Evaluation of post-stroke spasticity from the subacute to chronic stages: A clinical and neurophysiologic study of motoneuron pool excitability.

Spasticity measured using clinical scales, such as the modified Ashworth scale (MAS), may not sufficiently evaluate the effectiveness of therapeutic interventions and predict prognosis. This study aimed to compare changes in H-reflex excitability in the spastic and unimpaired upper and lower limbs of patients with acute and chronic stroke. We also investigated the relationship between the degree of spasticity as assessed by the MAS and motor neuron pool excitability with by analyzing H-reflex excitability. Sixty adult patients with a first-ever stroke were recruited for this study. MAS scores were recorded in the post-stroke upper and lower limb muscles. H-reflexes and M-responses of the bilateral flexor carpi radialis and soleus were tested by stimulating the median and tibial nerves. The results showed that both the ratio of the maximal size of the H-reflex (Hmax) to the maximal size of the M-response (Mmax) and the ratio of the developmental slope of H-reflex (Hslp) to that of the M-responses (Mslp) were significantly higher on the spastic side than on the unimpaired side for the upper and lower limbs. In contrast, the ratio of the threshold of the H-reflex (Hth) to the threshold of the M-response (Mth) only showed significant differences between the two sides in the upper limbs. The Hslp/Mslp paretic/non-paretic ratio was increased in patients with MAS scores of 2 or 3 compared to MAS scores of 1 for both the upper and lower limbs, whereas the Hmax/Mmax paretic/non-paretic ratio showed significant differences between MAS scores of 2 or 3 and 1 only in the upper limbs. Moreover, in either the spastic or unimpaired sides, there were no significant differences in any of the three motoneuron pool excitability parameters, Hmax/Mmax, Hslp/Mslp, and Hth/Mth, between the shorter chronicity (time post-stroke ≤6 months) and longer chronicity groups (time post-stroke >6 months) for both the upper and lower limbs. These results suggest that Hslp/Mslp could be a potential neurophysiological indicator for evaluating the degree of spasticity in both the upper and lower limbs of patients with hemiplegia. The MAS and Hslp/Mslp characterize clinical and neurophysiologic spasticity, respectively, and could be used as an integrated approach to evaluate and follow up post-stroke spasticity.

3D-Printed Column with Porous Monolithic Packing for Online Solid-Phase Extraction of Multiple Trace Metals in Environmental Water Samples.

In this study, we used a multimaterial three-dimensional printing (3DP) technology and porous composite filaments (Lay-Fomm, Gel-Lay, and Lay-Felt) to fabricate solid phase extraction (SPE) columns for the enhanced extraction of multiple metal ions. When employed as sample pretreatment devices in an automatic flow injection analysis/inductively coupled plasma mass spectrometry (ICP-MS) system, these 3D-printed SPE columns performed the near-complete extractions of Mn, Co, Ni, Cu, Zn, Cd, and Pb ions from natural water samples prior to ICP-MS determination. After optimizing the column fabrication, the extraction conditions, and the automatic analysis system, the column packed with the porous composite Lay-Fomm 40 was found to provide the highest extraction performance-the extraction efficiencies of the listed metal ions were all greater than 99.2%, and the detection limits of the method ranged from 0.3 to 6.7 ng L-1. The detection of these metal ions in several reference materials (CASS-4, SLEW-3, 1640a, and 1643f) validated the reliability of this method; spike analyses of collected water samples (groundwater, river water, and seawater) demonstrated the applicability of the method. The nature of the printing materials enhanced the analytical performance of 3D-printed sample pretreatment devices. Such approaches will be useful to diversify the range of sample preparation schemes and analytical methods enabled by 3DP technologies.

Biodistribution of Graphene Oxide Determined through Postadministration Labeling with DNA-Conjugated Gold Nanoparticles and ICPMS.

Recent research has revealed the use of graphene oxide (GO) and its derivatives as a potential biomaterial because of their attractive physicochemical characteristics and functional properties. However, if GO and related derivatives are to become useful materials for biomedical applications, it will be necessary to evaluate their biodistribution for health and safety considerations. To obtain a more accurate biodistribution for GO, we (i) developed a postadministration labeling strategy employing DNA-conjugated gold nanoparticles (DNA-AuNPs) to selectively label administered GO in Solvable-treated tissue samples and (ii) constructed an automatic sample pretreatment scheme (using a C18-packed minicolumn) to effectively separate the DNA-AuNP-labeled GO from the unbound DNA-AuNPs and the dissolved tissue matrices, thereby enabling ultrasensitive, interference-free quantification of GO through measurement (inductively coupled plasma mass spectrometry) of the Au signal intensities. The DNA-AuNPs can bind to GO in a concentration- and time-dependent manner. After optimizing the labeling conditions (DNA length, incubation pH, DNA-AuNP concentration, and incubation time) and the separation scheme (sample loading flow rate, rinsing volume, and eluent composition), we found that A20R20-AuNPs (R20: random DNA sequence including A, T, C, and G) had the strongest binding affinity for labeling of the administered GO (dissociation constant: 36.0 fM) and that the method's detection limit reached 9.3 ag L-1 with a calibration curve having a working range from 10-1 to 1010 fg L-1. Moreover, this approach revealed that the intravenously administered GO accumulated predominantly in the liver and spleen at 1 and 12 h post administration, with apparent discrepancies in the concentrations measured using pre- and postadministration labeling strategies.

Portal vein innervation underlying the pressor effect of water ingestion with and without cold stress.

Water-induced pressor response appears mediated through the activation of transient receptor potential channel TRPV4 on hepatic portal circulation in animals. We sought to elucidate the mechanism of portal vein signaling in this response. Forty-five rats were divided into four groups: control rats without water ingestion (WI), control rats with WI, portal vein denervation rats with WI (PVDWI), and TRPV4 antagonist-treated rats with WI (anti-TRPV4WI). Cardiovascular responses were monitored throughout the experiments. Data analysis was performed using descriptive methods and spectral and cross-spectral analysis of blood pressure variability (BPV) and heart rate variability (HRV). Key results showed that at baseline (PreCS) before cold stress trial (CS), WI elicited robust pressor and tachycardia responses accompanied by spectral power changes, in particular, increases of low-frequency BPV (LFBPV) and very-LFBPV (VLFBPV), but decrease of very-low-frequency HRV. PVDWI, likewise, elicited pressor and tachycardia responses accompanied by increases of high-frequency BPV, high-frequency HRV, LFBPV, low-frequency HRV, and VLFBPV. When compared with WI at PreCS, WI at CS elicited pressor and tachycardia responses accompanied by increases of high-frequency BPV, LFBPV, and VLFBPV, whereas in WI, the CS-evoked pressor response and the accompanied LFBPV and VLFBPV increases were all tended augmented by PVDWI. When compared with WI and PVDWI at both PreCS and CS, however, anti-TRPV4WI attenuated their pressor responses and attenuated their increased LFBPV, VLFBPV, and very-low-frequency HRV. The results indicate that the portal vein innervation is critical for a buffering mechanism in splanchnic sympathetic activation and water-induced pressor response.

The Association between Migraine and Abdominal Aortic Aneurysms: A Nationwide Population-Based Cohort Study.

Previous studies have indicated that patients with migraine have a higher prevalence of risk factors known to be associated with cardiovascular diseases. There are also shared epidemiology and molecular mechanisms between migraine and abdominal aortic aneurysm (AAA). We hypothesized that patients with migraine could have an increased risk of AAA. To test this hypothesis, we used the National Health Insurance Research Database (NHIRD) to evaluate whether associations exist between migraine and AAA. The data for this nationwide population-based retrospective cohort study were obtained from the NHIRD in Taiwan. The assessed study outcome was the cumulative incidence of AAA in patients with migraine during a 15-year follow-up period. Among the 1,936,512 patients from the NHIRD, 53,668 (2.77%) patients were identified as having been diagnosed with migraine. The patients with migraine had a significantly higher cumulative risk of 3.558 of developing an AAA 5 years after the index date compared with the patients without migraine. At the end of the 15-year follow-up period, a significantly higher incidence of AAA (0.98%) was observed in the patients with migraine than in those without migraine (0.24%). We revealed an association between the development of migraine and AAA.

Effects of acrolein on the production of corticosterone in male rats.

Acrolein, an α, ß-unsaturated aldehyde, exists in a wide range of sources. Acrolein can be not only generated from all types of smoke but also produced endogenously from the metabolism by lipid peroxidation. The cellular influence of acrolein is due to its electrophilic character via binding to and depleting cellular nucleophiles. Although the toxicity of acrolein has been extensively studied, there is relatively little information about its impact on hormone release. This study aimed at the effect of acrolein on hypothalamic-pituitary-adrenal (H-P-A) axis. In an in vivo study, male rats were administrated with acrolein for 1 or 3days. The plasma corticosterone in response to a single injection of adrenocorticotropic hormone (ACTH) increased slowly in acrolein-pretreated rats than in control rats. Further investigating the steroidogenic pathway, the protein expressions of steroidogenic acute regulatory protein (StAR) and the upper receptor-melanocortin 2 receptor (MC2R) were attenuated in acrolein-treated groups. Another experiment using trilostane showed less activity of P450scc in zona fasciculata-reticularis (ZFR) cells in acrolein-treated groups. In addition to the suppressed ability of corticosterone production in ZFR cells, acrolein even had extended influence at higher concentrations. The lower ACTH was observed in the plasma from acrolein-pretreated rats. In an in vitro study, ZFR cells were incubated with acrolein and the results showed that corticosterone concentrations in media were decreased in a dose-dependent manner. Acrolein also desensitized the response of the ZFR cells to ACTH. These results suggested that acrolein decreased the releasing ability of corticosterone via an inhibition on the response of ZFR cells to ACTH and the reduction of protein expressions of StAR and MC2R as well as the activity of P450scc in rat ZFR cells. The present evidences showed that the H-P-A axis was affected by the administration of acrolein.