Successful term pregnancy after Mustard operation for transposition of the great arteries

Transposition of the great arteries is a complex cardiac malformation with poor prognosis without surgical correction. Since the introduction of surgical procedures such as the intra-auricular reorientation of the venous return (Mustard procedure), an increasing number of patients may reach adulthood and experience pregnancy. Because long-term complications after the Mustard operation include systemic heart failure, arrhythmias, venous return stenosis and pulmonary edema, hemodynamic changes during pregnancy and delivery may potentially engender life-threatening complications in these patients. We report the case of a 24-year-old primigravida who underwent a Mustard procedure at the age of 2 years for transposition of the great vessels, and who carried out a full-term pregnancy. The pregnancy was uneventful until the 34th week, when the woman developed signs of moderate right ventricular failure and frequent episodes of accelerated junctional rhythm. Digitalisation improved symptoms and elicited return to normal sinus rhythm. The patient delivered at term by elective cesarean section, under close hemodynamic monitoring.     

Polarization effect in an epoxy resin at elevated temperatures

The elucidation of a polarization process at elevated temperatures in an epoxy-novolac resin cured by BF₃ complex is made. Measurements of permittivity and dissipation factor with various types of electrodes as well as measurements of potential distribution inside the specimen are described.     

Blockade of CCKB but not CCKA receptors before and after the stress of predator exposure prevents lasting increases in anxiety-like behavior: Implications for anxiety associated with posttraumatic stress disorder.

Lasting increases in anxiety-like behavior (ALB) in rodents in the elevated plus maze have been reported to follow brief (5 min) exposures to a cat. This study examined the role of CCKA and CCKB receptors in lasting increases in ALB following exposure to a cat. Block of CCKB receptors 30 min before and after cat exposure prevented increases in ALB assessed 1 week later in the elevated plus maze. Blocks of CCKA receptors either before or after cat exposure were without effect on increases in ALB measured 1 week later. Changes in activity or exploration could not account for the results. Effects of cat exposure on ALB, startle, and corticosteroid levels have been proposed as a model of affective disorder in posttraumatic stress disorder (PTSD). Implications of these findings for mechanisms of initiation of anxiety in PTSD and posttrauma pharmacological prophylaxis in PTSD are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Shock-wave configuration in air gap on oblique collision of metal plates

With the aid of a 4-frame photorecorder operating with SNEF-4 electron-optical converters, shock waves in the air gap between colliding plates were photographed. We have demonstrated that in the movement of a plate within the gap an oblique shock wave is generated, and that the interaction of this shock wave with the lower plate occurs in the form of simple Mach wave reflection. The Mach wave arm moves faster than the detonation velocity of the explosive by a factor of 1.3.Warsaw. Novosibirsk. Translated from Fizika Goreniya i Vzryva, No. 2, pp. 128–130, March–April, 1991.     

Reduced sarcolemmal dystrophin distribution and upregulation of utrophin in the cardiac and skeletal muscles of CHF-146 dystrophic hamsters

Abnormalities in the dystrophic gene product, dystrophin, have been implicated in initiating the primary membrane defect and excessive intracellular calcium accumulation (EICA), which play fundamental pathogenic roles in hereditary muscular dystrophy (HMD). Two other cytoskeletal proteins, spectrin and utrophin, bear remarkable structural and functional homologies to dystrophin. CHF-146 strain dystrophic hamsters (DH), like patients with Duchenne muscular dystrophy (DMD), die prematurely from cardiopulmonary insufficiency, focal myonecrosis, and progressive degeneration of the cardiac and skeletal muscles with EICA. Although DH present a suitable model for HMD, there are controversies concerning their dystrophin and utrophin status. Using immunocytochemistry and Western blotting, we studied dystrophin, spectrin and utrophin anomalies in the cardiac and skeletal muscles of 6-mo-old male DH. Age- and sex-matched CHF-148 strain albino normal hamsters (NH) served as controls. Sarcolemmal dystrophin staining was much weaker and interruptive in the DH. The densitometric analysis of the immunoblots revealed that dystrophin is reduced in DH by 83% in cardiac muscle (p < 0.0001), and by 50% in skeletal muscle (p < 0.0001). We conclude that sarcolemmal dystrophin distribution is markedly reduced and discontinuous in the cardiac and skeletal muscles of DH, with simultaneous upregulation of utrophin and a varied degree of spectrin labelling. This observation suggests that reduced sarcolemmal dystrophin is associated with membrane hyperpermeability, which leads to progressive muscle degeneration via EICA and segmental necrosis in DH. As in DMD, utrophin appears to play an important compensatory role in hamster dystrophinopathy.     

Assessing the potential to derive air–sea freshwater fluxes from Aquarius‐like observations of surface salinity

A state‐of‐the‐art numerical model is used to investigate the possibility of determining freshwater flux fields from temporal changes in sea‐surface salinity (SSS), a goal of the satellite salinity‐measuring mission, Aquarius/SAC‐D. Because the estimated advective temporal scale is usually longer than the Aquarius/SAC‐D revisit time, the possibility of producing freshwater flux estimates from temporal salinity changes is first examined by using a correlation analysis. For the mean seasonal cycle, the patterns of the correlations between the freshwater fluxes and surface salinity temporal tendencies are mainly zonally oriented, and are highest where the local precipitation is also relatively high. Nonseasonal (deviations from the monthly mean) correlations are highest along mid‐latitude storm tracks and are relatively small in the tropics. The complex correlation patterns presented here suggest that a global retrieval of the difference between evaporation and precipitation (E–P) from salinity changes requires more complex techniques than a simple consideration of a local balance with surface forcing.     

Electrical conductivity of PMMA at linearly increasing temperatures

The temperature dependence of electrical conductivity in poly(methyl methacrylate), representing polar polymers, has been measured at linearly increasing temperatures in the range from -100 to +100°C. The interpretation by superposition of inherent conductivity and polarization processes is discussed.