Amelioration of behavioural toxicity of aluminium by oligomeric silicic acid and humic acid

ABSTRACT Despite its limited solubility at neutral pH, aluminium is significantly accumulated by the freshwater snail Lymnaea stagnalis, leading to behavioral toxicity. Both organic (humic acid) and non-organic (oligomeric silicic acid) ligands have been shown to reduce Al accumulation probably owing to their binding affinity for Al. This study examined the effect of these ligands on behavioral responses to Al over a 30-day exposure period. Both behavioral state score (a measure of general activity) and feeding behaviors were initially (days 2-4) depressed in the presence of 500 µgl -1 added Al, followed by apparent tolerance (days 8-16) and subsequent depression (day 30). In the presence of either oligomeric Si (molar ratio Al:Si 1:40) or humic acid (10 mgl -1 ) behavioral responses to Al were completely abolished. Neither ligand alone had any effect on behavior except for a slight increase in biting activity in the presence of humic acid on days 2 -4. These results suggest that the presence of complexing ligands may affect toxicity of Al in the natural environment at neutral pH

Kinetics of Surfactant Adsorption at Fluid-Fluid Interfaces: Surfactant Mixtures

The adsorption at the interface between an aqueous solution of several surface-active agents and another fluid (air or oil) phase is addressed theoretically. We derive the kinetic equations from a variation of the interfacial free energy, solve them numerically and provide an analytic solution for the simple case of a linear adsorption isotherm. Calculating asymptotic solutions analytically, we find the characteristic time scales of the adsorption process and observe the behavior of the system at various temporal stages. In particular, we relate the kinetic behavior of the mixture to the properties of its individual constituents and find good agreement with experiments. In the case of kinetically limited adsorption, the mixture kinetics is found to be considerably different from that of the single-surfactant solutions because of strong coupling between the species.Comment: 19 pages, 7 figures, to be published in Langmui

Hospital Preparedness for Critical Care during COVID-19 Pandemic: Exploratory Cross-sectional Study

AIM: The researchers conducted the study to assess intensive care units (ICUs) preparedness in Cairo University Hospitals to deal efficiently and effectively with COVID-19 upcoming waves. METHODS: An exploratory cross-sectional study was conducted at Cairo University Intensive Care Units 6 pediatric ICUs, and 2 adult ICUs in the period from the end of February to the first week of March, 2020; almost 2 weeks after the appearance of the first case of COVID-19 in Egypt by hand-delivered questionnaire method with one of the ICU staff members who were available and have time to take part in the study. WHO checklist for hospital readiness was used; this checklist based on current knowledge and available evidence on the COVID-19 pandemic for WHO’s Regional Office for the Eastern Mediterranean Region. The WHO has developed the checklist to help hospital managers prepare for COVID-19 patient management by optimizing each hospital’s capacities. The list composed of 10 key components: (1) Leadership and coordination; (2) operational support, logistics and supply management; (3) information; (4) communication; (5) human resources; (6) continuity of essential services and surge capacity; (7) rapid identification; (8) diagnosis; (9) isolation and case management; and (10) infection prevention and control. RESULTS: The overall preparedness in both pediatric and adult ICUs was 54%. Overall, adult ICUs were more prepared than pediatric ICUs, especially in communication; continuity of essential services and surge capacity; rapid identification; diagnosis; isolation; and case management. Both of them were comparable regarding operational support, logistics and supply management; human resources; and infection prevention and control, while information component was lower in both types but reached critical values 10% in adult ones. CONCLUSION: The current study demonstrated the intermediate readiness of ICUs at initial outbreak; further assessment during different phases of pandemic is required. Continues education of HCWs and active communication should be established

Weibull-Linear Exponential Distribution and Its Applications

In this article, a new four-parameter lifetime distribution, namely, the Weibull-Linear exponential distribution is defined and studied. Several of its structural properties such as quartiles, moments, mean waiting time, mean residual lifetime, Renyi entropy, mode, and order statistics are derived. Based on the idea of the Weibull T − X family, the new density function of this model is developed. The model parameters, as well as some of the lifetime parameters (reliability and failure rate functions), are estimated using the maximum likelihood method. Asymptotic confidence intervals estimates of the model parameters are also evaluated by using the Fisher information matrix. Moreover, to construct the asymptotic confidence intervals of the reliability and failure rate functions, we need to find their variance of them, which are approximated by the delta method. A real data set is used to illustrate the application of the Weibull-Linear Exponential distribution

Patient-specific air puff-induced loading using machine learning

Introduction: The air puff test is a contactless tonometry test used to measure the intraocular pressure and the cornea’s biomechanical properties. Limitations that most challenge the accuracy of the estimation of the corneal material and the intraocular pressure are the strong intercorrelation between the intraocular pressure and the corneal parameters, either the material properties that can change from one person to another because of age or the geometry parameters like central corneal thickness. This influence produces inaccuracies in the corneal deformation parameters while extracting the IOP parametric equation, which can be reduced through the consideration of the patient-specific air puff pressure distribution taking into account the changes in corneal parameters. This air puff pressure loading distribution can be determined precisely from the fluid-structure interaction (FSI) coupling between the air puff and the eye model. However, the computational fluid dynamics simulation of the air puff in the coupling algorithm is a time-consuming model that is impractical to use in clinical practice and large parametric studies. Methods: By using a supervised machine learning algorithm, we predict the time-dependent air puff pressure distribution for different corneal parameters via a parametric study of the corneal deformations and the gradient boosting algorithm. Results: The results confirmed that the algorithm gives the time-dependent air puff pressure distribution with an MAE of 0.0258, an RMSE of 0.0673, and an execution time of 93 s, which is then applied to the finite element model of the eye generating the corresponding corneal deformations taking into account the FSI influence. Using corneal deformations, the response parameters can be extracted and used to produce more accurate algorithms of the intraocular pressure and corneal material stress-strain index (SSI). Discussion: Estimating the distribution of air pressure on the cornea is essential to increase the accuracy of intraocular pressure (IOP) measurements, which serve as valuable indicator of corneal disease. We find that the air puff pressure loading is largely influenced by complex changes in corneal parameters unique to each patient case. With our innovative algorithm, we can preserve the same accuracy developed by the CFD-based FSI model, while reducing the computational time from approximately 101000 s (28 h) to 720 s (12 min), which is about 99.2% reduction in time. This huge improvement in computational cost will lead to significant improvement in the parametric equations for IOP and the Stress-Strain Index (SSI)

Impact of Silver Nanoparticles on Gene Expression in Aspergillus Flavus Producer Aflatoxin B1

AIM: In this study, we evaluated the effect of silver nanoparticles (AgNPs) on the production of aflatoxin B1 (AFB1) through assessment the transcription activity of aflatoxin biosynthesis pathway genes in Aspergillus flavus ATCC28542.MATERIAL AND METHODS: The mRNAs were quantitative by Real Time-polymerase chain reaction (qRT-PCR) of A. flavus grown in yeast extract sucrose (YES) medium containing AgNPs. Specific primers that are involved in the AFB1 biosynthesis which highly specific to A. flavus, O-methyltransferase gene (omt-A), were designed and used to detect the fungus activity by quantitative PCR assay. The AFB1 production (from A. flavus growth) which effected by AgNPs were measured in YES medium by high-pressure liquid chromatography (HPLC).RESULTS: The AFB1 produced by A. flavus have the highest reduction with 1.5 mg -100 ml of AgNPs were added in media those records 88.2%, 67.7% and 83.5% reduction by using AgNP HA1N, AgNP HA2N and AgNP EH, respectively. While on mycelial growth give significantly inhibitory effect. These results have been confirmed by qRT-PCR which showed that culture of A. flavus with the presence of AgNPs reduced the expression levels of omt-A gene.CONCLUSION: Based on the results of the present study, AgNPs inhibit growth and AFB1 produced by Aspergillus flavus ATCC28542. This was confirmed through RT-PCR approach showing the effect of AgNPs on omt-A gene involved in aflatoxin biosynthesis

EAR RECOGNITION AND OCCLUSION

ABSTRACT Personal identification using 2D ear images still has many problems such as occlusion mostly caused by hair, earrings, and clothes. To avoid this problem, we propose to divide the ear image into non-overlapping equal divisions and identify persons through these non-occluded parts separately and then combine outputs of the classification of these parts in abstract, rank, and measurement level fusion. Experimental results show that the increasing of recognition rate through combining small parts of non-occluded divisions of ear image

siRNA blocking of mammalian target of rapamycin (mTOR) attenuates pathology in annonacin-induced tauopathy in mice

Tauopathy is a pathological hallmark of many neurodegenerative diseases. It is characterized by abnormal aggregates of pathological phosphotau and somatodendritic redistribution. One suggested strategy for treating tauopathy is to stimulate autophagy, hence, getting rid of these pathological protein aggregates. One key controller of autophagy is mTOR. Since stimulation of mTOR leads to inhibition of autophagy, inhibitors of mTOR will cause stimulation of autophagy process. In this report, tauopathy was induced in mice using annonacin. Blocking of mTOR was achieved through stereotaxic injection of siRNA against mTOR. The behavioral and immunohistochemical evaluation revealed the development of tauopathy model as proven by deterioration of behavioral performance in open field test and significant tau aggregates in annonacin-treated mice. Blocking of mTOR revealed significant clearance of tau aggregates in the injected side; however, tau expression was not affected by mTOR blockage

FOXRED1 silencing in mice: a possible animal model for leigh syndrome.

Leigh syndrome (LS) is one of the most puzzling mitochondrial disorders, which is also known as subacute necrotizing encephalopathy. It has an incidence of 1 in 77,000 live births worldwide with poor prognosis. Currently, there is a poor understanding of the underlying pathophysiological mechanisms of the disease without any available effective treatment. Hence, the inevitability for developing suitable animal and cellular models needed for the development of successful new therapeutic modalities. In this short report, we blocked FOXRED1 gene with small interfering RNA (siRNA) using C57bl/6 mice. Results showed neurobehavioral changes in the injected mice along with parallel degeneration in corpus striatum and sparing of the substantia nigra similar to what happen in Leigh syndrome cases. FOXRED1 blockage could serve as a new animal model for Leigh syndrome due to defective CI, which echoes damage to corpus striatum and affection of the central dopaminergic system in this disease. Further preclinical studies are required to validate this model

Plastic use for food and drinks and related knowledge, attitudes, and practices among a sample of Egyptians

IntroductionPlastic is extensively used in everyday life, particularly for food and beverage containers. The inappropriate use of these containers may lead to the leaching of various chemicals from plastic, such as bisphenol A, phthalate, and styrene, which cause numerous adverse health effects. This study aimed to assess the knowledge, attitudes, and practices toward using plastic for food and drinks among a sample of the Egyptian population.Materials and methodsA questionnaire was designed based on scientific literature to assess sociodemographic data, knowledge, attitudes, and practices toward the use of plastic for food and drinks. A total of 639 participants were recruited by employing the convenience sampling technique.ResultsMore than half of the participants (347, 54%) had poor knowledge scores. Personal experiences, social media, and web pages represented the most common knowledge sources. A comparison between plastic-related knowledge scores and the studied sociodemographic characteristics revealed statistically significant differences in age, gender, education, marital status, residence, working, and socioeconomic standard. A good attitude was reported by the majority (515, 80.6%) of participants. The majority (493, 77.2%) were occasional and frequent plastic users and the practice scores were significantly associated with age, education, residence, and socioeconomic standard. Higher educational level, gender (women), and rural residence were predictors of good participants knowledge, while lower socioeconomic status and urban residence were predictors of bad participants practice in a multivariate logistic regression analysis.ConclusionThe observed unsatisfactory knowledge and practice scores vs. the high attitude indicates a knowledge gap that can help direct future improvements. We call for public awareness programs about safe plastic use and the related health hazards of plastic chemicals. We also stress upon the urgent need for a collaboration between health authorities and the plastic and food industry to guarantee that information about proper plastic use is conveyed to consumers