Paleobiogeographic implications of the Middle Eocene ostracods from Cairo–Suez district,Egypt

The main targets of this paper are to examine the Middle Eocene ostracod assemblages collected from a succession exposed in the Cairo–Suez district, Egypt and to detect their paleobiogeographical implications. The studied succession is subdivided into two rock units: the Observatory and Qurn formations, in ascending order. The analysis of the ostracod assemblages led to the identification of 18 species, none of which is new. Three local biozones are established, Digmocythere ismaili - Xestoleberis kenawyi Assemblage Zone, Grinioneis moosi - Loxoconcha pseudopunctatella Assemblage Zone and Cativella qurnenis - Soudanella triangulata Assemblage Zone. The multivariate analyses indicate that there are three distinct bioprovinces, one of them represents the North Africa bioprovince, including Egypt, Libya, and Tunisia. The second bioprovince represents the Middle East, including Jordan and Israel. The third represents the West Africa bioprovince, including Senegal, Togo, Ivory Coast and Nigeria. Therefore, this deduction supports a migration of Eocene ostracods along the southern Tethys.     

Synthesis,antimicrobial, anti-biofilm evaluation,and molecular modelling study of new chalcone linked amines derivatives

A series of amide chalcones conjugated with different secondary amines were synthesised and characterised by different spectroscopic techniques ¹H NMR, ¹³C NMR, and ESI-MS. They were screened for in vitro antibacterial activity. Compounds 36, 37, 38, 42, and 44 are the most active among the synthesised series exhibiting MIC value of 2.0–10.0?µg/ml against different bacterial strains. Compound 36 was equipotent to the standard drug Ampicillin displaying MBC value of 2.0?µg/ml against the bacterial strain Staphylococcus aureus. The products were screened for anti-biofilm activity. Compounds 36, 37, and 38 exhibited promising anti-biofilm activity with IC₅₀ value ranges from 2.4 to 8.6?µg. Molecular modelling was performed suggesting parameters of signalling anti-biofilm mechanism. AspB327 HisB340 (arene–arene interaction) and IleB328 amino acid residues seemed of higher importance to inhibit c-di-GMP. Hydrophobicity may be crucial for activity. ADME calculations suggested that compounds 36, 37, and 38 could be used as good orally absorbed anti-biofilm agents.     

Effect of dietary fish meal replacement by red algae, Gracilaria arcuata, on growth performance and body composition of Nile tilapia Oreochromis niloticus

A 12-week long feeding experiment was initiated to evaluate the effect of dietary supplementation of red algae, Gracilaria arcuata, on the growth performance, feed utilization and body composition of Nile tilapia Oreochromis niloticus (Linnaeus, 1758). The fish were fed with an algae-free control diet (C) and three experimental diets which replaced conventional fish meal with varying levels of dried G. arcuata (20%, 40% and 60%, represented as G20, G40 and G60, respectively). The growth parameters of final weight (FW), weight gain (WG), percentage of weight gain (WG%), daily growth rate (DGR) and specific growth rate (SGR) were significantly reduced (P < 0.05) at all levels of algae incorporation compared to the control diet. Moreover, the negative impact of Gracilaria meal on the growth performance of Nile tilapia increased as the proportion of algae in the diet increased, with fish on diet G20 exhibiting a significantly higher growth performance than the fish on either of the G40 and G60 diets. On the other hand, the feed utilization parameters feed conversion ratio (FCR) and protein efficiency ratio (PER) did not show significant differences between the fish in the control group and those on diet G20, although poorer FCR and PER outcomes were achieved in the case of fish on diet G60. The content of moisture, protein and ash in muscle and carcass increased as the proportion of Gracilaria meal in the diets increased, but the reverse was true for lipid level. These results indicate that incorporation of less than 20% red algae, Gracilaria arcuata, could be feasible in the diet of Nile tilapia and further studies are recommended to optimize the level of algae to improve growth performance.     

Scenedesmus obliquus: Antioxidant and antiviral activity of proteins hydrolyzed by three enzymes

Purpose

To obtain protein hydrolysates from fresh water green algae Scenedesmus obliquus by three different enzymes and evaluate its antioxidant and antiviral activity.

Mitigation of Acute Aluminum Toxicity by Sodium Selenite and N-Acetylcysteine in Adult Male Rats

The objective of this study is to investigate the toxic effects of aluminum and the potential alleviation of selenite and N-acetylcysteine (NAC) on this toxicity. Acute aluminum toxicity was induced by intraperitoneal (i.p.) injection of AlCl₃ (30 mg Al³⁺/kg) for four consecutive days. Al³⁺ damaged the synthetic capability and regeneration power of liver cells and induced inflammation. It also damaged the kidney and disturbed the lipid profile enhancing the total cholesterol level and LDL-cholesterol level increasing the risks of atherosclerosis. Al³⁺ reduced the cellular antioxidant milieu typified by the decrease in reduced glutathione, vitamin E, and four antioxidant enzymes and induced lipid peroxidation (LPO). Selenite at 1 mg Se/kg and NAC at 150 mg/kg injected either simultaneously with or after Al³⁺ mitigated most of these damaging effects probably by the virtue of scavenging the free radicals, binding aluminum and stimulating its excretion and reducing its bioavailability, bolstering the endogenous antioxidant defense systems, stabilizing the cell membrane, and preventing LPO. The beneficial effects of selenite and NAC against aluminum toxicity were also confirmed by the light and electron histopathology study. There were no significant differences between the two regimens used (protection and therapeutic) in the current study probably due to the short time of exposure, and the abrogation of Al³⁺ toxicity offered by selenite was better than that provided by NAC on the histopathology level.     

Prosomes (proteasomes) changes during differentiation are related to the type of inducer

The core of the 26S proteasome, the 20S prosome, is a highly organized multi-protein complex found in large amount in malignant cells. Differentiation of several cell lines, including the monoblastic U937 and the lymphoblastoid CCRF-CEM, is accompanied by a general decrease in the prosome concentration when phorbol-myrirtic-acetate (PMA) and retinoic acid plus dihydroxyvitamine D3 (RA+VD) are used. Incubation of U937 cells for three days with PMA or RA+VD causes differentiation, but the resulting patterns of prosome labeling in the cell and on the plasma membrane are not the same. In contrast, the same kind of prosome changes occur in U937 and CCRF-CEM cells when PMA is used as inducer. The intracellular distribution of prosomes is also linked to malignancy and differentiation. Prosomes are found in the nucleus and the cytoplasm of cancer cells; and treatment with RA+VD decreases the prosomes in the nucleus whereas PMA causes various prosome proteins changes. These results indicate that prosomes are important in cell regulation and in the expression of malignancy.     

Reactivity of metal chelates of sulphur containing ligands towards Lewis bases. Part III. Reaction of bis(1,2-dimethyl-and 1-phenyl-1,2-ethanediylidene)bis(S-methylhydrazinecarbodithioate)NN′SS′(−2)dizinc(II) with pyridines

The reaction of the dimeric zinc(II) chelates of the type I (R₁ = R₂ = CH₃, R₁ = H, R₂ = Ph) with pyridine, 2-methylpyridine, 3-methylpyridine and 4-methylpyridine afforded the monomeric monobase adducts. The isolated adducts were characterized by their electronic and ¹H NMR spectra, and a five coordinate square pyramidal structure was tentatively assigned for these adducts.The adduct formation reaction was followed spectrophotometrically and the reaction kinetics were studied using a stopped flow technique. From the available kinetic data, as well as the measured activated parameters (ΔH^#, ΔS^#), a mechanism for the adduct formation reaction is proposed.     

Evaluation of PCR Approaches for Detection of Bartonella bacilliformis in Blood Samples

BackgroundThe lack of an effective diagnostic tool for Carrion’s disease leads to misdiagnosis, wrong treatments and perpetuation of asymptomatic carriers living in endemic areas. Conventional PCR approaches have been reported as a diagnostic technique. However, the detection limit of these techniques is not clear as well as if its usefulness in low bacteriemia cases. The aim of this study was to evaluate the detection limit of 3 PCR approaches.Conclusions/SignificanceFrom the tested PCRs, the 16S rRNA PCR-approach is the best to be used in the direct blood detection of acute cases of Carrion’s disease. However its use in samples from dry blood spots results in easier management of transport samples in rural areas, a slight decrease in the sensitivity was observed. The usefulness to detect by PCR the presence of low-bacteriemic or asymptomatic carriers is doubtful, showing the need to search for new more sensible techniques.     

Morphology of Penicillium chrysogenum strains immobilized in calcium alginate beads and used in penicillin fermentation

Summary The morphology of two strains of Penicillium chrysogenum immobilized in calcium alginate and used in penicillin fermentation was examined. The degree and distribution of mycelial growth inside and on the surface of the beads depended on the strain, the cultivation media and the fermentation time. P. chrysogenum ATCC 12690 developed as a mycelial network inside the beads. The growth tendency of P. chrysogenum S₁ in micropellets was directed to the outer surface of the beads. At the end of the production phase only a trace of mycelia and no micropellets in the center of alginate beads were observed, while the outer surface and the subsurface were completely covered with mycelia.