Green synthesis of silver and iron oxide nanoparticles mediated photothermal effects on Blastocystis hominis.

The evolution of parasite resistance to antiparasitic agents has become a serious health issue indicating a critical and pressing need to develop new therapeutics that can conquer drug resistance. Nanoparticles are novel, promising emerging drug carriers that have demonstrated efficiency in treating many parasitic diseases. Lately, attention has been drawn to a broad-spectrum nanoparticle capable of converting absorbed light into heat via the photothermal effect phenomenon. The present study is the first to assess the effect of silver nanoparticles (Ag NPs) and iron oxide nanoparticles (Fe3O4 NPs) as sole agents and with the combined action of the light-emitting diode (LED) on Blastocystis hominins (B. hominis) in vitro. Initially, the aqueous synthesized nanoparticles were characterized by UV-Vis spectroscopy, zeta potential, and transmission electron microscopy (TEM). The anti-blastocyst efficiency of these NPs was tested separately in dark conditions. As these NPs have a wide absorption spectrum in the visible regions, they were also excited by a continuous wave LED of wavelength band (400-700 nm) to test the photothermal effect. The sensitivity of B. hominis cysts was evaluated using scanning laser confocal microscopy whereas the live and dead cells were accurately segmented based on superpixels and the k-mean clustering algorithm. Our findings showed that this excitation led to hyperthermia that induced a significant reduction in the number of cysts treated with photothermally active NPs. The results of this study elucidate the potential role of photothermally active NPs as an effective anti-blastocystis agent. By using this approach, new therapeutic antiparasitic agents can be developed.

Possible Correlation between Giardia duodenalis Genotypes and Fecal Calprotectin in Children with Diarrhea.

Background: Giardiasis is one of the leading causes of diarrhea, particularly among children under the age of five in developing countries. Fecal calprotectin (FC) is an important biomarker for diagnosis and monitoring of inflammtory bowel disease, but other diagnoses should be considered in light of its elevation. We aimed to evaluate FC level in patients diagnosed with giardiasis and elucidate a possible correlation between Giardia genotypes and FC levels. Methods: Overall, 120 fecal samples were collected from children aged 4-12 years and tested for giardiasis by light microscopy. Out of which, 50 samples were enrolled within two groups: group I "cases" and group II "controls" and then subjected to PCR amplification, sequencing of the beta-giardin (bg) gene of the parasite, and FC evaluation. Results: Assemblage B was identified in 75%, and assemblage A in 25% of samples. FC levels were statistically elevated in "group I" in comparison to "group II". Likewise, there was a statistically significant difference between FC levels in patients infected with assemblage A and assemblage B with a mean of 114 µg/gm and 202 µg/gm, respectively. Conclusion: The study highlighted the possible association between Giardia genotype B and elevated FC levels, further detailed studies are necessary to clarify these finding.

Growth kinetics, antigen profiling, and proteinase activity of Egyptian Trichomonas tenax isolates derived from patients having oral infections.

The role of Trichomonas tenax as a pathogen had been clearly implicated in various pathological processes that arise outside the boundaries of the mouth. Although a relationship between the increased occurrence of this protozoan and progression of periodontal disease has been demonstrated, the ability of T. tenax in causing oral infections and the precise mechanism of tissue damage is not well known. The present study aimed to investigate different isolates of T.tenax from individuals having oral infections. Plaques and/or calculi samples were collected from 70 individuals who were diagnosed as having periodontitis and/or gingivitis, then subjected to parasitological examination and culture on modified trypticase, yeast and iron medium (TYI-S-33). Isolates successfully maintained in culture were further subjected to analysis of protein profile of lysates by Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE) and analysis of proteinases by non-denaturing gelatin-SDS-PAGE. Comparison of growth kinetics of seven T. tenax isolates showed a wide variability in the growth characteristics. Protein profiles of the seven isolates revealed a total 53 bands ranged in molecular weight (MW) from 5 to 95kDa using 12% resolution gel. Also, T. tenax isolates were found to possess 19 proteinase bands ranged in MW from 14 to 66kDa. The proteolytic bands were intensified by a cysteine proteinase activator and totally disappeared by treatment with a cysteine proteinase inhibitor suggesting that the proteinases were of cysteine proteinases type. The high frequency of T. tenax detected (28.6%) along with the variability in protein profiling and proteolytic activity of the isolates supports the possible pathogenicity of T. tenax and clarifies a conclusion that different strains with possibility of variable pathogenic potential may exist.