 patients suffered from moderate to large residual and thus effective closure rate was 91%(41/45).The mean follow-up period was 2-29 (median 12) months. During the follow-up, only 1 patient experienced recurrent cerebral infarction.New onset atrial fibrillation was not detected. Conclusion: Transcatheter PFO closure is effective,safe and related with a good outcome in reduction of recurrent CS for patients with PFO.

Gastrectomy for gastric carcinoma with situs inversus totalis: case report and literature review

BACKGROUND

Situs inversus totalis (SIT), a rare congenital anomaly, is characterized by a complete mirror image transposition of the thoracic and abdominal viscera. We report the case of a 66-year-old woman with SIT who was diagnosed with gastric antral carcinoma. Curative distal gastrectomy with Billroth-I anastomosis was performed. Description of the case: A 66-year-old woman visited our outpatient department complaining of abdominal pain in the left upper quadrant for about one year. Physical examination revealed that the apex beat was in the right fifth intercostal space, just at the midclavicular line while a soft systolic murmur was audible at the upper right sternal border. The abdominal examination was unremarkable. The preoperative diagnosis was confirmed by gastroscopy and biopsy. Preoperative echocardiogram revealed the presence of dextrocardia and atrial septal defect. Preoperative contrasted computed tomography showed a complete right-left reversal of the thoracic and abdominal organs and thickened wall of gastric antrum without distant metastasis. Laparotomy through a midline incision confirmed the complete mirror-image transposition of the abdominal visceral organs and a 4-cm tumor with serosal involvement at the gastric antrum. Curative distal gastrectomy with D2 lymphadenectomy and Billroth-I anastomosis was performed. The patient had a rapid recovery and was discharged without any complications. The final staging of this case was pT4aN1M0, stage IIIa and she received chemotherapy with the SOX regimen for three cycles. Fifteen months after the operation, the patient is alive without any signs of recurrence.

CONCLUSIONS

The incidence of gastric cancer with SIT is very rare. Appropriate diagnostic modalities are very helpful for the diagnosis and preoperative planning. Gastrectomy with D2 lymphadenectomy in patients with SIT can be performed successfully with sufficient preoperative evaluation, comprehensive knowledge of anatomy, and meticulous surgical manipulation. Caution should be given to the possibility of coexisting cardiopulmonary malformations and synchronous cancers. Hippokratia 2015; 19 (4): 360-362.

A relative shift in cloacal location repositions external genitalia in amniote evolution

The move of vertebrates to a terrestrial lifestyle required major adaptations in their locomotory apparatus and reproductive organs. While the fin-to-limb transition has received considerable attention, little is known about the developmental and evolutionary origins of external genitalia. Similarities in gene expression have been interpreted as a potential evolutionary link between the limb and genitals; however, no underlying developmental mechanism has been identified. We re-examined this question using micro-computed tomography, lineage tracing in three amniote clades, and RNA-sequencing-based transcriptional profiling. Here we show that the developmental origin of external genitalia has shifted through evolution, and in some taxa limbs and genitals share a common primordium. In squamates, the genitalia develop directly from the budding hindlimbs, or the remnants thereof, whereas in mice the genital tubercle originates from the ventral and tail bud mesenchyme. The recruitment of different cell populations for genital outgrowth follows a change in the relative position of the cloaca, the genitalia organizing centre. Ectopic grafting of the cloaca demonstrates the conserved ability of different mesenchymal cells to respond to these genitalia-inducing signals. Our results support a limb-like developmental origin of external genitalia as the ancestral condition. Moreover, they suggest that a change in the relative position of the cloacal signalling centre during evolution has led to an altered developmental route for external genitalia in mammals, while preserving parts of the ancestral limb molecular circuitry owing to a common evolutionary origin.

Heat-induced gene expression as a novel targeted cancer gene therapy strategy

One of the main advantages of gene therapy over traditional therapy is the potential to target the expression of therapeutic genes in desired cells or tissues. To achieve targeted gene expression, we experimented with a new approach based on the long-established phenomenon of the heat shock response. By using the green fluorescence protein as a reporter gene, it was demonstrated that expression of a heterologous gene with a heat shock protein 70 promoter could be elevated to 500-1000-fold over background by moderate hyperthermia (39 degrees C to 43 degrees C) in tissue cultured cells. The heat-induced green fluorescence protein expression was first detectable at 3 h after heating and reached a maximum at 18-24 h. The expression dropped back to baseline within 72 h. In addition, when cells were infected with adenovirus vectors containing the heat-inducible interleukin 12 or tumor necrosis factor alpha genes and then heated (42 degrees C, 30 min), expression was at least 13,600- or 6.8 x 10(5)-fold over background, respectively. Intralesion injection of the interleukin-12-carrying adenovirus vector in a mouse melanoma tumor model caused significant tumor growth delay only with hyperthermia treatment. Our results therefore support heat-induced gene expression as a feasible approach for targeted cancer gene therapy.

Assessment of the antimalarial potential of tetraoxane WR 148999

The antimalarial peroxide, dispiro-1,2,4,5-tetraoxane WR 148999, was synergistic with chloroquine, quinine, mefloquine, and artemisinin against both D6 and W2 clones of Plasmodium falciparum. In consideration of the contrasting antagonism between artemisinin and chloroquine, these drug combination data imply that WR 148999 and artemisinin may not share a common mechanism of action. For Plasmodium berghei-infected mice given oral, subcutaneous, and intraperitoneal doses of WR 148999 ranging from 2 to 1024 mg/kg in the Thompson test, median survival times were 8.8, 11.8, and 27.5 days, respectively, compared to 8 days for control animals. Using subcutaneous administration, WR 148999 had a considerably longer duration of action than did artemisinin against P. berghei. WR 148999 did not significantly inhibit cytochrome P450 isozymes CYP 2C9, 2C19, 2D6, 2E1, or 3A4 (IC50 >500 microM) but did inhibit CYP 1A2 with an IC50 value of 36 microM, suggesting that WR 148999 may be metabolized by the latter CYP isozyme. These results combined with previous observations that formulation strategies and incorporation of polar functional groups in a series of WR 148999 analogs both failed to enhance tetraoxane oral antimalarial activity suggest that oral bioavailability of tetraoxane WR 148999 is more likely a function of extensive first-pass metabolism rather than solubility-limited dissolution.

o-hydroxyphenylacetaldehyde is a hepatotoxic metabolite of coumarin

o-Hydroxyphenylacetaldehyde (o-HPA), the product of coumarin 3, 4-epoxide, was synthesized and its contribution to the hepatotoxic effects of coumarin in the rat was determined. The relative toxicity of coumarin and o-HPA were initially assessed in Chinese hamster ovary K1 (CHO K1) cells, a cell line that does not contain cytochrome P450. In CHO K1 cells, o-HPA-mediated toxicity greatly exceeded that of coumarin. CHO K1 cell viability, determined via the reduction of 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT), was decreased by 95 and 6% in cultures containing o-HPA and coumarin (4 mM), respectively. Coumarin and o-HPA were then incubated in metabolically competent primary rat hepatocyte cultures. Cell viability was determined via the reduction of MTT, and lactic dehydrogenase (LDH) release was used as a measure of cytotoxicity. Concentration-dependent decreases in cell viability and increased LDH release were observed using 0.2 to 0.8 mM o-HPA and coumarin, with coumarin being consistently less toxic than o-HPA. Cell viability was decreased by 11 and 50% at 0.5 mM coumarin or o-HPA, respectively. Hepatocyte LDH release increased 5-fold after a 6-h exposure to 0.8 mM o-HPA, corresponding to a greater than 90% loss of cell viability in these cultures. In contrast, 0.8 mM coumarin decreased cell viability by 60%, an effect likely due to the conversion of coumarin to coumarin epoxide and o-HPA. Furthermore, 3-hydroxycoumarin (0.8 mM), which is not a product of coumarin epoxidation, had no effect on cell viability or hepatocellular LDH release. These studies demonstrate that metabolically active rat hepatocytes convert coumarin into toxic metabolites, and strongly suggest that o-HPA and coumarin 3, 4-epoxide mediate the toxicity of coumarin in rodents in vivo.

Gas chromatographic-mass spectrometric analysis of hydroxylamine for monitoring the metabolic hydrolysis of metalloprotease inhibitors in rat and human liver microsomes

A gas chromatographic-mass spectrometric (GC-MS) method was developed for the analysis of hydroxylamine (HA) in supernatants obtained from liver microsomes. HA monitoring was used to determine the metabolic hydrolysis of two hydroxamic acid-based matrix metalloprotease inhibitors in rat and human liver microsomes. The hydrolysis of the hydroxamic acids to their corresponding carboxylic acids releases HA as a common metabolic product. HA was derivatized to acetone oxime by addition of acetone to the liver microsomal supernatant, followed by direct injection of the supernatant into the GC-MS, with detection of the oxime by selected-ion-monitoring. The method is simple, reproducible, and sensitive for the determination of the hydrolysis of hydroxamic acid compounds, where hydrolysis is the major metabolic pathway. The methodology can be used for rank ordering and selecting hydroxamic acid analogs based on their susceptibility to hydrolysis.

Evaluation of the effects of risedronate on hepatic microsomal drug metabolizing enzyme activities following administration to rats for 14 days: lack of an induction response

Risedronate ([1-hydroxy-2-(3-pyridinyl)-ethylidene[bis]phosphonic acid] monosodium salt) was evaluated for induction of hepatic microsomal drug metabolizing enzymes in male and female Sprague Dawley rats (N = 4/sex/dose group). Main study animals received water (vehicle control), risedronate (0.1, 0.8, 4, or 16 mg/kg/day) or phenobarbital (80 mg/kg/day, positive control) by daily oral gavage for 14 consecutive days. Recovery study animals received water, risedronate (16 mg/kg/day) or phenobarbital (80 mg/kg/day) by daily oral gavage for 14 consecutive days and then were maintained drug-free for 14 days to evaluate the reversibility of any observed effects. At the conclusion of each study the animals were sacrificed, the liver removed, weighed and the microsomal subcellular fraction prepared. The hepatic microsomal fraction was then evaluated for protein content, cytochrome P450, and the activities of aniline hydroxylase, aminopyrine N-demethylase, ethoxycoumarin O-deethylase and p-nitrophenol UDP-glucuronosyltransferase. Risedronate was well tolerated during the dosing phase of the study as evidenced by clinical observations, body weight gain and food consumption which were not significantly different from the vehicle controls. Risedronate did not significantly increase (P > 0.05) liver weight, liver/body weight ratio, protein content, P450, aniline hydroxylase, aminopyrine N-demethylase, ethoxycoumarin O-deethylase or p-nitrophenol UDP-glucuronosyltransferase in rats of either sex when compared to vehicle controls. As expected, the hepatic microsomal enzyme inducer phenobarbital significantly increased (P < 0.05) liver weight, liver/body weight ratio, protein content (males only), P450, aniline hydroxylase (males only), aminopyrine N-demethylase (males only), ethoxycoumarin O-deethylase and p-nitrophenol UDP-glucuronosyltransferase in rats relative to vehicle controls. Following the 14 day drug-free recovery period the induction parameters increased by phenobarbital reversed to vehicle control levels. The results obtained in this well controlled study indicate that risedronate is not an inducer of hepatic microsomal drug metabolizing enzymes in the rat.

Characterization of the effects of tebufelone on hepatic cytochromes P450 in the beagle dog

Tebufelone (1-[3,5-bis(1,1-dimethylethyl)-4-hydroxy-phenyl]-hex-5-yne-1-one) is an investigational ditertiary butylphenol nonsteroidal anti-inflammatory drug. The purpose of the present study was to assess the effects of tebufelone on hepatocyte ultrastructure and hepatic cytochromes p450 (P450s) in the beagle dog after 2 weeks of oral administration at dose levels of 0, 5, 15, 50, and 100 mg/kg/day (N = 1/sex/dose level). Hepatic tissue was obtained at necropsy for histologic, ultrastructural, and biochemical evaluation. Hepatocellular hypertrophy was observed in only a single tebufelone-treated dog (50 mg/kg). Electron microscopic evaluation, however, revealed marked dose-dependent increases in smooth endoplasmic reticulum in all of the tebufelone treatment groups. Biochemical indicators suggested that tebufelone produced mixed effects on hepatic P450s. p-Nitroanisole O-demethylase and, to a greater extent, ethoxyresorufin O-deethylase activities were decreased with increasing tebufelone dose. The precise mechanism by which tebufelone decreased ethoxyresorufin O-deethylase activity in dogs in unknown, but it was not by competitive inhibition, P450 inactivation, or reduced CYP1A expression. Tebufelone treatment increased NADPH-dependent cytochrome c reductase, total P450, and indicators of CYP2B11 (chloramphenicol covalent binding and immunochemically determined 2B11) and CYP3A12 (erythromycin N-demethylase, triacetyloleandomycin spectral complex formation, testosterone 6 beta-hydroxylase, and immunochemically determined 3A12). The largest increase in the 2B11 and 3A12 markers occurred in the 50 or 100 mg/kg treatment groups. The greatest increase in CYP2B11 markers produced by tebufelone treatment ranged from 2- to 3-fold, whereas the increase in CYP3A12 markers ranged from 5- to 10-fold. The changes in hepatic ultrastructure and increases in CYP2B11 and CYP3A12 markers produced by tebufelone in dogs are similar to that reported for phenobarbital.