The conserved asparagine and arginine are essential for catalysis of mammalian adenylyl cyclase

Mammalian adenylyl cyclases have two homologous cytoplasmic domains (C1 and C2), and both domains are required for the high enzymatic activity. Mutational and genetic analyses of type I and soluble adenylyl cyclases suggest that the C2 domain is catalytically active and the C1 domain is not; the role of the C1 domain is to promote the catalytic activity of the C2 domain. Two amino acid residues, Asn-1025 and Arg-1029 of type II adenylyl cyclase, are conserved among the C2 domains, but not among the C1 domains, of adenylyl cyclases with 12 putative transmembrane helices. Mutations at each amino acid residue alone result in a 30-100-fold reduction in Kcat of adenylyl cyclase. However, the same mutations do not affect the Km for ATP, the half-maximal concentration (EC50) for the C2 domain of type II adenylyl cyclase to associate with the C1 domain of type I adenylyl cyclase and achieve maximal enzyme activity, or the EC50 for forskolin to maximally activate enzyme activity with or without Gsalpha. This indicates that the mutations at these two residues do not cause gross structural alteration. Thus, these two conserved amino acid residues appear to be crucial for catalysis, and their absence from the C1 domains may account for its lack of catalytic activity. Mutations at both amino acid residues together result in a 3,000-fold reduction in Kcat of adenylyl cyclase, suggesting that these two residues have additive effects in catalysis. A second site suppressor of the Asn-1025 to Ser mutant protein has been isolated. This suppressor has 17-fold higher activity than the mutant and has a Pro-1015 to Ser mutation.     

Hospital readmission after trauma: an analysis of outpatient complications

BACKGROUND: Outpatient complications leading to hospital readmission after hospitalization for trauma have not been examined. METHODS: A retrospective chart review of all trauma victims admitted to a Level 1 trauma center from January of 1990 to January of 1995 was performed to characterize patients who required readmission after hospitalization for trauma. Risk factors for readmission were determined by stepwise regression analysis. RESULTS: Of 15,463 trauma admissions, 209 patients (1.4%) required readmission, 84% within 30 days, 71% within 14 days. Reasons for readmission included wound (29%), abdominal (29%), pulmonary (18%), and thromboembolic (19%) complications. Fifty of the patients (24%) readmitted with a complication required an operation. Risk factors for readmission included: operation during first hospitalization (p < 0.0001), penetrating injury (p = 0.0001), and advanced age (p = 0.0001). Injury Severity Score, length of hospitalization, and gender were not independent predictors of readmission. CONCLUSIONS: Outpatient complications leading to readmission after hospitalization for trauma are not common; however, many are serious and require operative intervention. Because most complications were identified by the second week after discharge, outpatient follow-up visits should be scheduled within 7 to 14 days. Based on our findings, we recommend protocols be established to ensure follow-up for trauma patients, especially those who have had an operation, were victims of penetrating injury, or those > 65 years of age.     

Wing scale microstructures and nanostructures in butterflies − natural photonic crystals

The aim of our study was to investigate the correlation between structural colour and scale morphology in butterflies. Detailed correlations between blue colour and structure were investigated in three lycaenid subfamilies, which represent a monophylum in the butterfly family Lycaenidae (Lepidoptera): the Coppers (Lycaeninae), the Hairstreaks (Theclinae) and the Blues (Polyommatinae). Complex investigations such as spectral measurements and characterization by means of light microscopy, scanning electron microscopy and transmission electron microscopy enabled us to demonstrate that: (i) a wide array of nanostructures generate blue colours; (ii) monophyletic groups use qualitatively similar structures; and (iii) the hue of the blue colour is characteristic for the microstructure and nanostructure of the body of the scales.     

The effect of sphenopalatine postganglionic neurotomy on the alteration of local cerebral blood flow of normotensive and hypertensive rats in acute cold stress

The Temperament and Character Inventory (TCI) is a self-report personality questionnaire based on Cloninger's psychobiological model of personality, which accounts for both normal and abnormal variation in the two major components of personality, temperament and character. Normative data for the Swedish TCI based on a representative Swedish sample of 1,300 adults are presented, and the psychometric properties of the questionnaire are discussed. The structure of the Swedish version replicates the American version well for the means, distribution of scores, and relationships within the between scales and subscales. Further, the Swedish inventory had a reliable factor structure and test-retest performance. The results of this study confirm the theory of temperament and character as a seven-factor model of personality.     

Small cell neuroendocrine carcinoma of the urinary bladder. A clinicopathologic study with emphasis on cytologic features

In mice, peritoneal B cells are composed of a unique B-1 cell population which can repopulate the intestinal lamina propria with IgA-producing cells, as well as contribute to the majority of serum IgM. In this study, peritoneal lymphocytes from patients starting continuous ambulatory peritoneal dialysis (CAPD) and from women undergoing bilateral tubal ligation (BTL) were analysed for the presence of a B-1 cell population as well as the expression of potential homing receptors. Up to 63% of the peritoneal B cells express surface antigen CD5, and most peritoneal lymphocytes express the mucosal homing receptors, alpha4 beta7 and alphaE beta7. When analysing serial samples collected from patients from the beginning of dialysis to 1 year, no marked changes were observed in serum or salivary immunoglobulin levels, although the peritoneal lymphocyte population was reduced by 50%. These data suggest that the phenotype of human peritoneal B-1 cells is similar to that of mice, but the contributions to the immune system may differ.     

A new low density lipoprotein receptor related protein, LRP5, is expressed in hepatocytes and adrenal cortex, and recognizes apolipoprotein E

The isolation and characterization of rabbit and human cDNAs revealed a new low density lipoprotein receptor (LDLR)-related protein (LRP) designated as LRP5. Human LRP5 cDNA encodes a 1, 616-amino acid type I membrane-like protein with three ligand binding repeats in its extracellular region. LDLR-deficient cells transduced by recombinant adenovirus containing human LRP5 exhibited increased binding of apolipoprotein E (apoE)-enriched beta-migrating very low density lipoprotein. Northern blotting and in situ hybridization revealed a high level of LRP5 expression in hepatocytes and the adrenal gland cortex. In LDLR-deficient Watanabe heritable hyperlipidemic rabbits, LRP5 mRNA was increased in the liver and accumulated in cholesterol-laden foam cells of atherosclerotic lesions.