Botany And Microbiology Dept

Changes in growth and ultrastructure of Azolla caroliniana in response to elevated UV-B
radiation were investigated. Exposure of plants to UV-B radiation for 1, 8, 16, 24 and 48 h
exhibited a significant decrease in biomass and relative growth rate. This decrease resulted
in an increase in doubling time over the control. Also, Chl a and b contents were significantly
decreased especially after 16 h. The reduction was accompanied by a decrease in 5-aminolaevulinic
acid content (precursor of chlorophyll). On the other hand, contents of carotenoid
and UV-absorbing phenolic compounds (flavonoids and anthocyanins) were increased.
Key words: Doubling Time, Relative Growth Rate, UV-Absorbing Compounds

The ultrastructure of chloroplast and quantified antioxidant compounds such as α-tocopherol, ascorbic acid and beta carotene, semi quantitatively by comparing the peak areas of HPLC chromatograms, were affected considerably in response to exposure of Azolla caroliniana to UV-B radiation for 24 and 48 h. The results show that the most striking effect of the enhanced UV-B treatment on the ultrastructure of A. caroliniana was observed after 48 h as markedly widened chloroplast area occupied by large amount of plastoglobuli in stressed fronds. Prolonged UV-B exposure of A. caroliniana for 48 h resulted in a reduction in peaks area for for αtocopherol, ascorbic acid and beta-carotene. The results show that changes in the chromatogram of non-enzymatic antioxidants were correlated with the duration of exposure to UV-B radiation. These antioxidant metabolites play a vital role in protecting A. caroliniana to a certain limit against UV-B radiation.

Deposition effect of cement dust on pigmentation was studied in Zygophyllum coccineum, Salsola tetrandra, Cyperus conglomeratus, Limonium axillare and Suaede vermiculata. Measurements were taken for plants in two cites , one close to early constructed cement factory at (Jeddah, Saudi Arabia) about 500 meters and other one far from the factory about 5 kilometers. The rate of mortality of young branches were high in the area subjected to the cement dust in all five species, whereas Salsola tetandra and Suaede vermiculata are the most sensitive among them. Unless Cyperus conglomerotus, It is noted that amount of chl a, b and carotenoids in all investigated plants that are far away from cement dust more than that near from the factory. Carbohydrates and protein contents are significantly decreased in non polluted Salsola tetandra and Suaeda vermiculata, whereas these parameters increased significantly parallel to the dust accumulation rate on plants near to the factory. In general, pollution by the cement dust has caused adverse effects on the photosynthetic pigments, the pH of the cell sap, metabolism of soluble amino acids and soluble sugars.

ABSTRACT Deposition effect of cement dust on pigmentation was studied in Zygophyllum coccineum, Salsola tetrandra, Cyperus conglomeratus, Limonium axillare and Suaede vermiculata. Measurements were taken for plants in two cites, one close to early constructed cement factory at (Jeddah, Saudi Arabia) about 500 meters and other one far from the factory about 5 kilometers.

ABSTRACT Chilling associated oxidative damage that enhanced the production of reactive oxygen species (ROS), slow down metabolism and modify membranes resulting in lipid peroxidation. A marked increase in the level of H2O2 was estimated in alfalfa leaves after dark chilling treatment and as a consequence, oxidation damage due to H2O2 accumulation could cause lipid peroxidation of membrane and result in a significant increase in malondialdehyde (MDA) content.

Software architecture is a key discipline in software engineering as it performs a central role in many modern software development paradigms. For an evolving complex architecture, assessing the change impact for the components considering all maintenance scenarios is a difficult problem. In this paper, we present a methodology to conduct sensitivity analysis of maintainability-based risk factors for software architectures. The methodology can assist the software architect to determine the components with the least ...

Complex formation of the tetradentate ligand bis (2-picolyl) glycine, BPG, with both Zn (II) and Cu (II) ions in aqueous solution was investigated spectroscopically by using 1 H NMR and UV-visible titrations as well as electrochemically by using cyclic voltammetry. Analysis of the titration data indicated that the aqua complexes [BPG-Zn (OH2) 2]+ 1 and [BPG-Cu (OH2) 2]+ 2 deprotonate at pH= 10.6 and 9.7. The catalytic hydrolysis of the activated phosphate ester tris (p-nitrophenyl) phosphate (TNPP) by using these model complexes ...

Three transition metal-bound thiolate complexes [LZn-SC6H5]+ 1,[LCu-SC6H5]+ 2, and [LCo-SC6H5]+ 3, derived from the tetradentate ligand N, N', N"-tris (p-hydroxybenzylaminoethyl) amine, L were synthesized and characterized as functional models for the active site of thiolate alkylating enzyme. Solid state studies of these model complexes were investigated using infrared spectroscopy and both thermal and elemental analyses. The methylation reactions of these thiolate complexes were found to be the ...

Bioprosthetic valve thrombosis is an extremely rare event, therefore, long-term anticoagulation can be avoided. There is limited experience in the diagnosis and treatment of such a situation. We present the case of a patient with a porcine mitral bioprosthesis who presented with acute pulmonary edema, likely secondary to obstructive valve thrombosis. A favorable outcome was observed after conservative anticoagulant treatment.

The chemical similarity of antibacterial cyclic peptides and peptidomimetics was studied in order to identify new promising cyclic scaffolds. A large descriptor space coupled with cluster analysis was employed to digitize known antibacterial structures and to gauge the potential of new peptidomimetic macrocycles, which were conveniently synthesized by acylbenzotriazole methodology. Some of the synthesized compounds were tested against an array of microorganisms and showed antibacterial activity against Bordetella bronchistepica, Micrococcus luteus, and Salmonella typhimurium.

Synthetic approaches to gabapentin bioconjugates that overcome the tendency of gabapentin to cyclize into its c-lactam are studied. Gabapentin was converted by N-acylation at its N-terminus into di-, tri-, and tetrapeptides (L-Ala-Gbp, L-Val-Gbp, L-Ala-L-Phe-Gbp, Gly-L-Ala-b-Ala-Gbp). Carboxyl-activated Boc-protected gabapentin was used to N-, O-, and S-acylate small peptides and hormones to give conjugates that could also provide prodrugs containing conformationally constrained gabapentin units. (A.R. Katritzky). NH O 1 2a O OH H 2 N Scheme 1. Intramolecular cyclization of gabapentin (Gbp) into 2-azaspiro[4,5]decan-3-one 2a.

Quaternary carbolinium salts have been reported to show improved antimalarial activity and reduced cytotoxicity as compared to electronically neutral β-carbolines. In this study mono-and dimethylated quaternary carbolinium cations of manzamine A were synthesized and evaluated for their in vitro antimalarial and antimicrobial activity, cytotoxicity and also their potential for glycogen synthase kinase (GSK-3β) inhibition using molecular docking studies. Among the analogs, 2-Nmethylmanzamine A (2) exhibited antimalarial activity (IC 50 0.7 -1.0 µM) but was less potent than manzamine A. However the compound was significantly less cytotoxic to mammalian kidney fibroblasts and the selectivity index was in the same range as for manzamine A.

a b s t r a c t A new ligand, namely, N-{tris([2-[(1-methylbenzimidazol-2-yl)ethyl]methyl]amino)-2-oxoethyl}iminodiacetic acid is synthesized and characterized and used to prepare a zinc complex as a promising model for the active site of the nacreous protein in mollusc shells. Preliminary investigation of CO 2 fixation and calcification is studied with regard to the influence of the pK a value of the coordinated water molecule and the carboxylate groups. (M. M. Ibrahim).

This study was designed to assess the safety, tolerability, and efficacy of intravenous infusion of CA4P in patients with neovascular age-related macular degeneration (AMD). Prospective, interventional, dose-escalation clinical trial. Eight patients with neovascular AMD refractory to at least 2 sessions of photodynamic therapy received CA4P at a dose of 27 or 36 mg/m2 as weekly intravenous infusion for 4 consecutive weeks. Safety was monitored by vital signs, ocular and physical examinations, electrocardiogram, routine laboratory tests, and collection of adverse events. Efficacy was assessed using retinal fluorescein angiography, optical coherence tomography, and best corrected visual acuity (BCVA). The most common adverse events were elevated blood pressure (46.7%), QTc prolongation (23.3%), elevated temperature (13.3%), and headache (10%), followed by nausea and eye injection (6.7%). There were no adverse events that were considered severe in intensity and none resulted in discont...

To assess oxygen saturation (StO2) in retinal vessels of normal subjects and diabetic patients with and without retinopathy using the modified version of the Flow Oximetry System (FOS) and a novel assessment software. The FOS and novel assessment software were used to determine StO2 levels in arteries and veins located between 1 and 2 mm from the margin of the optic disc and in the macular area. Eighteen normal subjects, 15 diabetics without diabetic retinopathy (DM no DR), and 11 with non-proliferative diabetic retinopathy (NPDR) were included in final analysis. The mean [± standard deviation (SD)] StO2 in retinal arteries was 96.9%±3.8% in normal subjects; 97.4%±3.7% in DM no DR; and 98.4%±2.0% in NPDR. The mean venous StO2 was 57.5%±6.8% in normal subjects; 57.4%±7.5% in DM no DR; and 51.8%±6.8% in NPDR. The mean arterial and venous StO2 across the three groups were not statistically different (P=0.498 and P=0.071, respectively). The arterio-venous differences between the three s...

Background: The National Eye Institute 39-Question Visual Function Questionnaire (NEI VFQ-39) is an indicator of vision-related quality of life (QoL). The NEI VFQ-39 is used to assess the QoL in patients with non-infectious posterior uveitis, intermediate uveitis, or panuveitis, treated with subconjunctival (SCJ) or intravitreal (IVT) sirolimus as an immunomodulatory therapeutic (IMT) agent, delivered subconjunctivally (SCJ) or intravitreally (IVT) (the SAVE Study). Thirty subjects with non-infectious uveitis were randomized (SCJ:IVT, 1:1) for a prospective clinical trial. The 39-Question Visual Function Questionnaire (VFQ-39) was administered at baseline (BL), month 6 (M6), and month 12 (M12) visits. The survey measures self-reported vision health status for patients with chronic eye disease and assesses the effects of visual impairment on both task-oriented visual function and general health domains. In accordance to the NEI-VFQ Manual, each patient's questionnaire was converted to a scaled score between 0 (worst) and 100 (best), and median scores were calculated for each of the subcategories and overall composite score at BL, M6, and M12. Wilcoxon signed-rank test was performed. Results: Twenty-six patients completed the VFQ-39 at BL and M6, whereas 23 patients completed it at M12. Patients showed a significant improvement in pooled composite scores from BL to M6 and BL to M12. Analysis by treatment groups showed that intravitreal injection of sirolimus is better tolerated. Conclusions: Sirolimus has demonstrated bioactivity as an IMT and corticosteroid-sparing agent to treat non-infectious uveitis. Patients receiving intravitreal injection of sirolimus showed overall improvement of vision-related health while those receiving subconjunctival injections did not. Larger randomized control trials with sirolimus are indicated to validate these results.

Soil contamination with petroleum hydrocarbon products such as diesel and engine oil is becoming one of the major environmental problems. This study describes hydrocarbons degrading bacteria (PHAD) isolated from long-standing petrol polluted soil from the eastern region, Dammam, Saudi Arabia. The isolated strains were firstly categorized by accessible shape detection, physiological and biochemistry tests. Thereafter, a technique established on the sequence analysis of a 16S rDNA gene was used. Isolation of DNA from the bacterial strains was performed, on which the PCR reaction was carried out. strains were identified based on 16Sr DNA sequence analysis, As follows amplified samples were spontaneously sequenced automatically and the attained results were matched to open databases. Among the isolated bacterial strains, S1 was identified as Staphylococcus aureus and strain S1 as Corynebacterium amycolatum.