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Parasite (Paris, France) 2024The plerocercoid larvae of Spirometra mansoni are etiological agents of human and animal sparganosis. Annexins are proteins with important roles in parasites. However,...
The plerocercoid larvae of Spirometra mansoni are etiological agents of human and animal sparganosis. Annexins are proteins with important roles in parasites. However, our knowledge of annexins in S. mansoni is still inadequate. In this study, 18 new members of the Annexin (ANX) family were characterized in S. mansoni. The clustering analysis demonstrated that all the SmANXs were divided into two main classes, consistent with the patterns of conserved motif organization. The 18 SmANXs were detected at all developmental stages (plerocercoid, adult, and egg) and displayed ubiquitous but highly variable expression patterns in all tissues/organs studied. The representative member rSmANX18 was successfully cloned and expressed. The protein was immunolocalized in the tegument and parenchyma of the plerocercoid and in the tegument, parenchyma, uterus and egg shell of adult worms. The recombinant protein can bind phospholipids with high affinity in a Ca-dependent manner, shows high anticoagulant activity and combines with FITC to recognize apoptotic cells. Annexin gene polymorphism and conservative core motif permutation were found in both cestodes and trematodes. SmANXs also revealed high genetic diversity among Platyhelminthes of medical interest. Our findings lay a foundation for further studies on the biological functions of ANXs in S. mansoni as well as other taxa in which ANXs occur.
Topics: Animals; Spirometra; Phylogeny; Annexins; Amino Acid Sequence; Helminth Proteins; Multigene Family; Humans; Female; Genetic Variation; Recombinant Proteins
PubMed: 38912916
DOI: 10.1051/parasite/2024034 -
Neural Development Jun 2024Acoel flatworms have played a relevant role in classical (and current) discussions on the evolutionary origin of bilaterian animals. This is mostly derived from the... (Review)
Review
Acoel flatworms have played a relevant role in classical (and current) discussions on the evolutionary origin of bilaterian animals. This is mostly derived from the apparent simplicity of their body architectures. This tenet has been challenged over the last couple of decades, mostly because detailed studies of their morphology and the introduction of multiple genomic technologies have unveiled a complexity of cell types, tissular arrangements and patterning mechanisms that were hidden below this 'superficial' simplicity. One tissue that has received a particular attention has been the nervous system (NS). The combination of ultrastructural and single cell methodologies has revealed unique cellular diversity and developmental trajectories for most of their neurons and associated sensory systems. Moreover, the great diversity in NS architectures shown by different acoels offers us with a unique group of animals where to study key aspects of neurogenesis and diversification od neural systems over evolutionary time.In this review we revisit some recent developments in the characterization of the acoel nervous system structure and the regulatory mechanisms that contribute to their embryological development. We end up by suggesting some promising avenues to better understand how this tissue is organized in its finest cellular details and how to achieve a deeper knowledge of the functional roles that genes and gene networks play in its construction.
Topics: Animals; Nervous System; Neurogenesis; Platyhelminths; Biological Evolution; Neurons
PubMed: 38907301
DOI: 10.1186/s13064-024-00187-1 -
Parasitology Research Jun 2024Introduced species have a major impact on freshwater ecosystems, particularly on islands. Numerous fish species have been introduced in Corsica (Mediterranean island,...
Introduced species have a major impact on freshwater ecosystems, particularly on islands. Numerous fish species have been introduced in Corsica (Mediterranean island, southern France) as part of planned programs or clandestinely. The introduction of non-native freshwater fish species can have a range of impacts on the recipient ecosystem, including through the co-introduction of its pathogens. A sample of introduced perch Perca fluviatilis Linnaeus, 1758 from the artificial reservoir of Padula was examined following a report of parasites by an angler. The analyses revealed the occurrence of Eustrongylides sp. (Nematoda) and Clinostomum complanatum (Digenea), two zoonotic parasites in P. fluviatilis. Both parasites are reported for the first time in France. Eustrongylides sp. and C. complanatum may have been introduced with their fish intermediate hosts or through their final bird hosts. The occurrence of the two parasites raises concerns from both a veterinary and human health perspective as they can use a wide range of amphibians as intermediate hosts and can be acquired in humans through the consumption of raw or undercooked fish.
Topics: Animals; France; Fish Diseases; Perches; Introduced Species; Trematoda; Zoonoses; Trematode Infections; Islands; Humans
PubMed: 38898308
DOI: 10.1007/s00436-024-08264-4 -
Nature Communications Jun 2024Schistosomiasis is a neglected tropical disease caused by Schistosoma parasites. Schistosoma are obligate parasites of freshwater Biomphalaria and Bulinus snails, thus...
Schistosomiasis is a neglected tropical disease caused by Schistosoma parasites. Schistosoma are obligate parasites of freshwater Biomphalaria and Bulinus snails, thus controlling snail populations is critical to reducing transmission risk. As snails are sensitive to environmental conditions, we expect their distribution is significantly impacted by global change. Here, we used machine learning, remote sensing, and 30 years of snail occurrence records to map the historical and current distribution of forward-transmitting Biomphalaria hosts throughout Brazil. We identified key features influencing the distribution of suitable habitat and determined how Biomphalaria habitat has changed with climate and urbanization over the last three decades. Our models show that climate change has driven broad shifts in snail host range, whereas expansion of urban and peri-urban areas has driven localized increases in habitat suitability. Elucidating change in Biomphalaria distribution-while accounting for non-linearities that are difficult to detect from local case studies-can help inform schistosomiasis control strategies.
Topics: Animals; Brazil; Schistosoma mansoni; Ecosystem; Biomphalaria; Urbanization; Climate Change; Schistosomiasis mansoni; Snails; Humans
PubMed: 38898012
DOI: 10.1038/s41467-024-48335-9 -
Memorias Do Instituto Oswaldo Cruz 2024The impact of Schistosoma mansoni infection over the immune response and the mechanisms involved in pathogenesis are not yet completely understood.
BACKGROUND
The impact of Schistosoma mansoni infection over the immune response and the mechanisms involved in pathogenesis are not yet completely understood.
OBJECTIVES
This study aimed to evaluate the expression of innate immune receptors in three distinct mouse lineages (BALB/c, C57BL/6 and Swiss) during experimental S. mansoni infection with LE strain.
METHODS
The parasite burden, intestinal tissue oogram and presence of hepatic granulomas were evaluated at 7- and 12-weeks post infection (wpi). The mRNA expression for innate Toll-like receptors, Nod-like receptors, their adaptor molecules, and cytokines were determined at 2, 7 and 12 wpi in the hepatic tissue by real-time quantitative polymerase chain reaction (qPCR).
FINDINGS
Swiss mice showed 100% of survival, had lower parasite burden and intestinal eggs, while infected BALB/c and C57BL/6 presented 80% and 90% of survival, respectively, higher parasite burden and intestinal eggs. The three mouse lineages displayed distinct patterns in the expression of innate immune receptors, their adaptor molecules and cytokines, at 2 and 7 wpi.
MAIN CONCLUSIONS
Our results suggest that the pathogenesis of S. mansoni infection is related to a dynamic early activation of innate immunity receptors and cytokines important for the control of developing worms.
Topics: Animals; Schistosomiasis mansoni; Immunity, Innate; Mice, Inbred BALB C; Mice, Inbred C57BL; Cytokines; Mice; Schistosoma mansoni; Disease Models, Animal; Female; Toll-Like Receptors; Real-Time Polymerase Chain Reaction; Parasite Egg Count; Male; RNA, Messenger; Receptors, Immunologic
PubMed: 38896633
DOI: 10.1590/0074-02760240013 -
International Journal of Molecular... May 2024Flatworms are known for their remarkable regenerative ability, one which depends on totipotent cells known as germinative cells in cestodes. Depletion of germinative...
Flatworms are known for their remarkable regenerative ability, one which depends on totipotent cells known as germinative cells in cestodes. Depletion of germinative cells with hydroxyurea (HU) affects the regeneration of the parasite. Here, we studied the reduction and recovery of germinative cells in cysticerci after HU treatment (25 mM and 40 mM of HU for 6 days) through in vitro assays. Viability and morphological changes were evaluated. The recovery of cysticerci's mobility and morphology was evaluated at 3 and 6 days, after 6 days of treatment. The number of proliferative cells was evaluated using EdU. Our results show morphological changes in the size, shape, and number of evaginated cysticerci at the 40 mM dose. The mobility of cysticerci was lower after 6 days of HU treatment at both concentrations. On days 3 and 6 of recovery after 25 mM of HU treatment, a partial recovery of the proliferative cells was observed. Proteomic and Gene Ontology analyses identified modifications in protein groups related to DNA binding, DNA damage, glycolytic enzymes, cytoskeleton, skeletal muscle, and RNA binding.
Topics: Hydroxyurea; Animals; Cell Proliferation; Taenia; Proteomics; Helminth Proteins; Proteome; Cysticercus
PubMed: 38892261
DOI: 10.3390/ijms25116061 -
Animals : An Open Access Journal From... May 2024Monogeneans are flatworm parasites that infest fish gills primarily but can also infect various other vertebrates, including amphibians, aquatic reptiles, mammals like... (Review)
Review
Monogeneans are flatworm parasites that infest fish gills primarily but can also infect various other vertebrates, including amphibians, aquatic reptiles, mammals like hippos, and occasionally invertebrates like copepods, isopods, and cephalopods. Despite their remarkable diversity, our knowledge of monogenean parasites in Peru remains significantly limited, resulting in substantial gaps in our comprehension of their taxonomic identities, host associations, and geographic distribution. To address these knowledge deficits, we present an extensively curated checklist of monogeneans associated with aquatic vertebrates in Peru. This comprehensive compilation is derived from meticulous literature surveys, the examination of specimens deposited in both international and national collections, and the inclusion of additional freshly collected specimens. The checklist offers a thorough repository of data encompassing the diversity, host associations, and geographical distribution of these parasites. Taxonomic discrepancies are addressed through a critical review of the existing literature, supplemented by the direct examination of specimens, including type or voucher specimens, deposited within scientific collections. Additionally, we provide data on the DNA sequences of individual taxa. The compiled list comprises records of 358 monogenean species, including 270 valid species and 88 taxa identified at the family or generic level, all reported across 145 host species in Peru. Predominantly, these parasitic species exhibit associations within fish, with 335 infecting teleosts and 20 affecting chondrichthyans. Three monogenean species have been documented as infecting amphibians, namely , sp. and . Among the monogeneans reported, 141 were found in marine environments and 214 in freshwater environments. The most diverse families were Dactylogyridae and Diplectanidae, comprising 217 and 24 species, respectively. The hosts that harbored the highest number of monogeneans were (with 23 species), followed by (13 spp.) and (11 spp.). We detected many species that do not have any material deposited in a scientific collection due to the loss or deactivation of the collection. These findings represent only a fraction of the potential diversity, considering the wide variety of aquatic vertebrate hosts inhabiting the tropical and subtropical regions of Peru.
PubMed: 38891589
DOI: 10.3390/ani14111542 -
BMJ Open Jun 2024Urogenital schistosomiasis (UGS) caused by is endemic in Southern Tanzania. The disease has significant implications for both socioeconomic and public health. Because...
BACKGROUND
Urogenital schistosomiasis (UGS) caused by is endemic in Southern Tanzania. The disease has significant implications for both socioeconomic and public health. Because infections with usually peak in childhood, the majority of studies have concentrated on school-aged children leaving other groups such as males which might be continuous reservoir of infection transmission. However, despite its chronic consequences in the male population, the disease has received insufficient attention, especially in sub-Saharan Africa. This study was conducted to describe the previous and current schistosomiasis status among adult males living in high-endemic areas of southern Tanzania DESIGN, SETTING AND PARTICIPANTS: A descriptive cross-sectional study was employed to gather data on the prevalence of UGS among adult men residing at schistosomiasis endemic in the Mtama District Council. Quantitative methods of data collection which included questionnaire and laboratory procedures were used.
RESULTS
Out of 245 participants, macrohaematuria and microhaematuria were found in 12 (4.9%, 95% CI 2.4% to 7.8%) and 66 (26.9%, 95% CI 21.6% to 32.7%) participants, respectively. ova were recovered from the urine samples of 54 (22.0%, 95% CI 16.7% to 27.3%) participants. The median intensity of infection was 20 eggs per 10 mL of urine ranging from 1 to 201 eggs per 10 mL of urine (IQR) 60.5). Out of 245 participants 33 (13.5% 95% CI 9.0% to 17.6%) had light intensity of infection and 21 (38.9%, 95% CI; 25.0% to 52.5%) had heavy intensity of infection. Overall, the prevalence of heavy intensity of infection was 8.6% (95% CI 4.9% to 12.6%). The prevalence and intensity of UGS varied significantly by age, marital status and village of residence.
CONCLUSION
This study sheds light on the prevalence of UGS among adult males in endemic areas of southern Tanzania. The results highlight the urgent need for comprehensive intervention strategies to address the burden of the disease.
Topics: Humans; Male; Tanzania; Cross-Sectional Studies; Schistosomiasis haematobia; Adult; Prevalence; Young Adult; Schistosoma haematobium; Endemic Diseases; Middle Aged; Animals; Adolescent; Hematuria
PubMed: 38889945
DOI: 10.1136/bmjopen-2023-079690 -
Proceedings of the National Academy of... Jun 2024Germ cells are regulated by local microenvironments (niches), which secrete instructive cues. Conserved developmental signaling molecules act as niche-derived regulatory...
Germ cells are regulated by local microenvironments (niches), which secrete instructive cues. Conserved developmental signaling molecules act as niche-derived regulatory factors, yet other types of niche signals remain to be identified. Single-cell RNA-sequencing of sexual planarians revealed niche cells expressing a nonribosomal peptide synthetase (). Inhibiting led to loss of female reproductive organs and testis hyperplasia. Mass spectrometry detected the dipeptide β-alanyl-tryptamine (BATT), which is associated with reproductive system development and requires and a monoamine-transmitter-synthetic enzyme Aromatic L-amino acid decarboxylase (AADC) for its production. Exogenous BATT rescued the reproductive defects after or inhibition, restoring fertility. Thus, a nonribosomal, monoamine-derived peptide provided by niche cells acts as a critical signal to trigger planarian reproductive development. These findings reveal an unexpected function for monoamines in niche-germ cell signaling. Furthermore, given the recently reported role for BATT as a male-derived factor required for reproductive maturation of female schistosomes, these results have important implications for the evolution of parasitic flatworms and suggest a potential role for nonribosomal peptides as signaling molecules in other organisms.
Topics: Animals; Planarians; Female; Male; Peptide Synthases; Sexual Development; Peptides; Reproduction; Signal Transduction
PubMed: 38889152
DOI: 10.1073/pnas.2321349121 -
PeerJ 2024Schistosomiasis is a neglected tropical disease and an important parasite negatively impacting socio-economic factors. Ethiopia's Federal Ministry of Health targeted the...
BACKGROUND
Schistosomiasis is a neglected tropical disease and an important parasite negatively impacting socio-economic factors. Ethiopia's Federal Ministry of Health targeted the elimination of schistosomiasis infection in school-aged children by 2020. However, still affects approximately 12.3 million school-aged children in Ethiopia. Although the study was conducted in some regions of the country, previous studies were conducted on urban school children and were limited to the burden of infection. Overall, there is a lack of information about schistosomiasis in eastern Ethiopia, particularly among school children. Therefore, this study aimed to assess the prevalence and factors associated with infection among primary school children in Kersa district, Eastern Ethiopia.
METHODS
A cross-sectional study was conducted among 419 school children using systematic random sampling from April 10 to May 09, 2019. The stool samples were collected and examined using the Keto-Katz method. A structured and pretested questionnaire was used to collect data from participants. Data were entered using Epi-Data version 3.1 and analysed using SPSS version 24. A bivariable and multivariable logistic regression analyses were used to identify factors associated with infection. P-value < 0.05 and adjusted odds ratio (AOR) (95% confidence interval (CI)) were used to identify statistically significant associations.
RESULTS
This study's overall prevalence of was 19.4% (95% CI [16-23]). Absence of the latrines in household (AOR = 2.35, 95% CI [1.25-4.38]), swimming in the river (AOR = 2.82, 95% CI [1.33-5.88]), unprotected water sources (AOR = 3.5, 95% CI [1.72-7.10]), irregular shoe wearing habits (AOR = 2.81, 95% CI [1.51-5.23]), and water contact during cross of river (AOR = 2.192; 95% CI [1.113-4.318]) were factors independently associated with infection.
CONCLUSION
infection remains a public health problem in the study area. Using a latrine in each household, using protected water, wearing shoes regularly, and reducing water contact were necessary to control infection.
Topics: Humans; Ethiopia; Schistosomiasis mansoni; Child; Male; Prevalence; Female; Cross-Sectional Studies; Animals; Schistosoma mansoni; Risk Factors; Feces; Adolescent; Schools
PubMed: 38887618
DOI: 10.7717/peerj.17439