Increased expression of matrix metalloproteinase-9 in patients with temporal lobe epilepsy

Aim: The molecular mechanism of epileptogenesis in temporal lobe epilepsy is still unclear. Experimental studies have suggested that matrix metalloproteinases have important roles in this process, but human studies are limited. The aim of this study was to assess the expression of MMP-9, MMP-2 and their tissue inhibitors (TIMP-1 and TIMP-2) in patients with temporal lobe epilepsy with hippocampal sclerosis (TLE-HS). Material and Methods: The tissue samples from temporal neocortex and hippocampus were obtained from patients with temporal lobe epilepsy with hippocampal sclerosis who had undergone anterior temporal lobectomy for recurrent medically resistant seizures. Immunohistochemical methods were used to determine the expression of MMP-9, MMP-2 and their tissue inhibitors. Tissue samples were also analyzed with transmission electron microscopy. Results: The immunoreactivity for MMP-9 both in hippocampal and temporal neocortical neurons was stronger than that of MMP-2. Additionally, there was a mild reaction for its tissue inhibitor TIMP-1 as with TIMP-2. The TEM analysis of the hippocampus revealed that there was apparent ultra-structural damage on the pericarya and neuropil of some neurons. There was obvious damage in the mitochondria and the nuclear membrane. Conclusion: The preliminary results of this study revealed that MMP-9 may have a role in patients with drug resistant TLE-HS

Repairing the Digital Divide Can Increase the Service Divide: The Effects of Patient Portals on Kidney Allocation

The severe shortage of organs combined with increasing demand for them characterizes the outcomes for the kidney allocation process. Despite the efforts to improve the allocation of kidneys, notable inefficiencies and unequal access to available organs persist across patient populations. The goal of this study is to examine (i) whether the adoption of a patient-oriented information technology (IT), namely the patient portals, can mitigate inefficiencies in the allocation of these scarce resources (kidneys) in general; (ii) whether the adoption of patient portals magnify or alleviate the disparity issues around access to transplants. Using a rich dataset of all the kidney transplant records in the U.S. from 2011 to 2014, we show that the likelihood that the patient receives deceased donor transplant at a given point in time increases in the presence of patient portals. However, the varying impact of IT across sub-populations may indicate that the efforts to bridge the digital divide may benefit some groups of patients at the expense of other groups, leading to further disparities

Podwójne znakowanie immunologiczne CD133 i Ki-67 wskazuje na ich istotną współlokalizację w podtypie włóknistym oponiaków

Background and purpose A unique molecular and/or cellular marker for meningiomas, the most common intracranial tumours, has not been identified yet. Material and methods We investigated the co-localization fraction of CD133/Ki-67 in meningioma tissue array slide composed of 80 meningioma tissue samples of various histological variants. CD133 – a cell membrane stem cell marker – was previously proved to be associated with the initiation and progression of intracerebral gliomas and medulloblastomas. Results Immunohistochemical co-localization of CD133/Ki-67 was significantly higher in fibroblastic variant than in meningothelial and transitional subtypes. However, since there were only 3 atypical and 1 malignant meningioma spots in the tumour tissue array slide, it is difficult to draw a firm conclusion regarding the actual co-localization percentage and persistence of CD133/Ki-67 in atypical and malignant meningiomas. Conclusions Far higher co-staining percentage of CD133/Ki-67 in fibroblastic meningioma samples compared to meningothelial subtype, a histological meningioma variant, architectonically resembling the non-neoplastic meningeal cells, gave us the impression that CD133 may play a role in the formation and progression of fibroblastic meningioma variants. The persistency and the validity of this finding need to be verified by further histopathological and molecular research in order to clarify the possible role of CD133 in meningiogenesis.Wstęp i cel pracy Nie określono dotąd unikalnego znacznika molekularnego lub komórkowego dla oponiaków, najczęstszych guzów wewnątrzczaszkowych. Wcześniej wykazano, że CD133 – znacznik błony komórkowej komórek macierzystych – jest związany z zapoczątkowaniem, a także wzrostem wewnątrzczaszkowych glejaków i rdzeniaków płodowych. Materiał i metody Zbadano odsetek współlokalizacji CD133/Ki-67 w zestawach macierzy tkankowych oponiaków, złożonych z próbek 80 rozmaitych odmian histologicznych oponiaków. Wyniki Immunohistochemiczna współlokalizacja CD133 i Ki-67 była stwierdzana istotnie częściej w podtypie włóknistym oponiaka niż w podtypach meningotelialnym lub przejściowym. Ze względu na małą liczbę preparatów opo-niaków atypowych (3) oraz złośliwych (1) w badanej macierzy tkankowej trudno wyciągnąć jednoznaczne wnioski dotyczące rzeczywistego odsetka współlokalizacji i utrzymywania się CD133/Ki-67 w oponiakach atypowych i złośliwych. Wnioski Znacząco większy odsetek wspólnie występującej reaktywności CD133/Ki-67 w preparatach oponiaka włóknistego w porównaniu z podtypem meningotelialnym, którego architektonika przypomina nienowotworowe komórki opon, sprawia wrażenie, że CD133 może odgrywać rolę w powstawaniu i rozwoju oponiaków włóknistych. Trafność tego spostrzeżenia wymaga weryfikacji w dalszych badaniach histopatologicznych i molekularnych w celu wyjaśnienia możliwej roli CD133 w powstawaniu oponiaków

Neuronal nitric oxide synthase phosphorylation induced by docosahexaenoic acid protects dopaminergic neurons in an experimental model of Parkinson’s disease

Introduction. Docosahexaenoic acid (DHA) has been shown to have beneficial effects on Parkinson’s disease(PD). The aim of this study was to investigate if the DHA acts on neurons of substantia nigra (SN) by phosphorylation of neuronal nitric oxide synthase (nNOS) in an experimental mouse model of PD.Material and methods. An experimental model of PD was created by intraperitoneal injections (4 × 20 mg/kg)of the neurotoxin 1-methyl-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP). Three-month-old male C57BL/6 micewere randomly divided into four groups as follows: control (C), DHA-treated (DHA), MPTP-injected (MPTP)and DHA-treated and MPTP-injected (DHA + MPTP). DHA (36 mg/kg/day) was administered daily by gavagefor four weeks. Motor activity of the mice was evaluated with pole, locomotor activity and rotarod tests. Caspase-3activity, nitrate/nitrite and 4-hydroxynonenal (4-HNE) levels were determined by spectrophotometric assays.Immunohistochemistry was used to localize and assess the expressions of tyrosine hydroxylase (TH), nNOS andphospho-nNOS (p-nNOS) in SN.Results. An increased return and total down time in the MPTP group was observed in the pole test, while DHAtreatment decreased both parameters. The ambulatory activity, total distance and total locomotor activities weredecreased in the MPTP group, whereas they were increased by DHA treatment. MPTP-treated animals exhibitedshorter time on the rod test which was significantly increased by DHA treatment. DHA administration significantlydecreased 4-HNE and nitrate/nitrite levels of SN supernatants and protected the TH (+) dopaminergicneurons of SN in the DHA + MPTP group compared to the MPTP group. DHA treatment significantly decreasednNOS and increased p-nNOS immunoreactivities in the DHA + MPTP group compared to the MPTP group.Conclusions. These results indicate that DHA treatment protects dopaminergic neurons in SN via increasingnNOS serine 852 phosphorylation in the experimental mice model of PD

Effects of excess vitamin B6 intake on cerebral cortex neurons in rat: an ultrastructural study

The aim of this study was to investigate whether excess of vitamin B6 leads to ultrastructural changes in cerebral cortex of forty-eight healthy albino rats which were included in the study. Saline solution was injected to to the control groups (CG-10, n=12 for 10 days; CG-15, n=12 for 15 days; CG-20, n=12 for 20 days). The three experimental groups (EG-10, n=12; EG-15, n=12; EG-20, n=12) were treated with 5 mg/kg vitamin B6 daily for 10 days (EG-10), 15 days (EG-15) and 20 days (EG-20). Brain tissues were prepared by glutaraldehyde-osmium tetroxide double fixation for ultrastructural analysis. No significant changes were observed in the control groups. The ultrastructural analysis revealed that the numbers of damaged mitochondria, lipofuscin granules and vacuoles were significantly higher in all the experimental groups than in the control groups (

On the Optimization of Iterative Clipping and Filtering for PAPR Reduction in OFDM Systems

Orthogonal frequency division multiplexing (OFDM) offers spectral efficiency advantage, however, it is limited by peak-to-average power (PAPR) problem. The PAPR can be reduced using iterative clipping and filtering (ICF) scheme but requires that the same signals are iteratively clipped with a fixed clipping threshold at different clipping iterations. This method warrants that fast-Fourier transform (FFT)/inverse FFT (IFFT) blocks must be driven in the order of iterations many times to attain a desired PAPR threshold which expends the system power and expands the processing time. Using a second-order cone program, the number of iterations required to attain the desired PAPR threshold was reduced. This optimized ICF (OICF) was later simplified using Lagrange multiplier (LM). In this paper, we apply an adaptive clipping threshold to the LM scheme to improve the performance of the simplified OICF (SOICF). Our results show significant reduction of the PAPR problem compared with the earlier SOICF scheme albeit with some degradation in the bit error ratio (BER) performance that can be under 1.0 dB depending on the chosen clipping threshold. In addition, we also illustrate the results of the performances and the theoretical relationships between the error vector magnitude (EVM) and PAPR, between clipping ratio (CR) and EVM, and lastly the inter-dependencies of EVM, PAPR, the number of OFDM subcarriers, and the CR