Reforma trabalhista e relações de trabalho no Brasil: por quem os sinos dobram? / Labor reform and labor relations in Brazil: for whom do the bells toll?

As reformas trabalhistas de 2017 são a mais abrangente alteração sofrida pela CLT desde seu lançamento. Este artigo compara as novas leis e o posicionamento sobre o tema por parte da CNI e do DIEESE, entidades que representam dois dos grupos sociais mais afetados: patrões industriais e trabalhadores. A partir do referencial da economia neoclássica e dos estudos de Dunlop sobre Sistemas de Relações Industriais, demonstra-se que a reforma atende diretamente aos interesses patronais, em detrimento dos pontos de vista colocados pela entidade dos trabalhadores, refletindo uma correlação de forças muito desfavorável a estes últimos, e lançando dúvidas sobre a capacidade explicativa dos sistemas "equilibrados" de Dunlop. O método consiste em apresentar as alterações na legislação, contrastando-as com o posicionamento das entidades. Verifica-se 100% de convergência entre as novas leis e a visão da CNI, com ampla rejeição por parte do DIEESE, o que indica a lógica por trás das reformas: a recomendação (neoclássica) de flexibilização do mercado de trabalho, argumento caro ao patronato, mas problematizado por vários estudos acadêmicos na área das relações de trabalho.

2017 labor reforms are the most far-reaching change Brazilian Labor Laws (CLT) has undergone since its launch. This article compares the new laws and the position on the subject by the CNI and DIEESE, entities which represent two of the most affected social groups: industrial bosses and workers. Based on the framework of neoclassical economics and Dunlop's studies on Industrial Relations Systems, it is demonstrated that the reform directly serves the employers' interests, to the detriment of points of view put forward by the workers' entity, reflecting a very unfavourable correlation of forces to the latter, and casting doubt on the explanatory power of Dunlop's "balanced" systems. The method consists of presenting changes in the legislation, contrasting them with the entities' positions. There is 100% convergence between the new laws and CNI's view on the matter, with broad rejection by DIEESE, which indicates the logic behind the reforms: the (neoclassical) recommendation for flexibility in the labor market, an argument that is dear to the bosses, but problematized by several academic studies in work relations field.

Molecular cytogenetics insights in two pelagic big-game fishes in the Atlantic, the tarpon, Megalops atlanticus (Elopiformes: Megalopidae), and the sailfish, Istiophorus platypterus (Istiophoriformes: Istiophoridae)

Some pelagic and usually large sized fishes are preferential targets for sport and commercial fishing. Despite their economic importance, cytogenetic data on their evolutionary processes and management are very deficient, especially due to logistical difficulties. Here, information for two of such charismatic species, the tarpon, Megalops atlanticus (Elopiformes: Megalopidae), and the sailfish, Istiophorus platypterus (Istiophoriformes: Istiophoridae), both with a wide Atlantic distribution, were provided. Cytogenetic data were obtained using conventional methods (Giemsa staining, Ag-NORs technique, and C-banding), base-specific fluorochrome staining and fluorescence in situ hybridization (FISH) with rDNA probes. Megalops atlanticus has 2n = 50 chromosomes, all acrocentric ones (NF = 50), while Istiophorus platypterus has 2n = 48 chromosomes, 2m + 2st + 44a (NF = 52). Megalops atlanticus populations from the South Atlantic and Caribbean share identical karyotypic patterns, likely associated with gene flow between them. In turn, I. platypterus presents karyotype similarities with phylogenetically close groups, such as Carangidae. The chromosomal characteristics of these species highlight their independent evolutionary paths. Additionally, the current data contribute to knowledge of new aspects of pelagic fish fauna and will support further comparative studies with congeneric species, clarifying evolutionary karyotype trends of these fish groups.(AU)

Alguns peixes pelágicos de grande porte são alvos preferenciais para a pesca esportiva e comercial. Apesar de sua importância econômica, os dados citogenéticos sobre seus processos evolutivos e de manejo são muito deficientes, principalmente devido às dificuldades logísticas. Aqui são apresentadas informações cromossômicas de duas espécies carismáticas, o tarpão, Megalops atlanticus (Elopiformes: Megalopidae), e o agulhão-vela, Istiophorus platypterus (Istiophoriformes: Istiophoridae), ambos com ampla distribuição no oceano Atlântico. Os dados citogenéticos foram obtidos usando métodos convencionais (coloração em Giemsa, técnica de Ag-NORs e bandamento C), coloração com fluorocromos específicos e hibridização fluorescente in situ (FISH) com sondas DNAr. Megalops atlanticus possui 2n = 50 cromossomos, todos acrocêntricos (NF = 50), enquanto Istiophorus platypterus possui 2n = 48 cromossomos, 2m + 2st + 44a (NF = 52). Populações de M. atlanticus do Atlântico Sul e Caribe compartilham padrões cariotípicos idênticos, provavelmente associados ao fluxo gênico entre regiões. Por sua vez, I. platypterus apresenta semelhanças cariotípicas micro e macroestruturais com grupos filogeneticamente próximos, como Carangidae. As características cromossômicas destas espécies destacam seus caminhos evolutivos independentes. Adicionalmente, os dados apresentados contribuem com novos aspectos da fauna pelágica e apoiarão futuros estudos comparativos com espécies congenéricas, esclarecendo as tendências evolutivas do cariótipo destes grupos de peixes.(AU)

Cytogenetical studies in five Atlantic Anguilliformes fishes

The order Anguilliformes comprises 15 families, 141 genera and 791 fish species. Eight families had at least one karyotyped species, with a prevalence of 2n = 38 chromosomes and high fundamental numbers (FN). The only exception to this pattern is the family Muraenidae, in which the eight species analyzed presented 2n = 42 chromosomes. Despite of the large number of Anguilliformes species, karyotypic reports are available for only a few representatives. In the present work, a species of Ophichthidae, Myrichthys ocellatus (2n = 38; 8m+14sm+10st+6a; FN = 70) and four species of Muraenidae, Enchelycore nigricans (2n = 42; 6m+8sm+12st+16a; FN = 68), Gymnothorax miliaris (2n = 42; 14m+18sm+10st; FN = 84), G. vicinus (2n = 42; 8m+6sm+28a; FN = 56) and Muraena pavonina (2n = 42; 6m+4sm+32a; FN = 52), collected along the Northeastern coast of Brazil and around the St Peter and St Paul Archipelago were analyzed. Typical large metacentric chromosomes were observed in all species. Conspicuous polymorphic heterochromatic regions were observed at the centromeres of most chromosomes and at single ribosomal sites. The data obtained for Ophichthidae corroborate the hypothesis of a karyotypic diversification mainly due to pericentric inversions and Robertsonian rearrangements, while the identification of constant chromosome numbers in Muraenidae (2n = 42) suggests a karyotype diversification through pericentric inversions and heterochromatin processes.

Chromosomal studies of five species of the marine fishes from the Paranaguá Bay and the karyotypic diversity in the marine teleostei of the Brazilian coast

In this study, five species of marine fishes from the Paranaguá Bay in the Brazilian coast were evaluated. Eucinostomus argenteus and Diapterus rhombeus (Gerreidae) presented 48 chromosomes, all of which more acrocentric (FN = 48); Strongylura timucu and S. marina (Belonidae) also presented 48 chromosomes, but with a higher karyotypic complexity than the Gerreidae, 10M+2SM+36A (FN = 60) and 4M+44A (FN = 52), respectively. The fifth species, Mugil curema (Mugilidae), different than the others, presented only 28 chromosomes 20M+4ST+4A (FN = 48). The species presented diversity in the karyotypic macro-structure, which should be relevant for the cytotaxonomy and the evolution of this group of the vertebrate.

Nas últimas décadas tem ocorrido no Brasil um incremento de estudos cariotípicos em peixes marinhos. Atualmente são conhecidos os cariótipos de 118 espécies, distribuídas em 43 famílias e 80 gêneros. Foram estudadas cinco espécies de peixes marinhos do complexo estuarino da Baía de Paranaguá na costa brasileira. Eucinostomus argenteus e Diapterus rhombeus (Gerreidae), apresentaram 48 cromossomos todos acrocêntricos (NF = 48); Strongylura timucu e S. marina (Belonidae) apresentaram 48 cromossomos, porém com complexidade cariotípica maior do que apresentada pelos gerreídeos, 10M+2SM+36A (NF = 60) e 4M+44A (NF = 52), respectivamente. A quinta espécie, Mugil curema (Mugilidae), ao contrário das outras quatro espécies aqui analisadas, apresentou apenas 28 cromossomos 20M+4ST+4A (NF = 48). Apesar da tendência em se verificar um cariótipo constituído por 48 cromossomos em teleósteos marinhos, as espécies aqui analisadas apresentam uma diversidade para a macroestrutura cariotípica a ser considerada para a citotaxonomia e evolução desse grupo de vertebrados.

Chromosomal evidence of population subdivision in the freshwater fish Leporinus elongatus in the Upper Paraná River basin

Cytogenetic analyses performed in populations of the Neotropical freshwater fish Leporinus elongatus of the Upper Paraná River basin showed a chromosome polymorphism involving heterochromatic segments of the nucleolar organizing pair in this species. The NOR-bearing chromosome pair was characterized by two phenotypes identified by the absence (CÕ) or presence (C²) of a heterochromatic segment located in an interstitial position of the long arm in this pair. The meiotic segregation of these variations results in three distinct cytotypes, CÕCÕ, CÕC² and C²C². Both populations were in Hardy-Weinberg equilibrium. Sex-related cytotype divergence was identified and multivariate analyses revealed that the C²C² individuals presented morphometric differentiation relative to body height in relation to the other cytotypes. A chromosome differentiation and a cytotype proportion difference observed between both populations suggest the occurrence of population subdivision within this species along the Upper Paraná River basin. These findings might contribute to the knowledge of the population biology of this fish and for its conservation.

Cytogenetic analysis in western Atlantic snappers (Perciformes, Lutjanidae)

The Lutjanidae or snappers are a family of perciform fishes, mainly marine but with some members living in estuaries and entering fresh water to feed. Some are important food fish. Cytogenetic data for Lutjanidae are scarce. In the present work, we cytogenetically characterized through conventional Giemsa staining techniques, Ag-NOR and C-banding the species Ocyurus chrysurus, Lutjanus analis, L. alexandrei, L. cyanopterus, L. jocu and L. synagris, all found along the Brazilian coast. Karyotype analysis of all six species showed a modal value of 2n = 48 acrocentric chromosomes. Single NORs were found at pericentromeric position on the long arms of the 2nd pair in O. chrysurus, L. alexandrei and L. cyanopterus, on the 5th pair in L. analis and on the 23rd pair in L. synagris. The species L. jocu presented multiple NORs located on the 2nd pair at a pericentromeric region and on the 5th pair at a telomeric region. Heterochromatic blocks were identified at the centromeric region of all chromosomes of the studied species. These results indicate that, despite of the chromosomal stability of this family, a relative structural diversification seems to have occurred in the chromosome evolution of the group. Such diversification was evidenced by divergent number and location of ribosomal sites among species. The NOR-bearing pairs represented an efficient cytotaxonomic marker for most of the analyzed species. The data suggest that the presence of interstitially located single NORs on a large acrocentric pair should represent a basal condition for lutjanids.

Natural triploidy in Leporinus cf. elongatus bearing sex chromosomes

Although several cases of natural triploidy in fish have already been described, spontaneous polyploidy in species with differentiated sex chromosomes are rare. We report the occurrence of a triploid fish (3n = 81) Leporinus cf. elongatus, a species characterized by a highly differentiated ZZ/ZW sex chromosome system, from the São Francisco river. The occurrence of a ZZZ triploid adult indicates the viability of this chromosome constitution in this fish.

Multiple pericentric inversions and chromosomal divergence in the reef fishes Stegastes (Perciformes, Pomacentridae)

Damselfishes (Pomacentridae, Perciformes) occur in all major oceans of the world and, with approximately 320 species, represent one of the most diverse families of marine Teleostei. The taxonomy of these reef fishes is problematic because of the large number of complex species and the range of color patterns they display, which vary among individuals and populations of the same species. In this study, we examined the cytogenetic composition of four species of Stegastes (S. pictus, S. fuscus, S. variabilis and S. leucostictus) found along the coast of Brazil. Stegastes pictus had a chromosomal number of 2n = 48 (14m+28sm+2st+4a, fundamental number (FN) = 92), S. fuscus had 2n = 48 (20m+22sm+6a, FN = 90), S. variabilis had 2n = 48 (18m+22sm+8a, FN = 88), and S. leucostictus had 2n = 48, (18m+22sm+8a, FN = 88). The nucleolar organizing regions were single and homologous in all of the species, and were located in the interstitial region on the short arm of the first submetacentric pair. The heterochromatin segments were reduced in size and were distributed conservatively over the centromeric and pericentromeric regions of most of the chromosomes. The marked divergence in the number of chromosomal arms, compared to other perciformes (2n = 48, FN = 48), indicated that varying degrees of multiple pericentric inversions had occurred during the karyotypic evolution of the Pomacentridae. Subtle karyotypic differences between S. variabilis and S. leucostictus suggested a recent divergence or that their karyotypes were less susceptible to changes. These results indicate that cytogenetic analyses could provide important complementary data for the characterization of populations and species of Stegastes and damselfishes in general.

Robertsonian rearrangements in the reef fish Chromis (Perciformes, Pomacentridae) involving chromosomes bearing 5s rRNA genes

Cytogenetic studies were done on three Pomacentridae species of the genus Chromis. The karyotype of C. multilineata consisted of 48 acrocentric chromosomes (FN = 48), C. insolata had 2n = 46-47 (3-4M+6SM+36-38A; FN = 56) and C. flavicauda had 2n = 39 (9M+6SM+24A; FN = 54). Robertsonian polymorphisms were detected in C. insolata and C. flavicauda. All three species had small heterochromatic blocks restricted to centromeric regions. Nucleolar organizer regions (NORs) were detected in the telomeric position of a medium acrocentric chromosome pair in C. multilineata and in non-homologous chromosomes in both C. flavicauda and C. insolata. FISH with a telomeric probe detected no internal telomeric sequences in C. flavicauda and C. insolata. 5S rRNA genes were observed in a pericentromeric region of two large metacentric chromosome pairs in C. flavicauda and two large acrocentric pairs in C. insolata. The karyotype structure and the number and location of the 5S rDNA loci in these two species indicated that the 5S rRNA-bearing acrocentric chromosomes were directly involved in the origin of the polymorphisms observed. These data reinforce the idea that Robertsonian rearrangements have been involved in molding the karyotype in the subfamily Chrominae