Objective  This article evaluates the antibacterial and remineralization potential of experimentally prepared toothpastes containing different mixtures of nano casein phosphopeptides (nCPP), nano amorphous calcium phosphate (nACP), probiotic ­ Lactobacillus rhamnosus B-445 ( L. rhamnosus ), and nano glycomacropeptide (nGMP). Materials and Methods  Five experimental toothpaste samples were prepared and grouped, such that group (A0) was the experimental toothpaste base formula. Groups (A1), (A2), (A3), and (A4) were the experimental toothpastes containing: nCPP; nCPP and nACP; nCPP, nACP, and L. rhamnosus , and nCPP, nACP, and nGMP, ­respectively. Group (A5) was the commercial group (GC MI Paste Plus). The five groups were screened against Streptococcus mutans (ATCC 25175) growth, and investigated for their remineralizing potentials on demineralized bovine enamel using Vickers ­microhardness test (Vickers hardness number [VHN]). Scanning electron microscope (SEM) images were obtained for the demineralized and remineralized enamel of the two most effective toothpastes against in vitro bacterial induced enamel demineralization. Statistical analysis was performed using one-way analysis of variance (ANOVA) as well as repeated measures ANOVA followed by Tukey’s post hoc test. Results  Both (A3) and (A4) were significantly higher in mean inhibition zone ­diameters than group (A1) and (A2). Group (A4) showed the highest statistical ­significance in the mean difference between VHN values of demineralization and 15 days remineralization period. SEM images showed the deposition of nano-sized particles fill the ­microrough surface pattern of the etched enamel. Conclusion  All these findings suggest the use of probiotic, nCPP–nACP, and nGMP as a dental anticariogenic and remineralizing active agents.

No abstract

In a view of increasing the role of Aeromonas spp. in fish and human diseases, the present wok was conducted to assay the presence of six virulence genes using PCR in Aeromonas species isolated from fishes and water of Manzala Lake. A total of 200 fish samples comprising 100 Oreochromis niloticus fish, 100 Mugil cephalus fish and 50 water samples were collected from El Gamil region in Lake Manzala. A total number of 258 isolates belonging to Aeromonas spp. were recovered from fish and lake water samples and they were biochemically identified into 4 biotypes. PCR assay of 15 representatives, biochemically confirmed Aeromonas spp. isolates showed that they were genetically confirmed belonging to genus Aeromonas based on specific16S rRNA gene sequence. Virulence properties of the 15 representative strains showed that the majority of the examined strains carried one or more virulence genes. A significant 5 virulence gene have been found in the tested Aeromonas isolates. The frequencies distribution of these genes was aero (100%), act (20%), ahcytoen (13.33%), lip (13.33%), alt (6.67%). Meanwhile, Haemolysin (hly) gene could not be detected in any of examined Aeromonas isolates.

No abstract

A total of 70 Aeromonas isolates isolated from 100 Oreochromis niloticus, 100 Mugil cephalus and 50 water samples from El Gamil region in Manzala Lake were investigated for antibiotic susceptibility test to 14 different antimicrobial agents using disc agar diffusion method. All strains showed (100%) sensitivity to norfloxacin and showed high sensitivity to cefotaxime (91.4%), gentamycin (90%), nalidixic acid (80%), amikacin (78.6%) and chloramphenicol (74.3%). On the other hand, all tested isolates were resistant to ampicillin, erythromycin and penicillin and they exhibited high resistance rate to vancomycin (94.3%) and doxycycline (91.4%). Multiple antimicrobial resistance (MAR) index values of the tested isolates were higher than 0.2. They were 0.38, 0.36, 0.36 and 0.37 for A. hydrophila, A. sobria, A. caviae and A. schubertii, respectively.