Liver MR imaging: 1.5T versus 3T

This article focuses on technical challenges in transferring 1.5T liver protocols to 3T systems and the overall comparison of MR sequences, highlighting the advantages and disadvantages of imaging at the higher field strength. An important benefit is the capacity of acquiring high-quality, thin-section postgadolinium T1-weighted three-dimensional gradientecho sequences, most clinically relevant for the detection and characterization of small hypervascular malignant diseases. Further research and development is necessary to overcome disadvantages, such as with in- and out-of phase T1-weighted gradient-echo sequences, and to minimize artifacts that appear at 3T.     

Experimental evaluation of 3-dimensional kinematic behavior of the cruciate ligaments

PURPOSE: The purpose of this study was to evaluate a low-cost and easily reproducible technique for biomechanical studies in cadavers. In this kind of study, the natural effect of loading of the joint and shear forces are not taken into account. The objective is to describe the plastic deformation of the ligaments into 3-dimensional space. METHOD: For 18 intact human cadaver knees, the cruciate ligaments were divided into 3 fiber bundles, the tibial or femoral fixation points were marked, and 2 perpendicular different x-ray exposures were performed, thus obtaining radiographs of spatial projections of the bundle in 3 anatomic planes (frontal, sagittal, and transversal). From the measurements made on the x-ray films, we obtained the average distance between the 2 fixation points of the cruciate ligaments on the tibia and the femur at 4 different flexion angles. RESULTS: The distance between the fixation points of the medial and lateral fiber bundles of the cruciate ligaments did not change significantly during movement. There were, however, significant variations (P < .05) in the distance between the fixation points of the posterior fiber bundles of the anterior cruciate ligament and the anterior fiber bundles of the posterior cruciate ligament. CONCLUSIONS: This technique was efficient for demonstrating the plastic deformability of the cruciate ligaments. The results proceeding from this type of study can assist in the planning of physical rehabilitation programs.     

Factors associated with the development of cirrhosis in patients with HCV chronic infection

BACKGROUND/AIMS: The natural history of chronic hepatitis C virus (HCV) infection still has some details to be established, namely in what concerns progression to hepatic cirrhosis (HC). The study aims to define predictive factors for progression to HC in patients with HCV chronic infection. METHODOLOGY: A cross-sectional study was performed on 129 patients consecutively submitted to liver biopsy. Thirty-six percent (n=46) had HC at histological evaluation. RESULTS: Patients with HC did not show statistically significant differences on gender, viruses genotypes, alcohol consumption or proportion of positivity to markers of previous hepatitis B virus (HBV) infection - anti-HBc/anti-HBs+. Patients with HC seem to have had their infection sporadically (50%) or post-transfusion (35%) -p=0.052, and iv drugs addiction was related to non-HC patients (39%) -p=0.006. Age at infection, time of infection and positivity for anti-HBc/anti-HBs were factors independently related to HC (multivariate analysis). Patients older than 40 years by the time of infection [OR=4.5 (95% CI=1.9-10.8], those with less than 5 years of time of infection [OR=4.2 (95% CI=1.6-10.8)], and patients with previous HBV infection [OR=2.51 (1.00-6.69)] are at higher risk for HC. CONCLUSIONS: We argue that older patients, with a shorter time interval between HCV infection and diagnosis, and namely those with markers for previous HBV infection represent patients with higher risk for progression to hepatic cirrhosis.     

The HLA-G 14-base pair deletion allele and the deletion/deletion genotype are associated with persistent HBe antigenemia in chronic hepatis B infection

Background and aims: HLA-G has well-recognized immunomodulatory properties, and this molecule is frequently expressed in the livers of hepatitis B virus (HBV)-infected patients. Because the HLA-G 14 bp-insertion/deletion polymorphism (rs371194629) has been associated with the magnitude of HLA-G expression, we evaluated this polymorphism in the recognized evolutionary forms of chronic HBV infection. Methods: We studied 196 chronic HBV-infected patients (118 HBeAg-negative chronic hepatitis, 53 HBeAg-positive chronic hepatitis and 25 inactive carriers exhibiting low levels of serum HBVDNA and persistently normal ALT levels), and 202 healthy individuals. Chronic hepatitis HLA-G typing was performed using PCR-amplified DNA hybridized with specific primers. Results: The frequencies of the insertion/deletion alleles and genotypes were very similar in patients and controls. After patient stratification according to the evolutionary form of the chronic HBV infection, the frequencies of the deletion allele (P = 0.0460; OR = 1.26; 95%CI = 1.01–1.45) and of the deletion/deletion genotype (P = 0.0356; OR = 2.08; 95%CI = 1.05–4.09) were overrepresented in HBeAg-positive patients when compared to HBeAg-negative patients. No differences were observed when HBV inactive carriers were compared to HBeAg-negative chronic hepatitis patients. Conclusions: Because the 14-bp deletion allele has been associated with increased HLA-G production and because HLA-G may down regulate the cytotoxic activity of TCD8 and NK cells, patients exhibiting the 14-bp deletion allele at single or double doses are at increased risk for developing chronic forms of HBV associated with persistent viremia and worse prognoses.     

Regular consumption of fruits and vegetables by university students in Rio Branco, Acre State, Brazil: prevalence and associated factors

This cross-sectional study with university students examined the prevalence of regular consumption of fruits and vegetables and associated factors among students at a Federal university in Rio Branco, Acre State, Brazil. 863 undergraduates were interviewed in 2010. Overall prevalence of regular consumption of fruits and vegetables was 14.8%. Factors associated with regular consumption of fruits and vegetables were: socioeconomic classes A and B (PR = 1.70; 95%CI: 1.10-2.62), living with a partner (PR = 1.53; 95%CI: 1.02-2.29), regular physical activity (PR = 1.69; 95%CI: 1.11-2.56), and consumption of fast food twice a week or less (PR = 1.49; 95%CI: 1.04-2.13). A minority of the students met the recommendation to consume fruits and vegetables 5 or more days a week. Regular fruit and vegetable consumption was associated with socioeconomic status and healthy habits such as physical exercise and low consumption of fast food.     

Alpha-interferon improves liver fibrosis in chronic hepatitis C: clinical significance of the serum N-terminal propeptide of procollagen type III

Our objective was to estimate the effect of interferon (IFN) on the evolution of fibrosis in chronic hepatitis C and the significance of the N-terminal propeptide of procollagen type III (PIIIP) as a marker of fibrogenesis. One hundred seventeen patients, 72 male (61%) and 45 female (39%), with a mean age of 40.7 ± 11.9 years were treated with 2b-IFN, 3 to 5 MU, for 12 months: sustained responders (SR = 44), relapsers (RR = 35), and nonresponders (NR = 38). Liver biopsies were performed before treatment and 1 year after cessation of IFN for evaluation of the histological activity index (HAI). Serum PIIIP was obtained at the time of liver biopsy, at the beginning, during, and end of therapy and during the follow-up. The normal value in 29 healthy individuals was 0.37 ± 0.18 U/L. Staging was reduced in 58% of SR, 12.5% of RR, and 11.5% of NR. There was a correlation between PIIIP and the HAI before (n = 71, r _s = 0.41, P < 0.0004) and after IFN (n = 71, r _s = 0.58, P < 0.0001). The SR had a better improvement in grading (90.3%; P < 0.05) and staging (58%; P < 0.001). The correlation of the HAI parameters with the variation of PIIIP showed significance only for fibrosis (r _s = 0.36, P < 0.002) and portal inflammation (r _s = 0.35, P < 0.01). PIIIP normalized only in patients whose fibrosis improved (P < 0.01). At the end of therapy, PIIIP had a predictive value in the distinction of SR from RR (PPV, 64; PNV, 55.6). During the follow-up, PIIIP remained lower in SR compared with RR and NR (P < 0.002). The response to -IFN improved liver inflammation and fibrosis. Serum PIIIP is a useful noninvasive method to evaluate serially fibrogenesis in chronic hepatitis C treated with IFN.