Microarray analysis of relative gene expression stability for selection of internal reference genes in the rhesus macaque brain

Background  

Normalization of gene expression data refers to the comparison of expression values using reference standards that are consistent across all conditions of an experiment. In PCR studies, genes designated as "housekeeping genes" have been used as internal reference genes under the assumption that their expression is stable and independent of experimental conditions. However, verification of this assumption is rarely performed. Here we assess the use of gene microarray analysis to facilitate selection of internal reference sequences with higher expression stability across experimental conditions than can be expected using traditional selection methods.     

Biological and Molecular Characterization of Polish Isolates of Tomato torrado virus*

Three isolates of Tomato torrado virus (ToTV) were found in Poland. The isolates were characterized on the basis of their symptomatology on plant species, serological reactions, electron microscopy, and nucleotide and amino acid sequence analyses of coat protein subunit genes. In comparative tests, the Polish ToTV isolates were shown to be closely related to each other and also to the isolate from Spain.     

Chondrocyte suspension in fibrin glue

Autologous chondrocyte implantation has been shown to be a promising method for treatment of deep articular cartilage defects. The hyaline cartilage formed by implanted autologous chondrocytes has biomechanical properties similar to those of natural articular cartilage. Between June 2006 and September 2008 we performed Autologous chondrocyte implantation (ACI) in 50 patients and the chondrocytes were supported in fibrin glue. The cartilage biopsy samples were taken from the non-weight bearing area of the patient’s femoral condyle and the samples were transferred to the cell culture laboratory. Chondrocyte were kept in culture about 20 days. Fibrin glue was used as a three dimensional carrier for chondrocyte implantation. A 450 ml of patient’s own blood was collected prior to transplantation to produce autologous fibrinogen. Alternatively the allogenic fibrinogen was prepared from Regional Blood Center voluntary donors. Before surgery the chondrocyte suspension was mixed with fibrin glue and gel—like fibrograft was prepared. The total number of cells and the size of fibrograft depended on the defect size in the knee. Our results suggest that ACI technique with fibrin glue is a promising method for treatment of cartilage defect.     

Inhibitory effect of thalidomide on the growth, secretory function and angiogenesis of estrogen-induced prolactinoma in Fischer 344 rats

The process of angiogenesis has been found to be essential for the development of estrogen-induced pituitary prolactinoma in Fischer 344 rats. Thalidomide [(alpha-(N-phthalimido)-glutarimide] is known to be a potent immunomodulatory drug with antiangiogenic properties, but its effect on lactotroph cell secretory function and pituitary prolactinoma formation has not been described yet. The purpose of this study was to examine the effects of thalidomide on secretion of prolactin (PRL) and vascular endothelial growth factor (VEGF), cell proliferation, apoptosis and angiogenesis within the anterior pituitary gland in long-term diethylstilboestrol (DES)-treated male F344 rats in vivo and in vitro. It was found that DES sharply increased serum PRL and VEGF levels. On the other hand, simultaneous treatment of F344 rats with thalidomide for the last 15 days of the experiment attenuated the stimulatory effect of DES on PRL and VEGF secretion. It also diminished prolactin cell proliferation evaluated as the number of proliferating cell nuclear antigen (PCNA)-positive stained cell nuclei and increased the number of apoptotic bodies determined by the terminal deoxynucleotidyl-mediated dUTP nick-end labeling (TUNEL) method in sections of the DES-induced pituitary prolactinoma. The density of pituitary microvessels evaluated by microscopic counting of CD-31-positive blood vessels was also diminished by the tested drug. In addition, thalidomide (10(-4) to 10(-6) M) inhibited cell proliferation, prolactin and VEGF secretion from rat pituitary prolactinoma cells cultured in vitro. In conclusion, our results provide strong evidence for the antiprolactin and antitumor activity of thalidomide in experimentally DES-induced pituitary adenoma.     

Human papillomavirus type 16 E7 peptide-directed CD8+ T cells from patients with cervical cancer are cross-reactive with the coronavirus NS2 protein

Human papillomavirus type 16 (HPV16) E6 and E7 oncoproteins are required for cellular transformation and represent candidate targets for HPV-specific and major histocompatibility complex class I-restricted CD8(+)-T-cell responses in patients with cervical cancer. Recent evidence suggests that cross-reactivity represents the inherent nature of the T-cell repertoire. We identified HLA-A2 binding HPV16 E7 variant peptides from human, bacterial, or viral origin which are able to drive CD8(+)-T-cell responses directed against wild-type HPV16 E7 amino acid 11 to 19/20 (E7(11-19/20)) epitope YMLDLQPET(T) in vitro. CD8(+) T cells reacting to the HLA-A2-presented peptide from HPV16 E7(11-19(20)) recognized also the HLA-A2 binding peptide TMLDIQPED (amino acids 52 to 60) from the human coronavirus OC43 NS2 gene product. Establishment of coronavirus NS2-specific, HLA-A2-restricted CD8(+)-T-cell clones and ex vivo analysis of HPV16 E7 specific T cells obtained by HLA-A2 tetramer-guided sorting from PBL or tumor-infiltrating lymphocytes obtained from patients with cervical cancer showed that cross-reactivity with HPV16 E7(11-19(20)) and coronavirus NS2(52-60) represents a common feature of this antiviral immune response defined by cytokine production. Zero of 10 patients with carcinoma in situ neoplasia and 3 of 18 patients with cervical cancer showed > or =0.1% HPV16 E7-reactive T cells in CD8(+) peripheral blood lymphocytes. In vivo priming with HPV16 was confirmed in patients with cervical cancer or preinvasive HPV16-positive lesions using HLA-A2 tetramer complexes loaded with the E6-derived epitope KLPQLCTEL. In contrast, we could not detect E6-reactive T cells in healthy individuals. These data imply that the measurement of the HPV16 E7(11-19(20)) CD8(+)-T-cell response may reflect cross-reactivity with a common pathogen and that variant peptides may be employed to drive an effective cellular immune response against HPV.     

The effect of melanins on oxidation of lecithin in liposomal membranes

Lecithin peroxidation in liposomal membranes induced by UV light was studied in the presence of natural eye melanin and synthetic melanins prepared from various precursors. It was shown that melanins inhibited lecithin photooxidation, and that the extent of this effect strongly depended on the type and concentration of melanin. Comparative study indicated that melanin obtained from adrenolutin was the most effective antioxidant. The ability to inhibit lipid peroxidation depends both on the concentration of paramagnetic centers in the melanin polymer and the accessibility of these centers for free radicals formed during irradiation of liposomes.     

Frequency of lactase persistence genotype in a healthy Polish population

The majority of mammals are unable to digest lactose due to post-weaning deactivation of the LCT gene, which is responsible for encoding the enzyme lactase (i.e., adult-type hypolactasia). A substitution of C with T at position −13910 bp upstream of the LCT gene has been linked to the lactase persistence phenotype in European populations. We investigated the frequency of LCT-13910C>T polymorphism in 223 blood donors from central Poland. All samples were genotyped by polymerase chain reaction and direct sequencing. The LCT-13910 T allele (lactase persistence) was present in 51% of individuals sampled from the Polish population. We did not find any non-European variants associated with lactase persistence (LCT-13907C>G, LCT-13913T>C, LCT-13915T>G), or any new polymorphisms within the sequenced region. Allele frequencies obtained are in agreement with results from other countries and confirm the unique pattern of distribution of the LCT-13910C>T genotype in Europe.