Surgical management of congenital cardiac defects in neonates and young infants born with extremely low weight

Surgical treatment of cardiac defects in infants born with extremely low weight is sometimes required during the neonatal period. Optimal timing of these operations has yet to be clarified. With this in mind, we reviewed our experience of surgical treatment for 29 infants born with extremely low weight between 1994 and 2001. The main surgical procedures were ligation of a patent arterial duct in 26, a Brock procedure in 2, and ligation of an aorto-pulmonary window in 1 infant. The age at operation ranged from 5 to 57 days, with a median of 30 days, and weighed from 506 to 902 g, with a median of 710 g. There were no deaths. For the 2 infants undergoing the Brock procedure, the reduced systemic blood flow also necessitated closure of the arterial duct. For almost all the 26 infants with a patent arterial duct, indomethacin was given as the initial therapy, but the duct had not closed completely. Increased symptomatology just before the operation due to reduced systemic blood flow, such as decreased cerebral blood flow, decreased urine output, and intestinal ischemia, mandated the earlier surgical ligation (r = -0.576, p = 0.004). The youngest infant needed an infusion of catecholamines perioperatively to maintain stable hemodynamic conditions (r = 0.554, p = 0.003). In 4 infants, including the youngest 2, steroids were administered intravenously just after the ligation. Our results suggest that reduced systemic blood flow is the main indication of surgical repair in infants born with extremely low weight. Even for one in whom the supply of pulmonary blood is dependent on the arterial duct, early reconstruction of the pulmonary arterial pathways, using the Brock procedure, followed by ligation of the duct, is required. Acute adrenal insufficiency should not be overlooked just after the surgery, particularly in the youngest patients.     

Preconditioning with hyperbaric oxygen and hyperoxia induces tolerance against spinal cord ischemia in rabbits

BACKGROUND: The aim of this study was to determine if the ischemic tolerance could be induced in the spinal cord by pretreatment with hyperbaric oxygen (HBO) and what components of HBO (hyperoxia, hyperbaricity, and combination of these two) were critical in the induction of tolerance against ischemic injury. METHODS: In experiment 1, 21 rabbits were randomly assigned to one of three groups (n = 7 each): animals in the control group received no HBO before spinal cord ischemia; animals in the HBO-1 and HBO-2 groups received HBO (2.5 atmosphere absolute [ATA], 100% O2) pretreatment 1 h/day for 3 and 5 days before ischemia, respectively. In experiment 2, 48 rabbits were randomly assigned to one of four groups (n = 12 each): the control group received no HBO (21% O2, 1 ATA, 1 h/day, 5 days) before spinal cord ischemia; the HB group received 1-h treatment in 21% O2 at 2.5 ATA each day for 5 days; the HO group received 1-h treatment in 100% oxygen at 1 ATA each day for 5 days; and the HBO group received HBO (2.5 ATA, 100% O2) treatment 1 h/day for 5 days. Twenty-four hours after the last treatment, spinal cord ischemia was induced by an infrarenal aorta clamping for 20 min. Forty-eight hours after reperfusion, hind-limb motor function and histopathology of the spinal cord were examined in a blinded fashion. RESULTS: In experiment 1, the neurologic outcome in the HBO-2 group was better than that of the control group (P = 0.004). The number of normal neurons in the anterior spinal cord in the HBO-2 group was more than that of the control group (P = 0.021). In experiment 2, the neurologic and histopathologic outcomes in the HBO group were better than that of the control group (P < 0.01). The histopathologic outcome in the HO group was better than that in the control group (P < 0.05). CONCLUSIONS: Serial exposure to high oxygen tension induced ischemic tolerance in spinal cord of rabbits. Simple hyperbaricity (2.5 ATA, 21% O2) did not induce ischemic tolerance.     

The effects of different environmental education programs on the environmental behavior of seventh-grade students and related factors

This study used random allocation to separate out groups of students from four Taipei junior high schools, each of which underwent a different environmental-education program, in order to examine the effects of such programs on students' environmental behavior and related factors. Results indicate that Taiwanese junior high schools should coordinate the teaching of environmental programs with other school activities to obtain the most ideal results.     

Laser capture microdissection and microarray expression analysis of lung adenocarcinoma reveals tobacco smoking- and prognosis-related molecular profiles

Recent expression profile analyses revealed that lung adenocarcinomas can be divided into several subgroups with diverse pathological features. Because cellular heterogeneity of tumors can confound these analyses, we used laser capture microdissection and microarray expression analysis to characterize the molecular profiles of lung adenocarcinomas. We found 45 genes delineating smokers and nonsmokers that were located at chromosomal loci frequently altered in non-small cell lung cancers, and 27 genes, which were differentially expressed between survivors and nonsurvivors 5 years after surgery. These results are consistent with the hypothesis that the abnormal expression of genes involved in maintaining the mitotic spindle checkpoint and genomic stability, e.g., hBUB3, hZW10, and APC2, contribute to the molecular pathogenesis and tumor progression of tobacco smoke-induced adenocarcinoma of the lung.     

Intermediate dose pre-operative irradiation for carcinoma of the rectum

BACKGROUND: To assess the locoregional control, survival and toxicities of combined intermediate-dose pre-operative irradiation and surgery for rectal cancer patients. MATERIALS AND METHODS: Forty-two patients with adenocarcinoma of the rectum underwent intermediate-dose pre-operative radiotherapy. The median age was 58 years. the prescribed dose was 30.6 Gy to the whole pelvis, while a boost of 4 x 3 Gy to the primary tumor was added. The calculated linear-quadratic dose was 52 Gy. RESULTS: Failure as a first site was pelvic in 2 and distant in 11. The crude pelvic failure rate was 9.5%. The 3- and 5-year overall survival was 75% and 63%, respectively. Pre-operative radiotherapy was well-tolerated by all. No anastomotic breakdown was seen. Nor was any death attributable to any adverse effects of the treatment. CONCLUSION: The present results suggested that pre-operative intermediate-dose radiotherapy is effective in preventing pelvic recurrence in rectal cancer patients with acceptable toxicities.     

Detection of hypervascular hepatocellular carcinoma by dynamic magnetic resonance imaging with double-echo chemical shift in-phase and opposed-phase gradient echo technique: comparison with dynamic helical computed tomography imaging with double arterial phase

PURPOSE: The technique of double-echo chemical shift gradient echo magnetic resonance imaging (MRI) with the fast low-angle shot (double-echo FLASH) sequence provides in-phase and opposed-phase images in a single breath hold. The purpose of this study was to evaluate the efficacy of dynamic MRI with double-echo FLASH imaging for the detection of hypervascular hepatocellular carcinoma by comparing it with dynamic helical computed tomography (CT) imaging with double arterial phase. MATERIALS AND METHODS: Twenty-nine patients with 67 hypervascular hepatocellular carcinoma nodules who underwent both dynamic MRI with double-echo FLASH imaging (repetition time/echo time/flip angle: 160/3.6, 7.0/80 degrees ) and dynamic helical CT imaging with double arterial phase were enrolled in the study. For dynamic MRI, precontrast, arterial, portal venous, and equilibrium phase images were obtained before and approximately 19, 60, and 120 seconds, respectively, after intravenous injection of 0.1 mmol/kg of gadopentetate dimeglumine at a rate of 2 ml/s. For dynamic CT imaging, quadraphase images, including early arterial, late arterial, portal venous, and equilibrium phases, were obtained serially approximately 20, 30, 70, and 180 seconds, respectively, after intravenous administration of 2 ml/kg of 300 mgI/ml of nonionic contrast medium at a rate of 5 ml/s. Three masked observers independently interpreted images obtained with each technique in random order, separately and without patient identifiers. Sensitivity and positive predictive values as well as the area below the alternative-free response receiver operating characteristic curve (Az) for each imaging technique were calculated and compared statistically. RESULTS: Mean sensitivity and positive predictive values of MRI for hypervascular hepatocellular carcinoma were 48% and 94%, respectively, and those of CT imaging were 47% and 91%, respectively. In 11 (38%) of the 29 patients, at least one observer judged dynamic MRI to be superior, whereas in 5 patients (17%), dynamic CT was judged to be superior. There was no significant difference in the sensitivity and positive predictive values between these techniques (p > 0.05). There was no significant difference either in mean Az values between CT (0.55) and MRI (0.57) (p = 0.61). CONCLUSION: Dynamic MRI with double-echo FLASH imaging can detect hypervascular hepatocellular carcinoma as well as dynamic helical CT imaging with double arterial phase.     

High dose rate endovascular brachytherapy in aorto-iliac lesion for the prevention of restenosis

This study examined the applicability of endovascular brachytherapy to larger del arteries such as the abdominal aorta and iliac artery. Endovascular brachytherapy using an Ir-192 HDR source was administered 11 times to nine patients who had undergone percutaneous transluminal angioplasty (PTA) between 1995 and 1999. The follow-up lasted 13 to 55 months after treatment (median, 24 months). Eight of the 11 lesions have been controlled so far. Although one case developed thrombus inside the stent five months later, recanalization was achieved by means of retreatment. One patient who underwent low-dose irradiation (6 Gy) without stent implantation showed restenosis five months after treatment. We used a centering catheter that did not block the blood stream for exact centering of the radiation source in larger vessels such as the abdominal aorta. Although endovascular brachytherapy is a promising and safe procedure, careful follow-up is needed to detect untoward reactions such as thrombosis.