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DNA sequences have proved valuable for associating males and females of the same dimorphic species in Hymenoptera. These molecular associations, however, depend on the used DNA sequences and the analysis methods. In the present study, we evaluated the molecular associations on 23 species of Dissomphalus (Hymenoptera, Bethylidae) using the three most common DNA sequences in molecular studies of Hymenoptera (28S rRNA, COI and ITS2). Our results indicated the male-female association with these three markers. COI, however, showed to be more suitable than the other markers because there was no overlap of genetic variation among species. In contrast, the 28S rRNA showed overlapping of genetic distance limits, indicating that the distance matrix is not enough to assign a sexual conspecificity. We were able to perform female association to the described species D. verus Mugrabi & Azevedo, demonstrating that phylogenetic analysis is a valuable tool for associating the sexes of dimorphic species.

The Neotropical region hosts 4225 freshwater fish species, ranking first among the world's most diverse regions for freshwater fishes. Our NEOTROPICAL FRESHWATER FISHES data set is the first to produce a large-scale Neotropical freshwater fish inventory, covering the entire Neotropical region from Mexico and the Caribbean in the north to the southern limits in Argentina, Paraguay, Chile, and Uruguay. We compiled 185,787 distribution records, with unique georeferenced coordinates, for the 4225 species, represented by occurrence and abundance data. The number of species for the most numerous orders are as follows: Characiformes (1289), Siluriformes (1384), Cichliformes (354), Cyprinodontiformes (245), and Gymnotiformes (135). The most recorded species was the characid Astyanax fasciatus (4696 records). We registered 116,802 distribution records for native species, compared to 1802 distribution records for nonnative species. The main aim of the NEOTROPICAL FRESHWATER FISHES data set was to make these occurrence and abundance data accessible for international researchers to develop ecological and macroecological studies, from local to regional scales, with focal fish species, families, or orders. We anticipate that the NEOTROPICAL FRESHWATER FISHES data set will be valuable for studies on a wide range of ecological processes, such as trophic cascades, fishery pressure, the effects of habitat loss and fragmentation, and the impacts of species invasion and climate change. There are no copyright restrictions on the data, and please cite this data paper when using the data in publications., (© 2022 The Ecological Society of America.)

Glans penis morphology has been used as a powerful tool in mammal taxonomy to differentiate cryptic species. Neotropical rodent species Akodoncursor and A.montensis are cryptic, and interspecific hybrids are like their parental species. We investigated non-metric and metric phallic characters aiming to differentiate A.cursor from A.montensis . We also evaluated the parental species' influence of the phallic characters on hybrids. We analysed 96 male adults-56 A.cursor , 27 A.montensis , and 13 hybrids, subgrouping species by locality and hybrids by parental species (paternal vs maternal). We verified that A.cursor and A.montensis are distinguishable by penile-shape morphology: A.cursor has an elongated penile form with a flare in the distal portion and A.montensis has a barrel-shaped form. Also, dark spots in ventral view, if present in A.montensis , distinguish A.montensis from A.cursor . Although the non-metric characters differentiate the species, they do not distinguish the subgroups of A.cursor , A.montensis , and hybrids. The metric phallic characters indicated a significant difference between species and hybrids. These characters also differentiate the population groups of A.cursor . However, A.montensis subgroups and hybrids subgroups did not present a significant difference. This study shows the importance of penis morphology in the taxonomy of the cryptic rodent species A.cursor and A.montensis , representing a powerful tool to discriminate male specimens in mammal collections without karyotyping or sequencing, even though the specimens occurred in sympatric areas. Since most taxidermy protocols do not preserve the penis in mammal preparations, liquid preservation of some specimens or the removal of the penis before taxidermy for liquid preservation could be beneficial. We also recommend the organisation in museum collections of a penis bank for the A.cursor species group (or even all rodent species) to avoid losing this important information for species identification., (Leonardo Campana, Letícia Rosário Cruz, Roberta Paresque, Valéria Fagundes.)

In this study, the perception of Brazilians regarding COVID-19 in 12 cities in the country was analyzed. Issues about the severity and dangers of the disease, sources of information and reliability, checking information, attitudes, precautions, and priorities for coping and trusting relationships in science were addressed. This study was carried out in the context of broader research on how Brazilians perceive the Oswaldo Cruz Foundation (Fiocruz). The survey was applied between May 18 and June 10, 2020, with 1,643 residents over 16 years of age in Brazilian cities where Fiocruz has a technical unit or office. The results reveal that the majority of the interviewees appreciate the seriousness of the pandemic, the importance of being properly informed, considers the measures indicated by health authorities important and trusts scientists and scientific institutions as sources of information. With the sense of urgency and experience of uncertainties about the present and the future, the need for strengthening of trust in institutions is present.

Dissomphalus is a cosmopolitan genus of Bethylidae and has 269 Neotropical species divided into 32 species-groups, mostly defined by the genital and the tergal process structures. Dissomphalus rectilineus and D. concavatus are sympatric species in the ulceratus species-group. Members of the species-group share many similarities in the morphology of the head, hypopygium, tergal process and genitalia, but may be distinguished by the structure of the hypopygium. Previous studies have found intermediate structures of the hypopygium in the sympatric areas and raised questions about the distinctiveness of these two species. We sequenced 340 bp of the mitochondrial gene cytochrome oxidase I of 29 specimens from Brazil and Paraguay, calculated the genetic divergence among specimens, and recovered the phylogenetic relationships between taxa. In addition, we compared the morphology of the hypopygium to evaluate its use as a species-specific diagnostic character using the genetic divergence values. We recovered three well-supported monophyletic groups (intraclade divergence from 1.3 to 13.4%) and three hypopygium morphologies associated with each clade, two of them associated with D. rectilineus and D. concavatus (as described in the literature); the third one is new, not associated with any known species. The divergence between the D. rectilineus and D. concavatus clades was 19%, while the third clade is divergent from each species by 19-20%. If fully described, the hypopygium shape associated with the COI sequence will represent an extremely promising approach to the diagnosis of Dissomphalus species., (Marina Monjardim, Celso O. Azevedo, Valeria Fagundes.)

Introduction: A strong association between stroke and atrial fibrillation (AF) has been demonstrated. Anticoagulation for the prevention of stroke in high-risk patients has the benefit of improving the life expectancy, quality of life, autonomy and social functioning of the patient. The COVID-19 pandemic poses challenges for stroke patients because of the association between SARS-CoV-2 infection and thromboembolic risk., Case Description: We describe the case of an 84-year-old female patient admitted due to an embolic stroke and non-anticoagulated AF. Her admission symptoms were sensory-motor aphasia and severe right limb paresis with an NIHSS score of 24. The diagnosis of embolic stroke (namely, total anterior circulation infarct; TACI) was made. Her stroke was extensive so she was not started on anticoagulation. During hospitalization, new embolic events occurred and a concomitant diagnosis of COVID-19 was made with progressive respiratory dysfunction followed by multiorgan failure. The patient died despite appropriate treatment., Discussion: The prognosis of elderly patients with cardioembolic stroke depends on anticoagulation administration. The NIHSS score on admission of our patient meant anticoagulation therapy was not appropriate. The diagnosis of COVID-19 contributed to the patient's death., Learning Points: Anticoagulation should be considered in stroke patients with total infarction and atrial fibrillation.There is an association between COVID-19 and thromboembolic stroke.Elderly patients with stroke and COVID-19 are at higher risk of death., Competing Interests: Conflicts of Interests: The Authors declare that there are no competing interests., (© EFIM 2020.)

Introduction: Lumbar epidural anaesthesia is a commonly used technique for analgesia during labour. One of the rare complications of this technique is pneumocephalus., Case Description: We report the case of a 35-year-old female admitted to the Emergency Department with severe headache associated with fast head movements. Five days previously she had a eutocic delivery and lumbar epidural anaesthesia was performed. A brain computed tomography (CT) scan showed pneumocephalus and she was admitted to the hospital ward. A brain CT scan on the fourth day of hospitalization showed resolution of ventricular pneumocephalus., Discussion: The most frequently occurring symptom with pneumocephalus is headache associated with fast brain motion resulting from air injection and meningeal irritation. When there is clinical suspicion of pneumocephalus, a brain CT scan should be performed for the diagnosis., Learning Points: Pneumocephalus is the presence of air in the intracranial cavity and its development after spinal or epidural anaesthesia is extremely infrequent.Headache that occurs in the setting of lumbar epidural anaesthesia should not be labelled as post-dural puncture headache.The suspicion of pneumocephalus, based on the characteristics of the headache, should be maintained to obtain an emergent brain CT scan., Competing Interests: Conflicts of Interests: The Authors declare that there are no competing interests., (© EFIM 2020.)

The taxonomy of muriquis, the largest extant primates in the New World, is controversial. While some specialists argue for a monotypic genus (Brachyteles arachnoides), others favor a two-species classification, splitting northern muriquis (Brachyteles hypoxanthus) from southern muriquis (B. arachnoides). This uncertainty affects how we study the differences between these highly endangered and charismatic primates, as well as the design of more effective conservation programs. To address this issue, between 2003 and 2017 we collected over 230 muriqui fecal samples across the genus' distribution in the Brazilian Atlantic Forest, extracted DNA from these samples, and sequenced 423 base pairs of the mitochondrial DNA (mtDNA) control region. Phylogenetic and species delimitation analyses of our sequence dataset robustly support two reciprocally monophyletic groups corresponding to northern and southern muriquis separated by an average 12.7% genetic distance. The phylogeographic break between these lineages seems to be associated with the Paraíba do Sul River and coincides with the transition between the north and south Atlantic Forest biogeographic zones. Published divergence estimates from whole mitochondrial genomes and nuclear loci date the split between northern and southern muriquis to the Early Pleistocene (ca. 2.0 mya), and our new mtDNA dataset places the coalescence time for each of these two clades near the last interglacial (ca. 120-80 kya). Our results, together with both phenotypic and ecological differences, support recognizing northern and southern muriquis as sister species that should be managed as distinct evolutionarily significant units. Given that only a few thousand muriquis remain in nature, it is imperative that conservation strategies are tailored to protect both species from extinction., (© 2019 Wiley Periodicals, Inc.)

Heyde's syndrome is a form of acquired von Willebrand syndrome that consists of bleeding from intestinal angiodysplasia in the presence of aortic stenosis (AS). An association with obstructive hypertrophic cardiomyopathy, rather than AS, by a similar mechanism has also been described. We report the case of a 78-year-old woman with chronic anaemia and hypertrophic obstructive cardiomyopathy in whom intestinal angiodysplasia with active bleeding was identified by an unconventional method. In this case, the authors describe a different approach to reach the correct diagnosis., Learning Points: In patients with anaemia due to gastrointestinal bleeding, a high level of suspicion is crucial to identify the haemorrhagic focus.Intestinal angiodysplasia is associated with acquired von Willebrand syndrome.Acquired von Willebrand syndrome secondary to hypertrophic obstructive cardiomyopathy occurs by the same mechanism of aortic stenosis., Competing Interests: Conflicts of Interests: The Authors declare there are no competing interests.

Botulism is rare neuroparalytic disease caused by botulinum toxin, one of the most toxic substances known. Foodborne botulism is caused by consumption of foods contaminated with botulinum toxin. The clinical manifestations are flaccid, symmetrical, descending paralysis affecting cranial and peripheral nerves. The only specific treatment is botulinum antitoxin. We report the case of a 37-year-old man with gastrointestinal manifestations and posterior cranial nerve palsy who was diagnosed with botulism infection. Clinicians should be aware of rare causes of infection and determine the aetiology of symptoms., Learning Points: Botulism remains a diagnostic challenge.Misdiagnosis of early cases suggests sporadic cases are overlooked.Timely clinical diagnosis is critical for treatment decisions as botulinum antitoxin cannot reverse existing paralysis., Competing Interests: Conflicts of Interests: The Authors declare that there are no competing interests.

Genitalia are rich source of characters in insect taxonomy. Usually, they are examined after dissection and cleaning with potassium hydroxide (KOH), procedure that may damage both genital morphological structures and intracellular molecular contents. Enzymatic procedure with Proteinase K has been used to clean muscle off the genitalia while extract DNA, but its damage to the genital structures has not been evaluated. Herein, we qualitatively compare the use of KOH and Proteinase K to prepare genital structures in minute insects (Hymenoptera: Bethylidae). We show that Proteinase K is better to preserve the genital structure and provides quality DNA.

The forest refuge hypothesis (FRH) has long been a paradigm for explaining the extreme biological diversity of tropical forests. According to this hypothesis, forest retraction and fragmentation during glacial periods would have promoted reproductive isolation and consequently speciation in forest patches (ecological refuges) surrounded by open habitats. The recent use of paleoclimatic models of species and habitat distributions revitalized the FRH, not by considering refuges as the main drivers of allopatric speciation, but instead by suggesting that high contemporary diversity is associated with historically stable forest areas. However, the role of the emerged continental shelf on the Atlantic Forest biodiversity hotspot of eastern South America during glacial periods has been ignored in the literature. Here, we combined results of species distribution models with coalescent simulations based on DNA sequences to explore the congruence between scenarios of forest dynamics through time and the genetic structure of mammal species cooccurring in the central region of the Atlantic Forest. Contrary to the FRH predictions, we found more fragmentation of suitable habitats during the last interglacial (LIG) and the present than in the last glacial maximum (LGM), probably due to topography. We also detected expansion of suitable climatic conditions onto the emerged continental shelf during the LGM, which would have allowed forests and forest-adapted species to expand. The interplay of sea level and land distribution must have been crucial in the biogeographic history of the Atlantic Forest, and forest refuges played only a minor role, if any, in this biodiversity hotspot during glacial periods.

Using complete mitochondrial genome sequences, we provide the first molecular analysis of the phylogenetic position of the yellow-tailed woolly monkey, Lagothrix flavicauda (a.k.a. Oreonax flavicauda), a critically endangered neotropical primate endemic to northern Perú. The taxonomic status and phylogenetic position of yellow-tailed woolly monkeys have been debated for many years, but in this study both Bayesian and maximum likelihood phylogenetic reconstructions unequivocally support a monophyletic woolly monkey clade that includes L. flavicauda as the basal taxon within the radiation. Bayesian dating analyses using several alternative calibrations suggest that the divergence of yellow-tailed woolly monkeys from other Lagothrix occurred in the Pleistocene, ∼2.1Ma, roughly 6.5 my after the divergence of woolly monkeys from their sister genus, Brachyteles. Additionally, comparative analysis of the cytochrome oxidase subunit 2 (COX2) gene shows that genetic distances between yellow-tailed woolly monkeys and other Lagothrix from across the genus' geographic distribution fall well within the range of between-species divergences seen in a large number of other platyrrhine primate genera at the same locus and outside the range of between-genus divergences. Our results thus confirm a position within Lagothrix for the yellow-tailed woolly monkey and strongly suggest that the name Oreonax be formally considered a synonym for this genus. This revision in taxonomic status does not change the dire conservation threats facing the yellow-tailed woolly monkey in Perú, where the remaining wild population is estimated at only ∼10,000 individuals living in a highly fragmented landscape., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Objective: The objective of this study was to evaluate the sleep quality, sleepiness, chronotype and the anxiety level of Brazilian Paralympics athletes before the 2008 Beijing Paralympic Games., Design: Cross-sectional study. Setting Exercise and Psychobiology Studies Center (CEPE) and Universidade Federal de São Paulo, an urban city in Brazil., Participants: A total of 27 Paralympics athletes of both genders (16 men and 11 women) with an average age of 28±6 years who practised athletics (track and field events) were evaluated., Main Outcome Measures: Sleep quality was evaluated using the Pittsburgh Scale and the Epworth Sleepiness Scale to evaluate sleepiness. Chronotype was determined by the Horne and Östberg questionnaire and anxiety through the State-Trait Anxiety Inventory. The evaluations were performed in Brazil 10 days before the competition., Results: The study's results demonstrate that 83.3% of the athletes that presented excessive daytime sleepiness also had poor sleep quality. The authors noted that 71.4% were classified into the morning type and 72% of the athletes who presented a medium anxiety level also presented poor sleep quality. Athletes with poor sleep quality showed significantly lower sleep efficiency (p=0.0119) and greater sleep latency (p=0.0068) than athletes with good sleep quality. Athletes who presented excessive daytime sleepiness presented lower sleep efficiency compared to non-sleepy athletes (p=0.0241)., Conclusions: The authors conclude that the majority of athletes presented poor sleep quality before the competition. This information should be taken into consideration whenever possible when scheduling rest, training and competition times.

Blarinomys breviceps possesses cryptic and burrowing habits with poorly documented genetics and life history traits. Due to its rarity, only a few specimens and DNA sequences have been deposited in collections worldwide. Here, we present the most comprehensive cytogenetic and molecular characterization of this rare genus. Phylogenetic analyses based on partial cytochrome b sequences were performed, attempting to establish the relationships among individuals with distinct karyotypes along the geographic distribution of the genus in the Atlantic Forest. Classical and molecular cytogenetics, using banding patterns and FISH of telomeric and whole chromosome X-specific painting probes (obtained from the Akodontini Akodon cursor) were used to characterize and compare the chromosomal complements. Molecular phylogenetic analyses recovered 2 main geographically structured clades, northeastern and southeastern with pairwise sequence divergences among specimens varying between 4.9 and 8.4%. Eight distinct karyomorphs are described: (A) 2n = 52 (50A, XX), (B) 2n = 52 (48A, XY+2Bs), (C) 2n = 45 (42A, XY+1B), (D) 2n = 43 (37A, XX+4Bs), (E) 2n = 37 (34A, XY+1B), (F) 2n = 34 (32A, XX), (G) 2n = 31 (27A, XX+2Bs), (H) 2n = 28 (26A, XY), all with the same number of autosomal arms (FN(A) = 50). Variation of 0-4 supernumerary chromosomes (Bs) presenting heterogeneity in morphology and distribution of interstitial telomeric sequences (ITSs) is reported. ITSs are also found in some metacentric autosomes. The phylogeographic separation between 2 major lineages with high levels of genetic divergence, and the wide karyotypic diversity indicate that B. breviceps is a diverse group that warrants taxonomic re-evaluation., (Copyright © 2012 S. Karger AG, Basel.)

Levels of reproductive skew vary in wild primates living in multimale groups depending on the degree to which high-ranking males monopolize access to females. Still, the factors affecting paternity in egalitarian societies remain unexplored. We combine unique behavioral, life history, and genetic data to evaluate the distribution of paternity in the northern muriqui (Brachyteles hypoxanthus), a species known for its affiliative, nonhierarchical relationships. We genotyped 67 individuals (22 infants born over a 3-y period, their 21 mothers, and all 24 possible sires) at 17 microsatellite marker loci and assigned paternity to all infants. None of the 13 fathers were close maternal relatives of females with which they sired infants, and the most successful male sired a much lower percentage of infants (18%) than reported for the most successful males in other species. Our findings of inbreeding avoidance and low male reproductive skew are consistent with the muriqui's observed social and sexual behavior, but the long delay (≥2.08 y) between the onset of male sexual behavior and the age at which males first sire young is unexpected. The allocation of paternity implicates individual male life histories and access to maternal kin as key factors influencing variation in paternal--and grandmaternal--fitness. The apparent importance of lifelong maternal investment in coresident sons resonates with other recent examinations of maternal influences on offspring reproduction. This importance also extends the implications of the "grandmother hypothesis" in human evolution to include the possible influence of mothers and other maternal kin on male reproductive success in patrilocal societies.

Deltamys Thomas 1917 is a poorly studied and rarely collected taxon of Akodontini (Sigmodontinae). The single described species, Deltamys kempi (DKE), has a basic karyotype with a diploid number of 2n = 37 in males and 2n = 38 in females, a fundamental number FN = 38 for both sexes, and an X(1)X(1)X(2)X(2)/X(1)X(2)Y sex determination system. Herein, a new allopatric form, Deltamys sp. (DSP), is reported, based on specimens from southern Brazil, with 2n = 40, FN = 40 and XX/XY sex chromosomes. We describe the karyotype and mechanism of chromosomal differentiation between both Deltamys complements. Phylogenetic analyses, based on the complete sequence (1,140 bp) of the mitochondrial cytochrome b gene, grouped Deltamys sp. as sister species to D. kempi, with up to 12% genetic divergence between them. The GTG-banding patterns show complete autosomal correspondence between D. kempi and Deltamys sp. and identify a tandem rearrangement involving DSP7, DSP19 and DKE4 that is responsible for the differences in 2n and FN. Chromosome painting with Akodon paranaensis chromosome 21 (a small metacentric akodont marker) paint revealed total homology with the smallest acrocentric Deltamys sp. chromosome, DSP19. This suggests the occurrence of a pericentric inversion or centromeric shift when compared to other akodontines, with a posterior tandem rearrangement giving rise to DKE4. In DKE, large blocks of pericentromeric constitutive heterochromatin are present on the autosomes and the X, and the Y/autosome has an entirely heterochromatic short arm. In DSP, small heterochromatic blocks are observed on autosomes and X, and the Y is a very small, mostly heterochromatic acrocentric. The cytogenetic analyses suggest that the Deltamys sp. karyotype is ancestral, with the derived condition resulting from a tandem fusion (DSP7 + DSP19) and the Y/autosome translocation giving rise to the multiple sex chromosome system. The autosomal rearrangements, the differences in CBG-banding patterns and Ag-NOR localization, as well as the presence of X(1)X(1)X(2)X(2)/X(1)X(2)Y and XX/XY sex determination mechanisms, possibly acting as a reproductive barrier, and the phylogenetic position within the Deltamys genus, with high genetic divergence, call for a taxonomic review of the genus., (Copyright © 2011 S. Karger AG, Basel.)

Social, ecological, and historical processes affect the genetic structure of primate populations, and therefore have key implications for the conservation of endangered species. The northern muriqui (Brachyteles hypoxanthus) is a critically endangered New World monkey and a flagship species for the conservation of the Atlantic Forest hotspot. Yet, like other neotropical primates, little is known about its population history and the genetic structure of remnant populations. We analyzed the mitochondrial DNA control region of 152 northern muriquis, or 17.6% of the 864 northern muriquis from 8 of the 12 known extant populations and found no evidence of phylogeographic partitions or past population shrinkage/expansion. Bayesian and classic analyses show that this finding may be attributed to the joint contribution of female-biased dispersal, demographic stability, and a relatively large historic population size. Past population stability is consistent with a central Atlantic Forest Pleistocene refuge. In addition, the best scenario supported by an Approximate Bayesian Computation analysis, significant fixation indices (Φ(ST) = 0.49, Φ(CT) = 0.24), and population-specific haplotypes, coupled with the extirpation of intermediate populations, are indicative of a recent geographic structuring of genetic diversity during the Holocene. Genetic diversity is higher in populations living in larger areas (>2,000 hectares), but it is remarkably low in the species overall (θ = 0.018). Three populations occurring in protected reserves and one fragmented population inhabiting private lands harbor 22 out of 23 haplotypes, most of which are population-exclusive, and therefore represent patchy repositories of the species' genetic diversity. We suggest that these populations be treated as discrete units for conservation management purposes.

Akodon cursor occurs in dense rainforest from northern (8° S) to southern (26° S) states along the Atlantic coast of Brazil. Previous karyological and molecular data revealed two major clades, one including northern (8-15° S) and the other southern (19-26° S) populations. The center of geographic distribution (15-20° S), which included the state of Espírito Santo, was identified as a potential vicariance region. Since river barriers are among the most discussed models in the study of Neotropical diversification, we examined whether the Rio Doce (19° S) plays an important role in shaping the population genetic divergence of A. cursor by including samples from Espírito Santo in the analysis. Our results showed that the northern-southern division region in Atlantic forest was no coincidence with the presence of the Rio Doce by refuting the hypothesis that this river is an effective barrier to gene flow between populations. Instead, we found evidence that isolation by geographical distance shaped the phylogeographical structure in the southern lineage. However, there is uncertainty about effectiveness of the processes involved and further studies based on wider sampling are needed.

The three-toed sloths (Bradypus) are slow-moving arboreal neotropical mammals. Understanding demographic variables (such as sex ratio) of populations is a key for conservation purposes. Nevertheless, gender assignment of Bradypus is particularly challenging because of the lack of sexual dimorphism in infants and in adults, particularly B. torquatus, the most endangered of the three-toed sloths, in which sex is attributed by visual observation of the reproductively active males. Here, we standardized a method for sexing Bradypus individuals using PCR-RFLP of sex-linked genes ZFX/ZFY. This assay was validated with known-gender animals and proved accurate to assign gender on three Bradypus species., (© 2009 Blackwell Publishing Ltd.)

Juliomys is a small rodent from the family Cricetidae which inhabits the Atlantic forest and forests from Argentina to eastern Brazil. The three species recognized so far have different karyotypes. In this paper, we describe a new karyotype with 2n = 32, FN = 48 found in Juliomys specimens from a high-altitude area in the Atlantic forest of southern Brazil. The karyotype was analyzed after G- and C-banding and silver staining of the nucleolus organizer regions (Ag-NOR) and its G-banding patterns were compared with those of the newly described species Juliomys ossitenuis (2n = 20, FN = 36). The 2n = 32 karyomorph presented peculiar features and was very different from those of the other species of the genus: J. pictipes (2n = 36, FN = 34), J. rimofrons (2n = 20, FN = 34) and J. ossitenuis (2n = 20, FN = 36). Differences were mostly due to centric and tandem fusions, pericentric inversion and loss of heterochromatin. The karyotype represents a powerful tool to differentiate Juliomys species and our data suggest that the karyotype described herein belongs to a new species.

Background: The thin-spined porcupine, also known as the bristle-spined rat, Chaetomys subspinosus (Olfers, 1818), the only member of its genus, figures among Brazilian endangered species. In addition to being threatened, it is poorly known, and even its taxonomic status at the family level has long been controversial. The genus Chaetomys was originally regarded as a porcupine in the family Erethizontidae, but some authors classified it as a spiny-rat in the family Echimyidae. Although the dispute seems to be settled in favor of the erethizontid advocates, further discussion of its affinities should be based on a phylogenetic framework. In the present study, we used nucleotide-sequence data from the complete mitochondrial cytochrome b gene and karyotypic information to address this issue. Our molecular analyses included one individual of Chaetomys subspinosus from the state of Bahia in northeastern Brazil, and other hystricognaths., Results: All topologies recovered in our molecular phylogenetic analyses strongly supported Chaetomys subspinosus as a sister clade of the erethizontids. Cytogenetically, Chaetomys subspinosus showed 2n = 52 and FN = 76. Although the sexual pair could not be identified, we assumed that the X chromosome is biarmed. The karyotype included 13 large to medium metacentric and submetacentric chromosome pairs, one small subtelocentric pair, and 12 small acrocentric pairs. The subtelocentric pair 14 had a terminal secondary constriction in the short arm, corresponding to the nucleolar organizer region (Ag-NOR), similar to the erethizontid Sphiggurus villosus, 2n = 42 and FN = 76, and different from the echimyids, in which the secondary constriction is interstitial., Conclusion: Both molecular phylogenies and karyotypical evidence indicated that Chaetomys is closely related to the Erethizontidae rather than to the Echimyidae, although in a basal position relative to the rest of the Erethizontidae. The high levels of molecular and morphological divergence suggest that Chaetomys belongs to an early radiation of the Erethizontidae that may have occurred in the Early Miocene, and should be assigned to its own subfamily, the Chaetomyinae.

The identification of new bovine male-specific DNA sequences is of great interest because the bovine Y chromosome remains poorly characterized in terms of physical and genetic maps. Since taurine and zebu Y chromosomes are structurally different, the identification of Y-specific sequences present in both sub-species is particularly important: these sequences are of evolutionary significance and can be broadly used for embryo sexing. In this work, we initially used the random amplified polymorphic DNA (RAPD) technique to search for male-specific sequences present as monomorphic markers in genomic DNA from zebu and taurine bulls. A male-specific RAPD band was found to be present and highly conserved in both sub-species, as demonstrated by Southern blotting, fluorescent in situ hybridization (FISH) and DNA sequencing. In a previous work, a pair of primers derived from this marker was successfully used in taurine and zebu embryo sexing.

Comparative studies among four species--Akodonazarae (2n = 38), A. lindberghi (2n = 42), A. paranaensis (2n = 44) and A. serrensis (2n = 46)--employing classic cytogenetics (C- and G-bands) and fluorescence in situ hybridization with telomeric (TTAGGG)n sequencesare reported here. Non-telomeric signals in addition to the regular telomeric sites were detected in three species:A. azarae, A. lindberghi and A. serrensis. One interstitial telomeric site (ITS) was observed proximally at the long arm of chromosome 1 of A. azarae. The comparison of G-banding patterns among the species indicated that the ITS was due to a tandem fusion/fission rearrangement. Non-telomeric signals of A. lindberghi and A. serrensis were not related to chromosomal rearrangements; instead, the sequences co-localized with (i) heterochromatic regions of all chromosomes in A. serrensis; (ii) some heterochromatic regions in A. lindberghi, and (iii) both euchromatic and heterochromatic regions in the metacentric pair of A. lindberghi. These exceptional findings revealed that ITS in Akodon can be related to chromosomal rearrangements and repetitive sequences in the constitutive heterochromatin and that the richness of TTAGGG-like sequences in the euchromatin could be hypothesized to be a result of amplification of the referred sequence along the chromosome arms., (Copyright 2006 S. Karger AG, Basel.)

Established cell lines have long been used for in vitro studies of tumor biology, enabling investigators to control growth conditions and to draw important conclusions about the oncogenic microenvironment. However, gene expression behavior in cultured cells may not always reflect the actual in vivo scenario, and analysis derived from such experiments should take into consideration the existing differences between the two environments. We used suppression subtractive hybridization to study transcriptional changes elicited after oncogene transformation and cell line establishment. We found that transcriptional changes elicited in cultured cell lines are in fact representative of late events, and they do not occur early after oncogene transfection or activation. We also determined that a fraction of the transcriptional changes is oncogene specific, whereas other changes are shared between two or more different oncogenes.

In this article we review the existing cytogenetic information on the polymorphic dot-like chromosomes in Trinomys iheringi, the only species in the family Echimyidae harboring them, and provide new data on the frequency, banding properties, meiotic behavior and DNA composition of these minute chromosomes. Since no individuals lacking these chromosomes have hitherto been found, one of the main properties of B chromosomes, i.e. dispensability, has not yet been tested, so that some reasonable doubt might exist on whether they are true B chromosomes. The dot-like chromosomes were also present in the twelve new individuals analyzed, showed intraindividual variation in number, most likely due to mitotic instability during development, failed to show C-bands, showed late-replication, paired among them in meiosis, but not with the large chromosomes, and appeared to be mainly composed of telomeric DNA. These results suggest that these dot-like chromosomes might actually be mitotically unstable micro B chromosomes showing very high frequency in the natural populations thus far analyzed. But, to be confident of this conclusion, individuals lacking the dot-like chromosomes should actively be searched in future research to test their dispensability., (Copyright 2004 S. Karger AG, Basel)

The karyotypes of the bat species Molossus ater, M. molossus (2n = 48; NF = 64) and Molossops planirostris (2n = 34; NF = 60) were analyzed by G-, C-banding, silver nitrate staining (AgNO3), base-specific fluorochromes and fluorescent in situ hybridization (FISH). The two species of Molossus presented the constitutive heterochromatin (CH) in the pericentromeric regions of all autosomes and in the X chromosome, while the Y chromosome was completely heterochromatic. Molossops planirostris showed conspicuous CH blocks in the pericentromeric regions of the pairs 4, 5, 8, 15, 16 and in the short arm of the X chromosome, while the Y did not present any CH block. Pretreated slides for C-banding stained with DAPI (CB-DAPI) revealed a similar pattern of C-banding (CBG) for these species. Sequential staining (AgNO3/CMA3/DAPI) in M. planirostris showed that the nucleolus organizer regions (NORs) are weakly CMA3 positive and DAPI negative. In the three species, triple staining with CMA3/DA/DAPI revealed R-banding with CMA3 and uniform staining with DAPI. The ribosomal cistrons detected by FISH were present only in the pair 5 in both species of Molossus, and in two pairs of medium sized chromosomes (pairs 9 and 10) of Molossops planirostris. The results obtained by FISH, compared with those by AgNO3 staining, indicated that all NORs in these species are transcriptionally active.

We analyzed the nucleolus organizer regions (NORs) of thirteen bats from genera Phyllostomus, Phylloderma, Trachops, Tonatia, Sturnira, Platyrrhinus, Artibeus and Glossophaga. We used silver staining and FISH with rDNA probe. Nine species had only one Ag-NOR-bearing chromosome pair. Artibeus lituratus, A. jamaicensis and A. fimbriatus presented multiple Ag-NORs located in the short arms of pairs 5, 6 and 7, and an additional mark in the long arm of one chromosome 5 in A. fimbriatus. Artibeus cinereus showed Ag-NORs in the chromosome pairs 10 and 13. The chromosomal location of rRNA genes using FISH agreed with the number and position of NORs in all but one species. In A. cinereus the hybridization signals were seen in three chromosome pairs 9, 10 and 13. This suggests the occurrence of silent NORs in pair 9. Differences in the size and intensity of the hybridization signals were also observed in the pair 9 of A. cinereus.

This paper provides new data on chromosomes of Brazilian vampire bats Desmodus rotundus and Diphylla ecaudata. These species were analyzed by GTG, CBG- and CB-DAPI banding, AgNO3/CMA3 sequential staining, base-specific fluorochrome dyes and in situ hybridization with 18S rDNA probe. C-banding (CBG) revealed constitutive heterochromatin in the pericentromeric regions in all autosomes and the X and Y chromosomes appeared entirely heterochromatic in both species. CB-DAPI revealed a coincident banding pattern to that obtained by CBG. Triple staining CMA3/DA/DAPI revealed an R-banding and a weak G-banding pattern in the karyotypes. Sequential AgNO3/CMA3 staining showed a NOR located interstitially on the long arm of pair 8 in D. rotundus and on the short arm of pair 13 in D. ecaudata. FISH with a rDNA probe confirmed the location and number of NORs; a difference neither in intensity nor in size of hybridization signal was detected between homologues for both species.

Ten species of small rodents of genus Calomys are found in South America. Three of these ten species are known to occur in Brazil: C. tener, C. laucha and C. expulsus (= C. callosus expulsus). Almost all Calomys karyotypes are made up of acrocentric pairs. In this paper we describe a new karyotype with 2n = 46 (FN = 66), including 11 meta/submetacentric and 11 acrocentric autosomal pairs. This is not related to any described Calomys karyotype. The X chromosome is a medium submetacentric and the Y is a small acrocentric. This new karyotype is briefly compared to karyotype of the sympatric species C. tener (2n = 66, FN = 66). The reduced diploid number and small amount of pericentromeric heterochromatin observed in the biarmed chromosomes that contrasts to large blocks seen in acrocentrics seem to indicate that centric fusion and loss of constitutive heterochromatin have led to the new karyotype. Cytogenetic evidence suggests strongly that a new species with 2n = 46 from Central Brazil should be described in the genus Calomys.

In a Brazilian population of the neotropical rodent Akodon montensis we found five sex-reversed XY females. These animals were cytogenetically analyzed by chromosome painting using species-specific DNA probes from the Y chromosome, generated by chromosomal microdissection and subsequent use of the degenerate oligonucleotide-primed polymerase chain reaction (DOP-PCR). The results showed a chromosome complement with an apparently normal Y chromosome and an X chromosome carrying a translocation that encompasses a large portion of the Y chromosome (seemingly the entire Y). Ovarian histology suggested that these females are fertile. Amplification of the SRY HMG box sequence by PCR shows that at least one copy of the Sry gene is present in the A. montensis XY females. Based on our findings, we suggest that the breakpoint of the X;Y translocation probably altered an X-linked sex-determining locus (or loci), blocking testicular organogenesis in the XY females. Further studies are necessary to determine the precise location and role of this putative sex-determining chromosomal region. Genetic mechanisms of XY sex reversal in A. montensis populations are discussed., (Copyright 2000 S. Karger AG, Basel)

The effect of aging on the physiologic responses of renal plasma flow (RPF) and glomerular filtration rate to an acute oral protein load (renal reserve) is a poorly understood process. In this study of 37 healthy human volunteers, distributed among three groups (group 1: n = 13, age range 20-39 years; group 2: n = 13, age range 40-59 years; group 3: n = 11, age range 60-68 years), we evaluated the influence of age on some of the vasoactive systems such as plasma renin activity, urinary kallikrein, plasmatic prokallikrein, plasmatic kallikrein, and plasmatic kininogen on RPF and creatinine clearance (Ccr) in response to an acute oral protein load (1 g/kg body weight). The aging process diminished but did not cease the increments in RPF (group 1: 539.6 vs. 658.9 ml/min/1.73 m(2), p < 0. 001; group 2: 509.0 vs. 570.7 ml/min/ 1.73 m(2), p < 0.001; group 3: 453.9 vs. 506.0 ml/min/ 1.73 m(2), p < 0.001) and Ccr (group 1: 139. 7 vs. 166.5 ml/ min/1.73 m(2), p < 0.001; group 2: 126.6 vs. 142.2 ml/min/1.73 m(2), p < 0.001; group 3: 112.6 vs. 121.4 ml/min/ 1.73 m(2), p < 0.01) after a protein overload. The plasma renin activity did not change after a meat meal. On the other hand, all parameters regarding the kinin system changed significantly in the direction of increased bradykinin formation, despite aging (urinary kallikrein - group 1: 0.25 vs. 0.44 mU/ml, p < 0.005; group 2: 0.25 vs. 0.41 mU/ml, p < 0.005; group 3: 0.33 vs. 0.47 mU/ml, p < 0.005/plasmatic kininogen - group 1: 1.3 vs. 0.9 microg LBK/ml, p < 0.005; group 2: 1.1 vs. 0.7 microg LBK/ml, p < 0.005; group 3: 0.8 vs. 0.7 microg LBK/ml, p < 0.005). These findings indicate that: (1) the aging process narrows but does not cease the increment range in Ccr and RPF after acute oral protein ingestion; (2) increased bradykinin formation plays a definite role in the acute renal vasodilatory response, and (3) contrary to previous clinical studies, our results suggest that the renal reserve is progressively and significantly reduced during the aging process., (Copyright 1999 S. Karger AG, Basel)

We have identified the almost complete correspondence of whole chromosome arms between the karyotypes of Bolomys lasiurus (2n = 33, 34) and Akodon montensis (2n = 24, 25) using comparative analysis of the GTG-banding patterns. To explain the karyotypic differentiation of the species, tandem and centric fusions, pericentric inversions, loss of telomeres and centromeres are required. Localization of telomere sequences using an (TTAGGG)n oligomere as a fluorescence in situ hybridization probe provided evidence of the maintenance of interstitial telomere sequences in a polymorphic centric fusion of recent origin in Bolomys lasiurus. The homeologies shared between the chromosomes of these two species and those of A. cursor (2n = 16), from previous work, are discussed.

All available published cytogenetic data show the presence of 28 different karyotypes in 311 specimens of A. cursor as an exceptional example of high karyotype variability in a single species. Our present sample of 116 animals collected in the rain forest of the Atlantic coast of the states of São Paulo and Bahia, Brazil, show 25 karyotype constitutions. The diploid number (2n) ranged from 16 to 14, and the number of autosomal arms (NF) from 26 to 18, because of centric fusion and pericentric inversions involving two autosome pairs, pericentric inversions in three other chromosome pairs, trisomy in the pair 7 and the presence of two XO females. Synaptonemal complex analysis, associated with data from experimental cross-breeding, suggested that heterozygous individuals for pericentric inversions have normal fertility. In this paper, we have reviewed the chromosomal data of this species, and have thus standardized the karyotype description and chromosome numbering. We discuss about karyotype evolution of Akodon cursor based on the frequency and constitution of karyotypes of all different geographical samples described so far in the literature.

Akodon cursor is an exceptional example of high chromosomal variability, displaying diploid numbers from 14 to 16 and fundamental numbers (FN) from 18 to 26 as the result of a complex rearrangement in par 1 and pericentric inversions in three autosomal pairs. The difference in the diploid number is due to the presence of a large metacentric pair 1 in the 2n=14 karyotype, a large metacentric 1 and two different submetacentrics (1a and 1b) in 2n=15 and 1a and 1b submetacentric pairs in homozygosis in the 2n = 16 karyotype. Chromosomes 1a and 1b share homology with the short and long arms of the large metacentric 1 respectively. In this paper, evidence based on fluorescence in situ hybridization (FISH) with telomeric sequences and G-banding indicates that pericentric inversions and fusion of chromosomes 1a and 1b are the probable rearrangements giving rise to the large metacentric 1.

In this cross-over, double-blind study, 12 essential hypertensive patients (stage I, II, and III) with glomerular filtration rate (GFR) between 50 to 80 mL/min/1.73 m2, were submitted to 4 weeks of placebo followed by 12 weeks with isradipine SRO (IS) 5 mg, spirapril (SP) 6 mg, and isradipine plus spirapril (IS + SP). The study evaluated the effects of these drugs on GFR ((99m)Tc DTPA), effective renal plasma flow (ERPF) ((131)I-orthoiodohippurate), urinary sodium excretion (UNaV), urinary kallikrein excretion (UKal), urinary albumin excretion (UAE), and plasma renin activity (PRA). The three protocols significantly reduced mean blood pressure (128 v 107 mm Hg; 126 v 112 mm Hg; 129 v 104 mm Hg with IS, SP and IS + SP, respectively). ERPF and GFR did not change. UNaV increased significantly after IS (0.17 v 0.22 mEq/min) and IS + SP (0.18 v 0.24 mEq/min). UKal increased significantly after IS (58.6%) and IS + SP (53.6%). UAE decreased significantly only after SP. PRA increased significantly after IS (1.31 v 2.84 ng/mL/h), SP (1.10 v 2.15 ng/mL/h), and after IS + SP (1.23 v 3.21 ng/mL/min). In conclusion, IS, SP and IS + SP were effective in reducing blood pressure while keeping renal function stable. Only SP significantly decreased UAE. Enhanced UKal may have played a role in natriuresis observed after IS and IS + SP.

The neotropical rodents Akodon cursor (2n = 14, 15, and 16) and A. montensis (2n = 24 and 25), two closely related and morphologically indistinguishable species, have been compared by G-banding and chromosome painting. In situ hybridization of a biotinylated DOP-PCR product obtained from a microdissected chromosome of A. cursor onto A. montensis chromosomes was performed in combination with localization of telomeric sequences using a (TTAGGG)n oligomer as a FISH probe. The results provide evidence of the complex chromosomal rearrangements suggested by GTG-banding analysis, indicating the origin of one A. cursor autosome from three different A. montensis autosomes. Furthermore, the complete cytogenetic homeology between the A. cursor and A. montensis karyotypes was determined, along with the occurrence of tandem fusions and pericentric inversions and the loss of telomeres, centromeres, and chromosome arms. Evidence for the ancestral origin of the A. cursor karyotype is also provided.

Fifteen patients with uncomplicated mild to moderate primary hypertension (7 males, 8 females, age range 36-65 years) were submitted to a double blind randomized crossover study, receiving MgO 3 times a day at a daily dose of 1.0 g (600 mg/day of magnesium) and placebo for a period of 6 weeks. This was to test the effects of oral magnesium supplementation on blood pressure and sodium, potassium, calcium and magnesium intraerythrocyte concentrations. Concomitantly, plasma renin activity and serum aldosterone was also measured. Oral magnesium reduced significantly the systolic (delta = -7.6 mmHg, P < 0.05); diastolic (delta = -3.8 mmHg, P < 0.01) and mean blood pressure (delta = -5.9 mmHg, P < 0.01). After magnesium supplementation intraerythrocyte sodium concentration was reduced (delta = -0.55 mEq/l per cell, P < 0.01) and intraerythrocyte magnesium concentration was increased (delta = 1.20 mg/dl per cell, P < 0.01). The diminution of the blood pressure correlated positively with the reduction in intraerythrocyte sodium (r = 0.66, P < 0.01) after magnesium. However, our results have shown that the blood pressure response to oral magnesium was not homogeneous. Forty percent of our patients had their blood pressure effectively controlled (more than 10 mmHg reduction in mean blood pressure), being the hypotensive effect more evident in patients with recent hypertension and in those where the reduction in intraerythrocyte sodium was significantly greater than in the non-responder individuals. Intraerythrocyte potassium and calcium, serum aldosterone, plasma renin activity and urinary sodium excretion were maintained unchanged after magnesium supplementation. These data showed that oral magnesium supplementation may reduce the blood pressure, which can be partially explained by the decrease in intracellular sodium and augment in intracellular magnesium.

Purpose: To evaluate the effects of urapidil on blood pressure (BP), renal hemodynamics and lipid and glucose metabolism, in patients with mild-to-moderate uncomplicated essential hypertension., Methods: Fifteen hypertensive patients, aged 38-64 year-old were studied by ambulatory blood pressure monitoring system (ABPM). It was also evaluated: 1) the creatinine clearance; 2) the effective renal plasma flow by use of a single plasma sample after injection of orthoiodohippurate; 3) the serum triglycerides, cholesterol, and HDL-cholesterol; 4) blood levels of glucose and insulin. The urapidil dose ranged from 60 to 180 mg/day, according to the individual response., Results: The values after four weeks washout-placebo and active treatment with urapidil showed: the systolic/diastolic BP was reduced from 157.7 +/- 6/108.0 +/- 2 on placebo to 140.4 +/- 4/97.3 +/- 3 mmHg (p < 0.05/p < 0.01) after urapidil, respectively, whereas heart rate was unchanged. The percentage of elevated systolic and diastolic BP values during 24h (BP load) was reduced from 60.9% to 54.4% and from 60.8% to 50.3%, respectively. Effective renal plasma flow, glomerular filtration rate, filtration fraction and renal vascular resistance were unaltered by treatment. Significant increase in HDL-cholesterol was observed (from 39.5 +/- 3.6 on placebo vs 49.2 +/- 4.8 mg/dl (p < 0.01) after urapidil. Total cholesterol, LDL-cholesterol and triglycerides levels were not modified with treatment. Circulating plasma glucose and insulin remained unchanged., Conclusion: Urapidil is an effective antihypertensive agent without deleterious effect on renal hemodynamics, lipid and glucose metabolism.

Most studies that have attempted to distinguish pregnancy-induced hypertension from chronic hypertension in pregnancy include arbitrary clinical definitions and morphological reports based on renal biopsy. To evaluate whether these conditions have different responses to stimuli to the renin-angiotensin-aldosterone system, we studied four normal nonpregnant women, eight normal pregnant women, 10 women with pregnancy-induced hypertension, and 14 with chronic hypertension in pregnancy, in the third trimester of pregnancy, after they had sequentially adopted the supine, the left lateral recumbent, and the orthostatic positions for 90 minutes each. Postural maneuvers did not significantly change mean arterial pressure in pregnancy-induced hypertensive or in normal pregnant women, although in chronic hypertensive women, a significant reduction in this parameter was observed in left lateral recumbency. The renin-angiotensin-aldosterone system was significantly less activated with women in the supine position in pregnancy-induced hypertensive and chronic hypertensive women; however, as opposed to pregnancy-induced hypertensive women, those with chronic hypertension reassumed their humoral response to upright posture, which was accompanied by a significant reduction in sodium excretion. The parallelism between plasma renin activity and aldosterone levels, absent in normal pregnancy, returned in pregnancy-induced hypertensive and chronic hypertensive women in the erect posture (r = 0.73, p less than 0.01; r = 0.68, p less than 0.01, respectively). These data suggest that the adoption of the left lateral recumbent position in pregnancy reduces mean arterial pressure only in chronic hypertensive women. Moreover, in chronic hypertension, the upright position provoked a significant response of the renin-angiotensin-aldosterone system. This effect was not observed in women with pregnancy-induced hypertension.

The objective of this double-blind, placebo-controlled study was to evaluate the effects of isradipine on renal hemodynamics and function. Ten patients with mild-to-moderate hypertension were given isradipine at 2.5 mg twice daily for 3 months after 4 weeks of placebo washout. Renal studies were performed 2 h after the morning administration of treatment. The results of these evaluations indicate that isradipine as monotherapy significantly reduced the mean arterial pressure, while the effective renal plasma flow was increased (+16%) and glomerular filtration rate remained virtually unchanged (-8.7 ml/min). The filtration fraction and renal vascular resistance decreased significantly. There was a significant decrease in the absolute rate of proximal sodium reabsorption, and a significant increase in the distal reabsorption. Clearance of sodium remained unchanged. In conclusion, monotherapy with low-dose isradipine was not only effective in controlling blood pressure, but also decreased the renal vascular resistance while avoiding glomerular hyperfiltration, and exerted a protective effect on renal hemodynamics. Natriuresis also remained stable despite the blood pressure reduction.