Simultaneous determination of metolazone and losartan potassium in their binary mixtures using high‐performance liquid chromatography with fluorimetric detection: application to combined tablets and spiked human plasma

A new, specific and sensitive reversed‐phase high‐performance liquid chromatography method was developed for the simultaneous determination of metolazone (MET) and losartan potassium (LOS). Good chromatographic separation was achieved within 6.0 min on a 150 × 4.6 mm i.d., 5 µm Waters, Ireland and ProDIGY 5 ODS 3 100 A column. A mobile phase containing a mixture of methanol and 0.02 M phosphate buffer (65:35, v/v) at pH 3.0 was used. The analysis was performed at a flow rate of 1 mL/min with fluorescence detection at 410 nm after excitation at 230 nm. Aspirin (ASP) was used as an internal standard. The proposed method was rectilinear over 2.0–40.0 (MET) and 40.0–800.0 ng/mL (LOS), with limits of detection of 0.22 and 4.52 ng/mL and limits of quantification of 0.68 and 13.70 ng/mL for MET and LOS, respectively. The method was successfully applied for the simultaneous analysis of the studied drugs in their laboratory‐prepared mixtures, single tablets and co‐formulated tablets. Moreover, the method was applied to an in vitro drug release (dissolution) test. The method was further extended to the determination of LOS in spiked human plasma. Statistical evaluation and comparison of data obtained using the proposed and comparison methods revealed no significant difference between the two methods in addition to good accuracy and precision for the proposed method. Copyright © 2013 John Wiley & Sons, Ltd.     

Green synthesis,characterization, enhanced functionality and biological evaluation of silver nanoparticles based on Coriander sativum

The present study focused on the green synthesis of silver nanoparticles from Coriander sativum (CS) containing structural polymers, phenolic compounds and glycosidic bioactive macromolecules. Plant phenolic compounds can act as antioxidants, lignin, and attractants like flavonoids and carotenoids. Henceforth, silver nanoparticles (AgNPs) were prepared extracellularly by the combinatorial action of stabilizing and reduction of the CS leaf extract. The biologically synthesized CS-AgNPs were studied by UV-spectroscopy, zeta potential determination, scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) analysis to characterize and confirm the formation of crystalline nanoparticles. The synthesized nanoparticles demonstrated strong antimicrobial activity against all microbial strains examined with varying degrees. The scavenging action on free radicals by CS-AgNPs showed strong antioxidant efficiency with superoxide and hydroxyl radicals at different concentrations as compared with standard ascorbic acid. The presence of in vitro anticancer effect was confirmed at different concentrations on the MCF-7 cell line as revealed with decrease in cell viability which was proportionately related to the concentration of CS-AgNPs illustrating the toxigenic nature of synthesized nanoparticles on cancerous cells.     

Molecular identification of Campanulotes bidentatus Scopoli, 1763 (Phthiraptera,Philopteridae) infecting the domestic pigeon Columba livia from Saudi Arabia

The taxonomy of the order Phthiraptera is unstable and still problematic to researchers. Most of the current taxon classifications are mainly based on morphological features. Campanulotes bidentatus belongs to the chewing lice of the Philopteridae family that mostly parasitic on birds. There is a lack of sequence data and phylogenetic analyses on the family Philopteridae. In the current study, C. bidentatus was collected from the domestic pigeon Columba livia and identified morphologically and molecularly based on the mitochondrial cytochrome c oxidase subunit 1 gene (COI). The infection rate of the Campanulotes genus was approximately 58.82% in this study. Phylogenetic analysis based on the mt COI gene was informative for members of Philopteridae and the group taxon genera formed distinct clades. Future studies were recommended using the 16s rRNA to enhance the tree topology and obtain clear differentiation between genera.     

Effects of nonsteroidal ecdysone agonist RH-5992 and chitin biosynthesis inhibitor lufenuron on <Emphasis Type="Italic">Spodoptera littoralis</Emphasis> (Boisduval, 1833)

Comparative studies of the effects of two compounds, tebufenozide (an ecdysone agonist) and lufenuron (an insect growth regulator inhibiting chitin synthesis), were conducted on Spodoptera littoralis (Boisduval, 1833). The compounds, orally administered, caused larval mortality proportional to the concentrations in the food source. Tebufenozide initiated precocious molting, and lufenuron, and inhibited chitin synthesis. In both cases, larvae were unable to complete the molting process and died in the old larval cuticle. Larvae contaminated by sublethal doses completed their development to adulthood. Lufenuron is more active than is tebufenozide. LD-50 for lufenuron is 0.0001ppm and for tebufenozide 0.001ppm. Topical application of the test compounds to eggs caused dose- and agedependent inhibition of embryonic development. Application of tebufenozide in the second half of embryogenesis caused precocious molting of eclosed larvae of the 1^st instar. Some morphological changes in the process of larval-pupal transformation were also observed. Tested compounds also reduced reproduction in adult individuals that had been treated by the tested compounds in the larval stage.     

Mass spectrometric characterization of circulating and functional antigens derived from piperacillin in patients with cystic fibrosis

A mechanistic understanding of the relationship between the chemistry of drug Ag formation and immune function is lacking. Thus, mass spectrometric methods were employed to detect and fully characterize circulating Ags derived from piperacillin in patients undergoing therapy and the nature of the drug-derived epitopes on protein that can function as an Ag to stimulate T cells. Albumin modification with piperacillin in vitro resulted in the formation of two distinct haptens, one formed directly from piperacillin and a second in which the dioxopiperazine ring had undergone hydrolysis. Modification was time and concentration dependent, with selective modification of Lys(541) observed at low concentrations, whereas at higher concentrations, up to 13 out of 59 lysine residues were modified, four of which (Lys(190), Lys(195), Lys(432), and Lys(541)) were detected in patients' plasma. Piperacillin-specific T lymphocyte responses (proliferation, cytokines, and granzyme B release) were detected ex vivo with cells from hypersensitive patients, and analysis of incubation medium showed that modification of the same lysine residues in albumin occurred in situ. The antigenicity of piperacillin-modified albumin was confirmed by stimulation of T cells with characterized synthetic conjugates. Analysis of minimally modified T cell-stimulatory albumin conjugates revealed peptide sequences incorporating Lys(190), Lys(432), and Lys(541) as principal functional epitopes for T cells. This study has characterized the multiple haptenic structures on albumin in patients and showed that they constitute functional antigenic determinants for T cells.     

Pectin induces apoptosis in human prostate cancer cells: correlation of apoptotic function with pectin structure

Treatment options for androgen-independent prostate cancer cells are limited. Therefore, it is critical to identify agents that induce death of both androgen-responsive and androgen-insensitive cells. Here we demonstrate that a product of plant cell walls, pectin, is capable of inducing apoptosis in androgen-responsive (LNCaP) and androgen-independent (LNCaP C4-2) human prostate cancer cells. Commercially available fractionated pectin powder (FPP) induced apoptosis (approximately 40-fold above non-treated cells) in both cell lines as determined by the Apoptosense assay and activation of caspase-3 and its substrate, poly(ADP-ribose) polymerase. Conversely, citrus pectin (CP) and the pH-modified CP, PectaSol, had little or no apoptotic activity. Glycosyl residue composition and linkage analyses revealed no significant differences among the pectins. Mild base treatment to remove ester linkages destroyed FPP's apoptotic activity and yielded homogalacturonan (HG) oligosaccharides. The treatment of FPP with pectinmethylesterase to remove galacturonosyl carboxymethylesters and/or with endopolygalacturonase to cleave nonmethylesterified HG caused no major reduction in apoptotic activity, implicating the requirement for a base-sensitive linkage other than the carboxymethylester. Heat treatment of CP (HTCP) led to the induction of significant levels of apoptosis comparable to FPP, suggesting a means for generating apoptotic pectic structures. These results indicate that specific structural elements within pectin are responsible for the apoptotic activity, and that this structure can be generated, or enriched for, by heat treatment of CP. These findings provide the foundation for mechanistic studies of pectin apoptotic activity and a basis for the development of pectin-based pharmaceuticals, nutraceuticals, or recommended diet changes aimed at combating prostate cancer occurrence and progression.     

A novel spectrofluorimetric method for determination of imatinib in pure,pharmaceutical preparation,human plasma,and human urine

The following paper represents a simple, highly sensitive, responsive validated and developed spectrofluorimetric method for estimation of imatinib (IMB) in its pure, commercial preparation, human urine and human blood plasma. The calibration curve was in the range 4–900 ng ml^?1 for pure form and urine and 8–900 ng ml^?1 for plasma in a medium contains carboxymethyl cellulose (CMC) and acetate buffer (pH 5) with excitation wavelength (λ_ex) 230 nm and emission wavelength (λ_em) 307 nm. The limit of detection (LOD) was 0.37 ng ml^?1 for the pure form, 0.64 ng ml^?1 for human urine, and 0.70 ng ml^?1 for human plasma, while the limit of quantitation (LOQ) was 1.2 for pure form, 1.91 for urine and 2.1 for plasma. The suggested method was successfully applied for evaluation of IMB in tablets within 99% mean percentage recovery. The excipients that are usually used as additives in pharmaceutical dosage form did not interfere with the suggested method. The method was efficiently used for estimation of IMB in human urine and human plasma. The effect of some cations that might be present in urine and plasma was also studied. The method was also focused on human volunteers and in vitro drug release.     

Mouse PSP94 expression is prostate tissue-specific as demonstrated by a comparison of multiple antibodies against recombinant proteins

Prostate tissue-specific gene expression is crucial for driving potentially therapeutic genes to target specifically to the prostate. Prostate secretory protein of 94 amino acids (PSP94), also known as beta-MSP (microseminoprotein), is one of the three most abundant secretory proteins of the prostate gland, and is generally considered to be prostate tissue-specific. We have previously demonstrated that the expression of the rat PSP94 gene is strictly prostate tissue-specific by an antibody against a recombinant rat PSP94. In order to study prostate targeting utilizing the PSP94 gene in a mouse pre-clinical experimental model, we need to establish antibodies against mouse PSP94 to confirm if it is prostate tissue-specific as well. In this study, firstly we raised a polyclonal antibody against a recombinant glutathione-S-transferase- (GST-) mouse mature form of PSP94. However, it showed very poor immunoreactivity against prostate tissue PSP94 as tested in Western blotting experiments. Neither antibodies against rat PSP94 nor mouse PSP94 showed significant cross-reactivity. Thus a second antibody was established against a recombinant mouse mature PSP94 containing N-terminal polyhistidines, and stronger immunoreactivity against mouse prostate tissue PSP94 was identified in Western blotting experiments. Both of these antibodies showed immunohistochemical reactivity, while the latter showed stronger reactivity in IHC when tested with different fixatives. By studying tissue distribution, we demonstrated that, as with rat PSP94, mouse PSP94 is strictly prostate tissue-specific in experiments of both Western blotting and immunohistochemistry (IHC). This conclusion was also derived from a comparison among antibodies against human, rat, and mouse PSP94, showing very different immunoreactivities in Western blotting and IHC. Finally, a competitive assay between different species was performed. We demonstrated that antibodies against PSP94 from different species (human, primate, rodents) have poor cross-reactivities. These observations also indicate that the PSP94 gene is a rapidly evolving gene in all species. Results from this study have led to the possibility of utilizing PSP94 as a targeting agent specifically to the prostate in a mouse experimental model.     

Prophylactic administration of carnosine and melatonin abates the incidence of renal toxicity induced by an over dose of titanium dioxide nanoparticles

The alleviative effects of two antioxidants, carnosine (Car) and melatonin (Mel), against titanium dioxide nanoparticles (TiO₂‐NPs) toxicity‐induced oxidative and inflammatory renal damage were examined in rats. Administration of these antioxidants along with TiO₂‐NPs effectively reduced serum urea, uric acid, creatinine, glucose, tumor necrosis factor‐α, interleukin‐6, C‐reactive protein, immunoglobulin G, vascular endothelial growth factor, and nitric oxide, as well as a significant amelioration of the decrease in glutathione levels in renal tissue was observed, compared to those in rats treated with TiO₂‐NPs alone. The renoprotective properties of the antioxidants were confirmed by reduced intensity of renal damage as demonstrated by histological findings. In conclusion, Car and Mel play protective roles against TiO₂‐NPs‐induced renal inflammation and oxidative injury, likely due to their antioxidant and anti‐inflammatory properties.     

Anti-microbiological activities of bio-synthesized silver Nano-stars by Saccharopolyspora hirsuta

A novel strain of Saccaropolyspora hirsuta was isolated from an insect Tapinoma simrothi for the first time and was morphologically and physiologically characterized. It was genetically identified using 16S rRNA and sequence similarity percentage in genbank with closely related species as strain ess_amA6 of Saccaropolyspora hirsuta. The accession number of strain ess_amA6 is KF996506. Antagonistic activity of strain ess_amA6 against some pathogenic Gram positive and negative bacteria, and unicellular fungus Candida albicans was studied. In addition, star shaped silver nanoparticles were biosynthesized using strain ess_amA6. The silver Nano stars were characterized by UV-us spectrophotometer. Fourier transform infrared spectroscopy analysis confirmed the conversion of Ag+ ions to Nano silver due to the reduction by capping material of extract. Transmission electron microscopically studies of biosynthesized Nano silver particles showed that they are spherical ranging from 10?nm to 30?nm in size. Silver atoms were checked in Nano sample by Energy Dispersive X-ray spectroscopy. Bioactivity of biosynthesized Nano silver was observed against some pathogenic microorganisms such as Staphylococcus aureus, Streptococcus pyogenes, Salmonella typhi, pseudomonas aeruginosa, Klebsiella pneumonia and Candida albicans. These tested microbes were highly sensitive to Nano silver. This study recommended that strain ess_amA6 can be used to effectively biosynthesize bioactive Nano silver compounds.