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101.
Maria Davern Noel E. Donlon Andrew Sheppard Fiona O’ Connell Conall Hayes Anshul Bhardwaj Emma Foley Dermot O’ Toole Niamh Lynam-Lennon Narayanasamy Ravi John V. Reynolds Stephen G. Maher Joanne Lysaght 《Translational oncology》2021,14(6):101062
Use of immune checkpoint inhibitors (ICIs) with chemotherapy to enhance responses in oesophageal adenocarcinoma (OAC) is an attractive approach. We identified subpopulations of OAC cells expressing inhibitory immune checkpoint (IC) ligands (PD-L1, PD-L2 and CD160) and receptors (PD-1, TIGIT, TIM-3, LAG-3 and A2aR) in vitro and in ex vivo biopsies. Combination chemotherapy regimens FLOT and CROSS promote a more immune-resistant phenotype through upregulation of IC ligands and receptors on OAC cells in vitro. Importantly, this study investigated if OAC cells, enriched for ICs exhibited a more stem-like and senescent-like phentoype. FLOT preferentially upregulates PD-L1 on a stem-like OAC cell phenotype, defined by ALDH activity. Expression of senescence-associated β-galactosidase is induced in a subpopulation of OAC cells following FLOT and CROSS chemotherapy treatment, along with enhanced expression of TIM-3 and A2aR ICs. Blockade of PD-1 signalling in OAC cells induced apoptosis and enhanced FLOT and CROSS chemotherapy toxicity in vitro. Upregulation of ICs on OAC cells following chemotherapy may represent potential mechanisms of chemo-immune resistance. Combination ICIs may be required to enhance the efficacy of chemotherapy and immunotherapy in OAC patients. 相似文献
102.
Michaela R. Bruton Nicholas O’Dwyer Roger Adams 《Journal of electromyography and kinesiology》2013,23(4):747-758
Potential sex differences in patterns of movement of recreational and competitive athletes were investigated in a systematic review of lower limb kinematics, muscle activation and stiffness during landing and hopping tasks. Little support for sex-specific lower limb kinematic patterns was found in 17 studies retrieved on landing and hopping. Ten studies retrieved on muscle activation during landing provided no support for sex-specific patterns. Four articles retrieved on leg stiffness established that absolute stiffness was lower in females, but differences in stiffness normalized to body mass were less clear. The wider literature indicates that a combination of biological, environmental and sociocultural constraints may shape movement patterns differently in females and males. Sociocultural factors differentially affect accumulated motor experience, practice opportunities and focus of attention in females, leading to differences in motor skill that confound the comparison of female and male movements. The findings of the review support the hypothesis that such sex differences in athletic performance are likely to diminish or disappear with increasing skill. In everyday movement tasks, however, where level of skill is a less meaningful dimension than in sport, differences in movement patterns observed between females and males point instead to the influence of subtle societal expectations on movement patterns. 相似文献
103.
I. N. Bolotov A. A. Makhrov Yu. V. Bespalaya I. V. Vikhrev O. V. Aksenova P. E. Aspholm M. Yu. Gofarov A. N. Ostrovskii I. Yu. Popov I. S. Pal’tser M. Rudzite M. Rudzitis I. S. Voroshilova S. E. Sokolova 《Biology Bulletin》2013,40(2):221-231
This paper continues a discussion on the number of pearl mussel species of the genus Margaritifera in northern Europe. A biometric study of 1711 pearl mussel Margaritifera margaritifera shells from 15 rivers in Russia and Latvia (basins of the White and Baltic seas) has been conducted. All the examined samples fall into two groups: the northern group (with the shells more flattened on average, f. margaritifera) and the southern one (with more convex shells, f. elongata); the boundary between these groups is at 63° N. Analysis of intrapopulation variation has shown that the samples contain individuals that correspond to f. margaritifera, f. elongata, and f. borealis. However, any hiatus between these forms is absent in all the samples, and individuals belonging to two intermediate forms are rather frequent. The hypothesis on the species specificity of the shell valve frontal section has not been confirmed based on examination of large shell samples. The pearl mussels inhabiting rivers of Northern Europe belong to a single species, M. margaritifera. 相似文献
104.
N. F. Myasoedov L. A. Andreeva L. A. Lyapina T. A. Shubina M. E. Grigor’eva T. Yu. Obergan 《Biology Bulletin》2013,40(3):304-306
It has been established that fivefold intranasal administration of the peptide Leu-Pro-Gly-Pro (1 mg/kg) to rats with developing refractory hyperglycemia leads to restoration and normalization of the functions of anticoagulation and insular systems. In the blood of experimental animals, there was a decrease in the sugar level and platelet aggregation and an increase in anticoagulant and all kinds of fibrinolytic (total, enzymatic, non-enzymatic, Hageman-dependent) activity. 相似文献
105.
L. A. Gerlinskaya E. L. Zav’yalov A. I. Chechulin M. P. Moshkin 《Biology Bulletin》2013,40(7):606-613
Cestodes found in water voles (Arvicola terrestris L., 1758) trapped over six breeding seasons in the same local habitats included the following species: Arvicolepis transfuga (Spassky et Merkuscheva 1967), Paranoplacepala blanchardi (Moniez 1891), P. omphalodes (Hermann 1783), Parandria feodorovi (Gulyaev et Chetchulin 1996), Aprostatandrya dentate (Galli-Valerio 1905), and Arostrilepis microtis (Gulyaev et Chetchulin 2005). The dependence of cestode maturation on interannual variation in the food supply, territorial status, and morphofunctional characters of the hosts was analyzed in the two most abundant species, A. transfuga and P. feodorovi. The results showed that differences in host sex and food supply had no significant effect on cestode maturation. Judging from the proportion of gravid helminths of either species, the rate of their maturation was higher in nonresident than in resident voles. This proportion negatively correlated with body weight of male or female voles. It also negatively correlated with male fecal testosterone level, whereas correlations with fecal protein and progesterone levels were positive. The observed relationships do not explain why the occurrence frequency of gravid cestodes was higher in nonresident water voles, because they either did not differ from residents in parameters relevant to cestode maturation (body weight, fecal protein and testosterone levels) or the difference was opposite in direction (fecal progesterone was higher in resident voles). Nevertheless, an increase in the proportion of gravid cestodes in nonresident water voles may provide for more effective dispersal of these parasites. 相似文献
106.
O. V. Shelepova V. V. Kondrat’eva T. V. Voronkova L. S. Olekhnovich 《Biology Bulletin》2013,40(3):275-280
Dynamic changes in the content of acetylsalicylic acid and the output and qualitative composition of essential oil have been studied in mint plants (Mentha spicata L. and cultivar Medichka) during their ontogenesis with allowance for changes in weather conditions. Ontogenetic changes in the level of acetylsalicylic acid in leaf tissues are found to be similar in both cv. Medichka and M. spicata. In the case of cv. Medichka, this change is connected with the dynamics of the production and the qualitative composition of essential oil; in the case of M. spicata, this connection is less expressed. The role of acetylsalicylic acid and essential oil in plant adaptation to the environment is discussed. 相似文献
107.
D. V. Shibalev V. A. Vasil’ev O. E. Lazebnyi E. M. Suchodolskaya A. M. Kulikov D. A. Dronova M. L. Butovskaya A. P. Ryskov 《Russian Journal of Genetics》2013,49(12):1258-1260
The molecular genetic analysis of the polymorphic variants of the CAG repeat-containing locus of the androgen receptor (AR) gene was performed in the populations of Hadza and Datoga. Allele frequency distribution patterns were established. Alleles containing 20–25 repeats were the most abundant in both populations. The populations studied were compared with Asians (Han), white Americans, and Africans (Ariaal). Statistically significant difference between populations of Hadza and Datoga in the distribution of the AR allelic variants was demonstrated. 相似文献
108.
N. V. Obroucheva I. A. Sin’kevich S. V. Lityagina G. V. Novikova 《Russian Journal of Plant Physiology》2013,60(3):437-441
The validity of the acid-growth hypothesis is proved for the case of cell elongation initiation in germinating seeds of horse chestnut (Aesculus hippocastanum L.), the embryo axes of which are known to extend during the first stages of germination only by cell elongation. During seed imbibition, H+-ion excretion was firstly low; it increased several times prior to radicle emergence and was maintained at a high level during growth initiation and further cell elongation. Cell wall acidification and radicle emergence were enhanced in the presence of 0.02 mM fusicoccin, thus indicating the involvement of the plasma membrane H+-ATPase in the execution of acid growth. The presence of this enzyme and its activator (14-3-3 protein) in microsomal fractions obtained from radicles and hypocotyls of the embryo axes during and after initiation of cell elongation was demonstrated immunochemically. It is supposed that the initiation of cell elongation at early germination occurs via the activation of the plasma membrane H+-ATPase and results in the acidification of cell walls, leading to their higher extensibility, in accordance with the hypothesis of acid growth. 相似文献
109.
110.
Umberto Nicosia Fabio Massimo Petti Gianluca Perugini Simone D’Orazi Porchetti Eva Sacchi Maria Alessandra Conti 《Ichnos》2013,20(1-2):69-90
A really unexpected finding of sauropod and theropod footprints in southern Latium raises to four the number of the trampled levels recognized in central and southern Italy. After the recent findings in Latest Jurassic and Early, mid and Late Cretaceous carbonate platform deposits of the Periadriatic region, dinosaur footprints seem to provide very important paleogeographic constraints for reconstructing the geodynamic history of the Mediterranean area. The presence of a varied ichnoassociation makes acceptance of the current paleogeographic models concerning the relative and absolute position of the Laziale-Abruzzese-Campano and of Apulian-Dinaric domains during the Late Cretaceous more and more problematic. Dinosaur footprints, combined with other paleontological data, demonstrate that these areas were never completely pulled apart by deep seaways, while frequent or continuous links between them, and to southern and northern mainlands, probably persisted. These data also allowed us to improve our understanding of the timing of the Mesozoic plate motion in this segment of the Western Tethys. 相似文献