D-AKAP2, a novel protein kinase A anchoring protein with a putative RGS domain

Subcellular localization directed by specific A kinase anchoring proteins (AKAPs) is a mechanism for compartmentalization of cAMP-dependent protein kinase (PKA). Using a two-hybrid screen, a novel AKAP was isolated. Because it interacts with both the type I and type II regulatory subunits, it was defined as a dual specific AKAP or D-AKAP1. Here we report the cloning and characterization of another novel cDNA isolated from that screen. This new member of the D-AKAP family, D-AKAP2, also binds both types of regulatory subunits. A message of 5 kb pairs was detected for D-AKAP2 in all embryonic stages and in all adult tissues tested. In brain, skeletal muscle, kidney, and testis, a 10-kb mRNA was identified. In testis, several small mRNAs were observed. Therefore, D-AKAP2 represents a novel family of proteins. cDNA cloning from a mouse testis library identified the full length D-AKAP2. It is composed of 372 amino acids which includes the R binding fragment, residues 333-372, at its C-terminus. Based on coprecipitation assays, the R binding domain interacts with the N-terminal dimerization domain of RIalpha and RIIalpha. A putative RGS domain was identified near the N-terminal region of D-AKAP2. The presence of this domain raises the intriguing possibility that D-AKAP2 may interact with a Galpha protein thus providing a link between the signaling machinery at the plasma membrane and the downstream kinase.     

Diffusion bonding of ferritic oxide dispersion strengthened alloys to austenitic superalloys

The superior high temperature mechanical strength and oxidation resistance of ferritic oxide dispersion strengthened (ODS) tubular alloys are compromised by the difficulties encountered in joining. Conventional fusion welding techniques generate a weld fusion zone which is devoid of the mechanical strength exhibited by the base material. Therefore, more sophisticated solid state joining techniques, such as diffusion bonding, must be employed when joining ODS materials. This paper describes a series of solid state diffusion bonding experiments carried out between two tubular ferritic ODS alloys and two high temperature austenitic alloys. Careful control of bonding conditions produced pressure retaining joints between one of the tubular ODS alloys and both austenitic alloys. The successful joint design was incorporated into the manufacture of a tubular creep component, which enabled a series of internally pressurized creep tests to be carried out. The microstructure developed at the bond interface of each of the four separate material couples is described and the high temperature performance of the pressure retaining joints is discussed.     

Role of Ponded Turbidity Currents in Reservoir Trap Efficiency

The capacity to store water in a reservoir declines as it traps sediment. A river entering a reservoir forms a prograding delta. Coarse sediment (e.g., sand) deposits in the fluvial topset and avalanching foreset of the delta, and is typically trapped with an efficiency near 100%. The trap efficiency of fine sediment (e.g., mud), on the other hand, may be below 100%, because some of this sediment may pass out of the reservoir without settling out. Here, a model of trap efficiency of mud is developed in terms of the mechanics of a turbidity current that plunges on the foreset. The dam causes a sustained turbidity current to reflect and form a muddy pond bounded upstream by a hydraulic jump. If the interface of this muddy pond rises above any vent or overflow point at the dam, the trap efficiency of mud drops below 100%. A model of the coevolution of topset, foreset, and bottomset in a reservoir that captures the dynamics of the internal muddy pond is presented. Numerical implementation, comparison against an experiment, and application to a field-scale case provide the basis for a physical understanding of the processes that determine reservoir trap efficiency.     

Autoimmune hemolytic anemia and posthepatitis-C liver cirrhosis

Here we are presenting the case of a 70-years-old woman who has hepatic cirrhosis anti-HCV and insulin-dependent diabetes mellitus, without relevant epidemiologic ascendants or previous transfusions and HBV, HIV negatives. On admission to our hospital she showed signs of autoimmune hemolytic anaemia (AHA) which was confirmed by positive direct Coombs test and an improvement in blood test after corticoid treatment. Having discarded other possible causes such as drugs infectious diseases or essential mixed cryoglobulinemia (CME), we put forward the possible association between AHA and infection by HCV, where AHA was an extrahepatic immunological manifestation of HCV. This fact has never been brought to light in previous medical literature.     

Respiratory mechanics of the horse during the first year of life

This study investigated the developmental changes in the mechanical properties of the respiratory system in growing horses. Pulmonary mechanics and lung volumes were serially measured in anesthetized foals during the first year of life. Quasi-static pressure-volume curves were generated, and functional residual capacity (FRC) was measured using a closed nitrogen equilibration technique. At birth, chest wall compliance normalized to body weight was substantially less than that reported in other less precocious newborn species, while lung compliance normalized to body weight was similar to values reported for other species. Characteristics of the transition from the neonatal to adult respiratory system in the foal included a decrease in the ratios of chest wall to lung compliance (Cw/CL) and the unstressed volume of the chest wall to TLC, and a constant FRC/TLC throughout most of the study period. The somatic growth of the foal and its respiratory system were uneven processes, with increases in lung volume lagging increases in overall body size.     

Health trajectories: long-term dynamics among black and white adults

Flow cytometry is a unique technology useful in the examination of effects of immunotoxic agents on target cells of the immune system. The purpose of this workshop was to provide an overview of the use of flow cytometry in new and established models of immunotoxicity, with emphasis on the potential applications, assay validation, and potential pitfalls. This overview begins with a discussion of methods useful in the assessment of Ca2+-dependent mechanisms of lymphoid cell activation in surface marker-defined human B cells, T cells, and monocytes. A discussion of the use of flow cytometry in analysis of apoptosis is also presented in this paper. The second paper presents data on the development and use of flow cytometry as an alternative to a Cr51 release assay for an assessment of cytotoxic T cell activation. The use of surface markers for characterizing and distinguishing the effects of chemical irritants from sensitizers is next presented, followed by an overview of the use of fluorescent probes to assess cell thiol status and overall oxidant-induced injury to lymphoid cells. Finally, an interlaboratory study designed to compare and evaluate the use of flow cytometry procedures in rat splenic cell subtyping is presented. Overall, these studies demonstrate the utility of flow cytometry assays in immunotoxicologic research, but further efforts are needed in the validation of many of these assays for routine use in immunotoxicologic testing.     

Arterial reactivity is enhanced in genetic males taking high dose estrogens

OBJECTIVES: We sought to assess whether high dose estrogen treatment is associated with enhanced arterial reactivity in genetic males. BACKGROUND: Although estrogens have been shown to enhance arterial reactivity in women, and are thereby thought to confer cardiovascular benefit, the vascular effects of long-term estrogen therapy in genetic males is unknown. METHODS: We studied the arterial physiology of 30 genetic males--15 male to female transsexuals receiving long-term high dose estrogen therapy and 15 healthy male control subjects matched for age, smoking history and vessel size. Using external vascular ultrasound, brachial artery diameter was measured at rest, after flow increase (causing endothelium-dependent dilation [EDD]) and after nitroglycerin (GTN), an endothelium-independent dilator. Blood pressure, cholesterol and testosterone levels were also measured in each subject. RESULTS: Total testosterone and free testosterone index levels were lower in the transsexuals compared with the control subjects (p < 0.001). In contrast, EDD was significantly higher in the transsexuals than in the control males (mean [+/-SD] 7.1 +/- 3.1% vs. 3.2 +/- 2.8%, p = 0.001), as was the GTN response (21.2 +/- 6.7% vs. 14.6 +/- 3.3%, p = 0.002). Total and high density lipoprotein cholesterol, blood pressure levels and baseline vessel size were similar in the two groups. On multivariate analysis, enhanced EDD was associated independently with estrogen therapy (p = 0.02) and with low total cholesterol (p = 0.04). An enhanced GTN response was also significantly associated with estrogen therapy (p = 0.03). CONCLUSIONS: Long-term treatment with high dose estrogens is associated with enhanced arterial reactivity in genetic males, which may be due to the effects of estrogen excess or androgen deprivation, or both.     

Central motor conduction evaluation in glycogenosis type III

We report a 20-year-old man affected by glycogenosis type III with distal muscle weakness, more severe in distal leg muscles. The electromyogram showed myopathic features. Nerve conduction studies and central motor conduction after magnetic stimulation of the brain were normal. Our results suggest that there is no involvement of central motor pathways in this disease.     

The placebo effect and clinical research in urology

A case of a large dentigerous cyst containing a canine tooth in the maxillary antrum is presented. This case is of interest due because of its extensiveness and the presence of a canine tooth in the roof of the maxillary sinus. In addition, this caused a right-sided epiphora. Enucleation of the cyst containing the ectopic tooth was made.