COX-1 Research Articles

Diversity of Cytauxzoon spp. (Piroplasmida: Theileriidae) in Wild Felids from Brazil and Argentina

Domestic and wild felids are frequently parasitized by apicomplexan protozoa in the genus Cytauxzoon. Expanding species diversity has recently been described within this genus, with potential implications for epidemiology and pathogenesis. In light of these findings, this study assessed the genetic diversity of Cytauxzoon spp. in wild felids (n = 66) from different eco-regions of Brazil and Argentina. Of the 66 blood samples analyzed, 53 (80.3%) were 18S rRNA gene PCR-positive for Cytauxzoon spp., including 43 jaguars (Panthera onca) and 10 ocelots (Leopardus pardalis). Panthera onca specimens (100%, 43/43) were most frequently infected, followed by Leopardus pardalis (76.9%; 10/13). Cytauxzoon spp. were not detected in Leopardus braccatus (n = 1) or Puma concolor (n = 9). Phylogenetic analyses of fragments of the 18S rRNA, cytB, and cox-1 gene sequences from jaguars were closely related to Cytauxzoon felis. In contrast, sequences from ocelots were more closely associated with Cytauxzoon brasiliensis. Distance and haplotype analysis further confirmed the circulation of at least two distinct genovariants of C. felis among jaguars, as evidenced by their close positioning and low genetic divergence (0–0.14% for 18S rRNA, 0.37–0.56% for cytB, and 0.08–0.74% for cox-1). Additionally, sequence data from ocelots suggested that multiple genovariants of C. brasiliensis are circulating among these cats in different Brazilian eco-regions. Our study provides evidence of two distinct Cytauxzoon organisms parasitizing free-ranging and captive jaguars and ocelots, respectively, in Brazil and Argentina.

A Genome-Wide Analysis of Nuclear Mitochondrial DNA Sequences (NUMTs) in Chrysomelidae Species (Coleoptera)

Nuclear mitochondrial DNA sequences (NUMTs) are mitochondrial DNA fragments in the nuclear genome, and their unclear distribution in Chrysomelidae species hinders the selection of accurate molecular markers for species identification and phylogenetic analysis. Our study presents a genome-wide survey of NUMTs in 32 Chrysomelidae species. Filtering strategies based on sequence length and open reading frame (ORF) features were employed to identify mitochondrial protein-coding genes (PCGs) minimally affected by NUMTs. Phylogenetic relationships were inferred from both mitochondrial PCG datasets and a COX1 dataset containing NUMTs. Our results show that NUMTs are chromosomally specific, species-specific, and widely distributed. ATP8, COX1, ND1, and ND4 are identified as relatively reliable molecular markers. Phylogenetic analysis is influenced by NUMTs and other factors such as sequence type and saturation. A total of 66 independent COX1 gene nuclear integration events were estimated across 32 species, mostly from distinct mitochondrial lineages. These findings suggest that NUMTs reflect key evolutionary processes such as gene flow and mitochondrial lineage diversification. Their prevalence emphasizes the need for refined molecular markers in species identification and phylogenetic analysis, while also highlighting the importance of NUMTs in understanding mitochondrial DNA integration and their contribution to species’ evolutionary history.

Taenia asiatica: Mitochondrial signatures based analysis of an emerging public health threat in India.

Taenia asiatica is a zoonotic tapeworm, commonly known as Asian Taenia. It is an emerging sister species of T. saginata with pigs as intermediate hosts. The present study aimed at genetic characterization and population structure analysis of T. asiatica metacestodes in slaughtered pigs in Haryana, north India. In total, the vital organs of 253 slaughtered pigs were screened for the presence of T. asiatica metacestodes. The molecular identification and phylogenetics were performed targeting the mitochondrial NADH dehydrogenase subunit 1 (nad1) and cytochrome C oxidase subunit 1 (cox1) genes. The median-joining haplotype network and population structure analyses were performed with the sequences generated herein and GenBank-archived T. asiatica sequences for both mitochondrial signatures. Out of 253 pigs screened, the liver of only one animal showed the presence of T. asiatica metacestodes. The sequences generated herein exhibited 99.60% and 98.85% similarity to the GenBank-archived sequences of T. asiatica corresponding to the nad1 and cox1 genes, respectively. Overall, 2 and 6 haplotypes for the overall data set with low nucleotide (0.00399±0.00237 and 0.00095±0.00042) and low haplotype (0.400±0.237 and 0.131±0.054) diversities were recorded for the nad1 and cox1 genes, respectively. The negative values recorded for the neutrality indices exhibited deviations from neutrality and hence, propounded recent population expansion or purifying selection or selective sweep. The findings of the present study are of significant medical importance considering an emerging global public health threat of the neglected tapeworm T. asiatica.

Massive subcutaneous filariosis by Filaria martis in beech marten (Martes foina) in Italy.

The beech marten (Martes foina) is a small-size mustelid endangered according to the IUCN Red List. Despite the plethora of parasites potentially affecting its population decline, subcutaneous filarioids are occasionally reported in martens and their competent arthropod vectors are to date unknown. Therefore, from January 2023 to August 2024, this study investigated the presence of subcutaneous filarioids and ectoparasites of road-killed beech martens (n=7) from southwestern Italy. One marten (14.3%, 95% CI: 2.6-51.3) was massively infected with subcutaneous filarioids, i.e., 18 specimens (11 males and 7 females) in the dorso-posterior region, where mild redness and sloughing of skin were found. All the filarioids were identified as Filaria martis via morphology and Sanger sequencing of the cytochrome c oxidase subunit I (cox1) gene that revealed a single sequence type (GenBank accession number PQ034642) having 100% nucleotide identity with those available in the literature. The phylogenetic analysis displayed a bootstrap value of 100% between the cox1 sequences of F. martis of this study and those of beech martens from Italy and European minks from Spain. Haemolymph, gut, and salivary glands of the Ixodes ricinus ticks collected from the infected marten scored negative for F. martis larvae and DNA by dissection and PCR, respectively. This study reported for the first time F. martis subcutaneous filariosis in southwestern Italy, previously outlined only in northern and southeastern areas, indicating the circulation of this poorly investigated filarioid. Knowledge of the competent vectors involved in the biological cycle of F. martis requires further experimental studies.

Terrestrial Adaptation in Chelonoidis vicina as Revealed Based on Analysis of the Complete Mitochondrial Genome

Background/Objectives: Mitochondrial genomes are widely used in phylogenetics and evolutionary and ecological research. Methods: In this study, the newest mitochondrial genome of Chelonoidis vicina was assembled and annotated. The comparative mitochondrial genome and selection pressure analyses were used to examine the terrestrial adaptive evolution characteristics of C. vicina and other terrestrial reptiles. Results: The results reveal that the mitochondrial genome of the tortoise C. vicina is consistent with that of other tortoise species, comprising 13 protein-coding genes (PCGs), 2 rRNAs, 22 tRNAs, and 1 noncoding control region (CR). The analysis of selection pressure reveals the presence of positive selection sites in the COX2, COX3, Cytb, ND3, ND4, ND4L, ND5, and ND6 genes of terrestrial reptiles. Of these, the COX2 and ND3 genes exhibited faster evolutionary rates. The mitochondrial genome structure of C. vicina is consistent with that of different terrestrial reptiles. The positive selection sites of COX2 and ND3 in terrestrial reptiles are closely related to a change in mitochondrial energy metabolism, which is possibly related to terrestrial adaptability. Conclusions: The results of this study provide new insights into the adaptive evolution of C. vicina to terrestrial niches from a mitogenomic perspective, as well as genetic resources for the protection of C. vicina.

Antitumor Activity of Warbugia ugandensis: Methanolic Extracts and Gene Regulation in Colorectal Cancer

A promising approach to accelerating the development of innovative anti-cancer therapies involves the evaluation of natural plant compounds. In this study, we focused on examining the effects of Warbugia ugandensis (W. ugandensis) methanolic root and stem infusions on the activity of five target genes—COX-2, CASPS-9, Bcl-xL, Bcl2, and 5-LOX—using colorectal cancer (CRC) cell lines (Caco-2). The plant extracts were prepared for testing by dissolving them in dimethyl sulfoxide (DMSO) after undergoing a step-by-step extraction process. Caco-2 cells were then treated with different concentrations of the extracts, and RNA was extracted and purified for analysis. Our results demonstrated a dose-dependent relationship between the phytoconstituents of W. ugandensis and the overexpression of CASP9, along with the downregulation of COX-2, 5-LOX, Bcl-xL, and Bcl2 genes. This suggests that W. ugandensis acts as a potent natural inhibitor of CRC progression. Given the potential clinical benefits, we propose the use of W. ugandensis methanolic root and stem extracts as promising organic inhibitors for CRC tumorigenesis, with more in vitro studies warranted to validate and expand on our findings. Additionally, we recommend further studies to identify and characterize the specific metabolites in W. ugandensis that contribute to the modulation of pathways responsible for inhibiting CRC growth.

A survey of root-knot and false root-knot nematodes at commercial vegetable farms under protected cultivation in La Plata Green Belt, Argentina

Summary Root-knot and false root-knot nematodes, Meloidogyne spp. and Nacobbus spp., respectively, represent one of the most economically-impacting crop protection concerns at La Plata Green Belt (LPGB), Argentina. The aims of this paper were to determine the frequency and distribution of root-knot and false root-knot nematodes under protected cultivation and an update of the recorded area of LPGB. An exhaustive survey of these nematodes was carried out. A total of 75 samples, corresponding to an equivalent number of prospected areas, were taken. Eleven of the prospected squares (14.6% of the total) were free of galling nematodes; coincidently, these were areas recently incorporated into protected horticulture. The other remaining areas were positive for the presence of galling nematodes. Nacobbus spp. were found in 93.4% of the positive samples, whereas Meloidogyne spp. were found in 12.5%. In three out of 75 samples co-infestation by both Nacobbus and Meloidogyne was registered. Solanaceae and Amaranthaceae were the most frequent hosts for both genera of galling nematodes. Two populations of N. celatus from tomato and pepper, respectively, were identified by the mitochondrial gene CoxI. A first molecular analysis of M. arenaria for the LPGB is reported here.

PET Quantification in Healthy Humans of Cyclooxygenase-2, a Potential Biomarker of Neuroinflammation.

Cyclooxygenase-2 (COX-2) is present in a healthy brain at low densities but can be markedly upregulated by excitatory input and by inflammogens. This study evaluated the sensitivity of the PET radioligand [11C]-6-methoxy-2-(4-(methylsulfonyl)phenyl)-N-(thiophen-2-ylmethyl)pyrimidin-4-amine ([11C]MC1) to detect COX-2 density in a healthy human brain. Methods: The specificity of [11C]MC1 was confirmed using lipopolysaccharide-injected rats and transgenic mice expressing the human COX-2 gene, with 120-min baseline and blocked scans using COX-1 and COX-2 selective agents. Twenty-seven healthy participants were injected with [11C]MC1. Ten of these participants received 2 PET scans: a baseline study followed by blockade with celecoxib (600 mg orally), a preferential COX-2 inhibitor. Seventeen participants underwent test-retest imaging. All scans included concurrent arterial sampling. The tissue-to-plasma ratio at equilibrium (i.e., total distribution volume) was determined using a 2-tissue compartment model (2TCM). Results: In humanized transgenic COX-2 mice, 70%-90% of [11C]MC1 brain uptake was blocked by nonradioactive MC1 and celecoxib (a COX-2 selective inhibitor) but not by PS13 (a COX-1 selective inhibitor), thereby confirming specific binding to human COX-2. Radioactivity in the human brain peaked at a concentration of about 4.0 SUV, indicating good passage through the blood-brain barrier. Values for the total distribution volume achieved stability after 80 min, indicating no radiometabolite contamination. Celecoxib reduced radioligand binding in neocortical areas by 25% but had little or no effect in subcortical regions and the cerebellum, which correlated with COX-2 messenger RNA expression levels. Binding site occupancy by celecoxib was virtually complete, as determined by the Lassen plots. Test-retest reliability was moderate (intraclass correlation coefficient, 0.65) but had relatively large variability (absolute retest variability, 20%). Reference tissue methods yielded results comparable to those of 2TCM but reduced retest variability by up to 75% and reduced intersubject variability (coefficient of variation) by about half. Thus, compared with 2TCM, which requires arterial blood, the reference tissue method is expected to significantly reduce the sample sizes required to detect statistically significant differences between groups. Conclusion: [11C]MC1 has adequate sensitivity to measure the low density of COX-2 in a healthy human brain, suggesting it can also quantify the COX-2 elevations expected in human disorders associated with neuroinflammation.

Clonorchis sinensis and Echinostoma hortense detected by endoscopy and molecular characterization: two case reports and update on diagnosis

Clonorchis sinensis (C. sinensis) and Echinostoma hortense (E. Hortense) infections represent significant food-borne zoonotic parasitic diseases. C. sinensis stands as the primary parasite underlying cholangitis, cholelithiasis, and even cholangiocarcinoma, whereas E. Hortense parasitizes the duodenum. Unfortunately, the non-specific clinical presentations of these two trematodes frequently mislead clinicians, resulting in overlooks or misdiagnoses, and consequently, inadequate treatment. We diagnosed digestive system trematodes through endoscopic observation and molecular methods. Herein, we present a case where C. sinensis was definitively diagnosed through direct observation under duodenoscopy. For the first time, we captured the entire migratory process of the parasite from the common bile duct into the intestinal lumen. In another case, multiple active trematodes were detected on the duodenal wall under duodenoscopy, subsequently extracted using endoscopic forceps. Based on the morphology of the worms and their eggs, an initial diagnosis of Echinostoma was made. To confirm the species, we designed primers targeting the ribosomal ITS (internal transcribed spacer) and mitochondrial COX-1 (cyclooxygenase-1) genes, followed by PCR amplification and sequencing. The results conclusively matched the sequence of E. Hortense, verifying our final diagnosis. Our proposed approach, integrating endoscopy with molecular characteristics, offers novel strategies for diagnosing trematode infections. This methodology represents a significant advancement in the field, enhancing the accuracy and timeliness of treatment interventions.

Comprehensive analysis of 111 Pleuronectiformes mitochondrial genomes: insights into structure, conservation, variation and evolution

BackgroundPleuronectiformes, also known as flatfish, are important model and economic animals. However, a comprehensive genome survey of their important organelles, mitochondria, has been limited. Therefore, we aim to analyze the genomic structure, codon preference, nucleotide diversity, selective pressure and repeat sequences, as well as reconstruct the phylogenetic relationship using the mitochondrial genomes of 111 flatfish species.ResultsOur analysis revealed a conserved gene content of protein-coding genes and rRNA genes, but varying numbers of tRNA genes and control regions across species. Various gene rearrangements were found in flatfish species, especially for the rearrangement of nad5-nad6-cytb block in Samaridae family, the swapping rearrangement of nad6 and cytb gene in Bothidae family, as well as the control region translocation and tRNA-Gln gene inversion in the subfamily Cynoglossinae, suggesting their unique evolutionary history and/or functional benefit. Codon usage showed obvious biases, with adenine being the most frequent nucleotide at the third codon position. Nucleotide diversity and selective pressure analysis suggested that different protein-coding genes underwent varying degrees of evolutionary pressure, with cytb and cox genes being the most conserved ones. Phylogenetic analysis using both whole mitogenome information and concatenated independently aligned protein-coding genes largely mirrored the taxonomic classification of the species, but showed different phylogeny. The identification of simple sequence repeats and various long repetitive sequences provided additional complexity of genome organization and offered markers for evolutionary studies and breeding practices.ConclusionsThis study represents a significant step forward in our comprehension of the flatfish mitochondrial genomes, providing valuable insights into the structure, conservation and variation within flatfish mitogenomes, with implications for understanding their evolutionary history, functional genomics and fisheries management. Future research can delve deeper into conservation biology, evolutionary biology and functional usages of variations.

Anti-inflammatory Effects of the Fucoidan from Sea Cucumber Apostichopus japonicus.

Fucoidan from Apostichopus japonicus (Aj-FUC) has shown anti-inflammatory activity, whereas its mechanism was not explicated. This study investigated the anti-inflammatory potential and mechanism of the fucoidan from green and purple A. japonicus (G-FUC and P-FUC) in lipopolysaccharide (LPS)-treated RAW264.7 cells. Results showed that Aj-FUCs at 25-400µg/mL had no toxicity to cells after 24h stimulation and promoted cell phagocytic activity. ELISA results indicated that Aj-FUC reduced the nitric oxide (NO), tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), and IL-6 levels and increased IL-10 level. The Aj-FUC suppressed transcription of inflammatory-related genes (tnf-α, il-1β, il-6, nlrp3, inos, cox-2, tlr4, trif, and nf-κb) in LPS-treated RAW264.7 cells, among which G-FUC had stronger anti-inflammatory effects. Moreover, Aj-FUC upregulated the mRNA expression of autophagic genes (beclin1, lc3II, and lamp2). The immunoblotting and immunofluorescence analyses of Beclin-1 and LC3II supported that Aj-FUC enhanced autophagy activity. After autophagy inhibited by 3-methyladenine, the mRNA expressions of tnf-α, il-6, il-1β, and nlrp3 were significantly upregulated in LPS-induced cells treated with Aj-FUC, suggesting the suppressed inflammation by Aj-FUC mediated via autophagy. Summarily, the present study demonstrated that Aj-FUC showed anti-inflammatory effects by elevating autophagy activity in LPS-induced macrophages.

Complex species structure of Lecithaster salmonis (Digenea: Lecithasteridae), a fish parasite in the Arctic and Pacific Northwest.

Studying complexes of cryptic or pseudocryptic species opens new horizons for the understanding of speciation processes, an important yet vague issue for the digeneans. We investigated a hemiuroidean trematode Lecithaster salmonis across a wide geographic range including the northern European seas (White, Barents, and Pechora), East Siberian Sea, and the Pacific Northwest (Sea of Okhotsk and Sea of Japan). The goals were to explore the genetic diversity within L. salmonis through mitochondrial (cox1 and nad5 genes) and ribosomal (ITS1, ITS2, 28S rDNA) marker sequences, to study morphometry of maritae, and to revise the life cycle data. Mitochondrial markers showed that L. salmonis is likely divided into six lineages (referred to as operational taxonomic units, OTUs), which often occur in sympatry, sometimes in a single host specimen. Variation in rDNA was not consistent with that in the mitochondrial markers. Morphometric analysis of maritae was performed for four out of six OTUs; it showed that some OTUs had significant differences from the others, but some did not. The effect of host species on the morphometric characteristics cannot be excluded. Intramolluscan stages were identified for two OTUs; they differed clearly by the structure of cercariae and also by the species of the first intermediate host. The case of L. salmonis is instructive in how different criteria for species delimitation can contradict each other. We regard this as a sign of recent or ongoing speciation and suggest using the name Lecithaster cf. salmonis. The most promising criteria to differentiate genetic lineages within L. cf. salmonis are first intermediate hosts and morphological characteristics of the cercariae: shape of the delivery tube and caudal cyst, and length of the filamentous appendage.

The North American tapeworm Ophiotaenia saphena (Cestoda: Proteocephalidae) in frogs (Ranidae) of Europe: introduction via the American bullfrog (Lithobates catesbeianus)?

Frogs (Amphibia: Ranidae) in Europe have been intensively studied for parasites for decades, but no proteocephalid tapeworms (Cestoda) have been found. Recently, tapeworms of the genus Ophiotaenia La Rue, 1911 were found in frogs of the family Ranidae (Pelophylax spp.) in Greece and Romania. These are the first proteocephalids found in anurans of the continental Palaearctic. Despite slight morphological differences between the tapeworms from Greece and Romania, all tapeworms were almost identical in the 28S rRNA and even cox1 gene sequences, suggesting that they belong to a single species. Furthermore, the tapeworms from Europe are genetically indistinguishable from O. saphena Osler, 1931, a parasite of the green frog Lithobates clamitans (Latreille) and the American bullfrog L. catesbeianus (Shaw) (Ranidae) in North America. The striking genetic and morphological similarity of the present specimens to O. saphena in its native range suggests that this may be a recent introduction of this species to Europe and its switch to local hosts (parasite spillover). The documented introductions of bullfrogs into Europe further support the hypothesis of a very recent co-introduction of the non-native host species with its parasite. Although the first introductions of bullfrogs were restricted to western and central Europe, the lack of previous records of proteocephalid tapeworms in European ranids makes it difficult to trace the distribution of this North American species in the Balkan Peninsula.

Genetic diversity and intercontinental dispersal of temperate and subarctic populations of Dibothriocephalus dendriticus (Cestoda; Diphyllobothriidea), a causative agent of dibothriocephalosis.

The diphyllobothriid tapeworm Dibothriocephalus dendriticus, one of the causative agents of the fish-borne zoonosis dibothriocephalosis, is mainly distributed in the Arctic/subarctic and temperate zones of the Northern Hemisphere (Europe, North America, and Asia), but also in the southern cone region of South America (Patagonia). The genetic structure and gene flow among 589 individuals of D. dendriticus, representing 20 populations, were studied using the mitochondrial cox1 gene as the first choice marker and 10 polymorphic nuclear microsatellite loci as a dominant molecular tool. The haplotype network of 30 cox1 haplotypes and Principal Coordinate Analysis/Structure analysis based on microsatellite data revealed close genetic relationships among populations within continents, namely northern and northwestern Europe (Norway, Finland, and UK/Scotland), North America (USA/Alaska, USA/Oregon, and Greenland), and South America (Argentina and Chile). The population from Iceland, located on the Mid-Atlantic Ridge between North America and Europe, was related to both Europe and North America. The mixed Nearctic and Palaearctic origin of D. dendriticus in Iceland was confirmed by a coalescent-based analysis of the microsatellite loci (in Migrate software). The most likely scenarios suggested that the Icelandic population is a genetic admixture of tapeworms from northwestern Europe and USA/Alaska. These findings corresponded with the distribution and migratory routes of piscivorous birds of the family Laridae, the main definitive hosts of D. dendriticus. The origin of an apparently non-native population of D. dendriticus in Patagonia was investigated in detail. The two most plausible hypotheses based on Migrate analysis represented different scenarios. One of them points to a European origin of the Patagonian population, the other to a North American origin. Future research with more extensive and a geographically broader sampling set is recommended to trace dispersal routes of D. dendriticus in Patagonia.

A New Species of Anthocotyle (Polyopisthocotyla: Discocotylidae) from the Gills of the European Hake Merluccius merluccius (Teleostei, Merlucciidae) with a Revision of the Composition of the Genus

This study revisits the taxonomy of Anthocotyle merluccii, originally described from the European hake Merluccius merluccius in the northeast Atlantic, addressing discrepancies in clamp morphology across populations. The original description from Belgium noted near-equal anterior clamp sizes, contrasting with populations from Plymouth (Atlantic) and the Mediterranean, which show marked size differences, questioning their conspecificity. We describe A. radkeaminorum n. sp. from M. merluccius in the western Mediterranean (off Algeria), distinguished from A. merluccii (Belgium) by differing anterior clamp size, genital atrium spine number, and overall anterior clamp dimensions. Populations from Plymouth, previously attributed to A. merluccii, are herein assigned to A. aff. merluccii based on differences in morphometrical traits pending further investigations. Additionally, A. radkeaminorum n. sp. differs from A. americanus in body and clamp size, atrial spine count, and hosts. Based on analysis of morphological and molecular data, we refute the synonymy of A. merluccii and A. americanus, and we reinstate the latter as a valid species. The distinction between A. merluccii and A. americanus was further supported by divergence in cox1 gene sequences analyzed from GenBank (10–11%). Finally, inconsistencies in terminal lappet hook morphology are discussed, cautioning against its use in species delineation. This work highlights the need for continued research to resolve species relationships within this genus.

Sea Anemone Kunitz Peptide HCIQ2c1 Reduces Histamine-, Lipopolysaccharide-, and Carrageenan-Induced Inflammation via the Suppression of Pro-Inflammatory Mediators

Inflammation is a physiological response of the immune system to infectious agents or tissue injury, which involves a cascade of vascular and cellular events and the activation of biochemical pathways depending on the type of harmful agent and the stimulus generated. The Kunitz peptide HCIQ2c1 of sea anemone Heteractis magnifica is a strong protease inhibitor and exhibits neuroprotective and analgesic activities. In this study, we investigated the anti-inflammatory potential of HCIQ2c1 in histamine- and lipopolysaccharide (LPS)-activated RAW 264.7 macrophages as well as in LPS-induced systemic inflammation and carrageenan-induced paw edema models in CD-1 mice. We found that 10 μM HCIQ2c1 dramatically decreases histamine-induced intracellular Ca2+ release and LPS-induced reactive oxygen species (ROS) production in RAW 264.7 macrophages. Moreover, HCIQ2c1 significantly inhibited the production of LPS-induced tumor necrosis factor α (TNF-α), inducible NO-synthase (iNOS), and 5-lipoxygenase (5-LO) but slightly influenced the IL-1β and cyclooxygenase-2 (COX-2) expression level in macrophages. Furthermore, intravenous administration by HCIQ2c1 at 0.1 mg/kg dose reduced LPS-induced TNF-α, IL-1β, COX-2, and iNOS gene expression in CD-1 mice. The subplantar administration of HCIQ2c1 at 0.1 mg/kg dose to mice significantly reduced carrageenan-induced paw edema by a factor of two, which is comparable to the effect of diclofenac at 1 mg/kg dose. Thus, peptide HCIQ2c1 has a strong anti-inflammatory potential by the attenuation of systemic and local inflammatory effects through the inhibition of intracellular Ca2+ release, the production of ROS and pro-inflammatory cytokines, and enzymes involved in arachidonic acid metabolism.

Considerable genetic diversity within Paragonimus heterotremus in Luang Prabang, northern Lao People's Democratic Republic.

Paragonimiasis, caused by infection with lung flukes of the genus Paragonimus, remains a significant public health concern in Southeast Asia. In Lao People's Democratic Republic (Lao PDR), information on the distribution and genetic diversity of Paragonimus species is limited. This study investigated Paragonimus metacercariae in freshwater (mountain) crabs and analyzed their genetic diversity and phylogenetic relationships. Thirty-six crabs (Indochinamon sp.) were received from Xiang Ngeun and Pak Ou in Luang Prabang Province, northern Lao PDR. Partial mitochondrial 16S rRNA sequences obtained from four crabs indicated a moderately close relationship with Indochinamon ou. A total of 81 metacercariae identified morphologically as Paragonimus heterotremus were found among 13 out of the 32 crabs dissected (40.6 %). Molecular analyses targeting the ribosomal ITS2 region and mitochondrial cytochrome c oxidase subunit 1 (cox1) gene were conducted on these metacercariae. Phylogenetic analyses revealed that P. heterotremus sequences from Lao PDR clustered with those from neighboring countries-China, Myanmar, Vietnam and Thailand-suggesting potential genetic connectivity among eastern Asian populations. Haplotype-network analysis demonstrated significant genetic diversity within P. heterotremus populations from Lao PDR, separating into two distinct haplotype groups, one of which was unique to this study. This is the first report that Indochinamon sp. crabs serve as key intermediate host for a member of the P. heterotremus complex in Luang Prabang Province and highlights the parasite's genetic diversity in this region.

First morphological and molecular characterisation of Spirometra mansoni (Cestoda, Diphyllobothriidae) in a domestic cat from Veracruz, Mexico.

Cestodes of the genus Spirometra are multi-host parasites that are the causative agents of spirometrosis in domestic and wild carnivores and sparganosis in humans, endemic diseases in tropical and subtropical regions. In domestic animals, the infection is usually asymptomatic or produces gastrointestinal signs such as vomiting and chronic diarrhoea. In humans, an incidental parasitosis develops where the plerocercoid can lodge in tissues and cause a variety of symptoms, including neuropathies, blindness, paralysis, and death. Reported here is a case of spirometrosis in a domestic cat treated in a veterinary clinic in Veracruz, Mexico. The cat presented with an approximate 50cm section of the strobila protruding from the anus. The proglottids and eggs of the cestode were morphologically identified. DNA was obtained from the proglottids for the amplification and sequencing of a fragment of the cytochrome oxidase subunit 1 (cox1) gene. Genetic analysis demonstrated 100% similarity to Spirometra mansoni. The cat was treated orally with ivermectin/praziquantel (2mg/50mg), and the dose was repeated 24h later. The cat was observed daily for seven days, and no adverse effects occurred. On days 8 and 68 post-treatment, coprological examination revealed no evidence of the parasite. This is the first report of spirometrosis in cats from Mexico.

Genetic identification of zoonotic parasite Anisakis pegreffii (Nematoda: Anisakidae) parasitizing the shortfin squid Illex argentinus under commercial exploitation in the Southwestern Atlantic Ocean.

Despite the shortfin squid, Illex argentinus, is one of the most important commercial species for the Argentine fisheries, being the third frozen product exported to Europe, the occurrence and distribution of zoonotic anisakid nematodes is scarcely reported. A total of 712 I. argentinus distributed in 17 samples, corresponding to its three main commercial stocks, caught along its distribution range in Argentine waters were examined for anisakid parasites. In total, 360 nematodes were detected in the viscera, however no infestations in the mantle were observed. According to their morphology, all the larvae (L3) were assigned to the genus Anisakis. Genetic identification was performed by sequence analysis of the mitochondrial (mtDNA cox2) gene loci resulting in the record of only Anisakis pegreffii. Distance-based multiple linear regressions (DistLM) evidenced that dorsal mantle length (ML) and date of capture (as surrogate of cohort) were the most important predictors of parasite abundance across infrapopulations in I. argentinus. At component population, DistLM analysis showed that ML and latitude (indirectly representing a gradient in water temperature) were the most important variables determining the prevalence of parasites, however, its mean abundance was only influenced by ML. Parasite burdens were temporally inestable, due to variability in recruitment to host populations, being associated with changing hydrographic conditions and the opportunistic feeding behaviour and annual life cycle of the hosts. The genetic identification of A. pegreffii is relevant for both human health and the fishery industry, given its importance as an etiological agent of human anisakiosis. Due to the restriction of larvae to internal organs, the risk of anisakiosis by the consumption of edible parts of I. argentinus is low.

DNA-elucidated life cycle of a highly pathogenic avian nematode: Streptocara incognita (Spirurida: Acuariidae) and its morphological development from infective third-stage larva to adult.

Streptocara incognita Gibson, 1968 is an acuariid nematode associated with lethal cases of streptocarosis of diverse aquatic birds in North America and Europe. This study reports S. incognita as an agent causing severe and fatal necrosis of the oesophagus and proventriculus of anatids, i.e. Somateria mollissima (L.), Marmaronetta angustirostris (Ménétriés), Tadorna tadorna (L.) and Spatula querquedula (L.), kept in open pens in the Zoological Park, Clères, France. Comparative analysis of 12S rRNA gene sequences revealed that third-stage infective nematode larvae found in the amphipod Gammarus pulex pulex (L.) in the river passing through the pens belong to S. incognita thus elucidating the life cycle of this species. A partial sequence of the cox1 gene was also generated. To complement the brief original description of S. incognita, a detailed morphological description of the adult stages is provided based on light and scanning electron microscopy. Additionally, morphological data on the developing third- and fourth-stage larvae found in the definitive host and third-stage infective nematode larvae found in G. pulex pulex are also provided. This is the first record of an intermediate host of S. incognita. Somateria mollissima, M. angustirostris and S. querquedula are new host records.