Application of PDMS-based coating in drug delivery systems using PVP as channeling agent

PDMS derivatives have been extensively used as coating in controlled drug delivery systems in pharmaceutical area. The major advantages of these materials are facilitation of adjustment of desired drug release patterns, improvement of film formation and storage stability. In this study PDMS-based coating systems were designed and applied to acetaminophen tablets and their release was investigated from the PDMS-coated tablet dosage form as a drug model. Thus, a water emulsion of PDMS containing tetraethoxysilane as cross-linking agent and polyvinylpyrrolidone (PVP) as channeling agent was prepared. Then, a uniform smooth thin coating of PDMS was applied on acetaminophen tablets and in vitro acetaminophen release from PDMS-coated tablets was carried out with a homemade setup. The morphology of the coated surfaces was studied by SEM technique. The effect of PVP on the mechanical properties of PDMS film was investigated by dynamic mechanical analysis. It was found that, PVP increased the mechanical properties of PDMS. Compounding of polyethylene glycol (PEG) with PVP (1:1) as channeling agents was also studied and compared with PVPs-containing samples. Despite more channeling agent content in PEG–PVP samples, the drug release percentage was decreased.     

Classification of normal/abnormal PCG recordings using a time–frequency approach

The early and accurate diagnosis of cardiovascular diseases (CVDs) are of great importance as they allow early and proper medical treatment and therefore result in reducing the chance of the CVDs being developed to an acute level. In medical procedures, the first step in examining the cardiovascular function is the auscultation of the heart. However, the correct medical diagnosis based on the heart sounds through a stethoscope requires a lot of expertise and, in some cases, needs referral of the patient to a cardiologist. This is not only time-consuming but also imposes a financial burden on the medical system. Thus, automated detection and analysis of the recorded heart sound auscultation has received a lot of attentions in recent years. This study presents a new time–frequency (T–F) based approach for classifying phonocardiogram (PCG) signals into normal and abnormal. In the proposed methodology, each PCG recording is first segmented into the 4 fundamental heart cycles, i.e. S1, systole, S2, and diastole. From each state, a set of T–F features are extracted with the aim of identifying their characteristics in the T–F domain. The features are then applied to a support vector machine to classify the PCG signal into normal or abnormal. The performance of the proposed method is evaluated using the 2016 PhysioNet challenge database and compared with that of the best performing existing methods. The experimental results using tenfold cross-validation show that the proposed method outperforms the existing methods in terms of sensitivity, specificity, and accuracy.

     

Antioxidant activity of protein hydrolysates and purified peptides from Zizyphus jujuba fruits

In recent years, there has been a considerable interest in bioactive peptides derived from food proteins which might have beneficial effects on human health. Zizyphus jujuba is a medicinal plant with well-demonstrated biological functions for which various bioactive compounds except antioxidant peptides have been reported. Therefore, the aim of this study was to determine the antioxidant activity of Z. jujuba-derived protein hydrolysates and the purified peptides. Based upon this study, it was revealed that the hydrolysates prepared from Z. jujuba fruit possessed antioxidant effects. Among the prepared hydrolysates, trypsin hydrolysate with the highest antioxidant activity was fractionated using reverse-phase high-performance liquid chromatography (RP-HPLC). The most potent antioxidant peptides, named fractions F3 and F6, identified as VGQHTR (MW: 678.36 ± 0.3 Da) and GWLK (MW: 482.27 ± 0.3 Da), respectively, using tandem mass spectrometry. This study demonstrated that the derived hydrolysates and the purified peptides from Z. jujuba proteins can prevent oxidative reactions and might be underutilised for food preservation and medicinal purposes. However, more detailed studies are required to explore their antioxidant abilities in vivo.     

Hydrogen gas sensing properties of microwave-assisted 2D Hybrid Pd/rGO: Effect of temperature,humidity and UV illumination

A novel microwave assisted two-dimensional (2D) hybrid material based on nanostructured reduced graphene oxide (rGO) doped with Pd nanoparticles (Pd/rGO) has been synthesised to investigate its hydrogen sensing performance at different operational conditions. The sensing performance has been evaluated at various operating temperatures (room temperature up to 120 °C), hydrogen concentrations (up to 1%), and relative humidity (up to ~44%). The material characterization of the hybrid Pd/rGO analysed by different techniques which confirms homogeneous distribution of Pd NPs (<35 nm) on the multi-layered porous structure of the rGO nanosheets (NSs) and forming the hybrid Pd/rGO NSs. Moreover, the fundamental hydrogen sensing mechanism as well as recovery enhancement by ultraviolet (UV) light are investigated. This work offers an environmentally friendly and energy-saving synthesis approach for hydrogen sensing with excellent control over experimental parameters which can lead to fabrication of a highly selective and sensitive hydrogen sensor.     

Follow-up of 28 horses with third metacarpal unicortical stress fractures following treatment with osteostixis

The results of 31 intracortical dorsal metacarpal stress fractures in 28 horses following unicortical osteostixis were reviewed. The incidence was predominately in the middle third of the lateral aspect of the left metacarpus, and males were affected more commonly. Approximately half of the surgical procedures were performed with the horse in the standing position. The mean times to return to training and racing were 4.25 and 6.9 months respectively. There was no correlation between time taken to return to racing and position of surgery. Complications experienced included lack of suture removal and one case with a seroma.     

A facile and cost-effective method for simultaneous preparation of lectin and tyrosinase from edible mushroom

Agaricus bisporus is a safe and rich source of tyrosinase and lectin. To address the increasing demand for these proteins, a facile method was developed for their simultaneous preparation from A. bisporus. The method includes demelanization of the raw extract followed by stepwise precipitation of the proteins from the aqueous extract. Employing the right organic solvent in demelanization and precipitation steps reduces the intermolecular interactions between these proteins. This enhances the efficacy of gel-permeation chromatography and results in preparation of partially purified lectin and tyrosinase suitable for many applications in biotechnology and bio-research. The method can be performed without diafiltration.     

Industrial–organizational psychology: "Open thy ears O house of Israel."

Explores the relationship between industrial–organizational psychology and common sense from several approaches. First, literature is reviewed pertaining to the inherent problems of developing a science of human behavior in the context of commonly held beliefs about the subject. Second, the results of a study are presented that indicate that 359 nonpsychologists (college students and managerial groups) were able to intuit the findings of recent research in industrial–organizational psychology and, therefore, that at least a portion of this discipline is commonsensical. Finally, it is suggested that the commonsense character of the discipline may be traced to matters about which psychologists have received repeated warnings in the past. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Nanostructured Architectures for Biomolecular Detection inside and outside the Cell

Nanostructured materials can now be engineered with great precision and complexity as a result of advances in design and fabrication, and offer distinct advantages in many biosensing and biomedical applications. The materials most widely used in this field are semiconductors and noble metals. Each offers multiple length scales of nanostructuring that program their physicochemical properties for different biosensing applications. Here, nanostructured materials and their applications are reviewed together with semiconductors and noble metals, as well as hybrid materials that unite these two classes—all with the goal of linking performance characteristics to applications in biomedicine.