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31.
A new long-snouted whipray, Himantura lobistoma, is described on the basis of seven specimens collected from the southeastern sector of the South China Sea, off western
Borneo. It belongs to a subgroup of Himantura species provisionally defined herein as the “uarnacoides” complex that includes five nominal species: H. chaophraya, H. granulata, H. hortlei, H. pastinacoides, and H. uarnacoides. These whiprays all have a similar lateral disc shape (i.e., pectoral-fin apices broadly rounded rather than narrowly rounded
or angular), a plain colouration (i.e., usually uniform light to dark brown dorsally, and pale or whitish ventrally with or
without a dark margin), a long and slender whiplike tail, and platelike denticles in a broad dorsal band in adults. Himantura lobistoma can be distinguished from the superficially similar H. hortlei by its highly protrusible mouth and pelvic girdle with prominent lateral prepelvic processes. It differs from other members
of the “uarnacoides” complex by a combination of internal and external morphological characteristics (e.g., having an extremely
elongate snout and very small eyes). Another long-snouted stingray from the region, Dasyatis microphthalmus Chen, inadequately described and known only from the lost holotype, is considered a nomen dubium. It had been assigned to
Himantura based on the absence of an obvious ventral cutaneous tailfold but may be conspecific with D. acutirostra. 相似文献
32.
Weiyang He Qiong Wang Jennings Xu Xiuling Xu Mabel T. Padilla Guosheng Ren Xin Gou Yong Lin 《Autophagy》2012,8(12):1811-1821
Although it is known that tumor necrosis factor-related apoptosis-inducing ligand (TNFSF10/TRAIL) induces autophagy, the mechanism by which autophagy is activated by TNFSF10 is still elusive. In this report, we show evidence that TRAF2- and RIPK1-mediated MAPK8/JNK activation is required for TNFSF10-induced cytoprotective autophagy. TNFSF10 activated autophagy rapidly in cancer cell lines derived from lung, bladder and prostate tumors. Blocking autophagy with either pharmacological inhibitors or siRNAs targeting the key autophagy factors BECN1/Beclin 1 or ATG7 effectively increased TNFSF10-induced apoptotic cytotoxicity, substantiating a cytoprotective role for TNFSF10-induced autophagy. Blocking MAPK8 but not NFκB effectively blocked autophagy, suggesting that MAPK8 is the main pathway for TNFSF10-induced autophagy. In addition, blocking MAPK8 effectively inhibited degradation of BCL2L1/Bcl-xL and reduction of the autophagy-suppressing BCL2L1–BECN1complex. Knockdown of TRAF2 or RIPK1 effectively suppressed TNFSF10-induced MAPK8 activation and autophagy. Furthermore, suppressing autophagy inhibited expression of antiapoptosis factors BIRC2/cIAP1, BIRC3/cIAP2, XIAP and CFLAR/c-FLIP and increased the formation of TNFSF10-induced death-inducing signaling complex (DISC). These results reveal a critical role for the MAPK8 activation pathway through TRAF2 and RIPK1 for TNFSF10-induced autophagy that blunts apoptosis in cancer cells. Thus, suppression of MAPK8-mediated autophagy could be utilized for sensitizing cancer cells to therapy with TNFSF10. 相似文献
33.
1H, 13C, and 15N backbone and side-chain chemical shift assignments for the 29 kDa human galectin-1 protein dimer 总被引:1,自引:0,他引:1
Irina V. Nesmelova Mabel Pang Linda G. Baum Kevin H. Mayo 《Biomolecular NMR assignments》2008,2(2):203-205
Galectin-1 is an important regulator of leukocyte function and tumor angiogenesis. Recently, this lectin has been identified
as a molecular target for the potent angiogenesis inhibitor anginex. Here, we report 1H, 13C, and 15N chemical shift assignments for human galectin-1 as determined by using heteronuclear triple resonance NMR spectroscopy. 相似文献
34.
Exceptional chromosomal variability makesCtenomys an excellent model for evolutionary cytogenetic analysis. Six species belonging to three evolutionary lineages were studied
by means of restriction endonuclease and C-chromosome banding. The resulting banding patterns were used for comparative analysis
of heterochromatin distribution on chromosomes. This combined analysis allowed intra- and inter-specific heterochromatin variability
to be detected, groups of species belonging to different lineages to be characterized, and phylogenetic relationships hypothesized
from other data to be supported. The “ancestral group”,Ctenomys pundti andC. talarum, share three types of heterochromatin, the most abundant of which was also found in C. aff.C. opimus, suggesting that the latter species also belongs to the “ancestral group”. Additionally, within the subspeciesC. t. talarum, putative chromosomal rearrangements distinguishing two of the three chromosomal races were identified. Two species belong
to an “eastern lineage”,C. osvaldoreigi andC. rosendopascuali, and share only one type of heterochromatin homogeneously distributed across their karyotypes.C. latro, the only analyzed species from the “chacoan” lineage, showed three types of heterochromatin, one of them being that which
characterizes the “eastern lineage”.C. aff.C. opimus, because of its low heterochromatin content, is the most primitive karyotype of the genus yet described. The heterochromatin
variability showed by these species, reflecting the evolutionary divergence toward different heterochromatin types, may have
diverged since the origin of the genus. Heterochromatin amplification is proposed as a trend withinCtenomys, occurring independently of chromosomal change in diploid numbers. 相似文献
35.
Villar Carlos Stripeikis Jorge Colautti Dario D'Huicque Liliana Tudino Mabel Bonetto Carlos 《Hydrobiologia》2001,457(1-3):225-233
Cd, Cr, Cu and Pb concentrations were measured in the water and these plus Zn were measured in the diet, muscle and liver of the detritivorous fish Prochilodus lineatus and the omnivorous fish Pterodoras granulosus at two sites (Lower Paraná River and Río de la Plata right margin) located upstream and downstream, respectively, from Buenos Aires, an important source of xenobiotics. Cu and Cr concentrations in water were higher in the Río de la Plata coastal waters, while Cd and Pb were below detection limits. The stomach contents of P. lineatus showed a higher metal content at the estuary, attaining concentrations within the range reported for contaminated sediments. However, metals in fish tissue were not higher at the estuary and, except for Cd in liver, were lower than in the organic fraction of the stomach content. Thus, only Cd was accumulated. The P. granulosus diet was composed mainly of river vegetation debris and clams, Corbicula fluminea, at the estuary. Cd, Cu and Pb in liver were higher at the estuary while only Cu was higher in the diet at this site. The different nature of the diet seems associated with a differential bioavailability of its metal content. P. granulosus accumulates Cu at both sites and Cd at the estuary. Both fishes showed higher metal content in liver than in muscle. Cr in liver was below detection limits. No relation was found between metal content and fish size. Overall, metal content in fish tissues were low, except for Cu in P. granulosus and Cd in P. lineatus, similar to those of uncontaminated sites, suggesting that homeostatic mechanisms prevent metal accumulation. 相似文献
36.
María José Arauz Valéry Ridde Libia Milena Hernández Yaneth Charris Mabel Carabali Luis ángel Villar 《PloS one》2015,10(2)
BackgroundDengue fever is a public health problem in the tropical and sub-tropical world. Dengue cases have grown dramatically in recent years as well as dengue mortality. Colombia has experienced periodic dengue outbreaks with numerous dengue related-deaths, where the Santander department has been particularly affected. Although social determinants of health (SDH) shape health outcomes, including mortality, it is not yet understood how these affect dengue mortality. The aim of this pilot study was to develop and pre-test a social autopsy (SA) tool for dengue mortality.ConclusionsThe SA tool is based on the scientific literature, a validated conceptual framework, researchers’ and health professionals’ expertise, and a pilot study. It is the first time that a SA tool has been created for the dengue mortality context. Our work furthers the study on SDH and how these are applied to neglected tropical diseases, like dengue. This tool could be integrated in surveillance systems to provide complementary information on the modifiable and avoidable death-related factors and therefore, be able to formulate interventions for dengue mortality reduction. 相似文献
37.
38.
Luisa F. Escobar-Alvarado Mabel Vaca-Mier Raymundo López-Callejas 《International journal of phytoremediation》2018,20(2):184-189
Industrial pollutants such as heavy metals and hydrocarbons in soils represent a serious concern due to their persistence and negative effects on the environment, affecting cellular processes in living organisms and even causing mutations and cancer. The main objectives of this work were to evaluate the efficiency of Opuntia ficus in the phytoremediation of a soil polluted with used motor oil. Two other species, one with different and one with similar characteristics, relatively, were used for comparison purposes: Lolium perenne and Aloe barbadensis. The effect of the plants on lead solubility and bioaccumulation, the biomass production of each specie and the microbial counts and bacterial identification for each experiment was studied. Total petroleum hydrocarbons (TPH) were measured every 5 weeks throughout the 20-week phytoremediation experiment. At the end of the experiment soluble Pb, Pb extracted by the plant species, microbiological counts, total biomass and bacterial species in soil were analyzed. Even though Lolium perenne showed the highest TPH removal (47%), Opuntia ficus produced the highest biomass and similar removal (46%). Since Opuntia ficus requires low amounts of water and grows fast, it would be a suitable option in the remediation of soils polluted with hydrocarbons and/or heavy metals. 相似文献
39.
Mabel A. Rice 《The Botanical review》1945,11(5):288-298
40.
Michael S. Engel Diying Huang Abdulaziz S. Alqarni Chenyang Cai Mabel Alvarado Laura C.V. Breitkreuz Dany Azar 《Comptes Rendus Palevol》2017,16(1):5-11
A remarkably specialized parasitoid wasp of the family Scelionidae (Platygastroidea) is described and figured from mid-Cretaceous (Cenomanian) amber of the Hukawng Valley in northern Myanmar. Geoscelio mckellari Engel and Huang, gen. et sp. nov., is unique for its combination of a compact body, 12 antennal flagellomeres, a 1-2-2 tibial spur formula, a distinct malar sulcus, deeply impressed notauli, complete reduction of the wings, and basal crenulae on the metasomal terga and sterna, among many other features, and is placed within a separate tribe, Geoscelionini Engel and Huang, trib. nov. This is the first flightless species of Platygastroidea known from the Mesozoic, and its affinities with other Mesozoic and extant lineages are discussed. 相似文献