Genotype 1 of hepatitis C virus increases the risk of major depression: a 12-week prospective study.

OBJECTIVE: Depressive symptoms have been frequently observed in association with immune activation. We prospectively evaluate depressive symptoms and risk factors for major depression in patients with hepatitis C virus treated with antiviral combined therapy. METHODS: Fifty patients were assessed during 1 year; the structured diagnostic interview - Mini International Neuropsychiatric Interview - was used to screen psychiatric disorders at the baseline and during the 4th and 12th week of antiviral therapy. STATISTICAL ANALYSIS: generalized estimating equations and pairwise comparisons with Bonferroni adjustment. RESULTS: In our sample the prevalence of the Genotype 1 was 42%, and the pegylated interferon alpha plus ribavirin was the most prevalent treatment used for hepatitis C (86%). We found increased risk of depression in the 4th week (34%) but not in the 12th week (24%) compared with baseline values (20%) (P=0.040). In addition, we found differences between depression prevalence and hepatitis C genotypes, with higher odds in the 4th week compared to the baseline and 12th week [OR: 2.1(1.15-2.9); P=0.040]. Patients with the Genotype 2/3 had significantly lower odds of presenting depression compared to the Genotype 1 [OR: 0.3 (0.1-0.9); P=0.030]. CONCLUSION: This study provides evidence for an association between hepatitis C genotype and major depression, showing that besides immune activation, the Genotype 1 is associated with increased risk for psychiatric symptoms during the follow-up.

Polyvinyl alcohol hydrogel irradiated and acetalized for osteochondral defect repair: mechanical, chemical, and histological evaluation after implantation in rat knees.

Polyvinyl Alcohol (PVA) hydrogel plugs were implanted in artificial osteochondral defects on the trochlear groove of rat knees. After 0, 3, 6, 12, and 24 weeks of followup, samples containing the implants were mechanically evaluated by creep indentation test, chemically, and histologically by optical microscopy. The mechanical test pointed towards an increase of the implant creep modulus and the chemical analysis exhibited an increasing concentration of calcium and phosphorus within the implants over time. Optical microscopy showed no foreign body reaction and revealed formation, differentiation, and maintenance of new tissue at the defect/implant interface. The absence of implant wear indicated that the natural articular lubrication process was not disturbed by the implant. The performance of the irradiated and acetalized PVA was considered satisfactory for the proposed application.

Devices for use as an artificial articular surface in joint prostheses or in the repair of osteochondral defects.

The covering of ultra high molecular weight polyethylene (UHMWPE) and calcium hydroxyapatite (HA)/tricalcium phosphate (TCP) porous solid substrate with polyHEMA hydrogel has been studied aiming at the development of devices to be used as artificial articular surfaces in joint prosthesis or osteochondral repair grafts. Commercial porous UHMWPE was used. Ceramic porous substrate was prepared by load compaction of an HA and TCP powder mixture obtained by aqueous precipitation technique. Two different compaction loads and grain size distribution was used. Polymer particles were added to the powder mixture in order to increase the substrate porosity after the sintering process. The porous substrate was covered with polyHEMA hydrogel by in situ polymerization. Morphological analysis (SEM) showed that a hydrogel layer formed in the porous solid top surface was fixed to the substrate by mechanical interlocking because the porous surface was filled by the hydrogel. After hydrogel covering, the resultant devices showed a decrease in the compressive elastic modulus that was influenced by the porous substrate material.