Giuseppe Pedrazzi

Restoration of HCV-specific T cell functions by PD-1/PD-L1 blockade in HCV infection: Effect of viremia levels and antiviral treatment

BACKGROUND/AIMS HCV-specific T cells in acute hepatitis C with subsequent chronic evolution are dysfunctional and most of them express PD-1. The aim of the study was to investigate to what extent the antiviral T cell function can be restored by reversing T cell exhaustion by PD-1/PD-L1 blockade and to assess whether this restoration is favored by IFN-alpha treatment. METHODS PD-1 and PD-L1 expression was studied on T cells and dendritic cells, respectively, of 14 patients with acute hepatitis C and different evolutions of infection. The effect of anti-PD-L1 was analyzed on proliferation, cytokine production and cytolytic activity of CD4 and CD8 T cells. RESULTS While PD-1 expression dropped concurrently with spontaneous or IFN-alpha induced HCV-RNA decline, PD-L1 levels on dendritic cells increased during IFN-alpha treatment. Anti-PD-L1 antibodies improved expansion and cytokine production but not the cytolytic activity of HCV-specific T cells. This restoration tended to be greater at lower levels of viremia and PD-1 expression and during PEG-IFNalpha treatment. CONCLUSIONS PD-1/PD-L1 blockade has an immunoregulatory activity which may synergize with the antiviral effect of IFN-alpha therapy and should be thus explored further in long-lasting chronic HCV infections in the perspective of improving the efficacy of available antiviral treatments.

PTEN status in advanced colorectal cancer treated with cetuximab

Background:Loss of phosphatase and tensin homologue deleted in chromosome 10 (PTEN) function in advanced colorectal cancer (CRC) may represent one of the resistance mechanisms to cetuximab by interfering with the epidermal growth factor receptor signal transduction pathway.Methods:PTEN expression tested by indirect immunofluorescence was evaluated both on primary (n=43) and on metastatic (n=24) sites in CRC patients treated with cetuximab.Results:The loss of PTEN expression tested on metastatic sites was negatively associated with response (100% progressive disease (PD) in PTEN-negative cases vs 30% PD in PTEN-positive cases; P<0.05), PFS (0.8 vs 8.2 months; P<0.001) and OS (2.9 vs 14.2 months; P<0.001).Conclusion:A potential role of PTEN in the anti-tumour activity of cetuximab could be hypothesised.

Calcium supplementation and prevention of preeclampsia: a meta-analysis

Background: Since the early 1980s, epidemiological evidence has suggested a connection between low calcium intake and preeclampsia The purpose of this meta-analysis is to summarize current evidence regarding calcium supplementation during pregnancy in predicting preeclampsia and associated maternal–fetal complications. Methods: Literature revision of all RCT (random allocation of calcium versus placebo) available in MEDLINE/PUBMED up to 2/29/2012 regarding calcium supplementation during pregnancy for preventing preeclampsia. We used the Mantel-Haenszel’s Method for four subgroup of patients: Adequate calcium intake; Low calcium intake; Low risk of preeclampsia; High risk of preeclampsia. We considered p < 0.05 as significant. Results: There is no consensus in Literature about: (1) the efficacy of calcium supplementation in the prevention of preeclampsia, (2) other/adverse/long-term effects of calcium supplementation in pregnancy. Conclusions: Preeclampsia is likely to be a multifactorial disease. However, inadequate calcium intake represents a factor associated with an increased incidence of hypertensive disease. The results of our meta-analysis demonstrate that the additional intake of calcium during pregnancy is an effective measure to reduce the incidence of preeclampsia, especially in populations at high risk of preeclampsia due to ethnicity, gender, age, high BMI and in those with low baseline calcium intake.

Natural killer cell phenotype modulation and natural killer/T‐cell interplay in nucleos(t)ide analogue‐treated hepatitis e antigen‐negative patients with chronic hepatitis B

Natural killer (NK) and hepatitis B virus (HBV)‐specific T cells are functionally impaired in chronic hepatitis B (CHB). Understanding to what extent nucleos(t)ide analogue (NUC) therapy can improve T‐ and NK‐cell responses is important in the perspective of immunomonitoring strategies for a safe and earlier NUC withdrawal and of novel combination therapies based on modulation of antiviral immunity. To gain further insights into T/NK‐cell interplay, we studied NK‐cell phenotype and function in hepatitis B e antigen–negative chronic HBV patients either untreated (25) or NUC treated (36 hepatitis B surface antigen [HBsAg]+ and 10 HBsAg–/hepatitis B surface antibody [anti‐HBs]+). Interferon‐gamma, interleukin‐2, and tumor necrosis factor alpha (TNF‐α) production by HBV‐specific T cells was also analyzed in NUC‐treated patients. NK cells from chronic naïve patients showed an “inflammatory” phenotype defined by increased expression of TNF‐related apoptosis‐inducing ligand (TRAIL), CD38, and Ki67 that significantly declined upon viremia suppression and alanine aminotransferase normalization induced by NUC therapy. Reversion to a quiescent NK‐cell phenotype was associated with restoration of the HBV‐specific T‐cell function. T‐ and NK‐cell responses showed an inverse correlation, with an opposite behavior in individual NUC‐treated patients. NK‐cell depletion as well as TRAIL and NKG2D pathway blockade induced a significant improvement of the HBV‐specific T‐cell function. Conclusions: NK cells can express regulatory activity on T cells in NUC‐treated patients with prevalent inhibition of CD4 T cells, likely needed to limit persistent T‐cell activation. NK‐cell phenotype is modulated by NUC therapy and its reversion to quiescence mirrors efficient HBV‐specific T‐cell responses. Thus, changes of NK‐cell phenotype may predict acquisition of antiviral control before anti‐HBs seroconversion and represent the groundwork for future studies aimed at assessing whether NK phenotyping can be translated into the clinical practice to guide NUC suspension.(Hepatology 2015;62:1697–1709)

NK cell phenotype modulation and NK/T cell interplay in nucleos(t)ide analogue treated HBeAg‐ patients with chronic hepatitis B

Natural killer (NK) and hepatitis B virus (HBV)‐specific T cells are functionally impaired in chronic hepatitis B (CHB). Understanding to what extent nucleos(t)ide analogue (NUC) therapy can improve T‐ and NK‐cell responses is important in the perspective of immunomonitoring strategies for a safe and earlier NUC withdrawal and of novel combination therapies based on modulation of antiviral immunity. To gain further insights into T/NK‐cell interplay, we studied NK‐cell phenotype and function in hepatitis B e antigen–negative chronic HBV patients either untreated (25) or NUC treated (36 hepatitis B surface antigen [HBsAg]+ and 10 HBsAg–/hepatitis B surface antibody [anti‐HBs]+). Interferon‐gamma, interleukin‐2, and tumor necrosis factor alpha (TNF‐α) production by HBV‐specific T cells was also analyzed in NUC‐treated patients. NK cells from chronic naïve patients showed an “inflammatory” phenotype defined by increased expression of TNF‐related apoptosis‐inducing ligand (TRAIL), CD38, and Ki67 that significantly declined upon viremia suppression and alanine aminotransferase normalization induced by NUC therapy. Reversion to a quiescent NK‐cell phenotype was associated with restoration of the HBV‐specific T‐cell function. T‐ and NK‐cell responses showed an inverse correlation, with an opposite behavior in individual NUC‐treated patients. NK‐cell depletion as well as TRAIL and NKG2D pathway blockade induced a significant improvement of the HBV‐specific T‐cell function. Conclusions: NK cells can express regulatory activity on T cells in NUC‐treated patients with prevalent inhibition of CD4 T cells, likely needed to limit persistent T‐cell activation. NK‐cell phenotype is modulated by NUC therapy and its reversion to quiescence mirrors efficient HBV‐specific T‐cell responses. Thus, changes of NK‐cell phenotype may predict acquisition of antiviral control before anti‐HBs seroconversion and represent the groundwork for future studies aimed at assessing whether NK phenotyping can be translated into the clinical practice to guide NUC suspension.(Hepatology 2015;62:1697–1709)

Ti-rich phlogopite from Mt. Vulture (Potenza, Italy) investigated by a multianalytical approach : substitutional mechanisms and orientation of the OH dipoles

Trioctahedral mica samples, collected at Cava St. Antonio (Mt. Vulture, Italy) were studied by combining electron-microprobe and C-H-N elemental analyses, single-crystal X-ray diffraction refinement, Mossbauer and Fourier transform infrared spectroscopies. Electron-microprobe analyses show the crystals to be quite homogeneous with TiO 2 ∼3 wt% and F ranging from 0.42 to 0.59 wt%. Quantitative analyses of H combined with ferric/ferrous ratios from Mossbauer data allowed reliable crystal-chemical formulae to be derived. The results suggest that the entry of both Ti 4+ and Fe 3+ in the structure occurs through R-oxy substitution mechanisms involving deprotonation at O(4). This inference is supported by X-ray structure-refinement results (notably the c cell-parameter, the off-centering of the M2 cation towards O(4), the bond-length distortions of the cis -M2 octahedron) obtained using anisotropic thermal parameters in space group C2/ m . The amount of oxy-substitutions from both electron-microprobe and X-ray data is in agreement with carbon-hydrogen-nitrogen analyses which give an average anion composition (OH 1.25 O 0.65 F 0.10 ). Polarized-light infrared spectroscopy shows a complex OH-stretching spectrum which is composed of several overlapping (at least five) components. These can be assigned to the main octahedral local configurations that are compatible with the chemical composition. Pleochroic Fourier transform infrared spectroscopy measurements done along the principal optical directions show that the O-H bond axis is tilted from [001] and provide the average orientation of the O-H dipole in the structure: O-H ⁁ α ∼ 23° and O-H ⁁ γ ∼ 56°.

Increased Levels of Inducible HSP70 in Cells Exposed to Electromagnetic Fields

Abstract Alfieri, R. R., Bonelli, M. A., Pedrazzi, G., Desenzani, S., Ghillani, M., Fumarola, C., Ghibelli, L., Borghetti, A. F. and Petronini, P. G. Increased Levels of Inducible HSP70 in Cells Exposed to Electromagnetic Fields. Radiat. Res. 165, 95–104 (2006). Because reports in the literature on the effects of electromagnetic fields (EMFs) on expression of the 70-kDa heat-shock protein (HSP70) are somewhat contradictory, we studied the influence of low-frequency EMFs on the accumulation of inducible HSP70 in several cell models. Some of the cell types tested showed increased levels of HSP70 protein when exposed for 24 h to 50 Hz, 680 μT EMFs. In endothelial cells, EMFs alone induced only a poor and transient activation of the heat-shock transcription factor 1 (HSF1); however, neither the level of HSP70 mRNA nor the synthesis of HSP70 appeared to be altered significantly. Accordingly, transfection experiments involving HSP70 promoter showed that gene transcription was not affected. We also noted a marked reduction in proteasome activities in cell extracts exposed to EMFs. Interestingly, the heat-shock-induced levels of HSP70 mRNA and protein were increased by a concomitant weak stressor like EMFs. Taken together, our results indicate that in EMF-exposed endothelial cells, HSP70 gene transcription and translation are unaffected; however, EMFs alone promoted accumulation of the inducible HSP70 protein, probably by increasing its stability, and it enhanced accumulation and translation of the heat-induced HSP70 mRNA when applied in concert with heat shock.

BNa–BLi solid-solution in A-site-vacant amphiboles: synthesis and cation ordering along the ferri-clinoferroholmquistite–riebeckite join

Abstract Amphiboles were hydrothermally synthesized at 500 °C and 4 kbar in the system Li2O-Na2OFeO- Fe2O3-SiO2-H2O, with nominal compositions along the riebeckite [□Na2Fe32+Fe23+Si8O22(OH)2]-ferri-clinoferroholmquistite [□Li2Fe32+Fe23+Si8O22(OH)2] join, where the exchange vector is NaLi-1 at the B-site. Experimental products were characterized by powder XRD and SEM-EDAX, confirming very high amphibole yield along the join (>95%, plus minor quartz). The XRD patterns can be indexed in C2/m, and the refined cell parameters show linear variation as a function of composition. For the BLi end-member, the IR spectrum shows a single sharp main band centered at 3614 cm-1, which is assigned to the FeFeFe-OH-A□ configuration. With increasing BNa in the mineral, this band broadens and shifts 4 cm-1 to higher frequencies. This effect can be attributed to the change in M4 site occupancy. Minor ANa (partial solid-solution toward arfvedsonite) is also observed with increasing sodium in the system. Mössbauer spectroscopy confirms the cation distribution provided by IR data, and shows that a small, but significant amount of Fe2+ occurs at M4 along the join. Infrared spectroscopy shows that the Li end-member has a very ordered structure, whereas intermediate compositions show local heterogeneities associated with the presence of two different B sites occupied by Na or Li.

Cation-site partitioning in Ti-rich micas from Black Hill (Australia): A multi-technical approach

The crystal chemistry of Ti-rich trioctahedral micas of plutonic origin, cropping out at Black Hill (South Australia) has been investigated by combining electron microprobe analysis, single crystal X-ray diffraction, Mössbauer spectroscopy and X-ray photoelectron spectroscopy. Chemical analyses have shown the samples taken to be quite homogeneous and Ti-rich (TiO2 ≈ 7 wt.%). Mössbauer investigation yielded Fe2+/Fe3+ ≈ 30. X-ray photoelectron spectroscopy analysis seems to suggest the occurrence of three Ti species: octahedral Tr4+(60%), octahedral Ti3+(26%), and tetrahedral Ti4+(14%). The analyzed sample belongs to the 1M polytype and the relevant crystal data from structure analysis are: a = 5.347(1) Å, b = 9.261(2) Å, c = 10.195(2) Å, β = 100.29°(1). Anisotropic structure refinement was performed in space group C2/m, and converged at R = 2.62, Rw = 2.80. Structural details (the c cell parameter, the off-center shift of the M2 cation towards 04, the bond-length distortions of the cis-M2 octahedron, the interlayer sheet thickness, the projection of K−O4 distance along c*, the difference outer-inner) support the occurrence of the Ti-oxy substitution (VIR2+ + 2(OH)− ⇌ Ti4+ + 202− + H2) in the sample. Analysis of structural distortions as a function of the Ti content revealed that the positions of the oxygens 03 and 04 are displaced in opposite senses along [100]. This produces an enlargement of the M1 site with respect to the M2 site and a shortening of the interlayer distance. This trend seems to be in common with other Ti-rich 1M micas of plutonic origin.

Maternal Hydration Therapy Improves the Quantity of Amniotic Fluid and the Pregnancy Outcome in Third-Trimester Isolated Oligohydramnios A Controlled Randomized Institutional Trial

Amniotic fluid is important for the maintenance of fetal well‐being; therefore, an amniotic fluid deficiency, ie, oligohydramnios, can have multiple impacts on the prognosis of the pregnancy. In some cases, there are no evident fetal or maternal causes, and the condition is called isolated oligohydramnios. The aim of our study was to validate maternal intravenous and oral hydration therapy as a means for improvement of isolated oligohydramnios in the third trimester of pregnancy.