Background: Pomacea canaliculata (Lamarck, 1819) is an invasive freshwater snail in the Philippines that damages crops but is consumed as food. It is known to harbor parasites, some of which are pathogenic to humans. Objectives: The objective of this study is to examine P. canaliculata individuals present in Metro Manila for parasite infection and identify the parasites and other organisms associated with the snail using molecular identification. Methodology: P. canaliculata were collected from rivers and marketplaces in Metro Manila. Individuals were crushed and digested in Ash's digestive fluid and observed under a microscope. Collected parasites were subjected to DNA barcoding of the COI gene for putative identification. Results: A total of 462 snails were gathered from 15 sites, eight of which were market areas that sourced the snails from outside Metro Manila. No known parasites were found. Two snails were found to contain insect larvae in the mantle (0.43% infection). The closest BLAST matches for the two insect larvae were the chironomid fly Nilodorum tainanus (91.0% identity) from a snail in Sucat, Muntinlupa, and another chironomid Parachironomus sp. (92.8% identity) found in a snail originally from Cavite and brought to Calumpang, Marikina. Conclusion This study is the first report of the presence of chironomids in Philippine P. canaliculata. This could have an impact on the allergenic status of these mollusks if consumed while containing these chironomids. The absence of infection of other medically important parasites is possibly due to the patchy distribution of the snails and few interactions with the definitive hosts of known parasites.
Chironomidae ; Diptera

OBJECTIVES: This study aims to evaluate the size-dependent toxicity of spherical silver nanoparticles (Ag NPs) to an endemic benthic organism, Glyptotendipes tokunagai. METHODS: Ag nanoparticles of three nominal sizes (50, 100, and 150 nm) capped with polyvinyl pyrrolidone (PVP-Ag NPs) were used. Their physicochemical properties, acute toxicity (48 hours), and bioaccumulation were measured using third instar larvae of G. tokunagai. RESULTS: The aggregation and dissolution of PVP-Ag NPs increased with exposure time and concentration, respectively, particularly for 50 nm PVP-Ag NPs. However, the dissolved concentration of Ag ions was not significant compared with the median lethal concentration value for AgNO3 (3.51 mg/L). The acute toxicity of PVP-Ag NPs was highest for the smallest particles (50 nm), whereas bioaccumulation was greatest for the largest particles (150 nm). However, larger PVP-Ag NPs were absorbed and excreted rapidly, resulting in shorter stays in G. tokunagai than the smaller ones. CONCLUSIONS: The size of PVP-Ag NPs significantly affects their acute toxicity to G. tokunagai. In particular, smaller PVP-Ag NPs have a higher solubility and stay longer in the body of G. tokunagai, resulting in higher toxicity than larger PVP-Ag NPs.
Chironomidae ; Ions ; Larva ; Nanoparticles* ; Polyvinyls ; Silver* ; Solubility

OBJECTIVES: This study aims to evaluate the size-dependent toxicity of spherical silver nanoparticles (Ag NPs) to an endemic benthic organism, Glyptotendipes tokunagai. METHODS: Ag nanoparticles of three nominal sizes (50, 100, and 150 nm) capped with polyvinyl pyrrolidone (PVP-Ag NPs) were used. Their physicochemical properties, acute toxicity (48 hours), and bioaccumulation were measured using third instar larvae of G. tokunagai. RESULTS: The aggregation and dissolution of PVP-Ag NPs increased with exposure time and concentration, respectively, particularly for 50 nm PVP-Ag NPs. However, the dissolved concentration of Ag ions was not significant compared with the median lethal concentration value for AgNO3 (3.51 mg/L). The acute toxicity of PVP-Ag NPs was highest for the smallest particles (50 nm), whereas bioaccumulation was greatest for the largest particles (150 nm). However, larger PVP-Ag NPs were absorbed and excreted rapidly, resulting in shorter stays in G. tokunagai than the smaller ones. CONCLUSIONS: The size of PVP-Ag NPs significantly affects their acute toxicity to G. tokunagai. In particular, smaller PVP-Ag NPs have a higher solubility and stay longer in the body of G. tokunagai, resulting in higher toxicity than larger PVP-Ag NPs.
Chironomidae ; Ions ; Larva ; Nanoparticles* ; Polyvinyls ; Silver* ; Solubility

Huge numbers of non-biting midges emerged from brackish water which were made at the harbor construction field in Jinhae City, Kyongsangnam-do, Korea in late summer in 2005, and caused a serious nuisance to villagers. The midges were collected and identified as Chironomus salinarius (Kieffer, 1921). Although this species was recorded in Korea for the first time in 1998, the morphological descriptions were so brief and simple. A full redescription is made with detailed illustrations for ecological and control workers of this nuisance midge.
Wing/anatomy & histology ; Species Specificity ; Seawater ; Male ; Korea ; Female ; Chironomidae/*anatomy & histology/*classification ; Animals ; Animal Structures/anatomy & histology

OBJECTIVES: Chironomus riparius, a non-biting midge (Chironomidae, Diptera), is extensively used as a model organism in aquatic ecotoxicological studies, and considering the potential of C. riparius larvae as a bio-monitoring species, little is known about its genome sequences. This study reports the results of an Expressed Sequence Tags (ESTs) sequencing project conducted on C. riparius larvae using 454 pyrosequencing. METHODS: To gain a better understanding of C. riparius transcriptome, we generated ESTs database of C. ripairus using pyrosequencing method. RESULTS: Sequencing runs, using normalized cDNA collections from fourth instar larvae, yielded 20,020 expressed sequence tags, which were assembled into 8,565 contigs and 11,455 singletons. Sequence analysis was performed by BlastX search against the National Center for Biotechnology Information (NCBI) nucleotide (nr) and uniprot protein database. Based on the gene ontology classifications, 24% (E-value < or =1(-5)) of the sequences had known gene functions, 24% had unknown functions and 52% of sequences did not match any known sequences in the existing database. Sequence comparison revealed 81% of the genes have homologous genes among other insects belonging to the order Diptera providing tools for comparative genome analyses. Targeted searches using these annotations identified genes associated with essential metabolic pathways, signaling pathways, detoxification of toxic metabolites and stress response genes of ecotoxicological interest. CONCLUSIONS: The results obtained from this study would eventually make ecotoxicogenomics possible in a truly environmentally relevant species, such as, C. riparius.
Biotechnology ; Chironomidae ; Databases, Protein ; Diptera ; DNA, Complementary ; Ecotoxicology ; Expressed Sequence Tags ; Genome ; Insects ; Larva ; Metabolic Networks and Pathways ; Sequence Analysis ; Transcriptome

To evaluate the significance of chironomid as a respiratory allergen, we performed skin prick tests with Chironomus plumosus (CP) and Tokunagayusurika akamusi (TA) extracts on 475 respiratory allergy patients, and their specific IgE antibodies were detected by enzyme-linked immunosorbent assay (ELISA) in 106 positive reactors to skin prick test and 30 negative controls. Ninety-seven (20.4%) showed more than 2+ of allergen to histamine ratio to CP and 98 (20.6%) to TA on skin prick test. Seventy-one (73.2%) of 97 positive reactors had increased specific IgE to CP, and 34 (34.7%) of 98 positive reactors, to TA. CP-specific IgE was detected in 14 (14.4%) non-atopic asthmatics and 6 (6.2%) non-allergic rhinitis patients. TA-specific IgE was detected in 17 (17.4%) non-atopic asthmatics and 6 (6.1%) non-allergic rhinitis patients. No association was noted between skin reactivity to Dermatophagoides farinae and the prevalence of specific IgE to CP or TA (p > 0.05). The correlation between total IgE level and specific IgE level to CP and TA was poor (r = 0.07, 0.04). ELISA inhibition test suggested specificity of IgE binding and cross-allergenicity between CP and TA. It is suggested that CP and TA can induce IgE-mediated reaction in exposed patients and should be considered as important causative allergens in respiratory allergy patients in Korea.
Allergens/*immunology ; Animals ; Chironomidae/*immunology ; Enzyme-Linked Immunosorbent Assay ; Humans ; Immunoglobulin E/*biosynthesis ; Korea ; Prevalence ; Respiratory Hypersensitivity/*immunology ; Skin/*immunology ; Skin Tests

PURPOSE: Chironomids (nonbiting midges) are widely and abundantly distributed near ponds, rivers, and artificially dammed pools used for irrigation. Chironomids contain allergens and cause airway allergy in humans. In this study, we aimed to examine the allergic potential of chironomids in inhabitants living near artificially dammed pools. METHODS: We examined immunoglobulin E (IgE) reactivity to chironomid extracts in the sera of residents living around installed dams and assessed the correlations of IgE responses between chironomids (Chironomus flaviplumus, Chironomus kiiensis, Cricotopus bicinctus) and house dust mites (Dermatophagoides farinae). In addition, we identified potential IgE binding proteins specific for adult C. bicinctus, a popular species in Korea. Specific IgE antibodies in sera collected from the participants against the extracts were tested using enzyme-linked immunosorbent assay (ELISA). RESULTS: The average IgE-positive rates were 10.4%, 8.1%, and 8.2% in C. bicinctus, C. flaviplumus, and C. kiiensis, respectively. The IgE-positive rate and IgE titer of C. bicinctus antigen were higher in residents living around installed dams than in those who lived other places (P = 0.013). Western blotting using sera having high IgE titers to C. bicinctus in ELISA showed the presence of a protein of approximately 42 kDa that was homologous to the actin protein isoform in C. bicinctus extracts as demonstrated using mass spectrometry. CONCLUSIONS: Our results showed that people living near installed dams were more sensitized to C. bicinctus and that the 42 kDa IgE-binding protein could be useful for further studies on chironomid allergic disease and clinical applications.
Actins ; Adult ; Allergens ; Antibodies ; Blotting, Western ; Chironomidae ; Enzyme-Linked Immunosorbent Assay ; Galectin 3 ; Humans ; Hypersensitivity ; Immunoglobulin E ; Immunoglobulins ; Korea ; Mass Spectrometry ; Ponds ; Pyroglyphidae ; Rivers