Telbivudine on-treatment HBsAg loss in naive HBeAg negative chronic hepatitis B: a case report and brief review of the literature.

The authors describe the clinical case of a naive patient with chronic hepatitis HBV-related (CHB) HBeAg negative, treated with Telbivudine (LdT) 600mg/day. After six months of treatment, as well as it determines rapid, profound and sustained suppression of HBV replication, LdT induced a progressive decline of HBsAg serum level and HBsAg loss, probably through an immune modulator effect. Recent studies have indicated the possible action of LdT on the immune system and specifically it would be able to stimulate Th1 lymphocyte subpopulation by increasing their cytokines production, thus playing a major role in cleaning the HBV infection. This aspect appears to be of much interest in clinical practice, because on-treatment HBsAg rapid decline >1 log10 IU/mL during the first year of treatment is highly predictive for future HBsAg clearance and CHB resolution.

Diagnostic and prognostic value of alpha-fetoprotein, des-γ-carboxy prothrombin and squamous cell carcinoma antigen immunoglobulin M complexes in hepatocellular carcinoma.

The hepatocellular carcinoma (HCC) is one of the most common malignant tumors. It carries a poor survival rate and has an increasing incidence worldwide. In most cases, HCC is diagnosed at a late stage. Therefore, the prognosis of patients with HCC is generally poor and has a less than 5% 5-year survival rate. The aim of this study was compare the accuracy of α-fetoprotein (AFP), des-γ- carboxy prothrombin (DCP), squamous cell carcinoma antigen-immunoglobulin M complexes (SCCA-IgM Cs) in the early diagnosis and in the prognosis of HCC. A literature search identified the markers for hepatocellular carcinoma. A search of the literature was made using cancer literature and the PubMed database for the following keywords: "markers and HCC", "α-fetoprotein (AFP) and HCC", "Des-γ-carboxy prothrombin"(DCP) and HCC, "squamous cell carcinoma antigen-immunoglobulin M complexes" (SCCA-IgM Cs). Despite the large number of studies devoted to the immunohistochemistry of HCC, at the present time, the absolute positive and negative markers for HCC are still lacking, and even those characterized by very high sensitivity and specificity do not have an universal diagnostic usefulness. In conclusion none of the three biomarkers (AFP, DCP, SCCA-IgM Cs) is optimal. According to recent reviews, these biomarkers should be measured simultaneously and in combination with imaging techniques to increase the sensitivity, specificity, diagnostic accuracy and to make a reliable prognosis. Currently the recommended screening strategy for patients with cirrhosis includes the determination of serum AFP levels and an abdominal ultrasound every six months to detect HCC at an earlier stage.

Meaning of elevated CA 19-9 serum levels in chronic hepatitis and HCV-related cirrhosis.

AIM: Carbohydrate 19-9 antigen (CA 19-9) has been used in the diagnosis and follow-up of gastrointestinal tumors. However, a remarkable reduction of specificity has been described in subjects with chronic diseases. Elevated CA 19-9 serum levels have been described in non neoplastic liver diseases, such as hepatic cirrhosis, where they correlate with the fibrosis grade and the disease severity. The aim of the study is to evaluate CA 19-9 levels in chronic hepatitis patients (CH) and hepatic cirrhosis patients, Hepatitis C Virus (HCV)-correlated. Our goal was to establish whether elevated CA 19-9 levels can be considered a non casual event in chronic liver disease and whether a correlation can be found between CA 19-9 levels and the severity of the disease. METHODS: 116 patients have been recruited (76 m, 40 f, average 54 years); 56 patients were affected by CH and 60 by hepatic cirrhosis (Child A). All patients were HCV+, genotype 1b. Patients positive to CA 19-9 high levels were subjected to abdominal echography, EGDS, colonscopy, abdominal CT. RESULTS: Fifty two percent presented high levels of CA 19-9. None was affected by intestinal or pancreatic neoplasia, or colestatic icterus. CA 19-9 levels were elevated in 46% of patients with chronic hepatitis, and in 54% in patients with hepatic cirrhosis. Furthermore, CA 19-9 levels in hepatic cirrhosis compared to CA 19-9 levels in chronic hepatitis was statistically significant (P>0.007). CONCLUSION: Increased serum levels of CA 19-9 are frequent in chronic viral hepatitis; this often does not indicate a contemporary neoplastic disease and correlates in a statistically significant way (P>0.007) with the severity of the disease.

[A rare case of drug-induced hepatitis]. / Un raro caso di epatite acuta da farmaci.

This paper describes a case of drug-induced hepatitis that onset in a patient who was hospitalised in our department after administration of calcium heparin. The rarity of the case was shown not only by the very short time elapsed between cause (drug administration) and effect (bio-humoral changes detected), but also by the histology results of the liver biopsy. This latter confirmed that mechanisms of idiosyncrasy, which may cause liver cell necrosis, can occur after administration of any drug.

Synthesis filter bank optimization in two-dimensional separable subband coding systems.

Subband coding is a popular and well established technique used in visual communications, such as image and video transmission. In the absence of quantization and transmission errors, the analysis and synthesis filters in a subband coding scheme can be designed to obtain perfect reconstruction of the input signal, but this is no longer the optimal solution in the presence of quantization of the subband coefficients. We presuppose the use of a two-dimensional (2-D) separable subband scheme and we address the problem of designing, for a given analysis filter bank and assuming uniform quantization of the subband coefficients, the set of row and column synthesis filters that minimize the mean squared reconstruction error at the output of the subband system. Since the corresponding optimization problem is inherently nonlinear, we propose a suboptimal solution that extends a one-dimensional (l-D) optimal filter design procedure, already presented in the literature, to a 2-D separable synthesis filter bank. The separable 2-D extension is not trivial, since the processing in one direction, e.g., the rows, alters the statistics of the signals for the design of the filters in the other direction, e.g., the columns. To further simplify the filter design, we propose to model the input image as a 2-D separable Markov process plus an additive white component. Several design examples using both synthetic signals and real world images are presented, showing that the filters designed using the proposed technique can give a significant gain with respect to the perfect reconstruction solution, especially when the dither technique is used for quantization. The simulation results also show that the proposed image model can be conveniently used in the synthesis filter design procedure.

Hybrid vector quantization for multiresolution image coding.

In this correspondence, we propose a coding scheme that exploits the redundancy of the multiresolution representation of images, in that blocks in one subimage are predicted from blocks of the adjacent lower resolution subimage with the same orientation. The pool of blocks used for prediction of a given subband plays the role of a codebook that is built from vectors of coefficients inside the subband decomposition itself. Whenever the prediction procedure does not give satisfactory results with respect to a target quality, the block coefficients are quantized using a geometric vector quantizer for a Laplacian source.

Image coding by block prediction of multiresolution subimages.

The redundancy of the multiresolution representation has been clearly demonstrated in the case of fractal images, but it has not been fully recognized and exploited for general images. Fractal block coders have exploited the self-similarity among blocks in images. We devise an image coder in which the causal similarity among blocks of different subbands in a multiresolution decomposition of the image is exploited. In a pyramid subband decomposition, the image is decomposed into a set of subbands that are localized in scale, orientation, and space. The proposed coding scheme consists of predicting blocks in one subimage from blocks in lower resolution subbands with the same orientation. Although our prediction maps are of the same kind of those used in fractal block coders, which are based on an iterative mapping scheme, our coding technique does not impose any contractivity constraint on the block maps. This makes the decoding procedure very simple and allows a direct evaluation of the mean squared error (MSE) between the original and the reconstructed image at coding time. More importantly, we show that the subband pyramid acts as an automatic block classifier, thus making the block search simpler and the block matching more effective. These advantages are confirmed by the experimental results, which show that the performance of our scheme is superior for both visual quality and MSE to that obtainable with standard fractal block coders and also to that of other popular image coders such as JPEG.