Taís Burmann de Mendonça

Topical hepatic hypothermia plus ischemic preconditioning: analysis of bile flow and ischemic injuries after initial reperfusion in rats

PURPOSE To evaluate the effects of the topical liver hypothermia and IPC combination against I/R injury after initial reperfusion. METHODS In 32 Wistar rats, partial liver ischemia was induced for 90 minutes in normothermia (IN), ischemic preconditioning (IPC), 26ºC topical hypothermia (H) and 26ºC topical hypothermia plus IPC (H+IPC). MAP, body temperature and bile flow were recorded each 15 minutes. Plasmatic injury markers and tissue antioxidant defenses were assessed after 120 minutes of reperfusion. RESULTS MAP and body temperature remained constant during all experiment. Bile flow returned to levels similar to controls after 45 minutes of reperfusion in the H and H+IPC groups and increased significantly in comparison to the NI and IPC groups after 105 and 120 minutes. AST and ALT increased significantly in the normothermic groups in comparison to controls. TBARS levels decreased significantly in the H+IPC group in comparison to the other groups whereas Catalase levels increased significantly in the IPC group. SOD levels were significantly higher in the H group in comparison to all groups. CONCLUSION The induction of 26ºC topical hypothermia associated or not to IPC protected the ischemic liver against ischemia/reperfusion injuries and allowed an early recovery of the hepatic function.

Intraocular pressure in very low birth weight preterm infants and its association with postconceptional age

OBJECTIVE: To evaluate intraocular pressure in very low birth weight preterm infants and correlate it with postconceptional age. METHODS: The intraocular pressure in a prospective cohort of very low birth weight premature infants (defined as a birth weight ≤1,500 g and gestational age ≤32 weeks) admitted to Hospital de Clínicas de Porto Alegre, Brazil was evaluated weekly. The evaluated outcome was the variation in the intraocular pressure following changes in the postconceptional age (defined as the gestational age at birth plus the age in weeks at the time of examination) in the weeks following preterm birth. Mixed-effects models were used for the statistical analysis to determine the intraocular pressure variation according to postconceptional age, and means and 10th and 90th percentiles were calculated for the intraocular pressure values. RESULTS: Fifty preterm infants with a mean gestational age of 29.7±1.6 weeks and a mean birth weight of 1,127.7±222.7 g were evaluated. The mean intraocular pressure for the entire cohort considering both eyes was 14.9±4.5 mmHg, and 13.5% of all recorded intraocular pressure values were greater than 20 mmHg. The analysis revealed a mean reduction in the intraocular pressure of 0.29 mmHg for each increase in postconceptional age (p = 0.047; 95% CI: −0.58 to −0.0035). The mean intraocular pressure (P10–P90) decreased from 16.3 mmHg (10.52–22.16) at 26.3 weeks to 13.1 mmHg (7.28–18.92) at 37.6 weeks of postconceptional age. CONCLUSIONS: The mean intraocular pressure in very low birth weight preterm infants was 14.9±4.5 mmHg. This value decreased 0.29 mmHg per week as the postconceptional age increased.

Topic liver hypothermia and ischemic preconditioning: a new model of ischemia and reperfusion in rats

PURPOSE Evaluation of the Mean Arterial Pressure (MAP) and body temperature changes in a new model of liver ischemia-reperfusion applying topical Hypothermia and Ischemic Preconditioning (IPC). METHODS Rats (n= 32) were divided in 5 groups: Control (C), Normothermic Ischemia (NI), Ischemic Preconditioning (IPC), Hypothermia 26 degrees C plus IPC (H+IPC) and Hypothermia 26 degrees C (H). MAP and body temperature were recorded at 30 minutes intervals throughout the entire experiment. The study groups underwent 90 minutes partial hepatic ischemia followed by 120 minutes of reperfusion. The median and lateral left lobes were isolated and topical 26 degrees C hypothermia was induced by superfusion of cooled saline solution in H+IPC and H groups. A 10 minutes protocol of ischemia and reperfusion was applied in the IPC and H+IPC groups before the major ischemic insult. RESULTS There was no significant difference in MAP and body temperature means between the groups throughout the experiments. CONCLUSION The present model allows the induction of topical hepatic hypothermia associated or not to IPC. New studies to evaluate the possible synergistic effects of these tools can be reproduced without significant changes in macrohemodynamics and body temperature, or in other words, under stable conditions.

GISTs múltiplos em neurofibromatose tipo 1: diagnóstico incidental em paciente com abdome agudo

BACKGROUND: The literature described an increased incidence of gastrointestinal stromal tumors (GISTs) in patients with neurofibromatosis type 1. These tumors typically occur in the small intestine, and frequently are multiple. Often the behavior of the tumor in this association is more favorable than in sporadic cases. CASE REPORT: Incidental diagnosis of GIST was done in a patient with neurofibromatosis type 1 during treatment for acute abdomen. Trans-operatively was identified a retrocecal perforated appendicitis and a neoplastic mass in the proximal jejunum. The lesion occupied approximately 70% of the circumference of the organ and had no invasion of adjacent structures. Moreover, there were dozens of small nodules scattered throughout the length of the jejunum and ileum. The pathology revealed malignancy consistent with GIST, with moderate degree of atypia, low mitotic index (<5 / 50) and absence of necrosis. In immunohistochemical analysis, the neoplastic cells were positive for CD-34 and CD-117 (c-KIT), and negative for desmin. After surgery, the use of Imatinib chemotherapy was indicated. After a follow-up period of 12 months, the patient showed no signs of recurrence. CONCLUSION: GISTs should be considered in the presence of abdominal mass and neurofibromatosis type 1, affecting mainly small bowel. Sometimes Imatinib can be administered with good results in the control of the disease.