PNA-induced assembly of fluorescent proteins using DNA as a framework

Controlled alignment of proteins on molecular frameworks requires the development of facile and orthogonal chemical approaches and molecular scaffolds. In this work, protein−PNA conjugates are brought forward as new chemical components allowing efficient assembly and alignment on DNA scaffolds. Site-selective monomeric teal fluorescent protein (mTFP)−peptide nucleic acid (PNA) (mTFP-PNA) conjugation was achieved by covalent linkage of the PNA to the protein through expressed protein ligation (EPL). A DNA beacon, with 6-Fam and Dabcyl at its ends, acts as a framework to create an assembled hetero-FRET system with the mTFP-PNA conjugate. Using fluorescence intensity, frequency domain lifetime measurements, and anisotropy measurements, the system was shown to produce FRET as indicated by decreased donor intensity, decreased donor lifetime, and increased donor anisotropy. Extension of the DNA scaffold allowed for the assembly of multiple mTFP-PNA constructs. Efficient formation of protein dimers and oligomers on the DNA-PNA frameworks could be shown, as visualized via size exclusion chromatography (SEC) and electrophoresis (SDS-PAGE). Assembly of multiple proteins in a row induced homo-FRET for the mTFP-PNA’s assembled on the DNA scaffolds. The oligonucleotide framework allows an induced and controllable assembly of proteins by fusing them to PNAs directed to align on DNA scaffolds

PNA-protein conjugates for nano-scale modeling of protein aggregates

Abstract Programmable assembly of proteins on molecular frameworks requires the development of facile and orthogonal chemical approaches and molecular scaffolds. In this research, the unique characteristics of PNA were applied to create controllable protein assemblies directed by precise PNA-DNA hybridization. The signatures of assembly were studied via FRET, providing a powerful tool which should be effective in live system imaging. Two model systems were developed in this study. In the first model system, site-selective conjugation of monomeric teal fluorescent protein (mTFP) to PNA was achieved by covalent linkage of mTFP to PNA via expressed protein ligation. The mTFP-PNA conjugates were efficiently aligned on a DNA beacon, to create a hetero-FRET system. The FRET indicated by decrease of fluorescence intensity and lifetime of the donor and an increase of donor anisotropy. The assembly of similar multiple mTFP-PNA constructs on DNA scaffolds provided dimeric and oligomeric forms which were studied by SEC-HPLC and SDS-PAGE. A decrease of anisotropy was exhibited due to homo-FRET following induced formation of dimers and oligomers. In the second model system, fluorescent SNAP-PNA conjugates were controllably assembled on DNA frameworks forming dimers and oligomers

Modelling peri-perceptual brain processes in a deep learning spiking neural network architecture

Familiarity of marketing stimuli may affect consumer behaviour at a peri-perceptual processing level. The current study introduces a method for deep learning of electroencephalogram (EEG) data using a spiking neural network (SNN) approach that reveals the complexity of peri-perceptual processes of familiarity. The method is applied to data from 20 participants viewing familiar and unfamiliar logos. The results support the potential of SNN models as novel tools in the exploration of peri-perceptual mechanisms that respond differentially to familiar and unfamiliar stimuli. Specifically, the activation pattern of the time-locked response identified by the proposed SNN model at approximately 200 milliseconds post-stimulus suggests greater connectivity and more widespread dynamic spatio-temporal patterns for familiar than unfamiliar logos. The proposed SNN approach can be applied to study other peri-perceptual or perceptual brain processes in cognitive and computational neuroscience

The Effect Of Cyperus Rotundus Ethanolic Extract On Motor Coordination In A Rat Model Of Alzheimer

Background and Objective: Alzheimer's disease (AD) is a degenerative disorder that leads to progressive cognitive decline. The memory dysfunction of AD has been associated with a cortical cholinergic deficiency and loss of cholinergic neurons of the nucleus basalis of Meynert (NBM). This study investigated the effect of ethanolic extract of Cyperus rotundu tubers (CRT) on motor activity in NBM-lesioned rat model of AD and intact rats. Materials and Methods: In this experimental study 49 Wistar rats were divided into 7 groups. For this purpose, Wistar rats received bilateral electric lesions of the NBM. The control and sham groups received distilled water while NBM-lesioned group received CRT extract for 20 days with doses of 100 and 200 mg/kg. Intact rats received CRT extract for 20 days without any surgery. The motor activity was assessed with Rotarod apparatus. Data were analyzed using one- way Anova and LSD test. Results: Use of ethanolic extract of CRT for 20 days improved motor activity in NBM-lesioned rats that received extract with a dose of 100 mg/kg. Ethanolic extract of CRT in the intact rats for 20 days significantly reduced motor activity when compared with the control group. Conclusion: The results of this study suggest that ethanolic extract of CRT is useful in NBM-induced lesion rats via inducing some changes in acetylcholine levels in the brain

Short communication: Infection of Aphanius dispar (Holly, 1929) with Ligula intestinalis plerocercoids in Mehran River, Hormuzgan province, south of Iran

Aphanius dispar (Holly, 1929) (known as Mahi gour-e khari, mahi dom parchami, kopurdandandar-e balehbolband) is an euryhaline tooth-carp fish which apparently prefers brackish waters of coastal areas of Iran. It is also distributed in Cyprus, Iraq, Somalia, Israel, Saudi Arabia, Syria and Djibouti. Aphanius dispar occurs in shallow water and among vegetation over sand, rock or soft detritus bottoms. Ligula intestinalis (L., 1758) is a pseudophyllidean cestode which in its plerocercoid stage infects a range of freshwater fish species, particularly members of the cyprinidae, as its second intermediate host and it has a widespread distribution throughout the northern hemisphere. However, no report is available on the occurrence of L. intestinalis from tooth-carp fish found in southern Iran. Recently, the present authors studied the infection of A. persicus in Barme-e-Shoor Spring-Stream System, Maharlu Basin, Shiraz, Iran. The present study was undertaken to investigate the possibility of A. dispar acting as an intermediate host for Ligula intestinalis from Mehran river in Mehran basin, near Bastak city, Hormuzgan Province, south of Iran

Effect of lavender on blood brain barrier permeability in rats subjected to ischemia

Background and purpose: Lavender is a medicinal plant with antioxidant activity. Stroke causes long term disability and is associated with oxidative stress. The present study was conducted to evaluate the protective effect of lavender extract against blood brain barrier permeability and its possible mechanisms in an experimental model of stroke. Materials and methods: In this experimental study, 42 male Wistar rats weighing 250 to 300 g were used. The rats were divided into 6 groups (n= 7 per group). Group 1 was ischemic, groups 2 and 3 were ischemic that were given 100 and 200 mg/kg lavender extract, respectively. Group 4 were intact and groups 5 and 6 were intact groups which received lavender extract with dose of 100 and 200 mg/kg. Group 7 was also considered as the sham. Focal cerebral ischemia was induced in rats by the transient occlusion of the middle cerebral artery for 1 hr. Data were analysed with SPSS and comparison of means were compared using One Way Anova. Results: The ethanolic extract of lavender at 200 mg/kg significantly reduced the blood brain barrier permeability in rat stroke model compared with ischemic group. Conclusion: The results indicate that lavender extract has neuroprotective activity against cerebral ischemia and alleviated neurological function in rats

Effect of early intervention on language development in hearing-impaired children

Introduction: Hearing loss from birth up to the age of 3 years has a negative effect on speech/language development and results in sensory, cognitive, emotional, and academic defects in adulthood by causing delayed development of communicative-linguistic abilities. The present study was performed in order to assess the effect of early intervention on language development in Persian children aged 6-7 years with severe sensorineural hearing loss. Materials and Methods: Thirty boys and girls aged 6-7 years participated in this study, all of them had severe congenital sensorineural hearing loss in both ears. All children were using bilateral behind-the-ear hearing aid, and had similar economic/socio-cultural backgrounds. Subjects were categorized into two groups based on the age of identification/intervention of hearing loss (3-6 and 12-15 months of age). The Persian TOLD-P3 test was used to evaluate language development in all subjects. Data collection was accomplished by observation, completion of questionnaires, and speech recording. Results: There was a significant difference in language development in 11 sub-tests and five lingual gains on the Persian TOLD-P3 test between early (3-6 months of age) and late identified/intervened (12-15 months of age) hearing-impaired children (P<0.05). Early identified/intervened hearing-impaired children had a notable preference in all assessed sub-tests and lingual gains. Conclusion: Early identification/intervention of hearing loss before the age of 6 months has a significant positive effect on a child's language development in terms of picture/relational/oral vocabulary, grammatical comprehension, sentence combining, grammatical completion, phonologic analysis, word differentiation, word production, semantics, and syntax. Moreover, early identification/ intervention of hearing loss develops the hearing-impaired child's lingual gains in visual vocabulary, grammatical completion, word differentiation, phonologic analysis, and word production

Antidepressant effects of mentha pulegium in mice

The aim of this study is to investigate the antidepressant effects of Mentha pulegium essential oil in BALB/ c mice. Six experimental groups (7 mice each) were used. Forced swim test was performed 30 min after essential oil injection. In the groups receiving M. pulegium essential oil (50, 75 and 100 mg/ kg), immobility duration significantly decreased compared to the control group. M. pulegium (50 and 75 mg/kg) resulted in significant decrease in nitrate/nitrite content in serum compared to the control group. M. pulegium essential oil antidepressant effect that may be due to the inhibition of oxidative stress. The results showed that decrease in nitrate/nitrite content in serum and high anti-oxidant effects of M. pulegium essential oil. © 2016, Bangladesh Pharmacological Society. All rights reserved

Multibody expansion of the local integrals of motion: How many pairs of particle-hole do we really need to describe the quasiparticles in the many-body localized phase?

The emergent integrability in a many-body localized (MBL) system can be well characterized by the existence of the complete set of local integrals of motion (LIOMs). Such exactly conserved and exponentially localized operators are often understood as quasiparticle operators which can be expanded in terms of single-particle operators dressed with different numbers of particle-hole pairs. Here, we consider a one-dimensional XXZ spin-$\frac12$ Heisenberg chain in the presence of a random field and try to quantify the corrections needed to be considered in the picture of quasiparticles associated with LIOMs due to the presence of particle-hole excitations. To this end, we explicitly present the multibody expansion of LIOM creation operators of the system in the MBL regime. We analytically obtain the coefficients of this expansion and discuss the effect of higher-order corrections associated with different numbers of particle-hole excitations. Our analysis shows that depending on the localization length of the system, there exist a regime in which the contributions that come from higher-order terms can break down the effective one-particle description of the LIOMs and such quasiparticles become essentially many-body-like