Experimental autoimmune myocarditis in rats and therapeutic histamine H1 - H4 receptor inhibition

Myocarditis, a life threatening disease, is still not adequately treated. Histamine plays an important role in physiology and pathophysiology of cardiovascular system. All four histamine receptors (H₁R - H₄R), are present in the heart. Experimental autoimmune myocarditis (EAM) was used to investigate which histamine receptor had a greater impact on the disease's progression. EAM was evoked in Lewis rats by porcine myosin immunization. Mepyramine, ranitidine and ciproxifan were used to inhibit H₁R, H₂R and H₃R receptors, respectively, and 2,4-diaminopyrimidines: ST994, ST1012, ST1006 were ligands of H₄R. Quinapril, an ACE inhibitor, served as a reference drug. Drugs were administered daily, either from 0 - 2 weeks or from 2 to 4 weeks post EAM induction. Cardiac dysfunction developed with significant decreases in left ventricular ejection fraction and fractional shortening due to dilatation and wall thickening. EAM rats treated with mepyramine and ST994 in weeks 0 - 2 had the lowest decreases. These treated with ST994, ST1012 or quinapril performed much better the following 2 weeks without therapy than did the other groups. On autopsy their hearts were smaller, less fibrotic, histopathological changes in them of a lower grade. When the treatment started with 2 weeks' delay, the ST994-treated EAM rats showed the highest median survival. H₄ receptor antagonism inhibits heart remodelling, preserves heart contractility, improves survival and may be of potent therapeutic relevance in human clinics. The blockade of H₁ receptor inhibits heart dilatation but does not prolong the life.

The Impact of Three Genospecies of Borrelia on Expression of Genes Associated with Chemokines and Their Receptors in Normal Human Dermal Fibroblasts in Vitro

An important role in pathomechanism of Lyme disease is played by the ability of spirochetes to spread within tissues, and to adhere (to platelets, erythrocytes and vascular epithelium). The principal factors regulating that process are chemokines, cytokines and adhesion particles. The aim of this study was to select genes related to the chemokines and their receptors, differentiating the type of infection in the system model, i.e. a culture of normal human diploid fibroblasts infected with three different spirochete genospecies: B. afzelii, B. garinii and B. burgdorferii sensu stricto, by comparing the infected fibroblast culture with that of the control fibroblast. The differences in the expression of genes selected on the basis of a scientific database Affymetrix were analysed by comparing transcriptomes from the four cultures of fibroblasts, using the oligonucleotide microarrays HG_U133A. In the result of infection of fibroblast cultivation with a specific Borrelia genospecies, a variable expression of the chemokines and their receptors, specific for one genospecies was observed. The fibroblast infected with B. afzelii expressed CCL4, CCL1, CCL2 and CCR10; with B. garinii - CXCL12, IL6, CCR3 and CXCR5; and with B. burgorferii sensu stricto - CCL5, CCR1, CCL3, CCL16, CXCR6, IL8, CXCR7 and CXCR3.

Differential expression of tripartite motif-containing family in normal human dermal fibroblasts in response to porcine endogenous retrovirus infection

Antiretroviral restriction factors may play an essential role in the safety of xenotransplantation. Therefore, the present study focused on investigation of the changes in the tripartite motif-containing family (TRIM) gene expression in normal human dermal fibroblasts with and without lipopolysaccharide stimulation in response to porcine endogenous retrovirus infection. Analysis of the expression profile of TRIMs was performed using oligonucleotide microarrays and QRT-PCR. Nine (TRIM1, TRIM2, TRIM5, TRIM14, TRIM16, TRIM18, TRIM22, TRIM27 and TRIM31) statistically significantly differentially expressed genes were found (P < 0.05, one-way ANOVA). In conclusion, comprehensive analysis of retroviral restriction factor gene expression in human dermal fibroblasts before and after porcine endogenous retrovirus infection with and without LPS stimulation may suggest association of the selected TRIMs with antiretroviral activity.

BCL2 and BAX mRNA concentration profile in fibrillary astrocytoma

A high level of the BCL2 protein and the lack of apoptosis promoting protein BAX are beginning to be treated as markers of cellular resistance to anti-neoplastic drugs. The object of the study were specimens from stereotactic biopsy of Astrocytoma fibrillare in the central brain area, inaccessible to conventional surgery. The cytological preparations have been evaluated with histopathological and immunohistochemical methods in order to determine the origin of the tumour and assess cell proliferation activity. The molecular analysis conducted in order to determine the sensitivity of the tumour to radio- or chemotherapy included the determination of the number of mRNA BCL2 alpha and beta molecules and of BAX in 1 microg total RNA obtained from microscope slides. A higher expression of BAX than of BCL2-alpha is a prognosis for a positive result of chemo- or radiotherapy. A trace number of mRNA BCL2-beta molecules and a smaller number of mRNA BCL2-alpha molecules than mRNA BAX is a good prognosis for therapy.

Dynamics of HCV replication in patients with chronic hepatitis C during interferon and ribavirin combined therapy

Objective of the present study was to determine the effect of combined therapy with interferon alfa-2b (3 MU; thrice weekly s.c.) and ribavirin (1200 mg daily p.o.) on the number of copies of positive and negative strands of the hepatitis C virus RNA (HCV RNA) in patients with biopsy-proven chronic hepatitis C. Number of copies of both strands was determined by a TaqMan reverse transcription quantitative polymerase chain reaction (TaqMan RT Q-PCR) in the whole blood before treatment, and 4, 12 or 24 weeks after introduction of the treatment. Before the treatment positive strand of HCV RNA was more frequently detectable and its level was higher compared to that of the negative strand. In several patients, we observed therapy-induced transient appearance or increase in the number of copies of the negative HCV RNA strand. As a result of 24-week treatment, the negative strand of HCV RNA was eliminated from the blood more effectively than the positive strand. Our results suggest that the assessment of dynamics of changes of the positive and negative strands levels of HCV RNA in interferon-naive patients with chronic hepatitis C may be useful in monitoring short-term effectiveness of combined antiviral therapy. They also indicate that TaqMan RT Q-PCR appears to be a valuable tool in monitoring the therapy in these patients.

[Prenatal diagnostics of Toxoplasma gondii invasion by quantitative method of PCR-TaqMann]

Routine serological diagnosis of toxoplasmosis provides high sensitivity, but not high specificity. The high sensivity combined with high specifity offered by PCR-TaqMann as well as the degree of infection led us to investigate the presence and levels of T. gondii DNA in amniotic fluid, maternal and neonatal blood in cases of pregnancy where infection with this agent was suspected. Samples of amniotic fluid and blood were taken from pregnant women. Postnatal blood samples were also taken from their infants. Presence and levels of toxoplasma DNA was investigated using PCR-TaqMann. PCR products were detected by electrophoresis on polyacrylamide gel. The PCR-TaqMann test is highly sensitive, specific and useful method allowing detection of the parasite genome and assessement of its level.

[Detection of Toxoplasma gondii DNA by PCR in mother's blood, amniotic fluid and child's blood in selected cases of pathological pregnancy]

Prenatal screening of Toxoplasma gondii infection is controversial. The diagnosis is based on serological tests detecting IgM and IgG antibodies against T. gondii, but interpretation of these tests results is often confusing. It is commonly made retrospectively when serological screening indicates a possibility of recent infection. Most women have antibodies against T. gondii and serial testing is required only in monitoring of pregnancies where initial screening is negative. The introduction of Polymerase Chain Reaction (PCR) assay for detection of Toxoplasma gondii DNA in selected cases of pathologic pregnancies has permitted a more accurate and faster diagnosis of congenital toxoplasmosis infections.

[Usefulness of quantitative assessment of Toxoplasma gondii genome using PCR-TaqMan in amniotic fluid, maternal and neonatal blood in selected complications in pregnancy]

Routine serological diagnosis of Toxoplasmosis provides high sensitivity, but not high specificity. The high sensitivity combined with high specificity offered by PCR-TaqMan as well as the degree of infection led us to investigate the presence and levels of Toxoplasma gondii genome in amniotic fluid, maternal and neonatal blood in cases of pregnancy where infection with this agent was suspected.

MATERIALS AND METHODS

Samples of amniotic fluid and blood were taken from 28 women between the 16th and 40th week of gestational age. Postnatal blood samples were also taken from their infants. Included in the study group were women with IUGR, PROM, preterm delivery imminent, Toxoplasmosis in previous pregnancies, raised IgG or IgM anti-Toxoplasma antibody titers and with amniotic fluid disturbances (oligohydramnios and polyhydramnios). Presence and levels of Toxoplasma genome was investigated using PCR-TaqMan. PCR products were detected by electrophoresis on polyacrylamide gel.

RESULTS

Toxoplasma gondii genome was detected in blood from 13 women, 3 newborns and in amniotic fluid from one other women. Toxoplasma genome was detected in blood from one newborn, but was not detected in sample from its mother.

CONCLUSIONS

The PCR-TaqMan test is highly sensitive and specific method allowing detection of the parasite genome and assessment of its level. Limitations of this method are its relatively high cost and poor access to ABI PRISM 7700 (TaqMan) sequence detector. The PCR TaqMan is useful in cases, where serological tests for the presence of infections are ambiguous.