174 research outputs found

    Assessment of bioaccumulation of cu and Pb in experimentally exposed spiders, Lycosa terrestris and Pardosa birmanica, using different exposure routes

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    © 2019, Springer-Verlag GmbH Germany, part of Springer Nature. Major concerns exist regarding the environmental and human health risks caused by exposure to heavy metals. Spiders are often used as a model in ecotoxicological studies to assess soil pollution. Here, we measured the bioaccumulation of copper (Cu) and lead (Pb) in spiders, Lycosa terrestris and Pardosa birmanica, by inductively coupled plasma mass spectrometry (ICP-MS). We investigated whether Cu and Pb accumulation differs according to different spider species, single versus combined metal exposure, and routes of exposure. Spiders were exposed to 10mM CuSO4 and 10mM PbCl2 solutions separately or in combination (10mM + 10mM) through different exposure routes (spiked soil and food) for 6weeks. The effect of metals on the survival and body mass of exposed and unexposed (control) spiders was determined. We found that in both spider species, accumulation of metals increased with exposure time. In single metal exposure, Cu accumulation from food was higher than soil exposure in both spider species, whereas the opposite was observed for Pb. The simultaneous uptake of Cu and Pb significantly decreased from food and soil, respectively. Soil exposure caused more accumulation of metals in L. terrestris than P. birmanica. Metal exposure via contaminated food caused higher mortality compared to soil exposure. Body mass of both spider species was significantly decreased and negatively correlated with metal’s concentration. Overall, our results show that bioaccumulation efficiency of Cu and Pb differs significantly in spiders exposed to metal’s mixture compared to single metal exposure and is dependent on the exposure route, the type of metal, and spider species. More understanding of the effects of exposure to metal mixture and exposure routes is essential for designing and supporting risk assessment and ecological monitoring programs

    Drug discovery against acanthamoeba infections: Present knowledge and unmet needs

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    Although major strides have been made in developing and testing various antiacanthamoebic drugs, recurrent infections, inadequate treatment outcomes, health complications, and side effects associated with the use of currently available drugs necessitate the development of more effective and safe therapeutic regimens. For any new anti-acanthamoebic drugs to be more effective, they must have either superior potency and safety or at least comparable potency and an improved safety profile compared to the existing drugs. The development of the so-called ‘nextgeneration’ anti-acanthamoebic agents to address this challenge is an active area of research. Here, we review the current status of anti-acanthamoebic drugs and discuss recent progress in identifying novel pharmacological targets and new approaches, such as drug repurposing, development of small interfering RNA (siRNA)-based therapies and testing natural products and their derivatives. Some of the discussed approaches have the potential to change the therapeutic landscape of Acanthamoeba infections

    Biology, epidemiology, clinical features, diagnosis, and treatment of selected fish-borne parasitic zoonoses

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    Fish-borne parasites have been part of the global landscape of food-borne zoonotic diseases for many decades and are often endemic in certain regions of the world. The past 20 years or so have seen the expansion of the range of fish-borne parasitic zoonoses to new geographic regions leading to a substantial public health burden. In this article, we summarize current knowledge about the biology, epidemiology, clinical characteristics, diagnosis, treatment and control of selected fish-borne helminthic diseases caused by parasitic roundworm (Anisakis), tapeworm (Dibothriocephalus), and fluke (Metagonimus). Humans acquire infection via consumption of raw or improperly cooked fish or fish products. The burden from these diseases is caused by morbidity rather than mortality. Infected patients may present with mild to severe gastrointestinal (eg, abdominal pain, diarrhea, and indigestion) or allergic manifestations. Patients are often admitted to the hospital or clinic with acute symptoms and no prior health problems and no travel history. Diagnosis is often established based on the detection of the diagnostic parasite stages (eg, eggs or tapeworm segments) in the patient’s feces. Sometimes imaging is required to exclude other causes and avoid unnecessary surgery. Dibothriocephalus and Metagonimus are mainly treated with praziquantel. Extraction of adult Dibothriocephalus or Anisakis larvae from the bowel ensures complete elimination of the parasites and prevents a relapse of infection. The development and implementation of more efficient food safety and public health strategies to reduce the burden of zoonotic diseases attributable to fish-borne parasites is highly desirable

    Diagnosis and Management of Acanthamoeba Keratitis: A Continental Approach

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    Acanthamoeba keratitis (AK) is a potentially blinding infection caused by protozoa found worldwide. The topical application of biguanides and diamidines is the most common anti-amoebic treatment for AK. In this study, we hypothesized that geographical location and socioeconomic status influence the management and treatment of AK. To test this hypothesis, we analyzed case reports and series of Acanthamoeba eye infections from different geographic regions to evaluate the association between diagnosis, treatment, and outcome worldwide. This study looked specifically at case reports of patients with diagnosed AK using bibliographic databases such as PubMed, BioMed Central, and Google Scholar, which were searched between 30 April 1990 and 1 May 2022. The search identified 38 eligible studies that provided data for 60 clinical cases of AK. The results indicated that current standard treatments are effective if the infection is identified early and that delays can lead to clinical symptoms, including permanent visual opacities. There was evidence suggesting an association between the treatment regimen practiced in certain geographic regions and treatment outcome. Patient access to medical facilities and economic background also had an influence on the treatment and outcome of AK. Further analysis of more case reports can expand our understanding of the influence of specific demographic and individual patient characteristics on the effectiveness and accessibility of AK medicines. Additionally, using a living systematic review approach to incorporate emerging evidence will reveal the relative merits of different treatment regimens for AK and outcomes

    Survey-based pilot study into the chosen therapy and prophylaxis used by UK primary care veterinary surgeons against canine angiostrongylosis

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    Canine Angiostrongylosis (CA), a gastropod-borne parasitic infection caused by the metastrongyloid nematode Angiostrongylus vasorum, is an important cause of significant morbidity to domestic dogs across the UK as well as in other European countries. This study aimed to ascertain the frequency at which particular drugs were used by primary care practitioners in the UK for therapy against and prophylaxis for CA. Primary care veterinary clinicians were surveyed using an online questionnaire and face-to-face or telephone interviews. Eighty-six veterinary surgeons responded. The majority of practices (n = 52) included lungworm in their standard anthelmintic protocols; moxidectin was the most common drug used for prophylaxis (n = 71). Fenbendazole was the most frequently selected drug, by 45% of vets, for treatment of confirmed cases of CA despite it being unlicensed for this purpose in the UK and the absence of a clear treatment protocol. The results of this pilot study provide an initial insight into the approach taken by primary care practitioners in their approach to CA. This provides an important starting point for future studies investigating the decision-making for CA amongst UK veterinary surgeons, particularly to clarify whether in a larger cohort an unlicensed drug remains the treatment of choice. The absence of a clear protocol for fenbendazole means that treatment of dogs affected by CA may be suboptimal, increasing the risk of morbidity and mortality

    Metabolic footprinting of extracellular metabolites of brain endothelium infected with Neospora caninum in vitro

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    BACKGROUND: The survival of the intracellular protozoan parasite Neospora caninum depends on its ability to adapt to changing metabolic conditions of the host cell. Thus, defining cellular and metabolic changes in affected target tissues may aid in delineating pathogenetic mechanism. We undertook this study to assess the metabolic response of human brain microvascular endothelial cells (HBMECs) to N. caninum infection in vitro. METHODS: HBMECs were exposed to N. caninum infection and the cytotoxic effects of infection were analyzed by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazoliumbromidin (MTT) assay and lactate dehydrogenase (LDH) release assay. Metabolic footprinting of the extracellular metabolites of parasite-infected and non-infected culture supernatant was determined by using targeted (Randox RX Imola clinical chemistry analyser) and unbiased RS (Raman microspectroscopy) approaches. RESULTS: The MTT assay did not reveal any cytotoxic effect of N. caninum challenge on host cell viability. Measurement of LDH activity showed that N. caninum significantly induced loss of cell membrane integrity in a time-dependent and dose-dependent manner compared to control cells. Targeted biochemical analysis revealed that beta hydroxybutyrate, pyruvate, ATP, total protein, non-esterified fatty acids, and triglycerides are significantly different in infected cells compared to controls. RS-based footprinting with principal component analysis (PCA) were able to correctly distinguish extracellular metabolites obtained from infected and control cultures, and revealed infection-related spectral signatures at 865 cm(−1), 984 cm(−1), 1046 cm(−1), and 1420 cm(−1), which are attributed to variations in the content of lipids and nucleic acids in infected cultures. CONCLUSIONS: The changing pattern of extracellular metabolites suggests that HBMECs are target of metabolic alterations in N. caninum infection, which seem to reflect the changing metabolic state of infected cells and constitute a level of information exchange that host and parasite use to coordinate activities

    Adverse effects of antipsychotics on micro-vascular endothelial cells of the human blood–brain barrier

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    Although the mechanisms of action of antipsychotics (APs) on neuronal function are well understood, very little is known about their effects on cells of the blood–brain barrier (BBB); one function of which is to limit the access of these amphiphilic compounds to the central nervous system. To address this question we have investigated the cytological and functional effects of four APs: chlorpromazine (CLP), haloperidol (HAL), risperidone (RIS) and clozapine (CLZ), at concentrations typical of high therapeutic dosage on a human brain microvascular endothelial cell (HBMEC) model of the BBB. At ~10 µM all four APs impaired the ability of HBMECs to reduce MTT which was followed by decreased Trypan blue exclusion and increased Lactate dehydrogenase release. These effects were associated with oxidative stress which was partly reversed by incubation in 10 mM glutathione. At their EC50 concentrations for MTT reduction, all four APs disrupted cellular ultrastructure and morphology. HAL, CPZ and CLZ increased Caspase -3, -8 and -9 activity, chromatin condensation and fragmentation, data indicative of apoptosis. These events were associated with decreased transcytosis of Evans blue and increased transendothelial potential difference and electrical resistance of this BBB model. These findings suggest that at high therapeutic concentrations, CPZ and CLZ are likely to incur cytoxic effects and apoptosis of BBB endothelia with an impairment of barrier functionality. Such events may underlie the aetiology of neuroleptic associated cerebral oedema and neuroleptic malignant syndrome

    First record of besnoitiosis caused by Besnoitia bennetti in donkeys from the UK

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    Background: The involvement of Besnoitia bennetti in skin pathologies was investigated in a series of 20 donkeys from the Donkey Sanctuary in England, in the 2013-2019 period. Methods: The initial histopathological finding of Besnoitia cysts in skin lumps that were presumed to be sarcoids in 2013 triggered our cognisance of this parasite and resulted in identification of a total of 20 cases. Histopathological examination of surgical biopsy samples collected from 8 live donkeys and tissue specimens from 12 deceased donkeys at post-mortem examination revealed the presence of Besnoitia cysts in all 20 donkeys. The indirect fluorescent antibody test (IFAT) and immunoblotting analysis showed the presence of anti-Besnoitia antibodies in archived serum samples from 4 deceased donkeys. Additionally, infection was evidenced in one live donkey based on IFAT and immunoblot analysis of tissue fluid of a dermal mass containing Besnoitia cysts, and real-time (RT)-PCR analysis and microsatellite genotyping of DNA isolated from the tissue of the same dermal mass confirmed the infection specifically as B. bennetti. Results: Both serological and microsatellite analyses confirmed the aetiology to be B. bennetti. Our findings suggested that in cases of skin masses such as sarcoids, the suspicion of B. bennetti infection should be borne in mind even when clinical and histopathology examination results are negative in order to avoid misdiagnosis. Conclusions: This case series documents, to our knowledge, the first report of B. bennetti infection in donkeys in the UK, indicating that donkey besnoitiosis has become noteworthy in the UK. Further investigations of the occurrence, epidemiological characteristics, and clinical manifestations of B. bennetti infection in donkeys and other equids are warranted.[Figure not available: see fulltext.

    Hepatic hydatid disease: four case reports

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    We report four cases who were referred to Mansoura University Teaching Hospital, Egypt suffering from abdominal pain and gastrointestinal manifestations. The patients' history was unremarkable, except that they had contact with dogs and live in rural communities. Laboratory findings showed peripheral blood eosinophilia, leucocytosis, and elevated liver enzymes. Serological tests were positive in three cases. Ultrasonography showed well-circumscribed cystic masses in the liver. Diagnosis of hydatid cysts was confirmed by computed tomography (CT). Surgical treatment along with chemotherapy was performed and all patients recovered well. The results of these cases support the notion that CT scan can led to increased clarity, regarding surgical management, because of discordance between radiographic and laboratory findings
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