Publications by authors named "Mahmoud Mohamed"

411 Publications

Machine Learning-Based Propped Fracture Conductivity Correlations of Several Shale Formations.

ACS Omega 2021 Jul 16;6(29):18782-18792. Epub 2021 Jul 16.

College of Petroleum Engineering & Geosciences, King Fahd University of Petroleum & Minerals, Dhahran 31261, Saudi Arabia.

In hydraulic fracturing operations, small rounded particles called proppants are mixed and injected with fracture fluids into the targeted formation. The proppant particles hold the fracture open against formation closure stresses, providing a conduit for the reservoir fluid flow. The fracture's capacity to transport fluids is called fracture conductivity and is the product of proppant permeability and fracture width. Prediction of the propped fracture conductivity is essential for fracture design optimization. Several theoretical and few empirical models have been developed in the literature to estimate fracture conductivity, but these models either suffer from complexity, making them impractical, or accuracy due to data limitations. In this research, and for the first time, a machine learning approach was used to generate simple and accurate propped fracture conductivity correlations in unconventional gas shale formations. Around 350 consistent data points were collected from experiments on several important shale formations, namely, Marcellus, Barnett, Fayetteville, and Eagle Ford. Several machine learning models were utilized in this research, such as artificial neural network (ANN), fuzzy logic, and functional network. The ANN model provided the highest accuracy in fracture conductivity estimation with of 0.89 and 0.93 for training and testing data sets, respectively. We observed that a higher accuracy could be achieved by creating a correlation specific for each shale formation individually. Easily obtained input parameters were used to predict the fracture conductivity, namely, fracture orientation, closure stress, proppant mesh size, proppant load, static Young's modulus, static Poisson's ratio, and brittleness index. Exploratory data analysis showed that the features above are important where the closure stress is the most significant.
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http://dx.doi.org/10.1021/acsomega.1c01919DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8319928PMC
July 2021

Ethnoveterinary botanical survey of medicinal plants used in Pashto, Punjabi and Saraiki communities of Southwest Pakistan.

Vet Med Sci 2021 Jul 22. Epub 2021 Jul 22.

Department of Biological Sciences, National University of Medical Sciences, Rawalpindi, Pakistan.

Medicinal plants are highly used in the ethnoveterinary practice as considerable livestock resources in remote areas. The aim of the present study is to explore the ethnoveterinary medicinal practices in three different communities and discuss the cross-cultural consensus on the usage of medicinal plants for the treatment of animals. The field survey was conducted by the animal healers of the area during the different seasons of plant growth. A total of 83 informants were interviewed through Semi-structured interview involving experts of traditional knowledge in 21 localities of the three regions (Zhob, D. I. Khan and Mianwali) were conducted. Findings of the study were quantitatively analyzed through the informant consensus factors to identify the homogeneity information provided by the informants. Furthermore, cross-culture consensuses were analyzed and recorded data were represented in a tabulated and Venn diagrams. In particularly, 59 species of plants were documented in the comparative analysis. Among them, 32 plant species were recorded in Pashto community, while Punjabi and Sarakai communities exhibited nine and four plant species, respectively. Whereas cross-cultural analysis showed 14 medicinal plants that were commonly utilized by three different ethnic communities, that indicated low interregional consensus in regard to ethnoveterinary practices of medicinal plants. The current study showed that different communities and ethnic groups sharing some traditional knowledge and cross-culturally approaches have been reported from traditional uses of plants against livestock's diseases. Therefore, current findings are the opportunities to scrutinize the plants for the discovery of new drug sources for humans and animals.
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http://dx.doi.org/10.1002/vms3.582DOI Listing
July 2021

Fortification of -- (ABT) Fermented Milk with Heat-Treated Industrial Yeast Enhances Its Selected Properties.

Molecules 2021 Jun 25;26(13). Epub 2021 Jun 25.

Department of Botany and Microbiology, Faculty of Science, Cairo University, Giza 12613, Egypt.

The improvement of milk dairy products' quality and nutritional value during shelf-life storage is the ultimate goal of many studies worldwide. Therefore, in the present study, prospective beneficial effects of adding two different industrial yeasts, and pretreated by heating at 85 °C for 10 min to be inactivated, before fermentation on some properties of ABT fermented milk were evaluated. The results of this study showed that the addition of 3% and 5% (/) heat-treated yeasts to the milk enhanced the growth of starter culture, , and , during the fermentation period as well as its viability after 20 days of cold storage at 5 ± 1 °C. Furthermore, levels of lactic and acetic acids were significantly increased from 120.45 ± 0.65 and 457.80 ± 0.70 µg/mL in the control without heat-treated yeast to 145.67 ± 0.77 and 488.32 ± 0.33 µg/mL with 5% supplementation of respectively. Moreover, the addition of heat-treated yeasts to ABT fermented milk enhanced the antioxidant capacity by increasing the efficiency of free radical scavenging as well as the proteolytic activity. Taken together, these results suggest promising application of non-viable industrial yeasts as nutrients in the fermentation process of ABT milk to enhance the growth and viability of ABT starter cultures before and after a 20-day cold storage period by improving the fermented milk level of organic acids, antioxidant capacity, and proteolytic activities.
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http://dx.doi.org/10.3390/molecules26133876DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8271856PMC
June 2021

Chelating Agents Usage in Optimization of Fracturing Fluid Rheology Prepared from Seawater.

Polymers (Basel) 2021 Jun 27;13(13). Epub 2021 Jun 27.

EXPEC ARC, Saudi ARAMCO, Dhahran 31311, Saudi Arabia.

Hydraulic fracturing consumes massive volumes of freshwater that is usually scarce and costly. Such operation is not sustainable, and hence seawater could be used as an alternative. Nevertheless, seawater has high total dissolved solids (TDS), affecting the fracturing fluid rheology and providing a damage potential to the subterranean hydrocarbon reservoirs. Resolving these issues requires fracturing fluid systems with many additives, which results in an expensive and non-eco-friendly system. This study proposes eco-friendly and biodegradable chelating agents that could replace many additives such as scale inhibitors and crosslinkers. The study aims to optimize the rheology of seawater fracturing fluids using a chelating agent and polymer. By optimizing ,-Dicarboxymethyl glutamic acid (GLDA) conditions, high viscosity was achieved using a standard industry rheometer. The GLDA was mixed with carboxymethyl hydroxypropyl guar (CMHPG) polymer and tested in both deionized water (DW) and seawater (SW). The polymer was examined first, where the rheology did not show a time-dependent behavior. The polymer in SW showed a slightly higher viscosity than in DW. The GLDA and CMHPG were tested at different temperatures, pH, and concentrations. These sets showed a time-dependent viscosity behavior, which can be utilized in various fracturing steps. Results showed that the solution pH and GLDA concentration significantly impacted the fluid viscosity magnitude and behavior. The developed formulation is shear thinning, where the viscosity declines as the shear rate increases. The temperature negatively impacted the viscosity and caused the formulation to break. The study provided an understanding of how to optimize the rheology of SW fracturing fluid based on GLDA chelating and CMHPG polymer.
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http://dx.doi.org/10.3390/polym13132111DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8271447PMC
June 2021

Is it safe to receive kidneys from deceased kidney donors tested positive for covid-19 infection?

Ren Fail 2021 12;43(1):1060-1062

Renal Department, University Hospital Coventry & Warwickshire, Renal, Coventry, UK.

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http://dx.doi.org/10.1080/0886022X.2021.1931319DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8253181PMC
December 2021

COVID-19 vaccine induced rhabdomyolysis: Case report with literature review.

Diabetes Metab Syndr 2021 Jun 15;15(4):102170. Epub 2021 Jun 15.

Medicine Department, Icahn School of Medicine at Mount Sinai / NYC Health + Hospitals Queens, New York, USA. Electronic address:

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http://dx.doi.org/10.1016/j.dsx.2021.06.007DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8205294PMC
June 2021

Dicationic Surfactants as an Additive in Fracturing Fluids to Mitigate Clay Swelling: A Petrophysical and Rock Mechanical Assessment.

ACS Omega 2021 Jun 10;6(24):15867-15877. Epub 2021 Jun 10.

Center for Integrative Petroleum Research (CIPR), King Fahd University of Petroleum & Minerals, 31261 Dhahran, Saudi Arabia.

The interactions of clays with freshwater in unconventional tight sandstones can affect the mechanical properties of the rock. The hydraulic fracturing technique is the most successful technique to produce hydrocarbons from unconventional tight sandstone formations. Knowledge of clay minerals and their chemical interactions with fracturing fluids is extremely vital in the optimal design of fracturing fluids. In this study, quaternary ammonium-based dicationic surfactants are proposed as clay swelling inhibitors in fracturing fluids to reduce the fractured face skin. For this purpose, several coreflooding and breakdown pressure experiments were conducted on the Scioto sandstone samples, and the rock mechanical properties of the flooded samples after drying were assessed. Coreflooding experiments proceeded in a way that the samples were flooded with the investigated fluid and then postflooded with deionized water (DW). Rock mechanical parameters, such as compressive strength, tensile strength, and linear elastic properties, were evaluated using unconfined compressive strength test, scratch test, indirect Brazilian disc test, and breakdown pressure test. The performance of novel synthesized surfactants was compared with commercially used clay stabilizing additives such as sodium chloride (NaCl) and potassium chloride (KCl). For comparison, base case experiments were performed with untreated samples and samples treated with DW. Scioto sandstone samples with high illite contents were used in this study. Results showed that the samples treated with conventional electrolyte solutions lost permeability up to 65% when postflooded with DW. In contrast, fracturing fluid containing surfactant solutions retained the original permeability even after being postflooded with DW. Conventional clay stabilizing additives led to the swelling of clays caused by high compression and tensile strength of the rock when tested at dry conditions. Consequently, the rock fractures at a higher breakdown pressure. However, novel dicationic surfactants do not cause any swelling, and therefore, the rock fractures at the original breakdown pressure.
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http://dx.doi.org/10.1021/acsomega.1c01388DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8223418PMC
June 2021

Hypertension and obesity in living kidney donors.

World J Transplant 2021 Jun;11(6):180-186

Department of Medicine, Division of Nephrology, Medical University of South Carolina, Charleston, SC 29425, United States.

Over the past few decades, the shortage in the kidney donor pool as compared to the increasing number of candidates on the kidney transplant waitlist led to loosening of kidney donors' acceptance criteria. Hypertension and obesity represent risk factors for chronic kidney disease, both in native kidneys and those in kidney transplant recipients. While great progress has been made in kidney transplantation from living donors to benefit the recipient survival and quality of life, progress has been slow to fully risk-characterize the donors. This review critically reassesses the current state of understanding regarding the risk of end-stage kidney disease in those donors with obesity, hypertension or both. Accurate risk assessment tools need to be developed urgently to fully understand the risk glomerular filtration rate compensation failure in the remaining kidney of the donors.
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http://dx.doi.org/10.5500/wjt.v11.i6.180DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8218343PMC
June 2021

Pharm.D.s and M.D.s in the Transplant World - Friends, Foes, Competitors or All are in Evolution?

Saudi J Kidney Dis Transpl 2021 Jan-Feb;32(1):1-8

Department of Medicine, Division of Nephrology, Medical University of South Carolina, Charleston, SC, USA.

Mutual trust, efforts, and commitment between patients and providers are essential for a successful, long-lasting renal transplant. From the renal transplant recipient's side, non-adherence to the medication has gained recognition as a predominant cause of late antibody-mediated rejection. Since the early 1970s, pharmacists have been involved in the care of transplant recipients and the incorporation of transplant pharmacists has improved the outcomes in solid organ transplantation. Such involvement of clinical pharmacists extends beyond improving graft outcomes: various studies demonstrated benefits in the care of diabetes, hypertension, and hyperlipidemia, with commensurate reduction of cardiovascular risk. From a unique perspective, this overview aimed to discuss the emerging role of Pharm. D.s and clinical pharmacists in general as it relates to team care, education of patients and healthcare providers and the sometimes conflicting relationship between physicians and pharmacists. Additional clinically relevant studies from culturally diverse settings are needed to explore the responsibilities of clinical team members to ensure optimized teamwork efforts without overlapping and duplication of efforts.
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http://dx.doi.org/10.4103/1319-2442.318510DOI Listing
June 2021

Inferences for Weibull Fréchet Distribution Using a Bayesian and Non-Bayesian Methods on Gastric Cancer Survival Times.

Comput Math Methods Med 2021 26;2021:9965856. Epub 2021 May 26.

Mathematics Department, Faculty of Science, Mansoura University, Mansoura 35516, Egypt.

In this article, based on progressively type-II censored schemes, the maximum likelihood, Bayes, and two parametric bootstrap methods are used for estimating the unknown parameters of the Weibull Fréchet distribution and some lifetime indices as reliability and hazard rate functions. Moreover, approximate confidence intervals and asymptotic variance-covariance matrix have been obtained. Markov chain Monte Carlo technique based on Gibbs sampler within Metropolis-Hasting algorithm is used to generate samples from the posterior density functions. Furthermore, Bayesian estimate is computed under both balanced square error loss and balanced linear exponential loss functions. Simulation results have been implemented to obtain the accuracy of the estimators. Finally, application on the survival times in years of a group of patients given chemotherapy and radiation treatment is presented for illustrating all the inferential procedures developed here.
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http://dx.doi.org/10.1155/2021/9965856DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8175177PMC
May 2021

Detection of relevant extracardiac findings on coronary computed tomography angiography vs. invasive coronary angiography.

Eur Radiol 2021 Jun 15. Epub 2021 Jun 15.

Department of Radiology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Germany.

Objectives: To compare the detection of relevant extracardiac findings (ECFs) on coronary computed tomography angiography (CTA) and invasive coronary angiography (ICA) and evaluate the potential clinical benefit of their detection.

Methods: This is the prespecified subanalysis of ECFs in patients presenting with a clinical indication for ICA based on atypical angina and suspected coronary artery disease (CAD) included in the prospective single-center randomized controlled Coronary Artery Disease Management (CAD-Man) study. ECFs requiring immediate therapy and/or further workup including additional imaging were defined as clinically relevant. We evaluated the scope of ECFs in 329 patients and analyzed the potential clinical benefit of their detection.

Results: ECFs were detected in 107 of 329 patients (32.5%; CTA: 101/167, 60.5%; ICA: 6/162, 3.7%; p < .001). Fifty-nine patients had clinically relevant ECFs (17.9%; CTA: 55/167, 32.9%; ICA: 4/162, 2.5%; p < .001). In the CTA group, ECFs potentially explained atypical chest pain in 13 of 101 patients with ECFs (12.9%). After initiation of therapy, chest pain improved in 4 (4.0%) and resolved in 7 patients (6.9%). Follow-up imaging was recommended in 33 (10.0%; CTA: 30/167, 18.0%; ICA: 3/162, 1.9%) and additional clinic consultation in 26 patients (7.9%; CTA: 25/167, 15.0%; ICA: 1/162, 0.6%). Malignancy was newly diagnosed in one patient (0.3%; CTA: 1/167, 0.6%; ICA: 0).

Conclusions: In this randomized study, CTA but not ICA detected clinically relevant ECFs that may point to possible other causes of chest pain in patients without CAD. Thus, CTA might preclude the need for ICA in those patients.

Trial Registration: NCT Unique ID: 00844220 KEY POINTS: • CTA detects ten times more clinically relevant ECFs than ICA. • Actionable clinically relevant ECFs affect patient management and therapy and may thus improve chest pain. • Detection of ECFs explaining chest pain on CTA might preclude the need for performing ICA.
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http://dx.doi.org/10.1007/s00330-021-07967-xDOI Listing
June 2021

Potency of plant extracts against Penicillium species isolated from different seeds and fruits in Saudi Arabia.

Saudi J Biol Sci 2021 Jun 4;28(6):3294-3302. Epub 2021 Mar 4.

Department of Biochemistry, College of Science, King Saud University, PO Box 22452, Riyadh 11451, Saudi Arabia.

Antifungal activity of extracts of cinnamon (Cinnamomum zeylanicum), Cloves (Syzygium aromaticum), ginger (Zingiber officinale) and turmeric (Curcuma longa) were evaluated against 17 . Seed disease and rotten fruit caused by these species cause considerable loss of quality for different agricultural products. Isolates of spp. were screened for production of patulin an important serious mycotoxin. About 70.59% of spp. produced this toxin in concentrations ranging from 4 to 31 ppb. The response of spp. to plant extracts differed according to the plant extract and concentration. Cinnamon extract showed the greatest effect on , and cloves extract produced the greatest effect on . Turmeric extract had less effect on . Cloves extract was the most effective in reducing the growth of . On the other hand, ginger extract with all concentrations used had less effect against most spp in the laboratory. Plant extracts are promising as natural sources of environmentally friendly compounds in laboratory studies.
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http://dx.doi.org/10.1016/j.sjbs.2021.02.074DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8176084PMC
June 2021

An Artificial Intelligence-Based Model for Performance Prediction of Acid Fracturing in Naturally Fractured Reservoirs.

ACS Omega 2021 Jun 18;6(21):13654-13670. Epub 2021 May 18.

College of Petroleum Engineering & Geosciences, King Fahd University of Petroleum & Minerals, Dhahran 31261, Saudi Arabia.

Acid fracturing is one of the most effective techniques for improving the productivity of naturally fractured carbonate reservoirs. Natural fractures (NFs) significantly affect the design and performance of acid fracturing treatments. However, few models have considered the impact of NFs on acid fracturing treatments. This study presents a simple and computationally efficient model for evaluating acid fracturing efficiency in naturally fractured reservoirs using artificial intelligence-based techniques. In this work, the productivity enhancement due to acid fracturing is determined by considering the complex interactions between natural and hydraulic fractures. Several artificial intelligence (AI) techniques were examined to develop a reliable predictive model. An artificial neural network (ANN), a fuzzy logic (FL) system, and a support vector machine (SVM) were used. The developed model predicts the productivity improvement based on reservoir permeability and geomechanical properties (e.g., Young's modulus and closure stress), natural fracture properties, and design conditions (i.e., acid injection rate, acid concentration, treatment volume, and acid types). Also, several evaluation indices were used to evaluate the model reliability including the correlation coefficient, average absolute percentage error, and average absolute deviation. The AI model was trained and tested using more than 3100 scenarios for different reservoir and treatment conditions. The developed ANN model can predict the productivity improvement with a 3.13% average absolute error and a 0.98 correlation coefficient, for the testing (unseen) data sets. Moreover, an empirical equation was extracted from the optimized ANN model to provide a direct estimation for productivity improvement based on the reservoir and treatment design parameters. The extracted equation was evaluated using validation data where a 4.54% average absolute error and a 0.99 correlation coefficient were achieved. The obtained results and degree of accuracy show the high reliability of the proposed model. Compared to the conventional simulators, the developed model reduces the time required for predicting the productivity improvement by more than 60-fold; therefore, it can be used on the fly to select the best design scenarios for naturally fractured formations.
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http://dx.doi.org/10.1021/acsomega.1c00809DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8173587PMC
June 2021

Production of biodiesel from oleaginous fungal lipid using highly catalytic bimetallic gold-silver core-shell nanoparticle.

J Appl Microbiol 2021 Jun 6. Epub 2021 Jun 6.

Biology Department, College of Science, Princess Nourah Bint Abdulrahman University, Riyadh, Saudi Arabia.

Aims: This study aims to synthesize, characterize and apply gold-silver core-shell nanoparticles ([email protected] NPs), a nanocatalyst, to maximize biodiesel production from fungal isolate Fusarium solani (FS12) via a transesterification one-step reaction.

Methods And Results: The [email protected] NPs structure was examined by UV-vis spectrophotometer, transmission electron microscopy, X-ray diffraction and Fourier transform infrared (FTIR). All devices were used to characterize [email protected] NPs and confirmed successful synthesis of nanoparticles. Fungal lipid was quantitatively determined by sulfo-phospho-vanillin colorimetric method. Among 15 F. solani isolates obtained from rhizospheric soils of the date palm, F. solani (AF12) was chosen as the highly significant producer that accumulates above 20% lipid. The maximum biodiesel yield was 91.28 ± 0.19%, obtained under the optimum reaction conditions of 3% [email protected] NPs as nanocatalyst concentration, and 1:20 oil to methanol molar ratio at 70℃ for 30 min. HPLC method was applied for monitoring in situ transesterification reaction. FTIR spectroscopy was used in qualitative analysis of biodiesel by verifying the presence of unique characteristic peaks of diagnostic significance. The quality of the biodiesel produced was confirmed by the high purity of fatty acid methyl esters analysis content up to >99%.

Conclusions: These findings propose the applicability of F. solani (FS12) as a promising isolate to accumulate lipids and biodiesel production as a feedstock.

Significance And Impact Of The Study: The link between nanotechnology and fungi. [email protected] NPs were synthesized at room temperature, which displayed high catalytic activity for in situ transesterification reaction. Catalytic activity appeared at low temperature, mole ratio and short reaction time. Oleaginous fungi are described as easily grown, have short life cycle, are cost-effective, and they utilized various sources of carbon up to waste and a simplified process to develop scale-up production as well, economic value, opposite the usage of vegetable oils which need for large agricultural areas.
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http://dx.doi.org/10.1111/jam.15176DOI Listing
June 2021

Massive gastrointestinal bleeding in a patient with COVID-19.

Arab J Gastroenterol 2021 Jun 14;22(2):177-179. Epub 2021 May 14.

Infectious Disease Consultants and Academic Researchers of Egypt (IDCARE), Egypt.

Despite the emerging data about the thrombophilic effect of the novel coronavirus [1] , the relation between coagulation disorders and the COVID-19 pandemic is still not well understood. Various studies pointed to the significant role of the COVID-19 induced cytokine storm in development of the hypercoagulable state which leads to serious thromboembolic complications [2,3] . Some studies report the development of severe immune thrombocytopenia induced by the novel coronavirus [4] . Other studies found a correlation between COVID-19 disease and the development of disseminated intravascular coagulation (DIC) [5]. Patients with severe COVID-19 disease have an increased risk for development of gastrointestinal bleeding (GI) which may be related to stress [6] , critical illness or mechanical ventilation [7] . Further studies showed the ability of the novel coronavirus to infect the epithelial cells of the GI tract [8] . Moreover, some data pointed to the ability of the virus even to infect the endothelium of blood vessels [9]. The relation between the COVID-19 pandemic and GI bleeding deserves more studies [10]. We present a case of GI bleeding in a patient with severe COVID-19 disease. We assume that COVID-19 disease can be a predominant factor for the development of DIC and GI bleeding.
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http://dx.doi.org/10.1016/j.ajg.2021.05.008DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8118668PMC
June 2021

A Surface Charge Approach to Investigating the Influence of Oil Contacting Clay Minerals on Wettability Alteration.

ACS Omega 2021 May 7;6(19):12841-12852. Epub 2021 May 7.

Center for Integrative Petroleum Research (CIPR), College of Petroleum Engineering and Geosciences, King Fahd University of Petroleum and Minerals, 31261 Dhahran, Kingdom of Saudi Arabia.

Reservoir rock wettability has been linked to the adsorption of crude fractions on the rock, with much attention often paid to the bulk mineralogy rather than contacting minerals. Crude oil is contacted by different minerals that contribute to rock wettability. The clay mineral effect on wettability alterations is examined using the mineral surface charge. Also, the pH change effect due to well operations was investigated. Clay mineral surface charge was examined using zeta potential computed from the particle electrophoretic mobility. Clay minerals considered in this study include kaolinite, montmorillonite, illite, and chlorite. Results reveal that the clay mineral charge development is controlled by adsorption of ionic species and double layer collapse. Also, clay mineral surface charge considered in this study shows that their surfaces become more conducive for the adsorption of hydrocarbon components due to the presence of salts. The salt effect is greater in the following order: NaHCO < NaSO < NaCl < MgCl < CaCl. Furthermore, different well operations induce pH environments that change the clay mineral surface charge. This change results in adsorption prone surfaces and with reservoir rock made up of different minerals, and the effect of contacting minerals is critical as shown in our findings. This is due to the contacting mineral control wettability rather than the bulk mineralogy.
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http://dx.doi.org/10.1021/acsomega.1c01221DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8154241PMC
May 2021

The safety aspects of accepting living kidney donors with pelvi-ureteric junction dysfunction.

Int Urol Nephrol 2021 May 24. Epub 2021 May 24.

Nephrology Division, Department of Medicine, University of Tennessee Health Science Center, Memphis, TN, 38163, USA.

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http://dx.doi.org/10.1007/s11255-021-02893-9DOI Listing
May 2021

Evaluation of super-obesity and super-super-obesity as risk factors for difficult intubation in patients undergoing bariatric surgery.

Surg Obes Relat Dis 2021 Jul 6;17(7):1279-1285. Epub 2021 Apr 6.

Department of Anesthesia and Critical Care Medicine, Cairo University, Cairo, Egypt.

Background: Super-obesity is a serious disorder which requires bariatric surgery. The association of super-obesity and difficult intubation was not adequately established.

Objectives: To determine if super-obesity and super-super-obesity are associated with difficult intubation or not.

Setting: University Hospital.

Methods: A cohort of obese patients scheduled for bariatric surgery was prospectively recruited. Super-obesity and super-super-obesity were defined as body mass index ≥50 kg/m and 60 kg/m, respectively. Intubation difficulty was assessed by 2 methods: (1) intubation difficulty scale; (2) number of intubation attempts. Risk factors for difficult intubation were recorded. Univariate and multivariate analysis for risk factors for difficult intubation and difficult mask ventilation were performed.

Results: A total of 658 patients were enrolled in the study including 205 (31%) super-obese and 52 (8%) super-super-obese patients. Ninety-nine (15%) patients required more than 1 intubation attempt, while 215 (33%) patients had intubation difficulty scale ≥5. Ninety-four (14.4%) patients had mask ventilation of moderate difficulty, while only 2 (.3%) patients needed 2-person ventilation. The independent risk factors for difficult intubation using the two stated definitions were STOP-Bang and Mallampati score values. The independent risk factors for mask ventilation of moderate difficulty were STOP-Bang score, Mallampati score, and limited neck extension.

Conclusion: Within obese patients, neither super-obesity nor super-super-obesity was associated with difficult intubation or difficult mask ventilation. High STOP-Bang and Mallampati score are the independent factors for difficult intubation.
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http://dx.doi.org/10.1016/j.soard.2021.03.028DOI Listing
July 2021

Hydrocarbon biodegradation and transcriptome responses of cellulase, peroxidase, and laccase encoding genes inhabiting rhizospheric fungal isolates.

Saudi J Biol Sci 2021 Apr 21;28(4):2083-2090. Epub 2021 Jan 21.

Molecular Markers Laboratory, Plant Pathology Research Institute, Agricultural Research Center, Giza 12619, Egypt.

By using the indigenous micro-organisms of the polluted environment to be treated, bioremediation can be a successful strategy. PCR and RT-PCR molecular techniques were applied to examine the evolution of fungal isolates through putative genes f ligninolytic enzymes like lignin peroxidase (LiP), laccase (LaC), manganese peroxidase (MnP), and cellulase (Cx) as a response to polluting of the environment by hydrocarbons. In this study, isolation of rhizospheric fungal isolates, molecular identification, crude oil tolerance, and enzyme excretions were demonstrated. From the date palm rhizosphere, 3 fungal isolates were isolated and characterized morphologically and molecularly by ITS ribosomal RNA (rRNA) sequencing. The isolates were identified as AF15, TH07, and FS12 through using the BLAST tool in NCBI. All fungal isolates showed high tolerance to crude oil and survived with various responses at the highest concentration (20%). AF15 and TH07 demonstrated promising oil-degrading tolerance ability based on the dose inhibition response percentage (DIRP) of the fungal isolates. had a powerful capacity to production Cx, LaC, LiP and MnP with a range from 83.7 to 96.3 mL. Molecularly, nine genes of the ligninolytic enzymes, (, , ) , (1, 2, 4 and 6) and were tested for presence and expression (by PCR and RT-PCR, respectively). PCR showed that all isolates contained all the nine genes examined, regardless of capacity to enzymes production profiles, so the presence responses of nine genes did not correlate with enzymes-production ability. Gene expression analysis shows a more diverse pattern for tested isolates for example, AF15 had over-expression of and genes, FS12 have a weak signal with gene while, TH07 showed moderate expression of and genes. The power of the transcription of the gene leads to increased enzyme secretion by fungal isolates. Fungi are important microorganisms in the clean-up of petroleum pollution. They have bioremediation highly potency that is related to their diverse production of these catalytic enzymes.
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http://dx.doi.org/10.1016/j.sjbs.2021.01.009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8071968PMC
April 2021

Leukemic Stem Cell (CD34/CD38/TIM3) Frequency in Patients with Acute Myeloid Leukemia: Clinical Implications.

Clin Lymphoma Myeloma Leuk 2021 Mar 27. Epub 2021 Mar 27.

Biochemistry Division, Chemistry Department, Faculty of Science, Mansoura University, Mansoura, Egypt.

This study aimed to address the prognostic relevance of CD34/CD38/TIM3 leukemic stem cell (LSC) frequency in patients with acute myeloid leukemia (AML) and its impact on patient outcome. We analyzed the expression of LSC markers (CD34/CD38/TIM3) using flow cytometry in bone marrow samples of 53 AML cases before and after induction chemotherapy. The LSC frequency at diagnosis was significantly higher compared with that postinduction (P < .001). Patients were categorized into high LSC expressers (≥ median) and low expressers (< median). Patients with AML with high number of LSCs at diagnosis had significantly lower induction of remission response (P = .0104), shorter disease-free survival, and shorter overall survival (P < .001 for both) compared with those with lower LSC count. Cox regression analysis revealed that LSC frequency at diagnosis is an independent prognostic factor in AML. Assessment of LSCs (CD34/CD38/TIM3) at diagnosis is recommended for refining of AML risk stratification.
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http://dx.doi.org/10.1016/j.clml.2021.03.009DOI Listing
March 2021

Wi-Fi Assisted Contextual Multi-Armed Bandit for Neighbor Discovery and Selection in Millimeter Wave Device to Device Communications.

Sensors (Basel) 2021 Apr 17;21(8). Epub 2021 Apr 17.

Electrical Engineering Department, College of Engineering, Prince Sattam Bin Abdulaziz University, Wadi Addwasir 11991, Saudi Arabia.

The unique features of millimeter waves (mmWaves) motivate its leveraging to future, beyond-fifth-generation/sixth-generation (B5G/6G)-based device-to-device (D2D) communications. However, the neighborhood discovery and selection (NDS) problem still needs intelligent solutions due to the trade-off of investigating adjacent devices for the optimum device choice against the crucial beamform training (BT) overhead. In this paper, by making use of multiband (μW/mmWave) standard devices, the mmWave NDS problem is addressed using machine-learning-based contextual multi-armed bandit (CMAB) algorithms. This is done by leveraging the context information of Wi-Fi signal characteristics, i.e., received signal strength (RSS), mean, and variance, to further improve the NDS method. In this setup, the transmitting device acts as the player, the arms are the candidate mmWave D2D links between that device and its neighbors, while the reward is the average throughput. We examine the NDS's primary trade-off and the impacts of the contextual information on the total performance. Furthermore, modified energy-aware linear upper confidence bound (EA-LinUCB) and contextual Thomson sampling (EA-CTS) algorithms are proposed to handle the problem through reflecting the nearby devices' withstanding battery levels, which simulate real scenarios. Simulation results ensure the superior efficiency of the proposed algorithms over the single band (mmWave) energy-aware noncontextual MAB algorithms (EA-UCB and EA-TS) and traditional schemes regarding energy efficiency and average throughput with a reasonable convergence rate.
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http://dx.doi.org/10.3390/s21082835DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8073343PMC
April 2021

Molecular mechanisms underlying antitumor activity of camel whey protein against multiple myeloma cells.

Saudi J Biol Sci 2021 Apr 28;28(4):2374-2380. Epub 2021 Jan 28.

Department of Biochemistry, College of Science, King Saud University, PO Box 22452, Riyadh 11451, Saudi Arabia.

Treating drug-resistant cancer cells is a clinical challenge and it is also vital to screen for new cancer drugs. Multiple myeloma (MM) is a plasma cell clonal cancer that, despite many experimental therapeutics, remains incurable. In this study, two MM cell line lines U266 and RPMI 8226 were used to determine the impact of camel whey protein (CWP). The CWP IC was calculated by MTT examination, while the flow cytometry analysis was used to investigate the chemotaxis responses of MM cells in relation to CXCL12 and the pro-apoptotic effect of CHP. MM cells were treated with CWP and Western blot analysis was used to determine the underlying molecular mechanisms. Dose and time based on the impact of CWP on the cell viability of MM cells with IC of 50 μg/ml, without affecting the viability of normal healthy PBMCs. CWP reduced chemotaxis of MM cells significantly from the CXC chemokine ligand 12 (CXCL12). Using Western blot analysis, we found that CWP decreased the activation of AKT, mTOR, PLCβ3, NFαB and ERK, which was mechanistically mediated by CXCL12/CXCR4. In both U266 and RPMI 8226, CWP induced apoptosis by upregulating cytochrome expression. In addition, CWP mediated the growth arrest of MM cells by robustly decreasing the expression of the anti-apoptotic Bcl-2 family members Bcl-2, Bcl-XL and Mcl-1. Conversely, the expression of pro-apoptotic Bcl-2 family members Bak, Bax and Bim was increased after treatment with CWP. Our data indicates CWP's therapeutic potential for MM cells.
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http://dx.doi.org/10.1016/j.sjbs.2021.01.034DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8071924PMC
April 2021

Outcomes of Interleukin-2 Receptor Antagonist Induction Therapy in Standard-Risk Renal Transplant Recipients Maintained on Tacrolimus: A Systematic Review and Meta-Analysis.

Am J Nephrol 2021 22;52(4):279-291. Epub 2021 Apr 22.

Institute of Medical Sciences, Faculty of Medicine, University of Liverpool, Liverpool, United Kingdom.

Introduction: The additive benefit of interleukin-2 receptor antagonist (IL2-RA) induction in standard-risk kidney transplant recipients, while maintained on tacrolimus-based immunosuppressive therapy, is uncertain.

Methods: We divided the studies included in this meta-analysis into 2 groups: group A (included studies that used same dose of tacrolimus in both arms of each study) and group B (included studies that compared patients who received induction therapy and low-dose tacrolimus vs. those who received no-induction therapy and high dose of tacrolimus).

Results: In group A, 11 studies were included (n = 2,886). IL2-RA induction therapy was not associated with significant differences in comparison to no-induction therapy in terms of acute rejection rates at 6 months post-transplant (risk ratio = 1.12 and 95% confidence interval [CI] range: 0.94-1.35) or graft survival at 1 year post-transplant (risk ratio = 0.78 and 95% CI range: 0.45-1.36). In group B, 2 studies were included (n = 669). There was no difference between both arms in terms of acute rejection rates (risk ratio = 0.62, with 95% CI range: 0.33-1.14) or graft survival (risk ratio = 1 and 95% CI range: 0.57-1.74).

Conclusion: IL2-RA induction therapy does not improve outcomes in patients maintained on tacrolimus-based immunotherapy in standard-risk population.
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http://dx.doi.org/10.1159/000514454DOI Listing
April 2021

Evaluation of the Ameliorative Effect of Zinc Nanoparticles against Silver Nanoparticle-Induced Toxicity in Liver and Kidney of Rats.

Biol Trace Elem Res 2021 Apr 14. Epub 2021 Apr 14.

Department of Toxicology and Forensic Medicine, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt.

Silver nanoparticles (Ag-NPs) have various pharmaceutical and biomedical applications owing to their unique physicochemical properties. Zinc (Zn) is an essential trace element, a strong antioxidant, and has a primary role in gene expression, enzymatic reactions, and protein synthesis. The present study aims to explore the toxic effects of Ag-NPs (50 nm) on the liver and kidney of rats and also to evaluate the potential protective effect of Zn-NPs (100 nm) against these adverse effects. Forty adult Sprague-Dawley rats were randomly divided into four equal groups: control group, Ag-NPs group, Zn-NPs group, and Ag-NPs + Zn-NPs group. Ag-NPs (50 mg/kg) and/or Zn-NPs (30 mg/kg) were administered daily by gavage for 90 days. The results showed that exposure to Ag-NPs increased serum ALT, AST, urea, and creatinine. Ag-NPs also induced oxidative stress and lipid peroxidation and increased inflammatory cytokines in hepatic and renal tissues. Moreover, histopathological and immunohistochemical examinations revealed various histological alterations and positive caspase-3 expressions in the liver and kidney following exposure to Ag-NPs. On the other hand, most of these toxic effects were ameliorated by co-administration of Zn-NPs. It was concluded that Ag-NPs have hepatotoxic and nephrotoxic effects in rats via different mechanisms including oxidative stress, inflammation, and apoptosis and that Zn-NPs can be used to alleviate these harmful effects by their antioxidative, anti-inflammatory, and antiapoptotic properties.
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http://dx.doi.org/10.1007/s12011-021-02713-2DOI Listing
April 2021

High-Speed Atomic Force Microscopy Reveals Spatiotemporal Dynamics of Histone Protein H2A Involution by DNA Inchworming.

J Phys Chem Lett 2021 Apr 14;12(15):3837-3846. Epub 2021 Apr 14.

Division of Nano Life Science in the Graduate School of Frontier Science Initiative, WISE Program for Nano-Precision Medicine, Science and Technology, Kanazawa University, Kanazawa, Ishikawa 920-1192, Japan.

DNA-histone interaction is always perturbed by epigenetic regulators to regulate gene expression. Direct visualization of this interaction is yet to be achieved. By using high-speed atomic force microscopy (HS-AFM), we have observed the dynamic DNA-histone H2A interaction. HS-AFM movies demonstrate the globular core and disordered tail of H2A. DNA-H2A formed the classic "beads-on-string" conformation on poly-l-lysine (PLL) and lipid substrates. Notably, a short-linearized double-stranded DNA (dsDNA), resembling an inchworm, wrapped around a single H2A protein only observed on the lipid substrate. Such a phenomenon does not occur for plasmid DNA or linearized long dsDNA on the same substrate. Strong adsorption of PLL substrate resulted in poor dynamic DNA-H2A interaction. Nonetheless, short-linearized dsDNA-H2A formed stable wrapping with a "diamond ring" topology on the PLL substrate. Reversible liquid-liquid phase separation (LLPS) of the DNA-H2A aggregate was visualized by manipulating salt concentrations. Collectively, our study suggest that HS-AFM is feasible for investigating epigenetically modified DNA-histone interactions.
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http://dx.doi.org/10.1021/acs.jpclett.1c00697DOI Listing
April 2021

Studying the Influence of Copper on the Growth Behavior, Antioxidative Status, and Histology of the Intestine and Liver of Striped Catfish (Pangasianodon hypophthalmus).

Biol Trace Elem Res 2021 Apr 14. Epub 2021 Apr 14.

Department of Animal Production, Faculty of Agriculture, Kafrelsheikh University, Kafrelsheikh, 33516, Egypt.

Microelements are well recognized as an essential approach in the field of aquaculture nutrition. Thus, this study aimed to evaluate copper (Cu) inclusion (0, 0.5, 1, and 2 mg/kg) on Striped catfish performances. Fish fed the Cu-incorporated diets for 60 days, then their growth behavior, antioxidative capacity, and intestinal and liver histological features were evaluated. The results showed a marked enhancement in Striped catfish's growth behavior fed 1-2 mg/kg of Cu, as shown by the final weight, weight gain, and specific growth rate. The feed and protein efficiency ratios were significantly affected by Cu in a dose-dependent manner. The highest level of Cu was accumulated in the whole body, muscle, liver, and gills of fish fed 2 mg/kg of Cu. The carcass composition of Striped catfish showed higher protein content in groups received 0.5, 1, and 2 mg/kg Cu in a linear and quadratic manner (p=0.001). The ash content was quadratically increased in Striped catfish fed 2 mg/kg Cu (p=0.001). However, no marked effects were observed on the moisture and lipid contents and the somatic indices (p>0.05). The incorporation of Cu showed meaningfully increased superoxide dismutase, catalase, and glutathione peroxidase but decreased malondialdehyde level in Striped catfish. The villous height exhibited visible growth and branching with increased doses of Cu without a significant increase in the goblet cells. No abnormal features were observed in the liver and hepatocytes of fish treated with Cu. It can be concluded that Cu is required at 1-2 mg/kg for better performances of Striped catfish.
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http://dx.doi.org/10.1007/s12011-021-02717-yDOI Listing
April 2021

Zinc Nanoparticles Ameliorate the Reproductive Toxicity Induced by Silver Nanoparticles in Male Rats.

Int J Nanomedicine 2021 31;16:2555-2568. Epub 2021 Mar 31.

Department of Toxicology and Forensic Medicine, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt.

Introduction: Silver nanoparticles (Ag-NPs) are among the most commonly used nanoparticles in different fields. Zinc nanoparticles (Zn-NPs) are known for their antioxidant effect. This study was designed to investigate the adverse effects of Ag-NPs (50 nm) on the male reproductive system and also the ameliorative effect of Zn-NPs (100 nm) against these harmful effects.

Methods: Forty adult male rats were used in this study; they were randomly divided into four equal groups: control group, Ag-NPs group, Zn-NPs group, Ag-NPs + Zn-NPs group. Ag-NPs (50 mg/kg) and/or Zn-NPs (30 mg/kg) were administered orally for 90 days.

Results: The results revealed that exposure to Ag-NPs adversely affected sperm motility, morphology, viability, and concentration. Ag-NPs also induced oxidative stress and lipid peroxidation in testicular tissue. The exposure to Ag-NPs decreased serum FSH, LH, and testosterone hormones. Additionally, comet assay revealed DNA degeneration in the testicular tissue of rats exposed to Ag-NPs. Histopathological examination showed various histological alterations in the testes of rats intoxicated with Ag-NPs. Furthermore, co-administration of Zn-NPs ameliorated most of the toxic effects of Ag-NPs via their antioxidative capacity.
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http://dx.doi.org/10.2147/IJN.S307189DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8020588PMC
April 2021

Non-local Muscle Fatigue Effects on Muscle Strength, Power, and Endurance in Healthy Individuals: A Systematic Review with Meta-analysis.

Sports Med 2021 Apr 5. Epub 2021 Apr 5.

School of Sport, Health and Social Science, Solent University, Southampton, UK.

Background: The fatigue of a muscle or muscle group can produce global responses to a variety of systems (i.e., cardiovascular, endocrine, and others). There are also reported strength and endurance impairments of non-exercised muscles following the fatigue of another muscle; however, the literature is inconsistent.

Objective: To examine whether non-local muscle fatigue (NLMF) occurs following the performance of a fatiguing bout of exercise of a different muscle(s).

Design: Systematic review and meta-analysis.

Search And Inclusion: A systematic literature search using a Boolean search strategy was conducted with PubMed, SPORTDiscus, Web of Science, and Google Scholar in April 2020, and was supplemented with additional 'snowballing' searches up to September 2020. To be included in our analysis, studies had to include at least one intentional performance measure (i.e., strength, endurance, or power), which if reduced could be considered evidence of muscle fatigue, and also had to include the implementation of a fatiguing protocol to a location (i.e., limb or limbs) that differed to those for which performance was measured. We excluded studies that measured only mechanistic variables such as electromyographic activity, or spinal/supraspinal excitability. After search and screening, 52 studies were eligible for inclusion including 57 groups of participants (median sample = 11) and a total of 303 participants.

Results: The main multilevel meta-analysis model including all effects sizes (278 across 50 clusters [median = 4, range = 1 to 18 effects per cluster) revealed a trivial point estimate with high precision for the interval estimate [- 0.02 (95% CIs = - 0.14 to 0.09)], yet with substantial heterogeneity (Q = 642.3, p < 0.01), I = 67.4%). Subgroup and meta-regression analyses showed that NLMF effects were not moderated by study design (between vs. within-participant), homologous vs. heterologous effects, upper or lower body effects, participant training status, sex, age, the time of post-fatigue protocol measurement, or the severity of the fatigue protocol. However, there did appear to be an effect of type of outcome measure where both strength [0.11 (95% CIs = 0.01-0.21)] and power outcomes had trivial effects [- 0.01 (95% CIs = - 0.24 to 0.22)], whereas endurance outcomes showed moderate albeit imprecise effects [- 0.54 (95% CIs = - 0.95 to - 0.14)].

Conclusions: Overall, the findings do not support the existence of a general NLMF effect; however, when examining specific types of performance outcomes, there may be an effect specifically upon endurance-based outcomes (i.e., time to task failure). However, there are relatively fewer studies that have examined endurance effects or mechanisms explaining this possible effect, in addition to fewer studies including women or younger and older participants, and considering causal effects of prior training history through the use of longitudinal intervention study designs. Thus, it seems pertinent that future research on NLMF effects should be redirected towards these still relatively unexplored areas.
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http://dx.doi.org/10.1007/s40279-021-01456-3DOI Listing
April 2021

Promoting Visible Light Generation of Hydrogen Using a Sol-Gel-Prepared [email protected] p-n Heterojunction Photocatalyst.

ACS Omega 2021 Mar 17;6(12):8717-8725. Epub 2021 Mar 17.

Department of Chemistry, College of Science, Taif University, P.O. Box 11099, Taif 21944, Saudi Arabia.

The production of hydrogen using a new type of heterogeneous photocatalyst under visible light is considered a remarkable essential pathway for sustainable, pure energy not only on the laboratory scale but also on a bigger scale. Hence, a new nanocomposite of mesoporous MnCoO, g-CN, and [email protected] was produced utilizing a sol-gel method with variable MnCoO contents. The crystal structure of MnCoO was effectively confirmed by the X-ray diffraction pattern and integrated onto the g-CN structure. The MnCoO nanoparticles were displayed as spherical particles by TEM images and dispersed in a uniform way inside the g-CN nanosheet. The synthesized nanocomposites in the form of [email protected] were examined as a new effective photocatalyst against glycerol as a source for H production with visible light. The MnCoO contents indicated a corroborative impact for the photocatalytic action related to the H production process. A maximum H production molecular value was observed (21,870 μmol·g·h) for a 1.5 wt % [email protected] nanocomposite as a considerable increase in its photocatalytic activity. The yields of H are ∼55 and 23 times higher than those of g-CN and MnCoO, respectively. Up to five times cycles of visible lighting were the maximum number of repeated cycles by which the 1.5 wt % [email protected] product showed higher stability and durability.
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http://dx.doi.org/10.1021/acsomega.1c00697DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8015085PMC
March 2021

Bioactive Potential of Several Actinobacteria Isolated from Microbiologically Barely Explored Desert Habitat, Saudi Arabia.

Biology (Basel) 2021 Mar 19;10(3). Epub 2021 Mar 19.

Integrated Molecular Plant Physiology Research, Department of Biology, University of Antwerp, 2020 Antwerp, Belgium.

Biomolecules from natural sources, including microbes, have been the basis of treatment of human diseases since the ancient times. Therefore, this study aimed to investigate the potential bioactivity of several actinobacteria isolates form Al-Jouf Desert, Saudi Arabia. Twenty-one actinobacterial isolates were tested for their antioxidant (flavonoids, phenolics, tocopherols and carotenoids) content, and biological activities, namely FRAP, DPPH, ABTS, SOS and XO inhibition, anti-hemolytic and anti-lipid peroxidation as well as their antibacterial and antiprotozoal activities. Accordingly, five isolates (i.e., Act 2, 12, 15, 19 and 21) were selected and their 90% ethanolic extracts were used. The phylogenetic analysis of the 16S rRNA sequences indicated that the most active isolates belong to genus . The genus has been documented as a prolific producer of biologically active secondary metabolites against different cancer types. Thus, the anti-blood cancer activity and the possible molecular mechanisms by which several species extracts inhibited the growth of different leukemia cells, i.e., HL-60, K562 and THP-1, were investigated. In general, the five active isolates showed cytotoxic activity against the tested cell lines in a dose dependent manner. Among the potent isolates, isolate Act 12 significantly decreased the cell viability and showed maximum cytotoxic activities against both HL-60 and K562 cells, while isolate Act 15 exhibited maximum cytotoxic activity against THP-1 cells. Moreover, Act 2 and Act 12 reduced cyclooxygenase (COX-2) and lipoxygenase (LOX) activity, which is involved in the proliferation and differentiation of cancer cells and may represent a possible molecular mechanism underlying leukemia growth inhibition. The bioactive antioxidant extracts of the selected species inhibited leukemia cell growth by reducing the COX-2 and LOX activity. Overall, our study not only introduced a promising natural alternative source for anticancer agents, but it also sheds light on the mechanism underlying the anticancer activity of isolated actinomycetes.
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http://dx.doi.org/10.3390/biology10030235DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8003550PMC
March 2021
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