Nanomedicine is defined as application of nanotechnology for treatment, monitoring, prevention, and control of biological diseases. To apply nanomedicine, the precise targets (cells and/or receptors) specific to the clinical disease should be identified and the suitable nanoparticles for delivery system to minimize the side effects of the original drug should be selected. One of these precise targets are macrophages, endothelial, dendritic as well as tumor cells. The main aim of the present review is to throw light on possible nanotechnology applications in parasitic diseases focusing on three main aspects: diagnosis, treatment, and vaccination.

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Background Toxoplasmosis is a widespread disease caused by the opportunistic parasite Toxoplasma gondii, with variable overall prevalence according to the different geographical areas. Blood donors pose as possible contributors for transfer of infection. Objective The aim of this study was to estimate the prevalence of exposure to Toxoplasma in blood donors using sensitive techniques in a cross-sectional study. Materials and methods An aggregate of 150 blood donors from the blood donation center of Alexandria University participated in this study. The blood samples were tested for the presence of T. gondii immunoglobulin (Ig) G antibody and target gene B1 using enzyme-linked immunosorbent assay and real-time PCR, respectively. Results Of 150 participants, 65.3% tested were positive for anti-Toxoplasma IgG, and 10% showed parasitemia as B1 gene was successfully amplified in nine seropositive samples and in six seronegative samples. Conclusion The recorded IgG seropositivity in this selected group of individuals may be considered an indication of the general prevalence of toxoplasmosis in Alexandria. Detected parasitemia using real-time PCR draws attention to the possibility of transmission through blood transfusion even from seronegative donors and emphasizes the importance of specialized Toxoplasma DNA screening before donation of blood.

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Background Major symptoms associated with blastocystosis include diarrhea, abdominal pain, fatigue, constipation, flatulence, urticaria, and skin rash. It may play a significant role in several chronic gastrointestinal illnesses such as irritable bowel syndrome (IBS). Objective The main objective was to identify Blastocystis spp. subtypes (STs) of clinical isolates obtained from three different groups of patients: IBS and non-IBS with and without gastrointestinal tract symptoms. The secondary objective was to evaluate the infectivity and pathogenicity of detected STs from each group in experimental rats. Patients and methods This study was designed as a case-control study. Stool samples were collected from patients attending Suez Canal University Hospitals. Only positive samples for Blastocystis spp. were included in the study and the three groups were identified (19 patients each). Blastocystis spp. STs were identified using seven pairs of primers (SB83, SB155, SB227, SB332, SB340, SB336, and SB337) to explore the relationship of different STs with different clinical presentations of each group. Detected STs, from each group, were then used to evaluate the infectivity and pathogenicity in experimentally infected rats monitored by parasitological and histopathological parameters. Results STs using seven different sequence-tagged site primers revealed 54 isolates with single infection and three isolates with mixed infection. ST3 was the most common one in the present sample of Egyptian population (56.1%) followed by ST1 (35.1%), then ST2 (3.5%), whereas 5.3% were mixed infection (ST1 and ST3). Conclusion Our results showed that the clinical outcome of blastocystosis is not likely associated with a specific ST, although some STs are predominant in other epidemiologic studies.

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Heat shock proteins (HSPs) are highly conserved and immunogenic proteins that are shared among diverse groups of mammals and microbial agents. They are categorized into different families according to their molecular weight. HSPs are involved in a variety of cellular processes and essential to cell survival. They are also implicated in immune pathology and clinical manifestations of a variety of autoimmune diseases and/or metabolic disorders such as atherosclerosis, diabetes and systemic lupus erythematosus. Their role in antigen cross-presentation and cancer immunotherapy as well as initiators of immune response and targets of autoimmune attack was also reported. The objectives of the current presentation are to summarize the functional properties of HSPs and their role in innate and acquired immune responses, to throw light on their role in pathogenesis and parasites survival, to review the literature searching for new drug discovery and vaccine candidates for parasitic diseases, and finally to present their use in diagnosis and genotyping of some parasitic diseases. Heat shock proteins (HSPs) are highly conserved and immunogenic proteins that are shared CONTENTS Introduction 1. Functional Properties of HSPs 1.1. Innate immunity 1.2. Adaptive immunity: 1.3. HSPs as cancer vaccines: 1.4. HSPs as infectious disease vaccines 1.5. HSPs and apoptosis 2. Heat Shock Proteins and Helminthes 2.1. Schistosoma spp. 2.2. Echinococcus spp. 2.3. Strongyloides spp. 2.4. Trichinella spiralis 2.5. Filarial nematodes 2.6. Other helminthes Concluding Remarks References Abbreviations: APC: Antigen-presenting cell; CTL: Cytotoxic T-lymphocyte; E/S: Excretory/secretory; gp96: a member of HSP90 family; GST: Glutathione-S-transferase; HC: Hydatid cyst; HSP: Heat shock protein; IFN: Interferon; IL: Interleukin; MHC: major histocompatibility complex; NK: Natural killer; SEA: Soluble egg antigen; TLR: Toll-like receptor; TGF: Transforming growth factor; TNF: Tumor necrosis factor.

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Background The protozoan parasite Giardia intestinalis is a common childhood infection in developing countries that causes diarrheal illness. The majority of G. intestinalis isolates from humans are grouped into two distinct genetic assemblages A and B. The molecular epidemiological studies on G. intestinalis assemblages in humans are limited in Egypt. Objective This study was conducted to estimate the detection rate of G. intestinalis infection among a cohort of children suffering from diarrhea in the Dakahalia governorate, Egypt, and to correlate between clinical giardiasis and Giardia spp. assemblages in positive stool samples by PCR-restriction fragment length polymorphism (PCR-RFLP). Participants and methods A total of 311 diarrheal stool samples were examined microscopically for Giardia spp. infection. DNA samples were isolated from the stools of 103 (33.12%) positive samples with G. intestinalis, amplified with PCR, and digested with the XhoI enzyme for RFLP. Results Of the 103 samples, 64 (62.14%) were found to be assemblage B, whereas 32 samples (31.07%) belonged to assemblage A. Mixed genotype A and B was present in three samples (2.91%), and four samples (3.88%) were of undetermined Giardia spp. assemblage. The detection rate of assemblage B was higher in samples from children with persistent diarrhea, whereas assemblage A detection rate was higher in samples from acute diarrhea. Conclusion G. intestinalis causing diarrhea in children in the Dakahalia governorate, Egypt, predominantly belongs to assemblage B, indicating that human-to-human method of infection is more common than zoonotic method.

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Background Acquiring trichinellosis while traveling abroad is not a new phenomenon and imported cases are regularly reported worldwide. Cases contracted abroad and reported by the French National Reference Centre for Trichinella (NRCT) are analyzed here. Results Since 1998, 28 imported cases, representing 37% of all cases, were reported to the NRCT, with a mean annual incidence of two cases. Between 1975 and 1998, 40 imported cases represented only 1.5% of all identified cases, but with a comparable mean annual incidence of 1.6 cases. The incidence of imported cases could even have decreased since 1998 as the number of international travelers increased during that period. Since 1998, most cases were acquired in Canada from bear meat (hunters). Some cases were acquired in West Africa from warthog meat, in Laos from pork, and one case, in Algeria, was because of the consumption of jackal meat. Discussion These imported cases are most likely to occur in countries where the habit of eating raw meat is common and may show a high transmission in some regions where the disease is or had become unknown (e.g. Senegal, Laos, etc.). Backpackers, adventure travelers, or hunters will certainly be at a higher risk and should be informed about the risks of eating raw meat (pork, game, or reptile meat) and should be discouraged from illegally importing potentially infected meat that could introduce the parasite in Trichinella-free areas. Conclusion Travelers can be good indicators of the emergence of the parasitosis in a given country. Imported cases are good indicators of the epidemiology of the disease in countries where the original infection occurred.

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Background The vast majority of human cases of cryptosporidiosis worldwide are caused by two species: Cryptosporidium hominis (C. parvum type 1), which causes infection in humans only, and Cryptosporidium parvum (C. parvum type 2), which causes infections in humans and animals. In Egypt, calves carrying the zoonotic C. parvum represent the largest farm animal source of infection for humans. Information on the source of Cryptosporidium spp. contamination is necessary for effective evaluation and selection of management practices for reducing the risk for cryptosporidiosis. Objective The aim of the study was to genotypically characterize Cryptosporidium spp. in a sample of isolates from calves and children suffering from diarrhea. Materials and methods One hundred stool samples were collected from diarrheic calves housed at the Tropical Diseases Clinic, Faculty of Veterinary Medicine, Cairo University. A total of 110 stool samples were also collected from diarrheic children attending the Gastroenteritis Unit, Abo El Reesh Pediatric Hospital, Cairo University. Each stool sample of children or calves was examined microscopically after staining with modified Ziehl-Neelsen stain for the diagnosis of Cryptosporidium spp. Positive samples were then subjected to nested PCR-restriction-fragment length polymorphism (PCR-RFLP) targeting Cryptosporidium oocyst wall protein (COWP) gene for determination of Cryptosporidium genotypes. Results Screening by modified Ziehl-Neelsen staining detected Cryptosporidium in stools of 40% of diarrheic calves. Nested PCR-RFLP analysis showed that all positive samples were related to C. parvum genotype 2 (C. parvum). In diarrheic children, screening diagnosed 12/110 (10.9%) positive cases; 9/12 (75%) of them were confirmed positive by nested PCR. RFLP analysis showed that 8/9 (88.9%) samples were C. parvum genotype 1 (C. hominis), whereas one sample was not digested. Conclusion Genotype 2 C. parvum is relatively highly prevalent in the sample of calves examined compared with genotype 1 in the sample of children, indicating that transmission of cryptosporidiosis among this sample of children is anthroponotic and not zoonotic. It is advised to include PCR-RFLP technique in routine clinical diagnosis and epidemiological investigations.

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Strongyloides stercoralis can cause hyperinfection syndrome and disseminated disease with high mortality, particularly in an immunocompromised patient. With the low diagnostic rate of S. stercoralis on stool examination, early endoscopic biopsy and histopathologic diagnosis of strongyloidiasis must be taken into consideration when examining duodenal biopsies from immunocompromised patients, to avoid the development of life-threatening infection.

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Background Giardiasis is an important common intestinal infection that occurs as a result of ingestion of cysts of the protozoan parasite Giardia lamblia. Several medications are available to treat giardiasis. Metronidazole and other chemical drugs currently used for treatment cause side effects, whereas ginger has been used for centuries as a herbal medicine, without harmful side effects. Objective With regard to the above-mentioned properties of ginger we were prompted to evaluate its anti-Giardia activity, as compared with nitazoxanide (NTZ) and phosphate buffer saline (PBS) as controls, and to establish a G. lamblia axenic culture that yields a large number of trophozoites. Materials and methods Fresh clinical isolates of G. lamblia were obtained from different patients with acute giardiasis. Trophozoites were cultured using Stone’s modification of Locke’s solution as an axenic culture medium modified by supplementing with bovine bile and heat-inactivated bovine serum. Ginger extract was prepared to give a final concentration of 20 mg/ml. In vitro assessment of effect of ginger was carried out after 24 and 48 h. For post-treatment evaluation, the viability of G. lamblia trophozoites was tested by their morphological criteria and dye staining (eosin stain 0.01%). Results The culture yielded a rich growth of G. lamblia trophozoites. Dead trophozoites stained pink with eosin and showed loss of morphological criteria. NTZ treatment significantly lowered the number of the parasites after 48 h (mean: 42.5±3.53/ml; P≤0.002), with a reduction rate of 92.93%, compared with PBS. Ginger treatment significantly lowered the number of the parasites after 48 h (mean: 55±7.07/ml, P≤0.004), with a reduction rate of 94.4%, compared with PBS. Conclusion The present study confirmed that ginger extract is equally active against G. lamblia as NTZ. More research studies are needed to highlight the physiological and molecular mechanisms of action of ginger and provide more scientific evidence of its effectiveness. Moreover, this simple G. lamblia axenic culture medium proved beneficial for evaluation of the susceptibility of isolates to antiparasitic drugs.

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Background Appendicitis is the most common acute surgical condition of the abdomen, and appendectomy constitutes one of the most common surgical operations worldwide. Gender, age, seasonal variation and leucocytic count have been investigated in many studies, however, causative parasitic agents of appendicitis are the most important. They differ from country to country. Objective The present study aimed to investigate parasitic infections as causes of appendicitis among patients attending Minia University Hospital, Minia Governorate, EL Minia, Egypt. Methodology This descriptive study was carried out during the period between October 2013 and March 2014. Among 100 patients treated by appendectomy with a prediagnosis of appendicitis, 55 were males and 45 were females. All patients with clinically prediagnosed appendicitis were subjected to an open appendectomy, in which a right Macberny incision was made, followed by delivery of the caecum, devascularisation of the appendix, base ligation and appendectomy. Removed appendices were preserved in 10% formalin, fixed, sectioned, stained with H & E and examined for histopathological changes and presence of parasites. The faecolith contents of the remaining portions of appendices were evacuated. A wet mount preparation from each specimen was subjected to light microscopic examination for detection of parasites. Results Parasitic infection was detected in nine appendectomy specimens. The presence of Enterobius vermicularis worms was confirmed in three cases by both histopathological and faecolith examinations. Eggs of Ascaris lumbricoides, Ancylostoma duodenale and Hymenolepis nana were detected in one case each by faecolith examination. Bilharzial granulomas were detected in three cases by histopathology. Interestingly, E. vermicularis and the eggs of A. lumbricoides, A. duodenale and H. nana were found to be associated with obstructive acute appendicitis, whereas bilharzial granulomas were observed in chronic appendicitis. Conclusion The study concluded that parasitic infections constitute only 9% of the surgically removed appendices. Schistosoma spp. and E. vermicularis were the most common parasitic recorded. The association of H. nana with acute appendicitis appears to be a novel finding. A combination of histopathology and faecolith examinations is necessary for detection of parasitic causes of appendicitis.

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Background Cestode tegument is the barrier that separates the parasite from the host, allowing it to develop and survive the hostile environment of the host. It is the only site for nutrient intake. Objective The present study was conducted to reveal the fine structural transformation of the tegument of Taenia pisiformis cysticerci (Cysticercus pisiformis) during development from egg to cysticercus stages. Materials and methods The present study records the development of C. pisiformis in experimentally infected domestic rabbits, with special emphasis on the ultrastructural variations within different stages of larval development using both scanning (SEM) and transmission (TEM) electron microscopes. Results Three to six days postinfection, the early developed scolex appeared as an invaginated thickening at the anterior end of the developed metacestode. The first development of the rostellar hooks and invagination canal was observed 1 week postinfection (PI), where the hooks appeared as minute conical bodies. Complete development of the invagination canal and hook crown was observed 2 weeks later, synchronizing with the onset of sucker differentiation. Fine structural transformation of the tegument included variations in the structure of microtriches (length, density, and shape); distal cytoplasm and parenchymal vesicles and inclusion bodies (size, shape, distribution, and electron density); and tegumental and parenchymal muscles (thickness, orientation, and distribution). Conclusion The tegument of different developmental stages of T. pisiformis cysticerci has the same basic pattern, with some variations in the subcellular structures, which supports the suggestion that T. pisiformis can be used as an experimental model in cysticerci research.

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Background Giardia lamblia trophozoites colonize in the upper small intestine resulting in diarrhea and various clinical manifestations, including abdominal pain, anorexia, and signs of malabsorption. A decrease in the level of trace elements might occur because of this absorption deficiency resulting from giardiasis. Experimentally, the excretory secretory product of G. lamblia trophozoites increased the level of reactive oxygen species in mice enterocytes. The levels of bilirubin, uric acid, and albumin are often used as major nonenzymatic oxidative biomarkers. Objective This study was designed to determine the effect of therapy by metronidazole (MTZ) and artemether (ART) on trophozoite and cyst forms in experimentally Giardia spp.-infected hamsters and to reveal the changes in iron (Fe), manganese (Mn), copper (Cu), and chromium (Cr) serum levels pretreatment and post-treatment. Another objective was to evaluate the impact of this therapy on serum levels of bilirubin, uric acid, and albumin as nonenzymatic oxidative stress biomarkers. Materials and methods Hamsters were divided into four groups: the control group I included two subgroups, Ia (noninfected, nontreated) and Ib (infected, nontreated); group II (infected and treated with MTZ); group III (infected and treated with ART); and group IV (infected and treated with combined therapy of MTZ+ART). Hamsters of all four groups were killed 5 weeks postinfection (PI) - that is, 2 weeks after treatment - to evaluate drug efficacy. Stool samples and duodenal contents were examined to count the number of G. lamblia cysts and trophozoites, respectively. Blood samples were also collected to estimate trace elements (Fe, Mn, Cu, and Cr) as well as nonenzymatic oxidative stress biomarkers (bilirubin, uric acid, and albumin). Results There was a significant reduction in trophozoite and cyst counts following treatment with ART alone (88 and 82.5%, respectively) as compared with the infected control group Ib. Treatment with MTZ alone and in combination with ART also yielded a very high percentage of reduction in both trophozoites (94.2 and 98.3%, respectively) and cysts counts (93.9 and 95.5%, respectively). The trace elements in serum of infected controls (Ib) displayed nonsignificant decrease in Fe and significant decrease in Mn levels as compared with their levels in noninfected hamsters of group Ia. Cu levels increased in the infected group and were still increased after treatment with either MTZ or ART but decreased to normal with the combined therapy. Cr levels showed no significant change in all groups. Uric acid increased in infected controls as compared with normal controls. Treatment with MTZ or ART alone decreased uric acid levels lower than normal, and the combination of both drugs normalized its levels. Evaluation of serum bilirubin levels in the infected group and in those treated by MTZ and ART alone did not show any statistically significant differences compared with the normal noninfected group. Treatment with the combined therapy yielded even slightly lower insignificant level. Albumin level also did not differ significantly except in the combined regimen where it was lower than the normal range. Conclusion The effect of giardiasis on the changes in the level of trace elements and nonenzymatic oxidative stress biomarkers is relevant in this study. The combined therapy produced significant parasite eradication and normalized the studied parameters with the exception of Mn and albumin levels, which were adversely affected and remained lower than normal. Further studies are needed to evaluate these data in undernourished and chronically infected hamsters.

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List of contents 1. Plasmodium spp. 1.1. Introduction 1.2. Historical background 1.3. Applications 2. Leishmania spp. 2.1. Introduction 2.2. Applications 3. Trypanosoma spp. 3.1. African trypanosomiasis 3.1.1. Applications 3.2. American trypanosomiasis 3.2.1. Introduction 3.2.2. Applications 4. Toxoplasma gondii 4.1. Applications 5. Cryptosporidium spp. 5.1. Applications 6. Other protozoa 6.1. Babesia spp. 6.2. Microsporidium spp. 6.3. Giardia lamblia 6.4. Eimeria spp. 6.5. Trichomonas vaginalis 6.6. Entamoeba histolytica 6.7. Free living amoeba 6.8. Cyclospora cayetanensis 6.9. Blastocystis spp. 6.10. Theileria spp. Concluding Remarks References Abbreviations ASS: African sleeping sickness; BiP: Binding protein; BS: Bloodstream forms; CL: Cutaneous leishmaniasis; COWP: Cryptosporidium oocyst wall protein; CTL: Cytotoxic T-lymphocyte; Cy: Cytosolic; ER: Endoplasmic reticulum; GA: Geldanamycin; GP60: Glycoprotein 60; HSP: Heat shock protein; ITS: Internal transcribed spacer; KMP-11: Kinetoplastid membrane protein-11 gene; MAb: Monoclonal antibody; MCL: Mucocutaneous leishmaniasis; MHC: Major histocompatibility complexe; Mit: Mitochondrial; NO: Nitric oxide; PS: Procyclic forms; PTEX: Plasmodium translocon of exported proteins; sHSP: small heat shock protein; SSU: Small subunit; TL: Tegumentary leishmaniasis; TLR: Toll like receptor; VL: Visceral leishmaniasis; VSG: Variant surface glycoprotein.

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Background Drug resistance to treatment of fascioliasis with triclabendazole (TCBZ) has emerged in Sohag Governorate, Egypt. Nitroxynil belongs to the halogenated phenol group of fasciolicides. It is highly active against adult liver flukes. A nitroxynil metabolite is produced in the liver parenchyma adding to its flukicidal activity and augmenting its efficacy against late immature flukes that migrate through the liver tissues. Treatment with nitroxynil may be an effective replacement for therapy with TCBZ in cases of resistance. Objective The aim of this study was to evaluate the efficacy of nitroxynil in the treatment of fascioliasis by assessing its effect on teguments and durability of adult Fasciola gigantica and Fasciola hepatica worms. Materials and methods Infected cows were selected on the basis of clinical signs, and infection was confirmed by detection of Fasciola eggs in their stools. Nitroxynil was administered as recommended in two doses 15 days apart, and the animals were slaughtered 15 days after treatment. Fasciola worms collected from the bile ducts were identified and prepared for electron microscopy. Tegument changes were examined with scanning electron microscopy. Results The removed adult flukes of both species were moving sluggishly and appeared pale with no evidence of gut content. Scanning electron microscopy examination of these flukes revealed evidence of swelling of the tegument that showed regional variation in its severity. Loss of spines was also observed. Conclusion The present study demonstrated the flukicidal properties of nitroxynil, proving that the tegument is an important target for its action. Disruption of the fluke's main line of defense allowed the drug access to other internal tissues, leading to more widespread damage. Nitroxynil may be successfully used for treatment in case of resistance to TCBZ.

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Background Pathogenicity of the protozoan parasite Blastocystis hominis is a subject of debate. It has been suggested that the pathogenic outcome may be linked to specific subtypes of Blastocystis spp. Studies on experimental infection in animals have reported varying degrees of illness depending on the used genotype. Objective This study was designed to identify a possible link between Blastocystis genotypes and gastrointestinal illness. In addition, the CD3 and CD20 local immune response to infection using symptomatic isolates was experimentally evaluated. Patients and methods Blastocystis- infected symptomatic (n = 51) and asymptomatic (n = 19) patients and irritable bowel syndrome patients (n = 32) were enrolled in the study, after exclusion of individuals who had other possible fecal pathogens. Restriction fragment length polymorphism was used for genotyping of isolates. Isolates from symptomatic cases were used for experimental infection, and immunohistochemical characterization of local CD3 and CD20 response was evaluated at two time intervals (groups A and B) after infection. Results Genotype 3 was the most common, being detected in 55.9% of all studied participants, and genotype 4 was the least common (9.8%). Symptomatic cases constituted 90% of genotype 1, 45.6% of genotype 3, 40% of genotype 4, and 20% of genotype 2. Genotype 2 was detected in 14.7% of all studied patients, with asymptomatic patients accounting for 60% of this isolate. Twenty-four isolates of genotype 3 occurred in 42.1% of irritable bowel syndrome patients. Rats euthanized after 7 (group A) and 14 days (group B) had higher CD3 and CD20 mean cell counts compared with control rats. The mean cell count of CD3 cells was statistically significantly higher in group A compared with group B, whereas CD20 cells in group B showed statistically significantly higher mean count compared with group A. Conclusion We suggest that both host and pathogen factors cooperate to express the pathogenic behavior of the parasite.

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Background Acanthamoeba spp. keratitis is a devastating disease that can potentially result in threatening the sight of the affected eye. Ineffective lens-disinfecting systems and contaminated contact lens storage cases have been recognized as the main risk factors for the infection. Objectives The present study aimed to evaluate the efficacy of nine different commercially available contact lens solutions in the Egyptian market against Acanthamoeba spp. trophozoites and 2-week-old cysts. Materials and methods Nine solutions were tested: eight multipurpose solutions (MPS) and one one-step hydrogen peroxide solution. Acanthamoeba spp. was isolated from a keratitic patient, cultivated on 1.5% non-nutrient agar (NNA), harvested, adjusted in two final concentrations of 5 × 10 ³ and 5 × 10 ⁵ trophozoites and cysts, and then incubated with the contact lens solution. The efficacy was tested at intervals of 2, 4, 6, 8, 10, and 24 h. Experiments were performed in triplicate. The viability was confirmed by reinoculation onto NNA seeded with Escherichia coli (NNA-E. coli). Results Most of the tested solutions showed significant trophzoiticidal activity, whereas all of the tested solutions failed to eliminate the 2-week-old cysts completely. The one-step hydrogen peroxide system failed neutralization within the minimum manufacturer's disinfecting time as it killed all the cysts of 5 × 10 ³ concentration after 10 h of soaking instead of 6 h; if used for this prolonged time, it could be hazardous to the users' eye. One of the MPS had high trophozoiticidal activity, but with an unknown recorded disinfectant, which could turn out to be of a toxic concentration or constitution. Conclusion Adjustment of the appropriate concentration of the disinfectant, the adequate exposure time, or even the development of new contact lens-disinfecting systems by manufacturers is needed to prevent Acanthamoeba spp. keratitis (AK). A MPS that fails to eradicate trophozoites or cysts within the minimum manufacturer's disinfecting time or one with an unknown recorded disinfectant should be avoided.

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The eicosanoid family includes prostanoids, leukotrienes, and other oxygenated derivatives. Prostanoids are a major class of the eicosanoid family derived from metabolism of arachidonic acid by the action of cyclooxygenase enzymes (COX). They are further subdivided into three main groups: prostaglandins (PGs), thromboxanes (TXs), and prostacyclins. PGs were first discovered as uterotonic substances in human seminal fluid in 1930. In the late 1950s to mid-1960s, their structures were studied and identified as being derived from unsaturated fatty acids. Prostanoids are produced by many cell types such as vascular endothelium, leukocytes, and the pathogens themselves. Prostanoid production is controlled by expression of different enzymes engaged in prostanoid biosynthesis, and by the distribution of different specific prostanoid synthases within those cells that determine their effect on the immune system. The production of prostanoids differs from one cell type to another; for example, dendritic cells predominately produce PG E ₂ (PGE ₂ ) and TXA ₂ , whereas mastocytes produce PGD ₂ . All inflammatory cells, including monocytes/macrophages, and neutrophils, are the main source of COX metabolites. Produced in response to various physiological and pathological stimuli, PGs are noted as key participants in autoimmune immunopathology, infectious diseases, and cancer. Other reports have shown that PGIs are formed by endothelial and smooth muscle cells, and TXAs are formed by platelets and lungs; PGI ₂ and some other PGs are produced by interactions between cells using enzymes in adjacent cells; for example, platelet-produced PGH ₂ is converted to PGI ₂ in the vascular epithelium. PGs secreted in the saliva of blood-sucking arthropods increase local blood flow and maintain the supply for feeding; they were also reported to increase immune suppression, allowing prolongation of attachment by ticks. Progressive studies demonstrated that, besides insects, pathogenic fungi, protozoa, and parasitic worms produce PGs. This review focuses on induced efforts to study prostanoids and their relation to different parasitic diseases. Abbreviations AA: Arachidonic acid; COXs: Cyclooxygenase enzymes; CyPG: Cyclopentanone; DC: Dendritic cell; GST: Glutathione-S-transferase; GA: Glycyrrhizic acid; MAP: Mitogen-activated protein; MIF: Macrophage migration inhibitory factor; NO: Nitric oxide; PBMC: Peripheral blood mononuclear cells; PG: Prostaglandin; PG12: Prostacyclin; PGE2: Prostaglandin E2; PL: Phospholipase; PPAR: Peroxisome proliferator-activated receptors; TGF: Transforming growth factor; TNF: Tumor necrosis factor; TP: Thromboxan receptor; TX: Thromboxane.

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Background The large-scale use of praziquantel might result in selection of drug-resistant parasites. Hence, there is an important need to develop new antischistosomal compounds. Objective This study aimed for assessment of antischistosomal properties of an antimalarial drug, mefloquine (MFQ), on juvenile and adult Schistosoma haematobium worms. Materials and methods Infected hamsters were divided into two main groups, I and II, each subdivided into (a) and (b) subgroups. Groups Ia and IIa received 200 mg/kg MFQ as single oral dose, 49 and 82 days postinfection, respectively. Groups Ib and IIb served as untreated controls, respectively. Ten days later, animals were killed. Parasitological assessment (worm burden, tissue egg load, and oogram pattern), histopathological examination, and scanning electron microscopy were performed to evaluate MFQ efficacy. Results MFQ treatment of the juvenile group Ia resulted in considerable worm burden reductions of 75.9, 69.6, and 88.6% for male, female, and coupled worms, respectively. In the treated adult group IIa, the corresponding results were 24.8 and 95% for male and coupled worms, respectively. Separate female worms were detected only in the treated groups. In group IIa treated animals, MFQ also had an observed but statistically insignificant effect on tissue egg load and oogram pattern. Schistosomal granuloma area, diameters, and numbers were insignificantly decreased. Tegumental changes of treated worms in the form of shrunken deformed tegument, loss or flattening of tubercles, furrows, and blebbing were observed. Conclusion Results concluded by this study elucidate promising MFQ antischistosomal efficacy on both juvenile and adult stages of S. haematobium with more evident effect on juvenile forms, which enforces the potential use of MFQ as an effective antischistosomal drug.

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Background Cryptosporidium spp. is a coccidian protozoan parasite that causes gastrointestinal disorders in human and animals. Several studies have demonstrated that the soil of public parks and schools presents an important source of infection which has a significant impact on public health. Children are the main group affected by accidentally ingesting contaminated soil. Aim of the work The aim of this study was to detect the presence of Cryptosporidium spp. oocysts in soil collected from primary schools and parks in Kermanshah city, west of Iran. Materials and methods The survey was conducted from August to December 2014 in Kermanshah city. Altogether 192 randomly selected soil samples were collected from 24 parks and 24 primary schools in six regions. The samples were screened for Cryptosporidium spp. oocysts using Sheather's flotation method and modified Ziehl-Neelsen staining. Results Out of 192 samples, 49 (25.5%) were found to contain Cryptosporidium spp. oocysts. Data analysis using χ² -test revealed that there was no significance among parks and primary schools in terms of the contamination rate (P = 0.24). Furthermore, there was no significant difference between the contamination rate and different regions of Kermanshah (P = 0.36). Regions 3 and 4 had the highest contamination rate (34.4%) and the lowest was for region 6 (15.6%). Conclusion Considering human infection with different Cryptosporidium spp. and the increase in numbers of immunocompromised patients, high contamination of soil with this parasite in Kermanshah stands as a serious problem. Consequently, health promotions, public education, improving sanitation conditions, especially for the underprivileged, are the keys to success in preventing the spread of Cryptosporidium spp. infection. In this regard, findings of this study can be used as a basis for preventive programs and development strategies targeting groups for the prevention of greater risk of cryptosporidiosis.

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Background The role of fish living freely in their natural habitats in the transmission of fish-borne trematodes is well recognized. Moreover, the role played by aquaculture fish has also gained great attention in the last few years. Objectives To investigate the rate, density, distribution of infection, and infectivity of heterophyid metacercariae in free living and farmed fish collected from El-Max Bay, a Mediterranean coastal bay in Egypt. The influence of freezing duration on the infectivity of the detected metacercariae was also evaluated. Materials and methods Tilapia nilotica and Mugil cephalus from both habitats were examined for encysted heterophyid metacercariae using a compression method. The density of infection was estimated by the number of metacercariae per gram of trunk tissue following artificial digestion. The distribution of infection was studied in snips taken from the head, gills, trunk, viscera, and tail. Infectivity of the collected metacercariae was tested in rats. The susceptibility of metacercariae to freezing was evaluated by assessment of their infectivity to rats after they were kept frozen at −15°C for 4, 7, and 14 days. Results Rates of infection with heterophyid metacercariae ranged from 11 to 23% in the different groups of fish. Free living fish had a significantly higher rate of infection and/or density as well as higher infectivity of metacercariae than farmed fish. Higher metacercarial density was observed in the trunk and viscera of the studied fish compared with the head, tail, and gills. Infectivity of the detected metacercariae decreased gradually with increasing duration of freezing. Conclusion Both free living and farmed fish can transmit Heterophyes parasites, the former being somewhat more important. The potential risk of human infection is considered to be high. Freezing for 2 weeks is an effective means of inactivating the parasite. Our results underscore the need to raise awareness among public health agencies, consumers, and aquaculture managers of the measures needed to reduce transmission of this intestinal fluke.

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Background Mirazid (MZD) was licensed in Egypt for treatment of schistosomiasis in the year 2002; the drug gained much attention experimentally and clinically, with conflicting views on its efficacy. Objective The study aimed to evaluate MZD anti-schistosomal activity in an animal model at a selected dose. Materials and methods Swiss albino mice (n=36) were infected with Schistosoma mansoni and divided into two equal groups of 18 mice each: group 1 was the nontreated infected control group given only the vehicle; gourp 2 was infected and treated with MZD at a dose of 500 mg/kg for 5 days per os 7 weeks postinfection. Efficacy of the drug was assessed parasitologically with fecal egg counts evaluated every other day until the animal was euthanized at 1, 2, and 4 weeks post-treatment (WPT); worm burden, tissue egg count and oogram pattern were studied at 1, 2, and 4 WPT. Results MZD reduced fecal egg counts in infected mice (69.6%) and reduced total worm load (71.9%) and tissue egg counts in the intestine and the liver (66 and 77.4%, respectively) at 4 WPT. The drug changed oogram pattern with progress of treatment. Conclusion MZD has moderate antischistosomal activity in animal models.

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Background Schistosomulum stage is believed to be the target of protective immunity. Over the past two decades, several investigators have demonstrated the antigenic communion between Schistosoma mansoni and Biomphalaria alexandrina. Objective The present study aimed to evaluate the effect of combining S. mansoni schistosomal lung antigen preparations and B. alexandrina antigen preparations for use as antischistosomal vaccination in murine models, and to compare their efficacy with and without the use of complete Freund’s adjuvant (CFA). Materials and methods Seventy laboratory-bred Swiss albino male mice were used in this study. They were classified into seven groups (10 mice each). Each mouse was sensitized with an initial subcutaneous injection of the extracted antigens. After 2 weeks, a second subcutaneous injection of the same antigen dose was given. Two weeks after the last dose of vaccination, all mice groups were infected with 100 S. mansoni cercariae subcutaneously. Mice were sacrificed by rapid decapitation 7 weeks post-infection for assessment of the inoculated antigens by parasitological (stool egg count, worm burden, tissue egg load, and oogram pattern) and histopathological (hepatic sections stained with hematoxylin and eosin for detection of granuloma number and diameter) studies. Results The data showed that vaccination with combined antigens (S. mansoni schistosomal lung antigen prepations + B. alexandrina antigen preparations with CFA) had the best protective effect. Conclusion The single antigen vaccination did not protect against infection by antigenically complexed S. mansoni. The cocktail vaccine apparently induced an agreeable immune response against many of the antigenic components. This new cocktail represents a promising approach toward the future development of vaccine strategy.

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Background Different diagnostic techniques have been used in the diagnosis of schistosomiasis. However, they are far from ideal regarding its early diagnosis. PCR techniques have been tried to improve the direct detection of schistosomiasis. Objective The aim of the present study was to evaluate the diagnostic performance of direct amplification of Schistosoma mansoni DNA in the early prepatent period in experimentally infected mice by PCR technique using unextracted DNA as PCR template compared with pre-extracted S. mansoni DNA samples. Materials and methods Mice were infected by 100±10 S. mansoni cercariae. Three mice were sacrificed every 3 or 4 days for 5 weeks. Whole blood samples were collected for direct amplification without prior extraction. Serum samples were pooled, and the extracted DNA was detected by using the KAPA blood PCR kit and conventional PCR methods. The diagnostic performance was compared between the two methods. Results The results showed that the diagnosis of S. mansoni utilizing pre-extracted DNA was superior to direct amplification of DNA, bypassing nucleic acid extraction which failed to detect S. mansoni DNA in any of the examined samples. Pre-extracted DNA was detected in all samples from the second day after infection by using the two PCR techniques. Conclusion These results indicate that S. mansoni infection cannot be efficiently detected directly by using the PCR technique without pre-extraction of DNA from whole blood samples using the KAPA blood PCR kit.

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Helminthic infections cause severe diseases (helminthiases) associated with significant morbidity and mortality worldwide. Many individuals are not aware of the risks and complications of helminthiases in reproductive health; hence, the infections are often neglected, leading to severe outcomes. These infections are often misdiagnosed and result in miscarriages, infertility, ectopic pregnancy, and increased risk of other conditions. Infected women of reproductive age often pass infections to their fetus during pregnancy and childbirth, which consequently affects their growth and development. In addition, the resultant morbidity affects the economic productivity and quality of life of individuals and communities. For the present review, both electronic (PubMed, Medline, EBSCO host, Science Direct) and manual literature were searched for relevant articles. The review highlights emerging issues on clinical manifestations, risks, and complications. Besides impairment of reproductive health in developing countries, helminthiases increase the transmission of viral, fungal, and bacterial infections, and promote stigma and sex inequality. The clinical and social impact of these neglected, forgotten infections largely considered to be of low public health importance is discussed. Because of the immense and increasing impact on global health and development, health professionals are encouraged to confer high priority to helminthiases.

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All forms of infectious microbes, such as viruses, bacteria and parasites, can induce an inflammatory immune response which, under toxic environmental conditions, can cause cancer cells to grow. Some parasitic species were documented to have carcinogenic activity, namely; Schistosoma hematobium associated with squamous cell carcinoma of the urinary bladder and the liver flukes Opisthorchis and Chlonorchis associated with cholangiocarcinoma of the bile duct. This review aimed to examine the association of selected protozoa in human cancer. CONTENTS Introduction Cryptosporidium parvum Toxoplasma gondii Trichomonas vaginalis Blastocystis hominis Plasmodium falciparum Concluding remarks References Abbreviations: Apc: expression of tumor suppressor; ASC-H: atypical high grade squamous cells; ASCUS: atypical squamous cells of undetermined significance; BCL2: B cell lymphoma; β-catenin: the coordinator of cell-cell adhesion and gene transcription; c-Myc: transcription factor; CTL: cytotoxic T lymphocytes; eBL: endemic Burkitt lymphoma; EBV: Epstein Barr virus; Fas: apoptosis stimulating fragment; HCT8: human ileocaecal carcinoma; HCT116: human colorectal carcinoma cells; IFN-g: interferon gamma; miRNAome: 18-23 nucleotide non-coding RNAs that regulate gene expression in a sequence specific manner; miRNAs: micro RNAs; NF-Kb: nuclear factor kappa light-chain; SCID: severe combined immunodeficient; SIL-H: high-grade squamous intraepithelial lesions; TLR4: toll like receptor 4; TNFα: tumor necrosis alpha; Wnt: a group of signal transduction pathways made of proteins that pass signals from outside of a cell through cell surface receptors to the inside of the cell; ZO-1: a tight junction protein encoded by the TJP1 gene in humans

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