معهد البحوث والاستشارات الطبية||Institute for Research and Medical Consultations

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Genomic Landscape of Multidrug Resistance and Virulence in Enterococcus faecalis IRMC827A from a Long-Term Patient
(2023) Rahaf Khalid Al-Quwaie; AlJindan, Reem; Razan Aldahhan; Alquwaie, Rahaf; J. Francis Borgio; Reem AlJindan; AlEraky, Doaa M.; Noor Barak Almandil; Sayed AbdulAzeez; Doaa Mostafa AlEraky
We report on a highly virulent, multidrug-resistant strain of Enterococcus faecalis IRMC827A that was found colonizing a long-term male patient at a tertiary hospital in Khobar, Saudi Arabia. The E. faecalis IRMC827A strain carries several antimicrobial drug resistance genes and harbours mobile genetic elements such as Tn6009, which is an integrative conjugative element that can transfer resistance genes between bacteria and ISS1N via an insertion sequence. Whole-genome-sequencing-based antimicrobial susceptibility testing on strains from faecal samples revealed that the isolate E. faecalis IRMC827A is highly resistant to a variety of antibiotics, including tetracycline, doxycycline, minocycline, dalfopristin, virginiamycin, pristinamycin, chloramphenicol, streptomycin, clindamycin, lincomycin, trimethoprim, nalidixic acid and ciprofloxacin. The isolate IRMC827A carries several virulence factors that are significantly associated with adherence, biofilm formation, sortase-assembled pili, manganese uptake, antiphagocytosis, and spreading factor of multidrug resistance. The isolate also encompasses two mutations (G2576T and G2505A) in the 23S rRNA gene associated with linezolid resistance and three more mutations (gyrA p.S83Y, gyrA p.D759N and parC p.S80I) of the antimicrobial resistance phenotype. The findings through next-generation sequencing on the resistome, mobilome and virulome of the isolate in the study highlight the significance of monitoring multidrug-resistant E. faecalis colonization and infection in hospitalized patients. As multidrug-resistant E. faecalis is a serious pathogen, it is particularly difficult to treat and can cause fatal infections. It is important to have quick and accurate diagnostic tests for multidrug-resistant E. faecalis, to track the spread of multidrug-resistant E. faecalis in healthcare settings, and to improve targeted interventions to stop its spread. Further research is necessary to develop novel antibiotics and treatment strategies for multidrug-resistant E. faecalis infections.
Pulsed laser ablation-mediated facile fabrication of MoO3/TiO2/rGO nanocomposite as a photocatalyst for dye degradation
(2024) Umar Alhajri; Elsayed, Khaled A.; Manda, Abdullah A.; Haladu, Shamsuddeen A.; Shamsuddeen A. Haladu; Tarek Said Kayed; Kayed, T. S.; Çevik, Emre; Alhajri, Umar; Ercan, İsmail; Drmosh, Q. A.; Elhassan, A.
In this work, for the first time, the MoO3/TiO2/rGO nanocomposites with different weight ratios of rGO (0%, 5%, 10%, and 20%) were fabricated using pulsed laser ablation technique. The as-fabricated nanocomposites were employed for photodegradation of Methylene Blue (MB) under UV light irradiation. The morphological, structural, and chemical properties of the fabricated photocatalysts were characterized using XRD, TEM, SEM, UV-DRS, XPS, FTIR, TGA, DSC, and PL. Comparative experimental studies displayed that MoO3/TiO2/rGO nanocomposites fabricated with 5% rGO showed the highest photocatalytic degradation (95%) of MB under UV irradiation. This superior photocatalytic performance could be ascribed to the narrow bandgap of the fabricated nanocomposites as well as the synergistic effect of the three components.
Effect of CeO2/spherical silica and halloysite nanotubes engineered for targeted drug delivery system to treat breast cancer cells
(2023) Layan Almulla; Ravinayagam, Vijaya; Alghamdi, Norah; Alghamdi, Wejdan; Sarah Almofty; Almulla, Layan; Vijaya Ravinayagam; Almofleh, Ali Awad; Tanimu, Gazali; Dafalla, H.; Jermy, B. Rabindran
Cerium oxide nanoparticles (CeO2 NPs) and flavonoid curcumin that has been widely studied for treating diseases involving high reactive oxygen species (ROS). In nanotherapeutics, the particle size, shape, metal oxide dispersity and surface properties of nanocarriers are vital for drug delivery and therapeutic efficiency. Here, cisplatin release behavior on cerium impregnated two different shaped nanocarriers, CeO2/monodispersed spherical silica (Sil) and CeO2/halloysite (Hal) nanotube was studied for potential anti-cancer therapies. For comparison, CeO2 impregnated mesoporous silica MCM-41, SBA-16, Hydroxyapatite and clay were prepared. Subsequently, the nanocomposites were coated with curcumin (25% wt/wt), and cisplatin (Cp) functionalization (5% wt/wt). 5wt%CeO2/Hal/Cp and 5wt%CeO2/Sil/Cp samples were pegylated using lyophilization technique. Physico-chemical analyses revealed the nanosized distribution of CeO2 and functionalization of cisplatin and curcumin. Cp release was studied using automated Franz cell and dialysis membrane techniques. The different structured nanocarriers delivering mechanism was studied by determining the drug kinetic release using four different kinetic models (first order, second order, Higuchi and Korsmeyer-Peppas). In vitro cytotoxicity assay of nano formulations along with free cisplatin and curcumin (Cur) were tested against the breast cancer cell line (MCF-7) for multiple timepoints by MTT assay. The results reveled the efficacy of 5wt%CeO2/Sil/Cp/Cur nanoparticles in delivering cisplatin. On the other hand, 5wt%CeO2/Hal/Cur nanoparticles enhanced the uptake of curcumin in comparison to free curcumin. Overall, pegylated CeO2/Silica nano formulation demonstrated an effective carrier to cisplatin for potential treatment of breast cancer.
Entomopathogenic fungi and their biological control of Tetranychus urticae: Two-spotted spider mites
(2023) Khamis Al-Zahrani, Jawaher; Amira Alabdalall; Aly Osman, Mohamed; Aldakheel, Lena A.; Faisal AlAhmady, Nada; Aldakeel, Sumayh A.; J. Francis Borgio; Francis Borgio, J.; ElNaggar, Medhat A.; Alabdallah, Nadiyah M.; Almustafa, Mona M.
The two-spotted spider mite (TSSM) Tetranychus urticae, is regarded as one of the most dangerous pests responsible for great losses in most of agricultural crops. It is a persistent pest in Saudi Arabia, especially in greenhouses where T. urticae is primarily controlled by chemical pesticides. The main problem for the two-spotted spider mites is its high resistance to pesticides and high fertility rate. In the long term, chemical pesticides cause health problems and economic losses, so it was necessary to search for a safe alternative method for human health and the environment. One of these alternative methods was the selection of plant varieties resistant to the TSSM, in addition to biological control that includes mites or predatory insects and entomopathogenic fungi. The growth, reproduction, and life-table parameters of T. urticae were examined in a laboratory setting with a 16L:8D photoperiod at 28 ± 1 °C and 65 ± 5% RH, in the presence of three major members of Family: Solanaceae tomato, eggplant, and pepper. Pepper was shown to be less conducive to T. urticae growth and reproduction compared to eggplant and tomato. Tetranychus urticae proceeded through all five stages of its life cycle (egg, larva, protonymph, deutonymph, and adult) on tested solanaceous plants, and these plants significantly influenced its growth, reproduction, and Life-table parameters. Additionally, entomopathogenic fungi have been used against insects that have proven highly effective in controlling and reducing the density of two-spotted spider mites. Eight fungi were isolated from 80 insect and mite samples collected from several Saudi Arabia regions. Analysis of the 18S rRNA sequences revealed that the fungal strains identified as Beauveria bassiana, Fusarium sp. F. equiseti, F. oxysporium, Scopulariopsis brevicaulis1, S. brevicaulis2, Aspergillus sclerotiorum, and Penicillium citrinum. The ability of isolated fungi to secrete enzymes degrading the two-spotted spider mite cuticle, namely lipase, protease, and chitinase, were studied.
YBCO polycrystal co-added with BaTiO3 and WO3 nanoparticles: Fluctuation induced conductivity and pseudogap studies
(2023) Hannachi, E.; Slimani, Y.; Munirah Abdullah Almessiere; Yassine Slimani; Abdulhadi Baykal; Petrenko, E. V.; Kurbanov, U.; Ben Azzouz, F.; Solovjov, A. L.; Baykal, A.
We report the effect of the addition of BaTiO3 and WO3 nanoparticles on the pseudogap and excess conductivity of YBCO polycrystal. The excess conductivity analysis showed that the experimental data of pure and sample added with low amount of WO3 and BaTiO3 were perfectly described by the 2D Maki-Thompson (MT) and 3D Aslamazov-Larkin (AL) models. A sharp decrease in excess conductivity was obtained for samples added with high amount of nanoparticles where the analysis indicated the presence of the AL contribution and Lawrence-Doniach (LD) models. The pseudogap (PG) results showed that the value of Tpair (the temperature at which local pairs are transformed from strongly bound bosons into the fluctuating Cooper pairs) increased from around 117 K for the pure sample to around 187 K for sample co-added with low amount of nanoparticles. The pseudogap Δ*(TG) reduced from 230.9 K (for pure sample) to 223.4 K (for added sample).
Development of loop-mediated isothermal amplification (LAMP) assays using five primers reduces the false-positive rate in COVID-19 diagnosis
(2023) Galyah Alhamid; Ebtesam Al-Suhaimi; Al-Suhaimi, Ebtesam
The reverse-transcription loop-mediated isothermal amplification (RT-LAMP) is a cheaper and faster testing alternative for detecting SARS-CoV-2. However, a high false-positive rate due to misamplification is one of the major limitations. To overcome misamplifications, we developed colorimetric and fluorometric RT-LAMP assays using five LAMP primers, instead of six. The gold-standard RT-PCR technique verified the assays' performance. Compared to other primer sets with six primers (N, S, and RdRp), the E-ID1 primer set, including five primers, performed superbly on both colorimetric and fluorometric assays. The sensitivity of colorimetric and fluorometric assays was 89.5% and 92.2%, respectively, with a limit of detection of 20 copies/µL. The colorimetric RT-LAMP had a specificity of 97.2% and an accuracy of 94.5%, while the fluorometric RT-LAMP obtained 99% and 96.7%, respectively. No misamplification was evident even after 120 min, which is crucial for the success of this technique. These findings are important to support the use of RT-LAMP in the healthcare systems in fighting COVID-19.
Therapeutic Intervention for Various Hospital Setting Strains of Biofilm Forming Candida auris with Multiple Drug Resistance Mutations Using Nanomaterial Ag-Silicalite-1 Zeolite
(2022) Aldossary, Hanan A.; Ebtesam Abdullah Al-Suhaimi; Jermy, B. Rabindran; AlJindan, Reem; Aldayel, Afra; AbdulAzeez, Sayed; Akhtar, Sultan; Khan, Firdos Alam; Borgio, J. Francis; Al-Suhaimi, Ebtesam Abdullah
Candida auris (C. auris), an emerging multidrug-resistant microorganism, with limited therapeutical options, is one of the leading causes of nosocomial infections. The current study includes 19 C. auris strains collected from King Fahd Hospital of the University and King Fahad Specialist Hospital in Dammam, identified by 18S rRNA gene and ITS region sequencing. Drug-resistance-associated mutations in ERG11, TAC1B and FUR1 genes were screened to gain insight into the pattern of drug resistance. Molecular identification was successfully achieved using 18S rRNA gene and ITS region and 5 drug-resistance-associated missense variants identified in the ERG11 (F132Y and K143R) and TAC1B (H608Y, P611S and A640V) genes of C. auris strains, grouped into 3 clades. The prophylactic and therapeutic application of hydrothermally synthesized Ag-silicalite-1 (Si/Ag ratio 25) nanomaterial was tested against the 3 clades of clinical C. auris strains. 4wt%Ag/TiZSM-5 prepared using conventional impregnation technique was used for comparative study, and nano formulations were characterized using different techniques. The antibiofilm activity of nanomaterials was tested by cell kill assay, scanning electron microscopy (SEM) and light microscopy. Across all the clades of C. auris strains, 4 wt%Ag/TiZSM-5 and Ag-silicalite-1 demonstrated a significant (p = 1.1102 × 10−16) inhibitory effect on the biofilm’s survival rate: the lowest inhibition value was (10%) with Ag-silicalite-1 at 24 and 48 h incubation. A profound change in morphogenesis in addition to the reduction in the number of C. auris cells was shown by SEM and light microscopy. The presence of a high surface area and the uniform dispersion of nanosized Ag species displays enhanced anti-Candida activity, and therefore it has great potential against the emerging multidrug-resistant C. auris.
Nanogenerator-Based Sensors for Energy Harvesting From Cardiac Contraction
(2022) Al-Suhaimi, Ebtesam Abdullah; Meneerah A. Aljafary; Alfareed,Tahani M.; Hussah Alshwyeh; Alhamid,Galyah Mohammed; Sonbol,Bayan; Almofleh,Atheel; Galyah Alhamid; Reham Altwayan; Alharbi,Jamilah Naif; Noha Mubarak Binmahfooz; Alhasani,Eman Saleh; Tahani Alfareed; Atheel Awad Almofleh; lardhi,Amer A.; Baykal,Abdulhadi; Homeida,A. M.
Biomedical electric devices provide great assistance for health and life quality. However, their maintainable need remains a serious issue for the restricted duration of energy storage. Therefore, scientists are investigating alternative technologies such as nanogenerators that could harvest the mechanical energy of the human heart to act as the main source of energy for the pacemaker. Cardiac contraction is not a source for circulation; it utilizes body energy as an alternative energy source to recharge pacemaker devices. This is a key biomedical innovation to protect patients’ lives from possible risks resulting from repeated surgery. A batteryless pacemaker is possible via an implantable energy collecting tool, exchanging the restriction of the current batteries for a sustainable self-energy resource technique. In this context, the physiology of heart energy in the preservation of blood distribution pulse generation and the effects of cardiac hormones on the heart’s pacemaker shall be outlined. In this review, we summarized different technologies for the implantable energy harvesters and self-powered implantable medical devices with emphasis on nanogenerator-based sensors for energy harvesting from cardiac contraction. It could conclude that recent hybrid bio-nanogenerator systems of both piezoelectric and triboelectric devices based on biocompatible biomaterials and clean energy are promising biomedical devices for harvesting energy from cardiac and body movement. These implantable and wearable nanogenerators become self-powered biomedical tools with high efficacy, durability, thinness, flexibility, and low cost. Although many studies have proven their safety, there is a need for their long-term biosafety and biocompatibility. A further note on the biocompatibility of bio-generator sensors shall be addressed.
Shared Decision-Making: A Cross-Sectional Study Assessing Patients Awareness and Preferences in Saudi Arabia
(2022) Aljaffary, A.; Mona Aljuwair; Sumaiah Alrawiai; Duaa Aljabri; Aljuwair, M.; Bayan Hariri; Aljabri, D.; Fatimah Alsheddi; Hariri, B.; Alumran, A.; Rayanah Al-Mutairi
BACKGROUND AND AIM: Shared decision-making (SDM) has become broadly accepted during the consultation, especially when there are many options of treatment. This study aims to assess patients' levels of awareness and preferences of SDM in Saudi Arabia. METHODS: This is a cross-sectional study targeting patients in Saudi Arabia. Two validated questionnaires were used, the first validated questionnaire focuses on measuring knowledge, attitude and experiences of shared-decision making. The second questionnaire is the the Autonomy-Preference-Index focusing on patients' preferences for being involved in SDM. Relevant items to the study aim were chosen and translated into Arabic. Psychometric testing was conducted for Arabic and English versions and tested for content and face validity. The questionnaire administered online via social media channels, between February 2021 and May 2021. A total of 411 respondents completed the questionnaire. RESULTS: The findings showed a positive association between awareness and preferences of SDM among patients in Saudi Arabia. In the awareness of the SDM domain, females reported higher scores than male participants (t = -4.504, P < 0.001). Saudis reported higher scores in their awareness of SDM than non-Saudis (t = 2.569, P = 0.011). Participants without health insurance reported higher scores in their awareness of SDM than those insured (t = -2.130, P = 0.034). Participants with degree have higher knowledge levels than participants with no degree (f = 10.034, P < 0.001). Females reported higher scores in their preferences of SDM than the male (t = -2.099, P = 0.036). Participants who visited private health-care settings in their last clinical encounter reported higher preferences of SDM than participants who received care in other settings (f = 2.653, P = 0.048). CONCLUSION: The study concludes that the more aware a patient is, the more likely they prefer SDM practice. This finding can support health-care policymakers in developing SDM policies that enhance patient-centered care.
Colorimetric and fluorometric reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay for diagnosis of SARS-CoV-2
(2022) Alhamid, Galyah; Tombuloglu, Huseyin; Motabagani, Dalal; Motabagani, Dana; Rabaan, Ali A.; Unver, Kubra; Dorado, Gabriel; Al-Suhaimi, Ebtesam; Unver, Turgay
The coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has caused millions of infections and deaths worldwide since it infected humans almost 3 years ago. Improvements of current assays and the development of new rapid tests or to diagnose SARS-CoV-2 are urgent. Reverse transcription loop-mediated isothermal amplification (RT-LAMP) is a rapid and propitious assay, allowing to detect both colorimetric and/or fluorometric nucleic acid amplifications. This study describes the analytical and clinical evaluation of RT-LAMP assay for detection of SARS-CoV-2, by designing LAMP primers targeting N (nucleocapsid phosphoprotein), RdRp (polyprotein), S (surface glycoprotein), and E (envelope protein) genes. The assay’s performance was compared with the gold standard RT-PCR, yielding 94.6% sensitivity and 92.9% specificity. Among the tested primer sets, the ones for S and N genes had the highest analytical sensitivity, showing results in about 20 min. The colorimetric and fluorometric comparisons revealed that the latter is faster than the former. The limit of detection (LoD) of RT-LAMP reaction in both assays is 50 copies/µl of the reaction mixture. However, the simple eye-observation advantage of the colorimetric assay (with a color change from yellow to red) serves a promising on-site point-of-care testing method anywhere, including, for instance, laboratory and in-house applications.
Scalable, Quasi-Solid-State Bio-polymer Hydrogel Electrolytes for High-Performance Supercapacitor Applications
(2022) Atheel Almofleh; AMEERAH NASSER ALI ALQARNI; Bozkurt, Ayhan; Iqbal, Arfa; Asiri, Sarah M.; Alqarni, Ameerah N.; Almofleh, Atheel
The development of eco-friendly, quasi-solid-state bio-polymer hydrogel electrolytes has become one of the challenging issues in energy storage. The assembly of safer devices has still been the key to be addressed for safety reasons. The present work reports the synthesis of bio-polymer electrolytes using sodium carboxy methyl cellulose (C)/citric acid (CA) support, which was further intercalated by Hibiscus sabdariffa (H), at various fractions. Stable and scalable blends were produced, and the ion transport was effectively enhanced via insertion of H, which occurred through Na+ and H3O+ ions from the corresponding “host and guest”, where no external salt as ion source was inserted. The results showed that H in the hydrogel improved the ionic conductivity while maintaining the homogeneity and electrochemical stability. CCAH was coated on the carbon composite electrodes, and the devices were assembled, followed by experimental analysis under ambient conditions. The device exhibited excellent charge/discharge performance over 10,000 cycles with a specific capacitance of 442 F g–1. In addition, the device offers a superior energy density of 72 W h kg–1 at a power density of 331 W kg–1. Using non-toxic quasi-solid-state bio-polymer electrolyte hydrogels in devices may pave the way for safe usage in emerging wearable electronics and energy storage systems.
SARS-CoV-2 detection methods: A comprehensive review
(2022) Galyah Alhamid; Ebtesam Al-Suhaimi; Rabaan, Ali A.; Al-Suhaimi, Ebtesam
The ongoing novel COVID-19 has remained the center of attention, since its declaration as a pandemic in March 2020, due to its rapid and uncontrollable worldwide spread. Diagnostic tests are the first line of defense against the transmission of this infectious disease among individuals, with reverse-transcription quantitative polymerase chain reaction (RT-qPCR) being the approved gold standard for showing high sensitivity and specificity in detecting SARS-CoV-2. However, alternative tests are being invested due to the global demand for facilities, reagents, and healthcare workers needed for rapid population-based testing. Also, the rapid evolution of the viral genome and the emergence of new variants necessitates updating the existing methods. Scientists are aiming to improve tests to be affordable, simple, fast, and at the same time accurate, and efficient, as well as friendly user testing. The current diagnostic methods are either molecular-based that detect nucleic acids abundance, like RT-qPCR and reverse-transcription loop-mediated isothermal amplification (RT-LAMP); or immunologically based that detect the presence of antigens or antibodies in patients’ specimens, like enzyme-linked immunosorbent assay (ELISA), lateral flow assay (LFA), chemiluminescent immunoassay (CLIA), and neutralization assay. In addition to these strategies, sensor-based or CRISPR applications are promising tools for the rapid detection of SARS-CoV-2. This review summarizes the most recent updates on the SARS-CoV-2 detection methods with their limitations. It will guide researchers, epidemiologists, and clinicians in identifying a more rapid, reliable, and sensitive method of diagnosing SARS-CoV-2 including the most recent variant of concern Omicron.
Synthesis of Boron-Doped Non-Flammable Anhydrous Electrolytes for Flexible Quasi-Solid-State Supercapacitor Applications
(2022) Gunday, Seyda T; Omar Alagha; AMEERAH NASSER ALI ALQARNI; Iqbal, Arfa; Almofleh, Atheel; Alqarni, Ameerah N; Anil, Ismail; Alagha, Omar; Bozkurt, Ayhan
The quasi-solid-state electrolytes for flexible energy storage devices have indicated a great advancement during the last decade. However, further progress is still required to resolve non-flammability issues, high ionic conductivity, as well as electrochemical stability. Herein, we designed a new complex gel electrolyte with glycerol (Gly)/boric acid (BA) to address the non-flammability and maintained high conductivity by doping with potassium hydroxide (KOH). The Gly/3KOH/3BA combination was the optimum composition in terms of stability as well as hierarchical array for improved ionic conductivity to 2.9 × 10–3 S cm–1. Flexible electrochemical double-layer supercapacitors were assembled by using carbon composite electrodes, and the device provided a specific capacitance of 327 F g–1 at 1 A g–1. A remarkable cyclic stability of 93.4% capacitive performance is maintained after 10,000 cycles. The device indicated a specific energy of 45.4 W h kg–1 at a power of 920 W kg–1. Highly flexible devices constructed by using boron-incorporated gel electrolytes can provide a new strategy to assemble flexible devices for wearable electronics.
Structural and magnetic properties of hydrothermally synthesized Bi-substituted Ni–Co nanosized spinel ferrites
(2022) Ameerah, N. Alqarni; Munirah Almessiere; Murat Sertkol; M. Sertkol; Sagar, E. Shirsath; N. Tashkandi; A. Baykal
In this study, the structural, morphological, and magnetic properties of hydrothermally synthesized Co0.5Ni0.5BixFe2-xO4 (x=0.00–0.10) nanosized spinel ferrites, (CoNiBiFO (x=0.00–0.10) NSFs), were investigated. The formation of CoNiBiFO NSFs phase was confirmed by X-ray diffraction (XRD). Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed the morphology of the NSFs. Magnetization revealed that undoped Co0.5Ni0.5Fe2O4 and Co0.5Ni0.5BixFe2-xO4 NSFs (except with x = 0.04) exhibit ferrimagnetic magnetism at 300 K. Only the hysteresis loops recorded from Co0.5Ni0.5Bi0.04Fe1.96O4 NSFs have superparamagnetic characteristics. Mixed Co0.5Ni0.5Fe2O4 NSFs have maximum remnant magnetization (Mr) of 23.5 emu/g, maximum saturation magnetization (MS) of 63.38 emu/g, and maximum magneton number (nB) 2.66 μB. However, Co0.5Ni0.5Bi0.04Fe1.96O4 NSFs have minimum MS of 28.25 emu/g and minimum nB as 1.22 μB among Bi3+ doped and undoped samples. The coercivity (HC) of undoped Co0.5Ni0.5Fe2O4 NSFs is 656 Oe. However, the Bi3+ ion-doped samples have a wide range of HC values between 101 Oe and 1038 Oe. The squareness ratios are in the range of 0.092–0.418 and multi-domain structure is assigned for all types of samples. The measured positive exchange bias (HE) magnitudes are 268 Oe and 290 Oe, respectively. Hysteresis loops recorded at 10 K proved that the products are ferrimagnetic. These coercivities showed that all the samples are magnetically harder at low temperatures. Positive HE values of 165 Oe and 297 Oe were measured from the nanoparticles (NPs) with x = 0.08 and x = 0.10 at 10 K. The SQR of the Co0.5Ni0.5Bi0.04Fe1.96O4 sample at 10 K is almost equal to the critical value of 0.5, and a single domain structure with uniaxial symmetry can be attributed for this sample. The other samples have SQRs in the range of 0.632–0.782 and multi-domain wall structure is assigned for them at 10 K.
Emerging Status of Multidrug-Resistant Bacteria and Fungi in the Arabian Peninsula
(2021) J. F. R. Borgio, A. S.; Sonbol, B.; Alhamid, G.; Almandil, N. B.; AbdulAzeez, S.
Simple Summary The incidence and developing status of multidrug-resistant bacteria and fungi, as well as their related mortality, is reviewed by a systematic published literature search from nine countries in the Arabian Peninsula. In order to analyse the emerging status and mortality, a total of 382 research articles were selected from a comprehensive screening of 1705 papers. More than 850 deaths reported since 2010 in the Arabian Peninsula due to the infection of multidrug-resistant bacteria and fungi. Multidrug-resistant bacteria Acinetobacter baumannii, Mycobacterium tuberculosis, Staphylococcus aureus, and fungi Candida auris are the most prevalent and causing high deaths. To control these infections and associated deaths in the Arabian Peninsula, continuous preventive measures, accurate methods for early diagnosis of infection, active surveillance, constant monitoring, developing vaccines, eradicating multidrug resistance modulators, and data sharing among countries are required. We aimed to identify the prevalence and emerging status of multidrug-resistant bacteria and fungi and their associated mortality in nine countries in the Arabian Peninsula. Original research articles and case studies regarding multidrug-resistant bacteria and fungi in the Arabian Peninsula, published during the last 10 years, were retrieved from PubMed and Scopus. A total of 382 studies were included as per the inclusion and exclusion criteria, as well as the PRISMA guidelines, from a thorough screening of 1705 articles, in order to analyse the emerging status and mortality. The emerging nature of >120 multidrug-resistant (MDR) bacteria and fungi in the Arabian Peninsula is a serious concern that requires continuous monitoring and immediate preventive measures. More than 50% (n = 453) of multidrug-resistant, microbe-associated mortality (n = 871) in the Arabian Peninsula was due to MDR Acinetobacter baumannii, Mycobacterium tuberculosis and Staphylococcus aureus infection. Overall, a 16.51% mortality was reported among MDR-infected patients in the Arabian Peninsula from the 382 articles of this registered systematic review. MDR A. baumannii (5600 isolates) prevailed in all the nine countries of the Arabian Peninsula and was one of the fastest emerging MDR bacteria with the highest mortality (n = 210). A total of 13,087 Mycobacterium tuberculosis isolates were reported in the region. Candida auris (580 strains) is the most prevalent among the MDR fungal pathogen in the Arabian Peninsula, having caused 54 mortalities. Active surveillance, constant monitoring, the development of a candidate vaccine, an early diagnosis of MDR infection, the elimination of multidrug resistance modulators and uninterrupted preventive measures with enhanced data sharing are mandatory to control MDR infection and associated diseases of the Arabian Peninsula. Accurate and rapid detection methods are needed to differentiate MDR strain from other strains of the species. This review summarises the logical relation, prevalence, emerging status and associated mortality of MDR microbes in the Arabian Peninsula.
Superconducting properties of YBCO bulk co-embedded by nano-BaTiO3 and WO3 particles
(2021) S. A. S. Alotaibi, Y.Almessiere, M. A.Hannachi, E.Al-qwairi, F. O.Iqbal, M.Ben Azzouz, F.Yasin, G.; Fatimah Omar Saeed Al-alqwai; M.A. Almessiere; Faten Ben Azzouz
The combined effect of the addition of different weight percentages of nano-BaTiO3/WO3 particles, synthesized through a solid-state reaction route in bulk YBCO superconductor was studied. The examination by X-ray diffraction (XRD) showed that the samples crystallize into the orthorhombic structure. The orthorhombic distortion reduced with increasing the content of BTO and WO3 nanoparticles. The diminution of the orthorhombic distortion is followed by a significant alteration of critical transition temperature (T-co) at high addition level. The variation in crystallite size, electrical transport, magnetic field dependence of critical current density (J(c)), and flux-pinning force (F-p) of YBCO with various amounts of BTO, WO3 nanoparticles were studied in detail. The self-field critical current density (J(c)) increases to a maximum value of 0.32 x 10(4) A cm(-2) for the 0.05 wt% co-addition of nano-BTO/WO3 particles. The factor boosting in this content was found to reach up to 45 when compared to the pure sample in the entire applied magnetic field. The enhancement of J(c) values in the 0.05 wt% added sample was attributed to the presence of high-efficiency crystal defects that act as artificial pinning centers, formed due to the BTO/WO3 nanoparticles co-addition. Also, the pinning force density was enhanced by the co-addition of nano-BTO/WO3 particles in YBCO bulk superconductor and attained a maximum value of 1.5 MT.A.m(-2) at 77 K for x = 0.05 wt%.
Synergistic action of curcumin and cisplatin on spinel ferrite/hierarchical MCM-41 nanocomposite against MCF-7, HeLa and HCT 116 cancer cell line
(2021) Nora Khalid AlSudairi; Atheel Awad Almofleh; Tahani M. Alfareed; Vijaya Ravinayagam; Rubavathi Marimuthu
Background: Platinum-based drugs are widely used in cancer therapy, but are known for toxic side effects and resistance. Combinational drug delivery represents an effective chemotherapeutic strategy, but often leads to an increased toxicity. Aim of this study is to test the co-delivery of cisplatin with natural antioxidants on hierarchial porous large surface area hexagonal nanocarriers for synergistic action. Results: A series of structured mesoporous materials were impregnated with magnetic spinel ferrite (30% CuFe2O4) and then coated with curcumin (25% wt/wt). Mesosilicalite and MCM-41 with high curcumin release abilities were functionalized with cisplatin (5% wt/wt) for synergistic effect of combinational drugs. The cytotoxic efficiency of our nanocomposites was tested on cell viability of MCF7 (human breast cancer), human cervical cancer (HeLa), colorectal cancer (HCT116), and HFF (human foreskin fibroblasts) cell lines using the MTT cell viability assay. At a concentration of 0.1 mg/ml, CuFe2O4/mesosilicalite/curcumin/cisplatin resulted in 89.53% reduction in viability in MCF7, 94.03% in HeLa, 64% in HCT116 and 87% in HFF; whereas, CuFe2O4/MCM-41/curcumin/cisplatin resulted in 76% reduction in viability in MCF7, 64.46% in HeLa, 64% in HCT116 and 24% in HFF. The EC50 for CuFe2O4/mesosilicalite/curcumin/cisplatin was 81.23 mu g/ml in MCF7, 47.55 pg/ml in HeLa, 48.96 mu g/ml in HCT116 and 76.83 mu g/ml in HFF. The EC50 for CuFe2O4/MCM-41/curcumin/cisplatin was 72.51 mu g/ml in MCF7, 58.6 mu g/ml in HeLa, 62.58 mu g/ml in HCT116 and 154.2 mu g/ml in HFF. Furthermore, cells treated with both nanocomposites had a high number of cleaved Caspase 3-positive cells suggesting that the reduction in cell viability was triggered by activating the apoptotic signaling pathway. Conclusion: Our results show that CuFe2O4/MCM-41/curcumin/cisplatin is a better candidate for combinational drug therapy due to its lowest EC50 value and the wider difference in EC50 (a fold change) between cancerous and non-cancerous cell line.
The development of novel cost-effective bio-electrolyte with glycerol host for carbon-based flexible supercapacitor applications
(2022) A. C. Almofleh, E.Bozkurt, A.
Extensive attention has been given for the fabrication of stable and cost-effective electrolytes materials for wearable energy storage systems. Herein, glycerol (Gly) and H3PO4 (P) based bio-electrolyte for electrical double layer capacitance (EDLC) was produced and then converted to redox-mediated gel bio-electrolytes via doping with cobalt ions (Co) at various compositions to form glycerol-H3PO4-Co (GlyPCoX; X: 1%, 3%, 5%, 10% w/w). The gel electrolyte forms a hierarchical framework for effective ion conduction between the pores of the carbon composite electrodes that is triggered by bias during charging and discharging processes. The supercapacitors (SCs) were assembled with activated carbon-based composite electrodes and device performances were tested according to redox-mediated electrolyte compositions. Remarkable device performance was obtained from the Gly, which contained 5 M H3PO4 (P5) and 5% Co (Co5), (GlyP5Co5) and showed a specific capacitance of 349 F g(-1). The corresponding specific energy and specific power were calculated as 47 and 420 W kg(-1). Excellent operational stability (91%) was obtained after 15 000 charge/discharge cycles. In addition, the electrolyte is cost effective, retained extraordinary performance during galvanostatic charge-discharge (GCD), and successfully powered light-emitting diode (LED) device (1-4 cm) at various bending angles. Thus, the gel electrolyte has excellent stability and flexibility for use in wearable energy storage systems.
Investigation of transport properties, flux pinning mechanisms and fluctuations induced conductivity of SiO2 nanoparticles doped YBa2Cu3O7-d thick films on silver substrates
(2022) Yassine Slimani , Essia Hannachi , Munirah A. Almessiere , Haya S. Aldosari , Sarah A. Alotaibi , Faten {Ben Azzouz
In this study, we examined the pinning mechanism and fluctuations induced conductivity, and we report the superconducting critical parameters variation of fine SiO2 nanoparticles added YBa2Cu3O7−d (Y123) composite thick films of ∼100 μm in thicknesses on Ag substrate. Composite films (Y123 + x SiO2)/Ag were produced by the solid-state reaction process. Here, x = 0.00 and 0.01 wt% content of SiO2 nanoparticles (12 nm in diameter) were considered. The X-ray powder diffraction (XRD) together with Rietveld refinement and the scanning electron microscopy (SEM) were used to survey the structure and the morphology of thick films. Both composite films reveal a dense granular structure and similar compositions in phases. A small quantity of fine SiO2 particles intensifies the critical current density versus magnetic field Jc(H) and gives more weight to the strong pinning component of the Jc. Some important critical physical parameters of the composite films were obtained from the fluctuations induced conductivity analyses. The electrical conductivity was deduced from the electrical resistivity measurements and explained through Aslamazov–Larkin model. A small quantity of fine SiO2 particles upgrade the superconducting features, particularly the lower and the upper critical magnetic field (Bc1 and Bc2) at temperature 0 K.
Emerging trends in the application of gold nanoformulations in colon cancer diagnosis and treatment
(2021) Razan Aldahhan
Colorectal cancer is one of the most aggressive types of cancer with about two million new cases and one million deaths in 2020. The side effects of the available chemotherapies and the possibility of developing resistance against treatment highlight the importance of developing new therapeutic options. The development in the field of nanotechnology have introduced the application of nanoparticles (NPs) as a promising approach in the diagnosis and treatments of colorectal cancer and other types of cancer. Gold nanoparticles (AuNPs) are currently one of the most studied materials as they possess unique tunable properties allowing them to play a role in colorectal cancer bioimaging, diagnosis, and therapy. The high surface-to-volume ratio of AuNPs mediates their utilization in drug delivery as well as functionalization to provide specific targeting. Moreover, depending on their physical properties (size, shape), AuNPs can be modified to fit the intended application. However, there are contradictory results around the pharmacokinetics of AuNPs including their biodistribution, clearance, and toxicity. This variation of opinions is most likely due to the development of different AuNPs that vary in shape, size, and surface chemistry, in addition to the conditions under which each research was carried out. The conflicting data represent a challenge in the clinical use of AuNPs suggesting the need to understand the toxicity, fate, and long-term exposure of AuNPs in vivo. Thus, there is an unmet need for the establishment of a publicly available data base for extensive analysis. In this review, we discuss the recent advances in AuNP applications in the treatment and diagnosis of colorectal cancer, mechanisms of action, and clinical challenges.

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