Pretreatment serum interferon gamma inducible protein-10 as biomarker of fibrosis and predictor of virological response in genotype 4 hepatitis C virus infection.

OBJECTIVE: Assess the value of baseline interferon-γ-inducible protein-10 (IP-10) levels as a noninvasive maker of liver fibrosis and as a predictor of response to interferon therapy in HCV genotype 4 infected patients. METHODS: Eighty-four HCV genotype 4 infected patients were enrolled in this study. Degrees of liver fibrosis were determined and baseline IP-10 was measured in serum samples collected prior to initiation of treatment using the enzyme-linked immunosorbent assay. Patients were followed up for 1.5 year to assess their response to antiviral therapy. RESULTS: The baseline IP-10 levels were significantly correlated with the degree of fibrosis and had the ability to differentiate between patients with mild, moderate and advanced stages of fibrosis (F0-1: 95.24 ± 33.08 pg/ml, n = 25; F2: 158.70 ± 52.74 pg/ml, n = 37; F3-4: 357.45 ± 162.18 pg/ml, n = 22; P <0.001). Baseline IP-10 levels were significantly lower in patients achieved Early virological response (responders 134.80 ± 60.47 pg/ml, n = 60; non-responders 334.54 ± 168.94 pg/ml, n = 24, P <0.001). Also baseline IP-10 levels were significantly lower in patients who became HCV RNA negative at 24 weeks of therapy (179.52 ± 130.03 pg/ml, n = 78) than non-responders (352.33 ± 132.58 pg/ml, n = 6, P = 0.002). SVR was achieved in 58/68 (85.3%) patients while 10 patients were relapsed. Baseline IP-10 levels differs significantly between patients who achieved SVR at week 24 post therapy and relapsed patients (IP10 level: SVR, 173.52 ± 125.20 pg/ml, n = 58; Relapsed, 216.20 ± 67.72 pg/ml, n = 10, P = 0.021). CONCLUSION: Baseline IP-10 level independently predicts EVR, response at week 24 during therapy and SVR. It also differentiates patients with mild fibrosis from those with moderate and advanced fibrosis.

Water, sulfur dioxide and nitric acid adsorption on calcium carbonate: a transmission and ATR-FTIR study.

Calcium carbonate (CaCO3) is a reactive component of mineral dust aerosol as well as buildings, statues and monuments. In this study, attenuated total reflection (ATR) and transmission Fourier transform infrared spectroscopy (FTIR) have been used to study the uptake of water, sulfur dioxide and nitric acid on CaCO3 particles at 296 K. Under atmospheric conditions, CaCO3 particles are terminated by a Ca(OH)(CO3H) surface layer. In the presence of water vapor between 5 and 95% relative humidity (RH), water molecularly adsorbs on the Ca(OH)(CO3H) surface resulting in the formation of an adsorbed thin water film. The adsorbed water film assists in the enhanced uptake of sulfur dioxide and nitric acid on CaCO3 in several ways. Under dry conditions (near 0% RH), sulfur dioxide and nitric acid react with the Ca(OH)(CO3H) surface to form adsorbed carbonic acid (H2CO3) along with sulfite and nitrate, respectively. Adsorbed carbonic acid is stable on the surface under vacuum conditions. Once the surface saturates with a carbonic acid capping layer, there is no additional uptake of gas-phase sulfur dioxide and nitric acid. However, upon adsorption of water, carbonic acid dissociates to form gaseous carbon dioxide and there is further uptake of sulfur dioxide and nitric acid. In addition, adsorbed water increases the mobility of the ions at the surface and enhances uptake of SO2 and HNO3. In the presence of adsorbed water, CaSO3 forms islands of a crystalline hydrate whereas Ca(NO3)2 forms a deliquescent layer or micropuddles. Thus adsorbed water plays an important and multi-faceted role in the uptake of pollutant gases on CaCO3.