Investigation of cell aggregation on the substrate of a parallel-plate flow chamber

Adhesion of tumor cells (TCs) to polymorphonuclear neutrophils (PMNs) tethered on a monolayer of vascular endothelial cells (ECs) in shear flows is investigated theoretically. Both TC—PMN and PMN—EC aggregations are modeled using the population balance equations (PBEs). Parameters in the model obtained by curve fitting show that an increase of shear rate or viscosity will suppress the formation of aggregates and promote the breakage of them. Analysis on the collision frequency suggests that the averaged encounter duration is affected by viscosity. Based on the model, a nonlinear connection between the number of migrated TCs and the concentration of PMNs in the flow near the substrate is presented.

High-throughput screening identifies small molecules that enhance the pharmacological effects of oligonucleotides

The therapeutic use of antisense and siRNA oligonucleotides has been constrained by the limited ability of these membrane-impermeable molecules to reach their intracellular sites of action. We sought to address this problem using small organic molecules to enhance the effects of oligonucleotides by modulating their intracellular trafficking and release from endosomes. A high-throughput screen of multiple small molecule libraries yielded several hits that markedly potentiated the actions of splice switching oligonucleotides in cell culture. These compounds also enhanced the effects of antisense and siRNA oligonucleotides. The hit compounds preferentially caused release of fluorescent oligonucleotides from late endosomes rather than other intracellular compartments. Studies in a transgenic mouse model indicated that these compounds could enhance the in vivo effects of a splice-switching oligonucleotide without causing significant toxicity. These observations suggest that selected small molecule enhancers may eventually be of value in oligonucleotide-based therapeutics.

Correlation-induced self-doping in the iron-pnictide superconductor Ba2Ti2Fe2As4O

The electronic structure of the iron-based superconductor Ba2Ti2Fe2As4O (Tc(onset)=23.5  K) has been investigated by using angle-resolved photoemission spectroscopy and combined local density approximation and dynamical mean field theory calculations. The electronic states near the Fermi level are dominated by both the Fe 3d and Ti 3d orbitals, indicating that the spacer layers separating different FeAs layers are also metallic. By counting the enclosed volumes of the Fermi surface sheets, we observe a large self-doping effect; i.e., 0.25 electrons per unit cell are transferred from the FeAs layer to the Ti2As2O layer, leaving the FeAs layer in a hole-doped state. This exotic behavior is successfully reproduced by our dynamical mean field calculations, in which the self-doping effect is attributed to the electronic correlations in the 3d shells. Our work provides an alternative route of effective doping without element substitution for iron-based superconductors.

Ergonomic Aspects of Clinical and Surgical Procedures

This discussion panel aims to identify ergonomic concerns, solutions and research needs, physical stresses, and outcomes related to clinical and surgical procedures. This session will begin with formal presentations to demonstrate current ergonomic concerns and research initiatives associated with clinical and surgical procedures to frame the panel discussion for the second part of the session. Discussion of different procedures will help to identify solutions and research needs that relate to a broad range of ergonomic problems. Questions will be collected from the attendees and speakers and organized so as to guide the panel discussion and to engage all of the speakers in the discussion to achieve the symposium aims.

Development of RNA aptamer-based therapeutic agents

RNA aptamers are non-coding small RNAs that bind to their cognate targets with high specificity and affinity. They are generally identified by iterative rounds of in vitro selection termed SELEX (Systemic Evolution of Ligands by Exponential Enrichment). Similar to antibodies, they can inhibit, modulate and disrupt the functions of target proteins effectively, making them promising therapeutic agents for the treatment of various diseases and targeted drug delivery. Herein we summarize the recent progress of RNA aptamers as potential therapeutics, and highlight a few pioneer examples in the stage of both clinical trials and pre-clinical developments.

Comparative analyses of histone H3K9 trimethylations in the heart and spleen of normal humans

The global features of trimethylations of histone 3 at lysine 9 (H3K9me3) have been well studied in recent years; however, most of these studies were performed in mammalian cell lines. In this study, we generated genome-wide maps of H3K9me3 of the human heart and spleen using chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) technology. We examined the global patterns of H3K9me3 in both tissues and found that modifications were closely associated with tissue-specific expression, function, and development. In addition, we found that 169 genes displayed significant H3K9me3 differences between the heart and spleen. Among these genes, 64 were heart-H3K9me3-specific, 87 genes were spleen-H3K9me3-specific, and 18 were shared in both heart- and spleen-H3K9me3. In conclusion, we observed significant differences in H3K9me3 in the heart and spleen, which may help to explain epigenetic differences between these tissues. Such novel findings highlight the significance of H3K9me3 as a potential biomarker or promising target for epigenetic-based disease treatment.

Diagnostic performance of micropthalmia transcription factor for melanoma: a systematic review and meta-analysis

BACKGROUND AND AIM

The diagnosis of melanoma is still a clinical challenge, many studies reported that micropthalmia transcription factor (MITF) plays a role in diagnosing melanoma, but with considerable inconsistent results. The present work aimed to summarize the overall performance of MITF in diagnosing melanoma.

METHODS

A systematic literature search was performed in Pubmed and Embase for studies regarding the usefulness of MITF to diagnose melanoma. Data were retrieved and pooled sensitivity, specificity, positive and negative likelihood ratios, and diagnostic odds ratio were determined. The post-test probability was performed to evaluate clinical usefulness. A summary receiver operator characteristic curve and the area under the curve were used to summarize the overall diagnostic accuracy.

RESULTS

Nine studies with 1,299 subjects (651 melanomas and 648 non-melanomas) were included for present meta-analysis. The pooled sensitivity and specificity of MITF for diagnosing melanoma were 0.84 (95% CI: 0.81-0.87) and 0.96 (95% CI: 0.95-0.98), respectively. The positive likelihood ratio was 17.73 (95% CI: 10.85-28.99), negative likelihood ratio was 0.18 (95% CI: 0.10-0.32) and diagnostic odds ratio was 221.56 (95% CI: 66.16-741.96). In a setting of 20% prevalence of melanoma, the probability of melanoma would be 92% if the MITF test was positive, and the probability of melanoma would be 1% if it was negative. The area under the summary receiver operator characteristic curve was 0.99.

CONCLUSIONS

MITF may play a valuable role in the diagnosis of melanoma with a high specificity. Nevertheless, the results of MITF should be interpreted with the combination of other test results and clinical findings.

The +252A/G polymorphism in the Lymphotoxin-α gene and the risk of non-Hodgkin lymphoma: a meta-analysis

BACKGROUND AND OBJECTIVES

Many studies have shown that the +252A/G polymorphism in the lymphotoxin-α gene is implicated in susceptibility to non-Hodgkin lymphoma but with considerable variance of results. This study aimed to clarify the overall association between the +252A/G polymorphism in the lymphotoxin-α gene and non-Hodgkin lymphoma (NHL) risk by performing a meta-analysis.

MATERIALS AND METHODS

The Pubmed and Embase databases were searched for all studies relating to lymphotoxin-α +252A/G gene polymorphism and NHL risk. Data were retrieved and statistical analyses were performed using the Revman 5.1 and STATA 12.0 software.

RESULTS

Fourteen case-control studies with 25,098 subjects were included. There was no significant association between lymphotoxin-α +252A/G gene polymorphism and the risk of NHL in the all-combined analysis (OR = 1.08, 95%CI: 0.98-1.19 for GG+GA vs. AA; OR = 1.05, 95%CI: 0.95-1.25 for GG vs. GA+AA). In a subgroup analysis by ethnicity, increased NHL risk was found in North Americans (OR = 1.21, 95%CI: 1.05-1.39 for GG+GA vs. AA), no significant association with NHL risk was identified in Asians or Europeans; In a subgroup analysis by NHL subtype, a significantly increased risk was identified in diffuse large B cell lymphoma patients (OR = 1.20 95%CI: 1.11-1.29 for GG+GA vs. AA), but not for follicular lymphoma.

CONCLUSIONS

This meta-analysis suggested that the lymphotoxin-α +252A/G gene polymorphism is a risk factor for NHL in North Americans, and this polymorphism may contribute to diffuse large B cell lymphoma susceptibility. Future studies that include different types of NHL and ethnicities are needed to support and extend these observations.

As an independent prognostic factor, FAT10 promotes hepatitis B virus-related hepatocellular carcinoma progression via Akt/GSK3β pathway

FAT10 is an oncogene that is localized at 6q21.3, a region frequently amplified in hepatocellular carcinoma (HCC). Recently, growing attention has been paid to its effect in the initiation of various cancers. However, there has been little research into the influence of FAT10 on the progression and prognosis of HCC, especially in hepatitis B virus (HBV)-related HCC. Here, we aimed at investigating clincopathological significance of FAT10 in HBV-related HCC and its underlying mechanisms. Based on the analysis of FAT10 expression in a reliable and large number of cases with 5-year follow-up, we showed that FAT10 was significantly increased in 260 samples from HBV-related HCC patients, compared with 30 normal tissue, 50 cirrhosis and matched adjacent nontumor tissues. FAT10 expression is correlated with recurrence and poor prognosis in HBV-related HCC. In addition, ectopic expression of FAT10 enhanced cell proliferation, inhibited apoptosis and induced cell cycle progression, whereas silencing FAT10 expression suppressed cell proliferation and induced apoptosis. FAT10 also induced the epithelial-mesenchymal transition (EMT) and promoted invasion of HCC cells. Furthermore, we found Akt/GSK3β pathway contributed to the effects of FAT10 in HCC cells. Blocking the Akt pathway significantly inhibited the actions of FAT10. Taken together, the ubiquitin-like protein FAT10 has a central role in regulating diverse aspects of the pathogenesis of HCC, indicating that it might be a potential therapeutic target.

Antihypertensive efficacy of the angiotensin receptor blocker azilsartan medoxomil compared with the angiotensin-converting enzyme inhibitor ramipril

Drug therapy often fails to control hypertension. Azilsartan medoxomil (AZL-M) is a newly developed angiotensin II receptor blocker with high efficacy and good tolerability. This double-blind, controlled, randomised trial compared its antihypertensive efficacy and safety vs the angiotensin-converting enzyme inhibitor ramipril (RAM) in patients with clinic systolic blood pressure (SBP) 150-180 mm Hg. Patients were randomised (n=884) to 20 mg AZL-M or 2.5 mg RAM once daily for 2 weeks, then force-titrated to 40 or 80 mg AZL-M or 10 mg RAM for 22 weeks. The primary endpoint was change in trough, seated, clinic SBP. Mean patient age was 57±11 years, 52.4% were male, 99.5% were Caucasian. Mean baseline BP was 161.1±7.9/94.9±9.0 mm Hg. Clinic SBP decreased by 20.6±0.95 and 21.2±0.95 mm Hg with AZL-M 40 and 80 mg vs12.2±0.95 mm Hg with RAM (P<0.001 for both AZL-M doses). Adverse events leading to discontinuation were less frequent with AZL-M 40 and 80 mg (2.4% and 3.1%, respectively) than with RAM (4.8%). These data demonstrated that treatment of stage 1-2 hypertension with AZL-M was more effective than RAM and better tolerated.

Receptors, endocytosis, and trafficking: the biological basis of targeted delivery of antisense and siRNA oligonucleotides

The problem of targeted delivery of antisense and siRNA oligonucleotides can be resolved into two distinct aspects. The first concerns devising ligand-oligonucleotide or ligand-carrier moieties that bind with high selectivity to receptors on the cell type of interest and that are efficiently internalized by endocytosis. The second concerns releasing oligonucleotides from pharmacologically inert endomembrane compartments so that they can access RNA in the cytosol or nucleus. In this review, we will address both of these aspects. Thus, we present information on three important receptor families, the integrins, the receptor tyrosine kinases, and the G protein-coupled receptors in terms of their suitability for targeted delivery of oligonucleotides. This includes discussion of receptor abundance, internalization and trafficking pathways, and the availability of suitable high affinity ligands. We also consider the process of oligonucleotide uptake and intracellular trafficking and discuss approaches to modulating these processes in a pharmacologically productive manner. Hopefully, the basic information presented in this review will be of value to investigators involved in designing delivery approaches for oligonucleotides.

Hypertonic saline reduces lipopolysaccharide-induced mouse brain edema through inhibiting aquaporin 4 expression

INTRODUCTION

Three percent sodium chloride (NaCl) treatment has been shown to reduce brain edema and inhibited brain aquaporin 4 (AQP4) expression in bacterial meningitis induced by Escherichia coli. Lipopolysaccharide (LPS) is the main pathogenic component of E. coli. We aimed to explore the effect of 3% NaCl in mouse brain edema induced by LPS, as well as to elucidate the potential mechanisms of action.

METHODS

Three percent NaCl was used to treat cerebral edema induced by LPS in mice in vivo. Brain water content, IL-1β, TNFα, immunoglobulin G (IgG), AQP4 mRNA and protein were measured in brain tissues. IL-1β, 3% NaCl and calphostin C (a specific inhibitor of protein kinase C) were used to treat the primary astrocytes in vitro. AQP4 mRNA and protein were measured in astrocytes. Differences in various groups were determined by one-way analysis of variance.

RESULTS

Three percent NaCl attenuated the increase of brain water content, IL-1β, TNFα, IgG, AQP4 mRNA and protein in brain tissues induced by LPS. Three percent NaCl inhibited the increase of AQP4 mRNA and protein in astrocytes induced by IL-1β in vitro. Calphostin C blocked the decrease of AQP4 mRNA and protein in astrocytes induced by 3% NaCl in vitro.

CONCLUSIONS

Osmotherapy with 3% NaCl ameliorated LPS-induced cerebral edema in vivo. In addition to its osmotic force, 3% NaCl exerted anti-edema effects possibly through down-regulating the expression of proinflammatory cytokines (IL-1β and TNFα) and inhibiting the expression of AQP4 induced by proinflammatory cytokines. Three percent NaCl attenuated the expression of AQP4 through activation of protein kinase C in astrocytes.