Physiological and biochemical studies on Egyptian fresh water algae

Summary Comparative study of the different methods of extraction and estimation of the algal nitrogenous constituents mainly proteins of an Egyptian strain ofChlorella ellipsoidea had been carried out. This study also involves the assay of the different fractions of the soluble nitrogenous compounds.     

Artonin E Induces Apoptosis via Mitochondrial Dysregulation in SKOV-3 Ovarian Cancer Cells

Artonin E is a prenylated flavonoid isolated from the stem bark of Artocarpus elasticus Reinw.(Moraceae). This study aimed to investigate the apoptotic mechanisms induced by artonin E in a metastatic human ovarian cancer cell line SKOV-3 in vitro. MTT assay, clonogenic assay, acridine orange and propidium iodide double staining, cell cycle and annexin V analyses were performed to explore the mode of artonin E-induced cell death at different time points. DNA laddering, activation of caspases-3, -8, and -9, multi-parametric cytotoxicity-3analysis by high-content screening, measurement of reactive oxygen species generation, and Western blot were employed to study the pathways involved in the apoptosis. MTT results showed that artonin E inhibited the growth of SKOV-3 cells, with IC₅₀ values of 6.5±0.5μg/mL after 72 h treatment, and showed less toxicity toward a normal human ovarian cell lineT1074, with IC₅₀ value of 32.5±0.5μg/mL. Results showed that artonin E induced apoptosis and cell cycle arrest at the S phase. This compound also promoted the activation of caspases-3, -8, and -9. Further investigation into the depletion of mitochondrial membrane potential and release of cytochrome c revealed that artonin E treatment induced apoptosis via regulation of the expression of pro-survival and pro-apoptotic Bcl-2 family members. The expression levels of survivin and HSP70 proteins were also down regulated in SKOV-3 cells treated with artonin E. We propose that artonin E induced an antiproliferative effect that led to S phase cell cycle arrest and apoptosis through dysregulation of mitochondrial pathways, particularly the pro- and anti-apoptosis signaling pathways.     

Plasma-Based Artificial Magnetic Conductor for Polarization Reconfigurable Dielectric Resonator Antenna

Plasmonics - Polarization reconfigurable dielectric resonator antenna (DRA) backed by plasma artificial magnetic conductor (AMC) ground plane is designed and optimized for 10-GHz applications. The...     

Optimization of the demineralization process for the extraction of chitin from Omani Portunidae segnis

Chitin is an organic polymer and it is the most frequent marine natural polysaccharide after cellulose. The main natural sources of chitin are exoskeletons of insects, mollusks, the cell walls of certain fungi and crustaceans such as crabs, shrimps and lobsters. The waste of these marine exoskeletons are pollutant for the environment, but these waste raw materials could be useful for production of commercial products like chitin. Chitin is an important raw material used for water treatment, agricultural, biomedical, biotechnological purposes, food and paper industry and cosmetics. Based on the variety of importance, the present targets of this study are to optimize the demineralization process for the removal of calcium and phosphate contents from the waste of Portunidae segnis (P. segnis) by using acid at ambient temperature and to characterize the isolated demineralized sample as well as the percentage of remaining calcium and phosphorus contents by using Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). The prepared waste carbs coarse powder samples of P. segnis were demineralized with seven different concentrations of hydrochloric acid at ambient temperature for 1 h. All the demineralization samples by the different concentrations were analyzed by using sensitive ICP-OES. The results based on ICP-OES showed that among the seven different concentrations used in the demineralization process for the isolation of chitin, the best was 2 M of HCl concentration for the production of chitin. The results also showed that the optimized concentration 2 M HCl gave the minimum concentration of calcium and phosphorus compared to other concentrations applied in this experiment. In conclusion, the optimized concentration for demineralization process could be used commercially for the isolation or commercial production of chitin for agricultural, biomedical and biotechnological purposes.     

Larvicidal potential of gold and silver nanoparticles synthesized using Acalypha fruticosa leaf extracts against Culex pipiens (Culicidae: Diptera)

Plant secondary metabolites have been recently used for the synthesis of different nanoparticles. The present investigation aimed at evaluating the effect of gold (AuNPs) and silver (AgNPs) nanoparticles synthesized using Acalypha fruticosa leaf extracts to control the mosquito Culex pipiens. The A. fruticosa AuNPs and AgNPs spectra displayed their maximum absorption at 550 nm and 440 nm, respectively. The infrared spectra revealed different functional groups related to different chemical compounds. The larval mortality of aqueous leaf extract of A. fruticosa was 499.54 ppm (LC₅₀) and 1734.06 ppm (LC₉₀) after 24 h of treatment. This study revealed that AuNP (LC₅₀, 30.2 and LC₉₀, 104.83 ppm) and AgNP (LC₅₀, 52.86 and LC₉₀, 157.227 ppm) preparations were highly effective compared to the A. fruticosa extract alone and also more affordable, as a smaller amount was required. The present findings show the potential larvicidal effect of the synthesized AuNPs and AgNPs for the control of mosquito-mediated disease transmission.     

Association of the myosin heavy chain 9 gene single nucleotide polymorphism with inflammatory bowel disease

BackgroundTo date, the cause of inflammatory bowel disease (IBD) remains a mystery. A balance between cell proliferation and apoptosis maintains intestinal tissue homeostasis. Dissociation-induced myosin-actin contraction results in stem cell apoptosis. This study aiming to evaluate the influence of the myosin heavy chain 9 (MYH9) gene single nucleotide polymorphisms (SNPs) on inflammatory bowel disease.Subjectsand methods: The study carried on eighty patients with IBD and seventy controls. All participants subjected to history taking, thorough physical examination, colonoscopy and laboratory investigations. Genotyping performed for rs4821480 and rs3752462 by SNP assay real-time PCR methods.ResultsOn analyzing rs3752462 CT and TT genotypes were significantly more frequent in IBD patients as compared to controls with 4.6 fold increase in the risk of IBD. While on analyzing rs4821480, The TG and GG genotypes have significant increased distribution among the IBD patients as compared to the controls with 5.3 fold increase in the risk of IBD and higher prevalence of GG genotype in patients with low hemoglobin level and higher BMI.ConclusionThe rs3752462 T allele and rs4821480 G allele of MYH9 are associated with more susceptibility to IBD.     

PDZK1 Is a Novel Factor in Breast Cancer That Is Indirectly Regulated by Estrogen through IGF-1R and Promotes Estrogen-Mediated Growth

Although a relationship between PDZK1 expression and estrogen receptor (ER)-α stimulation has been suggested, the nature of such a connection and the function of PDZK1 in breast cancer remain unknown. Human tissue microarrays (cancer tissue: 262 cores; normal tissue: 87 cores) and breast cancer cell lines were used to conduct the study. We show that PDZK1 protein expression is tightly correlated with human breast malignancy, is negatively correlated with age and had no significant correlation with ER-α expression levels. PDZK1 exhibited an exclusive epithelial expression with mostly cytosolic subcellular localization. Additionally, 17β-estradiol induced PDZK1 expression above its basal level more than 24 h after treatment in MCF-7 cells. PDZK1 expression was indirectly regulated by ER-α stimulation, requiring insulinlike growth factor 1 receptor (IGF-1R) expression and function. The molecular link between PDZK1 and IGF-1R was supported by a significant correlation between protein and mRNA levels (r = 0.591, p < 0.001, and r = 0.537, p < 0.001, respectively) of the two factors in two different cohorts of human breast cancer tissues. Interestingly, PDZK1 knockdown in MCF-7 cells blocked ER-dependent growth and reduced c-Myc expression, whereas ectopic expression of PDZK1 enhanced cell proliferation in the presence or absence of 17β-estradiol potentially through an increase in c-Myc expression, suggesting that PDZK1 has oncogenic activity. PDKZ1 also appeared to interact with the Src/ER-α/epidermal growth factor receptor (EGFR) complex, but not with IGF-1R and enhanced EGFR-stimulated MEK/ERK1/2 signaling. Collectively, our results clarify the relationship between ER-α and PDZK1, propose a direct relationship between PDZK1 and IGF-1R, and identify a novel oncogenic activity for PDZK1 in breast cancer.     

Synthesis of Acyclovir and HBG Analogues Having Nicotinonitrile and Its 2-methyloxy 1,2,3-triazole

Reaction of pyridin-2(1H)-one 1 with 4-bromobutylacetate (2), (2-acetoxyethoxy)methyl bromide (3) gave the corresponding nicotinonitrile O-acyclonucleosides, 4 and 5, respectively. Deacetylation of 4 and 5 gave the corresponding deprotected acyclonucleosides 6 and 7, respectively. Treatment of pyridin-2(1H)-one 1 with 1,3-dichloropropan-2-ol (8), epichlorohydrin (10) and allyl bromide (12) gave the corresponding nicotinonitrile O-acyclonucleosides 9, 11, and 13, respectively. Furthermore, reaction of pyridin-2(1H)-one 1 with the propargyl bromide (14) gave the corresponding 2-O-propargyl derivative 15, which was reacted via [3+2] cycloaddition with 4-azidobutyl acetate (16) and [(2-acetoxyethoxy)methyl]azide (17) to give the corresponding 1,2,3-triazole derivatives 18 and 19, respectively. The structures of the new synthesized compounds were characterized by using IR, ¹H, ¹³C NMR spectra, and microanalysis. Selected members of these compounds were screened for antibacterial activity.     

Characterization and kinetic properties of the purified Trematosphaeria mangrovei laccase enzyme

The properties of Trematosphaeria mangrovei laccase enzyme purified on Sephadex G-100 column were investigated. SDS–PAGE of the purified laccase enzyme showed a single band at 48 kDa. The pure laccase reached its maximal activity at temperature 65 °C, pH 4.0 with K_m equal 1.4 mM and V_max equal 184.84 U/mg protein. The substrate specificity of the purified laccase was greatly influenced by the nature and position of the substituted groups in the phenolic ring. The pure laccase was tested with some metal ions and inhibitors, FeSO₄ completely inhibited laccase enzyme and also highly affected by (NaN₃) at a concentration of 1 mM. Amino acid composition of the pure enzyme was also determined. Carbohydrate content of purified laccase enzyme was 23% of the enzyme sample. The UV absorption spectra of the purified laccase enzyme showed a single peak at 260–280 nm.