RESUMO
Arenediazonium ions (ArN2+) are genotoxic though the source of their genotoxicity is unknown. The present studies were undertaken to determine if reductive decomposition of ArN2+ to aryl radicals (Ar) in the presence of calf thymus DNA (ctDNA) or in cells results in the formation of DNA adducts. We found that when arenediazonium ions of the general structure p-X-ArN2+ (X = CH3, CH2OCH3, CH2OH) are allowed to react with ctDNA or incubated with cells under conditions that produce p-X-Ar, DNA adducts are formed with guanine. The structure of the adduct is the C8-substitution product derived from guanine and p-X-Ar. Formation of p-X-Ar was determined by ESR spin-trapping with 5,5-dimethyl-1-pyrroline N-oxide (DMPO). The extent of C8-arylguanine adduction was measured by high performance liquid chromatography (HPLC) analysis of the DNA hydrosylate and comparison with authentic synthetic standards. The C8-arylguanine adducts observed to form may be important in regard to the genotoxicity of ArN2+, though other DNA adducts such as the N6-triazene of adenine or C8-aryladenine adducts can form. Finally, though the formation of C8-arylguanine adducts from arenediazonium ions has been proposed, this is the first report demonstrating their formation in DNA.
Assuntos
Adutos de DNA , Compostos de Diazônio/toxicidade , Guanina/química , Micotoxinas/química , Animais , Sistema Livre de Células , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Compostos de Diazônio/química , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres , Queratinócitos , CamundongosRESUMO
A brief conceptual history of neurovascular compression in the thoracic outlet with emphasis on surgical intervention is presented. After the description of techniques for the removal of the first rib in 1962 and 1966, an explosion of operations for thoracic outlet syndromes occurred during the next two decades. A critical reappraisal by several experienced surgeons has led to a re-examination of the indications for surgical intervention. Serious complications involving the brachial plexus and the subclavian artery and vein have unfortunately led to widespread litigation. An attempt is made to define the place of diagnostic and therapeutic modalities that will encourage a favorable outcome in most patients.
Assuntos
Síndrome do Desfiladeiro Torácico/cirurgia , Clavícula/cirurgia , Humanos , Métodos , Complicações Pós-Operatórias , Costelas/cirurgia , Síndrome do Desfiladeiro Torácico/diagnósticoAssuntos
Prótese Vascular , Idoso , Braço/irrigação sanguínea , Artéria Axilar/cirurgia , Feminino , Humanos , Isquemia/cirurgia , Falha de PróteseRESUMO
Postoperatively, wound infections in arterial procedures may have calamitous consequences with loss of limb and of life and is associated with significant financial, physical and emotional upsets by patients. Good surgical technique carried out in a clean operating room and hospital environment has a postoperative rate of wound infection of 1 to 5 per cent. By using intermittent intraoperative antibiotic wound irrigation, the postoperative rate of wound infection can be reduced to the vanishing point, that is, 0.1 per cent.
Assuntos
Antibacterianos/administração & dosagem , Cuidados Intraoperatórios/métodos , Infecção da Ferida Cirúrgica/prevenção & controle , Irrigação Terapêutica/métodos , Administração Tópica , Antibacterianos/farmacologia , Cefalotina/sangue , Humanos , Canamicina/sangue , Staphylococcus/efeitos dos fármacosRESUMO
Intermittent intraoperative antibiotic irrigation from the beginning of an operative procedure to its completion is a valuable supplement to hospital and operating room cleanliness and to good surgical technique. A prospective, randomized, double-blind study of 200 patients undergoing clean-contaminated operations on the gastrointestinal tract demonstrated a marked reduction in the incidence of postoperative wound infection and absolute prevention of postoperative peritonitis.
Assuntos
Antibacterianos/administração & dosagem , Procedimentos Cirúrgicos do Sistema Biliar , Colo/cirurgia , Estômago/cirurgia , Infecção da Ferida Cirúrgica/prevenção & controle , Cefalotina/administração & dosagem , Ensaios Clínicos como Assunto , Método Duplo-Cego , Feminino , Humanos , Canamicina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Distribuição Aleatória , Irrigação TerapêuticaRESUMO
Intraoperative antibiotic wound lavage has been used in all arterial reconstructive procedures for the past 7 years and reduced the incidence of early and late postoperative infections from 1.5% in 400 operations prior to 1969 to 0.23% (one post-hospital) in 434 patients operated since that date. In 226 consecutive clean major general surgical procedures since June 1971 there has been no early or late wound infections following intraoperative antibiotic wound lavage in contrast to an infection rate of 1.5% in 185 operations prior to that date. A double blind study of 200 patients undergoing operations for varicose veins was carried out as follows: The wounds of alternate patients were irrigated either with normal saline or with antibiotic solution. There were no gross (grade II) postoperative wound infections. Minor skin changes were noted in 93 of 632 incisions in the saline group and only 49 of 608 incisions irrigated with antibiotic solution (P less than 0.001). In clean operations without antibiotic wound lavage there was a 0.73% rate of in-hospital wound infections in 685 patients in contrast to a zero rate in 760 patients wherein intraoperative wound lavage was carried out throughout the operative procedure.
