In Vitro Schistosomicidal Activity of Phytol and Tegumental Alterations Induced in Juvenile and Adult Stages of Schistosoma haematobium.

There is renewed interest in natural products as a starting point for discovery of drugs for schistosomiasis. Recent studies have shown that phytol reveals interesting in vivo and in vitro antischistosomal properties against Schistosoma mansoni adult worms. Here, we report the in vitro antischistosomal activity of phytol against Schistosoma haematobium juvenile and adult worms and alterations on the tegumental surface of the worms by means of scanning electron microscopy. The assay, which was carried out with 6 concentrations (25, 50, 75, 100, 125, and 150 µg/ml) of phytol, has shown a promising activity in a dose and time-dependent manner. There was a significant decline in the motility of the worms and a mortality rate of 100% was found at 48 hr after they had been exposed to phytol in the concentration of 150 µg/ml. Male worms were more susceptible. On the ultrastructural level, phytol also induced tegumental peeling, disintegration of tubercles and spines in addition to morphological disfiguring of the oral and ventral suckers. This report provides the first evidence that phytol is able to kill S. haematobium of different ages, and emphasizes that it is a promising natural product that could be used for development of a new schistosomicidal agent.

Diagnostic and prognostic value of cell free circulating Schistosoma mansoni DNA: an experimental study.

Searching for a more sensitive and accurate marker for schistosomiasis diagnosis and treatment follow up is a potential necessity. Hereby, we evaluated usefulness of circulating free DNA as a marker for schistosomiasis diagnosis, assessing drug efficacy and monitoring the control interventions impact using SYBR green real-time PCR. A batch of mice were infected by 90 ± 10 Schistosoma mansoni cercariae. Starting from the 2nd day post infection (p.i.), groups of 2 or 3 mice were sacrificed every 3 days until 30 days p.i. The remaining animals were treated by a single dose of 400 mg/kg mefloquine and sacrificed in group at 5, 10, 21 days post treatment (35, 40, 51 days p.i.). Using SYBR green real time qPCR, pooled sera DNA were extracted and amplified. The results showed that, circulating free S. mansoni DNA was detected from the 2nd day post infection (p.i.) onwards with gradual decrease in the cycle threshold value Ct which indicates the gradual elevation of the DNA level (Log quantity was 2.6-3.1 IU/ml), As the infection progressed, DNA quantity was increased(Log quantity was 6.29 IU/ml). Initial increase of circulating free DNA was observed 10 days post treatment (40 days p.i.) (Log quantity was 7.38 IU/ml). That was followed by a progressive decrease in DNA level by the end of 21st day, post treatment (51 p.i.) (Log quantity 4.35 IU/ml). In conclusion, circulating free S. mansoni DNA is a reliable marker in the diagnosis of schistosomiasis and for assessing drug efficacy and monitoring the impact of control interventions.

Seropositivity of Toxoplasma gondii and Toxocara spp. in Children with Cryptogenic Epilepsy, Benha, Egypt.

The present study aimed to investigate the possible association of Toxoplasma gondii and Toxocara spp. infections with cryptogenic epilepsy in children. The study was carried out between June 2014 and March 2015. Total 90 children (40 with cryptogenic epilepsy, 30 with non-cryptogenic epilepsy, and 20 healthy control children) were evaluated to determine the anti-Toxocara and anti-T. gondii IgG seropositivity using ELISA kits. Epileptic cases were selected from those attending the pediatrics outpatient clinic of Benha University Hospital, Pediatrics Neurology Unit, and from Benha Specialized Hospital of children. The results showed that the level of anti-T. gondii IgG seropositivity was significantly higher among children with cryptogenic epilepsy (20%) than among children with non-cryptogenic children (0%). In healthy controls (10%), there was no association between toxocariasis seropositivity and cryptogenic epilepsy (only 5.7%; 4 out of 70 cases) among cases and 10% (2 out of 20) among controls. Among toxocariasis IgG positive cases, 3 (7.5%) were cryptogenic, and only 1 (3.3%) was non-cryptogenic. These statistically significant results support the association between T. gondii infection and cryptogenic epilepsy while deny this association with toxocariasis.

Dose-response relationship in Schistosoma mansoni juvenile and adult stages following limonin treatment in experimentally infected mice.

Preventive chemotherapy with praziquantel is the mainstay of schistosomiasis control. However, drug resistance is an imminent threat, particularly with large-scale administration of praziquantel, in addition to much less efficacy against young schistosomes. Several biological activities of limonin have been explored such as insecticidal, insect antifeedant, and growth-regulating activity on insects as well as antimalarial, antiviral, anticancer, cholesterol-lowering, and antioxidant activities. This study investigates limonin as an alternative antischistosomal compound using two novel, single, oral dose regimens. In the current work, the therapeutic efficacy of different limonin dosing protocols was evaluated in experimentally infected mice harboring Schistosoma mansoni (Egyptian strain) juvenile or adult stages. Oral administration of limonin in a single dose of 50 or 100 mg/kg on day 21 post-infection (p.i.) resulted in a significant worm burden reduction of 70.0 and 83.33 %, respectively. The same dose given on day 56 p.i. reduced total worm burdens by 41.09 and 60.27 %, respectively. In addition, significant reductions of 34.90 and 47.16 % in the hepatic and 46.67 and 56.1 % in the intestinal tissue egg loads, respectively, associated with significant alterations in the oogram pattern with elevated dead egg levels. Limonin produced ameliorations of hepatic pathology with reduction in dimensions and number of granulomas. Limonin also produced a variety of tegumental alterations in treated worms including tubercular disruption, edema, blebbing, and ulcerations. Results obtained by this work elucidated promising limonin bioactivity against S. mansoni juvenile and adult stages and provided a basis for subsequent experimental and clinical trials.

Effects of Thymus vulgaris ethanolic extract on chronic toxoplasmosis in a mouse model.

The current work was undertaken to investigate the potential effectiveness of Thymus vulgaris ethanolic extract (TVE) against Toxoplasma gondii infection in chronic experimental toxoplasmosis. To evaluate prophylactic effects, mice received 500 mg/kg TVE for 5 days before they were infected by an avirulent Me49 T. gondii strain. To investigate the therapeutic effects of the extract postinfection, daily treatment with TVE was initiated at 6 weeks postinfection and continued for 10 days. The following groups of animals were used as controls: uninfected/non-treated, infected/non-treated, and infected/treated with a combination of pyrimethamine and sulfadiazine. Brain cyst count and histopathological changes using H&E and Feulgen stains were used to evaluate the efficacy of TVE. The mean number of brain cysts was significantly decreased by 24 % in mice treated prophylactically with TVE. TVE also significantly reduced the mean number of brain cysts when administered to animals already chronically infected with T. gondii. The effect of TVE was comparable to that of treatment with a mixture of sulfadiazine and pyrimethamine (46 and 51 % reduction, respectively). Moreover, considerable amelioration of the pathological lesions in the brain and retina was observed. The results demonstrate the potential efficacy of T. vulgaris as a new natural therapeutic and prophylactic agent for use in the treatment of chronic toxoplasmosis.

Parasitic contamination of commonly consumed fresh leafy vegetables in benha, egypt.

This study evaluated the degree of parasitic contamination of vegetables which are commercialized and consumed fresh in Benha, Egypt. It included 530 vegetables: lettuce, watercress, parsley, green onion, and leek. Vegetables were collected randomly from markets within Benha. Samples were washed in saline, and the resulting washing solution was filtered and centrifuged to concentrate the parasitic stages. Sediments and supernatants were examined by iodine and modified Ziehl-Neelsen stained smears. Intestinal parasites were detected in 157/530 (29.6%) samples. Giardia lamblia cysts were the most prevalent parasite (8.8%) followed by Entamoeba spp. cysts (6.8%), Enterobius vermicularis eggs (4.9%), various helminth larvae (3.6%), Hymenolepis nana eggs (2.8%), Hymenolepis diminuta eggs (2.1%), and Ascaris lumbricoides eggs (0.6%). The highest contaminated vegetable was lettuce (45.5%) followed by watercress (41.3%), parsley (34.3%), green onion (16.5%), and leek (10.7%). These results indicate a significant seasonal variation (P < 0.05), with highest prevalence in summer (49%) and the lowest in winter (10.8%). These findings provide evidence for the high risk of acquiring parasitic infection from the consumption of raw vegetables in Benha, Egypt. Effective measures are necessary to reduce parasitic contamination of vegetables.

Predominance of Cryptosporidium parvum genotype among diarrheic children from Egypt as an indicator for zoonotic transmission.

Cryptosporidium is a genus of zoonotic pathogens transmissible from a variety of animals to humans and is a considerable public health concern. It is a significant cause of diarrheal disease in developing and industrialized nations. Cryptosporidium parvum and Cryptosporidium hominis are the main agents of cryptosporidiosis in humans. In this study we identified the genotypes of the Cryptosporidium isolates from clinical samples from diarrheic children using polymerase chain reaction (PCR) amplification and restriction fragment length polymorphism (RFLP) analyses of the TRAP-C2 gene (Thrompodin Related Adhesive Protein). A total of 430 fecal specimens from 1 to 14 years children were collected from inpatient and outpatient clinics of Benha University, Educational and Children Specialized Hospitals, Benha, Qalubyia, and were microscopically examined for Cryptosporidium spp. All infected samples were also analyzed using nested PCR. A polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis of the (266-366 bp) of TRAP-C2 gene was also used to detect and identify Cryptosporidium spp. in PCR- positive samples. The results showed that 50 (11.63%) of the specimens were positive for Cryptosporidium spp. Genomic amplification and restriction digestion of the PCR products by BstETI, Hae III for TRAP-C2 gene restriction enzymes revealed that 82% (41/50) had C. parvum, 12% (6/50) had C. hominis, and three (3/50) samples (6%) had mixed infections. In conclusion, elevated prevalence of C. parvum, suggesting animal-human (zoonotic) transmission and further investigations are required to determine the subgenotypes of C. parvum to clarify the mode of transmission in order to improve the control measures.

Comparative study between PCR and microscopic examination in diagnosing Entamoeba histolytica.

Differentiation between E. histolytica and non pathogenic species as Entamoeba dispar, which are morphologically identical species, is essential for rapid treatment decision, precaution of the invasive disease and public health. This study evaluated the real time PCR for detection of intestinal amoebiasis in comparison with microscopic examination. Stool samples were obtained from symptomatic 40 patients from outpatient clinic of Benha University Hospitals and Benha Educational Hospital. Twenty suffered from dysentery and 20 cases were not suffering dysentery. In addition 10 stool samples of other parasitic infection as Giardia lamblia and Cryptospordium parvum were examined by direct smear, iodine stained smear, formol ether concentration technique and real time PCR for detection of E. histolytica DNA. Formol ether concentration technique showed that 20 (40%) samples were positive for E. histolytica but real time PCR showed 26 (52%) positivity. All samples positive by microscopy were also positive by PCR and additional 6 PCR positive cases. There was no cross reaction with other parasites as G. lamblia and C. parvum.