FORMULATION AND EVALUATION OF ATORVASTATIN CALCIUM NANOCRYSTALS CONTAINING P-GLYCOPROTEIN INHIBITORS FOR ENHANCING ORAL DELIVERY

Objective: The main objective of this study was to develop atorvastatin calcium (ATR) as an oral drug delivery system for a P-glycoprotein (P-gp) substrate drug using different pharmaceutical excipients that inhibit P-glycoprotein and evaluate the influence of nanocrystals on the dissolution characteristics and bioavailability compared to the plain drug. Methods: A nanosuspension was prepared by Solvent-antisolvent precipitation method using a solvent containing stabilizer that act as a p-gp inhibitor dissolved in distilled water as polyethylene glycol 300, polyethylene glycol 400 (PEG 300, PEG 400), tween 20 and tween 80 while the solvent selected for atorvastatin calcium was methanol. The concentrations were as follows: PEG 300 and 400 = 0.25% w/v, tween 20 and 80 = 0.75% v/v. Nanocrystals were extracted from the suspension and characterized. Results: Particle size of the drug was 1307±127.79 nm while the formulas prepared ranged from 223±17.67 to 887±58.12 nm. Pure ATR had a saturated solubility of 0.059±0.005 mg/ml and the prepared nanocrystals ranged from 0.32±0.021 to 0.88±0.019 mg/ml. The Percentage of drug released of plain atorvastatin calcium reached 41.49% while the formula ranged from 44.32 to 61.5%. Both XRD and SEM discussed the degree of crystallinity as follows: F1<F2<F4<F3<ATR. Conclusion: 0.3% of PEG 300 and PEG 400 were not enough to formulate proper nanocrystals while 0.75% tween 20 and tween 80 achieved acceptable formulas. F4 which is prepared with tween 80 exhibited the highest enhancement in saturated solubility, dissolution rate and subsequently expected to have improved oral bioavailability

Estimating multiple greenspace exposure types and their associations with neighbourhood premature mortality: A socioecological study.

BACKGROUND: Greenspace exposures are often measured using single exposure metrics, which can lead to conflicting results. Existing methodologies are limited in their ability to estimate greenspace exposure comprehensively. We demonstrate new methods for estimating single and combined greenspace exposure metrics, representing multiple exposure types that combine impacts at various scales. We also investigate the association between those greenspace exposure types and premature mortality. METHODS: We used geospatial data and spatial analytics to model and map greenspace availability, accessibility and eye-level visibility exposure metrics. These were harmonised and standardised to create a novel composite greenspace exposure index (CGEI). Using these metrics, we investigated associations between greenspace exposures and years of potential life lost (YPLL) for 1673 neighbourhoods applying spatial autoregressive models. We also investigated the variations in these associations in conjunction with levels of socioeconomic deprivation based on the index of multiple deprivations. RESULTS: Our new CGEI metric provides the opportunity to estimate spatially explicit total greenspace exposure. We found that a 1-unit increase in neighbourhood CGEI was associated with approximately a 10-year reduction in YPLL. Meaning a 0.1 increment or 10% increase in the CGEI is associated with an approximately one year lower premature mortality value. A single 1-unit increase in greenspace availability was associated with a YPLL reduction of 9.8 years, whereas greenness visibility related to a reduction of 6.14 years. We found no significant association between greenspace accessibility and YPLL. Our results further identified divergent trends in the relations between greenspace exposure types (e.g. availability vs. accessibility) and levels of socioeconomic deprivation (e.g. least vs. most). CONCLUSION: Our methods and metrics provide a novel approach to the assessment of multiple greenspace exposure types, and can be linked to the broader exposome framework. Our results showed that a higher composite greenspace exposure is associated with lower premature mortality

Estimating multiple greenspace exposure types and their associations with neighbourhood premature mortality: A socioecological study.

BACKGROUND: Greenspace exposures are often measured using single exposure metrics, which can lead to conflicting results. Existing methodologies are limited in their ability to estimate greenspace exposure comprehensively. We demonstrate new methods for estimating single and combined greenspace exposure metrics, representing multiple exposure types that combine impacts at various scales. We also investigate the association between those greenspace exposure types and premature mortality. METHODS: We used geospatial data and spatial analytics to model and map greenspace availability, accessibility and eye-level visibility exposure metrics. These were harmonised and standardised to create a novel composite greenspace exposure index (CGEI). Using these metrics, we investigated associations between greenspace exposures and years of potential life lost (YPLL) for 1673 neighbourhoods applying spatial autoregressive models. We also investigated the variations in these associations in conjunction with levels of socioeconomic deprivation based on the index of multiple deprivations. RESULTS: Our new CGEI metric provides the opportunity to estimate spatially explicit total greenspace exposure. We found that a 1-unit increase in neighbourhood CGEI was associated with approximately a 10-year reduction in YPLL. Meaning a 0.1 increment or 10% increase in the CGEI is associated with an approximately one year lower premature mortality value. A single 1-unit increase in greenspace availability was associated with a YPLL reduction of 9.8 years, whereas greenness visibility related to a reduction of 6.14 years. We found no significant association between greenspace accessibility and YPLL. Our results further identified divergent trends in the relations between greenspace exposure types (e.g. availability vs. accessibility) and levels of socioeconomic deprivation (e.g. least vs. most). CONCLUSION: Our methods and metrics provide a novel approach to the assessment of multiple greenspace exposure types, and can be linked to the broader exposome framework. Our results showed that a higher composite greenspace exposure is associated with lower premature mortality

Spatial dimensions of the influence of urban green-blue spaces on human health: A systematic review.

BACKGROUND: There is an increasing volume of literature investigating the links between urban environments and human health, much of which involves spatial conceptualisations and research designs involving various aspects of geographical information science. Despite intensifying research interest, there has been little systematic investigation of pragmatic methodological concerns, such as how studies are realised in terms of the types of data that are gathered and the analytical techniques that are applied, both of which have the potential to impact results. The aim of this systematic review is, therefore, to understand how spatial scale, datasets, methods, and analytics are currently applied in studies investigating the relationship between green and blue spaces and human health in urban areas. METHOD: We systematically reviewed 93 articles following PRISMA protocol, extracted information regarding different spatial dimensions, and synthesised them in relation to various health indicators. RESULTS AND DISCUSSION: We found a preponderance of the use of neighbourhood-scale in these studies, and a majority of the studies utilised land-use and vegetation indices gleaned from moderate resolution satellite imagery. We also observed the frequent adoption of fixed spatial units for measuring exposure to green and blue spaces based on physical proximity, typically ranging between 30 and 5000 m. The conceptual frameworks of the studies (e.g., the focus on physical vs. mental health or the definition of exposure to green space) were found to have an influence on the strength of association between exposure and health outcomes. Additionally, the strength and significance of associations also varied by study design, something which has not been considered systematically. CONCLUSION: On the basis of our findings, we propose a set of recommendations for standardised protocols and methods for the evaluation of the impact of green-blue spaces on health. Our analysis suggests that future studies should consider conducting analyses at finer spatial scales and employing multiple exposure assessment methods to achieve a comprehensive and comparable evaluation of the association between greenspace and health along multiple pathways

Video-Assisted Thoracoscopic Surgery versus Open Decortication in Chronic Pleural Empyema

Background: The role of video-assisted thoracoscopic surgery (VATS) for managing organized empyema is still limited. This study compared VATS versus open decortication in patients with chronic pleural empyema. Methods: This randomized controlled trial included 58 patients with stage III empyema. Patients were divided into two groups. Group A (n= 30) included patients who had decortication through an open thoracotomy, and Group B (n= 28) included VATS decortication patients. Two patients in the VATS group were converted to the open approach and were excluded from the analysis. Results: The mean age in Group A was 48.23 ± 8.44 years and 49.79 ± 7.85 years Group B (p= 0.47). There were 16 males (53.3%) in Group A and 15 (63.6%) in Group B (p= 0.99). The operative time was 336.0 ± 67.60 min in Group A and 291.07 ± 56.66 min in Group B (p= 0.01). There was no difference in intraoperative complications between groups. Postoperative hospital stay (p= 0.23) and ICU admission (p= 0.24) did not differ between groups. In Group A, the pain scale was 8 (6- 8), and it was 4 (2- 4) in Group B (p˂ 0.001). No difference was recorded in the postoperative complications between groups. Conclusion:  The outcomes of VATS in managing stage III empyema are comparable to the open approach. VATS has the advantage of lower postoperative pain. VATS could be an alternative to open decortication in patients with stage III pleural empyema

Nano-risk Science: application of toxicogenomics in an adverse outcome pathway framework for risk assessment of multi-walled carbon nanotubes

BACKGROUND: A diverse class of engineered nanomaterials (ENMs) exhibiting a wide array of physical-chemical properties that are associated with toxicological effects in experimental animals is in commercial use. However, an integrated framework for human health risk assessment (HHRA) of ENMs has yet to be established. Rodent 2-year cancer bioassays, clinical chemistry, and histopathological endpoints are still considered the ‘gold standard’ for detecting substance-induced toxicity in animal models. However, the use of data derived from alternative toxicological tools, such as genome-wide expression profiling and in vitro high-throughput assays, are gaining acceptance by the regulatory community for hazard identification and for understanding the underlying mode-of-action. Here, we conducted a case study to evaluate the application of global gene expression data in deriving pathway-based points of departure (PODs) for multi-walled carbon nanotube (MWCNT)-induced lung fibrosis, a non-cancer endpoint of regulatory importance. METHODS: Gene expression profiles from the lungs of mice exposed to three individual MWCNTs with different physical-chemical properties were used within the framework of an adverse outcome pathway (AOP) for lung fibrosis to identify key biological events linking MWCNT exposure to lung fibrosis. Significantly perturbed pathways were categorized along the key events described in the AOP. Benchmark doses (BMDs) were calculated for each perturbed pathway and were used to derive transcriptional BMDs for each MWCNT. RESULTS: Similar biological pathways were perturbed by the different MWCNT types across the doses and post-exposure time points studied. The pathway BMD values showed a time-dependent trend, with lower BMDs for pathways perturbed at the earlier post-exposure time points (24 h, 3d). The transcriptional BMDs were compared to the apical BMDs derived by the National Institute for Occupational Safety and Health (NIOSH) using alveolar septal thickness and fibrotic lesions endpoints. We found that regardless of the type of MWCNT, the BMD values for pathways associated with fibrosis were 14.0–30.4 μg/mouse, which are comparable to the BMDs derived by NIOSH for MWCNT-induced lung fibrotic lesions (21.0–27.1 μg/mouse). CONCLUSIONS: The results demonstrate that transcriptomic data can be used to as an effective mechanism-based method to derive acceptable levels of exposure to nanomaterials in product development when epidemiological data are unavailable. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12989-016-0125-9) contains supplementary material, which is available to authorized users

Subchronic oral exposure to benzo(a)pyrene leads to distinct transcriptomic changes in the lungs that are related to carcinogenesis

We have previously shown that acute oral exposure to the environmental carcinogen benzo(a)pyrene (BaP) elicits comparable levels of DNA adducts, but distinct transcriptomic changes, in mouse lungs and livers, the two main BaP bioactivating organs. Oral BaP exposure is predominantly associated with lung cancer and not hepatic cancer in some animal models, suggesting that gene expression differences may provide insight into the drivers of tissue-specific carcinogenesis. In the present study, we examine pulmonary DNA adduct formation, lacZ mutant frequency, and mRNA profiles in adult male MutaMouse following subchronic (28 day) oral exposure to BaP (0, 25, 50, and 75mg/kg/day) and sacrificed 3 days postexposure. The results are compared with those obtained from livers of the same mice (previously published). Although there was a 1.8- to 3.3-fold increase in the levels of DNA adducts in lung compared with liver, the lacZ transgene mutant frequency was similar in both tissues. At the transcriptomic level, a transition from activation of the DNA damage response p53 pathway at the low dose to the induction of genes involved in angiogenesis, evasion of apoptosis and growth signals at the high doses was evident only in the lungs. These results suggest that tissue DNA adducts and mutant frequency are sensitive markers of target tissue exposure and mode of action, whereas early changes in gene expression may provide a better indication of the likelihood of carcinogenic transformation in selected tissues. Moreover, the study provides new information on the underlying mecha- nisms that contribute to tissue-specific responses to BaP

Portrait of blood-derived extracellular vesicles in patients with Parkinson's disease.

The production of extracellular vesicles (EV) is a ubiquitous feature of eukaryotic cells but pathological events can affect their formation and constituents. We sought to characterize the nature, profile and protein signature of EV in the plasma of Parkinson's disease (PD) patients and how they correlate to clinical measures of the disease. EV were initially collected from cohorts of PD (n = 60; Controls, n = 37) and Huntington's disease (HD) patients (Pre-manifest, n = 11; manifest, n = 52; Controls, n = 55) - for comparative purposes in individuals with another chronic neurodegenerative condition - and exhaustively analyzed using flow cytometry, electron microscopy and proteomics. We then collected 42 samples from an additional independent cohort of PD patients to confirm our initial results. Through a series of iterative steps, we optimized an approach for defining the EV signature in PD. We found that the number of EV derived specifically from erythrocytes segregated with UPDRS scores corresponding to different disease stages. Proteomic analysis further revealed that there is a specific signature of proteins that could reliably differentiate control subjects from mild and moderate PD patients. Taken together, we have developed/identified an EV blood-based assay that has the potential to be used as a biomarker for PD

Prospective randomized trial of iliohypogastric-ilioinguinal nerve block on post-operative morphine use after inpatient surgery of the female reproductive tract

<p>Abstract</p> <p>Objective</p> <p>To determine the impact of pre-operative and intra-operative ilioinguinal and iliohypogastric nerve block on post-operative analgesic utilization and length of stay (LOS).</p> <p>Methods</p> <p>We conducted a prospective randomized double-blind placebo controlled trial to assess effectiveness of ilioinguinal-iliohypogastric nerve block (IINB) on post-operative morphine consumption in female study patients (<it>n </it>= 60). Patients undergoing laparotomy via Pfannenstiel incision received injection of either 0.5% bupivacaine + 5 mcg/ml epinephrine for IINB (Group I, <it>n </it>= 28) or saline of equivalent volume given to the same site (Group II, <it>n </it>= 32). All injections were placed before the skin incision and after closure of rectus fascia via direct infiltration. Measured outcomes were post-operative morphine consumption (and associated side-effects), visual analogue pain scores, and hospital length of stay (LOS).</p> <p>Results</p> <p>No difference in morphine use was observed between the two groups (47.3 mg in Group I vs. 45.9 mg in Group II; <it>p </it>= 0.85). There was a trend toward lower pain scores after surgery in Group I, but this was not statistically significant. The mean time to initiate oral narcotics was also similar, 23.3 h in Group I and 22.8 h in Group II (<it>p </it>= 0.7). LOS was somewhat shorter in Group I compared to Group II, but this difference was not statistically significant (<it>p </it>= 0.8). Side-effects occurred with similar frequency in both study groups.</p> <p>Conclusion</p> <p>In this population of patients undergoing inpatient surgery of the female reproductive tract, utilization of post-operative narcotics was not significantly influenced by IINB. Pain scores and LOS were also apparently unaffected by IINB, indicating a need for additional properly controlled prospective studies to identify alternative methods to optimize post-surgical pain management and reduce LOS.</p