Molecular characterization of Anisakis pegreffii larvae in Pacific cod in Japan

2005 ◽  
Vol 79 (4) ◽  
pp. 303-306 ◽  
Author(s):  
N. Abe ◽  
N. Ohya ◽  
R. Yanagiguchi

AbstractIt is now recognized that the morphospecies Anisakis simplex is not a single species but a complex composed of three sibling species, A. simplex sensu stricto, A. pegreffii and A. simplex C. In Japan, A. simplex-like larvae have been isolated from a variety of fish and humans, but the larvae collected have been identified as A. simplex by only light microscopy. Therefore, the epidemiology of the A. simplex complex, composed of three sibling species, is still unclear in Japan. In the present study, 26 A. simplex-like larval isolates were obtained from two Pacific cod landed in Hokkaido, Japan, and examined genetically by PCR–RFLP and direct sequencing of the ITS region of rDNA. Among the 26 isolates, 24 were identified as A. simplex sensu stricto, the other two as A. pegreffii. The present study is the first to confirm the distribution of A. pegreffii in Japan, and to detect A. pegreffii larvae in Pacific cod.

Genes ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 452
Author(s):  
Xavier Roca-Geronès ◽  
M. Magdalena Alcover ◽  
Carla Godínez-González ◽  
Olga González-Moreno ◽  
Miquel Masachs ◽  
...  

Anisakiosis is a fish-borne disease with gastrointestinal and/or allergic symptoms caused by the consumption of raw or undercooked fish parasitized with nematode larvae of the genus Anisakis. In Europe, Anisakis pegreffii has been detected as the causative agent, although the sibling species Anisakis simplex sensu stricto (s.s.) is also known to cause the disease in other parts of the world, and discrepancies exist regarding their respective pathogenic potential. In Spain a high number of cases has been recorded, with marinated anchovies being the main source of infection, although no specific diagnosis has been documented in humans. In this study, we analyzed three cases of anisakiosis in patients from Barcelona (Spain) who had consumed undercooked hake. All patients described epigastric pain and several larval nematodes were removed endoscopically from their stomachs. Larvae were morphologically characterized as third-stage larvae of Anisakis simplex sensu lato (s.l.) and molecularly identified as A. simplex (s.s.) by means of PCR RFLP of the ITS region of the rDNA and sequencing of the elongation factor1 alpha1 (EF1 α-1) nDNA gen. This study represents the first specific identification of Anisakis larvae in clinical cases of anisakiosis reported in Spain. Specific molecular diagnosis is of crucial importance for assessing the health risk of Anisakis sibling species. Hake consumption stands out as a risk factor for anisakiosis, since this fish species can be highly parasitized.


2016 ◽  
Vol 26 (4) ◽  
pp. 345-350 ◽  
Author(s):  
M. Didehdar ◽  
T. Shokohi ◽  
B. Khansarinejad ◽  
S. Ali Asghar Sefidgar ◽  
M. Abastabar ◽  
...  
Keyword(s):  
Pcr Rflp ◽  

Zootaxa ◽  
2019 ◽  
Vol 4563 (2) ◽  
pp. 201 ◽  
Author(s):  
THOMAS WESENER

Before this study, giant pill-millipedes (order Sphaerotheriida) were unknown from Laos despite their presence in all surrounding countries. As by-catch from collections by arachnologists, 31 specimens of Sphaerotheriida from Laos became available for study. The sample included 14 species. Three species were only represented by females, which are described but cannot be named. Of the remaining 11 species, a single species belongs to the genus Zephronia Gray, 1832: Z. laotica n. sp.; and the other ten belong to the genus Sphaerobelum Verhoeff, 1924: S. bolavensis n. sp., S. phouloei n. sp., S. denticulatum n. sp., S. spinatum n. sp., S. lachneeis n. sp., S. peterjaegeri n. sp., S. nigrum n. sp., S. splendidum n. sp., S. laoticum n. sp., and S. schwendingeri n. sp. This more than doubles the known diversity of Sphaerobelum. Here, I integratively describe these species, combining morphology and DNA barcodes with a molecular analysis including all Zephroniidae species deposited on GenBank—including the only giant pill-millipede species known from Cambodia, Zephronia dawydoffi Attems, 1953. An updated determination key to the species of the genus is presented. Zephronia laotica n. sp. belongs to the monophyletic Zephronia sensu stricto group, which is confirmed by molecular barcoding. In contrast, most species of Sphaerobelum are in a weakly supported clade. Genetically, Sphaerobelum species differ greatly from one another, with most p-distances >15%. The lowest observed p-distance (9.8%) is between S. truncatum Wongthamwanich et al. 2012 from Thailand and S. peterjaegeri n. sp. 


1981 ◽  
Vol 59 (12) ◽  
pp. 2744-2751 ◽  
Author(s):  
J. McNeill

The introduced nonmaritime knotweeds have generally been regarded in North America as comprising a single species called P. aviculare L. In recent years cytological and morphological studies have suggested that at least two chromosome races are present and that certain morphological features are correlated with chromosome number. There have been, however, discrepancies in the reports of the distribution and relative abundance of the two races. Studies of the morphology and cytology of introduced knotweeds in eastern Canada confirm the existence of two groups that are recognizable at species rank, and establish that the most common knotweeds in open habitats, e. g., along roadsides and sidewalks, are tetraploid plants distinguishable from their hexaploid relatives by the relatively uniform size of their leaves, the short and narrow free portion of the perianth segments, and by one side of the fruit being very much narrower than the other two. These plants are referable to P. arenastrum Boreau. This species is compared with the heterophyllous hexaploid, usually called P. aviculare sensu stricto, or, if that is considered a nomen ambiguum, P. monspeliense Pers. A table of distinguishing features, illustrations of the two species, and maps of their distribution in eastern Canada are provided.


2020 ◽  
Vol 367 (5) ◽  
Author(s):  
Deeksha Mishra ◽  
Archana Suradkar ◽  
Aniket Saraf ◽  
Prashant Singh

ABSTRACT Soil inhabiting true branching heterocytous cyanobacterium strain SNS 3 with T-type branching was collected from the campus of Banaras Hindu University, India and characterized using the polyphasic approach. Morphological observations showed the presence of akinetes (in chain), hormogonia and monocytes. Physiological characterization of strain SNS 3 showed high content of carotenoid in comparison to chlorophyll a content along with also exhibiting a higher C/N ratio in the nitrogen deficient BG110 medium. 16S rRNA gene sequencing and subsequent phylogeny indicated strong clustering of the strain SNS 3 within the Westiellopsis clade. Folded secondary structures of the ITS region showed visible differences in the D1-D1’ and BoxB helix of the strain SNS 3. The polyphasic approach indicated the strain SNS 3 as a new member of the genus Westiellopsis with the name proposed being Westiellopsis akinetica sp. nov. on the basis of the International Code of Nomenclature for Algae, Fungi and Plants. Intense phylogenetic evaluation of the entire true-branched heterocytous clade indicated the need for more revisionary attempts for demarcating the sensu stricto clades along with highlighting the scope for further taxonomic revisions in the future.


2014 ◽  
Vol 89 (4) ◽  
pp. 512-515 ◽  
Author(s):  
A.M. Sparks ◽  
M. Betson ◽  
G. Oviedo ◽  
C. Sandoval ◽  
P.J. Cooper ◽  
...  

AbstractTo shed light on the epidemiology of ascariasis in Ecuador and Zanzibar, 177 adult worms retrieved by chemo-expulsion from either people or pigs were collected, measured and subjected to polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) analysis of the ribosomal internal transcribed spacer (ITS) region. Upon double digestion with RsaI and HaeIII, PCR-RFLP analysis revealed the presence of A. lumbricoides in people and A. suum in pigs in Ecuador. In contrast, while there are no pigs on Zanzibar, of the 56 worms obtained from people, one was genotyped as A. suum. No additional genetic variation was detected upon further PCR-RFLP analysis with several other restriction enzymes. Upon measurement, worm mass and length differed by location and by species, A. suum being lighter and longer. While there is no evidence to suggest zoonotic transmission in Ecuador, an enduring historical signature of previous zoonotic transmission remains on Zanzibar.


Author(s):  
J. I. Bennetch

In a recent study of the superplastic forming (SPF) behavior of certain Al-Li-X alloys, the relative misorientation between adjacent (sub)grains proved to be an important parameter. It is well established that the most accurate way to determine misorientation across boundaries is by Kikuchi line analysis. However, the SPF study required the characterization of a large number of (sub)grains in each sample to be statistically meaningful, a very time-consuming task even for comparatively rapid Kikuchi analytical techniques.In order to circumvent this problem, an alternate, even more rapid in-situ Kikuchi technique was devised, eliminating the need for the developing of negatives and any subsequent measurements on photographic plates. All that is required is a double tilt low backlash goniometer capable of tilting ± 45° in one axis and ± 30° in the other axis. The procedure is as follows. While viewing the microscope screen, one merely tilts the specimen until a standard recognizable reference Kikuchi pattern is centered, making sure, at the same time, that the focused electron beam remains on the (sub)grain in question.


Author(s):  
D. R. Abrahamson ◽  
P. L. St.John ◽  
E. W. Perry

Antibodies coupled to tracers for electron microscopy have been instrumental in the ultrastructural localization of antigens within cells and tissues. Among the most popular tracers are horseradish peroxidase (HRP), an enzyme that yields an osmiophilic reaction product, and colloidal gold, an electron dense suspension of particles. Some advantages of IgG-HRP conjugates are that they are readily synthesized, relatively small, and the immunolabeling obtained in a given experiment can be evaluated in the light microscope. In contrast, colloidal gold conjugates are available in different size ranges and multiple labeling as well as quantitative studies can therefore be undertaken through particle counting. On the other hand, gold conjugates are generally larger than those of HRP but usually can not be visualized with light microscopy. Concern has been raised, however, that HRP reaction product, which is exquisitely sensitive when generated properly, may in some cases distribute to sites distant from the original binding of the conjugate and therefore result in spurious antigen localization.


Author(s):  
George Guthrie ◽  
David Veblen

The nature of a geologic fluid can often be inferred from fluid-filled cavities (generally <100 μm in size) that are trapped during the growth of a mineral. A variety of techniques enables the fluids and daughter crystals (any solid precipitated from the trapped fluid) to be identified from cavities greater than a few micrometers. Many minerals, however, contain fluid inclusions smaller than a micrometer. Though inclusions this small are difficult or impossible to study by conventional techniques, they are ideally suited for study by analytical/ transmission electron microscopy (A/TEM) and electron diffraction. We have used this technique to study fluid inclusions and daughter crystals in diamond and feldspar.Inclusion-rich samples of diamond and feldspar were ion-thinned to electron transparency and examined with a Philips 420T electron microscope (120 keV) equipped with an EDAX beryllium-windowed energy dispersive spectrometer. Thin edges of the sample were perforated in areas that appeared in light microscopy to be populated densely with inclusions. In a few cases, the perforations were bound polygonal sides to which crystals (structurally and compositionally different from the host mineral) were attached (Figure 1).


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