Hepatitis C virus infects and perturbs liver stem cells

Hepatitis C virus (HCV) is the leading cause of death from liver disease. How HCV infection causes lasting liver damage and increases cancer risk remains unclear. Here, we identify bipotent liver stem cells as novel targets for HCV infection, and their erroneous differentiation as the potential cause of impaired liver regeneration and cancer development. We show 3D organoids generated from liver stem cells from actively HCV-infected individuals carry replicating virus and maintain low-grade infection over months. Organoids can be infected with a primary HCV isolate. Virus-inclusive single-cell RNA sequencing uncovered transcriptional reprogramming in HCV+ cells supporting hepatocytic differentiation, cancer stem cell development, and viral replication while stem cell proliferation and interferon signaling are disrupted. Our data add a new pathogenesis mechanism-infection of liver stem cells-to the biology of HCV infection that may explain progressive liver damage and enhanced cancer risk through an altered stem cell state.ImportanceThe hepatitis C virus (HCV) causes liver disease, affecting millions. Even though we have effective antivirals that cure HCV, they cannot stop terminal liver disease. We used an adult stem cell-derived liver organoid system to understand how HCV infection leads to the progression of terminal liver disease. Here, we show that HCV maintains low-grade infections in liver organoids for the first time. HCV infection in liver organoids leads to transcriptional reprogramming causing cancer cell development and altered immune response. Our finding shows how HCV infection in liver organoids mimics HCV infection and patient pathogenesis. These results reveal that HCV infection in liver organoids contributes to liver disease progression.

Optimization with photonic wave-based annealers

Many NP-hard combinatorial optimization (CO) problems can be cast as a quadratic unconstrained binary optimization model, which maps naturally to an Ising model. The final spin configuration in the Ising model can adiabatically arrive at a solution to a Hamiltonian, given a known set of interactions between spins. We enhance two photonic Ising machines (PIMs) and compare their performance against classical (Gurobi) and quantum (D-Wave) solvers. The temporal multiplexed coherent Ising machine (TMCIM) uses the bistable response of an electro-optic modulator to mimic the spin up and down states. We compare TMCIM performance on Max-cut problems. A spatial photonic Ising machine (SPIM) convolves the wavefront of a coherent laser beam with the pixel distribution of a spatial light modulator to adiabatically achieve a minimum energy configuration, and solve a number partitioning problem (NPP). Our computational results on Max-cut indicate that classical solvers are still a better choice, while our NPP results show that SPIM is better as the problem size increases. In both cases, connectivity in Ising hardware is crucial for performance. Our results also highlight the importance of better understanding which CO problems are most likely to benefit from which type of PIM. This article is part of the theme issue 'Quantum annealing and computation: challenges and perspectives'.

Efficient big data security analysis on HDFS based on combination of clustering and data perturbation algorithm using health care database

In this manuscript proposes an efficient big data security analysis on HDFS based on the combination of Improved Deep K-means Clustering (IDFKM) algorithm and Modified 3D rotation data perturbation algorithm using health care database. To compile a similar group of data, an Improved Deep K-means Clustering (IDFKM) Algorithm is used as partitioning the medical data. After clustering, Modified 3D rotation data perturbation technique is used to satisfy the privacy requirement of the client. Modified 3D rotation Data Perturbation technique perturbs each and every sensitive data of the cluster and all the key parameters values used for clustering have warehoused in the database file sector. The proposed approach is executed by Java program, its efficiency is assessed by Health care database. The metrics under the study of memory usage attains higher accuracy 34.765%, 23.44%, 52.74%, 18.74%, lower execution time 35.23%, 23.76%, 27.86%, 27.76%, higher Efficiency 26.85%, 38.97%, 28.97%, 35.65%. then the proposed method is compared with the existing methods such asSecurity Analysis of SDN Applications for Big Data with spoofing identity, Tampering with data, Repudiation threats, Information disclosure, Denial of service and Elevation of privileges (STRIDE), Big Data Analysis-based Secure Cluster Management for using Ant Colony Optimization (ACA) Optimized Control Plane in Software-Defined Networks, System Architecture for Secure Authentication and Data Sharing in Cloud Enabled Big Data Environment using LemperlZivMarkow Algorithm (LZMA) and Density-based Clustering of Applications with Noise (DBSCAN), Big Data Based Security Analytics using data based security analytics (BDSA) approach for Protecting Virtualized Infrastructures in Cloud Computing respectively.

Modelling T-cell immunity against hepatitis C virus with liver organoids in a microfluidic coculture system

Hepatitis C virus (HCV) remains a global public health challenge with an estimated 71 million people chronically infected, with surges in new cases and no effective vaccine. New methods are needed to study the human immune response to HCV since in vivo animal models are limited and in vitro cancer cell models often show dysregulated immune and proliferative responses. Here, we developed a CD8+ T cell and adult stem cell liver organoid system using a microfluidic chip to coculture 3D human liver organoids embedded in extracellular matrix with HLA-matched primary human T cells in suspension. We then employed automated phase contrast and immunofluorescence imaging to monitor T cell invasion and morphological changes in the liver organoids. This microfluidic coculture system supports targeted killing of liver organoids when pulsed with a peptide specific for HCV non-structural protein 3 (NS3) (KLVALGINAV) in the presence of patient-derived CD8+ T cells specific for KLVALGINAV. This demonstrates the novel potential of the coculture system to molecularly study adaptive immune responses to HCV in an in vitro setting using primary human cells.

Effectiveness of a home-based cardiovascular disease prevention program during the COVID-19 pandemic

Funding Acknowledgements

Type of funding sources: None.

Background

Home-based cardiovascular disease (CVD) primary prevention (HBPP) and cardiac rehabilitation (HBCR) programs which occupied a small proportion of the overall Preventive Cardiology work in the past have become mainstream during the COVID-19 pandemic.

Purpose

This study aims to analyse the effectiveness of a home-based CVD prevention program implemented during the pandemic in India.

Methods

A retrospective study was conducted on pre-pandemic and pandemic enrolees. Health behaviour, CVD risk factors, physical and mental component score (PCS, MCS) from SF-12 questionnaire, body mass index (BMI), 6-minute walk distance (6MWD), and clinical and biochemical parameters were assessed. A multidisciplinary team consisting of Physician, Physiotherapist, Dietician and Counselling Psychologist provided the program using tele-health platforms.

Results

Of the 66 subjects (55 ± 13 years, 73% male), 17 (26%) enrolled pre-pandemic and 49 (74%) enrolled during-pandemic, 28 (42%) were HBPP and 38 (58%) were HBCR participants. Majority of the subjects (n = 51, 77%), with significantly more HBCR than HBPP participants, harboured 4 or more risk factors (p = 0.04). In the 60 (91%) program completers, BMI, 6MWD, PCS and MCS had improved significantly. SBP, DBP, LVEF, HbA1c, total cholesterol and LDL had improved significantly in affected subjects. Completely home-based participants (n = 44, 67%) who never had any in-person contact with the team during the program also showed significant improvement. No adverse events were reported.

Conclusion

Comprehensive home-based CVD prevention programs are effective in improving anthropometric, clinical, biochemical and psychosocial parameters, are a safe alternative to conventional programs and could potentially become the standard-of-care in the post-pandemic era.

A survey-based comparison of cardiovascular health risk behaviours in Indian men and women during the pandemic

Funding Acknowledgements

Type of funding sources: None.

Background

Cardiovascular disease (CVD), the leading cause of mortality globally, is caused by a combination of behavioral, clinical and genetic risk factors. The rising prevalence of unhealthy diet, inadequate exercise, psychosocial factors and tobacco use in urban and rural populations of India has posed a major epidemiological and healthcare threat in the recent past.

Purpose

This study aims to understand the cardiovascular health risk behaviors in Indian men and women during the pandemic.

Methods

A survey-based study was conducted at different time points between April 2020 and August 2021. A pre-tested anonymized self-administered questionnaire was distributed online as a pre-program assessment of participants registering for the health awareness webinars conducted by our team. Demographic data and CVD risk behaviors pertaining to dietary consumption, exercise routine, sedentary behavior, psychosocial factors, sleep pattern, tobacco use and alcohol consumption were collected. Not meeting daily intake of whole grains and at least 4 portions of vegetables and fruits, non-performance of at least 150 minutes of brisk aerobic exercise per week, chronic stress and use of tobacco were considered risky behaviors, as per the international guidelines.

Results

Of the 573 subjects, 305 (53%) were women and 236 (41%) were 15-30 years old. Majority of subjects were not meeting their requirements pertaining to whole grains (76%) and fruits/vegetables (72%). Inadequate exercise (48%), chronic stress (31%) and tobacco use (5%) were noted. Significantly more women than men (p = 0.0001) were falling short in their exercise requirement. Significantly more men than women (p = 0.0001) were using tobacco products (Figure).

Conclusion

Cardiovascular risk behaviors are highly prevalent in Indian men and women during the pandemic calling for a coordinated effort to increase awareness and modify to a healthy behavior. Abstract Figure. Risk behaviors in study subjects  Abstract Figure. Comparison of risk behaviors

Co-emergence of cardiac and gut tissues promotes cardiomyocyte maturation within human iPSC-derived organoids

During embryogenesis, paracrine signaling between tissues in close proximity contributes to the determination of their respective cell fate(s) and development into functional organs. Organoids are in vitro models that mimic organ formation and cellular heterogeneity, but lack the paracrine input of surrounding tissues. Here, we describe a human multilineage iPSC-derived organoid that recapitulates cooperative cardiac and gut development and maturation, with extensive cellular and structural complexity in both tissues. We demonstrate that the presence of endoderm tissue (gut/intestine) in the organoids contributed to the development of cardiac tissue features characteristic of stages after heart tube formation, including cardiomyocyte expansion, compartmentalization, enrichment of atrial/nodal cells, myocardial compaction, and fetal-like functional maturation. Overall, this study demonstrates the ability to generate and mature cooperative tissues originating from different germ lineages within a single organoid model, an advance that will further the examination of multi-tissue interactions during development, physiological maturation, and disease.

Provision of a local anaesthetic minor procedures service by surgical advanced clinical practitioners: 5-year study

BACKGROUND

Surgical advanced clinical practitioners (SACPs) form part of the extended surgical workforce drawn from a variety of allied healthcare backgrounds. The primary aim of this study was to determine whether there was a financial benefit in having minor surgical procedures undertaken by dedicated SACPs compared with operating lists assigned to consultant surgeons.

METHODS

This was a retrospective cohort study including all patients who had minor 'lumps and bumps' procedures undertaken between April 2014 and August 2019 at East Lancashire Hospitals NHS Trust under local anaesthetic by the general surgery team. Clinical patient information, including lesion type, was collected along with operating room staffing levels and duration of operation. The cost of the procedure was calculated as operating time multiplied by cost of staff per minute according to local banding.

RESULTS

A total of 1399 patients had a lesion excised; 907 procedures were carried out by a doctor, and the rest independently by a SACP. The majority of lesions excised were lipomas and cysts. There was no difference in the median surgical time taken between SACPs and doctors (20 (i.q.r. 14-28) min). Minor procedures carried out on consultant surgeon lists cost 62.3 per cent (€25.33) more on average than those on SACP lists (median €65.96 versus 40.63 respectively; P < 0.001).

CONCLUSION

A dedicated and independent SACP 'lumps and bumps' list was financially beneficial. Operating times were similar to those of doctors. These lists safely free trainee and consultant surgeons to undertake more complex work.

SECs (Sinusoidal Endothelial Cells), Liver Microenvironment, and Fibrosis

Liver fibrosis is a wound-healing response to chronic liver injury such as alcoholic/nonalcoholic fatty liver disease and viral hepatitis with no FDA-approved treatments. Liver fibrosis results in a continual accumulation of extracellular matrix (ECM) proteins and paves the way for replacement of parenchyma with nonfunctional scar tissue. The fibrotic condition results in drastic changes in the local mechanical, chemical, and biological microenvironment of the tissue. Liver parenchyma is supported by an efficient network of vasculature lined by liver sinusoidal endothelial cells (LSECs). These nonparenchymal cells are highly specialized resident endothelial cell type with characteristic morphological and functional features. Alterations in LSECs phenotype including lack of LSEC fenestration, capillarization, and formation of an organized basement membrane have been shown to precede fibrosis and promote hepatic stellate cell activation. Here, we review the interplay of LSECs with the dynamic changes in the fibrotic liver microenvironment such as matrix rigidity, altered ECM protein profile, and cell-cell interactions to provide insight into the pivotal changes in LSEC physiology and the extent to which it mediates the progression of liver fibrosis. Establishing the molecular aspects of LSECs in the light of fibrotic microenvironment is valuable towards development of novel therapeutic and diagnostic targets of liver fibrosis.

Marine Enzymes and Microorganisms for Bioethanol Production

Bioethanol is a potential alternative fuel to fossil fuels. Bioethanol as a fuel has several economic and environmental benefits. Though bioethanol is produced using starch and sugarcane juice, these materials are in conflict with food availability. To avoid food-fuel conflict, the second-generation bioethanol production by utilizing nonfood lignocellulosic materials has been extensively investigated. However, due to the complexity of lignocellulose architecture, the process is complicated and not economically competitive. The cultivation of lignocellulosic energy crops indirectly affects the food supplies by extensive land use. Marine algae have attracted attention to replace the lignocellulosic feedstock for bioethanol production, since the algae grow fast, do not use land, avoid food-fuel conflict and have several varieties to suit the cultivation environment. The composition of algae is not as complex as lignocellulose due to the absence of lignin, which renders easy hydrolysis of polysaccharides to fermentable sugars. Marine organisms also produce cold-active enzymes for hydrolysis of starch, cellulose, and algal polysaccharides, which can be employed in bioethanol process. Marine microoorganisms are also capable of fermenting sugars under high salt environment. Therefore, marine biocatalysts are promising for development of efficient processes for bioethanol production.

ID: 115: TRKA TRANSACTIVATION BY LYSOPHOSPHATIDIC ACID REGULATES LUNG EPITHELIAL CELL MIGRATION

Background

Lysophosphatidic acid (LPA) is a bioactive lysophospholipid, which plays a crucial role in cell proliferation, migration, and differentiation. LPA exerts its biological effects mainly through cell-surface LPA receptors (LPA1-6), which belong to the G protein-coupled receptor (GPCR) family. Recent studies suggest that cross-talk between receptor tyrosine kinases (RTKs) and GPCRs modulates GPCR-mediated signaling. TrkA receptor is a RTK, which mediates nerve growth factor (NGF)-induced biological functions including cell migration in neuronal and non-neuronal tissues.

Methods and Results

Here, we show that LPA treatment of the murine lung epithelial cell line (MLE-12 cells) induced tyrosine phosphorylation of TrkA in both time- and dose-dependent manners. These effects were attenuated by downregulating the LPA1 receptor. Furthermore, LPA induces interaction between LPA1 and TrkA. Co-immunoprecipitation experiment reveals that c-terminus of LPA1 contains the binding site for TrkA. Further, we found that LPA1 and phosphorylated TrkA were co-localized in both the plasma membrane and cytoplasm. Pretreatment with a TrkA inhibitor attenuated LPA-induced phosphorylation of TrkA receptor and LPA1 internalization as well as lung epithelial cell migration.

Conclusion

These studies reveal a molecular mechanism for the transactivation of TrkA by LPA, and suggest that the cross-talk between LPA1 and TrkA regulates LPA-induced receptor internalization and lung epithelial cell migration.

This work was supported by the National Institutes of Health (R01HL091916 and R01HL112791 to Y.Z, R01GM115389 to J.Z.), American Heart Association 12SDG9050005 (J.Z.), American Lung Association Biomedical Research Grant RG350146 (J.Z.).

ID: 123: ROLE OF MICRORNA-1 IN REGULATING PULMONARY VASCULAR REMODELING IN PULMONARY ARTERIAL HYPERTENSION

Rationale

Pulmonary arterial hypertension (PAH) is a severe, progressive disease characterized by increased pulmonary arterial pressure and resistance due in part to uncontrolled vascular remodeling. The mechanisms contributing to vascular remodeling in PAH are poorly understood and involve rampant pulmonary artery smooth muscle cell (PASMC) proliferation. We recently demonstrated the important role of sphingosine kinase 1 (SphK1), a lipid kinase producing pro-proliferative sphingosine-1-phosphate (S1P), in the development of pulmonary vascular remodeling in PAH. However, the regulatory processes involved in upregulation of SphK1 in this disease are unknown.

Objective

In this study, we aimed to identify novel molecular mechanisms governing the regulation of SphK1 expression, with a focus on microRNA (miR). Using both in vitro studies in pulmonary artery smooth muscle cells (PASMCs) and an in vivo mouse model of experimental hypoxia-mediated pulmonary hypertension (HPH), we explored the role of miR in controlling SphK1 expression in the development of pulmonary vascular remodeling.

Methods and Results

In silico analysis identified hsa-miR-1-3p (miR-1) as a candidate targeting SphK1. We demonstrate miR-1 is down-regulated by hypoxia in human PASMCs and in lung tissues of mice with HPH, coinciding with upregulation of SphK1 expression. PASMCs isolated from patients with PAH had significantly reduced expression of miR-1. Transfection of human PASMCs with miR-1 mimics significantly attenuated activity of a SphK1-3'-UTR luciferase reporter construct and SphK1 protein expression. miR-1 overexpression in human PASMCs also inhibited proliferation and migration under normoxic and hypoxic conditions, both important in pathogenic vascular remodeling in PAH. Finally, we demonstrated that intravenous administration of miR-1 mimics prevents the development of experimental HPH in mice and attenuates induction of SphK1 in PASMCs.

Conclusion

These data demonstrate that miR-1 expression in reduced in PASMCs from PAH patients, is modulated by hypoxia, and regulates the expression of SphK1. Key phenotypic aspects of vascular remodeling are influenced by miR-1 and its overexpression can prevent the development of HPH in mice. These studies further our understanding of the mechanisms underlying pathogenic pulmonary vascular remodeling in PAH and could lead to novel therapeutic targets.

Supported by grants NIH/NHLBI R01 HL127342 and R01 HL111656 to RFM, NIH/NHLBI P01 HL98050 and R01 HL127342 to VN, American Heart Association Predoctoral Fellowship (15PRE2190004) to JRS, and NIH/NLHBI NRSA F30 Fellowship (FHL128034A) to JRS.

ID: 112: ROLE OF PHOSPHOLIPASE D IN IDIOPATHIC PULMONARY FIBROSIS

Idiopathic pulmonary fibrosis (IPF) is a deadly interstitial disease that leads to scarring and fibrosis of the lung tissue. In pulmonary fibrosis, there is injury and denudation of the alveolar epithelium, which further leads to activation of fibroblasts which differentiate into myofibroblasts. This includes several mechanisms including epithelial to mesenchymal transition (EMT). In this study, we investigated the role of phospholipase D (PLD) in IPF and also its underlying mechanism like EMT and fibroblast proliferation and differentiation. An in vivo murine model of bleomycin-induced pulmonary fibrosis (PF) and in vitro models of murine alveolar type-II epithelial cells (MLE-12) and human lung fibroblasts were used. C57BL/6 and genetically engineered PLD2−/− mice were intratracheally challenged with bleomycin (1.5 U/kg animal) for 14 days and markers of inflammation, EMT and fibrosis were determined. MLE-12 cells were treated with specific PLD1 or PLD2 inhibitors prior to bleomycin (10 mU/ml) challenge, and the role of PLD in EMT and apoptosis of alveolar epithelial cells was studied. Human lung fibroblasts were serum-starved (3h), pretreated with PLD1 or PLD2 inhibitors, and the effect of TGF-β (5 ng/ml) on differentiation of lung fibroblast to myofibroblast was determined. Intra-tracheal instillation of bleomycin in the mice for 14 days leads to the progression of fibrosis in the lung. The lung tissues of the bleomycin treated mice were found to have increased PLD2 protein expression, myofibroblast markers like α-SMA, fibronectin, mesenchymal markers like vimentin, inflammatory cytokines and collagen. Genetic deletion of PLD2 in mice attenuated bleomycin-induced lung inflammation and pulmonary fibrosis. In vitro, MLE-12 cells pretreated with either PLD1 or PLD2 inhibitor did not show a profound reduction either in apoptosis or the expression of transcription factors such as SNAIL, and other markers of EMT. However, MLE-12 cells pretreated with both PLD1 (250 nM) and PLD2 (500 nM) inhibitors were resistant to bleomycin-induced apoptosis, and exhibited reduced expression of SNAIL and mesenchymal markers. On the contrary, human lung fibroblasts pretreated with PLD1 and PLD2 inhibitors showed increased fibroblast to myofibroblast differentiation mediated by TGF-β. The present study suggests a role for PLD2 in bleomycin-induced PF. In vitro, inhibition of both PLD1 and PLD2 was necessary to attenuate bleomycin-induced EMT in epithelial cells and TGF-β mediated differentiation of fibroblasts to myofibroblasts. The in vivo and in vitro results identify the mechanism by which PLD regualtes PF and suggest PLD as a potential therapeutic target in pulmonary fibrosis. This work was supported by National Institutes of Health grant P01 HL98050 to VN.

ID: 116: ADNIBISTRATION OF SPHINGOSINE KINASE 1 INHIBITOR POST-BLEOMYCIN CHALLENGE ATTENUATES BLEOMYCIN-INDUCED PULMONARY FIBROSIS IN MICE: ROLE OF YAP1

Rationale

We have earlier reported that sphingosine kinase 1 (SphK1) is up-regulated in lung tissues from idiopathic pulmonary fibrosis (IPF) patients and SphK1/sphingosine-1-phosphate (S1P) signaling axis plays a key role in bleomycin- and radiation-induced pulmonary fibrosis in mice. Further, SphK1 mRNA levels in PBMCs from IPF patients directly and significantly correlated with pulmonary function outcomes and overall survival. In this study, we investigated the effect of administration of PF-543, a specific SphK1 inhibitor, 7 days post-bleomycin (BLM) challenge on the development of pulmonary fibrosis in mice.

Objectives

To determine the efficacy of PF-543 in attenuating pulmonary fibrosis in mice post BLM challenge.

Methods

SphK1 inhibitor PF-543 (5 mg/kg body weight, i.p.; twice a week) was administered to control and BLM (1.5 U/kg, intratracheal) challenged mice on day 7 post BLM challenge, and development of pulmonary fibrosis was determined on day 21 by Mason-Trichrome staining of lung tissues, total collagen, fibronectin and α-SMA protein levels in lung tissues. In vitro, the effect of PF-543 on TGF-β (5 ng/ml) induced Yap1 activation, and differentiation, contraction, and proliferation of human lung fibroblast were assessed.

Results

Administration of PF-543 to BLM treated mice on day 7 post challenge, dramatically inhibited BLM-induced lung injury, and attenuated collagen deposition and expression of fibronectin, α-SMA and TGF-β in lung tissues on day 21 post-BLM challenge. In vitro, PF-543 inhibited TGF-β induced differentiation, contraction and proliferation of human lung fibroblasts, as well as blocked TGF-β induced expression and nuclear translocation of YAP, a transcriptional co-factor involved in pulmonary fibrosis. Additionally, siRNA knockdown of YAP1 inhibited TGF-β induced fibroblast differentiation.

Conclusion

These studies demonstrate ability of SphK1 inhibitor, PF-543 to ameliorate BLM-induced pulmonary fibrosis in mice when administered on day 7 after BLM challenge. Also, PF-543 blocked YAP1 activation, a co-transcriptional factor involved in pulmonary fibrosis development. Thus, PF-543 may serve as a potential therapeutic drug in treating pulmonary fibrosis. This work was supported by P01 HL098050 (VN).

ID: 111: THE S1P TRANSPORTER, SPNS2, MEDIATES HGF-INDUCED LAMELLIPODIA FORMATION AND MIGRATION OF HUMAN LUNG ENDOTHELIAL CELLS

Rationale

We have demonstrated earlier that HGF-induced lamellipodia formation in human lung microvascular endothelial cells (HLMVECs) was through c-Met receptor tyrosine kinase and PI3 kinase/Akt signal transduction. Here, we show that HGF-mediated lamellipodia formation is dependent on intracellular S1P generation mediated by sphingosine kinase 1 (SphK1), the S1P transporter, Spns2 and S1P1 in HLMVECs.

Methods

HLMVECs were treated with HGF (20 ng/ml) for different time points. Lamellipodia were detected after HGF treatment by immunofluorescent staining of Spns2, cortactin and actin in lamellipodia, and lamellipodia were quantified by measuring cell periphery fluorescence intensity. Pearson's correlation coefficient was used to statistically quantify co-localization of proteins in lamellipodia. Endogenous SphK activity was blocked by SphK1 specific inhibitor PF-543, and expression of SphK1 in cells was down-regulated by siRNA. Cellular S1P levels were quantified by mass spectrometry.

Results

HGF stimulated phosphorylation of SphK1, and its localization to lamellipodia of HLMVECs. Down-regulation of SphK1, but not SphK2, with siRNA or inhibition of SphK1 with PF-543 (1–5 µM) attenuated HGF-induced lamellipodia formation in HLMVECs. The HGF-mediated phosphorylation of SphK1 and its localization in lamellipodia was dependent on PI3K/Akt and ERK1/2 signaling apthways. HGF increased S1P levels in HLMVECs, which was blocked by inhibition of SphK1 with PF-543. Further, HGF induced serine phosphorylation and translocation of Spns2, the S1P transporter, to lamellipodia, which was Akt dependent. The HGF-induced lamellipodia formation in HLMVECs was blocked by down-regulation of Spns2, suggesting extracellular action of S1P in lamellipodia formation. Down-regulation of S1P1, but not S1P2 or S1P3, with siRNA attenuated HGF-induced lamellipodia formation. Further, HGF stimulation enhanced association of Spns2 with S1P1 and blocking SphK1 activty with PF-543 attenuated the association between Spns2 and S1P1. Additionally, HGF-induced migration of HLMVECs was attenuated by down-regulation of Spns2.

Conclusion

These results suggest that HGF/c-Met mediated lamellipodia formation and motility is dependent on intracellular generation of S1P via activation and localization of SphK1 to cell periphery and Spns2 mediated transport of S1P to outside for signaling via S1P1 in HLMVECs. This work was supported by NIH/HLBI P01 HL98050 to VN.

ID: 120: REGULATION OF ENDOTHELIAL BARRIER PERMEABILITY BY PHOSPHOLIPASE D2

Pulmonary edema is a hallmark of several diseases including acute respiratory distress syndrome (ARDS) and is characterized by the disruption of the pulmonary endothelial barrier at its early stage. Maintaining the integrity of the adherens junctions (AJs) by stabilizing VE-Cadherin (VEC) at the cell membrane after injury could potentially be important to minimize endothelial barrier disruption. Since Phospholipase D (PLD) and its catalytic product, phosphatidic acid (PA), has been shown to be critical in membrane trafficking and in recycling of a number of cell surface receptors, we hypothesized that PLD/PA pathway accelerates the rate of VEC recycling to the lamellipodia to reassemble the AJs. We demonstrate, by measuring the trans endothelial resistance of human lung microvascular endothelial cells (HLMVECs), that inhibiting PLD2-dependent PA production increases the endothelium permeability in response to thrombin. Furthermore, immunostaining shows that the uniform redistribution of VEC to the AJs post thrombin insult is compromised when PLD-dependent PA production is inhibited, and resulted in the appearance of eminent intercellular gaps. Also, PLD2 inhibition prevented the HLMVECs from fully spreading after thrombin stimulation while the protrusive activity remained unaffected, suggesting that PLD2 is not required by HLMVECs to send protrusions, but is critical for the adherence of the protrusions. LPS-induced lung injury was more severe in PLD2 knockout mice compared to WT in an in vivo ARDS model. These observations suggest that PLD/PA signaling plays an important role in resealing of endothelial gaps post LPS-induced lung injury and could potentially be therapeutically utilized to enhance post-injury endothelium recovery.

ID: 130: NOVEL ROLE FOR LYSOCARDIOLIPIN ACYLTRANSFERASE (LYCAT) IN NON-SMALL CELL LUNG CANCER

Lung cancer is the leading cause of deaths in United States and non-small cell lung cancer (NSCLC) accounts for ∼85% of all lung cancers with a 5-year survival rate of approximately ∼16%. Therefore there is an immediate need to develop new strategies for early detection and more effective treatments options. Mitochondrial dysfunction including but not limited to defects in mitochondrial genomics and dynamics has long been implicated to play a role in human health and disease particularly in cancer initiation, progression and treatment options since it plays a pivotal role in cell death and survival. Lysocardiolipin acyltransferase (LYCAT), a Cardiolipin remodeling enzyme regulating the 18:2 linoleic acid pattern of mammalian mitochondrial cardiolipin, plays a crucial role in maintaining normal mitochondrial function and vascular development. LYCAT was shown to be up-regulated in cancers; however, the role of LYCAT in lung cancer is yet unclear. Probing the protein expression of LYCAT in lung cancer specimens, non-transformed bronchial epithelial cell lines and 5 lung cancer cell lines revealed increased LYCAT expression and activity in all the lung cancer samples and cell lines tested in comparison to the control lung tissues and non-transformed epithelial cell lines. To determine the role of LYCAT in lung cancer, NSCLC cell lines H2122 and H23 were transfected with either scrambled or LYCAT shRNA and differences in serum-induced cell proliferation, migration, clonogenecity and mitochondrial dynamics were determined. Our results demonstrated that down-regulation of LYCAT by shRNA significantly attenuated cell migration, proliferation, and invasion in NSCLC cell lines compared to control cell lines. Furthermore knockdown of LYCAT expression in NSCLC cell lines inhibited mitochondrial fragmentation and enhanced mitochondrial fusion. Taken together, these data demonstrate a strong association between increased LYCAT expression and cell proliferation, motility, invasion and mitochondrial dynamics in NSCLC cells. Thus, development of targeted therapies to reduce LYCAT expression in NSCLC should be beneficial. This work in part was supported by funds from the College of Medicine, UIC and NIH HL98050 to VN.

Evaluation of terrestrial plants extracts for uranium sorption and characterization of potent phytoconstituents

Sorption capacity of four plants (Funaria hygrometrica, Musa acuminata, Brassica juncea and Helianthus annuus) extracts/fractions for uranium, a radionuclide was investigated by EDXRF and tracer studies. The maximum sorption capacity, i.e., 100% (complete sorption) was observed in case of Musa acuminata extract and fractions. Carbohydrate, proteins, phenolics and flavonoids contents in the active fraction (having maximum sorption capacity) were also determined. Further purification of the most active fraction provided three pure molecules, mannitol, sorbitol and oxo-linked potassium oxalate. The characterization of isolated molecules was achieved by using FTIR, NMR, GC-MS, MS-MS, and by single crystal-XRD analysis. Of three molecules, oxo-linked potassium oxalate was observed to have 100% sorption activity. Possible binding mechanism of active molecule with the uranyl cation has been purposed.

Mitochondrial dysfunction and loss of glutamate uptake in primary astrocytes exposed to titanium dioxide nanoparticles

Titanium dioxide (TiO2) nanoparticles are currently the second most produced engineered nanomaterial in the world with vast usage in consumer products leading to recurrent human exposure. Animal studies indicate significant nanoparticle accumulation in the brain while cellular toxicity studies demonstrate negative effects on neuronal cell viability and function. However, the toxicological effects of nanoparticles on astrocytes, the most abundant cells in the brain, have not been extensively investigated. Therefore, we determined the sub-toxic effect of three different TiO2 nanoparticles (rutile, anatase and commercially available P25 TiO2 nanoparticles) on primary rat cortical astrocytes. We evaluated some events related to astrocyte functions and mitochondrial dysregulation: (1) glutamate uptake; (2) redox signaling mechanisms by measuring ROS production; (3) the expression patterns of dynamin-related proteins (DRPs) and mitofusins 1 and 2, whose expression is central to mitochondrial dynamics; and (4) mitochondrial morphology by MitoTracker® Red CMXRos staining. Anatase, rutile and P25 were found to have LC50 values of 88.22 ± 10.56 ppm, 136.0 ± 31.73 ppm and 62.37 ± 9.06 ppm respectively indicating nanoparticle specific toxicity. All three TiO2 nanoparticles induced a significant loss in glutamate uptake indicative of a loss in vital astrocyte function. TiO2 nanoparticles also induced an increase in reactive oxygen species generation, and a decrease in mitochondrial membrane potential, suggesting mitochondrial damage. TiO2 nanoparticle exposure altered expression patterns of DRPs at low concentrations (25 ppm) and apoptotic fission at high concentrations (100 ppm). TiO2 nanoparticle exposure also resulted in changes to mitochondrial morphology confirmed by mitochondrial staining. Collectively, our data provide compelling evidence that TiO2 nanoparticle exposure has potential implications in astrocyte-mediated neurological dysfunction.

Substrate stiffness regulates primary hepatocyte functions

Liver fibrosis occurs as a consequence of chronic injuries from viral infections, metabolic disorders, and alcohol abuse. Fibrotic liver microenvironment (LME) is characterized by excessive deposition and aberrant turnover of extracellular matrix proteins, which leads to increased tissue stiffness. Liver stiffness acts as a vital cue in the regulation of hepatic responses in both healthy and diseased states; however, the effect of varying stiffness on liver cells is not well understood. There is a critical need to engineer in vitro models that mimic the liver stiffness corresponding to various stages of disease progression in order to elucidate the role of individual cellular responses. Here we employed polydimethyl siloxane (PDMS) based substrates with tunable mechanical properties to investigate the effect of substrate stiffness on the behavior of primary rat hepatocytes. To recreate physiologically relevant stiffness, we designed soft substrates (2 kPa) to represent the healthy liver and stiff substrates (55 kPa) to represent the diseased liver. Tissue culture plate surface (TCPS) served as the control substrate. We observed that hepatocytes cultured on soft substrates displayed a more differentiated and functional phenotype for a longer duration as compared to stiff substrates and TCPS. We demonstrated that hepatocytes on soft substrates exhibited higher urea and albumin synthesis. Cytochrome P450 (CYP) activity, another critical marker of hepatocytes, displayed a strong dependence on substrate stiffness, wherein hepatocytes on soft substrates retained 2.7 fold higher CYP activity on day 7 in culture, as compared to TCPS. We further observed that an increase in stiffness induced downregulation of key drug transporter genes (NTCP, UGT1A1, and GSTM-2). In addition, we observed that the epithelial cell phenotype was better maintained on soft substrates as indicated by higher expression of hepatocyte nuclear factor 4α, cytokeratin 18, and connexin 32. These results indicate that the substrate stiffness plays a significant role in modulating hepatocyte behavior. Our PDMS based liver model can be utilized to investigate the signaling pathways mediating the hepatocyte-LME communication to understand the progression of liver diseases.

Titanium Dioxide Nanoparticles Trigger Loss of Function and Perturbation of Mitochondrial Dynamics in Primary Hepatocytes

Titanium dioxide (TiO2) nanoparticles are one of the most highly manufactured and employed nanomaterials in the world with applications in copious industrial and consumer products. The liver is a major accumulation site for many nanoparticles, including TiO2, directly through intentional exposure or indirectly through unintentional ingestion via water, food or animals and increased environmental contamination. Growing concerns over the current usage of TiO2 coupled with the lack of mechanistic understanding of its potential health risk is the motivation for this study. Here we determined the toxic effect of three different TiO2 nanoparticles (commercially available rutile, anatase and P25) on primary rat hepatocytes. Specifically, we evaluated events related to hepatocyte functions and mitochondrial dynamics: (1) urea and albumin synthesis using colorimetric and ELISA assays, respectively; (2) redox signaling mechanisms by measuring reactive oxygen species (ROS) production, manganese superoxide dismutase (MnSOD) activity and mitochondrial membrane potential (MMP); (3) OPA1 and Mfn-1 expression that mediates the mitochondrial dynamics by PCR; and (4) mitochondrial morphology by MitoTracker Green FM staining. All three TiO2 nanoparticles induced a significant loss (p < 0.05) in hepatocyte functions even at concentrations as low as 50 ppm with commercially used P25 causing maximum damage. TiO2 nanoparticles induced a strong oxidative stress in primary hepatocytes. TiO2 nanoparticles exposure also resulted in morphological changes in mitochondria and substantial loss in the fusion process, thus impairing the mitochondrial dynamics. Although this study demonstrated that TiO2 nanoparticles exposure resulted in substantial damage to primary hepatocytes, more in vitro and in vivo studies are required to determine the complete toxicological mechanism in primary hepatocytes and subsequently liver function.

Effect of solvents on the bulk growth of 4-aminobenzophenone single crystals: a potential material for blue and green lasers

Although 4-aminobenzophenone (4-ABP) is the best derivative of benzophenone with 260 times higher second harmonic generation (SHG) efficiency than potassium dihydrogen phosphate (KDP), growth of high quality bulk crystal still remains a difficult task. In the present work, the effect of solvents on solubility and growth aspects of 4-ABP was investigated to grow inclusion free 4-ABP crystals. The growth processes were discussed based on solute-solvent interaction in two different growth media of ethyl acetate and ethanol. The growth rate and thereby solvent inclusions are relatively higher in ethyl acetate grown crystal than the crystal grown from ethanol. The structural, thermal and optical properties of 4-ABP crystals were studied. The enthalpy of 4-ABP melting process was estimated from differential thermal analysis. The optical transmission study shows that 4-ABP crystals grown from ethanol has high transparency compared to ethyl acetate grown sample due to solvent inclusion in the later crystal.

Structural characterization of titania by X-ray diffraction, photoacoustic, Raman spectroscopy and electron paramagnetic resonance spectroscopy

A titania mineral (obtained from East coast, Orissa, India) was investigated by X-ray diffraction (XRD), photoacoustic spectroscopy (PAS), Raman and Electron Paramagnetic Resonance (EPR) studies. XRD studies indicated the presence of rutile (91%) and anatase (9%) phases in the mineral. Raman investigation supported this information. Both rutile and anatase phases have tetragonal structure (rutile: space group P4(2)/mnm, a=4.5946(1) Å, c=2.9597(1) Å, V=62.48(1) (Å)(3), Z=2; anatase: space group I4(1)/amd, 3.7848(2) Å, 9.5098(11) Å, V=136.22(2) (Å)(3), Z=4). The deconvoluted PAS spectrum showed nine peaks around 335, 370, 415,485, 555, 605, 659, 690,730 and 785 nm and according to the ligand field theory, these peaks were attributed to the presence of V(4+), Cr(3+), Mn(4+) and Fe(3+) species. EPR studies revealed the presence of transition metal ions V(4+)(d(1)), Cr(3+)(d(3)), Mn(4+)(d(3)) and Fe(3+)(d(5)) at Ti(4+) sites. The EPR spectra are characterized by very large crystal filed splitting (D term) and orthorhombic distortion term (E term) for multiple electron system (s>1) suggesting that the transition metal ions substitute the Ti(4+) in the lattice which is situated in distorted octahedral coordination of oxygen. The possible reasons for observation of unusually large D and E term in the EPR spectra of transition metal ions (S=3/2 and 5/2) are discussed.

Synthesis of a flexible poly(chloroprene)/methyl red film dosimeter using an environment-benign shear compounding method

The paper reports synthesis of a new film dosimeter based on a solvent-free route. Methyl red (MR) dye was introduced into poly(chloroprene) (PC) in various concentrations. The films were intensely red with λmax ~515nm. The absorbance decreased linearly with absorbed radiation dose up to 30kGy without a significant change in λmax. Color coordinates of the films were also analyzed. Optical micrographs of the films showed no signs of inhomogeneous distribution of MR in the PC matrix, which was attributed to the polarity of PC. Radiation sensitivity, dose response linearity, effects of irradiation temperature and humidity, as well as the rate of fading, were also investigated.

Probing local site environments and distribution of manganese in SrZrO3:Mn; PL and EPR spectroscopy complimented by DFT calculations

In order to understand the local environment, valence state and distribution of manganese; a combined experimental and theoretical approach based on PL, EPR and DFT is reported for Sr_(1−x)Zr_(1−y)Mn_(x+y)O₃, also explaining the origin of various defect related emissions.

Intense red emitting monoclinic LaPO4:Eu3+ nanoparticles: host–dopant energy transfer dynamics and photoluminescence properties

Visible host emission and dynamics of host–dopant energy transfer in LaPO₄:Eu phosphor is investigated using PL and complimented by DFT.

The role of reaction conditions in the polymorphic control of Eu3+ doped YInO3: structure and size sensitive luminescence

Controlled synthetic conditions yielded YInO₃:Eu³⁺ in both C-type and hexagonal modifications which exhibited a tremendous bearing of size and local structure on Eu³⁺ luminescence, all in a single compound.

Design of Content Based Image Retrieval Scheme for Diabetic Retinopathy Images using Harmony Search Algorithm

Diabetic Retinopathy (DR) is a disorder that affects the structure of retinal blood vessels due to long-standing diabetes mellitus. Automated segmentation of blood vessel is vital for periodic screening and timely diagnosis. An attempt has been made to generate continuous retinal vasculature for the design of Content Based Image Retrieval (CBIR) application. The typical normal and abnormal retinal images are preprocessed to improve the vessel contrast. The blood vessels are segmented using evolutionary based Harmony Search Algorithm (HSA) combined with Otsu Multilevel Thresholding (MLT) method by best objective functions. The segmentation results are validated with corresponding ground truth images using binary similarity measures. The statistical, textural and structural features are obtained from the segmented images of normal and DR affected retina and are analyzed. CBIR in medical image retrieval applications are used to assist physicians in clinical decision-support techniques and research fields. A CBIR system is developed using HSA based Otsu MLT segmentation technique and the features obtained from the segmented images. Similarity matching is carried out between the features of query and database images using Euclidean Distance measure. Similar images are ranked and retrieved. The retrieval performance of CBIR system is evaluated in terms of precision and recall. The CBIR systems developed using HSA based Otsu MLT and conventional Otsu MLT methods are compared. The retrieval performance such as precision and recall are found to be 96% and 58% for CBIR system using HSA based Otsu MLT segmentation. This automated CBIR system could be recommended for use in computer assisted diagnosis for diabetic retinopathy screening.

Optical properties of ammonium uranyl fluoride characterized by photoluminescence and photoacoustic spectroscopy

PL and PAS studies were performed on uranyl compounds viz. uranium oxalate, uranium fluoride and ammonium uranyl fluoride. PL and PAS spectrum of ammonium uranyl fluoride is being reported for the first time. Ammonium uranyl fluoride is blue shifted with respect to uranyl fluoride, as a result of ammonium bonding. The vibronic separations were determined in the excited state and the ground state using excitation/PA spectra and emission spectra respectively. Fluorescence decay data could be fitted only with biexponential decay in all of these compounds indicating the presence of two different environments in these compounds. Low temperature luminescence leads to enhancement in emission intensity and lifetime value. The temperature dependence studies of average fluorescence lifetimes of ammonium uranyl are described in this paper. Based on this studies activation energy value for ammonium uranyl fluoride at which (3)∏ and (1)Σ potential surfaces will cross is calculated.

Understanding the local environment of Sm3+ in doped SrZrO3 and energy transfer mechanism using time-resolved luminescence: a combined theoretical and experimental approach

A combined experimental and theoretical study on the photoluminescence (PL) properties of strontium zirconate (SZ) and Sm³⁺ doped SZ nanostructures is presented in this work.