Eosinophils release extracellular DNA traps in response to Aspergillus fumigatus

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Physicochemical, mechanical, and biological properties of bone cements prepared with functionalized methacrylates

Bone cements prepared with methyl methacrylate (MMA) as a base monomer and either methacrylic acid (MAA) or diethyl amino ethyl methacrylate (DEAEMA) as comonomers were characterized in terms of curing behavior, mechanical properties, and their in vitro biocompatibility.The curing time and setting temperature were found to be composition dependent while the residual monomer was not greatly affected by the presence of either acidic or alkaline comonomers in the bone cements. For samples with MAA comonomer, a faster curing time and higher setting temperature were observed when compared to the cement with DEAEMA comonomer.In terms of mechanical properties, the highest compressive strength was exhibited by formulations containing MAA, while the highest impact strength was shown by the formulations prepared with DEAEMA. There were no differences observed between the two formulations for tensile, shear, and bending strength values. Similarly, fatigue crack propagation studies did not reveal differences with the addition of either DEAEMA or MAA.No differences were observed in the initial number of attached primary rat femur osteoblasts on the different bone cements and positive controls. However, after 48 h there was a reduced proliferation in the cells grown on bone cements containing MAA.     

Activation of caspase-8 triggers anoikis in human neuroblastoma cells

Cells require appropriate interaction with extracellular matrix proteins mediated by integrins to grow, differentiate and survive. Many cell types including nervous cells undergo anoikis, a substrate-dependent apoptosis, when adhesion is impaired. Resistance of tumors to cytotoxic drugs is probably due to disturbed apoptosis programs. The proteolytic enzymes caspases are the main executioners of apoptosis. It was reported that caspase-8 expression is deficient in some neuroblastoma cells. We demonstrated that human neuroblastoma cell line SK-B-BE, differentiated with retinoic acid, expressed caspases 3, 8 and 9. Caspases 8 and 3, but not caspase-9 were activated in SK-N-BE cells cultured in suspension or on aspecific adhesive substrate. Cell positive to caspase-8 were classified into four stages, by morphometric and densitometric parameters. The use of the specific caspase-8 inhibitor Z-IETD-FMK dramatically reduced apoptosis, demonstrating that caspase-8 is the upstream initiator caspase during SK-N-BE cells anoikis. Among matrix proteins, type I collagen is the most effective and fibronectin the least in delaying anoikis. The activation of caspases 8 and 3 by unligated integrins was dependent on the state of neuronal differentiation, since the most differentiated cell was the most vulnerable to anoikis. These data show that activation of caspase-8 is specifically required to promote anoikis in SK-N-BE neuroblastoma cells.     

Noninvasive methods for the detection of upper and lower airway inflammation in atopic children

BACKGROUND: Exhaled nitric oxide (FE(NO)) and exhaled breath condensate (EBC) are noninvasive methods to assess inflammation. OBJECTIVE: To investigate the role of the FE(NO) and of the EBC pH and IL-5 levels in atopic children. METHODS: We evaluated oral and nasal FE(NO) and the pH and IL-5 of oral and nasal EBC in children with atopic dermatitis (AD; n = 18), allergic rhinitis (AR; n = 18), intermittent asthma (n = 21), moderate persistent asthma (n = 18), and healthy controls (HCs; n = 16). RESULTS: Oral FE(NO) was significantly increased in asthma, whereas the nasal values were increased in AR and asthma in comparison with HCs. The pH of oral EBC was lower in AD and asthma than in AR and HCs, whereas the nasal levels were lower in AD, AR, and asthma than in HCs. The oral IL-5 was higher in AD, AR, and asthma in comparison with HCs, whereas the nasal IL-5 concentrations were higher in asthma and AR than in HCs. In AR, the nasal FE(NO) correlated with the IL-5 values and with the disease duration. In intermittent asthma, oral and nasal pH inversely correlated with the exacerbations, whereas in moderate asthma, the nasal IL-5 positively correlated with exacerbations. In AD, the oral and nasal IL-5 positively correlated with the serum IgE. CONCLUSION: These markers of nasal and bronchial inflammation, accessible with noninvasive techniques, might be useful to identify patients with uncontrolled diseases and to verify the usefulness of new therapeutic approaches. CLINICAL IMPLICATIONS: These markers are useful tools to monitor the upper and lower airway inflammation in atopic children.     

Adjuvant effect of Lactobacillus casei in a mouse model of gluten sensitivity

Probiotic strains have been reported to exert immunomodulatory activities in the gut-associated lymphoid tissue. In this study we explored the effect of Lactobacillus casei in transgenic mice expressing the human DQ8 heterodimer, a HLA molecule linked to Celiac Disease (CD). DQ8 mice, mucosally immunized with the gluten component gliadin, mounted an intestinal Th1-like response as observed in CD, without developing enteropathy. Co-administration of L. casei in sensitized mice specifically enhanced the gliadin-specific response mediated by CD4(+) T cells. Notably, both a strong increase of the gliadin-specific IFNgamma expression and a pro-inflammatory polarization of the cytokine milieu in the small intestinal mucosa were associated to the presence of the probiotic strain. However, this condition did not bring on any mucosal alteration. These findings suggest that the gliadin-specific enteropathy is not merely related to the HLA DQ8-restricted massive production of IFNgamma, but additional parameters are involved. Moreover, our data imply that the intrinsic adjuvanticity of L. casei can be exploited to further enhance both mucosal and systemic T cell-mediated responses.     

Reliable typing of systemic amyloidoses through proteomic analysis of subcutaneous adipose tissue

Considering the important advances in treating specific types of systemic amyloidoses, unequivocal typing of amyloid deposits is now essential. Subcutaneous abdominal fat aspiration is the easiest, most common diagnostic procedure. We developed a novel, automated approach, based on Multidimensional Protein Identification Technology, for typing amyloidosis. Fat aspirates were obtained from patients with the most common systemic amyloidoses (ALλ, ALκ, transthyretin, and reactive amyloidosis), with Congo red score more than or equal to 3+, and nonaffected controls. Peptides from extracted and digested proteins were analyzed by Multidimensional Protein Identification Technology. On semiquantitative differential analysis (patients vs controls) of mass spectrometry data, specific proteins up-represented in patients were identified and used as deposit biomarkers. An algorithm was developed to classify patients according to type and abundance of amyloidogenic proteins in samples; in all cases, proteomic characterization was concordant with fibril identification by immunoelectron microscopy and consistent with clinical presentation. Our approach allows reliable amyloid classification using readily available fat aspirates.     

Severe liver disease is caused by HBV rather than HCV in children with hematological malignancies

Patients receiving chemotherapy experience exacerbations of chronic hepatitis B (HBV) or hepatitis C (HCV) viral infections. We examined the pattern of liver disease induced by these infections in 92 children and adolescents with elevated transaminases (median age: 9 years). This included 76 with hematological malignancies (55 ALL, 15 NHL and six Hodgkin's disease) and 16 with thalassemia major. Liver disease was graded: A--occasional hypertransaminemia, B--persistent hypertransaminemia, C--severe hepatitis without encephalopathy, D--fulminant hepatic failure (FHF) and death. Screening included HBsAg, anti-HCV antibody, HBV-DNA and HCV-RNA: 26 had liver biopsies. A total of 60 (79%) patients with malignancies were HBsAg and/or HBV-DNA(+)(genotype D-E) and 47 (62%) were anti-HCV and/or HCV-RNA(+); 33 were coinfected with HBV and HCV. Grade A (n=24) included 16 with HCV and 12 with HBV (six coinfected); 18 with HBV and 11 with HCV (10 coinfected) were graded B (n=22). All grade C (n=25) had HBV with 16 HCV coinfected. FHF and death occurred in five HBV-DNA(+) patients, in four within a month of i.v. methotrexate. Patterns C and D were associated with HBsAg and HBV-DNA (P=0.001 and P<0.001, respectively). In all, 70% of HBV-infected children suffered chemotherapy-associated flares. None of the thalassemics had severe hepatitis exacerbations; 94% had HCV markers with none HBV-DNA(+). One died of progressive cirrhosis. CONCLUSIONS: Children with hematological malignancies have worse liver disease when associated with chronic HBV. FHF occurred in HBsAg/HBV-DNA(+) children following i.v. methotrexate. Early recognition of hepatic dysfunction in HBV carriers is essential in order to reduce incidence of life-threatening complications.     

Evaluation of Hypertension in Children

Hypertension is an important public health problem, and increasingly children are being diagnosed with primary hypertension. As the list of secondary causes of hypertension is extensive, pediatric practitioners increasingly need to decide on investigations needed for evaluating children presenting with high blood pressure. The differentiation between primary and secondary hypertension is paramount to understanding this important health issue, since many forms of secondary hypertension require specific treatment. The review evaluates the current available guidelines and practice patterns for evaluating children with elevated blood pressure. The review also aims to provide a framework for cost-effective evaluation strategies for children with elevated blood pressure based on current recommendations and evidence.