Mitochondrial DNA profiling via genomic analysis in mesial temporal lobe epilepsy patients with hippocampal sclerosis

Introduction

Mitochondria have an essential role in neuronal excitability and neuronal survival. In addition to energy production, mitochondria also play a crucial role in the maintenance of intracellular calcium homeostasis, generation of reactive oxygen species and mechanisms of cell death. There is a relative paucity of data about the role of mitochondria in epilepsy. Mitochondrial genome analysis is rarely carried out in the investigation of some diseases. In mesial temporal lobe epilepsies (MTLE) cases, genome analysis has never been used previously. The aim of this study is to show mitochondrial dysfunctions using genome analysis in patients with MTLE-hippocampal sclerosis (HS).

Methods

44 patients with MTLE-HS and 86 matched healthy unrelated controls were included in this study. The patients were divided into four groups according to their clinical presentation as the following: Group 1 consists of patients with intractable epilepsy who refused operation; Group 2 of operated seizure free patients; Group 3 of operated patients with seizures; and Group 4 unoperated seizure free patients with or without antiepileptic drugs. Blood samples were used to isolate DNA. Parallel tagged sequencing was employed to allow pyrosequencing of 130 samples. Complete mtDNA is amplified in two overlapping fragments (11 and 9 kb). The PCR amplicons were pooled in equimolar ratios. Titanium kits were used to produce shotgun libraries according to the manufacturer's protocol.

Results

The average coverage in total was 130 ± 30 and an average of 2365127 bases and 337 bp fragment length was received from all samples. The mean mtDNA heteroplasmy in patients was 26.35 ± 12.3 and in controls 25.03 ± 9.34. Three mutations had prominently high significance in patient samples. The most significantly associated variation was located in the MT-ATP-8 gene (8502 A > T, Asn46Ile) whereas the other two were in the MT-ND4 (11994 C > T, Thr412Ile) and MT-ND5 (13231 A > C, Lys299Gln) genes.

Conclusions

We have observed that three mutations were significantly related to the presence of epilepsy. These mutations were found at the 8502, 11994, and 13231 bp of mtDNA, which resulted in amino acid changes at the MT-ATP-8, MT-ND4 and MT-ND5 genes. Finding mutations can lead us to knowing more about the pathophysiology of the MTLE disease.     

Combined effects of collagen type I alpha1 (COL1A1) Sp1 polymorphism and osteoporosis risk factors on bone mineral density in Turkish postmenopausal women

Identification of risk factors for osteoporosis has been essential for understanding the development of osteoporosis. The collagen type I alpha1 (COL1A1) gene is suggested to be implicated in reduced bone mineral density (BMD) in osteoporosis. In the present study, the investigation of the effects of Sp1 polymorphic variants of COL1A1 gene on BMD values, and the determination of the association between COL1A1 Sp1 gene variants and osteoporosis risk factors in the context of gene–environment interaction in Turkish postmenopausal women were aimed. For the detection of COL1A1 Sp1 polymorphism, PCR-RFLP techniques have been used. BMD for lumbar spine (L1–L4) and hip (femoral neck and total hip) was measured by DXA. This study was carried out using a sample of 254 postmenopausal women. We observed a trend decrease in BMD values in the subjects with “ss” genotype having lower BMD of lumbar spine, femoral neck and total hip than those with “SS” and “Ss” genotype, however the differences did not reach statistical significance (P > 0.05). We also found that the frequencies of the BMD under mean values at the femoral neck (57.5%) and total hip (76.2%) increased considerably in the subjects carrying “Ss/ss” genotypes in combination of having family history of osteoporosis (61.5% for femoral neck) and smoking history (90.0% for total hip). This population-based study indicates that COL1A1 Sp1 polymorphism may contribute to the development of osteoporosis in combination of osteoporosis risk factors in Turkish postmenopausal women.     

The Effect of Cisplatin Toxicity and Capsaicin on Electron Transport Chain in Liver and Kidney of Sprague Dawley Rats

Cisplatin accumulates in mitochondria, which is a potent and widely used chemotherapeutic agent. In order to clarify the potential effect of cisplatin on electron transport chain (ETC), the variation of succinate dehydrogenase (SDH) and cytochrome c oxidase (COX) enzyme activities, nucleotide levels, as well as catalase (CAT) enzyme and membrane lipid peroxidation (LPO) level with respect to liver and kidney of cisplatin-exposed rats were studied. We found that cisplatin caused significant impairment in the SDH, COX, and CAT activities, and nucleotide levels associated with membrane LPO in isolated mitochondria. It was determined whether capsaicin, as an antioxidant, has a possible protective role on all investigated parameters of liver and kidney induced by cisplatin. The results of capsaicin + cisplatin suggest that capsaicin have antioxidant capacity to scavenge ROS to prevent membrane damage.     

The interrelations of radiologic findings and mechanical ventilation in community acquired pneumonia patients admitted to the intensive care unit: a multicentre retrospective study

Background

Burkholderia cepacia complex (BCC) bacteria are highly virulent, typically multidrug-resistant, opportunistic pathogens in cystic fibrosis (CF) patients and other immunocompromised individuals. B. vietnamiensis is more often susceptible to aminoglycosides than other BCC species, and strains acquire aminoglycoside resistance during chronic CF infection and under tobramycin and azithromycin exposure in vitro, apparently from gain of antimicrobial efflux as determined through pump inhibition. The aims of the present study were to determine if oxidative stress could also induce aminoglycoside resistance and provide further observations in support of a role for antimicrobial efflux in aminoglycoside resistance in B. vietnamiensis.

Findings

Here we identified hydrogen peroxide as an additional aminoglycoside resistance inducing agent in B. vietnamiensis. After antibiotic and hydrogen peroxide exposure, isolates accumulated significantly less [³H] gentamicin than the susceptible isolate from which they were derived. Strains that acquired aminoglycoside resistance during infection and after exposure to tobramycin or azithromycin overexpressed a putative resistance-nodulation-division (RND) transporter gene, amrB. Missense mutations in the repressor of amrB, amrR, were identified in isolates that acquired resistance during infection, and not in those generated in vitro.

Conclusions

These data identify oxidative stress as an inducer of aminoglycoside resistance in B. vietnamiensis and further suggest that active efflux via a RND efflux system impairs aminoglycoside accumulation in clinical B. vietnamiensis strains that have acquired aminoglycoside resistance, and in those exposed to tobramycin and azithromycin, but not hydrogen peroxide, in vitro. Furthermore, the repressor AmrR is likely just one regulator of the putative AmrAB-OprM efflux system in B. vietnamiensis.     

Determining Toxoplasma high-risk autologous and allogeneic hematopoietic stem cell transplantation patients by systematic pre-transplant PCR screening of stem cell originated buffy coat

The diagnosis of Toxoplasma infection or disease in hematopoietic stem cell transplantation (HSCT) patients is achieved mainly by PCR screening; however screening did not find wide field of use in practice due to costly expenditures of PCR. This study aimed to determine patients at high risk of Toxoplasma infection or disease before transplantation by stem cell originated buffy coat PCR and subsequently to screen them. Buffy coats collected from 12 autologous and 18 allogeneic HSCT patients' donors were investigated by PCR before transplantation. After transplantation, blood and sera collected at fixed time intervals were screened by two PCR methods and serological assays. Screening results first time assessed a toxoplasmosis incidence level as 25% in autologous HSCT patients and increased incidence level in allogeneic HSCT patients to 22%. Importantly, buffy coat PCR was first time performed before transplantation, to determine the risk of toxoplasmosis. Buffy coat PCR results showed that four patients were at high risk of toxoplasmosis before transplantation. After transplantation, these patients experienced toxoplasmosis. In conclusion, for the determination of patients at risk of toxoplasmosis, clinicians should consider buffy coat PCR in combination with serology before transplantation. After transplantation, PCR screening can be initiated in high risk patients upon clinical suspicion.     

Is there any association between GLY82 ser polymorphism of rage gene and Turkish diabetic and non diabetic patients with coronary artery disease?

This study was carried out in 52 non-diabetic, 62 diabetic patients with coronary artery disease (CAD) and 55 controls. A Gly to Ser change RAGE gene was analyzed by PCR-RFLP techniques. GlyGly genotype frequency is higher in non-diabetics versus controls (P < 0.001). GlySer frequency is higher in diabetics than controls and non-diabetics (P < 0.001). Ser allele frequency is respectively increased in the order of diabetics > Controls > non-diabetics. These results reveals none association between Gly82Ser and the development of disease in non-diabetic patients. In diabetics with Ser allele, higher prevalence of left-ventricule-hypertrophy was observed, but the significant difference between Gly82Ser and left-ventricule-hypertrophy only found in the whole patient group. As a result Ser allele has much more importance in the development of left-ventricule-hypertrophy than other cardiovascular risk factors. In this study we found the presence of Gly allele contributes to the CAD in non-diabetics and Ser allele may contribute to disease in diabetics.     

Expression of ERCC1 and its clinicopathological correlations in non-small cell lung cancer

Excision Repair Cross-Complementing Group 1 (ERCC1) is an important DNA repair gene, playing critical role in nucleotide excision repair pathway and having a significant influence on genomic instability. Some studies support that ERCC1 might be a potential predictive and prognostic marker in non-small cell lung cancer (NSCLC). ERCC1 has also been shown to be a promising biomarker in NSCLC treated with a cisplatin-based regimen. Therefore, the determination of ERCC1 expression at DNA, mRNA and protein level in different stages of NSCLC is still an important topic in the cancer. Ninety-one formalin-fixed paraffin-embedded tumor samples histopathologically diagnosed as NSCLC were examined in this study. ERCC1 expression at protein level were scored by immunohistochemistry. The gene amplification and mRNA expression levels for ERCC1 were determined by real-time quantitative PCR. There was complete concordance among the three methods in 39 tumor samples (42.9%). A strong correlation was found between DNA amplification and mRNA expression (r = 0.662) while there was no correlation between mRNA and protein assessment for ERCC1 expression (r = −0.013). ERCC1 expression at mRNA and DNA level (63.1 and 84.2%, respectively) in tumors at stage III was higher than at the other stages. In contrast, the protein expression at stage II and III (56.6 and 52.6%, respectively) of NSCLC was lower than that of tumors with stage I NSCLC. These results show that the mechanism by which ERCC1 expression might play a role in tumor behavior. This study was also confirmed that the appropriate validation and qualification in methods used for ERCC1 status were needed before its clinical application and implementation.     

Prevalence of known mutations and a novel missense mutation (M694K) in the MEFV gene in a population from the Eastern Anatolia Region of Turkey

Familial Mediterranean fever (FMF) is an autosomal recessive disorder characterized by recurrent attacks of fever and serositis. Mutations in the Mediterranean fever gene (MEFV) localized on the short arm of chromosome 16 cause FMF. Over 90 MEFV missense/nonsense mutations have been identified so far in FMF patients, mostly in the 10th exon of the gene.     

Comparison of some properties of free and immobilized alpha-amylase by Aspergillus sclerotiorum in calcium alginate gel beads

Some properties of immobilized alpha-amylase by Aspergillus sclerotiorum within calcium alginate gel beads were investigated and compared with soluble enzyme. Optimum pH and temperature were found to be 5.0 and 40 degrees C, respectively, for both soluble and immobilized enzymes. The immobilized enzyme had a better Km value, but kcat/Km values were the same for both enzymes. Entrapment within calcium alginate gel beads improved, remarkably, the thermal and storage stability of alpha-amylase. The half life values of immobilized enzyme and soluble enzyme at 60 degrees C were 164.2, and 26.2 min, respectively. The midpoint of thermal inactivation (Tm) shifted from 56 degrees C (for soluble enzyme) to 65.4 degrees C for immobilized enzyme. The percentages of soluble starch hydrolysis for soluble and immobilized alpha-amylase were determined to be 97.5 and 92.2% for 60 min, respectively.