Non‐technical summary Muscle spasticity, due to an upper motoneuron lesion, often leads to muscle contractures that limit range of motion and cause increased muscle stiffness. However, the elements ...responsible for this muscle adaption are unknown. Here we show that muscle tissue is stiffer in contracture compared to age‐matched children, implicating the extracellular matrix (ECM). However, titin, the major load‐bearing protein within muscle fibres, is not altered in contracture, and individual fibre stiffness is unaltered. Increased ECM stiffness is even more functionally significant given our finding of long in vivo sarcomeres which leads to much larger in vivo forces in muscle contracture. These results may lead to novel therapeutics for treating spastic muscle contracture.
Cerebral palsy (CP) results from an upper motoneuron (UMN) lesion in the developing brain. Secondary to the UMN lesion, which causes spasticity, is a pathological response by muscle – namely, contracture. However, the elements within muscle that increase passive mechanical stiffness, and therefore result in contracture, are unknown. Using hamstring muscle biopsies from pediatric patients with CP (n= 33) and control (n= 19) patients we investigated passive mechanical properties at the protein, cellular, tissue and architectural levels to identify the elements responsible for contracture. Titin isoform, the major load‐bearing protein within muscle cells, was unaltered in CP. Correspondingly, the passive mechanics of individual muscle fibres were not altered. However, CP muscle bundles, which include fibres in their constituent ECM, were stiffer than control bundles. This corresponded to an increase in collagen content of CP muscles measured by hydroxyproline assay and observed using immunohistochemistry. In vivo sarcomere length of CP muscle measured during surgery was significantly longer than that predicted for control muscle. The combination of increased tissue stiffness and increased sarcomere length interact to increase stiffness greatly of the contracture tissue in vivo. These findings provide evidence that contracture formation is not the result of stiffening at the cellular level, but stiffening of the ECM with increased collagen and an increase of in vivo sarcomere length leading to higher passive stresses.
Summary
Phase lag entropy, an electro‐encephalography‐based hypnotic depth indicator, calculates diversity in temporal patterns of phase relationship. We compared the performance of phase lag entropy ...with the bispectral index™ in 30 patients scheduled for elective surgery. We initiated a target‐controlled infusion of propofol using the Schnider model, and assessed sedation levels using the Modified Observer's Assessment of Alertness/Sedation scale every 30 s with each stepwise increase in the effect‐site propofol concentration. Phase lag entropy and bispectral index values were recorded. The correlation coefficient and prediction probability between phase lag entropy or bispectral index and the sedation level or effect‐site propofol concentration were analysed. We calculated baseline variabilities of phase lag entropy and bispectral index. In addition, we applied a non‐linear mixed‐effects model to obtain the pharmacodynamic relationships among the effect‐site propofol concentration, phase lag entropy or bispectral index and sedation level. As sedation increased, phase lag entropy and bispectral index both decreased. The prediction probability values of phase lag entropy and bispectral index for sedation levels were 0.697 and 0.700 (p = 0.261) and for the effect‐site concentration of propofol were 0.646 and 0.630 (p = 0.091), respectively. Baseline variability in phase lag entropy and bispectral index was 3.3 and 5.7, respectively. The predicted propofol concentrations, using the Schnider pharmacokinetic model, producing a 50% probability of moderate and deep sedation were 1.96 and 3.01 μg.ml−1, respectively. Phase lag entropy was found to be useful as a hypnotic depth indicator in patients receiving propofol sedation.
► Toxicogenomic response of Hsp70 in the dinoflagellate Prorocentrum minimum. ► Putative PmHsp70 contained three signature patterns of the Hsp70 family. ► EC50s are 1.1mgL−1 copper and 1.5mgL−1 ...biophenol A in P. minimum. ► PmHsp70 was significantly upregulated by thermal, Cu, and BPA exposures. ► Demonstration of the Hsp70 response in the dinoflagellate to thermal and toxic stress.
The heat shock protein 70 (Hsp70) family is an important part of the cell’s machinery for protein folding, and helps to protect cells from environmental stress. Although Hsp70 functions have been discovered in various organisms, studies on dinoflagellate Hsps are limited, except for a few phylogenetic attempts. In this study, we sequenced the complete open reading frame of the dinoflagellate Prorocentrum minimum Hsp70 (PmHsp70), and characterized its molecular functions. The putative PmHsp70 protein contained 3 signature patterns of the Hsp70 family. Phylogenetic analysis revealed that PmHsp70 belonged to the dinoflagellate clade. Real-time (RT)-PCR analyses revealed that PmHsp70 was upregulated by thermal stress. Further, we examined the transcriptional response of PmHsp70 to copper (Cu) and bisphenol A (BPA) exposures. In toxicity assays, Cu and BPA exhibited EC50-72h values of 1.07±0.138mgL−1 and 1.51±0.110mgL−1, respectively, in P. minimum. Expression of PmHsp70 was significantly upregulated in response to Cu and BPA exposures (one-way ANOVA, P<0.05). PmHsp70 displayed different expression patterns in response to different concentrations of Cu and BPA. This study evaluated typical characteristics and, for the first time, toxicant-related functions of PmHsp70. The results suggest that Hsp70 genes may play a vital role in the environmental stress responses of dinoflagellates.
•Toxicogenomic responses of HSP70/90 in marine diatom Ditylum brightwellii.•DbHSP70/90 contained conserved HSP family motifs, but different C-terminus motifs.•DbHSP70/90 were differentially involved ...in defense responses to environmental stress.•Metal toxicity was specifically affected by the conjugated anion in metal compounds.•DbHSP70/90 were not induced by certain organic pollutants, including EDCs.
Environmental hazard assessments using diatoms have been well documented; however, their molecular toxicology has not been sufficiently studied. In this study, we characterized heat shock protein (HSP) 70/90 of the diatom Ditylum brightwellii (Db) and evaluated their transcriptional profiles in response to various environmental stresses (e.g., thermal shocks and metal and non-metal pollutants). Putative DbHSP70 (658aa, 71.7kDa) and DbHSP90 (707aa, 80.2kDa) proteins had conserved HSP family motifs but different C-terminus motifs, that is, “EEVD” in DbHSP70 and “MEEVD” in DbHSP90. Phylogenetic analyses of both proteins showed that D. brightwellii was well clustered with other diatoms. Real-time PCR analysis showed that thermal stress considerably upregulated DbHSP70 and DbHSP90. As for chemical pollutants, DbHSP70 greatly responded to CuSO4 and NiSO4 exposure, but not CuCl2 or NiCl2. However, DbHSP90 was significantly upregulated by all the metal compounds tested (CuSO4, NiSO4, CuCl2, and NiCl2). Strikingly, the expression of both genes was not induced by the organic pollutants tested, such as endocrine-disrupting chemicals. These data suggest that DbHSP70 and DbHSP90 are differentially involved in the defense response against various environmental stressors. Moreover, metal toxicity may be specifically affected by the conjugated anion in the metal compounds (e.g., SO42- and Cl−).
Parkinson's disease (PD) is a progressive neurodegenerative disorder whose cardinal motor symptoms are attributed to dysfunction of basal ganglia circuits under conditions of low dopamine. Despite ...well-established physiological criteria to define basal ganglia dysfunction, correlations between individual parameters and motor symptoms are often weak, challenging their predictive validity and causal contributions to behavior. One limitation is that basal ganglia pathophysiology is studied only at end-stages of depletion, leaving an impoverished understanding of when deficits emerge and how they evolve over the course of depletion. In this study, we use toxin- and neurodegeneration-induced mouse models of dopamine depletion to establish the physiological trajectory by which the substantia nigra reticulata (SNr) transitions from the healthy to the diseased state. We find that physiological progression in the SNr proceeds in discrete state transitions that are highly stereotyped across models and correlate well with the prodromal and symptomatic stages of behavior.
Excessive body fat and the related dysmetabolic diseases affect both developed and developing countries. The aim of this study was to investigate the beneficial role of a bacterial culture ...supernatant (hereafter: BS) of
and
and their potential mechanisms of action on white-fat browning and lipolysis. For selection of four candidates among 55 Lactic acid producing bacteria (LAB) from human infant faeces, we evaluated by Oil Red O staining and
mRNA quantitation in 3T3-L1 preadipocytes. The expression of browning and lipolysis markers was examined along with
assays. The possible mechanism was revealed by molecular and biological experiments including inhibitor and small interfering RNA (siRNA) assays. In a mouse model, physiological, histological, and biochemical parameters and expression of some thermogenesis-related genes were compared among six experimental groups fed a high-fat diet and one normal-diet control group. The results allow us to speculate that BS treatment promotes browning and lipolysis both
and
. Moreover, the BS may activate thermogenic programs via a mechanism involving PKA-CREB signaling in 3T3-L1 cells. According to our data, we can propose that two LAB strains,
DS0956 and
DS0508, may be good candidates for a dietary supplement against obesity and metabolic diseases; however, further research is required for the development as dietary supplements or drugs.
Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) has been shown to have long-term clinical outcomes similar to those with open TLIF and decreased perioperative morbidity. This ...study assessed whether this procedure can be safely performed in outpatient settings. Ninety-six consecutive patients undergoing 1- or 2-level MIS-TLIFs were retrospectively reviewed. They were divided into inpatient and outpatient cohorts (36%). All had a minimum of 2 years of follow-up. Patient demographics, comorbidities, complications, and readmissions were examined. Early postoperative complications were stratified into wound related, infection, neurologic, implant related, and vascular injuries. Patients in the outpatient cohort were significantly younger, had lower American Society of Anesthesiologists physical status scores, and had lower Charlson Comorbidity Index scores than patients in the inpatient cohort. There were no statistically significant differences in overall postoperative complication rates, readmission rates, or final Oswestry Disability Index or visual analog scale scores between the 2 cohorts. The clinical outcomes of the outpatient TLIF procedure were similar to those of the inpatient procedure and it had an acceptable complication rate. Orthopedics. 2016; 39(6):e1218-e1222..
Herein, the ribonuclease H (RNase H) activity assay based on the target‐activated DNA polymerase activity is described. In this method, a detection probe composed of two functional sequences, a ...binding site for DNA polymerase and a catalytic substrate for RNase H, serves as a key component. The detection probe, at its initial state, suppresses the DNA polymerase activity, but it becomes destabilized by RNase H, which specifically hydrolyzes RNA in RNA/DNA hybrid duplexes. As a result, DNA polymerase recovers its activity and initiates multiple primer extension reactions in a separate TaqMan probe‐based signal transduction module, leading to a significantly enhanced fluorescence “turn‐on” signal. This assay can detect RNase H activity as low as 0.016 U mL−1 under optimized conditions. Furthermore, its potential use for evaluating RNase H inhibitors, which have been considered potential therapeutic agents against acquired immune deficiency syndrome (AIDS), is successfully explored. In summary, this approach is quite promising for the sensitive and accurate determination of enzyme activity and inhibitor screening.
A detection probe consisting of a DNA polymerase‐specific aptamer (DPA) and an RNA‐containing strand (RS) initially binds to and inhibits the DNA polymerase. But, in the presence of RNase H, the detection probe is destabilized by the degradation of its RNA part and it can no longer inhibit the DNA polymerase. As a consequence, the activated DNA polymerase initiates multiple cycles of primer extension reaction on TaqMan probe‐involved primer/template complexes, leading to a significant fluorescence enhancement.
High-frequency Deep Brain Stimulation (DBS) of the subcallosal cingulate (SCC) region is an emerging strategy for treatment-resistant depression (TRD). This study examined changes in SCC local field ...potentials (LFPs). The LFPs were recorded from the DBS leads following transient, unilateral stimulation at the neuroimaging-defined optimal electrode contact. The goal was identifying a putative electrophysiological measure of target engagement during implantation.
Fourteen consecutive patients underwent bilateral SCC DBS lead implantation. LFP recordings were collected from all electrodes during randomized testing of stimulation on each DBS contact (eight total). Analyses evaluated changes in spectral power before and after 3 min of unilateral stimulation at the contacts that later facilitated antidepressant response, as a potential biomarker of optimal contact selection in each hemisphere.
Lateralized and asymmetric power spectral density changes were detected in the SCC with acute unilateral SCC stimulation at those contacts subsequently selected for chronic, therapeutic stimulation. Left stimulation induced broadband ipsilateral decreases in theta, alpha, beta and gamma bands. Right stimulation effects were restricted to ipsilateral beta and gamma decreases. These asymmetric effects contrasted with identical white matter stimulation maps used in each hemisphere. More variable ipsilateral decreases were seen with stimulation at the adjacent "suboptimal" contacts, but changes were not statistically different from the "optimal" contact in either hemisphere despite obvious differences in impacted white matter bundles. Change in theta power was, however, most robust and specific with left-sided optimal stimulation, which suggested a putative functional biomarker on the left with no such specificity inferred on the right.
Hemisphere-specific oscillatory changes can be detected from the DBS lead with acute intraoperative testing at contacts that later engender antidepressant effects. Our approach defined potential target engagement signals for further investigation, particularly left-sided theta decreases following initial exposure to stimulation. More refined models combining tractography, bilateral SCC LFP, and cortical recordings may further improve the precision and specificity of these putative biomarkers. It may also optimize and standardize the lead implantation procedure and provide input signals for next generation closed-loop therapy and/or monitoring technologies for TRD.
PDF
