Modular Low-Copy-Number Plasmid Vectors for Rhodobacterales with Extended Host Range in Alphaproteobacteria.

Members of the alphaproteobacterial order Rhodobacterales are metabolically diverse and highly abundant in the ocean. They are becoming increasingly interesting for marine biotechnology, due to their ecological adaptability, wealth of versatile low-copy-number plasmids, and their ability to produce secondary metabolites. However, molecular tools for engineering strains of this bacterial lineage are limited. Here, we expand the genetic toolbox by establishing standardized, modular repABC-based plasmid vectors of four well-characterized compatibility groups from the Roseobacter group applicable in the Rhodobacterales, and likely in further alphaproteobacterial orders (Hyphomicrobiales, Rhodospirillales, Caulobacterales). We confirmed replication of these newly constructed pABC vectors in two members of Rhodobacterales, namely, Dinoroseobacter shibae DFL 12 and Rhodobacter capsulatus B10S, as well as in two members of the alphaproteobacterial order Hyphomicrobiales (synonym: Rhizobiales; Ensifer meliloti 2011 and "Agrobacterium fabrum" C58). Maintenance of the pABC vectors in the biotechnologically valuable orders Rhodobacterales and Hyphomicrobiales facilitates the shuttling of genetic constructs between alphaproteobacterial genera and orders. Additionally, plasmid replication was verified in one member of Rhodospirillales (Rhodospirillum rubrum S1) as well as in one member of Caulobacterales (Caulobacter vibrioides CB15N). The modular construction of pABC vectors and the usage of four compatible replication systems, which allows their coexistence in a host cell, are advantageous features for future implementations of newly designed synthetic pathways. The vector applicability was demonstrated by functional complementation of a nitrogenase mutant phenotype by two complementary pABC-based plasmids in R. capsulatus.

Experimental evidence for Parthanatos-like mode of cell death of heat-damaged human skin fibroblasts in a cell culture-based in vitro burn model.

The cellular mechanisms of burn conversion of heat damaged tissue are center of many studies. Even if the molecular mechanisms of heat-induced cell death are controversially discussed in the current literature, it is widely accepted that caspase-mediated apoptosis plays a central role. In the current study we wanted to develop further information on the nature of the mechanism of heat-induced cell death of fibroblasts in vitro. We found that heating of human fibroblast cultures (a 10 s rise from 37 °C to 67 °C followed by a 13 s cool down to 37 °C) resulted in the death of about 50% of the cells. However, the increase in cell death started with a delay, about one hour after exposure to heat, and reached the maximum after about five hours. The lack of clear evidence for an active involvement of effector caspase in the observed cell death mechanism and the lack of observation of the occurrence of hypodiploid nuclei contradict heat-induced cell death by caspase-mediated apoptosis. Moreover, a dominant heat-induced increase in PARP1 protein expression, which correlated with a time-delayed ATP synthesis inhibition, appearance of double-strand breaks and secondary necrosis, indicate a different type of cell death than apoptosis. Indeed, increased translocation of Apoptosis Inducing Factor (AIF) and Macrophage Migration Inhibitory Factor (MIF) into cell nuclei, which correlates with the mentioned enhanced PARP1 protein expression, indicate PARP1-induced, AIF-mediated and MIF-activated cell death. With regard to the molecular actors involved, the cellular processes and temporal sequences, the mode of cell death observed in our model is very similar to the cell death mechanism via Parthanatos described in the literature.

Highly efficient and widely tunable Si3N4 waveguide-based optical parametric oscillator.

We demonstrate an efficient and widely tunable synchronously pumped optical parametric oscillator (OPO) exploiting four-wave mixing (FWM) in a silicon nitride (Si3N4) waveguide with inverted tapers. At a pump pulse duration of 2 ps, the waveguide-based OPO (WOPO) exhibited a high external pump-to-idler conversion efficiency of up to -7.64 dB at 74% pump depletion and a generation of up to 387 pJ output idler pulse energy around 1.13 µm wavelength. Additionally, the parametric oscillation resulted in a 64 dB amplification of idler power spectral density in comparison to spontaneous FWM, allowing for a wide idler wavelength tunability of 191 nm around 1.15 µm. Our WOPO represents a significant improvement of conversion efficiency as well as output energy among χ3 WOPOs, rendering an important step towards a highly efficient and widely tunable chip-based light source for, e.g., coherent anti-Stokes Raman scattering.

Noninvasive Electromagnetic Phrenic Nerve Stimulation in Critically Ill Patients: A Feasibility Study.

BACKGROUND: Electromagnetic stimulation of the phrenic nerve induces diaphragm contractions, but no coils for clinical use have been available. We recently demonstrated the feasibility of ventilation using bilateral transcutaneous noninvasive electromagnetic phrenic nerve stimulation (NEPNS) before surgery in lung-healthy patients with healthy weight in a dose-dependent manner. RESEARCH QUESTION: Is NEPNS feasible in critically ill patients in an ICU setting? STUDY DESIGN AND METHODS: This feasibility nonrandomized controlled study aimed to enroll patients within 36 h of intubation who were expected to remain ventilated for ≥ 72 h. The intervention group received 15-min bilateral transcutaneous NEPNS bid, whereas the control group received standard care. If sufficient, NEPNS was used without pressure support to ventilate the patient; pressure support was added if necessary to ventilate the patient adequately. The primary outcome was feasibility, measured as time to find the optimal stimulation position. Further end points were sessions performed according to the protocol or allowing a next-day catch-up session and tidal volume achieved with stimulation reaching only 3 to 6 mL/kg ideal body weight (IBW). A secondary end point was expiratory diaphragm thickness measured with ultrasound from days 1 to 10 (or extubation). RESULTS: The revised European Union regulation mandated reapproval of medical devices, prematurely halting the study. Eleven patients (five in the intervention group, six in the control group) were enrolled. The median time to find an adequate stimulation position was 23 s (interquartile range, 12-62 s). The intervention bid was executed in 87% of patients, and 92% of patients including a next-day catch-up session. Ventilation with 3 to 6 mL/kg IBW was achieved in 732 of 1,701 stimulations (43.0%) with stimulation only and in 2,511 of 4,036 stimulations (62.2%) with additional pressure support. A decrease in diaphragm thickness was prevented by bilateral NEPNS (P = .034) until day 10. INTERPRETATION: Bilateral transcutaneous NEPNS was feasible in the ICU setting with the potential benefit of preventing diaphragm atrophy during mechanical ventilation. NEPNS ventilation effectiveness needs further assessment. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT05238753; URL: www. CLINICALTRIALS: gov.

Automated characterization of patient-ventilator interaction using surface electromyography.

BACKGROUND: Characterizing patient-ventilator interaction in critically ill patients is time-consuming and requires trained staff to evaluate the behavior of the ventilated patient. METHODS: In this study, we recorded surface electromyography ([Formula: see text]) signals from the diaphragm and intercostal muscles and esophageal pressure ([Formula: see text]) in mechanically ventilated patients with ARDS. The sEMG recordings were preprocessed, and two different algorithms (triangle algorithm and adaptive thresholding algorithm) were used to automatically detect inspiratory patient effort. Based on the detected inspirations, major asynchronies (ineffective, auto-, and double triggers and double efforts), delayed and synchronous triggers were computationally classified. Reverse triggers were not considered in this study. Subsequently, asynchrony indices were calculated. For the validation of detected efforts, two experts manually annotated inspiratory patient activity in [Formula: see text], blinded toward each other, the [Formula: see text] signals, and the algorithmic results. We also classified patient-ventilator interaction and calculated asynchrony indices with manually detected inspirations in [Formula: see text] as a reference for automated asynchrony classification and asynchrony index calculation. RESULTS: Spontaneous breathing activity was recognized in 22 out of the 36 patients included in the study. Evaluation of the accuracy of the algorithms using 3057 inspiratory efforts in [Formula: see text] demonstrated reliable detection performance for both methods. Across all datasets, we found a high sensitivity (triangle algorithm/adaptive thresholding algorithm: 0.93/0.97) and a high positive predictive value (0.94/0.89) against expert annotations in [Formula: see text]. The average delay of automatically detected inspiratory onset to the [Formula: see text] reference was [Formula: see text]79 ms/29 ms for the two algorithms. Our findings also indicate that automatic asynchrony index prediction is reliable. For both algorithms, we found the same deviation of [Formula: see text] to the [Formula: see text]-based reference. CONCLUSIONS: Our study demonstrates the feasibility of automating the quantification of patient-ventilator asynchrony in critically ill patients using noninvasive sEMG. This may facilitate more frequent diagnosis of asynchrony and support improving patient-ventilator interaction.

Viral load of SARS-CoV-2 in surgical smoke in minimally invasive and open surgery: a single-center prospective clinical trial.

At the beginning of the COVID-19 pandemic, it was assumed that SARS-CoV-2 could be transmitted through surgical smoke generated by electrocauterization. Minimally invasive surgery (MIS) was targeted due to potentially higher concentrations of the SARS-CoV-2 particles in the pneumoperitoneum. Some surgical societies even recommended open surgery instead of MIS to prevent the potential spread of SARS-CoV-2 from the pneumoperitoneum. This study aimed to detect SARS-CoV-2 in surgical smoke during open and MIS. Patients with SARS-CoV-2 infection who underwent open surgery or MIS at Heidelberg University Hospital were included in the study. A control group of patients without SARS-CoV-2 infection undergoing MIS or open surgery was included for comparison. The trial was approved by the Ethics Committee of Heidelberg University Medical School (S-098/2021). The following samples were collected: nasopharyngeal and intraabdominal swabs, blood, urine, surgical smoke, and air samples from the operating room. An SKC BioSampler was used to sample the surgical smoke from the pneumoperitoneum during MIS and the approximate surgical field during open surgery in 15 ml of sterilized phosphate-buffered saline. An RT-PCR test was performed on all collected samples to detect SARS-CoV-2 viral particles. Twelve patients with proven SARS-CoV-2 infection underwent open abdominal surgery. Two SARS-CoV-2-positive patients underwent an MIS procedure. The control group included 24 patients: 12 underwent open surgery and 12 MIS. One intraabdominal swab in a patient with SARS-CoV-2 infection was positive for SARS-CoV-2. However, during both open surgery and MIS, none of the surgical smoke samples showed any detectable viral particles of SARS-CoV-2. The air samples collected at the end of the surgical procedure showed no viral particles of SARS-CoV-2. Major complications (CD ≥ IIIa) were more often observed in SARS-CoV-2 positive patients (10 vs. 4, p = 0.001). This study showed no detectable viral particles of SARS-CoV-2 in surgical smoke sampled during MIS and open surgery. Thus, the discussed risk of transmission of SARS-CoV-2 via surgical smoke could not be confirmed in the present study.

Pangenome graph layout by Path-Guided Stochastic Gradient Descent.

Motivation: The increasing availability of complete genomes demands for models to study genomic variability within entire populations. Pangenome graphs capture the full genomic similarity and diversity between multiple genomes. In order to understand them, we need to see them. For visualization, we need a human readable graph layout: A graph embedding in low (e.g. two) dimensional depictions. Due to a pangenome graph's potential excessive size, this is a significant challenge. Results: In response, we introduce a novel graph layout algorithm: the Path-Guided Stochastic Gradient Descent (PG-SGD). PG-SGD uses the genomes, represented in the pangenome graph as paths, as an embedded positional system to sample genomic distances between pairs of nodes. This avoids the quadratic cost seen in previous versions of graph drawing by Stochastic Gradient Descent (SGD). We show that our implementation efficiently computes the low dimensional layouts of gigabase-scale pangenome graphs, unveiling their biological features. Availability: We integrated PG-SGD in ODGI which is released as free software under the MIT open source license. Source code is available at https://github.com/pangenome/odgi.

Toward integrated tantalum pentoxide optical parametric oscillators.

We present a hybrid waveguide-fiber optical parametric oscillator (OPO) exploiting degenerate four-wave mixing in tantalum pentoxide. The OPO, pumped with ultrashort pulses at 1.55 µm wavelength, generated tunable idler pulses with up to 4.1 pJ energy tunable center wavelength between 1.63 µm and 1.68 µm. An upper bound for the total tolerable cavity loss of 32 dB was found, rendering a chip-integrated OPO feasible as a compact and robust light source.

Scalable RT-LAMP-based SARS-CoV-2 testing for infection surveillance with applications in pandemic preparedness.

Throughout the SARS-CoV-2 pandemic, limited diagnostic capacities prevented sentinel testing, demonstrating the need for novel testing infrastructures. Here, we describe the setup of a cost-effective platform that can be employed in a high-throughput manner, which allows surveillance testing as an acute pandemic control and preparedness tool, exemplified by SARS-CoV-2 diagnostics in an academic environment. The strategy involves self-sampling based on gargling saline, pseudonymized sample handling, automated RNA extraction, and viral RNA detection using a semiquantitative multiplexed colorimetric reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay with an analytical sensitivity comparable with RT-qPCR. We provide standard operating procedures and an integrated software solution for all workflows, including sample logistics, analysis by colorimetry or sequencing, and communication of results. We evaluated factors affecting the viral load and the stability of gargling samples as well as the diagnostic sensitivity of the RT-LAMP assay. In parallel, we estimated the economic costs of setting up and running the test station. We performed > 35,000 tests, with an average turnover time of < 6 h from sample arrival to result announcement. Altogether, our work provides a blueprint for fast, sensitive, scalable, cost- and labor-efficient RT-LAMP diagnostics, which is independent of potentially limiting clinical diagnostics supply chains.

Quantitative Gas Exchange in Extracorporeal Membrane Oxygenation-A New Device: Accuracy, Approach-based Difficulties, and Caloric Targeting.

Measurement of oxygen uptake (VO 2 ) and carbon dioxide removal (VCO 2 ) on membrane lungs (MLs) during extracorporeal membrane oxygenation (ECMO) provides potential for improved and safer therapy. Real-time monitoring of ML function and degradation, calculating caloric needs as well as cardiac output, and weaning algorithms are among the future possibilities. Our study compared the continuous measurement of the standalone Quantum Diagnostics System (QDS) with the published Measuring Energy Expenditure in ECMO patients (MEEP) approach, which calculates sequential VO 2 and VCO 2 values via blood gas analysis and a physiologic gas content model. Thirty-nine datasets were acquired during routine venovenous ECMO intensive care treatment and analyzed. VO 2 was clinically relevant underestimated via the blood-sided measurement of the QDS compared to the MEEP approach (mean difference -42.61 ml/min, limits of agreement [LoA] -2.49/-87.74 ml), which could be explained by the missing dissolved oxygen fraction of the QDS equation. Analysis of VCO 2 showed scattered values with wide limits of agreement (mean difference 54.95 ml/min, LoA 231.26/-121.40 ml/min) partly explainable by a calculation error of the QDS. We described potential confounders of gas-sided measurements in general which need further investigation and recommendations for enhanced devices.

GFAP and NfL increase during neurotoxicity from high baseline levels in pediatric CD19-CAR T-cell patients.

There is a need for biomarkers to predict and measure the severity of immune effector cell-associated neurotoxicity syndrome (ICANS). Glial fibrillary acidic protein (GFAP) and neurofilament light chain (NfL) are well-validated biomarkers of astroglial and neuronal injury, respectively. We hypothesized that pretreatment GFAP and NfL levels can predict the risk of subsequent ICANS and that increases in GFAP and NfL levels during treatment reflect ICANS severity. We measured cerebrospinal fluid GFAP (cGFAP) and NfL (cNfL) along with serum NfL (sNfL) levels at pretreatment and day 7 to 10 after chimeric antigen receptor (CAR) T-cell infusion in 3 pediatric cohorts treated with CD19- or CD19/CD22-directed CAR T cells. cGFAP and cNfL levels increased during grade ≥1 ICANS in patients treated with CD19-directed CAR T cells but not in those who received CD19/CD22-directed CAR T cells. The sNfL levels did not increase during ICANS. Prelymphodepletion cGFAP, cNfL, and sNfL levels were not predictive of subsequent ICANS. Elevated baseline cGFAP levels were associated with a history of transplantation. Patients with prior central nervous system (CNS) radiation had higher cNfL levels, and elevated baseline sNfL levels were associated with a history of peripheral neuropathy. Thus, cGFAP and cNfL may be useful biomarkers for measuring the severity of CNS injury during ICANS in children. Elevated baseline levels of cGFAP, cNfL, and sNfL likely reflect the cumulative injury to the central and peripheral nervous systems from prior treatment. However, levels of any of the 3 biomarkers before CAR T-cell infusion did not predict the risk of ICANS.

Endovascular thrombectomy in young patients with stroke.

BACKGROUND: Endovascular treatment (ET) is standard of care in patients with acute ischemic stroke due to large vessel occlusion, but data on ET in young patients remain limited. AIM: We aim to compare outcomes for young stroke patients undergoing ET in a matched cohort. METHODS: We analyzed patients from an observational multicenter cohort with acute ischemic stroke and ET, the German Stroke Registry-Endovascular Treatment trial. Baseline characteristics, procedural parameters, and functional outcome at 90 days were compared between young (<50 years) and older (⩾50 years) patients with and without nearest-neighbor 1:1 propensity score matching. RESULTS: Out of 6628 acute ischemic stroke patients treated with ET, 363 (5.5%) were young. Young patients differed with regard to prognostic outcome characteristics. Specifically, National Institutes of Health Stroke Scale (NIHSS) at admission was lower (median 13, interquartile range (IQR) 8-17 vs. 15, IQR 9-19, p < 0.001), and prestroke dependence was less frequent (2.9% vs. 12.2%, p < 0.001) than in older patients. Compared to a matched cohort of older patients, ET was faster (time from groin puncture to flow restoration, 35 vs. 45 min, p < 0.001) and intracranial hemorrhage was less frequent in young patients (10.0% vs. 25.9%, p < 0.001). Good functional outcome (modified Rankin Scale (mRS) 0-2) at 3 months was achieved more frequently in young patients (71.6% vs. 44.1%, p < 0.001), and overall mortality was lower (6.7% vs. 25.4%, p < 0.001). Among previously employed young patients (n = 177), 37.9% returned to work at 3-month follow-up, while 74.1% of the remaining patients were still undergoing rehabilitation. CONCLUSION: Young stroke patients undergoing ET have better outcomes compared to older patients, even when matched for prestroke condition, comorbidities, and stroke severity. Hence, more liberal guidelines to perform ET for younger patients may have to be established by future studies.

Correction: Engelhardt et al. Sex-Specific Aspects of Skeletal Muscle Metabolism in the Clinical Context of Intensive Care Unit-Acquired Weakness. J. Clin. Med. 2022, 11, 846.

Due to an Editorial Office error during processing, a number of male and female symbols were incorrectly shown in the pdf version of the manuscript [...].

Antithrombotic treatment and outcome after endovascular treatment and acute carotid artery stenting in stroke patients with atrial fibrillation.

BACKGROUND: Oral anticoagulation (OAC) is the mainstay of secondary prevention in ischemic stroke patients with atrial fibrillation (AF). However, in AF patients with large vessel occlusion stroke treated by endovascular therapy (ET) and acute carotid artery stenting (CAS), the optimal antithrombotic medication remains unclear. METHODS: This is a subgroup analysis of the German Stroke Registry-Endovascular Treatment (GSR-ET), a prospective multicenter cohort of patients with large vessel occlusion stroke undergoing ET. Patients with AF and CAS during ET were included. We analyzed baseline and periprocedural characteristics, antithrombotic strategies and functional outcome at 90 days. RESULTS: Among 6635 patients in the registry, a total of 82 patients (1.2%, age 77.9 ± 8.0 years, 39% female) with AF and extracranial CAS during ET were included. Antithrombotic medication at admission, during ET, postprocedural and at discharge was highly variable and overall mortality in hospital (21%) and at 90 days (39%) was high. Among discharged patients (n = 65), most frequent antithrombotic regimes were dual antiplatelet therapy (DAPT, 37%), single APT + OAC (25%) and DAPT + OAC (20%). Comparing DAPT to single or dual APT + OAC, clinical characteristics at discharge were similar (median NIHSS 7.5 [interquartile range, 3-10.5] vs 7 [4-11], p = 0.73, mRS 4 [IQR 3-4] vs. 4 [IQR 3-5], p = 0.79), but 90-day mortality was higher without OAC (32 vs 4%, p = 0.02). CONCLUSIONS: In AF patients who underwent ET and CAS, 90-day mortality was higher in patients not receiving OAC. REGISTRATION: https://www. CLINICALTRIALS: gov ; Unique identifier: NCT03356392.

Muscular myostatin gene expression and plasma concentrations are decreased in critically ill patients.

BACKGROUND: The objective was to investigate the role of gene expression and plasma levels of the muscular protein myostatin in intensive care unit-acquired weakness (ICUAW). This was performed to evaluate a potential clinical and/or pathophysiological rationale of therapeutic myostatin inhibition. METHODS: A retrospective analysis from pooled data of two prospective studies to assess the dynamics of myostatin plasma concentrations (day 4, 8 and 14) and myostatin gene (MSTN) expression levels in skeletal muscle (day 15) was performed. Associations of myostatin to clinical and electrophysiological outcomes, muscular metabolism and muscular atrophy pathways were investigated. RESULTS: MSTN gene expression (median [IQR] fold change: 1.00 [0.68-1.54] vs. 0.26 [0.11-0.80]; p = 0.004) and myostatin plasma concentrations were significantly reduced in all critically ill patients when compared to healthy controls. In critically ill patients, myostatin plasma concentrations increased over time (median [IQR] fold change: day 4: 0.13 [0.08/0.21] vs. day 8: 0.23 [0.10/0.43] vs. day 14: 0.40 [0.26/0.61]; p < 0.001). Patients with ICUAW versus without ICUAW showed significantly lower MSTN gene expression levels (median [IQR] fold change: 0.17 [0.10/0.33] and 0.51 [0.20/0.86]; p = 0.047). Myostatin levels were directly correlated with muscle strength (correlation coefficient 0.339; p = 0.020) and insulin sensitivity index (correlation coefficient 0.357; p = 0.015). No association was observed between myostatin plasma concentrations as well as MSTN expression levels and levels of mobilization, electrophysiological variables, or markers of atrophy pathways. CONCLUSION: Muscular gene expression and systemic protein levels of myostatin are downregulated during critical illness. The previously proposed therapeutic inhibition of myostatin does therefore not seem to have a pathophysiological rationale to improve muscle quality in critically ill patients. TRIAL REGISTRATION: ISRCTN77569430 -13th of February 2008 and ISRCTN19392591 17th of February 2011.

Four Weeks of Intensified Training Enhances On-Ice Intermittent Exercise Performance and Increases Maximal Oxygen Consumption of Youth National-Team Ice Hockey Players.

PURPOSE: We investigated whether 4 weeks of intensified training consisting of speed endurance training (SET) enhanced high-intensity exercise performance in youth national-team ice hockey players. METHODS: Utilizing a randomized crossover design, we subjected 17 players to 4 weeks of SET, comprising 6 to 10 × 20 seconds at maximal effort (>95% maximum ice skating speed) with 120-second recovery performed 3 times weekly, or maintenance of regular training (control period). Before and after each period, players completed ice-hockey-specific tests on ice, including a Yo-Yo Intermittent Recovery Level 1 test, a 30-m sprint test, and an agility test. On a separate day, players were assessed for body composition with dual-energy X-ray absorptiometry and performed countermovement jump, maximal voluntary isometric knee extensor contraction, a 15-second maximal sprint test, and a submaximal and incremental test on a bike ergometer in which pulmonary oxygen consumption was determined. RESULTS: Yo-Yo Intermittent Recovery Level 1 test performance increased (P < .001) by 14% (95% CI, 201-496 m) during the SET period. Maximal pulmonary oxygen consumption (P < .05) and time to exhaustion (P < .05) were 4.8% and 6.5% higher, respectively, after the SET period than before. Fat-free mass increased (P < .01) during the SET period by 1.7 kg (95% CI, 1.0-2.5), whereas fat mass remained unchanged. These effects were superior to the control period. CONCLUSIONS: These findings underpin the effectiveness of SET for improving on-ice high-intensity performance and highlight that elite ice hockey players can benefit from implementing SET.

Blind source separation of inspiration and expiration in respiratory sEMG signals.

Objective.Surface electromyography (sEMG) is a noninvasive option for monitoring respiratory effort in ventilated patients. However, respiratory sEMG signals are affected by crosstalk and cardiac activity. This work addresses the blind source separation (BSS) of inspiratory and expiratory electrical activity in single- or two-channel recordings. The main contribution of the presented methodology is its applicability to the addressed muscles and the number of available channels.Approach.We propose a two-step procedure consisting of a single-channel cardiac artifact removal algorithm, followed by a single- or multi-channel BSS stage. First, cardiac components are removed in the wavelet domain. Subsequently, a nonnegative matrix factorization (NMF) algorithm is applied to the envelopes of the resulting wavelet bands. The NMF is initialized based on simultaneous standard pneumatic measurements of the ventilated patient.Main results.The proposed estimation scheme is applied to twelve clinical datasets and simulated sEMG signals of the respiratory system. The results on the clinical datasets are validated based on expert annotations using invasive pneumatic measurements. In the simulation, three measures evaluate the separation success: The distortion and the correlation to the known ground truth and the inspiratory-to-expiratory signal power ratio. We find an improvement across all SNRs, recruitment patterns, and channel configurations. Moreover, our results indicate that the initialization strategy replaces the manual matching of sources after the BSS.Significance.The proposed separation algorithm facilitates the interpretation of respiratory sEMG signals. In crosstalk affected measurements, the developed method may help clinicians distinguish between inspiratory effort and other muscle activities using only noninvasive measurements.

Sex-Specific Aspects of Skeletal Muscle Metabolism in the Clinical Context of Intensive Care Unit-Acquired Weakness.

(1) Background: Female sex is considered a risk factor for Intensive Care Unit-Acquired Weakness (ICUAW). The aim is to investigate sex-specific aspects of skeletal muscle metabolism in the context of ICUAW. (2) Methods: This is a sex-specific sub-analysis from two prospectively conducted trials examining skeletal muscle metabolism and advanced muscle activating measures in critical illness. Muscle strength was assessed by Medical Research Council Score. The insulin sensitivity index was analyzed by hyperinsulinemic-euglycemic (HE) clamp. Muscular metabolites were studied by microdialysis. M. vastus lateralis biopsies were taken. The molecular analysis included protein degradation pathways. Morphology was assessed by myocyte cross-sectional area (MCSA). Multivariable linear regression models for the effect of sex on outcome parameters were performed. (3) Results: n = 83 (♂n = 57, 68.7%; ♀n = 26, 31.3%) ICU patients were included. ICUAW was present in 81.1%♂ and in 82.4%♀ at first awakening (p = 0.911) and in 59.5%♂ and in 70.6%♀ at ICU discharge (p = 0.432). Insulin sensitivity index was reduced more in women than in men (p = 0.026). Sex was significantly associated with insulin sensitivity index and MCSA of Type IIa fibers in the adjusted regression models. (4) Conclusion: This hypothesis-generating analysis suggests that more pronounced impairments in insulin sensitivity and lower MCSA of Type IIa fibers in critically ill women may be relevant for sex differences in ICUAW.

Impact of protocol-based physiotherapy on insulin sensitivity and peripheral glucose metabolism in critically ill patients.

BACKGROUND: The impact of physiotherapy on insulin sensitivity and peripheral glucose metabolism in critically ill patients is not well understood. METHODS: This pooled analysis investigates the impact of different physiotherapeutic strategies on insulin sensitivity in critically ill patients. We pooled data from two previous trials in adult patients with sequential organ failure assessment score (SOFA)≥ 9 within 72 h of intensive care unit (ICU) admission, who received hyperinsulinaemic euglycaemic (HE) clamps. Patients were divided into three groups: standard physiotherapy (sPT, n = 22), protocol-based physiotherapy (pPT, n = 8), and pPT with added muscle activating measures (pPT+, n = 20). Insulin sensitivity index (ISI) was determined by HE clamp. Muscle metabolites lactate, pyruvate, and glycerol were measured in the M. vastus lateralis via microdialysis during the HE clamp. Histochemical visualization of glucose transporter-4 (GLUT4) translocation was performed in surgically extracted muscle biopsies. All data are reported as median (25th/75th percentile) (trial registry: ISRCTN77569430 and ISRCTN19392591/ethics approval: Charité-EA2/061/06 and Charité-EA2/041/10). RESULTS: Fifty critically ill patients (admission SOFA 13) showed markedly decreased ISIs on Day 17 (interquartile range) 0.029 (0.022/0.048) (mg/min/kg)/(mU/L) compared with healthy controls 0.103 (0.087/0.111), P < 0.001. ISI correlated with muscle strength measured by medical research council (MRC) score at first awakening (r = 0.383, P = 0.026) and at ICU discharge (r = 0.503, P = 0.002). Different physiotherapeutic strategies showed no effect on the ISI [sPT 0.029 (0.019/0.053) (mg/min/kg)/(mU/L) vs. pPT 0.026 (0.023/0.041) (mg/min/kg)/(mU/L) vs. pPT+ 0.029 (0.023/0.042) (mg/min/kg)/(mU/L); P = 0.919]. Regardless of the physiotherapeutic strategy metabolic flexibility was reduced. Relative change of lactate/pyruvate ratio during HE clamp is as follows: sPT 0.09 (-0.13/0.27) vs. pPT 0.07 (-0.16/0.31) vs. pPT+ -0.06 (-0.19/0.16), P = 0.729, and relative change of glycerol concentration: sPT -0.39 (-0.8/-0.12) vs. pPT -0.21 (-0.33/0.07) vs. pPT+ -0.21 (-0.44/-0.03), P = 0.257. The majority of ICU patients showed abnormal localization of GLUT4 with membranous GLUT4 distribution in 37.5% (3 of 8) of ICU patients receiving sPT, in 42.9% (3 of 7) of ICU patients receiving pPT, and in 53.8% (7 of 13) of ICU patients receiving pPT+ (no statistical testing possible). CONCLUSIONS: Our data suggest that a higher duration of muscle activating measures had no impact on insulin sensitivity or metabolic flexibility in critically ill patients with sepsis-related multiple organ failure.