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61.
Rengifo-Herrera C Ortega-Mora LM Gómez-Bautista M García-Moreno FT García-Párraga D Castro-Urda J Pedraza-Díaz S 《Applied and environmental microbiology》2011,77(4):1524-1527
The presence of Cryptosporidium and Giardia in 221 fecal samples from different species of Antarctic pinnipeds was investigated by immunofluorescence microscopy and PCR. Cryptosporidium, a skunk-like genotype, was detected only in a southern elephant seal. Giardia was not detected. This is the first report of a Cryptosporidium sp. in Antarctic marine mammals. 相似文献
62.
Claudia Rengifo-Herrera Ignacio Ferre Luis Miguel Ortega-Mora Silvia Rojo-Montejo Francisco Tomás García-Moreno Daniel García-Párraga Francisco Javier García-Peña Juana Pereira-Bueno Susana Pedraza-Díaz 《Polar Biology》2014,37(5):685-695
Information on helminth parasites in Antarctic phocids is scarce and fragmented. Anisakidae nematodes and Diphyllobothriidae cestodes have been reported in Antarctic and subantarctic phocids, although the prevalence and health significance remain unclear. In the present study, the presence of helminth parasites in faeces of Leptonychotes weddellii, Hydrurga leptonyx and Mirounga leonina has been investigated. Faecal samples were collected from different locations of the Antarctic Peninsula. Macroscopical inspection and standard flotation and migration techniques were used for faecal examination. Eggs, larvae and adult parasites of nematodes and cestodes were found in 76.9 % of samples analysed. Positive samples were recorded from all locations surveyed and species investigated. The prevalence was 71.3 % for M. leonina, 95.4 % for L. weddellii and 100 % for H. leptonyx. Anisakidae (eggs and worms), Metastrongyloidea (larvae) and Diphyllobothriidae (eggs) were identified in M. leonina and L. weddellii. Metastrongyloidea (larvae) and Diphyllobothriidae (eggs) were found in H. leptonyx. Molecular characterisation of some of the adult parasites found was useful for the identification of Anisakis simplex and Pseudoterranova sp. in M. leonina, and Contracaecum sp., Contracaecum osculatum, and Pseudoterranova sp. in L. weddellii. 相似文献
63.
64.
ZSOLT PÉNZES GEORGE MELIKA ZOLTÁN BOZSÓKI PÉTER BIHARI ISTVÁN MIKÓ MAJID TAVAKOLI JULI PUJADE‐VILLAR BALÁZS FEHÉR DÁVID FÜLÖP KRISZTIÁN SZABÓ MIKLÓS BOZSÓ BOTOND SIPOS KÁLMÁN SOMOGYI GRAHAM N. STONE 《Systematic Entomology》2009,34(4):688-711
Several unanswered questions remain regarding the taxonomy and phylogeny of inquiline gallwasps (Cynipidae: Synergini), obligate inhabitants of plant galls induced primarily by other gallwasps (Cynipidae: Cynipini and Diplolepidini). Here we use morphological and molecular data to revise the inquiline genus Synophrus, members of which are notable for extensively modifying the structure of galls induced by oak gallwasp hosts on oaks in the section Cerris of Quercus subgenus Quercus in the Western Palaearctic. Previous taxonomic treatments have recognized three Western Palaearctic species of Synophrus: S. pilulae, S. politus and S. olivieri. Our results support the establishment of four additional Western Palaearctic species: Synophrus hungaricus sp.n. , S. libani sp.n. , S. syriacus sp.n. and S. hispanicus sp.n. We describe and diagnose these new taxa, analyse their phylogenetic relationships, and show that Synophrus inquilines are able to impose their own gall phenotypes on those of their hosts. We provide an updated key to Synophrus. 相似文献
65.
In the previous issue of Arthritis Research & Therapy, Ducourau and colleagues report that they retrospectively detected anti-infliximab antibodies in 21% of patients with rheumatic
diseases. Patients with anti-infliximab antibodies had lower serum drug concentrations. These findings contribute to the existing
evidence of immunogenicity of biologicals and its clinical relevance. We argue for therapeutic drug monitoring to optimize
treatment response. 相似文献
66.
Alexandre C Motta Joost LM Vissers Renée Gras Betty CAM Van Esch Antoon JM Van Oosterhout Martijn C Nawijn 《Respiratory research》2009,10(1):1-8
Background
Anxiety and depression are common and treatable risk factors for re-hospitalisation and death in patients with COPD. The degree of lung function impairment does not sufficiently explain anxiety and depression. The BODE index allows a functional classification of COPD beyond FEV1. The aim of this cross-sectional study was (1) to test whether the BODE index is superior to the GOLD classification for explaining anxious and depressive symptoms; and (2) to assess which components of the BODE index are associated with these psychological aspects of COPD.Methods
COPD was classified according to the GOLD stages based on FEV1%predicted in 122 stable patients with COPD. An additional four stage classification was constructed based on the quartiles of the BODE index. The hospital anxiety and depression scale was used to assess anxious and depressive symptoms.Results
The overall prevalence of anxious and depressive symptoms was 49% and 52%, respectively. The prevalence of anxious symptoms increased with increasing BODE stages but not with increasing GOLD stages. The prevalence of depressive symptoms increased with both increasing GOLD and BODE stages. The BODE index was superior to FEV1%predicted for explaining anxious and depressive symptoms. Anxious symptoms were explained by dyspnoea. Depressive symptoms were explained by both dyspnoea and reduced exercise capacity.Conclusion
The BODE index is superior to the GOLD classification for explaining anxious and depressive symptoms in COPD patients. These psychological consequences of the disease may play a role in future classification systems of COPD. 相似文献67.
MT Butcher JW Hermanson NG Ducharme LM Mitchell LV Soderholm JE Bertram 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2009,152(1):100-114
The forelimb digital flexors of the horse display remarkable diversity in muscle architecture despite each muscle-tendon unit having a similar mechanical advantage across the fetlock joint. We focus on two distinct muscles of the digital flexor system: short compartment deep digital flexor (DDF(sc)) and the superficial digital flexor (SDF). The objectives were to investigate force-length behavior and work performance of these two muscles in vivo during locomotion, and to determine how muscle architecture contributes to in vivo function in this system. We directly recorded muscle force (via tendon strain gauges) and muscle fascicle length (via sonomicrometry crystals) as horses walked (1.7 m s(-1)), trotted (4.1 m s(-1)) and cantered (7.0 m s(-1)) on a motorized treadmill. Over the range of gaits and speeds, DDF(sc) fascicles shortened while producing relatively low force, generating modest positive net work. In contrast, SDF fascicles initially shortened, then lengthened while producing high force, resulting in substantial negative net work. These findings suggest the long fibered, unipennate DDF(sc) supplements mechanical work during running, whereas the short fibered, multipennate SDF is specialized for economical high force and enhanced elastic energy storage. Apparent in vivo functions match well with the distinct architectural features of each muscle. 相似文献
68.
Pérez-Zaballos FJ Ortega-Mora LM Alvarez-García G Collantes-Fernández E Navarro-Lozano V García-Villada L Costas E 《The Journal of parasitology》2005,91(3):507-510
Neospora caninum, a recently recognized protozoan parasite of animals, is considered to be a major cause of bovine abortion worldwide. Although its life cycle is not completely known, recent studies suggest that the sexual stage occurs in dogs. The prevalence of sexual reproduction in N. caninum, however, is unknown. We investigated the ability of 3 N. caninum isolates (NC-1, NC-SweB1, and NC-Liverpool) to propagate asexually for approximately 250 parasite generations in a cell line in which they had not been cultured previously. The malthusian parameter of fitness was estimated for each isolate from 10 independent replicates of tachyzoites at the beginning as well as at the end of the experimental period. Derived and ancestral values for mean fitness were compared both within and among NC-1, NC-SweB1, and NC-Liverpool isolates. Results showed a significant increase in mean fitness for the 3 N. caninum isolates at the end of the experimental period. These findings indicate that N. caninum can adapt to new environmental conditions without the help of sexual recombination, supporting the idea that this parasite has, at least potentially, the capacity for maintaining clonal propagation in nature. 相似文献
69.
Yonekawa H; Moriwaki K; Gotoh O; Miyashita N; Matsushima Y; Shi LM; Cho WS; Zhen XL; Tagashira Y 《Molecular biology and evolution》1988,5(1):63-78
The Japanese mouse, Mus musculus molossinus, has long been considered an
independent subspecies of the house mouse. A survey of restriction- site
haplotypes of mitochondrial DNA (mtDNA) showed that Japanese mice have two
main maternal lineages. The most common haplotype is closely related to the
mtDNA of the European subspecies M. m. musculus. The other common haplotype
and two minor ones are closely related to each other and to the mtDNA of an
Asiatic subspecies, M. m. castaneus. Two other rare variants are probably
the result of recent contamination by European M. m. domesticus. The
musculus type of mtDNA is found in the southern two-thirds of Japan,
whereas the common castaneus type is found in the northern third and the
minor variants are found sporadically throughout Japan. The castaneus mtDNA
lineage had a few minor variants, whereas the musculus lineage was
completely monomorphic. By contrast, the native population of M. m.
castaneus and the Chinese and Korean musculus populations were highly
polymorphic. These results suggest that M. m. molossinus is a hybrid
between ancestral colonies, possibly very small, of M. m. musculus and M.
m. castaneus, rather than an independent subspecies.
相似文献
70.
David Arranz-Solís Javier Regidor-Cerrillo Sebastian Lourido Luis Miguel Ortega-Mora Jeroen P.J. Saeij 《International journal for parasitology》2018,48(8):597-600
Herein we describe, to our knowledge for the first time the use of the clustered regularly interspaced short palindromic repeats/CRISPR-associated gene 9 (CRISPR/Cas9) system for genome editing of Neospora caninum, an apicomplexan parasite considered one of the main causes of abortion in cattle worldwide. By using plasmids containing the CRISPR/Cas9 components adapted to the closely related parasite Toxoplasma gondii, we successfully knocked out a green fluorescent protein (GFP) in an Nc-1 GFP-expressing strain, and efficiently disrupted the NcGRA7 gene in the Nc-Spain7 isolate by insertion of a pyrimethamine resistance cassette. The successful use of this technology in N. caninum lays the foundation for an efficient, targeted gene modification tool in this parasite. 相似文献