Junctional adhesion molecule-A deficiency increases hepatic ischemia-reperfusion injury despite reduction of neutrophil transendothelial migration

The endothelial receptors that control leukocyte transmigration in the postischemic liver are not identified. We investigated the role of junctional adhesion molecule-A (JAM-A), a receptor expressed in endothelial tight junctions, leukocytes, and platelets, for leukocyte transmigration during hepatic ischemia-reperfusion (I/R) in vivo. We show that JAM-A is up-regulated in hepatic venular endothelium during reperfusion. I/R-induced neutrophil transmigration was attenuated in both JAM-A-/- and endothelial JAM-A-/- mice as well as in mice treated with an anti-JAM-A antibody, whereas transmigration of T cells was JAM-A independent. Postischemic leukocyte rolling remained unaffected in JAM-A-/- and endothelial JAM-A-/- mice, whereas intravascular leukocyte adherence was increased. The extent of interactions of JAM-A-/- platelets with the postischemic endothelium was comparable with that of JAM-A+/+ platelets. The I/R-induced increase in the activity of alanine aminotransferase (ALT)/aspartate aminotransferase (AST) and sinusoidal perfusion failure was not reduced in JAM-A-/- mice, while the number of terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling (TUNEL)-positive hepatocytes was significantly higher. Thus, we show for the first time that JAM-A is up-regulated in hepatic venules and serves as an endothelial receptor of neutrophil transmigration, but it does not mediate leukocyte rolling, adhesion, or platelet-endothelial cell interactions. JAM-A deficiency does not reduce I/R-induced microvascular and hepatocellular necrotic injury, but increases hepatocyte apoptosis, despite attenuation of neutrophil infiltration.     

Diffuse cystic lung diseases: correlation between radiologic and functional status

BACKGROUND: High-resolution CT (HRCT) scanning plays an important role in the diagnosis of diffuse cystic lung diseases (DCLDs). However, its role in the clinical evaluation of patients affected by DCLD has not yet been well-clarified. At present, pulmonary function tests are the only methods available for the evaluation of lung impairment due to these diseases, but their sensitivity and reliability are still limited. PURPOSE: The aim of this study was to correlate the quantitative score of cystic-aerial lesions obtained by a HRCT density mask (DM) software with pulmonary function data in DCLDs. METHODS: Spirometry, lung volumes, diffusion capacity, arterial blood gas (ABG) analysis, 6-min walking test (6-MWT), and HRCT with DM quantitative evaluation were performed in a cohort of 25 patients (lymphangioleiomyomatosis [LAM], 13 patients; Langerhans cells histiocytosis [LCH], 12 patients). Linear regression was used for the statistical analysis. The sum and mean of the air-trapping percentages at three different levels of DM study (ie, aortic arch, left lower lobe bronchus origin, and 2 cm from the diaphragmatic muscle), and various functional parameters and exercise performance values were matched for the analysis. RESULTS: An obstructive pattern was present in 13 patients (52%; LCH group, 8 patients; LAM group, 5 patients). A predominant restrictive pattern was detected only in three patients (12%; LCH group, two patients; LAM group, one patient). Nine patients (36%) walked < 350 m, and 14 of 23 patients (61%) had a significant decrease in arterial oxygen saturation during exercise (> 4 U). The results of DM quantitative study (sum and mean) significantly correlated with FVC (r = - 0.56; p < 0.001), FEV(1)/vital capacity (r = - 0.94; p < 0.002), midexpiratory phase of forced expiratory flow (r = - 0.84; p < 0.05), FEV(1) (r = - 0.82; p < 0.05), and diffusing capacity of the lung for carbon monoxide (r = - 0.82; p < 0.05), bronchial airway resistance (r = 0.79; p < 0.05), and distance walked on the 6-MWT (r = - 0.53; p < 0.05). No significant correlation was found with the results of ABG analysis. CONCLUSIONS: In DCLDs, HRCT scans with quantitative assessment performed by a DM software showed a very good correlation with functional parameters. Therefore, DM could be considered, in combination with a complete functional assessment, in the initial evaluation of patients affected by DCLDs. However, further studies are needed to assess its usefulness in the follow-up of these patients.     

Electrophysiological effects mediated by the stimulation of cardiac β2-adrenoceptors with tulobuterol

Summary We studied the electrophysiological effects of the specific ₂-agonist tulobuterol in the guinea-pig sinus node and in sheep cardiac Purkinje fibers. Stimulation of ₂-adrenoceptors by tulobuterol resulted in a slight increase in the rate of firing of the sinus node. In Purkinje fibers, however, automaticity was not affected up to concentrations of 10^–6 M. Consistently, tulobuterol (10^–8–10^–6 M) did not affect the pacemaker current studied under voltage-clamp conditions. In the same range of concentrations (10^–8–10^–6 M) tulobuterol dose-dependently increased the contractile force of driven Purkinje fibers. Tulobuterol, at a very high concentration (10^–5 M), had membrane depressant effects as demonstrated by the block of automaticity induced in the spontaneously beating Purkinje fibers and by the reduction of the maximum rate of depolarization in driven preparations.Our results suggest that stimulation of ₂-adrenoceptors with tulobuterol in sheep Purkinje fibers is associated with an inotropic rather than a chronotropic effect. On the whole, the data confirm the lack of cardiac side effects of tulobuterol.     

The Agmatine-Containing Poly(Amidoamine) Polymer AGMA1 Binds Cell Surface Heparan Sulfates and Prevents Attachment of Mucosal Human Papillomaviruses

The agmatine-containing poly(amidoamine) polymer AGMA1 was recently shown to inhibit the infectivity of several viruses, including human papillomavirus 16 (HPV-16), that exploit cell surface heparan sulfate proteoglycans (HSPGs) as attachment receptors. The aim of this work was to assess the antiviral activity of AGMA1 and its spectrum of activity against a panel of low-risk and high-risk HPVs and to elucidate its mechanism of action. AGMA1 was found to be a potent inhibitor of mucosal HPV types (i.e., types 16, 31, 45, and 6) in pseudovirus-based neutralization assays. The 50% inhibitory concentration was between 0.34 μg/ml and 0.73 μg/ml, and no evidence of cytotoxicity was observed. AGMA1 interacted with immobilized heparin and with cellular heparan sulfates, exerting its antiviral action by preventing virus attachment to the cell surface. The findings from this study indicate that AGMA1 is a leading candidate compound for further development as an active ingredient of a topical microbicide against HPV and other sexually transmitted viral infections.     

Dimensions of psychological dysfunction in patients with fibromyalgia: development of an Italian questionnaire

Our objective was to observe whether dysfunctional psychological dimensions of pain could be detected in fibromyalgia patients through the development of a new questionnaire. An original questionnaire composed of 51 items was given to 250 patients (185 females and 65 males, mean age 55±12.8 years) suffering from chronic fibromyalgia according to the criteria of the Multicenter Criteria Committee of the American College of Rheumatology. A Varimax computerized program of factorial analysis with orthogonal and oblique rotation of the axes was used to analyze the data. Five strong independent factors were identified: 1) catastrophizing and 2) external control beliefs (cognitive); 3) alexithymia (emotional); 4) restless behavior (behavioral); and 5) need for support (relational). Our questionnaire is a preliminary development of an Italian language psychological characterization of FM patients which may be a relevant and useful tool for the evaluation of the outcome of clinical/psychological treatment of FM.Abbreviations FM Fibromyalgia     

RANKL Expression Is Increased in Circulating Mononuclear Cells of Patients with Calcific Aortic Stenosis

We aimed to investigate whether the expression of the OPG/RANK/RANKL triad in peripheral blood mononuclear cells (PBMC) and circulating levels of markers of ectopic mineralization (OPG, FGF-23, PPi) are modified in patients with calcific aortic valve disease (CAVD). We found that patients affected by CAVD (n?=?50) had significantly higher circulating levels of OPG as compared to control individuals (p?=?0.003). No differences between the two groups were found in FGF-23 and PPi levels. RANKL expression was higher in the PBMC from CAVD patients (p?=?0.018) and was directly correlated with the amount of valve calcification (p?=?0.032). In vitro studies showed that treatment of valve interstitial cells (VIC) with RANKL plus phosphate was followed by increase in matrix mineralization (p?=?0.001). In conclusion, RANKL expression is increased in PBMC of patients with CAVD, is directly correlated with the degree of valve calcification, and promotes pro-calcific differentiation of VIC.     

Perianal fistulae following infliximab treatment: clinical and endosonographic outcome

BACKGROUND: Management of perianal and rectovaginal fistulae complicating Crohn's disease (CD) is unsatisfactory. Infliximab is effective in the treatment of fistulating CD. However, reopening of fistulae is frequent, suggesting the persistence of deep fistula tracts despite superficial healing. In this study, the clinical and endosonographic behavior of perianal fistulae were evaluated following infliximab infusions, as well as the role of anal endosonography (AE) in predicting their outcome. METHODS: Thirty CD patients presenting with perianal and/or rectovaginal fistulae received an infusion of infliximab at a dose of 5 mg/kg at weeks 0 (entry into the study), 2, and 6. Laboratory and clinical assessments were repeated at same intervals and at week 10. AE was performed at entry and at week 10. Thereafter, the perianal region was re-examined every 6 months, and patients were investigated regarding draining of the fistula in the previous months. RESULTS: Fifteen patients (53.6%) showed closure of the fistulae at week 10, but only 5 patients had the fistula tracts disappeared at AE. Clinical and AE closure of rectovaginal fistulae was less prevalent than that of perianal fistulae [14.3% versus 63.6% at week 6 (p = 0.035); 28.6% versus 59.1% at week 10 (p = 0.21); 14.3% versus 22.7% at AE (p = 1.00)]. The behavior of fistulae was not affected by their number and AE classification, presence of rectal disease, or setons. Twenty patients with perianal fistulae were followed for a median of 15.5 months. Patients with closed perianal fistulae at week 10 and disappearance of fistulae tract at AE showed a lower relapse rate than those with endosonographic persistence of fistula tract. CONCLUSIONS: Infliximab can heal perianal and rectovaginal fistulae in approximately 60% and 30% of patients, respectively. Despite closure, most fistula tracts are still detectable at AE. Persistence of the internal tract is a condition at higher risk of fistula recurrence.     

Progress towards the development of a HIV-1 gp41-directed vaccine

The HIV-1 gp41 envelope glycoprotein mediates fusion of the viral and cellular membranes. The core of the gp41 ectodomain undergoes a receptor-triggered conformational transition forming a trimeric, alpha-helical coiled-coil structure. This trimer-of-hairpins species facilitates insertion of the viral envelope protein into the host cell membrane promoting viral entry. The prefusogenic conformation of gp41 is capable of stimulating a neutralizing antibody immune response and is therefore an attractive therapeutic target. Several broadly neutralizing HIV-1 monoclonal antibodies which bind to gp41 have been characterized and include 4E10, Z13 and 2F5. A conserved segment of gp41 (residues 661-684) has been identified as the epitope for the HIV-1 neutralizing antibody 2F5 (MAb 2F5). MAb 2F5 has attracted considerable attention because of the highly conserved recognition epitope and the ability to neutralize both laboratory-adapted and primary viral isolates. Antibodies which recognize the immunodominant regions of gp41 may provide protection against HIV infection if elicited at appropriate concentrations. Here we review the rational design, structure-activity relationships and conformational features of both linear and constrained peptide immunogens incorporating variants of both the 2F5 epitope and the gp41 ectodomain. This review describes a rational design approach combining structural characterization with traditional SAR to optimize MAb 2F5 antibody affinities of gp41-based peptide immunogens. The immunogens are shown to stimulate a high titer, peptide-specific immune response; however, the resulting antisera were incapable of viral neutralization. The implication of these findings with regard to structural and immunological considerations is discussed.     

Increased arterial stiffness in normoglycemic normotensive offspring of type 2 diabetic parents

Diabetes is associated with a reduction of arterial distensibility. Limited information exists regarding whether or how early this appears in the course of the disease. We studied 54 normoglycemic, normotensive, healthy offspring of 2 parents with type 2 diabetes mellitus and 55 age- and sex-matched healthy control subjects. Carotid diastolic diameter and systodiastolic change were measured by echo tracking (Wall Track System) and wall thickness by echocolor Doppler (Sonos 5500, Philips). Pulse pressure was measured by a semiautomatic device positioned on the brachial artery and arterial distensibility calculated by Reneman formula. Blood pressure, blood glucose, glycohemoglobin, and insulin sensitivity (homeostasis model assessment index) were normal or only slightly elevated and by and large similar in the 2 groups. Compared with control subjects, offspring of diabetic parents showed similar carotid diameters at diastole and a reduced increase in carotid diameter at systole (-16%), a reduced carotid artery distensibility (-30%), and an increased pulse pressure (+21.8%), all differences being statistically significant (P<0.05) and persisting in subgroups with elevated or normal body mass index values (<25 and >or=25 kg/m(2)). Carotid artery wall thickness was not different between the 2 groups. Thus, subjects with predisposition to diabetes show carotid artery stiffening even in the absence of blood pressure alterations, as well as substantial alterations of glucose metabolism, body mass index, and changes in carotid wall thickness. This suggests that, in diabetes, alterations in arterial mechanical properties represent an early phenomenon, which may occur in the absence of metabolic and blood pressure alterations.