Epstein-Barr virus nuclear antigens 1 and 2 in Burkitt lymphoma cell lines containing either 'A'- or 'B'-type virus

Epstein-Barr virus (EBV) has previously been classified into two different types according to the organization of the EB nuclear antigen 2 (EBNA2) gene region. Type A virus hybridizes with probes from B95-8 or M-ABA viruses and the B type virus with probes from the Jijoye virus strain. The substituted region in EBV type B codes for a different, but related EBNA2 antigen, named EBNA2B as opposed to EBNA2A. In this study Burkitt lymphoma cell lines, previously typed according to the EBV viral genomes they carry, as well as some matching lymphoblastoid cell lines were examined by immunoblotting for the expression of both EBNA1 and EBNA2 antigens. Variation in the molecular weight of EBNA1 indicated that both A and B virus types contained a variety of different virus isolates. EBNA2A was identified in all lines carrying A type viral genomes, but was not observed in any of the lines harboring B type virus. EBNA2B was identified in 4 of 10 Burkitt lymphoma lines carrying EBV type B.     

Angiotensin induces the urinary peristaltic machinery during the perinatal period.

The embryonic development of mammalian kidneys is completed during the perinatal period with a dramatic increase in urine production, as the burden of eliminating nitrogenous metabolic waste shifts from the placenta to the kidney. This urine is normally removed by peristaltic contraction of the renal pelvis, a smooth muscle structure unique to placental mammals. Mutant mice completely lacking angiotensin type 1 receptor genes do not develop a renal pelvis, resulting in the buildup of urine and progressive kidney damage. In mutants the ureteral smooth muscle layer is hypoplastic and lacks peristaltic movements. We show that angiotensin can induce the ureteral smooth muscles in organ cultures of wild-type, but not mutant, ureteral tissues and that, in wild-type mice, expression of both renal angiotensin and the receptor are transiently upregulated at the renal outlet at birth. These results reveal a new role for angiotensin in the unique cellular adaptations of the mammalian kidney to the physiological stresses of postnatal life.     

IMMUNOFLUORESCENT STUDIES OF ADENOVIRUS 12 TUMORS AND OF CELLS TRANSFORMED OR INFECTED BY ADENOVIRUSES

Complement-fixing (CF) antibody-positive sera from hamsters bearing adenovirus type 12 (Ad. 12)-induced tumors revealed specific immunofluorescent stainable antigens in essentially all Ad. 12 hamster tumor cells. The antigens were primarily in the form of cytoplasmic flecks; less frequent staining was seen as nuclear flecks or homogeneous staining of nucleus and cytoplasm of a small proportion of cells. Tumor cells did not stain with rabbit antisera to crude Ad. 12 virus or A and C antigens. The hamster serum also stained cytoplasmic flecks in an Ad. 12-induced BALB/c mouse tumor and Ad. 12-"transformed" hamster embryo tissue culture cells. The hamster serum also stained fleck-shaped antigens in hamster and human cell cultures inoculated with homologous and heterologous adenovirus types, although the hamster cells did not react with the rabbit Ad. 12 antiserum. Attempts to identify the fluorescent-stainable fleck-shaped antigens indicated that they are not previously recognized viral antigens and that the cytoplasmic antigens formed in hamster cell cultures inoculated with Ad. 12 are different from those in tumors and in acutely infected human cell cultures.     

Quality assurance for nursing and midwifery education: an analysis of the approach in England

The main purpose of this paper is to discuss conceptual and policy developments for external quality assurance for nurse and midwifery education in England. The current framework was implemented in the academic year 1998/99, and is the subject of a three year evaluation commissioned by the English National Board for Nursing, Midwifery & Health Visiting (ENB). The methods which are being used to evaluate the quality assurance arrangements will be discussed within the context of nursing and midwifery education and practice. The ultimate aim of professionally accredited nursing and midwifery education is to ensure the development of practitioners who are fit for purpose, practice and award. It follows that the quality assurance processes should have the capacity to demonstrate the extent to which professional education meets this aim. This paper will discuss this issue, with particular emphasis on the collaborative review process which is being undertaken by the Quality Assurance Agency and the statutory body for nursing, midwifery and health visiting education. The paper concludes with a discussion of the changes proposed by the government for nursing and midwifery education, and considers the potential impact for quality assurance of health care education.     

Epithelial neutrophil activating peptide-78: a novel chemotactic cytokine for neutrophils in arthritis.

We and others have shown that cells obtained from inflamed joints of rheumatoid arthritis (RA) patients produce interleukin-8, a potent chemotactic cytokine for neutrophils (PMNs). However, IL-8 accounted for only 40% of the chemotactic activity for PMNs found in these synovial fluids. Currently, we have examined the production of the novel PMN chemotactic cytokine, epithelial neutrophil activating peptide-78 (ENA-78), using peripheral blood, synovial fluid, and synovial tissue from 70 arthritic patients. RA ENA-78 levels were greater in RA synovial fluid (239 +/- 63 ng/ml) compared with synovial fluid from other forms of arthritis (130 +/- 118 ng/ml) or osteoarthritis (2.6 +/- 1.8 ng/ml) (P < 0.05). RA peripheral blood ENA-78 levels (70 +/- 26 ng/ml) were greater than normal peripheral blood levels (0.12 +/- 0.04 ng/ml) (P < 0.05). Anti-ENA-78 antibodies neutralized 42 +/- 9% (mean +/- SE) of the chemotactic activity for PMNs found in RA synovial fluids. Isolated RA synovial tissue fibroblasts in vitro constitutively produced significant levels of ENA-78, and this production was further augmented when stimulated with tumor necrosis factor-alpha (TNF-alpha). In addition RA and osteoarthritis synovial tissue fibroblasts as well as RA synovial tissue macrophages were found to constitutively produce ENA-78. RA synovial fluid mononuclear cells spontaneously produced ENA-78, which was augmented in the presence of lipopolysaccharide. Immunohistochemical localization of ENA-78 from the synovial tissue of patients with arthritis or normal subjects showed that the predominant cellular source of this chemokine was synovial lining cells, followed by macrophages, endothelial cells, and fibroblasts. Synovial tissue macrophages and fibroblasts were more ENA-78 immunopositive in RA than in normal synovial tissue (P < 0.05). These results, which are the first demonstration of ENA-78 in a human disease state, suggest that ENA-78 may play an important role in the recruitment of PMNs in the milieu of the inflamed joint of RA patients.     

Detection of immune complexes in acute rheumatic fever and their relationship to HLA-B5.

Employing five radioimmunoassays for immune complexes, the sera of 45 acute and 27 postacute follow-up sera from patients with acute rheumatic fever were examined. All patients experienced actue polyarthritis. Complexes were detected in 89% of acute-phase sera by one assay, 51% by two, 29% by three, and 7% by four. Immune complex values decreased significantly at followup, although some abnormalities persisted. There was no correlation between extra-articular manifestations and the occurrence of circulating immune complexes. Those positive for HLA-B5 demonstrated a significantly more pronounced immune response as measured by circulating immune complexes. The data indicate that circulating immune complexes occur frequently in adults with acute rheumatic fever. The relative frequency of immune complexes detected by multiple techniques in B5-positive, compared with B5-negative, patients suggests a genetic basis for the development of immune complexes in these patiemts.     

Resilience in Environmental Risk and Impact Assessment: Concepts and Measurement

Different resilience concepts have different assumptions about system dynamics, which has implications for resilience-based environmental risk and impact assessment. Engineering resilience (recovery) dominates in the risk assessment literature but this definition does not account for the possibility of ecosystems to exist in multiple regimes. In this paper we discuss resilience concepts and quantification methods. Specifically, we discuss when a system fails to show engineering resilience after disturbances, indicating a shift to a potentially undesired regime. We show quantification methods that can assess the stability of this new regime to inform managers about possibilities to transform the system to a more desired regime. We point out the usefulness of an adaptive inference, modelling and management approach that is based on reiterative testing of hypothesis. This process facilitates learning about, and reduces uncertainty arising from risk and impact.     

Evaluation of low back muscle surface EMG signals using wavelets

OBJECTIVE: To compare the ability of observers to correctly detect the reaction time of erector spinae response to unexpected load by inspecting nonprocessed electromyographic signals versus inspection of wavelet transformed electromyographic signals and versus automatic detection on the same wavelet transformed signals. BACKGROUND: Traditionally, electromyographic signal analysis is performed using Fourier transform based methods. However, muscle response to transients such as unexpected load, have limitations when using these methods of electromyographic processing. DESIGN: A comparison was made of the three methods using the same signals attained during sudden loading of the trunk. METHODS: 11 chronic low back pain patients and eleven normal subjects were investigated in sudden loading. Surface electromyographic signals were obtained from the erector spine muscle at L3. The ability of observers to detect reaction time of erector spinae muscle responses of nonprocessed electromyographic signals versus inspection of wavelet transformed electromyographic signals versus an automatic peak detection program was determined. RESULTS: The results have shown that the spine muscle reaction time was easier and more accurately determined in the wavelet domain rather than in its original signal representation. CONCLUSION: Wavelet transform methods improved the analysis of electromyographic signals in the time domain by facilitating the determination of the time of muscle activity. RELEVANCE: Wavelet transform could be a valuable tool for electromyographic analysis in resolving the psychophysical problem of perception involved in the analysis of nonprocessed signals. In clinical environments, where the speed and the accuracy of the analysis of electromyographic signal is critical, the wavelet based signal processing could be very important.