A Very Long-term Longitudinal Study on the Evolution and Clinical Outcomes of Persistent Iatrogenic Atrial Septal Defect After Cryoballoon Ablation

Background

Persistent iatrogenic atrial septal defect (iASD) is a common but poorly characterized complication after cryoballoon (CB) pulmonary vein isolation (PVI) procedures. We therefore investigate its prevalence, evolution, risk factors, and clinical outcomes in a prospective longitudinal study.

Results From a Large,Multicenter, Retrospective Analysis On Radium223 Use in Metastatic Castration-resistant Prostate Cancer (mCRPC) in the Triveneto Italian Region

Background

Radium 223 was introduced for metastatic castration-resistant prostate cancer based on the results of a randomized controlled trial showing risk reduction for death and skeletal events. Our aim was to evaluate the outcome of patients receiving radium 223 in a real-world setting.

Relaxin down-regulates renal fibroblast function and promotes matrix remodelling in vitro.

BACKGROUND: Renal fibroblasts are important effector cells in tubulointerstitial fibrosis, with experimental antifibrotic strategies focusing on the functional down-regulation of these cells. Several experimental models of fibrosis have provided evidence for the effectiveness of the polypeptide hormone relaxin as a potential antifibrotic agent. This study was conducted to further elucidate the antifibrotic mechanisms of relaxin on renal fibroblasts in vitro. METHODS: Rat cortical fibroblasts were obtained from outgrowth culture of renal tissue isolated from kidneys 3 days post-unilateral ureteric obstruction and constituted 100% of cells studied. A relaxin radio-receptor assay was used to establish binding of relaxin to renal fibroblasts in vitro. Functional studies then examined the effects of H2 relaxin (0, 1, 10 and 100 ng/ml) on fibroblast kinetics, expression of alpha-smooth muscle actin (alpha-SMA), total collagen synthesis, collagenase production and collagen-I lattice contraction. CTGF mRNA expression was also measured by northern analysis. RESULTS: H2 relaxin bound with high affinity to rat renal fibroblasts, but receptor numbers were low. Consistent with its previously reported bimodal effect, transforming growth factor (TGF-beta 1) reduced fibroblast proliferation, an effect abrogated by H2 relaxin. Fibroblasts exposed to H2 relaxin (100 ng/ml) for 24 h demonstrated decreased immunostaining for alpha-SMA and reduced alpha-SMA protein expression compared with controls. There was a trend for a relaxin-mediated reduction in total collagen synthesis and alpha 1(I) mRNA expression with large dose-related increases in collagenase protein expression being observed. TGF-beta 1-stimulated collagen-I lattice contraction was significantly inhibited following co-incubation with 100 ng/ml relaxin. Incremental doses of H2 relaxin had no significant effect on CTGF mRNA expression. CONCLUSIONS: The findings of this study suggest that the antifibrotic effects of relaxin involve down-regulation of fibroblast activity, increase in collagenase synthesis and restructuring of collagen-I lattices, which are consistent with its known physiological role of matrix remodelling. Although there appears to be an interaction between TGF-beta 1 and H2 relaxin, this does not appear to involve a reduction in CTGF mRNA expression.     

Ultrastructure and membrane permeability of cultured pancreaticβ-cells exposed to alloxan or 6-hydroxydopamine

Summary Stereological techniques on electron microscopy micrographs were used to evaluate the morphological changes of cultured islet cells that had been exposed to alloxan or 6-hydroxydopamine.Trypan Blue exclusion by cells cultured for 3 days indicated that the cells were 100% viable. Electron microscopy revealed that nearly all of the surviving cultured cells were cells.Exposure to 5 mmol/l alloxan or 1–5 mmol/l 6-hydroxydopamine for 10 or 30 min caused a general swelling of the cultured cells with a concomitant swelling of mitochondria and nuclei. The size of the secretory granules was not affected by the drugs. Only 3–10% of the cells excluded Trypan Blue after exposure to 5 mmol/l alloxan or 6-hydroxydopamine.The data conform with the hypothesis that a primary action of alloxan and 6-hydroxydopamine is at the plasma membrane level of cells.Abbreviations and definitions A _cell Cell profile area (µm²), surface area of one cell section surface - V _n Nuclear volume density (%), number of points over the nucleus divided by the number of points over the total cell area × 100 - V _m Mitochondrial volume density (%), number of points over mitochondria divided by hits over the cytoplasm (points over the cell minus points over the nucleus) × 100 - V _g Granular volume density (%), number of points over granules divided by hits over the cytoplasm × 100     

Study of β‐casein denaturation by microparticle‐enhanced nephelometric immunoassay

Rabbit anti‐native bovine ß‐casein antiserum reacted with native ß‐casein and fragments f( 1–105/7) and f( 106–209) formed during ß‐casein proteolysis by plasmin. Agglutination of ß‐casein‐coated microparticles by anti‐native ß‐casein antiserum was weakly inhibited by ß‐casein f(1–105/7) and ß‐casein f( 106–209) (0·04 and 1·4%, respectively, compared with native ß‐casein). Immunoreactivity of these ß‐casein peptides in microparticle‐enhanced nephelometric immunoassay was more preserved in the whole ß‐casein than in its isolated fragments. The protein concentration producing 50% inhibition of the ß‐casein‐coated microparticle agglutination with anti‐native ß‐casein antiserum increased during ß‐casein denaturation. A microparticle‐enhanced nephelometric immunoassay, quantifying changes of this inhibiting protein concentration, permitted detection of alteration of the immunoreactivity of ß‐casein during its plasmin proteolysis and heat denaturation, providing an adequate test for the integrity of the whole molecule.     

HLA-DR and H-2E transgenes differentially mediate TCR-specific positive selection

The use of HLA transgenic mice in models of immunity and diseaseassumes that human MHC molecules are able to contribute towardthe positive selection of the mouse TCR repertoire. As an initialstep towards analysis of this we have compared the relativeability of DR/Eß or E/Eß complexes to induceT cell receptor (TCR) positive selection in H-2Ea and HLA-DRAtransgenic mice lacking endogenous E. The results show that,like E/Eß, the hybrid DR/ß complexes arecapable of mediating positive selection of V_ß2⁺;,V_ß6⁺, and V_ß10⁺ cells. However, differenceswere found between the effects of the two transgenes. Thus,while V_ß6⁺ cells were efficiently selected in bothH-2Ea and DRA transgenic mice, positive selection of V_ß10⁺cells was less apparent in the DRA transgenic mice. Variationbetween Ea and DRA transgenic mice is consistent with the notionthat this process is dependent on differential binding of endogenouspeptides to the E/Eß and DR/Eß complexes.Furthermore, contrary to expectations, in neither set of micewas positive selection limited solely to the CD4⁺ subset. Thus,examples were found in which V_ß-specific positiveselection was confined to either the CD4⁺ or CD8⁺ subsets, andothers in which both subpopulations were concomltantly increased.In the case of V_ß2 positive selection, H-2Ea transgenicmice showed expansion of these cells in both the CD4⁺ and CD8⁺subpopulations whlle in DRA transgenic mice this occurred predominantlyin the CD8⁺ subpopulatlon.     

IL-1 is required for allergen-specific Th2 cell activation and the development of airway hypersensitivity response

IL-1 is a pro-inflammatory cytokine consisted of two molecular species, IL-1alpha and IL-1beta, and the IL-1 receptor antagonist (IL-1Ra) is a natural inhibitor of both molecules. Although it is suggested that IL-1 potentiates immune responses mediated by T(h)2 cells, the role of IL-1 in asthma still remains unclear. In this study, we demonstrate that the ovalbumin (OVA)-induced airway hypersensitivity response (AHR) in IL-1alpha/beta-deficient (IL-1alpha/beta(-/-)) mice was significantly reduced from the levels seen in wild-type mice, whereas the responses seen in IL-1Ra(-/-) mice were profoundly exacerbated, suggesting that IL-1 is required for T(h)2 cell activation during AHR. OVA-specific T cell proliferation, IL-4 and IL-5 production by T cells, and IgG1 and IgE production by B cells in IL-1alpha/beta(-/-) mice were markedly reduced compared with these responses in wild-type mice; such responses were enhanced in IL-1Ra(-/-) mice. Using IL-1alpha(-/-) and IL-1beta(-/-) mice, we determined that both IL-1alpha and IL-1beta are involved in this reaction. Both IgG1 and IgE levels were reduced in IL-1beta(-/-) mice, while only IgE levels were affected in IL-1alpha(-/-) mice, indicating a functional difference between IL-1alpha and IL-1beta. These observations indicate that IL-1 plays important roles in the development of AHR.     

Prevention of endotoxin shock by an antibody against leukocyte integrin {beta}2 through inhibiting production and action of TNF

Septic shock remains a serious disorder associated with highmortality. Accumulating evidence indicates that TNF is a majorand essential mediator of endotoxin shock. We report here thatadministration of an antibody against CD18 dramatically reducedendotoxin-induced shock inrabbits as revealed by preventionof severe hypotension, metabolic acidosis and a pathologicalchange suggestive of disseminated intravascular coagulationwith concomitant inhibition of elevation of plasma TNF activity.The anti-CD18 antibody also inhibited the hypotension inducedby administering recombinant TNF. Furthermore, an antibody againsta ligand for CD18 complexes, intercellular adhesion molecule-1,also prevented TNF-induced shock as well as endotoxin shockinrabbits. These observations suggest that adhesion of leukocytesto endothelium may be of primary importance in the action ofTNF as well as in the production of TNF in vivo and that theantibody against adhesion molecules could be of therapeuticbenefit in life-threatening septic shock in humans.     

Induction of Ly-6A/E expression by murine lymphocytes after in vivo immunization is strictly dependent upon the action of IFN-alpha/beta and/or IFN-gamma

Ly-6A/E is a phosphatidylinositol-linked membrane protein which mediates murine T and B cell signalling. IFN-gamma, IFB-alpha/beta, LPS, and IL-4 have all been reported to induce or upregulate Ly-6A/E by normal lymphocytes. Since no systematic study has addressed the stimulant selectivity of Ly-6A/E expression by murine lymphocytes nor investigated its induction and regulation during primary in vivo immune responses we analyzed in vitro Ly-6A/E expression after murine stimuli and during a number of distinct in vivo immunizations. We show that LPS induces B cell Ly-6A/E in vitro by stimulating the release of IFN-alpha/beta by 'contaminating' adherent cells. In the presence of anti-IFN-gamma + anti-IFN-alpha/beta antibodies, no Ly-6A/E was induced upon addition of multiple cytokines, including IL-4, or mitogenic doses of anti-Ig antibody. Furthermore, IFN-gamma-containing, CD4+ T cell (Th1) supernatants potently induced Ly-6A/E by murine B cells whereas IL-4-containing (Th2) supernatants were either weak or ineffective; anti-IFN-gamma + anti-IFN-alpha/beta inhibited Ly-6A/E induction by both Th1 and Th2 supernatants. Immunization of mice with Brucella abortus or poly (I).poly (C) resulted in induction of Ly-6A/E expression by virtually all B and T cells, whereas injection of G alpha M delta led to peak induction of Ly-6A/E by approximately 50% of both B and T cells. Lymphocytes from mice infected with the nematode parasites Nippostrongylus brasiliensis or Heligmosomoides polygyrus expressed no Ly-6A/E.(ABSTRACT TRUNCATED AT 250 WORDS)