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71.
Federica Marchesi Lorenzo Piemonti Alberto Mantovani Paola Allavena 《Cytokine & growth factor reviews》2010,21(1):77-82
Invasion and metastasis are key components of cancer progression. Inflammatory mediators, including cytokines and chemokines, can facilitate tumor dissemination. A distinct and largely forgotten path is perineural invasion (PNI), defined as the presence of cancer cells in the perinerium space. PNI is frequently used by many human carcinomas, in particular by pancreas and prostate cancer, and is associated with tumor recurrence and pain in advanced patients. Neurotrophic factors have been identified as molecular determinants of PNI. A role for chemokines in this process has been proposed; the chemokine CX3CL1/Fractalkine attracts receptor positive pancreatic tumor cells to disseminate along peripheral nerves. Better understanding of the neurotropism of malignant cells and of the clinical significance of PNI would help the design of innovative strategies for the control of tumor dissemination and pain in cancer patients. 相似文献
72.
Cecília Rodrigues Vieira Maria Carolina Blassioli Moraes Miguel Borges Edison Ryoiti Sujii Raúl Alberto Laumann 《Biological Control》2013,64(1):75-82
In many plants, the secondary metabolite cis-jasmone activates the metabolic pathway that produces volatile organic compounds attractive to natural enemies and, sometimes, repellent to herbivores. Previous studies indicate that the feeding damage caused by the herbivore Euschistus heros or the exogenous application of cis-jasmone in soybean plants induces the release of herbivore-induced plant volatiles (HIPVs) with a similar chemical profile and these compounds can attract the stink bug egg parasitoid Telenomus podisi (Scelionidae). Herein we tested in field conditions the effect of exogenous application of cis-jasmone in soybean plants on the parasitoid and stink bug community and on stink bug egg parasitism. In two areas, one within a soybean and another within a Crotalaria matrix, we randomly distributed 2 m2 plots, with soybean plants induced (treatment, n = 5) or not induced by cis-jasmone (control, n = 5) in the field. We sampled the parasitoid community weekly with yellow sticky traps (n = 3/plot) and monitored parasitism with sentinel eggs of E. heros (n = 150/plot). We also monitored the population of stink bugs weekly, by sampling each plot with shake-cloth technique. The abundance of Scelionidae was highest overall and also in treated plots during the first four weeks in the area with a soybean matrix, but decreased thereafter. The richness of parasitoid families was similar between treatment and control plots in the area with a soybean matrix, but higher in control plots in the area with a Crotalaria matrix. Evenness was higher in control plots in the area with soybean matrix, whereas the reverse occurred in the area with a Crotalaria matrix. Results suggest that treatment with cis-jasmone effectively attracted and enhanced the population of scelionid parasitoids, but had no effect on the occurrence and intensity of parasitism and in the number of stink bugs. 相似文献
73.
Francesca Pennacchietti Stefania Abbruzzetti Aba Losi Carmen Mandalari Roberta Bedotti Cristiano Viappiani Francesca Cella Zanacchi Alberto Diaspro Wolfgang G?rtner 《PloS one》2014,9(9)
We report thermal recovery kinetics of the lit state into the parental dark state, measured for the blue light-sensing photoreceptor YtvA inside overexpressing E. coli and B. subtilis bacterial cells, performed for the wild type and several mutated proteins. Recovery was followed as a recovery of the fluorescence, as this property is only found for the parental but not for the photochemically generated lit state. When cells were deposited onto a microscope glass plate, the observed thermal recovery rate in the photocycle was found ca. ten times faster in comparison to purified YtvA in solution. When the E. coli or B. subtilis colonies were soaked in an isotonic buffer, the dark relaxation became again much slower and was very similar to that observed for YtvA in solution. The observed effects show that rate constants can be tuned by the cellular environment through factors such as hydration. 相似文献
74.
75.
Peroxygenase is an enzyme that can convert a double bond to an epoxide. Peroxygenase activity from oat (Avena sativa) seeds was immobilized on synthetic membranes. The immobilized preparation was tested on oleic acid in aqueous and heptane media. The order of oxidant activity was tert-butyl hydroperoxide>cumene hydroperoxide>H2O2–Urea-H2O2. The immobilized preparation could be reused. Oleic acid was a preferred substrate compared to its trans analogue, elaidic acid. 相似文献
76.
Sequence and diversity of DRB genes of Aotus nancymaae, a primate model for human malaria parasites 总被引:3,自引:0,他引:3
Nino-Vasquez JJ Vogel D Rodriguez R Moreno A Patarroyo ME Pluschke G Daubenberger CA 《Immunogenetics》2000,51(3):219-230
The New World primate Aotus nancymaae is susceptible to infection with the human malaria parasite Plasmodium falciparum and Plasmodium vivax and has therefore been recommended by the World Health Organization as a model for evaluation of malaria vaccine candidates.
We present here a first step in the molecular characterization of the major histocompatibility complex (MHC) class II DRB genes of Aotus nancymaae (owl monkey or night monkey) by nucleotide sequence analysis of the polymorphic exon 2 segments. In a group of 15 nonrelated
animals captivated in the wild, 34 MHC DRB alleles could be identified. Six allelic lineages were detected, two of them having human counterparts, while two other lineages
have not been described in any other New World monkey species studied. As in the common marmoset, the diversity of DRB alleles appears to have arisen largely by point mutations in the β-pleated sheets and by frequent exchange of fixed sequence
motifs in the α-helical portion. Pairs of alleles differing only at amino acid position b86 by an exchange of valine to glycine
are present in Aotus, as in humans. Essential amino acid residues contributing to MHC DR peptide binding pockets number 1 and 4 are conserved
or semiconserved between HLA-DR and Aona-DRB molecules, indicating a capacity to bind similar peptide repertoires. These results support fully our using Aotus monkeys as an animal model for evaluation of future subunit vaccine candidates.
Received: 10 August 1999 / Revised: 11 October 1999 相似文献
77.
Kallyne A. Barros Alberto A. Esteves-Ferreira Masami Inaba Helena Meally John Finnan Susanne Barth Seth J. Davis Ronan Sulpice 《Plant, cell & environment》2020,43(6):1404-1420
Barley is described to mostly use sucrose for night carbon requirements. To understand how the transient carbon is accumulated and utilized in response to cold, barley plants were grown in a combination of cold days and/or nights. Both daytime and night cold reduced growth. Sucrose was the main carbohydrate supplying growth at night, representing 50–60% of the carbon consumed. Under warm days and nights, starch was the second contributor with 26% and malate the third with 15%. Under cold nights, the contribution of starch was severely reduced, due to an inhibition of its synthesis, including under warm days, and malate was the second contributor to C requirements with 24–28% of the total amount of carbon consumed. We propose that malate plays a critical role as an alternative carbon source to sucrose and starch in barley. Hexoses, malate, and sucrose mobilization and starch accumulation were affected in barley elf3 clock mutants, suggesting a clock regulation of their metabolism, without affecting growth and photosynthesis however. Altogether, our data suggest that the mobilization of sucrose and malate and/or barley growth machinery are sensitive to cold. 相似文献
78.
Ailec Ho‐Plagaro Concepcin Santiago‐Fernandez Cristina Rodríguez‐Díaz Carlos Lopez‐Gmez Sara Garcia‐Serrano Francisca Rodríguez‐Pacheco Sergio Valdes Alberto Rodríguez‐Caete Guillermo Alcaín‐Martínez Natalia Ruiz‐Santana Luis Vzquez‐Pedreo Eduardo García‐Fuentes 《Obesity (Silver Spring, Md.)》2020,28(9):1708-1717
79.
Alberto Corral‐Lpez Maksym Romensky Alexander Kotrschal Severine D. Buechel Niclas Kolm 《Journal of evolutionary biology》2020,33(2):165-177
Despite ongoing advances in sexual selection theory, the evolution of mating decisions remains enigmatic. Cognitive processes often require simultaneous processing of multiple sources of information from environmental and social cues. However, little experimental data exist on how cognitive ability affects such fitness‐associated aspects of behaviour. Using advanced tracking techniques, we studied mating behaviours of guppies artificially selected for divergence in relative brain size, with known differences in cognitive ability, when predation threat and sex ratio was varied. In females, we found a general increase in copulation behaviour in when the sex ratio was female biased, but only large‐brained females responded with greater willingness to copulate under a low predation threat. In males, we found that small‐brained individuals courted more intensively and displayed more aggressive behaviours than large‐brained individuals. However, there were no differences in female response to males with different brain size. These results provide further evidence of a role for female brain size in optimal decision‐making in a mating context. In addition, our results indicate that brain size may affect mating display skill in male guppies. We suggest that it is important to consider the association between brain size, cognitive ability and sexual behaviour when studying how morphological and behavioural traits evolve in wild populations. 相似文献
80.
Ismael Martínez Guardado Alberto Mostazo Guerra Borja Sanabria Pino Guillermo Olcina Camacho Rafael Timn Andrada 《Biology of sport / Institute of Sport》2021,38(3):367
This study compared the perceptual responses, physiological indicators and technical parameters between different training protocols focused on upper body exercises. A randomized crossover design was performed, and 12 trained individuals (age: 27.1 ± 5.7 years; height: 173.7 ± 10.7 cm; BMI: 23.9 ± 2.3) completed three resistance training sessions under different protocols separated by at least 72 h: traditional training (TT) (4 x 6 repetitions at 85% of 1RM with 120 s of rest between sets), cluster 1 (CL1) (4 x 2+2+2 repetitions at 85% of 1RM with 15 s of intra-rep rest and 80 s between sets), and cluster 2 (CL2) (24 repetitions at 85% of 1RM with 15 s of inter-set recovery). Before training, arterial blood pressure (BP) and repetitions to failure of pull-up and push-up (FT) were collected. Muscle oxygen saturation (SmO2) in the chest and movement velocity were evaluated in barbell bench press during the training session. After finishing, lactate, BP, rate of perceived exertion and FT were assessed. The percentage of velocity loss (TT: 19.24%; CL1: 5.02% and CL2: 7.30%) in the bench press and lactate concentration (TT: 8.90 mmol·l-1; CL1: 6.13 mmol·l-1 and CL2: 5.48 mmol·l-1) were significantly higher (p < 0.05) for TT compared to both CLs. RPE values were higher (p < 0.05) in TT compared to CL1 (7.95 a.u. vs. 6.91 a.u., respectively). No differences (p > 0.05) were found between protocols for SmO2, BP, FT, pain or heart rate between set configurations. Cluster configurations allow one to maintain higher movement velocity and lower lactate and RPE values compared to a traditional configuration, but with similar concentrations of SmO2. 相似文献