High-dose pulse methylprednisolone vs. dexamethasone standard therapy for severe and critical COVID-19 pneumonia: Efficacy assessment in a retrospective single-centre experience from Malaysia

INTRODUCTION

The use of dexamethasone (DXM) has been associated with decreased mortality in the patients with hypoxemia during the coronavirus disease-2019 (COVID-19) pandemic, while the outcomes with methylprednisolone (MTP) have been mixed. This real-life study aimed to evaluate the outcomes of patients with severe respiratory failure due to COVID-19 who were treated with high doses of MTP.

MATERIALS AND METHODS

This retrospective cohort study enrolled hospitalised patients between May 2021 and August 2021, aged 18 years and above, with severe respiratory failure defined by a ratio of oxygen saturation to fraction of inspired oxygen (SF ratio) of less than 235. The treatment protocol involved administering high-dose MTP for 3 days, followed by DXM, and the outcomes were compared with those of patients who received DXM alone (total treatment duration of 10 days for both groups).

RESULTS

A total of 99 patients were enrolled, with 79 (79.8%) receiving pulse MTP therapy and 20 (20.2%) being treated with DXM only. The SF ratio significantly improved from a mean of 144.49 (±45.16) at baseline to 208 (±85.19) at 72 hours (p < 0.05), with a mean difference of 63.51 (p < 0.001) in patients who received ≤750 mg of MTP. Additionally, in patients who received >750 mg of MTP, the SF ratio improved from a baseline mean of 130.39 (±34.53) to 208.44 (±86.61) at 72 hours (p < 0.05), with a mean difference of 78.05 (p = 0.001). In contrast, patients who received DXM only demonstrated an SF ratio of 132.85 (±44.1) at baseline, which changed minimally to 133.35 (±44.4) at 72 hours (p = 0.33), with a mean difference of 0.50 (p = 0.972). The incidence of nosocomial infection was higher in the MTP group compared with the DXM group (40.5% vs. 35%, p = 0.653), with a relative risk of 1.16 (95% CI: 0.60-2.23).

CONCLUSION

MTP did not demonstrate a significant reduction in intubation or intensive care unit admissions. Although a high dose of MTP improved gas exchange in patients with severe and critical COVID-19, it did not provide an overall mortality benefit compared to standard treatment.

Dynamic metastable polymersomes enable continuous flow manufacturing

Polymersomes are polymeric analogues of liposomes with exceptional physical and chemical properties. Despite being dubbed as next-generation vesicles since their inception nearly three decades ago, polymersomes have yet to experience translation into the clinical or industrial settings. This is due to a lack of reliable methods to upscale production without compromising control over polymersome properties. Herein we report a continuous flow methodology capable of producing near-monodisperse polymersomes at scale (≥3 g/h) with the possibility of performing downstream polymersome manipulation. Unlike conventional polymersomes, our polymersomes exhibit metastability under ambient conditions, persisting for a lifetime of ca. 7 days, during which polymersome growth occurs until a dynamic equilibrium state is reached. We demonstrate how this metastable state is key to the implementation of downstream processes to manipulate polymersome size and/or shape in the same continuous stream. The methodology operates in a plug-and-play fashion and is applicable to various block copolymers.

Mixtures of acid- and base-functionalized microparticles for one-pot cascade reaction

We report on the synthesis of surface-protected acid and base microparticles via surfactant-free emulsion polymerization. The protective layer allows to form particle mixtures with both colloidal catalysts that show excellent performance in a well-established model cascade reaction involving an acid-catalyzed deacetalization and a subsequent base-catalyzed Knoevenagel condensation. Compared to nanoreactors that contain both catalysts, the colloidal mixture shows comparable reaction kinetics despite the local separation of both catalysts onto separate particles. Since the synthesis of individual microparticles requires less steps, is scalable, and more versatile in terms of catalyst variation, colloidal mixtures are certainly an alternative to multifunctional nanoreactors, making them attractive for practical applications. This article is protected by copyright. All rights reserved.

Macrophage-Targeting and Complete Lysosomal Degradation of Self-assembled Two-Dimensional Poly(ε-caprolactone) Platelet Particles

Understanding cellular uptake and particle trafficking within the cells is essential for targeted drug delivery applications. Existing studies reveal that the geometrical aspects of nanocarriers, for example, shape and size, determine their cell uptake and sub-cellular transport pathways. However, considerable efforts have been directed toward understanding the cell uptake mechanism and trafficking of spherical particles. Detailed analysis on the uptake mechanism and downstream intracellular processing of non-spherical particles remains elusive. Here, we used polymeric two-dimensional platelets based on poly(ε-caprolactone) (PCL) prepared by living crystallization-driven self-assembly as a platform to investigate the cell uptake and intracellular transport of non-spherical particles in vitro. PCL is known to degrade only slowly, and these platelets were still stable after 2 days of incubation in artificial lysosomal media. Upon cell uptake, the platelets were transported through an endo/lysosomal pathway and were found to degrade completely in the lysosome at the end of the cell uptake cycle. We observed a morphological transformation of the lysosomes, which correlates with the stages of platelet degradation in the lysosome. Overall, we found an accelerated degradation of PCL, which was likely caused by mechanical forces inside the highly stretched endosomes.

Host inflammatory response is the major marker of severe respiratory syncytial virus infection in older adults

OBJECTIVES

We aim to study the viral kinetics and host inflammatory response of RSV infection in older adults, and their correlation with disease severity.

METHODS

We performed a prospective observational study in adults with RSV infection. We serially collected nasal-throat swabs for quantification of RSV-A and RSV-B viral load, and peripheral blood samples for measurement of cytokine/chemokine concentrations. The study endpoints were (i) requiring supplemental oxygen therapy, and (ii) non-invasive ventilation, intensive care, or died within 30 days of admission. We performed multivariable logistic regression models to identify independent variables for severe disease.

RESULTS

We enrolled 71 hospitalized patients and 10 outpatients treated for RSV infection (median age 75 years, 51% male, and 74% with comorbidities). Among hospitalized patients, 61% required supplemental oxygen therapy, and 18% had severe disease requiring non-invasive ventilation or intensive care, or died within 30 days. Inflammatory cytokine/chemokines IL-6, CXCL8/IL-8, CXCL9/MIG and CXCL10/IP-10 increased significantly during the acute phase of illness. IL-6 concentration was independently associated with severe disease after adjusting for confounding factors. RSV viral load was not associated with disease severity throughout the course of illness.

CONCLUSION

Host inflammatory response is a major marker of severe disease in older adults with RSV infection.

Size-Controlled Formation of Polymer Janus Discs

A straightforward method is presented for the preparation of nano- to micrometer-sized Janus discs with controlled shape, size, and aspect ratio. The method relies on cross-linkable ABC triblock terpolymers and involves first the preparation of prolate ellipsoidal microparticles by combining Shirasu porous glass (SPG) membrane emulsification with evaporation-induced confinement assembly (EICA). By varying the pore diameter of the SPG membrane, we produce Janus discs with controlled size distributions centered around hundreds of nanometers to several microns. We further transferred the discs to water by mild sulfonation of PS to polystyrene sulfonic acid (PSS) and verified the Janus character by subsequent labelling with cationic nanoparticles. Finally, we show that the sulfonated Janus discs are amphiphilic and can be used as efficient colloidal stabilizers for oil-in-water (O/W) emulsions.

Scalable and Recyclable All-Organic Colloidal Cascade Catalysts

We report on the synthesis of core–shell microparticles (CSMs) with an acid catalyst in the core and a base catalyst in the shell by surfactant‐free emulsion polymerization (SFEP). The organocatalytic monomers were separately copolymerized in three synthetic steps allowing the spatial separation of incompatible acid and base catalysts within the CSMs. Importantly, a protected and thermo‐decomposable sulfonate monomer was used as acid source to circumvent the neutralization of the base catalyst during shell formation, which was key to obtain stable, catalytically active CSMs. The catalysts showed excellent performance in an established one‐pot model cascade reaction in various solvents (including water), which involved an acid‐catalyzed deacetalization followed by a base‐catalyzed Knoevenagel condensation. The CSMs are easily recycled, modified, and their synthesis is scalable, making them promising candidates for organocatalytic applications.

Modulating the Selectivity and Stealth Properties of Ellipsoidal Polymersomes through a Multivalent Peptide Ligand Display

There is a need for improved nanomaterials to simultaneously target cancer cells and avoid non-specific clearance by phagocytes. An ellipsoidal polymersome system is developed with a unique tunable size and shape property. These particles are functionalized with in-house phage-display cell-targeting peptide to target a medulloblastoma cell line in vitro. Particle association with medulloblastoma cells is modulated by tuning the peptide ligand density on the particles. These polymersomes has low levels of association with primary human blood phagocytes. The stealth properties of the polymersomes are further improved by including the peptide targeting moiety, an effect that is likely driven by the peptide protecting the particles from binding blood plasma proteins. Overall, this ellipsoidal polymersome system provides a promising platform to explore tumor cell targeting in vivo.

pH-Controlled Hierarchical Assembly/Disassembly of Multicompartment Micelles in Water

Multicompartment micelles (MCMs) have become attractive drug delivery systems as they allow the separate storage of two or more incompatible cargos in their core compartments (e.g., drugs and dyes for imaging). A recent hierarchical self-assembly process for hydrophobic terpolymers in organic solvents showed the ability to form very homogeneous MCM populations, yet the transfer of this process into water requires a better understanding of the formation mechanism and influence of chain mobility during assembly. Here, the synthesis of a linear poly(oligo(ethylene glycol) methacrylate)-block-poly(benzyl acrylate)-block-poly(4-vinylpyridine) (POEGMA-b-PBzA-b-P4VP) triblock terpolymer by reversible addition-fragmentation chain transfer (RAFT) polymerization is reported as well as its step-wise assembly into MCMs in water with POEGMA corona, PBzA patches, and P4VP core. Reversible assembly/disassembly of the MCMs is investigated through protonation/deprotonation of the P4VP core. Interestingly, the low glass transition temperature (T_g ) of the hydrophobic PBzA middle block causes MCMs to directly disassemble into molecularly dissolved chains instead of patchy micelles due to mechanical stress from electrosteric repulsion of the protonated P4VP corona chains. In addition, pH resistant MCMs are created by core-crosslinking and fluorescent properties are added by covalent anchoring of fluorescent dyes via straightforward click chemistry.

Direct Observation of Topological Defects in Striped Block Copolymer Discs and Polymersomes

Topology and defects are of fundamental importance for ordered structures on all length scales. Despite extensive research on block copolymer self-assembly in solution, knowledge about topological defects and their effect on nanostructure formation has remained limited. Here, we report on the self-assembly of block copolymer discs and polymersomes with a cylinder line pattern on the surface that develops specific combinations of topological defects to satisfy the Euler characteristics for closed spheres as described by Gauss-Bonnet theorem. The dimension of the line pattern allows the direct visualization of defect emergence, evolution, and annihilation. On discs, cylinders either form end-caps that coincide with λ^+1/2 disclinations or they bend around τ^+1/2 disclinations in 180° turns (hairpin loops). On polymersomes, two λ^+1/2 defects connect into three-dimensional (3D) Archimedean spirals, while two τ^+1/2 defects form 3D Fermat spirals. Electron tomography reveals two complementary line patterns on the inside and outside of the polymersome membrane, where λ^+1/2 and τ^+1/2 disclinations always eclipse on opposing sides ("defect communication"). Attractive defects are able to annihilate with each other into +1 disclinations and stabilize anisotropic polymersomes with sharp tips through screening of high-energy curvature. This study fosters our understanding of the behavior of topological defects in self-assembled polymer materials and aids in the design of polymersomes with preprogrammed shapes governed by synthetic block length and topological rules.

A case of co-infection: First reported case of severe plasmodium knowlesi malaria and dengue co-infection in Sabah, Malaysia

We report a rare case of severe Plasmodium knowlesi malaria and dengue co-infection in a 36-year-old lady with hyperparasitaemia, metabolic acidosis, haemolysis and acute kidney injury. She was in shock requiring inotropic support and elective intubation. She had pericardial tamponade which necessitate pericardiocentesis to allow for haemodynamic stability during haemodialysis. She underwent haemodialysis, was ventilated for six days and stayed in hospital for 29 days. She was discharged home well with almost complete renal recovery. Physicians must have a high degree of suspicion for dengue co-infection in malaria patients with plasma leakage such as pericardial effusion to allow for prompt management.

Surface roughness influences the protein corona formation of glycosylated nanoparticles and alter their cellular uptake

Recently the role of protein absorption in nanoparticle drug delivery has gathered significant attention as the protein corona can significantly decide on the fate of nanoparticles in the body. Although it is known that the surface chemistry will significantly influence the amount and type of bound protein, there is little known about the effect of surface roughness and surface topography on the interaction. In this work, we show how patchy nanoparticles can noticeably reduce the adsorption of proteins compared to spherical nanoparticles with a smooth surface as demonstrated using six ABC triblock terpolymers based on glucose, mannose and galactose. To obtain patchy nanoparticles, poly(2-d-sugar ethyl acrylate)-b-poly (n-butyl acrylate)-b-poly(4-vinyl pyridine) (PSugEA-b-PBuA-b-P4VP) was prepared by reversible addition-fragmentation chain-transfer (RAFT) polymerization and assembled into nanoparticles with a patch-like appearance and a hydrodynamic diameter of around 130-160 nm. As control, smooth nanoparticles were prepared from poly(2-d-sugar ethyl acrylate)-b-poly (n-butyl acrylate)-b-polystyrene (PSugEA-b-PBuA-b-PS). The patchy nanoparticles displayed significantly reduced protein absorption when exposed to serum-supplemented cell culture media, as observed using dynamic light scattering. The smooth particles, however, supported the formation of a large protein corona. Additionally, an enrichment of haemoglobin was observed in the corona compared to the serum protein in solution. The amount of albumin on the surface was observed to be dependent on the type of sugar with glucose resulting in the highest absorption. The protein corona led to cellular uptake that was unrelated to the underlying sugar, which was supposed to help targeting specific cell lines. This example demonstrated how the protein corona can override any attempts to target receptor expressing cells.

Bioactive Patchy Nanoparticles with Compartmentalized Cargoes for Simultaneous and Trackable Delivery

Recent years have seen an increased interest in the use of ABC triblock terpolymers to bottom-up assemble multicompartment patchy nanoparticles. Despite these experimental and theoretical efforts, the applications of polymer-based patchy nanoparticles remain rather limited. One of the major challenges that eclipses their potential is the lack of knowledge to selectively encapsulate cargoes within different compartments that are separated in the nanometer length scale. Here, strategies are reported to segregate two chemically distinct molecules in either the patches or core compartment of patchy nanoparticles that bear a (bioactive) sugar corona. The potential use of these bioactive patchy nanoparticles containing compartmentalized cargoes for simultaneous drug delivery with real-time release monitoring capabilities is further demonstrated.

Faceted polymersomes: a sphere-to-polyhedron shape transformation

The creation of "soft" deformable hollow polymeric nanoparticles with complex non-spherical shapes via block copolymer self-assembly remains a challenge. In this work, we show that a perylene-bearing block copolymer can self-assemble into polymeric membrane sacs (polymersomes) that not only possess uncommonly faceted polyhedral shapes but are also intrinsically fluorescent. Here, we further reveal for the first time an experimental visualization of the entire polymersome faceting process. We uncover how our polymersomes facet through a sphere-to-polyhedron shape transformation pathway that is driven by perylene aggregation confined within a topologically spherical polymersome shell. Finally, we illustrate the importance in understanding this shape transformation process by demonstrating our ability to controllably isolate different intermediate polymersome morphologies. The findings presented herein should provide opportunities for those who utilize non-spherical polymersomes for drug delivery, nanoreactor or templating applications, and those who are interested in the fundamental aspects of polymersome self-assembly.

Just add sugar for carbohydrate induced self-assembly of curcumin

In nature, self-assembly processes based on amphiphilic molecules play an integral part in the design of structures of higher order such as cells. Among them, amphiphilic glycoproteins or glycolipids take on a pivotal role due to their bioactivity. Here we show that sugars, in particular, fructose, are capable of directing the self-assembly of highly insoluble curcumin resulting in the formation of well-defined capsules based on non-covalent forces. Simply by mixing an aqueous solution of fructose and curcumin in an open vessel leads to the generation of capsules with sizes ranging between 100 and 150 nm independent of the initial concentrations used. Our results demonstrate that hydrogen bonding displayed by fructose can induce the self-assembly of hydrophobic molecules such as curcumin into well-ordered structures, and serving as a simple and virtually instantaneous way of making nanoparticles from curcumin in water with the potential for template polymerization and nanocarriers.

Non-spherical polymersomes: formation and characterization

This tutorial review summarizes recent efforts over the past decade to study the morphological transformation of conventionally spherical polymersomes into non-spherical polymersomes.

Evaluation of three rapid oral fluid test devices on the screening of multiple drugs of abuse including ketamine

Rapid oral fluid testing (ROFT) devices have been extensively evaluated for their ability to detect common drugs of abuse; however, the performance of such devices on simultaneous screening for ketamine has been scarcely investigated. The present study evaluated three ROFT devices (DrugWipe^® 6S, Ora-Check^® and SalivaScreen^®) on the detection of ketamine, opiates, methamphetamine, cannabis, cocaine and MDMA. A liquid chromatography tandem mass spectrometry (LCMS) assay was firstly established and validated for confirmation analysis of the six types of drugs and/or their metabolites. In the field test, the three ROFT devices were tested on subjects recruited from substance abuse clinics/rehabilitation centre. Oral fluid was also collected using Quantisal^® for confirmation analysis. A total of 549 samples were collected in the study. LCMS analysis on 491 samples revealed the following drugs: codeine (55%), morphine (49%), heroin (40%), methamphetamine (35%), THC (8%), ketamine (4%) and cocaine (2%). No MDMA-positive cases were observed. Results showed that the overall specificity and accuracy were satisfactory and met the DRUID standard of >80% for all 3 devices. Ora-Check^® had poor sensitivities (ketamine 36%, methamphetamine 63%, opiates 53%, cocaine 60%, THC 0%). DrugWipe^® 6S showed good sensitivities in the methamphetamine (83%) and opiates (93%) tests but performed relatively poorly for ketamine (41%), cocaine (43%) and THC (22%). SalivaScreen^® also demonstrated good sensitivities in the methamphetamine (83%) and opiates (100%) tests, and had the highest sensitivity for ketamine (76%) and cocaine (71%); however, it failed to detect any of the 28 THC-positive cases. The test completion rate (proportion of tests completed with quality control passed) were: 52% (Ora-Check^®), 78% (SalivaScreen^®) and 99% (DrugWipe^® 6S).

Formation of non-spherical polymersomes driven by hydrophobic directional aromatic perylene interactions

Polymersomes, made up of amphiphilic block copolymers, are emerging as a powerful tool in drug delivery and synthetic biology due to their high stability, chemical versatility, and surface modifiability. The full potential of polymersomes, however, has been hindered by a lack of versatile methods for shape control. Here we show that a range of non-spherical polymersome morphologies with anisotropic membranes can be obtained by exploiting hydrophobic directional aromatic interactions between perylene polymer units within the membrane structure. By controlling the extent of solvation/desolvation of the aromatic side chains through changes in solvent quality, we demonstrate facile access to polymersomes that are either ellipsoidal or tubular-shaped. Our results indicate that perylene aromatic interactions have a great potential in the design of non-spherical polymersomes and other structurally complex self-assembled polymer structures.

Remission of systemic lupus erythematosus disease activity with regulatory cytokine interleukin (IL)-35 in Murphy Roths Large (MRL)/lpr mice

The immunological mechanisms mediated by regulatory cytokine interleukin (IL)-35 are unclear in systemic lupus erythematosus (SLE). We investigated the frequency of CD4(+) CD25(+) forkhead box protein 3 (FoxP3)(+) regulatory T (Treg ) and IL-10(+) regulatory B (Breg ) cells and related immunoregulatory mechanisms in a female Murphy Roths Large (MRL)/lpr mouse model of spontaneous lupus-like disease, with or without IL-35 treatment. A remission of histopathology characteristics of lupus flare and nephritis was observed in the MRL/lpr mice upon IL-35 treatment. Accordingly, IL-35 and IL-35 receptor subunits (gp130 and IL-12Rβ2) and cytokines of MRL/lpr and BALB/c mice (normal controls) were measured. The increased anti-inflammatory cytokines and decreased proinflammatory cytokines were possibly associated with the restoration of Treg and Breg frequency in MRL/lpr mice with IL-35 treatment, compared to phosphate-buffered saline (PBS) treatment. mRNA expressions of Treg -related FoxP3, IL-35 subunit (p35 and EBI3) and soluble IL-35 receptor subunit (gp130 and IL12Rβ2) in splenic cells were up-regulated significantly in IL-35-treated mice. Compared with the PBS treatment group, IL-35-treated MRL/lpr mice showed an up-regulation of Treg -related genes and the activation of IL-35-related intracellular Janus kinase/signal transducer and activator of transcription signal pathways, thereby indicating the immunoregulatory role of IL-35 in SLE. These in vivo findings may provide a biochemical basis for further investigation of the regulatory mechanisms of IL-35 for the treatment of autoimmune-mediated inflammation.

Aberrant expression of regulatory cytokine IL-35 in patients with systemic lupus erythematosus

Objective

This study characterizes an IL-35-mediated regulatory role in patients with systemic lupus erythematosus (SLE).

Methods

Plasma of SLE patients and healthy controls (HCs) was analyzed for the concentrations of IL-35 and soluble gp130 by using ELISA. mRNA expression of IL-35 subunit (p35 and EBI3) and its receptor (gp130 and IL-12Rβ2) in peripheral blood mononuclear cells (PBMCs) was assessed by RT-qPCR. Flow cytometry was performed to evaluate the number of CD4+CD25highCD127−Treg cells and the expression of IL-35 receptor on the CD4+ helper (Th) cells and CD19+ B cells. Plasma collected from SLE patients and HCs was assayed for cytokine and chemokine expression by Luminex multiplex assay.

Results

Plasma IL-35 and soluble gp130 levels positively correlated with each other and were significantly higher in patients with severe SLE compared with HCs. Significantly higher levels of inflammatory cytokines/chemokines CCL2, CXCL8, IL-6, interferon (IFN)-γ, IL-10 and IL-17A were observed in plasma of SLE patients than HCs. mRNA levels of IL-35 and its receptor were significantly positively correlated in PBMCs from SLE patients and their levels were higher in SLE than HCs. The increase significantly correlated with changes in SLE Disease Activity Index (SLEDAI) (all p < 0.05). In addition, the number of Treg cells in severe and moderate SLE patients were both significantly lower than HCs, where the ratio of CD4+CD25−effector T cell %/CD4+CD25highCD127−Treg % was found to be significantly higher in severe SLE patients. Furthermore, the expression of gp130 on CD4+ Th cells and percentage of Tregs were positively correlated with each other, and both were negatively correlated with SLEDAI.

Conclusion

Our findings indicate that high level of plasma IL-35 in active SLE patients expressed with low level of IL-35 receptor (gp130) on CD4+ Th cells. These data raise the possibility that the level of IL-35 expression in SLE patients is not sufficient to induce the production of CD4+CD25highCD127−Tregs, and subsequently suppress the release of inflammatory cytokines and chemokines upon inflammation.

An Oligonucleotide Transfection Vector Based on HSA and PDMAEMA Conjugation: Effect of Polymer Molecular Weight on Cell Proliferation and on Multicellular Tumor Spheroids

A novel gene transfection vector was fabricated based on the conjugation of human serum albumin (HSA) and maleimide end functionalized poly[(N,N-dimethylamino) ethyl methacrylate] (PDMAEMA). The bioconjugation was achieved in a site-specific manner to yield well-defined polymer-protein conjugates. The biohybrid was able to bind DNA with high affinity resulting in nanoparticles with a HSA shell. This paper mainly focuses on the influence of polymeric chain length on the particle properties and their drug-carrying ability to deliver oligonucleotides into breast cancer cells. The cytotoxic agent of interest, ISIS5132, is an oligonucleotide which disrupts DNA function within the cell. There was no evidence that the polymeric chain length had any effects on the conjugation efficiency and the subsequent condensation ability of the conjugates to oligonucleotide. However, the polymeric chain length had an obvious effect on the size of the complex micelles. Low molecular weights only led to loosely compacted complexes with the oligonucleotide, while large molecular weight led to well-defined nanoparticle structures. More importantly, it was found that the variation in the length of the PDMAEMA block resulted in a change in cytotoxicity of the drug loaded complex micelle. That is, the concentration of 50% inhibition (IC50 ) of the complex micelle on MDA-MB-231 and MCF-7 cells reached the lowest value at a chain length of around 21 000 g mol(-1) . The IC50 value increased when the polymeric chain length was shorter (8000 g mol(-1) and 10 000 g mol(-1) ) while it increased again when PDMAMEA of M¯n = 47 000 g mol(-1) , probably due to insufficient release of the drug. These result were reflected when investigating the performance of the polyplex using MCF-7 multicellular tumor spheroids, where again the medium PDMAEMA chain length led to the best delivery vehicle for ISIS5132.

Polymersomes prepared from thermoresponsive fluorescent protein-polymer bioconjugates: capture of and report on drug and protein payloads

Polymersomes provide a good platform for targeted drug delivery and the creation of complex (bio)catalytically active systems for research in synthetic biology. To realize these applications requires both spatial control over the encapsulation components in these polymersomes and a means to report where the components are in the polymersomes. To address these twin challenges, we synthesized the protein-polymer bioconjugate PNIPAM-b-amilFP497 composed of thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) and a green-fluorescent protein variant (amilFP497). Above 37 °C, this bioconjugate forms polymersomes that can (co-)encapsulate the fluorescent drug doxorubicin and the fluorescent light-harvesting protein phycoerythrin 545 (PE545). Using fluorescence lifetime imaging microscopy and Förster resonance energy transfer (FLIM-FRET), we can distinguish the co-encapsulated PE545 protein inside the polymersome membrane while doxorubicin is found both in the polymersome core and membrane.

Members of the receptor for advanced glycation end products axis as potential therapeutic targets in patients with lupus nephritis

The relationship of inflammation and the expression of full-length receptor for advanced glycation end products (flRAGE) on monocytes, plasma levels of RAGE ligand high mobility group box protein 1 (HMGB1), soluble RAGE (sRAGE) and endogenous secretory RAGE (esRAGE) was assessed to elucidate the effect of HMGB1/DNA/RAGE-mediated innate inflammatory responses in patients with lupus nephritis. Cell surface expression of flRAGE was elevated on the monocytes of lupus patients, correlated with plasma HMGB1 levels. Plasma sRAGE level negatively correlated with systemic lupus erythematosus (SLE) disease activity index. Plasma esRAGE level was significantly lower in SLE patients with flare while esRAGE/sRAGE ratio negatively correlated with complement C3 level. HMGB1 alone could moderately induce ex vivo IL-6 production from monocytes, resulting in activation of intracellular p38 mitogen-activated protein kinase (MAPK), c-Jun N-terminal kinase and nuclear factor (NF)-κB. Moreover, toll-like receptor-9 ligand together with HMGB1 exhibited a synergistic effect on IL-6 and IL-12p70 secretions and the phosphorylation of p38 MAPK and NF-κB. Therefore, over-expression of flRAGE in lupus may lead to the amplification of RAGE ligands-mediated inflammatory responses through the activation of p38 MAPK and NF-κB. Plasma sRAGE may serve as a potential biomarker for disease activity and a future therapeutic target in SLE.

Polymer-induced change in scaling behavior in two-dimensional homogeneous turbulent thermal convection

We study the effects of polymers in two-dimensional turbulent thermal convection using a shell model. In the absence of polymers, the inverse energy cascade in two dimensions leads to the observed Bolgiano-Obukhov scaling. When polymers are added, energy is extracted from the flow by the polymers, and as a result, the thermal balance between buoyancy and inertia in Bolgiano-Obukhov scaling is destroyed around the scales at which polymers interact strongly with the flow. This results in an increase in the Bolgiano scale and leads to a change in the scaling behavior of the velocity and temperature fluctuations for scales below the modified Bolgiano scale. We make theoretical estimates of the dependence of the mean rate of energy extracted by the polymers and the mean energy dissipation rate on the polymer relaxation time. Our theoretical analysis further leads to the prediction that the heat transport is not altered much by the polymers in two dimensions. We show that our theoretical estimates and prediction are in good agreement with the numerical results.

Transnasal penetrating intracranial injury with a chopstick

We report the first case of a transnasal penetrating intracranial injury in Hong Kong by a chopstick. A 49-year-old man attempted suicide by inserting a wooden chopstick into his left nose and then pulled it out. The chopstick caused a transnasal penetrating brain injury, confirmed by contrast magnetic resonance imaging of the brain. He was managed conservatively. Later he developed meningitis without a brain abscess and was prescribed antibiotics for 6 weeks. He enjoyed a good neurological recovery. This case illustrates that clinician should have a high index of suspicion for penetrating intracranial injury due to a nasally inserted foreign body, even though it had already been removed. In such cases moreover, brain magnetic resonance imaging is the imaging modality of choice, as it can delineate the path of penetration far better than plain computed tomography.

Effect of raloxifene on disease activity and vascular biomarkers in patients with systemic lupus erythematosus: subgroup analysis of a double-blind randomized controlled trial

OBJECTIVES

The purpose of this study was to identify the effect of raloxifene on disease activity and vascular biomarkers in patients with systemic lupus erythematosus (SLE).

METHODS

Subgroup data were analyzed for postmenopausal female SLE patients who participated in a randomized controlled trial of raloxifene on glucocorticoid-induced osteoporosis. Patients who were receiving a stable daily dose of prednisolone (≤10 mg) for ≥6 months were assigned to receive raloxifene (60 mg/day) or placebo on top of calcium and vitamin D. Disease activity was assessed by the Safety of Estrogens in Lupus Erythematosus National Assessment (SELENA), SLE disease activity index (SLEDAI) and physicians' global assessment (PGA) every three months. Lupus flares were assessed by the SELENA flare instrument. Serial serum levels of homocysteine, high-sensitivity C-reactive protein (hsCRP) and soluble thrombomodulin (sTM) were measured.

RESULTS

A total of 62 patients (30 raloxifene, 32 placebo) were studied (age 52.5 ± 6.7 years; SLE duration 9.3 ± 7.6 years; menopause duration 7.2 ± 6.6 years). The SLEDAI at entry was 1.8 ± 2.3 (SLEDAI ≥ 6 in 8%). After 12 months, a significant gain in bone mineral density (BMD) of the lumbar spine (1.6%, p = 0.02), and reduction in bone resorption and formation markers was observed in the raloxifene but not in the placebo treated patients. The SELENA-SLEDAI and PGA scores area under the curve over 12 months were not significantly different between the two groups. There were three episodes of mild/moderate lupus flares (33% musculoskeletal, 33% dermatological) in the raloxifene group, compared to nine episodes of mild/moderate flares (27% musculoskeletal, 45% dermatological) in the placebo group (p = 0.11). The low density lipoprotein (LDL) cholesterol level increased significantly in the placebo but not raloxifene treated patients. No significant changes in homocysteine, hsCRP and sTM levels were observed in either group of patients.

CONCLUSIONS

Raloxifene significantly improves lumbar spine BMD in SLE patients but does not cause an increase in lupus activity or flares.

Muramyl dipeptide mediated activation of human bronchial epithelial cells interacting with basophils: a novel mechanism of airway inflammation

Respiratory tract bacterial infection can amplify and sustain airway inflammation. Intracytosolic nucleotide-binding oligomerization domain-containing protein 2 (NOD2) is one member of the nucleotide binding and oligomerization domain (NOD)-like receptor (NLR) family, which senses the conserved structural peptidoglycan component muramyl dipeptide (MDP) in almost all bacteria. In the present study, activation of the NOD2 ligand MDP on primary human bronchial epithelial cells (HBE) co-cultured with human basophils was investigated. Cytokines, NOD2, adhesion molecules and intracellular signalling molecules were assayed by enzyme-linked immunosorbent assay or flow cytometry. The protein expression of NOD2 was confirmed in basophils/KU812 cells and HBE/human bronchial epithelial cell line (BEAS-2B) cells. MDP was found to up-regulate significantly the cell surface expression of intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1 on basophils and HBE in the co-culture system with or without basophil priming by interleukin (IL)-33 (all P < 0·05). MDP could further enhance the release of inflammatory cytokine IL-6 and chemokine CXCL8, and epithelium-derived anti-microbial peptide β-defensin 2 in the co-culture. HBE cells were the major source for the release of IL-6, CXCL8 and β-defensin2 upon stimulation by MDP in the co-culture system. The expression of ICAM-1 and VCAM-1 and release of IL-6 and CXCL8 were suppressed by various signalling molecule inhibitors, implying that the interaction between basophils and primary human bronchial epithelial cells could be regulated differentially by the mitogen-activated protein kinase pathways and nuclear transcription factors. The results therefore provide a new insight into the functional role of basophils in innate immunity, and the link between respiratory bacteria-mediated innate immunity and subsequent amplification of allergic inflammation in the airway.

Angioplasty and stenting for intracranial atherosclerotic stenosis: position statement of the Hong Kong Society of Interventional and Therapeutic Neuroradiology

As a means of preventing secondary ischaemic stroke, angioplasty and stenting are considered potentially beneficial for patients with severe intracranial atherosclerotic stenosis. However, the role of stenting has been challenged since the publication of the first randomised controlled trial on Stenting versus Aggressive Medical Management for Preventing Recurrent stroke in Intracranial arterial Stenosis (SAMMPRIS). This indicated that aggressive medical management was superior to stenting using Wingspan to prevent recurrent stroke, because stenting has a high peri-procedural stroke and death rate. In this paper, we review the management of intracranial atherosclerosis, revisit the skepticism on stenting, and state our position on the topic in the form of recommendations. These are based on the prevalence of the disease in Hong Kong, the high risk of recurrent stroke despite medical therapy in the presence of haemodynamic intracranial stenosis without sufficient collaterals, an analysis of the weak points of SAMMPRIS, and results of clinical studies in Hong Kong.

An integrated lab-on-a-disc for automated cell-based allergen screening bioassays

We have utilized various valving scheme to leverage purely rotation-regulated flow control to enable comprehensive cell-based bioassays (CBBs) on centrifuge-based lab-on-a-disc (LOAD). A LOAD has been developed to examine allergic degranulation from live basophils for allergens screening for the first time, which can also be adjusted to suit a wide range of CBBs. In this system, controlled allergic reaction together with mediator separation from basophils using siphon valving and centrifugal sedimentation are realized inside microstructured network. The entire degranulation analysis process including on-demand release of samples, reaction and degranulation, allergic mediator separation and detection is executed in an automatic sequence within a single run. To validate our cell-based approach, detection of degranulation mediated by known secretagagues, ionomycin or chemotatic peptide formyl-methionine-leucine-pheylalanine (fMLP), is first demonstrated. Further experiments using real allergens house dust mite protein (Der p1) and its corresponding human serum IgE also show positive results. The overall efficiency of the assay is 80.6%, which is comparable to other conventional methods. With 4 identical units on a disc running in a parallel format, the device offers the possibility of single-step, multiplexed allergens screening. The device is capable of reporting a result within 30 min. It has many desirable merits including fast and multiplexed analysis, low cost, single-step operation, minimal sample volume, less discomfort and most importantly increased safety as patients are no longer susceptible to possible anaphylactic shock reactions induced by the common skin-prick-test. The flexibility of the flow control within the device makes it suitable to a wide range of CBBs.

A narrative review of evidence-based recommendations for the physical examination of the lumbar spine, sacroiliac and hip joint complex

Non-specific low back pain is a frequent complaint in primary care, but the differential diagnosis for low back pain can be complex. Despite advances in diagnostic imaging, a specific pathoanatomical source of low back pain can remain elusive in up to 85% of individuals. Best practice guidelines recommend that clinicians conduct a focused physical examination to help to identify patients with non-specific low back pain and an evidence-based course of clinical management. The use of sensitive and specific clinical methods to assess the lumbar spine, sacroiliac and hip joints is critical for effective physical examination. Psychosocial factors also play an important role in the evaluation of individuals with low back pain, but are not included in this narrative review of physical examination methods. Physical examination of the lumbar spine, sacroiliac and hip joints is presented, organized around patient position for efficient and effective clinical assessment.

SEMI-CONSTRAINED TOTAL ELBOW ARTHROPLASTY IN CHINESE RHEUMATOID PATIENTS

Seventeen Coonrad-Morrey semi-constrained total elbow replacements were performed on 14 Chinese rheumatoid patients. The elbows were reviewed retrospectively after a mean follow-up of 36 months (range 12–89 months.) After the operation, all patients were satisfied and there was no pain in 15 elbows. There was no radiological sign of loosening in the implanted prostheses and bone graft was incorporated in 93% of primary elbow replacements. The Mayo Elbow Performance Score was improved from an average of 40 (range 20–75) to an average of 93 (range 65–100). The arc of flexion was improved from an average of 89° (range 0°–125°) to 104° (range 35°–125°). The sizes of implants can be predicted accurately by the planning template in only four elbows (24%) and there were early complications in seven elbows (41%), with one prosthesis removed because of deep infection.

A randomized-controlled trial to investigate the effects of rivoglitazone, a novel PPAR gamma agonist on glucose-lipid control in type 2 diabetes

AIM

To examine the efficacy, safety and tolerability of rivoglitazone, a novel thiazolidinedione (TZD), and explore its effects on glucose and lipid control compared to placebo and pioglitazone in Chinese type 2 diabetic patients who are treatment naÏve or treated with a single oral blood glucose-lowering drug.

METHODS

This was a double-blind, randomized, placebo- and active-controlled study. A total of 287 Chinese type 2 diabetic patients with suboptimal glycaemic control (defined as HbA1c ≥6.5 to <10% and fasting plasma glucose ≥7 to ≤15 mmol/l) were enrolled. One hundred and seventy-four eligible patients were randomized into one of the five treatment arms for 12 weeks: placebo, pioglitazone 30 mg daily, rivoglitazone of dose 0.5, 1.0 or 1.5 mg daily. In a full set analysis, we used analysis of covariance to compare the primary endpoint defined as change in HbA1c from baseline to week 12/last observation carried forward in the rivoglitazone group at each dose level with the placebo group.

RESULTS

Changes in HbA1c were -0.11% in the 0.5-mg group; -0.22% in the 1-mg group and -0.17% in the 1.5-mg rivoglitazone group; -0.06% in the 30-mg pioglitazone group and 0.61% in the placebo group. Compared to placebo, changes were significant in all active treatment groups (all p < 0.05). Increase in high-density lipoprotein cholesterol and decrease in triglyceride were observed in the rivoglitazone 1 and 1.5 mg groups, respectively, compared to placebo from baseline to week 12 (p < 0.05). Drug-related oedema was reported in eight patients (7.7%) in all rivoglitazone groups compared to six patients (16.2%) in the pioglitazone group and one patient (3.0%) in the placebo group.

CONCLUSIONS

Rivoglitazone is an efficacious, safe and well-tolerated TZD which improved glycaemic control in Chinese type 2 diabetic patients up to 3 months.

Deep brain stimulation in a Chinese Tourette's syndrome patient

A 31-year-old Chinese man with intractable severe, lifelong Tourette's syndrome characterised by forceful self-injurious motor tics and socially embarrassing vocal tics was treated with bilateral deep brain stimulation. Electrodes were implanted into the thalamic targets at the centromedian-parafascicular complex according to Hassler's nomenclature. A dramatic reduction of tics resulted. At 18 months postoperatively, there was an 81% improvement in his total tics count and a 58% improvement in his Yale Global Tic Severity Scale. His modified Rush video scale decreased from 13 to 8 and visual analogue scale from 10 to 3. These data show that bilateral deep brain stimulation of the thalamus can have a favourable immediate effect on severe tics in a selected group of adult patients suffering from intractable Tourette's syndrome and postoperatively the beneficial effects persisted for at least 18 months.

Photodynamic therapy (PDT) - Initiation of apoptosis via activation of stress-activated p38 MAPK and JNK signal pathway in H460 cell lines

AIMS

The purpose of this study was to investigate the photoefficacies of protoporphyrin IX (PpIX) generated by drug precursor 5-aminolevulinic acid (ALA) and its hexyl ester (H-ALA) on two human non-small lung carcinoma cell lines (H460/Bcl-2 and H460/neo).

MAIN METHODS

Drug uptake and the photoefficacies of PpIX were measured by flow cytometry and MTT assay; while the mode of cell death and alternation of signal transduction pathways were studied with 4',6-diamidino-2-phenylindole (DAPI) staining and Western blot analysis, respectively.

KEY FINDINGS

The flow cytometric analysis of H-ALA (5μM) uptake revealed optimal fluorescent intensity at 8h incubation, while ALA (0.5mM) was still far from saturation. The LD(30) of H-ALA-PDT was 30μM, 2J/cm(2), while the LD(30) of ALA-PDT was 3mM, 2J/cm(2). The dark toxicities mediated by both pro-drug H-ALA and ALA were negligible. By DAPI staining, apoptotic cell death was observed. In addition, by Western blot analysis, H-ALA- and ALA-mediated PDT initiated apoptotic cell death via the up-regulation and activation of p38 mitogen activated protein kinase (MAPK), the stress-activated c-jun N-terminal kinases (JNK) and ERK.

SIGNIFICANCE

These results suggested that H-ALA and ALA mediated PDT displayed similar photocytotoxicities towards the two non-small lung cancer cells. Our present study also demonstrates H-ALA or ALA mediated PDT in H460 cells are closely related to the activation of p38 MAPK and JNK signalling pathway.

Growth of dielectric-embedded silicon nanocrystallites for light-emitting device application

Dielectric films with embedded silicon Si nanocrystallites (Si-Nc) have been recognized as promising light-emitting materials for future integrated photonics based on silicon technology. This work reports a novel method of making this kind of material by high-temperature annealing of Si-rich oxide or nitride films which gives rise to the phase separation reaction and the formation of crystalline silicon nanoclusters in the films. Various characteristics of these materials were studied in detail by using transmission electron microscope, X-ray photoelectron spectroscopy (XPS), Raman, and photoluminescence (PL). Strong transverse optical (TO) mode of Si-Nc at around 516 cm(-1) was found in the Raman spectra of the annealed dielectric films. XPS studies indicate that the Si 2p spectra could be transformed from a random bonding structure (as-deposited) to a random mixing of Si-Nc with stoichiometric oxide or nitride phase after the high-temperature annealing. The energy locations of PL were found to depend on the amount of rich Si and the annealing conditions. Longer and higher temperature annealing can result in the growth of the Si-Nc size and leads to a red-shift of PL. Direct correlation among the crystallite sizes with the PL peaks was found.

DNA damage as a biomarker for assessing the effects of suspended solids on the orange-spotted grouper, Epinephelus coioides

In Hong Kong, suspended solids (SS) introduced by dredging and mud disposal activities are a major cause of mass mortality in cage-cultured marine fish. We have used DNA damage in liver cells, as determined by the comet assay, to assess the impact of SS on the orange-spotted grouper Epinephelus coioides. Seabed sediments were collected from a heavily polluted site in Victoria Harbor and two less polluted sites in Port Shelter and Mirs Bay. Sediments from Victoria Harbor contained higher levels of copper (Cu) and polycyclic aromatic hydrocarbons (PAHs) than those from the other sites. In a 10-day experiment, SS from all three sites induced significant increase in comet tail length, but not in percentage (%) tail DNA. In a 20-day experiment, fish exposed to polluted SS from Victoria Harbor exhibited a significant increase in comet tail length after 5 days and % tail DNA after 10 days. After a 10-day recovery period, however, DNA damage was reduced as tail length and % tail DNA returned to control levels. These results suggest that DNA damage measured by the comet assay is a highly sensitive biomarker for assessing the genotoxic effects of SS to marine fish.