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571.
Watkins NN Sridhar S Cheng X Chen GD Toner M Rodriguez W Bashir R 《Lab on a chip》2011,11(8):1437-1447
We have developed a microfabricated biochip that enumerates CD4+ T lymphocytes from leukocyte populations obtained from human blood samples using electrical impedance sensing and immunoaffinity chromatography. T cell counts are found by obtaining the difference between the number of leukocytes before and after depleting CD4+ T cells with immobilized antibodies in a capture chamber. This differential counting technique has been validated to analyze physiological concentrations of leukocytes with an accuracy of ~9 cells per μL by passivating the capture chamber with bovine serum albumin. In addition, the counter provided T cell counts which correlated closely with an optical control (R(2) = 0.997) for CD4 cell concentrations ranging from approximately 100 to 700 cells per μL. We believe that this approach can be a promising method for bringing quantitative HIV/AIDS diagnostics to resource-poor regions in the world. 相似文献
572.
Umer Farooq Sébastien Simon Medad T. Tweheyo Johan Sjöblom 《Journal of Dispersion Science and Technology》2013,34(5):701-708
Dynamic and equilibrium interfacial tensions between crude oil fractions and aqueous solutions of various compositions and pH were measured. The basic oil components seemed to determine the interfacial tensions at pH 2, while the non-dissociated and dissociated acidic components governed the interfacial tension at the natural pH and pH 9, respectively. The ionic composition of the aqueous phase influenced the degree of dissociation of the acidic components at pH 9: Na+ ions in the aqueous phase promoted dissociation of the interfacial acidic components (compared to pure water), while Ca2+ ions resulted in complexation with the dissociated acids and most likely formation of stable interfacial films. The amount of Ca2+ determined which of these phenomena that dominated when both ions were present in sea water solutions. Generally, the interfacial tensions of the oil fractions were lower when measured against the high salinity aqueous solutions than against the corresponding low salinity solutions. 相似文献
573.
Chamakura K Perez-Ballestero R Luo Z Bashir S Liu J 《Colloids and surfaces. B, Biointerfaces》2011,84(1):88-96
Engineered nanomaterials display significant advantages due to their unique nanostructure, along with their tuneable properties for the designed application. Silver nanoparticles (Ag-NPs) have drawn attention due to their use as potent bactericidal agents and were characterized in this research to provide an understanding of the interaction between nanomaterials and bacteria. This work presents the bactericidal performance of Ag-NPs using Escherichia coli (E. coli) as a model microorganism. Several state-of-the-art techniques, such as high-angle annular dark-field detector in scanning transmission electron microscopy, and energy filtered imaging in electron energy loss spectroscopy, were employed to obtain nanostructural and elemental information. The bactericidal activities of Ag-NPs were then compared with two commonly used disinfectants, sodium hypochlorite (NaClO) and phenol (C(6)H(5)OH). These two chemical disinfectants exhibited rapid bactericidal activity, showing a minimal bactericidal concentration (MBC) of 16 parts-per-million (ppm) and 16 part-per-thousand (ppth), respectively for NaClO and C(6)H(5)OH within about 10 min. In contrast, Ag-NPs exhibit slow but long-term bactericidal effect demonstrating MBCs of 0.6 parts-per-million (ppm) within 6h when used as disinfectant. An advantage using Ag-NPs to inactivate E coli at low dosages is negligible environmental waste or hazardous by-products. The results showed that Ag-NPs caused bacterial inactivation by a mechanism involving several steps, including cell wall and cytoplasmic membrane damage. 相似文献
574.
In this investigation we analyze the rotating three-dimensional magnetohydrodynamic flow of Maxwell fluid in attendance of binary chemical reaction with activation energy. Furthermore, effects of non-Fourier heat flux are taken into account. Formulation is done in the presence of heat and mass convective boundary conditions. Self-similar forms from boundary layer equations are obtained using apposite transformations. Numerical solution is obtained via built-in bvp-4c function in MATLAB for the system of differential equations. Effects of ensuing parameters on flow distributions are portrayed graphically. It is witnessed that increasing values of rotational parameter lowers the velocity profile and both Biot numbers have escalating effect on temperature and concentration distributions. A comparative study to a previously done investigation is also included to corroborate our results. 相似文献
575.
Mohammad Sameer Zubair Muhammad Farooq Hussain Munis Ibtisam M. Alsudays Khalid H. Alamer Urooj Haroon Asif Kamal Musrat Ali Junaid Ahmed Zimen Ahmad Houneida Attia 《Molecules (Basel, Switzerland)》2022,27(14)
Cherry is a fleshy drupe, and it is grown in temperate regions of the world. It is perishable, and several biotic and abiotic factors affect its yield. During April–May 2021, a severe fruit rot of cherry was observed in Swat and adjacent areas. Diseased fruit samples were collected, and the disease-causing pathogen was isolated on PDA. Subsequent morphological, microscopic, and molecular analyses identified the isolated pathogen as Aspergillus flavus. For the control of the fruit rot disease of cherry, iron oxide nanoparticles (Fe2O3 NPs) were synthesized in the leaf extract of Calotropis procera and characterized. Fourier transform infrared (FTIR) spectroscopy of synthesized Fe2O3 NPs showed the presence of capping and stabilizing agents such as alcohols, aldehydes, and halo compounds. X-ray diffraction (XRD) analysis verified the form and size (32 nm) of Fe2O3 NPs. Scanning electron microscopy (SEM) revealed the spinal-shaped morphology of synthesized Fe2O3 NPs while X-ray diffraction (EDX) analysis displayed the occurrence of main elements in the samples. After successful preparation and characterization of NPs, their antifungal activity against A. flavus was determined by poison technique. Based on in vitro and in vivo antifungal activity analyses, it was observed that 1.0 mg/mL concentration of Fe2O3 can effectively inhibit the growth of fungal mycelia and decrease the incidence of fruit rot of cherry. The results confirmed ecofriendly fungicidal role of Fe2O3 and suggested that their large-scale application in the field to replace toxic chemical fungicides. 相似文献
576.
Zakariyya Uba Zango John Ojur Dennis A. I. Aljameel Fahad Usman Mohammed Khalil Mohammed Ali Bashir Abubakar Abdulkadir Saja Algessair Osamah A. Aldaghri Khalid Hassan Ibnaouf 《Molecules (Basel, Switzerland)》2022,27(15)
Successful synthesis of ZnO-chitosan nanocomposites was conducted for the removal of methylene blue from an aqueous medium. Remarkable performance of the nanocomposites was demonstrated for the effective uptake of the dye, thereby achieving 83.77, 93.78 and 97.93 mg g−1 for the chitosan, 5 wt.% ZnO-Chitosan and 10 wt.% ZnO-Chitosan, respectively. The corresponding adsorption efficiency was 88.77, 93.78 and 97.95 for the chitosan, 5 wt.% ZnO-Chitosan and 10 wt.% ZnO-Chitosan, respectively. Upon regeneration, good reusability of the nanocomposites was manifested for the continuous removal of the dye up to six consecutive cycles. The adsorption process was kinetically described by a pseudo-first order model, while the isotherms were best fitted by the Langmuir model. 相似文献
577.
Mudassir Farooq Faisal Usman Sumera Zaib Hamid Saeed Shah Qazi Adnan Jamil Fatima Akbar Sheikh Ajmal Khan Sameh Rabea Soheir A. A. Hagras Gaber El-Saber Batiha Imtiaz Khan 《Molecules (Basel, Switzerland)》2022,27(10)
Voriconazole (VRC) is a broad-spectrum antifungal agent belonging to BCS class II (biopharmaceutical classification system). Despite many efforts to enhance its solubility, this primary issue still remains challenging for formulation scientists. Transethosomes (TELs) are one of the potential innovative nano-carriers for improving the solubility and permeation of poorly soluble and permeable drugs. We herein report voriconazole-loaded transethosomes (VRCT) fabricated by the cold method and followed by their incorporation into carbopol 940 as a gel. The prepared VRCT were evaluated for % yield, % entrapment efficiency (EE), surface morphology, possible chemical interaction, particle size, zeta potential, and polydispersity index (PDI). The optimized formulation had a particle size of 228.2 nm, a zeta potential of −26.5 mV, and a PDI of 0.45 with enhanced % EE. Rheology, spreadability, extrudability, in vitro release, skin permeation, molecular docking, antifungal, and antileishmanial activity were also assessed for VRCT and VRC loaded transethosomal gel (VTEG). Ex-vivo permeation using rat skin depicted a transdermal flux of 22.8 µg/cm2/h with enhanced efficiency up to 4-fold. A two-fold reduction in inhibitory as well as fungicidal concentration was observed against various fungal strains by VRCT and VTEG besides similar results against L-donovani. The development of transethosomal formulation can serve as an efficient drug delivery system through a topical route with enhanced efficacy and better patient compliance. 相似文献
578.
Syaifullah Muhammad Abdul Khalil H. P. S. Shazlina Abd Hamid Mohammed Danish M. Marwan Yunardi Yunardi C. K. Abdullah M. Faisal Esam Bashir Yahya 《Molecules (Basel, Switzerland)》2022,27(18)
Patchouli extracts and oils extracted from Pogostemon cablin are essential raw material for the perfume and cosmetics industries, in addition to being used as a natural additive for food flavoring. Steam distillation is a standard method used for plant extraction. However, this method causes thermal degradation of some essential components of the oil. In this study, patchouli was extracted with supercritical carbon dioxide (SC-CO2) under different conditions of pressure (10–30 MPa) and temperature (40–80 °C). The chemical components of the crude extracted oil and the functional group were characterized using gas chromatography-mass spectrometry (GC-MS) and Fourier Transform Infrared Spectroscopy (FT-IR). The extraction with supercritical carbon dioxide was shown to provide a higher yield (12.41%) at a pressure of 20 MPa and a temperature of 80 °C. Patchouli alcohol, Azulene, δ-Guaiene, and Seychellene are the main bioactive compounds that GC-MS results have identified. FTIR spectra showed alcohol, aldehyde, and aromatic ring bond stretching peaks. Extraction of patchouli with supercritical carbon dioxide provided a higher yield and a better quality of the crude patchouli oil. 相似文献
579.
Khansa Jamil Sahir Hameed Khattak Anum Farrukh Sania Begum Muhammad Naeem Riaz Aish Muhammad Tahira Kamal Touqeer Taj Imran Khan Sundus Riaz Huma Batool Kaleemullah Mandokhail Sabahat Majeed Sajid Ali Khan Bangash Alia Mushtaq Shahab Bashir Imdad Kaleem Fahed Pervaiz Aamir Rasool Muhammad Ammar Amanat Ghulam Muhammad Ali 《Molecules (Basel, Switzerland)》2022,27(19)
Background: Type 2 diabetes mellitus (DM2) is a chronic and sometimes fatal condition which affects people all over the world. Nanotherapeutics have shown tremendous potential to combat chronic diseases—including DM2—as they enhance the overall impact of drugs on biological systems. Greenly synthesized silver nanoparticles (AgNPs) from Catharanthus roseus methanolic extract (C. AgNPs) were examined primarily for their cytotoxic and antidiabetic effects. Methods: Characterization of C. AgNPs was performed by UV–vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and atomic force microscopy (AFM). The C. AgNPs were trialed on Vero cell line and afterwards on an animal model (rats). Results: The C. AgNPs showed standard structural and functional characterization as revealed by FTIR and XRD analyses. The zetapotential analysis indicated stability while EDX analysis confirmed the formation of composite capping with Ag metal. The cytotoxic effect (IC50) of C. AgNPs on Vero cell lines was found to be 568 g/mL. The animal model analyses further revealed a significant difference in water intake, food intake, body weight, urine volume, and urine sugar of tested rats after treatment with aqueous extract of C. AgNPs. Moreover, five groups of rats including control and diabetic groups (NC1, PC2, DG1, DG2, and DG3) were investigated for their blood glucose and glycemic control analysis. Conclusions: The C. AgNPs exhibited positive potential on the Vero cell line as well as on experimental rats. The lipid profile in all the diabetic groups (DG1-3) were significantly increased compared with both of the control groups (p < 0.05). The present study revealed the significance of C. AgNPs in nanotherapeutics. 相似文献
580.
Syed Luqman Shah Kashif Bashir Hafiz Majid Rasheed Jamil Ur Rahman Muhammad Ikram Abdul Jabbar Shah Kamlah Ali Majrashi Sulaiman Mohammed Alnasser Farid Menaa Taous Khan 《Molecules (Basel, Switzerland)》2022,27(24)
This study aimed to establish the phytochemical profile of Glochidion velutinum and its cytotoxic activity against prostate cancer (PC-3) and breast cancer (MCF-7) cell lines. The phytochemical composition of G. velutinum leaf extract and its fractions was established with the help of total phenolic and flavonoid contents and LC-MS/MS-based metabolomics analysis. The crude methanolic extract and its fractions were studied for pharmacological activity against PC-3 and MCF-7 cell lines using the MTT assay. The total phenolic content of the crude extract and its fractions ranged from 44 to 859 µg GAE/mg of sample whereas total flavonoid contents ranged from 20 to 315 µg QE/mg of sample. A total of forty-eight compounds were tentatively dereplicated in the extract and its fractions. These phytochemicals included benzoic acid derivatives, flavans, flavones, O-methylated flavonoids, flavonoid O- and C-glycosides, pyranocoumarins, hydrolysable tannins, carbohydrate conjugates, fatty acids, coumarin glycosides, monoterpenoids, diterpenoids, and terpene glycosides. The crude extract (IC50 = 89 µg/mL), the chloroform fraction (IC50 = 27 µg/mL), and the water fraction (IC50 = 36 µg/mL) were found to be active against the PC-3 cell line. However, the crude extract (IC50 = 431 µg/mL), the chloroform fraction (IC50 = 222 µg/mL), and the ethyl acetate fraction (IC50 = 226 µg/mL) have shown prominent activity against breast cancer cells. Moreover, G. velutinum extract and its fractions presented negligible toxicity to normal macrophages at the maximum tested dose (600 µg/mL). Among the compounds identified through LC-MS/MS-based metabolomics analysis, epigallocatechin gallate, ellagic acid, isovitexin, and rutin were reported to have anticancer activity against both prostate and breast cancer cell lines and might be responsible for the cytotoxic activities of G. velutinum extract and its bioactive fractions. 相似文献