Inhalation of sulfur mustard causes long-term T cell-dependent inflammation: possible role of Th17 cells in chronic lung pathology

Sulfur mustard (SM) is a highly toxic chemical warfare agent that remains a threat to human health. The immediate symptoms of pulmonary distress may develop into chronic lung injury characterized by progressive lung fibrosis, the major cause of morbidity among the surviving SM victims. Although SM has been intensely investigated, little is known about the mechanism(s) by which SM induces chronic lung pathology. Increasing evidence suggests that IL-17(+) cells are critical in fibrosis, including lung fibrotic diseases. In this study we exposed F344 rats and cynomolgus monkeys to SM via inhalation and determined the molecular and cellular milieu in their lungs at various times after SM exposure. In rats, SM induced a burst of pro-inflammatory cytokines/chemokines within 72 h, including IL-1β, TNF-α, IL-2, IL-6, CCL2, CCL3, CCL11, and CXCL1 that was associated with neutrophilic infiltration into the lung. At 2 wks and beyond (chronic phase), lymphocytic infiltration and continued elevated expression of cytokines/chemokines were sustained. TGF-β, which was undetectable in the acute phase, was strongly upregulated in the chronic phase; these conditions persisted until the animals were sacrificed. The chronic phase was also associated with myofibroblast proliferation, collagen deposition, and presence of IL-17(+) cells. At ≥30 days, SM inhalation promoted the accumulation of IL-17(+) cells in the inflamed areas of monkey lungs. Thus, SM inhalation causes acute and chronic inflammatory responses; the latter is characterized by the presence of TGF-β, fibrosis, and IL-17(+) cells in the lung. IL-17(+) cells likely play an important role in the pathogenesis of SM-induced lung injury.     

Genetically modified endothelial progenitor cells in the therapy of cardiovascular disease and pulmonary hypertension

Since their initial discovery, endothelial progenitor cells (EPCs) have held tremendous promise for cell therapy for a variety of cardiovascular diseases including pulmonary hypertension. The clinical experience to date suggests that circulating or bone marrow mononuclear cells and EPCs can induce neovascularization, and enhance cardiac repair after myocardial function, as well as improvements in the hemodynamic and functional status of patients with idiopathic pulmonary arterial hypertension. Although these results are promising, the overall magnitude of the clinical benefits seen in these trials appear to be rather modest. Indeed, strong experimental evidence points towards a reduction in mobilization and impairment in function of EPCs in preclinical models and patients with cardiac disease or with cardiovascular risk factors such as advanced age, type I and II diabetes, hypercholesterolemia, coronary artery disease, as well as other conditions such as pulmonary hypertension. Genetic engineering of EPCs ex vivo, prior to transplantation, is a promising cell-enhancement strategy for restoring the angiogenic potential of autologous, patient-derived cells. This review provides an update of the experimental studies that have used gene-modified EPC therapy to treat ischemic cardiovascular disease and pulmonary hypertension.     

The Development of Thermal Nanoprobe Methods as a Means of Characterizing and Mapping Plasticizer Incorporation into Ethylcellulose Films

Purpose

The phase composition and distribution of ethylcellulose (EC) films containing varying amounts of the plasticizer fractionated coconut oil (FCO) were studied using a novel combination of thermal and mapping approaches.

Methods

The thermal and thermomechanical properties of films containing up to 30% FCO were characterized using modulated temperature differential scanning calorimetry (MTDSC) and dynamic mechanical analysis (DMA). Film surfaces were mapped using atomic force microscopy (AFM; topographic and pulsed force modes) and the composition of specific regions identified using nanothermal probes.

Results

Clear evidence of distinct conjugate phases was obtained for the 20?C30% FCO/EC film systems. We suggest a model whereby the composition of the distinct phases may be estimated via consideration of the glass transition temperatures observed using DSC and DMA. By combining pulsed force AFM and nano-thermal analysis we demonstrate that it is possible to map the two separated phases. In particular, the use of thermal probes allowed identification of the distinct regions via localized thermomechanical analysis, whereby nanoscale probe penetration is measured as a function of temperature.

Conclusion

The study has indicated that by using thermal and imaging techniques in conjunction it is possible to both identify and map distinct regions in binary films.     

Arsenic toxicity in a sediment-dwelling polychaete: detoxification and arsenic metabolism

The accumulation, subcellular distribution and speciation of arsenic in the polychaete Arenicola marina were investigated under different laboratory exposure conditions representing a range of metal bioavailabilities, to gain an insight into the physiological mechanisms of how A. marina handles bioaccumulated arsenic and to improve our understanding of the potential ecotoxicological significance of bioaccumulated arsenic in this deposit-feeder. The exposure conditions included exposure to sublethal concentrations of dissolved arsenate, exposure to sublethal concentrations of sediment-bound metal mining mixtures, and exposure to lethal concentrations of sediment-bound metal mining mixtures and arsenic- and multiple metal-spiked sediments. The sub-lethal exposures indicate that arsenic bioaccumulated by the deposit-feeding polychaete A. marina is stored in the cytosol as heat stable proteins (~50%) including metallothioneins, possibly as As (III)-thiol complexes. The remaining arsenic is mainly accumulated in the fraction containing cellular debris (~20%), with decreasing proportions accumulated in the metal-rich granules, organelles and heat-sensitive proteins fractions. A biological detoxified metal compartment including heat stable proteins and the fraction containing metal-rich granules is capable of binding arsenic coming into the cells at a constant rate under sublethal arsenic bioavailabilities. The remaining arsenic entering the cell is bound loosely into the cellular debris fraction, which can be subsequently released and diverted to an expanding detoxified pool. Our results suggest that a metal sensitive compartment comprising the cellular debris, enzymes and organelles fractions may be more representative of the toxic effects observed.     

Transparent, tough collagen laminates prepared by oriented flow casting, multi-cyclic vitrification and chemical cross-linking

The lamellar architecture found in many natural fibrous tissues has a significant bearing on their specific functions. However, current engineered tissues have simultaneously no realistic structures and no adequate functions. This study demonstrates a two-step process for obtaining structurally mimicking laminates in natural fibrous tissues with good optical and mechanical characters from purified-clinically-safe collagen molecules. Stacked lamella structures can be created by repeating flow casting, with the controlling parallel/orthogonal directionalities of each thin single-layer (2-5 μm in thickness). The transparency of laminates is successfully improved by a unique multi-cyclic vitrification with chemical cross-linking. The directionalities of optical and mechanical functions in laminates are strongly related with the preferential collagen alignments in the laminates. The tensile strength of laminates is extremely higher than any other engineered materials as well as native cornea, which exhibit an orthogonal laminated collagen structure and a good optical transmission.     

Toxicity of silver nanoparticles - nanoparticle or silver ion?

The toxicity of silver nanoparticles (AgNPs) has been shown in many publications. Here we investigated to which degree the silver ion fraction of AgNP suspensions, contribute to the toxicity of AgNPs in A549 lung cells. Cell viability assays revealed that AgNP suspensions were more toxic when the initial silver ion fraction was higher. At 1.5 μg/ml total silver, A549 cells exposed to an AgNP suspension containing 39% silver ion fraction showed a cell viability of 92%, whereas cells exposed to an AgNP suspension containing 69% silver ion fraction had a cell viability of 54% as measured by the MTT assay. In addition, at initial silver ion fractions of 5.5% and above, AgNP-free supernatant had the same toxicity as AgNP suspensions. Flow-cytometric analyses of cell cycle and apoptosis confirmed that there is no significant difference between the treatment with AgNP suspension and AgNP supernatant. Only AgNP suspensions with silver ion fraction of 2.6% or less were significantly more toxic than their supernatant as measured by MTT assays. From our data we conclude that at high silver ion fractions (≥5.5%) the AgNPs did not add measurable additional toxicity to the AgNP suspension, whereas at low silver ion fractions (≤2.6%) AgNP suspensions are more toxic than their supernatant.     

An investigation into water interactions with amorphous and milled salbutamol sulphate: the development of predictive models for uptake and recrystallization

An investigation into the effect of water uptake on the glass transition of spray dried and milled salbutamol sulphate has been performed, with a particular view to exploring how the water uptake, T(g) value and recrystallization behaviour correlate. Samples of milled and spray dried drug were stored under controlled humidity conditions and the T(g) measured as a function of time. The T(g) was measured using modulated temperature differential scanning calorimetry (MTDSC) while the water content was measured using thermogravimetric analysis (TGA). A correlation was found between time of storage, water content and T(g) in that the samples showed time dependent equilibration with the storage environment (either gaining or losing water depending on the RH). The relationship between water content and stability, based on the concept of T(g) lowering, was modelled using the semi-empirical approach of Royall et al. (1999) as well as a derivation of the Kwei equation which allowed the interaction between the water and substrate to be accounted for. A method for predicting stability based on two simple DSC runs is proposed. In addition, we discuss the observation of a double glass transition for the spray dried samples.     

Lauroylethanolamide and linoleoylethanolamide improve functional outcome in a rodent model for stroke

Ischemic stroke is a significant health problem affecting over 6 million people in the United States alone. In addition to surgical and thrombolytic therapeutic strategies for stroke, neuroprotective therapies may offer additional benefit. N-acylethanolamines (NAEs) are signaling lipids whose synthesis is upregulated in response to ischemia, suggesting that they may be neuroprotective. To date only three NAEs, arachidonylethanolamide (NAE 20:4), palmitoylethanolamide (NAE 16:0) and oleoylethanolamide (NAE 18:1) have shown to exert neuroprotective effect in animal models for stroke. Here, we describe neuroprotective effects of the hitherto uncharacterized NAEs, lauroylethanolamide (NAE 12:0) and linoleoylethanolamide (NAE 18:2) in a middle cerebral artery occlusion model of stroke. Pretreatment with NAE 18:2 prior to ischemia/reperfusion (I/R) injury resulted in both significantly reduced cortical infarct volume and improved functional outcome as determined using the neurological deficit score. NAE 12:0 improved neurological deficits without a significant reduction lesion size. Our results suggest that NAEs, as a whole, provide neuroprotection during I/R injury and may have therapeutic benefit when used as complementary treatment with other therapies to improve stroke outcome.