Pathologic alterations in podocytes lead to failure of an essential component of the glomerular filtration barrier and proteinuria in chronic kidney diseases. Elevated levels of saturated free fatty ...acid (FFA) are harmful to various tissues, implemented in the progression of diabetes and its complications such as proteinuria in diabetic nephropathy. Here, we investigated the molecular mechanism of palmitate cytotoxicity in cultured mouse podocytes. Incubation with palmitate dose-dependently increased cytosolic and mitochondrial reactive oxygen species, depolarized the mitochondrial membrane potential, impaired ATP synthesis and elicited apoptotic cell death. Palmitate not only evoked mitochondrial fragmentation but also caused marked dilation of the endoplasmic reticulum (ER). Consistently, palmitate upregulated ER stress proteins, oligomerized stromal interaction molecule 1 (STIM1) in the subplasmalemmal ER membrane, abolished the cyclopiazonic acid-induced cytosolic Ca(2+) increase due to depletion of luminal ER Ca(2+). Palmitate-induced ER Ca(2+) depletion and cytotoxicity were blocked by a selective inhibitor of the fatty-acid transporter FAT/CD36. Loss of the ER Ca(2+) pool induced by palmitate was reverted by the phospholipase C (PLC) inhibitor edelfosine. Palmitate-dependent activation of PLC was further demonstrated by following cytosolic translocation of the pleckstrin homology domain of PLC in palmitate-treated podocytes. An inhibitor of diacylglycerol (DAG) kinase, which elevates cytosolic DAG, strongly promoted ER Ca(2+) depletion by low-dose palmitate. GF109203X, a PKC inhibitor, partially prevented palmitate-induced ER Ca(2+) loss. Remarkably, the mitochondrial antioxidant mitoTEMPO inhibited palmitate-induced PLC activation, ER Ca(2+) depletion and cytotoxicity. Palmitate elicited cytoskeletal changes in podocytes and increased albumin permeability, which was also blocked by mitoTEMPO. These data suggest that oxidative stress caused by saturated FFA leads to mitochondrial dysfunction and ER Ca(2+) depletion through FAT/CD36 and PLC signaling, possibly contributing to podocyte injury.
Given the mode of transmission of Middle East respiratory syndrome (MERS), healthcare workers (HCWs) in contact with MERS patients are expected to be at risk of MERS infections. We evaluated the ...prevalence of MERS coronavirus (CoV) immunoglobulin (Ig) G in HCWs exposed to MERS patients and calculated the incidence of MERS-affected cases in HCWs. We enrolled HCWs from hospitals where confirmed MERS patients had visited. Serum was collected 4 to 6 weeks after the last contact with a confirmed MERS patient. We performed an enzyme-linked immunosorbent assay (ELISA) to screen for the presence of MERS-CoV IgG and an indirect immunofluorescence test (IIFT) to confirm MERS-CoV IgG. We used a questionnaire to collect information regarding the exposure. We calculated the incidence of MERS-affected cases by dividing the sum of PCR-confirmed and serology-confirmed cases by the number of exposed HCWs in participating hospitals. In total, 1169 HCWs in 31 hospitals had contact with 114 MERS patients, and among the HCWs, 15 were PCR-confirmed MERS cases in study hospitals. Serologic analysis was performed for 737 participants. ELISA was positive in five participants and borderline for seven. IIFT was positive for two (0.3%) of these 12 participants. Among the participants who did not use appropriate personal protective equipment (PPE), seropositivity was 0.7% (2/294) compared to 0% (0/443) in cases with appropriate PPE use. The incidence of MERS infection in HCWs was 1.5% (17/1169). The seroprevalence of MERS-CoV IgG among HCWs was higher among participants who did not use appropriate PPE.
Background
Although transarterial chemoembolization is recommended as the standard treatment for Barcelona Clinic Liver Cancer stage B hepatocellular carcinoma (BCLC‐B HCC), other treatments ...including liver resection have been used. This study aimed to determine the survival benefit of treatment strategies including resection for BCLC‐B HCC compared with non‐surgical treatments.
Methods
The nationwide multicentre database of the Korean Liver Cancer Association was reviewed. Patients with BCLC‐B HCC who underwent liver resection as a first or second treatment within 2 years of diagnosis and patients who received non‐surgical treatment were selected randomly. Survival outcomes of propensity score‐matched groups were compared.
Results
Among 887 randomly selected patients with BCLC‐B HCC, 83 underwent liver resection as first or second treatment and 597 had non‐surgical treatment. After propensity score matching, the two groups were well balanced (80 patients in each group). Overall median survival in the resection group was better than that for patients receiving non‐surgical treatment (50·9 versus 22·1 months respectively; P < 0·001). The 1‐, 2‐, 3‐ and 5‐year overall survival rates in the resection group were 90, 88, 75 and 63 per cent, compared with 79, 48, 35 and 22 per cent in the no‐surgery group (P < 0·001). In multivariable analysis, non‐surgical treatment only (hazard ratio (HR) 3·35, 95 per cent c.i. 2·16 to 5·19; P < 0·001), albumin level below 3·5 g/dl (HR 1·96, 1·22 to 3·15; P = 0·005) and largest tumour size greater than 5·0 cm (HR 1·81, 1·20 to 2·75; P = 0·005) were independent predictors of worse overall survival.
Conclusion
Treatment strategies that include liver resection offer a survival benefit compared with non‐surgical treatments for potentially resectable BCLC‐B HCC.
Selected patients benefit
This study aimed to evaluate endogenous metabolic markers of hepatic cytochrome P450 (CYP)3A activity in healthy subjects using a metabolomics approach. Twenty‐four subjects received the following ...medication during the following three study periods: 1 mg of i.v. midazolam alone (control phase), 1 mg of i.v. midazolam after 4 days of pretreatment with 400 mg of ketoconazole once daily (CYP3A‐inhibited phase), and 2.5 mg of i.v. midazolam after 10 days of pretreatment with 600 mg of rifampicin once daily (CYP3A‐induced phase). During each study period, 24 h before and after the administration of midazolam, urine samples were collected at 12‐h intervals for metabolomic analyses. We derived an equation to predict midazolam clearance (CL) based on several of these markers. We demonstrated that a combination of the concentrations and ratios of several endogenous metabolites and the CYP3A5*3 genotype is a reliable predictive marker of hepatic CYP3A activity as assessed by i.v. administration of midazolam.
Clinical Pharmacology & Therapeutics (2013); 94 5, 601–609. doi:10.1038/clpt.2013.128
Merons which are topologically equivalent to one-half of skyrmions can exist only in pairs or groups in two-dimensional (2D) ferromagnetic (FM) systems. The recent discovery of meron lattice in ...chiral magnet Co
Zn
Mn
raises the immediate challenging question that whether a single meron pair, which is the most fundamental topological structure in any 2D meron systems, can be created and stabilized in a continuous FM film? Utilizing winding number conservation, we develop a new method to create and stabilize a single pair of merons in a continuous Py film by local vortex imprinting from a Co disk. By observing the created meron pair directly within a magnetic field, we determine its topological structure unambiguously and explore the topological effect in its creation and annihilation processes. Our work opens a pathway towards developing and controlling topological structures in general magnetic systems without the restriction of perpendicular anisotropy and Dzyaloshinskii-Moriya interaction.
Background Current practice of adding concurrent–adjuvant chemotherapy to radiotherapy (CRT) for treating advanced nasopharyngeal carcinoma is based on the Intergroup-0099 Study published in 1998. ...However, the outcome for the radiotherapy-alone (RT) group in that trial was substantially poorer than those in other trials, and there were no data on late toxicities. Verification of the long-term therapeutic index of this regimen is needed. Methods Patients with nonkeratinizing nasopharyngeal carcinoma staged T1-4N2-3M0 were randomly assigned to RT (176 patients) or to CRT (172 patients) using cisplatin (100 mg/m2) every 3 weeks for three cycles in concurrence with radiotherapy, followed by cisplatin (80 mg/m2) plus fluorouracil (1000 mg per m2 per day for 4 days) every 4 weeks for three cycles. Primary endpoints included overall failure-free rate (FFR) (the time to first failure at any site) and progression-free survival. Secondary endpoints included overall survival, locoregional FFR, distant FFR, and acute and late toxicity rates. All statistical tests were two-sided. Results The two treatment groups were well balanced in all patient characteristics, tumor factors, and radiotherapy parameters. Adding chemotherapy statistically significantly improved the 5-year FFR (CRT vs RT: 67% vs 55%; P = .014) and 5-year progression-free survival (CRT vs RT: 62% vs 53%; P = .035). Cumulative incidence of acute toxicity increased with chemotherapy by 30% (CRT vs RT: 83% vs 53%; P < .001), but the 5-year late toxicity rate did not increase statistically significantly (CRT vs RT: 30% vs 24%; P = .30). Deaths because of disease progression were reduced statistically significantly by 14% (CRT vs RT: 38% vs 24%; P = .008), but 5-year overall survival was similar (CRT vs RT: 68% vs 64%; P = .22; hazard ratio of CRT = 0.81, 95% confidence interval = 0.58 to 1.13) because deaths due to toxicity or incidental causes increased by 7% (CRT vs RT: 1.7% vs 0, and 8.1% vs 3.4%, respectively; P = .015). Conclusions Adding concurrent–adjuvant chemotherapy statistically significantly reduced failure and cancer-specific deaths when compared with radiotherapy alone. Although there was no statistically significant increase in major late toxicity, increase in noncancer deaths narrowed the resultant gain in overall survival.
WHO grade II gliomas are divided into three classes:
-wildtype,
-mutant and no 1p/19q codeletion, and
-mutant and 1p/19q-codeleted. Different molecular subtypes have been reported to have prognostic ...differences and different chemosensitivity. Our aim was to evaluate the predictive value of imaging phenotypes assessed with the Visually AcceSAble Rembrandt Images lexicon for molecular classification of lower grade gliomas.
MR imaging scans of 175 patients with lower grade gliomas with known
mutation and 1p/19q-codeletion status were included (78 grade II and 97 grade III) in the discovery set. MR imaging features were reviewed by using Visually AcceSAble Rembrandt Images (VASARI); their associations with molecular markers were assessed. The predictive power of imaging features for
-wild type tumors was evaluated using the Least Absolute Shrinkage and Selection Operator. We tested the model in a validation set (40 subjects).
Various imaging features were significantly different according to
mutation. Nonlobar location, larger proportion of enhancing tumors, multifocal/multicentric distribution, and poor definition of nonenhancing margins were independent predictors of an
wild type according to the Least Absolute Shrinkage and Selection Operator. The areas under the curve for the prediction model were 0.859 and 0.778 in the discovery and validation sets, respectively. The
-mutant, 1p/19q-codeleted group frequently had mixed/restricted diffusion characteristics and showed more pial invasion compared with the
-mutant, no codeletion group.
Preoperative MR imaging phenotypes are different according to the molecular markers of lower grade gliomas, and they may be helpful in predicting the
mutation status.
Gliomas are associated with high mortality because of their exceedingly invasive character. As these tumors acquire their invasiveness from low-grade tumors, it is very important to understand the ...detailed molecular mechanisms of invasion onset. Recent evidences suggest the significant role of microRNAs in tumor invasion. Thus, we hypothesized that deregulation of microRNAs may be important for the malignant progression of gliomas. We found that the aberrant expression of miR-21 is responsible for glioma invasion by disrupting the negative feedback circuit of Ras/MAPK signaling, which is mediated by Spry2. Upregulation of miR-21 was triggered by tumor microenvironmental factors such as hyaluronan and growth factors in glioma cells lacking functional phosphatase and tensin homolog (PTEN), but not harboring wild-type PTEN. Consistently with these in vitro results, Spry2 protein levels were significantly decreased in 79.7% of invasive WHO grade II-IV human glioma tissues, but not in non-invasive grade I and normal tissues. The Spry2 protein levels were not correlated with their mRNA levels, but inversely correlated with miR-21 levels. Taken together, these results suggest that the post-transcriptional regulation of Spry2 by miR-21 has an essential role on the malignant progression of human gliomas. Thus, Spry2 may be a novel therapeutic target for treating gliomas.
A novel type of spherical and porous composites were synthesized to dually benefit from reduced graphene oxide (rGO) and magnetic materials as supports for enzyme immobilization. Three magnetic ...composite particles of Fe3O4 and rGO containing 71% (rGO-Fe3O4-M1), 36% (rGO-Fe3O4-M2), and 18% (rGO-Fe3O4-M3) Fe were prepared using a one-pot spray pyrolysis method and were used for the immobilization of the model enzymes, laccase and horseradish peroxidase (HRP). The rGO-Fe3O4 composite particles prepared by spray pyrolysis process had a regular shape, finite size, and uniform composition. The immobilization of laccase and HRP on rGO-Fe3O4-M1 resulted in 112 and 89.8% immobilization efficiency higher than that of synthesized pure Fe3O4 and rGO particles, respectively. The stability of laccase was improved by approximately 15-fold at 25 °C. Furthermore, rGO-Fe3O4-M1-immobilized laccase exhibited 92.6% of residual activity after 10 cycles of reuse and was 192% more efficient in oxidizing different phenolic compounds than the free enzyme. Therefore, these unique composite particles containing rGO and Fe3O4 may be promising supports for the efficient immobilization of industrially important enzymes with lower acute toxicity toward Vibrio fischeri than commercial pure Fe3O4 particles.
Abstract Introduction Preeclampsia (PE) is a leading cause of maternal and neonatal mortality and morbidity worldwide. However, the pathophysiology of this disease is not yet fully understood. MiRNA ...plays an important role in post-transcriptional gene regulation. Recent studies have suggested that dysregulation of miRNAs in placental tissue is involved in the pathogenesis of PE. Therefore, we investigated miRNA profiles in PE placenta to understand the miRNA function in PE pathogenesis. Methods MiRNA profiling was performed in 20 formalin-fixed and paraffin-embedded samples (10 placentas from severe PE and 10 from a control group). We used a hybridization-based microarray with a PNA-probe comprised of 158 miRNAs. Results Thirteen miRNAs (miR-92b, miR-197, miR-342-3p, miR-296-5p, miR-26b, miR-25, miR-296-3p, miR-26a, miR-198, miR-202, miR-191, miR-95, and miR-204) were significantly overexpressed and two miRNAs (miR-21 and miR-223) were underexpressed in PE compared with the control group. Among 15 differentially expressed miRNAs, miR-26b, miR-296-5p, and miR-223 were found to be consistent with results from previous studies. We identified 893 genes that were predicted by at least three of four computational algorithms. Target genes participated in several signaling pathways, adherens junction, focal adhesion, and regulation of the actin cytoskeleton. Conclusions Several miRNAs are found to be dysregulated in placentas of PE patients and they seem to be closely associated with the early pathogenesis of PE. Further study is necessary to develop tools for early detection and management.