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BioRxiv : the Preprint Server For... Jul 2023Reduction of the production of amyloid beta (Aβ) species has been intensively investigated as potential therapeutic approaches for Alzheimer's disease (AD). However,...
Reduction of the production of amyloid beta (Aβ) species has been intensively investigated as potential therapeutic approaches for Alzheimer's disease (AD). However, the degradation of Aβ species, another potential beneficial approach, has been far less explored. In this study, we discovered that ceruloplasmin (CP), an important multi-copper oxidase (MCO) in human blood, could degrade Aβ peptides. We also found that the presence of Vitamin C could enhance the degrading effect in a concentration-dependent manner. We then validated the CP-Aβ interaction using total internal reflection fluorescence (TIRF) microscopy, fluorescence photometer, and fluorescence polarization measurement. Based on the above discovery, we hypothesized that other MCOs had similar Aβ-degrading functions. Indeed, we found that other MCOs could induce Aβ degradation as well. Remarkably, we revealed that ascorbate oxidase (AO) had the strongest degrading effect among the tested MCOs. Using induced pluripotent stem (iPS) neuron cells, we observed that AO could rescue neuron toxicity which induced by Aβ oligomers. In addition, our electrophysiological analysis with brain slices suggested that AO could prevent an Ab-induced deficit in synaptic transmission in the hippocampus. To the best of our knowledge, our report is the first to demonstrate that MCOs have a degrading function for peptides/proteins. Further investigations are warranted to explore the possible benefits of MCOs for future AD treatment.
PubMed: 37461701
DOI: 10.1101/2023.07.02.547398 -
Environment International Aug 2023This study analyzed the variability of equivalent black carbon (eBC) mass concentrations and their sources in urban Europe to provide insights into the use of eBC as an...
This study analyzed the variability of equivalent black carbon (eBC) mass concentrations and their sources in urban Europe to provide insights into the use of eBC as an advanced air quality (AQ) parameter for AQ standards. This study compiled eBC mass concentration datasets covering the period between 2006 and 2022 from 50 measurement stations, including 23 urban background (UB), 18 traffic (TR), 7 suburban (SUB), and 2 regional background (RB) sites. The results highlighted the need for the harmonization of eBC measurements to allow for direct comparisons between eBC mass concentrations measured across urban Europe. The eBC mass concentrations exhibited a decreasing trend as follows: TR > UB > SUB > RB. Furthermore, a clear decreasing trend in eBC concentrations was observed in the UB sites moving from Southern to Northern Europe. The eBC mass concentrations exhibited significant spatiotemporal heterogeneity, including marked differences in eBC mass concentration and variable contributions of pollution sources to bulk eBC between different cities. Seasonal patterns in eBC concentrations were also evident, with higher winter concentrations observed in a large proportion of cities, especially at UB and SUB sites. The contribution of eBC from fossil fuel combustion, mostly traffic (eBC) was higher than that of residential and commercial sources (eBC) in all European sites studied. Nevertheless, eBC still had a substantial contribution to total eBC mass concentrations at a majority of the sites. eBC trend analysis revealed decreasing trends for eBC over the last decade, while eBC remained relatively constant or even increased slightly in some cities.
Topics: Air Pollutants; Environmental Monitoring; Aerosols; Air Pollution; Europe; Seasons; Soot; Carbon; Particulate Matter
PubMed: 37451041
DOI: 10.1016/j.envint.2023.108081 -
Nanomaterials (Basel, Switzerland) Jul 2023ZnO is an effective photocatalyst applied to the degradation of organic dyes in aqueous media. In this study, the UV-light and sunlight-driven photocatalytic activities...
ZnO is an effective photocatalyst applied to the degradation of organic dyes in aqueous media. In this study, the UV-light and sunlight-driven photocatalytic activities of ZnO nanoparticles are evaluated. A handheld Lovibond photometer was purposefully calibrated in order to monitor the dye removal in outdoor conditions. The effect of ZnO defect states, i.e., the presence of zinc and oxygen defects on the photocatalytic activity was probed for two types of dyes: fuchsin and methylene blue. Three morphologies of ZnO nanoparticles were deliberately selected, i.e., spherical, facetted and a mix of spherical and facetted, ascertained via transmission electron microscopy. Aqueous and non-aqueous sol-gel routes were applied to their synthesis in order to tailor their size, morphology and defect states. Raman spectroscopy demonstrated that the spherical nanoparticles contained a high amount of oxygen vacancies and zinc interstitials. Photoluminescence spectroscopy revealed that the facetted nanoparticles harbored zinc vacancies in addition to oxygen vacancies. A mechanism for dye degradation based on the possible surface defects in facetted nanoparticles is proposed in this work. The reusability of these nanoparticles for five cycles of dye degradation was also analyzed. More specifically, facetted ZnO nanoparticles tend to exhibit higher efficiencies and reusability than spherical nanoparticles.
PubMed: 37446514
DOI: 10.3390/nano13131998 -
Biosensors May 2023Excessive use of pesticides could potentially harm the environment for a long time. The reason for this is that the banned pesticide is still likely to be used...
Excessive use of pesticides could potentially harm the environment for a long time. The reason for this is that the banned pesticide is still likely to be used incorrectly. Carbofuran and other banned pesticides that remain in the environment may also have a negative effect on human beings. In order to provide a better chance for effective environmental screening, this thesis describes a prototype of a photometer tested with cholinesterase to potentially detect pesticides in the environment. The open-source portable photodetection platform uses a color-programmable red, green and blue light-emitting diode (RGB LED) as a light source and a TSL230R light frequency sensor. Acetylcholinesterase from (AChE) with high similarity to human AChE was used for biorecognition. The Ellman method was selected as a standard method. Two analytical approaches were applied: (1) subtraction of the output values after a certain period of time and (2) comparison of the slope values of the linear trend. The optimal preincubation time for carbofuran with AChE was 7 min. The limits of detection for carbofuran were 6.3 nmol/L for the kinetic assay and 13.5 nmol/L for the endpoint assay. The paper demonstrates that the open alternative for commercial photometry is equivalent. The concept based on the OS3P/OS3P could be used as a large-scale screening system.
Topics: Humans; Carbofuran; Cholinesterase Inhibitors; Acetylcholinesterase; Pesticides; Cholinesterases
PubMed: 37366964
DOI: 10.3390/bios13060599 -
Animals : An Open Access Journal From... May 2023Artificial insemination in the swine industry, as in other species, demands adequate semen handling and accurate evaluation for the preparation of seminal doses. Sperm...
Artificial insemination in the swine industry, as in other species, demands adequate semen handling and accurate evaluation for the preparation of seminal doses. Sperm concentration and motility estimates are part of the semen evaluation process and are considered important for maximizing the yield of doses for insemination. In this study, methods were examined for their accuracy in the estimation of boar sperm concentration and motility. Assessments of sperm concentration were carried out using iSperm, ISAS v1, Open CASA v2, and the Accuread photometer. Analyses of sperm motility were performed with iSperm, ISAS v1, and Open CASA v2 systems. In this study, boar semen samples were collected from 10 healthy males from two genetic lines. There were no relevant differences between sire lines when sperm concentration was assessed. A Bayesian analysis was applied to the four methods used to assess sperm concentration to examine whether there are relevant differences between them. Results suggested differences in the four methods, with a probability of relevance (PR) of 0.86-1.00. The iSperm method revealed higher concentration values within the highest posterior density region at 95% confidence interval (HPD) = 167.0, 224.2 M/mL, whereas Open CASA v2 showed the lowest values, with HPD = 99.3, 155.9 M/mL. The iSperm demonstrated higher reliability in measuring sperm concentration compared to other methods or devices within the given range of confidence. ANOVAs revealed relevant differences in the three methods of motility estimation. Overall, differences in boar sperm concentration and motility estimates were found using various methods, but further studies are needed for better characterization of these differences.
PubMed: 37238052
DOI: 10.3390/ani13101622 -
RSC Advances Apr 2023The demand for the development of portable and low-cost analytical devices has encouraged studies employing additive manufacturing techniques, such as 3D-printing. This...
The demand for the development of portable and low-cost analytical devices has encouraged studies employing additive manufacturing techniques, such as 3D-printing. This method can be used to produce components such as printed electrodes, photometers, and fluorometers for low-cost systems that provide advantages including low sample volume, reduced chemical waste, and easy coupling with LED-based optics and other instrumental devices. In the present work, a modular 3D-printed fluorometer/photometer was designed and applied for the determination of caffeine (CAF), ciprofloxacin (CIP), and Fe(ii) in pharmaceutical samples. All the plastic parts were printed separately by a 3D printer, using Tritan as the plastic material (black color). The final size of the modular 3D-printed device was 12 × 8 cm. The radiation sources were light-emitting diodes (LEDs), while a light dependent resistor (LDR) was used as a photodetector. The analytical curves obtained for the device were: = 3.00 × 10 [CAF] + 1.00 and = 0.987 for caffeine; = 6.90 × 10 [CIP] - 3.39 × 10 and = 0.991 for ciprofloxacin; and = 1.12 × 10 [Fe(ii)] + 1.26 × 10 and = 0.998 for iron(ii). The results obtained using the developed device were compared with reference methods, with no statistically significant differences observed. The 3D-printed device was composed of moveable parts, providing flexibility for adaptation and application as a photometer or fluorometer, by only switching the photodetector position. The LED could also be easily switched, permitting application of the device for different purposes. The cost of the device, including the printing and electronic components, was lower than US$10. The use of 3D-printing enables the development of portable instruments for use in remote locations with a lack of research resources.
PubMed: 37077256
DOI: 10.1039/d3ra01281f -
Scientific Reports Apr 2023This paper reports on developing a low cost but efficient paired emitter-detector diode (PEDD)-based photometer. The photometer consists of a white light-emitting diode...
This paper reports on developing a low cost but efficient paired emitter-detector diode (PEDD)-based photometer. The photometer consists of a white light-emitting diode (LED) as the emitter diode, an RGB LED as the detector diode, and a multimeter for recoding the signal. The developed PEDD-based photometer was utilized for the determination of liquid bleach adulteration in cow milk samples. N,N-Diethyl-p-phenylenediamine sulfate aqueous solution of pH 6 was used as a probe to monitor the presence of residual active chlorine in milk. The results showed that the developed method could be used to determine sodium hypochlorite in the concentration range of 0.5 to 20.0 ppm Cl with 0.14 and 0.46 ppm Cl limit of detection and limit of quantification, respectively. The intraday and interday precisions of the method at two concentration levels of 5.5 and 13.7 ppm Cl were 1.04% and 0.52%, and 1.81% and 1.02%, respectively. The recoveries of 114.2% and 106.9% were obtained for 5.5 and 13.7 ppm Cl concentrations levels, respectively. Real sample analyzes results showed that "maybe" liquid bleach adulteration in milk is the case for local distributors of raw milk.
Topics: Animals; Milk; Sodium Hypochlorite; Photometry
PubMed: 37069217
DOI: 10.1038/s41598-023-33527-y -
African Journal of Laboratory Medicine 2023Haemolysis - one of the major limiting factors of red cell concentrate quality - must be measured as a quality-monitoring requirement. According to international quality...
BACKGROUND
Haemolysis - one of the major limiting factors of red cell concentrate quality - must be measured as a quality-monitoring requirement. According to international quality standards, percentage haemolysis must be monitored in 1.0% of red cell concentrates produced monthly and maintained under 0.8%.
OBJECTIVE
This study assessed three alternative methods for determining plasma haemoglobin concentration in peripheral blood banks that lack a plasma or low haemoglobin photometer - the gold-standard method - in Sri Lanka.
METHODS
A standard haemolysate was prepared using an unexpired whole blood pack of normal haemoglobin concentration. A concentration series from 0.1 g/dL to 1.0 g/dL was prepared by diluting portions of standard haemolysate with saline. The alternative methods, namely visual haemoglobin colour scale, spectrophotometric calibration graph, and standard haemolysate capillary tube comparison, were designed using this concentration series and were used to test red cell concentrates received at the Quality Control Department of the National Blood Center, Sri Lanka, from February 2021 to May 2021.
RESULTS
A strong correlation was observed between the haemoglobin photometer method and the alternative methods ( = ~0.9). Based on the linear regression model, the standard haemolysate capillary tube comparison method was the best of the three alternative methods ( = 0.974).
CONCLUSION
All three alternative methods are recommended for use in peripheral blood banks. The standard haemolysate capillary tube comparison method was the best model.
PubMed: 36873291
DOI: 10.4102/ajlm.v12i1.1987 -
Optics Express Feb 2023In order to increase the optical path and related sensitivity of photometers, multiple axial-reflection of parallel light-beam inside a capillary cavity is one of the...
In order to increase the optical path and related sensitivity of photometers, multiple axial-reflection of parallel light-beam inside a capillary cavity is one of the most effective ways. However, there is a non-optimum trade-off between optical path and light intensity, e.g., smaller aperture on cavity mirror can increase multiple axial-reflection times (i.e., longer optical path) due to the lower cavity-loss, but it would also reduce coupling efficiency, light intensity, and related signal-to-noise ratio. Herein, an optical beam shaper, which is composed of two optical lenses with an apertured mirror, was proposed to focus the light beam (i.e., increasing coupling efficiency) without deteriorating beam parallelism and related multiple axial-reflection. Thus, by combining the optical beam shaper with a capillary cavity, large optical path enhancement (10-fold of capillary length) and high coupling efficiency (>65%) can be realized simultaneously, where the coupling efficiency was improved 50-fold. An optical beam shaper photometer (with a 7 cm long capillary) was fabricated and applied to detect water in ethanol with a detection limit of 12.5 ppm, which is 800-fold and 32∼80 fold lower than that of the commercial spectrometer (1 cm cuvette) and previous reports, respectively.
PubMed: 36859917
DOI: 10.1364/OE.478937 -
Optics Express Feb 2023Aerosol microphysical properties, such as volume concentration (VC) and effective radius (ER), are of great importance to evaluate their radiative forcing and impacts on...
Aerosol microphysical properties, such as volume concentration (VC) and effective radius (ER), are of great importance to evaluate their radiative forcing and impacts on climate change. However, range-resolved aerosol VC and ER still cannot be obtained by remote sensing currently except for the column-integrated one from sun-photometer observation. In this study, a retrieval method of range-resolved aerosol VC and ER is firstly proposed based on the partial least squares regression (PLSR) and deep neural networks (DNN), combining polarization lidar and collocated AERONET (AErosol RObotic NETwork) sun-photometer observations. The results show that the measurement of widely-used polarization lidar can be reasonably used to derive the aerosol VC and ER, with the determination coefficient (R) of 0.89 (0.77) for VC (ER) by use of the DNN method. Moreover, it is proven that the lidar-based height-resolved VC and ER at near-surface are well consistent with independent observations of collocated Aerodynamic Particle Sizer (APS). Additionally, we found that there are significant diurnal and seasonal variations of aerosol VC and ER in the atmosphere at Semi-Arid Climate and Environment Observatory of Lanzhou University (SACOL). Compared with columnar ones from the sun-photometer observation, this study provides a reliable and practical way to obtain full-day range-resolved aerosol VC and ER from widely-used polarization lidar observation, even under cloud conditions. Moreover, this study also can be applied to long-term observations by current ground-based lidar networks and spaceborne CALIPSO lidar, aiming to further evaluate aerosol climatic effects more accurately.
PubMed: 36859889
DOI: 10.1364/OE.481252