Abstract Recently renamed, Psalidodon scabripinnis populations of Serra da Mantiqueira, previously known as Astyanax scabripinnis have been deeply studied in the last years. These populations are small and isolated and occur very close to the watershed between Paraíba do Sul River basin and Upper Paraná River basin, in Serra da Mantiqueira region in the Atlantic Rainforest. These conditions arouse the interest in knowing theor genetic conservation status and how they responded to the separation between the two rivers basins. Therefore, we accessed the genetic diversity of five P. scabripinnis populations of this region with microsatellites and mitochondrial data. The results showed a complex structure pattern that doesn’t match the simple basin separation and a reasonably conservation status when compared with other populations of the same family or with similar natural history.

RESUMO - RACIONAL: O diabetes tipo 2 (DM2) é uma doença de impacto mundial que tem levado ao aumento de comorbidades e mortalidade em vários países. A imunoexpressão dos hormônios incretínicos glp-1 e pyy3-36, pode ser usada como marcador no trato gastrointestinal para analisar a atividade da célula L em resposta ao tratamento do DM2. OBJETIVO: O presente estudo teve como objetivo investigar a presença, localização e secreção de células L no intestino delgado de pacientes submetidos à forma de cirurgia bariátrica denominada gastroenteromentectomia adaptativa com bipartição parcial. MÉTODOS: Ensaios imunohistoquímicos, reação quantitativa em cadeia de polimerase em tempo real (qPCR) e análise de manchas ocidentais foram realizados em amostras de mucosa intestinal de pacientes com diabetes tipo 2 nos períodos pré- e pós-operatório. RESULTADOS: Todos os resultados foram consistentes e indicaram expressão basal e secreção de peptídeos glucagon-1 (GLP-1) e peptídeos YY (PYY3-36) incretinas por células L. Uma maior densidade de células foi demonstrada nas porções mais distais do intestino delgado. Não foi encontrada diferença significativa entre os níveis de expressão GLP-1 e PYY3-36 nos períodos pré-operatório e pós-operatório, provavelmente devido ao estado de jejum prolongado durante o qual as amostras foram coletadas CONCLUSÃO: O maior número de células L em atividade implica melhor sinalização de peptídeo, resposta e funcionamento do sistema neuroendócrino.

ABSTRACT - BACKGROUND: Type 2 diabetes mellitus (T2DM) is a disease of global impact that has led to an increase in comorbidities and mortality in several countries. Immunoexpression of the incretin hormones such as glucagon-like peptide-1 (GLP-1) and peptide YY (3-36) (PYY3-36) can be used as a scorer in the gastrointestinal tract to analyze L-cell activity in response to T2DM treatment. OBJECTIVE: This study aimed to investigate the presence, location, and secretion of L cells in the small intestine of patients undergoing the form of bariatric surgery denominated adaptive gastroenteromentectomy with partial bipartition. METHODS: Immunohistochemical assays, quantitative real-time polymerase chain reaction (qPCR), and Western blot analysis were performed on samples of intestinal mucosa from patients with T2DM in both the preoperative and postoperative periods. RESULTS: All results were consistent and indicated basal expression and secretion of GLP-1 and PYY3-36 incretins by L cells. A greater density of cells was demonstrated in the most distal portions of the small intestine. No significant difference was found between GLP-1 and PYY3-36 expression levels in the preoperative and postoperative periods because of prolonged fasting during which the samples were collected. CONCLUSION: The greater number of L cells in activity implies better peptide signaling, response, and functioning of the neuroendocrine system.

Abstract The aims of this study were to evaluate the homology of the ZmMATE1 and ZmMATE2 gene sequences with those deposited in the international banks of sequences and quantify the differential expression of the genes ZmMATE1, ZmMATE2, and ZmNrat1 in germplasms of landrace and hybrid maize under aluminum (Al) stress in minimal solution. Fifty-two hybrids from different companies and 50 landrace varieties were genotyped for the genes ZmMATE1 and ZmMATE2. For studies of gene expression, the tolerant (H 44 and V 18) and the sensitive (H 22 and V 25) genotypes were exposed to minimal solution containing 4 mg L-1 of Al for different periods (0, 1, 3, 6, 9, 12, 24, and 48 h). The results showed greater differential expression in the tolerant V 18 landrace variety of the gene ZmMATE1, indicating that exudation of citrate may be the main mechanism of Al tolerance in this genotype.

Abstract The objectives of this study were to map genomic regions associated with QTL for aluminum (Al) tolerance in maize and determine the phenotypic effects of tolerance loci. QTL analysis for Al tolerance was carried out in a population of F2:3 progenies resulting from a cross between the contrasting lines LT 99-4 and LS 04-2. SSR (Simple Sequence Repeat) loci and AFLP (Amplified Fragment Length Polymorphism) were used to construct the linkage map and to detect QTL mapped by composite interval mapping analysis. Nine tolerance QTL among eight linkage groups (chromosomes 2, 4, 5, 6, 7, 8, 9, and 10) were mapped, which explained 70.3% of the phenotypic variance. The results confirmed three major QTL (bins 6.00, 8.05, and 10.01) that are described in the literature for Al tolerance, which accounted for most of the phenotypic variance (40.3%).

Abstract Background Among Neotropical fishes, the family Characidae is highly diverse and speciose and its taxonomy is not completely resolved. In Chile, the family is represented by five species, all within the genus Cheirodon , of which C. pisciculus, C. galusdae, C. kiliani , and C. australe are endemic , while C. interruptus is introduced. We compared chromosomal markers in order to appreciate the taxonomy and evolution of these trans-Andean fishes. Results The specimens were photographed in stereomicroscope to observe the ventral protrusive teeth and cusps for morphological analysis and species identification. All of the species analysed had equally diploid chromosome number 2n = 50, with karyotypes dominated by high number of acrocentric chromosomes as compared to those of other members of Cheirodontinae. The distribution of heterochromatin was inconspicuous and was similar in all the species. The number of active NORs (nucleolus organizer regions) was polymorphic, with the greater number of them in C. kiliani and C. galusdae . The location of 5S and 18S rDNA ranged in number and position, showing two sites in different chromosomes. The fluorescent in situ hybridization with telomeric probe did not reveal interstitial sites in all analysed species. Conclusions The comparative analysis of karyotypes and morphological markers revealed a biogeographic pattern of distribution, with the species that occur in the southern region forming one group and those in central and northern Chile forming another.

Objective The aim of this study was to evaluate the genetic expression of adipokines in the adipocytes of monosodium glutamate (MSG)-treated obese rats submitted to physical activity.Materials and methods Obesity was induced by neonatal MSG administration. Exercised rats (MSG and control) were subjected to swim training for 30 min for 10 weeks, whereas their respective controls remained sedentary. Total RNA was obtained from sections of the mesenteric adipose tissue of the rats. mRNA levels of adiponectin (Adipoq), tumor necrosis factor alpha (Tnf), peroxisome proliferator-activated receptor alpha (Ppara), and peroxisome proliferator-activated receptor gamma (Pparg) adipokines were quantified by quantitative Real-Time Polymerase Chain Reaction (qRT-PCR).Results In the exercise-trained control group, the expression of Adipoq increased compared to the sedentary control, which was not observed in the MSG-obese rats. Increased levels of Tnf in MSG-obese rats were not reversed by the swim training. The expression of Ppara was higher in sedentary MSG-obese rats compared to the sedentary control. Swimming increased this adipokine expression in the exercise-trained control rats compared to the sedentary ones. mRNA levels of Pparg were higher in the sedentary MSG-rats compared to the sedentary control; however, the exercise did not influenced its expression in the groups analyzed.Conclusions In conclusion, regular physical activity was not capable to correct the expression of proinflammatory adipokines in MSG-obese rat adipocytes.

Dados cariotípicos são apresentados para quatro espécies da família Pimelodidae. Todas apresentaram o mesmo número diploide, 2n = 56 cromossomos, com diferenças nas fórmulas cariotípicas. As espécies aqui analisadas mostraram pouca quantidade de heterocromatina localizada preferencialmente na região centromérica e telomérica de alguns cromossosmos do complemento cariotípico. As regiões organizadoras de nucléolo (Ag-RONs) e a localização dos genes ribossomais pela hibridização in situ fluorescente (FISH), com sondas 18S e 5S, evidenciaram somente um par cromossômico marcado portador de genes ribossomais, à exceção de Pimelodus britskii que apresentou NORs múltiplas e localização sintênica das sondas 18S e 5S. Eventos não-Robertsonianos, como inversão pericêntrica e duplicação das NORs são requeridos para explicar a diversificação cariotípica em Pseudoplatystoma do rio Paraguai (MS), Pimelodus do rio Iguaçu (PR), Sorubim do rio Paraguai (MS) e Steindachneridion do rio Paraíba do Sul (SP). Os dados obtidos para a macroestrutura cariotípica destas espécies corrobora um padrão conservado observado na família Pimelodidae. Por outro lado, evidências de variações interespecíficas pelos marcadores de citogenética molecular empregados possibilitam inferências citotaxonômicas e diferenciação das espécies aqui analisadas.

Karyotypic data are presented for four species of fish belonging to the Pimelodidae family. These species show a conserved diploid number, 2n = 56 chromosomes, with different karyotypic formulae. The analyzed species showed little amount of heterochromatin located preferentially in the centromeric and telomeric regions of some chromosomes. The nucleolus organizer regions activity (Ag-NORs) and the chromosomal location of ribosomal genes by fluorescent in situ hybridization (FISH), with 18S and 5S probes, showing only one chromosome pair marked bearer of ribosomal genes, the only exception was Pimelodus britskii that presented multiple NORs and syntenic location of the 18S and 5S probes. Non-Robertsonian events, as pericentric inversion and NORs duplication are requested to explain the karyotype diversification in Pseudoplatystoma from the rio Paraguay (MS), Pimelodus from the rio Iguaçu (PR), Sorubim from the rio Paraguay (MS) and Steindachneridion from the rio Paraíba do Sul (SP). The obtained data for the karyotype macrostructure of these species corroborates a conserved pattern observed in Pimelodidae. On the other hand, interspecific variations detected by molecular cytogenetics markers made possible cytotaxonomic inferences and differentiation of the species here analyzed.

Cytogenetic analysis of Astylus antis using mitotic and meiotic cells was performed to characterize the haploid and diploid numbers, sex determination system, chromosome morphology, constitutive heterochromatin distribution pattern and chromosomes carrying nucleolus organizer regions (NORs). Analysis of spermatogonial metaphase cells revealed the diploid number 2n = 18, with mostly metacentric chromosomes. Metaphase I cells exhibited 2n = 8II+Xyp and a parachute configuration of the sex chromosomes. Spermatogonial metaphase cells submitted to C-banding showed the presence of small dots of constitutive heterochromatin in the centromeric regions of nearly all the autosomes and on the short arm of the X chromosome (Xp), as well as an additional band on one of the arms of pair 1. Mitotic cells submitted to double staining with base-specific fluorochromes (DAPI-CMA3) revealed no regions rich in A+T or G+C sequences. Analysis of spermatogonial mitotic cells after sequential Giemsa/AgNO3 staining did not reveal any specific mark on the chromosomes. Meiotic metaphase I cells stained with silver nitrate revealed a strong impregnation associated to the sex chromosomes, and in situ hybridization with an 18S rDNA probe showed ribosomal cistrons in an autosomal bivalent.

In this work we describe the cytogenetic analyses performed in specimens of Astylus variegatus (Germar, 1824) collected in two localities: one area of natural vegetation and one of agricultural crops, where agrochemical products were used. Astylus variegatus had karyotypes with 2n(male) = 16+Xy p and 2n (female) = 16+XXp, with exclusively metacentric chromosomes. Pachytene spermatocytes showed synapsed autosomal bivalents and non-associated sex chromosomes. In diplotene, the autosomal bivalents exhibited one or two terminal chiasmata and the Xy p had a typical parachute configuration. In meiotic cells of some specimens, an extra chromosome, interpreted as a B chromosome, was observed. C-banding showed constitutive heterochromatin in the pericentromeric region of all chromosomes, with the exception of the y p. Silver nitrate staining revealed one nucleolus organizer region (NOR) on the terminal region of the short arm of the second autosome pair. Silver staining of meiotic cells confirmed the NOR pattern detected in mitotic cells and revealed an argentophilous material on the Xy p. A cytogenetic comparison between the two populations of A. variegatus showed a statistically significant divergence (chi2 = 117.10; df = 1) in the number of aneuploid cells and a higher frequency of B chromosome in the population exposed to agrochemicals.

Quatro populações de Astyanax aff. fasciatus do alto rio Tibagi (município de Ponta Grossa, Paraná, Brasil) foram citogeneticamente e morfometricamente analisadas. Os dados citogenéticos mostram a ocorrência de distintos cariótipos (citótipos), aqui nomeados citótipo A, com 2n=48 (6m+18sm+14st+10a), citótipo B, com 2n=50 (8m+18sm+14st+10a) e citótipo C, com 2n=50 cromossomos (8m+18sm+14st+10a). O padrão de distribuição da heterocromatina constitutiva foi muito similar entre os citótipos A e B, mas mostrou-se divergente em relação ao citótipo C. Citótipos distintos podem ocorrer em simpatria na região do alto rio Tibagi, com exceção da amostra da Furna 2, a qual apresenta somente o citótipo A exclusivamente. Além disso, um exemplar com 2n=49 cromoossomos (7m+18sm+14st+10a) foi também encontrado e, pelas características apresentadas, pode ser uma conseqüência de um raro evento de hibridização entre os citótipos A e B. As análises morfométricas de variáveis canônicas indicam um isolamento consistente da amostra da Furna 2 enquanto as demais amostras analisadas se apresentam sobrepostas indicando um possível fluxo gênico ou evento de isolamento recente. Este modelo aponta para um complexo de espécies crípticas na região estudada.

Four populations of Astyanax aff. fasciatus of the upper rio Tibagi (municipal district of Ponta Grossa, Paraná State, Brazil), had their karyotypes and morphometry analyzed. The cytogenetic data show the occurrence of distinct karyotypes (cytotypes), here named cytotype A, with 2n=48 chromosomes (6m+18sm+14st+10a), cytotype B, with 2n=50 chromosomes (8m+18sm+14st+10a) and cytotype C, with 2n=50 chromosomes (8m+18sm+14st+10a). The distribution pattern of the constitutive heterochromatin was very similar between cytotypes A and B, but diverged in relation to cytotype C. Distinct cytotypes may occur in sympatry in the upper rio Tibagi region, with the exception of the Furna 2 sample, which presents cytotype A exclusively. In addition, a specimen with 2n=49 chromosomes (7m+18sm+14st+10a) was also found and, by the characteristics presented, may be a consequence of a rare hybridization event between cytotypes A and B. The morphometric analyses of canonical variates indicate a consistent isolation of the Furna 2 sample, while the other samples seem to be superimposed, indicating a possible gene flow or even a recent isolation event. This model points to a probable complex of cryptic species in the studied region.

Species of the subtribe Oedionychina not only have a highly uniform diploid number of 2n = 22 (20+X+y) but have the karyotypic peculiarity of possessing extremely large sex chromosomes. We analyzed Paranaita opima embryos and gonadal cells to determine their diploid number, chromosomal morphology, type of sex determination system, constitutive heterochromatin pattern and which chromosomes bear nucleolus organizer regions (NORs). The diploid number of P. opima was 2n = 22 (20+XY/XX) with all chromosomes being metacentric. Chromosome pair 6 showed an interstitial secondary constriction on the short arm. The C-banding technique revealed centromeric constitutive heterochromatin in all chromosomes, which, in pair 6, extended up to the secondary constriction of the short arm, additional C-bands also being present on the Y chromosome. Silver nitrate nucleolar organizer region (Ag-NOR) staining showed NORs on the secondary constriction of pair 6. Fluorochrome analysis with chromomycin A3 (CMA3), 4'-6-diamidino-2-phenylindole (DAPI) and the distamycin A (DA) counterstain showed that the short arm of chromosome pair 6 exhibited a GC-rich block extending from the proximal to the median region, including part of the secondary constriction. The same techniques also showed AT-rich blocks at the centromeric region of all chromosomes and at the terminal region of the short arm of pair 6. The basic karyotype characteristics and C band pattern of P. opima are similar to those described for other species in the subtribe Oedionychina. The pattern of autosomal NORs observed in P. opima corresponds to that registered in the majority of the Chrysomelidae species.

We used differential staining techniques (BSG, GTG, AgNO3, DAPI and CMA3 banding) and fluorescent in situ hybridization (FISH) with 5S and 18S probes to investigated the karyotypic and cytogenetic chracteristics of Prochilodus lineatus specimens from a population in Vila Velha state park (Parque Estadual de Vila Velha, Ponta Grossa, Paraná state, southern Brazil). The specimens studied showed the same karyotype as that found in other P. lineatus populations, i.e. 2n = 54 biarmed chromosomes (40m + 14 sm) and c-positive heterochromatin preferentially located pericentromerically in all chromosomes. The presence of partial or totally heterochromatic supernumerary chromosomes with numeric intra-individual variation was confirmed in the analyzed population. The nucleolar organizing regions (NORs) were interstitially situated on the long arm of chromosome pair 4 directly beneath the centromere. The differential banding techniques and FISH revealed NOR size polymorphism due to structural events such as breaks and duplication of the larger rDNA site cluster. We also observed syntenic localization of the 5S ribosomal genes in the distal segment of the 45S cluster.