Prognosis of Elderly Patients with Advanced Gastric Cancer without Serosal Invasion

Introduction: The impact of age on the prognosis of patients with gastric cancer is controversial. This study aimed to investigate the clinicopathologic features and prognosis of elderly, advanced gastric cancer patients without serosal invasion compared to their younger counterparts. Materials and Methods: We retrospectively evaluated 43 elderly patients with advanced gastric cancer without serosal invasion. The clinicopathologic findings were compared between the elderly (age >70 years) and young (age <36 years) patients. Results: Significantly higher numbers of elderly patients had tumors with differentiated histology, whereas more young patients had tumors with undifferentiated histology (P < 0.01). Curability (risk ratio, 3.122; confidence interval, 1.242-4.779; P < 0.001) was an independent prognostic factor of survival. The 5-year survival rates were not significantly different between the elderly and the young patients according to the absence of serosal invasion (80.0% vs 77.9%; P = 0.654) and undergoing curative resection (82.0% vs 78.9%; P = 0.312). Meanwhile, among the elderly patients, those who underwent curative resection had a better survival rate than those with non-curative resection (82.0% vs 67.8%; P < 0.001). Conclusion: Elderly patients with advanced gastric cancer without serosal invasion do not have a worse prognosis than their younger counterparts, indicating that age does not impact the prognosis of advanced gastric cancer. The important prognostic factor was whether the patients underwent curative resection

Experimental Investigation of Mechanical Properties of 3D-Printing Built Composite Material

This paper studies the mechanical behaviors of a new composite material manufactured by 3D printing and polymer impregnation techniques. This composite uses 3D-printed plaster with an open-cellular structure as a frame to encapsulate the silicone resin (PDMS) to form a solid body. Because of the vastly different characteristics of the materials that make it up, the composite could have a wide variety of mechanical behaviors. In this study, design of experiment was performed with four-point bending tests using different composition ratios and sizes of open cells to determine the mechanical properties of the composite. These properties include maximum flexural stress (σmax), flexural secant modulus of elasticity (Ef), and toughness indices (I5 and I20). The experimental results show that both Ef and σmax are proportional to the plaster content and the unit cell size, while I20 had an opposite trend. The Ef ranged from 20 to 280 MPa, and σmax ranged from 0.3 to 1.2 MPa for a 25%-75% plaster content and 3.25-6.5 mm cell size. Statistical analysis further confirmed the differences between these cases. This paper has demonstrated the capability of this composite to exert different mechanical properties for functional applications.Mechanical Engineerin

Multiple redundant sequence elements within the fission yeast ura4 replication origin enhancer

BACKGROUND: Some origins in eukaryotic chromosomes fire more frequently than others. In the fission yeast, Schizosaccharomyces pombe, the relative firing frequencies of the three origins clustered 4-8 kbp upstream of the ura4 gene are controlled by a replication enhancer - an element that stimulates nearby origins in a relatively position-and orientation-independent fashion. The important sequence motifs within this enhancer were not previously localized. RESULTS: Systematic deletion of consecutive segments of ~50, ~100 or ~150 bp within the enhancer and its adjacent core origin (ars3002) revealed that several of the ~50-bp stretches within the enhancer contribute to its function in partially redundant fashion. Other stretches within the enhancer are inhibitory. Some of the stretches within the enhancer proved to be redundant with sequences within core ars3002. Consequently the collection of sequences important for core origin function was found to depend on whether the core origin is assayed in the presence or absence of the enhancer. Some of the important sequences in the core origin and enhancer co-localize with short runs of adenines or thymines, which may serve as binding sites for the fission yeast Origin Recognition Complex (ORC). Others co-localize with matches to consensus sequences commonly found in fission yeast replication origins. CONCLUSIONS: The enhancer within the ura4 origin cluster in fission yeast contains multiple sequence motifs. Many of these stimulate origin function in partially redundant fashion. Some of them resemble motifs also found in core origins. The next step is to identify the proteins that bind to these stimulatory sequences

Prognosis of gastric cancer patients with paraaortic lymph node metastasis versus those with distant metastases

Background. It has long been thought that cases of advanced gastric cancer with paraaortic lymph node (PALN) metastasis are impossible to cure. However, several recent reports on the long-term survival of patients with PALN metastasis have reported an increase in the use of gastrectomy with extended lymphadenectomy, involving the dissection of more nodes than those invaded by the tumor, as the standard surgery for advanced gastric cancer. Material and methods. We reviewed the records of 1,015 patients with a confirmed histologic diagnosis of gastric cancer. Among patients with stage IV gastric cancer, 38 had PALN metastasis compared with 233 with peritoneal dissemination and 77 with hepatic metastasis. Results. Based on tumor location, metastasis to the PALNs was more common in upper-third cancer (p < 0.01); hepatic metastasis was more common in well-differentiated adenocarcinoma; and peritoneal dissemination was more common in poorly differentiated cancer (p < 0.001). The 5-year survival in patients with metastasis to the PALNs was significantly higher (28.2%) than in patients with peritoneal dissemination (5.2%) or hepatic metastasis (12.0%) (p < 0.01). Conclusions. The results reveal a better 5-year survival associated with gastric cancer patients with PALN metastasis as compared with those with other distant metastases. Therefore, we recommend performing a more extended lymphadenectomy in patients with gastric cancer, especially those with suspected metastasis to the PALNs.Introduction. It has long been thought that cases of advanced gastric cancer with paraaortic lymph node (PALN) metastasis are impossible to cure. However, several recent reports on the long-term survival of patients with PALN metastasis have reported an increase in the use of gastrectomy with extended lymphadenectomy, involving the dissection of more nodes than those invaded by the tumour, as the standard surgery for advanced gastric cancer. Material and methods. The records of 1,015 patients with a confirmed histologic diagnosis of gastric cancer had been reviewed. Among patients with stage IV gastric cancer, 38 had PALN metastasis compared with 233 with peritoneal dissemination and 77 with hepatic metastasis. Results. Based on tumour location, metastasis to the PALNs was more common in upper-third cancer (p < 0.01); hepatic metastasis was more common in well-differentiated adenocarcinoma, and peritoneal dissemination was more common in poorly differentiated cancer (p < 0.001). The 5-year survival in patients with metastasis to the PALNs was significantly higher (28.2%) than in patients with peritoneal dissemination (5.2%) or hepatic metastasis (12.0%) (p < 0.01). Conclusions. The results reveal a better 5-year survival associated with gastric cancer patients with PALN metastasis as compared with those with other distant metastases. Therefore, performing a more extended lymphadenectomy in patients with gastric cancer is recommended, especially those with suspected metastasis to the PALNs

3D Cell Printed Tissue Analogues: A New Platform for Theranostics

Stem cell theranostics has received much attention for noninvasively monitoring and tracing transplanted therapeutic stem cells through imaging agents and imaging modalities. Despite the excellent regenerative capability of stem cells, their efficacy has been limited due to low cellular retention, low survival rate, and low engraftment after implantation. Three-dimensional (3D) cell printing provides stem cells with the similar architecture and microenvironment of the native tissue and facilitates the generation of a 3D tissue-like construct that exhibits remarkable regenerative capacity and functionality as well as enhanced cell viability. Thus, 3D cell printing can overcome the current concerns of stem cell therapy by delivering the 3D construct to the damaged site. Despite the advantages of 3D cell printing, the in vivo and in vitro tracking and monitoring of the performance of 3D cell printed tissue in a noninvasive and real-time manner have not been thoroughly studied. In this review, we explore the recent progress in 3D cell technology and its applications. Finally, we investigate their potential limitations and suggest future perspectives on 3D cell printing and stem cell theranostics.116Nsciescopu

GaAs droplet quantum dots with nanometer-thin capping layer for plasmonic applications

We report on the growth and optical characterisation of droplet GaAs quantum dots with extremely-thin (11 nm) capping layers. To achieve such result, an internal thermal heating step is introduced during the growth and its role in the morphological properties of the quantum dots obtained is investigated via scanning electron and atomic force microscopy. Photoluminescence measurements at cryogenic temperatures show optically stable, sharp and bright emission from single quantum dots, at near-infrared wavelengths. Given the quality of their optical properties and the proximity to the surface, such emitters are ideal candidates for the investigation of near field effects, like the coupling to plasmonic modes, in order to strongly control the directionality of the emission and/or the spontaneous emission rate, crucial parameters for quantum photonic applications.Comment: 1 pages, 3 figure