Increased elastic microfibrils and thickening of fibroblastic nuclear lamina in canine cutaneous asthenia

Cutaneous asthenia is a hereditary connective tissue disease, primarily of dogs and cats, resembling Ehlers-Danlos syndrome in man. Collagen dysplasia results in skin hyperextensibility, skin and vessel fragility, and poor wound healing. The purpose of this study was to describe the histological findings in a dog with a collagenopathy consistent with cutaneous asthenia. An 8-month-old crossbreed female dog presented with lacerations and numerous atrophic and irregular scars. The skin was hyperextensible and easily torn by the slightest trauma. Ultrastructurally, the dermis was comprised of elaunin and oxytalan microfibrils. These are immature fibres in which the fibrillar component is increased but elastin is reduced. Collagen fibres were profoundly disorganized. The fibrils had a highly irregular outline and a corroded appearance when viewed in cross-section, and were spiralled and fragmented in a longitudinal view. Dermal fibroblasts displayed a conspicuous thickening of the nuclear lamina. Nuclear lamins form a fibrous nucleoskeletal network of intermediate-sized filaments underlying the inner nuclear membrane. Mutations in lamins or lamin-associated proteins cause a myriad of genetic diseases collectively called laminopathies. Disruption of the nuclear lamina seems to affect chromatin organization and transcriptional regulation of gene expression. A common link among all laminopathies may be a failure of stem cells to regenerate mesenchymal tissue. This could contribute to the connective tissue dysplasia seen in cutaneous asthenia.

Diffuse-regressive alterations and apoptosis of myocytes: Possible causes of myocardial dysfunction in HIV-related cardiomyopathy

Objective: To determine the frequency of cardiac alterations in necropsies of AIDS patients in pre-HAART era and better understand the pathogenesis of HIV-related cardiomyopathy. Design: Retrospective study of 94 complete necropsies. Method: Macroscopic, histopathologic (histochemical,immunohistochemical and in situ hybridization techniques) and ultra structural myocardial evaluation (23 cases). Results: Cardiac alterations were observed in 94.4%; 74% showed variable degrees of cardiac dilation not related to known cardiovascular diseases. Eighty-two percent (81.8%) of patients with biventricular dilation showed diffuse-regressive alterations (thinning and waving cardiomyocytes with increase of lipofuscin pigment granules). Myocarditis was diagnosed in 27 cases (28.7%), 16 (59.3%) of known etiology. The ultra structural study has revealed cardiomyocytes alterations (mitochondriosis, loss of myofibrils, increase in the amount of perinuclear-lipofuscin pigment granules) associated to activation signals of capillary-endothelial cells (enhancement of pseudopodia and transcellular channels). Cardiomyocytes` apoptosis was demonstrated at structural level in 10 (43.5%) patients; tumor necrosis factor alpha (TNF alpha) was detected in 17/18 cases. Conclusions: This pioneer study described the association of histopathological and ultra structural findings (thinning and waving cardiomyocytes with increase of lipofuscin pigment granules, mitochondriosis and loss of myofibrils) with different degrees of cardiac-chamber dilation probably representing a spectrum of alterations that would lead to myocardial dysfunction and development of HIV-related cardiomyopathy. Cardiomyocytes` apoptosis observed at ultra structural level and demonstration of TNF alpha associated to described alterations suggest that this cytokine plays an important role in both negative-inotropic effect and capacity to induce apoptosis through death receptor-controlled pathway. (C) 2008 Published by Elsevier Ireland Ltd.

Activated status of basophils in chronic urticaria leads to interleukin-3 hyper-responsiveness and enhancement of histamine release induced by anti-IgE stimulus

Background Basophils and mast cells are the main target cells in chronic idiopathic urticaria (CIU). Besides the basopenia, intrinsic defects of the anti-IgE cross-linking signalling pathway of basophils have been described in CIU. Objectives We sought to investigate the profile of expression of activation markers on basophils of patients with CIU and to explore the effect of interleukin (IL)-3 priming upon anti-IgE cross-linking stimuli through expression of activation markers and basophil histamine releasability. Methods Evaluation of the surface expression of Fc epsilon RI alpha, CD63, CD203c and CD123 on whole blood basophils of patients with CIU undergoing autologous serum skin test (ASST) was performed by flow cytometry. The effect of pretreatment with IL-3 in the anti-IgE response was analysed by the expression of basophil activation markers and histamine release using enzyme-linked immunosorbent assay. Results Blood basophils of patients with CIU were reduced in number and displayed increased surface expression of Fc epsilon RI alpha, which was positively correlated with the IgE serum levels. Upregulation of expression of both surface markers CD203c and CD63 was verified on basophils of patients with CIU, regardless of ASST response. High expression of IL-3 receptor on basophils was detected only in ASST+ patients with CIU. Pretreatment with IL-3 upregulated CD203c expression concomitantly with the excreting function of blood basophils and induced a quick hyper-responsiveness to anti-IgE cross-linking on basophils of patients with CIU compared with healthy controls. Conclusions Basophils of patients with CIU showed an activated profile, possibly due to an in vivo priming. Functionally, basophils have high responsiveness to IL-3 stimulation, thereby suggesting that defects in the signal transduction pathway after IgE cross-linking stimuli are recoverable in subjects with chronic urticaria.

Prevention and reversion of nonalcoholic steatohepatitis in ob/ob mice by S-nitroso-N-acetylcysteine treatment

Objective: To evaluate the role oral administration of S-nitroso-N-acetylcysteine (SNAC), a NO donor drug, in the prevention and reversion of NASH in two different animal models. Methods: NASH was induced in male ob/ob mice by methionine-choline deficient (MCD) and high-fat (H) diets. Two animal groups received or not SNAC orally for four weeks since the beginning of the treatment. Two other groups were submitted to MCD and H diets for 60 days receiving SNAC only from the 31(st) to the 60(th) day. Results: SNAC administration inhibited the development of NASH in all groups, leading to a marked decrease in macro and microvacuolar steatosis and in hepatic lipid peroxidation in the MCD group. SNAC treatment reversed the development of NASH in animals treated for 60 days with MCD or H diets, which received SNAC only from the 31(st) to the 60(th) day. Conclusions: Oral administration of SNAC markedly inhibited and reversed NASH induced by MCD and H diets in ob/ob mice.

Impact of pressure profile and duration of recruitment maneuvers on morphofunctional and biochemical variables in experimental lung injury

Objective: To investigate the effects of the rate of airway pressure increase and duration of recruitment maneuvers on lung function and activation of inflammation, fibrogenesis, and apoptosis in experimental acute lung injury. Design: Prospective, randomized, controlled experimental study. Setting: University research laboratory. Subjects: Thirty-five Wistar rats submitted to acute lung injury induced by cecal ligation and puncture. Interventions: After 48 hrs, animals were randomly distributed into five groups (seven animals each): 1) nonrecruited (NR); 2) recruitment maneuvers (RMs) with continuous positive airway pressure (CPAP) for 15 secs (CPAP15); 3) RMs with CPAP for 30 secs (CPAP30); 4) RMs with stepwise increase in airway pressure (STEP) to targeted maximum within 15 secs (STEP15); and 5) RMs with STEP within 30 secs (STEP30). To perform STEP RMs, the ventilator was switched to a CPAP mode and positive end-expiratory pressure level was increased stepwise. At each step, airway pressure was held constant. RMs were targeted to 30 cm H(2)O. Animals were then ventilated for 1 hr with tidal volume of 6 mL/kg and positive end-expiratory pressure of 5 cm H(2)O. Measurements and Main Results: Blood gases, lung mechanics, histology (light and electronic microscopy), interleukin-6, caspase 3, and type 3 procollagen mRNA expressions in lung tissue. All RMs improved oxygenation and lung static elastance and reduced alveolar collapse compared to NR. STEP30 resulted in optimal performance, with: 1) improved lung static elastance vs. NR, CPAP15, and STEP15; 2) reduced alveolar-capillary membrane detachment and type 2 epithelial and endothelial cell injury scores vs. CPAP15 (p < .05); and 3) reduced gene expression of interleukin-6, type 3 procollagen, and caspase 3 in lung tissue vs. other RMs. Conclusions: Longer-duration RMs with slower airway pressure increase efficiently improved lung function, while minimizing the biological impact on lungs. (Crit Care Med 2011; 39:1074-1081)

Prevalence and distribution of the GBV-C/HGV among HIV-1-infected patients under anti-retroviral therapy

Infection with GB virus C (GBV-C) or hepatitis G virus (HGV) is highly prevalent among HIV/AIDS patients. GBV-C/HGV viremia has not been associated with liver disease and seems to slow HIV disease progression. To study the GBV-C/HGV genotypes prevalence among HIV/AIDS patients and its association with HIV viral load (VL) and CD4+ lymphocyte counts. From February 2003 to February 2004, we analyzed 210 HIV-1-infected subjects who were on anti-retroviral therapy (ART). For 63 of them a PCR-nested to the non-coding 5` (5`NCR) region of the GBV-C/HGV was done, and for 49 a DNA direct sequencing was done. A phylogenetic analysis was performed by PHYLIP program. 63(30%) of the HIV-1-infected patients were co-infected with GBV-C/HGV. The phylogenetic analysis revealed the following genotypes (and respective relative frequencies): 1(10%), 2a (41%), 2b (43%), and 3 (6%). Co-infected patients presented lower HIV-1 VL and higher T CD4+ lymphocyte cells counts as compared with patients negative for GBV-C/HGV sequences (log = 4.52 vs. 4.71, p = 0.036), and T CD4+ lymphocyte counts (cells/mm(3) = 322.6 vs. 273.5, p = 0.081, respectively). T CD4+ cells counts equal to, or higher than, 200/mm(3) were significantly more common among co-infected patients than among HIV-infected-only patients (p = 0.042). The lowest T CD4+ cells counts were associated with genotype 1 and the highest with genotype 2b (p = 0.05). The GBV-C/HGV infection prevalence was 30% among HIV-1-infected subjects, and was associated with lower VL and higher CD4+ lymphocyte counts. GBV-C/HGV genotype 2b may be associated with better immunological response. Published by Elsevier B.V.

CpG-Induced Th1-Type Response in the Downmodulation of Early Development of Allergy and Inhibition of B7 Expression on T Cells of Newborn Mice

Several differences have been described between neonatal and adult immune responses. The predisposition in early life to Th2-type response or tolerance makes it a susceptible period for infections and allergic sensitization. The aim of this work was to evaluate the effects of CpG-containing oligodeoxynucleotides on neonatal and adult immunization with ovalbumin and Blomia tropicalis extract and compare the CpG effects on B and T cells of neonatal and adult mice. Mice that received CpG showed reduced immunoglobulin E (IgE) antibody production in both neonatal and adult periods, in parallel to increased IgG2a antibody levels. We observed that spleen cells of mice that received CpG in early life produced increased amounts of interferon-gamma upon anti-CD3 stimulation. Negative regulation of IgE response was more pronounced in adult than neonate mice; further, CpG decreased anaphylactic antiovalbumin IgG1 only in adults. Also, an upregulation of toll-like receptor 9 expression was detected in adult B cells, but not in neonatal, upon CpG stimuli. Neonatal B cells showed enhanced interleukin (IL)-10 expression and decreased IL-6 levels than adult B cells in response to CpG. When we analyzed in vitro activation of CD4+ T cells, an increased expression of B7 molecules on T cells in neonates was suppressed by CpG. Altogether, we verified qualitative and quantitative evidences regarding CpG effect on neonatal and adult allergens immunizations, which points to the importance of understanding neonatal immune system to establish immunomodulatory strategies for prevention of allergic diseases.

Immunogenicity and tolerability of a virosome influenza vaccine compared to split influenza vaccine in patients with sickle cell anemia

The immunogenicity and tolerability of virosome and of split influenza vaccines in patients with sickle cell anemia (SS) were evaluated Ninety SS patients from 8 to 34 years old were randomly assigned to receive either virosome (n = 43) or split vaccine (n = 47) Two blood samples were collected, one before and one 4-6 weeks after vaccination Antibodies against viral strains (2006) A/New Caledonia (H1N1), A/California (H3N2), B/Malaysia were determined using the hemagglutinin inhibition test Post-vaccine reactions were recorded over 7 days Seroconversion rates for HI NI, H3N2 and B were 65 1%. 60 4% and 83 7% for virosome vaccine, and 68 0%, 61 7% and 68 0% for split vaccine Seroprotection rates for HI NI, H3N2 e B were 100%. 97 6% and 69.7% for virosome. and 97 8%, 97 8% and 76 6% for split vaccine No severe adverse reactions were recorded Virosome and split vaccines in patients with sickle cell anemia were equally Immunogenic. with high seroconversion and seroprotection rates Both vaccines were well tolerated (C) 2009 Elsevier Ltd All rights reserved

Effects of Salivary Gland Homogenate from Wild-Caught and Laboratory-Reared Lutzomyia longipalpis on the Evolution and Immunomodulation of Leishmania (Leishmania) amazonensis Infection

We investigated the effects of Lutzomyia longipalpis salivary glands homogenate of wild-caught and laboratory-reared vectors on the lesion evolution and immunomodulation of the infection caused by Leishmania (Leishmania) amazonensis. To compare the effect of both salivary glands homogenate (SGH), C57BL/6 mice were inoculated Subcutaneously into the hind footpads or into the ear dermis with 10(6) promastigotes in the presence or not of SGH from wild-caught and laboratory-colonized sand flies. Comparing SGH groups, the lesion size was lower in mice co-inoculated with wild-caught SGH, as the parasitism and the infiltration of macrophages at the inoculation site. Wild-caught SGH also determined lower production of IL-4 and IL-10 but higher IL-12 levels compared with laboratory-reared SGH. Our findings address a probable bias by using SGH from laboratory-colonized sand flies instead of wild-caught vector SGH in studies concerning saliva effects. A possible mild influence of sand fly saliva in natural infections caused by Leishmania is also speculated, as infection is transmitted by wild and not by laboratory-reared vectors.