Mohamed Shaalan

Evaluation of hepatotoxic and genotoxic potential of silver nanoparticles in albino rats.

UNLABELLEDnSilver nanoparticles (AgNPs) have wide medical applications regarding their antimicrobial effects. They are applied also in appliances such as refrigerators and washing machines. For assessment of toxicological potential of silver nanoparticles 20 mature female albino rats were divided into four groups (five rats per each). Animals were injected i/p by different doses of approximately 8.7 nm silver nanoparticles (1, 2 and 4 mg/kg b.w) daily for 28 days in addition to control group which were injected by deionized water only. Indicators of oxidative stress in liver tissue, determination of silver nanoparticles tissue concentration, description of hepatic histopathological alterations and detection of possible chromosomal aberrations in bone marrow were carried out. Results revealed various hepatic histopathological lesions that were dose dependent. The effect of Ag-NPs on hepatic malondialdhyde (MDA) and glutathione (GSH) levels were variable in different treated groups compared with the control. The tissue residues of silver nanoparticles were found in hepatic tissue and related to original treated dose. Finally, silver nanoparticles induced variable chromosomal aberrations that were dose dependent.nnnCONCLUSIONnSilver nanoparticles had the ability for inducing various hepatic histopathological alterations indicating hepatocytotoxicity presumably by oxidative stress, in addition to the induction of chromosomal aberrations in bone marrow cells denoting the genotoxicity of nanosilver particles.

Recent progress in applications of nanoparticles in fish medicine: A review.

UNLABELLEDnNanotechnology has become an extensive field of research due to the unique properties of nanoparticles, which enable novel applications. Nanoparticles have found their way into many applications in the field of medicine, including diagnostics, vaccination, drug and gene delivery. In this review, we focused on the antimicrobial effects of nanoparticles, with particular emphasis on the problem of antibiotic resistant bacteria in fisheries. The use of nanoparticle-based vaccines against many viral pathogens is a developing field in fish medicine research. Nanoparticles have gained much interest as a specific and sensitive tool for diagnosis of bacterial, fungal and viral diseases in aquaculture. Nevertheless our review also highlights the many applications of nanotechnology that are still to be explored in fish medicine.nnnFROM THE CLINICAL EDITORnAdvance in nanotechnology has enabled the development of nanomedicine, with many ideas being used in clinical diagnosis and therapy. In this review article, the authors described the current use of nanotechnology in fish medicine. The knowledge would also impart important information for our daily living.

In vitro assessment of the antimicrobial activity of silver and zinc oxide nanoparticles against fish pathogens

BackgroundAntibiotic resistance is a global issue that threatens public health. The excessive use of antibiotics contributes to this problem as the genes of antibiotic resistance can be transferred between the bacteria in humans, animals and aquatic organisms. Metallic nanoparticles could serve as future substitutes for some conventional antibiotics because of their antimicrobial activity. The aim of this study was to evaluate the antimicrobial effects of silver and zinc oxide nanoparticles against major fish pathogens and assess their safety in vitro. Silver nanoparticles were synthesized by chemical reduction and characterized with UV–Vis spectroscopy, transmission electron microscopy and zeta sizer. The concentrations of silver and zinc oxide nanoparticles were measured using inductively coupled plasma-mass spectrometry. Subsequently, silver and zinc oxide nanoparticles were tested for their antimicrobial activity against Aeromonas hydrophila, Aeromonas salmonicida subsp. salmonicida, Edwardsiella ictaluri, Edwardsiella tarda, Francisella noatunensis subsp. orientalis, Yersinia ruckeri and Aphanomyces invadans and the minimum inhibitory concentrations were determined. MTT assay was performed on eel kidney cell line (EK-1) to determine the cell viability after incubation with nanoparticles. The interaction between silver nanoparticles and A. salmonicida was investigated by transmission electron microscopy.ResultsThe tested nanoparticles exhibited marked antimicrobial activity. Silver nanoparticles inhibited the growth of both A. salmonicida and A. invadans at a concentration of 17xa0µg/mL. Zinc oxide nanoparticles inhibited the growth of A. salmonicida, Y. ruckeri and A. invadans at concentrations of 15.75, 31.5 and 3.15xa0µg/mL respectively. Silver nanoparticles showed higher cell viability when compared to zinc oxide nanoparticles in the MTT assay. Transmission electron microscopy showed the attachment of silver nanoparticles to the bacterial membrane and disruption of its integrity.ConclusionsThis is the first study on inhibitory effects of silver and zinc oxide nanoparticles towards A. salmonicida and A. invadans. Moreover, zinc oxide nanoparticles inhibited the growth of Y. ruckeri. In low concentrations, silver nanoparticles were less cytotoxic than zinc oxide nanoparticles and represent an alternative antimicrobial compound against A. hydrophila, A. salmonicida and A. invadans.

Rapid identification of pathogenic streptococci isolated from moribund red tilapia (Oreochromis spp.)

Accurate and rapid identification of bacterial pathogens of fish is essential for the effective treatment and speedy control of infections. Massive mortalities in market-sized red tilapia (Oreochromis spp.) were noticed in mariculture concrete ponds in northern Egypt. Histopathological examination revealed marked congestion in the central vein of the liver with the presence of bacterial aggregates inside the lumen and in the vicinity of the central vein. A total of 12 isolates of streptococci were obtained from the moribund fish. This study documented the ability of the MicroSeq 500 16S bacterial sequencing method to accurately identify Streptococcus agalactiae and S. dysgalactiae mixed infections from moribund red tilapia that were difficult to be recognised by the commercial biochemical systems. The continuously decreasing cost of the sequencing technique should encourage its application in routine diagnostic procedures.

Particle Swarm Optimization and K-Means Algorithm for Chromosomes Extraction from Metaphase Images

This paper presents a novel approach based on hybrid particle swarm optimization and K-Means algorithm. The proposed approach is to remove residual stains and interphase cells from metaphase chromosome images to focus only on the chromosomes. Interphase cells can highly interrupt the automatic karyotyping. Karyotyping is the process that geneticist used for identifying chromosomal abnormalities to diagnose genetic diseases. The proposed approach comprised of three fundamental phases: (1) Preprocessing, (2) Image clustering based on hybrid particle swarm optimization and K-Means algorithm and (3) Interphase cells removal and chromosomes extraction phase. 40 chromosomal images from albino rat bone marrow are used in this experiment. The experimental results showed the efficiency of the proposed segmentation approach. It achieved overall almost 95% segmentation accuracy. Moreover, it compared with well-known approaches and gives better results.

Aquaculture in Egypt: Insights on the Current Trends and Future Perspectives for Sustainable Development

ABSTRACT Aquaculture has been practiced in Egypt for millennia, but modern approaches have only recently been adopted to maximize its output. Today, aquaculture production in Egypt is the largest in Africa with about one million tonnes per annum. In this review, different freshwater and marine fish species that are cultured in Egypt are reviewed; the most important species are the tilapias, followed by mullets and carps. Current practices for aquaculture in Egypt are highlighted, which include extensive, semi-intensive and intensive aquaculture systems, integrated aquaculture systems, aquaponics and rice-field aquaculture, desert aquaculture and mariculture. This review focuses on the constraints that threaten fast growing and sustainable development of aquaculture industry, such as production costs, availability of feed and seed, lack of current technologies for feed production and domestic regulations. Also, the future perspectives with regard to overcoming of these obstacles are presented.

Silver nanoparticles: Their role as antibacterial agent against Aeromonas salmonicida subsp. salmonicida in rainbow trout (Oncorhynchus mykiss)

The rise of bacterial resistance to antibiotics is one of the great challenges of our age. One of the strategies to limit the development of antibiotics resistance is the investigation of alternative antimicrobials. As silver nanoparticles demonstrated a potent bactericidal activity in vitro, the aim of this study was to evaluate the in vivo antibacterial activity of silver nanoparticles against Aeromonas salmonicida subsp. salmonicida. Rainbow trout (nu202f=u202f120) were divided into four groups of 30 fish each. First group was challenged with A. salmonicida (Positive control), the second group was challenged with A. salmonicida and exposed to silver nanoparticles by immersion for three hours (100u202fμg/L), the third group was challenged with A. salmonicida and intraperitoneally injected with silver nanoparticles (17u202fμg/mL) and the fourth group was sham-treated and served as a negative control group. At the 7th day post challenge, histopathology of the positive control group revealed the presence of bacterial aggregates in tissues with degenerative and necrotic changes, while at the 35th day post challenge, only liver necrosis persisted. Silver nanoparticles-treated and negative control groups did not show any clinical signs, mortalities or histopathological alterations and they were tested negative for A. salmonicida. The immersion in silver nanoparticles did not result in detectable residues of silver in the muscles 35u202fdays after treatment. These findings demonstrate the antibacterial properties of silver nanoparticles against A. salmonicida infection. Therefore, they could be used for development of antibacterial agents in aquaculture.

A Simple Approach for Segmentation and Removal of Interphase Cells from Chromosome Images

This paper proposes an approach for segmentation and removal of Interphase cells from chromosome images. The existence of undivided, condensed mass of chromosomes called Interphase cell, decrease the efficiency of automated karyotyping. Karyotyping is a process in which chromosomes in a dividing cell are identified and displayed in a standard format, that helps geneticist to diagnose genetic factors behind various genetic diseases.

Digital Pathological Services Capability Framework

Pathology digital lab is the modern, flexible and time effec- tive research assistant. The process of creating pathology slides contains five creation steps from the tissue samples collection till clearing and staining stage. The reservation and sharing of such slides using classical models limit the ability of pathologists to benefit from important and rare slides. The virtual lab with its digital slides conquers those limita- tions and adds more intelligence to research and diagnosis fields. Having the digital slides, it is easy to save, share, search, apply automatic di- agnosis through pattern recognition techniques, getting alerts for new slides and much more. The target of this work is to present the virtual lab design with its functionalities by explaining the glass slides creation process and then digitalize through scanners and the digital lab platform.