Acta Parasitologica最新文献

Purpose

Knowledge of haploporid trematode larvae is very poor. Until recently, only scattered reports from the Black and Medditeranean Seas were known. The present research is the first report of haploporid cercariae S. cephali from the gastropod Hydrobia acuta inhabiting the Black Sea. Thus, the present study aimed to investigate the larvae of one species from the Haploporidae family.

Methods

Hydrobia acuta molluscs were collected in the estuary of the Chernaya River (the Black Sea) during 2011–2013 and examined for trematode larvae. Found parthenitae were drawn and preserved for DNA extractions. Morphological features were compared to nominal species, and molecular comparisons were made of the subunit ribosomal DNA with other Haploporidae species.

Results

The haploporid parthenitae were found in the gonads of Hydrobia acuta molluscs. Most of the morphological characteristics of the specimens investigated agree with those of Saccococoelium sp. and are closest to those of S. cephali by shape and length of the body, ratio of suckers, ratio of tail length to body, shape, and size of the pharynx. Phylogenetic analysis from our study generated with Bayesian algorithm showed that studied cercariae specimens from the Black Sea were within the hapolporine clade and closely related to S. cephali from Spain.

Conclusion

Morphological characteristics of cercariae emerging from Hydrobia acuta from the Black Sea and the analysis of partial 28S rDNA sequences support the conspecificity of the parasite with S. cephali mature worms from the Mediterranean Sea.

Introduction

Fascioliasis is a zoonotic condition precipitated by the trematode known as Fasciola spp. This parasite affected almost 2.4 to 17 million individuals in the world. The occurrence of liver abscesses is an infrequent phenomenon, potentially arising as a secondary outcome of cholangitis or hepatic inflammation. In this study, we have reported a case of a hepatic abscess induced by Fasciola spp.

Case Report

A 29-year-old male presented with generalized abdominal discomfort, primarily concentrated in the right upper quadrant, which had progressively worsened over the past seven months. The patient did mention a weight loss of approximately 10 kg during the course of their illness, along with increasing fatigue. Eosinophilia was seen too (35%). The stool exam test was negative. An enteroscopy was conducted, revealing no pathological abnormalities. Following this, the surgeon prescribed a surgical biopsy of the mass, which yielded a diagnosis of multiple eosinophilic granulomatous abscesses within the jejunal wall and mesentery. The Fasciola IgG test returned a positive result. After of follow-up, the patient fully recovered.

Conclusion

Fascioliasis should be considered in the differential diagnoses of liver abscesses. Because of earlier diagnosis, can be avoided of invasive diagnostic tests and therapeutic interventions can be started earlier.

Purpose

The objective of the present work was to evaluate the effect of an ethyl acetate extract of Artemisia ludoviciana on the viability of adult Fasciola hepatica parasites and eggs.

Methods

The collection of plant material was performed as described in previous reports. The dried material was macerated with ethyl acetate. Ovicidal assays were performed at concentrations of 100, 200, 300, 400 and 500 mg/L A. ludoviciana extract. Bioassays of fasciolicidal efficacy in adult specimens of F. hepatica were performed at extract concentrations of 125, 250, 375 and 500 mg/L. The effects of triclabendazole, a reference drug, and artemisinin were also evaluated.

Results

The ovicidal effectiveness of the extracts obtained after 16 h of incubation at concentrations of 100, 200, 300, 400 and 500 mg/L was 48%, 52%, 87%, 89% and 92%, respectively (p < 0.05), and the fasciolicidal efficiencies during the first 24 h post-treatment ranged from 82 to 100% (p < 0.05). In both cases, scanning electron microscopy revealed damage to the shells of the eggs treated with the extract, compromising their stability. In adult fasciolae, alterations to the integument that resulted in its erosion and detachment were observed. Histopathological studies of the affected specimens revealed damage to the tegumentary and subtegumentary cells and alterations in the ovaries, testicles and intestine. This damage was more severe after treatment with the extract than after treatment with the other compounds.

Methods

Extract of A. ludoviciana causes damage to the tegument, intestine, ovaries, testes and eggs of F. hepatica.

Background

The genus Stilestrongylus (Freitas, Lent, and Almeida, 1937) is defined by having 24 or more subequal cuticular ridges, an asymmetrical caudal bursa, and a hypertrophied genital cone. It comprises 25 recognized species, mainly parasitizing cricetids, and shows significant diversification linked to the evolution of its hosts. Stilestrongylus magnumspiculum n. sp. is a newly described nematode species identified in the small intestine of the rodent Euryoryzomys russatus (Cricetidae, Sigmodontinae) from the Atlantic Forest of Northeast Brazil. This study aims to characterize the new species and its prevalence in host populations.

Methods

A total of 43 Euryoryzomys russatus individuals were collected and analyzed for parasitic infections. Morphological features of Stilestrongylus magnumspiculum n. sp. were examined, focusing on the number of ridges, synlophe characteristics, caudal bursa type, lobe hypertrophy, and the spicule length to body length ratio.

Results

The new species exhibited a prevalence of 21% among the sampled hosts. Distinctive morphological features were observed, including:the synlophe structure exhibited specific ridge patterns that differentiate it from other species within the genus; the caudal bursa was identified as a type 2-2-1; hypertrophy of the right lobe was observed, indicating notable morphological adaptation; rays 4 and 5 were found to be equivalent in size and diverged at the distal end; the spicule length to body length ratio (SpL/BL) was measured at 30–36%, representing the largest ratio recorded for the genus. In comparison, other Stilestrongylus species displayed the following ratios: S. rolandoi (21–33%), S. lanfrediae (25–29%), S. kaaguyporai (20–24%), S. inexpectatus (20–23%), and S. stilesi (26–28%).

Conclusions

This report presents Stilestrongylus magnumspiculum n. sp. as a new species of nematode, contributing to the diversity of the genus Stilestrongylus. The findings underscore the importance of studying host-parasite interactions within the Atlantic Forest ecosystem and provide a basis for future ecological and parasitological research.

Introduction

Anacanthorus silvoi n. sp. (Dactylogyridae, Anacanthorinae) is described from the gills of Hoplias aff. malabaricus (Bloch, 1794) from the Salgado River, Ceará state, Brazil.

Materials and Methods

The monogeneans were affixed onto slides using Gray and Wess’s medium for examination of their sclerotized structures. For analysis of internal organs, a single specimen was preserved in 5% formalin, stained with Gomori’s trichrome, and mounted in Gray and Wess’s medium.

Results

Anacanthorus silvoi n. sp. is characterized by having a short broad tube MCO with a medial constriction (i.e., MCO with distal region wider than the proximal region, and flexed lateral flap in the distal region in A. cururutuiensis and a MCO with a small projection in the form of a hook in the distal region in A. siphonocommus).

Conclusions

The present study corroborates previous studies that the absence of an accessory piece is a characteristic shared by all Anacanthorus members parasites of Erythrinidae.

Benign theileriosis, caused by the members of the Theileria orientalis complex, can develop fatal clinical outbreaks characterized by acute respiratory manifestation in stressful conditions. This report describes the molecular diagnosis and clinical management of a recently transported buffalo calf with severe Theileria buffeli infection and associated acute pneumonia. A five-month-old male buffalo calf having an inter-state travel history three days back was presented with pyrexia, anorexia, weakness, mucoid rhinorrhoea, dyspnoea and diarrhoea from the day of procurement. The history and physical examination revealed a clinical presentation similar to shipping fever. Whereas, severe parasitemia of Theileria spp. with anaemia, thrombocytopenia and granulopenia were evident on laboratory investigation. The Theileria spp. infection was confirmed by PCR method using specific primers and the authentication was made by detailed sequence analysis. The small subunit rRNA was amplified using universal apicomplexan primers and the phylogenetic analysis was carried out for further characterisation. The animal was stabilized by steroid nebulization therapy and the specific chemotherapy was instigated using buparvaquone and sulphamethoxazole-trimethoprim combination. Supportive medications like non-steroidal anti-inflammatory drugs, antihistamines, antidiarrhoeals and vitamins were provided symptomatically. The animal showed a good response to therapy and recovered from parasitemia by day 10 and the molecular clearance was later confirmed on day 70 of therapy. The present case of Theileria buffeli infected buffalo calf with acute respiratory signs points towards the possible hemoparasitic outbreaks in transport-stressed animals with the signs of shipping fever-associated syndrome.

Purpose

The Myxozoa class is characterized by parasites that have valves joined by a suture line and polar capsules containing eversible spiral filamento and this class is considered an obligate parasite. The genus Ceratomyxa has approximately 300 species described in fish, both marine and freshwater fish, mainly infecting the gallbladder, but also occurring in the urinary bladder. This study describes a new species of Ceratomyxa in the Amazon region for Pimelodella cristata.

Methods

For these analyses, the fish were desensitized by means of a medullary section with the aid of a sharp metallic instrument. With the fish desensitized, the entire body surface was examined under a binocular stereoscopic microscope. The gallbladder fragments were collected and fixed in Davidson for histological analyses and in ethanol for molecular analyses.

Results

This parasite was found in the host’s gallbladder, with elongated spores in a decreasing shape in sutural view, measuring 1.64 ± 0.6 μm in length and 17.13 ± 2.6 μm in width. The polar capsules had a spherical shape of equal size and measured 1.36 ± 0.17 μm in length and 0.9 ± 0.05 μm in width, and each polar capsule contained 4 to 5 turns.

Conclusion

Morphological and phylogenetic analyzes denote that this is a new species of the genus Ceratomyxa.

Purpose

Epidemiological studies on amoebic infections are complicated due to morphologically identical and clinically important Entamoeba species. Therefore, newer, simpler, and more economical diagnostic techniques are required for differentiating clinically important Entamoeba species.

Methods

We developed a single-round multiplex PCR assay to identify E. histolytica, E. moshkovskii, E. dispar, E. bangladeshi, and E. coli. Primers were designed based on variations in 18 S rRNA sequences. Sensitivity and specificity were assessed using known positive and negative samples. Furthermore, we screened 472 diarrheal samples using this technique alongside the reference PCR method to evaluate its suitability for epidemiological studies and clinical diagnosis. DNA sequencing and phylogenetic analysis of the isolates were conducted. All statistical analyses of the data were performed using GraphPad Prism.

Results

The designed primers successfully yielded species-specific PCR products of different sizes as expected. We did not observe any non-specific amplifications of the primer set. The diagnostic performance was also convincing. After screening clinical samples using the method, we observed that 2.33% (n = 11) tested positive for E. moshkovskii, 1.06% (n = 5) tested positive for E. histolytica, and 0.85% (n = 4) tested positive for E. bangladeshi in the studied area. DNA sequencing further confirmed the identified species. The constructed phylogenetic tree also demonstrated clear separation of the detected species lineages.

Conclusion

The study suggests the multiplex PCR assay could be a reliable diagnostic tool for amoebic infections. This study is particularly significant as it marks the first reported occurrence of E. bangladeshi since its documentation in South Africa and its native Bangladesh.

Purpose

In this study, we present the case of a children who was followed up for recurrent visceral leishmaniasis and diagnosed with IL-12Rβ1 deficiency.

Methods

A female patient who received Bacille Calmette-Guérin (BCG) vaccine 2 months after birth and developed visceral leishmaniasis at the age of 91 months was subsequently diagnosed with IL-12Rβ1 deficiency. The patient’s diagnosis and treatment process were examined retrospectively.

Results

IL-12Rβ1 deficiency is an autosomal recessive disease characterized by susceptibility to recurrent and/or severe infections caused by weakly pathogenic mycobacteria and salmonella. Infections with other intramacrophagic organisms may also occur, although rarely. Based on this information, it is believed that the mutation in the IFN-γ/IL-12 axis in our patient predisposed her to recurrent Leishmania infections.

Conclusion

This study adds to the limited literature on IL12RB1 deficiency as a cause of VL. Patients diagnosed with VL should be evaluated immunologically, as recurrent Leishmania infections may occur in those with IL-12Rβ1 defects.

Background

Inflammatory bowel disease (IBD) is a chronic and recurrent disease of the gastrointestinal tract that enhances the chance of developing colorectal cancer. Since standard treatments such as Mesalazine have limited effectiveness and are often accompanied by numerous side effects, the use of immune modulators derived from worms has been proposed as a new immunotherapy method for inflammatory diseases such as ulcerative colitis. The aim of this study is to investigate the protective effects of D. dendriticum egg antigen on DSS-induced colitis in C57BL/6 mice.

Methods

D. dendriticum egg antigen was extracted and DSS (3.5%) was used to induce colitis in mice. Treatment and prophylaxis included intraperitoneal injections of D. dendriticum egg antigen. Histopathological indicators and the disease activity index (DAI), including weight loss, rectal bleeding, stool consistency, and rectal prolapse, were used to assess the severity of colitis. Real-time PCR measured the expression of transforming growth factor-β (TGF-β) and interleukin-17 (IL-17), while ELISA determined the concentration of these cytokines.

Results

Treatment with D. dendriticum egg antigen significantly improved the clinical symptoms and decreased the severity of DSS-induced colitis. Furthermore, D. dendriticum egg antigen increased the expression of TGF-β mRNA and reduced the expression of IL-17 mRNA, leading to a positive adjustment in the regulation of proteins and reduction of inflammatory proteins. As a result, the macroscopic, microscopic inflammation and activity index (DAI) of DSS-induced decreased.

Conclusion

D. dendriticum egg antigen provides a promising new way to modulate the immune system and improve ulcerative colitis.