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The last few decades have seen an overwhelming increase in the amount of research carried out on the use of inorganic nanoparticles. More fascinating is the tremendous progress made in the use of chalcogen and chalcogenide nanoparticles in cancer theranostics. These nanomaterials, which were initially synthesized through chemical methods, have now been efficiently produced using different plant materials. The paradigm shift towards the biogenic route of nanoparticle synthesis stems from its superior advantages of biosafety, eco-friendliness, and simplicity, among others. Despite a large number of reviews available on inorganic nanoparticle synthesis through green chemistry, there is currently a dearth of information on the green synthesis of chalcogens and chalcogenides for cancer research. Nanoformulations involving chalcogens such as sulfur, selenium, and tellurium and their respective chalcogenides have recently emerged as promising tools in cancer therapeutics and diagnosis. Similar to other inorganic nanoparticles, chalcogens and chalcogenides have been synthesized using plant extracts and their purified biomolecules. In this review, we provide an up-to-date discussion of the recent progress that has been made in the plant-mediated synthesis of chalcogens and chalcogenides with a special focus on their application in cancer theranostics. [ABSTRACT FROM AUTHOR]

The present study investigates the cytotoxic effect of the chemical fractions of Allium cepa (yellow variety) on Human Embryonic Kidney (HEK293) cells. Allium cepa was blended into paste and macerated in distilled water before subjecting to liquid–liquid fractionation, yielding the dichloromethane, ethyl acetate (EtOAc), butanol, and aqueous fractions. Their cytotoxicity on HEK293 cells were evaluated via MTT assay. The cytotoxic fraction (EtOAc) was further evaluated for its oxidative, pro‐inflammatory, and apoptotic effects on the cells. The incubation of cells with EtOAc led to depleted level of GSH, SOD, and catalase activities, and elevated levels of malondialdehyde, nitric oxide, and myeloperoxidase as well as apoptotic activities. GC‐MS analysis of EtOAc revealed allyl ionone, pentadecanoic acid, and phytol acetate as the predominant fatty acids, while ergost‐7‐en‐3β‐ol, campesterol, cycloartenol‐3β acetate, sitosterol, and fucosterol as the predominant sterols. These results portray the cytotoxic effect of the EtOAc fraction of A. cepa on HEK293 cells. Practical applications: There have been increasing concerns in the toxicity and safety of foods. Allium cepa (onions) is among the common globally grown and consumed plant food. This study investigated its cytotoxic effect on normal Human Embryonic Kidney (HEK293) Cells. Although only the ethyl acetate fraction was cytotoxic against the cell line, it, however, portrays a need for caution in its usage. [ABSTRACT FROM AUTHOR]

Chloro, fluoro, and nitro derivatives of 7‐amino‐5‐aryl‐6‐cyano‐5H‐pyrano pyrimidin‐2,4‐diones were produced by reacting malononitrile, barbituric acid, and aromatic aldehydes together with a DABCO catalyst in an aqueous one‐pot reaction. This is the first report of these compounds being synthesized with DABCO as a catalyst, which produced the compounds in yields in excess of 90%. The 2,4‐difluoro derivative (11) was novel. The structures of the synthesized compounds were elucidated by means of 1H, 13C, and 2D NMR spectroscopy. Compound 2 (2‐Cl derivative) had MBC values of <200μM against both Staphylococcus aureus and MRSA, and the 2‐nitro derivative 5 had an MBC of 191μM against the Gram–ve Escherichia coli. The synthesized compounds were also tested for their anticancer activity against a HeLa cell line, where all the compounds showed better activity (IC50 values between 129μM and 340μM) than 5‐fluorouracil, a commonly known anticancer drug. [ABSTRACT FROM AUTHOR]

New complexes [(ŋ6-p-cymene)Ru(C5H4N-2-CH=N-Ar)X]PF6 [ X = Br (1), I (2); Ar = 4-fluorophenyl (a), 4-chlorophenyl (b), 4-bromophenyl (c), 4-iodophenyl (d), 2,5-dichlorophenyl (e)] were prepared, as well as 3a-3e (X = Cl) and the new complexes [(ŋ6-arene) RuCl(N-N)]PF6 (arene = C6H5OCH2CH2OH, N-N = 2,2'-bipyridine (4), 2,6-(dimethylphenyl)-pyridin-2-yl-methylene amine (5), 2,6- (diisopropylphenyl)- pyridin-2-yl-methylene amine (6); arene = p-cymene, N-N = 4-(aminophenyl)-pyridin-2-yl-methylene amine (7)]. X-ray diffraction studies were performed for 1a, 1b, 1c, 1d, 2b, 5 and 7. Cytotoxicities of 1a-1d and 2 were established versus human cancer cells epithelial colorectal adenocarcinoma (Caco-2) (IC50: 35.8-631.0 μM), breast adenocarcinoma (MCF7) (IC50: 36.3-128.8.0 μM) and hepato cellular carcinoma (HepG2) (IC50: 60.6-439.8 μM), 3a-3e were tested against HepG2 and Caco-2 and 4-7 were tested against Caco-2. 1-7 were tested against non-cancerous human epithelial kidney cells. 1 and 2 were more selective towards tumor cells than the anticancer drug 5- fluorouracil (5-FU), but 3a-3e (X = Cl) were not selective. 1 and 2 had good activity against MCF7, some with lower IC50 than 5-FU. Complexes with X = Br or I had moderate activity against Caco-2 and HepG2, but those with Cl were inactive. Antibacterial activities of 1a, 2b, 3a and 7 were tested against antibacterial susceptible and resistant Gram-negative and positive bacteria. 1a, 2b and 3a showed activity against methicillin-resistant S. aureus (MIC = 31-2000 μg.mL-1). [ABSTRACT FROM AUTHOR]

The large numbers of hepatic disorders of a genetic origin continues to drive the quest for safe and efficient non-viral gene delivery systems with the design features suitable for in vivo application. Here, we examine the efficacy of hepatocyte-specific stealth lipoplexes in the human hepatoma cell line HepG2. Thus cationic liposomes were formulated with the cytofectin N, N-dimethylaminopropylaminylsuccinylcholesterylformylhydrazide (MS09), the neutral co-lipid 1,2-dioleoyl- sn-glycero-3-phosphoethanolamine (DOPE) with and without the asialoglycoprotein receptor (ASGP-R)-specific ligand cholesteryl-β- d-galactopyranoside (Chol-β-Gal), and 1,2-distearoyl- sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol) 2000] (DSPE-PEG2000) in the 0-5 mol% range. Lipoplexes formed with pCMV-luc plasmid DNA were characterized by cryo-transmission electron microscopy (cryo-TEM), gel retardation, and ethidium displacement assays showed that cargo DNA was compacted and protected from serum nucleases by cationic liposomes. Hydrodynamic diameters were in the 114 ± 6.2-224 ± 5.3 nm size range while particle sizes, polydispersity indices (PDI), and ζ-potentials decreased with increasing degree of PEGylation. Cell viabilities of >75% were attained by targeted complexes in the ASGP-R-negative human embryonal kidney cell line HEK293 and in ASGP-R-positive HepG2 cells. Targeted 5% PEGylated lipoplexes at N/P ratio = 3.5 achieved the highest transfection activity in the hepatocyte-derived cells while competition assays and fluorescence microscopy confirmed that all targeted lipoplexes transfected HepG2 cells largely by ASGP-R mediation. Practical applications: The findings of this study show that stealth lipoplexes bearing PEG2000 at a density of 5 mol% may be effectively targeted to the ASGP-R, which is almost exclusively expressed on hepatocytes and hepatocyte-derived cells, by inclusion of the simple monoantennary cholesteryl-β- d-galactopyranoside at 10 mol% in the parent cationic liposome preparation. The remarkable efficacy of this cholesteryl glycoside ligand, in the presence of serum, shows that a β-glycosidic link between the cholesteryl membrane anchor moiety and the pyranose ring is sufficient to ensure efficient ASGP-R recognition of the sugar hexose at clinically relevant PEG grafting densities, by lipoplexes into which it has been incorporated. We conclude that the targeted, PEGylated lipoplexes characterized and evaluated in this study constitute a solid platform for the development of hepatotropic nucleic acid delivery vehicles. This study shows that stealth lipoplexes bearing PEG2000 at a density of 5 mol% may be effectively targeted to the asialoglycoprotein receptor (ASGP-R), which is almost exclusively expressed on hepatocytes and hepatocyte-derived cells, by inclusion of the simple monoantennary cholesteryl-β- d-galactopyranoside at 10 mol% in the parent cationic liposome preparation. The remarkable efficacy of this cholesteryl glycoside ligand, in the presence of serum, shows that a β-glycosidic link between the cholesteryl membrane anchor and the pyranose ring is sufficient to ensure efficient ASGP-R recognition of the sugar hexose at clinically relevant PEG grafting densities. Targeted, PEGylated lipoplexes characterized and evaluated here, constitute a solid platform for the development of hepatotropic nucleic acid delivery vehicles. [ABSTRACT FROM AUTHOR]

A new series of 5-fluoro- N4-(3-(4-substitutedbenzylamino)phenyl)- N2-(4-morpholinophenyl)pyrimidine-2,4-diamine derivatives ( 7a, 7b, 7c, 7d, 7e, 7f, 7g, 7h, 7i, 7j) are prepared from using an compound 5-fluoro- N4-(3-(aminophenyl)- N2-(4-morpholinophenyl)pyrimidine-2,4-diamine ( 5). The structures of the newly synthesized products are established from their spectral 1H-NMR, 13C-NMR, 19F-NMR, ESI-MS, and analytical data. Here we report the synthesized compounds and larvicidal activity. All the compounds are screened for their significant larvicidal activity against third instar larvae at 24, 48, and 78-h time exposure, and values were compared with standard drug Malathion. The Compounds 7i, 7a, 7c, 7f, and 7j exhibited significant activity. However the compounds 7b, 7e, 7d, and 7h showed excellent activity when compared to the above compounds and to standard drug malathion too because of the presence of mild electron withdrawing groups such as trifluoro, fluorine, hydroxy, nitro, and methoxy derivatives which are attached to the benzyl ring. [ABSTRACT FROM AUTHOR]

Layered double hydroxides (LDHs) exhibit characteristic anion-exchange chemistry making them ideal carriers of negatively charged molecules like deoxyribonucleic acid (DNA). In this study, hydrotalcite (Mg−Al) and hydrotalcite-like compounds (Mg−Fe, Zn−Al, and Zn−Fe), also known as LDHs, were evaluated for their potential application as a carrier of DNA. LDHs were prepared by coprecipitation at low supersaturation and characterized by Powder X-ray diffraction (XRD), infrared (IR), Raman, and inductively coupled plasma-optical emission spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). XRD patterns showed strong and sharp diffraction peaks for the (003) and (006) planes indicating well-ordered crystalline materials. TEM images yielded irregular circular to hexagonal-shaped particles of 50-250 nm in size. Varying degrees of DNA binding was observed for all the compounds, and nuclease digestion studies revealed that the LDHs afford some degree of protection to the bound DNA. Minimal toxicity was observed in human embryonic kidney (HEK293), cervical cancer (HeLa) and hepatocellular carcinoma (HepG2) cell lines with most showing a cell viability in excess of 80 %. All LDH complexes promoted significant levels of luciferase gene expression, with the DNA:Mg−Al LDHs proving to be the most efficient in all cell lines. [ABSTRACT FROM AUTHOR]

It is important to consider viruses in water quality because of their incidence as causal agents for diarrhoeal disease, and due to their characteristics, which allow them to survive in changing environmental conditions indefinitely. This study assessed the viral quality of the Umgeni River in South Africa seasonally. A two-step tangential flow filtration process was setup to remove the bacteria and to concentrate the virus populations from large volume water samples. The concentrated water samples contained up to 659 and 550 pfu/mL of somatic and F-RNA coliphages, respectively. Several virus families including Adenoviridae, Herpesviridae, Orthomyxoviridae, Picornaviridae, Poxviridae and Reoviridae were found in the river based on the morphologies examined under transmission electron microscopy. All concentrated water samples produced substantial cytopathic effects on the Vero, HEK 293, Hela and A549 cell lines. These results indicate the potential of viruses in the water samples especially from the lower catchment areas of the Umgeni River to infect human hosts throughout the year. The present study highlights the importance of routine environmental surveillance of human enteric viruses in water sources. This can contribute to a better understanding of the actual burden of disease on those who might be using the water directly without treatment. [ABSTRACT FROM AUTHOR]

Liposomes form a major class of non-viral vectors for short interfering RNA delivery, however tissue and cell-specific targeting are additional requirements in the design of short interfering RNA delivery systems with a therapeutic potential. Selective delivery of liposomes to hepatocytes may be achieved by directing complexes to the asialoglycoprotein receptor, which is expressed on hepatocytes, and which displays high affinity for the β- d-galactopyranosyl moiety. We aimed to show that the d-galactopyranosyl ring in direct β-glycosidic link to cholesterol, when formulated into liposomes with 3β[ N-( N′, N′-dimethylaminopropane) carbamoyl] cholesterol (Chol-T) or its quaternary trimethylammonium analogue (Chol-Q), may promote targeted delivery of cytotoxic short interfering RNA to the human hepatoma cell line HepG2 via the asialoglycoprotein receptor. Liposome-short interfering RNA interactions were characterized by electron microscopy, dye displacement, gel retardation and nuclease assays. Stable short interfering RNA-protective lipoplexes were formed at N/P ratios in the range 5:1-7:1. Targeted lipoplex 4 achieved high transfection efficiencies at 50 n m short interfering RNA (70%) and <10% in a competition assay, whilst untargeted complexes reached low levels at the same concentration (<25%). Transfection efficiencies of all lipoplexes in the asialoglycoprotein receptor-negative cell line HEK293 under the same conditions were low. Lipoplexes containing cholesteryl-β- d-galactopyranoside may therefore form the basis for the development of useful hepatotropic short interfering RNA delivery vectors. [ABSTRACT FROM AUTHOR]

New complexes [(ŋ6-p-cymene)Ru(C5H4N-2-CH=N-Ar)X]PF6 [ X = Br (1), I (2); Ar = 4-fluorophenyl (a), 4-chlorophenyl (b), 4-bromophenyl (c), 4-iodophenyl (d), 2,5-dichlorophenyl (e)] were prepared, as well as 3a-3e (X = Cl) and the new complexes [(ŋ6-arene) RuCl(N-N)]PF6 (arene = C6H5OCH2CH2OH, N-N = 2,2'-bipyridine (4), 2,6-(dimethylphenyl)-pyridin-2-yl-methylene amine (5), 2,6- (diisopropylphenyl)- pyridin-2-yl-methylene amine (6); arene = p-cymene, N-N = 4-(aminophenyl)-pyridin-2-yl-methylene amine (7)]. X-ray diffraction studies were performed for 1a, 1b, 1c, 1d, 2b, 5 and 7. Cytotoxicities of 1a-1d and 2 were established versus human cancer cells epithelial colorectal adenocarcinoma (Caco-2) (IC50: 35.8-631.0 μM), breast adenocarcinoma (MCF7) (IC50: 36.3-128.8.0 μM) and hepato cellular carcinoma (HepG2) (IC50: 60.6-439.8 μM), 3a-3e were tested against HepG2 and Caco-2 and 4-7 were tested against Caco-2. 1-7 were tested against non-cancerous human epithelial kidney cells. 1 and 2 were more selective towards tumor cells than the anticancer drug 5- fluorouracil (5-FU), but 3a-3e (X = Cl) were not selective. 1 and 2 had good activity against MCF7, some with lower IC50 than 5-FU. Complexes with X = Br or I had moderate activity against Caco-2 and HepG2, but those with Cl were inactive. Antibacterial activities of 1a, 2b, 3a and 7 were tested against antibacterial susceptible and resistant Gram-negative and positive bacteria. 1a, 2b and 3a showed activity against methicillin-resistant S. aureus (MIC = 31-2000 μg.mL-1). [ABSTRACT FROM AUTHOR]