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The article discusses the efficacy of chlorine dioxide gas in destroying Syphacia muris eggs, which are commonly found in laboratory rodents. Chlorine dioxide gas is a powerful disinfectant that has antimicrobial activity against various microorganisms. The study found that chlorine dioxide gas at a concentration of 1mg per 4 hours or 4mg per 1 hour resulted in 100% kill of the eggs. This could be a useful tool in eradicating pinworms in animal facilities, as current disinfectants have limitations. The use of chlorine dioxide is considered safe and environmentally friendly. [Extracted from the article]

Abstract Polygonum cognatum Meissn. (Polygonaceae) is a wild edible plant known locally as "solucanotu, madimak" in Turkey and it has been used for various purposes, such as diuretic and antidiabetic, as well to treat oxyuris and worms internally in humans. The present study was carried out to investigate the anthelmintic activity of various extracts were obtained from the aerial parts of P. cognatum in order to justify its traditional usage in Turkish folk medicine. n -Hexane, ethyl acetate and methanol extracts were prepared from the aerial parts of the plant, successively. The anthelmintic potentials of these extracts were evaluated on mice naturally infected with Syphacia obvelata and Aspiculuris tetraptera. Cellophane perianal tape test and fecal flotation test were used for the activity screening. The results were compared with control and reference groups. In addition to all these experiments, the total amount of phenolic compounds and tannin contents thought to be responsible for the activity were evaluated for all extracts. According to the results, it has been found that the methanolic extract reduced the number of S. obvelata (66.8%) and A. tetraptera (73.4%) eggs. Moreover, the methanolic extract include higher amount of total phenolic compound (48.75 ± 0.82 mg of GA/g of extract) and tannin (30.04 ± 0.22 mg TA/g of extract) than n -Hexane (17.21 ± 0.75 mg of GA/g of extract; 6.82 ± 0.41 mg TA/g of extract) and ethyl acetate (25.06 ± 0.94 mg of GA/g of extract; 10.29 ± 0.34 mg TA/g of extract); therefore the anthelmintic activity could be related to these constituents. The present study explored the anthelmintic potential of P. cognatum. Further studies should be conducted into the mechanism of these compounds' against helminths. This study can be an important step in the discovery of new anthelmintic agents. Graphical abstract Image 1 Highlights • The present study was aimed to investigate anthelmintic activity of P. cognatum. • The methanolic extract showed significant anthelminthic activity against pinworms. • The methanolic extract includes higher amount of total phenolic compound and tannin. [ABSTRACT FROM AUTHOR]

Parasite hybrid zones resulting from host secondary contact have never been described in nature although parasite hybridization is well known and secondary contact should affect them similarly to free‐living organisms. When host populations are isolated, diverge and recontact, intimate parasites (host specific, direct life cycle) carried during isolation will also meet and so may form parasite hybrid zones. If so, we hypothesize these should be narrower than the host's hybrid zone as shorter parasite generation time allows potentially higher divergence. We investigate multilocus genetics of two parasites across the European house mouse hybrid zone. We find each host taxon harbours its own parasite taxa. These also hybridize: Parasite hybrid zones are significantly narrower than the host's. Here, we show a host hybrid zone is a suture zone for a subset of its parasite community and highlight the potential of such systems as windows on the evolutionary processes of host–parasite interactions and recombinant pathogen emergence. [ABSTRACT FROM AUTHOR]

In the present study we tested the dose andh time dependence of the antinematodal effects of carvacrol and tyhmol on Caenorabditis elegans, and the efficacy of carvacrol, thymol, p-cymene and cinnamaldehyde, which were administrated in the drinking water of rats naturally infected with the pinworm Syphacia muris. The control treatment of the infected rats was carried out with piperazine. Thymol caused a dose and timedependent mortality in adult C. elegans. The value of the Median Lethal Concentration (LC50) of thymol was 117.9nM after 24h and 62.89 nM after 48h of exposure. Carvacrol exhibited a higher antinematodal efficiency than thymol. The LC50 of carvacrol, after 24 hours of exposure, was 53.03 nM, while after 48 hours it was 33.83 nM. On the other hand, piperazine showed an extremely high efficacy against S. muris infection in rats. Piperazine, at a dose of 625 mg/kg bw, administered in drinking water continuously for 10 days, eliminates the infection completely. However, none of the investigated active ingredients of essential oils were effective against S. muris. The reason for the lack of efficiency may be due to their pharmacokinetic properties. A relatively low amount of, orally administered, active ingredients of essential oils reaches the distal segments of the gastrointestinal tract, where S. muris inhabits the gut (colon and cecum). The obtained results, on C. elegans, indicate a clear dose and time-dependent antinematodal effect of thymol and carvacrol. However, for clinical application, it is necessary to examine the efficacy of microencapsulated formulations with a controlled release of active ingredients of essential oils in certain parts of the gastrointestinal tract. [ABSTRACT FROM AUTHOR]

Background: Rattus norvegicus (brown rat) and Rattus rattus (black rat) are known carriers of bacteria, viruses, and parasites of zoonotic and veterinary importance. Moreover, rats may play a role in the transmission of muscle larvae of the zoonotic nematode Trichinella spiralis to farm animals. We aimed to study the intestinal and intramuscular helminths in wild rats from three different environments to assess the relevance of rats as carrier of zoonotic parasites for public health. Materials and methods: Wild brown rats (117 individuals) and black rats (44 individuals) were captured at farms, in suburban and in rural environments in the Netherlands. Intestinal helminths were isolated and identified morphologically. Artificial digestion was used to isolate muscle larvae. Results and discussion: Morphological analysis of rat intestinal contents yielded six nematode species (Syphacia muris, Heterakis spumosa, Aonchotheca murissylvatici, Trichuris muris, Nippostrongylus brasiliensis, and Strongyloides sp.), three cestode species (Hymenolepis diminuta, H. nana and Hymenolepis (=Rodentolepis) fraterna), and four trematode species (Plagiorchis muris, Plagiorchis proximus, Echinostoma chloropodis, and Notocotylus imbricatus).Black rats at farms displayed the lowest intestinal helminth species variation (six species) and carried overall on average 0.93 species simultaneously. In comparison, brown rats at farms carried seven helminth species and 1.91 species simultaneously. Brown rats from suburban environments displayed the highest species variation (11 species) at 1.82 simultaneous helminth species. Absence of trematodes from rats at farms may suggest limited exchange of rats between farms and surrounding wet rural environments. We report four species of veterinary (Syphacia muris) or zoonotic relevance (Hymenolepis diminuta, Hymenolepis nana and Plagiorchis muris). We did not find Trichinella muscle larvae, consistent with long-term prevalence in Dutch wild rats.

Helminth specimens representing 3 cestode species, an acanthocephalan, and 15 nematode species were collected from the digestive tracts of 30 individuals of Rattus steini (Muridae) from Papua New Guinea. Of the nematode morphotypes, 7 could be identified to species level and there was insufficient material to fully identify the remainder. All were new host records. A bootstrap estimator of species richness indicated that 83.6% of the expected species in the gastrointestinal helminth community of R. steini were recovered. A comparison of the gastrointestinal communities of Rattus leucopus, Rattus giluwensis, Rattus novaeguineae, and Rattus niobe with R. steini found that the dominant elements in each case were heterakids, oxyurids, and spirurids, with heligmonellids at low prevalences and intensities. [ABSTRACT FROM AUTHOR]

Concurrent studies of helminth parasites of introduced and native rodent species are few and miss the opportunity to identify potential co-invasive parasite species. This study employed molecular tools to infer the phylogeny and elucidate the origin of potentially co-invasive parasites of commensal, murid rodents by assessing introduced Rattus norvegicus, Rattus rattus, Rattus tanezumi, and native Mastomys coucha in Gauteng Province, South Africa. Genotypes of Nippostrongylus brasiliensis recovered from R. norvegicus are nearly identical to those recovered from elsewhere in the world. The pinworms, Aspiculurus tetraptera, recovered from introduced R. tanezumi and R. rattus, Syphacia muris recovered from R. tanezumi, and Syphacia obvelata recovered from indigenous M. coucha have affiliations to those recovered of laboratory rodents from the USA and China. Syphacia obvelata was previously only known as a commensal endoparasite of laboratory rodents, and the S. muris genotype recovered from R. tanezumi in this study shows an affiliation to a genotype recovered from the same host species in Indonesia which is part of the native range. The study emphasizes the need for surveillance of potential co-invasive species and contributes in documenting genetic diversity of endoparasites of well-known hosts. [ABSTRACT FROM AUTHOR]

The ability of nematodes to manipulate the immune system of their host towards a Th2 and T regulatory responses has been proposed to suppress the inflammatory response. Clinical trials have proposed a useful effect of helminth infections on improvement of inflammatory disorders. In this study, we investigated the immunomodulatory effect of Syphacia obvelata infection to induce intestinal tolerance in C57BL/6 mice. Mice were infected through the cagemates with self-infected BALB/c mice. Four weeks post-infection, expression levels of IFN-γ, TNF-α, IL-17, and IL-10 were assessed in the supernatant of mesenteric lymph node (MLN) culture. Foxp3+Treg were measured in MLN cells by flow cytometry. In the S. obvelata-infected group, the percentage of Tregs (5.2±0.4) was significantly higher than the control (3.6±0.5) (P<0.05). The levels of IL-10 (55.3±2.2 vs 35.2±3.2), IL-17 (52.9±3.8 vs 41±1.8), IFN-γ (44.8±4.8 vs 22.3±2.3) and TNF-α (71.1±5.8 vs 60.1±3.3) were significantly increased in infected mice compared to the control group (P<0.05). The above results showed the potential effects of S. obvelata to induce intestinal tolerance. Therefore, it seems that S. obvelata may increase the immunological suppressive function in the intestinal tract. [ABSTRACT FROM AUTHOR]

The pinworms of the genus Syphacia are of special interest because they have coevolutionary relationships with their murine rodent hosts. From Southeast Asia to Australia, 21 species in four subgenera have been recorded, two species of these are endemic to Sulawesi. Their biogeographical distribution and dispersal processes are discussed herein. The species composition of Syphacia seems to be mosaic among the islands, especially in Wallacea. Based on the morphological characteristics of the cephalic ends, the species of the subgenus Syphacia are divided into three lineages with square (S), round (R) and laterallyelongated (LE) cephalic shapes. The LE type is assumed to be primitive and the S and R types are derived from the LE type as shown by a molecular phylogeny based on 28S rDNA previously. This assumption was supported by the fact that the old endemics murines in the regions studied mostly harboured Syphacia with LE type A hypothesis on the formation of the host-parasite relationships between murines and subgenus Syphacia in the areas is presented. A key to Syphacia species recorded is also provided. [ABSTRACT FROM AUTHOR]

We present the results of paleoparasitological analyses in coprolites of Kerodon rupestris, rodent endemic to rocky areas of Brazil's semiarid region. The coprolites were collected from excavations at the archaeological site of Toca dos Coqueiros, in the National Park of Serra da Capivara, southeastern of state of Piauí. Syphacia sp. (Nematoda: Oxyuridae) eggs were identified in coprolites dated at 5,300 ± 50 years before present. This is the first record of the genus Syphacia in rodent coprolites in the Americas.

Pinworm nematodes of the genus Syphacia (Nemata : Oxyurida : Oxyuridae) have a global distribution, and infect the caecum of rodents. Within the Australian Bioregion, 17 species of Syphacia infect a range of rodent hosts. Pinworms are traditionally thought to have coevolutionary relationships with their hosts, but the evolution and dispersal of Australian rodents and their helminths remains unclear. This combination of factors allowed us to investigate the likely relationships of Australian Syphacia species based on phylogenetic analysis, overlaid with the ecology and relationships of host species. We conducted a phylogenetic analysis using morphological characters of the species of Syphacia from the Australian Bioregion in order to examine the relationships between species, and to investigate how host evolution and phylogeny could inform (or be informed) by parasite phylogeny. Application of the taxon pulse theory of parasite speciation by matching host species to parasites shed some light on the timing of speciation of rodent hosts. We found that species of Syphacia had reasonably close host-parasite relationships, with additional evidence for ecological fitting or host switching occurring. Evidence provided here suggests strongly that most elements of the Stockholm Paradigm are at play in structuring the relationships we observe in this pinworm-mammal system. [ABSTRACT FROM AUTHOR]

One of the problems frequently faced in laboratory facilities is the possibility of the natural parasitic infection of lab animals, which can interfere with biomedical research results. The present study aimed to evaluate cross-reactivity among serum samples from Wistar rats ( Rattus norvegicus ) naturally infected with Syphacia muris and experimentally infected with Strongyloides venezuelensis . Forty rats were divided into four groups of ten animals each. Parasite load was evaluated by quantifying the adult worms from both helminthes species recovered from the intestines and the S. venezuelensis eggs eliminated in feces. Serological cross-reactivity by parasite-specific IgG detection was tested via enzyme linked immunosorbent assay (ELISA), immunofluorescence antibody test (IFAT) and immunoblotting. The results demonstrated that the quantity of S. venezuelensis eliminated eggs and parthenogenetic females decreased significantly in cases of co-infection with S. muris . ELISA revealed 100% cross-reactivity of serum samples from both species against the opposing antigen. IgG cross-reactivity was confirmed by IFAT using tissue sections of S. venezuelensis larvae and adult S. muris . Immunoblotting showed that IgG antibodies from the sera of animals infected with S. muris recognized eight antigenic bands from S. venezuelensis saline extract and that IgG antibodies from the sera of animals infected with S. venezuelensis recognized seven bands from S. muris saline extract. These results demonstrate the serological cross-reactivity between S. muris and S. venezuelensis in infected rats. [ABSTRACT FROM AUTHOR]

Syphacia obvelata is a pinworm nematode parasite infecting man and laboratory animals in high abundance. This parasitological study was carried out during the period of March 2014-February 2015 to investigate the helminth parasites infecting the laboratory mice Mus musculus in the Animal House at Cairo University, Egypt. The prevalence of S. obvelata in M. musculus was 75.0 %. The extent of infection with S. obvelata is analyzed according to the sex of the host mice. It was shown that the prevalence of male infection was greater than female worms. Morphological characterization revealed that the present Oxyurid species possesses a rounded cephalic end with less developed lips, esophagus divided into cylindrical corpus, and globular bulb supported internally with valvular apparatus; three mamelons are located at the ventral surface with a single chitinized spicule and a gubernaculum provided with an accessory hook in males, and ovijector apparatus opens ventrally by the vulva surrounded by protruded lips in female worms. Body of the male was 0.623-1.130 (0.830 ± 0.11) mm long and 0.092-0.130 (0.110 ± 0.01) mm wide; the esophagus was 0.164-0.280 (0.210 ± 0.01) mm long; the nerve ring and excretory pore are located at 0.035-0.132 (0.073 ± 0.01) and 0.087-0.191 (0.145 ± 0.01) mm from the anterior end, respectively, while the female measured 2.930-4.650 (3.540 ± 0.1) mm long and 0.120-0.232 (0.156 ± 0.001) mm wide; the esophagus was 0.213-0.410 (0.342 ± 0.01) mm long; the nerve ring, excretory pore, and vulval opening are located at 0.026-0.157 (0.121 ± 0.01), 0.134-0.243 (0.195 ± 0.01), and 0.323-0.632 (0.546 ± 0.11) mm from the anterior end, respectively; eggs measured 0.120-0.139 (0.129 ± 0.001) mm long and 0.030-0.052 (0.045 ± 0.001) mm wide. It compared morphometrically with other Syphacia species described previously and showed little differences in measurements. Molecular characterization based on small subunit ribosomal DNA (rDNA) was done to confirm the obtained morphological and morphometric results. A preliminary genetic comparison between SSU rDNA of the present parasite and other species of Oxyuridae places it as a putative sister taxon to other S. obvelata. [ABSTRACT FROM AUTHOR]

This study was carried out to investigate how pinworm infection in rats affects nutrient digestibility in the hosts. Twenty-four male outbred Wistar rats were randomly divided into two groups of 12 rats each. The rats from the first group (GI) were kept in cages with bedding containing pinworm eggs, and the second (control) group (GII) were kept in a separate room in clean, uncontaminated filter-top cages. The animals were put into individual metabolic cages later. Metabolic trials lasted five days and records of animal weight, food ingestion, and faecal weight were taken daily. Based on laboratory analysis of the feed and faecal nutrient content, digestibility values were determined. On day 15 of the experiment, the animals were euthanized. Although Syphacia muris were found in all rats from the GI group, animals exhibited no clinical signs. In our experiment, S. muris infection reduced the overall digestibility of all measured nutrients (P < 0.01). The most significant differences in digestibility were observed in the case of crude fibre and mineral matter (P < 0.01). [ABSTRACT FROM AUTHOR]

Background: Rattus norvegicus (brown rat) and Rattus rattus (black rat) are known carriers of bacteria, viruses, and parasites of zoonotic and veterinary importance. Moreover, rats may play a role in the transmission of muscle larvae of the zoonotic nematode Trichinella spiralis to farm animals. We aimed to study the intestinal and intramuscular helminths in wild rats from three different environments to assess the relevance of rats as carrier of zoonotic parasites for public health. Materials and methods: Wild brown rats (117 individuals) and black rats (44 individuals) were captured at farms, in suburban and in rural environments in the Netherlands. Intestinal helminths were isolated and identified morphologically. Artificial digestion was used to isolate muscle larvae. Results and discussion: Morphological analysis of rat intestinal contents yielded six nematode species (Syphacia muris, Heterakis spumosa, Aonchotheca murissylvatici, Trichuris muris, Nippostrongylus brasiliensis, and Strongyloides sp.), three cestode species (Hymenolepis diminuta, H. nana and Hymenolepis (=Rodentolepis) fraterna), and four trematode species (Plagiorchis muris, Plagiorchis proximus, Echinostoma chloropodis, and Notocotylus imbricatus). Black rats at farms displayed the lowest intestinal helminth species variation (six species) and carried overall on average 0.93 species simultaneously. In comparison, brown rats at farms carried seven helminth species and 1.91 species simultaneously. Brown rats from suburban environments displayed the highest species variation (11 species) at 1.82 simultaneous helminth species. Absence of trematodes from rats at farms may suggest limited exchange of rats between farms and surrounding wet rural environments. We report four species of veterinary (Syphacia muris) or zoonotic relevance (Hymenolepis diminuta, Hymenolepis nana and Plagiorchis muris). We did not find Trichinella muscle larvae, consistent with long-term prevalence in Dutch wild rats. [ABSTRACT FROM AUTHOR]

A new oxyurid nematode Syphacia (Syphacia) longaecauda n. sp. is described from the caecum and colon of the hydromyine rodents Melomys monktoni (type host) and M. rubex from Papua New Guinea and Irian Jaya, Indonesia. Syphacia longaecauda has an oval, laterally extended, relatively large cephalic plateau and can be distinguished from other species of Syphacia with similar characters by, amongst other features, tail length. The significance of the distribution of S. longaecauda, apparently restricted to New Guinea, is discussed.

The present report describes Syphacia (Syphacia) maxomyos sp. n. (Nematoda: Oxyuridae) from two species of spiny rats, Maxomys musschenbroekii from Sulawesi and M. whiteheadi from Sumatra. It is characterized by a cephalic plate extending laterally with dorsoventral constriction and stumpy eggs with an operculum rim reaching pole. It is readily distinguishable by the former feature from all of hitherto known representatives of this genus in Indonesia, but it resembles parasites in Murini and Hydromyni rodents in continental Asia and Sahul. This is the first Syphacia species distributed in both the Sunda Shelf and Sulawesi with the exception of Syphacia muris, a cosmopolitan pinworm found in rodents of the of genus Rattus. It is surmised that S. maxomyos is specific to Maxomys and that it was introduced to Sulawesi by dispersal of some Maxomys from the Sunda Shelf. [ABSTRACT FROM AUTHOR]

The results of this study show that the oral administration of ivermectin (48 mg/L) repeatedly for 72 h used in accordance with the present protocol is a safe and highly effective treatment for Giardia spp. and Hymenolepis nana in laboratory rat colonies. The drug can be easily and safely administered using drinking water. This simple regimen should control pinworm infection (Syphacia muris), a problem that can be endemic in laboratory colonies. Experiments using healthy animals are likely to generate more consistent results, thereby requiring a reduced number of animals per group. [ABSTRACT FROM AUTHOR]

Syphacia obvelata is a rodent nematode with high prevalence in laboratory mice. In the present study, we examined the genetic variability of S. obvelata from naturally infected laboratory mice in four different provinces, China. Five mitochondrial (mt) DNA regions, namely cytochrome c oxidase subunit 1 (p cox1), cytochrome b (p cytb), large subunit ribosomal RNA (p rrnL) and NADH dehydrogenase subunits 1 and 5 (p nad1 and p nad5), were amplified separately from individual nematodes by PCR, and then sequenced directly. The size of the sequences of p cox1, p cytb, p rrnL, p nad1 and p nad5 was 628 bp, 555 bp, 548 bp, 548 bp and 561 bp, respectively. While the intra-specific sequence variations within S. obvelata were 0-1.0% for p cox1, 0-1.6% for p cytb, 0-2.8% for p rrnL, 0-2.0% for p nad1 and 0-1.8% for p nad5, the inter-specific sequence differences among members of the Oxyuridae were significantly higher, being 14.0-17.5% for p cox1, 27.5-32.9% for p cytb, 35.8-37.2% for p rrnL, 22.2-26.8% for p nad1 and 22.3-25.2% for p nad5, respectively. Phylogenetic analyses based on combined sequences of four mt protein-coding genes, using Bayesian inference (BI), maximum likelihood (ML) and maximum parsimony (MP) methods, indicated that all of the S. obvelata samples grouped together with high statistical support, but samples from the same geographical origin did not always cluster together. These findings demonstrated the existence of low-level intra-specific variation in five mtDNA sequences among S. obvelata isolates from laboratory mice, but no obvious geographical distinction among S. obvelata isolates from laboratory mice in different geographic regions in China. These results provide basic information for further studies of systematics and population genetics of S. obvelata. [ABSTRACT FROM AUTHOR]

Diabetes mellitus is one of the most common endocrine disorders and its continuous global increase is due to factors as population growth, urbanization, aging, and increasing prevalence of obesity and physical inactivity. The effect of pinworm infection on the development of hyperglycemia was examined in WBN/K-Lepf (fa/fa) rats, a new model of the obese type 2 diabetes mellitus (T2DM) with pancreatitis. The rats were orally administered Syphacia muris eggs (infected group) and distilled water (control group). Hyperglycemia onset in the infected group was significantly delayed compared to the control group. Neither body weight nor intake of food and water were affected by S. muris infection. This study demonstrated that S. muris infection delayed the onset of T2DM in fa/fa rats and suggested that elucidation of the underlying mechanism and relevant pathways in the helminth-mediated protection may lead to the development of a new strategy to prevent diabetes mellitus. [ABSTRACT FROM AUTHOR]

A total of 1,708 small mammals (1,617 rodents and 91 soricomorphs), including Apodemus agrarius (n = 1,400), Microtus fortis (167), Crocidura lasiura (91), Mus musculus (32), Myodes (= Eothenomys) regulus (9), Micromys minutus (6), and Tscherskia (= Cricetulus) triton (3), were live-trapped at US/Republic of Korea (ROK) military training sites near the demilitarized zone (DMZ) of Paju, Pocheon, and Yeoncheon, Gyeonggi Province from December 2004 to December 2009. Small mammals were examined for their intestinal nematodes by necropsy. A total of 1,617 rodents (100%) and 91 (100%) soricomorphs were infected with at least 1 nematode species, including Nippostrongylus brasiliensis, Heligmosomoides polygyrus, Syphacia obvelata, Heterakis spumosa, Protospirura muris, Capillaria spp., Trichuris muris, Rictularia affinis, and an unidentified species. N. brasiliensis was the most common species infecting small mammals (1,060; 62.1%) followed by H. polygyrus (617; 36.1%), S. obvelata (370; 21.7%), H. spumosa (314; 18.4%), P. muris (123; 7.2%), and Capillaria spp. (59; 3.5%). Low infection rates (0.1-0.8%) were observed for T. muris, R. affinis, and an unidentified species. The number of recovered worms was highest for N. brasiliensis (21,623 worms; mean 20.4 worms/infected specimen) followed by S. obvelata (9,235; 25.0 worms), H. polygyrus (4,122; 6.7 worms), and H. spumosa (1,160; 3.7 worms). A. agrarius demonstrated the highest prevalence for N. brasiliensis (70.9%), followed by M. minutus (50.0%), T. triton (33.3%), M. fortis (28.1%), M. musculus (15.6%), C. lasiura (13.2%), and M. regulus (0%). This is the first report of nematode infections in small mammals captured near the DMZ in ROK. [ABSTRACT FROM AUTHOR]

Two new species of Syphacia (Nematoda: Oxyuridae) are described from endemic murids of Sulawesi, Indonesia: Syphacia(Syphacia)taeromyos sp. n. and S.(S.)paruromyos sp. n. parasitic in the caecum of Taeromys celebensis and Paruromys dominator, respectively. They are readily distinguished from all of the congeners recorded from Indonesia–Australian regions by having a round cephalic plate, vesicular lateral alae in the male, posteriorly positioned excretory pore in the male, and/or lacking cervical alae. Syphacia (S.) paruromyos differs from S. (S.) taeromyos by having a whip-like tail appendage in the male, longer relative distance between excretory pore and vulva, and larger eggs. The round cephalic plate in both sexes and developed vesicular lateral alae in the male are morphological traits common in endemic Syphacia species hitherto known from Sulawesi murids, suggesting that they have derived from a common ancestor and evolved with their hosts in the isolated insular environment. [ABSTRACT FROM AUTHOR]

Abstract: Syphacia muris (Nematoda: Oxyuridae) is a ubiquitous nematode that commonly infects rats in the laboratory which can interfere in the development of biological assays. The somatic extract of S. muris adults collected from infected rats was investigated using a proteomic approach. A shot-gun liquid chromatography/tandem mass spectrometry procedure was used. We used the MASCOT search engine (Matrix-Science) and ProteinPilot software v2.0 (Applied Biosystems) for the database search. A total of 359 proteins were accurately identified from the worms. The largest protein families consisted of metabolic enzymes and those involved in the nucleic metabolism and cell cycle. Proteins of transmembrane receptors and those involved in protein metabolism, chaperones, structural and motor, signalling and calcium-binding proteins also were identified in the proteome of S. muris. Proteome array of S. muris may contribute to further elucidation of biological system of S. muris as well as host–parasite relationships. [Copyright &y& Elsevier]

Five species of nematode were collected from the digestive tracts of 10 Coccymys ruemmleri from Papua New Guinea. Montistrongylus giluwensis sp. nov. can be distinguished from its congener by its size, in having more ridges in the synlophe, longer spicules and the form of the cuticle on the female posterior end. Syphacia ( S.) coccymyos can be distinguished from all other species in the subgenus by having a laterally extended dorso-ventrally constricted oval cephalic plate and both cervical and lateral alae, together with the combination spicule length and egg size. The helminth assemblage had similar species richness to that of Chiruromys vates with Odilia mackerrasae the only species in common. [ABSTRACT FROM AUTHOR]

A new oxyurid nematode Syphacia hodarae n. sp. is described from the cecum and rectum of the cricetid rodent Calomys laucha Fischer, 1814 (Sigmodontinae, Phyllotini), captured in an agroecosystem of central Argentina. The new species is distinguished from other members of the genus mainly by the shape of the cephalic plate, presence of cervical alae in females, absence of lateral alae, and absence of deirids. Some characters are shared with Syphacia carlitosi, a parasite of Akodon azarae from the wetlands in Argentina. However, S. hodarae can be differentiated from this species by the absence of ornamentation on the accessory hook of the gubernaculum, length of spicule and gubernaculum, size of the eggs, and distance to the vulva from the anterior end. This is the first record of a Syphacia species from the tribe Phyllotini in Argentina, and the first time a Syphacia species is reported from C. laucha. [ABSTRACT FROM AUTHOR]

The effects of ivermectin were studied in laboratory rats naturally infected with the pinworm Syphacia muris. Ivermectin was administered over four 5-days periods in drinking water; the ivermectin dose was 2.5 mg/kg of body weight per day. All the rats were weighed every five days and their ova production was monitored by a cellophane - tape test. Every fifth day six males and six females from the experimental group were euthanized and examined for adult pinworms and larvae. The rats' health condition, behaviour and consumption of food and water were monitored every day. The aim of this study was to investigate the effectiveness of orally administered ivermectin as a treatment against adult pinworms and their larvae in laboratory rat colonies. [ABSTRACT FROM AUTHOR]

Abstract: In this first report about pinworms peptidases we primarily characterize peptidases released during in vitro maintenance of two common pinworms of laboratory animals –Syphacia muris and Passalurus ambiguus. The peptidase activity obtained using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS–PAGE) showed the presence of peptidases from S. muris with a wide range of molecular size (25–110kDa), which degrades gelatin and mucin at alkaline pH levels. P. ambiguus released serine and aspartyl peptidases degrading gelatin at all tested pH (3, 5, 7, and 9) and at acidic pH Passalurus released aspartyl and cysteine peptidases which are active against mucin. [ABSTRACT FROM AUTHOR]

As a consequence of environmental change, it is expected that shifts in temperature and precipitation patterns will influence parasite communities and their hosts with unpredictable impact. Parasites play a vital role in ecosystems but there is only limited quantitative data which describe the effects of environmental parameters under natural conditions. We investigated the influence of rainfall, relative humidity and temperature on the prevalence, abundance and infection intensity of nematodes in southern Africa by studying the gastro-intestinal helminth community of the striped mouse Rhabdomys pumilio. Along a precipitation gradient from the Cape of South Africa to northern Namibia we trapped 470 mice over a geographical distance of about 1400 km. Faecal egg counts of 439 sampled individuals and dissections of 161 gastro-intestinal tracts revealed 15 different helminth species. The most abundant nematode species harboured in 62.6% of all infected mice were the oxyurid Syphacia obvelata followed jointly by two species ( Heligmonina spira and Neoheligmonella capensis) of the subfamily Nippostrongylinae (43.7%). We found a significant positive correlation between mean annual precipitation (rainfall and relative humidity) and nematode infestation rates of animals and a negative correlation with temperature. In addition, we found associations between precipitation and different qualitative measurements of parasite burden (mean nematode species richness, mean number of nematode worms and infection intensity per individual host). The similarity in nematode species composition decreased with distance between all study sites. Our study indicates for the first time an association between climatic variables and parasite prevalence and abundance along a continuous natural climatic gradient in a small mammal. These results might be incorporated in the development of models which can predict possible threats for the balance of ecosystems and shifts in infestation patterns due to global changes. [ABSTRACT FROM AUTHOR]

Syphacia venteli Travassos, Mem Inst Oswaldo Cruz 32:607–613, is redescribed on the basis of specimens recovered from the type host, Nectomys squamipes (Brants 1827), from Brazil and Argentina. Specimens determined by Quentin (Bull Mus Natl Hist Nat 2:909–925, ) as S. venteli from Melanomys caliginosus (Tomes 1860) in Colombia were re-studied and assigned to a new species. In both species, structures such as the shape of the cephalic plate, details and distribution of the submedian papillae and amphids, presence and absence of the lateral and cervical alae, and shape and structure of the accessory hook of the gubernaculum were studied with the light microscope and scanning electron microscope. The present survey is the first detailed study of the species S. venteli since the original description, and the first record of this species from Argentina. Moreover, the present study suggests that the validity of some host species of Syphacia should be questioned and that through of the study of deposited specimens, a more exact number of parasitized host species can be confirmed, contributing to a better understanding of host specificity in this genus. [ABSTRACT FROM AUTHOR]

Abstract: This study was performed to determine the effects of levamisole and levamisole+vitamin C against Syphacia muris naturally infection in rats and to detect its effect on the oxidative parameters in blood and tissues of host. For this purpose, natural infection was diagnosed using the cellophane tape method on the perianal region of rats. Infected rats (total 18) were divided into three groups. On the other hand six without helminth rats were used in this study as negative control group. Group 2 was given an orally levamisole HCl treatment with gastric gavage at a dose level of 20mg/kg body weight in distilled water, every alternate day. Group 3 was given levamisole HCl via gastric gavage at a dose level of 20mg/kg and vitamin C was given 1g/L added to the drinking water. All the treatments continued for a period of 7days. As a result; levamisole administered to rats at dose of 20mg/kg orally 98.34% was found to be effective against adult S. muris in the rats. In addition to levamisole+vitamin C is effective to alleviate the oxidative damage in rats infected with S. muris. [Copyright &y& Elsevier]

Abstract: Syphacia obvelata is a rodent nematode parasite with high prevalence in laboratory mice. In our previous work we have demonstrated that this gut-dwelling helminth induces significant hematopoietic changes, characterized by increased myelopoiesis and erythropoiesis in infected animals, and accompanied with altered reactivity of bone marrow hematopoietic progenitors to interleukin (IL)-17. In this study we extended these investigations by demonstrating that naturally acquired S. obvelata infection induces significant alterations in murine bone marrow cells manifested at the molecular level. Namely, S. obvelata infection induced sustained phosphorylation of the members of three major groups of distinctly regulated mitogen-activated protein kinases (MAPKs), the p38, the c-Jun amino-terminal kinase (JNK) and the extracellular signal-regulated kinase (ERK), as well as enhanced expression of mRNA for the inducible nitric oxide synthase (iNOS) in the bone marrow cells of infected animals. Furthermore, the infection interfered with the IL-17-mediated effects in bone marrow cells, since in normal mice IL-17 significantly enhanced phosphorylation of p38 MAPK and upregulated the expression of iNOS and the constitutive, endothelial (e)NOS mRNA, while in S. obvelata-infected animals IL-17 did not influence the MAPKs activation, but markedly down-regulated the expression of both NOS isoforms. The data obtained demonstrating that S. obvelata is able to manipulate signal transduction pathways in the hosts'' bone marrow cells, pointed to the multiple layers of immunomodulatory ability of this pinworm parasite and highlighted the importance of working under pinworm-free conditions when using experimental murine models for immunohematopoietic investigations. [Copyright &y& Elsevier]

Syphacia (Syphacia) rifaii sp. n. (Nematoda: Oxyuridae) is described from endemic Bunomys chrysocomus and Bunomys prolatus (Rodentia: Muridae) on Sulawesi Island, Indonesia. The new species is closest morphologically to Syphacia (Syphacia) sulawesiensis, parasitic in Rattus xanthurus from Sulawesi Island, by having large vesicular lateral alae in males, but is readily distinguished by having a smaller body, a round cephalic plate in both sexes, the absence of lateral alae in females, a longer relative distance between excretory pore and vulva, and smaller eggs. Syphacia (S.) rifaii is surmised to be a specific parasite of Bunomys spp. and has evolved from a common ancestor with S. (S.) sulawesiensis on Sulawesi Island. [ABSTRACT FROM AUTHOR]

The article presents a study on new species of Syphacia from Pseudomys group of rodents from Australia. It says that there are eight known species of Syphacia which occur mainly in rodents such as S. muris, S. abertoni, and S. pseudomyos. The species were found by examination of the whole-body specimens from the previously collected rodents at the Queensland Museum. Results show three new species which include S. helidonensis from P. gracilicaudatus, and S. boodjamullaensis from Zyzomys argurus.

Abstract: The 28S rDNA from nine species of the genus Syphacia collected in Japan was sequenced, and the phylogenetic relationship was inferred from multiple sequence alignment of 28S rDNA by the MAFFT program. Phylogenetic tree indicates that S. petrusewiczi, which was the only species belonging to the subgenus Seuratoxyuris, has diverged earlier than other rodent pinworms examined and was distantly separated from the others genetically. It was revealed that S. agraria and S. vandenbrueli, whose subgeneric status has not been specified, belonged to the subgenus Syphacia together with other 6 species. Syphacia montana from Clethrionomys, Eothenomys and Microtus was very closely related to S. obvelata from Mus, and that S. frederici from Apodemus and S. vandenbrueli from Micromys were comparatively closely related to the former two species. The phylogenetic relationship among the three species of Syphacia found in Japanese Apodemus was inconsistent with the biogeography of host rodents. The co-evolutionary relationship between pinworm species and their host rodents may not be so strict and host switching has probably occurred frequently during the course of evolution. [Copyright &y& Elsevier]

Abstract: This study was designed to determine the acute effects of a single-dose of orally administered doramectin, eprinomectin and selamectin on Syphacia muris infection in rats. Rats, naturally infected with S. muris, were divided into four groups: three different treatment groups (n =7) and one positive control (n =7). Cellophane tape preparations were obtained from the treated rats on day 0 pre-treatment and on days 2, 4 and 6 post-treatment. Syphacia sp. eggs were counted. Eprinomectin was found to be 100% effective in eliminating eggs on two post-treatment. However when egg counts on day 6 post-treatment were compared with pre-treatment egg counts, doramectin and selamectin were found to be 99.32 and 98.77% effective in eliminating eggs, respectively. On day 7 post-treatment, blood samples were obtained from all groups, and then the rats were necropsied. Doramectin, eprinomectin and selamectin were found to be 100% effective in eliminating adult S. muris, when compared with the positive control group. [Copyright &y& Elsevier]

Abstract  The aim of this paper is to describe Syphacia kinsellai n. sp. (Nematoda: Oxyuridae) from the cecum of Oligoryzomys nigripes (Olfers 1818) (Sigmodontinae: Oryzomyini) captured in Misiones Province, Argentina. The new species can be differentiated from other species of the genus principally by the shape of the cephalic plate; distribution of submedian papillae and amphids; development of porous badge; presence of derids in females; absence of cervical and lateral alae; shape and structure of accessory hook of gubernaculum; and distance of excretory pore and vulva from the anterior extremity. Until the present, only two species of Syphacia had been reported from Argentina in sigmodontine rodents, the first one parasitizes an Oryzomyini host and the second one an Akodontini host. This new species is the second record of Syphacia from the tribe Oryzomyini in Argentina; however, we propose that the first record, S. oryzomae, should be treated as a nomen dubium. [ABSTRACT FROM AUTHOR]

The article describes the Syphacia carlitosi n. sp. from the ceca of Akodon azarae bibianae and Akodon azarae hunteri captured in three provinces of Argentina. The species is differentiated principally by the shape of the cephalic plate, distribution of submedian papillae and amphids, absence of lateral alae, spicular and gubernaculum length, shape and structure of accessory hook of gubernaculum, and distance of mamelons, excretory pore, and vulva from the anterior extremity.