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991.
Sonia León-Cabrera Blanca E. Callejas Yadira Ledesma-Soto Jossimar Coronel Carlos Pérez-Plasencia Emma B. Gutiérrez-Cirlos Federico ávila-Moreno Miriam Rodríguez-Sosa Rogelio Hernández-Pando Brenda Marquina-Castillo Yolanda I. Chirino Luis I. Terrazas 《International journal of biological sciences》2014,10(9):948-956
Colitis-associated colorectal cancer (CAC) is one of the most common cancers and is closely related to chronic or deregulated inflammation. Helminthic infections can modulate inflammatory responses in some diseases, but their immunomodulatory role during cancer development remains completely unknown. We have analyzed the role of Taenia crassiceps-induced anti-inflammatory response in determining the outcome of CAC. We show that extraintestinal T. crassiceps infection in CAC mice inhibited colonic inflammatory responses and tumor formation and prevented goblet cell loss. There was also increased expression of IL-4 and alternatively activated macrophages markers in colonic tissue and negative immunomodulation of pro-inflammatory cytokine expression. In addition, T. crassiceps infection prevented the upregulation of β-catenin and CXCR2 expression observed in the CAC mice, which are both markers associated with CAC-tumorigenesis, and reduced the numbers of circulating and colonic CD11b+Ly6ChiCCR2+ monocytes. Thus, immunomodulatory activities induced by helminth infections may have a role in the progression of CAC. 相似文献
992.
Julio Villatoro-Hernandez Maria J Loera-Arias Anali Gamez-Escobedo Moises Franco-Molina Jorge G Gomez-Gutierrez Humberto Rodriguez-Rocha Yolanda Gutierrez-Puente Odila Saucedo-Cardenas Jesus Valdes-Flores Roberto Montes-de-Oca-Luna 《Microbial cell factories》2008,7(1):22
Background
Chemokines are a large group of chemotactic cytokines that regulate and direct migration of leukocytes, activate inflammatory responses, and are involved in many other functions including regulation of tumor development. Interferon-gamma inducible-protein-10 (IP-10) is a member of the C-X-C subfamily of the chemokine family of cytokines. IP-10 specifically chemoattracts activated T lymphocytes, monocytes, and NK cells. IP-10 has been described also as a modulator of other antitumor cytokines. These properties make IP-10 a novel therapeutic molecule for the treatment of chronic and infectious diseases. Currently there are no suitable live biological systems to produce and secrete IP-10. Lactococcus lactis has been well-characterized over the years as a safe microorganism to produce heterologous proteins and to be used as a safe, live vaccine to deliver antigens and cytokines of interest. Here we report a recombinant strain of L. lactis genetically modified to produce and secrete biologically active IP-10. 相似文献993.
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997.
Diet composition, niche measures, and prey consumption of three sympatric species of carnivores, one non-native and introduced,
the American minkNeovison vison Schreber, 1777, and two native, the spotted genetGenetta genetta Linnaeus, 1758 and the Eurasian otterLutra lutra Linnaeus, 1758, were studied in a Spanish Mediterranean area. The study was based on the analysis of prey remains in the
faeces of the predators. Faeces of mink (n = 444), genet (n = 310), and otter (n = 108) were collected all year round for four years along the Llobregat (21 km) and Gavarresa rivers (12 km). Simultaneously,
and in the same area, prey species density and weight were estimated by means of trapping. The diet of mink and genet was
dominated by the American crayfishProcambarus clarkii, while the otter fed almost exclusively on fish. Compared to the mink, the genet seemed to specialise more on small mammals
while the mink specialised more on aquatic birds, especially in autumn-winter. Niche overlap was higher between mink and genet
than between either of them and the otter. 相似文献
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999.
Emily Sancha Yolanda van Heezik Richard Maloney Maurice Alley Philip Seddon 《Zoo biology》2004,23(1):1-13
A significant increase in hatching and late‐incubation deaths during two breeding seasons in a captive population of endangered black stilts (kaki, Himantopus novaezelandiae) prompted an investigation into the potential role of iodine deficiency. During the 1997 and 1998 breeding seasons, the survival rate of captive‐laid eggs during artificial incubation and hatching was lower than that of eggs laid by wild kaki, which were collected and incubated artificially in the same environment. Necropsy results revealed abnormalities in thyroid structure. These abnormalities had been occurring in captive birds since 1994, but they peaked in 1997 and 1998 at 30% and 81%, respectively, of all diagnosed necropsies. Necropsies of pied stilts, hybrids, and one kaki from the wild revealed no thyroid abnormalities. Gross morphological symptoms observed at hatching in chicks that died were consistent with those described for iodine deficiency in poultry. Serum levels of thyroxine (T4) were considerably higher in wild pied stilts and hybrid chicks than in captive adult, subadult, and kaki chicks. In five individuals from the captive population, serum levels increased after about 160 days of iodine supplementation and approached values in the wild. The constraints associated with working with such a critically endangered species (e.g., small sample size and an urgent need to effect changes) precluded the use of an experimental approach to determine the role iodine deficiency played in peri‐hatching deaths. However, we believe the evidence presented here strongly supports a case for the impact of iodine on survival within the captive population. Our experience also highlights the need for vigilance in captive programs with respect to potential dietary deficiencies when endangered species are raised in captivity for conservation purposes. Zoo Biol 23:1–13, 2004. © 2004 Wiley‐Liss, Inc. 相似文献
1000.
S. Patricia Stock Benjamin Rivera-Orduño Yolanda Flores-Lara 《Journal of invertebrate pathology》2009,100(3):175-184
A new Heterorhabditis species was isolated from nymphal stages of the seasonal cicada Diceroprocta ornea (Walker) in an asparagus field in the state of Sonora, Mexico. Concomitantly, another isolate of the same nematode species was also collected from an oak woodland habitat in the Chiricahua mountain range in southeastern Arizona. Morphological and molecular studies together with cross-hybridization tests indicate these two isolates are conspecific and represent a new undescribed Heterorhabditis sp. This new species is distinguished from other species in this genus by a combination of several qualitative and quantitative morphological traits. Key diagnostic features include: presence of a pronounced post-anal swelling in the hermaphrodite; male with nine pairs of bursal rays, with pairs 4 and 7 bent outwards and one pair of papillae placed on the cloacal opening, value of D% (average: 79); infective juveniles with a well developed cuticular tooth, long tail (average: 105 μm) and values of D% (average: 90) and E% (average: 99). In addition to these diagnostic characters, cross-hybridization tests between the new species with H. bacteriophora and H. mexicana yielded no fertile progeny. Comparison of ITS rDNA sequences with other available sequences of described species depicted the two isolates as a new species. Phylogenetic analysis of these sequence data placed H. sonorensis n. sp. as a member of the indica-group. 相似文献