Cationic amylopectin derivatives as additives for analysis of proteins in capillary electrophoresis.

Positively charged amylopectin, which is a major constituent of cationic starch, was used to modify the inner surface of fused-silica capillaries by addition to the running solution, which was subsequently employed in CE. Capillaries filled with cationic amylopectin derivatives were shown to generate a stable reversed EOF in the investigated range of pH 4-8. Among the additives studied, quaternary ammonium amylopectin derivatives with high amino and low hydroxypropyl groups showed fast electroosmotic mobility and very effectively suppressed the adsorption of proteins. The run-to-run and batch-to-batch repeatability of the procedures were satisfactory with RSDs of 0.5% and 2.4%, respectively. A basic protein, alpha-chymotrypsinogen, migrated within 6 min and the theoretical plate number of it reached 560 000 plates/m.

Cationic starch derivatives as dynamic coating additives for protein analysis in capillary electrophoresis.

Positively charged starch derivatives were used to modify the inner surface of fused-silica capillaries by addition to running buffer, which were subsequently employed in capillary electrophoresis (CE). Capillaries coated with the cationic starch derivatives were shown to generate a stable, reversed electroosmotic flow (EOF) in the investigated pH range of 3-9. The presented coating procedure was fast, based on a simple rinsing protocol where the polymer created a physically adsorbed, cationic polymer layer. Among the additives studied, a quaternary ammonium starch derivative showed a fast EOF mobility and effectively suppressed the adsorption of proteins. The intra- and inter-day reproducibility of the coating referring to the EOF mobility were satisfactory with relative standard deviation (RSD) of 0.27 and 1.67%, respectively. The coating enabled separation of some protein mixtures including basic proteins within l3 min with efficiencies up to 280,000 plates/m. In addition, this cationic starch derivative possessed a good solubility (about 100mg/mL), and it does not significantly contribute to the background adsorption in the UV region of 190-400 nm.

Analysis of amino acids and proteins using a poly(methyl methacrylate) microfluidic system.

Plastic microchips are very promising analytical devices for the high-speed analysis of biological compounds. However, due to its hydrophobicity, their surface strongly interacts with nonpolar analytes or species containing hydrophobic domains, resulting in a significant uncontrolled adsorption on the channel walls. This paper describes the migration of fluorescence-labeled amino acids and proteins using the poly(methyl methacrylate) microchip. A cationic starch derivative significantly decreases the adsorption of analytes on the channel walls. The migration time of the analytes was related to their molecular weight and net charge or pI of the analytes. FITC-BSA migrated within 2 min, and the theoretical plate number of the peak reached 480,000 plates/m. Furthermore, proteins with a wide range of pI values and molecular weights migrated within 1 min using the microchip.

A proposal of new therapeutic strategy for antenatally diagnosed congenital diaphragmatic hernia.

PURPOSE: The prognosis of antenatally diagnosed congenital diaphragmatic hernia (ADCDH) is still very poor despite of innovation of various therapeutics. The authors reviewed their new therapeutic strategy of ADCDH from a viewpoint of cardiologic function. METHODS: The cardiac function in 19 cases of ADCDH was reviewed. The patients, at the age of 0 days, were divided into 2 groups, PG (+) and PG (-), according to the requirement of prostaglandin E1 (PGE1) to attenuate pulmonary hypertension. The left ventricular (LV) end-diastolic dimension (LV diastolic diameter index [LVDI]) and bilateral pulmonary arterial diameters (total pulmonary artery index [TPAI]) were measured on days 0 and 2. RESULT: Only 1 patient died of cardiac or respiratory failure, and the survivors' postoperative course was uneventful. Eleven patients needed inhalation of nitric oxide (NO), and in 9 of those, PGE1 was administered. The LVDI and TPAI of day 0 in PG (+) were significantly smaller than those in PG (-) and the controls. The LVDI increased from postnatal day 0 to day 2 in both PG (+) and PG (-). Although the LV was too small to output enough volume, the right ventricle successfully compensated for the low output through the ductus arteriosus, kept patent by NO and PGE1. CONCLUSION: For ADCDH with sever pulmonary hypertension, keeping patent ductus arteriosus with NO and PGE1 plays a critical role in obtaining excellent clinical outcome. Thus, the authors proposed a new therapeutic strategy for ADCDH based on a circulatory management.

Left and right ventricular function in fetal tetralogy of Fallot with absent pulmonary valve.

Tetralogy of Fallot with absent pulmonary valve (TOF/APV) is a rare form of congenital heart disease with a high risk of perinatal mortality, particularly when diagnosed before birth. We aimed to assess whether global left and right ventricular function in fetal TOF/APV, using the Tei index, correlate with outcome. We reviewed the fetal echocardiogram and clinical outcome of eight fetuses diagnosed with TOF/APV. Of the eight cases, four developed cardiovascular compromise, leading to intrauterine death in two fetuses and neonatal demise in two fetuses, and four fetuses survived the neonatal period. The right ventricular (RV) Tei index was significantly greater and the left ventricular (LV) Tei index tended to be greater in nonsurvivors compared with survivors with TOF/APV (RV Tei, 0.90 +/- 0.17 versus 0.30 +/- 0.28, p < 0.05; LV Tei, 0.97 +/- 0.42 versus 0.54 +/- 0.21). The global LV and RV function can be affected in TOF/APV. Furthermore, more severe pulmonary insufficiency and worse biventricular function as assessed by Tei index likely contribute to the high perinatal mortality associated with this disease.

Cationic starch derivatives as dynamic coating additives for analysis of amino acids and peptides using poly(methyl methacrylate) microfluidic devices.

Plastic microchips are very promising analytical devices because they are less fragile and are suitable for mass production. However, due to their hydrophobicity, the surface strongly interacts with nonpolar analytes or species containing hydrophobic domains, resulting in significant uncontrolled adsorption on channel walls. This paper describes the poly(methyl methacrylate) surface treatment by dynamic coating additives that considerably decreases adsorption of analytes to channel walls. Among the additives studied, quaternary ammonium starch derivatives suppressed the adsorption of fluorescently labeled amino acids and peptides most effectively. The effect was valid over the wide pH range from 2.5 to 8.0. Using a 10 mM phosphate buffer (pH 7.0) with 3% (w/v) quaternary ammonium starch as the running buffer, Asp and Glu, respectively, migrated at 54.6 and 57.6 s with efficiencies of 380 000 and 370 000 plates/m. In addition, this cationic starch derivative was found to possess good solubility and low viscosity.

Successful transcatheter coil embolization of coronary artery to left ventricular fistula associated with absent pulmonary valve with tricuspid atresia in early infancy.

Transcatheter coil embolization for coronary artery to left ventricular fistula was successfully performed in a neonate. At 30 weeks' gestation, fetal echocardiography showed a hypoplastic right ventricle with intact ventricular septum, absent pulmonary valve, tricuspid atresia, and marked distension of the right coronary artery. After birth, the neonate had congestive heart failure and the electrocardiogram showed myocardial ischemic changes in the left ventricular area. Aortography showed a dilated right coronary artery arising from the ascending aorta and draining into the left ventricle. Transcatheter coil embolization was carried out on the 9th day after birth. Since the procedure, no myocardial ischemic changes have been detected. Transcatheter coil embolization is a useful therapy for coronary artery fistula associated with myocardial ischemia.

Management of univentricular heart with systemic ventricular outflow obstruction by pulmonary artery banding and Damus-Kaye-Stansel operation.

BACKGROUND: Some patients with univentricular hearts who are candidates for Fontan operation may develop ventricular outflow tract obstruction after pulmonary artery banding (PAB) or Fontan. However, the indication for Damus-Kaye-Stansel (DKS) operation for these patients has not been clear. To clarify the indication, the changes in the diameter of ventricular outflow tract and the feasibility of DKS operation before or with Fontan were investigated. METHODS: Among the patients with univentricular heart who underwent PAB, 21 patients had probable ventricular outflow obstruction with an aorta arising from the morphologic right ventricle. Diameter of ventricular outflow tract was measured before and after PAB, Glenn, and Fontan operations with or without DKS, and indexed by normal value (%VOT). RESULTS: Six patients died after PAB. In the surviving 15 patients, %VOT decreased significantly from 103% (median, range 75%-153%) to 75% (range 52%-153%) after PAB. Four with very small %VOT (52% to 63%) after PAB needed DKS with bidirectional Glenn or central shunt operation, and 5 with moderately small %VOT (67% to 109%) after PAB needed DKS concomitantly with Fontan. A patient with %VOT of 117% before Fontan required DKS after Fontan. A patient with %VOT of 153% underwent Fontan without DKS and obstruction did not develop after Fontan. The remaining 4 patients were under consideration for Glenn or Fontan operation. CONCLUSIONS: The diameter of the ventricular outflow tract decreased after PAB and Fontan operations. DKS operations might be indicated before Fontan if the indexed diameter of ventricular outflow tract after PAB was below 70% and concomitantly with Fontan if it was below 120%.

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.

A girl with 1p36 deletion syndrome and congenital fiber type disproportion myopathy.

Chromosome 1p36 deletion syndrome is characterized by hypotonia, moderate to severe developmental and growth retardation, and characteristic craniofacial dysmorphism. Muscle hypotonia and delayed motor development are almost constant features of the syndrome. We report a 4-year-old Japanese girl with 1p36 deletion syndrome whose muscle pathology showed congenital fiber type disproportion (CFTD) myopathy. This is the first case report of 1p36 deletion associated with CFTD. This association may indicate that one of the CFTD loci is located at 1p36. Ski proto-oncogene -/- mice have phenotypes that resemble some of the features observed in patients with 1p36 deletion syndrome. Because fluorescent in situ hybridization analysis revealed that the human SKI gene is deleted in our patient, some genes in 1p36, including SKI proto-oncogene, may be involved in muscle hypotonia and delayed motor development in this syndrome.