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51.
A Osuna G Ortega F Gamarro S Castanys L M Ruiz-Perez 《International journal for parasitology》1985,15(2):167-170
Results are presented on the effects of human lymphoblastoid interferon (HUIFN-α-ly) on the infectivity of metacyclic culture forms of Trypanosoma cruzi in HeLa cells. When cells were pretreated with interferon the parasitisation ratios of the cultures increased with respect to controls. This phenomenon also occurs when interferon was added during the period of parasite-cell interaction. When parasites were pretreated with interferon but cells were not, no increase in the parasitisation ratios was observed. 相似文献
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Sunlight is a key environmental factor in almost all ecosystems, and it is necessary for many physiological functions. Many vertebrates require ultraviolet (UV) radiation to perform different physiological processes. Artificial light is used to supplement UV in captive animals, through appropriate photoperiods and UV wavelengths. Previous studies reported that repeated exposure to artificial UV radiation may cause damage to the immune system. Taking into account the importance of UV effects and the serum complement system, the relationship between them was investigated. The study lasted 90 days and was carried out in plastic chambers. Ninety six broad‐snouted caiman (C. latirostris) were assigned to four treatment groups with two replicates each: total darkness (TD), 8 hr per day (8 hr) and 16 hr per day (16 hr) of artificial UV/visible light exposure, and normal photoperiod of natural light (NP). Snout–vent length was measured to determine animal growth. Hemolytic assays were performed to evaluate the effects of artificial UV/visible light, TD, and NP on the serum complement system. Results showed that animals grew more in the NP group. The capacity of C. latirostris serum to hemolyze sheep red blood cells was higher in the NP group than when they are maintained in constant light–dark cycles (8 and 16 hr) or in TD. These data demonstrate that artificial UV should be considered as a potential hazard for captive crocodilians if it is not properly managed, and this should be taken into account in the general design of facilities for reptilian husbandry. Zoo Biol 31:523‐533, 2012. © 2011 Wiley Periodicals, Inc. 相似文献
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Francesco Pantano Matteo Santoni Giuseppe Procopio Mimma Rizzo Roberto Iacovelli Camillo Porta Alessandro Conti Antonio Lugini Michele Milella Luca Galli Cinzia Ortega Francesco Maria Guida Marianna Silletta Giovanni Schinzari Elena Verzoni Daniela Modica Pierfilippo Crucitti Annamaria Rauco Alessandra Felici Valentina Ballatore Stefano Cascinu Giuseppe Tonini Giacomo Carteni Antonio Russo Daniele Santini 《PloS one》2015,10(4)
Background
Everolimus is a mammalian target of rapamycin (mTOR) inhibitor approved for the treatment of metastatic renal cell carcinoma (mRCC). We aimed to assess the association between the baseline values and treatmentrelated modifications of total serum cholesterol (C), triglycerides (T), body mass index (BMI), fasting blood glucose level (FBG) and blood pressure (BP) levels and the outcome of patients treated with everolimus for mRCC.Methods
177 patients were included in this retrospective analysis. Time to progression (TTP), clinical benefit (CB) and overall survival (OS) were evaluated.Results
Basal BMI was significantly higher in patients who experienced a CB (p=0,0145). C,T and C+T raises were significantly associated with baseline BMI (p=0.0412, 0.0283 and 0.0001). Median TTP was significantly longer in patients with T raise compared to patients without T (10 vs 6, p=0.030), C (8 vs 5, p=0.042) and C+T raise (10.9 vs 5.0, p=0.003). At the multivariate analysis, only C+T increase was associated with improved TTP (p=0.005). T raise (21.0 vs 14.0, p=0.002) and C+T increase (21.0 vs 14.0, p=0.006) were correlated with improved OS but were not significant at multivariate analysis.Conclusion
C+T raise is an early predictor for everolimus efficacy for patients with mRCC. 相似文献55.
Studies were performed to define tissue culture techniques and culture conditions for morphogenesis, callus culture and plantlet culture of sweet orange (Citrus sinensis (L.) Osb.), citron (C. medica L.) and lime (C. aurantifolia) (Christm. Swing). The optimal concentrations of NAA to induce root formation on stem segments were 10 mg l-1 for sweet orange and lime, and 3 mg l-1 for citron. The optimal BA concentration for shoot and bud proliferation was 3 mg l-1 for sweet orange and citron, and 1 mg l-1 for lime. Callus initiation was accomplished in a culture medium containing 10 mg l-1 NAA and 0.25 mg l-1 BA. Callus was maintained by periodical subculture into the same medium supplemented with 10% (v:v) organge juice. In vitro plantlets of the three species were obtained by rooting of shoots developed from bud cultures, and of citron and lime by development of shoots from root cultures. The plants were successfully established on soil. 相似文献
56.
Length‐weight relationship for sea catfishes (Siluriformes: Ariidae) from the southeastern Gulf of California with new records on maximum length 下载免费PDF全文
D. S. Palacios‐Salgado J. R. Flores‐Ortega O. I. Zavala‐Leal J. Granados‐Amores J. T. Nieto‐Navarro R. Tapia‐Varela J. M. J. Ruiz‐Velazco X. G. Moreno‐Sánchez M. A. Cadena‐Roa 《Zeitschrift fur angewandte Ichthyologie》2018,34(3):700-702
The parameters of length‐weight relationship (LWR) are presented for seven species of catfish from the southeastern Gulf of California. Samples were obtained every three months, in Bahia de Matanchen (using bottom trawl nets consistent of 72 hauls, with mesh sizes of 3.2 cm in the wings and 2.54 cm in the cod‐end) from February to November, 2016 and in the San Blas estuarine system (using gill nets consistent of 32 hauls, with mesh sizes of 5 cm) from August, 2015 to May, 2016 respectively. The allometric coefficient (b) of LWR varied from 2.797 for the Cominate Sea Catfish (Occidentarius platypogon (Günther, 1864)) to 3.373 for the Tete Sea Catfish (Ariopsis gilberti (Jordan & Williams, 1895)). Four species reached new records on maximum total length (Tete Sea Catfish, A. gilberti; Widehead Sea Catfish, A. guatemalensis (Günther, 1864); Conguito Sea Catfish, Cathorops liropus (Bristol, 1897); and Curator Sea Catfish, C. raredonae Marceniuk, Betancur‐R, & Acero, 2009). For six of these species this accounts for the first report on estimations of LWR parameters. 相似文献
57.
Substantia nigra dopaminergic neurons and striatal interneurons are engaged in three parallel but interdependent postnatal neurotrophic circuits 下载免费PDF全文
Clara Ortega‐de San Luis Manuel A. Sanchez‐Garcia Jose Luis Nieto‐Gonzalez Pablo García‐Junco‐Clemente Adoracion Montero‐Sanchez Rafael Fernandez‐Chacon Alberto Pascual 《Aging cell》2018,17(5)
The striatum integrates motor behavior using a well‐defined microcircuit whose individual components are independently affected in several neurological diseases. The glial cell line‐derived neurotrophic factor (GDNF), synthesized by striatal interneurons, and Sonic hedgehog (Shh), produced by the dopaminergic neurons of the substantia nigra (DA SNpc), are both involved in the nigrostriatal maintenance but the reciprocal neurotrophic relationships among these neurons are only partially understood. To define the postnatal neurotrophic connections among fast‐spiking GABAergic interneurons (FS), cholinergic interneurons (ACh), and DA SNpc, we used a genetically induced mouse model of postnatal DA SNpc neurodegeneration and separately eliminated Smoothened (Smo), the obligatory transducer of Shh signaling, in striatal interneurons. We show that FS postnatal survival relies on DA SNpc and is independent of Shh signaling. On the contrary, Shh signaling but not dopaminergic striatal innervation is required to maintain ACh in the postnatal striatum. ACh are required for DA SNpc survival in a GDNF‐independent manner. These data demonstrate the existence of three parallel but interdependent neurotrophic relationships between SN and striatal interneurons, partially defined by Shh and GDNF. The definition of these new neurotrophic interactions opens the search for new molecules involved in the striatal modulatory circuit maintenance with potential therapeutic value. 相似文献
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Xiaodan Ni Joseph H. Davis Nikhil Jain Aida Razi Samir Benlekbir Andrew G. McArthur John L. Rubinstein Robert A. Britton James R. Williamson Joaquin Ortega 《Nucleic acids research》2016,44(17):8442-8455
YphC and YsxC are GTPases in Bacillus subtilis that facilitate the assembly of the 50S ribosomal subunit, however their roles in this process are still uncharacterized. To explore their function, we used strains in which the only copy of the yphC or ysxC genes were under the control of an inducible promoter. Under depletion conditions, they accumulated incomplete ribosomal subunits that we named 45SYphC and 44.5SYsxC particles. Quantitative mass spectrometry analysis and the 5–6 Å resolution cryo-EM maps of the 45SYphC and 44.5SYsxC particles revealed that the two GTPases participate in the maturation of the central protuberance, GTPase associated region and key RNA helices in the A, P and E functional sites of the 50S subunit. We observed that YphC and YsxC bind specifically to the two immature particles, suggesting that they represent either on-pathway intermediates or that their structure has not significantly diverged from that of the actual substrate. These results describe the nature of these immature particles, a widely used tool to study the assembly process of the ribosome. They also provide the first insights into the function of YphC and YsxC in 50S subunit assembly and are consistent with this process occurring through multiple parallel pathways, as it has been described for the 30S subunit. 相似文献