Soluble transferrin receptors and tissue oxygenation in non anaemic cystic fibrosis patients.

BACKGROUND: Chronic pulmonary disease and progressive tissue hypoxia are major causes of morbidity and mortality in cystic fibrosis (CF). Normally the body adapts to tissue hypoxia by increasing the red cell mass and decreasing the Hb-O(2) affinity. These adaptations are commonly observed in patients with cyanotic heart disease and individuals living at high altitude. However, patients with CF not only have an impaired erythroid response to hypoxia, but also are frequently anaemic. METHODS: In order to evaluate erythroid marrow activity and tissue oxygenation in 37 patients with CF we measured: the haematological and blood chemistry parameters; including red cell indices, ferritin, erythropoietin (Epo) and soluble transferrin receptors (sTfR) levels; arterial blood gases, P(50) and oxygen release to the tissues (O(2)(R)) and the 2,3-BPG levels. RESULTS: The main results showed that a) patients with CF have a mild degree of tissue hypoxia which is expressed by the moderately decreased of P(50) and O(2)(R) values and the relative increase of Epo level, b) 2,3-BPG synthesis in patients with CF is normal and c) sTfR levels are significantly increased (3-fold normal) in patients with CF compared to normal controls. CONCLUSIONS: The above observations indicate that erythroid marrow activity in patients with CF is increased.     

Association of TIMP-1 +372 SNP with digital ulcer manifestation in female systemic sclerosis patients

A candidate gene for TIMP-1 gene located on the X-chromosome (rs4898) was selected for a control case study to investigate a possible association of this SNP with the susceptibility to systemic sclerosis and its digit ulcer manifestation. A total of 461 individuals of Italian Caucasian origin (228 SSc patients and 233 healthy control subjects) were genotyped for TIMP-1 +372 T/C single nucleotide polymorphism rs4898. Subgroups were analyzed according to the presence or absence of digital ulcers. The CC genotype and C allele frequencies were significantly lower in female SSc patients than in controls (OR 0.53, CI 0.29-0.96, p=0.03 and OR 0.72, CI 0.53-0.98 p=0.04, respectively). CC genotypes frequency was lower also in female patients with ulcers than those without ulcers (OR 0.37, CI 0.14-1.00, p=0.03). Furthermore, CC genotype and C allele frequencies were lower also in female patients with ulcers in comparison to female healthy control subjects (OR 0.27, CI 0.10-0.70, p=0.004; OR 0.60, CI 0.40-0.89, p=0.01, respectively). The TIMP-1 rs4898 polymorphism may play a protective role in the susceptibility to SSC in females, and in particular to digital ulcer formation.     

Analysis of matrix metalloproteinase-9 gene polymorphism -1562 C/T in patients suffering from systemic sclerosis with and without ulcers

The objective of this study was to determine whether the matrix metalloproteinase-9 (MMP-9) rs3918242 single nucleotide polymorphism may confer susceptibility to systemic sclerosis (SSc) with and without ulcers in an Italian Caucasian population. The MMP-9 rs3918242 functional polymorphism was genotyped in 461 subjects of Italian Caucasian origin: 228 patients with SSc (92 with and 136 without ulcers) and 233 unrelated healthy individuals. The SNP under study was in Hardy-Weinberg equilibrium in the control population. Genotype and allele distributions between SSc patients, with or without ulcers, were not statistically significant (p>0.05). A significant increase of the genotype C/T was observed in male SSc patients without ulcers when compared to patients with ulcers (P=0.04). The MMP-9 rs3918242 functional polymorphism is not associated with susceptibility to SSc. However, the presence of the polymorphism may have a protective effect on the development of ulcers in SSc male patients.     

Erythroid marrow activity and functional anemia in patients with the rare interaction of a single functional a-globin and beta-globin gene

BACKGROUND AND OBJECTIVES: The degree of globin chain imbalance and tissue hypoxia are important determinants of clinical severity in thalassemia syndromes. Thus phenotypic expression may be modified by interaction of alpha- and beta-thalassemia defects, level and type of hemoglobin synthesized and oxygen release to the tissues. We evaluated hematology, erythroid marrow activity and functional anemia in patients with the rare interaction of a single a-globin gene and heterozygous beta-thalassemia (HbH/beta-thal trait). DESIGN AND METHODS: In 7 patients characterized by DNA analysis to have HbH disease genotypes with beta-thalassemia trait, we assessed hematologic findings, serum transferrin receptor (sTfR), serum erythropoietin (Epo), red cell 2,3-disphosphoglycerate (2,3-DPG) and whole blood oxygen releasing capability. RESULTS: Patients with HbH/beta-thal trait had moderate anemia, marked hypochromasia and microcytosis, normal or raised HbA2, and no electrophoretically/chromatographically detectable HbH. Epo and sTfR levels were significantly higher than in beta-thalassemia heterozygotes, but lower than in patients with HbH disease; 2,3-DPG levels were highest in HbH/beta-thal trait. Oxygen binding studies and simulations showed reduced oxygen affinity (P50) in HbH/beta-thal trait, resulting in increased oxygen release (O2R). INTERPRETATION AND CONCLUSIONS: Hematologic findings and bone marrow activity in patients with HbH/b-thal trait were consistent with the modified globin chain imbalance and hemoglobin synthesis expected from interaction of HbH disease with heterozygous b-thalassemia, although this rare complex genotype may elude diagnosis based on hematology alone. Significantly higher red cell 2,3-DPG levels were an unexpected finding, and the consequent increase in oxygen release capability resulted in a compensated functional anemia relative to hemoglobin levels.     

FOXP3, ICOS and ICOSL gene polymorphisms in systemic sclerosis: FOXP3 rs2294020 is associated with disease progression in a female Italian population

Systemic sclerosis (SSc), an autoimmune disorder, is characterized by vasculopathy, inflammation, progressive perivascular and interstitial fibrosis. Its pathogenesis is largely unknown, however strong evidences suggest that genetic predisposition may contribute to SSc development.Several gene polymorphisms involved in regulatory T cell function have been identified in many autoimmune diseases, including SSc. Moreover, dysregulation of co-stimulatory and/or co-inhibitory signals, including ICOS signalling, can lead to autoimmunity. The aim of the present study was to investigate the association of the FOXP3 rs2294020, ICOS rs6726035 and ICOSL rs378299 SNPs with both the susceptibility and the progression to SSc in an Italian case-series of patients.SNP genotyping results were successfully obtained from a total of 350 subjects including 166 individuals with SSc and 184 healthy controls. Although analysis tests did not show any significant associations between the SNPs under study and susceptibility to SSc, the occurrence of FOXP3 rs2294020 in female patients was associated with decreased time to progression from early to definite SSc (allelic model: HR = 1.43; CI = 1.03-1.99; p = 0.03; dominant model: HR = 1.54; CI = 1.04-2.28; p = 0.03). The inclusion of presence of ACA autoantibodies in the model did not significantly change the estimates. No conclusions can be drawn for the susceptibility to the disease or the time to progression in men due to the low statistical power. This study provides evidence of the association of rs2294020 with SSc evolution in female patients, modulating the time of progression from the diagnosis of early SSc to the diagnosis of definite SSc, while no effect on SSc susceptibility per se was found. rs2294020 may be considered a disease-modifying gene-variant rather than a disease-susceptibility SNP in SSc.     

Antimicrobial susceptibility of multidrug-resistant Gram negative bacteria to fosfomycin

We evaluated the antimicrobial activity of fosfomycin against a randomly selected sample of 30 Klebsiella pneumoniae, 30 Pseudomonas aeruginosa, and 30 Acinetobacter baumannii multidrug-resistant, clinical isolates from patients in a general tertiary care hospital in Athens, Greece. Standard laboratory methods were used for susceptibility testing to commonly used antibiotics and the detection of extended-spectrum-beta-lactamase (ESBL) and metallo-beta-lactamase (MBL) production. The minimum inhibitory concentration (MIC) of fosfomycin for each isolate was determined by the agar dilution method. All K. pneumoniae isolates were both ESBL and MBL producers; all P. aeruginosa isolates were ESBL producers. The K. pneumoniae strains had fosfomycin MICs distributed across a range of 8-64 microg/ml; MIC(50) was 16 microg/ml and MIC(90) 32 microg/ml. The fosfomycin MICs of the P. aeruginosa strains had a distribution across a range of 4 to over 512 microg/ml; MIC(50) was 32 microg/ml and MIC(90) 128 microg/ml. The fosfomycin MICs of the A. baumannii strains had a distribution across a range of 64 to over 512 microg/ml; MIC(50) was 256 microg/ml and MIC(90) more than 512 microg/ml. Although standardized fosfomycin MIC interpretative breakpoints for the species studied are lacking, the findings of our study support the idea that fosfomycin may be further investigated as one among a decreasing list of therapeutic options for the treatment of infections due to multidrug-resistant strains of, primarily, K. pneumoniae and, secondly, P. aeruginosa.     

Immunolocalization of E-cadherin and alphaE-catenin in rat parotid acinar cell under chronic stimulation of isoproterenol

E-cadherin and alphaE-catenin were localized in normal and chronically isoproterenol-treated acinar cells of rat parotid gland by means of immunogold labelling of Lowicryl embedded sections. Immunostaining of both experimental groups with polyclonal antibodies to E-cadherin and alphaE-catenin was mainly restricted to the areas of adherens junctions. Surprisingly, in isoproterenol-treated cell alphaE-catenin was also found on the secretory granules periphery and appeared to encircle a secretory vesicle. In isoproterenol-induced cell hyperproliferation, the maintened presence of adherens junctions components, such as E-cadherin and alphaE-catenin molecules, should be an essential prerequisite for tissue integrity. Our data suggest the presence of a correlation between the organization of actin and the localization of alphaE-catenin in the chronically isoproterenol-treated acinar cell of rat parotid gland.     

Biological therapy downregulates the heterodimer S100A8/A9 (calprotectin) expression in psoriatic patients

The pathophysiology of psoriasis is very complex and involves an interplay between immune cells and keratinocytes. The keratinocyte production of calprotectin (S100A8/A9), induced by the inflammatory psoriatic milieu, may be involved in initiating immune cell invasion, as well as in propagating inflammation. However, the exact role of calprotectin in psoriasis remains unclear. Therapeutic approaches utilizing adalimumab, etanercept and ustekinumab are widely used in psoriatic treatment, but their anti-inflammatory mechanisms are not fully understood. The aim of this study was to investigate, by immunohistochemical analysis, the expression of the heterocomplex S100A8/A9 in lesional skin from psoriatic patients undergoing biological therapy with adalimumab, etanercept or ustekinumab. Our results showed that S100A8/A9, absent or present at very low level in skin biopsies from healthy subjects, is dramatically upregulated in each epidermal layer from psoriatic patients. Interestingly, calprotectin was mainly localized in keratinocyte nuclei from psoriatic patients, suggesting a role of S100A8/A9 in keratinocyte nuclear function. Furthermore, we have shown that the biological treatment induced a drastic reduction of S100A8/A9 expression in skin biopsies from treated patients, correlating with PASI reduction. Our results suggest that calprotectin may play a crucial role as a significant marker of inflammation in psoriasis, and that its reduction of expression may be considered a favourable prognostic marker in psoriasis.