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In response to excitation of skeletal muscle fibers, trains of action potentials induce changes in the configuration of the dihydropyridine receptor (DHPR) anchored in the tubular membrane which opens the Ca2+ release channel in the sarcoplasmic reticulum membrane. The DHPR also functions as a voltage-gated Ca2+ channel that conducts L-type Ca2+ currents routinely recorded in mammalian muscle fibers, which role was debated for more than four decades. Recently, to allow a closer look into the role of DHPR Ca2+ influx in mammalian muscle, a knock-in (ki) mouse model (ncDHPR) carrying mutation N617D (adjacent to domain II selectivity filter E) in the DHPRα1S subunit abolishing Ca2+ permeation through the channel was generated [Dayal et al., 2017]. In the present study, the Mn2+ quenching technique was initially intended to be used on voltage-clamped muscle fibers from this mouse to determine whether Ca2+ influx through a pathway distinct from DHPR may occur to compensate for the absence of DHPR Ca2+ influx. click here Surprisingly, while N617D DHPR muscle fibers of the ki mouse do not conduct Ca2+, Mn2+ entry and subsequent quenching did occur because Mn2+ was able to permeate and produce L-type currents through N617D DHPR. N617D DHPR was also found to conduct Ba2+ and Ba2+ currents were strongly blocked by external Ca2+. Ba2+ permeation was smaller, current kinetics slower and Ca2+ block more potent than in wild-type DHPR. These results indicate that residue N617 when replaced by the negatively charged residue D is suitably located at entrance of the pore to trap external Ca2+ impeding in this way permeation. Because Ba2+ binds with lower affinity to D, Ba2+ currents occur, but with reduced amplitudes as compared to Ba2+ currents through wild-type channels. We conclude that mutations located outside the selectivity filter influence channel permeation and possibly channel gating in a fully differentiated skeletal muscle environment.

This study aimed to investigate the mental state of medical staff and medical students in the early stages of the SARS-CoV-2 outbreak, as well as analyze the risk factors of serious mental illness (SMI), so as to provide a scientific basis for further psychological intervention and management.

A cross-sectional survey was conducted from February 2-7, 2020. The Kessler 6 Psychological Distress Scale and a general information questionnaire were administered on-line to a convenience sample of 548 medical staff and medical students in China. Multivariate binary logistic regression analysis was used to screen the risk factors of SMI in medical staff and medical students.

Of the 505 respondents in the final analysis, 188 (37.23%) were at high risk of SMI. Respondents were at significantly higher risk of SMI if they had been suspected of being infected with the SARS-CoV-2 (OR=7.00, 95% CI 1.19-41.14), had relatives suspected of being infected with the SARS-CoV-2 (OR=23.60, 95% CI 1.11-501.30), felt concerned tly stages of the SARS-CoV-2 outbreak and identify the factors associated with SMI which can be used to formulate psychological interventions to improve the mental health. The independent risk factors for SMI among them are suspicion that they or relatives were infected with the SARS-CoV-2, greater interest in media reports about the epidemic, frequency of recent dreams related to SARS-CoV-2, difficulty in controlling emotions during the epidemic, and hours spent watching outbreaks per day.

To compare local ganglion cell-inner plexiform layer (GCIPL) thickness measurements between 2 OCT devices and to explore factors that may influence the difference in measurements.

Cross-sectional study.

Sixty-nine glaucoma eyes (63 patients) with evidence of central damage or mean deviation (MD) of -6.0 dB or worse on a 24-2 visual field (VF).

Cirrus and Spectralis OCT macular volume scans were exported, data from the central 20° of both OCT devices were centered and aligned, and 50× 50 arrays of 0.4°× 0.4° superpixels were created. We estimated nonparametric (Spearman’s) correlations and used Bland-Altman plots to compare GCIPL thickness measurements between the two OCTs at the superpixel level. Factors that may have influenced the differences between thickness measurements between the two devices were explored with linear mixed models.

Pooled and individual-eye Spearman’s correlation and agreement between thickness measurements from the two devices.

The median 24-2 VF MD was -6.8 dB (interquartiuenced by the location of superpixels and their thickness.

Sudden death risk stratification of patients with left ventricular systolic dysfunction remains challenging. Retrospective studies have suggested N-terminal pro-B-type natriuretic peptide (NT-proBNP) may be a useful risk stratification tool.

The purpose of this study was to ascertain the utility of NT-proBNP as a predictor of appropriate implantable cardioverter-defibrillator (ICD) therapies in primary prevention ICD recipients.

This was a prospective study of 342 stable patients with left ventricular ejection fraction ≤40% who received a primary prevention ICD. NT-proBNP assay was performed at the time of device implant and used as a dichotomized variable (1st-3rd NT-proBNP quartiles vs 4th NT-proBNP quartile) to predict primary (appropriate ICD therapies) and secondary (death, ICD-deactivation, chronic inotropic support, transplant) outcomes.

Median follow-up was 35.0 months (interquartile range 15.2-55.3). In unadjusted analyses, NT-proBNP predicted both primary (hazard ratio [HR] 1.89; 95% confideot predict all-cause mortality.

In multivariable analysis, NT-proBNP is a reasonable and specific predictor of future appropriate device therapies in primary prevention ICD recipients. In contrast, adjusted NT-proBNP does not predict all-cause mortality.

Infra-red and thermal imaging enable wireless systems to monitor patients’ vital signs and absence of wires may improve patient experiences. No studies have explored staff perceptions of the concept of this specific type of technology in the adult population. Understanding existing working systems before introducing technology could improve adoption.

We conducted semi-structured interviews with Intensive Care Unit (ICU) staff exploring perceptions of wireless patient monitoring. We used the Systems Engineering Initiative for Patient Safety (SEIPS) model to guide thematic analysis.

We identified usability themes relating to staff perceptions of current patient monitoring experiences, staff perceptions of patient/relative expectations of ICU care, troubleshooting, hierarchy of monitoring, and consensus of trust.

The concept of wireless monitoring has perceived benefits for patients and staff. The Systems Engineering Initiative for Patient Safety model guided a systems-based exploratory evaluation. Results highlight the social and environmental factors which may influence usability, adoption, or abandonment of wireless technology in the ICU.