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Bone homeostasis is regulated by bone morphogenic proteins (BMPs), among which BMP9 is one of the most osteogenic. Here, we have found that BMP9 rapidly increases the protein expression of hypoxia-inducible factor-1α (HIF-1α) in osteoblasts under normoxic conditions more efficiently than BMP2 or BMP4. A combination of BMP9 and hypoxia further increased HIF-1α protein expression. HIF-1α protein induction by BMP9 is not accompanied by messenger RNA (mRNA) increase and is inhibited by the activation of prolyl hydroxylase domain (PHD)-containing protein, indicating that BMP9 induces HIF-1α protein expression by inhibiting PHD-mediated protein degradation. BMP9-induced HIF-1α protein increase was abrogated by inhibitors of phosphoinositide 3-kinase (PI3K) and protein kinase B (AKT) kinase, indicating that it is mediated by PI3K-AKT signaling pathway. BMP9 increased mRNA expression of pyruvate dehydrogenase kinase 1 (PDK1), a glycolytic enzyme, and vascular endothelial growth factor-A (VEGF-A), an angiogenic factor, in osteoblasts. Notably, BMP9-induced mRNA expression of PDK1, but not that of VEGF-A, was significantly inhibited by small interference RNA-mediated knockdown of Hif-1α. BMP9-induced matrix mineralization and osteogenic marker gene expressions were significantly inhibited by chemical inhibition and gene knockdown of either Hif-1α or Pdk-1, respectively. Since increased glycolysis is an essential feature of differentiated osteoblasts, our findings indicate that HIF-1α expression is important in BMP9-mediated osteoblast differentiation through the induction of PDK1.Angiogenesis and MYC expression associate with poor outcome in diffuse large B-cell lymphoma (DLBCL). MYC promotes neo-vasculature development but whether its deregulation in DLBCL contributes to angiogenesis is unclear. Examination of this relationship may uncover novel pathogenic regulatory circuitry as well as anti-angiogenic strategies in DLBCL. Here, we show that MYC expression positively correlates with vascular endothelial growth factor (VEGF) expression and angiogenesis in primary DLBCL biopsies, independently of dual expressor status or cell-of-origin classification. We found that MYC promotes VEGFA expression, a correlation that was validated in large datasets of mature B-cell tumours. Using DLBCL cell lines and patient-derived xenograft models, we identified the second messenger cyclic-AMP (cAMP) as a potent suppressor of MYC expression, VEGFA secretion and angiogenesis in DLBCL in normoxia. In hypoxia, cAMP switched targets and suppressed hypoxia-inducible factor 1α, a master regulator of VEGFA/angiogenesis in low oxygen environments. Lastly, we used the phosphodiesterase 4b (Pde4b) knockout mouse to demonstrate that the cAMP/PDE4 axis exercises additional anti-angiogenesis by directly targeting the lymphoma microenvironment. In conclusion, MYC could play a direct role in DLBCL angiogenesis, and modulation of cAMP levels, which can be achieved with clinical grade PDE4 inhibitors, has cell and non-cell autonomous anti-angiogenic activity in DLBCL.Anastomotic leak (AL) is a severe complication after esophagectomy. Clinical presentation of AL is diverse and there is large practice variation regarding treatment of AL. This study aimed to explore different AL treatment strategies and their underlying rationale. This mixed-methods study consisted of an international survey among upper gastro-intestinal (GI) surgeons and focus groups with expert upper GI surgeons. The survey included 10 case vignettes and data sources were integrated after separate analysis. The survey was completed by 188 respondents (completion rate 69%) and 6 focus groups were conducted with 20 international experts. Prevention of mortality was the most important goal of primary treatment. Goals of secondary treatment were to promote tissue healing, return to oral feeding and safe hospital discharge. There was substantial variation in the preferred treatment principles (e.g. drainage or defect closure) and modalities (e.g. stent or endoVAC) within different presentations of AL. Patients with local symptoms were treated by supportive means only or by non-surgical drainage and/or defect closure. Drainage was routinely performed in patients with intrathoracic collections and often combined with defect closure. Patients with conduit necrosis were predominantly treated by resection and reconstruction of the anastomosis or by esophageal diversion. This mixed-methods study shows that overall treatment strategies for AL are determined by vitality of the conduit and presence of intrathoracic collections. There is large variation in preferred treatment principles and modalities. Future research may investigate optimal treatment for specific AL presentations and aim to develop consensus-based treatment guidelines for AL after esophagectomy.Small extracellular vesicles (sEVs) are nanometer-sized membranous vesicles that contribute to the pathogenesis of atrial fibrillation (AF). Here, we investigated the role of sEVs derived from patients with persistent AF in the pathophysiology of AF. First, we evaluated the pathological effects of sEVs derived from the peripheral blood of patients with persistent AF (AF-sEVs). AF-sEVs treatment reduced cell viability, caused abnormal Ca2+ handling, induced reactive oxygen species (ROS) production and led to increased CaMKII activation of non-paced and paced atrial cardiomyocytes. Next, we analyzed the miRNA profile of AF-sEVs to investigate which components of AF-sEVs promote arrhythmias, and we selected six miRNAs that correlated with CaMKII activation. qRT-PCR experiment identified that miR-30a-5p was significantly down-regulated in AF-sEVs, paced cardiomyocytes, and atrial tissues of patients with persistent AF. CaMKII was predicted by bioinformatics analysis as a miR-30a-5p target gene and validated by a dual luciferase reporter; hence, we evaluated the effects of miR-30a-5p on paced cardiomyocytes and validated miR-30a-5p as a pro-arrhythmic signature of AF-sEVs. Consequently, AF-sEVs-loaded with miR-30a-5p attenuated pacing-induced Ca2+-handling abnormalities, whereas AF-sEVs-loaded with anti-miR-30a-5p reversed the change in paced cardiomyocytes. Taken together, the regulation of CaMKII by miR-30a-5p revealed that miR-30a-5p is a major mediator for AF-sEVs-mediated AF pathogenesis. Accordingly, these findings suggest that sEVs derived from patients with persistent AF exacerbate arrhythmogenesis via miR-30a-5p.

This phase I/II study was conducted to evaluate the efficacy, safety and pharmacokinetics of streptozocin (STZ) in Japanese patients with unresectable or metastatic gastroenteropancreatic neuroendocrine tumors.

Twenty-two patients received up to 4cycles of intravenous STZ at either 500mg/m2 once daily for 5 consecutive days every 6weeks (daily regimen) or at 1000-1500mg/m2 once weekly for 6weeks (weekly regimen). Tumor response was evaluated using the modified RECIST criteria ver. 1.1, and adverse events were assessed by grade according to the National Cancer Institute CTCAE (ver. 4.0).

Fourteen (63.6%) patients completed the study protocol. No patients had complete response; partial response in 2 (9.1%), stable disease in 17 (77.3%), non-complete response/non-progressive disease in 2 (9.1%) and only 1 (4.5%) had non-evaluable disease. Excluding the latter, the response rate in the daily and weekly regimens was 6.7% (1/15) and 16.7% (1/6), respectively, with an overall response rate of 9.5% (2/21). However, the best overall response in each patient showed that the disease control rate was 100%.Adverse events occurred in all 22 patients, including 17 grade 3 adverse events in 11 patients; however, no grade 4 or 5 adverse events were reported. Prophylactic hydration and antiemetic treatment reduced the severity and incidence of nephrotoxicity, nausea and vomiting. Plasma STZ concentrations decreased rapidly after termination of infusion, with a half-life of 32-40min. Neither repeated administration nor dose increases affected pharmacokinetic parameters.

STZ may be a useful option for Japanese patients with unresectable or metastatic gastroenteropancreatic neuroendocrine tumors.

STZ may be a useful option for Japanese patients with unresectable or metastatic gastroenteropancreatic neuroendocrine tumors.Caenorhabditis elegans contains two pathways for propionate metabolism, the vitamin B12-dependent and shunt pathways, which are similar to those in humans. In this study, we monitored the changes in propionate metabolism in the whole body of C. elegans using novel 13CO2 gas analysis. We measured the increase in 13CO2 excreted in the air after administering [1-13C]-labeled propionate ([13C]propionate) to the worms. The 13CO2 generated from [13C]propionate in C. elegans increased in a dose-dependent manner, reaching a maximum at 48 h. Enhanced expression of propionate metabolism-related genes was observed after administration of propionate. Knockdown of mmcm-1, which encodes the rate-limiting enzyme of the propionate metabolism, using RNAi reduced 13CO2 excretion. Thus, 13CO2 gas analysis could be confirmed 13CO2 excretion associated with changes in the metabolism of [13C]propionate in nematodes. This analysis can contribute to further understanding of the physiological effects of short-chain fatty acids.

Foods containing both prebiotics and probiotics (synbiotics) might enhance calcium bioavailability.

We investigated the acute effect in young adult women on calcium absorption of consuming (185mL) a synbiotic yogurt (SYN) containing inulin (4 g)andLactobacillus rhamnosus GG (>1×107 CFU/mL) compared with a control yogurt (CON).

Adult normal-weight women (25.0±3.5y, n=30) participated in a 3-wk crossover study testing daily consumption of SYN compared with CON. Habitual dietary intake, bone mineral density (BMD), calcium biomarkers, and serum 25-hydroxyvitamin D were measured at baseline. Calcium absorption was tested after each phase of the study using a 42Ca oral tracer. Cumulative tracer recovery was measured in 0-4-h, 0-24-h, and0-36-hurine pools collected postdosing. The SYN/CON tracer ratio from the timed urine pools was the primary outcome. A beneficial response to SYN was defined as 0-36-hSYN/CON tracer ratio>1.

Net 42Ca recovered increased over time in each of the SYN and CON urine pools daily consumption of a synbiotic yogurt enhanced calcium absorption relative to a control yogurt in adult women. Given the observed time delays in tracer recovery, enhancement of calcium absorption likely occurred in the large intestine.The study was registered at clinicaltrials.gov (study registration ID NCT03420716).Clustered competing risks data are commonly encountered in multicenter studies. The analysis of such data is often complicated due to informative cluster size (ICS), a situation where the outcomes under study are associated with the size of the cluster. In addition, the cause of failure is frequently incompletely observed in real-world settings. To the best of our knowledge, there is no methodology for population-averaged analysis with clustered competing risks data with an ICS and missing causes of failure. To address this problem, we consider the semiparametric marginal proportional cause-specific hazards model and propose a maximum partial pseudolikelihood estimator under a missing at random assumption. To make the latter assumption more plausible in practice, we allow for auxiliary variables that may be related to the probability of missingness. The proposed method does not impose assumptions regarding the within-cluster dependence and allows for ICS. The asymptotic properties of the proposed estimators for both regression coefficients and infinite-dimensional parameters, such as the marginal cumulative incidence functions, are rigorously established.

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