Assessment of eugenol inhibitory effect on biofilm formation and biofilm gene expression in methicillin resistant Staphylococcus aureus clinical isolates in Egypt.

Methicillin-resistant Staphylococcus aureus (MRSA) biofilm infection is a major threat in Healthcare facilities. The search for biofilm inhibitors is essential to overcome the antibiotic resistance. Eugenol is a phyto-compound that possesses many biological properties. In this study, the aim was to estimate the effect of eugenol on biofilms of MRSA through quantifying the level of gene expression of three genes (IcaA, IcaD and SarA) involved in biofilm development.. Fifty MRSA biofilm producers collected from the microbiology lab at Theodor Bilharz Research Institute were incubated with different concentrations of eugenol for 24 h. The minimum inhibitory concentration of eugenol (MIC) that eradicates the biofilms growth was detected. mRNA was extracted from all isolates before and after the application of eugenol at 0.5 x MIC, and then subjected to quantitative real-time PCR (qPCR). Results showed that fourteen isolates out of 50 (28%) exhibited intermediate biofilm formation ability, and 36 out of 50 (72%) were strong biofilm producers. The MIC values of eugenol for MRSA ranged from 3.125% to 0.01%. The mean values of MIC in both strong and intermediate biofilm forming MRSA isolates were statistically comparable (p = 0.202). qPCR results revealed that the levels of expression of the studied genes IcaA, IcaD, and SarA were decreased after eugenol treatment when compared with their corresponding values before treatment (p = 0.001). Eugenol inhibited the formation of biofilm of MRSA isolates, indicating it could be used to control infections associated with MRSA biofilms.

Genomic instability in complicated and uncomplicated Egyptian schistosomiasis haematobium patients.

BACKGROUND: Exploration of genetic changes during active Schistosoma infection is important for anticipation and prevention of chronic sequelae. This study aimed to explore the genomic instability in chromosomal and cellular kinetics in Egyptians suffering from uncomplicated active schistosomiasis haematobium infection in addition to chronic schistosomiasis haematobium cases complicated by bilharzial-associated bladder cancer (BAC). RESULTS: This study was conducted on 46 schistosomiasis haemotobium cases, 22 were active (Viable S. haematobium eggs in urine samples as detected by microscopy) and 24 were chronic complicated with bladder cancer. Three cytogenetic techniques were applied; the first was quantitative nuclear-morphocytometry by means of which the Feulgen-stained nuclei were analyzed for parameters including shape, size, integrated optical-density and nuclear area. The second was Fluorescent In-Situ Hybridization (FISH) for specific p53gene-locus of chromosome 17 and the third technique was karyotyping. Concerning chronic complicated cases, the mean ± SD of DNA-content in urinary bladder tissue sections was 3.18 ± 0.65. Five samples (20.83%) of bladder tissue sections of chronic complicated cases showed diploid nuclei, 6 urinary bladder tissue samples (25%) were tetraploid, while 13 bladder samples (54.16%) were aneuploid. Epithelial cells of urine samples demonstrated aneuploidy (mean ± SD = 3.74 ± 0.36).Nuclear contents showed high proliferative DNA index in all urinary epithelial cells. In the acute uncomplicated group, nuclear-DNA of urinary epithelial cells was found diploid with mean nuclear-DNA content of 2.2 ± 0.16SD. Half of these diploid smears had a high proliferation index. The difference between nuclear DNA-contents in acute and chronic cases was significant (P = 0.0001). FISH technique for specific p53gene-locus and karyotyping were done on urinary bladder tissue specimens and peripheral blood monocytes of 8 chronic cases respectively. Three samples (37.5%) with invasive BAC had a deletion of the p53 gene. Karyotyping showed three cases out of the 8 chronic schistosomiasis haematobium patients with chromosomal fragmentations. CONCLUSIONS: DNA morphometry was valuable in detection of gross genetic changes in urothelial tissues. It is an important prognostic factor in established schistosomiasis haematobium induced bladder malignancy. It has the great advantage of being applicable on urine cells making it suitable for the prediction of a tendency towards genetic instability in active schistosomiasis haematobium patients.

Monoclonal antibody-based dipstick assay: a reliable field applicable technique for diagnosis of Schistosoma mansoni infection using human serum and urine samples.

A field applicable diagnostic technique, the dipstick assay, was evaluated for its sensitivity and specificity in diagnosing human Schistosoma mansoni infection. A monoclonal antibody (mAb) against S. mansoni adult worm tegumental antigen (AWTA) was employed in dipstick and sandwich ELISA for detection of circulating schistosome antigen (CSA) in both serum and urine samples. Based on clinical and parasitological examinations, 60 S. mansoni-infected patients, 30 patients infected with parasites other than schistosomiasis, and 30 uninfected healthy individuals were selected. The sensitivity and specificity of dipstick assay in urine samples were 86.7% and 90.0%, respectively, compared to 90.0% sensitivity and 91.7% specificity of sandwich ELISA. In serum samples, the sensitivity and specificity were 88.3% and 91.7% for dipstick assay vs. 91.7% and 95.0% for sandwich ELISA, respectively. The diagnostic efficacy of dipstick assay in urine and serum samples was 88.3% and 90.0%, while it was 90.8% and 93.3% for sandwich ELISA, respectively. The diagnostic indices of dipstick assay and ELISA either in serum or in urine were statistically comparable (P>0.05). In conclusion, the dipstick assay offers an alternative simple, rapid, non-invasive technique in detecting CSA or complement to stool examinations especially in field studies.

Diagnostic efficacy of monoclonal antibody based sandwich enzyme linked immunosorbent assay (ELISA) for detection of Fasciola gigantica excretory/secretory antigens in both serum and stool.

BACKGROUND: This research was carried out to develop a reliable monoclonal antibody (MoAb)-based sandwich enzyme linked immunosorbent assay (ELISA) for the diagnosis of active Fasciola gigantica infection in both serum and stool for comparative purposes. METHODS: From a panel of MoAbs raised against F. gigantica excretory/secretory antigens (ES Ags), a pair (12B/11D/3F and 10A/9D/10G) was chosen due to its high reactivity and strict specificity to F. gigantica antigen by indirect ELISA. RESULTS: The two MoAbs were of the IgG1 and IgG(2a) subclasses, respectively. Using SDS-PAGE and EITB, the selected MoAbs recognized 83, 64, 45 and 26 kDa bands of ES Ags. The lower detection limit of ELISA assay was 3 ng/ml. In stool, the sensitivity, specificity and diagnostic efficacy of ELISA was 96%, 98.2 and 97.1%; while in serum they were 94%, 94.6% and 94.3%, respectively. Moreover, a positive correlation was found between ova count in stool of F. gigantica infected patients and the OD readings of ELISA in both stool and serum samples (r = 0.730, p < 0.01 and r = 0.608; p < 0.01, respectively). CONCLUSIONS: These data showed that the use of MoAb-based sandwich ELISA for the detection of F. gigantica coproantigens in stool specimens was superior to serum samples; it provides a highly efficient, non-invasive technique for the diagnosis of active F. gigantica infection.

Fasciola gigantica: Parasitological and scanning electron microscopy study of the in vitro effects of ivermectin and/or artemether.

OBJECTIVE: To evaluate the in vitro effects of different concentrations of ivermectin and/or artemether on Fasciolagigantica worms and to study the parasitological changes and tegumental alterations using scanning electron microscopy (SEM). METHODS: Fasciola gigantica worms were incubated in vitro for 24 and 48 h with three concentrations of either ivermectin or artemether (10, 20 and 50 microg/ml) or both in half concentration of either (5, 10 and 25 microg/ml). RESULTS: Exposure of Fasciola worms to 25+25 microg/ml of combined drug regimens or to 50 microg/ml of either ivermectin or artemether for 48 h led to 100%, 41.7% and 75% worm killing which were accompanied by a significant reduction in egg laying capacity and significant increase in dead eggs maximally recorded in combined drug regimens. SEM of the flukes incubated for 48 h with combined drug regimens showed maximal tegumental disruption with swelling of the worm body, roughness, blebbing, sloughing and complete loss of spines. Disruption to the tegument of the flukes induced by artemether was more than that of ivermectin. CONCLUSIONS: Artemether alone or combined with ivermectin in half doses had potent fasciocidal activities. Besides, half doses of combined drug regimens had higher ovicidal effects than each drug alone. In vivo studies are recommended to explore the efficacy of combined regimens against Fasciola infection.