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1.
Genet Mol Biol ; 43(4): e20200195, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33156892

RESUMO

The Cyprinidae family is a highly diversified but demonstrably monophyletic lineage of cypriniform fishes. Among them, the genus Osteochilus contains 35 recognized valid species distributed from India, throughout Myanmar, Laos, Thailand, Malaysia, Indonesian archipelago to southern China. In this study, karyotypes and other chromosomal characteristics of five Osteochilus species occurring in Thailand, namely O. lini, O. melanopleura, O. microcephalus, O. vittatus and O. waandersii were examined using conventional and molecular cytogenetic protocols. Our results showed they possessed diploid chromosome number (2n) invariably 2n = 50, but the ratio of uni- and bi-armed chromosomes was highly variable among their karyotypes, indicating extensive chromosomal rearrangements. Only one chromosome pair bearing 5S rDNA sites occurred in most species, except O. melanopleura, where two sites were detected. In contrast, only one chromosomal pair bearing 18S rDNA sites were observed among their karyotypes, but in different positions. These cytogenetic patterns indicated that the cytogenomic divergence patterns of these Osteochilus species were largely corresponding to the inferred phylogenetic tree. Similarly, different patterns of the distributions of rDNAs and microsatellites across genomes of examined species as well as their different karyotype structures indicated significant evolutionary differentiation of Osteochilus genomes.

2.
Genes (Basel) ; 11(10)2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33050411

RESUMO

The armored Harttia catfishes present great species diversity and remarkable cytogenetic variation, including different sex chromosome systems. Here we analyzed three new species, H. duriventris, H. villasboas and H. rondoni, using both conventional and molecular cytogenetic techniques (Giemsa-staining and C-banding), including the mapping of repetitive DNAs using fluorescence in situ hybridization (FISH) and comparative genomic hybridization (CGH) experiments. Both H. duriventris and H. villasboas have 2n = ♀56/♂55 chromosomes, and an X1X1X2X2 /X1X2Y sex chromosome system, while a proto or neo-XY system is proposed for H. rondoni (2n = 54♀♂). Single motifs of 5S and 18S rDNA occur in all three species, with the latter being also mapped in the sex chromosomes. The results confirm the general evolutionary trend that has been noticed for the genus: an extensive variation on their chromosome number, single sites of rDNA sequences and the occurrence of multiple sex chromosomes. Comparative genomic analyses with another congeneric species, H. punctata, reveal that the X1X2Y sex chromosomes of these species share the genomic contents, indicating a probable common origin. The remarkable karyotypic variation, including sex chromosomes systems, makes Harttia a suitable model for evolutionary studies focusing on karyotype differentiation and sex chromosome evolution among lower vertebrates.

3.
Int J Mol Sci ; 21(7)2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32283616

RESUMO

Freshwater prawns of the genus Macrobrachium are one of the important components of circumtropical marine, estuarine, and freshwater environments. They have been extensively exploited for human consumption for many years. More than 250 species reflect the evolutionary success of this highly diversified group, with a complex and challenging taxonomy due to morphological variations and vast geographical distribution. Although genetic approaches have been used to clarify phylogenetic and taxonomic aspects of Macrobrachium species, cytogenetic information is still very scarce and mostly focused on chromosome number and morphology. Here, we present chromosome data for three species from the Neotropical region, M. carcinus, M. acanthurus, and M. amazonicum, and one species from the Oriental region, M. rosenbergii. Using conventional cytogenetic approaches and chromosome mapping of repetitive DNAs by fluorescence in situ hybridization (FISH), we identified numerical diversification of the diploid set, within and between both zoogeographic regions. These included M. acanthurus and M. amazonicum sharing diploid chromosomes of 98, while M. carcinus has 94, and M. rosenbergii has 118 chromosomes. Argentophilic sites are also variable in number, but they occur in a much higher number than 18S rDNA, representing two to 10 sites within the study species. Microsatellites repeat motifs are also abundant in the chromosomes, with a co-localization and uniform distribution along the chromosome arms, but completely absent in the AT-rich centromeric regions. As a whole, our study suggests that the 2n divergence was followed by a considerable rDNA diversification. The abundance of the exceptional amount of microsatellite sequences in the chromosomes also suggests that they are essential components of the Macrobrachium genome and, therefore, maintained as a shared feature by the species, the reason for which is yet unknown.

4.
Genes (Basel) ; 11(4)2020 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-32231057

RESUMO

Lebiasinidae fishes have been historically neglected by cytogenetical studies. Here we present a genomic comparison in eleven Lebiasinidae species, in addition to a review of the ribosomal DNA sequences distribution in this family. With that, we develop ten sets of experiments in order to hybridize the genomic DNA of representative species from the genus Copeina, Copella, Nannostomus, and Pyrrhulina in metaphase plates of Lebiasina melanoguttata. Two major pathways on the chromosomal evolution of these species can be recognized: (i) conservation of 2n = 36 bi-armed chromosomes in Lebiasininae, as a basal condition, and (ii) high numeric and structural chromosomal rearrangements in Pyrrhulininae, with a notable tendency towards acrocentrization. The ribosomal DNA (rDNA) distribution also revealed a marked differentiation during the chromosomal evolution of Lebiasinidae, since both single and multiple sites, in addition to a wide range of chromosomal locations can be found. With some few exceptions, the terminal position of 18S rDNA appears as a common feature in Lebiasinidae-analyzed species. Altogether with Ctenoluciidae, this pattern can be considered a symplesiomorphism for both families. In addition to the specific repetitive DNA content that characterizes the genome of each particular species, Lebiasina also keeps inter-specific repetitive sequences, thus reinforcing its proposed basal condition in Lebiasinidae.

5.
Ther Adv Gastrointest Endosc ; 12: 2631774519867786, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31489404

RESUMO

Background and aims: Post liver transplant biliary anastomotic strictures have traditionally been treated with balloon dilation and multiple plastic stents. Fully covered self-expandable metallic stents may be used as an initial alternative or after multiple plastic stents failure. Refractory strictures can occur in 10-22% and require revisional surgery. Alternatively, cholangioscopy allows direct visualization and therapeutic approaches. We aimed to assess the feasibility, safety, and efficacy of balloon dilation combined with cholangioscopy-guided steroid injection for the treatment of refractory anastomotic biliary strictures. Methods: Three post-orthotopic liver transplant patients who failed standard treatment of their biliary anastomotic strictures underwent endoscopic retrograde cholangiopancreatography with balloon dilation followed by cholangioscopy-guided steroid injection at a tertiary care center. Patients had follow-up with images and laboratorial tests to evaluate for residual stricture. Results: Technical success of balloon dilation + cholangioscopy-guided steroid injection was achieved in all patients. Cholangioscopy permitted accurate evaluation of bile ducts and precise localization for steroid injection. No adverse events occurred. Mean follow-up was 26 months. Two patients are stent free and remain well in follow-up, with no signs of biliary obstruction. No further therapeutic endoscopic procedures or revisional surgery were required. One patient did not respond to balloon dilation + cholangioscopy-guided steroid injection after 11 months of follow-up and required repeat balloon dilation of new strictures above the anastomosis. Conclusion: Cholangioscopy-guided steroid injection combined with balloon dilation in the treatment of refractory post liver transplant strictures is feasible and safe. This method may be used as a rescue alternative before surgical approach. Randomized controlled trials comparing balloon dilation + cholangioscopy-guided steroid injection to fully covered self-expandable metallic stents are needed to determine the role of this treatment for anastomotic biliary strictures.

6.
Eur J Gastroenterol Hepatol ; 31(9): 1148-1156, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31247632

RESUMO

BACKGROUND: Liver transplantation (LT) is the treatment of choice for patients with unresectable early hepatocellular carcinoma (HCC). Post-LT HCC recurrence rates range from 8 to 20% and still impact on overall survival (OS). The aim of our study was to evaluate the impact of HCC recurrence on post-LT survival and analyze prognostic factors among those patients with recurrence. PATIENTS AND METHODS: We carried out a national, multicenter, retrospective cohort study in Brazil. Medical records of 1119 LT recipients with HCC were collected. Data from patients with post-LT HCC recurrence were analyzed and correlated with post-relapse survival. RESULTS: OS of the 1119 patients included in the study was 63% over 5 years. Post-LT HCC recurrence occurred in 86 (8%) patients. The mean time to recurrence was 12 months. Sites of recurrence were extrahepatic in 55%, hepatic in 27%, and both hepatic and extrahepatic in 18%. Recurrence treatment was performed in 50 (64%) cases, mostly with sorafenib. Post-relapse survival rates were 34% at 1 year and 13% at 5 years. Univariable analysis identified α-fetoprotein more than 1000 ng/ml at relapse, recurrence treatment, extrahepatic location, and time to recurrence more than 2 years as prognostic factors. In multivariable analysis, recurrence treatment, extrahepatic location, and time to recurrence more than 2 years were independent predictors of better survival. CONCLUSION: In a large Brazilian cohort of LT recipients with HCC, post-LT HCC recurrence occurred in 8% and impacted significantly on the OS. Patients with early recurrence presented a worse prognosis. However, treatment of recurrence improved outcomes, highlighting the importance of early diagnosis.

7.
J Travel Med ; 26(5)2019 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-31150098

RESUMO

BACKGROUND: Little is known about clinical characteristics and management of severe yellow fever as previous yellow fever epidemics often occurred in times or areas with little access to intensive care units (ICU). We aim to describe the clinical characteristics of severe yellow fever cases requiring admission to the ICU during the 2018 yellow fever outbreak in São Paulo, Brazil. Furthermore, we report on preliminary lessons learnt regarding clinical management of severe yellow fever. METHODS: Retrospective descriptive cohort study. Demographic data, laboratory test results on admission, clinical follow-up, and clinical outcomes were evaluated. RESULTS: From 10 January to 11 March 2018, 79 patients with laboratory confirmed yellow fever were admitted to the ICU in a tertiary hospital in Sao Paolo because of rapid clinical deterioration. On admission, the median AST was 7,000 IU/L, ALT 3,936 IU/L, total bilirubin 5.3 ml/dL, platelet 74 × 103/mm3, INR 2.24 and factor V 37%. Seizures occurred in 24% of patients, even without substantial intracranial hypertension. The high frequency of pancreatitis and rapidly progressive severe metabolic acidosis were notable findings. 73% of patients required renal replacement therapy. The in-hospital fatality rate was 67%. Patients with diabetes mellitus had a higher case fatality rate (CFR) of 80%, while patients without diabetes had a CFR of 65%. Leading causes of death were severe gastrointestinal bleeding, epileptic status, severe metabolic acidosis, necrohemorrhagic pancreatitis, and multi-organ failure. CONCLUSIONS: Severe yellow fever is associated with a high CFR. The following management lessons were learnt: Anticonvulsant drugs in patients with any symptoms of hepatic encephalopathy or arterial ammonia levels >70 µmol/L was commenced which reduced the frequency of seizures from 28% to 17%. Other new therapy strategies included early institution of plasma exchange. Due to the high frequency of gastric bleeding, therapeutic doses of intravenous proton pump inhibitors should be administered.

8.
Histopathology ; 75(5): 638-648, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31087672

RESUMO

AIMS: The clinical spectrum of yellow fever (YF) ranges from asymptomatic to fulminant hepatitis. During the sylvatic YF epidemic in the metropolitan area of São Paulo, Brazil in 2018, seven orthotopic liver transplantations (OLTs) were performed in our institution to treat fulminant YF hepatitis. Three patients recovered, while four patients died following OLT. The autopsy findings of all these cases are presented herein as the first description of YF in transplanted patients. METHODS AND RESULTS: All patients were men, aged 16-40 years, without vaccination to YF virus (YFV). All organs were examined, with tissue sampling for histopathological analysis. Detection of YF virus antigens (YFV Ag) was performed with two primary antibodies (mouse polyclonal anti-YFV antibody directed to wild strain and a goat anti-YF virus antibody), and RT-PCR assays were utilised to detect YFV-RNA. All the cases depicted typical findings of YF hepatitis in the engrafted liver. The main extrahepatic findings were cerebral oedema, pulmonary haemorrhage, pneumonia, acute tubular necrosis and ischaemic/reperfusion pancreatitis. Of the four cases, the YVF Ag was detected in the heart in one case, liver and testis in three cases, and the kidney and spleen in all four cases. All four cases had YF virus RNA detected by RT-PCR in the liver and in other organs. CONCLUSIONS: Infection of the engrafted liver and other organs by YFV, possibly combined with major ischaemic systemic lesions, may have led to the death of four of the seven patients undergoing OLT.


Assuntos
Transplante de Fígado , Necrose Hepática Massiva/virologia , Transplantes/virologia , Febre Amarela , Vírus da Febre Amarela , Adolescente , Adulto , Autopsia , Brasil , Humanos , Transplante de Fígado/mortalidade , Masculino , Febre Amarela/patologia , Febre Amarela/cirurgia , Febre Amarela/virologia , Adulto Jovem
9.
Cytogenet Genome Res ; 157(4): 239-248, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30991393

RESUMO

Centropomus is the sole genus of the Centropomidae family (Teleostei), comprising 12 species widely distributed throughout the Western Atlantic and Eastern Pacific, with 6 of them occurring in the Western Atlantic in extensive sympatry. Their life history and phylogenetic relationships are well characterized; however, aspects of chromosomal evolution are still unknown. Here, cytogenetic analyses of 2 Centropomus species of great economic value (C. undecimalis and C. mexicanus) were performed using conventional (Giemsa, Ag-NOR, and fluorochrome staining, C- and replication banding) and molecular (chromosomal mapping of 18S and 5S rDNA, H2A-H2B and H3 hisDNA, and (TTAGGG)n repeats) approaches. The karyotypes of both species were composed of 48 solely acrocentric chromosomes (2n = 48; FN = 48), but the single ribosomal site was located in varying positions in the long arms of the second largest chromosome pair. Replication bands were generally similar, although conspicuous differences were observed in some chromosome regions. In both species, the histone H3 genes were located on 3 apparently homeologous chromosome pairs, but the exact position of these clusters differed slightly. Interspecific hisDNA and rDNA site displacements can indicate the occurrence of multiple paracentric inversions during the evolutionary diversification of the Centropomus genomes. Although the karyotypes remained similar in both species, our data demonstrate an unsuspected microstructural reorganization between them, driven most likely by a series of paracentric inversions.


Assuntos
Inversão Cromossômica , Cromossomos/genética , Peixes/genética , Animais , Mapeamento Cromossômico , Evolução Molecular , Peixes/classificação , Hibridização in Situ Fluorescente , Cariótipo , Cariotipagem , Filogenia
10.
Ethn Dis ; 29(Suppl 1): 153-158, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30906164

RESUMO

Health inequities across the Americas are avoidable and unjust yet continue to persist. Systemic social determinants of health, which could be addressed at the policy level, are root causes of many inequities and prevent marginalized individuals and at-risk populations from reaching optimal health and well-being. In this article, we describe our approach to promote health equity through the intersectoral partnerships that were forged, and strategies that were shared, during the convening entitled "Summit 2017: Health Equity in the Americas" and the resulting emergence of the Health Equity Network of the Americas (HENA). We illustrate how this international network will raise awareness of policies and programs to inform decision makers about actions they can take to put an end to the unjust, persistent and mostly avoidable health inequities facing the Americas today.

11.
BMC Evol Biol ; 19(1): 73, 2019 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-30849933

RESUMO

BACKGROUND: Synbranchidae or swamp eels are fishes belonging to the order Synbranchiformes that occur in both freshwater and occasionally in brackish. They are worldwide distributed in tropical and subtropical rivers of four different continents. A large degree of chromosomal variation has been found in this family, mainly through the use of conventional cytogenetic investigations. Inside this group, a still almost unexplored species under the cytogenetic point of view is the Asian swamp eel Monopterus albus, a widely distributed species throughout Asia. Here, we tested the hypothesis of chromosomal speciation, where a case of sympatric speciation may occur as the primary consequence of chromosomal rearrangements. We performed a comparative chromosomal analysis of M. albus from 22 different localities in Thailand, using distinct staining methods (C-banding, Ag-NO3, and Chromomycin A3), and FISH with repetitive DNA probes (5S rDNA, 18S rDNA, Rex1 element and microsatellite repeats). RESULTS: This approach evidenced two contrasting karyotypes (named karyomorphs A and B) that varied concerning their 2n and repetitive DNAs distribution, where chromosomal fusions and pericentric inversions were involved in such differentiation. While the karyomorph A has 2n = 24 chromosomes, the karyomorph B has only 2n = 18, both with NF = 24. In addition, karyomorph A contains only acrocentric chromosomes, while karyomorph B contains three unique metacentric pairs. These features highlight that M. albus has already gone through a significant genomic divergence, and may include at least two cryptic species. CONCLUSIONS: This marked chromosomal differentiation, likely linked to the lifestyle of these fishes, point to the occurrence of a chromosomal speciation scenario, in which fusions and inversions had a prominent role. This highlights the biodiversity of M. albus and justifies its taxonomic revision, since this nominal species may constitute a species complex.


Assuntos
Evolução Biológica , Cromossomos/genética , Especiação Genética , Variação Genética , Cariótipo , Smegmamorpha/genética , Animais , Bandeamento Cromossômico , Mapeamento Cromossômico , Geografia , Metáfase/genética , Repetições de Microssatélites/genética , Tailândia
12.
Eur J Gastroenterol Hepatol ; 30(8): 930-937, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29979644

RESUMO

BACKGROUND: Cirrhotic cardiomyopathy is characterized by an attenuated contractile response to stress. Long-term exposure of ß-adrenergic receptors to persistently high levels of catecholamines has been implicated in its pathogenesis. We hypothesized that ß-blockade with metoprolol could reverse the changes in heart function and morphology in cirrhotic cardiomyopathy. PATIENTS AND METHODS: In this prospective randomized trial, we included 78 patients aged between 18 and 60 years with abnormal cardiac output response under dobutamine stress echocardiography, without primary cardiac disease or a history of alcohol intake. Patients were assigned randomly to receive metoprolol or placebo for 6 months. The primary endpoint was the improvement in cardiac output response to stress, measured by an increase in the left ventricle stroke volume more than 30%. RESULTS: Three (7.3%) patients in the metoprolol group and nine (24.3%) patients in the placebo group showed improved stroke volume (P=0.057). Diastolic dysfunction was found in two (4.8%) patients before and in five (15.6%) patients after therapy in the metoprolol group, and in 10 (27%) patients before and nine (31%) patients after therapy in the placebo group (P=0.67). After treatment, no echocardiography parameter of morphology was significantly different between metoprolol or placebo groups. No significant differences were observed in noradrenaline, plasma renin activity, and troponin levels between groups. Cirrhosis-related clinical events, including hospitalizations and mortality, were not significantly different between the two groups. Six months of therapy with ß-blocker did not ameliorate heart function and morphology in patients with cirrhotic cardiomyopathy.


Assuntos
Antagonistas de Receptores Adrenérgicos beta 1/uso terapêutico , Cardiomiopatias/tratamento farmacológico , Cirrose Hepática/tratamento farmacológico , Metoprolol/uso terapêutico , Adolescente , Antagonistas de Receptores Adrenérgicos beta 1/efeitos adversos , Adulto , Biomarcadores/sangue , Brasil , Débito Cardíaco/efeitos dos fármacos , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/etiologia , Cardiomiopatias/fisiopatologia , Ecocardiografia sob Estresse , Feminino , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico , Masculino , Metoprolol/efeitos adversos , Pessoa de Meia-Idade , Contração Miocárdica/efeitos dos fármacos , Norepinefrina/sangue , Estudos Prospectivos , Recuperação de Função Fisiológica , Renina/sangue , Fatores de Tempo , Resultado do Tratamento , Troponina/sangue , Função Ventricular Esquerda/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos , Adulto Jovem
13.
Planta ; 248(1): 197-209, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29675765

RESUMO

MAIN CONCLUSION: Seeds of native species from the rain forest (Amazon) are source of chitinases and their protein extracts exhibited strong and broad antifungal activity. Numerous plant species native to the Amazon have not yet been chemically studied. Studies of seeds are scarcer, since adversities in accessing study areas and seasonality pose constant hurdles to systematic research. In this study, proteins were extracted from seeds belonging to endemic Amazon species and were investigated for the first time. Proteolytic activity, peptidase inhibitors, and chitinases were identified, but chitinolytic activity predominated. Four proteins were purified through chromatography and identified as lectin and chitinases by MS/MS analyses. The proteins were examined for inhibition of a phytopathogen (Fusarium oxysporum). Analyses by fluorescence microscopy suggested binding of propidium iodide to DNA of fungal spores, revealing that spore integrity was lost when accessed by the proteins. Further structural and functional analyses of defensive proteins belonging to species facing highly complex ecosystems such as Amazonia should be conducted, since these could provide new insights into specificity and synergism involving defense proteins of plants submitted to a very complex ecosystem.


Assuntos
Antifúngicos/isolamento & purificação , Proteínas de Plantas/isolamento & purificação , Sementes/química , Quitinases/isolamento & purificação , Quitinases/farmacologia , Eletroforese em Gel de Poliacrilamida , Fabaceae/química , Fusarium/efeitos dos fármacos , Lectinas/isolamento & purificação , Lectinas/farmacologia , Espectrometria de Massas , Microscopia de Fluorescência , Proteínas de Plantas/farmacologia , Proteômica , Floresta Úmida , Esporos Fúngicos/efeitos dos fármacos
14.
Comp Cytogenet ; 12(2): 145-162, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29675141

RESUMO

Representatives of the order Labriformes show karyotypes of extreme conservatism together with others with high chromosomal diversification. However, the cytological characterization of epigenetic modifications remains unknown for the majority of the species. In the family Labridae, the most abundant fishes on tropical reefs, the genomes of the genus Bodianus Bloch, 1790 have been characterized by the occurrence of a peculiar chromosomal region, here denominated BOD. This region is exceptionally decondensed, heterochromatic, argentophilic, GC-neutral and, in contrast to classical secondary constrictions, shows no signals of hybridization with 18S rDNA probes. In order to characterize the BOD region, the methylation pattern, the distribution of Alu and Tol2 retrotransposons and of 18S and 5S rDNA sites, respectively, were analyzed by Fluorescence In Situ Hybridization (FISH) on metaphase chromosomes of two Bodianus species, B. insularis Gomon & Lubbock, 1980 and B. pulchellus (Poey, 1860). Immunolocalization of the 5-methylcytosine revealed hypermethylated chromosomal regions, dispersed along the entire length of the chromosomes of both species, while the BOD regions exhibited a hypomethylated pattern. Hypomethylation of the BOD region is associated with the precise co-location of Tol2 and Alu elements, suggesting their active participation in the regulatory epigenetic process. This evidence underscores a probable differential methylation action during the cell cycle, as well as the role of Tol2/Alu elements in functional processes of fish genomes.

15.
Front Genet ; 9: 71, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29556249

RESUMO

The Erythrinidae family (Teleostei: Characiformes) is a small Neotropical fish group with a wide distribution throughout South America, where Hoplias malabaricus corresponds to the most widespread and cytogenetically studied taxon. This species possesses significant genetic variation, as well as huge karyotype diversity among populations, as reflected by its seven major karyotype forms (i.e., karyomorphs A-G) identified up to now. Although morphological differences in their bodies are not outstanding, H. malabaricus karyomorphs are easily identified by differences in 2n, morphology and size of chromosomes, as well as by distinct evolutionary steps of sex chromosomes development. Here, we performed comparative genomic hybridization (CGH) to analyse both the intra- and inter-genomic status in terms of repetitive DNA divergence among all but one (E) H. malabaricus karyomorphs. Our results indicated that they have close relationships, but with evolutionary divergences among their genomes, yielding a range of non-overlapping karyomorph-specific signals. Besides, male-specific regions were uncovered on the sex chromosomes, confirming their differential evolutionary trajectories. In conclusion, the hypothesis that H. malabaricus karyomorphs are result of speciation events was strengthened.

16.
HPB (Oxford) ; 20(8): 687-694, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29571616

RESUMO

BACKGROUND: Laparoscopy-assisted (hybrid) liver surgery is considered a minimally invasive technique, however there are doubts regarding loss of the benefits of laparoscopy due to the use of an auxiliary incision. The aim of this study was to compare perioperative results of hybrid vs. open and hybrid vs. pure laparoscopic approach to liver resection for focal lesions and living donation. METHODS: A systematic review was performed in Medline, EMBASE, Cochrane Library Central and LILACS databases. Perioperative outcomes were analyzed. RESULTS: 21 studies were included. Hybrid vs. open: operative time was lower in open group (mean difference [MD] = 34 min; 95%CI: 22-47; P < 0.001; N = 669). Hybrid technique was associated with a reduction in operative blood loss [MD = -43 ml; 95%CI: -74-(-13); P = 0.005, N = 1738]; shorter hospital stay [MD = -1.9 days; 95%CI: -3.2-(-0.5); P = 0.008; N = 833] and lower morbidity [risk difference (RD) = -0.05; 95%CI: -0.10-(-0.01); P = 0.010; N = 1359]. Hybrid vs. pure laparoscopic: There was no difference regarding blood loss, transfusion rate, hospital stay and morbimortality. DISCUSSION: Hybrid technique had perioperative outcomes that were more in keeping with pure laparoscopic outcomes than open surgery. Hybrid liver surgery should be considered a minimally invasive approach.


Assuntos
Hepatectomia/métodos , Laparoscopia/métodos , Transplante de Fígado/métodos , Doadores Vivos , Hepatectomia/efeitos adversos , Hepatectomia/mortalidade , Humanos , Laparoscopia/efeitos adversos , Laparoscopia/mortalidade , Transplante de Fígado/efeitos adversos , Transplante de Fígado/mortalidade , Complicações Pós-Operatórias/etiologia , Medição de Risco , Fatores de Risco , Resultado do Tratamento
17.
Cytogenet Genome Res ; 153(2): 96-104, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29186711

RESUMO

The genus Colomesus is the sole representative of the family Tetraodontidae in the Amazon region. Here, Colomesus asellus was analyzed using conventional and molecular cytogenetic protocols. Its diploid chromosome number is 2n = 46 with 12 meta-, 10 submeta-, 16 subtelo-, and 8 acrocentric chromosomes and a fundamental number of FN = 84. An XX/XY sex chromosome system was identified. Mapping of 18S rDNA correlated with the nucleolus organizer regions (Ag-NORs) in the short arms of the 2 X chromosomes in females and in the Y chromosome in males. C-banding revealed heterochromatin in the centromeric regions of all chromosomes, except for pair 3. Prominent sex chromosome-specific heterochromatin amplification was observed, covering the short arms of the Y chromosome almost entirely. FISH with telomeric and tropomyosin (tpm1) sequences, respectively, revealed terminal signals in all chromosomes. The analysis of extended DNA fibers confirmed the colocalization and the interspersed pattern of the telomeric and tpm1 sequences. Thus, this study highlights the remarkable evolutionary dynamism presented by the Amazonian puffer fish regarding the differentiation of a heteromorphic XY sex chromosome system and a particular sex-specific amplification of rDNA sites. This is the first record of such an association in the Tetraodontidae family.


Assuntos
Cromossomos Sexuais/genética , Processos de Determinação Sexual , Tetraodontiformes/genética , Animais , Antígenos Nucleares/genética , Brasil , Bandeamento Cromossômico , DNA Ribossômico/genética , Feminino , Amplificação de Genes , Hibridização in Situ Fluorescente , Masculino , RNA Ribossômico 18S/genética , Sequências Repetitivas de Ácido Nucleico , Telômero/genética , Telômero/ultraestrutura , Tropomiosina/genética
18.
Front Genet ; 8: 120, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28983316

RESUMO

Bunocephalus is the most species-rich Aspredinidae genus, corresponding to a monophyletic clade with 13 valid species. However, many species have their classification put in question. Here, we analyzed individuals from four Amazonian populations of Bunocephalus coracoideus by cytogenetic and molecular procedures. The geographic distribution, genetic distances and karyotype data indicate that each population represents an Evolutionary Significant Unit (ESU). Cytogenetic markers showed distinct 2n and karyotype formulas, as well as different numbers and locations of the rDNA sites among ESUs. One of such populations (ESU-D) highlighted an extensive polymorphic condition, with several cytotypes probably due to chromosomal rearrangements and meiotic non-disjunctions. This resulted in several aneuploid karyotypes, which was also supported by the mapping of telomeric sequences. Phylograms based on Maximum Likelihood (ML) and Neighbor Joining (NJ) analyses grouped each ESU on particular highly supported clades, with the estimation of evolutionary divergence indicating values being higher than 3.8-12.3% among them. Our study reveals a huge degree of chromosomal and genetic diversity in B. coracoideus and highly points to the existence of four ESUs in allopatric and sympatric speciation processes. In fact, the high divergences found among the ESUs allowed us to delimitate lineages with taxonomic uncertainties in this nominal species.

19.
Cytogenet Genome Res ; 152(4): 194-203, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28942442

RESUMO

Ctenoluciidae is a Neotropical freshwater fish family whose representatives are known as bicudas. The genus Boulengerella contains 5 species, and 4 of them (B. cuvieri, B. lateristriga, B. lucius, and B. maculata) were cytogenetically analyzed in the present study by conventional and molecular procedures. All 4 species have a very similar karyotype, with 2n = 36 chromosomes (14 metacentrics + 16 submetacentrics + 6 subtelocentrics; FN = 72). However, the heterochromatin distribution pattern is species-specific. In all 4 species, the nucleolus organizer region is located in pair 18, as also confirmed by cytogenetic mapping of 18S rDNA. In turn, 5S rRNA genes are present in 2 chromosome pairs: in pair 1 of all 4 species, and in pair 10 of B. lateristriga, B. maculata, and B. cuvieri, but in pair 4 of B. lucius. The telomeric probe highlighted terminal regions in all chromosomes, as well as an interstitial centromeric sequence in pair 3 of the 3 first-mentioned species. Notably, a conspicuous heteromorphic secondary constriction in chromosomes 18 was found only in the males of the 3 species, rendering one of the homologs much larger than the other one. This feature, associated with a large 18S rDNA block and accumulation of telomeric sequences, suggests the presence of an XX/XY sex chromosome system in the analyzed Boulengerella species.


Assuntos
Caraciformes/classificação , Caraciformes/genética , Animais , Brasil , Bandeamento Cromossômico , Sequência Conservada , DNA Ribossômico/genética , Evolução Molecular , Feminino , Genoma , Hibridização in Situ Fluorescente , Cariotipagem , Masculino , RNA Ribossômico 18S/genética , RNA Ribossômico 5S/genética , Sequências Repetitivas de Ácido Nucleico , Cromossomo X/genética , Cromossomo Y/genética
20.
J Mol Model ; 23(10): 291, 2017 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-28951975

RESUMO

We determined multiple closed-shell Hartree-Fock-Roothaan solutions for the systems: BH, FH, LiH, and OH-, considering double and triple zeta bases. To calculate them, we used the self-consistent field method and the algebraic method. The Hartree-Fock solutions obtained were classified with respect to the kind of extreme. All these extremes generate the same configuration interaction space. Our key objective in this work is to illustrate that it is possible to obtain a wide variety of Hartree-Fock solutions for any molecular system.

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