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Glycolysis is an ancient, widespread, and highly conserved metabolic pathway that converts glucose into pyruvate. In the canonical pathway, the phosphofructokinase (PFK) reaction plays an important role in controlling flux through the pathway. Clostridium thermocellum has an atypical glycolysis and uses pyrophosphate (PP(i)) instead of ATP as the phosphate donor for the PFK reaction. The reduced thermodynamic driving force of the PP(i)-PFK reaction shifts the entire pathway closer to thermodynamic equilibrium, which has been predicted to limit product titers. Here, we replace the PP(i)-PFK reaction with an ATP-PFK reaction. We demonstrate that the local changes are consistent with thermodynamic predictions: the ratio of fructose 1,6-bisphosphate to fructose-6-phosphate increases, and the reverse flux through the reaction (determined by (13)C labeling) decreases. The final titer and distribution of fermentation products, however, do not change, demonstrating that the thermodynamic constraints of the PP(i)-PFK reaction are not the sole factor limiting product titer. IMPORTANCE The ability to control the distribution of thermodynamic driving force throughout a metabolic pathway is likely to be an important tool for metabolic engineering. The phosphofructokinase reaction is a key enzyme in Embden-Mayerhof-Parnas glycolysis and therefore improving the thermodynamic driving force of this reaction in C. thermocellum is believed to enable higher product titers. Here, we demonstrate switching from pyrophosphate to ATP does in fact increases the thermodynamic driving force of the phosphofructokinase reaction in vivo. This study also identifies and overcomes a physiological hurdle toward expressing an ATP-dependent phosphofructokinase in an organism that utilizes an atypical glycolytic pathway. As such, the method described here to enable expression of ATP-dependent phosphofructokinase in an organism with an atypical glycolytic pathway will be informative toward engineering the glycolytic pathways of other industrial organism candidates with atypical glycolytic pathways.

The ability to control the distribution of thermodynamic driving force throughout a metabolic pathway is likely to be an important tool for metabolic engineering. The phosphofructokinase reaction is a key enzyme in Embden-Mayerhof-Parnas glycolysis and therefore improving the thermodynamic driving force of this reaction in C. thermocellum is believed to enable higher product titers.

Background High-intensity occupational therapy can improve arm function after stroke, but many people lack access to such therapy. Home-based therapies could address this need, but they don't typically address abnormal muscle co-activation, an important aspect of arm impairment. An earlier study using lab-based, myoelectric computer interface game training enabled chronic stroke survivors to reduce abnormal co-activation and improve arm function. Here, we assess feasibility of doing this training at home using a novel, wearable, myoelectric interface for neurorehabilitation training (MINT) paradigm. Objective Assess tolerability and feasibility of home-based, high-dose MINT therapy in severely impaired chronic stroke survivors. Methods Twenty-three participants were instructed to train with the MINT and game for 90 min/day, 36 days over 6 weeks. We assessed feasibility using amount of time trained and game performance. We assessed tolerability (enjoyment and effort) using a customized version of the Intrinsic Motivation Inventory at the conclusion of training. Results Participants displayed high adherence to near-daily therapy at home (mean of 82 min/day of training; 96% trained at least 60 min/day) and enjoyed the therapy. Training performance improved and co-activation decreased with training. Although a substantial number of participants stopped training, most dropouts were due to reasons unrelated to the training paradigm itself. Interpretation Home-based therapy with MINT is feasible and tolerable in severely impaired stroke survivors. This affordable, enjoyable, and mobile health paradigm has potential to improve recovery from stroke in a variety of settings. Clinicaltrials.gov: NCT03401762.

Over half of patients with elevated blood pressure require multi-drug treatment to achieve blood pressure control. However, multi-drug treatment may lead to lower adherence and more adverse drug effects compared with monotherapy.The Quadruple Ultra-low-dose Treatment for Hypertension (QUARTET) USA trial was designed to evaluate whether initiating treatment with ultra-low-dose quadruple-combination therapy will lower office blood pressure more effectively, and with fewer side effects, compared with initiating standard dose monotherapy in treatment naive patients with SBP180 and DBP110 mm Hg and patients on monotherapy with SBP160 and DBP100 mm Hg.QUARTET USA was a prospective, randomized, double-blind trial (ClinicalTrials.gov NCT03640312) conducted in federally qualified health centers in a large city in the US. Patients were randomly assigned (1:1) to either ultra-low-dose quadruple combination therapy or standard dose monotherapy. The primary outcome was mean change from baseline in office systolic blood pressure at 12-weeks, adjusted for baseline values. Secondary outcomes included measures of blood pressure change and variability, medication adherence, and health related quality of life. Safety outcomes included occurrence of serious adverse events, relevant adverse drug effects, and electrolyte abnormalities. A process evaluation aimed to understand provider experiences of implementation and participant experiences around side effects, adherence, and trust with clinical care.QUARTET USA was designed to evaluate whether a novel approach to blood pressure control would lower office blood pressure more effectively, and with fewer side effects, compared with standard dose monotherapy. QUARTET USA was conducted within a network of federally qualified healthcare centers with the aim of generating information on the safety and efficacy of ultra-low-dose quadruple-combination therapy in diverse groups that experience a high burden of hypertension.

Growing evidence suggests that environmentally relevant elevations in CO2 (

Background. Abnormal muscle co-activation contributes to impairment after stroke. We developed a myoelectric computer interface (MyoCI) training paradigm to reduce abnormal co-activation. MyoCI provides intuitive feedback about muscle activation patterns, enabling decoupling of these muscles. Objective. To investigate tolerability and effects of MyoCI training of 3 muscle pairs on arm motor recovery after stroke, including effects of training dose and isometric versus movement-based training. Methods. We randomized chronic stroke survivors with moderate-to-severe arm impairment to 3 groups. Two groups tested different doses of isometric MyoCI (60 vs 90 minutes), and one group tested MyoCI without arm restraint (90 minutes), over 6 weeks. Primary outcome was arm impairment (Fugl-Meyer Assessment). Secondary outcomes included function, spasticity, and elbow range-of-motion at weeks 6 and 10. Results. Over all 32 subjects, MyoCI training of 3 muscle pairs significantly reduced impairment (Fugl-Meyer Assessment) by 3.3 ± 0.6 and 3.1 ± 0.7 ( P < 10−4) at weeks 6 and 10, respectively. Each group improved significantly from baseline; no significant differences were seen between groups. Participants’ lab-based and home-based function also improved at weeks 6 and 10 ( P ≤ .01). Spasticity also decreased over all subjects, and elbow range-of-motion improved. Both moderately and severely impaired patients showed significant improvement. No participants had training-related adverse events. MyoCI reduced abnormal co-activation, which appeared to transfer to reaching in the movement group. Conclusions. MyoCI is a well-tolerated, novel rehabilitation tool that enables stroke survivors to reduce abnormal co-activation. It may reduce impairment and spasticity and improve arm function, even in severely impaired patients.

With the threat of coronavirus disease 2019 (Covid-19) enduring in the United States, effectively and equitably implementing testing, tracing, and self-isolation as key prevention and detection strategies remain critical to safely re-opening communities. As testing and tracing capacities increase, frameworks are needed to inform design and delivery to ensure their effective implementation and equitable distribution, and to strengthen community engagement in slowing and eventually stopping Covid-19 transmission. In this commentary, we highlight opportunities for integrating implementation research into planned and employed strategies in the United States to accelerate reach and effectiveness of interventions to more safely relax social distancing policies and open economies, schools, and other institutions. Implementation strategies, such as adapting evidence-based interventions based on contextual factors, promoting community engagement, and providing data audit and feedback on implementation outcomes, can support the translation of policies on testing, tracing, social distancing, and public mask use into reality. These data can demonstrate how interventions are put into practice and where adaptation in policy or practice is needed to respond to the needs of specific communities and socially vulnerable populations. Incorporating implementation research into Covid-19 policy design and translation into practice is urgently needed to mitigate the worsening health inequities in the pandemic toll and response. Applying rigorous implementation research frameworks and evaluation systems to the implementation of evidence-based interventions which are adapted to contextual factors can promote effective and equitable pandemic response and accelerate learning both among local stakeholders as well as between states to further inform their varied experiences and responses to the pandemic.

Background: During the COVID-19 pandemic, SARS-CoV-2 serology tests have been used to understand the extent to which populations have been infected. The objective of this study was to synthesize literature on SARS-CoV-2 seroprevalence studies, including sampling frames, study characteristics, assay test performance characteristics, and proportion of participants with IgG and IgM SARS-CoV-2 antibodies.Methods: Bibliometric databases, trial registers, pre-print servers, and grey literature were searched through May 27, 2020 using a published protocol to identify eligible studies. Title and abstract screening and full-text reviewing were performed in duplicate. Study-level data were extracted, and a narrative synthesis was performed. Results: Of the 4,049 studies screened for inclusion, 27 published reports were included, and 85 studies are ongoing. Most (52%) published reports were available through pre-print servers. Sample sizes ranged from 200 to 113,033 participants. Healthcare worker (n=9 studies, 33%) and non-representative, general population (n=10 studies, 37%) sampling frames were more commonly used than representative, general population sampling frames (n=7, 26%). Mean age ranged from 18 up to 69 years, and the proportion of females ranged from 25% to 85%. Test performance characteristics varied, including IgG sensitivity (range: 63.3% to 100%) and IgG specificity (range: 97.0% to 100%). IgG seroprevalence estimates ranged from 0.5% to 21.0%, and IgM seroprevalence ranged from 1.1% to 18.9%.Conclusion: More high-quality SARS-CoV-2 seroprevalence studies using validated assays with larger sample sizes from representative and targeted sampling frames are needed to better understand the true burden of disease, differential spread of the virus, and infection fatality rate.

Introduction: Many stroke survivors are often left with persistent upper extremity motor impairment that affect their overall quality of life. This study aims to evaluate the efficacy of using non-invasive electroencephalographic (EEG) based brain-computer interface (BCI) therapy to facilitate distal upper extremity motor function. Data was acquired from 18 participants ((mean age = 60 years, F = 9, M = 9, 5 = sub-chronic (over 1 year from stroke onset), 13 = chronic (less than 1 year)). Behavioral outcomes were measured using the Modified Ashworth Scale (MAS), a Motor Activity Log (MAL), and the Stroke Impact Scale (SIS). We investigated whether severely-impaired, chronic stroke survivors could use BCI treatment to recover from stroke at a rate similar to that of severely-impaired, sub-chronic stroke survivors after BCI intervention. Methods: EEG data was acquired using BCI2000 software and 16 channel EEG cap with electrodes positioned according to the standard 10-20 system over the sensorimotor cortex at C3 & C4. Participants were cued to move either their left or right hand to control a cursor towards the right or left side of a monitor. Data acquired at baseline (no more than one week prior to BCI therapy) and post-therapy (no more than one week following BCI therapy) were used in this analyses. Results: No significant decrease in improvement in the chronic group compared to the sub-chronic group (0.95 confidence interval) was observed. The chronic group showed significant improvement in their affected arm in: MAS elbow flexion (p = 0.03746), MAS finger extension (p = 0.01896), MAL arm use (p = 0.02065), MAL how well they could use their arm (p = 0.02065), SIS perceived strength (p = 0.04105), and SIS arm use for daily life tasks (p = 0.01741). Conclusion: For chronic stroke survivors, BCI intervention for restoration of upper extremity motor function may promote recovery at a rate similar to that of sub-chronic survivors.

While most survivors have some spontaneous recovery after stroke, they reach a functional plateau and are left with persistent motor impairments. An emerging therapy, EEG-based Brain-Computer Interface (BCI), shows promise in promoting neural reorganization and facilitating additional motor recovery after stroke, however, the relationships between the neuroplastic changes and behavioral outcomes following this therapy are not fully understood. We examined changes in resting-state functional connectivity (rsFC) in the motor network and behavioral measures, including Stroke Impact Scale (SIS) and Action Research Arm Test (ARAT), over the course this therapy and investigated functional connectivity - behavior correlations. Twenty-six stroke patients with mild to severe upper extremity impairment completed EEG-based BCI therapy. Resting fMRI and anatomical scans were acquired on a GE 3T MRI Scanner before therapy, mid-, post- and one-month post-therapy, along with a neuropsychology battery. MRI scans of right hemisphere stroke patients were flipped to treat all subjects as left lesion hemisphere patients. We performed whole network, inter-hemispheric and intra-hemispheric seed region based connectivity analyses to study changes in rsFC over time and identify correlations between changes in rsFC and behavior over time. After therapy, a significant increase in network connectivity (p =0.000003) and intra-hemispheric connectivity (p = 0.047) from pre- to one-month post-therapy was observed. Additionally, inter-hemispheric connectivity increased and trended towards significance (p = 0.058). A significant positive correlation was observed between changes in network-level rsFC and SIS ADL (p = 0.005). Changes in intra-hemispheric rsFC correlated with ARAT for the affected arm (p = 0.001) and SIS Mobility (p = 0.003). The results suggest that EEG-based BCI therapy facilitates changes in rsFC in the motor network in stroke survivors, and these changes in connectivity are correlated with improvements in behavioral outcomes. This analysis provides a foundation for furthering our understanding of the potential of EEG-based BCI as a therapeutic modality for stroke rehabilitation to promote neurophysiological changes and motor recovery.

Background Clostridium thermocellum is a promising microorganism for conversion of cellulosic biomass to biofuel, without added enzymes; however, the low ethanol titer produced by strains developed thus far is an obstacle to industrial application. Results Here, we analyzed changes in the relative concentration of intracellular metabolites in response to gradual addition of ethanol to growing cultures. For C. thermocellum, we observed that ethanol tolerance, in experiments with gradual ethanol addition, was twofold higher than previously observed in response to a stepwise increase in the ethanol concentration, and appears to be due to a mechanism other than mutation. As ethanol concentrations increased, we found accumulation of metabolites upstream of the glyceraldehyde 3-phosphate dehydrogenase (GAPDH) reaction and depletion of metabolites downstream of that reaction. This pattern was not observed in the more ethanol-tolerant organism Thermoanaerobacterium saccharolyticum. We hypothesize that the Gapdh enzyme may have different properties in the two organisms. Our hypothesis is supported by enzyme assays showing greater sensitivity of the C. thermocellum enzyme to high levels of NADH, and by the increase in ethanol tolerance and production when the T. saccharolyticum gapdh was expressed in C. thermocellum. Conclusions We have demonstrated that a metabolic bottleneck occurs at the GAPDH reaction when the growth of C. thermocellum is inhibited by high levels of ethanol. We then showed that this bottleneck could be relieved by expression of the gapdh gene from T. saccharolyticum. This enzyme is a promising target for future metabolic engineering work. Electronic supplementary material The online version of this article (10.1186/s13068-017-0961-3) contains supplementary material, which is available to authorized users.

Introduction: This current study is part of a larger, on-going clinical trial (NCT02098265), which evaluates non-invasive electroencephalographic (EEG) based brain-computer interface(BCI) therapy for restoration of distal upper extremity motor function in stroke survivors. We acquired data for 8 participants (mean age= 64 years) presenting with varying levels of upper-extremity motor deficits and chronicity since stroke. EEG based BCI task-related performance outcomes were compared with distal extremity behavioral testing on the 9-Hole Peg Test - 9HPT) to illustrate the relationship of BCI training performance on behavioral performance. Methods: EEG data is acquired with BCI2000, a 16 channel recording system (g.LADYbird-g. GAMMAsys-g. USBamp, Guger Technologies, Graz, Austria) with electrodes positioned according to the standard 10-20 system over the sensorimotor cortex at C3 & C4. Participants performed a hand movement task; randomly cued to move either their affected or unaffected hand depending on the appearance of virtual target and cursor on the screen. 9HPT Data was selected from two BCI conditions: 1) BCI with visual stimulus only, and 2) BCI with visual stimulation plus functional electrical stimulation (FES) of the impaired arm, and tongue stimulation (TS) at four time-points: baseline (prior to BCI therapy), mid-point of BCI therapy, post-therapy, and one month post-therapy. Results: BCI visual plus stimulus for the unaffected side was found to best relate to 9HPT scores (p= 0.0928) with a trend to significance. BCI visual plus stimulus for the affected side was not shown to correlate with 9HPT scores (p= 0.2655). The results suggest that 9HPT scores better relate with average task accuracy when the TS and FES adjuvants are incorporated (BCI stimulus vs 9H PT unaffected p= 0.09284, BCI stimulus vs 9H PT affected p= 0.26553) compared to the BCI visual only task (BCI visual vs 9HPT unaffected p=0.2702, BCI visual vs 9HPT affected (p= 0.89276). Conclusion: Non-invasive EEG-based BCI therapy may be suitable for the restoration of distal upper extremity motor function but average task accuracy does not appear to be a valid indicator of motor improvement. This finding suggests that visual only BCI systems are inadequate for motor rehabilitation.