Displaying publications 61 - 80 of 186 in total

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  1. High-performance porous biochar from the pyrolysis of natural and renewable seaweed (Gelidiella acerosa) and its application for the adsorption of methylene blue
    Ahmed MJ, Okoye PU, Hummadi EH, Hameed BH
    Bioresour Technol, 2019 Apr;278:159-164.
    PMID: 30685620 DOI: 10.1016/j.biortech.2019.01.054
    A high-performance porous biochar adsorbent prepared by facile thermal pyrolysis of seaweed (Gelidiella acerosa) is reported. The textural characteristics of the prepared seaweed biochar (SWBC) and the performance in the adsorption of methylene blue (MB) dye were evaluated. The batch experiment for the adsorption of MB was conducted under different parameters, such as temperature, pH, and initial concentration of MB in the range of 25-400 mg/L. The developed SWBC exhibited a relatively high surface area, average pore size, and pore volume of 926.39 m2/g, 2.45 nm, and 0.57 cm3/g, respectively. The high surface area and pristine mineral constituents of the biochar promoted a high adsorption capacity of 512.67 mg/g of MB at 30 °C. The adsorption isotherm and kinetics data best fitted the Langmuir and pseudo-second-order equations. The results indicate that SWBC is efficient for MB adsorption and could be a potential adsorbent for wastewater treatment.
  2. Mesoporous-activated carbon prepared from chitosan flakes via single-step sodium hydroxide activation for the adsorption of methylene blue
    Marrakchi F, Ahmed MJ, Khanday WA, Asif M, Hameed BH
    Int J Biol Macromol, 2017 May;98:233-239.
    PMID: 28147233 DOI: 10.1016/j.ijbiomac.2017.01.119
    In this work, mesoporous-activated carbon (CSAC) was prepared from chitosan flakes (CS) via single-step sodium hydroxide activation for the adsorption of methylene blue (MB). CSAC was prepared using different impregnation ratios of NaOH:CS (1:1, 2:1, 3:1, and 4:1) at 800°C for 90min. The adsorption performance of CSAC was evaluated for MB at different adsorption variables, such MB initial concentrations (25-400mg/L), solution pH (3-11), and temperature (30-50°C). The adsorption isotherm data of CSAC-MB were well fitted to Langmuir model with a maximum adsorption capacity 143.53mg/g at 50°C. Best representation of kinetic data was obtained by the pseudo-second order model. CSAC exhibited excellent adsorption uptake for MB and can potentially be used for other cationic dyes.
  3. Mesoporous activated carbon prepared from NaOH activation of rattan (Lacosperma secundiflorum) hydrochar for methylene blue removal
    Islam MA, Ahmed MJ, Khanday WA, Asif M, Hameed BH
    Ecotoxicol Environ Saf, 2017 Apr;138:279-285.
    PMID: 28081490 DOI: 10.1016/j.ecoenv.2017.01.010
    Hydrothermal carbonization of biomass wastes presents a promising step in the production of cost-effective activated carbon. In the present work, mesoporous activated carbon (HAC) was prepared by the hydrothermal carbonization of rattan furniture wastes followed by NaOH activation. The textural and morphological characteristics, along with adsorption performance of prepared HAC toward methylene blue (MB) dye, were evaluated. The effects of common adsorption variables on performance resulted in a removal efficiency of 96% for the MB sample at initial concentration of 25mg/L, solution pH of 7, 30°C, and 8h. The Langmuir equation showed the best isotherm data correlation, with a maximum uptake of 359mg/g. The adsorbed amount versus time data was well fitted by a pseudo-second order kinetic model. The prepared HAC with a high surface area of 1135m(2)/g and an average pore size distribution of 35.5Å could be an efficient adsorbent for treatment of synthetic dyes in wastewaters.
  4. Microwave assisted digestion followed by ICP-MS for determination of trace metals in atmospheric and lake ecosystem
    Ahmed M, Chin YH, Guo X, Zhao XM
    J Environ Sci (China), 2017 May;55:1-10.
    PMID: 28477801 DOI: 10.1016/j.jes.2016.06.014
    The study of trace metals in the atmosphere and lake water is important due to their critical effects on humans, aquatic animals and the geochemical balance of ecosystems. The objective of this study was to investigate the concentration of trace metals in atmospheric and lake water samples during the rainy season (before and after precipitation) between November and December 2015. Typical methods of sample preparation for trace metal determination such as cloud point extraction, solid phase extraction and dispersive liquid-liquid micro-extraction are time-consuming and difficult to perform; therefore, there is a crucial need for development of more effective sample preparation procedure. A convection microwave assisted digestion procedure for extraction of trace metals was developed for use prior to inductively couple plasma-mass spectrometric determination. The result showed that metals like zinc (133.50-419.30μg/m(3)) and aluminum (53.58-378.93μg/m(3)) had higher concentrations in atmospheric samples as compared to lake samples before precipitation. On the other hand, the concentrations of zinc, aluminum, chromium and arsenic were significantly higher in lake samples after precipitation and lower in atmospheric samples. The relationship between physicochemical parameters (pH and turbidity) and heavy metal concentrations was investigated as well. Furthermore, enrichment factor analysis indicated that anthropogenic sources such as soil dust, biomass burning and fuel combustion influenced the metal concentrations in the atmosphere.
  5. Esophageal cancer epidemiology, diagnosis, and management in Sudan - A review
    Musa IH, Musa TH, Musa HH, Ahmed ME
    Med J Malaysia, 2021 09;76(5):691-697.
    PMID: 34508376
    INTRODUCTION: In Sudan, cancer a common health challenge, is the leading cause of death after malaria and viral pneumonia. The aim of the review is to determine the risk factors associated with esophageal cancer (EC) among Sudanese population.

    METHODS: All published online data concerning EC epidemiology, diagnosis, and management in Sudan were studied.

    RESULTS: The prevalence of EC in Sudan is ranked fourth among cancer types in males and fifth in females. The squamous cell carcinoma is more predominant than adenocarcinoma. The dietary, dysplasia and teeth loss, cigarette smoking, age, sex, GERD, genetic and environmental interactions remain a risk for developing EC in clinical practice. A significant challenge for treatment is that most of EC patients were often diagnosed in advanced stages due to the lack of early clinical symptoms. Management of EC depends on patient fitness and tumor stage, endoscopic removal was used for early tumors, while chemotherapy, chemo-radiotherapy, surgical resection, or combinations of these were used for advanced tumors. Despite improvements in the management and treatment of EC patients, the general outcome remains very poor. Furthermore, using molecular techniques to better understand the etiology of EC, it may assist in identifying complicated and critical issues and improve therapy towards a new treatment strategy.

    CONCLUSION: The remarkable factors associated with EC among Sudanese are geographical variation, environmental factors, ethnic differences, dietary and social habits.

  6. Low-temperature solution-processed flexible solar cells based on (In,Ga)N nanocubes
    Qaeed MA, Ibrahim K, Saron KM, Ahmed MA, Allam NK
    ACS Appl Mater Interfaces, 2014 Jul 9;6(13):9925-31.
    PMID: 24937197 DOI: 10.1021/am502217b
    Indium gallium nitride nanocubes were syntheized via a low-temperature chemical route. Energy-dispersive X-ray spectroscopy and X-ray diffraction analyses confirmed the successful fabrication of (In,Ga)N with various indium mole fractions. The bandgap of the material was tunded as a function of the indium content. The fabricated nanocubes showed a deep level photoluminescence emission at 734 nm as well as in the visible region at 435-520 nm. The Hall effect measurements showed the hole concentration to constantly increase from 6.2 × 10(16) to 2.3 × 10(18) cm(-3), while the hole mobility to decrease from 0.92 to 0.1 cm(2) /(V s) as the doping ratio increases from 0.005 to 0.025 cm(-3). The solar cell device made of nanocubes film containing 0.4 indium on flexible substrates showed a short-circuit current density of 12.47 mA/cm(2) and an open-circuit voltage (Voc) of 0.48 V with 54% fill factor. The relationship between Voc and indium content in the fabricated films was also investigated.
  7. In vivo anti-hyperglycemic activity of saliva extract from the tropical leech Hirudinaria manillensis
    Mohammed AA, Mohammad GA, Mohamed A, Mohamed A, Ahmed M
    Chin J Nat Med, 2013 Sep;11(5):488-93.
    PMID: 24359772 DOI: 10.1016/S1875-5364(13)60089-8
    The anticoagulant effect of leech saliva was traditionally employed in the treatment of diabetes mellitus complications such as peripheral vascular complications. This study was carried out to examine the effect of leech saliva extract (LSE) on blood glucose levels in alloxan-induced diabetic rats. First, LSE was collected from leeches which were fed on a phagostimulatory solution. Second, total protein concentration was estimated using the Bradford assay. Third, diabetic rats were injected subcutaneously (sc) with LSE at doses of 500 and 1 000 μg·kg(-1) body weight (bw). Other diabetic rats were injected sc with insulin at doses of 10 and 20 U·kg(-1) bw. Another group was injected simultaneously with LSE (250 μg·kg(-1) bw) and insulin (10 U·kg(-1) bw). Fasting blood glucose (FBG) concentrations were monitored during a study period of eight hours at regular intervals. Findings showed that both doses of LSE resulted in a significant and gradual decrease in FBG starting from 10%-18% downfall after two hours of injection reaching the maximal reduction activity of 58% after eight hours. Remarkably, LSE was sufficient to bring the rats to a near norm-glycemic state. The high dose of insulin induced a severe hypoglycemic condition after 2-4 h of injection. The lower dose was able to decline FBG for 2-6 h in rats which became diabetic again after 8 h. On the other hand, the concurrent injection of low doses of LSE and insulin produced a hypoglycemic effect with all rats showing normal FBG levels. Taken together, these findings indicated that the subcutaneous injection of LSE of the medicinal Malaysian leech was able to provide better glycemic control compared with insulin. Moreover, the synergism between LSE and insulin suggests that LSE could be utilized as an adjuvant medication in order to reduce insulin dosage or to achieve better control of blood glucose.
  8. Fulltext New quinoxalinone inhibitors targeting secreted phospholipase A2 and α-glucosidase
    Alasmary FAS, Alnahdi FS, Ben Bacha A, El-Araby AM, Moubayed N, Alafeefy AM, et al.
    J Enzyme Inhib Med Chem, 2017 Dec;32(1):1143-1151.
    PMID: 28856929 DOI: 10.1080/14756366.2017.1363743
    Elevated blood glucose and increased activities of secreted phospholipase A2 (sPLA2) are strongly linked to coronary heart disease. In this report, our goal was to develop small heterocyclic compound that inhibit sPLA2. The title compounds were also tested against α-glucosidase and α-amylase. This array of enzymes was selected due to their implication in blood glucose regulation and diabetic cardiovascular complications. Therefore, two distinct series of quinoxalinone derivatives were synthesised; 3-[N'-(substituted-benzylidene)-hydrazino]-1H-quinoxalin-2-ones 3a-f and 1-(substituted-phenyl)-5H-[1,2,4]triazolo[4,3-a]quinoxalin-4-ones 4a-f. Four compounds showed promising enzyme inhibitory effect, compounds 3f and 4b-d potently inhibited the catalytic activities of all of the studied proinflammatory sPLA2. Compound 3e inhibited α-glucosidase (IC50 = 9.99 ± 0.18 µM); which is comparable to quercetin (IC50 = 9.93 ± 0.66 µM), a known inhibitor of this enzyme. Unfortunately, all compounds showed weak activity against α-amylase (IC50 > 200 µM). Structure-based molecular modelling tools were utilised to rationalise the SAR compared to co-crystal structures with sPLA2-GX as well as α-glucosidase. This report introduces novel compounds with dual activities on biochemically unrelated enzymes mutually involved in diabetes and its complications.
  9. Fulltext Symmetric molecules with 1,4-triazole moieties as potent inhibitors of tumour-associated lactate dehydrogenase-A
    Altamimi AS, Alafeefy AM, Balode A, Vozny I, Pustenko A, El Shikh ME, et al.
    J Enzyme Inhib Med Chem, 2018 Dec;33(1):147-150.
    PMID: 29199484 DOI: 10.1080/14756366.2017.1404593
    A series of symmetric molecules incorporating aryl or pyridyl moieties as central core and 1,4-substituted triazoles as a side bridge was synthesised. The new compounds were investigated as lactate dehydro-genase (LDH, EC 1.1.1.27) inhibitors. The cancer associated LDHA isoform was inhibited with IC50 = 117-174 µM. Seven compounds exhibited better LDHA inhibition (IC50 117-136 µM) compared to known LDH inhibitor - galloflavin (IC50 157 µM).
  10. Fulltext Synthesis and evaluation of anticancer, antiphospholipases, antiproteases, and antimetabolic syndrome activities of some 3H-quinazolin-4-one derivatives
    El-Sayed NNE, Almaneai NM, Ben Bacha A, Al-Obeed O, Ahmad R, Abdulla M, et al.
    J Enzyme Inhib Med Chem, 2019 Dec;34(1):672-683.
    PMID: 30821525 DOI: 10.1080/14756366.2019.1574780
    Some new 3H-quinazolin-4-one derivatives were synthesised and screened for anticancer, antiphospholipases, antiproteases, and antimetabolic syndrome activities. Compound 15d was more potent in reducing the cell viabilities of HT-29 and SW620 cells lines to 38%, 36.7%, compared to 5-FU which demonstrated cell viabilities of 65.9 and 42.7% respectively. The IC50 values of 15d were ∼20 µg/ml. Assessment of apoptotic activity revealed that 15d decreased the cell viability by down regulating Bcl2 and BclxL. Moreover, compounds, 8j, 8d/15a/15e, 5b, and 8f displayed lowered IC50 values than oleanolic acid against proinflammatory isoforms of hGV, hG-X, NmPLA2, and AmPLA2. In addition, 8d, 8h, 8j, 15a, 15b, 15e, and 15f showed better anti-α-amylase than quercetin, whereas 8g, 8h, and 8i showed higher anti-α-glucosidase activity than allopurinol. Thus, these compounds can be considered as potential antidiabetic agents. Finally, none of the compounds showed higher antiproteases or xanthine oxidase activities than the used reference drugs.
  11. Depression Following Major Life Transitions in Women: A Review and Theory
    Moustafa AA, Crouse JJ, Herzallah MM, Salama M, Mohamed W, Misiak B, et al.
    Psychol Rep, 2020 Oct;123(5):1501-1517.
    PMID: 31470771 DOI: 10.1177/0033294119872209
    Depression can occur due to common major life transitions, such as giving birth, menopause, retirement, empty-nest transition, and midlife crisis. Although some of these transitions are perceived as positive (e.g., giving birth), they may still lead to depression. We conducted a systematic literature review of the factors underlying the occurrence of depression following major life transition in some individuals. This review shows that major common life transitions can cause depression if they are sudden, major, and lead to loss (or change) of life roles (e.g., no longer doing motherly or fatherly chores after children leave family home). Accordingly, we provide a theoretical framework that explains depression caused by transitions in women. One of the most potential therapeutic methods of ameliorating depression associated with life transitions is either helping individuals accept their new roles (e.g., accepting new role as a mother to ameliorate postpartum depression symptoms) or providing them with novel life roles (e.g., volunteering after retirement or children leave family home) may help them overcome their illness.
  12. Fulltext Modulation of NKG2D, KIR2DL and Cytokine Production by Pleurotus ostreatus Glucan Enhances Natural Killer Cell Cytotoxicity Toward Cancer Cells
    El-Deeb NM, El-Adawi HI, El-Wahab AEA, Haddad AM, El Enshasy HA, He YW, et al.
    Front Cell Dev Biol, 2019;7:165.
    PMID: 31457012 DOI: 10.3389/fcell.2019.00165
    Medicinal mushrooms have been used for centuries against cancer and infectious diseases. These positive biological effects of mushrooms are due in part to the indirect action of stimulating immune cells. The objective of the current study is to investigate the possible immunomodulatory effects of mushroom polysaccharides on NK cells against different cancer cells. In this current study, fruiting bodies isolated from cultured Pleurotus ostreatus were extracted and partially purified using DEAE ion-exchange chromatography. The activation action of the collected fractions on Natural Killer cells was quantified against three different cancer cell lines in the presence or absence of human recombinant IL2 using three different activation and co-culture conditions. The possible modes of action of mushroom polysaccharides against cancer cells were evaluated at the cellular and molecular levels. Our results indicate that P. ostreatus polysaccharides induced NK-cells cytotoxic effects against lung and breast cancer cells with the largest effect being against breast cancer cells (81.2%). NK cells activation for cytokine secretion was associated with upregulation of KIR2DL genes while the cytotoxic activation effect of NK cells against cancer cells correlated with NKG2D upregulation and induction of IFNγ and NO production. These cytotoxic effects were enhanced in the presence of IL2. Analysis of the most active partially purified fraction indicates that it is predominantly composed of glucans. These results indicate bioactive 6-linked glucans present in P. ostreatus extracts activate NK-cell cytotoxicity via regulation of activation and induction of IFNγ and NO. These studies establish a positive role for bioactive P. ostreatus polysaccharides in NK-cells activation and induction of an innate immune response against breast and lung cancer cells.
  13. Fulltext Optimization of an Extraction Solvent for Angiotensin-Converting Enzyme Inhibitors from Hibiscus sabdariffa L. Based on Its UPLC-MS/MS Metabolic Profiling
    Salem MA, Michel HE, Ezzat MI, Okba MM, El-Desoky AM, Mohamed SO, et al.
    Molecules, 2020 May 14;25(10).
    PMID: 32422967 DOI: 10.3390/molecules25102307
    Hibiscus species (Malvaceae) have been long used as an antihypertensive folk remedy. The aim of our study was to specify the optimum solvent for extraction of the angiotensin-converting enzyme inhibiting (ACEI) constituents from Hibiscus sabdariffa L. The 80% methanol extract (H2) showed the highest ACEI activity, which exceeds that of the standard captopril (IC50 0.01255 ± 0.00343 and 0.210 ± 0.005 µg/mL, respectively). Additionally, in a comprehensive metabolomics approach, an ultra-performance liquid chromatography (UPLC) coupled to the high resolution tandem mass spectrometry (HRMS) method was used to trace the metabolites from each extraction method. Interestingly, our comprehensive analysis showed that the 80% methanol extract was predominated with secondary metabolites from all classes including flavonoids, anthocyanins, phenolic and organic acids. Among the detected metabolites, phenolic acids such as ferulic and chlorogenic acids, organic acids such as citrate derivatives and flavonoids such as kaempferol have been positively correlated to the antihypertensive potential. These results indicates that these compounds may significantly contribute synergistically to the ACE inhibitory activity of the 80% methanol extract.
  14. Fulltext Preparation of Lignan-Rich Extract from the Aerial Parts of Phyllanthus niruri Using Nonconventional Methods
    Meselhy MR, Abdel-Sattar OE, El-Mekkawy S, El-Desoky AM, Mohamed SO, Mohsen SM, et al.
    Molecules, 2020 Mar 05;25(5).
    PMID: 32151037 DOI: 10.3390/molecules25051179
    Phyllanthin and related lignans were found to be responsible, at least in part, for most of the activity of Phyllanthus species. This observation encouraged the authors to develop methods for the preparation of an extract rich in phyllanthin and related lignans from the aerial parts of P. niruri L. Direct extraction with solvents produced extracts with variable yields and contents of lignans. Lignans were identified by LC-ESI-MS analysis as phyllanthin (used as marker substance), hypophyllanthin, phylltetralin, nirtetralin, and niranthin. Extraction with boiling water produced 18.10 g% (w/w) extract with a trace amount of lignans (phyllanthin content of 0.33 ± 0.10 mg/g extract), while extraction with MeOH gave 3.6 g% w/w extract with a low phyllanthin content (3.1 mg/g extract), as determined by HPLC. However, Soxhlet extraction with hexane, CH2Cl2, or acetone gave extracts with low yields (0.82, 1.12, and 3.40 g% w/w, respectively) and a higher phyllanthin contents (36.2 ± 2.6, 11.7 ± 1.68, and 11.7 ± 1.10 mg/g extract, respectively). Extraction quality and efficiency were optimized by adopting the following three different approaches: (1) Alkaline digestion of the plant material with 30% potassium hydroxide yielded 3.1 g% w/w of purified extract with high phyllanthin content (22.34 ± 0.13 mg/g); (2) microwave-assisted extraction using 80% MeOH gave an extract with a better yield (8.13 g% w/w) and phyllanthin content (21.2 ± 1.30 mg/g) (after filtration through a Diaion HP-20 column); and (3) treatment of the ground plant material at 50 °C with two hydrolytic enzymes, cellulase (9 U/g for 12 h) and then, protease (4 U/g up to 72 h) optimized the yield of extract (13.92 g% w/w) and phyllanthin content (25.9 mg/g extract and total lignans content of 85.87 mg/g extract). In conclusion, the nonconventional methods presented here are superior for optimizing the yield of extract and its lignan contents from the aerial parts of P. niruri.
  15. Fulltext Comparative Chemical Profiles of the Essential Oils from Different Varieties of Psidium guajava L
    Hassan EM, El Gendy AEG, Abd-ElGawad AM, Elshamy AI, Farag MA, Alamery SF, et al.
    Molecules, 2020 Dec 29;26(1).
    PMID: 33383905 DOI: 10.3390/molecules26010119
    Guava (Psidium guajava) leaves are commonly used in the treatment of diseases. They are considered a waste product resulting from guava cultivation. The leaves are very rich in essential oils (EOs) and volatiles. This work represents the detailed comparative chemical profiles of EOs derived from the leaves of six guava varieties cultivated in Egypt, including Red Malaysian (RM), El-Qanater (EQ), White Indian (WI), Early (E), El-Sabahya El-Gedida (ESEG), and Red Indian (RI), cultivated on the same farm in Egypt. The EOs from the leaves of guava varieties were extracted by hydro-distillation and analyzed with GC-MS. The EOs were categorized in a holistic manner using chemometric tools. The hydro-distillation of the samples yielded 0.11-0.48% of the EO (v/w). The GC-MS analysis of the extracted EOs showed the presence of 38 identified compounds from the six varieties. The sesquiterpene compounds were recorded as main compounds of E, EQ, ESEG, RI, and WI varieties, while the RM variety attained the highest content of monoterpenes (56.87%). The sesquiterpenes, β-caryophyllene (11.21-43.20%), and globulol (76.17-26.42%) were detected as the major compounds of all studied guava varieties, while trans-nerolidol (0.53-10.14) was reported as a plentiful compound in all of the varieties except for the RM variety. A high concentration of D-limonene was detected in the EOs of the RM (33.96%), WI (27.04%), and ESEG (9.10%) varieties. These major compounds were consistent with those reported for other genotypes from different countries. Overall, the EOs' composition and the chemometric analysis revealed substantial variations among the studied varieties that might be ascribed to genetic variability, considering the stability of the cultivation and climate conditions. Therefore, this chemical polymorphism of the studied varieties supports that these varieties could be considered as genotypes of P. guajava. It is worth mentioning here that the EOs, derived from leaves considered to be agricultural waste, of the studied varieties showed that they are rich in biologically active compounds, particularly β-caryophyllene, trans-nerolidol, globulol, and D-limonene. These could be considered as added value for pharmacological and industrial applications. Further study is recommended to confirm the chemical variations of the studied varieties at a molecular level, as well as their possible medicinal and industrial uses.
  16. Synthesis 4-[2-(2-mercapto-4-oxo-4H-quinazolin-3-yl)-ethyl]-benzenesulfonamides with subnanomolar carbonic anhydrase II and XII inhibitory properties
    Bozdag M, Alafeefy AM, Carta F, Ceruso M, Al-Tamimi AS, Al-Kahtani AA, et al.
    Bioorg Med Chem, 2016 09 15;24(18):4100-4107.
    PMID: 27396930 DOI: 10.1016/j.bmc.2016.06.052
    Condensation of substituted anthranilic acids with 4-isothiocyanatoethyl-benzenesulfonamide led to series of heterocyclic benzenesulfonamides incorporating 2-mercapto-quinazolin-4-one tails. These sulfonamides were investigated as inhibitors of the human carbonic anhydrase (hCA, EC 4.2.1.1) isoforms hCA I and II (cytosolic isozymes), as well as hCA XII (a transmembrane, tumor-associated enzyme also involved in glaucoma-genesis). The new sulfonamides acted as medium potency inhibitors of hCA I (KIs of 28.5-2954nM), being highly effective as hCA II (KIs in the range of 0.62-12.4nM) and XII (KIs of 0.54-7.11nM) inhibitors. All substitution patterns present in these compounds (e.g., halogens, methyl and methoxy moieties, in positions 6, 7 and/or 8 of the 2-mercapto-quinazolin-4-one ring) led to highly effective hCA II/XII inhibitors. These compounds should thus be of interest as preclinical candidates in pathologies in which the activity of these enzymes should be inhibited, such as glaucoma (CA II and XII as targets) or some tumors in which the activity of isoforms CA II and XII is dysregulated.
  17. Synthesis, Antiphospholipase A₂, Antiprotease, Antibacterial Evaluation and Molecular Docking Analysis of Certain Novel Hydrazones
    El-Sayed NN, Alafeefy AM, Bakht MA, Masand VH, Aldalbahi A, Chen N, et al.
    Molecules, 2016 Dec 02;21(12).
    PMID: 27918459
    Some novel hydrazone derivatives 6a-o were synthesized from the key intermediate 4-Chloro-N-(2-hydrazinocarbonyl-phenyl)-benzamide 5 and characterized using IR, ¹H-NMR, 13C-NMR, mass spectroscopy and elemental analysis. The inhibitory potential against two secretory phospholipase A₂ (sPLA₂), three protease enzymes and eleven bacterial strains were evaluated. The results revealed that all compounds showed preferential inhibition towards hGIIA isoform of sPLA₂ rather than DrG-IB with compounds 6l and 6e being the most active. The tested compounds exhibited excellent antiprotease activity against proteinase K and protease from Bacillus sp. with compound 6l being the most active against both enzymes. Furthermore, the maximum zones of inhibition against bacterial growth were exhibited by compounds; 6a, 6m, and 6o against P. aeruginosa; 6a, 6b, 6d, 6f, 6l, 6m, 6n, and 6o against Serratia; 6k against S. mutans; and compounds 6a, 6d, 6e, 6m, and 6n against E. feacalis. The docking simulations of hydrazones 6a-o with GIIA sPLA₂, proteinase K and hydrazones 6a-e with glutamine-fructose-6-phosphate transaminase were performed to obtain information regarding the mechanism of action.
  18. Neurotoxin-Induced Rodent Models of Parkinson's Disease: Benefits and Drawbacks
    El-Gamal M, Salama M, Collins-Praino LE, Baetu I, Fathalla AM, Soliman AM, et al.
    Neurotox Res, 2021 Jun;39(3):897-923.
    PMID: 33765237 DOI: 10.1007/s12640-021-00356-8
    Parkinson's disease (PD), the second most common neurodegenerative disorder, is characterized by cardinal motor impairments, including akinesia and tremor, as well as by a host of non-motor symptoms, including both autonomic and cognitive dysfunction. PD is associated with a death of nigral dopaminergic neurons, as well as the pathological spread of Lewy bodies, consisting predominantly of the misfolded protein alpha-synuclein. To date, only symptomatic treatments, such as levodopa, are available, and trials aiming to cure the disease, or at least halt its progression, have not been successful. Wong et al. (2019) suggested that the lack of effective therapy against neurodegeneration in PD might be attributed to the fact that the molecular mechanisms standing behind the dopaminergic neuronal vulnerability are still a major scientific challenge. Understanding these molecular mechanisms is critical for developing effective therapy. Thirty-five years ago, Calne and William Langston (1983) raised the question of whether biological or environmental factors precipitate the development of PD. In spite of great advances in technology and medicine, this question still lacks a clear answer. Only 5-15% of PD cases are attributed to a genetic mutation, with the majority of cases classified as idiopathic, which could be linked to exposure to environmental contaminants. Rodent models play a crucial role in understanding the risk factors and pathogenesis of PD. Additionally, well-validated rodent models are critical for driving the preclinical development of clinically translatable treatment options. In this review, we discuss the mechanisms, similarities and differences, as well as advantages and limitations of different neurotoxin-induced rat models of PD. In the second part of this review, we will discuss the potential future of neurotoxin-induced models of PD. Finally, we will briefly demonstrate the crucial role of gene-environment interactions in PD and discuss fusion or dual PD models. We argue that these models have the potential to significantly further our understanding of PD.
  19. Fulltext Enhancement of Ceramics Based Red-Clay by Bulk and Nano Metal Oxides for Photon Shielding Features
    Elsafi M, Dib MF, Mustafa HE, Sayyed MI, Khandaker MU, Alsubaie A, et al.
    Materials (Basel), 2021 Dec 19;14(24).
    PMID: 34947471 DOI: 10.3390/ma14247878
    We prepared red clays by introducing different percentages of PbO, Bi2O3, and CdO. In order to understand how the introduction of these oxides into red clay influences its attenuation ability, the mass attenuation coefficient of the clays was experimentally measured in a lab using an HPGe detector. The theoretical shielding capability of the material present was obtained using XCOM to verify the accuracy of the experimental results. We found that the experimental and theoretical values agree to a very high degree of precision. The effective atomic number (Zeff) of pure red clay, and red clay with the three metal oxides was determined. The pure red clay had the lowest Zeff of the tested samples, which means that introducing any of these three oxides into the clay will greatly enhance its Zeff, and consequently its attenuation capability. Additionally, the Zeff for red clay with 10 wt% CdO is lower than the Zeff of red clay with 10 wt% Bi2O3 and PbO. We also prepared red clay using 10 wt% CdO nanoparticles and compared its attenuation ability with the red clay prepared with 10 wt% PbO, Bi2O3, and CdO microparticles. We found that the MAC of the red clay with 10 wt% nano-CdO was higher than the MAC of the clay with microparticle samples. Accordingly, nanoparticles could be a useful way to enhance the shielding ability of current radiation shielding materials.
  20. Fulltext Heat and mass transfer analysis of assisting and opposing radiative flow conveying ternary hybrid nanofluid over an exponentially stretching surface
    Nagaraja KV, Khan U, Madhukesh JK, Hassan AM, Prasannakumara BC, Ben Kahla N, et al.
    Sci Rep, 2023 Sep 08;13(1):14795.
    PMID: 37684341 DOI: 10.1038/s41598-023-41916-6
    Access to dependable and environmentally friendly energy sources is critical to a country's economic growth and long-term development. As countries seek greener energy alternatives, the interaction of environmental elements, temperature, and sunlight becomes more critical in utilizing renewable energy sources such as wind and bioenergy. Solar power has received much attention due to extraordinary efficiency advances. under this context, the present work focus on solar radiation and chemical processes in the presence of modified ternary hybrid nanofluids (THNFs) circulating over an exponentially stretched surface in both aiding flow (A-F) and opposing flow (O-F) circumstances. The primary objective of this investigation is to dive into the complicated dynamics of these structures, which are distinguished by complex interactions involving radiation, chemical reactions, and the movement of fluids. We construct reduced ordinary differential equations from the governing equations using suitable similarity transformations, which allows for a more in-depth examination of the liquid's behavior. Numerical simulations using the Runge-Kutta Fehlberg (RKF) approach and shooting techniques are used to understand the underlying difficulties of these reduced equations. The results show that thermal radiation improves heat transmission substantially under O-F circumstances in contrast to A-F conditions. Furthermore, the reaction rate parameter has an exciting connection with concentration levels, with greater rates corresponding to lower concentrations. Furthermore, compared to the O-F scenario, the A-F scenario promotes higher heat transfer in the context of a modified nanofluid. Rising reaction rate and solid fraction volume enhanced mass transfer rate. The rate of thermal distribution in THNFs improves from 0.13 to 20.4% in A-F and 0.16 to 15.06% in O-F case when compared to HNFs. This study has real-world implications in several fields, including developing more efficient solar water heaters, solar thermal generating plants, and energy-saving air conditioners.
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