A role of Hsp60 in autoimmune diabetes: analysis in a transgenic model

A pathogenic role for self-reactive cells against the stress protein Hsp60 has been proposed as one of the events leading to autoimmune destruction of pancreatic beta cells in the diabetes of nonobese diabetic (NOD) mice. To examine this hypothesis, we generated transgenic NOD mice carrying a murine Hsp60 transgene driven by the H-2E alpha class II promoter. This would be expected to direct expression of the transgene to antigen-presenting cells including those in the thymus and so induce immunological tolerance by deletion. Detailed analysis of Hsp60 expression revealed that the endogenous gene is itself expressed strongly in thymic medullary epithelium (and weakly in cortex) yet fails to induce tolerance. Transgenic mice with retargeted Hsp60 showed overexpression of the gene in thymic cortical epithelium and in bone marrow-derived cells. Analysis of spontaneous T-cell responses to a panel of self and heterologous Hsp60 antigens showed that tolerance to the protein had not been induced, although responses to an immunodominant 437-460 epitope implicated in disease were suppressed, probably indicating an epitope shift. This correlated with changes in disease susceptibility: insulitis in transgenic mice was substantially reduced so that pathology rarely progressed beyond periislet infiltration. This was reflected in a substantial reduction in hyperglycemia and disease. These data indicate that T cells specific for some epitopes of murine Hsp60 are likely to be involved in the islet-cell destruction that occurs in NOD mice.     

Antimutagenic activity of extracts from Japanese eggplant

There is increasing evidence that Schwann cells play an important role in the pathogenesis of autoimmune inflammatory peripheral nerve disease. Schwann cells have been reported to express major histocompatibility complex class I and II (MHC I and II) and intercellular adhesion molecule-1 (ICAM-1), and to produce interleukin-1 (IL-1), prostaglandin E2 and thromboxane A2. In this study we investigated freshly dissociated neonatal Lewis rat Schwann cells and a SV40 transfected neonatal rat Schwann cell line (Schwann cell line) for production of mRNA for the immunomodulatory cytokines IL-2, IL-4, IL-6, IL-10, interferon-gamma (IFN gamma), and tumor necrosis factor-alpha (TNF alpha) employing RT-PCR. Primary Schwann cells and Schwann cell line were examined following IFN gamma stimulation and were found to express TNF alpha and IL-6 mRNA. These results further support a role for Schwann cell participation in inflammatory responses within the peripheral nervous system (PNS).     

Wool and grain dusts stimulate TNF secretion by alveolar macrophages in vitro

OBJECTIVE: The aim of the study was to investigate the ability of two organic dusts, wool and grain, and their soluble leachates to stimulate secretion of tumour necrosis factor (TNF) by rat alveolar macrophages with special reference to the role of lipopolysaccharide (LPS). METHODS: Rat alveolar macrophages were isolated by bronchoalveolar lavage (BAL) and treated in vitro with whole dust, dust leachates, and a standard LPS preparation. TNF production was measured in supernatants with the L929 cell line bioassay. RESULTS: Both wool and grain dust samples were capable of stimulating TNF release from rat alveolar macrophages in a dose-dependent manner. The standard LPS preparation caused a dose-dependent secretion of TNF. Leachates prepared from the dusts contained LPS and also caused TNF release but leachable LPS could not account for the TNF release and it was clear that non-LPS leachable activity was present in the grain dust and that wool dust particles themselves were capable of causing release of TNF. The role of LPS in wool dust leachates was further investigated by treating peritoneal macrophages from two strains of mice, LPS responders (C3H) and LPS non-responders (C3H/HEJ), with LPS. The non-responder mouse macrophages produced very low concentrations of TNF in response to the wool dust leachates compared with the responders. CONCLUSIONS: LPS and other unidentified leachable substances present on the surface of grain dust, and to a lesser extent on wool dust, are a trigger for TNF release by lung macrophages. Wool dust particles themselves stimulate TNF. TNF release from macrophages could contribute to enhancement of inflammatory responses and symptoms of bronchitis and breathlessness in workers exposed to organic dusts such as wool and grain.     

Origins of comorbidity between conduct and affective disorders

OBJECTIVE: This analysis used methods of structural equation modeling to assess the extent to which comorbidity between conduct and affective disorders could be explained by (1) common or correlated causal factors that influenced both outcomes or (2) reciprocal causation between these conditions. METHOD: Data were obtained during the course of a 16-year longitudinal study of a birth cohort of New Zealand children. The data analyzed comprised measures of conduct and affective disorders at ages 15 and 16 years and data on a series of antecedent childhood factors. RESULTS: Structural equation modeling suggested that a substantial component of the comorbidity between conduct and affective disorders arose because the risk factors associated with the development of conduct disorders in teenagers overlapped and were correlated with the risk factors for adolescent affective disorders; of the shared variance between conduct disorder and affective disorders, more than two thirds was explained by common risk factors. These conclusions were replicated using diagnostically scored measures and methods of categorical data analysis. Model extensions suggested an absence of direct causal pathways between conduct and affective disorders. CONCLUSIONS: A substantial amount of the correlation and comorbidity between conduct and affective disorders arises because the risk factors and life pathways that predispose adolescents to one outcome are also associated with the risk factors and life pathways that predispose adolescents to the other outcome. Nonetheless, even after control for common causal factors, there was evidence of some unexplained comorbidity between conduct and affective disorders.     

Yeast alpha mating factor structure-activity relationship derived from genetically selected peptide agonists and antagonists of Ste2p

alpha-Factor, a 13-amino-acid pheromone secreted by haploid alpha cells of Saccharomyces cerevisiae, binds to Ste2p, a seven-transmembrane, G-protein-coupled receptor present on haploid alpha cells, to activate a signal transduction pathway required for conjugation and mating. To determine the structural requirements for alpha-factor activity, we developed a genetic screen to identify from random and semirandom libraries novel peptides that function as agonists or antagonists of Ste2p. The selection scheme was based on autocrine strains constructed to secrete random peptides and respond by growth to those that were either agonists or antagonists of Ste2p. Analysis of a number of peptides obtained by this selection procedure indicates that Trp1, Trp3, Pro8, and Gly9 are important for agonist activity specifically. His2, Leu4, Leu6, Pro10, a hydrophobic residue 12, and an aromatic residue 13 are important for both agonist and antagonist activity. Our results also show that activation of Ste2p can be achieved with novel, unanticipated combinations of amino acids. Finally, the results suggest the utility of this selection scheme for identifying novel ligands for mammalian G-protein-coupled receptors heterologously expressed in S. cerevisiae.     

Dithioester functionalization of poly(cyclohexene oxide) and its application to obtain block copolymers

A new method of introducing dithioester groups into the polymer chain of poly(cyclohexene oxide) is reported. It includes the use of diaryliodonium salt and an aromatic dithioacid as a redox couple to initiate the cationic polymerization of cyclohexene oxide. It was found that the dithioacid by itself cannot start the polymerization of cationic polymerizable monomers; however, in combination with a diaryliodonium salt, an exothermic reaction was produced, yielding a thiocarbonylthio‐functionalized polyether. Thermal profiles of the redox polymerizations were determined by means of optical pyrometry. A preliminary study showed that when the poly(cyclohexene oxide) functionalized with dithioester groups was introduced into the radical polymerization of styrene, the polystyryl growing radicals reacted with the dithioester‐functionalized polyether to form a block polymer. The amount of polyether actually incorporated into the block copolymer was calculated to be 70% of the initial amount of poly(cyclohexene oxide)/dithiobenzoic acid charged into the reactor. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

A comparison of traditional folk healing concepts with contemporary healing concepts

Health professional interest in folk healing concepts as a means of complementing contemporary health care has flourished within recent years. Yet, despite this seemingly new area of study, many basic tenets of folk healing are consistent with principles ascribed to by modern health professionals. In this article, I elucidate several concepts shared by traditional folk healing systems and the contemporary health care system. These concepts include origin of illness, harmony and balance, motion, colors, symbols, and family and community involvement. The analysis of these concepts should enable nurses to have an advanced understanding of transcultural healing practices, as well as a heightened perspective on the shared dimensions of folk and contemporary health care systems.     

Cross regulation by IL-10 and IL-2/IL-12 of the helper T cells and the cytolytic activity of lymphocytes from malignant effusions of lung cancer patients

STUDY OBJECTIVE: Our previous report demonstrated that there was impairment of local cellular immunity with elevated interleukin-10 (IL-10) and undetectable IL-12 in neoplastic pleural effusion. These findings suggest that the local immune reactions favor the T-helper type 2 (Th2) pathway instead of Th1 pathway. The present study was designed to examine whether local cellular immunity could be manipulated by IL-2 and/or IL-12 treatment, and to determine their effect on the helper T-cell pathways and the cytolytic activity of the effusion-associated lymphocytes (EALs). DESIGN: Using malignant pleural effusions obtained from four patients suffering from adenocarcinoma of lung, we separated the tumor cells from the EALs with Ficol-Hypaque centrifugation, followed by Percoll density centrifugation. To test whether the cytolytic function of lymphocytes could be enhanced by culturing with IL-2 and/or IL-12, lymphocytes were incubated with recombinant IL-2 with/without IL-12 for 6 days. Following this, the tumoricidal activity was assessed in an overnight 5'chromium-release assay. Autologous tumor cells for measuring specific antitumor activity, Daudi cells susceptible to lymphokine-activated killer cells, and NK-susceptible K562 cells were used as target cells. MEASUREMENTS AND RESULTS: After treatment in vitro with IL-2, IL-12, or IL-2 plus IL-12, the Th pathway shifted from Th2 to Th1 type (increased gamma-interferon production). To further study the effect of cytokine treatment on the cytolytic activity of EALs, it was found that after 6-day culturing, the EALs failed to kill any of the three tumor targets, whereas the 6-day cultured peripheral blood lymphocytes (PBLs) gave low level of cytotoxicity against all three tumor targets. Stimulation with IL-2 alone partially restored the immunocompetence of EALs to kill the tumor targets. Stimulation with IL-12 alone showed no significant effect on their cytolytic activity. However, IL-12 synergized with IL-2 to increase the cytolytic activity of EALs and PBLs against autologous tumor targets. This synergistic effect was not found for Daudi cells and K562 cells. CONCLUSIONS: These results suggest that EALs activated with IL-12 in the presence of a low concentration of IL-2, which converted the EALs from Th2 pathway to Th1 pathway, could be an alternative source of antitumor effectors for adoptive immunotherapy of cancer.     

1997 Volvo Award winner in clinical studies. Degenerative lumbar spondylolisthesis with spinal stenosis: a prospective, randomized study comparing decompressive laminectomy and arthrodesis with and without spinal instrumentation

STUDY DESIGN: This prospective study analyzed the influence of transpedicular instrumented on the operative treatment of patients with degenerative spondylolisthesis and spinal stenosis. OBJECTIVES: To determine whether the addition of transpedicular instrumented improves the clinical outcome and fusion rate of patients undergoing posterolateral fusion after decompression for spinal stenosis with concomitant degenerative spondylolisthesis. SUMMARY OF BACKGROUND DATA: Decompression is often necessary in the treatment of symptomatic patients who have degenerative spondylolisthesis and spinal stenosis. Results of recent studies demonstrated that outcomes are significantly improved if posterolateral arthrodesis is performed at the listhesed level. A meta-analysis of the literature concluded that adjunctive spinal instrumentation for this procedure can enhance the fusion rate, although the effect on clinical outcome remains uncertain. METHODS: Seventy-six patients who had symptomatic spinal stenosis associated with degenerative lumbar spondylolisthesis were prospectively studied. All patients underwent posterior decompression with concomitant posterolateral intertransverse process arthrodesis. The patients were randomized to a segmental transpedicular instrumented or noninstrumented group. RESULTS: Sixty-seven patients were available for a 2-year follow-up. Clinical outcome was excellent or good in 76% of the patients in whom instrumentation was placed and in 85% of those in whom no instrumentation was placed (P = 0.45). Successful arthrodesis occurred in 82% of the instrumented cases versus 45% of the noninstrumented cases (P = 0.0015). Overall, successful fusion did not influence patient outcome (P = 0.435). CONCLUSIONS: In patients undergoing single-level posterolateral fusion for degenerative spondylolisthesis with spinal stenosis, the use of pedicle screws may lead to a higher fusion rate, but clinical outcome shows no improvement in pain in the back and lower limbs.     

Follicle-stimulating hormone induces terminal differentiation in a predifferentiated rat granulosa cell line (ROG)

The divergent commitment of ovarian granulosa cells to either proliferation and differentiation or programmed cell death directly reflects the process of follicular dominance and atresia. This process is regulated by FSH and local paracrine factors. To further analyze the role of FSH and intraovarian factors in follicular selection, we have established a rat ovarian granulosa (ROG) cell line from prepubertal (p14) rats. ROG cells are cultured in serum-free medium with activin A, but without FSH. ROG cells bind FSH and respond to FSH by a burst of cell proliferation and increased progesterone secretion. These results support the hypothesis that activin, but not FSH, is an important factor in the maintenance of immature granulosa cells. After exposure of ROG cells to FSH, withdrawal of FSH from the cultures results in apoptotic cell death. ROG cells start active membrane blebbing by 2 h after FSH withdrawal, and most cells die within 7 h. Thus, FSH-induced ROG cells differentiate into a more mature granulosa phenotype, which is nonmitotic and dependent on FSH for survival. The ROG cell line may thus provide a good in vitro model of follicular selection.