Long-Term Recording of LTP in Cultured Hippocampal Slices

Long-term potentiation (LTP) was elicited by high frequency stimulation in hippocampal slices cultured on multi-electrode arrays. LTP lasting more than 1 h was recorded in 75% of slices, and a significant number of slices exhibited a non-decaying LTP that lasted more than 48 h. LTP induction was completely and reversibly blocked by an antagonist of the NMDA receptor, APV. Our results suggest the possibility of using chronic recording in hippocampal slices cultured on multi-electrode arrays to study the mechanisms underlying LTP maintenance and stabilization

Kinetics of thorium and particle cycling along the U.S. GEOTRACES North Atlantic Transect

© The Author(s), 2017. This is the author's version of the work. It is posted here under a nonexclusive, irrevocable, paid-up, worldwide license granted to WHOI. It is made available for personal use, not for redistribution. The definitive version was published in Deep Sea Research Part I: Oceanographic Research Papers 125 (2017): 106-128, doi:10.1016/j.dsr.2017.05.003.The high particle reactivity of thorium has resulted in its widespread use in tracing processes impacting marine particles and their chemical constituents. The use of thorium isotopes as tracers of particle dynamics, however, largely relies on our understanding of how the element scavenges onto particles. Here, we estimate apparent rate constants of Th adsorption (k1), Th desorption (k−1), bulk particle degradation (β-1), and bulk particle sinking speed (w) along the water column at 11 open-ocean stations occupied during the GEOTRACES North Atlantic Section (GA03). First, we provide evidence that the budgets of Th isotopes and particles at these stations appear to be generally dominated by radioactive production and decay sorption reactions, particle degradation, and particle sinking. Rate parameters are then estimated by fitting a Th and particle cycling model to data of dissolved and particulate 228,230,234Th, 228Ra, particle concentrations, and 234,238U estimates based on salinity, using a nonlinear programming technique. We find that the adsorption rate constant (k1) generally decreases with depth across the section: broadly, the time scale 1/k1 averages 1.0 yr in the upper 1000 m and (1.4–1.5) yr below. A positive relationship between k1 and particle concentration (P) is found, i.e., , k1 ∝ Pb where b ≥ 1, consistent with the notion that k1 increases with the number of surface sites available for adsorption. The rate constant ratio, K = k1/(k-1 + β-1), which measures the collective influence of rate parameters on Th scavenging, averages 0.2 for most stations and most depths. We clarify the conditions under which K/P is equivalent to the distribution coefficient, KD, test that the conditions are met at the stations, and find that decreases with P, in line with a particle concentration effect (dKD/dP < 0). In contrast to the influence of colloids as envisioned by the Brownian pumping hypothesis, we provide evidence that the particle concentration effect arises from the joint effect of P on the rate constants for thorium attachment to, and detachment from, particles.We acknowledge the U.S. National Science Foundation for providing funding for this study (grant OCE-1232578) and for U.S. GEOTRACES North Atlantic section ship time, sampling, and data analysis. The U.S. NSF also supported the generation of 230Th data (OCE-0927064 to LDEO, OCE-O092860 to WHOI, and OCE-0927754 to UMN) and 228,234Th data (OCE-0925158 to WHOI)

In-Plane Behavior of Cold-Formed Steel-Framed Shear Wall Panels Sheathed with Fibre Cement Board

Shear wall panels are commonly used as lateral load resisting elements to provide stability of the cold-formed steel-framed houses in Australia against wind and earthquake actions. The effectiveness of their lateral resistance behavior is obtained usually by experimental testing although it can also be done by analytical modeling. This paper presents racking test results of steelframed wall panels with different aspect ratios sheathed with fibre cement board subjected to monotonic and cyclic loading protocol. Performance parameters of the wall panels are obtained from the experimentally observed load-deflection curves using various existing methods and evaluation method is proposed. The evaluation method considers various performance characteristics including ductility modification factor, residual displacement recovery and load levels satisfying ultimate and serviceability limit state conditions

Use of drug therapy in the management of symptomatic ureteric stones in hospitalized adults (SUSPEND), a multicentre, placebo-controlled, randomized trial of a calcium-channel blocker (nifedipine) and an α-blocker (tamsulosin) : study protocol for a randomized controlled trial

Peer reviewedPublisher PD

Neuroprotective effects of ginsenosides Rh1 and Rg2 on neuronal cells

<p>Abstract</p> <p>Background</p> <p>The present study investigates the effects of ginsenosides Rh₁and Rg₂against 6-hydroxydopamine (6-OHDA), a neurotoxin on SH-SY5Y cells and PC-12 cells. The effects of these two ginsenosides on neuronal differentiation are also examined.</p> <p>Methods</p> <p>LDH assay was used to measure cell viability after exposure to 6-OHDA and ginsenosides. Neuronal differentiation was evaluated by changes in cell morphology and density of neurite outgrowths. Western blotting was used to determine the ginsenosides' effects on activation of extracellular signal-regulated protein kinases (ERKs).</p> <p>Results</p> <p>Rh₁and Rg₂attenuated 6-OHDA toxicity in SH-SY5Y cells and induced neurite outgrowths in PC-12 cells. 6-OHDA-induced ERK phosphorylation was decreased by Rh₁and Rg₂. 20(R)-form and 20(S)-form of the ginsenosides exerted similar effects in inducing neurite outgrowths in PC-12 cells.</p> <p>Conclusion</p> <p>The present study demonstrates neuroprotective effects of ginsenosides Rh₁and Rg₂on neuronal cell lines. These results suggest potential Chinese medicine treatment for neurodegenerative disorders (<it>eg </it>Parkinson's disease).</p

Effects of a Structured Exercise Programme on Functional Balance in Visually Impaired Elderly Living in a Residential Setting

AbstractOne major priority for health care professionals is to minimize the risk of fall in the elderly population. While the quality of life of an individual is affected by fall accidents, management of post-fall disability in the elderly could be a huge economic burden to the society. Visually impaired elderly are at a higher risk of fall, because “vision”, an important component contributing to balance, is disturbed. The aim of this study was to examine the effects of an exercise programme, which focused on improvement of the functional balance of visually impaired elderly. Visually impaired elderly residents were randomly assigned to either the exercise training or control group. A multidimensional, individually tailored exercise programme was introduced by physiotherapists to the exercise group for 12 weeks. Functional balance status reflected by the Berg Balance Scale, chair stand test, and timed up-and-go test assessed before and after the 12-week training programme was compared between the two groups. Results demonstrated a significant improvement in balance outcomes in the exercise group (p < 0.05) but not in the control group. The results of this study suggest that a physiotherapist-designed strengthening and balance-training programme can improve the functional balance status of visually impaired elderly

Auricular acupuncture treatment for insomnia: A systematic review

Objectives: To review trials on the efficacy and safety of auricular acupuncture (AA) treatment for insomnia and to identify the most commonly used auricular acupoints for treating insomnia in the studies via a frequency analysis. Data sources: The international electronic databases searched included: (1) AMED; (2) the Cochrane library; (3) CINAHL; (4) EMBASE; and (5) MEDLINE.® Chinese electronic databases searched included: (1) VIP Information; (2) CBMdisc; and (3) CNKI. Study selection: Any randomized controlled trials using AA as an intervention without using any co-interventions for insomnia were included. Studies using AA versus no treatment, placebo, sham AA, or Western medicine were included. Data extraction: Two (2) independent reviewers were responsible for data extraction and assessment. The efficacy of AA was estimated by the relative risk (RR) using a meta-analysis. Results: Eight hundred and seventy eight (878) papers were searched. Six (6) trials (402 treated with AA among 673 participants) that met the inclusion criteria were retrieved. A meta-analysis showed that AA was chosen with a higher priority among the treatment subjects than among the controls (p < 0.05). The recovery and improvement rates produced by AA was significantly higher than those of diazepam (p < 0.05). The rate of success was higher when AA was used for enhancement of sleeping hours up to 6 hours in treatment subjects (p < 0.05). The efficacy of using Semen vaccariae ear seeds was better than that of the controls (p < 0.01); while magnetic pearls did not show statistical significance (p = 0.28). Six (6) commonly used auricular acupoints were Shenmen (100%), Heart (83.33%), Occiput (66.67%), Subcortex (50%), Brain and Kidney (each 33.33%, respectively). Conclusions: AA appears to be effective for treating insomnia. Because the trials were low quality, further clinical trials with higher design quality, longer duration of treatment, and longer follow-up should be conducted. © Mary Ann Liebert, Inc.published_or_final_versio