Temperament as a potential predictor of mortality: Evidence from a 41-year prospective study

Psychological factors were hypothesized to influence mortality, in particular, early versus later mortality. To explore the relationship between temperament, a psychological factor, and mortality in a prospective study of 1337 medical students, we constructed a measure portraying three temperament types, using latent class analysis. Death occurred in 113 subjects over 25–41 years of follow-up. In univariate survival analysis, subjects tending to direct tension inward when under stress (Tension-In) had a higher risk of mortality than Tension-Out or Stable types. These associations persisted after adjustment for age, smoking, cholesterol level, and Quetelet Index. The relative risk (RR) of mortality for Tension-In was 1.56 (95% confidence interval, 1.00–2.44) compared with the Stable group. The risk was due entirely to the excess risk in persons under 55 years of age (RR, 2.59; 95% confidence interval, 1.46–4.62); the corresponding risk of death in older persons was 0.66 (0.30–1.48). Thus temperament is a significant risk factor for mortality, in particular, premature death.     

Autosomal location of genes from the conserved mammalian X in the platypus (<Emphasis Type="Italic">Ornithorhynchus anatinus</Emphasis>): implications for mammalian sex chromosome evolution

Mammalian sex chromosomes evolved from an ancient autosomal pair. Mapping of human X- and Y-borne genes in distantly related mammals and non-mammalian vertebrates has proved valuable to help deduce the evolution of this unique part of the genome. The platypus, a monotreme mammal distantly related to eutherians and marsupials, has an extraordinary sex chromosome system comprising five X and five Y chromosomes that form a translocation chain at male meiosis. The largest X chromosome (X₁), which lies at one end of the chain, has considerable homology to the human X. Using comparative mapping and the emerging chicken database, we demonstrate that part of the therian X chromosome, previously thought to be conserved across all mammals, was lost from the platypus X₁ to an autosome. This region included genes flanking the XIST locus, and also genes with Y-linked homologues that are important to male reproduction in therians. Since these genes lie on the X in marsupials and eutherians, and also on the homologous region of chicken chromosome 4, this represents a loss from the monotreme X rather than an additional evolutionary stratum of the human X.     

Construction of a highly enriched marsupial Y chromosome-specific BAC sub-library using isolated Y chromosomes

The Y chromosome is perhaps the most interesting element of the mammalian genome but comparative analysis of the Y chromosome has been impeded by the difficulty of assembling a shotgun sequence of the Y. BAC-based sequencing has been successful for the human and chimpanzee Y but is difficult to do efficiently for an atypical mammalian model species (Skaletsky et al. 2003, Kuroki et al. 2006). We show how Y-specific sub-libraries can be efficiently constructed using DNA amplified from microdissected or flow-sorted Y chromosomes. A Bacterial Artificial Chromosome (BAC) library was constructed from the model marsupial, the tammar wallaby (Macropus eugenii). We screened this library for Y chromosome-derived BAC clones using DNA from both a microdissected Y chromosome and a flow-sorted Y chromosome in order to create a Y chromosome-specific sub-library. We expected that the tammar wallaby Y chromosome should detect ∼100 clones from the 2.2 times redundant library. The microdissected Y DNA detected 85 clones, 82% of which mapped to the Y chromosome and the flow-sorted Y DNA detected 71 clones, 48% of which mapped to the Y chromosome. Overall, this represented a ∼330-fold enrichment for Y chromosome clones. This presents an ideal method for the creation of highly enriched chromosome-specific sub-libraries suitable for BAC-based sequencing of the Y chromosome of any mammalian species.     

Modulation and function of caspase pathways in B lymphocytes

Summary:  During their development, B-lineage cells are selected to mature, to die, to divide, or to survive and wait, ready to respond to external signals. The homeostatic balance between growth, death, and survival is mediated by signaling pathways through the B-cell antigen receptor (BCR) complex, cytokine and chemokine receptors or cell–cell coreceptor interactions. The BCR complex is a master regulator essential at key checkpoints during development. These checkpoints involve various processes, including negative selection (deletion), anergy, receptor editing, and positive selection. Without BCRs or downstream BCR-signaling components, B-lineage cells arrest during development. Removal of BCRs from mature B cells leads to their death. Here, we discuss signaling pathways in B cells that activate members of the caspase family of cysteine proteases. In some B-cell subsets, BCR signaling activates caspases, which in turn induce a program leading to cell death. However, in other contexts, caspases are involved in the proliferation of B cells. The outcome depends in part on the presence or absence of modifiers that affect signaling thresholds and on which caspases are activated. These mechanisms allow the coordinated regulation of proliferation and apoptosis that is essential for lymphoid homeostasis.     

Murine lupus nephritis: effect of azathioprine on glomerular permeability and localization of immunoreactants.

We investigated the effect of azathioprine on glomerular permeability and deposition of immunoreactants in NZB/W mice. Glomerular permeability, assessed by proteins excreted in the urine and by a molecular probe of anionic sites of the basement membrane, underwent negligible changes, in comparison to pre-treatment findings, and deposits of immunoreactants were largely mesangial and were decreased overall. Therapy with azathioprine preserved glomerular structure and function by decreasing the amount of immunoreactants, by inducing a preferential mesangial localization of immunoreactants, and, possibly, by interfering with factors that favor the deposition of immunoreactants in the glomerular capillary wall.     

Clinical Benchmark for Gastric Stapling Procedures

To help answer the call to cut costs of surgical care, hospitals and physicians have joined to compare methods of care for the more common Diagnosis Related Group (DRG) diagnoses to form a Benchmark. Since many bariatric surgeons are the only ones performing this surgery in their primary hospitals, they do not have two or more surgical routines for comparison. This presentation compares data for the preoperative work-up, operating-room, and methods of postoperative care used by 29 members of the American Society for Bariatric Surgery (ASBS). There was representation of both academic and private surgeons and hospitals. To target areas for possible savings, the hospital bills of 16 patients without complication were compared. The synthesis of this information revealed significant differences in the extent and cost of preoperative work-up, antibiotic coverage, other postoperative care, and length of stay. These differences are examined under the assumption that patient outcome was the same.