RESUMO
BACKGROUND: One limitation of the direct thrombin inhibitor dabigatran is the lack of specific antidotes that allow acute bleeding events to be managed or urgent interventional procedures performed. Prothrombin complex concentrates (PCCs) have served as a standard treatment for the reversal of coumarin anticoagulation. OBJECTIVES: This study was designed to determine in an animal model whether a PCC (Beriplex P/N) can effectively reverse the effects of dabigatran. An additional objective was to evaluate markers of dabigatran-associated bleeding diathesis. METHODS: Anesthetized rabbits were treated with 0.4 mg kg(-1) dabigatran followed by PCC doses of 20, 35 or 50 IU kg(-1) or placebo. After a standardized kidney incision, volume of blood loss and time to hemostasis were determined. RESULTS: From an initial mean of 29 mL, blood loss progressively declined by 5.44 mL with a 95% confidence interval (CI) of 2.21-8.67 mL per 10 IU kg(-1) increment in PCC dose (P = 0.002). At a PCC dose of 50 IU kg(-1) blood loss was fully normalized. Increasing PCC doses shortened the median time to hemostasis from 20.0 to 5.7 min (P < 0.001). The rate of hemostasis was nearly trebled with each 10 IU kg(-1) increment in PCC dose (rate ratio, 2.89; CI, 1.64-5.09). CONCLUSIONS: In this animal study, PCC showed potential as an agent for reversing the effects of dabigatran. Further investigation is warranted.
Assuntos
Anticoagulantes/farmacologia , Benzimidazóis/farmacologia , Fator IX/farmacologia , Fator VII/farmacologia , Fator X/farmacologia , Modelos Animais , Protrombina/farmacologia , beta-Alanina/análogos & derivados , Animais , Anticoagulantes/antagonistas & inibidores , Anticoagulantes/sangue , Benzimidazóis/antagonistas & inibidores , Benzimidazóis/sangue , Dabigatrana , Combinação de Medicamentos , Feminino , Placebos , Coelhos , beta-Alanina/antagonistas & inibidores , beta-Alanina/sangue , beta-Alanina/farmacologiaRESUMO
Twenty-five specimens of lowland gorilla, including 24 specimens of the western lowland gorilla (Gorilla gorilla gorilla) and 1 specimen of the eastern lowland gorilla (G. gorilla graueri), were investigated by fluorescence in situ hybridization with a human-derived 18S + 28S rDNA probe. Specific hybridization was constitutively seen on the short arms of gorilla acrocentric chromosome pairs 22 and 23, corresponding to human pairs 21 and 22. Only one specimen of western lowland gorilla investigated showed an additional hybridization site at the telomeric short arm of one chromosome 1. From our own results and those in the literature, it is clear that the additional rDNA site on chromosome 1 must be regarded as a rare polymorphism in the subspecies of western lowland gorilla, possibly going back to a founder translocation event.
Assuntos
Mapeamento Cromossômico , DNA Ribossômico , Gorilla gorilla/genética , Animais , Feminino , Humanos , Hibridização in Situ Fluorescente , MasculinoRESUMO
The three human male specific expressed gene families DAZ, RBM, and TSPY are known to be repetitively clustered in the Y-specific region of the human Y Chromosome (Chr). RBM and TSPY are Y-specifically conserved in simians, whereas DAZ cannot be detected on the Y chromosomes of New World monkeys. The proximity of SRY to the pseudoautosomal region (PAR) is highly conserved and thus most effectively stabilizes the pseudoautosomal boundary on the Y (PABY) in simians. In contrast, the non-recombining part of the Y Chrs, including DAZ, RBM, and TSPY, was exposed to species-specific amplifications, diversifications, and rearrangements. Evolutionary fast fixation of any of these variations was possible as long as they did not interfere with male fertility.
Assuntos
Mapeamento Cromossômico , Proteínas de Ligação a DNA/genética , Rearranjo Gênico , Haplorrinos/genética , Proteínas Nucleares , Proteínas de Ligação a RNA/genética , Fatores de Transcrição , Cromossomo Y , Animais , Proteína 1 Suprimida em Azoospermia , Haplorrinos/classificação , Hominidae/genética , Hylobates/genética , Masculino , Filogenia , Proteína da Região Y Determinante do Sexo , Especificidade da EspécieRESUMO
Several genes located within or proximal to the human PAR in Xp22 have homologues on the Y chromosome and escape, or partly escape, inactivation. To study the evolution of Xp22 genes and their Y homologues, we applied multicolour fluorescence in situ hybridization (FISH) to comparatively map DNA probes for the genes ANT3, XG, ARSD, ARSE (CDPX), PRK, STS, KAL and AMEL to prometaphase chromosomes of the human species and hominoid apes. We demonstrate that the genes residing proximal to the PAR have a highly conserved order on the higher primate X chromosomes but show considerable rearrangements on the Y chromosomes of hominoids. These rearrangements cannot be traced back to a simple model involving only a single or a few evolutionary events. The linear instability of the Y chromosomes gives some insight into the evolutionary isolation of large parts of the Y chromosomes and thus might reflect the isolated evolutionary history of the primate species over millions of years.
Assuntos
Evolução Biológica , Haplorrinos/genética , Hominidae/genética , Cromossomo X/genética , Cromossomo Y/genética , Animais , Mapeamento Cromossômico , Sondas de DNA , Genes , Humanos , Hibridização in Situ Fluorescente/métodos , Homologia de Sequência do Ácido NucleicoRESUMO
A 12.5-year-old male patient with a de novo derivative chromosome 22 is reported. A detailed description of the clinical features and comparison with the results of conventional cytogenetic banding methods indicated that the derivative chromosome might have been caused by a translocation between the short arms of chromosomes 12 and 22: der(22)t(12;22)(p12.1;p11.2). Fluorescence in situ hybridization with a chromosome 12-specific paint confirmed this supposition. The patient thus carries a pure duplication of 12pter-->p12.1. The phenotype of the patient described is compared to cases in the literature.
Assuntos
Cromossomos Humanos Par 12/genética , Cromossomos Humanos Par 22/genética , Translocação Genética , Adolescente , Fácies , Humanos , Hibridização in Situ Fluorescente , Masculino , FenótipoRESUMO
Genes within the differential region of the human Y chromosome do not recombine, and therefore the determination of their location depends on physical mapping. Yeast artificial chromosome (YAC) contigs spanning the euchromatic region of the human Y have become a powerful tool for the generation of an overlapping clone map. With this approach, however, complete physical mapping is difficult in Y euchromatic regions that are rich in repetitive sequences. We have, therefore, made use of the fluorescence in situ hybridization technique as an alternative strategy for physically mapping the PRKY and AMELY genes as well as the TSPY, RBM and DAZ gene families to human Y chromosomes in prometaphase and to extended Y chromatin in interphase. From our results, the following order of gene sequences in interval 3 of the short arm of the human Y chromosome is suggested: TSPY major with few RBM sequences interspersed-PRKY-AMELY-TSPY minor with few RBM sequences interspersed-cen. On the long arm, RBM sequences appear to be distributed over wide regions of intervals 5 and 6 with few TSPY sequences interspersed. Distal to an RBM signal cluster, a large cluster of DAZ signals is located with only a few DAZ and RBM signals overlapping in between the two clusters.
Assuntos
Cromatina , Mapeamento Cromossômico , Hibridização in Situ Fluorescente , Fatores de Transcrição , Cromossomo Y/genética , Proteínas de Ciclo Celular , Centrômero , Cromatina/genética , Mapeamento Cromossômico/métodos , Cromossomos Artificiais de Levedura , Cosmídeos , Sondas de DNA , DNA Satélite , Proteínas de Ligação a DNA/genética , Proteína 1 Suprimida em Azoospermia , Ligação Genética , Humanos , Interfase , Metáfase , Microscopia de Fluorescência , Família Multigênica/genética , Proteínas Nucleares/genética , Proteínas de Ligação a RNA/genética , Sequências Repetitivas de Ácido Nucleico , Proteína da Região Y Determinante do SexoRESUMO
We report on a male patient with a de novo derivative chromosome 9. From clinical and conventional cytogenetic data, it was assumed that the derivative chromosome might be caused by a translocation between the short arms of chromosomes 7 and 9: der(9)t(7;9)(p21.2;p23.5). Fluorescence in situ hybridization with a chromosome 7-specific and a chromosome 9-specific paint confirmed this supposition. The phenotype of the patient described is compared to cases in the literature.
Assuntos
Anormalidades Múltiplas/genética , Aberrações Cromossômicas/genética , Deleção Cromossômica , Cromossomos Humanos Par 7 , Cromossomos Humanos Par 9 , Adulto , Amniocentese , Transtornos Cromossômicos , Edema/diagnóstico por imagem , Feminino , Doenças Fetais/diagnóstico por imagem , Doenças Fetais/genética , Transtornos do Crescimento/genética , Humanos , Lactente , Recém-Nascido , Masculino , Gravidez , Transtornos Psicomotores/genética , UltrassonografiaRESUMO
Applying two-colour fluorescence in situ hybridization (FISH) we simultaneously hybridized RBM- and TSPY-related cosmids to Y chromosomes in prophase and to released Y chromatin in interphase nuclei of man and pygmy chimpanzee. Whereas, even on prophasic Y chromosomes, no resolution of the overlapping RBM and TSPY signal clusters could be achieved, the RBM and TSPY signals are completely separated from each other in our maximum released Y chromatin stretches in interphase nuclei. These results unequivocally lend support to the view that the RBM and TSPY families have an interspersed organization on the Y chromosomes of man and higher apes. Thus, the distribution of RBM and TSPY signals might well go back to a common organization of these genes next to each other on an ancient Y chromosome.
Assuntos
Cosmídeos/genética , Proteínas de Ligação a DNA/genética , Hominidae/genética , Hibridização in Situ Fluorescente , Proteínas Nucleares , Pan troglodytes/genética , Sequências Reguladoras de Ácido Nucleico , Fatores de Transcrição , Cromossomo Y/genética , Animais , Proteínas de Ciclo Celular , Humanos , Interfase , Masculino , RNA/metabolismo , Proteína da Região Y Determinante do Sexo , Especificidade da Espécie , Cromossomo Y/ultraestruturaRESUMO
Using chromosomal in situ hybridization it has been demonstrated that specific members of the YRRM and the TSPY families are multicopy and Y chromosome specific in hominoids. After hybridization with the YRRM-related cosmid A5F and the TSPY-related cosmids cos36 and cY91, a reverse and complementary pattern of main and secondary signals is detected on the Y chromosomes of the human, the pygmy chimpanzee and the gorilla, while the location of signals coincides on the Y chromosomes of the chimpanzee, both orang-utan subspecies and the white hand gibbon. This complementary distribution of YRRM and TSPY sequences on the hominoid Y chromosomes possibly originates from a similar sequence motif that is shared by and evolutionarily conserved between certain members of both gene families and/or repeated elements flanking those genes. Otherwise this complementary distribution could go back to a common organization of these genes next to each other on an ancient Y chromosome which was disrupted by chromosomal rearrangements and amplification of one or other of the genes at each of the locations.
Assuntos
Proteínas de Ligação a DNA/genética , Hominidae/genética , Proteínas Nucleares , Diferenciação Sexual/genética , Espermatogênese/genética , Fatores de Transcrição , Cromossomo Y , Animais , Sequência de Bases , Proteínas de Ciclo Celular , Mapeamento Cromossômico , Sequência Conservada , Cosmídeos/genética , Humanos , Hylobates/genética , Hibridização in Situ Fluorescente/métodos , Masculino , Proteína da Região Y Determinante do SexoRESUMO
Cytogenetic studies of the primate Y chromosomes have suggested that extensive rearrangements have occurred during evolution of the great apes. We have used in situ hybridization to define these rearrangements at the molecular level. pHU-14, a probe including sequences from the sex determining gene SRY, hybridizes close to the early replicating pseudoautosomal segment in a telomeric or subtelomeric position of the Y chromosomes of all great apes. The low copy repeat detected by the probe Fr35-II is obviously included in Y chromosomal rearrangements during hominid evolution. These results, combined with previous studies, suggest that the Y chromosome in great apes has a conserved region including the pseudoautosomal region and the testis-determining region. The rest of the Y chromosome has undergone several rearrangements in the different great apes.
