HISTOPATHOLOGICAL AND IMMUNOHISTOCHEMICAL STUDIES IN EXPERIMENTAL HETEROPHYIASIS AND THE ROLE OF PRAZIQUANTEL AND AMINOGUANIDINE.

Histopathological diagnosis was used to understand the pathological events associated with Heterophyes heterophyes (H. heterophyes) infection. CD3 and CD79α antibodies had been used as markers for both T and. B lymphocytes respectively. Immunohistochemical techniques had several advantages as remarkable sensitivity and specificity. This study aims to evaluate the roles-of praziquantel (PZQ) and aminoguanidine (AG) treatment in H heterophyes infected dogs pathologically and immunohisto-chemically. Study design included experimental infection of dogs with encysted metacercariae of H heterophyes followed by treatment with PZQ and AG. Tissue samples were taken from small intestinal, liver, heart and lung of all groups for histopathological and immunohistochemical studies. Pathological changes were detected in infected tissues by histopathological examination. There was different degree of CD79α+B lymphocytic & CD3+T lymphocytic infiltration detected in immuno-histochemical stained tissues. PZQ caused improvement of pathological changes in the small intestine. However the cellular inflammatory infiltration increased. There was reduction in inflammatory infiltration after intake of AG. Both PZQ and AG improved the pathological changes in the.liver, heart and lung, while the cellular inflammatory infiltration increased after PZQ and reduced by AG. Moreover in the lung AG improves pulmonary congestion and alveolar wall thickness.

[Effect of some pharmacological substances on the motility of the Cryptocotyle lingua cercaria (Heterophyidae)].

The effect of some biologically active substances (acetylcholine, serotonin, octopamine, sodium nitroprussid and FMRF-amide) on the motility of the Cryptocotyle lingua cercariae was studied. Solutions of FMRF-amide, octopamine, and sodium nitroprussid have no statistically significant influence on the motility of C. lingua. Acetylcholine and serotonin in solutions affected the motility through the prolongation of the active phase of swimming. Further research is required to elucidate the mechanisms underlying the cercarial motility.

Mirazid in treatment of three zoonotic trematodes in Beni-Sweif and Dakhalia Governorates.

A total of 60 patients with schistosomiasis (40), fascialiosis (15) and heterophyiasis (5) were selected Beni-Sweif and Mansoura Districts and subjected to history taking, clinical examination, Kato thick smear, sedimentation and hatching test (for schistosomiasis cases) at the beginning of the study, 2 & 3 months after treatment with Oleo-resin of Myrrh (Mirazid) in a dose of 10 mg/kg/day for 6 consecutive days an hour before breakfast. The results showed a significant improvement in symptoms with minimal negligible or no side effects. The cure rates, 2 & 3 months after treatment were 80.7%% & 11.8%% for schistosomiasis, 93.3% & 6.6% for fascioliasis, and 100% for heterophyiasis. The clinical picture of schistosomiasis before treatments were easy fatigability, anorexia, nausea, vomiting, epigastria pain, abdominal distention, right upper guardant pain, colicky abdominal pain, left upper and/or lower guardant pain, abdominal rumbling, dysentery, diarrhea, rectal bleeding, constipation, and alternating bowel habit. Those of fascioliasis were abdominal distention, dripping of saliva, right upper guardant, colicky abdominal pain, weight loss, easy fatigability, intermittent jaundice, anorexia, nausea, vomiting, epigastria, left upper and/or lower quadrant pain, right layer quadrant pain, loin pain, abdominal rumbling, diarrhea, constipation, and alternating bowel habit. The safety and efficacy of C. molmol extract in treating heterophyiasis (100%), fascioliasis (100%) and schistosomiasis (92.5%) were documented.

Mirazid (Commiphora molmol) in treatment of human heterophyiasis.

A total of 3278 patients attended Mansoura University Hospitals' Clinics with gastro-intestinal troubles suggesting parasitosis were examined by direct smear and by Kato-Katz methods for parasites especially Heterophyes heterophyes. Fifty clinically and parasitologically proved pure heterophyiasis patients were given Mirazid as two capsules for 9 successive days on an empty stomach an hour before breakfast. All the cases were subjected to history taking and clinical examination before treatment and were followed-up for four weeks post-treatment. There was an overt clinical and parasitological improvement. A total of 47 out of 50 (94%) were cured. Another course was given to the three patients who were still positive, but only two of them were cured (66.7%). The overall cure rate was 49/50 (98%) and none had any side effect. The history and treatment of this zoonotic parasite was critically discussed.

Effect of niclosamide on the tegumental surface of Haplorchis taichui using scanning electron microscopy.

The effect of niclosamide on the tegument of adult Haplorchis taichui (Trematoda: Heterophyidae) exposed in vitro was observed by scanning electron microscope. Adult worms were incubated in Tyrode's solution containing 0.01, 0.1, 1.0, and 10 microg ml(-1) of niclosamide for 30 min, 1, 6, 12 and 24 h. Control groups were incubated in Tyrode's solution without niclosamide and worms remained active until 24 h. In 0.01 microg ml(-1) of niclosamide, worms showed slightly active movements up to 1 h after incubation, while in 0.1 microg ml(-1) solution a few worms showed only slightly active movements after 30 min. Tegumental changes were determined by scanning electron microscopy. Swelling and blebbing of the tegument were observed on both ventral and dorsal sides. After longer periods, extensive swelling and blebbing of the tegument became more severe and there was a loss of the apical plasma membrane in some regions. Empty spine sockets occurred, and small perforations penetrated the basal lamina, followed by some lesions. Destruction of both surfaces was more pronounced on the posterior compared with the anterior regions.

Effect of Mirazid (Commiphora molmol) on experimental heterophyidiasis.

Mirazid (MZ), an oleo-resin extract derived from Myrrh was reported in several experimental and clinical trails to be safe and effective against other trematodes like schistosomiasis and fascioliasis. This experimental work aimed at investigating the possible efficacy of MZ against heterophyids (Pygidiopsis genata), using praziquantel as a therapeutic control. Results showed that MZ in emulsion form is a promising drug for the treatment of heterophyidiasis, as proved by significant reduction of worm count, overt surface tegumental changes like deformity and erosion of tegumental spines observed by scanning electron microscope (SEM). The effective dose regimen was 500 mg/kg/d for 3 successive days, produced 100% reduction in worm load. The proved efficacy of the drug, together with reported low toxicity, relative to praziquantel, favours its use as a natural new alternative therapy for the treatment of human heterophyidiasis.

In vitro effects of aqueous extract from Artocarpus takoocha Roxb on tegumental surface of Haplorchis taichui.

The tegumental surface of the adult intestinal fluke, Haplorchis taichui, after in vitro incubation in Tyrode's solution containing 25, 50, 75 and 100% of aqueous extract of Artocarpus takoocha for 1, 6, 12 and 24 hours, was monitored by Scanning Electron Microscopy (SEM). The effect on worm motility was studied in contemporizing period. The adult worms stopped their motility immediately after being incubated with 25, 50, 75 and 100% of aqueous extract of A. takoocha. Observed under a light microscope, most worms showed bubbling from the oral sucker, ventral sucker and excretory pore. After exposure to the solution, SEM observation showed large blebs protruding from the oral sucker, ventral sucker and excretory pore. The surface damage was composed of numerous small blebs, followed later by the disruption of tegument. The severity of damage increased due to the increasing of aqueous extract of A. takoocha and incubation periods.

A focus of human infection by Haplorchis taichui (Trematoda: Heterophyidae) in the southern Philippines.

We report an exceptionally high rate of infection by Haplorchis taichui (Nishigori, 1924) in human populations on Mindanao Island, southern Philippines. This intestinal fluke is seldom encountered, and this is the first report of high prevalence of infection (36%) in humans by H. taichui in the Philippines. The likely source of haplorchine infection has been linked to consumption of raw or undercooked freshwater fish containing infective metacercariae. The most common clinical symptoms appeared as upper abdominal discomfort or pain and borborygmi. Praziquantel (75 mg/kg divided in 3 doses in 1 day) was a well-tolerated and effective treatment for infection by H. taichui.

Motility of minute intestinal fluke, Haplorchinae spp, metacercariae in fish dishes prepared by different uncooked methods.

CONTEXT: Fish-borne trematode is a worldwide problem, with the number of people infected by liver flukes alone estimated at 21 million. In addition to the major liver flukes, Opisthorchis viverrini and Clonorchis sinensis, several types of intestinal flukes also use cyprinoid fish as the intermediate host. Traditional ingestion of undercooked and uncooked fish preparations is a major factor in pathogen acquisition. OBJECTIVE: To examine the motility of Haplorchinae spp metacercariae in matched minnows using a number of preparation methods that mimic traditional practices. DESIGN: Several freshly killed freshwater fish, Cyclocheilichthys armatus, were purchased from the local market and sent to the authors' laboratory to be examined under a stereoscopic microscope for active Haplorchinae spp metacercariae. A total of 10 fish were infected with many active metacercariae and used in the preparation of uncooked fish dishes. Five different raw fish dishes that mimic traditional meals (2 fishes/dish) were prepared using the following methods: 1) left to dry at room temperature; 2) frozen at -20 Celsius; 3) refrigerated at 4 Celsius; 4) marinated in saline (5% sodium chloride solution); and 5) marinated in 5% acetic acid solution to mimic traditional vinegar. The motility of the metacercariae in each of these dishes was examined under a stereoscopic microscope. Motility was estimated as the level of activity or degeneration of the metacercariae at the start of the experiment and then every 30 minutes until all the parasites appeared degenerate (and therefore, presumably not viable). RESULTS: Degeneration of the parasites was slowed by cooling: degeneration of all metacercariae took approximately 5 hours in the refrigerated or frozen fish, compared with 3 hours in all other dishes left at room temperature. CONCLUSION: The study substantiates the epidemiologic data demonstrating transmission of these types of pathogens despite freezing, pickling, and salting. Although the tradition of eating uncooked fish is deeply rooted in Thailand, constant efforts need to be made to discourage this practice.

Prevalence of Opisthorchis viverrini infection among villagers harboring Opisthorchis-like eggs.

The precise occurrence of Opisthochis viverrini infection in humans, who were positive for Opisthorchis-like eggs in a stool examination, was determined using the potassium permanganate staining method. In the 68 specimens examined, there were more individual O. viverrini eggs (38.24%) than singular Haplorchis taichui eggs (29.41%). One-fourth of the total specimens contained a mixed infection of O. viverrini and H. taichi eggs. The median ratio of O. viverrini: H. taichui eggs in mixed infection cases was 2.29 (min = 1, max = 17.5). It is suggested that chemotherapy with praziquentel treatment should be given to patients who are positive for O. viverrini-like eggs.

Heterophyids: experimental chemotherapy and immunotherapy.

Heavy infections with the tiny flukes heterophyids can cause intestinal pain and mucous diarrhea, thus the study of praziquantel (Pzq) and the new drug cyclosporin A (CsA) as antiparasitic drugs were undertaken in this work, as well as the effect of matecercarial and adult antigens as immunizing agents. To assess the result of our work, the number and length of the recovered heterophyids were studied. Description of the surface by SEM was carried out for the groups: treated by cyclosporin A and immunized by adult heterophyid antigen (third fraction) which gave the highest percentage reduction.

Effects of praziquantel on human intestinal flukes (Fasciolopsis buski and Heterophyes heterophyes).

Human intestinal flukes (Fasciolopsis buski and Heterophyes heterophyes) were treated with praziquantel in vivo or in vitro and then studied by transmission (TEM) and scanning (SEM) electron microscopy. F. buski worms recovered from patients, which had been cured by oral treatment of 1 X 15, 1 X 25 or 1 X 40 mg praziquantel/kg body weight, showed typical contraction and alterations together with vacuolization and bleb formation of their tegument. H. heterophyes worms recovered from an experimentally infected dog were incubated in media containing 1 microgram praziquantel/ml for 5-60 min. Their tegument showed lesions the extent and duration of which increased with exposure time, finally leading to death. The damage observed in vitro was very similar to that found in F. buski recovered from cured patients. The cure rate was very high when using 1 X 15 mg praziquantel/kg.