Towards a unified taxonomy

An interactive session entitled [Towards a unified taxonomy] was presented and settled in the 3[rd] Annual Conference of the Egyptian Parasitologists United EPU [Ain Shams Guest House; 10-11 October, 2012]. Taxonomy and the evolutionary interrelationships of parasites infective to human, remains a topic of debate. So, there is a pressing need to develop a consensus on the taxonomic classification scheme used in the curricula assigned for post-graduate students in all Egyptian Medical Parasitology Departments, with special emphasis on the protozoa

Cysteine proteases inhibitors [phenyl vinyl sulfone and valproic acid] in treatment of schistosomiasis mansoni-infected mice: an experimental study to evaluate their role in comparison to praziquantel

The emerged resistance to praziquantel [PZQ] in treatment of schistosomiasis necessitates the search for novel drugs. Cysteine proteases inhibitors [CPIs] have shown promising results in either parasitic infections or non-parasitic diseases. The study aimed to evaluate the therapeutic effects of two CPIs: phenyl vinyl sulfone [PVS] and valproic acid [VA] in comparison to PZQ in S. mansoni-experimentally infected mice. Swiss albino mice were experimentally infected with S. mansoni cercariae. The mice were divided into 4 groups [25 mice each], and G1 mice were not treated and used as control group. Mice of G2, G3 and G4 were treated by the evaluated drugs [PVS, VA and PZQ, respectively] at the end of the 6[th] week post infection [PI]. The evaluating parameters were 1] fecal egg count, 2] worm burden, 3] tissue egg count, 4] oogram pattern and 5] hepatic granuloma number and size. The results showed that by the end of 10[th] week PI, PZQ was the most effective drug resulting in decrease worm burden in the portal vein, increase proportion of dead eggs in the oogram pattern, decrease in the hepatic egg count and decrease in granuloma numbers. On the other hand, the granuloma diameter was smallest in PVS treated group compared to the other groups. CPIs have a relative fair favorable therapeutic outcome on schistosomiasis mansoni with the advantage of being novel drugs with no therapeutic resistance, especially PVS which showed an added specific anti-immunopathological effect reflected by the small hepatic granuloma size

Identification of antigenic epitopes of strongyloides stercoralis filariform larval antigen for immunodiagnosis of strongyloidiasis using western blot

Microscopic diagnosis of strongyloidiasis depending on detection of larvae in fecal samples is not sensitive, especially in asymptornatic patients, and development of reliable serological methods is imperative. Western blot [WB] technique showed promising results for the reactivity analysis in several parasitic infections. The objective of the present study is to identify relevant proteins of S. stercoralis filariform larvae [L3] using WB and a panel of serum samples for immunodiagnosis of strongyloidiasis. Material and S. stercoralis L3 were cultured from fecal samples of infected patients. The antigen was extracted and analyzed using SDS-PAGE. Sixty nine serum samples belonging to 3 groups of patients were analyzed and included in the study as: Group I [shedding S. stercoralis larvae in feces], group II [infected with other parasites], and group III [with negative parasitological results]. Reactivity of the resulting bands of S. stercoralis L3 antigen was analyzed with the serum samples using WB technique. Thirty four immunoreactive bands were detected in the WB analysis representing recognition of proteins with molecular weight [MW] varying from 19 to 214 kDa. Immunodominant proteins of 43, 41, 36, and 23/33 kDa were recognized respectively in 39%, 35%, 70% and 60% of sera from patients with confirmed strongyloidiasis; and in 29%, 21%, 21% and 30% of sera from those infected with other parasitic infections. One band [41 kDa] gave reaction with one serum sample from group III. It was concluded that the 43, 41, 36 and 32 kDa bands could be considered important tools for the development of diagnostic techniques for strongyloidiasis

Course specifications for parasitology courses: an overview experience in Suez Canal University

Faculty of Medicine, Suez Canal University [FOMSCU] received the first undergraduate students in 1981. Since then, FOMSCU applied an educational system with combined three lines; sell learning, community-based learning and integrated problem-based learning. There arc three phases; phase I [pre-pathogenesis], II [pathogenesis] and III [clinical]. However, academic as well as clinical sciences are given throughout the six years for graduation. Medical Parasitology Department started to apply the new curriculum for undergraduates in the academic year 2007/2008 for phase II [second and third years]. The new curriculum is bused on using the parasitological topics as main topic [core problem topic]. or side topic [related problem topic], or relevant topic. Each topic has its specific objectives [Intended Learning Outcomes; ILOs]. In addition, there are 3 main lectures given as introduction; 2 of them related to helminthes and protozoa [taught in the first weeks of year 2] and the third lecture is related to arthropods [taught in the first weeks of year 3]. The parasitological topics will be taught by several methods of instruction; problem solving, lecture, seminar, mini-talks and laboratory class. Regarding postgraduate students, beside the three main courses given to fulfill master and MD degrees and a subsidiary course to fulfill Microbiology and Immunology Master Degree, clinical departments [Clinical Pathology, Tropical Medicine and Community Medicine] have in their first part a Parasitology course. Traditional teaching methods provide systemic taxonolimic classification [Helminthology, Protozoology and Entomology]. For the first time. Medical Parasitology Department. FOMSCU provides a new clinical curriculum for each of these clinical master degrees. The new clinical curriculum is based on teaching parasitological topics relevant to the specialty

Possible mechanism[s] for cryptosporidial diarrhea: parasitologic and physiopathologic studies in experimental animals

The present work was planned to study the possible mechanism[s] of diarrhea in cryptosporidiosis Stool eluates and intestinal homogenates from naturally and experimentally infected animals together with purified sporozoites were examined utilizing using chamber to demonstrate their possible enterotoxic effects Besides the histopathological changes in experimentally infected mice were studied to assess the possible underlying mechanism[s] of diarrhea in cryptosporidiosis. Characterization of the enterotoxic activity associated with cryptosporidiosis may have a great impact on the development of effective strategies for its treatment. The results of the present study revealed that in intestinal cryptosporidiosis enterotoxic substances are secreted which likely induce diarrhea. They induce an increase in the transepithelial potential difference [DIsc] to reach its maximum after 15 minutes and then slowly decrease to reach the baseline after 55 minutes [for stool eluates] and 35 minutes [for intestinal homogenates] On the other hand the purified sporozoites showed an increase in DIsc after 9 minutes and then a decrease after that to become maintained at relatively high level. The enterotoxins were found to be time and dose dependent and heat labile. The osmotic gap showed that the mechanism of diarrhea is rather secretory. In experimentally infected mice, shedding of oocysts first appeared in stools 3 days postinoculation [PI], reaching a peak 9 days [PI] and disappeared 15 days PI. Although the infected mice showed mild to severe degree of intestinal inflammation [marked villous atrophy and crypts hyperplasia], the stool was semiformed. Besides, the present study showed marked validity of mouse as an in vivo model to study the pathophysiology of cryptosporidial diarrhea. This model is inexpensive and serves as a suitable alternative to neonatal calves for efficient oocyst propagation

Toxoplasma IgG and IgM antibodies among newborns in Port-Said city

The present study was carried out to detect the prevalence of congenital toxoplasmosis among the newborns delivered at Port-Said General Hospital, and to reveal some factors related to the spread of this infection. The study included 200 cord blood samples taken from the newborns immediately after delivery. A case sheet was taken from each case including full obstetric history of the mother together with complete clinical examination of the newborns. Each blood sample was analyzed for Toxoplasma IgG and IgM antibodies using ELISA. Positive cases for IgM antibodies were subjected to eye examination, skull X-ray, abdominal ultrasonography and CT scan for assessment of the clinical complications of congenital toxoplasmosis. It was found that 19 cases [9.5%] and 7 cases [3.5%] out of 200 cases were positive for IgG and IgM antibodies, respectively. Out of the IgM seropositive newborns, 4 cases showed pathognomonic complications in the form of either hydrocephalus, meningoencephalitis, ocular [convergence squint] and/or abdominal [jaundice and splenomegaly] manifestations. Statistical analysis of the factors related to toxoplasmosis revealed significant relation to contact of mothers with cats, their illness during pregnancy [fever and lymphadenopathy] and the occurrence of congenital anomalies in the newborns. It was concluded that congenital toxoplasmosis among newborns in Port-Said city is not uncommon, and search for IgG and IgM antibodies before and/or during pregnancy is recommended especially in high risk groups

Role of contact lenses in acanthamoeba keratitis

The present work was planned to study the role of contact lenses in Acanthamoeba keratitis. The study included two groups, 100 subjects each [contact lens and non-contact lens users]; 50% of each group were suffering from keratitis, while the others were asymptomatic. Ocular samples [corneal scrapings or swabs], contact lenses and lens care systems [storage containers and solutions] were examined for the presence of acanthamoeba using cultureand staining techniques. The isolation of acanthamoeba was achieved by the cultivation of the previous samples on non-nutrient agar overlaid with E. coliat 37C. Acanthamoebae were identified according to their morphological characters and the negative flagellation test. Acanthamoeba was identified in cultures of different specimens obtained from 20 subjects out of 200. The majority of acanthamoeba positive cases [90%] were contact lens users. Acanthamoeba was isolated more frequently from patients with keratitis and was not isolated from any asymptomatic non-contact lens users. Cultivation of the contact lenses was associated with high rate of acanthamoeba detection compared with the other sources of samples. From the present study, it was concluded that acanthamoebae are expected to be found in the contact lenses, their storage containers and rinsing solutions, which may predispose tokeratitis in contact lens users. Precise disinfection of contact lenses, cleaning of lens storage containers and the use of sterile rinsing solutions have a primary importance to prevent acanthamoeba contamination of contact lens care system