Molecular analysis of 16 Turkish families with DHPR deficiency using denaturing gradient gel electrophoresis (DGGE)

Dihydropteridine reductase (DHPR) catalyses the conversion of quinonoid dihydrobiopterin (qBH2) to tetrahydrobiopterin (BH4), which serves as the obligatory cofactor for the aromatic amino acid hydroxylases. DHPR deficiency, caused by mutations in the QDPR gene, results in hyperphenylalaninemia and deficiency of various neurotransmitters in the central nervous system, with severe neurological symptoms as a consequence. We have studied, at the clinical and molecular levels, 17 patients belonging to 16 Turkish families with DHPR deficiency. The patients were detected at neonatal screening for hyperphenylalaninemia or upon the development of neurological symptoms. To identify the disease causing molecular defects, we developed a sensitive screening method that rapidly scans the entire open reading frame and all splice sites of the QDPR gene. This method combines PCR amplification and "GC-clamping" of each of the seven exonic regions of QDPR, resolution of mutations by denaturing gradient gel electrophoresis (DGGE), and identification of mutations by direct sequence analysis. A total of ten different mutations were identified, of which three are known (G23D, Y150C, R221X) and the remaining are novel (G17R, G18D, W35fs, Q66R, W90X, S97fs and G149R). Six of these mutations are missense variants, two are nonsense mutations, and two are frameshift mutations. All patients had homoallelic genotypes, which allowed the establishment of genotype-phenotype associations. Our findings suggest that DGGE is a fast and efficient method for detection of mutations in the QDPR gene, which may be useful for confirmatory DNA-based diagnosis, genetic counselling and prenatal diagnosis in DHPR deficiency.     

Antioxidant response of Chlamydomonas reinhardtii grown under different element regimes

Nutrient stress is one of the most favorable ways of increasing neutral lipid and high value‐added output production by microalgae. However, little is known about the level of the oxidative damage caused by nutrient stress for obtaining an optimal stress level for maximum production of specific molecules. In this study, the antioxidant response of Chlamydomonas reinhardtii grown under element deprivation (nitrogen, sulfur, phosphorus and magnesium) and supplementation (nitrogen and zinc) was investigated. All element regimes caused a decrease in growth, which was most pronounced under N deprivation. Element deprivation and Zn supplementation caused significant increases in H₂O₂ and lipid peroxidation levels of C. reinhardtii. Decrease in total chlorophyll level was followed by an increase of total carotenoid levels in C. reinhardtii under N and S deprivation while both increased under N supplementation. Confocal imaging of live cells revealed dramatic changes of cell shape and production of neutral lipid bodies accompanied by a decrease of chlorophyll clusters. Antioxidant capacity of cells decreased under N, S and P deprivation while it increased under N and Zn supplementation. Fluctuation of antioxidant enzyme activities in C. reinhardtii grown under different element regimes refers to different metabolic sources of reactive oxygen species production triggered by a specific element absence or overabundance.     

The antimicrobial activity of extracts of the lichen Hypogymnia tubulosa and its 3-hydroxyphysodic acid constituent

The antimicrobial activity and the MIC values of the diethyl ether, acetone, chloroform, petroleum ether, and ethanol extracts of the lichen Hypogymnia tubulosa and its 3-hydroxyphysodic acid constituent have been investigated against some microorganisms. At least one of the extracts or 3-hydroxyphysodic acid showed antimicrobial activity against Aeromonas hydrophila, Bacillus cereus, Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Listeria monocytogenes, Proteus vulgaris, Salmonella typhimurium, Staphylococcus aureus, Streptococcus faecalis, and Candida albicans. No antifungal activity of the extracts has been observed against ten filamentous fungi.     

Antimicrobial activity of extracts of chemical races of the lichen Pseudevernia furfuracea and their physodic acid, chloroatranorin, atranorin, and olivetoric acid constituents

The antimicrobial activity and the MIC values of the ethanol, chloroform, diethyl ether, and acetone extracts of the chemical races of Pseudevernia furfuracea (var. furfuracea and var. ceratea) and their physodic acid, chloroatranorin, atranorin, and olivetoric acid constituents have been investigated against some microorganisms. Nearly all extracts of both chemical races showed antimicrobial activity against Aeromonas hydrophila, Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Proteus vulgaris, Staphylococcus aureus, Streptococcus faecalis, Yersinia enterocolitica, Candida albicans, Candida glabrata, Alternaria alternata, Ascochyta rabiei, Aspergillus niger, Fusarium culmorum, Fusarium moniliforme, Fusarium oxysporum, Fusarium solani, and Penicillium notatum. There was no antimicrobial activity of the extracts against Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Pseudomonas syringae, Salmonella typhimurium, Alternaria citri, Alternaria tenuissima, and Gaeumannomyces graminis. Chloroatranorin and olivetoric acid were active against the same microorganisms with few exceptions. Physodic acid was active against about the same bacteria and yeasts and inactive against all of the filamentous fungi tested. Also no activity of atranorin against the filamentous fungi was observed.     

Comparative evaluation of western blotting in hepatic and pulmonary cystic echinococcosis

Many serological tests are widely used in the diagnosis of cystic echinococcosis (CE), caused by the larval stages of Echinococcus granulosus. The present study was carried for differentiation between hepatic and pulmonary cystic echinococcosis by Western Blotting (WB). A total of 121 sera from patients with hepatic CE (37), pulmonary CE (31) and controls (53; consisting of six healthy, seven Hymenolepis nana infection, 20 hepatic and 20 pulmonary diseases other than CE) were examined. In all of the CE patients, E. gronulosus infection was confirmed by surgical intervention. Sera were previously tested using IHA and ELISA to detect the E. gronulosus specific antibodies. Sera from hepatic cases of CE reacted with 16 polypeptides of 6-116 kDa and sera from pulmonary cases of CE reacted with 14 polypeptides of 4-130 kDa by Western Blotting. The WB test enabled the detection of antibodies in the hepatic CE samples for proteins of 24, 32 34, 44-46 and 52-54 kDa in molecular weight in 78.4%, 75.7%, 78.4% and 89.2% of the patients, respectively. In the pulmonary CE samples sera WB test enabled the detection of antibodies 24, 44-46, 100, 110, 116 and 120 124 kDa in molecular weight in 81.3%, 75.0%, 87.5%, 71.9%, 84.4% and 65.6% of the patients, respectively. We indicated that the antigenic components of high molecular weight can be good candidates for differentiation of hepatic CE from pulmonary CE.     

Paraoxonase 192 gene polymorphism and serum paraoxonase activity in high grade gliomas and meningiomas

The purpose of this study was to demonstrate the relationship between serum PON1 activity and PON 192 polymorphism in brain tumours. The distribution of PON 192 polymorphism in 42 high grade gliomas and 42 meningiomas were determined by polymerase chain reaction--based restriction fragment length polymorphism analysis and compared with 50 healthy control subjects. Serum paraoxonase1 activities were also measured and compared in the same population. We found that in both tumour groups serum PON1 activity was significantly lower than the control group (p < 0.001), but did not differ between meningiomas and high grade gliomas. There was no significant difference either in distribution of the AA, AB and BB genotypes or in the allelic frequencies, between the patient group and control subjects (p > 0.05). Our results suggest that serum PON1 as a part of the lipid peroxidation scavenging systems might be involved in the tumourigenesis of brain tumours.