Strategies to manage hepatitis C virus (HCV) infection disease burden - volume 2

The hepatitis C virus (HCV) epidemic was forecasted through 2030 for 15 countries, and the relative impact of two scenarios was considered: (i) increased treatment efficacy while holding the treated population constant and (ii) increased treatment efficacy and increased annual treated population. Increasing levels of diagnosis and treatment, in combination with improved treatment efficacy, were critical for achieving substantial reductions in disease burden. In most countries, the annual treated population had to increase several fold to achieve the largest reductions in HCV-related morbidity and mortality. This suggests that increased capacity for screening and treatment will be critical in many countries. Birth cohort screening is a helpful tool for maximizing resources. In most of the studied countries, the majority of patients were born between 1945 and 1985.

The present and future disease burden of hepatitis C virus (HCV) infections with today's treatment paradigm - volume 2

Morbidity and mortality attributable to chronic hepatitis C virus (HCV) infection are increasing in many countries as the infected population ages. Models were developed for 15 countries to quantify and characterize the viremic population, as well as estimate the number of new infections and HCV related deaths from 2013 to 2030. Expert consensus was used to determine current treatment levels and outcomes in each country. In most countries, viremic prevalence has already peaked. In every country studied, prevalence begins to decline before 2030, when current treatment levels were held constant. In contrast, cases of advanced liver disease and liver related deaths will continue to increase through 2030 in most countries. The current treatment paradigm is inadequate if large reductions in HCV related morbidity and mortality are to be achieved.

Historical epidemiology of hepatitis C virus (HCV) in select countries - volume 2

Chronic hepatitis C virus (HCV) infection is a leading cause of liver related morbidity and mortality. In many countries, there is a lack of comprehensive epidemiological data that are crucial in implementing disease control measures as new treatment options become available. Published literature, unpublished data and expert consensus were used to determine key parameters, including prevalence, viremia, genotype and the number of patients diagnosed and treated. In this study of 15 countries, viremic prevalence ranged from 0.13% in the Netherlands to 2.91% in Russia. The largest viremic populations were in India (8 666 000 cases) and Russia (4 162 000 cases). In most countries, males had a higher rate of infections, likely due to higher rates of injection drug use (IDU). Estimates characterizing the infected population are critical to focus screening and treatment efforts as new therapeutic options become available.

Paradoxical effects of two oximes on nitric oxide production by purified NO synthases, in cell culture and in animals

We have studied the impact of two novel compounds TO-85 (2,6-di-(alpha-aziridino-alpha-hydroxyiminomethyl)pyridine and TO-133 (bis-(diaziridinoglyoximato)copper), designed as NO donors, on nitrite production by cell cultures, NO production in rat tissues and their ability to inhibit purified NO synthases (NOS). Both substances induced considerable increase of nitrite production in cell cultures. When NO production was assayed in rat organs by means of ESR using Fe(DETC) as a spin trap the anticipated NO-increasing activity of TO-85 was observed only in kidneys; the NO level increasing almost 10-fold. Treatment of rats with TO-133, decreased the NO concentration in brain cortex, cerebellum and liver. When the drugs were administered to animals with high level of iNOS expression induced by LPS, TO-85 did not significantly modify the LPS-induced NO production; administration of TO-133 caused a significant decrease of NO production in blood, brain cortex and cerebellum. Only high concentrations of TO-85 were capable of inhibiting iNOS (IC50=7 mM), the substance inhibited eNOS at lower concentrations (IC50=250 microM). Inhibitory activities of TO-85 on nNOS were dependent on BH4 concentrations, suggesting eventual competition of TO-85 with BH4 when the substance interacts with nNOS. TO-133 reduced eNOS activity with IC50=200 microM, nNOS activity with IC50=200 microM, iNOS activity was not much affected by this substance. Thus, the two tested compounds manifest opposite effects on NO production by purified enzymes and in cell culture. The pattern of the NO synthesis modification in a living animal appears to be even more complex. Our results stress the importance of direct measurements of NO in the tissues using the ESR method.

Synthesis and antitumour activity of trimethylsilylpropyl substituted benzimidazoles

The quaternisation of N-substituted benzimidazoles by heating with various alkyl, allyl, propargyl and benzyl chlorides and bromides leads to the formation of benzimidazolinium salts. The interaction of N-monosubstituted benzimidazoles with various salts (CuCl2, ZnCl2, CoCl2, PdCl2 and AgNO3) yielded stable solid complexes. Potential cytotoxic activity of synthesised benzimidazolinium salts and benzimidazole metal complexes was tested in vitro on four monolayer tumour cell lines: MG-22A (mouse hepatoma), HT-1080 (human fibrosarcoma), B16 (mouse melanoma), Neuro 2A (mouse neuroblastoma) and normal mouse fibroblast cells. A preliminary analysis of the structure-activity relationship for the benzimidazole derivatives clearly indicates that the character of substituents in the benzimidazole ring has strong influence on the cytotoxic activity. The insertion of the silicon atom into the N-alkyl chain increases the cytotoxic activity of benzimidazolinium salts significantly, which show a very significant potency in vitro against all studied tumour cell lines, being particularly active in experiments with B16 (mouse melanoma). TD50 for the most active compounds are in the range 0.001-0.008 microg x ml(-1). Cytotoxicity of benzimidazole metal complexes (L2MX2) strongly depends on the metal nature. 1-(3-trimethylsilylpropyl)benzimidazole in dose 1 mg x kg(-1) inhibits carcinoma S-180 tumour growth by 62% (on ICR mice).

Synthesis and antitumor activity of selected 7-alkylidene substituted cephems

Selected 7-alkylidene substituted cephems were synthesized and subjected to antitumor assay. The effect of substituents was examined to establish structure-activity relationships. It was found that the intensive intracellular generation of nitric oxide induced by tert-butyl 7-alkylidene cephalosporanate sulfones could be also regarded as an additional cytotoxic factor taking place both in vitro and in vivo experiments.

Use of a gel-forming dipeptide derivative as a carrier for antigen presentation

A dipeptide of the formula Fmoc-Leu-Asp and some other related dipeptides were synthesized in solution by standard methods. When such peptides are dissolved in water at concentrations below 1% at 100 degrees C and cooled below 60 degrees C they form turbid solutions and eventually viscoelastic gels at lower temperatures. Such gels are thermoreversible and can also be disrupted by mechanical agitation. At a concentration of 2 mg/ml the peptide Fmoc-Leu-Asp forms an aqueous gel at 60 degrees C with a shear modulus of 80 Pa measured at a frequency of 1 rad/s. Peptide solutions undergo an abrupt increase in light scattering between 1 and 1.5 mg/ml at both 23 and 60 degrees C. By analogy with previous observations of other systems, this increase appears to be due to the formation of filamentous micelles and the aggregation of filaments into a three-dimensional network. When low molecular weight adamantanamine derivatives, which are inherently non-antigenic antiviral drugs, were incorporated into the Fmoc-Leu-Asp gel and injected into rabbits, high titre specific antibodies were efficiently produced without the need for additional adjuvant. Both the physical properties of the gel and its effect on the antigenicity of low molecular weight compounds suggest a number of practical applications.