Evaluation of the potential cardioprotective activity of some Saudi plants against doxorubicin toxicity

Doxorubicin (DOX) is an anthracycline antibiotic widely used as a chemotherapeutic agent in the treatment of several tumours. However, its cardiac toxicity limits its use at maximum therapeutic doses. Most studies implicated increased oxidative stress as the major determinant of DOX cardiotoxicity. The local Saudi flora is very rich in a variety of plants of quite known folkloric or traditional medicinal uses. Tribulus macropterus Boiss., Olea europaea L. subsp. africana (Mill.) P. S. Green, Tamarix aphylla (L.) H. Karst., Cynomorium coccineum L., Cordia myxa L., Calligonum comosum L' Hér, and Withania somnifera (L.) Dunal are Saudi plants known to have antioxidant activities. The aim of the current study was to explore the potential protective effects of methanolic extracts of these seven Saudi plants against DOX-induced cardiotoxicity in rats. Two plants showed promising cardioprotective potential in the order Calligonum comosum > Cordia myxa. The two plant extracts showed potent in vitro radical scavenging and antioxidant properties. They significantly protected against DOX-induced alterations in cardiac oxidative stress markers (GSH and MDA) and cardiac serum markers (CK-MB and LDH activities). Additionally, histopathological examination indicated a protection against DOX-induced cardiotoxicity. In conclusion, C. comosum and C. myxa exerted protective activity against DOX-induced cardiotoxicity, which is, at least partly, due to their antioxidant effect.     

Studies on bacterioplankton and inhibitory strains of aquatic actinomycetes in Lake Bardawil,Egypt

Lake Bardawil represents a hyper-saline shallow (50–600 cm deep) water basin lying along the northern shore of Sinai. Surface water samples were collected monthly from this lake for physico-chemical and microbiological analysis. Seasonal variations in the averages of temperature, pH and transparency of the tested water samples were determined. Seasonal averages of the total bacterial counts at 22 and 37°C, biovolumes of cells and bacterial biomass of the lake’s water at different regions were also determined. In addition to the gram-negative pathogen, Edwardsiella tarda, faecal contamination indicators, total coliforms, faecal coliforms and faecal streptococci were counted in the lake’s water samples from various regions during different seasons. The number of actinomycetes per milliliter of the lake’s water samples were determined. Fifteen actinomycetes were isolated and screened for their antibacterial activity against E. coli and pathogenic E. tarda isolated from the same water samples. Five isolates of these actinomycetes showed antibacterial activities and nine of them were identified as Streptomyces. The most antibacterially active isolate was subjected to morphological, physiological and biochemical studies and identified as Streptomyces viridiviolaceus. The identified organism exhibited antimicrobial activities against the main indicator of water pollution, E. coli, pathogenic E. tarda, Corynebacterium michiganese B-33, Pseudomonas solanacearum B-3212 and Staphylococcus. No antimicrobial activities were recorded against Bacillus cereus, Micrococcus, Mycobacterium, Aspergillus niger, Candida albicans, C. tropicalis or Rhizopus nigricans.     

Neo-clerodane diterpenoids from teucrium yemense

The aerial parts of Teucrium yemense yielded four new neo-clerodane diterpenoids, namely, 6β-O-acetyl-3β-hydroxyteucroxylepin, teucryemin, 19-O-acetylteucryemin and teucryeminone, in addition to the known flavone cirsiliol. The structures of the new compounds were elucidated from their spectral data, by chemical derivatization and by comparison with closely related compounds.     

Photosynthetic Characteristics of Cassava (Manihot esculenta Crantz), a C3 Species with Chlorenchymatous Bundle Sheath Cells

Cultivars of cassava, Manihot esculenta Crantz, were studiedto determine the mechanism of photosynthetic carbon assimilationin this species. The results, contrary to recent reports, indicatethat cassava is a C₃ plant based on a number of physiologicaland biochemical photosynthetic characteristics. The CO₂ compensationpoints among 10 cassava cultivars ranged from 55 to 62 µlliter^–1, which was typical for C₃ plants including castorbean, a member of the same family (Euphorbiaceae). The initialproducts of photosynthesis in cassava are C₃-like; the activitiesof several key C₄ enzymes in cassava are low and similar tothose of C₃ plants. Data on the rates of photosynthesis perunit of leaf area and the photosynthetic response of cassavato CO₂ is also consistent with C₃ photosynthesis. Cassava hasa distinctive chlorenchymatous vascular bundle sheath locatedbelow a single layer of palisade cells. Unlike C₃-C₄ intermediatesand C₄ species, the bundle sheaths of cassava are not surroundedby mesophyll cells. The bundle sheath cells which occur at highfrequency in cassava may function in both photosynthesis andtransport of photosynthates in the leaf. (Received July 31, 1990; Accepted September 25, 1990)     

Growth regulators influence the fatty acid profiles of in vitro induced jojoba somatic embryos

Inducing somatic embryogensis from jojoba [Simmondsia chinensis (Link) Schneider] explants to produce artificial seeds in the laboratory (in vitro) may prove highly profitable, as the seeds contain a characteristic liquid wax of economic importance in industry, nutrition and medicine. Thus, there is a need to examine the effect of the factors involved in the in vitro process on the quality and quantity of the synthesized fatty acids in comparison with those naturally produced in vivo. Immature zygotic embryos and mature leaf explants were cultured on Murashige and Skoog basal medium (MS) supplemented with various levels of 2,4-D, BA and sucrose. Embryogenic calluses developed from the zygotic embryos and leaf explants over a period of 2–4 weeks with the highest response at 0.4 μM 2,4-D, 2.2/4.4 μM BA and 117 mM sucrose (4%). Following induction, the zygotic embryo derived somatic embryos developed to the globular, heart, torpedo, and cotyledon stages. Direct somatic embryogenesis was observed with some of the zygotic embryo explants. Leaf-derived embryogenic calluses did not mature on any of the maturation/germination media examined up to 4 weeks of culture. Analysis of fatty acids indicated that the mature seeds are characterized with long chain saturated fatty acids C22:0 behenic Acid. The zygotic embryo-derived somatic embryos (SE-Z) and leaf-derived somatic embryos (SE-L) are characterized with the induction of the essential polyunsaturated fatty acid C18:2 (omega-6) linoleic acid, (omega-3) alpha-linolenic acid (ALA), with higher values of long chain saturated fatty acids C16:0 palmitic acid and monounsaturated fatty acid C18:1 oleic acid. These results indicate that manipulating the growth regulators in the induction media influenced the fatty acids synthesis and hence the fatty acids profile in jojoba somatic embryos.     

Telepathology in emerging countries pilot project between Italy and Egypt

Pathological examination includes gross & microscopic examinations at different magnification. Through the steps of examination, we obtain many images that can be used for telepathology. Telepathology is the practice of pathology at a distance, viewing images on a monitor rather than directly through a light microscope. It can be used for primary diagnosis, second opinion, quality assurance and distance learning. Telepathology is classified into Static, Dynamic, Hybrid and Whole Slide Imaging (WSI). We have a successful experience in Egypt in applying the static & dynamic techniques in a pilot project between the Italian Hospital in Cairo (NPO) and the Civico Hospital in Palermo. This project began in 2003 and continued till now. From the second year 2004, Ospedale S. Giovanni e Paolo Hospital in Venice, Charing Cross Hospital in London and the University of Pittsburgh Medical Center Health System (UPMC) in the USA participated actively in our project. During the past five years we consulted on many problematic pathological cases with these different specialized pathological centers in Italy, UK & USA. In addition to the highly specialized scientific value of consulting on the cases and exchanging knowledge, we saved a lot of time and money and succeeded in providing our patients with a better medical service.We are now in the process of establishing a Digital Telepathology Center (DTC) in the pathology department, Cairo University, using the latest technique of telepathology which is Whole Slide Imaging (WSI). We believe that it will help us to improve and extend diagnosis for our difficult pathological cases and will facilitate increased E-learning opportunities for staff and students both in Egypt and in the longer term in the wider Eastern Mediterranean.     

Probing for submandibular gland peptide-T receptors on leukocytes with biotinylated-Lys-[Gly](6)-SGP-T

Nonviral gene transfer vectors have been actively studied in the past years in order to obtain structural entities with minimum size and defined shape. The final size of a gene transfer vector, which is compacted into unimolecular complexes, is directly proportional to the mass of the nucleic acid to be compacted. Thus, the purpose of this study was to assess the possibility of producing ssDNA vectors and their biophysical and biological characterization. We have obtained ssDNA/poly-L-lysine complexes that are significantly smaller than their double-stranded counterparts. We have also identified a lesser aggregative behavior of compacted single-stranded vs. double-stranded DNA vectors in the presence of physiological NaCl concentrations. Expression of compacted ssDNA is observed in hepatoma cell lines. Moreover, we have successfully delivered galactosylated ssDNA complexes into cells that express the asialoglycoprotein receptor via receptor-mediated endocytosis. The reduced size and biophysical behavior of ssDNA vectors may provide an advantage for transfection of eukaryotic cells.     

Vasculature in pre-blastema and nerve-dependent blastema stages of regenerating forelimbs of the adult newt, Notophthalmus viridescens

Immunocytochemistry utilizing a monoclonal antibody (BV1; blood vessel 1) highly reactive to the vasculature of the adult newt showed that a developing vasculature was present during early, pre-blastema, and early-bud blastema stages of forelimb regeneration in this species. Infusion of Prussian Blue and DiI into the brachial artery further delineated the intactness of this early vasculature. Finally, macroscopic observations of vascular flow underneath the apical epithelial cap (AEC) and microsurgical removal of the AEC and observation of subsequent bleeding buttressed the conclusion that an intact vasculature exists during early nerve-dependent stages of newt forelimb regeneration. The results suggest that this process of neovascular formation is angiogenesis, i.e., the formation of new vessels from pre-existing vessels in the stump. Furthermore, angiogenesis is an ongoing process initiated early after amputation. Blastema cells and the AEC are likely sourcesof factors that stimulate neovascularization.     

Effects of sub-lethal concentrations of synthetic insecticides and Callitris glaucophylla extracts on the development of Aedes aegypti.

Synthetic and botanical insecticides can have a profound effect on the developmental period, growth, adult emergence, fecundity, fertility, and egg hatch, resulting in effective control at sub-lethal concentrations. This paper investigated sub-lethal concentrations of fenitrothion, lambda-cyhalothrin, and Callitris glaucophylla Joy Thomps. & L.P. Johnson (Cupressaceae) extract to characterize their effects on the development of Aedes aegypti L. (Diptera: Culicidae) mosquito larvae. The LC25, LC50, and LC75 (four replicates) were used for each synthetic insecticide and the LC25 and LC75 (four replicates) were used for C. glaucophylla. Observations of larval mortality, duration of larval stage, pupal mortality, duration of pupal stage, adult emergence, sex ratio, and malformations were recorded over 14 days. A dose-response effect was observed for all insecticides. Although C. glaucophylla extract doses were higher than synthetic insecticide doses, the LC75 treatment outperformed synthetics by completely prohibiting adult emergence. Consequently, this botanical is recommended for field application either in combination with synthetic or natural insecticides or alone.     

Mitochondria Bound to Lipid Droplets Have Unique Bioenergetics,Composition, and Dynamics that Support Lipid Droplet Expansion

1. Download high-res image (208KB)
2. Download full-size image