Oil Red O based method for Exosome Labelling and Detection

With the realization of the role of exosomes in diseases especially cancer, exosome research is gaining popularity in biomedical sciences. To understand exosome biology, their labelling and tracking studies are important. New and improved methods of exosome labelling for detection and tracking of exosomes need to be developed to harness their therapeutic and diagnostic potential. In this paper, we report a novel, simple and effective method of labelling and detecting exosomes using Oil red O (ORO) which is a dye commonly used for lipid staining. Using ORO is a cost effective and easy approach with intense red colouration of stained exosomes. Further, the issues faced with commonly used lipophilic dyes for exosomes labelling such as long term persistence of dyes, aggregation and micelle formation of dyes, difficulty to distinguish dye particles from labelled exosomes and detection of large aggregates of dye or dye-exosome are not seen with ORO dye. This method shows good labelling efficiency of exosomes with very sensitive detection and real-time tracking of the cellular uptake of exosomes.

Comparison of methods to estimate the size of Indian pangolin (Manis crassicaudata) scale seizures using species-specific conversion parameters

The absence of robust species-specific methods to estimate the number of animals in seizures of pangolin scales is a major barrier to effective law enforcement. Therefore, studies focused on developing methods to establish accurate conversion parameters are a priority. This study proposes improved methods to estimate the number of pangolins in the illegal trade to inform law-enforcing authorities. Based on the observations of 25 specimens, Indian pangolins were on average found to possess 511 scales. Three morph-types of scales were identified: broad rhombic (n=411), elongated kite shape (n=69), and folded scales (n=31). The mean dry weight of the three-scale morph-types was 7.5 g, 4.9 g, and 6.2 g. Based on the average frequency and mean dry weight of each scale morph type, the species-specific dry weight of scales for Indian pangolins was 3.6 kg. Accordingly, we propose new and improved methods based on scale morph-type frequencies and species-specific dry weight of scales to estimate the number of Indian pangolins from quantities of scales. Their accuracy was compared with current methods, and the improved methods were found to be more accurate.

Review on Strategies and Technologies for Exosome Isolation and Purification

Exosomes, a nano-sized subtype of extracellular vesicles secreted from almost all living cells, are capable of transferring cell-specific constituents of the source cell to the recipient cell. Cumulative evidence has revealed exosomes play an irreplaceable role in prognostic, diagnostic, and even therapeutic aspects. A method that can efficiently provide intact and pure exosomes samples is the first step to both exosome-based liquid biopsies and therapeutics. Unfortunately, common exosomal separation techniques suffer from operation complexity, time consumption, large sample volumes and low purity, posing significant challenges for exosomal downstream analysis. Efficient, simple, and affordable methods to isolate exosomes are crucial to carrying out relevant researches. In the last decade, emerging technologies, especially microfluidic chips, have proposed superior strategies for exosome isolation and exhibited fascinating performances. While many excellent reviews have overviewed various methods, a compressive review including updated/improved methods for exosomal isolation is indispensable. Herein, we first overview exosomal properties, biogenesis, contents, and functions. Then, we briefly outline the conventional technologies and discuss the challenges of clinical applications of these technologies. Finally, we review emerging exosomal isolation strategies and large-scale GMP production of engineered exosomes to open up future perspectives of next-generation Exo-devices for cancer diagnosis and treatment.

[18F]Nifene PET/CT Imaging in Mice: Improved Methods and Preliminary Studies of α4β2* Nicotinic Acetylcholinergic Receptors in Transgenic A53T Mouse Model of α-Synucleinopathy and Post-Mortem Human Parkinson’s Disease

We report [18F]nifene binding to α4β2* nicotinic acetylcholinergic receptors (nAChRs) in Parkinson’s disease (PD). The study used transgenic Hualpha-Syn(A53T) PD mouse model of α-synucleinopathy for PET/CT studies in vivo and autoradiography in vitro. Additionally, postmortem human PD brain sections comprising of anterior cingulate were used in vitro to assess translation to human studies. Because the small size of mice brain poses challenges for PET imaging, improved methods for radiosynthesis of [18F]nifene and simplified PET/CT procedures in mice were developed by comparing intravenous (IV) and intraperitoneal (IP) administered [18F]nifene. An optimal PET/CT imaging time of 30–60 min post injection of [18F]nifene was established to provide thalamus to cerebellum ratio of 2.5 (with IV) and 2 (with IP). Transgenic Hualpha-Syn(A53T) mice brain slices exhibited 20–35% decrease while in vivo a 20–30% decrease of [18F]nifene was observed. Lewy bodies and α-synuclein aggregates were confirmed in human PD brain sections which lowered the [18F]nifene binding by more than 50% in anterior cingulate. Thus [18F]nifene offers a valuable tool for PET imaging studies of PD.

Field Demonstration of Heat Technology to Mitigate Heat Sinks for Drywood Termite (Blattodea: Kalotermitidae) Management

With heat treatments to control drywood termites (Blattodea: Kalotermitidae), the presence of heat sinks causes heat to be distributed unevenly throughout the treatment areas. Drywood termites may move to galleries in heat sink areas to avoid exposure to lethal temperatures. Our studies were conducted in Crytotermes brevis-infested condominiums in Honolulu, Hawaii to reflect real-world condominium scenarios; either a standard heat treatment performed by a heat remediation company or an improved heat treatment was used. For improved treatments, heated air was directed into the toe-kick voids of C. brevis infested cabinets to reduce heat sink effects and increase the heat penetration into these difficult-to-heat areas. Eight thermistor sensors placed inside toe-kick voids, treatment zone, embedded inside cabinets’ sidewalls, and in a wooden cube recorded target temperatures of above 46 °C or 50 °C for 120 minutes. A pretreatment and follow-up inspections were performed at 6 months posttreatment to monitor termite inactivity using visual observations and by recording the numbers of spiked peaks on a microwave technology termite detection device (Termatrac). In improved treatment condominiums, significantly higher numbers of spiked peaks were recorded at pretreatment as compared to 6 months posttreatment. Efficacious heat treatment protocols using the improved methods are proposed.

Sentinel-2 Time Series Analysis for Identification of Underutilized Land in Europe

Biomass and bioenergy play a central role in Europe’s Green Transition. Currently, biomass is representing half of the renewable energy sources used. While the role of renewables in the energy mix is undisputed, there have been many controversial discussions on the use of biomass for energy due to the “food versus fuel” debate. Using previously underutilized lands for bioenergy is one possibility to prevent this discussion. This study supports the attempts to increase biomass for bioenergy through the provision of improved methods to identify underutilized lands in Europe. We employ advanced analysis methods based on time series modelling using Sentinel-2 (S2) data from 2017 to 2019 in order to distinguish utilized from underutilized land in twelve study areas in different bio-geographical regions (BGR) across Europe. The calculated parameters of the computed model function combined with temporal statistics were used to train a random forest classifier (RF). The achieved overall accuracies (OA) per study area vary between 80.25 and 96.76%, with confidence intervals (CI) ranging between 1.77% and 6.28% at a 95% confidence level. All in all, nearly 500,000 ha of underutilized land potentially available for agricultural bioenergy production were identified in this study, with the greatest amount mapped in Eastern Europe.

Fingerprinting/indoor positioning using complex planar splines

The rapid development of various LBS-based applications and services that operate on the basis of the user’s current location, both global GPS and local LBS, today require the development of new and improved methods. This concerns, first of all, methods for determining the local location of LPS users in premises, if there is a high concentration of users and the presence of difficulties in the propagation of radio signals. the use of local methods of location determination based on the fingerprinting method is considered. It is shown that to improve the user positioning accuracy, it is expedient to use a combination of several methods. to determine the local location of the user, a method based on the finite element method and linear complex planar splines is proposed. the construction of linear complex planar splines is considered, their coefficients are found. finding the error in determining the coordinates of the user’s UE location is shown. The use of the proposed method will improve the accuracy of determining the coordinates of the user’s location and will ensure the provision of LBS services and applications to users in the premises under various conditions of their provision.

Gas-stabilizing nanoparticles for ultrasound imaging and therapy of cancer

The use of ultrasound in the clinic has been long established for cancer detection and image-guided tissue biopsies. In addition, ultrasound-based methods have been widely explored to develop more effective cancer therapies such as localized drug delivery, sonodynamic therapy, and focused ultrasound surgery. Stabilized fluorocarbon microbubbles have been in use as contrast agents for ultrasound imaging in the clinic for several decades. It is also known that microbubble cavitation could generate thermal, mechanical, and chemical effects in the tissue to improve ultrasound-based therapies. However, the large size, poor stability, and short-term cavitation activity of microbubbles limit their applications in cancer imaging and therapy. This review will focus on an alternative type of ultrasound responsive material; gas-stabilizing nanoparticles, which can address the limitations of microbubbles with their nanoscale size, robustness, and high cavitation activity. This review will be of interest to researchers who wish to explore new agents to develop improved methods for molecular ultrasound imaging and therapy of cancer.

Modelling of contact and tribotechnical parameters of metal–polymer gears taking into account wear and correction of teeth

The estimation and the analysis of the arising contact pressures and tribotechnical parameters, that is, wear and durability, of metal-polymer spur gears using the author's computational method are presented in this study. Gears with a steel gear and pinion made of polyamide PA6 modified with dispersed carbon fibers (CF) or glass fibers (GF) whose content was 30%, PA6 + 30CF and PA6 + 30GF correspondingly, are studied. This took into account the parity of engagement, the effect of composite pinion teeth wear and gear correction. Quantitative and qualitative regularities of change of the specified parameters depending on composite type and gear correction type are established. It is found that the teeth wear of composite toothed wheels has a significant effect on reducing the values of the initial maximum contact pressures in the engagement. The distribution of linear wear along the teeth working profile and the localization of its maximum values, depending on the correction of engagement, are determined. The minimum durability of metal–polymer gears is calculated by simplified and improved methods. The optimal values of the correction coefficients at which the minimum durability is highest for both combination types of metal–polymer gears with height and angular teeth correction are established. The durability of metal–polymer gears with a driving pinion made of PA6 + 30CF composite calculated with the improved method is about seven times higher than the pinion made of PA6 + 30GF composite. In contrast to the methods of calculation of metal gears known from publications, the method presented in this study takes into account such practically significant factors as change of radii of tooth profile curvature owing to wear, their correction and number of teeth pairs at the engagement. In metal–polymer gears, there are no analytical calculation methods for modelling wear and tribological durability compared with that of the author's method.