Interactions of Platinum and Ruthenium Coordination Complexes with Pancreatic Phospholipase A2 and Phospholipids Investigated by MALDI TOF Mass Spectrometry

Phospholipase A₂ is involved in propagation of inflammatory processes and carcinogenesis through its role in phospholipid metabolism, and release of arachidonic acid and lysophospholipids. Recent findings on correlation between elevated PLA₂ activity and metastatic cancer render this enzyme an attractive target for cancer therapy. On the other hand, due to a broad range of oxidation states under physiological conditions and a high affinity for protein binding, platinum and ruthenium coordination complexes are promising candidates for PLA₂ inhibitors. In this article, we discuss the interactions of Pt and Ru coordination complexes with PLA₂ and phospholipids, as well as the application of MALDI‐TOF mass spectrometry for screening PLA₂ inhibitors. Owing to the ability of this technique to simultaneously detect and monitor changes in substrate and product concentrations, the inhibitor mechanisms of both Pt and Ru complexes with various ligands were determined.     

Cholesterol Sulfate and Cholesterol Sulfotransferase Inhibit Gluconeogenesis by Targeting Hepatocyte Nuclear Factor 4α

Sulfotransferase (SULT)-mediated sulfation represents a critical mechanism in regulating the chemical and functional homeostasis of endogenous and exogenous molecules. The cholesterol sulfotransferase SULT2B1b catalyzes the sulfoconjugation of cholesterol to synthesize cholesterol sulfate (CS). In this study, we showed that the expression of SULT2B1b in the liver was induced in obese mice and during the transition from the fasted to the fed state, suggesting that the regulation of SULT2B1b is physiologically relevant. CS and SULT2B1b inhibited gluconeogenesis by targeting the gluconeogenic factor hepatocyte nuclear factor 4α (HNF4α) in both cell cultures and transgenic mice. Treatment of mice with CS or transgenic overexpression of the CS-generating enzyme SULT2B1b in the liver inhibited hepatic gluconeogenesis and alleviated metabolic abnormalities both in mice with diet-induced obesity (DIO) and in leptin-deficient (ob/ob) mice. Mechanistically, CS and SULT2B1b inhibited gluconeogenesis by suppressing the expression of acetyl coenzyme A (acetyl-CoA) synthetase (Acss), leading to decreased acetylation and nuclear exclusion of HNF4α. Our results also suggested that leptin is a potential effector of SULT2B1b in improving metabolic function. We conclude that SULT2B1b and its enzymatic by-product CS are important metabolic regulators that control glucose metabolism, suggesting CS as a potential therapeutic agent and SULT2B1b as a potential therapeutic target for metabolic disorders.     

Specular microscopy in glaucoma patients

The endothelial cells are one of the most important structures in a donor cornea. Morphology and concentration of endothelial cells must be carefully evaluated with a specular microscope before transplantation. The aim of this study is to evaluate the status of corneal endothelium in glaucoma patients. Prospective study included 50 patients suffering from glaucoma and 50 patients in control group. Patients had no corneal disease, ocular inflammation, previous trauma or ocular surgery. Patients were not contact lens wearers. They were also analyzed in groups according to type of glaucoma. Specular microscopy was performed on central corneas. This study showed that patients with glaucoma have lower central corneal endothelial cell density than those without glaucoma of the same age group. Also, patients with pseudoexfoliative glaucoma had lower values of central endothelial cell density comparing to patients with open angle or angle closure glaucoma.     

Effect of acute heat stress on rat adrenal medulla — a morphological and ultrastructural study

Isolated rat adrenal medulla was analyzed by light and electron microscope after an acute (60 min) exposure to high ambient temperature (38°C). Under these conditions there was a significant rise in plasma adrenaline and noradrenaline. Stereological investigation by light microscopy showed a significant decrease in volume density of cells and an increase in the interstitium. At the ultrastructural level, the profile area of cells, nuclei and cytoplasm of adrenaline cells were significantly decreased. After the heat stress numbers of resting granules in adre naline and noradrenaline cells were significantly reduced, while the numbers of altered granules and empty containers in both types of adrenomedullar cells were significantly increased.     

Identification of multiple HPV types on spermatozoa from human sperm donors

Human papillomaviruses (HPV) may cause sexually transmitted disease. High-risk types of HPV are involved in the development of cervical cell dysplasia, whereas low-risk types may cause genital condyloma. Despite the association between HPV and cancer, donor sperm need not be tested for HPV according to European regulations. Consequently, the potential health risk of HPV transmission by donor bank sperm has not been elucidated, nor is it known how HPV is associated with sperm. The presence of 35 types of HPV was examined on DNA from semen samples of 188 Danish sperm donors using a sensitive HPV array. To examine whether HPV was associated with the sperm, in situ hybridization were performed with HPV-6, HPV-16 and -18, and HPV-31-specific probes. The prevalence of HPV-positive sperm donors was 16.0% and in 66.7% of these individuals high-risk types of HPV were detected. In 5.3% of sperm donors, two or more HPV types were detected. Among all identified HPV types, 61.9% were high-risk types. In situ hybridization experiments identified HPV genomes particularly protruding from the equatorial segment and the tail of the sperm. Semen samples from more than one in seven healthy Danish donors contain HPV, most of them of high-risk types binding to the equatorial segment of the sperm cell. Most HPV-positive sperm showed decreased staining with DAPI, indicative of reduced content of DNA. Our data demonstrate that oncogenic HPV types are frequent in men.     

Extreme heterogeneity of polyadenylation sites in mRNAs encoding chloroplast RNA-binding proteins in Nicotiana plumbaginifolia

We have previously characterized nuclear cDNA clones encoding two RNA binding proteins, CP-RBP30 and CP-RBP-31, which are targeted to chloroplasts in Nicotiana plumbaginifolia. In this report we describe the analysis of the 3-untranslated regions (3-UTRs) in 22 CP-RBP30 and 8 CP-RBP31 clones which reveals that mRNAs encoding both proteins have a very complex polyadenylation pattern. Fourteen distinct poly(A) sites were identified among CP-RBP30 clones and four sites among the CP-RBP31 clones. The authenticity of the sites was confirmed by RNase A/T1 mapping of N. plumbaginifolia RNA. CP-RBP30 provides an extreme example of the heterogeneity known to be a feature of mRNA polyadenylation in higher plants. Using PCR we have demonstrated that CP-RBP genes in N. plumbaginifolia and N. sylvestris, in addition to the previously described introns interrupting the coding region, contain an intron located in the 3 non-coding part of the gene. In the case of the CP-RBP31, we have identified one polyadenylation event ocurring in this intron.     

Deletion polymorphism of the angiotensin I-converting enzyme gene in elderly patients with coronary heart disease

Controversy exists as to whether the deletion/deletion (DD) genotype of angiotensin l-converting enzyme (ACE) gene polymorphism is associated with coronary heart disease (CHD). There are only a few studies dealing with this issue in the elderly, also with controversial results. The aim of this study was the assessment of correlation between genetic markers and the risk of CHD in the elderly. The results indicated DD genotype importance for CHD in the elderly as proven by discriminant analysis (chi2 = 25.77; df = 16; p = 0.0620). However, the use of univariate method demonstrated no correlation between DD genotype of ACE gene polymorphism and coronary artery disease. D allele of ACE gene was associated with higher activities of ACE plasma. A weak, but increased risk of MI is associated with high frequency of DD genotype in the elderly. Strong correlation between ACE polymorphism and ACE plasma activities was demonstrated.     

Psychological status and coping with illness in patients with malignant melanoma

Melanoma patients are subject to different degrees of psychosocial distress. The emotional impact of malignant melanoma can be long lasting and profound, with the most common reactions to melanoma being depression, anxiety and deterioration in quality of life. Coping styles have been shown to have a significant influence on patients' quality of life and their emotional reaction to the illness. The aim of this paper was to investigate the quality of life, emotional status and coping styles in patients with melanoma. 31 patients suffering from malignant melanoma were included in the study. Results of this study show that melanoma has a medium influence on patients' psychological status and quality of life. The most "constructive" coping style--problem focused coping is the mostly used style by the patients, which might be one of the reasons why the illness didn't have a more severe influence on patients' psychological status.