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A letter to the editor is presented in response to the article "Inadvertent catheterisation of a partial anomalous pulmonary venous channel during central venous cannulation," by C. J. Cheng, B. L. Lim and B. S. Tan in the 2002 issue.

The article presents reply of authors on comments made by researcher Kai Ma and colleagues on their article "17-year Experience in Surgical Management of Congenitally Corrected Transposition of the Great Arteries: A Single-Centre's Experience."

Objectives To assess the quality of life (QoL) in adults with congenital heart disease (ACHD) and to explore the sex-related differences and biopsychosocial determinants in an Asian cohort. Design Prospective cross-sectional clinical study. Setting One tertiary medical centre in Taiwan. Patients and methods The QoL of ACHD (≥20⇔…years) was investigated using the Taiwanese version of the QoL questionnaire designed by the WHO, which assesses four domains of QoL (physical, psychological, social and environmental). Personality, psychological distress and family support were assessed using the Maudsley Personality Inventory, Brief Symptom Rating Scale, and the Family APGAR score, respectively. Results A total of 289 patients (age 33.2±10.6⇔…years; 36% men) were studied. ACHD women had significantly lower QoL scores in the physical and psychological domains compared to the age-matched general population, whereas no differences were observed between ACHD men and the general population. Multivariate analysis showed that female gender was associated with poorer physical QoL; the sex difference in the psychological QoL was mediated by psychological distress. Interaction analysis showed that the effect of family support on the psychological domain of QoL may be different by sex. The determinants of QoL varied between different domains. Extroversion personality trait, psychological distress and family support were common determinants of most domains of QoL. Conclusions In ACHD, female gender was associated with poor physical and psychological QoL. The common denominators for QoL were primarily personality trait, psychological distress and family support, but not disease severity. [ABSTRACT FROM AUTHOR]

The article focuses on processive cleavage of substrate at individual proteolytic active sites of the Lon protease complex. Topics include the Lon protease is the prototype of a family of proteolytic machines with adenosine triphosphatase modules built into a substrate degradation chamber, and the Lon is known to degrade protein substrates in a processive fashion, cutting a protein chain processively into small peptides before commencing cleavages of another protein chain.

The Lon AAA+ (adenosine triphosphatases associated with diverse cellular activities) protease (LonA) converts ATP-fuelled conformational changes into sufficient mechanical force to drive translocation of a substrate into a hexameric proteolytic chamber. To understand the structural basis for the substrate translocation process, we determined the cryoelectron microscopy (cryo-EM) structure of Meiothermus taiwanensis LonA (MtaLonA) in a substrate-engaged state at 3.6 A resolution. Our data indicate that substrate interactions are mediated by the dual pore loops of the ATPase domains, organized in spiral staircase arrangement from four consecutive protomers in different ATP-binding and hydrolysis states. However, a closed AAA+ ring is maintained by two disengaged ADP-bound protomers transiting between the lowest and highest position. This structure reveals a processive rotary translocation mechanism mediated by LonA-specific nucleo-tide-dependent allosteric coordination among the ATPase domains, which is induced by substrate binding. [ABSTRACT FROM AUTHOR]

Cobra cardiotoxins (CTX) are a family of three-fingered basic polypeptides known to interact with diverse targets such as heparan sulfates, sulfatides, and integrins on cell surfaces. After CTX bind to the membrane surface, they are internalized to intracellular space and exert their cytotoxicity via an unknown mechanism. By the combined in vitro kinetic binding, three-dimensional x-ray structure determination, and cell biology studies on the naturally abundant CTX homologues from the Taiwanese cobra, we showed that slight variations on the spatial distribution of positively charged or hydrophobic domains among CTX A2, A3, and A4 could lead to significant changes in their endocytotic pathways and action mechanisms via distinct sulfated glycoconjugate-mediated processes. The intracellular locations of these structurally similar CTX after internalization are shown to vary between the mitochondria and lysosomes via either dynamin2-dependent or -independent processes with distinct membrane cholesterol sensitivity. Evidence is presented to suggest that the shifting between the sulfated glycoconjugates as distinct targets of CTX A2, A3, and A4 might play roles in the co-evolutionary arms race between venomous snake toxins to cope with different membrane repair mechanisms at the cellular levels. The sensitivity of endocytotic routes to the spatial distribution of positively charged or hydrophobic domains may provide an explanation for the diverse endocytosis pathways of other cell-penetrating basic polypeptides. [ABSTRACT FROM AUTHOR]

Demonstrates the effectiveness of electron beam computed tomography in diagnosing heterotaxy syndrome associated with congenital heart disease in children. Visceral, bronchopulmonary and cardiac anomalies; Bilateral trifurcated bronchi; Absence of a spleen; Bilateral bifurcated bronchi; Polysplenia; Lobulated single spleen.