Development of a Sensor Technology to Objectively Measure Dexterity for Cardiac Surgical Proficiency.

BACKGROUND: Technical skill is essential for good outcomes in cardiac surgery. However, no objective methods exist to measure dexterity while performing surgery. The purpose of this study was to validate sensor-based hand motion analysis (HMA) of technical dexterity while performing a graft anastomosis within a validated simulator. METHODS: Surgeons at various training levels performed an anastomosis while wearing flexible sensors (BioStamp nPoint, MC10 Inc) with integrated accelerometers and gyroscopes on each hand to quantify HMA kinematics. Groups were stratified as experts (n = 8) or novices (n = 18). The quality of the completed anastomosis was scored using the 10 Point Microsurgical Anastomosis Rating Scale (MARS10). HMA parameters were compared between groups and correlated with quality. Logistic regression was used to develop a predictive model from HMA parameters to distinguish experts from novices. RESULTS: Experts were faster (11 ± 6 minutes vs 21 ± 9 minutes; P = .012) and used fewer movements in both dominant (340 ± 166 moves vs 699 ± 284 moves; P = .003) and nondominant (359 ± 188 moves vs 567 ± 201 moves; P = .02) hands compared with novices. Experts' anastomoses were of higher quality compared with novices (9.0 ± 1.2 MARS10 vs 4.9 ± 3.2 MARS10; P = .002). Higher anastomosis quality correlated with 9 of 10 HMA parameters, including fewer and shorter movements of both hands (dominant, r = -0.65, r = -0.46; nondominant, r = -0.58, r = -0.39, respectively). CONCLUSIONS: Sensor-based HMA can distinguish technical dexterity differences between experts and novices, and correlates with quality. Objective quantification of hand dexterity may be a valuable adjunct to training and education in cardiac surgery training programs.

Evaluation of the Addition of Angiotensin II in Patients With Shock After Cardiac Surgery at a Veterans Affairs Medical Center.

BACKGROUND: Vasoplegic shock occurs in up to 37% of cardiac surgery patients. We investigated the use of angiotensin II for treating vasoplegic shock in these patients. OBJECTIVES: We assessed clinical outcomes and mortality in patients undergoing cardiac surgery at our center between March 1, 2018 and October 31, 2020 who developed vasoplegic shock, comparing those who received angiotensin II with those who did not. METHODS: This was a retrospective chart review. Response to angiotensin II was defined as increase in or maintenance of mean arterial pressure (MAP) and decrease in background vasopressor dosage. RESULTS: Angiotensin II was administered to 7 patients (postoperatively in 4 patients [57.1%]) with vasoplegic shock and baseline norepinephrine equivalent (NEE) of 0.49 ± 0.08 µg/kg/min; 12 patients with vasoplegic shock did not receive angiotensin II. Within 3 hours of angiotensin II administration, NEE decreased by 38.0 ± 33.1%. Angiotensin patients were more likely to newly require renal replacement therapy (66.7% vs 9.1%, P = 0.03) and had a longer, although not statistically significant, postoperative stay (23.1 vs 14.0 days, P = 0.16). Despite higher NEE requirements at baseline (0.49 vs 0.30, P = 0.03) and over the next 48 hours in the angiotensin group, no between-group differences in 7-day mortality (14.3% vs 0.0%, P = 0.37) or 30-day mortality (28.6% vs 8.3%, P = 0.52) were noted. CONCLUSION AND RELEVANCE: In patients who developed vasoplegic shock after cardiac surgery, angiotensin II administration allowed immediate dosage reductions of other vasopressors while maintaining MAP. Despite its small sample size, this study adds to the paucity of data in these patients and highlights future research needs.

Telerehabilitation: Future of Phase II Cardiac Rehabilitation: Review of Preliminary Outcomes.

In this brief communication, we reported Telehealth Home-Based Cardiac Rehabilitation (CR) program structure and preliminary outcomes from patients that completed a 12-week program after coronary artery bypass graft surgery (CABG). We aim to advocate the use of Telerehabilitation as a Phase II CR in patients immediately after the CABG. This approach was innovative and encouraging because the patients were still in subacute phase. The program can serve as a continuation of care for the patients after being discharged from a hospital while regaining their functional ability at home. Our preliminary outcomes demonstrated improvements in resting heart rate, activity level, nutrition status, self-efficacy for managing cardiac diseases, muscle strength, endurance and depression. There were no adverse events during the virtual sessions. Patient satisfaction score was high.

Stepwise optimization of a Flexible Microtube Plasma (FµTP) as an ionization source for Ion Mobility Spectrometry.

The ionization source is the central system of analytical devices such as mass spectrometers or ion mobility spectrometers. In this study, a recently developed flexible microtube plasma (FµTP) is applied as an ionization source for a custom-made drift tube ion mobility spectrometer (IMS) for the first time. The FµTP is based on a highly miniaturized, robust and a small-footprint dielectric barrier discharge design with an outstanding ionization efficiency. In this study, the experimental setup of the FµTP was further improved upon to achieve optimal coupling conditions in terms of the ion mobility spectrometry sensitivity and the plasma gas consumption. One major focus of this study was the adjustment of the electrical operation parameters, in particular, the high voltage amplitude, frequency and duty cycle, in order to minimize the electric field disturbances and yield higher signals. Additionally, the consumption of helium plasma gas was reduced by refining the FµTP. It was found that the ionization efficiency could be significantly enhanced by increasing the plasma high voltage and through application of a duty cycle up to 90:10. Plasma gas flows could be reduced down to 3 mL min-1 by increasing the plasma high voltage amplitude. Furthermore, a smaller wire electrode design enables the operation of the FµTP with nitrogen and clean air. Moreover, detection limits of a homologous series of ketones in the range of 330 pptv (N2-FµTP, 2-decanone) down to 20 pptv (He-FµTP, 2-octanone) could be reached in the optimized setup. To sum up, this feasibility study demonstrates the potential of the optimized FµTP as a powerful ionization source for ion mobility spectrometry especially with regard to ionization efficiency.

Del Nido cardioplegia in coronary surgery: a propensity-matched analysis.

OBJECTIVES: Del Nido cardioplegia (DNC) has been shown to be safe in adults with normal coronary arteries who are undergoing valve surgery. This study compared the effects of DNC versus traditional blood-based cardioplegia on postoperative complications in patients who underwent coronary artery bypass grafting (CABG). METHODS: A retrospective analysis was performed on 863 patients who underwent CABG with DNC (n = 420) or control cardioplegia (CC) (n = 443) between 2014 and 2017. The full cohort of DNC and CC recipients, as well as propensity score-matched pairs, was compared regarding preoperative risk variables and outcomes. RESULTS: The DNC and CC groups showed no significant differences in mean cardiopulmonary bypass time (53.09 vs 52.10 min, P = 0.206) or aortic cross-clamp time (32.82 vs 33.28 min, P = 0.967). The groups also showed no difference in operative mortality (2.1% vs 2.5%, P = 0.734); however, DNC use resulted in lower rates of overall infections (1.7% vs 4.3%, P = 0.024), total sternal infections (0.9% vs 3.2%, P = 0.023), postoperative atrial fibrillation (23.8% vs 30.7%, P = 0.023) and postoperative ventricular tachycardia (0.5% vs 3.4%, P = 0.002). A propensity-matching analysis (n = 335 pairs) showed similar statistically significant decreases with DNC. CONCLUSIONS: In this large cohort of CABG patients, DNC was shown as a safe alternative to CC and was associated with lower postoperative dysrhythmia and infection rates. These findings show that DNC is safe and effective in patients whose operative interventions may require only single-dosing cardioplegia; its use in longer cases should be further explored given its low complication rate.

Simple Felt-Plug Closure Technique for Minimally Invasive Removal of a Centrifugal-Flow Left Ventricular Assist Device.

As the indications for implanting left ventricular assist devices have expanded, some patients are qualifying for device removal after myocardial recovery. Whereas explantation has been described for previous generations of devices, no standard procedures have been developed. Removal of centrifugal-flow devices has created the need for a plug to seal the apical ventriculotomy after pump removal. However, no commercially available products are available in the United States. We used a novel technique to fashion a plug from Teflon felt and a Dacron graft to enable minimally invasive explantation of a current-generation centrifugal-flow device in a 33-year-old woman.

Screening of semifluorinated n-alkanes by gas chromatography coupled to dielectric barrier discharge ionization mass spectrometry.

RATIONALE: The potential of an atmospheric pressure ionization source based on a dielectric barrier discharge in helium for the hyphenation of gas chromatography and mass spectrometry (GC/DBDI-MS) has been demonstrated only recently and for a limited range of compounds. Due to its 'soft' ionization properties and the possibility to choose from a variety of atmospheric pressure ionization MS instruments, GC/DBDI-MS has the potential to be an interesting alternative to 'classic' GC/MS techniques. METHODS: The hyphenation of GC with DBDI-MS at atmospheric pressure is used for the determination of semifluorinated n-alkanes in ski wax samples. RESULTS: Different to perfluorinated n-alkanes, which are typically detected as [M - F + O]- and [M - F]- , semifluorinated n-alkanes can be detected both in positive mode as [M - 3H + nO]+ and [M - H + nO]+ (n = 0, 1, 2, and 3) ions, as well as in negative mode as a fragment ion representing the fluorinated part of the respective semifluorinated n-alkane. The method allowed the sensitive detection of semifluorinated n-alkanes with achievable limits of detection (LODs) in the single digit pg range injected on column. To examine the applicability of the GC/DBDI-MS method, semifluorinated n-alkanes were determined in fluorinated ski waxes. Results were confirmed by complimentary GC/electron ionization MS measurements. CONCLUSIONS: The unique SFA ionization patterns serve for complementary unambiguous identification of semifluorinated n-alkane species in positive mode and screening of contained n-alkanes fluorinated chain lengths in negative mode.

Perceptual task induces saccadic adaptation by target selection.

Adaptation of saccades can be induced by different error signals, such as retinal position errors, prediction errors, or reinforcement learning. Recently, we showed that a shift in the spatial goal of a perceptual task can induce saccadic adaptation, in the absence of a bottom-up position error. Here, we investigated whether this top-down effect is mediated by the visibility of the task-relevant object, by reinforcement due to the feedback about the perceptual judgment or by a target selection mechanism. Participants were asked to discriminate visual stimuli arranged in a vertical compound. To induce adaptation, the discrimination target was presented at eccentric locations in the compound. In the first experiment, we compared adaptation with an easy and difficult discrimination. In the second experiment, we compared adaptation when feedback about the perceptual task was valid and when feedback was provided but was unrelated to performance. In the third experiment, we compared adaptation with instructions to fixate one of the elements in the compound-target selection-to the perceptual task condition-target selection and discrimination. To control for a bottom-up stimulus effect, we ran a fourth experiment in which the only instruction was to look at the compound. The saccade amplitude data were fitted by a two-state model distinguishing between an immediate and a gradual error correction process. We replicated our finding that a perceptual task can drive adaptation of saccades. Adaptation showed no effect of feedback reliability, nor an effect of the perceptual task beyond target selection. Adaptation was induced by a top-down signal since it was absent when there was no target selection instruction and no perceptual task. The immediate error correction was larger for the difficult than for the easy condition, suggesting that task difficulty affects mainly voluntary saccade targeting. In addition, the repetition of experiments one week later increased the magnitude of the gradual error correction. The results dissociate two distinct components of adaptation: an immediate and a gradual error correction. We conclude that perceptual-task induced adaptation is most likely due to top-down target selection within a larger object.

The required minimum length of video sequences for obtaining a reliable interobserver diagnosis in wrist arthroscopies.

PURPOSE: To examine the relationship between video length for wrist arthroscopy and interobserver reliability. MATERIALS AND METHODS: 100 consecutive wrist arthroscopies were documented by long and short videos of the radiocarpal and the midcarpal joints. The long videos were about twice as long as the short videos. They were presented randomly to two independent and blinded examiners. Their diagnoses were compared to the diagnoses made by the surgeon who performed the arthroscopies. Kappa coefficients were calculated. RESULTS: Kappa statistics were inconsistent and did not show that the long video provided an obvious advantage over the short video. The Kappa coefficients of the two examiners for the assessment of the cartilage status were 0.524 and 0.700 for the long videos and 0.465 and 0.639 for the short videos, respectively. The examiners diagnosed twice as many false-positive cartilage lesions on short videos than on long videos. The assessment of ligament lesions was more accurate on long than on short videos. CONCLUSIONS: The results confirmed the hypothesis that the reproducibility of diagnoses based on video documents was influenced by the length of the video sequences. Therefore, it may be advisable for video documentation to be done diligently. The video sequence of the radiocarpal joint should last about 60 s, and that of a midcarpal joint should last about 45 s. Videos of difficult joints should last appropriately longer. LEVEL OF EVIDENCE: Diagnostic II.

Lung Adenocarcinomas and Lung Cancer Cell Lines Show Association of MMP-1 Expression With STAT3 Activation.

Signal transducer and activator of transcription 3 (STAT3) is constitutively activated in the majority of lung cancer. This study aims at defining connections between STAT3 function and the malignant properties of non-small cell lung carcinoma (NSCLC) cells. To address possible mechanisms by which STAT3 influences invasiveness, the expression of matrix metalloproteinase-1 (MMP-1) was analyzed and correlated with the STAT3 activity status. Studies on both surgical biopsies and on lung cancer cell lines revealed a coincidence of STAT3 activation and strong expression of MMP-1. MMP-1 and tyrosine-phosphorylated activated STAT3 were found co-localized in cancer tissues, most pronounced in tumor fronts, and in particular in adenocarcinomas. STAT3 activity was constitutive, although to different degrees, in the lung cancer cell lines investigated. Three cell lines (BEN, KNS62, and A549) were identified in which STAT3 activitation was inducible by Interleukin-6 (IL-6). In A549 cells, STAT3 activity enhanced the level of MMP-1 mRNA and stimulated transcription from the MMP-1 promoter in IL-6-stimulated A549 cells. STAT3 specificity of this effect was confirmed by STAT3 knockdown through RNA interference. Our results link aberrant activity of STAT3 in lung cancer cells to malignant tumor progression through up-regulation of expression of invasiveness-associated MMPs.

SIAH2 antagonizes TYK2-STAT3 signaling in lung carcinoma cells.

The Janus tyrosine kinases JAK1-3 and tyrosine kinase-2 (TYK2) are frequently hyperactivated in tumors. In lung cancers JAK1 and JAK2 induce oncogenic signaling through STAT3. A putative role of TYK2 in these tumors has not been reported. Here, we show a previously not recognized TYK2-STAT3 signaling node in lung cancer cells. We reveal that the E3 ubiquitin ligase seven-in-absentia-2 (SIAH2) accelerates the proteasomal degradation of TYK2. This mechanism consequently suppresses the activation of STAT3. In agreement with these data the analysis of primary non-small-cell lung cancer (NSCLC) samples from three patient cohorts revealed that compared to lung adenocarcinoma (ADC), lung squamous cell carcinoma (SCC) show significantly higher levels of SIAH2 and reduced STAT3 phosphorylation levels. Thus, SIAH2 is a novel molecular marker for SCC. We further demonstrate that an activation of the oncologically relevant transcription factor p53 in lung cancer cells induces SIAH2, depletes TYK2, and abrogates the tyrosine phosphorylation of STAT1 and STAT3. This mechanism appears to be different from the inhibition of phosphorylated JAKs through the suppressor of cytokine signaling (SOCS) proteins. Our study may help to identify molecular mechanisms affecting lung carcinogenesis and potential therapeutic targets.

Workflows in cancer treatment and their influence upon clinical documentation.

To establish single source cancer documentation for a complete comprehensive cancer center CCC we performed a systematic analysis of diagnostic, therapeutic and documentation workflows for 13 cancer entities. Results suggest that we will need three types of clinical documentation to cover all cancer entities of the Erlangen CCC. We expect to have a workflow for solid entities with inpatient treatment, one for solid entities treated ambulatory and one for non solid cancer entities.

Dynamic integration of information about salience and value for saccadic eye movements.

Humans shift their gaze to a new location several times per second. It is still unclear what determines where they look next. Fixation behavior is influenced by the low-level salience of the visual stimulus, such as luminance, contrast, and color, but also by high-level task demands and prior knowledge. Under natural conditions, different sources of information might conflict with each other and have to be combined. In our paradigm, we trade off visual salience against expected value. We show that both salience and value information influence the saccadic end point within an object, but with different time courses. The relative weights of salience and value are not constant but vary from eye movement to eye movement, depending critically on the availability of the value information at the time when the saccade is programmed. Short-latency saccades are determined mainly by salience, but value information is taken into account for long-latency saccades. We present a model that describes these data by dynamically weighting and integrating detailed topographic maps of visual salience and value. These results support the notion of independent neural pathways for the processing of visual information and value.

Rapamycin and a hyaluronic acid-carboxymethylcellulose membrane did not lead to reduced adhesion formations in a rat abdominal adhesion model.

PURPOSE: Rapamycin, an immunosuppressive in transplant surgery, has an additional antiproliferative effect. The aim of this study was to investigate the potential protective effects of rapamycin on postoperative adhesion development. METHODS: Ten rats per group underwent midline incision laparotomy and adhesion induction including bowel sutures. Therapy groups received daily intraperitoneal rapamycin injections (1.5 mg/kg body weight) for 3 weeks postoperatively. Controls were rats without any postoperative treatment, rats receiving the rapamycin solvent or a hyaluronic acid-carboxymethylcellulose membrane (Seprafilm(™)). RESULTS: Postoperative rapamycin application led to enhanced adhesion development and there was a higher rate of wound infections. In addition, Seprafilm(™) did not reduce adhesions, in subgroups there were even more. CONCLUSIONS: Rapamycin is not recommendable for perioperative immunosuppression, it enhances adhesion development and leads to a higher rate of wound infections. Surprisingly, the established Seprafilm(™) membrane led to more adhesions in our experimental setting.

Evaluation of the invasion front pattern of squamous cell cervical carcinoma by measuring classical and discrete compactness.

The invasion front pattern of squamous cell carcinoma (SCC) is a conspicuous histological phenomenon, which is assessed without precise criteria. The current study was performed to introduce the classical (C(C)) and discrete compactness (C(D)) as new morphometric parameters for quantification of this pattern. A retrospective analysis of 76 surgically treated patients with cervical carcinoma was conducted and the pattern of invasion was qualitatively classified as closed, finger-like or diffuse, respectively, by two pathologists. After digitization of the histological slides with a field of view of 10.4 mm x 8.3mm, tumor areas were labeled and C(C) and C(D) were computed based on the drawings (binary images). Additionally, intraindividual variation of compactness was evaluated for 12 selected tumors. The qualitative pattern assessment by the pathologists was moderately reproducible with an interobserver agreement of 72% and a kappa coefficient of 0.44. The values of C(C) and C(D) referring to the invasion front patterns assigned by both pathologists were significantly different between the three classified groups (p< or =0.01 and p< or =0.0001), so that, both theoretically and in practice, compactness regards the same morphological feature. In due consideration of the analysis of the area under the ROC (receiver operating characteristic) curves and the variation coefficient of different tumor regions, C(D) is more suitable for practical use than C(C). Tumors with a microscopic invasion into the parametria and with lymph-vascular space invasion were found to have a lower value of C(D), which indicates a more diffuse pattern of invasion (p=0.028 and p=0.033). We conclude that the discrete compactness C(D) is a new and reproducible parameter for a computer assisted quantification of the invasion front pattern and, thus, defines a further phenotypic feature of SCC of the uterine cervix.

Signal transducer and activator of transcription 3 activation promotes invasive growth of colon carcinomas through matrix metalloproteinase induction.

Signal transducer and activator of transcription 3 (STAT3) is aberrantly activated in colorectal carcinomas (CRCs). Here, we define the relationship between STAT3 function and the malignant properties of colon carcinoma cells. Elevated activation of STAT3 enhances invasive growth of the CRC cell lines. To address mechanisms through which STAT3 influences invasiveness, the protease mRNA expression pattern of CRC biopsies was analyzed and correlated with the STAT3 activity status. These studies revealed a striking coincidence of STAT3 activation and strong expression of matrix metalloproteinases MMP-1, -3, -7, and -9. Immunohistological examination of CRC tumor specimens showed a clear colocalization of MMP-1 and activated STAT3. Experimentally induced STAT3 activity in CRC cell lines enhanced both the level of MMP-1 mRNA and secreted MMP-1 enzymatic activity. A direct connection of STAT3 activity and transcription from the MMP-1 promoter was shown by reporter gene experiments. Moreover, high-affinity binding of STAT3 to STAT recognition elements in both the MMP-1 and MMP-3 promoter was demonstrated. Xenograft tumors arising from implantation of CRC cells into nude mice showed simultaneous appearance and colocalization of p-Y-STAT3 and MMP-1 expression. Our results link aberrant activity of STAT3 in CRC to malignant tumor progression through upregulated expression of MMPs.

Lack of apoptotic protease activating factor-1 expression and resistance to hypoxia-induced apoptosis in cervical cancer.

PURPOSE: Clinical observations suggest that intratumoral hypoxia increases the aggressiveness of tumors through clonal selection of cancer cells that have lost their apoptotic potential. The aim of this study, therefore, was to investigate the expression of the proapoptotic protein apoptotic protease activating factor-1 (Apaf-1) in cervical cancers and to analyze its relation to intratumoral hypoxia and apoptosis. Furthermore, the effect of hypoxia and apoptosis on survival was examined. EXPERIMENTAL DESIGN: In 56 patients, intratumoral oxygenation measurements and subsequent needle biopsies were done. The obtained tissue was analyzed by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assays and by immunohistochemistry with an Apaf-1 antibody. RESULTS: Apaf-1 was expressed in 86% of cancers. The median apoptosis rate was 1.0%. There was no correlation between Apaf-1 expression and intratumoral hypoxia. However, Apaf-1 expression was negative in 37.5% of hypoxic cervical cancers (pO(2)

Juxtatumoral desmoplastic stromal reaction is associated with high tumor cell dissociation in squamous cell carcinomas of the uterine cervix.

There are different types of tumoral growth patterns invading host tissue. During tumor infiltration, cancer cells not only destroy the pre-existing extracellular matrix, but usually induce new matrix formation by activating the peritumoral stromal cells; that is, desmoplastic stromal reaction (DSR) at the front of invasion (juxtatumoral stroma). This study evaluates the association between different types of invasion and DSR. Eighty-eight squamous cell carcinomas (Fédération Internationale de Gynécologie et d'Obstétrique [FIGO] stage IB to IV) were evaluated histologically for different patterns of invasion (PI) using a 3-level scoring system (pushing, finger-like, and spray-like). Desmoplastic stromal reaction was scored from none to weak, moderate, or strong. The pattern of invasion and DSR were compared with patients' age, FIGO stage, clinical tumor size, tumor grade, and the presence of lymphovascular space involvement. Finger-like PI was the most common (72.7%), followed by the spray-like PI (27.3%), whereas pushing PI was not seen. Of the tumors, 23.9% showed no DSR; 51.1%, weak; 14.8%, moderate; and 10.2%, strong DSR. Tumors with spray-like PI showed a significantly stronger desmoplastic reaction compared with the finger-like PI (P < .0001) and were significantly associated with poor tumor cell differentiation (P = .018). Moderate or strong DSR was associated with G2 and G3 carcinomas (P = .027). No correlation was seen neither for PI and DSR to lymphovascular space involvement, FIGO stage, and tumor size. The intensity of DSR, as understood in the context of a remodeling of the juxtatumoral stroma to the infiltrative tumor growth, might be indicative of a highly dissociative tumor growth and is correlated to poorly differentiated tumors.