Myosin-5 varies its step length to carry cargo straight along the irregular F-actin track.

Molecular motors employ chemical energy to generate unidirectional mechanical output against a track while navigating a chaotic cellular environment, potential disorder on the track, and against Brownian motion. Nevertheless, decades of nanometer-precise optical studies suggest that myosin-5a, one of the prototypical molecular motors, takes uniform steps spanning 13 subunits (36 nm) along its F-actin track. Here, we use high-resolution interferometric scattering microscopy to reveal that myosin takes strides spanning 22 to 34 actin subunits, despite walking straight along the helical actin filament. We show that cumulative angular disorder in F-actin accounts for the observed proportion of each stride length, akin to crossing a river on variably spaced stepping stones. Electron microscopy revealed the structure of the stepping molecule. Our results indicate that both motor and track are soft materials that can adapt to function in complex cellular conditions.

Myosin-5 varies its steps along the irregular F-actin track.

Molecular motors employ chemical energy to generate unidirectional mechanical output against a track. By contrast to the majority of macroscopic machines, they need to navigate a chaotic cellular environment, potential disorder in the track and Brownian motion. Nevertheless, decades of nanometer-precise optical studies suggest that myosin-5a, one of the prototypical molecular motors, takes uniform steps spanning 13 subunits (36 nm) along its F-actin track. Here, we use high-resolution interferometric scattering (iSCAT) microscopy to reveal that myosin takes strides spanning 22 to 34 actin subunits, despite walking straight along the helical actin filament. We show that cumulative angular disorder in F-actin accounts for the observed proportion of each stride length, akin to crossing a river on variably-spaced stepping stones. Electron microscopy revealed the structure of the stepping molecule. Our results indicate that both motor and track are soft materials that can adapt to function in complex cellular conditions.

Ventricular assist device implantation in a patient with systemic right ventricle and pectus excavatum.

Systemic right ventricular failure is a common finding in patients with transposition of the great arteries. Some of these patients require ventricular assist device implantation. We describe the feasibility of HeartMate 3 [Abbott, Illinois, United States] implantation in a patient with transposition of the great arteries, high human leukocyte antigen sensitization, and severe pectus excavatum using a two-stage approach. Learning objectives: 1.To notice the challenges faced while implanting HeartMate 3 [Abbott, Illinois, United States] in patients with congenital heart disease and anatomical limitations.2.To understand that despite the difficulties, HeartMate 3 implantation is possible, worthwhile, and sometimes the only choice in a patient with end-stage heart failure and congenital heart disease.

Conservative initial postoperative anticoagulation strategy after HeartMate 3 left ventricular assist device implantation.

INTRODUCTION: Although anticoagulation therapy is mandated after implantation of a left ventricular assist device (LVAD), postoperative bleedings and reoperations occur relatively frequently and are associated with worse outcomes. We evaluated the use of a conservative postoperative anticoagulation protocol in patients implanted with a HeartMate 3 (HM3) LVAD. METHODS: In a single-centre retrospective analysis of postoperative outcomes after HM3 LVAD implantation, a standard (old) anticoagulation protocol (i.e. early, full-dose anticoagulation with low-molecular weight heparin and overlapping vitamin K antagonist) was compared with a new conservative anticoagulation protocol (i.e. slow initiation of vitamin K antagonists without overlapping heparin). Main outcomes were changes in international normalised ratio (INR), lactate dehydrogenase (LDH), bleeding and/or tamponade events requiring reoperation, length of stay and adverse events. RESULTS: In total, 73 patients (48 in old vs 25 in new protocol group) were evaluated. Mean age was 56 years (standard deviation 13) and most patients (78%) were males. Changes in INR and LDH in the first 14 days were similar in both groups (p = 0.50 and p = 0.997 for interaction, respectively). Number of bleeding/tamponade events requiring reoperation was lower in the new than in the old protocol group (4% vs 33%, p = 0.005). Postoperative 30-day mortality was similar, and we observed no thromboembolic events. Median (25th-75th percentiles) total length of postoperative hospital stay (27 (25-41) vs 21 (19-27) days, p < 0.001) and length of intensive care unit stay (5 (2-9) vs 2 (2-5) days, p = 0.022) were significantly shorter in the new protocol group. CONCLUSION: These retrospective data suggest that conservative slow initiation of anticoagulation therapy after HM3 LVAD implantation is associated with less bleeding/tamponade events requiring reoperation, a similar safety profile and a shorter duration of stay than the currently advised standard anticoagulation protocol.

Short-Term Trends in Elbow Ulnar Collateral Ligament Surgery in Collegiate Baseball Players: An Analysis of 25,587 Player-Years.

BACKGROUND: Trends over time in the incidence of ulnar collateral ligament (UCL) surgeries in National Collegiate Athletic Association Division I baseball players are currently unknown. PURPOSE/HYPOTHESIS: The purpose of this study was to evaluate the trends in UCL surgeries over 3 years in Division I baseball programs. We hypothesized that surgical injuries would be consistently high over the course of the study. STUDY DESIGN: Descriptive epidemiology study. METHODS: Athletic trainers from Division I baseball programs were invited to participate in an electronic survey over 3 seasons. A total of 155 baseball programs agreed to participate in 2017, 294 programs participated in 2018, and 296 programs participated in 2019. After each of the 3 collegiate baseball seasons, the athletic trainer from each program entered anonymous, detailed descriptive data and surgical information on injured players into a secured database. RESULTS: During the 3 years of this study, 100% of the enrolled programs successfully completed the survey (155/155 in year 1, 294/294 in year 2, and 296/296 in year 3). This registry of 745 completed surveys over 3 years represented 25,587 player-years from Division I collegiate baseball. The percentage of programs with at least 1 UCL surgery during this time was 57% in 2017, 51% in 2018, and 49% in 2019. The majority of these players were pitchers (84% overall from the 3 years). Seniors underwent a significantly lower percentage of the UCL surgeries (8% in 2017, 10% in 2018, and 13% in 2019) than did underclassmen. Surgeries were performed most often in-season and least often during the preseason. A slight majority of players undergoing surgery originated from warm-weather states, but the number of these players was never significantly higher than was the number of players from cold-weather states. Most surgeries performed each year were UCL reconstruction, but the percentage of UCL repair with ligament augmentation increased each year (10% UCL repairs in 2017, 20% in 2018, and 25% in 2019). CONCLUSION: UCL injuries requiring surgery were found to be a major source of morbidity in Division I collegiate baseball, supporting our hypothesis. This study can serve as a baseline for tracking long-term trends in UCL surgeries in collegiate baseball.

Distinguishing Alzheimer's Disease Patients and Biochemical Phenotype Analysis Using a Novel Serum Profiling Platform: Potential Involvement of the VWF/ADAMTS13 Axis.

It is important to develop minimally invasive biomarker platforms to help in the identification and monitoring of patients with Alzheimer's disease (AD). Assisting in the understanding of biochemical mechanisms as well as identifying potential novel biomarkers and therapeutic targets would be an added benefit of such platforms. This study utilizes a simplified and novel serum profiling platform, using mass spectrometry (MS), to help distinguish AD patient groups (mild and moderate) and controls, as well as to aid in understanding of biochemical phenotypes and possible disease development. A comparison of discriminating sera mass peaks between AD patients and control individuals was performed using leave one [serum sample] out cross validation (LOOCV) combined with a novel peak classification valuation (PCV) procedure. LOOCV/PCV was able to distinguish significant sera mass peak differences between a group of mild AD patients and control individuals with a p value of 10-13. This value became non-significant (p = 0.09) when the same sera samples were randomly allocated between the two groups and reanalyzed by LOOCV/PCV. This is indicative of physiological group differences in the original true-pathology binary group comparison. Similarities and differences between AD patients and traumatic brain injury (TBI) patients were also discernable using this novel LOOCV/PCV platform. MS/MS peptide analysis was performed on serum mass peaks comparing mild AD patients with control individuals. Bioinformatics analysis suggested that cell pathways/biochemical phenotypes affected in AD include those involving neuronal cell death, vasculature, neurogenesis, and AD/dementia/amyloidosis. Inflammation, autoimmunity, autophagy, and blood-brain barrier pathways also appear to be relevant to AD. An impaired VWF/ADAMTS13 vasculature axis with connections to F8 (factor VIII) and LRP1 and NOTCH1 was indicated and is proposed to be important in AD development.

Frailty screening by Geriatric-8 and 4-meter gait speed test is feasible and predicts postoperative complications in elderly colorectal cancer patients.

INTRODUCTION: Identification of frail older colorectal cancer patients might help to select those prone to adverse events and may lead to adjustment of treatment plans. However, the prognostic validity of screening for frailty is unknown. METHODS: This retrospective study evaluates colorectal cancer patients ≥70 years who underwent elective surgery between May 2016 and December 2018. The Geriatric-8 (G8) and 4-m gait speed test (4MGST) were used as frailty screening tools. According to hospital guidelines, patients were referred to a geriatrician when screening was indicative for frailty (G8 ≤ 14 and/or 4MGST < 1 m/s). Patients were categorized as fit, vulnerable or frail by comprehensive geriatric assessment (CGA). The clinical implications and prognostic validity of frailty screening and CGA were evaluated. RESULTS: 149 patients were included, of whom 132 (89%) were screened for frailty. Frailty was suspected in 40% of screened patients (n = 53) of whom 89% (n = 47) was referred for CGA. A higher complication rate was seen in patients with G8 ≤ 14 and/or 4MGST < 1 m/s compared to those with G8 > 14 and 4MGST ≥1 m/s (respectively 62% versus 28%,p < 0.001). Pneumonia (21% versus 6%, p = 0.013) and cardiac complications (11% versus 4%, p = 0.093) were more prevalent in patients with G8 ≤ 14 and/or 4MGST < 1 m/s. CGA identified frail patients as a group with a high complication rate of 68%. CONCLUSION: Screening for frailty with subsequent referral for CGA is feasible in older colorectal cancer patients. Our study suggests that screening for frailty by G8 + 4MGST can identify patients with higher risk for postoperative complications.

Serum discrimination and phenotype assessment of coronary artery disease patents with and without type 2 diabetes prior to coronary artery bypass graft surgery.

Diabetes Mellitus (DM) accelerates coronary artery disease (CAD) and atherosclerosis, the causes of most heart attacks. The biomolecules involved in these inter-related disease processes are not well understood. This study analyzes biomolecules in the sera of patients with CAD, with and without type (T) 2DM, who are about to undergo coronary artery bypass graft (CABG) surgery. The goal is to develop methodology to help identify and monitor CAD patients with and without T2DM, in order to better understand these phenotypes and to glean relationships through analysis of serum biomolecules. Aorta, fat, muscle, and vein tissues from CAD T2DM patients display diabetic-related histologic changes (e.g., lipid accumulation, fibrosis, loss of cellularity) when compared to non-diabetic CAD patients. The patient discriminatory methodology utilized is serum biomolecule mass profiling. This mass spectrometry (MS) approach is able to distinguish the sera of a group of CAD patients from controls (p value 10-15), with the CAD group containing both T2DM and non-diabetic patients. This result indicates the T2DM phenotype does not interfere appreciably with the CAD determination versus control individuals. Sera from a group of T2DM CAD patients however are distinguishable from non-T2DM CAD patients (p value 10-8), indicating it may be possible to examine the T2DM phenotype within the CAD disease state with this MS methodology. The same serum samples used in the CAD T2DM versus non-T2DM binary group comparison were subjected to MS/MS peptide structure analysis to help identify potential biochemical and phenotypic changes associated with CAD and T2DM. Such peptide/protein identifications could lead to improved understanding of underlying mechanisms, additional biomarkers for discriminating and monitoring these disease conditions, and potential therapeutic targets. Bioinformatics/systems biology analysis of the peptide/protein changes associated with CAD and T2DM suggested cell pathways/systems affected include atherosclerosis, DM, fibrosis, lipogenesis, loss of cellularity (apoptosis), and inflammation.

A Comparative Study of Modern and Heirloom Wheat on Indicators of Gastrointestinal Health.

Wheat consumption has declined amid growing concerns about gluten-sensitivity. To determine if genetic manipulation of wheat contributes to systemic and localized gut inflammation, we compared the effects of the modern variety Gallagher and a blend of two heirloom varieties, Turkey and Kharkof, on measures of gut inflammation, structural characteristics, and barrier integrity under normal and Western diet (WD) conditions in C57BL/6 mice. Indicators of gut inflammation, including lymphocyte infiltration and cytokine expression, were largely unaffected by WD or wheat, although WD elevated interferon-γ (Ifng) and heirloom varieties modestly reduced interleukin-17 (Il17) in the context of WD. WD negatively affected jejunal villi structure, while the modern variety improved villi structure in the ileum. Relative mRNA and tight junction proteins and serum lipopolysaccharide binding protein were unaltered by WD or wheat. These findings indicate that the modern variety did not compromise barrier function or contribute to gut inflammation compared to its heirloom predecessor.

Intrapelvic Retroperitoneal Synovial Sarcoma in a 15-Year-Old Adolescent Girl: A Case Report and Review of the Literature.

Synovial sarcomas are a rare subtype of soft tissue sarcomas mostly located in the lower extremities. The authors report a case of synovial sarcoma in a 15-year-old adolescent girl with several unusual features including age, intrapelvic retroperitoneal location of the primary tumor, and presentation with right abdominal tenderness and compression of the iliac vessels with thrombosis of the right iliac and femoral vein.

Heart Transplantation in Systemic Sclerosis: New Impulses for Conventional Scleroderma Transplantation Regimen and Scleroderma Diagnostic Monitoring: 2 Case Reports.

BACKGROUND: Although low (but increasing) rates of lung/lung-heart transplantations of scleroderma (systemic sclerosis [SSc]) patients have been reported, exclusive heart transplantation is a rare approach for treatment of heart failure due to SSc. CASES: We report on 2 cases of SSc patients receiving a heart transplantation (HTx) due to severe and progressive right heart failure without pulmonary artery hypertension. One patient received a hepatitis C virus (HCV)-positive donor heart and recovered excellently from viral transmission after administration of a direct-acting antiviral (DAA) regimen. This is the first published case of an SSc patient who underwent HTx using an HCV-positive donor heart. The clinical course of both patients was monitored by different serum SSc biomarkers. Only xylosyltransferase activity proved to be a promising biomarker for disease stage determination and therapeutic monitoring, precisely reflecting fibrotic remodeling and successful organ recovery. CONCLUSIONS: Successful implementation of the 2 cases described here demonstrates that HTx is a safe and effective therapeutic option for defined SSc sub-patient groups despite the progressive character of the underlying disease. In the future, xylosyltransferase activity might be conducive to simplify the identification of patients with low systemic involvement but a strong indication for single heart transplantation. Finally, we demonstrate that treatment of HCV viral transmission from HCV-positive donor to organ recipient using DAA gives us new opportunities to consider HCV-positive donor organs for HTx and might reveal new possibilities to ease the lack of donor organs.

Incidence of Elbow Ulnar Collateral Ligament Surgery in Collegiate Baseball Players.

BACKGROUND: Recent reports have highlighted the progressive increase in the incidence of ulnar collateral ligament (UCL) injuries to the elbow in baseball players of all levels. However, knowledge of the incidence and other epidemiological factors regarding UCL injuries, specifically in college baseball players, is currently lacking. PURPOSE: To evaluate, over a period of 1 year, the incidence of UCL injuries requiring surgery in National Collegiate Athletic Association (NCAA) Division I baseball programs. STUDY DESIGN: Descriptive epidemiology study. METHODS: A total of 155 Division I collegiate baseball programs agreed to participate in the study. Demographics (position, year, background [location of high school]) for all players on these rosters were obtained from public websites. At the conclusion of the 2017 collegiate baseball season, the athletic trainer for each program entered anonymous, detailed information on injured players through an electronic survey into a secured database. RESULTS: All 155 teams enrolled in the study completed the electronic survey. Of the 5295 collegiate baseball players on these rosters, 134 underwent surgery for an injured UCL (2.5% of all eligible athletes), resulting in a team surgery rate of 0.86 per program for 1 year. These 134 players came from 88 teams, thus 56.8% of the study teams underwent at least 1 surgery during the year. The surgery rate was 2.5 per 100 player-seasons for all players and was significantly higher among pitchers (4.4/100 player-seasons) than nonpitchers (0.7/100 player-seasons). The surgery rate was also significantly higher in underclassmen (3.1/100 player-seasons among freshmen and sophomores) than upperclassmen (1.9/100 player-seasons among juniors and seniors) (incidence rate ratio, 1.7; 95% CI, 1.1-2.4). Players from traditionally warm-weather states did not undergo UCL surgery at a significantly different rate from players from traditionally cold-weather states (2.7/100 player-seasons vs 2.1/100 player-seasons, respectively). Nearly half of surgeries (48.5%) were performed during the baseball season. CONCLUSION: The incidence of UCL surgeries in NCAA Division I collegiate baseball players represents substantial morbidity to this young athletic population. Risk factors for injuries requiring surgery include being a pitcher and an underclassman. Awareness of these factors should be considered in injury prevention programs. Furthermore, this initial study can serve as a foundation for tracking these surgical injuries in future years and then identifying trends over time.

Exposure to a specific time-varying electromagnetic field inhibits cell proliferation via cAMP and ERK signaling in cancer cells.

Exposure to specific electromagnetic field (EMF) patterns can affect a variety of biological systems. We have shown that exposure to Thomas-EMF, a low-intensity, frequency-modulated (25-6 Hz) EMF pattern, inhibited growth and altered cell signaling in malignant cells. Exposure to Thomas-EMF for 1 h/day inhibited the growth of malignant cells including B16-BL6 mouse melanoma cells, MDA-MB-231, MDA-MB-468, BT-20, and MCF-7 human breast cancer and HeLa cervical cancer cells but did not affect non-malignant cells. The Thomas-EMF-dependent changes in cell proliferation were mediated by adenosine 3',5'-cyclic monophosphate (cAMP) and extracellular-signal-regulated kinase (ERK) signaling pathways. Exposure of malignant cells to Thomas-EMF transiently changed the level of cellular cAMP and promoted ERK phosphorylation. Pharmacologic inhibitors (SQ22536) and activators (forskolin) of cAMP production both blocked the ability of Thomas-EMF to inhibit cell proliferation, and an inhibitor of the MAP kinase pathway (PD98059) was able to partially block Thomas-EMF-dependent inhibition of cell proliferation. Genetic modulation of protein kinase A (PKA) in B16-BL6 cells also altered the effect of Thomas-EMF on cell proliferation. Cells transfected with the constitutively active form of PKA (PKA-CA), which interfered with ERK phosphorylation, also interfered with the Thomas-EMF effect on cell proliferation. The non-malignant cells did not show any EMF-dependent changes in cAMP levels, ERK phosphorylation, or cell growth. These data indicate that exposure to the specific Thomas-EMF pattern can inhibit the growth of malignant cells in a manner dependent on contributions from the cAMP and MAP kinase pathways. Bioelectromagnetics. 39;217-230, 2018. © 2017 Wiley Periodicals, Inc.

Factors that influence the severity of post-stroke depression.

AIM: The aim of this paper was to investigate whether the extent of neurological impairment, the location of ischemic lesions due to stroke are associated with the severity of post-stroke depression. MATERIALS AND METHODS: The study included 82 patients, who were diagnosed with acute ischemic stroke and post-stroke depression and were admitted to the Neurology Clinic of Cluj-Napoca County Emergency Hospital between 2009 and 2011. A head MRI was performed with a 1.5 Tesla. Psychometric assessment was performed by using several scales, including the Beck Depression Inventory and the Mini-Mental State Examination. The National Institutes of Health Stroke Scale (NIHSS) and the Barthel Index of Activities of Daily Living were used to produce a complete neurological assessment. RESULTS: Patients with severe depression had a lower score on the Quality of Life Scale (QOLS) and higher scores for the Barthel index, NIHSS and MMSE. A stroke located in the basal nuclei increased the probability of severe depression. The patients with fewer lesions (1-2) had a greater chance of developing mild or moderate depression compared to the patients with 3-4 lesions. A frontal localization of the stroke was almost twice as common in patients with severe depression. If the stroke affected the left hemisphere, there was a higher probability of severe depression. In multivariate analysis, a basal nuclei lesion, a left hemisphere stroke location, and an NIHSS score >11 were all independently associated with severe depression. CONCLUSION: The location of the stroke and the NIHSS score could be related to the severity of post-stroke depression. Abbreviations: NIHSS = The National Institutes of Health Stroke Scale; QQL = Quality of life Scale; BDI = Beck Depression Inventory; MMSE = Mini-Mental State Examination; PSD = Post-stroke depression; MRI = Magnetic resonance imaging.

Serum Monitoring and Phenotype Identification of Stage I Non-Small Cell Lung Cancer Patients.

A stage I non-small cell lung cancer (NSCLC) serum profiling platform is presented which is highly efficient and accurate. Test sensitivity (0.95) for stage I NSCLC is the highest reported so far. Test metrics are reported for discriminating stage I adenocarcinoma vs squamous cell carcinoma subtypes. Blinded analysis identified 23 out of 24 stage I NSCLC and control serum samples. Group-discriminating mass peaks were targeted for tandem mass spectrometry peptide/protein identification, and yielded a lung cancer phenotype. Bioinformatic analysis revealed a novel lymphocyte adhesion pathway involved with early-stage lung cancer.

The effects of electromagnetic fields on B16-BL6 cells are dependent on their spatial and temporal character.

Exposure to low intensity, low frequency electromagnetic fields (EMF) has effects on several biological systems. Spatiotemporal characteristics of these EMFs are critical. The effect of several complex EMF patterns on the proliferation of B16-BL6 mouse melanoma cells was tested. Exposure to one of these patterns, the Thomas-EMF, inhibited cell proliferation and promoted calcium uptake. The Thomas-EMF is coded from a digital-to-analog file comprised of 849 points, which provides power to solenoids and can be set to alter timing, intensity, and duration of variable EMF. Setting the point duration to 3 ms generated a time-varying EMF pattern which began at 25 Hz and slowed to 6 Hz over a 2.5 s repeat. Exposing B16-BL6 cells to Thomas-EMF set to 3 ms for 1 h/day inhibited cell proliferation by 40% after 5 days, while setting the point duration to 1, 2, 4, or 5 ms had no effect on cell proliferation. Similarly, exposing cells to Thomas-EMF set to 3 ms promoted a three-fold increase in calcium uptake after 1 h, while the other timings had no effect. Exposure to Thomas-EMF for as short as 15 min/day slowed cell proliferation, but exposure for 1 h/day was optimal. This corresponded to the effect on calcium uptake where uptake was detected after 15 min exposure and was maximal by 1 h of treatment. Studies show that the specific spatiotemporal character of EMF is critical in mediating their biological activities. Bioelectromagnetics. 38:165-174, 2017. © 2016 Wiley Periodicals, Inc.

Cerebrolysin and early neurorehabilitation in patients with acute ischemic stroke: a prospective, randomized, placebo-controlled clinical study.

Background - Stroke represents one of the most important causes of permanent physical or mental disability. A number of recent advances in recovery have reinforced the idea that pharmacological intervention combined with a specific rehabilitation therapy can reduce disability after stroke. Objective - The aim of this trial was to demonstrate the hypothesis that the association of pharmacological treatment with Cerebrolysin to early physical therapy can significantly stimulate the endogenous processes underlying the recovery after an ischemic stroke. Methods and Results - It was a prospective, randomized, double-blind, placebo-controlled clinical study. 60 patients were randomized either to 30 ml/ day Cerebrolysin or to Placebo for 10 consecutive days, starting in the first 24-48 hours after stroke. The pharmacological treatment was paired with early physical rehabilitation. The robust nonparametric evaluation of the National Institute for Health Stroke Scale (NIHSS) demonstrated a large superiority of Cerebrolysin relative to placebo on day 10 with a MW=0.79 (95% CI, 0.65-0.94), respectively on day 30 with MW=0.75 (95% CI, 0.60-0.89). Similar results were found with modified Ranking Scale (mRS) and Barthel Index (BI). Cerebrolysin was safe and well tolerated. Conclusions - Cerebrolysin had a beneficial effect on global neurological status and disability. The beneficial results of this study can be easily applied in the current clinical practice. Abbreviations: BI = Barthel Index; CB = Changes from Baseline; CI = Confidence interval; ICH = International Conference on Harmonization; ITT = intention-to-treat; LB = Lower Bound of Confidence Interval; mRS = modified Rankin Scale; MW = Mann-Whitney; NIHSS = National Institute for Health Stroke Scale; P = P-value; R = Valid Number Reference Group (Placebo); SD = standard deviation; T = Valid Number Test Group (Cerebrolysin); UB = Upper Bound of Confidence Interval.

Image quality method as a possible way of in situ monitoring of in-vessel mirrors in a fusion reactor.

The plasma-facing (first) mirrors in ITER will be subject to sputtering and/or contamination with rates that will depend on the precise mirror locations. The resulting influence of both these factors can reduce the mirror reflectance (R) and worsen the transmitted image quality (IQ). This implies that monitoring the mirror quality in situ is an actual desire, and the present work is an attempt towards a solution. The method we propose is able to elucidate the reason for degradation of the mirror reflectance: sputtering by charge exchange atoms or deposition of contaminated layers. In case of deposition of contaminants, the mirror can be cleaned in situ, but a rough mirror (due to sputtering) cannot be used anymore and has to be replaced. To demonstrate the feasibility of the IQ method, it was applied to mirror specimens coated with carbon film in laboratory conditions and to mirrors coated with contaminants during exposure in fusion devices (TRIAM-1M and Tore Supra), as well as to mirrors of different materials exposed to sputtering by plasma ions in the DSM-2 plasma stand (in IPP NSC KIPT).

Retention of Ultrasound Skills and Training in "Point-of-Care" Cardiac Ultrasound.

BACKGROUND: Although the growth of point-of-care ultrasound has resulted in a proliferation of teaching programs, few data exist on the maintenance of proficiency. The aim of this study was to evaluate the retention of cardiac ultrasound skills and training in physicians up to 7 years after a formal focused curriculum in residency. METHODS: Thirty internal medicine physicians, deemed proficient at graduation and having passed a practical examination that confirms imaging skills and knowledge base when a score of ≥80% correct is attained, were retested. Twenty graduates (the NOPREP group) did not study any relevant material, and 10 graduates (the PREP group) were encouraged to study online videos. Scores were categorized by length of time (1-7 years) from graduates' last performance of ultrasound. RESULTS: The mean original test score of the physicians was 90 ± 6%. With retesting NOPREP (n = 20), seven physicians were within 1 year of their last use, and five (71%) repassed the examination, scoring 80 ± 15%. Among the remaining 13 NOPREP physicians who had >1 year of nonuse, none repassed, scoring 58 ± 17%. In retesting PREP (n = 10), one physician was within 1 year of last use and repassed, scoring 95%. Among the remaining nine PREP physicians with >1 year since last use, three (33%) repassed (P = .05), scoring 72 ± 21%. Diagnostic knowledge was significantly higher when good-quality images were obtained. CONCLUSIONS: Learned skills in cardiac ultrasound diminish notably within 2 years of nonuse.