The Effectiveness of Probiotics against Viral Infections: A Rapid Review with Focus on SARS-CoV-2 Infection

Viral infections have gained great attention following the rapid emergence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic around the globe. Even with the continuous research on developing vaccines and antiviral agents against various viral infections, no specific treatment or vaccine has been approved for many enteric or respiratory viral infections; in addition, the efficiency of currently available treatments is still limited. One of the most reliable and recommended strategies to control viral infections is prevention. Recently, intense studies are focusing on a promising approach for treating/preventing various viral infections using probiotics. As per the World Health Organization (WHO), probiotics can be defined as “live microorganisms which, when administered in adequate amount, confer a health benefit to the host.” The use of probiotics is a simple, cost-effective, and safe strategy to prevent viral infections, specifically; respiratory tract and intestinal ones, by different means such as stimulating the host’s immune response or modulating gut microbiota. In this rapid review, we emphasize the protective effects of probiotics against viral infections and proposed mechanisms for protection that might offer a novel and cost-effective treatment against current and newly discovered viruses like SARS-CoV-2

Effect of Streptococcus thermophilus supernatant and inulin on Listeria monocytogenes in soft cheese

The antilisterial activity of 0.1, 0.5 and 1 ml of both Streptococcus thermophilus supernatant ( as derived probiotics) and inulin (as prebiotics)  in soft  cheese for three co-incubation periods (24,48 and 72 h) was evaluated. The results showed that the supernatant of S. thermophilus inhibited growth of Listeria monocytogenes at all co-incubation periods, especially when used 1 ml of supernatant ( 3 log reduction at 24 h and 2 log reduction at 48 and 72 h) compared with control (L. monocytogenes only). The S. thermophilus supernatant at 0.5 and 1 ml  was  more effective in reducing growth of L. monocytogenes compared with 0.1 ml of supernatant. No inhibition activity of inulin against L. monocytogenes was observed at all co-incubation periods. These results indicate that S. thermophilus supernatant  has a protective action against L. monocytogenes in soft cheese. Keywords: Streptococcus thermophilus, Listeria monocytogenes, Antilisterial activity, Inulin, Soft cheese

Effect of Hot Chair Strategy on the Acquisition of Second-Grade Middle Class Students

The purpose of the research was to identify the impact of the hot chair strategy on the acquisition of second grade intermediate students of the concepts and the development of the chemical survey and their higher thinking skills. The researchers adopted the experimental design of the two equal groups. The research community determines the average second grade students in the secondary schools in Tikrit for the academic year 2018 -2019, a high school was chosen for girls as a sample. Of a total of 69 students, 34 of the experimental group studied in accordance with the hot chair strategy and 35 students in control group studied the usual way. The researchers compared the two groups in the variables: grades of chemistry for the past year, age calculated by months, academic achievement of the parents of the students, degree of the chemical survey and higher thinking skills. The results showed that there was a superior difference between the students of the experimental group who studied according to the hot chair strategy on the female students of the control group, which studied according to the usual method.El propósito de la investigación fue identificar el impacto de la estrategia de la silla caliente en la adquisición de los estudiantes de segundo grado de los conceptos intermedios y el desarrollo de la encuesta química y sus habilidades de pensamiento superior. Los investigadores adoptaron el diseño experimental de dos grupos iguales. La comunidad investigadora determina el promedio de estudiantes de segundo grado en las escuelas secundarias de Tikrit para el año académico 2018-2019, se eligió una escuela secundaria para niñas como muestra para la investigación. De un total de 69 estudiantes, 34 del grupo experimental estudiaron de acuerdo con la estrategia de la silla caliente y 35 de ellos formaron el grupo de control que estudiaron de la manera habitual. Los investigadores compararon los dos grupos en las variables: grado de química del año pasado, edad calculada por meses, rendimiento académico de los padres de los estudiantes, grado de la encuesta química y habilidades de pensamiento superior. Los resultados mostraron que hubo una diferencia superior entre las estudiantes del grupo experimenta que estudiaron de acuerdo con la estrategia de la silla caliente con respecto a las estudiantes del grupo de control, que estudiaron de acuerdo con el método habitual

Silent hyperlipidaemia modulated vascular endothelial markers

The aetiology of ischemic heart diseases is mainly based on atherosclerosis of coronary artery. Inflammation and oxidative reactions are initiating and aggravating the illness resulting in pathological remodelling of vasculaturze at site of injury. Endothelium lining of blood vessels participated in the reaction biochemically through releasing some proteins into circulatory system which further complicate the condition. The aim of this study was to determine early diagnosed hyperlipidaemia-associated changes of the plasma level of some of these endothelial biomolecules. Compared to healthy control, hyperlipidaemic patients have significantly increased arginase, metalloendopeptidase, peroxidase, myeloperoxidase, and peroxynitrite with concomitant reduction in arylesterase and nitric oxide. The present study concluded that hyperlipidaemia play a great role in modulation of certain plasma protein markers which might be directly related to patient pathological condition or could be used as a tool for diagnosis or patient follow up indicating the stage of vasculature remodelling, healing, inflammation or resolution

Bi-directional block is superior to non-inducibility in predicting freedom from atrial fibrillation after pulmonary vein isolation

Background: There is variability in the endpoints used with the different approaches to pulmonary vein (PV) isolation. Elimination of PVP recorded inside the targeted PV antrum indicates inlet block and is considered the 1st indicator of a successful PV isolation, however this may not be sufficient to predict non recurrence of AF. Aim: To compare the efficacy of two end points, pulmonary vein (PV) entrance block with non-inducibility (NI) Vs achieving PV bi-directional (BD) block in terms of freedom of AF after PV isolation (PVI) for paroxysmal/persistent atrial fibrillation (AF). Method: We included 58 consecutive patients (pts) who underwent PVI for symptomatic AF. In all pts, the end point of ablation was abolishing PV potentials (PVP) in the PVs followed by testing for bidirectional block (defined by both loss of PVP and failure to conduct to the LA by pacing at 10 mA and from 10 bipolar pairs of electrodes on a circular catheter positioned at the entrance of the PV) and/or NI of AF (by burst atrial pacing). Results: Bidirectional block was achieved in 40 patients (69%) while Non inducibility was achieved in 36 (58.5%) patients with an overlap of achieving both endpoints in 18 (31%) patients. Over a follow up period of 17 ± 11 months, 34 pts (85%) in group I Vs 22 (62%) in group II were free of AF. Correlation showed significant relation between BD block (OR = 8.07, P = 0.004) Vs NI of AF post-PVI (OR = 2.8, P = 0.095) in predicting freedom from AF at follow up. Conclusion: Achieving BD block improves results and may predict maintenance of sinus rhythm more than NI of AF after PVI. It can be used as an electrophysiological endpoint alternative to or in conjunction with non inducibility in AF ablation procedures

Effect of Lactobacillus salivarius supernatant against growth and biofilm formation of some pathogenic microorganisms

The Inhbititory effect of cocentrated and non-cocentrated supernatant of the probiotic Lactobacillus salivarius against growth of some potential pathogenic microorganisms which included Pseudomonas eruginosa, Klebsiella spp, Escherichia coli and Candida albicans. The results were diffusion assay revealed that concentrated and non-concentrated supernatant had inhitory effect against pathogenic bacteria with inhibition zone renged between 13-17mm while inhibition effect of concentrated supernatant against C.albicans was inhibition zone 8mm. On the other hand, the effect of these suprnatant against biofilm formation of the tested microorganisms was studied. The result showed that the concentrated supernatant had inhibitory effect on biofilm formation for all tested microorganisms with percentage (28-29)% against tested bacteria and (23)% against C.albicans

Experimental and Numerical Evaluation of Mechanically Stabilized Earth Wall with Deformed Steel Bars Embedded in Tire Shred-Sand Mixture

This article presents the experimental and numerical analysis behavior on Mechanically Stabilized Earth Wall (MSE) under applied overburden load performed on the 1.5 m high, 0.9 m width, and 1.2 m length reinforced with deformed steel bars embedded in sand alone and tires shred-sand mixture. The study investigates how deformed bars, strength, and geometry affect the failure mechanism. The top of the wall was laden with additional overburden weight at various stages to explore the pre-failure wall behavior. The horizontal displacements were measured using potentiometers of the wall face and by potentiometers placed at the top of the loading plate. The results of the observations were compared to the analysis results derived from a numerical model created using the Plaxis 3D software. Numerical modeling was also applied to assess the behavior of MSE wall (3D model) on the failure mechanism of the walls. The parameters for the numerical models were derived from independent tests results, which were compared with the experimental observations. A good level of agreement with measurements was confirmed for the 3D model with the experimental data. From the results, it was deduced that at 30 kPa and 40 kPa, the tire shred-sand mixture with reinforcement gave a 36% and 58% reduction in face deflection compared to sand with reinforcement. The difference between numerical and experimental values ranges from 12% to 15%

Experimental and Numerical Evaluation of Mechanically Stabilized Earth Wall with Deformed Steel Bars Embedded in Tire Shred-Sand Mixture

This article presents the experimental and numerical analysis behavior on Mechanically Stabilized Earth Wall (MSE) under applied overburden load performed on the 1.5 m high, 0.9 m width, and 1.2 m length reinforced with deformed steel bars embedded in sand alone and tires shred-sand mixture. The study investigates how deformed bars, strength, and geometry affect the failure mechanism. The top of the wall was laden with additional overburden weight at various stages to explore the pre-failure wall behavior. The horizontal displacements were measured using potentiometers of the wall face and by potentiometers placed at the top of the loading plate. The results of the observations were compared to the analysis results derived from a numerical model created using the Plaxis 3D software. Numerical modeling was also applied to assess the behavior of MSE wall (3D model) on the failure mechanism of the walls. The parameters for the numerical models were derived from independent tests results, which were compared with the experimental observations. A good level of agreement with measurements was confirmed for the 3D model with the experimental data. From the results, it was deduced that at 30 kPa and 40 kPa, the tire shred-sand mixture with reinforcement gave a 36% and 58% reduction in face deflection compared to sand with reinforcement. The difference between numerical and experimental values ranges from 12% to 15%

Unconfined compressive strength prediction of stabilized expansive clay soil using machine learning techniques

This paper evaluates the potential of machine learning techniques, namely, Gaussian Process Regression (GPR) and Support Vector Machine (SVM), for the prediction of unconfined compressive strength (UCS) of expansive clay soil treated with hydrated-lime-activated rice husk ash. A laboratory dataset containing 121 records has been used with input parameters, including hydrated-lime-activated rice husk ash, liquid limit, plastic limit, plastic index, optimum moisture content, clay activity, and maximum dry density. The performances of the GPR and SVM models are assessed using statistical metrics, including the coefficient of determination (R2), mean absolute error (MAE), root-mean-square error (RMSE), relative rootmean-square error (RRMSE), and performance indicator (ρ). The analysis of the R2 together with MAE, RMSE, RRMSE, and ρ values for the UCS demonstrates that the SVM and GPR models achieved better prediction results, i.e., R2 0.9998, MAE 0.0514, RMSE 0.1408, and ρ 0.0004 and R2 0.9998,MAE 0.3430, RMSE 0.4455, and ρ 0.0011, respectively, as compared to the artificial neural network model recently developed in the literature with (R2 0.9900, MAE 0.3500, RMSE 4.9300, RRMSE 0.2000, and ρ 0.1000) in test phase, which indicates that both models are efficient and reliable for practical applications. Furthermore, the sensitivity analysis result shows that maximum dry density was the key parameter affecting the UCS