Efficient arachidonic acid-rich oil production by Mortierella alpina through a three-stage fermentation strategy

A three-stage fermentation strategy was designed for efficient arachidonic acid (ARA)-rich oil production by Mortierella alpina. The process at different stages by changing the components of medium was investigated. In the first stage, mycelia were inoculated in a nutrient-rich medium for rapid propagation. In the second stage, mycelia were collected and then cultivated in glucose solution to achieve high cellular lipid contents. In the third stage, mycelia were cultured in a glucose-absent medium to obtain rapid ARA accumulation. Using this fermentation strategy, high dry cell weight, lipid, and ARA concentration reached 41.6, 26.6, and 11.4 g/L, respectively. The results demonstrated that mycelia propagation, lipid biosynthesis, and ARA accumulation process can be significantly spatially separated, allowing further optimization to improve the efficiency of each stage. This was the first report of using a three-stage fermentation strategy for ARA-rich oil production, and it could be applied to other similar oleaginous microorganisms to obtain high related polyunsaturated fatty acids accumulation.     

Increased expression of Tim-3 and its ligand Galectin-9 in rat allografts during acute rejection episodes

The aim of the study is to elucidate the profiles of T-cell immunoglobulin and mucin domain-3 (Tim-3) and its ligand Galecin-9 in acute pulmonary rejection by using a rat model of lung transplantation. Left lung grafts retrieved from Lewis or Fisher 344 rats were orthotopically transplanted into Lewis recipients without any immunosuppressions; the grafts were harvested at day 3, 7 or 10 after transplantation. The grade of acute rejection was histopathologically evaluated. Tim-3, Galectin-9, immune antigen and related cytokines expression were assessed with immunological techniques and real-time polymerase chain reaction (RT-PCR), respectively. Then, our results showed that Tim-3 and its ligand Galectin-9 were markedly up-regulated at protein and mRNA levels in allografts compared with syngrafts. Meanwhile, the decreased CD4/CD8 ratio was associated with acute rejection occurring and Tim-3 expression on CD4⁺ and CD8⁺ T cells in allografts was increased. Therefore, our study firstly described that enhanced Tim-3 and its ligand Galectin-9 in allografts might play an important role in the pathogenesis of rat lung transplant rejection, implying new valuable markers for detecting acute allograft rejection.     

MiR‐671‐5p plays a promising role in restraining osteosarcoma cell characteristics through targeting TUFT1

The aim of our study was to explore the roles of miR‐671‐5p in mediating biological processes of osteosarcoma (OS) cells and clinical implications. On the basis of the OS samples acquired from the GEO database, the expression difference and overall survival analyses of miR‐671‐5p and TUFT1 were determined. The expression of MiR‐671‐5p was verified using OS cell lines. 3‐(4,5‐Dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide, wound‐healing, and Transwell assays were respectively carried out to probe whether miR‐671‐5p regulated OS cell vitality, migration, and invasion. The expression of miR‐671‐5p was downregulated in OS tissues and cell lines. High expression of MiR‐671‐5p blocked OS cell growth, migration, and invasion. TUFT1 was predicted and validated as the target of miR‐671‐5p in OS cells using in silico analysis and luciferase reporter assays. Forced expression of TUFT1 reversed the suppressive influence of miR‐671‐5p on cell viability, migration, and invasion of OS cells. Moreover, the low expression of miR‐671‐5p and the high expression of TUFT1 led to poor prognosis. Taken together, targeting miR‐671‐5p/TUFT1 may be a promising strategy for treating OS.     

Comparative study of sulfur utilization and speciation transformation of two elemental sulfur species by thermoacidophilic Archaea Acidianus manzaensis YN-25

The sulfur utilization and speciation transformation of two elemental sulfur species (orthorhombic α-S₈ and amorphous μ-S) by thermoacidophilic Archaea strain Acidianus manzaensis YN-25 was comparatively studied. The results of cell growth and sulfur oxidation behavior showed that A. manzaensis cultured on μ-S grew faster (about 24 h earlier to reach stationary phase than that on α-S₈) and produced more H⁺ and SO₄^2?. Results of scanning electron microscopy indicated that the surfaces of μ-S and α-S₈ were differently bio-corroded by A. manzaensis into loose porosities and pits, respectively. Fourier transform-infrared spectroscopy analysis indicated both μ-S and α-S₈ were adsorbed by the cells. X-ray diffraction and Raman spectra analysis indicated that μ-S was mostly converted into α-S₈ after A. manzaensis cell growth while α-S₈ was not transformed into a different allotrope. The fitted result of sulfur K edge XANES spectra further showed that the μ-S after growth of A. manzaensis were composed of 92.1% α-S₈ and 7.9% μ-S, while no change in composition for α-S₈ was found.     

The GTPase-Activating Protein Rga1 Interacts with Rho3 GTPase and May Regulate Its Function in Polarized Growth in Budding Yeast

In budding yeast, Rga1 negatively regulates the Rho GTPase Cdc42 by acting as a GTPase-activating protein (GAP) for Cdc42. To gain insight into the function and regulation of Rga1, we overexpressed Rga1 and an N-terminally truncated Rga1-C538 (a.a. 538-1007) segment. Overexpression of Rga1-C538 but not full-length Rga1 severely impaired growth and cell morphology in wild-type cells. We show that Rga1 is phosphorylated during the cell cycle. The lack of phenotype for full-length Rga1 upon overexpression may result from a negative regulation by G1-specific Pho85, a cyclin-dependent kinase (CDK). From a high-copy suppressor screen, we isolated RHO3, SEC9, SEC1, SSO1, SSO2, and SRO7, genes involved in exocytosis, as suppressors of the growth defect caused by Rga1-C538 overexpression. Moreover, we detected that Rga1 interacts with Rho3 in two-hybrid and bimolecular fluorescence complementation (BiFC) assays. Rga1 preferentially interacts with the GTP-bound form of Rho3 and the interaction requires the GAP domain and additional sequence upstream of the GAP domain. Our data suggest that the interaction of Rga1 with Rho3 may regulate Rho3’s function in polarized bud growth.     

Molecular Epidemiology of EGFR Mutations in Asian Patients with Advanced Non-Small-Cell Lung Cancer of Adenocarcinoma Histology – Mainland China Subset Analysis of the PIONEER study

Epidermal growth factor receptor (EGFR) mutations are the strongest response predictors to EGFR tyrosine kinase inhibitors (TKI) therapy, but knowledge of the EGFR mutation frequency on lung adenocarcinoma is still limited to retrospective studies. The PIONEER study (NCT01185314) is a prospective molecular epidemiology study in Asian patients with newly diagnosed advanced lung adenocarcinoma, aiming to prospectively analyze EGFR mutation status in IIIB/IV treatment-naïve lung adenocarcinomas in Asia. We report the mainland China subset results. Eligible patients (≥20 yrs old, IIIB/IV adenocarcinoma and treatment-naïve) were registered in 17 hospitals in mainland China. EGFR was tested for mutations by amplification refractory mutation system using biopsy samples. Demographic and clinical characteristics were collected for subgroup analyses. A total of 747 patients were registered. Successful EGFR mutation analysis was performed in 741, with an overall mutation rate of 50.2%. The EGFR active mutation rate is 48.0% (with 1.3% of combined active and resistance mutations). Tobacco use (>30 pack-year vs. 0–10 pack-year, OR 0.27, 95%CI: 0.17–0.42) and regional lymph nodes involvement (N3 vs. N0, OR 0.47, 95%CI: 0.29–0.76) were independent predictors of EGFR mutation in multivariate analysis. However, even in regular smokers, the EGFR mutation frequency was 35.3%. The EGFR mutation frequency was similar between diverse biopsy sites and techniques. The overall EGFR mutation frequency of the mainland China subset was 50.2%, independently associated with the intensity of tobacco use and regional lymph nodes involvement. The relatively high frequency of EGFR mutations in the mainland China subset suggest that any effort to obtain tissue sample for EGFR mutation testing should be encouraged.     

Safety and Efficacy of Thermal Ablation for Small Renal Masses in Solitary Kidney: Evidence from Meta-Analysis of Comparative Studies

Objective

To evaluate comparative renal functional preservation, perioperative and oncologic outcomes, and complications of thermal ablation (TA) versus partial nephrectomy (PN) in management of Small renal masses (SRMs) in solitary kidney.

Methods and Findings

Medline, Embase, Web of Science and the Cochrane Library were systematically searched. A meta-analysis for comparative studies comparing TA with PN was performed. According to predefined inclusion criteria, seven datasets were identified from 8 observational studies including a total of 628 patients. Cumulated data showed the changes of creatinine (p=0.02) and estimated glomerular filtration rate (eGFR) (p<0.0001) in TA arm were significantly less than these in PN arm. Significantly less new-set chronic kidney disease (CKD) was observed in TA group (p=0.04). In terms of postoperative dialysis rate, the difference favoring TA was also noted, though there is no statistical significance (p=0.09). With regard to perioperative outcomes, our data demonstrated that patients who underwent TA had significantly shorter operation time (p=0.002), less blood loss (p<0.0001), shorter length of stay (p<0.00001), and less transfusion rate (p=0.01) than those underwent PN. In addition, patients underwent TA suffered less intra- and postoperative complications (p=0.007, p<0.00001; respectively). With regard to oncologic outcomes, disease-free survival (DFS) (p<0.00001) and cancer-specific survival (CSS) (p=0.01) in the PN arm were significantly better than these of the TA arm. But, TA yielded a comparable overall survival to PN (p=0.40). Sensitivity analyses led to very similar results with overall results, and confirmed its stability.

Conclusions

Our analysis indicates that PN have advantage in controlling cancer recurrence. However, TA is associated with significantly better renal functional preservation and perioperative outcomes, and less complications without increasing overall death. Our data suggest that indication for TA may be extended to select younger, healthier patients who desire a much less invasive therapeutic option.