Siderophore for Lanthanide and Iron Uptake for Methylotrophy and Plant Growth Promotion in Methylobacterium aquaticum Strain 22A

Methylobacterium and Methylorubrum species are facultative methylotrophic bacteria that are abundant in the plant phyllosphere. They have two methanol dehydrogenases, MxaF and XoxF, which are dependent on either calcium or lanthanides (Lns), respectively. Lns exist as insoluble minerals in nature, and their solubilization and uptake require a siderophore-like substance (lanthanophore). Methylobacterium species have also been identified as plant growth-promoting bacteria although the actual mechanism has not been well-investigated. This study aimed to reveal the roles of siderophore in Methylobacterium aquaticum strain 22A in Ln uptake, bacterial physiology, and plant growth promotion. The strain 22A genome contains an eight-gene cluster encoding the staphyloferrin B-like (sbn) siderophore. We demonstrate that the sbn siderophore gene cluster is necessary for growth under low iron conditions and was complemented by supplementation with citrate or spent medium of the wild type or other strains of the genera. The siderophore exhibited adaptive features, including tolerance to oxidative and nitrosative stress, biofilm formation, and heavy metal sequestration. The contribution of the siderophore to plant growth was shown by the repressive growth of duckweed treated with siderophore mutant under iron-limited conditions; however, the siderophore was dispensable for strain 22A to colonize the phyllosphere. Importantly, the siderophore mutant could not grow on methanol, but the siderophore could solubilize insoluble Ln oxide, suggesting its critical role in methylotrophy. We also identified TonB-dependent receptors (TBDRs) for the siderophore-iron complex, iron citrate, and Ln, among 12 TBDRs in strain 22A. Analysis of the siderophore synthesis gene clusters and TBDR genes in Methylobacterium genomes revealed the existence of diverse types of siderophores and TBDRs. Methylorubrum species have an exclusive TBDR for Ln uptake that has been identified as LutH. Collectively, the results of this study provide insight into the importance of the sbn siderophore in Ln chelation, bacterial physiology, and the diversity of siderophore and TBDRs in Methylobacterium species

Methanol bioeconomy: promotion of rice crop yield in paddy fields with microbial cells prepared from natural gas‐derived C 1 compound

微生物やその細胞壁成分の葉面散布による酒米の増収に成功 --メタノールを原料に生産した微生物製剤を出穂後1度の散布で--. 京都大学プレスリリース. 2020-12-11.Methylotrophs, which can utilize methanol as a sole carbon source, are promising microorganisms to be exploited in a methanol‐based bioeconomy, in which a variety of useful compounds are biotechnologically produced from natural gas‐derived methanol. Pink‐pigmented facultative methylotrophs (PPFMs) are common plant phyllospheric bacteria and are known to enhance seedling growth and total biomass of various plants. However, improvement of crop yield by inoculation of PPFMs at the field level has not been well investigated. We herein describe improvement of crop yield of several rice cultivars by foliar spraying of PPFMs. After selection of PPFM strains and rice cultivars by the in vitro seedling growth test, we further conducted paddy field experiments. The crop yield of the sake‐brewing rice Oryza sativa cultivar Hakutsurunishiki was reproducibly improved in a commercial paddy field for over a 5‐year period. A one‐time foliar spray of PPFM cells (living or killed) or a cell wall polysaccharide fraction, after the heading date, acted in the phyllosphere and effectively improved crop yield. Our results show that the established process with PPFMs is feasible for improvement of food production in the methanol bioeconomy

Interleukin-8 in bronchoalveolar lavage fluid of patients with diffuse panbronchiolitis or idiopathic pulmonary fibrosis

This study was designed to clarify the contribution of IL-8 as a specific neutrophil chemotactic factor in the human respiratory tract in various pulmonary diseases. The neutrophil chemotactic activity(NCA), neutrophil counts and IL-8 concentration in the bronchoalveolar lavage fluid (BALF) obtained from normal volunteers (NV), control patients (CP), patients with diffuse panbronchiolitis (DPB) and patients with idiopathic pulmonary fibrosis (IPF) were examined. Neutrophil counts, NCA and IL-8 concentration in BALF obtained from patients with DPB or IPF was significantly higher than that from NV or CP. The IL-8 concentration correlated with neutrophil count and also correlated with NCA in BALF from patients with IPF, whereas there was no correlation between these factors in BALF from DPB. These results suggest that the contribution of IL-8 to neutrophil accumulation of the lower respiratory tract is different between IPF and DPB

Autoantibodies to IL-1α in sera from rapidly progressive idiopathic pulmonary fibrosis

To clarify the clinical significance of autoantibodies to interleukin-1α (IL-1α autoantibodies) in rapidly progressive idiopathic pulmonary fibrosis ( IPF ), we measured the level of IL-1α autoantibodies in serum of 11 patients on the first hospital day, when patients were admitted due to severe symptoms, and on the 21st hospital day. IL-1α autoantibodies in serum were measured using radioimmunoassay, and the limitation of this assay for IL-1α autoantibodies was 5 ng/ml. These antibodies were detected in 5 of 11 patients on the first hospital day. On the 21st hospital day, these antibodies were detected in all patients, and its level was increased compared with that on the first hospital day. IL-1α autoantibodies that appeared in patients corresponded to that of IgG. The half life of exogeneous autoantibodies was investigated following administration of autoantibody rich plasma obtained from healthy blood donors to 6 control patients (CP) and 6 progressive IPF patients. These autoantibody levels in their serum were less than 5 ng/ml before administration. Serum was obtained at the indicated time after administration of IL-1α autoantibodies and the level of these autoantibodies in serum was measured, then the half life was calculated. Half life of exogeneous IL-1α autoantibodies in progressive IPF patients was significantly shorter than that in CP (71.3±31.8 hr vs 352.0±98.3 hr, p<0.01).These findings suggested that IL-1α autoantibodies were generated in response to the inflammatory process of rapidly progressive IPF and may act as a regulatory factor for IL-1α

Risk factors for incisional hernia according to different wound sites after open hepatectomy using combinations of vertical and horizontal incisions: A multicenter cohort study.

Background:Although several risk factors for incisional hernia after hepatectomy have been reported, their relationship to different wound sites has not been investigated. Therefore, this study aimed to examine the risk factors for incisional hernia according to various wound sites after hepatectomy.Methods:Patients from the Osaka Liver Surgery Study Group who underwent open hepatectomy using combinations of vertical and horizontal incisions (J-shaped incision, reversed L-shaped incision, reversed T-shaped incision, Mercedes incision) between January 2012 and December 2015 were included. Incisional hernia was defined as a hernia occurring within 3 y after surgery. Abdominal incisional hernia was classified into midline incisional hernia and transverse incisional hernia. The risk factors for each posthepatectomy incisional hernia type were identified.Results:A total of 1057 patients met the inclusion criteria. The overall posthepatectomy incisional hernia incidence rate was 5.9% (62 patients). In the multivariate analysis, the presence of diabetes mellitus and albumin levels <3.5 g/dL were identified as independent risk factors. Moreover, incidence rates of midline and transverse incisional hernias were 2.4% (25 patients), and 2.3% (24 patients), respectively. In multivariate analysis, the independent risk factor for transverse incisional hernia was the occurrence of superficial or deep incisional surgical site infection, and interrupted suturing for midline incisional hernia.Conclusions:Risk factors for incisional hernia after hepatectomy depend on the wound site. To prevent incisional hernia, running suture use might be better for midline wound closure. The prevention of postoperative wound infection is important for transverse wounds, under the presumption of preoperative nutrition and normoglycemia

A High C-Reactive Protein Level on Postoperative Day 7 is Associated with Poor Survival of Patients with Pancreatic Ductal Adenocarcinoma after Resection.

Introduction:Pancreatic ductal adenocarcinoma (PDAC) is a common malignancy. While inflammation-related biomarkers influence patient survival after resection, it has not been known whether postoperative inflammations affect the survival of PDAC patients or not.Methods:It was investigated whether the universal biomarkers on postoperative day (POD) 7 affect the survival of PDAC patients in the retrospective view, and univariate and multivariate analyses were performed via the Cox regression method.Results:Overall, 108 consecutive patients underwent resection; 98 (90.7%) had T3 disease and 73 (67.6%) had lymph node metastases. Thirty-four patients (31.5%) experienced postoperative complications. Compared with preoperative values, the white blood cell count and C-reactive protein (CRP) level on POD 7 were significantly elevated (P < .001 for both); conversely, the lymphocyte count was significantly reduced (P < .001). Among 108 patients, 72 received adjuvant chemotherapy. The median overall survival was 21.0 months; the 5-year survival rate was 22.3%. On multivariate analysis, receiving adjuvant chemotherapy and low CRP levels on POD 7 (<7.6 mg/dL) were prognosticators of better survival. However, the CD classification was not a prognosticator of survival after resection.Conclusions:Adjuvant chemotherapy and postoperative low CRP levels on POD 7 were prognosticators of better survival of PDAC patients after resection. Surgeons should be aware of managing postoperative infections because a high postoperative CRP level is related with unfavorable survival

Comparison of self‐expandable metallic stent placement followed by laparoscopic resection and elective laparoscopic surgery without stent placement for left‐sided colon cancer.

Aim:Self‐expandable metallic stent (SEMS) placement for obstructive colon cancer is widely performed as a bridge to surgery (BTS) procedure before resection. This study aimed to investigate the surgical and oncological results of laparoscopic elective surgery with or without SEMS placement to assess the efficacy of SEMS placement as a BTS.Methods:We retrospectively analyzed consecutive patients with stage II, III, and IV left‐sided colon cancer who underwent elective laparoscopic resection between 2013 and 2019. All patients were divided into two groups: with and without SEMS placement.Results:The SEMS group included 24 patients, whereas the non‐SEMS group included 86 patients. The serum hemoglobin and albumin levels were lower (P = .049, P = .03), and the serum leukocyte and C‐reactive protein levels were higher (P < .0001, P = .022) in the SEMS group. The tumor diameter and tumor circumferential rate were higher in the SEMS group (both P < .0001). No significant differences were observed in operation time, blood loss, postoperative complications, or postoperative hospital stay. After 1:1 propensity score matching, 15 patients in the SEMS group were compared with 15 patients in the non‐SEMS group. The 3‐year overall survival rates of the SEMS and non‐SEMS groups were 87.5% and 88.9%, respectively (P = .97). The 3‐year recurrence‐free survival rates of the SEMS and non‐SEMS groups were 58.2% and 81.7%, respectively (P = .233). No significant difference was found in the sites of recurrence.Conclusion:The perioperative and long‐term outcomes of SEMS placement as a BTS before laparoscopic resection could be acceptable compared with other elective laparoscopic operations without SEMS placement

Vimentin Expression in Tumor Microenvironment Predicts Survival in Pancreatic Ductal Adenocarcinoma: Heterogeneity in Fibroblast Population.

BACKGROUND:The tumor microenvironment, including cancer-associated fibroblasts (CAFs), plays various clinical roles in cancer growth. CAFs are a heterogeneous population and express a variety of mesenchymal markers. However, the clinical roles for CAFs expressing different markers in pancreatic ductal adenocarcinoma (PDAC) remain unknown.METHODS:We reviewed 67 resected PDAC patients who had not received preoperative therapy. Each primary tumor was analyzed for vimentin and α-smooth muscle actin (α-SMA) expression by immunohistochemical and dual immunofluorescence staining.RESULTS:There was no correlation between the percentage of cells expressing vimentin and α-SMA in the tumor stroma (Pearson\u27s correlation coefficient: r = 0.171). Higher vimentin expression (p = 0.018) was associated with significantly shorter overall survival in PDAC patients. Using dual immunofluorescence staining, vimentin-positive CAFs were divided into two subpopulations: co-expression of α-SMA, and no co-expression of α-SMA. In PDAC, the level of co-expression had no effect on survival using univariate analysis (median survival time, 33.3 months for low co-expression vs. 18.2 months for high co-expression; log-rank, p = 0.143). However, multivariate analysis clarified that CAFs expressing vimentin alone was an independent predictor of poor survival (p = 0.014; hazard ratio, 2.305; 95% confidence interval, 1.181-4.497).CONCLUSIONS:Vimentin-positive CAFs without co-expression of α-SMA were associated with poor survival in PDAC, and CAFs possessed molecular and functional heterogeneity in this disease

New Hepatic Resection Criteria for Intermediate-Stage Hepatocellular Carcinoma Can Improve Long-Term Survival: A Retrospective, Multicenter Collaborative Study.

Background:Hepatic resection (HR) is not recommended for intermediate-stage hepatocellular carcinoma (HCC) by the Barcelona Clinic Liver Cancer criteria. We examined the prognostic factors of HR for intermediate-stage HCC and developed new HR criteria for intermediate-stage HCC.Methods:A total of 110 patients who underwent HR without any prior treatment for intermediate-stage HCC between January 2007 and December 2012 were enrolled at eight university hospitals. The outcomes and prognostic factors of HR were evaluated to develop new HR criteria.Results:In terms of tumor size and number, the most significant prognostic factors were within the up-to-seven criteria. Furthermore, serum albumin level ≥35 g/L and serum alpha-fetoprotein (AFP) level

The Elevation in Preoperative Procalcitonin Is Associated with a Poor Prognosis for Patients Undergoing Resection for Colorectal Cancer.

Background:Procalcitonin (PCT) is a well-known marker for bacterial infection; however, the clinical significance of PCT in the long-term prognosis after colorectal cancer (CRC) surgery remains unclear.Methods:This is a retrospective review of 277 patients that underwent CRC surgery to investigate the relationship between preoperative PCT, clinicopathological condition, cancer-specific overall survival (OS), and relapse-free survival (RFS).Results:Median follow-up interval was 5.0 years in all patients. Thirty-six patients developed recurrence, and 46 patients died due to recurrences or metastases of CRC. Preoperative PCT levels were highest in Stage IV patients. The cancer-specific OS in patients with Stage IV/PCT ≤0.05 ng/mL was significantly higher than those with Stage IV/PCT >0.05 ng/mL (3 years survival; 42.3 vs. 14.3%, p = 0.0413). On multivariate analysis, gender, TNM classification, and PCT were identified as significant risk factors for cancer-specific OS in patients with Stage I-III CRC. The cancer-specific OS rate of these patients with PCT ≥0.08 ng/mL, compared with PCT <0.08 ng/mL, was significantly decreased (5 years survival; 59.1 vs. 92.7%, p < 0.0001). TNM classification was finally identified as an independent risk factor for cancer-specific RFS in these patients by multivariate analysis.Conclusion:High preoperative PCT values in CRC patients appeared to be associated with poor OS but not RFS following surgical treatments