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Effective heat dissipation is the bottleneck problem for the development and commercialization of GaN-based high-power electronic and photonic devices. To address this challenge and explore the underlying mechanism of phonon transportation across the GaN/AlN heterointerface, in this work, we formed three types of GaN/AlN heterostructures with distinctively different interfacial morphologies by annealing recrystallization approach. It is found that the interfacial thermal conductance (ITC) of GaN/AlN heterostructures can be remarkably improved by tailoring the interfacial crystal structure and phase morphology. Besides the commonly amorphous phase and ideal ordered wurtzite phase, we further found that AlN may present an additional stable rock salt phase at the interfacial region, and its significant effect on interfacial thermal transport has been observed. Using molecular dynamics simulation, we systematically investigated the effects of different GaN/AlN heterojunctions on the ITCs. Our results suggest that heat dissipation at the GaN/AlN interface is dominated by phonons scattered diffusely by the amorphous region at interfaces and the ITC can be significantly enhanced by recrystallizing the amorphous AlN to rock salt one. Furthermore, through phonon vibrational spectrum, we revealed that phonon modes dominate the energy transport across the interfaces of wurtzite AlN/GaN, amorphous AlN/GaN, and rock salt AlN/GaN are significantly different. Finally, we found the ITC increased with the temperature due to the enhanced inelastic phonon scattering and the presence of additional excited phonon modes at higher temperatures. The findings elucidated here provide a clearer insight into the effect of interfacial microstructures on the interfacial thermal resistance of GaN–substrate interface, which also provide a viable heat management strategy for the high-power GaN-based devices. [ABSTRACT FROM AUTHOR]

Fe3O4 nanoparticles were first modified with tetraethoxylsilane to form Fe3O4/SiO2 nanoparticles, followed by the addition of 3-aminopropyltriethoxysilane and 3-thiolpropyltriethoxysilane to introduce -NH2 and -SH groups to the surface of Fe3O4/SiO2 nanoparticles. Gold nanoparticles were further assembled on the surface of Fe3O4/SiO2 via the electrostatic adsorption of -NH2 and the Au-S bond to produce stable core-shell Fe3O4/SiO2/Au gold/magnetic nanoparticles. These Fe3O4/SiO2/Au gold/magnetic nanoparticles were characterized by a variety of techniques such as transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDX), and afterwards conjugated with tetrodotoxin antibodies (Ab) and used as a Raman active substrate (Fe3O4/SiO2/Au-Ab) with Rhodamine B (RhB)-labeled tetrodotoxin antibody as a Raman reporter (Ab-RhB). Upon mixing these reagents with tetrodotoxin (TTX), a sandwich complex [Fe3O4/SiO2/Au-Ab···TTX···Ab-RhB] was generated due to the specific antibody-antigen interactions. The immunocomplex was subsequently separated by an externally applied magnetic source and concentrated into a pellet point, where the laser interrogation of the pellet produced a strong signal characteristic of RhB. The logarithmic intensity of the signal was found to be proportional to the concentration of TTX with a limit of detection of 0.01 μg/mL and a detection linearity range of ~ 0.01-0.5 μg/mL. The established method eliminates the complicated procedures of traditional centrifuging, column separation, and incubation and achieves a rapid detection of tetrodotoxin with improved detection sensitivity. [ABSTRACT FROM AUTHOR]

Motivation New developments in high-throughput genomic technologies have enabled the measurement of diverse types of omics biomarkers in a cost-efficient and clinically-feasible manner. Developing computational methods and tools for analysis and translation of such genomic data into clinically-relevant information is an ongoing and active area of investigation. For example, several studies have utilized an unsupervised learning framework to cluster patients by integrating omics data. Despite such recent advances, predicting cancer prognosis using integrated omics biomarkers remains a challenge. There is also a shortage of computational tools for predicting cancer prognosis by using supervised learning methods. The current standard approach is to fit a Cox regression model by concatenating the different types of omics data in a linear manner, while penalty could be added for feature selection. A more powerful approach, however, would be to incorporate data by considering relationships among omics datatypes. Methods Here we developed two methods: a SKI-Cox method and a wLASSO-Cox method to incorporate the association among different types of omics data. Both methods fit the Cox proportional hazards model and predict a risk score based on mRNA expression profiles. SKI-Cox borrows the information generated by these additional types of omics data to guide variable selection, while wLASSO-Cox incorporates this information as a penalty factor during model fitting. Results We show that SKI-Cox and wLASSO-Cox models select more true variables than a LASSO-Cox model in simulation studies. We assess the performance of SKI-Cox and wLASSO-Cox using TCGA glioblastoma multiforme and lung adenocarcinoma data. In each case, mRNA expression, methylation, and copy number variation data are integrated to predict the overall survival time of cancer patients. Our methods achieve better performance in predicting patients’ survival in glioblastoma and lung adenocarcinoma. [ABSTRACT FROM AUTHOR]

Designing highly active nanozymes for bioanalysis and environmental sensing remains a challenge. In this study, transition metal, palladium (Pd) and iron (Fe), doped germanium oxide (GeO 2) nanozyme was designed and optimized. Compared with the pristine GeO 2 nanozyme, the transition metal doped GeO 2 nanozyme have lower Michaelis-Menten constants and higher catalytic activity, indicating that the Pd and Fe doped GeO 2 nanozyme not only enhance their affinity for the substrate but also improve its catalytic activity. In addition, a colorimetric sensor based on the GeO 2 @Pd–H 2 O 2 -TMB system was constructed for the visual detection of simazine in water samples due to the good affinity between TMB and simazine. This sensor has good selectivity and sensitivity with a detection limit of 6.21 μM because of the highest catalytic performance of GeO 2 @Pd nanozyme. This study broadens the application of nanozymes in environmental field and other nanozymes can also be enhanced in activity by simple transition metal doping. [Display omitted] • A transition metal doped germanium oxide nanozyme was designed and synthesized. • This nanozymes have lower Michaelis-Menten constants and higher enzyme-like activity. • The improved catalytic activity was due to the enhance affinity for the substrate. • A colorimetric sensor was constructed for detection of simazine in water samples. [ABSTRACT FROM AUTHOR]

Multiple myeloma (MM) is a cancer of antibody-making plasma cells. It frequently harbors alterations in DNA and chromosome copy numbers, and can be divided into two major subtypes, hyperdiploid (HMM) and non-hyperdiploid multiple myeloma (NHMM). The two subtypes have different survival prognosis, possibly due to different but converging paths to oncogenesis. Existing methods for identifying the two subtypes are fluorescence in situ hybridization (FISH) and copy number microarrays, with increased cost and sample requirements. We hypothesize that chromosome alterations have their imprint in gene expression through dosage effect. Using five MM expression datasets that have HMM status measured by FISH and copy number microarrays, we have developed and validated a K-nearest-neighbor method to classify MM into HMM and NHMM based on gene expression profiles. Classification accuracy for test datasets ranges from 0.83 to 0.88. This classification will enable researchers to study differences and commonalities of the two MM subtypes in disease biology and prognosis using expression datasets without need for additional subtype measurements. Our study also supports the advantages of using cancer specific characteristics in feature design and pooling multiple rounds of classification results to improve accuracy. We provide R source code and processed datasets at www.ChengLiLab.org/software. [ABSTRACT FROM AUTHOR]

Abstract: The sphingolipid metabolic pathway represents a potential source of new therapeutic targets for numerous hyperproliferative/inflammatory diseases. Targets such as the sphingosine kinases (SphKs) have been extensively studied and numerous strategies have been employed to develop inhibitors against these enzymes. Herein, we report on the optimization of our novel small-molecule inhibitor SKI-I (N′-[(2-hydroxy-1-naphthyl)methylene]-3-(2-naphthyl)-1H-pyrazole-5-carbohydrazide) and the identification of a SphK1-specific analog, SKI-178, that is active in vitro and in vivo. This SphK1 specific small-molecule, non-lipid like, inhibitor will be of use to elucidate the roles of SphK1 and SphK2 in the development/progression of hyperproliferative and/or inflammatory diseases. [ABSTRACT FROM AUTHOR]

Abstract: Currently, there are conflicting data in literature regarding contribution of bone marrow stromal cells (BMSCs) to bone formation when the cells are systemically delivered in recipient animals. To understand if BMSCs contribute to bone cell phenotype and bone formation in osteogenesis imperfecta bones (OI), MSCs marked with GFP were directly infused into the femurs of a mouse model of OI (oim). The contribution of the cells to the cell phenotype and bone formation was assessed by histology, immunohistochemistry and biomechanical loading of recipient bones. Two weeks following infusion of BMSCs, histological examination of the recipient femurs demonstrated presence of new bone when compared to femurs injected with saline which showed little or no bone formation. The new bone contained few donor cells as demonstrated by GFP fluorescence. At 6weeks following cell injection, new bone was still detectable in the recipient femurs but was enhanced by injection of the cells suspended in pepsin solublized type I collagen. Immunofluorescence and immunohistochemical staining showed that donor GFP positive cells in the new bone were localized with osteocalcin expressing cells suggesting that the cells differentiated into osteoblasts in vivo. Biomechanical loading to failure in thee point bending, revealed that, femurs infused with BMSCs in PBS or in soluble type I collagen were biomechanically stronger than those injected with PBS or type I collagen alone. Taken together, the results indicate that transplanted cells differentiated into osteoblasts in vivo and contributed to bone formation in vivo; we also speculate that donor cells induced differentiation or recruitment of endogenous cells to initiate reparative process at early stages following transplantation. [ABSTRACT FROM AUTHOR]

To study the mechanical properties of rocks with cracks of different angles around the hole, the particle flow discrete element software PFC2D and laboratory experiments were used to conduct uniaxial compression tests on rocks with cracks of different angles around the hole. The failure behaviour and mechanical properties of rock samples with cracks of different angles were analysed, the failure modes of rocks with defects of different angles were revealed, and the crack propagation and stress evolution of rocks with cracks of different angles were studied. The results show that compared with the intact rocks, the peak stress, elastic modulus, peak strain, initiation stress, damage stress, and other properties of fissure rocks with different angles around the hole are lower; the defect combination of different fissure angles around the hole has a substantial impact on the failure characteristics of rock samples—different fissure angles in rock samples produce different failure modes, resulting in different crack development and propagation processes. Through the comparative study of indoor experiments, the results of indoor real rock and numerical simulation experiments are verified, and the macroscopic failure characteristics of rocks are similar. This study can correctly understand the mechanical properties of fissure rocks with different angles around the hole and provide theoretical guidance for practical rock engineering. [ABSTRACT FROM AUTHOR]

Background: The functional contribution of non-myocyte cardiac cells, such as inflammatory cells, in the setup of heart failure in response to doxorubicin (Dox) is recently becoming of growing interest. Objectives: The study aims to evaluate the role of macrophages in cardiac damage elicited by Dox treatment. Methods: C57BL/6 mice were treated with one intraperitoneal injection of Dox (20 mg/kg) and followed up for 5 days by cardiac ultrasounds (CUS), histological, and flow cytometry evaluations. We also tested the impact of Dox in macrophage-depleted mice. Rat cardiomyoblasts were directly treated with Dox (D-Dox) or with a conditioned medium from cultured murine macrophages treated with Dox (M-Dox). Results: In response to Dox, macrophage infiltration preceded cardiac damage. Macrophage depletion prevents Dox-induced damage, suggesting a key role of these cells in promoting cardiotoxicity. To evaluate the crosstalk between macrophages and cardiac cells in response to DOX, we compared the effects of D-Dox and M-Dox in vitro. Cell vitality was lower in cardiomyoblasts and apoptosis was higher in response to M-Dox compared with D-Dox. These events were linked to p53-induced mitochondria morphology, function, and autophagy alterations. We identify a mechanistic role of catecholamines released by Dox-activated macrophages that lead to mitochondrial apoptosis of cardiac cells through β-AR stimulation. Conclusions: Our data indicate that crosstalk between macrophages and cardiac cells participates in cardiac damage in response to Dox. [ABSTRACT FROM AUTHOR]

Reverse transcription quantitative polymerase chain reaction (RT-qPCR) is an accurate method for quantifying gene expression levels. Choosing appropriate reference genes to normalize the data is essential for reducing errors. Gelsemium elegans is a highly poisonous but important medicinal plant used for analgesic and anti-swelling purposes. Gelsenicine is one of the vital active ingredients, and its biosynthesis pathway remains to be determined. In this study, G. elegans leaf tissue with and without the application of one of four hormones (SA, MeJA, ETH, and ABA) known to affect gelsenicine synthesis, was analyzed using ten candidate reference genes. The gene stability was evaluated using GeNorm, NormFinder, BestKeeper, ∆CT, and RefFinder. The results showed that the optimal stable reference genes varied among the different treatments and that at least two reference genes were required for accurate quantification. The expression patterns of 15 genes related to the gelsenicine upstream biosynthesis pathway was determined by RT-qPCR using the relevant reference genes identified. Three genes 8-HGO, LAMT, and STR, were found to have a strong correlation with the amount of gelsenicine measured in the different samples. This research is the first study to examine the reference genes of G. elegans under different hormone treatments and will be useful for future molecular analyses of this medically important plant species. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Ischemia with nonobstructive coronary arteries (INOCA) is a prevailing finding in patients with angina. However, the main factors underlying the risk of being rehospitalized for chest pain in patients with INOCA remain mostly unknown. RESEARCH DESIGN AND METHODS: We evaluated INOCA patients referred to the "Casa di Cura Montevergine" in Mercogliano (Avellino), Italy, from January 2016 to January 2021 for percutaneous coronary intervention (PCI). In these subjects, we assessed the impact of the stress hyperglycemia ratio (SHR), defined as the ratio of mmol/L blood glucose and % HbA1c, on the risk of rehospitalization for chest pain. RESULTS: A total of 2,874 patients with INOCA successfully completed the study. At the 1-year follow-up, the risk of rehospitalization for chest pain was significantly higher (P < 0.001) in INOCA patients with SHR >1 compared to patients with SHR ≤1. These findings were confirmed by multivariable analyses (adjusting for potential confounders, including age, BMI, blood pressure, heart rate, chronic kidney disease, and cholesterol), propensity score matching, and inverse probability of treatment weighting. CONCLUSIONS: Our data indicate, to our knowledge for the first time, that SHR on hospital admission significantly and independently increases the risk of rehospitalization for chest pain in INOCA patients. [ABSTRACT FROM AUTHOR]

Small cell lung cancer (SCLC) is a deadly neuroendocrine malignancy with high metastasis. However, the heterogeneity of metastatic SCLC at the single‐cell level remains elusive. The single‐cell transcriptome of a total of 24 081 cells in metastatic lymph node samples from seven SCLC patients via endobronchial ultrasound‐guided transbronchial needle aspiration (EBUS‐TBNA) is examined. Genomic alterations are also examined by whole exome sequencing (WES) and the immune infiltration between SCLC and non‐SCLC (NSCLC) is compared using public single‐cell RNA sequencing (scRNA‐seq) data. It is identified that malignant cells in lymph‐node metastatic SCLC have inter‐patient and intra‐tumor heterogeneity characterized by distinct ASCL1 and NEUROD1 expression patterns. High expression of genes such as FZD8 in WNT pathway is associated with drug resistance in malignant cells. Compared to NSCLC, SCLC harbors a unique immunosuppressive tumor microenvironment. Malignant cells exhibit a pattern of attenuated MHC‐I antigen presentation‐related gene expression, which is associated with relatively low proportion of exhausted T cells. Natural killer (NK) cells display impaired antitumor function with high expression of TGFBR2. This work characterizes the inter‐patient and intra‐tumor heterogeneity of metastatic SCLC and uncovers the exhaustion signatures in NK cells, which may pave the way for novel treatments for SCLC including immune checkpoint blockade‐based immunotherapy. [ABSTRACT FROM AUTHOR]

Background & Objective: Genome-wide profiles of tumors obtained using functional genomics platforms are being deposited to the public repositories at an astronomical scale, as a result of focused efforts by individual laboratories and large projects such as the Cancer Genome Atlas (TCGA) and the International Cancer Genome Consortium. Consequently, there is an urgent need for reliable tools that integrate and interpret these data in light of current knowledge and disseminate results to biomedical researchers in a user-friendly manner. We have built the canEvolve web portal to meet this need. Results: canEvolve query functionalities are designed to fulfill most frequent analysis needs of cancer researchers with a view to generate novel hypotheses. canEvolve stores gene, microRNA (miRNA) and protein expression profiles, copy number alterations for multiple cancer types, and protein-protein interaction information. canEvolve allows querying of results of primary analysis, integrative analysis and network analysis of oncogenomics data. The querying for primary analysis includes differential gene and miRNA expression as well as changes in gene copy number measured with SNP microarrays. canEvolve provides results of integrative analysis of gene expression profiles with copy number alterations and with miRNA profiles as well as generalized integrative analysis using gene set enrichment analysis. The network analysis capability includes storage and visualization of gene co-expression, inferred gene regulatory networks and protein-protein interaction information. Finally, canEvolve provides correlations between gene expression and clinical outcomes in terms of univariate survival analysis. Conclusion: At present canEvolve provides different types of information extracted from 90 cancer genomics studies comprising of more than 10,000 patients. The presence of multiple data types, novel integrative analysis for identifying regulators of oncogenesis, network analysis and ability to query gene lists/pathways are distinctive features of canEvolve. canEvolve will facilitate integrative and meta-analysis of oncogenomics datasets. Availability: The canEvolve web portal is available at http://www.canevolve.org/. [ABSTRACT FROM AUTHOR]

Patients with heart failure (HF) have augmented vascular tone, which increases cardiac workload, impairing ventricular output and promoting further myocardial dysfunction. The molecular mechanisms underlying the maladaptive vascular responses observed in HF are not fully understood. Vascular smooth muscle cells (VSMCs) control vasoconstriction via a Ca2+-dependent process, in which the type 1 inositol 1,4,5-trisphosphate receptor (IP3R1) on the sarcoplasmic reticulum (SR) plays a major role. To dissect the mechanistic contribution of intracellular Ca2+ release to the increased vascular tone observed in HF, we analyzed the remodeling of IP3R1 in aortic tissues from patients with HF and from controls. VSMC IP3R1 channels from patients with HF and HF mice were hyperphosphorylated by both serine and tyrosine kinases. VSMCs isolated from IP3R1VSMC-/- mice exhibited blunted Ca2+ responses to angiotensin II (ATII) and norepinephrine compared with control VSMCs. IP3R1VSMC-/- mice displayed significantly reduced responses to ATII, both in vivo and ex vivo. HF IP3R1VSMC-/- mice developed significantly less afterload compared with HF IP3R1fl/fl mice and exhibited significantly attenuated progression toward decompensated HF and reduced interstitial fibrosis. Ca2+-dependent phosphorylation of the MLC by MLCK activated VSMC contraction. MLC phosphorylation was markedly increased in VSMCs from patients with HF and HF mice but reduced in VSMCs from HF IP3R1VSMC-/- mice and HF WT mice treated with ML-7. Taken together, our data indicate that VSMC IP3R1 is a major effector of increased vascular tone, which contributes to increased cardiac afterload and decompensation in HF. [ABSTRACT FROM AUTHOR]

Zebrafish have become a widely used model organism in developmental biology research. In order to initiate an experimental foundation for aging studies, we have determined some basic gerontological parameters for populations of outbred zebrafish, and the golden sparse strain. Outbred zebrafish manifested a mean life span of about 42 months, with the longest living individual surviving for 66 months. The golden sparse populations had a mean life span of 36 months and a maximum longevity of 58 months. Skeletal length at death increased with age, suggestive of indeterminate growth. A common age-related phenotype was spinal curvature. Radiographic analysis excluded bony changes as the cause of the spinal curvature, suggesting muscle abnormalities as a primary mechanism. These data and a growing abundance of related biological resources suggest that the zebrafish may be a compelling model organism for studies on aging. [Copyright &y& Elsevier]

Recycling hazardous gas of H 2 S is one of the most important strategies to promote sustainable development. Herein, a novel method regarding purifying H 2 S is proposed by using yellow phosphorus and phosphate rock slurry as absorbent. The H 2 SO 4 , formed in situ by H 2 S conversion, can be devoted to decompose phosphate rock, and the spent absorption slurry was applied as raw material for the production of phosphorus chemical products. According to the characterization analysis, it was found that H 2 S was first oxidized to SO 2 via O 2 as well as O 3 induced by P 4. Subsequently, the generated SO 2 dissolved rapidly in water to form H 2 SO 4 , and then reacted with the main component of phosphate rock, CaMg(CO 3) 2. Most notably, the active substances, such as, O 3 , SO 4 •- and OH•, produced in the reaction process, can oxidize H 2 S and HS- to these sulfur products. In addition, trace amounts of Fe3+ and Mn2+ that were dissolved from phosphate rock displayed a promotional effect on the formation of active substances. Consequently, as high as 85% of H 2 S removal efficiency can be obtained even under acidic condition and low temperature. The proposed H 2 S purification method offers a promising option for sulfur recovery and H 2 S pollution control. [Display omitted] • Novel H 2 S removal process using P 4 and phosphate rock slurry system is developed. • The H 2 S is efficiently removed under acidic conditions and low temperature. • The O 3 , OH• and SO 4 •- are the key active species for the H 2 S elimination. • The Mn2+ and Fe3+ ions exhibit significant promoting function on the H 2 S absorption. [ABSTRACT FROM AUTHOR]

RNAs localizing to the outer cell surface have been recently identified in mammalian cells, including RNAs with glycan modifications known as glycoRNAs. However, the functional significance of cell surface RNAs and their production are poorly known. We report that cell surface RNAs are critical for neutrophil recruitment and that the mammalian homologs of the sid-1 RNA transporter are required for glycoRNA expression. Cell surface RNAs can be readily detected in murine neutrophils, the elimination of which substantially impairs neutrophil recruitment to inflammatory sites in vivo and reduces neutrophils' adhesion to and migration through endothelial cells. Neutrophil glycoRNAs are predominantly on cell surface, important for neutrophil-endothelial interactions, and can be recognized by P-selectin (Selp). Knockdown of the murine Sidt genes abolishes neutrophil glycoRNAs and functionally mimics the loss of cell surface RNAs. Our data demonstrate the biological importance of cell surface glycoRNAs and highlight a noncanonical dimension of RNA-mediated cellular functions. [Display omitted] • GlycoRNAs are present in neutrophils and primarily locate on the cell surface • Cell surface RNAs facilitate neutrophil recruitment to inflammatory sites in vivo • Neutrophil glycoRNAs bind to P-selectin on endothelial cells • Sidt genes are required for glycoRNA expression and cell surface RNA function RNAs present on the outer cell surface have been recently identified in mammalian cells, but the functional significance of these cell surface RNAs hasn't been clear. This study reveals roles of cell surface RNAs in mediating neutrophil recruitment to inflammatory sites in mice and the mechanisms regulating cell surface glycoRNA functions and levels. [ABSTRACT FROM AUTHOR]

Abstract: Sphingosine kinase (SphK) is a lipid kinase with oncogenic activity, and SphK inhibitors (SKIs) are known for their anti-cancer activity. Here, we report highly efficient syntheses of SKIs and their aspirinyl (Asp) analogs. Both SKIs and their Asp analogs were highly cytotoxic towards multiple human cancer cell lines; in several cases the Asp analogs were up to three times more effective. Furthermore, they were equally potent inhibitors of SphK. The pharmacokinetic study indicated that SKI-I-Asp cleaved efficiently to form SKI-I and the half-life of SKI-I was increased from ∼7 h in SKI-I to ∼10 h in SKI-I-Asp injected mice, thereby prolonging its effect. In summary, the Asp-conjugated SKIs seem to be promising prodrugs of SKIs where delivery in vivo remains a problem. [ABSTRACT FROM AUTHOR]

Abstract: Sphingosine kinase 1 (SphK1) responds to a variety of growth factor signals by increasing catalytic activity as it translocates to the plasma membrane (PM). Several studies have identified amino acids residues involved in translocation yet how SphK1 increases its catalytic activity remains to be elucidated. Herein, we report that deletion of 21 amino acids from the COOH-terminus of SphK1 (1-363) results in increased catalytic activity relative to wild-type SphK1 (1-384) which is independent of the phosphorylation state of Serine 225 and PMA stimulation. Importantly, HEK293 cells stably expressing the 1-363 protein exhibit enhanced cell growth under serum-deprived cell culture conditions. Together the evidence indicates that the COOH-terminal region of SphK1 encompasses a structural element that is necessary for the increase in catalytic activity in response to PMA treatment and that its deletion renders SphK1 constitutively active with respect to PMA treatment. [Copyright &y& Elsevier]

Abstract: Several studies have demonstrated that sphingosine kinase 1 (SphK1) translocates to the plasma membrane (PM) upon its activation and further suggested the plasma membrane lipid raft microdomain (PMLRM) as a target for SphK1 relocalization. To date, however, direct evidence of SphK1 localization to the PMLRM has been lacking. In this report, using multiple biochemical and subcellular fractionation techniques we demonstrate that endogenous SphK1 protein and its substrate, d-erythro-sphingosine, are present within the PMLRM. Additionally, we demonstrate that the PMA stimulation of SphK1 localized to the PMLRM results in production of sphingosine-1-phosphate as well as induction of cell growth under serum deprivation conditions. We further report that Ser225Ala and Thr54Cys mutations, reported to abrogate phosphatidylserine binding, block SphK1 targeting to the PMLRM and SphK1 induced cell growth. Together these findings provide direct evidence that the PMLRM is the major site of action for SphK1 to overcome serum-deprived cell growth inhibition. [Copyright &y& Elsevier]

Glucagon-like peptide-1 (GLP-1) has been shown to potentiate glucose-stimulated insulin secretion binding GLP-1 receptor on pancreatic β cells. β-arrestin 1 (βARR1) is known to regulate the desensitization of GLP-1 receptor. Mounting evidence indicates that microRNAs (miRNAs, miRs) are fundamental in the regulation of β cell function and insulin release. However, the regulation of GLP-1/βARR1 pathways by miRs has never been explored. Our hypothesis is that specific miRs can modulate the GLP-1/βARR1 axis in β cells. To test this hypothesis, we applied a bioinformatic approach to detect miRs that could target βARR1; we identified hsa-miR-7-5p (miR-7) and we validated the specific interaction of this miR with βARR1. Then, we verified that GLP-1 was indeed able to regulate the transcription of miR-7 and βARR1, and that miR-7 significantly regulated GLP-1-induced insulin release and cyclic AMP (cAMP) production in β cells. Taken together, our findings indicate, for the first time, that miR-7 plays a functional role in the regulation of GLP-1-mediated insulin release by targeting βARR1. These results have a decisive clinical impact given the importance of drugs modulating GLP-1 signaling in the treatment of patients with type 2 diabetes mellitus. [ABSTRACT FROM AUTHOR]

The symptoms most commonly reported by patients affected by coronavirus disease (COVID-19) include cough, fever, and shortness of breath. However, other major events usually observed in COVID-19 patients (e.g., high blood pressure, arterial and venous thromboembolism, kidney disease, neurologic disorders, and diabetes mellitus) indicate that the virus is targeting the endothelium, one of the largest organs in the human body. Herein, we report a systematic and comprehensive evaluation of both clinical and preclinical evidence supporting the hypothesis that the endothelium is a key target organ in COVID-19, providing a mechanistic rationale behind its systemic manifestations. [ABSTRACT FROM AUTHOR]

Liver cancers are highly heterogeneous with poor prognosis and drug response. A better understanding between genetic alterations and drug responses would facilitate precision treatment for liver cancers. To characterize the landscape of pharmacogenomic interactions in liver cancers, we developed a protocol to establish human liver cancer cell models at a success rate of around 50% and generated the Liver Cancer Model Repository (LIMORE) with 81 cell models. LIMORE represented genomic and transcriptomic heterogeneity of primary cancers. Interrogation of the pharmacogenomic landscape of LIMORE discovered unexplored gene-drug associations, including synthetic lethalities to prevalent alterations in liver cancers. Moreover, predictive biomarker candidates were suggested for the selection of sorafenib-responding patients. LIMORE provides a rich resource facilitating drug discovery in liver cancers. • Liver Cancer Model Repository (LIMORE) consists of 81 liver cancer cell models • LIMORE recapitulated genetic heterogeneity of human liver cancers • Molecular and drug screenings provide a pharmacogenomic landscape in liver cancers • Interrogation of the landscape informs biomarkers for liver cancer treatment Qiu et al. establish the Liver Cancer Model Repository, combining public and newly generated cell lines, which represents genomic and transcriptomic heterogeneity of Eastern Asian hepatocellular carcinomas, and use it to reveal gene-drug associations and potential biomarkers for selecting sorafenib-responding patients. [ABSTRACT FROM AUTHOR]

Inflammation and fibrosis in human liver are often precursors to hepatocellular carcinoma (HCC), yet none of them is easily modeled in animals. We previously generated transgenic mice with hepatocyte-specific expressed herpes simplex virus thymidine kinase (HSV-tk). These mice would develop hepatitis with the administration of ganciclovir (GCV). However, our HSV-tk transgenic mice developed hepatitis and HCC tumor as early as six months of age even without GCV administration. We analyzed the transcriptome of the HSV-tk HCC tumor and hepatitis tissue using microarray analysis to investigate the possible causes of HCC. Gene Ontology (GO) enrichment analysis showed that the up-regulated genes in the HCC tissue mainly include the immune-inflammatory and cell cycle genes. The down-regulated genes in HCC tumors are mainly concentrated in the regions related to lipid metabolism. Gene set enrichment analysis (GSEA) showed that immune-inflammatory-related signals in the HSV-tk mice are up-regulated compared to those in Notch mice. Our study suggests that the immune system and inflammation play an important role in HCC development in HSV-tk mice. Specifically, increased expression of immune-inflammatory-related genes is characteristic of HSV-tk mice and that inflammation-induced cell cycle activation maybe a precursory step to cancer. The HSV-tk mouse provides a suitable model for the study of the relationship between immune-inflammation and HCC, and their underlying mechanism for the development of therapeutic application in the future. [ABSTRACT FROM AUTHOR]