FHPM: Fine-grained Huge Page Management For Virtualization

As more data-intensive tasks with large footprints are deployed in virtual machines (VMs), huge pages are widely used to eliminate the increasing address translation overhead. However, once the huge page mapping is established, all the base page regions in the huge page share a single extended page table (EPT) entry, so that the hypervisor loses awareness of accesses to base page regions. None of the state-of-the-art solutions can obtain access information at base page granularity for huge pages. We observe that this can lead to incorrect decisions by the hypervisor, such as incorrect data placement in a tiered memory system and unshared base page regions when sharing pages. This paper proposes FHPM, a fine-grained huge page management for virtualization without hardware and guest OS modification. FHPM can identify access information at base page granularity, and dynamically promote and demote pages. A key insight of FHPM is to redirect the EPT huge page directory entries (PDEs) to new companion pages so that the MMU can track access information within huge pages. Then, FHPM can promote and demote pages according to the current hot page pressure to balance address translation overhead and memory usage. At the same time, FHPM proposes a VM-friendly page splitting and collapsing mechanism to avoid extra VM-exits. In combination, FHPM minimizes the monitoring and management overhead and ensures that the hypervisor gets fine-grained VM memory accesses to make the proper decision. We apply FHPM to improve tiered memory management (FHPM-TMM) and to promote page sharing (FHPM-Share). FHPM-TMM achieves a performance improvement of up to 33% and 61% over the pure huge page and base page management. FHPM-Share can save 41% more memory than Ingens, a state-of-the-art page sharing solution, with comparable performance

Knockdown of Linc00515 Inhibits Multiple Myeloma Autophagy and Chemoresistance by Upregulating miR-140-5p and Downregulating ATG14

Background/Aims: The purpose of our experiments was to investigate the targeting relationship of linc00515, miR-140-5p and ATG14 and to explore the roles of linc00515, miR-140-5p and ATG14 in autophagy and chemoresistance of melphalan-resistant multiple myeloma cells. Methods: Plasmids that could interfere with the expression of linc00515 and ATG14 were loaded into myeloma cells, which were cultured with melphalan. MTT assay and flow cytometry analysis were utilized to investigate the effect of linc00515, miR-140-5p and ATG14 on the resistance of myeloma cells. QRT-PCR was used to determine the levels of mRNAs. Western blot was utilized to explore the level of ATG14 and autophagy-related proteins. Dual luciferase assay was utilized to explore the targeting relationship between linc00515, miR-140-5p and ATG14. GFP LC3 fluorescence assay was conducted to study the autophagy of cells. Results: The expression of linc00515 and ATG14 were significantly higher in melphalan-resistant myeloma cells. Knockdown of linc00515 and ATG14 led to decreased autophagy and chemoresistance of melphalan-resistant myeloma cells. The forced expression of miR-140-5p suppressed autophagy and chemoresistance of melphalan-resistant myeloma cells. Conclusion: Linc00515 enhanced autophagy and chemoresistance of melphalan-resistant myeloma by directly inhibiting miR-140-5p, which elevated ATG14 level

Intraoperative and postoperative short-term outcomes of intracorporeal anastomosis versus extracorporeal anastomosis in laparoscopic right hemicolectomy

BackgroundIntracorporeal anastomosis (IA) is a difficult but popular anastomotic approach for reconstruction of digestive tract after laparoscopic right hemicolectomy, which may reduce some limitations faced during extracorporeal anastomosis (EA).MethodsA retrospective review of 78 patients who underwent laparoscopic right hemicolectomy by a veteran surgeon in a high-volume public tertiary hospital, including 50 patients with IA and 28 patients with EA. The intraoperative-related factors and short-term results of the two anastomotic approaches were compared.ResultsThere was no significant difference in demographics and clinical characteristics between the two groups (P>0.05). The intraoperative blood loss was less (P=0.010) and the incision length was shorter (P<0.001) in the intracorporeal group. Postoperative farting time was faster (P=0.005) and postoperative pain score (VAS) was lower (P<0.001) in IA group. Although the anastomotic time of IA was shorter (P<0.001), the operative time of the two groups were similar. And number of lymph nodes harvested, NLR from POD1 to POD3, postoperative hospital stay and overall hospital stay between the two groups were comparable. Except for significant difference in abdominal infection rate, the Clavien-Dindo classification and the incidence of other postoperative complications were not statistically different. Moreover, the morbidity of abdominal infection decreased with time in the IA group (P=0.040).ConclusionIA is a reliable and feasible procedure, which has faster anastomotic time, earlier return of bowel function and superior postoperative comfort of patient, compared to EA. The postoperative complication rate of IA is similar to that of EA, and may be improved with the IA technical maturity of surgeons, which potentially contributes to the development of ERAS

Degradation and mechanism analysis of protein macromolecules by functional bacteria in tobacco leaves

Tobacco, a crop of significant economic importance, was greatly influenced in leaf quality by protein content. However, current processing parameters fail to adequately meet the requirements for protein degradation. Microorganisms possess potential advantages for degrading proteins and enhancing the quality of tobacco leaves, and hold substantial potential in the process of curing. To effectively reduce the protein content in tobacco leaves, thereby improving the quality and safety of the tobacco leaves. In this study, tobacco leaf were used as experimental material. From these, the BSP1 strain capable of effectively degrading proteins was isolated and identified as Bacillus subtilis by 16S rDNA analysis. Furthermore, the mechanisms were analyzed by integrating microbiome, transcriptome, and metabolome. Before curing, BSP1 was applied to the surface of tobacco leaves. The results indicated that BSP1 effectively improves the activity of key enzymes and the content of related substances, thereby enhancing protein degradation. Additionally, protein degradation was achieved by regulating the diversity of the microbial community on the surface of the tobacco leaves and the ubiquitin-proteasome pathway. This study provided new strategies for extracting and utilizing functional strains from tobacco leaves, opening new avenues for enhancing the quality of tobacco leaves