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101.
Mohammed S. Alqahtani Mohamed Abbas Mohammed Abdulmuqeet Abdullah S. Alqahtani Mohammad Y. Alshahrani Abdullah Alsabaani Murugan Ramalingam 《Materials》2022,15(14)
The COVID-19 pandemic has the tendency to affect various organizational paradigm alterations, which civilization hasyet to fully comprehend. Personal to professional, individual to corporate, and across most industries, the spectrum of transformations is vast. Economically, the globe has never been more intertwined, and it has never been subjected to such widespread disruption. While many people have felt and acknowledged the pandemic’s short-term repercussions, the resultant paradigm alterations will certainly have long-term consequences with an unknown range and severity. This review paper aims at acknowledging various approaches for the prevention, detection, and diagnosis of the SARS-CoV-2 virus using nanomaterials as a base material. A nanostructure is a material classification based on dimensionality, in proportion to the characteristic diameter and surface area. Nanoparticles, quantum dots, nanowires (NW), carbon nanotubes (CNT), thin films, and nanocomposites are some examples of various dimensions, each acting as a single unit, in terms of transport capacities. Top-down and bottom-up techniques are used to fabricate nanomaterials. The large surface-to-volume ratio of nanomaterials allows one to create extremely sensitive charge or field sensors (electrical sensors, chemical sensors, explosives detection, optical sensors, and gas sensing applications). Nanowires have potential applications in information and communication technologies, low-energy lightning, and medical sensors. Carbon nanotubes have the best environmental stability, electrical characteristics, and surface-to-volume ratio of any nanomaterial, making them ideal for bio-sensing applications. Traditional commercially available techniques have focused on clinical manifestations, as well as molecular and serological detection equipment that can identify the SARS-CoV-2 virus. Scientists are expressing a lot of interest in developing a portable and easy-to-use COVID-19 detection tool. Several unique methodologies and approaches are being investigated as feasible advanced systems capable of meeting the demands. This review article attempts to emphasize the pandemic’s aftereffects, utilising the notion of the bullwhip phenomenon’s short-term and long-term effects, and it specifies the use of nanomaterials and nanosensors for detection, prevention, diagnosis, and therapy in connection to the SARS-CoV-2. 相似文献
102.
Khalil B. Ramadi Yassir A. Mohamed Ashraf Al-Sbiei Saeeda Almarzooqi Ghada Bashir Aisha Al Dhanhani 《Nanotoxicology》2016,10(8):1061-1074
Nanoparticles (NPs) are increasingly being commercialized for use in biomedicine. NP toxicity following acute or chronic exposure has been described, but mechanistic insight into this process remains incomplete. Recent evidence from in vitro studies suggested a role for NLRP3 in NP cytotoxicity. In this study, we investigated the effect of systemic administration of composite inorganic NP, consisting of Ag:Cu:B (dose range 1–20?mg/kg), on the early acute (4–24?h post-exposure) and late phase response (96?h post-exposure) in normal and NLRP3-deficient mice. Our findings indicate that systemic exposure (≥2?mg/kg) was associated with acute liver injury due to preferential accumulation of NP in this organ and resulted in elevated AST, ALT and LDH levels. Moreover, within 24?h of NP administration, there was a dose-dependent increase in intraperitoneal neutrophil recruitment and upregulation in gene expression of several proinflammatory mediators, including TNF-α, IL-1β and S100A9. Histological analysis of liver tissue revealed evidence of dose-dependent hepatocyte necrosis, increase in sinusoidal Kupffer cells, lobular granulomas and foci of abscess formation which were most pronounced at 24?h following NP administration. NP deposition in the liver led to a significant upregulation in gene expression of S100A9, an endogenous danger signal recognition molecule of phagocytes, IL-1β and IL-6. The extent of proinflammatory cytokine activation and hepatotoxicity was significantly attenuated in mice deficient in the NLRP3 inflammasome, demonstrating the critical role of this innate immune system recognition receptor in the response to NP. 相似文献
103.
Karrout Y Neut C Siepmann F Wils D Ravaux P Deremaux L Flament MP Dubreuil L Lemdani M Desreumaux P Siepmann J 《The Journal of pharmacy and pharmacology》2010,62(12):1676-1684
Objectives Film coatings based on blends of Eurylon 6 HP‐PG (a hydroxypropylated and pregelatinized high amylose starch) and ethylcellulose were to be evaluated as promising coating materials for site‐specific drug delivery to the colon of patients suffering from inflammatory bowel diseases. Methods Pellet starter cores containing 60% 5‐aminosalicylic acid were prepared by extrusion/spheronization and coated with different Eurylon 6 HP‐PG : ethylcellulose blends at various coating levels. Drug release was measured in media simulating the contents of the upper gastrointestinal tract (in the presence and absence of enzymes) as well as in media simulating the contents of the colon. Key findings 5‐Aminosalicylic acid release could effectively be suppressed in 0.1 N HCl and phosphate buffer pH 6.8, optionally containing pepsin or pancreatin, but occurred as soon as the pellets came into contact with culture medium inoculated with faecal samples from inflammatory bowel disease patients. This can be attributed to the partial degradation of the starch derivative by enzymes secreted by bacteria present in the colon of these patients. Conclusions The presented drug delivery system is adapted to the pathophysiological conditions in inflammatory bowel disease patients. Furthermore, drug release remained unaltered upon 1 year open storage. 相似文献
104.
Hammad Ahmed Shah Moncef L. Nehdi Muhammad Imtiaz Khan Usman Akmal Hisham Alabduljabbar Abdullah Mohamed Muhammad Sheraz 《Materials》2022,15(15)
Compressive strength (CS) and splitting tensile strength (STS) are paramount parameters in the design of reinforced concrete structures and are required by pertinent standard provisions. Robust prediction models for these properties can save time and cost by reducing the number of laboratory trial batches and experiments needed to generate suitable design data. Silica fume (SF) is often used in concrete owing to its substantial enhancements of the engineering properties of concrete and its environmental benefits. In the present study, the M5P model tree algorithm was used to develop models for the prediction of the CS and STS of concrete incorporating SF. Accordingly, large databases comprising 796 data points for CS and 156 data records for STS were compiled from peer-reviewed published literature. The predictions of the M5P models were compared with linear regression analysis and gene expression programming. Different statistical metrics, including the coefficient of determination, correlation coefficient, root mean squared error, mean absolute error, relative squared error, and discrepancy ratio, were deployed to appraise the performance of the developed models. Moreover, parametric analysis was carried out to investigate the influence of different input parameters, such as the SF content, water-to-binder ratio, and age of the specimen, on the CS and STS. The trained models offer a rapid and accurate tool that can assist the designer in the effective proportioning of silica fume concrete. 相似文献
105.
Mohamed A. Eldaly Mohamad A. AbdelHakim Rania S. Zaki Ayman F. El-Shiaty 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2013,251(3):661-665
Background
Cairo university hospitals are at the heart of Cairo with close proximity to Tahrir (Liberation) square and had received the vast majority of casualties during the Egyptian revolution. The aim of this study was to analyze the eye injuries during the uprising.Design
Retrospective cohort study.Methods
Data were obtained from patients’ paper records, interview with treating ophthalmologists, and whenever possible patients were interviewed and examined. An electronic medical template had been specially developed for recording these data. Main outcome measures were the flow of patients and their demographics, diagnoses, visual acuities pre and post interventions, investigations and management. Whenever required results were compared at 95 % confidence interval.Results
There were 184 patients (mean age 27.3?±?9.6 years) with 195 injured eyes of whom 96.7 % were males and 11 patients had both eyes injured. Seventy seven percent of patients had been admitted within 24 h of injury. Open globe injuries comprised 87 % of the eyes of which 147 eyes received 259 imaging investigations. The presenting visual acuities were worse than 3/60 in 72.5 % of eyes which were even worse post interventions and that was significantly dependent on the presenting vision. Wound repair was the primary intervention in 85 % of eyes while 50 % of the secondary interventions were vitrectomies.Conclusions
Presenting visual acuity is a valid prognostic factor in the setting of mass eye casualty. Management of open globe injuries continues to pose difficult challenges especially bilateral ones. 相似文献106.
107.
108.
109.
Meroditerpenoids and derivatives from the brown alga Cystoseira baccata and their antifouling properties 总被引:1,自引:0,他引:1
Mokrini R Mesaoud MB Daoudi M Hellio C Maréchal JP El Hattab M Ortalo-Magné A Piovetti L Culioli G 《Journal of natural products》2008,71(11):1806-1811
The brown alga Cystoseira baccata harvested along the Atlantic coasts of Morocco yielded seven new meroditerpenoids (1-4) and derivatives (5-7), whose chemical structures were elucidated mainly by 2D NMR and mass spectrometry. Surprisingly, for all these compounds, which possess a bicyclo[4.3.0]nonane ring system, a trans fusion of the bicyclic system was deduced by stereochemical studies even though such compounds isolated from Cystoseira species are known to have a typical cis orientation for the bridgehead methyls. The antifouling and antibacterial activities of compounds 1-5 and 7 were evaluated, as well as their toxicity toward nontarget species. Compounds 4, 5, and 7 showed antifouling activities against growth of microalgae, macroalgal settlement, and mussel phenoloxidase activity, while being nontoxic to larvae of sea urchins and oysters. 相似文献
110.
Fares F Badarneh K Abosaleh M Harari-Shaham A Diukman R David M 《Prenatal diagnosis》2008,28(3):236-241
BACKGROUND: Ashkenazi Jewish (AJ) population is at increased risk for several recessive inherited diseases. Therefore, carrier testing of AJ members is important in order to identify couples at risk of having offspring with an autosomal recessive disorder. METHODS: In the present study, a database containing the results of 28 410 genotyping assays was screened. Ten thousand seventy eight nonselected healthy members of the AJ population were tested for carrier status for the following diseases; Gaucher disease (GD), cystic fibrosis (CF), Familial dysautonomia (FD), Alpha 1 antitrypsin (A1AT), Mucolipidosis type 4 (ML4), Fanconi anemia type C (FAC), Canavan disease (CD), Neimann-Pick type 4 (NP) and Bloom syndrome (BLM). RESULTS: The results demonstrated that 635 members were carriers of one mutation and 30 members were found to be carriers of two mutations in the different genes related to the development of the above mentioned diseases. GD was found to have the highest carrier frequency (1:17) followed by CF (1:23), FD (1:29), A1AT (1:65), ML4 (1:67) and FAC (1:77). The carrier frequency of CD, NP and BLM was 1:82, 1:103 and 1:157, respectively. CONCLUSIONS: The frequency of the disease-causing mutations screened routinely among the AJ population indicated that there are rare mutations with very low frequencies. The screening policy of the disease-causing mutations should be reevaluated and mutations with a high frequency should be screened, while rare mutations with a lower frequency may be tested in partners of carriers. 相似文献