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1.
Mattiucci S Paoletti M Olivero-Verbel J Baldiris R Arroyo-Salgado B Garbin L Navone G Nascetti G 《Systematic parasitology》2008,69(2):101-121
Contracaecum bioccai n. sp. is described from the brown pelican Pelecanus occidentalis (L.) in northern Colombia (Totumo Marsh) based on 20 enzyme loci studied using multilocus allozyme electrophoresis. Moreover, genetic relationships between the new taxon and related congeners are presented based on allozyme data-sets and sequence analyses (519 bp) of the mtDNA-cox2 gene. Fixed allele differences were found at some of the allozyme loci analysed in comparison with other Contracaecum spp. from pelicans and cormorants [i.e. the sibling species of the C. rudolphii Hartwich, 1964 complex, C. septentrionale Kreis, 1955, C. micropapillatum (Stossich, 1890), C. microcephalum (Rudolphi, 1809) and C. pelagicum Johnston & Mawson, 1942]. The genetic distance, at the allozyme level, between C. bioccai n. sp. and its congeners ranged from D ( Nei ) = 0.80 versus C. septentrionale to D ( Nei ) = 1.40 versus C. micropapillatum. The genetic distance at the mtDNA cox-2 level ranged, on average, from K-2P = 0.12 versus the C. rudolphii species complex to K-2P = 0.15 versus C. micropapillatum. An overall concordant tree topology, obtained from UPGMA and NJ tree analyses inferred from allozyme data, as well as from MP, UPGMA and NJ inferred from mtDNA-cox2 sequence analysis, showed C. bioccai n. sp. as a separated lineage to the other Contracaecum spp. A concordant result was also obtained by PCA analysis based on both the allozyme and mtDNA cox-2 data-sets. All of the tree topologies, derived from the phylogenetic analysis inferred from both allozymes and mtDNA data-sets, were in substantial agreement and depicted C. bioccai as closely related to the sibling species of the C. rudolphii complex (C. rudolphii A and C. rudolphii B) and C. septentrionale. Morphological analysis and a differential diagnosis based on male specimens of C. bioccai, which had been genetically characterised by both allozyme markers and mtDNA sequences analysis with respect to morphologically related congeners, enabled the detection of differences in a numbers of characters, including spicule length, the morphology of the distal end of the spicule and the distribution patterns of the distal caudal papillae. 相似文献
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Cyclooxygenases (cox) are potent mediators of inflamation and two cox-izoenzymes, cox-1, cox-2, are described to date. Cox-2 is cytokine-inducible in inflammatory cells and enhanced cox-2 expression has been attributed a key role in the development of edema and immunomodulation in pathologically altered brain tissues. In normal cerebral cortex cox-2 is present only in neurons, but not in the glial or vascular endothelial cells. The function of microglia in glioma biology is unclear. Microglia have both neurotrophic and neurotoxic functions and have been shown to release a variety of cytokines. Our preliminary results showed that the expression pattern of cox-2 is predominantly neuronal although glial expression was observed with the correlation of high malignancy. In this study we aimed to assess the phenotypes (astrocyte, microglia) of the cox-2-expressing glial cells in various types of human gliomas and to compare their expression patterns. For this purpose we employed dual immunohistochemistry for cox-2 and GFAP (astrocyte) or LCA-MAC (microglia-macrophage) in archival formalin-fixed, paraffin embedded human tissue diagnosed as oligodendroglioma and/or astrocytoma. The results showed that cox-2 immunoreactivity is up-regulated in the neurons according to the tumor grade. Most of the cox-2 immunoreactive glia were GFAP-positive in anaplastic oligodendrogliomas and at lesser extend in glioblastomas. Cox-2 and LCA co-localization was detected in more glial cells in glioblastomas. It may be speculated that the induction of cox-2 in microglia may contribute to the deleterious effects of prostanoids in cerebral edema formation during the progression of oligodendrogliomas. The detection of cox-2 in astrocytes surrounding the necrotic areas might be important to develop new strategies, such as the usage of cox-2 inhibitors combine with chemotherapy and radiotherapy in the treatment of glioma patients. 相似文献
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Inhibition of cyclooxygenase-2 (cox-2) is considered to be anti-inflammatory, whereas inhibition of the constitutive isozyme cox-1 causes renal and gastrointestinal toxicity. Therefore, to achieve an optimal anti-inflammatory effect, an inhibitor should be cox-2 selective without inhibiting cox-1. For this purpose, 10 different cox-2-selective phosphorothioated oligonucleotides (S-oligos) were tested to inhibit the cox-2 enzyme selectively in vivo. An aqueous solution of these S-oligos (3 mg/kg body weight) was injected intraperitoneally (i.p.) into male Sprague-Dawley rats with colitis induced by trinitrobenzene sulfonic acid (TNBS). The colonic levels of cox-2 protein, mRNA, myeloperoxidase (MPO), and prostaglandin E2 (PGE2) were increased significantly on day 1 and remained significantly elevated until day 7 post-TNBS administration, whereas cox-1 remained unaltered. Two S-oligos were found to be effective in reducing the level of cox-2 protein selectively without any effect on the cox-1. The effective S-oligo, but not the mismatched control oligo, reduced the tissue levels of PGE2 and MPO activity significantly. The effective S-oligo reduced the level of cox-2 but not the cox-1 mRNA significantly, whereas a mismatched or a sense control oligo did not affect the levels of these isoforms. M-fold analysis demonstrated extensive secondary structure formation in the cox-2 mRNA. These findings demonstrate that only a few selected sites in the cox-2 target mRNA are accessible in vivo, probably because of the presence of secondary structures. Suppression of cox-2 protein, PGE2, and MPO activity by the S-oligo might prove to be an anti-inflammatory property. 相似文献
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DiBernardi L Doré M Davis JA Owens JG Mohammed SI Guptill CF Knapp DW 《Prostaglandins, leukotrienes, and essential fatty acids》2007,76(4):245-250
Oral squamous cell carcinoma (OSCC) is associated with high morbidity and mortality. A potential target for OSCC treatment is cyclooxygenase-2 (cox-2). Pet cats with naturally occurring OSCC may offer the opportunity to study anticancer activity of cox inhibitors. Cox-2 expression in feline OSCC was determined by immunohistochemistry. High intensity cox-2 immunoreactivity was detected in 6 of 34 (18%) feline OSCC samples. Weak immunoreactivity was noted in 22 OSCCs and in epithelial cells from oral mucosa of clinically normal cats. Pharmacokinetics of a cox inhibitor (piroxicam, 0.3 mg/kg) were studied in carcinoma-bearing cats to confirm a dose for follow-up trials. The average peak serum piroxicam concentration (948 ng/ml, which inhibited cox-2 activity) and serum half-life (15.9 h) were similar to that in normal cats. These results provide information (cox-2 expression as an inclusion criteria, 0.3 mg/kg daily piroxicam) for the design of follow-up trials of cox inhibitor treatment in pet cats with OSCC. 相似文献
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F Nuttinck P Reinaud H Tricoire C Vigneron N Peynot J P Mialot P Mermillod G Charpigny 《Molecular reproduction and development》2002,61(1):93-101
Prostaglandins could be involved in various aspects of final differentiation of ovarian follicles. Prostaglandins are generated by the cyclooxygenase (cox) pathway. Until now, the expression pattern of isoforms cox-1 and cox-2 of cyclooxygenase in bovine cumulus-oocyte complexes (COCs) was unknown. Using immunodetection procedure, we demonstrated in the present study that cox-2 was expressed by cumulus cells during in vivo and in vitro maturation. Time course induction of cox-2 expression was investigated during in vitro maturation using Western blot analysis. Specific signal of cox-2 was markedly evidenced from 6 hr of culture and increased to reach a maximal level at 24 hr of culture. In vitro, cox-2 expression in COCs was associated with increased concentrations of PGE(2) and PGF(2alpha) in the maturation medium. In addition, the effects of culture conditions on cox-2 expression was considered using RT-PCR and Western-blot analysis. We demonstrated that the addition of 10 ng/ml of EGF to TCM199 clearly increased the expression level of cox-2 mRNA and protein. Higher levels of in vitro cox-2 expression was associated with greater rates of cumulus expansion and oocytes at metaphase II at 24 hr of culture. In conclusion, our present results suggest that cox-2 expression in cumulus cells may be involved in differentiation of COCs that occurs during oocyte maturation. 相似文献
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Garbin L Mattiucci S Paoletti M González-Acuña D Nascetti G 《The Journal of parasitology》2011,97(3):476-492
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Mutsaers AJ Mohammed SI DeNicola DB Snyder PW Glickman NW Bennett PF de Gortari AE Bonney PL Knapp DW 《Prostaglandins, leukotrienes, and essential fatty acids》2005,72(3):181-186
The purpose of this study was to determine the extent to which pretreatment prostaglandin E2 (PGE2) concentration and cyclooxygenase-2 (cox-2) expression could be used to predict the antitumor activity of cox inhibitor treatment in naturally occurring canine transitional cell carcinoma of the urinary bladder (TCC). Snap frozen tissues (to measure PGE2) and formalin-fixed TCC samples (for cox-2 immunohistochemistry) were obtained by cystoscopy or surgery. Complete tumor staging was performed before and after one month of treatment with the cox inhibitor, piroxicam (0.3 mg/kg q24 h po). The pretreatment PGE2 concentration ranged from 57 to 1624 ng/g of TCC tissue; n=18 dogs). Cox-2 immunoreactivity was observed in all TCC samples. There was no association between PGE2 concentration, cox-2 expression, and change in tumor volume with piroxicam treatment. In conclusion, cox-2 expression or PGE2 concentration alone, or the combination of the two was not useful in predicting response to piroxicam treatment in canine TCC. 相似文献
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CARL A. BEAM ROSA-MARIA PREPARATA MARION HIMES DAVID L. NANNEY 《The Journal of eukaryotic microbiology》1993,40(5):660-667
ABSTRACT. Sixty-five members of the Ctypthecodinium cohnii species complex were analyzed for sequence differences within the D2 region of the 23S ribosomal RNA molecule. On the basis of 46 sequence differences the strains fell into 19 distinct ribosets (strains of identical sequence), some with many members. Members of four of the seven major sibling species (widespread breeding groups) were each found within single ribosets. Members of three other major sibling species were each, however, divided into two ribosets by a single sequence difference correlated with geographic separation and with previously reported electrophoretic polymorphisms of soluble enzymes within the sibling species. In addition to members of major sibling species, some ribosets include many minor sibling species (each represented by only one strain). Of 38 minor sibling species, 22 shared sequence with a major sibling species. Of these 22, 14 were identical in soluble enzymes to their related major sibling species or differed by only one of three enzymes. Other minor sibling species appear to have diverged extensively from any others in both rRNA sequence and electrophoretic profile. As a group, major sibling species differ markedly in the number of minor sibling species associated with them, suggesting differences in frequency of sexually isolating events in their past histories. These findings are discussed in the context of the previously proposed model of sympatric speciation. 相似文献
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Eighty-seven axenic clones of the colorless inshore dinoflagellate Crypthecodinium cohnii were found by mating experiments to fall into 52 sibling species, seven wide ranging (two possibly global)—called major sibling species—and 45 found only once—minor sibling species. Electrophoretic analysis of three soluble enzymes from these strains revealed the following: 1) Despite some polymorphism most members of major sibling species closely resemble one another electrophoretically. 2) Major sibling species and most minor ones are electrophoretically distinct. 3) Sharing of electromorphs is sufficiently extensive, however, that no major sibling species is totally unrelated to all others. 4) Some minor sibling species are electrophoretically indistinguishable from a member of a major sibling species or from one another, suggesting recent origin by sexual isolation in situ. 5) Other minor sibling species differ from majors by one, two, or all three of the enzymes studied. A “model” of sexual isolation and diversification is offered. 相似文献
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Miska KB Schwarz RS Jenkins MC Rathinam T Chapman HD 《The Journal of parasitology》2010,96(5):982-986
In order to determine the evolutionary relationships among Eimeria species that parasitize birds of the Galliformes, the 18s rDNA gene and a portion of the cytochrome oxidase subunit 1 (cox-1) were amplified from Eimeria species isolated from turkeys, chukars, and pheasants. The phylogenetic analysis of these sequences suggests that species infecting chickens are polyphyletic and, therefore, do not all share a direct common ancestor. Both the 18s rDNA and the cox-1 sequences indicate that Eimeria tenella and Eimeria necatrix are more closely related to Eimeria of turkeys and pheasants than to other species that infect the chicken. It is, therefore, likely that the chicken Eimeria spp. represent 2 separate ancestral colonizations of the gut, one of which comprises E. tenella and E. necatrix that infect the ceca, while the other includes Eimeria acervulina, Eimeria brunetti, Eimeria maxima, and Eimeria mitis, which infect the upper regions of the intestine. 相似文献
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Derua YA Alifrangis M Hosea KM Meyrowitsch DW Magesa SM Pedersen EM Simonsen PE 《Malaria journal》2012,11(1):188
ABSTRACT: BACKGROUND: A dramatic decline in the incidence of malaria due to Plasmodium falciparum infection in coastal East Africa has recently been reported to be paralleled (or even preceded) by an equally dramatic decline in malaria vector density, despite absence of organized vector control. As part of investigations into possible causes for the change in vector population density, the present study analysed the Anopheles gambiae s.l. sibling species composition in north-eastern Tanzania. METHODS: The study was in two parts. The first compared current species complex composition in freshly caught An. gambiae s.l. complex from three villages to the composition reported from previous studies carried out 2-4 decades ago in the same villages. The second took advantage of a sample of archived dried An. gambiae s.l. complex specimens collected regularly from a fourth study village since 2005. Both fresh and archived dried specimens were identified to sibling species of the An. gambiae s.l. complex by PCR. The same specimens were moreover examined for Plasmodium falciparum and Wuchereria bancrofti infection by PCR. RESULTS: As in earlier studies, An. gambiae s.s., Anopheles merus and Anopheles arabiensis were identified as sibling species found in the area. However, both study parts indicated a marked change in sibling species composition over time. From being by far the most abundant in the past An. gambiae s.s. was now the most rare, whereas An. arabiensis had changed from being the most rare to the most common. P. falciparum infection was rarely detected in the examined specimens (and only in An. arabiensis) whereas W. bancrofti infection was prevalent and detected in all three sibling species. CONCLUSION: The study indicates that a major shift in An. gambiae s.l. sibling species composition has taken place in the study area in recent years. Combined with the earlier reported decline in overall malaria vector density, the study suggests that this decline has been most marked for An. gambiae s.s., and least for An. arabiensis, leading to current predominance of the latter. Due to differences in biology and vectorial capacity of the An. gambiae s.l. complex the change in sibling species composition will have important implications for the epidemiology and control of malaria and lymphatic filariasis in the study area. 相似文献
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Mohammed SI Khan KN Sellers RS Hayek MG DeNicola DB Wu L Bonney PL Knapp DW 《Prostaglandins, leukotrienes, and essential fatty acids》2004,70(5):479-483
The purpose of this work was to determine cox-1 and cox-2 expression by immunohistochemistry in forms of naturally occurring canine cancer in order to identify animal systems for pre-clinical evaluation of cox inhibitors and cox-2 inhibitors in cancer. Canine lymphoma (LSA), prostatic carcinoma (PCA), osteosarcoma (OSA), oral melanoma (MEL), oral squamous cell carcinoma (SCC), oral fibrosarcoma (FSA), mammary carcinoma (MCA), and normal tissues were included. Cox-2 was expressed in epithelial tumors (17 of 26 SCC, 8 of 13 MCA, 5 of 9 PCA cases) and MEL (9 of 15 cases), but was generally absent in normal tissues. Cox-2 expression was minimal or absent in mesenchymal tumors and LSA. Cox-1 was expressed in normal epithelial tissues and in some osteoclast and osteoblast in bone, but was absent in normal lymph node. In conclusion, forms of canine cancer were identified for in vivo studies of the effects of cox inhibitors and selective cox-2 inhibitors on cancer. 相似文献
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D'Amelio S Mathiopoulos KD Santos CP Pugachev ON Webb SC Picanço M Paggi L 《International journal for parasitology》2000,30(2):223-226
Polymerase-chain-reaction-based restriction fragment length polymorphism analysis was performed to establish genetic markers in rDNA, for the identification of the three sibling species of the Anisakis simplex complex and morphologically differentiated Anisakis species, i.e. Anisakis physeteris, Anisakis schupakovi, Anisakis typica and Anisakis ziphidarum. Different restriction patterns were found between A. simplex sensu stricto and Anisakis pegreffii with two of the restriction endonucleases used (HinfI and TaqI), between A. simplex sensu stricto and A. simplex C with one endonuclease (HhaI), and between A. simplex C and Aniskis pegreffii with three endonucleases (HhaI, HinfI and TaqI), while no variation in patterns was detected among individuals within each species. The species A. physeteris, A. schupakovi, A. typica and A. ziphidarum were found to be different from each other and different from the three sibling species of the A. simplex complex by distinct fragments using 10-12 of the endonucleases tested. The polymorphisms obtained by restriction fragment length polymorphisms have provided a new set of genetic markers for the accurate identification of sibling species and morphospecies. 相似文献