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1.
Korean J Parasitol ; 58(4): 373-386, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32871631

RESUMO

Fish-borne heterophyid trematodes are known to have a zoonotic potential, since at least 30 species are able to infect humans worldwide, with a global infection of around 7 million people. In this paper, a 'state-of-the-art' review of the South American heterophyid species is provided, including classical and molecular taxonomy, parasite ecology, host-parasite interaction studies and a list of species and their hosts. There is still a lack of information on human infections in South America with undetected or unreported infections probably due to the information shortage and little attention by physicians to these small intestinal flukes. Molecular tools for specific diagnoses of South American heterophyid species are still to be defined. Additional new sequences of Pygidiopsis macrostomum, Ascocotyle pindoramensis and Ascocotyle longa from Brazil are also provided.


Assuntos
Heterophyidae , Animais , Cianobactérias , DNA de Helmintos/genética , Peixes/parasitologia , Heterophyidae/classificação , Heterophyidae/genética , Heterophyidae/patogenicidade , Interações Hospedeiro-Parasita , Humanos , Análise de Sequência de DNA , América do Sul , Infecções por Trematódeos/parasitologia
2.
Parasit Vectors ; 6: 92, 2013 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-23574763

RESUMO

BACKGROUND: Melanoides tuberculatus (Müller, 1774) (Thiaridae), an introduced gastropod mollusc with a wide geographical distribution in the Neotropics, is the intermediate host of the trematode Centrocestus formosanus (Nishigori, 1924) (Heterophyidae). This parasite is considered to be pathogenic to humans. The aim of the present work was to evaluate the locomotory activity of uninfected M. tuberculatus compared with those naturally infected with C. formosanus. FINDINGS: The locomotory activity of each mollusc was recorded using an image analysis biomonitoring system, Videomex-V, to evaluate and quantify the parameters of 'Stereotypic' and 'Resting time'. The Generalized Estimating Equation analysis of locomotory activity of M. tuberculatus infected with C. formosanus revealed significant differences compared with uninfected molluscs for the parameters 'Stereotypic time' and 'Resting time' with a reduction of movement. The variations in the values of the monitoring intervals recorded showed a significant difference for the infected molluscs in the case of Stereotypic time, with an irregular locomotory activity pattern, as compared to that of uninfected molluscs. The analysis of the standard length of all molluscs did not exhibit any correlation with locomotory activity, showing that C. formosanus is able to alter the locomotory activity of its snail host regardless of the standard length. CONCLUSIONS: The trematode C. formosanus affects the locomotory activity of the mollusc M. tuberculatus by reducing its movement and causing it to exhibit an irregular pattern of activity, both of which are independent of the snail's standard length.


Assuntos
Heterophyidae/patogenicidade , Moluscos/fisiologia , Moluscos/parasitologia , Animais , Bioensaio/métodos , Processamento de Imagem Assistida por Computador/métodos , Locomoção , Infecções por Trematódeos/parasitologia , Infecções por Trematódeos/patologia
3.
Parasitol Res ; 112(4): 1647-53, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23388732

RESUMO

A parasitological survey for Metagonimus yokogawai metacercariae was carried out by examining a total of 321 freshwater fish comprising of 7 species. Of the 321 fish samples examined, 182 (56.7%) were found to be infected with M. yokogawai metacercariae. The prevalence of M. yokogawai metacercariae in Opsariichthys pachycephalus was 93.4% (86/92), Zacco platypus 75.0% (30/40), Distoechodon turmirostris 61.3% (38/62), Varicorhinus barbatulus 56.5% (13/23), Hemibarbus labeo 33.3% (1/3), Acrossocheilus formosanus 15.9% (14/88), and 0% in Sinibrama macrops (0/13), respectively. This is the first record of M. yokogawai infection in Z. platypus, D. turmirostris, V. barbatulus, and H. labeo in Taiwan. The major site of predilection of the metacercariae in the fishes was in the scale, but some metacercariae were also observed in the flesh and fins. The M. yokogawai metacercariae were orally inoculated into mice, rat, gerbil, and golden hamster to study their infectivity and also to obtain the adult worms for taxonomic study. Worm recovery in hamsters was 75.3%, in mice was 70.0%, in rats was 23.3%, and in gerbils was 6.0%, respectively. Moreover, larger worms were recovered from the golden hamster. Golden hamster was thus found to be the most susceptible experimental rodent host for the infectivity study of Metagonimus. Besides M. yokogawai, metacercariae of Centrocestus formosanus was also observed in the fishes examined.


Assuntos
Doenças dos Peixes/epidemiologia , Peixes/parasitologia , Heterophyidae/crescimento & desenvolvimento , Heterophyidae/isolamento & purificação , Roedores/parasitologia , Infecções por Trematódeos/veterinária , Experimentação Animal , Animais , Cricetinae , Doenças dos Peixes/parasitologia , Gerbillinae , Heterophyidae/patogenicidade , Camundongos , Prevalência , Ratos , Taiwan , Infecções por Trematódeos/epidemiologia , Infecções por Trematódeos/parasitologia
4.
Parasit Vectors ; 6: 4, 2013 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-23289937

RESUMO

BACKGROUND: Infections with fish-borne zoonotic trematodes (FZT) including the minute intestinal fluke, Haplorchis pumilio, are highly prevalent in Southeast Asia. However, little is known about the infection dynamics and clinical symptoms in the final hosts which include a range of animal species and man. We aimed to generate such information using an experimental model with H. pumilio in foxes. METHOD: Eight commercially bred foxes were each orally infected with 2000 H. pumilio metacercariae. Another three foxes served as uninfected controls. Faecal examination for eggs was performed twice weekly. The body weight was measured, standard haematological and biochemical analysis were performed regularly. All foxes were euthanized at day 56 post infection (p.i.). Adult worms were quantified and location in the small intestine noted. RESULTS: Anorexia was observed in all infected foxes starting day 12 p.i. and lasting for approximately a week. A weight loss was noticed in the infected group in weeks 3-6 p.i. Five of eight infected foxes excreted H. pumilio eggs day 9 p.i. onwards, the remaining three started on day 13 p.i. Mean (± SD) faecal egg counts showed an initial peak at day 16-20 with a maximum of 1443 ± 1176 eggs per gram of faeces (epg), where after a stable egg output around 4-500 epg was seen. Worm burdens ranged between 116-2070 adult flukes with a mean (± SD) worm recovery of 948 ± 666. The majority of worms were found in the lower part of the jejunum. Total white blood cell and lymphocyte counts were significant lower in the infected group from first week p.i. onwards and throughout the study period. A significantly lower level of eosinophils was found in week 2 p.i. and transient anaemia was seen in week 2 and 4 p.i. CONCLUSION: This study showed a short prepatency period, an initial peak in egg excretion, establishment of infection in all animals with predilection site in the lower jejunum and a marked but transient clinical effect of the infection. The findings on egg output and prepatency should be taken into consideration when control programs targeting dogs and other reservoir hosts are to be established.


Assuntos
Raposas/parasitologia , Heterophyidae/isolamento & purificação , Infecções por Trematódeos/veterinária , Anemia , Animais , Anorexia , Peso Corporal , Fezes/parasitologia , Feminino , Fertilidade , Doenças dos Peixes/parasitologia , Carpa Dourada/parasitologia , Heterophyidae/patogenicidade , Heterophyidae/fisiologia , Interações Hospedeiro-Parasita , Intestino Delgado/parasitologia , Intestino Delgado/patologia , Contagem de Linfócitos , Metacercárias , Contagem de Ovos de Parasitas/veterinária , Dinâmica Populacional , Fatores de Tempo , Infecções por Trematódeos/parasitologia , Infecções por Trematódeos/patologia
5.
Parasitol Res ; 110(3): 1209-12, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21845407

RESUMO

As the second intermediate host, the perch Lateolabrax japonicus provides metacercariae of Heterophyopsis continua to man. Fry of the perch arrive at and grow to mid-sized fish in the brackish water of Jinju Bay, South Korea. The H. continua metacercariae occur in perch as small and mid-sized forms in July and grow to the large form by August. The size distribution of metacercariae shifts dominantly to the large form in September and then remains as it was. Adult H. continua recovery was high from experimental chicks infected with the medium and large metacercariae collected in September and reduced to half from the chicks infected with those of October. Collectively, the H. continua metacercariae grew to the large form in about 20 days and achieved infectivity to chicks after 2 months in the perches.


Assuntos
Galinhas/parasitologia , Heterophyidae/fisiologia , Heterophyidae/patogenicidade , Interações Hospedeiro-Parasita , Metacercárias/fisiologia , Percas/parasitologia , Estações do Ano , Infecções por Trematódeos/veterinária , Animais , Metacercárias/patogenicidade , Doenças das Aves Domésticas/parasitologia , Infecções por Trematódeos/parasitologia
6.
Parasitol Res ; 110(2): 679-87, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21779862

RESUMO

Heterophyiasis is an important food-borne parasitic zoonosis in Egypt, among the inhabitants living around brackish-water lakes especially fishermen, and it is a common human parasite in the Nile Delta. The experiment was done on two laboratory animals (rats and dogs), and the time of sample collection was done periodically at 6, 9, 15, 21, and 28 days post-infection to evaluate different tests required. Whole blood was collected with heparin or ethylenediamine tetra-acetic acid as anticoagulant to help in the hematological studies such as red blood cells count (RBCs), white blood cells count, packed cell volume (PCV), and hemoglobin (Hb). Only marked increase in the total leuckocytic count was recorded while RBCs, PCV, and Hb were decreased in most of the results obtained. Total protein and globulin decreased while albumin and A/G ratio increased. Liver enzymes showing marked increase in aspartate aminotransferase and increase in alanine aminotransferase in dogs and rats denoting that liver has a role in the response to that infection. Kidney-function tests, urea, and creatinine showed slight increase at 6 days post-infection (d.p.i.). After preparation of different Ag (antigen) from different collected helminthes, the protein content of each was determined. The sera of infected animals were collected to find antibodies in their blood against the parasite using enzyme-linked immunosorbent assay and using crude heterophyid antigen collected from their intestines after scarification. The worms washed, homogenized, and then centrifuged to collect supernatant fluid as antigens. The results indicated that antibody starts to appear at 9 d.p.i. and increases till 21 and 28 d.p.i. and detection depends on antigen concentration.


Assuntos
Heterophyidae/patogenicidade , Infecções por Trematódeos/patologia , Animais , Animais de Laboratório , Anticorpos Anti-Helmínticos/sangue , Células Sanguíneas/fisiologia , Análise Química do Sangue , Técnicas de Laboratório Clínico/métodos , Modelos Animais de Doenças , Cães , Egito , Ensaio de Imunoadsorção Enzimática/métodos , Testes de Função Renal , Testes de Função Hepática , Ratos , Infecções por Trematódeos/imunologia
7.
Parasitol Int ; 60(4): 503-6, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21946336

RESUMO

Six species of heterophyid intestinal flukes (HIFs) constitute the major endemic zoonotic fish-borne pathogens in Asia: Haplorchis taichui, H. pumilio, H. yokogawai, Procerovum varium, Stellantchasmus falcatus, and Centrocestus formosanus. Several different species of these parasites are often found co-infecting the same second intermediate fish host. Because of their morphological similarities, differentiating between species of HIF metacercariae is difficult, time-consuming, and frequently results in misidentification. In this study, we aimed to develop an efficient and accurate method of identifying metacercariae of these 6 HIFs. Metacercariae were roughly grouped together, based on morphological characteristics seen under a stereomicroscope. Then, PCR-restriction fragment length polymorphism (PCR-RFLP) was used to identify the exact species of each metacercaria, using the 28S ribosomal RNA gene as the genetic marker and MboII as the restriction enzyme. Using a combination of morphological and molecular methods eliminates the need for DNA sequencing and infecting animal subjects to obtain adult worms, increases accuracy, and decreases the need for laborious morphological identification. Because the method is simple, rapid, and relatively cheap compared with PCR-sequencing, it may be an effective tool for epidemiological studies of HIFs in endemic areas.


Assuntos
Doenças dos Peixes/diagnóstico , Heterophyidae/genética , Intestinos/parasitologia , Metacercárias/genética , Polimorfismo de Fragmento de Restrição , Infecções por Trematódeos/diagnóstico , Infecções por Trematódeos/veterinária , Animais , Ásia/epidemiologia , Desoxirribonucleases de Sítio Específico do Tipo II/genética , Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/parasitologia , Peixes , Água Doce/parasitologia , Heterophyidae/classificação , Heterophyidae/isolamento & purificação , Heterophyidae/patogenicidade , Humanos , Metacercárias/classificação , Metacercárias/isolamento & purificação , Metacercárias/patogenicidade , Microscopia , Reação em Cadeia da Polimerase/métodos , RNA Ribossômico 28S/análise , RNA Ribossômico 28S/genética , Infecções por Trematódeos/epidemiologia , Infecções por Trematódeos/parasitologia
8.
Adv Parasitol ; 72: 305-50, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20624536

RESUMO

The food-borne trematodiases are an important group of neglected tropical diseases (NTDs). Over 40 million people are infected with food-borne trematodes and 750 million (>10% of the world's population) are at risk of these NTDs. Here, we review the life cycles, epidemiology, clinical manifestations, pathology and pathogenesis, diagnosis, treatment, and prevention and control of the major food-borne trematodiases in Southeast Asia. We focus particularly on opisthorchiasis caused by Opisthorchis viverrini and clonorchiasis caused by Clonorchis sinensis, which people contract by ingestion of metacercariae in flesh of raw or undercooked freshwater fishes, on fascioliasis caused by Fasciola species, where infection arises from ingestion of metacercariae on water plants such as watercress, and on Paragonimus species, the lung flukes, which use freshwater crabs and other crustaceans as intermediate hosts. We also include information on the intestinal flukes Fasciolopsis buski, the echinostomes and the so-called 'minute intestinal flukes' of the family Heterophyidae. Ecological information, placing emphasis on reservoir hosts, intermediate snail hosts and secondary hosts where applicable, is also reviewed and research needs are highlighted.


Assuntos
Controle de Doenças Transmissíveis/métodos , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/patologia , Infecções por Trematódeos/epidemiologia , Infecções por Trematódeos/patologia , Animais , Ásia Sudeste/epidemiologia , Clonorchis sinensis/isolamento & purificação , Clonorchis sinensis/patogenicidade , Fasciola/isolamento & purificação , Fasciola/patogenicidade , Fasciolidae/isolamento & purificação , Fasciolidae/patogenicidade , Doenças Transmitidas por Alimentos/diagnóstico , Doenças Transmitidas por Alimentos/tratamento farmacológico , Heterophyidae/isolamento & purificação , Heterophyidae/patogenicidade , Humanos , Opisthorchis/isolamento & purificação , Opisthorchis/patogenicidade , Paragonimus/isolamento & purificação , Paragonimus/patogenicidade , Infecções por Trematódeos/diagnóstico , Infecções por Trematódeos/tratamento farmacológico
9.
Vet Parasitol ; 168(1-2): 45-50, 2010 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-19897304

RESUMO

Information concerning whether fowl such as duck is a suitable reservoir host of Metagonimus yokogawai is largely unclear to date. In the present study, the growth and development of M. yokogawai metacercaria (Mc) in domestic duck (Cairina moschata) was determined by worm recovery rate (WRR) and morphological changes e.g., the size of fluke's body as well as their internal organs was assessed by using Semichon's acetocarmine staining. Each duck was orally inoculated with 50 Mcs of M. yokogawai and infected ducks were deeply anesthetized with ether and killed at 1, 2, 3, 4, 5, 6, 7, and 14 days post-infection (DPI). On each date, two infected ducks were killed and the small intestines of each duck were separated into four parts then they were opened longitudinally to harvest the flukes. Results revealed that WRR of M. yokogawai from inoculated ducks increased during early infection with a peak as seen at 4 DPI (28.5+/-6.9%); thereafter it gradually decreased and a drastic decline was observed in 14 DPI (2.0+/-1.1%) in the trial. The preference sites for M. yokogawai were low portions of the small intestine; nevertheless the size of fluke's body and organs developed increasingly with time and they maturated to produce ova from 4 DPI onward in the trial. However, present results indicated that ducks, based on the findings of this study, are not suitable hosts for establishment of M. yokogawai infection because most flukes were expelled from duck's intestine within 14 days. Nevertheless, it was proposed that ducks might play a certain role in transmitting M. yokogawai when they deposited the ova via feces into marsh where snails and fish were abundant since they could presumably establish transient and possibly patent infections with this parasite.


Assuntos
Patos , Heterophyidae/crescimento & desenvolvimento , Heterophyidae/patogenicidade , Doenças das Aves Domésticas/parasitologia , Infecções por Trematódeos/veterinária , Animais , Fezes/parasitologia , Intestino Delgado/parasitologia , Fatores de Tempo , Infecções por Trematódeos/parasitologia
10.
J Parasitol ; 95(3): 629-33, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19642804

RESUMO

Recent studies in Vietnam and other Asian countries have shown that fish-borne zoonotic intestinal trematodes (FZT) occur very frequently in humans. The dominant intestinal FZT in Vietnamese fish are species of Haplorchis, in particular H. pumilio. However, basic studies on the biology and pathology of adult H. pumilio are difficult because of the lack of a standardized experimental animal model. The objective of this study was to establish and optimize such an animal-infection model for H. pumilio. Using metacercariae isolated from naturally infected fish, experiments were conducted to identify a suitable experimental animal host species, as well as the optimum metacercariae infection dose, and to determine the post-infection interval for patency. In a series of experiments, mice (Mus musculus) and chickens (Gallus gallus dom.) were infected with different numbers of metacercariae, and worm recoveries were made at varying intervals post-infection (PI). Based on the mean number of adult flukes recovered/number of metacercariae inoculated and the percent of hosts infected, mice were significantly more susceptible to infection than were chickens. The proportion of metacercariae developing to the adult stage increased with dose size. The peak worm recovery (geometric mean) was found to be day 7, although not all recovered flukes were gravid until day 9 PI. These results describe a mouse infection model with good predictability for intestinal flukes, such as H. pumilio, results which could facilitate investigations on important biological and pathological aspects of intestinal fluke infections.


Assuntos
Modelos Animais de Doenças , Suscetibilidade a Doenças , Doenças dos Peixes/parasitologia , Heterophyidae/isolamento & purificação , Infecções por Trematódeos/parasitologia , Análise de Variância , Animais , Carpas , Galinhas , Doenças dos Peixes/transmissão , Heterophyidae/imunologia , Heterophyidae/patogenicidade , Interações Hospedeiro-Parasita , Intestino Delgado/parasitologia , Camundongos , Fatores de Tempo , Infecções por Trematódeos/imunologia , Infecções por Trematódeos/transmissão , Zoonoses
11.
Korean J Parasitol ; 45(3): 205-11, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17876166

RESUMO

The infection status of mullets Mugil cephalus (n = 139) and gobies (n = 35) Acanthogobius flavimanus with metacercariae of Heterophyes nocens and Pygidiopsis summa was examined in 11 western, southern, and eastern coastal areas of the Republic of Korea, using a digestion technique. Heterophyid metacercariae were highly prevalent in mullets from western and southern coastal areas; Shinan-gun (100% for H. nocens and 100% for P. summa), Muan-gun (93% and 100%), Buan-gun (42% and 75%), Seocheon-gun (73% and 53%), Ganghwa-gun (47% and 100%), Sacheon-shi (47% and 77%), and Gangjin-gun (50% and 70%, respectively). Only 1 (10%) of 10 mullets from an eastern coastal area, i.e., Donghae-shi, was positive for P. summa metacercariae. Metacercarial densities were the highest in the trunk of mullets for H. nocens and the gill for P. summa. Gobies from Muan-gun were positive for H. nocens (40%) and P. summa metacercariae (40%), and gobies from Seocheon-gun revealed H. nocens metacercariae (20%). The metacercarial density was remarkably higher in mullets than in gobies. The results revealed that H. nocens and P. summa metacercariae are prevalent in mullets and gobies from coastal areas of the Republic of Korea, and the prevalence and intensity of infection vary according to geographical locality.


Assuntos
Doenças dos Peixes/epidemiologia , Heterophyidae/patogenicidade , Perciformes/parasitologia , Smegmamorpha/parasitologia , Infecções por Trematódeos/veterinária , Animais , Doenças dos Peixes/parasitologia , Geografia , Heterophyidae/isolamento & purificação , Coreia (Geográfico)/epidemiologia , Estágios do Ciclo de Vida , Vigilância da População , Prevalência , Infecções por Trematódeos/epidemiologia
12.
Dis Aquat Organ ; 71(1): 51-8, 2006 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-16922000

RESUMO

Infection of mussels Mytilus edulis L. by 2 trematode species was studied in a natural intertidal population in the Chupa inlet of the White Sea. The prevalence of metacercariae of Himasthla elongata (Mehlis, 1831) and Cercaria parvicaudata (Stunkard & Shaw, 1931) in mussels reached 100% in 3 to 4 yr old molluscs and remained at this level in older individuals. Infection intensity increased evenly with the age of the molluscan host, showing a tendency to decrease only in the oldest (9 yr old) mussels. These patterns of age dynamics of prevalence and infection intensity were associated with accumulation of trematode larvae in the course of the molluscs' lives. Ability of metacercariae to exist in mussels for long periods (at least 2.5 yr) was verified in the course of an experiment, during which infected molluscs were kept in a subtidal net cage. Decrease of infection intensity in the oldest individuals may reflect selective mortality of the most severely infected molluscs. Among mussels of the same age, higher infection intensity values occurred in larger individuals. This may be due to an enhanced pumping rate in large molluscs, which increases the probability of cercariae, free-living trematode larvae, infecting them via water currents.


Assuntos
Echinostomatidae/patogenicidade , Heterophyidae/patogenicidade , Mytilus edulis/parasitologia , Análise de Variância , Animais , Tamanho Corporal , Echinostomatidae/isolamento & purificação , Heterophyidae/isolamento & purificação , Fatores de Tempo
13.
Scand J Infect Dis ; 37(5): 388-90, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16051582

RESUMO

Haplorchis taichui is the minute intestinal fluke which parasitizes the small intestine of humans and other mammals. We present the pathology in the small intestine of 3 human cases caused by H. taichui. Microscopic examination revealed mucosal ulceration, mucosal and submucosal haemorrhages, fusion and shortening villi, chronic inflammation, and fibrosis of the submucosa. This finding clearly indicated H. taichui as pathogenic; thus prevention of infection and treatment should be paramount.


Assuntos
Heterophyidae/patogenicidade , Enteropatias Parasitárias/patologia , Intestino Delgado/patologia , Infecções por Trematódeos/patologia , Adulto , Idoso , Animais , Feminino , Heterophyidae/isolamento & purificação , Humanos , Enteropatias Parasitárias/parasitologia , Intestino Delgado/parasitologia , Jejuno/parasitologia , Jejuno/patologia , Masculino , Pessoa de Meia-Idade , Infecções por Trematódeos/parasitologia
14.
Artigo em Inglês | MEDLINE | ID: mdl-16438193

RESUMO

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.


Assuntos
Artocarpus , Heterophyidae/efeitos dos fármacos , Extratos Vegetais/farmacologia , Infecções por Trematódeos/prevenção & controle , Animais , Heterophyidae/patogenicidade , Humanos , Técnicas In Vitro
15.
Parasitol Int ; 53(4): 301-6, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15464439

RESUMO

The morphology of metacercariae of Massaliatrema misgurni Ohyama et al. (Ohyama et al., Parasitol Int 2001; 50; 267-71) was described, and their infectivity, egg output, growth and development in mice until day 35 post infection (PI) were studied. Metacercarial cysts from loaches imported from China to Japan were 199-349 microm in diameter and consisted of a very thick translucent outer layer and a refractile inner layer. Excysted metacercariae basically had the shape of miniature adults, and a pair of pre-developed testes but no other genital organs were recognized. The worm recovery rate from mice was 36.7-51.7% during days 3-7 PI, and decreased remarkably to 2.5 and 1.7% at days 28 and 35 PI. The prepatent period was 3-4 days, and the egg output quickly increased and sustained high levels at days 5-7 PI, then decreased suddenly at day 8 PI, and continued at a low level until day 28 PI. The size of the body and inner organs such as the oral sucker, pharynx, acetabulum, testes, ovary and seminal receptacle quickly increased until day 3 PI, and sustained at a plateau level until day 21 PI except testes which gradually decreased until 21 PI. The number of the uterine eggs increased with a short time lag compared to other genital organs and sustained a plateau level until day 21 PI. Compared with other Heterophyidae species, M. misgurni was characterized by the remarkably fast growth and development.


Assuntos
Heterophyidae/anatomia & histologia , Heterophyidae/crescimento & desenvolvimento , Infecções por Trematódeos/parasitologia , Animais , Fezes/parasitologia , Feminino , Heterophyidae/isolamento & purificação , Heterophyidae/patogenicidade , Interações Hospedeiro-Parasita , Masculino , Camundongos , Camundongos Endogâmicos ICR , Contagem de Ovos de Parasitas
16.
Korean J Parasitol ; 35(4): 239-44, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9446904

RESUMO

Genus Metagonimus has been a subject of taxonomic debates for several years. In morphological aspects, M. yokogawai has been thought to have three subtypes, namely Yokogawa type (M. yokogawai in strict sense), Miyata type and Koga type, But differences in the intestinal pathology induced by these subtypes have not been studied yet. In this study we compared the pathological reactions induced by M. yokogawai and Metagonimus Miyata type using proliferating cell nuclear antigen (PCNA) index. Metacercariae (Mc) of M. yokogawai were collected by artificial digestion of Plecoglossus altivelis and Mc of Metagonimus Miyata type were collected from Zacco platypus. Three hundreds Mc of each species were infected orally to ICR mice. The mice were sacrificed at 3, 6, 10, 16 and 23 days after infection and the small intestines were resected into three portions (proximal, middle, and distal). Immunohistochemical staining for PCNA was done using PC-10 (DAKO-PCNA, CA, USA). The PCNA indices in M. yokogawai infected group on the 6th and 23rd day after infection were lower than in the control and Miyata type infected groups (p < 0.05) from all of the three intestinal regions. On the other hand, the control group and Metagonimus Miyata type infected group did not make any differences in PCNA indices. The villus/crypt (V/C) ratio was also decreased significantly in M. yokogawai infected mice but not in Metagonimus Miyata type infected ones. It is suggested that M. yokogawai induce villous atrophy through a decrease in the cell proliferation at the crypt. The results of this study suggested that M. yokogawai induce more serious intestinal pathology than Metagonimus Miyata type.


Assuntos
Heterophyidae/classificação , Enteropatias Parasitárias/patologia , Intestino Delgado/patologia , Antígeno Nuclear de Célula em Proliferação/análise , Infecções por Trematódeos/patologia , Animais , Atrofia , Divisão Celular , Peixes , Heterophyidae/patogenicidade , Hiperplasia , Enteropatias Parasitárias/parasitologia , Intestino Delgado/citologia , Camundongos , Camundongos Endogâmicos ICR , Infecções por Trematódeos/parasitologia
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