Light microscopy of the lymphatics of the human atrial wall and lymphatic drainage of supraventricular pacemakers

After injection of Indian ink stained 2% gelatine in 42 human hearts the lymph drainage of the regions of supraventricular cardiac pacemakers and the patterns of the lymphatic vascular bed in the atrial wall were studied. From the sites of the pacemakers the lymph is drained into the tracheobronchial nodes in 100%. Only two of those regions are drained through additional pathways, namely the SAN region into the anterior mediastinal node situated at the azygos vein and the coronary sinus area into the anterior mediastinal lateropericardiac nodes. In the cleared specimens as microscopically the epicardial lymph vessels produce polygonal superficial network; oblique anastomoses of that network run into the deeper layers of subepicardial tissue where they join with deep irregular lymphatic network. Deep subepicardial lymph vessels are often accompanied by veins and nerves. The course of most of myocardial lymph vessels follows the position of muscle cells. In the connective septa these vessels join to form larger trunks and open into the subepicardial vessels.     

Cytokine gene expression profile in monocytic cells after a co-culture with epithelial cells

Epithelial cells represent an important source of cytokines that may modulate the influx and functions of mononuclear phagocytes. The aim of our study was to characterize changes in the gene expression of selected cytokines in human macrophages co-cultured with respiratory epithelial cells. The A549 alveolar type II-like cell line was co-cultured with THP-1 cells (monocyte/macrophage cell line) in filter-separated mode to avoid their cell-cell contact. At different time-points (0, 4, 8, 12 and 24?h), the cells were harvested separately to evaluate their gene and protein expression (IL-1 beta, IL-6, IL-8, IL-10 and GM-CSF). Quantitative RT-PCR analysis showed prominent changes in the THP-1 cytokine gene expression induced by a co-culture with A549 cells. Fourfold upregulation of mRNA expression has been found in 12 genes and 4-fold downregulation in 5 genes as compared to the unstimulated control sample with a p value smaller than 0.05. The induction of inhibin beta A and IL-1 beta mRNA after 12?h and the expression of IL-1 alpha and GM-CSF mRNA after 24?h were the most prominent. When looking at the cytokine levels in culture supernatants, IL-1 beta and IL-8 were induced early (at 8?h) as compared to the release of IL-6 and GM-CSF (at 24?h). We conclude that respiratory epithelial cells constitutively regulate the cytokine gene expression of macrophages located in their environment and might further modulate the release of cytokines by posttranslational pathways.     

The production of mannan-binding lectin is dependent upon thyroid hormones regardless of the genotype: A cohort study of 95 patients with autoimmune thyroid disorders

Complement mannan-binding lectin (MBL) deficiency is associated with increased susceptibility to infections and autoimmune diseases. Previous studies suggested that the production of MBL is stimulated by thyroid hormones. The aim of our study was to investigate this association in patients with autoimmune thyroid diseases (AITD). Serum levels of MBL and parameters of the thyroid function were determined in 62 patients with Hashimoto's thyroiditis, 33 with Graves' disease and 47 blood donors. Follow-up measurements were performed after 6 to 24 months. MBL2 genotypes were determined using multiplex PCR and compared to 359 healthy Czech individuals. Serum levels of MBL tightly correlated with thyroid hormones, leading to strongly increased MBL levels in hyperthyroidism and decreased levels in hypothyroidism. With normalization of the thyroid function during follow-up, MBL levels decreased or increased respectively. The observed correlations were not due to MBL polymorphisms since the frequency of MBL2 polymorphisms in AITD patients was not different from the general population. We conclude that AITD are not associated with MBL polymorphisms. However, the MBL production is strongly dependent on thyroid function, regardless of the genotype.     

In vitro antiplatelet activity of flavonoids from Leuzea carthamoides

Plants and their secondary metabolites, including flavonoids, exhibit a wide range of biological effects. Consequently, natural substances are receiving an increased attention in medicinal research. Owing to these facts, in vitro antiplatelet activity of ethanol summary extract and four flavonoids from Leuzea carthamoides was determined in human platelet-rich plasma. Arachidonic acid (AA), adenosine diphosphate (ADP), collagen (COL), and thrombin were used as agonists of platelet aggregation. The summary extract showed a significant inhibition of the aggregation induced by COL and ADP. Of the tested flavonoids, eriodictyol (1) and patuletin (2) influenced COL- and AA-induced aggregation. Their IC(50) values are presented. Flavonoid glycosides eriodictyol-7-beta-glucopyranoside (3) and 6-hydroxykaempferol-7-O-(6'-O-acetyl-beta-D[small cap]-glucopyranoside) (4) were found to be weak antiplatelet agents. These results confirmed the fact that glucosylation decreases the antiplatelet activity. Quantitative composition of tested flavonoids in L. carthamoides extract was also determined. Though two of the tested flavonoids inhibited platelet aggregation, further evaluation of L. carthamoides, in order to discover other antiplatelet active compounds and possible adverse health effects, is needed.     

High prevalence of anti-C1q antibodies in biopsy-proven active lupus nephritis.

BACKGROUND: Anti-C1q antibodies (anti-C1q) have been shown to correlate positively with systemic lupus erythematosus (SLE) nephritis. Several clinical studies indicated a high negative predictive value, suggesting that active lupus nephritis is rarely seen in patients with no anti-C1q. However, the true prevalence of anti-C1q at the time of active lupus nephritis has not been well established. The aim of this study was to determine prospectively the prevalence of anti-C1q in proven active lupus nephritis at the time of the renal biopsy. METHODS: In this prospective multi-centre study, we investigated adult SLE patients undergoing renal biopsy for suspected active lupus nephritis. Serum samples were taken at the time of the biopsy and analysed for the presence of anti-C1q in a standardized way. The activity of lupus nephritis was classified according to the renal histology. Biopsies were also analysed for the presence of glomerular IgG, C1q and C3 deposition. RESULTS: A total of 38 patients fulfilling at least 4/11 American College of Rheumatology (ACR) criteria for the diagnosis of SLE were included. Out of this, 36 patients had proliferative (class II, III or IV) and two had class V lupus nephritis. All but one patient with proliferative lupus nephritis were positive for anti-C1q (97.2%) compared with the 35% of control SLE patients with inactive lupus nephritis and 25% of SLE patients without lupus nephritis ever. All patients were positive for glomerular C1q (36/36) and 37/38 patients had glomerular IgG deposits. Anti-C1q strongly decreased during successful treatment. CONCLUSIONS: Anti-C1q have a very high prevalence in biopsy-proven active lupus nephritis, thus a negative test result almost excludes active nephritis. The data support the hypothesis of a pathogenic role of anti-C1q in lupus nephritis.     

Immobilization of Methyltrioxorhenium on Mesoporous Aluminosilicate Materials

The presented report focuses on an in-depth detailed characterization of immobilized methyltrioxorhenium (MTO), giving catalysts with a wide spectra of utilization. The range of mesoporous materials with different SiO₂/Al₂O₃ ratios, namely mesoporous alumina (MA), aluminosilicates type Siral (with Al content 60%–90%) and MCM-41, were used as supports for immobilization of MTO. The tested support materials (aluminous/siliceous) exhibited high surface area, well-defined regular structure and narrow pore size distribution of mesopores, and therefore represent excellent supports for the active components. Some of the supports were modified by zinc chloride in order to obtain catalysts with higher activities for instance in metathesis reactions. The immobilization of MTO was optimized using these supports and it was successful using all supports. The success of the immobilization of MTO and the properties of the prepared heterogeneous catalysts were characterized using X-ray Fluorescence (XRF), atomic absorption spectroscopy (AAS), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), physical adsorption of N₂, ultraviolet-visible spectroscopy (UV-Vis), infrared spectroscopy (FTIR), Fourier Transform Infrared Spectroscopy (FTIR) using pyridine as a probe molecule and X-ray photoelectron spectroscopy (XPS). Furthermore, the catalytic activity of the immobilized MTO on the tested supports was demonstrated on metathesis reactions of various substrates.     

Thyroid autoimmunity occurs more frequently in women with breast cancer compared to women with colorectal cancer and controls but it has no impact on relapse-free and overall survival

The aim of the study was to compare the prevalence of autoimmune thyroid diseases (AITD) in patients with breast and colorectal cancer and controls and to evaluate the impact of AITD on the outcome of patients with breast cancer. Serum levels of TSH (thyroid-stimulating hormone), FT4 (free thyroxine), TPOAb (antibodies to thyroid peroxidase), TgAb (antibodies to thyroglobulin), selenium and prolactin were investigated in 210 randomly chosen women (89 with breast cancer and 72 with colorectal cancer after breast or abdominal surgery and 49 controls without oncological diseases). Eighty-four women with breast cancer were followed for a median of 136.0 months. The prevalence of positive titres of TPOAb (>60 kIU.l(-1)) was higher in the women with breast cancer as compared to positive titres in women with colorectal cancer and the controls (29.8 vs. 12.5 and 12.2%, respectively, P=0.016 and 0.036, respectively). Similarly, the prevalence of clinical, ultrasound and laboratory documented AITD was higher in women with breast cancer as compared to that in women with colorectal cancer and the controls (35.7 vs. 18.1 and 16.3%, respectively, P=0.014 and 0.029, respectively). We did not find any prognostic significance of FT4, TSH, TgAb, TPOAb, prolactin and the presence of AITD on relapse-free and overall survival among women with breast cancer. A negative prognostic significance of body mass index and serum levels of selenium on relapse-free survival was found. In conclusion, the prevalence of euthyroid AITD was higher in women with breast cancer as compared to euthyroid AITD in women with colorectal cancer and controls. The presence of AITD did not have an impact on the outcome of women with breast cancer.     

Monoclonal antibodies generated in carbonic anhydrase IX-deficient mice recognize different domains of tumour-associated hypoxia-induced carbonic anhydrase IX

Transmembrane carbonic anhydrase IX (CA IX) is frequently expressed in human tumours in response to hypoxia and may serve as a tumour marker and therapeutic target. So far, only a single monoclonal antibody (MAb) M75 with an epitope in the N-terminal proteoglycan (PG)-like region has been available for detection purposes. Attempts to produce MAbs against other parts of CA IX were unsuccessful due to the immunodominance of the PG region that significantly differs between human and mouse homologues. To overcome this problem, we used various forms of human CA IX antigen to immunize CA IX-deficient mice recently produced by targeted disruption of Car9 gene. Here, we describe new MAbs that react with human, but not mouse CA IX in different immunodetection settings, and show no cross-reactivity with CA I, II and XII. MAb IV/18 is directed to the PG region, while the other six antibodies bind to the CA domain, as determined by CA IX deletion variants. IV/18 recognizes a linear epitope, while anti-CA MAbs V/10, V/12, VII/20, VII/28, VII/32 and VII/38 react with conformational epitopes clustered into three antigenic sites. The new antibodies represent important tools for improving our knowledge of structure-function relationships in the CA IX molecule and a better understanding of the role of CA IX in cancer development. Moreover, the availability of the MAbs specific for distinct antigenic regions on two separate extracellular domains offers an opportunity to elaborate a sensitive assay that could be particularly important for CA IX detection in body fluids of cancer patients.