Risk factors for grade 3-4 liver enzyme elevation in HIV and hepatitis C coinfected patients on combination antiretroviral therapy

Although coinfection with hepatitis C (HCV) is an established risk factor for hepatotoxicity in HIV-positive patients receiving combination antiretroviral therapy (cART), specific variables that may be predictive of severe hepatotoxicity among co-infected patients receiving cART remain poorly defined. A retrospective cohort study of HIV/HCV coinfected adults from two HIV treatment centers covering the period between December 1998 and December 2003 was conducted to address this question. The primary endpoint of the study was the occurrence of grade 3 or 4 elevation of serum alanine aminotransferase (ALT) during follow-up and the primary predictors of interest were specific antiretrovirals. One hundred five coinfected patients receiving cART for a median of 70 months (interquartile range [IQR], 37, 83) were included in the analysis. Twenty-three (22%) patients developed a grade 3 or 4 increase in serum ALT at least once in follow-up. In univariate analysis, current receipt of lopinavir/ritonavir (LPV/r) (odds ratio [OR] 3.09, 95% confidence interval [CI] 1.14-8.34, p = 0.03), baseline ALT (OR 1.01, 95% CI 1.00-1.02, p = 0.004), and current use of boosting ritonavir (OR 2.84, 95% CI 1.16-7.00, p = 0.02) were significantly associated with a grade 3 or 4 increase in serum ALT, although most patients receiving boosting ritonavir were on lopinavir/ritonavir based regimens. Patients receiving LPV/r had been previously exposed to significantly more antiretrovirals (p < 0.0001), protease inhibitors (p < 0.0001), and nucleoside analogues (p = 0.0009) compared to the rest of the cohort. Further research to better clarify risk factors for hepatotoxicity in coinfected patients is warranted given the challenges in treating this population.

Autogeneic rna-electroporated CD40-ligand activated b-cells from hepatocellular carcinoma patients induce CD8+ T-cell responses ex vivo

Since dendritic cells (DCs) constitute only 0.1-0.5% of human peripheral blood mononuclear cells (PBMCs), and generation of DCs from monocytes or stem cells is difficult and expensive, we choose B-lymphocytes as an alternative, cost-effective source of antigen presenting cells (APC).

AIM

To induce specific CTLs response ex vivo by CD40L activated B-cells (CD40-B) transfected with hepatocellular carcinoma (HCC) total RNA.

METHODS

To induce CD40-B PBMCs of patients with HCC were isolated by Ficoll technique and cultured in RMPI 1640 supplemented with 10% fetal calf serum (FCS), sCD40L (2 microg/ml), recombinant human interleukin-4 (IL-4) (4 ng/ml). The expression of CD80 and CD86 was evaluated by flow cytometry. The level of interleukin-12 (IL-12) produced by cultured B-lymphocytes was measured using enzyme-linked immunosorbent assay (ELISA). HCC patient's T-lymphocytes were obtained from PBMCs cultured in RMPI 1640 supplemented with 10% FCS, 2 ng/mL IL-4 and 10 ng/ml IL-7. CD40-B transfected with tumor total RNA isolated from HCC cells were used to induce specific CTL proliferation. The level of IFN-gamma was measured using ELISA and the expression of CD8 was determined by FCAS. Specific cytotoxicity was measured using MTT method.

RESULTS

The results show that the activated B-lymphocytes were easily expandable and formed large clones, and a high expression of CD80/CD86 and a high IL-12 secretion by CD40-B was registered. CD40-B transfected with tumor total RNA can induce CTLs to express CD8 and generate IFN-gamma at high levels. Compared to the control group, the specific cytotoxicity of CTLs was up-regulated.

CONCLUSION

These findings demonstrate that CD40-B-cells electroporated with total RNA derived from carcinoma cells can be used as alternative APC for the induction of antigen-specific CD8(+) T-cell responses, which might be used in HCC immunotherapy.

Intensity Non-uniformity Correction of Magnetic Resonance Images Using a Fuzzy Segmentation Algorithm

Artifacts in magnetic resonance images can make conventional intensity-based segmentation methods very difficult, especially for the spatial intensity non-uniformity induced by the radio frequency (RF) coil. The non-uniformity introduces a slow-varying shading artifact across the images. Many advanced techniques, such as nonparametric, multi-channel methods, cannot solve the problem. In this paper, the extension of an improved fuzzy segmentation method, based on the traditional fuzzy c-means (FCM) algorithm and neighborhood attraction, is proposed to correct the intensity non-uniformity. Experimental results on both synthetic non-MR and MR images are given demonstrate the superiority of the algorithm.

Femtosecond laser inscription of optical waveguides in Bismuth ion doped glass

We report on the fabrication of high quality embedded channel waveguides inside Bi-doped silicate glass using femtosecond waveguide inscription. Waveguides are fabricated using both single and multi-scan fabrication techniques. Refractive index modifications of up to Deltan = 4.3 x 10(-3) are observed, allowing the fabrication of waveguides nearly mode-matched to telecom fibers. When optically pumped at 980 and 810 nm broadband fluorescence emission centered at 1.3 microm with a FWHM of up to 500 nm is detected.

Methylenetetrahydrofolate reductase C677T and A1298C variants do not affect ongoing pregnancy rates following IVF

BACKGROUND

There is concern that IVF could compromise normal imprinting and methylation of DNA. Methylenetetrahydrofolate reductase (MTHFR) regulates the flow of folic acid-derived, one-carbon moieties for methylation and is critical to early embryonic development. Therefore, we hypothesized that common polymorphisms in MTHFR could associate with IVF outcome.

METHODS

MTHFR C677T and A1298C polymorphism genotyping was performed on 374 subjects for this study, representing 197 couples undergoing IVF in a university setting from July 2005 to January 2006. Analysis of variance (ANOVA), chi-square and/or multivariate analyses were used to assess whether these polymorphisms are associated with embryo quality or with ongoing pregnancy or spontaneous abortion rates.

RESULTS

Allele frequencies for C677T ( p=0.67, q=0.33) and A1298C ( p=0.71, q=0.29) were in Hardy-Weinberg equilibrium. The C677T and A1298C variants, either alone or in combination, did not associate with embryo quality or short-term pregnancy outcome.

CONCLUSIONS

The common polymorphisms in MTHFR are not associated with embryo quality, as defined by cell number or fragmentation score, or with short-term pregnancy outcomes. Therefore, in our population in which women receive adequate folic acid, MTHFR genotypes are not informative in explaining IVF failure. Further studies, however, examining birth outcomes and the other enzymes in the folic acid pathway are warranted.