Perilipin 2 (PLIN2)-Deficiency Does Not Increase Cholesterol-Induced Toxicity in Macrophages

Interventions on macrophages/foam cells to redirect intracellular cholesterol towards efflux pathways could become a very valuable addition to our therapeutic arsenal against atherosclerosis. However, certain manipulations of the cholesteryl ester cycle, such as the inhibition of ACAT1, an ER-resident enzyme that re-esterifies cholesterol, are not well tolerated. Previously we showed that targeting perilipin-2 (PLIN2), a major lipid droplet (LD)-associated protein in macrophages, prevents foam cell formation and protects against atherosclerosis. Here we have assessed the tolerance of PLIN2-deficient bone marrow derived macrophages (BMM) to several lipid loading conditions similar to the found during atherosclerosis development, including exposure to modified low-density lipoprotein (mLDL) and 7-ketocholesterol (7-KC), a free cholesterol (FC) metabolite, in media with or without cholesterol acceptors. BMM isolated from mice that do or do not express PLIN2 were tested for apoptosis (TUNEL and cleaved caspase-3), ER stress (CHOP induction and XBP-1 splicing), and inflammation (TNF-α and IL-6 mRNA levels). Like in other cell types, PLIN2 deficiency impairs LD buildup in BMM. However, while most stress parameters were elevated in macrophages under ACAT inhibition and 7-KC loading, PLIN2 inactivation was well tolerated. The data support the safety of targeting PLIN2 to prevent foam cell formation and atherosclerosis

A new technique for seeding chondrocytes onto solvent-preserved human meniscus using the chemokinetic effect of recombinant human bone morphogenetic protein-2

Many investigators are currently studying the use of decellularized tissue allografts from human cadavers as scaffolds onto which patients’ cells could be seeded, or as carriers for genetically engineered cells to aid cell transplantation. However, it is difficult to seed cells onto very dense regular connective tissue which has few interstitial spaces. Here, we discuss the development of a chemotactic cell seeding technique using solvent-preserved human meniscus. A chemokinetic response to recombinant human bone morphogenetic protein-2 (rhBMP-2) was observed in a monolayer culture of primary chondrocytes derived from femoral epiphyseal cartilage of 2-day-old rats. The rhBMP-2 significantly increased their migration upto 10 ng/ml in a dose-dependent manner. When tested with solvent-preserved human meniscus as a scaffold, which has few interstitial spaces, rhBMP-2 was able to induce chondrocytes to migrate into the meniscus. After a 3-week incubation, newly-formed cartilaginous extracellular matrix was synthesized by migrated chondrocytes throughout the meniscus, down to a depth of 3 mm. These findings demonstrate that rhBMP-2 may be a natural chemokinetic factor in vivo, which induces migration of proliferative chondrocytes into the narrow interfibrous spaces. Our results suggest a potential application of rhBMP-2 for the designed distribution of chondrocytes into a scaffold to be used for tissue engineering

C16 ceramide is crucial for triacylglycerol-induced apoptosis in macrophages

Triacylglycerol (TG) accumulation caused by adipose triglyceride lipase (ATGL) deficiency or very low-density lipoprotein (VLDL) loading of wild-type (Wt) macrophages results in mitochondrial-mediated apoptosis. This phenotype is correlated to depletion of Ca2+ from the endoplasmic reticulum (ER), an event known to induce the unfolded protein response (UPR). Here, we show that ER stress in TG-rich macrophages activates the UPR, resulting in increased abundance of the chaperone GRP78/BiP, the induction of pancreatic ER kinase-like ER kinase, phosphorylation and activation of eukaryotic translation initiation factor 2A, the translocation of activating transcription factor (ATF)4 and ATF6 to the nucleus and the induction of the cell death executor CCAAT/enhancer-binding protein homologous protein. C16:0 ceramide concentrations were increased in Atgl–/– and VLDL-loaded Wt macrophages. Overexpression of ceramide synthases was sufficient to induce mitochondrial apoptosis in Wt macrophages. In accordance, inhibition of ceramide synthases in Atgl–/– macrophages by fumonisin B1 (FB1) resulted in specific inhibition of C16:0 ceramide, whereas intracellular TG concentrations remained high. Although the UPR was still activated in Atgl–/– macrophages, FB1 treatment rescued Atgl–/– macrophages from mitochondrial dysfunction and programmed cell death. We conclude that C16:0 ceramide elicits apoptosis in Atgl–/– macrophages by activation of the mitochondrial apoptosis pathway

Effective Rheology of Bubbles Moving in a Capillary Tube

We calculate the average volumetric flux versus pressure drop of bubbles moving in a single capillary tube with varying diameter, finding a square-root relation from mapping the flow equations onto that of a driven overdamped pendulum. The calculation is based on a derivation of the equation of motion of a bubble train from considering the capillary forces and the entropy production associated with the viscous flow. We also calculate the configurational probability of the positions of the bubbles.Comment: 4 pages, 1 figur

Nonadhesive Culture System as a Model of Rapid Sphere Formation with Cancer Stem Cell Properties

BACKGROUND: Cancer stem cells (CSCs) play an important role in tumor initiation, progression, and metastasis and are responsible for high therapeutic failure rates. Identification and characterization of CSC are crucial for facilitating the monitoring, therapy, or prevention of cancer. Great efforts have been paid to develop a more effective methodology. Nevertheless, the ideal model for CSC research is still evolving. In this study, we created a nonadhesive culture system to enrich CSCs from human oral squamous cell carcinoma cell lines with sphere formation and to characterize their CSC properties further. METHODS: A nonadhesive culture system was designed to generate spheres from the SAS and OECM-1 cell lines. A subsequent investigation of their CSC properties, including stemness, self-renewal, and chemo- and radioresistance in vitro, as well as tumor initiation capacity in vivo, was also performed. RESULTS: Spheres were formed cost-effectively and time-efficiently within 5 to 7 days. Moreover, we proved that these spheres expressed putative stem cell markers and exhibited chemoradiotherapeutic resistance, in addition to tumor-initiating and self-renewal capabilities. CONCLUSIONS: Using this nonadhesive culture system, we successfully established a rapid and cost-effective model that exhibits the characteristics of CSCs and can be used in cancer research

Providing High-Quality Care for Limited English Proficient Patients: The Importance of Language Concordance and Interpreter Use

Background: Provider–patient language discordance is related to worse quality care for limited English proficient (LEP) patients who speak Spanish. However, little is known about language barriers among LEP Asian-American patients. Objective: We examined the effects of language discordance on the degree of health education and the quality of interpersonal care that patients received, and examined its effect on patient satisfaction. We also evaluated how the presence/absence of a clinic interpreter affected these outcomes. Design: Cross-sectional survey, response rate 74%. Participants: A total of 2,746 Chinese and Vietnamese patients receiving care at 11 health centers in 8 cities. Measurements: Provider–patient language concordance, health education received, quality of interpersonal care, patient ratings of providers, and the presence/absence of a clinic interpreter. Regression analyses were used to adjust for potential confounding. Results: Patients with language-discordant providers reported receiving less health education (β = 0.17, p < 0.05) compared to those with language-concordant providers. This effect was mitigated with the use of a clinic interpreter. Patients with language-discordant providers also reported worse interpersonal care (β = 0.28, p < 0.05), and were more likely to give low ratings to their providers (odds ratio [OR] = 1.61; CI = 0.97–2.67). Using a clinic interpreter did not mitigate these effects and in fact exacerbated disparities in patients’ perceptions of their providers. Conclusion: Language barriers are associated with less health education, worse interpersonal care, and lower patient satisfaction. Having access to a clinic interpreter can facilitate the transmission of health education. However, in terms of patients’ ratings of their providers and the quality of interpersonal care, having an interpreter present does not serve as a substitute for language concordance between patient and provider

Establishment of Fruit Bat Cells (Rousettus aegyptiacus) as a Model System for the Investigation of Filoviral Infection

Marburg virus and several species of Ebola virus are endemic in central Africa and cause sporadic outbreaks in this region with mortality rates of up to 90%. So far, there is no vaccination or therapy available to protect people at risk in these regions. Recently, different fruit bats have been identified as potential reservoirs. One of them is Rousettus aegyptiacus. It seems that within huge bat populations only relatively small numbers are positive for filovirus-specific antibodies or filoviral RNA, a phenomenon that is currently not understood. As a first step towards understanding the biology of filoviruses in bats, we sought to establish a model system to investigate filovirus replication in cells derived from their natural reservoir. Here, we provide the first insights into this topic by monitoring filovirus infection of a Rousettus aegyptiacus derived cell line, R06E. We were able to show that filoviruses propagate well in R06E cells, which can, therefore, be used to investigate replication and transcription of filovirus RNA and to very efficiently perform rescue of recombinant Marburg virus using reverse genetics. These results emphasize the suitability of the newly established bat cell line for filovirus research

Help-Seeking Barriers Among Sexual and Gender Minority Individuals Who Experience Intimate Partner Violence Victimization

Sexual and gender minority (SGM) individuals experience intimate partner violence (IPV) victimization at disproportionate rates compared to cisgender and heterosexual individuals. Given the widespread consequences of experiencing IPV victimization, intervention and prevention strategies should identify readily accessible and culturally competent services for this population. SGM individuals who experience IPV victimization face unique individual-, interpersonal-, and systemic-level barriers to accessing informal and formal support services needed to recover from IPV. This chapter reviews IPV victimization prevalence rates among SGM individuals in the context of minority stress and highlights unique forms of IPV victimization affecting this population, namely identity abuse. The literature on help-seeking processes among IPV survivors in general and help-seeking patterns and barriers specifically among SGM individuals who experience IPV victimization in the context of minority stress (e.g., discrimination, internalized stigma, rejection sensitivity, identity concealment) are discussed. How minority stressors at individual, interpersonal, and structural levels act as barriers to help-seeking among SGM individuals experiencing IPV victimization is presented. The chapter concludes with a review of emerging evidence for interventions aimed at reducing help-seeking barriers among SGM individuals who face IPV victimization and a discussion of future directions for research on help-seeking barriers in this population

British press attitudes towards the EU's global presence:from the Russian-Georgian War to the 2009 Copenhagen Summit

This article surveys the way in which British print media have presented the European Union (EU)'s global presence in the international arena by analysing two case studies which reflect two very distinctive areas of EU foreign policy: global climate change policy and the policy towards Russia. It employs frame analysis, allowing for the identification of the way in which the discourse of the press was categorized around a series of central opinions and ideas. Frames underscore the connections made by journalists between different events, policies or phenomena and their possible interpretations. The analysis highlights that acting through the common framework of the EU rather than unilaterally was a strategy preferred by the British press. These findings are in stark contrast with the deep Euroscepticism which characterizes press attitudes towards most policy areas, and is often considered to be rooted in the British political culture, media system, public opinion or the longstanding tradition of viewing the European continent as the other