Hepatitis C--treatment of untreated (naive) patients

The most important therapeutic advance in recent years considering chronic HCV infection has occurred with the introduction of pegylated interferon (PEG IFN) in the combination therapy with ribavirin, which results in better sustained virologic response (SVR). Although an SVR is difficult to correlate with improved survival because of the necessity for long-term follow up, the absence of detectable serum HCV RNA has been associated with resolution of liver injury, reduction in hepatic fibrosis, and a low likelihood of a relapse of the HCV infection. Two large pivotal trials examined the efficacy of PEG IFN plus ribavirin in the treatment of chronic HCV infection. Overall, PEG IFN plus ribavirin was more effective than the standard interferon-ribavirin combination. SVR rates were similar with both forms of PEG IFN (PEG IFN alfa-2a and PEG IFN alfa-2b) when used in combination with ribavirin. SVR rates of 42% and 46% were achieved in patients with genotype 1 compared to rates of 76% and 82% in patients with genotypes 2 and 3. Factors associated with successful therapy included genotypes other than 1, lower baseline viral levels, less fibrosis or inflammation on liver biopsy, and lower body weight or body surface area. Twenty four weeks of treatment with a combination of PEG IFN and ribavirin appears to be sufficient for patients infected with genotypes 2 and 3, while patients with genotype 1 need 48 weeks of treatment. Early virologic response (EVR), defined as undetectable HCV RNA or a minimum 2 log decrease in viral load (relative to baseline) after the first 12 weeks of treatment, is predictive of SVR and should be a routine part of monitoring patients with genotype 1. Patients who fail to achieve an EVR have only a small chance of achieving an SVR, therefore treatment should be discontinued after 12 weeks. It is also recommended to treat patients with acute hepatitis C to reduce the risk of developing chronic infection. Treatment should start 12 weeks after the onset of symptoms and includes 24 weeks of monotherapy with PEG IFN.     

Novel pyrazinone and pyridinone thrombin inhibitors incorporating weakly basic heterobicyclic P(1)-arginine mimetics

The design, synthesis and biological activity of new thrombin inhibitors with a pyridinone or pyrazinone core and different heterobicyclic P(1) arginine side-chain mimetics are described. The arginine side-chain mimetics used in this study are (+/-)-4,5,6,7-tetrahydro-2H-indazol-5-ylmethanamine and both enantiomers thereof, (+/-)-4,5,6,7-tetrahydro-1,3-benzothiazole-2,6-diamine and the corresponding R enantiomer. Compound 25, the most potent in the series of pyrazinone inhibitors, exhibited a K(i) of 41 nM in vitro and high selectivity against trypsin and factor Xa.     

POLARIZATION FLUORESCENCE STUDIES ON PROTEOLYTIC ACTIVITY OF α2-MACROGLOBULIN-TRYPSIN COMPLEXES

When digestive enzymes are released into the blood, they may be completely inactivated by a variety of inhibitors present (alpha-1-protease inhibitor, antithrombin III, α₂-plasmin inhibitor, etc.) or only partially neutralized by α₂-macroglobulin. In this study, polarization fluorescence is used to demonstrate that complexes of α₂-macroglobulin with trypsin can digest β-endorphin, adrenocorticotropin, and β-lipotropin. Furthermore, it has been shown that a small trypsin inhibitor (trasylol, mol. wt. 6500) can prevent this digestion, but that larger inhibitory proteins (i.e. soybean trypsin inhibitor, mol. wt. 21 500; α₁-protease inhibitor, mol. wt. 50000) cannot.     

Childhood abuse and white matter integrity in bipolar disorder patients and healthy controls

Childhood trauma has a negative impact on the developing brain and increases the risk for almost all psychiatric disorders including bipolar disorder. White matter abnormalities may play a role in the persistently increased risk for bipolar disorder following childhood trauma.We therefore examined the influence of childhood abuse and neglect on white matter integrity using diffusion tensor imaging (DTI), quantified as fractional anisotropy (FA), in patients with bipolar I disorder (N = 251) and healthy controls (N = 163). Bipolar patients experienced more childhood abuse (30.6% vs 8.0%; p< 0.001) and childhood neglect (36.3% vs 22.7%; p = 0.003) than controls. Childhood abuse had different effects on whole brain FA in patients with bipolar disorder compared to healthy individuals (F[1,410] = 3.060; p = 0.006). Specifically, whereas patients with bipolar disorder with childhood abuse had lower FA in widespread regions of the brain relative to patients without childhood abuse (t[249] = 2.28; p = 0.024), no differences were found between healthy individuals with and without abuse (t[161]=?0.18; p = 0.986). Differences in mean FA significantly mediated the association between childhood abuse and bipolar disorder. In contrast, childhood neglect was not significantly associated with FA in patients with bipolar disorder nor in healthy controls.Together, these results show that childhood abuse but not neglect is associated with lower integrity of white matter microstructure across the brain in patients with bipolar I disorder but not in healthy individuals. Therefore, white matter integrity might be involved the relationship between childhood abuse and bipolar disorder, even though the directionality cannot be proven due to the cross-sectional design of our study.     

Overcoming challenges of HERG potassium channel liability through rational design: Eag1 inhibitors for cancer treatment

Two decades of research have proven the relevance of ion channel expression for tumor progression in virtually every indication, and it has become clear that inhibition of specific ion channels will eventually become part of the oncology therapeutic arsenal. However, ion channels play relevant roles in all aspects of physiology, and specificity for the tumor tissue remains a challenge to avoid undesired effects. Eag1 (K_V10.1) is a voltage-gated potassium channel whose expression is very restricted in healthy tissues outside of the brain, while it is overexpressed in 70% of human tumors. Inhibition of Eag1 reduces tumor growth, but the search for potent inhibitors for tumor therapy suffers from the structural similarities with the cardiac HERG channel, a major off-target. Existing inhibitors show low specificity between the two channels, and screenings for Eag1 binders are prone to enrichment in compounds that also bind HERG. Rational drug design requires knowledge of the structure of the target and the understanding of structure–function relationships. Recent studies have shown subtle structural differences between Eag1 and HERG channels with profound functional impact. Thus, although both targets' structure is likely too similar to identify leads that exclusively bind to one of the channels, the structural information combined with the new knowledge of the functional relevance of particular residues or areas suggests the possibility of selective targeting of Eag1 in cancer therapies. Further development of selective Eag1 inhibitors can lead to first-in-class compounds for the treatment of different cancers.     

The Impact of Patient’s Socio-Demographic Characterictics,Comorbidities and Attitudes on Flu Vaccination Uptake in Family Practice Settings

Objectives

In Slovenia, the role of family physicians in primary care and preventive procedures is very important. Influenza vaccination rates in Slovenia are low. The reasons for low vaccination rates in Slovenia were not clear. We suppose that patient’s beliefs and attitudes are important factors. We assessed patients’ opinions regarding the acceptance of flu vaccination by their family physicians and their beliefs and attitudes about flu and vaccination. The aim was to check out factors that influence the decision to take the vaccine in family physician offices.

Methods

This was a cross-sectional, multicenter, observational study in the Styria region in Slovenia. We included patients from seven family physicians during regular office visits. They filled in a questionnaire about their general demographic data and attitudes regarding influenza and vaccination. The main outcome was the decision to be vaccinated.

Results

The logistic regression model identified five predictors for influenza vaccination, namely: heart disease, previous vaccination, an agreement with the beliefs ‘the vaccination is an efficient measure to prevent influenza’, ‘after the vaccination there are usually no important side effects’ and ‘the vaccination is also recommended for a healthy adult person’. The belief that vaccinations harm the immune system is negatively associated with vaccination.

Conclusions

Patients’ beliefs are an important factor to decide for vaccination or not. Family physician teams should discuss with patients their beliefs and concerns about vaccination.     

Matrix metalloproteinases and E-cadherin immunoreactivity in different basal cell carcinoma histological types

The immunohistochemical staining of matrix metalloproteinases (MMPs) and E-cadherin in tumor epithelial and stromal cells was analyzed in a group of solid, superficial spreading and cystic tumors and in a group of morpheaform and recurrent basal cell carcinomas (BCC) in order to determine whether any of these factors possibly contribute to tumor therapy resistance. Tumor tissues of 64 patients were obtained by complete excisional or curettage biopsy of BCC and these were immunohistochemically stained for MMP-1, MMP-2, MMP-9, MMP-13 and E-cadherin. In the morpheaform and recurrent BCC, MMP-9 expression significantly increased in the stroma, while E-cadherin expression was negative in epithelial cells. Odds ratio for development of morpheaform and recurrent BCC was 6.2 for positive MMP-1 immunostaining in epithelial tumor cells, 5.8 for positive MMP-9 immunostaining in tumor stroma, 3.2 for positive MMP-13 immunostaining in tumor stroma, and 4.5 for negative E-cadherin in epithelial tumor cells. Our results suggest that MMP-1 immunostaining in tumor cells, MMP-9 expression in stromal cells, and absence of E-cadherin expression are associated with morpheaform and recurrent BCC.     

MurD enzymes from different bacteria: evaluation of inhibitors

D-Glutamic acid-adding enzyme (MurD ligase) catalyses the addition of D-glutamic acid to UDP-N-acetylmuramoyl-L-alanine, an essential cytoplasmic step in the pathway for bacterial cell-wall peptidoglycan synthesis. As such, it represents an important antibacterial drug-discovery target enzyme. Recently, several series of compounds have been synthesised and found to inhibit MurD from Escherichia coli, the best one having an IC(50) value of 8 μM. In the present work, we have tested 20 of these compounds against the MurD enzymes from Staphylococcus aureus, Streptococcus pneumoniae, Borrelia burgdorferi and Mycobacterium tuberculosis. Most of the E. coli MurD inhibitors appeared less efficient against the four other orthologues. This divergent result can be explained by the differences in amino acid sequences and topologies of the active sites of the MurD ligases studied.     

Ethanol and acetaldehyde disturb TNF-alpha and IL-6 production in cultured astrocytes

Ethanol disturbs astroglial growth and differentiation and causes functional alterations. Furthermore, many signalling molecules produced by astrocytes contribute to these processes. The aim of the present study was to investigate the influence of ethanol and its primary metabolite, acetaldehyde, on TNF-alpha and IL-6 production in a rat cortical astrocyte primary culture. We are the first to report that both ethanol and acetaldehyde can modulate TNF-alpha and IL-6 secretion from cultured astrocytes. Long-term exposure (7 days) to ethanol and acetaldehyde was more toxic than an acute (24 hours) exposure. However, both compounds showed a biphasic, hormestic effect on the IL-6 secretion after the acute as well as the long-term exposure, and the maximum stimulation was reached for 50-mM ethanol and 1-mM acetaldehyde after 7-day exposure. In contrast, both compounds reduced the TNF-alpha secretion, where the effect was concentration-dependent. The catalase inhibitor 2-amino-1,2,4 triazole significantly reduced the ethanol toxicity in the cultured astrocytes after the acute as well as the long-term exposure. In conclusion, both ethanol and acetaldehyde affect the production of IL-6 and TNF-alpha in cultured astrocytes. The effect depends on the concentration of the compounds and the duration of the exposure. Acetaldehyde is a more potent toxin than ethanol, and ethanol's toxicity in the brain is at least partially due to its primary metabolite, acetaldehyde.