201 research outputs found
Genetic survey of alveolar and cystic echinococcoses in Romania: first molecular evidence of Echinococcus multilocularis in humans in the country
Cystic echinococcosis (CE) and alveolar echinococcosis (AE) are considered as one of the most
important zoonotic diseases in Romania, where they are subject to mandatory reporting. To obtain
more knowledge about the genetic diversity of Echinococcus causative agents of these diseases, 11
isolates from humans and ungulate intermediate hosts from the two regions of Romania were genotyped
using mitochondrial markers. In clinical samples of fi ve patients from north-eastern Romania
(Iasi, Botosani, Vaslui counties), Echinococcus multilocularis was identifi ed as causal agent by cox1
sequence analysis. To the best of our knowledge this fi nding presents the fi rst molecular evidence
of E. multilocularis in humans from Romania. Only two cases of AE in patients were previously documented
in the country by serological methods. In our four patients the most widespread European
variant E5 of E. multilocularis was recorded, whereas in isolate from Vaslui county three nucleotide
substitutions were detected as compared to the most related E5 haplotype. One of these mutations
(411T/G) matched N1 and N2 haplotypes described previously from North America. In six CE samples
retrieved from western Romania (Caras-Severin and Timis counties), two human isolates were
diagnosed as Echinococcus canadensis G7, one as E. granulosus s.s. G1 and one as E. granulosus
s.s. G3 using atp6 and rrnS sequencing. In ungulates, the cattle isolate was allocated to E. granulosus
s.s. G1 and pig isolate to E. canadensis G7. The two G7 fi ndings in humans reinforced the
recent view that G7 was underestimated as compared to the E. granulosus s.s. regarding human
CE threat that can be further employed for identifying sources of infections and establishing suitable
preventive measures
A molecular survey of Echinococcus granulosus sensu lato in central-eastern Europe
Central-eastern Europe is an endemic region for cystic echinococcosis where multiple species of intermediate hosts are commonly infected with
Echinococcus granulosus sensu lato tapeworms of major medical and veterinary importance. Investigations of the genetic variation of 25 Echinococcus isolates from five countries (Slovakia, Romania, Ukraine, Hungary, Poland) were undertaken using three mitochondrial DNA markers. The 18 isolates from pigs derived from Slovakia and Ukraine and the four human isolates from Slovakia, Poland and Ukraine were identified as E. canadensis G7,
whereas the three human isolates from Romania and Hungary were classified as E. granulosus sensu stricto G1. This study reports the first confirmed human case of E. granulosus s.s. in Hungary. The haplotype G7A with two polymorphic sites relative to the most common regional variant of E. canadensis G7 was recorded in both pigs from Ukarine and in a single pig isolate from Slovakia. The results of this study support the circumstantial
evidence that E. canadensis G7 with low infectivity for humans is highly prevalent in the northern parts of the region (Poland, Slovakia, forest-steppe zone of Ukraine),while infections with E. granulosus s.s. which are highly infectious for humans are more commonly encountered in Romania and Hungary
Fitness of the marine parasitic nematode Anisakis simplex s. str. in temperate waters of the NE Atlantic
In temperate waters of the NE Atlantic, third-stage larvae of Anisakis simplex sensu stricto collected from 3 paratenic host species were identified by restriction fragment length polymorphisms. The condition of wild larval infrapopulations was assessed by examining morphometric and growth characteristics. The differentiation patterns and the excretory/secretory products of larvae grown in Vitro were also examined. An extensive morphometric, growth and differentiation variability was found between parasite larvae collected from different paratenic host sources. Nematode infrapopulation larvae from the squid comprise those smaller individuals with the lowest values of survival rates and moult success. It may be then concluded that the fitness of A. simplex s. str. larvae is not the best possible in the squid, which impaired the competitiveness of the parasite and its chances of developing into an adult. This suggests that the microenvironments impaired by the paratenic host may provide larval infrapopulations with unique ecological factors probably influencing its recruitment to the final host populations
Treatment failure in osteoporosis: who will experience a new Fracture? TAILOR a retrospective study.
Osteoporosis treatments reduce fracture risk but cannot fully eliminate it, and the concept of treatment failure (TF) or inadequate clinical response (ICR) remains debated.
The TAILOR study aims to assess the prevalence of ICR and TF in osteoporotic women undergoing active drug treatment for postmenopausal osteoporosis.
TAILOR is a retrospective study conducted in an Italian outpatient service. We included 415 patients with at least 12 months of treatment and up to 10 years, examining clinical characteristics predicting TF and ICR. TF was defined as the occurrence of two fragility fractures while on treatment or one fracture plus lack of variation BMD and ICR as the occurrence of a new osteoporotic fracture in treated patients according to previous literature.
Seventy-two patients experienced fractures during the follow-up, of those, 26 (36%) were classified as TF. The clinical characteristics of patients with fractures were similar to those without, except for a longer postmenopausal period and lower lumbar spine bone mineral density (BMD). Postmenopausal period was significantly longer in TF compared to ICR patients. However, no significant differences were found in baseline fractures, prescribed treatments, or fracture-free survival curves with age, postmenopausal period, BMD, and previous treatments. The clinical follow-up was longer in ICR and TF patients.
TAILOR shows a higher prevalence of ICR and TF (17.3%) compared to randomized controlled trials and real-world data, with 36% of fractures during follow-up classified as TF. Clinician decisions often led to changes in antiosteoporosis treatment, particularly in TF cases, though TF diagnosis was rarely cited explicitly in medical records.
TAILOR emphasizes that common clinical factors do not reliably predict ICR and TF. The findings highlight the complexity of determining an algorithm for the best treatment approach to prevent TF and ICR
Dopamine neuronal loss contributes to memory and reward dysfunction in a model of Alzheimer's disease
Alterations of the dopaminergic (DAergic) system are frequently reported in Alzheimer’s disease (AD) patients and are commonly linked to cognitive and non-cognitive symptoms. However, the cause of DAergic system dysfunction in AD remains to be elucidated. We investigated alterations of the midbrain DAergic system in the Tg2576 mouse model of AD, overexpressing a mutated human amyloid precursor protein (APPswe). Here, we found an age-dependent DAergic neuron loss in the ventral tegmental area (VTA) at pre-plaque stages, although substantia nigra pars compacta (SNpc) DAergic neurons were intact. The selective VTA DAergic neuron degeneration results in lower DA outflow in the hippocampus and nucleus accumbens (NAc) shell. The progression of DAergic cell death correlates with impairments in CA1 synaptic plasticity, memory performance and food reward processing. We conclude that in this mouse model of AD, degeneration of VTA DAergic neurons at pre-plaque stages contributes to memory deficits and dysfunction of reward processing
Molecular characterization of larval anisakid nematodes from marine fishes of Madeira by a PCR-based approach, with evidence for a new species
One-hundred and fifteen anisakid larvae from 3 different fish hosts, Aphanopus carbo, Scomber japonicus, and Trachurus picturatus, caught in Madeiran waters, were identified by PCR-RFLP. Three distinct species were identified in A. carbo, namely Anisakis simplex sensu stricto, Anisakis pegreffii, and Anisakis ziphidarum; 5 in S. japonicus, i.e., A. simplex s.s., A. pegreffii, Anisakis physeteris, Anisakis typica, and A. ziphidarum; and 3 in T. picturatus, i.e., A. simplex s.s., A. pegreffii, and A. typica. Anisakis simplex s.s. was the most frequent species in both A. carbo and S. japonicus (54% and 23.5%, respectively). Anisakis pegreffii and A. physeteris occurred with a frequency of 20.6% in S. japonicus, whereas in T. picturatus the most frequent species was A. typica (41.9%), followed by A. simplex s.s. (32.3%). Furthermore, A. carbo and S. japonicus were infected by an apparently undescribed taxon, provisionally named Anisakis sp. A. Based on estimations of the genetic distance, this new taxon seems to be more similar to A. ziphidarum (0.0335) than to other species of the genus
Recommended from our members
Comparative Transcriptomics Reveals Clues for Differences in Pathogenicity between Hysterothylacium aduncum, Anisakis simplex sensu stricto and Anisakis pegreffii.
Ascaridoid nematodes are widespread in marine fishes. Despite their major socioeconomic importance, mechanisms associated to the fish-borne zoonotic disease anisakiasis are still obscure. RNA-Seq and de-novo assembly were herein applied to RNA extracted from larvae and dissected pharynx of Hysterothylacium aduncum (HA), a non-pathogenic nematode. Assembled transcripts in HA were annotated and compared to the transcriptomes of the zoonotic species Anisakis simplex sensu stricto (AS) and Anisakis pegreffii (AP). Approximately 60,000,000 single-end reads were generated for HA, AS and AP. Transcripts in HA encoded for 30,254 putative peptides while AS and AP encoded for 20,574 and 20,840 putative peptides, respectively. Differential gene expression analyses yielded 471, 612 and 526 transcripts up regulated in the pharynx of HA, AS and AP. The transcriptomes of larvae and pharynx of HA were enriched in transcripts encoding collagen, peptidases, ribosomal proteins and in heat-shock motifs. Transcripts encoding proteolytic enzymes, anesthetics, inhibitors of primary hemostasis and virulence factors, anticoagulants and immunomodulatory peptides were up-regulated in AS and AP pharynx. This study represents the first transcriptomic characterization of a marine parasitic nematode commonly recovered in fish and probably of negligible concern for public health
Sensitive Detection and Quantification of Anisakid Parasite Residues in Food Products
Anisakids are nematodes whose larval stages are often present in fish, molluscs, and crustaceans. Members of the family Anisakidae belonging to the genera Anisakis and Pseudoterranova are implicated in human infections caused by the consumption of raw or undercooked fish. Adequate cooking will kill anisakid larvae, however, killed or inactivated larvae can still cause sensitization and immunoglobulin E-dependent hypersensitivity in human. This work describes the development of DNA-based tests to detect and quantify the presence of Anisakis spp. and Pseudoterranova spp. larvae in fish and fish-derived products, including fish fillets, surimi, fish sticks, canned fish, and baby food. Primers and TaqMan MGB probes recognizing only Anisakis spp. and Pseudoterranova spp. were designed on the first internal transcribed spacer 1 regions of rDNA for a real-time polymerase chain reaction assay. A commercial probe for 18S rDNA was used to detect and quantify the total eukaryotic DNA of the samples. The specificity and sensitivity of the assays were tested using reference samples prepared from mixtures made of Anisakis larvae in different quantity of codfish, and subsequent dilutions. Studies were performed to assess the ability of the test to detect and quantify anisakids in various products. Results showed that this test is able to detect anisakid DNA contained in a proportion of 1:10(5) in 1 ng of total DNA. The high prevalence of anisakids reported in main fishery species was confirmed by frequently detecting anisakids DNA in fish muscle and fish-derived products. A partial correlation was found between the number of larvae present in the viscera and the level of contamination of fish fillets. In conclusion, this molecular test is useful to detect the presence of Anisakis spp. and Pseudoterranova spp. in fish and fish-derived products and to quantify the level of contamination along the food chain, with potential applications for fish farms, fish markets, and food producers
SSCP-based identification of members within the Pseudoterranova decipiens complex (Nematoda : Ascaridoidea : Anisakidae) using genetic markers in the internal transcribed spacers of ribosomal DNA
The anisakid nematodes morphologically corresponding with Pseudoterranova decipiens sensu lato (s.l.) (Krabbe, 1878) from different seal or sea lion hosts and geographical origins, previously identified as Pseudoterranova krabbei, P. decipiens (s.s.), P. bulbosa, P. azarasi and P. cattani by multilocus enzyme electrophoresis, were characterized using a DNA approach. Also a population of P. decipiens (s.l.) from Chaenocephalus aceratus, the blackfin icefish, from Antarctica and another from Osmerus eperlanus, the European smelt, from Germany were included in the study. The first (ITS-1) and second (ITS-2) internal transcribed spacers (ITS) of ribosomal DNA (rDNA) were amplified by PCR from individual nematodes and analysed by single-strand conformation polymorphism (SSCP), followed by selective sequencing. While no variation in single-stranded ITS-1 and ITS-2 profiles was detected among samples representing each of the species or populations (with the exception of slight microheterogeneity), SSCP analysis of the ITS-2 amplicons allowed the unequivocal differentiation of all of the 5 sibling species of P. decipiens (s.l.) examined, which was supported by sequence differences in ITS rDNA. Samples representing the P. decipiens (s.l.) population from O. eperlanus had the same SSCP profile as those of P. decipiens (s.s.), which was supported by a lack of nucleotide difference in the ITS between them, suggesting that the former represented P. decipiens (s.s.). Based on SSCP results and ITS sequence data, P. decipiens (s.l.) from C. aceratus was genetically most distinct with respect to all other members of Pseudoterranova examined, which indicated that it may represent P. decipiens E (based on geographical origin) or a distinct species. These findings and the molecular approach taken should have important implications for studying the life-cycles, transmission patterns, epidemiology and population genetics of these anisakid nematodes, and the diagnosis of their infections
Genetic variability of Haemonchus contortus (Nematoda: Trichostrongyloidea) in alpine ruminant host species
Genetic variability of the ovine parasite Haemonchus contortus from the Alpine area was investigated using mitochondrial DNA (nd4 gene), internal transcribed spacers 1 and 2 and microsatellites, in order to assess whether cross-transmission between domestic and wild ruminants occurs. The dataset was composed of 78 individual adult male H. contortus collected from chamois (Rupicapra r. rupicapra), roe deer (Capreolus capreolus), alpine ibex (Capra ibex ibex), domestic goat (Capra hircus) and sheep (Ovis aries) from different alpine areas. The data obtained show low host specificity and high genetic variation within H. contortus populations. The analyses indicate the presence of two mitochondrial haplotype clusters among host species and the absence of cryptic parasite species, confirming H. contortus as a generalist nematode and suggesting that parasite transmission between populations of domestic and wild ruminants normally occurs
- …
