Whole mitochondrial DNA variations in hippocampal surgical specimens and blood samples with high-throughput sequencing: A case of mesial temporal lobe epilepsy with hippocampal sclerosis

Introduction

Hippocampal sclerosis is the most common lesion in patients with mesial temporal lobe epilepsy. Recently, there has been growing evidence on the involvement of mitochondria also in sporadic forms of epilepsy. In addition, it has been increasingly argued that mitochondrial dysfunction has an important role in epileptogenesis and seizure generation in temporal lobe epilepsy. Although mtDNA polymorphisms have been identified as potential risk factors for neurological diseases, the link between homoplasmy and heteroplasmy within tissues is not clear. We investigated whether mitochondrial DNA (mtDNA) polymorphisms are involved in a case report of a patient with mesial temporal lobe epilepsy-hippocampal sclerosis (MTLE-HS).

Design

We report the whole genome mtDNA deep sequencing results and clinical features of a 36-year-old woman with MTLE-HS. We used pyrosequencing technology to sequence a whole mitochondrial genome isolated from six different regions of her brain and blood. To assess the possible role of mitochondrial DNA variations in affected tissues, we compared all specimens from different regions of the hippocampus and blood.

Results

In total, 35 homoplasmic and 18 heteroplasmic variations have been detected in 6 different regions of the hippocampus and in blood samples. While the samples did not display any difference in homoplasmic variations, it has been shown that hippocampus regions contain more heteroplasmic variations than blood. The number of heteroplasmic variations was highest in the CA2 region of the brain and accumulated in ND2, ND4 and ND5 genes. Also, dentate and subiculum regions of the hippocampus had similar heteroplasmic variation profiles.

Discussion

We present a new rare example of parallel mutation at 16223 position. Our case suggests that defects in mitochondrial function might be underlying the pathogenesis of seizures in temporal lobe epilepsy.     

A new set up for multi-analyte sensing: at-line bio-process monitoring

A multi-analyte sensing device is described, for simultaneous at-line monitoring of glucose, ethanol, pO?-value and cell density. It consists of a dual biosensor, a modified microscope and a fiber optical pO?-sensor that are integrated into a flow analysis (FA) system. The biosensor is based on a conventional thin layer flow-through cell equipped with a gold (Au) dual electrode (serial configuration). The biosensors with no cross-talking were produced by modifying the electrochemical transducers. Each Au surface was initially modified by self-assembled monolayer (SAM) of cysteamine. Alcohol oxidase (AOx) and pyranose oxidase (PyOx) were immobilized each onto a gold surface by means of PAMAM (polyamidoamine) dendrimer via glutaraldehyde cross-linking. The responses for glucose and ethanol were linear up to 0.5 mM. The operational stability of the biosensors was very promising, after 11 h continuous operation, only 6.0% of the initial activity was lost. The potential of the described biosensor was demonstrated by parallel determination of ethanol and glucose in yeast fermentation process. Simultaneously the cell density of the culture was monitored with an in situ microscope (ISM), which was integrated into the FA system. Both the used in situ microscope and the image processing algorithm used for the analysis of the acquired image data are described. Furthermore the pO?-value was monitored using a fiber optical sensor, which was embedded in a flow cell. The multi-sensor device allows the at-line monitoring of several process values without the need for further sampling or time consuming offline measurements.     

Amelogenesis Imperfecta in Two Families with Defined AMELX Deletions in ARHGAP6

Amelogenesis imperfecta (AI) is a group of inherited conditions featuring isolated enamel malformations. About 5% of AI cases show an X-linked pattern of inheritance, which are caused by mutations in AMELX. In humans there are two, non-allelic amelogenin genes: AMELX (Xp22.3) and AMELY (Yp11.2). About 90% of amelogenin expression is from AMELX, which is nested within intron 1 of the gene encoding Rho GTPase activating protein 6 (ARHGAP6). We recruited two AI families and determined that their disease-causing mutations were partial deletions in ARHGAP6 that completely deleted AMELX. Affected males in both families had a distinctive enamel phenotype resembling “snow-capped” teeth. The 96,240 bp deletion in family 1 was confined to intron 1 of ARHGAP6 (g.302534_398773del96240), but removed alternative ARHGAP6 promoters 1c and 1d. Analyses of developing teeth in mice showed that ARHGAP6 is not expressed from these promoters in ameloblasts. The 52,654 bp deletion in family 2 (g.363924_416577del52654insA) removed ARHGAP6 promoter 1d and exon 2, precluding normal expression of ARHGAP6. The male proband of family 2 had slightly thinner enamel with greater surface roughness, but exhibited the same pattern of enamel malformations characteristic of males in family 1, which themselves showed minor variations in their enamel phenotypes. We conclude that the enamel defects in both families were caused by amelogenin insufficiency, that deletion of AMELX results in males with a characteristic snow-capped enamel phenotype, and failed ARHGAP6 expression did not appreciably alter the severity of enamel defects when AMELX was absent.     

A unified atlas of CD8 T cell dysfunctional states in cancer and infection

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Association between selected cholesterol-related gene polymorphisms and Alzheimer’s disease in a Turkish cohort

Molecular Biology Reports - Numerous genetic evidence has pointed out that variations in cholesterol-related genes may be associated with an Alzheimer’s disease (AD) risk. We aimed to...     

Comparison of fatty acids and some mineral matter profiles of wild and farmed snails,Cornu aspersum Müller, 1774

ABSTRACT

The fatty acid and mineral matter compositions of the visceral mass and pedal mass of wild and farmed Cornu aspersum were compared. The relative fatty acid amounts of the visceral and pedal masses of wild and farmed snails are: polyunsaturated fatty acid (PUFA) > saturated fatty acid (SFA) > monounsaturated fatty acid (MUFA), PUFA?>?SFA?>?MUFA, MUFA?>?PUFA?>?SFA and PUFA?>?MUFA?>?SFA, respectively. Wild snails had a higher concentration of iron and zinc than farmed snails. Selenium was 2.82 times higher in the pedal mass of farmed snails than the pedal mass of wild snails. Ca:P ratios in the visceral mass of wild snails, visceral mass and pedal mass of farmed snails were 1.76:1, 1.12:1 and 3.87:1 respectively. Both wild and farmed snails have high contents of oleic, linoleic, eicosapentaenoic and docosahexaenoic fatty acids and are a good source of minerals. Careful attention should be paid, however, as to which diet will be used during farming because the composition of fatty acid in the snail is affected by diet.     

TRPM3 Expression in Mouse Retina

Transient receptor potential (TRP) channels constitute a large family of cation permeable ion channels that serve crucial functions in sensory systems by transducing environmental changes into cellular voltage and calcium signals. Within the retina, two closely related members of the melastatin TRP family, TRPM1 and TRPM3, are highly expressed. TRPM1 has been shown to be required for the depolarizing response to light of ON-bipolar cells, but the role of TRPM3 in the retina is unknown. Immunohistochemical staining of mouse retina with an antibody directed against the C-terminus of TRPM3 labeled the inner plexiform layer (IPL) and a subset of cells in the ganglion cell layer. Within the IPL, TRPM3 immunofluorescence was markedly stronger in the OFF sublamina than in the ON sublamina. Electroretinogram recordings showed that the scotopic and photopic a- and b-waves of TRPM3^-/- mice are normal indicating that TRPM3 does not play a major role in visual processing in the outer retina. TRPM3 activity was measured by calcium imaging and patch-clamp recording of immunopurified retinal ganglion cells. Application of the TRPM3 agonist, pregnenolone sulfate (PS), stimulated increases in intracellular calcium in ~40% of cells from wild type and TRPM1^‑/‑ mice, and the PS-stimulated increases in calcium were blocked by co-application of mefenamic acid, a TRPM3 antagonist. No PS-stimulated changes in fluorescence were observed in ganglion cells from TRPM3^-/- mice. Similarly, PS-stimulated currents that could be blocked by mefenamic acid were recorded from wild type retinal ganglion cells but were absent in ganglion cells from TRPM3^-/- mice.     

Recurrence patterns of pancreatic cancer treated with adjuvant intensity modulated radiotherapy

BackgroundThe aim of this study was to investigate the recurrence patterns in pancreatic cancer patients treated with adjuvant intensity modulated radiotherapy (IMRT) and to correlate the sites of locoregional recurrence with radiotherapy target volumes.Materials and methodsThirty-eight patients who had undergone resection and adjuvant chemoradiation for pancreatic cancer were evaluated. Radiotherapy (RT) was started after 1–3 cycles of adjuvant chemotherapy (CHT). Clinical target volume (CTV) was contoured according to the RTOG guideline. All patients were treated with IMRT with a dose of 45–50.4 Gy. Computerized tomography (CT) images at the time of recurrence were correlated with radiotherapy plans. Locoregional recurrences were classified as in-field, out-field and marginal.ResultsMedian overall survival (OS) was 19 months. One- and 2-year OS rates were 73.6% and 37.1%, respectively. Locoregional recurrence and distant metastases were observed in 11 (28.9%) and 23 (60.5%) patients, respectively. For the 11 locoregional recurrences, 7 were in-field, 1 was marginal, and 3 were out-of-field. One patient had isolated local, 2 patients had isolated regional and 15 (57.6%) patients had only distant failures. The first presentations of failures were mostly distant (58%). On multivariate analysis, tumor size ≥ 3 cm (p = 0.011) and positive vascular invasion (p = 0.014) predicted for worse OS rate.ConclusionsThe majority of locoregional recurrences were in the radiation field among pancreatic cancer patients treated with postoperative IMRT. However, failures were predominantly distant, and improvement of systemic control may be of particular interest.