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1.
Heredity (Edinb) ; 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39039117

RESUMEN

Neotropical fishes exhibit remarkable karyotype diversity, whose evolution is poorly understood. Here, we studied genetic differences in 60 individuals, from 11 localities of one species, the wolf fish Hoplias malabaricus, from populations that include six different "karyomorphs". These differ in Y-X chromosome differentiation, and, in several cases, by fusions with autosomes that have resulted in multiple sex chromosomes. Other differences are also observed in diploid chromosome numbers and morphologies. In an attempt to start understanding how this diversity was generated, we analyzed within- and between-population differences in a genome-wide sequence data set. We detect clear genotype differences between karyomorphs. Even in sympatry, samples with different karyomorphs differ more in sequence than samples from allopatric populations of the same karyomorph, suggesting that they represent populations that are to some degree reproductively isolated. However, sequence divergence between populations with different karyomorphs is remarkably low, suggesting that chromosome rearrangements may have evolved during a brief evolutionary time. We suggest that the karyotypic differences probably evolved in allopatry, in small populations that would have allowed rapid fixation of rearrangements, and that they became sympatric after their differentiation. Further studies are needed to test whether the karyotype differences contribute to reproductive isolation detected between some H. malabaricus karyomorphs.

2.
An Acad Bras Cienc ; 96(1): e20221011, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38597487

RESUMEN

Groupers (Epinephelidae and Serranidae) have attracted special attention to fish farming, and their species offer good opportunities for successful hybridizations. Cytogenetic data allow a better understanding of the role of karyotypic diversification in the acquisition of post-zygotic reproductive isolation (RI). Thus, chromosomal analyses were performed on E. striatus (Caribbean Sea), E. coioides and E. tauvina (Indo-Pacific Region), using standard procedures and mapping of six repetitive DNA classes by the in situ hybridization. The three species have 2n=48 chromosomes. The karyotypes of E. coioides and E. striatus are composed only of acrocentric chromosomes (FN=48), while E. tauvina has 8 submetacentric chromosomes (FN=56). Heterochromatin has a preferential centromeric distribution, and the microsatellite repeats are dispersed throughout the chromosomes of all species. The 18S and 5S rDNA sites are unique but show a colocalization arrangement in E. tauvina and E. striatus. The chromosomal organization suggests that the three species still maintain a significant amount of syntenic regions. The range of the karyotype divergence and the RI levels showed low, but goes turn proportionally greater in relation to the divergence time between the parental species. The slow acquisition of postzygotic RI is consistent with the high karyotype homogeneity presented by Epinephelidae family.


Asunto(s)
Lubina , Perciformes , Animales , Lubina/genética , Aislamiento Reproductivo , Cariotipo , Cariotipificación
3.
Int J Mol Sci ; 24(10)2023 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-37240350

RESUMEN

Scleropages formosus (Osteoglossiformes, Teleostei) represents one of the most valued ornamental fishes, yet it is critically endangered due to overexploitation and habitat destruction. This species encompasses three major color groups that naturally occur in allopatric populations, but the evolutionary and taxonomic relationships of S. formosus color varieties remain uncertain. Here, we utilized a range of molecular cytogenetic techniques to characterize the karyotypes of five S. formosus color phenotypes, which correspond to naturally occurring variants: the red ones (Super Red); the golden ones (Golden Crossback and Highback Golden); the green ones (Asian Green and Yellow Tail Silver). Additionally, we describe the satellitome of S. formosus (Highback Golden) by applying a high-throughput sequencing technology. All color phenotypes possessed the same karyotype structure 2n = 50 (8m/sm + 42st/a) and distribution of SatDNAs, but different chromosomal locations of rDNAs, which were involved in a chromosome size polymorphism. Our results show indications of population genetic structure and microstructure differences in karyotypes of the color phenotypes. However, the findings do not clearly back up the hypothesis that there are discrete lineages or evolutionary units among the color phenotypes of S. formosus, but another case of interspecific chromosome stasis cannot be excluded.


Asunto(s)
Genoma , Genómica , Animales , Peces/genética , Cariotipo , Análisis Citogenético
4.
Cytogenet Genome Res ; 161(3-4): 195-202, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34126615

RESUMEN

Ctenoluciidae (Characiformes), a family of freshwater fishes, comprises 2 genera, Ctenolucius and Boulengerella, with 7 recognized species. Up to now, only species of the genus Boulengerella have been subjected to cytogenetic studies. Here, we investigated the karyotype and other cytogenetic features of pike characin, Ctenolucius hujeta, using conventional (Giemsa staining, C-banding, Ag-NOR staining) and molecular (rDNA, telomeric sequences, and fiber-FISH mapping) procedures. This species has a diploid chromosome number of 2n = 36, and a karyotype composed of 12m + 20sm + 4a and FN = 68, similar to that found in Boulengerella species. However, differences regarding the number and distribution of several chromosomal markers support a distinct generic status. Colocalization of the 18S and 5S rDNA genes is an exclusive characteristic of the C. hujeta genome, with an interspersed distribution in the chromosomal fiber, an unusual phenomenon among eukaryotes. Additionally, our results support the view that Ctenoluciidae and Lebiasinidae families are closely related.


Asunto(s)
Characiformes/genética , Cromosomas/genética , Análisis Citogenético/métodos , Cariotipificación/métodos , Animales , Characiformes/clasificación , Bandeo Cromosómico , Diploidia , Evolución Molecular , Femenino , Genoma/genética , Hibridación Fluorescente in Situ/métodos , Cariotipo , Masculino , ARN Ribosómico 18S/genética , ARN Ribosómico 5S/genética , Telómero/genética
5.
Cytogenet Genome Res ; 160(9): 539-553, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33227787

RESUMEN

The family Aspredinidae comprises a clade of complex systematic relationships, both from molecular and morphological approaches. In this study, conventional and molecular cytogenetic studies coupled with nucleotide sequencing were performed in 6 Aspredininae species (Amaralia hypsiura, Bunocephalus cf. aloikae, Bunocephalus amaurus, Bunocephalus aff. coracoideus, Bunocephalus verrucosus, and Platystacus cotylephorus) from different locations of the Amazon hydrographic basin. Our results showed highly divergent diploid numbers (2n) among the species, ranging from 49 to 74, including the occurrence of an XX/X0 sex chromosome system. A neighbor-joining phylogram based on the cytochrome c oxidase I (COI) showed that Bunocephalus coracoideus is not a monophyletic clade, but closely related to B. verrucosus. The karyotypic data associated with COI suggest an ancestral karyotype for Aspredinidae with a reduced 2n, composed of bi-armed chromosomes and a trend toward chromosomal fissions resulting in higher diploid number karyotypes, mainly composed of acrocentric chromosomes. Evolutionary relationships were discussed under a phylogenetic context with related species from different Siluriformes families. The karyotype features and chromosomal diversity of Aspredinidae show an amazing differentiation, making this family a remarkable model for investigating the evolutionary dynamics in siluriforms as well as in fish as a whole.


Asunto(s)
Bagres/genética , Cromosomas/genética , Animales , Evolución Biológica , Brasil , Bagres/clasificación , Cromosomas/ultraestructura , Código de Barras del ADN Taxonómico , ADN Ribosómico/genética , Diploidia , Evolución Molecular , Femenino , Hibridación Fluorescente in Situ , Cariotipificación , Masculino , Filogenia , ARN Ribosómico 18S/genética , ARN Ribosómico 5S/genética , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido Nucleico , Cromosomas Sexuales/genética , Cromosomas Sexuales/ultraestructura , Especificidad de la Especie
6.
Int J Mol Sci ; 21(7)2020 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-32283616

RESUMEN

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.


Asunto(s)
Análisis Citogenético , Palaemonidae/genética , Animales , ADN Ribosómico/genética , Humanos , Hibridación Fluorescente in Situ , Cariotipo , Repeticiones de Microsatélite , Palaemonidae/clasificación
7.
Genet Mol Biol ; 43(4): e20200195, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33156892

RESUMEN

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.

8.
BMC Evol Biol ; 19(1): 73, 2019 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-30849933

RESUMEN

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.


Asunto(s)
Evolución Biológica , Cromosomas/genética , Especiación Genética , Variación Genética , Cariotipo , Smegmamorpha/genética , Animales , Bandeo Cromosómico , Mapeo Cromosómico , Geografía , Metafase/genética , Repeticiones de Microsatélite/genética , Tailandia
9.
Lancet ; 401(10390): 1770-1771, 2023 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-37244687
10.
Cytogenet Genome Res ; 157(4): 239-248, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30991393

RESUMEN

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.


Asunto(s)
Inversión Cromosómica , Cromosomas/genética , Peces/genética , Animales , Mapeo Cromosómico , Evolución Molecular , Peces/clasificación , Hibridación Fluorescente in Situ , Cariotipo , Cariotipificación , Filogenia
11.
Histopathology ; 75(5): 638-648, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31087672

RESUMEN

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.


Asunto(s)
Trasplante de Hígado , Necrosis Hepática Masiva/virología , Trasplantes/virología , Fiebre Amarilla , Virus de la Fiebre Amarilla , Adolescente , Adulto , Autopsia , Brasil , Humanos , Trasplante de Hígado/mortalidad , Masculino , Fiebre Amarilla/patología , Fiebre Amarilla/cirugía , Fiebre Amarilla/virología , Adulto Joven
12.
Planta ; 248(1): 197-209, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29675765

RESUMEN

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.


Asunto(s)
Antifúngicos/aislamiento & purificación , Proteínas de Plantas/aislamiento & purificación , Semillas/química , Quitinasas/aislamiento & purificación , Quitinasas/farmacología , Electroforesis en Gel de Poliacrilamida , Fabaceae/química , Fusarium/efectos de los fármacos , Lectinas/aislamiento & purificación , Lectinas/farmacología , Espectrometría de Masas , Microscopía Fluorescente , Proteínas de Plantas/farmacología , Proteómica , Bosque Lluvioso , Esporas Fúngicas/efectos de los fármacos
13.
HPB (Oxford) ; 20(8): 687-694, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29571616

RESUMEN

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.


Asunto(s)
Hepatectomía/métodos , Laparoscopía/métodos , Trasplante de Hígado/métodos , Donadores Vivos , Hepatectomía/efectos adversos , Hepatectomía/mortalidad , Humanos , Laparoscopía/efectos adversos , Laparoscopía/mortalidad , Trasplante de Hígado/efectos adversos , Trasplante de Hígado/mortalidad , Complicaciones Posoperatorias/etiología , Medición de Riesgo , Factores de Riesgo , Resultado del Tratamiento
14.
Cytogenet Genome Res ; 152(4): 194-203, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28942442

RESUMEN

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.


Asunto(s)
Characiformes/clasificación , Characiformes/genética , Animales , Brasil , Bandeo Cromosómico , Secuencia Conservada , ADN Ribosómico/genética , Evolución Molecular , Femenino , Genoma , Hibridación Fluorescente in Situ , Cariotipificación , Masculino , ARN Ribosómico 18S/genética , ARN Ribosómico 5S/genética , Secuencias Repetitivas de Ácidos Nucleicos , Cromosoma X/genética , Cromosoma Y/genética
15.
Cytogenet Genome Res ; 153(2): 96-104, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29186711

RESUMEN

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.


Asunto(s)
Cromosomas Sexuales/genética , Procesos de Determinación del Sexo , Tetraodontiformes/genética , Animales , Antígenos Nucleares/genética , Brasil , Bandeo Cromosómico , ADN Ribosómico/genética , Femenino , Amplificación de Genes , Hibridación Fluorescente in Situ , Masculino , ARN Ribosómico 18S/genética , Secuencias Repetitivas de Ácidos Nucleicos , Telómero/genética , Telómero/ultraestructura , Tropomiosina/genética
16.
Med Oral Patol Oral Cir Bucal ; 22(3): e354-e358, 2017 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-28390122

RESUMEN

BACKGROUND: Orbital apex syndrome (OAS) is a complex and uncommon disorder that typically damages multiple cranial nerves in association with optic nerve dysfunction. OAS is associated with several different pathologies, however; only a few cases have been reported in association with head and neck cancer (HNC) so far. MATERIAL AND METHODS: A case series of HNC patients diagnosed with OAS is described including clinicopathological data, image findings, and disease outcome. RESULTS: Ptosis and diplopia were diagnosed in four male patients with mean age of 61.2 years who were undergoing treatment for late-stage carcinomas of the tongue, larynx, and nasopharynx, eventually leading to the diagnosis of OAS. The mean overall survival rate after the diagnosis of OAS was 9.5 months. CONCLUSIONS: The current study reinforces evidence that OAS indicates poor prognosis and highlights the importance of early diagnosis.


Asunto(s)
Neoplasias de Cabeza y Cuello/complicaciones , Enfermedades del Nervio Óptico/etiología , Anciano , Enfermedades de los Nervios Craneales/etiología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Síndrome
17.
Cytogenet Genome Res ; 149(4): 312-320, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27710958

RESUMEN

The monophyletic order Osteoglossiformes represents one of the most ancestral groups of teleosts and has at least 1 representative in all continents of the southern hemisphere, with the exception of Antarctica. However, despite its phylogenetic and biogeographical importance, cytogenetic data in Osteoglossiformes are scarce. Here, karyotype and chromosomal characteristics of the lower Niger River population of the African butterfly fish Pantodon buchholzi, the sole species of the family Pantodontidae (Osteoglossiformes), were examined using conventional and molecular cytogenetic approaches. All specimens examined had 2n = 46 chromosomes, with a karyotype composed of 5 pairs of metacentric, 5 pairs of submetacentric, and 13 pairs of acrocentric chromosomes in both sexes. No morphologically differentiated sex chromosomes were identified. C-bands were located in the centromeric/pericentromeric region of all chromosomes and were associated with the single AgNOR site. FISH with ribosomal DNA probes revealed that both 5S and 18S rDNA were present in only 1 pair of chromosomes each, but did not colocalize. CMA3+ bands were observed near the telomeres in several chromosome pairs and also at the 18S rDNA sites. The mapping of di- and trinucleotide repeat motifs, Rex6 transposable element, and U2 snRNA showed a scattered distribution over most of the chromosomes, but for some microsatellites and the U2 snRNA also a preferential accumulation at telomeric regions. This study presents the first detailed cytogenetic analysis in the African butterfly fish by both conventional and molecular cytogenetic protocols. This is the first of a series of further cytogenetic and cytogenomic studies on osteoglossiforms, aiming to comprehensively examine the chromosomal evolution in this phylogenetically important fish order.


Asunto(s)
Análisis Citogenético , ADN Ribosómico/genética , Peces/clasificación , Peces/genética , Cariotipo , África , Animales , Bandeo Cromosómico , Elementos Transponibles de ADN/genética , Femenino , Hibridación Fluorescente in Situ , Masculino , Repeticiones de Microsatélite , Filogenia , ARN Ribosómico 18S/genética , Telómero/genética
18.
Hepatobiliary Pancreat Dis Int ; 15(1): 106-7, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26818551

RESUMEN

Portal vein thrombosis is a common complication in cirrhotic patients. When portal vein thrombectomy is not a suitable option, a large collateral vessel can be used for allograft venous inflow reconstruction. We describe an unusual case of successful portal revascularization using the right gastroepiploic vein. The patient underwent a cadaveric orthotopic liver transplantation with end-to-end anastomosis of the portal vein to the right gastroepiploic vein. Six months after liver transplantation the patient is well with good liver function. The use of the right gastroepiploic vein for allograft venous reconstruction is feasible and safe, with a great advantage of avoiding the need of venous jump graft.


Asunto(s)
Enfermedad Hepática en Estado Terminal/cirugía , Arteria Gastroepiploica/cirugía , Trasplante de Hígado/métodos , Vena Porta/cirugía , Trombosis de la Vena/etiología , Aloinjertos , Anastomosis Quirúrgica , Enfermedad Hepática en Estado Terminal/diagnóstico , Enfermedad Hepática en Estado Terminal/etiología , Femenino , Arteria Gastroepiploica/diagnóstico por imagen , Humanos , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Flebografía/métodos , Vena Porta/diagnóstico por imagen , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Trombosis de la Vena/diagnóstico
19.
Rev Panam Salud Publica ; 40(5): 332-340, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28076582

RESUMEN

OBJECTIVE: To identify interventions that facilitate sustainable jobs and have a positive impact on the health of workers in health sector workplaces. METHODS: This overview utilized systematic review methods to synthesize evidence from multiple systematic reviews and economic evaluations. A comprehensive search was conducted based on a predefined protocol, including specific inclusion criteria. To be classified as "sustainable," interventions needed to aim (explicitly or implicitly) to 1) have a positive impact on at least two key dimensions of the integrated framework for sustainable development and 2) include measures of health impact. Only interventions conducted in, or applicable to, health sector workplaces were included. RESULTS: Fourteen systematic reviews and no economic evaluations met the inclusion criteria for the overview. The interventions that had a positive impact on health included 1) enforcement of occupational health and safety regulations; 2) use of the "degree of experience rating" feature of workers' compensation; 3) provision of flexible working arrangements that increase worker control and choice; 4) implementation of certain organizational changes to shift work schedules; and 5) use of some employee participation schemes. Interventions with negative impacts on health included 1) downsizing/restructuring; 2) temporary and insecure work arrangements; 3) outsourcing/home-based work arrangements; and 4) some forms of task restructuring. CONCLUSIONS: What is needed now is careful implementation, in health sector workplaces, of interventions likely to have positive impacts, but with careful evaluation of their effects including possible adverse impacts. Well-evaluated implementation of the interventions (including those at the pilot-study stage) will contribute to the evidence base and inform future action. Interventions with negative health impacts should be withdrawn from practice (through regulation, where possible). If use of these interventions is necessary, for other reasons, considerable care should be taken to ensure an appropriate balance between business needs and human health and well-being.


Asunto(s)
Salud Laboral , Ocupaciones , Conservación de los Recursos Naturales , Análisis Costo-Beneficio , Humanos , Proyectos Piloto , Literatura de Revisión como Asunto
20.
Rev Panam Salud Publica ; 39(4): 200-7, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27657185

RESUMEN

Objective To inform policy by providing an overview of systematic reviews on interventions that facilitate sustainable energy use and have a positive impact on health. Methods Systematic review methods were used to synthesize evidence from multiple systematic reviews and economic evaluations through a comprehensive search of 13 databases and nine websites based on a pre-defined protocol, including clear inclusion criteria. Both grey and peer-reviewed literature published in English, Spanish, and Portuguese during the 17 years from January 1997 - January 2014 was included. To classify as "sustainable," interventions needed to aim to positively impact at least two dimensions of the integrated framework for sustainable development and include measures of health impact. Results Five systematic reviews and one economic evaluation met the inclusion criteria. The most promising interventions that impacted health were electricity for lighting and other uses (developing countries); improved stoves for cooking and health and/or cleaner fuels for cooking (developing countries); and household energy efficiency measures (developed countries). These interventions also had potential environmental and economic impacts. Their cost-effectiveness is not known, nor is their impact on health inequalities. Conclusions What is needed now is careful implementation of interventions where the impacts are likely to be positive but their implementation needs to be rigorously evaluated, including possible adverse impacts. Care needs to be taken not to exacerbate health inequalities and to consider context, human behavior and cultural factors so that the potential health benefits are realized in real-life implementation. Possible impact on health inequalities needs to be considered and measured in future primary studies and systematic reviews.


Asunto(s)
Conservación de los Recursos Energéticos , Salud Pública , Culinaria , Análisis Costo-Beneficio , Electricidad , Predicción , Humanos , Aceites , Literatura de Revisión como Asunto
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