Evaluation of the Photostability and Photodynamic Efficacy of Rose Bengal Loaded in Multivesicular Liposomes

Purpose: Rose Bengal (RB) is a potential photodynamic sensitizer in anticancer therapy. The purpose of this study was to prepare multivesicular liposomes (MVL) loaded with RB to enhance its photostability and intracellulaer photodynamic efficacy.Methods: Four MVL-RB formulations were prepared by reverse phase evaporation technique using a double emulsion method. The photostability of RB in phosphate buffer and in MVL was studied by monitoring the change in its absorption spectra at different time points following photoirradiation at 550 nm. Photodynamic cytotoxicity, intracellular uptake and localization of the most photostable MVL-RB were studied on baby hamster kidney fibroblasts to evaluate its photodynamic efficacy, compared with free RB.Results: MVL-RB demonstrated significantly slower photodegradation rates with 10-fold extended halflife compared with free RB in buffer (p < 0.05). The degradation followed pseudo first order kinetics. Photodynamic cytotoxicity studies revealed that MVL-RB increased cell mortality by 1.6 - 2.5-fold, compared to free RB, and this could be attributed to its enhanced intracellular uptake and different localization pattern in the cell, in addition to increased photostability. Conclusion: Loading RB in MVL is a promising approach to improve the photodynamic efficacy of RB, by enhancing its photostability and delivery into cells.Keywords: Rose Bengal, Photodynamic therapy, Multivesicular liposomes, Photostability, Phototoxicit

Healthcare Providers' Knowledge and Current Practice of Pain Assessment and Management: How Much Progress Have We Made?

Context: Despite improvement in pain management and availability of clinical treatment guidelines, patients in Jordan are still suffering from pain. Negative consequences of undertreated pain are being recognized as a reason for further illnesses and poor quality of life. Healthcare providers (HCPs) are responsible for relieving pain of their patients. Objective: To evaluate the knowledge and attitudes of HCPs toward pain management in Jordan. Methods: A 16-item questionnaire with agree or disagree options was given to 662 HCPs in seven hospitals in Jordan who volunteered to participate in the study. Following data collection, the responses were coded and entered into SPSS. Results: There was a statistically significant difference (p < 0.004) in percentage scores between physicians (36%) and pharmacists (36%) versus nurses (24%). The level of knowledge was the best among physicians, followed by pharmacists specifically in the area of cancer pain management. Nurses scored the lowest for knowledge of pain assessment and management among HCPs. However, HCPs overall scores indicated insufficient knowledge specifically in relation to pain assessment and management among children

Reducing care-resistant behaviors during oral hygiene in persons with dementia

Abstract Background Nursing home residents with dementia are often dependent on others for mouth care, yet will react with care-resistant behavior when receiving assistance. The oral health of these elders deteriorates in the absence of daily oral hygiene, predisposing them to harmful systemic problems such as pneumonia, hyperglycemia, cardiac disease, and cerebral vascular accidents. The purpose of this study is to determine whether care-resistant behaviors can be reduced, and oral health improved, through the application of an intervention based on the neurobiological principles of threat perception and fear response. The intervention, called Managing Oral Hygiene Using Threat Reduction, combines best mouth care practices with a constellation of behavioral techniques that reduce threat perception and thereby prevent or de-escalate care-resistant behaviors. Methods/Design Using a randomized repeated measures design, 80 elders with dementia from 5 different nursing homes will be randomized at the individual level to the experimental group, which will receive the intervention, or to the control group, which will receive standard mouth care from research team members who receive training in the proper methods for providing mouth care but no training in resistance recognition or prevention/mediation. Oral health assessments and care-resistant behavior measurements will be obtained during a 7-day observation period and a 21-day intervention period. Individual growth models using multilevel analysis will be used to estimate the efficacy of the intervention for reducing care-resistant behaviors in persons with dementia, and to estimate the overall efficacy of the intervention using oral health outcomes. Activity-based costing methods will be used to determine the cost of the proposed intervention. Discussion At the conclusion of this study, the research team anticipates having a proven intervention that prevents and reduces care-resistant within the context of mouth care. Long-term objectives include testing the effect of the intervention on systemic illnesses among persons with dementia; examining the transferability of this intervention to other activities of daily living; and disseminating threat reduction interventions to nursing home staff, which may radically change the manner in which care is provided to persons with dementia. Trial Registration ClinicalTrials.gov: NCT01363258http://deepblue.lib.umich.edu/bitstream/2027.42/112778/1/12903_2011_Article_198.pd

Effect of Depth of Total Intravenous General Anesthesia on Intraoperative Electrically Evoked Compound Action Potentials in Cochlear Implantation Surgery.

PURPOSE: This study aims to compare the effect of the depth of total intravenous anesthesia (TIVA) on intraoperative electrically evoked compound action potential (e-ECAP) thresholds in cochlear implant operations. METHODS: Prospectively, a total of 39 patients aged between 1 and 48 years who were scheduled to undergo cochlear implantation surgeries were enrolled in this study. Every patient received both light and deep TIVA during the cochlear implant surgery. The e-ECAP thresholds were obtained during the light and deep TIVA. RESULTS: After comparing the e-ECAP means for each electrode (lead) between the light and deep anesthesia, no significant differences were detected between the light and deep anesthesia. CONCLUSION: The depth of TIVA may have no significant influence on the e-ECAP thresholds as there was no statistical difference between the light and deep anesthesia

Adaptively Refined Hybrid FDM-RBF Meshless Scheme with Applications to Laminar and Turbulent Viscous Fluid Flows

The focus of this work is to demonstrate a novel approach to true CFD automation based on an adaptive Cartesian point distribution process coupled with a Mesh less flow solution algorithm. As Mesh less method solutions require only an underlying nodal distribution, this approach works well even for complex flow geometries with non-aligned domain boundaries. Through the addition of a so-called shadow layer of body-fitted nodes, application of boundary conditions is simplified considerably, eliminating the stair-casing issues of typical Cartesian-based techniques. This paper describes the approach taken to automatically generate the Mesh less nodal distribution, along with the details of an automatic local refinement process. Also, as the primary interest of this automated CFD solver is for aerospace applications, this work includes the development of standard two-equation turbulence models for use in this Mesh less based solver. Finally, results are shown for several relevant compressible, turbulent flows example configurations, demonstrating the benefits of the automatic refinement as well as the quality of the Mesh less solutions in high-speed flow applications

Two-in-one aortic valve sizing and valvuloplasty conductance balloon catheter

BACKGROUND: Inaccurate aortic valve sizing and selection is linked to paravalvular leakage in transcatheter aortic valve replacement (TAVR). Here, a novel sizing valvuloplasty conductance balloon (SVCB) catheter is shown to be accurate, reproducible, unbiased, and provides real-time tool for aortic valve sizing that fits within the standard valvuloplasty procedure. METHODS AND RESULTS: The SVCB catheter is a valvuloplasty device that uses real-time electrical conductance measurements based on Ohm's Law to size the balloon opposed against the aortic valve at any given inflation pressure. Accuracy and repeatability of the SVCB catheter was performed on the bench in phantoms of known dimension and ex vivo in three domestic swine aortic annuli with comparison to computed tomography (CT) and dilator measurements. Procedural workflow and safety was demonstrated in vivo in three additional domestic swine. SVCB catheter measurements had negligible bias or error for bench accuracy considered as the gold standard (Bias: -0.11 ± 0.26 mm; Error: 1.2%), but greater disagreement in ex vivo versus dilators (Bias: -0.3 ± 1.1 mm; Error: 4.5%), and ex vivo versus CT (Bias: -1.0 ± 1.6 mm; Error: 8.7%). The dilator versus CT accuracy showed similar agreement (Bias: -0.9 ± 1.5 mm; Error: 7.3%). Repeatability was excellent on the bench (Bias: 0.02 ± 0.12 mm; Error: 0.5%) and ex vivo (Bias: -0.4 ± 0.9 mm; Error: 4.6%). In animal studies, the device fit well within the procedural workflow with no adverse events or complications. CONCLUSIONS: Due to the clinical relevance of this accurate, repeatable, unbiased, and real-time sizing measurement, the SVCB catheter may provide a useful tool prior to TAVR. These findings merit a future human study

Design and development of a magnetically-driven ventricular assist device (MVAD): in vitro implementation in the fontan circulation

A rapidly testable novel Magnetically-Driven Ventricular Assist Device (MVAD) with no m ving parts that can be used to provide assistance to the cardiovascular circulation while reducing caval pressure in patients who have undergone the Fontan procedure to palliate the Hypoplastic Left Heart Syndrome (HLHS) is proposed and studied. A benchtop Mock Flow Loop (MFL) of the cardiovascular circulation with a Fontan total cavopulmonary connection (TCPC) is configured to validate this hypothesis. The MFL is based on a Lumped-Parameter Model (LPM) comprised of upper and lower systemic circulation as well as left and right pulmonary circulation compartments. Needle valves are used to accurately replicate vascular resistance (R) while compliance chambers are used to mimic vascular compliance (C). The MFL centerpiece is the truncated aortic arch with an implanted MVAD. A ferro-fluid solution is mixed in water to simulate magnetically-charged blood. The pulsating flow is induced by drawing the ferro-fluid from a main reservoir with a Harvard Apparatus Medical pump while the MVAD provides assistive momentum to the TCPC. Flow and pressure sensor data at specific points in the MFL are acquired via a National Instruments multichannel data acquisition board and processed using LabView. Different prototypes of the MVAD are tested to validate the hypothesis

Using machine learning to characterize heart failure across the scales

Heart failure is a progressive chronic condition in which the heart undergoes detrimental changes in structure and function across multiple scales in time and space. Multiscale models of cardiac growth can provide a patient-specific window into the progression of heart failure and guide personalized treatment planning. Yet, the predictive potential of cardiac growth models remains poorly understood. Here, we quantify predictive power of a stretch-driven growth model using a chronic porcine heart failure model, subject-specific multiscale simulation, and machine learning techniques. We combine hierarchical modeling, Bayesian inference, and Gaussian process regression to quantify the uncertainty of our experimental measurements during an 8-week long study of volume overload in six pigs. We then propagate the experimental uncertainties from the organ scale through our computational growth model and quantify the agreement between experimentally measured and computationally predicted alterations on the cellular scale. Our study suggests that stretch is the major stimulus for myocyte lengthening and demonstrates that a stretch-driven growth model alone can explain 52.7% of the observed changes in myocyte morphology. We anticipate that our approach will allow us to design, calibrate, and validate a new generation of multiscale cardiac growth models to explore the interplay of various subcellular-, cellular-, and organ-level contributors to heart failure. Using machine learning in heart failure research has the potential to combine information from different sources, subjects, and scales to provide a more holistic picture of the failing heart and point toward new treatment strategies

Growing and laying performance of two different-plumage color Japanese quail varieties supplemented with corn silk in their diet

The current study aimed to investigate the dietary supplementation effect of corn silk (CS) on performance and blood chemistry of brown and whitefeathered quails during the grower and layer periods. Japanese quails of brown and white-feathered color (180 birds/variety at 2 wks old) were randomly allotted into three groups with 3 replicates each (n = 20 birds/ replicate). Corn silk powder (CS) was supplemented to the basal diet at 0, 1, and 2% of the diet for each quail variety for 1-month growing period, then continued for another 6-wk laying period to assess the egg production and egg quality characteristics. CS supplementation at 1% and 2% for brown and white-feathered quails respectively improved their growth performance (body weight and weight gain), carcass yield, and intestinal villi length with increasing feed consumption but without changes in feed conversion ratio. In both quail varieties, CS addition had a hypolipidemic effect, confirmed by lowering serum triglyceride (TG), cholesterol (CHO), and low density lipoprotein (LDL) while increased high density lipoprotein (HDL) concentrations (P &lt; 0.05) with a clear response observed in white quails than the brown ones. Besides, CS supplementation increased (P = 0.002) hen day egg production in brown feathered quails, while reducing it in the white-feathered quails compared with the CS-free diet. The increased egg production was not significantly (P &gt; 0.05) correlated with lower content of TG and CHO, while significantly increased the antioxidant content in both quail varieties (P &lt; 0.05). Moreover, CS dietary supplementation significantly enhanced (P = 0.003) the yolk color, especially in brown-feathered quail. In conclusion, CS can be safely supplemented to the Japanese quail diet (1% and 2% for brown-feathered and white-feathered quails respectively) to improve growth performance, and egg quality characteristics

Comparison of four mathematical models to analyze indicator-dilution curves in the coronary circulation

While several models have proven to result in accurate estimations when measuring cardiac output using indicator dilution, the mono-exponential model has primarily been chosen for deriving coronary blood/plasma volume. In this study, we compared four models to derive coronary plasma volume using indicator dilution; the mono-exponential, power-law, gamma-variate, and local density random walk (LDRW) model. In anesthetized goats (N = 14), we determined the distribution volume of high molecular weight (2,000 kDa) dextrans. A bolus injection (1.0 ml, 0.65 mg/ml) was given intracoronary and coronary venous blood samples were taken every 0.5–1.0 s; outflow curves were analyzed using the four aforementioned models. Measurements were done at baseline and during adenosine infusion. Absolute coronary plasma volume estimates varied by ~25% between models, while the relative volume increase during adenosine infusion was similar for all models. The gamma-variate, LDRW, and mono-exponential model resulted in volumes corresponding with literature, whereas the power-model seemed to overestimate the coronary plasma volume. The gamma-variate and LDRW model appear to be suitable alternative models to the mono-exponential model to analyze coronary indicator-dilution curves, particularly since these models are minimally influenced by outliers and do not depend on data of the descending slope of the curve only