Giant right atrial myxoma leading to cardiac arrest in an infant.

We present the case of a three-month-old infant with a giant right atrial myxoma obstructing the tricuspid valve, who following haemodynamic deterioration and cardiac arrest, was operated upon as an emergency. On echocardiogram, there was a mass attached to the tricuspid annulus, in close proximity to the septal leaflet, with dimensions of 16.6 × 12.5 mm. The mass was prolapsing through the tricuspid valve into the right ventricle and obstructing the inflow. While preparing for surgery, cardiac arrest occurred, so the patient underwent an emergency operation under cardiopulmonary resuscitation. The mass was excised without damaging the tricuspid valve and the conduction system. Histologically, the mass consisted of a myxoid matrix with scatted globoid and star-shaped myxoma cells. The patient stayed 15 days in the intensive care unit and was discharged home on the 20th day postoperatively. Although accepted as a benign tumour, a myxoma can display an aggressive clinical course in infants. In centres where cardiac operations cannot be performed, these patients need to be transferred to cardiac centres as soon as possible. Whatever the clinical presentation, we advocate immediate surgical extirpation of the tumour in order to avoid any unpredictable consequences in its clinical course.

Biventricular involvement in a Turkish boy with palmoplantar hyperkeratosis and curly hair, an unusual presentation of Naxos-Carvajal syndrome.

Naxos disease is an autosomal recessively inherited familial syndrome characterized by woolly hair, palmoplantar keratoderma and a cell adhesion cardiomyopathy, especially arrhythmogenic right ventricular dysplasia (ARVD). Carvajal syndrome is a variant of Naxos disease in which curly or woolly hair, biventricular--predominantly left ventricular involvement were seen. Mutations in genes encoding the cell adhesion proteins like plakoglobin and desmoplakin were related with these syndromes. We report a 17-year-old boy and his family findings with curly hair, palmoplantar hyperkeratosis, ARVD and left ventricular involvement. The family was of Arabic origin, and a third-degree consanguinity was reported between the parents. They are from east part of Turkey and there were no relatives from Cyclades Island (Greece). Patient's younger brother had ARVD without cutaneous manifestations of the syndrome and his grand father had mild ARVD, curly hair and palmoplantar hyperkeratosis.

Maternal colonisation with group B streptococcus and effectiveness of a culture-based protocol to prevent early-onset neonatal sepsis.

This study was conducted to find out the group B streptococcus colonisation of pregnant women in Kocaeli, Turkey. A culture plus individualised high-risk-based antibiotic prophylaxis was compared with high-risk-based approach alone. The screening of women was performed via vaginal and anal cultures for group B streptococcus (GBS). The maternal GBS colonisation rate was found to be 6.5%. All colonised women or preterm labours with unavailable culture results until delivery received prophylactic antibiotics. Neonatal colonisation rate and early-onset neonatal sepsis due to GBS was 1/200. The unscreened 900 women received prophylactic antibiotics due to a risk factor-based approach. The neonatal colonisation rate was 17/900 (p = 0.1), and the rate of early-onset neonatal sepsis was 3/900 (p = 0.6). A culture plus individualised high-risk-based antibiotic prophylaxis provided an insignificant change in neonatal colonisation and early-onset neonatal sepsis with GBS when compared with high-risk-based approach alone.

Novel kinetics of mammalian glutathione synthetase: characterization of gamma-glutamyl substrate cooperative binding.

Glutathione (GSH) synthetase [L-gamma-glutamyl-L-cysteinyl:glycine ligase (ADP-forming), EC 6.3.2.3] catalyzes the final step in GSH biosynthesis. Mammalian glutathione synthetase is a homodimer with each subunit containing an active site. We report the detailed kinetic data for purified recombinant rat glutathione synthetase. It has the highest specific activity (11 micromol/min/mg) reported for any mammalian glutathione synthetase. The apparent K(m) values for ATP and glycine are 37 and 913 microM, respectively. The Lineweaver-Burk double reciprocal plot for gamma-glutamyl substrate binding revealed a departure from linearity indicating cooperative binding. Quantitative analysis of the kinetic results for gamma-glutamyl substrate binding gives a Hill coefficient (h) of 0. 576, which shows the negative cooperativity. Neither ATP, the other substrate involved in forming the enzyme-bound gamma-glutamyl phosphate intermediate, nor glycine, which attacks this intermediate to form GSH, exhibit any cooperativity. The cooperative binding of gamma-glutamyl substrate is not affected by ATP concentration. Thus, mammalian glutathione synthetase is an allosteric enzyme.