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741.
Yi Yu Diogo Ladeiras Yuyan Xiong Kayluz Frias Boligan Xiujie Liang Stephan von Gunten Robert E. Hunger Xiu-Fen Ming Zhihong Yang 《Journal of cellular physiology》2020,235(12):9997-10011
Elevated arginase type II (Arg-II) associates with higher grade tumors. Its function and underlying molecular mechanisms in melanoma remain elusive. In the present study, we observed a significantly higher frequency of Arg-II expression in melanoma of patients with metastasis than those without metastasis. Silencing Arg-II in two human melanoma cell lines slowed down the cell growth, while overexpression of native but not a catalytically inactive Arg-II promoted cell proliferation without affecting cell death. Treatment of cells with arginase inhibitor also reduced melanoma cell number, demonstrating that Arg-II promotes melanoma cell proliferation dependently of its enzymatic activity. However, results from silencing Arg-II or overexpressing native or the inactive Arg-II as well as treatment with arginase inhibitor showed that Arg-II promotes melanoma metastasis-related processes, such as melanoma cell migration and adhesion on endothelial cells, independently of its enzymatic activity. Moreover, the treatment of the cells with STAT3 inhibitor suppressed Arg-II-promoted melanoma cell migration and adhesion. Furthermore, catalase, but not superoxide dismutase, prevented STAT3 activation as well as increased melanoma cell migration and adhesion induced by overexpressing native or the inactive Arg-II. Taken together, our study uncovers both activity-dependent and independent mechanisms of Arg-II in promoting melanoma progression. While Arg-II enhances melanoma cell proliferation through polyamine dependently of its enzymatic activity, it promotes metastasis-related processes, that is, migration and adhesion onto endothelial cell, through mitochondrial H2O2-STAT3 pathway independently of the enzymatic activity. Suppressing Arg-II expression rather than inhibiting its enzymatic activity may, therefore, represent a novel strategy for the treatment of melanoma. 相似文献
742.
Rui Diogo Marta Linde‐Medina Virginia Abdala Miriam A. Ashley‐Ross 《Biological reviews of the Cambridge Philosophical Society》2013,88(1):196-214
Most textbooks and research reports state that the structures of the tetrapod forelimbs and hindlimbs are serial homologues. From this view, the main challenge of evolutionary biologists is not to explain the similarity between tetrapod limbs, but instead to explain why and how they have diverged. However, these statements seem to be related to a confusion between the serial homology of the vertebrate pelvic and pectoral appendages as a whole, and the serial homology of the specific soft‐ and hard‐tissue structures of the tetrapod forelimbs and hindlimbs, leading to an even more crucial and puzzling question being overlooked: why are the skeletal and particularly the muscle structures of the forelimb and hindlimb actually so strikingly similar to each other? Herein we provide an updated discussion of these questions and test two main hypotheses: (i) that the similarity of the limb muscles is due to serial homology; and (ii) that tetrapods that use hindlimbs for a largely exclusive function (e.g. bipedalism in humans) exhibit fewer cases of similarity between forelimbs and hindlimbs than do quadrupedal species. Our review shows that of the 23 arm, forearm and hand muscles/muscle groups of salamanders, 18 (78%) have clear ‘topological equivalents' in the hindlimb; in lizards, 14/24 (58%); in rats, 14/35 (40%); and in modern humans, 19/37 (51%). These numbers seem to support the idea that there is a plesiomorphic similarity and subsequent evolutionary divergence, but this tendency actually only applies to the three former quadrupedal taxa. Moreover, if one takes into account the total number of ‘correspondences’, one comes to a surprising and puzzling conclusion: in modern humans the number of forelimb muscles/muscle groups with clear ‘equivalents’ in the hindlimb (19) is substantially higher than in quadrupedal mammals such as rats (14), lizards (14) and even salamanders (18). These data contradict the hypothesis that divergent functions lead to divergent morphological structures. Furthermore, as we show that at least five of the 19 modern human adult forelimb elements that have a clear hindlimb ‘equivalent’ derive from embryonic anlages that are very different from the ones giving rise to their adult hindlimb ‘equivalents’, they also contradict the hypothesis that the similarity in muscle structures between the forelimb and hindlimb of tetrapods such as modern humans are due to their origin as serial homologues. This similarity is instead the result of phylogenetically independent evolutionary changes leading to a parallelism/convergence due to: (i) developmental constraints, i.e. similar molecular mechanisms are involved (particularly in the formation of the neomorphic hand), but this does not necessarily mean that similar anlages are used to form the similar adult structures; (ii) functional constraints, related to similar adaptations; (iii) topological constraints, i.e. limited physical possibilities; and even (iv) phylogenetic constraints, which tend to prevent/decrease the occurrence of new homoplasic similarities, but also help to keep older, ancestral homoplasic resemblances. 相似文献
743.
744.
Rui Diogo Adeyemi Adesomo Kimberly S. Farmer Rachel J. Kim Fatimah Jackson 《Evolutionary anthropology》2023,32(2):67-82
In the past decades, it has been increasingly recognized that some areas of science, such as anthropology, have been plagued by racist, Western-centric, and/or sexist biases. Unfortunately, an acculturation process to racism and sexism has been occurring for generations leading to systemic inequities that will take a long time to disappear. Here, we highlight the existence of current examples of racism, Western-centrism and sexism within: (1) the most popular anatomical atlases used in biological, anthropological and medical education; (2) prominent natural history museums and World Heritage Sites; (3) biological and anthropological scientific research publications; and (4) popular culture and influential children's books and educational materials concerning human biology and evolution. 相似文献
745.
Josep Maria Potau Rosa Artells Gaëlle Bello Carmen Muñoz Mariano Monzó Juan Francisco Pastor Félix de Paz Mercedes Barbosa Rui Diogo Bernard Wood 《International journal of primatology》2011,32(4):931-944
The supraspinatus muscle is a key component of the soft tissues of the shoulder. In pronograde primates, its main function,
in combination with the other rotator cuff muscles (subscapularis, infraspinatus, and teres minor), is to stabilize the glenohumeral
joint, whereas in orthograde primates it functions together with the deltoid, to elevate the upper extremity in the scapular
plane. To determine whether these functional differences are also reflected in the molecular biochemistry of the supraspinatus
muscles involved in these different locomotor modes, we used real-time polymerase chain reaction (RT-PCR) to analyze the expression
of the myosin heavy chain (MHC) isoforms in supraspinatus muscles from modern humans and 12 species of pronograde and orthograde
primates. The MHC expression pattern in the supraspinatus muscle of pronograde primates was consistent with its function as
a tonic and postural muscle, whereas the MHC expression pattern observed in the supraspinatus muscle of nonhuman orthograde
primates was that of a muscle that emphasizes speed, strength, and less resistance to fatigue. These findings are consistent
with the role of the supraspinatus in the posture and locomotor modes of these groups of nonhuman primates. The humans included
in the study had an expression pattern similar to that of the nonhuman orthograde primates. In conclusion, molecular analysis
of skeletal muscles via RT-PCR can contribute to a better understanding of the morphological and functional characteristics
of the primate musculoskeletal system. 相似文献
746.
John T. Melchior Ryan G. Walker Jamie Morris Martin K. Jones Jere P. Segrest Diogo B. Lima Paulo C. Carvalho Fábio C. Gozzo Mark Castleberry Thomas B. Thompson W. Sean Davidson 《The Journal of biological chemistry》2016,291(10):5439-5451
Apolipoprotein (apo) A-I mediates many of the anti-atherogenic functions attributed to high density lipoprotein. Unfortunately, efforts toward a high resolution structure of full-length apoA-I have not been fruitful, although there have been successes with deletion mutants. Recently, a C-terminal truncation (apoA-IΔ185–243) was crystallized as a dimer. The structure showed two helical bundles connected by a long, curved pair of swapped helical domains. To compare this structure to that existing under solution conditions, we applied small angle x-ray scattering and isotope-assisted chemical cross-linking to apoA-IΔ185–243 in its dimeric and monomeric forms. For the dimer, we found evidence for the shared domains and aspects of the N-terminal bundles, but not the molecular curvature seen in the crystal. We also found that the N-terminal bundles equilibrate between open and closed states. Interestingly, this movement is one of the transitions proposed during lipid binding. The monomer was consistent with a model in which the long shared helix doubles back onto the helical bundle. Combined with the crystal structure, these data offer an important starting point to understand the molecular details of high density lipoprotein biogenesis. 相似文献
747.
Amanda Arcanjo Diogo Cavalcanti Cabral-de-Mello Cesar Martins Rita de Cássia de Moura Maria José de Souza 《Genetics and molecular biology》2013,36(3):341-346
The genus Phanaeus is included in the tribe Phanaeini, one of the most diverse tribes within the subfamily Scarabaeinae in terms of chromosomal characteristics. However, so far the species of this genus were not studied with differential cytogenetic techniques, limiting any inference of the probable mechanisms responsible for this diversity. In this work, several techniques were applied with the aim of cytogenetically characterizing two Phanaeus species. The karyotype found for Phanaeus (Notiophanaeus) chalcomelas was 2n = 12, neo-XY, and that of P. (N.) splendidulus was 2n = 20, Xyp, considered primitive for the family Scarabaeidae. The chromosomes of both species showed a high amount of constitutive heterochromatin (CH), with blocks rich in base pairs GC (CMA3+). Moreover, in P. (N.) chalcomelas the marks revealed by C-banding and fluorochrome staining were different in size, showing CH variability. Sites of 18S ribosomal DNA (rDNA) were identified in one autosomal pair of P. (N.) chalcomelas and in five autosomal pairs of P. (N.) splendidulus. On the other hand, only one autosomal pair exhibited 5S rDNA sequences in these species. The results suggest that the karyotype differentiation of the Phanaeus species studied here involved pericentric inversions and centric fusions, as well as mechanisms related to amplification and dispersion of CH and rDNA sequences. 相似文献
748.
749.
750.
A genealogical view of geographical variation 总被引:4,自引:0,他引:4