The human pathogens Plasmodium and Schistosoma are each responsible for over 200 million infections annually, especially in low- and middle-income countries. There is a pressing need for new drug targets for these diseases, driven by emergence of drug-resistance in Plasmodium and an overall dearth of drug targets against Schistosoma. Here, we explored the opportunity for pathogen-hopping by evaluating a series of quinoxaline-based anti-schistosomal compounds for their activity against P. falciparum. We identified compounds with low nanomolar potency against 3D7 and multidrug-resistant strains. In vitro resistance selections using wildtype and mutator P. falciparum lines revealed a low propensity for resistance. Only one of the series, compound 22, yielded resistance mutations, including point mutations in a non-essential putative hydrolase pfqrp1, as well as copy number amplification of a phospholipid-translocating ATPase, pfatp2, a potential target. Notably, independently generated CRISPR-edited mutants in pfqrp1 also showed resistance to compound 22 and a related analogue. Moreover, previous lines with pfatp2 copy number variations were similarly less susceptible to challenge with the new compounds. Finally, we examined whether the predicted hydrolase activity of PfQRP1 underlies its mechanism of resistance, showing that both mutation of the putative catalytic triad and a more severe loss of function mutation elicited resistance. Collectively, we describe a compound series with potent activity against two important pathogens and their potential target in P. falciparum.

• MeSH
• Antimalarials * pharmacology   MeSH
• Quinoxalines * pharmacology   MeSH
• Drug Resistance drug effects   MeSH
• Humans MeSH
• Plasmodium falciparum * drug effects   MeSH
• Protozoan Proteins metabolism   genetics   MeSH
• Schistosoma drug effects   MeSH
• Schistosomiasis drug therapy   MeSH
• Malaria, Falciparum drug therapy   parasitology   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH

Cryptosporidium mortiferum, a parasite transmitted by squirrels, is beginning to spread in Europe. C. mortiferum was detected in a symptomatic human. A 44-year-old man from the Czech Republic suffered from gastroenteritis characterized by abdominal pain, nausea, and loose stools. Molecular analyses confirmed the XIVaA20G2T1 subtype in the patient's stool. At the same time, the same subtype of C. mortiferum was detected in three red squirrels and two ground squirrels in the area where the patient lived. The intensity of the infection was significantly higher in the red squirrels that died, while the ground squirrels showed no symptoms. The results of the study indicate that red squirrels and ground squirrels are the reservoirs for the infection.

• MeSH
• Cryptosporidium * isolation & purification   genetics   classification   MeSH
• Adult MeSH
• Feces * parasitology   MeSH
• Phylogeny MeSH
• Gastroenteritis parasitology   veterinary   MeSH
• Cryptosporidiosis * parasitology   epidemiology   MeSH
• Humans MeSH
• Sciuridae * parasitology   MeSH
• Disease Reservoirs parasitology   MeSH
• Zoonoses * parasitology   MeSH
• Animals MeSH
• Check Tag
• Adult MeSH
• Humans MeSH
• Male MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Case Reports MeSH
• Geographicals
• Czech Republic MeSH

PURPOSE: A new high-resolution next-generation sequencing (NGS)-based method was established to type closely related European type II Toxoplasma gondii strains. METHODS: T. gondii field isolates were collected from different parts of Europe and assessed by whole genome sequencing (WGS). In comparison to ME49 (a type II reference strain), highly polymorphic regions (HPRs) were identified, showing a considerable number of single nucleotide polymorphisms (SNPs). After confirmation by Sanger sequencing, 18 HPRs were used to design a primer panel for multiplex PCR to establish a multilocus Ion AmpliSeq typing method. Toxoplasma gondii isolates and T. gondii present in clinical samples were typed with the new method. The sensitivity of the method was tested with serially diluted reference DNA samples. RESULTS: Among type II specimens, the method could differentiate the same number of haplotypes as the reference standard, microsatellite (MS) typing. Passages of the same isolates and specimens originating from abortion outbreaks were identified as identical. In addition, seven different genotypes, two atypical and two recombinant specimens were clearly distinguished from each other by the method. Furthermore, almost all SNPs detected by the Ion AmpliSeq method corresponded to those expected based on WGS. By testing serially diluted DNA samples, the method exhibited a similar analytical sensitivity as MS typing. CONCLUSION: The new method can distinguish different T. gondii genotypes and detect intra-genotype variability among European type II T. gondii strains. Furthermore, with WGS data additional target regions can be added to the method to potentially increase typing resolution.

• MeSH
• Genetic Variation MeSH
• Genotype MeSH
• Humans MeSH
• Multiplex Polymerase Chain Reaction MeSH
• Polymorphism, Restriction Fragment Length MeSH
• DNA, Protozoan genetics   MeSH
• Pregnancy MeSH
• Toxoplasma * genetics   MeSH
• High-Throughput Nucleotide Sequencing MeSH
• Check Tag
• Humans MeSH
• Pregnancy MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

Equine neosporosis is an intracellular protozoan disease with a global distribution, affecting a diverse range of warm-blooded animals. Neospora caninum Dubey, Carpenter, Speer, Topper et Uggla, 1988 is associated with foetal loss, neurological disease and abortion in equids. No information was available regarding equine N. caninum infection among equids in Iraq. Thus, the aim of this study was to determine the prevalence rate of N. caninum in equines by using a competitive enzyme-linked immunosorbent assay (c-ELISA). A total of 329 blood samples randomly selected from equines, comprising 268 horses and 61 donkeys were examined. The seroprevalence rate of N. caninum was determined as 46% (28/61) for donkeys and 24% (64/268) for horses. The prevalence of N. caninum indicated a significantly higher risk of infection in donkeys compared to horses (P < 0.001). However, the odds of N. caninum infection in draught equids were 8.2 times greater than other equids with a significant difference (P < 0.001). The current study revealed no significant differences in the prevalence of N. caninum across various genders, breeds, clinical statuses, disease histories and among equids that had contact with dogs. While outdoor feeding and mixed (grazing), showed a significant difference (P = 0.003) and (P = 0.75), respectively, in the presence of antibodies against N. caninum compared to indoor feeding (stable). Moreover, the odds of infection in equids with a history of late abortion were 4.8 times higher than those without such a history of abortion (2.20-10.56) with statistical significance (P < 0.001).

• MeSH
• Enzyme-Linked Immunosorbent Assay * veterinary   MeSH
• Equidae * parasitology   MeSH
• Coccidiosis * veterinary   epidemiology   parasitology   MeSH
• Horses MeSH
• Horse Diseases * epidemiology   parasitology   MeSH
• Neospora * isolation & purification   MeSH
• Prevalence MeSH
• Antibodies, Protozoan blood   MeSH
• Seroepidemiologic Studies MeSH
• Animals MeSH
• Check Tag
• Male MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Geographicals
• Iraq MeSH

Cíl: Zjistit výskyt potenciálně patogenních druhů babesií pro člověka v klíšťatech a v krvi psů a jelenů ve vybraných regionech České republiky. Prevalenci Babesia spp. v klíšťatech porovnat s výskytem jiných patogenů přenášených klíšťaty jako Borrelia spp., Anaplasma spp., Rickettsia spp. Materiál a metody: Vzorky klíšťat byly jednotlivě homogenizovány, ze vzorků klíšťat a krve živočichů provedena izolace DNA. Detekce Babesia spp. byla stanovena metodou PCR 18S rRNA genu a sekvenační analýzou PCR produktů určeny jednotlivé druhy babesií. Výsledky: V letech 2014–2016 byla analyzována klíšťata a krev psů a jelenů na různých místech České republiky. Ze souboru 675 klíšťat Ixodes ricinus dosahovala pozitivita na přítomnost Babesia spp. hodnot od 0,0 do 3,3 %. Sekvenační analýzou byly v klíšťatech identifikovány druhy Babesia venatorum, Babesia microti (patogenní druhy pro člověka) a druh Babesia capreoli. Prevalence Babesia spp. v klíšťatech byla v porovnání s výskytem jiných patogenů jako Borrelia burgdorferi s. l. (29,3 %), Anaplasma phagocytophilum (4,9 %) nižší a srovnatelná s Rickettsia spp. (1,6 %). U třetiny pozitivních klíšťat na babesie byla zjištěna koinfekce s Borrelia burgdorferi s. l. (B. venatorum – Borrelia garinii, Borrelia afzelii a B. microti – B. afzelii). Ze 109 vzorků krve psů bylo 3,7 % pozitivních na Babesia spp. s výskytem druhů Babesia gibsoni a Babesia vulpes. Z 50 vzorků krve jelenů z přírodního ekosystému dosahovala pozitivita 4,0 %. Identifikován byl druh Babesia divergens, nejvíce patogenní druh Babesia spp. pro člověka. Z 80 vzorků krve jelenů chovaných na farmách bylo pozitivních 5,0 % s výskytem druhu Babesia odocoilei. Nukleotidové sekvence babesií způsobujících humánní babesiózu byly zaslány do genové banky a přijaty pod čísly ON892053 (B. venatorum), ON892061 (B. microti), ON892067 (B. divergens). Závěr: Metodou PCR 18S rRNA genu a sekvenací amplikonů byly na území České republiky detekovány tři druhy babesií patogenních pro člověka: B. divergens, B. venatorum, B. microti. Výskyt těchto druhů babesií znamená potenciální riziko onemocnění babesiózou, zejména pro asplenické a imunokompromitované pacienty. Zjištěné koinfekce s Borrelia burgdorferi s. l. mohou být příčinou komplikovaného průběhu onemocnění.

Aim: To determine the occurrence of species of Babesia potentially pathogenic for humans in ticks and in the blood of dogs and deer in selected regions of the Czech Republic. To compare the prevalence of Babesia spp. in ticks with that of other tick-borne pathogens, such as Borrelia spp., Anaplasma spp., and Rickettsia spp. Material and Methods: Tick samples were individually homogenized. DNA was isolated from tick samples and animal blood. The detection of Babesia spp. was based on PCR of the 18S rRNA gene, and the identification to the species level was done by sequencing analysis of the PCR products. Results: In 2014–2016, ticks and blood of dogs and deer collected in various areas of the Czech Republic were analyzed. In a set of 675 Ixodes ricinus ticks, the positivity rate for Babesia spp. varied from 0.0 to 3.3 %. The species Babesia venatorum, Babesia microti (both pathogenic for humans), and Babesia capreoli were identified in ticks by sequencing analysis. The prevalence of Babesia spp. in ticks compared to that of other pathogens such as Borrelia burgdorferi s. l. (29.3 %) or Anaplasma phagocytophilum (4.9 %) was lower and comparable to that of Rickettsia spp. (1.6 %). Co-infection with Borrelia burgdorferi s.l (B. venatorum – Borrelia garinii, Borrelia afzelii, and B. microti – B. afzelii) was found in a third of Babesia spp. positive ticks. Out of 109 dog blood samples, 3.7 % were positive for Babesia spp., specifically Babesia gibsoni and Babesia vulpes. Of 50 blood samples of wild deer from the natural ecosystem, the positivity rate reached 4.0 %. The species Babesia divergens, a major human pathogen, was identified. Out of 80 blood samples from farmed deer, 5.0 % were positive for the species Babesia odocoilei. Nucleotide sequences of the agents causing human babesiosis were deposited in the gene bank under accession numbers ON892053 (B. venatorum), ON892061 (B. microti), and ON892067 (B. divergens). Conclusions: Using PCR of the 18S rRNA gene and amplicon sequencing, three species of Babesia causing human babesiosis were detected in the Czech Republic: B. divergens, B. venatorum, and B. microti. Babesia spp. pathogenic for humans pose a potential risk especially in asplenic and immunocompromised patients. The detected co-infections with Borrelia spp. can be the cause of a complicated course of the disease.

• MeSH
• Babesia microbiology   MeSH
• Babesiosis * epidemiology   blood   transmission   MeSH
• Borrelia burgdorferi MeSH
• Molecular Diagnostic Techniques methods   MeSH
• Ticks * microbiology   MeSH
• Coinfection diagnosis   transmission   MeSH
• Blood microbiology   MeSH
• Humans MeSH
• Tick-Borne Diseases epidemiology   transmission   prevention & control   MeSH
• Polymerase Chain Reaction methods   MeSH
• Dogs * microbiology   MeSH
• Deer * blood   microbiology   MeSH
• Check Tag
• Humans MeSH
• Dogs * microbiology   MeSH
• Geographicals
• Czech Republic MeSH

Malaria remains a major health hazard for humans, despite the availability of efficacious antimalarial drugs and other interventions. Given that the disease is often deadly for children under 5 years and pregnant women living in malaria-endemic areas, an efficacious vaccine to prevent transmission and clinical disease would be ideal. Plasmodium, the causative agent of malaria, uses proteases and protease inhibitors to control and process to invade host, modulate host immunity, and for pathogenesis. Plasmodium parasites rely on these proteases for their development and survival, including feeding their metabolic needs and invasion of both mosquito and human tissues, and have thus been explored as potential targets for prophylaxis. In this chapter, we have discussed the potential of proteases like ROM4, SUB2, SERA4, SERA5, and others as vaccine candidates. We have also discussed the role of some protease inhibitors of plasmodium and mosquito origin. Inhibition of plasmodium proteases can interrupt the parasite development at many different stages therefore understanding their function is key to developing new drugs and malaria vaccines.

• MeSH
• Protease Inhibitors pharmacology   therapeutic use   MeSH
• Humans MeSH
• Malaria drug therapy   immunology   parasitology   prevention & control   MeSH
• Plasmodium * drug effects   enzymology   immunology   physiology   MeSH
• Peptide Hydrolases * immunology   MeSH
• Protozoan Proteins * antagonists & inhibitors   immunology   MeSH
• Malaria Vaccines * immunology   MeSH
• Vaccine Development MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH

In this review, I take the first-person perspective of a neuroscientist interested in Toxoplasma gondii (Nicolle et Manceaux, 1908). I reflect on the value of behavioural manipulation as a perturbation tool to understand the organisation of behaviour within the brain. Toxoplasma gondii infection reduces the aversion of rats to the olfactory cues of cat presence. This change in behaviour is one of the often-discussed exemplars of host-parasite coevolution, culminating in the manipulation of the host behaviour for the benefit of the parasite. Such coevolution also means that we can use host-parasite systems as tools to derive fundamental insights about the host brain itself.

• MeSH
• Behavior, Animal * physiology   MeSH
• Host-Parasite Interactions * MeSH
• Rats MeSH
• Humans MeSH
• Toxoplasma * physiology   MeSH
• Toxoplasmosis, Animal parasitology   MeSH
• Toxoplasmosis parasitology   MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Review MeSH

Toxoplasmosis is caused by Toxoplasma gondii (Nicolle et Manceaux, 1908), a coccidian protist (Apicomplexa). It has a strong predilection for infecting the central nervous system. Researchers have therefore investigated its association with several neurological and psychiatric disorders, including Alzheimer's disease, attention-deficit hyperactivity disorder, autism, bipolar disorder, cerebral palsy, depression, Guillain-Barre syndrome, multiple sclerosis, obsessive compulsive disorder, Parkinson's disease, personality disorders, and schizophrenia. Among these disorders the strongest evidence for a role of T. gondii exists for psychosis in general and schizophrenia in particular. This paper reviews the origins of this association, briefly summarises the current evidence in support, and discusses future research strategies.

• MeSH
• Humans MeSH
• Schizophrenia * MeSH
• Toxoplasma physiology   MeSH
• Toxoplasmosis * complications   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Review MeSH

Over the last decade, research on the most studied parasite, Plasmodium falciparum, has disclosed significant findings in protease research. Detailed descriptions of the individual roles of protease isoenzymes from various protease classes encoded by the parasite genome have been elucidated, along with their functional and biochemical characterizations. These insights have enabled the development of innovative chemotherapy using low molecular weight inhibitors targeting specific molecular sites. Progress has been made in understanding the proteolytic cascade associated with the apical complex, particularly the roles of aspartyl proteases plasmepsins IX and X as master regulators. Additionally, advancements in direct and alternative methods of proteasome inhibition and expression regulation have been achieved. Research on digestive/food vacuole-associated proteases, with a focus on essential metalloproteases, has also seen significant developments. The rise of extensive genomic datasets and functional genomic tools for other parasitic organisms now allows these approaches to be applied to the study and treatment of other, less known parasitic diseases, aiming to uncover specific biological mechanisms and develop innovative, less toxic chemotherapies.

• MeSH
• Antimalarials * pharmacology   therapeutic use   MeSH
• Protease Inhibitors * therapeutic use   MeSH
• Humans MeSH
• Malaria drug therapy   MeSH
• Plasmodium falciparum * enzymology   drug effects   genetics   MeSH
• Peptide Hydrolases metabolism   genetics   MeSH
• Malaria, Falciparum drug therapy   parasitology   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Review MeSH

Leucocytozoon infection has been observed to impact the reproductive ecology and physiology of avian hosts, but its influence on nestling survival remains unclear. We investigated the effect of Leucocytozoon infection intensity, determined through triplicate PCR sample analyses, on the survival of 256 boreal owl (Aegolius funereus) nestlings during an 8-yr study. Contrary to our expectations, the survival probability of boreal owl nestlings was not influenced by their Leucocytozoon infection intensity. Nestling age and Leucocytozoon infection intensity in male and female parents also did not impact nestling survival. Instead, food abundance and hatching order were the key factors influencing nestling survival. Additionally, we observed a significantly higher Leucocytozoon infection intensity in male parents compared to female parents and nestlings. We suggest a distinct division of parental roles may lead females and nestlings staying within the nest boxes (cavities) to experience lower exposure to potential vectors transmitting blood parasites than their male counterparts. Our study shows that Leucocytozoon disease may not be lethal for boreal owl chicks, exhibiting a below-average infection intensity compared to their male parents.

• MeSH
• Haemosporida physiology   MeSH
• Microsporidiosis veterinary   MeSH
• Bird Diseases * parasitology   mortality   MeSH
• Strigiformes * physiology   MeSH
• Animals MeSH
• Check Tag
• Male MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH