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991.
Stella Miranda Malcher Julio Cesar Pieczarka Adenilson Leo Pereira Paulo Jos Siqueira do Amaral Rogrio Vieira Rossi Juliane Saldanha Cleusa Yoshiko Nagamachi 《Ecology and evolution》2021,11(12):7125
Mesomys Wagner, 1845 (Rodentia, Echimyidae, Eumysopinae) currently has four recognized species, three of which occur in Brazil: Mesomys hispidus (probably a species complex), M. occultus, and M. stimulax. Mesomys leniceps is found in montane forests of northern Peru. Mesomys stimulax, the focus of the present study, has a distribution that is restricted to the central and eastern Amazonia south of the Amazon River, extending from the left bank of the Tapajós River to the right bank of the Tocantins River, and south to the southeast portion of Pará State. The genus presents karyotypes with diploid number 2n = 60 and Fundamental Number (FN) = 116 for M. hispidus and M. stimulax, and 2n = 42, FN = 54 for M. occultus. We studied the karyotype of a female specimen of M. stimulax collected from the Tapirapé‐Aquiri National Forest, Marabá, Pará, Brazil, in the Xingu/Tocantins interfluvium. The obtained karyotype (2n = 60 and FN = 110) differs from that described in the literature for both M. stimulax and M. hispidus by exhibiting more biarmed chromosomes, probably due to pericentric inversions and/or centromeric repositioning, and exhibiting differences in the amount and distribution of constitutive heterochromatin (CH). These results suggest that, similar to what has already been proposed for M. hispidus, M. stimulax may represent a species complex and/or cryptic species. The mechanisms of chromosomal diversification in Mesomys and the biogeographic implications are discussed reinforcing the need for broad systematic review for Mesomys. 相似文献
992.
de Freitas Cleverson Henrique Elli Elvis Felipe Sentelhas Paulo Cesar 《International journal of biometeorology》2021,65(10):1659-1673
International Journal of Biometeorology - The concept of yield gaps provides a basis for identifying the main sources of production losses, caused by water or management deficiencies, which may... 相似文献
993.
Ulises Ahumada-Castro Andrea Puebla-Huerta Victor Cuevas-Espinoza Alenka Lovy J. Cesar Cardenas 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2021,1868(11):119099
Cellular senescence generates a permanent cell cycle arrest, characterized by apoptosis resistance and a pro-inflammatory senescence-associated secretory phenotype (SASP). Physiologically, senescent cells promote tissue remodeling during development and after injury. However, when accumulated over a certain threshold as happens during aging or after cellular stress, senescent cells contribute to the functional decline of tissues, participating in the generation of several diseases. Cellular senescence is accompanied by increased mitochondrial metabolism. How mitochondrial function is regulated and what role it plays in senescent cell homeostasis is poorly understood. Mitochondria are functionally and physically coupled to the endoplasmic reticulum (ER), the major calcium (Ca2+) storage organelle in mammalian cells, through special domains known as mitochondria-ER contacts (MERCs). In this domain, the release of Ca2+ from the ER is mainly regulated by inositol 1,4,5-trisphosphate receptors (IP3Rs), a family of three Ca2+ release channels activated by a ligand (IP3). IP3R-mediated Ca2+ release is transferred to mitochondria through the mitochondrial Ca2+ uniporter (MCU), where it modulates the activity of several enzymes and transporters impacting its bioenergetic and biosynthetic function. Here, we review the possible connection between ER to mitochondria Ca2+ transfer and senescence.Understanding the pathways that contribute to senescence is essential to reveal new therapeutic targets that allow either delaying senescent cell accumulation or reduce senescent cell burden to alleviate multiple diseases. 相似文献
994.
Victor G.D. Orrico Taran Grant Julian Faivovich Mauricio Rivera‐Correa Marco A. Rada Mariana L. Lyra Carla S. Cassini Paula H. Valdujo Walter E. Schargel Denis J. Machado Ward C. Wheeler Cesar Barrio‐Amors Daniel Loebmann Jií Moravec Juliana Zina Mirco Sol Marcelo J. Sturaro Pedro L.V. Peloso Pablo Suarez Clio F.B. Haddad 《Cladistics : the international journal of the Willi Hennig Society》2021,37(1):73-105
The relationships of the hyline tribe Dendropsophini remain poorly studied, with most published analyses dealing with few of the species groups of Dendropsophus. In order to test the monophyly of Dendropsophini, its genera, and the species groups currently recognized in Dendropsophus, we performed a total evidence phylogenetic analysis. The molecular dataset included sequences of three mitochondrial and five nuclear genes from 210 terminals, including 12 outgroup species, the two species of Xenohyla, and 93 of the 108 recognized species of Dendropsophus. The phenomic dataset includes 46 terminals, one per species (34 Dendropsophus, one Xenohyla, and 11 outgroup species). Our results corroborate the monophyly of Dendropsophini and the reciprocal monophyly of Dendropsophus and Xenohyla. Some species groups of Dendropsophus are paraphyletic (the D. microcephalus, D. minimus, and D. parviceps groups, and the D. rubicundulus clade). On the basis of our results, we recognize nine species groups; for three of them (D. leucophyllatus, D. microcephalus, and D. parviceps groups) we recognize some nominal clades to highlight specific morphology or relationships and facilitate species taxonomy. We further discuss the evolution of oviposition site selection, where our results show multiple instances of independent evolution of terrestrial egg clutches during the evolutionary history of Dendropsophus. 相似文献
995.
996.
997.
de Lucena Marcos B. Cordeiro Cesar A. M. M. Valentin Jean L. Aguiar Aline A. 《Environmental Biology of Fishes》2022,105(5):561-573
Environmental Biology of Fishes - Invertivorous fish species such as Halichoeres radiatus feed on benthic active prey and need to spend most of their time foraging. Even though the Labridae family... 相似文献
998.
999.
The response of one susceptible and three resistant Brachiaria spp. (Hemiptera: Cercopidae) genotypes to individual or combined attacks by nymphs of Aeneolamia varia (F.), Aeneolamia reducta (Lallemand), Zulia carbonaria (Lallemand), and Zulia pubescens (F.) was studied. We assessed the effect of infesting plants of the susceptible check BRX 44-02 and of the A. varia-resistant genotypes CIAT 6294 and CIAT 36062 with A. varia, Z. carbonaria, or Z. pubescens either alone or in two-species combinations. In a second trial, we studied the performance of BRX 44-02, CIAT 6294, and the multiple resistant clone SX01NO/0102 exposed to individual or combined attack by A. reducta and Z. carbonaria. In a third trial, we compared the response of BRX 44-02, CIAT 6294, and CIAT 36062 to individual A. varia, Z. carbonaria, or Z. pubescens attack as opposed to a combined three-species attack. Plant damage scores and percentage of nymphal survival were recorded in all three trials. Data on percentage of survival indicated that competition between and among spittlebug species occurs. However, we found no evidence of interaction between species competition and different levels of resistance to spittlebug. Rather, host genotype reactions conformed to previously known categories of resistance regardless of the presence of more than one spittlebug species. Resistance rather than competition seems to have been the overriding factor determining nymph survival and resistance expression (damage scores) in these experiments. Our results corroborate the need to develop brachiariagrass genotypes with multiple resistance to spittlebugs. 相似文献
1000.
The symbiosis between legumes and rhizobia is characterised by the formation of dinitrogen-fixing root nodules. In natural
conditions, nitrogen fixation is strongly impaired by abiotic stresses which generate over-production of reactive oxygen species.
Since one of the nodule main antioxidant systems is the ascorbate–glutathione cycle, NADPH recycling that is involved in glutathione
reduction is of great relevance under stress conditions. NADPH is mainly produced by glucose 6-phosphate dehydrogenase (G6PDH;
EC 1.1.1.49) and 6-phosphogluconate dehydrogenase (6PGDH; EC 1.1.1.44) from the oxidative pentose phosphate pathway, and also
by NADP+-dependent isocitrate dehydrogenase (ICDH; EC 1.1.1.42). In this work, 10 μM paraquat (PQ) was applied to pea roots in order
to determine the in vivo relationship between oxidative stress and the activity of the NADPH-generating enzymes in nodules.
Whereas G6PDH and 6PGDH activities remained unchanged, a remarkable induction of ICDH gene expression and a dramatic increase
of the ICDH activity was observed during the PQ treatment. These results support that ICDH has a key role in NADPH recycling
under oxidative stress conditions in pea root nodules. 相似文献