RESUMO
The authors report a rare case of hemangioendothelioma of the right innominate vein complicated by superior vena cava syndrome. Considering development of enlarged venous collaterals, we performed circular resection of superior vena cava together with the right and left innominate veins without replacement. There were no postoperative complications. The use of vascular prosthesis in patients with long-standing superior vena cava compression and enlarged collaterals is associated with high risk of thrombosis and subsequent pulmonary embolism. Safe circular resection of superior vena cava without replacement is possible after intraoperative test clamping.
Assuntos
Hemangioendotelioma , Síndrome da Veia Cava Superior , Trombose , Veias Braquiocefálicas/diagnóstico por imagem , Veias Braquiocefálicas/cirurgia , Humanos , Síndrome da Veia Cava Superior/etiologia , Síndrome da Veia Cava Superior/cirurgia , Trombose/complicações , Veia Cava Superior/cirurgiaRESUMO
DNA glycosylases are enzymes that initiate base excision repair, a process of removal of damaged bases from the cellular DNA. Recent data show that variants of two human DNA glycosylases, MUTYH and OGG1, are associated with an increased risk of cancer. In addition, activities of various DNA glycosylases have been implicated in protection of humans from neurodegenerative diseases, immune disorders and viral infections. On the other hand, DNA glycosylases from pathogenic microorganisms help them to avoid the host defensive systems. Thus, DNA glycosylases represent both potential therapeutic agents and drug targets.
Assuntos
Infecções Bacterianas/enzimologia , Transformação Celular Neoplásica/metabolismo , DNA Glicosilases/fisiologia , Reparo do DNA/fisiologia , Doenças Genéticas Inatas/enzimologia , Viroses/enzimologia , Sequência de Aminoácidos , Infecções Bacterianas/genética , Dano ao DNA/genética , Dano ao DNA/fisiologia , DNA Glicosilases/genética , Reparo do DNA/genética , Doenças Genéticas Inatas/genética , Humanos , Doenças do Sistema Imunitário/enzimologia , Doenças do Sistema Imunitário/genética , Dados de Sequência Molecular , Mutação , Doenças Neurodegenerativas/enzimologia , Doenças Neurodegenerativas/genética , Viroses/genéticaRESUMO
An analysis of pollination system in Aristolochia manshuriensis has shown that flower structure in this species is strictly adapted to cross-pollination, but the possibility of an autogamous or geitonogamous type of self-pollination with the involvement of insects is not excluded. The flowers of A. manshuriensis are most frequently visited by flies of the family Anthomyiidae, which markedly contribute to their pollination. Males account for 65% of pollinator insects collected from the flowers.
Assuntos
Aristolochia/fisiologia , Flores/fisiologia , Polinização/fisiologia , Aristolochia/anatomia & histologia , Flores/anatomia & histologiaRESUMO
Oxidized bases are removed from DNA of Escherichia coli by enzymes formamidopyrimidine DNA glycosylase (Eco-Fpg) and endonuclease VIII (Eco-Nei) of the same structural family Fpg/Nei. New homologs of these enzymes not characterized earlier have been found in genomes of Actinobacteria. We have cloned and expressed two paralogs (Mtu-Nei2 and Mtu-Fpg2) from 36KAZ and KHA94 isolates of Mycobacterium tuberculosis and studied their ability to participate in DNA repair. Under heterologous expression in E. coli, Mtu-Nei2 decreased the rate of spontaneous mutagenesis in the rpoB gene, whereas Mtu-Fpg2 moderately increased it, possibly due to absence of residues crucially important for catalysis in this protein. Mtu-Nei2 was highly active toward double-stranded DNA substrates containing dihydrouracil residues and apurine-apyrimidine sites and was less efficient in cleavage of substrates containing 8-oxoguanine and uracil residues. These lesions, as well as 8-oxoadenine residues, were also recognized and removed by the enzyme from single-stranded DNA. Fpg and Nei homologs from M. tuberculosis can play an important role in protection of bacteria against genotoxic stress caused by oxidative burst in macrophages.
Assuntos
Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Reparo do DNA , DNA-Formamidopirimidina Glicosilase/genética , Desoxirribonuclease (Dímero de Pirimidina)/genética , Desoxirribonuclease (Dímero de Pirimidina)/metabolismo , Mycobacterium tuberculosis/enzimologia , Sequência de Aminoácidos , Proteínas de Bactérias/química , Clonagem Molecular , DNA-Formamidopirimidina Glicosilase/química , Desoxirribonuclease (Dímero de Pirimidina)/química , Escherichia coli/genética , Teste de Complementação Genética , Dados de Sequência Molecular , Mycobacterium tuberculosis/genética , Proteínas Recombinantes/isolamento & purificação , Homologia de Sequência de Aminoácidos , Especificidade por SubstratoRESUMO
The authors treated acute arterial obstruction in 190 patients. A complex of diagnostic and therapeutic measures, including the establishment of indications for operative treatment, development of tactics, use of ++physico-technical methods (ultrasound study, rheography, electrocardiography, ++roentgeno-contrast angiography, ultra-violet blood irradiation, electromyostimulation) was developed. A positive result of treatment was obtained in 78.9% of patients, incidence of an amputation performance was 13.7% lethality--12.6%.