Consenso sobre Ecocardiografia Transesofágica Perioperatória da Sociedade Brasileira de Anestesiologia e do Departamento de Imagem Cardiovascular da Sociedade Brasileira de Cardiologia

Through the Life Cycle of Intraoperative Transesophageal Echocardiography (ETTI/SBA) the Brazilian Society of Anesthesiology, together with the Department of Cardiovascular Image of the Brazilian Society of Cardiology (DIC/SBC), createded a task force to standardize the use of intraoperative transesophageal echocardiography by Brazilian anesthesiologists and echocardiographers based on scientific evidence from the Society of Cardiovascular Anesthesiologists/American Society of Echocardiography (SCA/ASE) and the Brazilian Society of Cardiology.     

Effects of auditory training in individuals with high-frequency hearing loss

OBJECTIVE:To determine the effects of a formal auditory training program on the behavioral, electrophysiological and subjective aspects of auditory function in individuals with bilateral high-frequency hearing loss.METHOD:A prospective study of seven individuals aged 46 to 57 years with symmetric, moderate high-frequency hearing loss ranging from 3 to 8 kHz was conducted. Evaluations of auditory processing (sound location, verbal and non-verbal sequential memory tests, the speech-in-noise test, the staggered spondaic word test, synthetic sentence identification with competitive ipsilateral and contralateral competitive messages, random gap detection and the standard duration test), auditory brainstem response and long-latency potentials and the administration of the Abbreviated Profile of Hearing Aid Benefit questionnaire were performed in a sound booth before and immediately after formal auditory training.RESULTS:All of the participants demonstrated abnormal pre-training long-latency characteristics (abnormal latency or absence of the P3 component) and these abnormal characteristics were maintained in six of the seven individuals at the post-training evaluation. No significant differences were found between ears in the quantitative analysis of auditory brainstem responses or long-latency potentials. However, the subjects demonstrated improvements on all behavioral tests. For the questionnaire, the difference on the background noise subscale achieved statistical significance.CONCLUSION:Auditory training in adults with high-frequency hearing loss led to improvements in figure-background hearing skills for verbal sounds, temporal ordination and resolution, and communication in noisy environments. Electrophysiological changes were also observed because, after the training, some long latency components that were absent pre-training were observed during the re-evaluation.     

The multiple facets of drug resistance: one history,different approaches

Some cancers like melanoma and pancreatic and ovarian cancers, for example, commonly display resistance to chemotherapy, and this is the major obstacle to a better prognosis of patients. Frequently, literature presents studies in monolayer cell cultures, 3D cell cultures or in vivo studies, but rarely the same work compares results of drug resistance in different models. Several of these works are presented in this review and show that usually cells in 3D culture are more resistant to drugs than monolayer cultured cells due to different mechanisms. Searching for new strategies to sensitize different tumors to chemotherapy, many methods have been studied to understand the mechanisms whereby cancer cells acquire drug resistance. These methods have been strongly advanced along the years and therapies using different drugs have been increasingly proposed to induce cell death in resistant cells of different cancers. Recently, cancer stem cells (CSCs) have been extensively studied because they would be the only cells capable of sustaining tumorigenesis. It is believed that the resistance of CSCs to currently used chemotherapeutics is a major contributing factor in cancer recurrence and later metastasis development. This review aims to appraise the experimental progress in the study of acquired drug resistance of cancer cells in different models as well as to understand the role of CSCs as the major contributing factor in cancer recurrence and metastasis development, describing how CSCs can be identified and isolated.     

Endogenous protein phosphorylation by resting and activated human neutrophils

NADPH oxidase is an enzyme in the plasma membrane of the neutrophil that catalyzes the production of O2-, a species central to the oxygen- dependent killing mechanisms of this cell. The oxidase is dormant in resting cells and is activated upon the addition of a stimulus. Neutrophils of patients with chronic granulomatous disease (CGD) manifest no oxidase activity when stimulated. The possible role of protein phosphorylation in the activation of NADPH oxidase was examined in normal and CGD neutrophils by measuring the incorporation of 32Pi into proteins as determined by gel electrophoresis followed by autoradiography. Resting neutrophils from normal subjects exhibit at least 40 distinct phosphoprotein bands. The level of phosphorylation of these bands was examined after the addition of phorbol myristate acetate (PMA), opsonized zymosan, digitonin, N-formyl-methionyl- phenylalanine (FMLP), or NaF. PMA and opsonized zymosan increased the phosphorylation of a set of 6 protein bands. Digitonin and FMLP consistently caused the phosphorylation of 4 of these protein bands, while NaF failed to induce increased phosphorylation of any protein band. All activators tested caused the dephosphorylation of one specific protein band. The time course of phosphorylation (dephosphorylation) was examined using PMA as the activating agent. Increased phosphorylation of one protein band was evident by 12 sec after the addition of PMA. The most slowly phosphorylated protein band did not slow evidence of change until 5 min after the addition of PMA. Three of the phosphoproteins examined were phosphorylated either earlier than or concomitant with the activation of NADPH oxidase. CGD neutrophils were compared with normal cells for their ability to phosphorylate proteins in response to PMA. The phosphoprotein banding patterns of CGD neutrophils were identical with those of normal neutrophils in both the resting and activated states. The evidence presented shows that the phosphorylation of proteins is a prominent feature of neutrophil metabolism. The striking similarity of phosphorylation changes induced by the various activators tested suggests that protein phosphorylation may play a role in some aspects of neutrophil activation. Evidence was not obtained, however, regarding a link between protein phosphorylation and activation of NADPH oxidase.     

Role of plasminogen activator inhibitor-1 in promoting fibrin deposition in rabbits infused with ancrod or thrombin

The role of defective fibrinolysis caused by elevated activity of plasminogen activator inhibitor-1 (PAI-1) in promoting fibrin deposition in vivo has not been well established. The present study compared the efficacy of thrombin or ancrod, a venom-derived enzyme that clots fibrinogen, to induce fibrin formation in rabbits with elevated PAI-1 levels. One set of male New Zealand rabbits received intravenous endotoxin to increase endogenous PAI-1 activity followed by a 1-hour infusion of ancrod or thrombin; another set of normal rabbits received intravenous human recombinant PAI-1 (rPAI-1) during an infusion of ancrod or thrombin. Thirty minutes after the end of the infusion, renal fibrin deposition was assessed by histopathology. Animals receiving endotoxin, rPAI-1, ancrod, or thrombin alone did not develop renal thrombi. All endotoxin-treated rabbits developed fibrin deposition when infused with ancrod (n = 4) or thrombin (n = 6). Fibrin deposition occurred in 7 of 7 rabbits receiving both rPAI-1 and ancrod and in only 1 of 6 receiving rPAI-1 and thrombin (P < .01). In vitro, thrombin but not ancrod was inactivated by normal rabbit plasma and by purified antithrombin III or thrombomodulin. The data indicate that elevated levels of PAI-1 promote fibrin deposition in rabbits infused with ancrod but not with thrombin. In endotoxin-treated rabbits, fibrin deposition that occurs with thrombin infusion may be caused by decreased inhibition of procoagulant activity and not increased PAI-1 activity.