The Putative Role of Pathogenic Oral Microorganisms in Chronic Kidney Disease

Chronic kidney disease and chronic periodontitis are common diseases that are found disproportionately comorbid with each other and have been reported to have a detrimental effect on the progression of each respective disease. They have an overlap in risk factors and both are underpinned by systemic inflammation along with a wide selection of immunological and non-specific effects that can affect the body over the lifespan of the conditions. The oral microorganisms involved in chronic periodontitis have demonstrated the ability to translocate and elicit distal effects in a variety of systemic diseases but currently there has been little research into the associations with chronic kidney disease. Previous studies have investigated the directionality of the relationship between these two diseases; however, there is a lack of evidence on how these diseases may be interacting at the local sites such as the oral cavity and systemic level, especially looking at periodontitis associated microbial products that could damage the kidneys. The aim of this study was to investigate the microbial products produced by periodontitis associated microorganisms using a novel metabolomics approach and identify if any of these products are capable of eliciting in vitro a cytotoxic (cell viability testing), migratory (wound healing assay) and fibrotic response (qPCR) in renal cells. A selection of microorganisms associated with periodontitis were cultivated in a novel media representative of the diseased environment, and the microbial products secreted in bacterial supernatants over their lifecycle were collected. These supernatants were prepared for testing by centrifugation and filtering at 0.2 µM in order to remove microbial cells; the prepared samples were stored at -80oC. A novel metabolomics approach utilising liquid chromatography mass spectroscopy was developed and trialled as a fast screening method for identifying potentially toxic metabolites but it was not suitable for this study. Testing of the collected microbial supernatants against human kidney cells identified that only Porphyromonas gingivalis supernatants were capable of inducing a cytotoxic and mild anti-migratory effect. Tests to identify the causative agent behind XV these effects suggest this effect could be protein derived, as the addition of a protease inhibitor attenuated the cytotoxic effects of the supernatants, suggesting the role of microbe specific proteases known as Gingipains. Investigations in the fibrotic potential of the collected supernatants showed that only Porphyromonas gingivalis supernatants were capable of significantly inducing the production of a three pro-fibrotic markers: Collagen, type I, alpha 1, transforming growth factor β and tissue inhibitor of metalloproteinases 1. In conclusion, this study showed that one periodontitis associated microorganism, Porphyromonas gingivalis is capable of eliciting cytotoxic and mild anti-migratory effects in renal cells, along with inducing the production of three pro-fibrotic markers. This study sheds light on how this key microorganism may pay a role in the mediation of chronic kidney disease

Surfactant coated aerosol powders and their properties

The hygroscopic growth of aerosols is an important factor effecting particle size. The consequence of the hygroscopic growth of pharrnaceutical aerosols is a change in their deposition characteristics, such that there is an increase in the total amount deposited in the lung. In this study the hygroscopic growth of disodium fluorescein (DF) aerosol powders was investigated by coating the powders with lauric and capric acids. The coating procedure was carried out in dichloromethane and chloroform, which acted as cosolvents for the fatty acids. An assessment of the extent and the nature of the coating was carried out. The qualitative assessment of the coating was achieved by infra-red spectroscopy, electronscanning chemical analysis and scanning electron microscopy. The quantitative analysis was carried out by differential refractometry, ultra-violet spectroscopy and gas liquid chromatography. These powders were generated under conditions approaching those in the lung, of 97 % relative humidity and 37"C. Coated and uncoated DF aerosol powders were introduced into a controlled temperature and relative humidity apparatus, designed and constructed for the investigation of hygroscopic growth in these studies. A vertical spinning disc device was used to generate the powders. Under conditions of controlled temperature and relative humidity mentioned, the growth ratio of disodium fluorescein alone was 1.45 compared with 1.68, for a nominal coating of DF with lauric acid of 0.12 gg-1, 1.0 for a nominal lauric acid coating of 0.2 gg-1, and 1.02 for a nominal capric acid coating of 0.18 gg-1. The range of control of hygroscopic growth of these aerosols has implications for the deposition of these preparations in the respiratory tract. These implications are discussed in the light of the current knowledge of the effects of hygroscopic growth on the deposition of pharmaceutical and environmental aerosols. A series of experiments in which pulmonary ventilation using a simple radioaerosol generator and delivery system are reported showing that particle size determination may be used to aid the design of diagnostic aerosol generators

Effect of chloroquine on phagolysosomal fusion in cultured guinea pig alveolar macrophages: Implications in drug delivery

The aim of this study was to evaluate the effects of chloroquine on phagolysosomal fusion (PLF) in cultured guinea pig alveolar macrophages (AMs). This technique may be of significance for antitubercular drugs, because the survival of Mycobacterium tuberculosis is linked to evasion of PLF. Guinea pig AMs were obtained from anesthetized animals after exsanguination. The AMs were cultured at a density of 1×106 cell/mL in 24-well plates after attachment to 13-mm coverslips. Culture conditions were at 37°C, with 95% air/5% CO2 in Roswell Park Memorial Institute (RPMI) 1640 medium with 10% heat-inactivated fetal bovine serum. Rhodamine-dextran (70 kd) was incubated with the cells at 0.25 mg/mL for 24 hours to label the lysosomes. Chloroquine treatment where indicated was performed at 10–20 μ g/mL for 1 hour. Fluorescent BioParticles were then added, and PLF was monitored by formation of an organge-yellow fluorescence on fusion of green fluorescent BioParticles with rhodamine-labeled lysosomes. PLF endpoints were measured by scoring for the percentage of orange-yellow cells in the field of view. Image analysis to measure the intensity of the orange-yellow color was performed by obtaining a, b values for 5×5 pixel areas using the Photo Adobe program 4.0.1

The 2009 Samoa and 2010 Chile Tsunamis as Observed in the Ionosphere using GPS Total Electron Content

Ground‐based Global Positioning System (GPS) measurements of ionospheric total electron content (TEC) show variations consistent with atmospheric internal gravity waves caused by ocean tsunamis following two recent seismic events: the Samoa earthquake of 29 September 2009 and the Chile earthquake of 27 February 2010. Both earthquakes produced ocean tsunamis that were destructive to coastal communities near the epicenters, and both were observed in tidal gauge and buoy measurements throughout the Pacific Ocean. We observe fluctuations in TEC correlated in time, space, and wave properties with these tsunamis using the Jet Propulsion Laboratory’s Global Ionospheric Mapping software. These TEC measurements were band‐pass filtered to remove ionospheric TEC variations with wavelengths and periods outside the typical range for tsunamis. Observable variations in TEC appear correlated with the tsunamis in some locations (Hawaii and Japan), but not in others (Southern California or near the epicenters). Where variations are observed, the typical amplitude tends to be ∼0.1–0.2 TEC units for these events, on the order of ∼1% of the background TEC value. These observations are compared to estimates of expected tsunami‐driven TEC variations produced by Embry Riddle Aeronautical University’s Spectral Full Wave Model, an atmosphere‐ionosphere coupled model, and are found to be in good agreement. Significant TEC variations are not always seen when a tsunami is present, but in these two events the regions where a strong ocean tsunami was observed coincided with clear TEC observations, while a lack of clear TEC observations coincided with smaller sea surface height amplitudes. There exists the potential to apply these detection techniques to real‐time GPS TEC data, providing estimates of tsunami speed and amplitude that may be useful for early warning systems

Can we use biomarkers of coagulation to predict which patients with foot and ankle injury will develop vein thrombosis?

Background Our aim was to determine whether plasma levels of Tissue Factor (TF), Vascular Cell Adhesion Molecule 1 (VCAM-1), Interleukin 6 (IL-6) or D-dimer after foot and ankle injury could predict which patients would develop deep vein thrombosis (DVT). Methods Patients aged 18–60 years with acute foot and ankle injury had venous blood sample to measure TF, VCAM-1, IL-6 and D-dimer within 3 days of injury. Patients had bilateral lower limb venous ultrasound to assess for DVT on discharge from clinic. Results 21 of 77 patients were found to have DVT (27%). There was no statistically significant association between levels of TF, VCAM-1, IL-6 or D-dimer and subsequent development of DVT. Conclusion Tissue Factor (TF), Vascular Cell Adhesion Molecule-1 (VCAM-1), Interleukin-6 (IL-6) and D-dimer levels were not associated with development deep vein thrombosis in patients with acute foot and ankle injury