Identification and characterization of a nonbiological small-molecular mimic of a Zika virus conformational neutralizing epitope.

Antigenic similarities between Zika virus (ZIKV) and other flaviviruses pose challenges to the development of virus-specific diagnostic tools and effective vaccines. Starting with a DNA-encoded one-bead-one-compound combinatorial library of 508,032 synthetic, non-natural oligomers, we selected and characterized small molecules that mimic ZIKV epitopes. High-throughput fluorescence-activated cell sorter-based bead screening was used to select molecules that bound IgG from ZIKV-immune but not from dengue-immune sera. Deep sequencing of the DNA from the "Zika-only" beads identified 40 candidate molecular structures. A lead candidate small molecule "CZV1-1" was selected that correctly identifies serum specimens from Zika-experienced patients with good sensitivity and specificity (85.3% and 98.4%, respectively). Binding competition studies of purified anti-CZV1-1 IgG against known ZIKV-specific monoclonal antibodies (mAbs) showed that CZV1-1 mimics a nonlinear, neutralizing conformational epitope in the domain III of the ZIKV envelope. Purified anti-CZV1-1 IgG neutralized infection of ZIKV in cell cultures with potencies comparable to highly specific ZIKV-neutralizing mAbs. This study demonstrates an innovative approach for identification of synthetic non-natural molecular mimics of conformational virus epitopes. Such molecular mimics may have value in the development of accurate diagnostic assays for Zika, as well as for other viruses.

Correlations between heart sound components and hemodynamic variables.

Although the esophageal stethoscope is used for continuous auscultation during general anesthesia, few studies have investigated phonocardiographic data as a continuous hemodynamic index. In this study, we aimed to induce hemodynamic variations and clarify the relationship between the heart sounds and hemodynamic variables through an experimental animal study. Changes in the cardiac contractility and vascular resistance were induced in anesthetized pigs by administering dobutamine, esmolol, phenylephrine, and nicardipine. In addition, a decrease in cardiac output was induced by restricting the venous return by clamping the inferior vena cava (IVC). The relationship between the hemodynamic changes and changes in the heart sound indices was analyzed. Experimental data from eight pigs were analyzed. The mean values of the correlation coefficients of changes in S1 amplitude (ΔS1amp) with systolic blood pressure (ΔSBP), pulse pressure (ΔPP), and ΔdP/dt during dobutamine administration were 0.94, 0.96, and 0.96, respectively. The mean values of the correlation coefficients of ΔS1amp with ΔSBP, ΔPP, and ΔdP/dt during esmolol administration were 0.80, 0.82, and 0.86, respectively. The hemodynamic changes caused by the administration of phenylephrine and nicardipine did not correlate significantly with changes in the heart rate. The S1 amplitude of the heart sound was significantly correlated with the hemodynamic changes caused by the changes in cardiac contractility but not with the variations in the vascular resistance. Heart sounds can potentially provide a non-invasive monitoring method to differentiate the cause of hemodynamic variations.

Association between De Ritis ratio and intraoperative blood transfusion in patients undergoing surgical clipping of unruptured intracranial aneurysms: a single center, retrospective, propensity score-matched study.

BACKGROUND: Although elective surgery for unruptured intracranial aneurysms (UIA) has increased, few studies have evaluated the risk factors for transfusion during UIA surgery. We evaluated the association between the preoperative De Ritis ratio (aspartate transaminase/alanine transaminase) and the incidence of intraoperative transfusion in patients who had undergone surgical UIA clipping. METHODS: Patients who underwent surgical clipping of UIA were stratified into two groups according to the preoperative De Ritis ratio cutoff levels (< 1.54 and ≥ 1.54), and the propensity score (PS)-matching analysis was performed to compare the incidence of intraoperative transfusion. Logistic regression analyses were performed to determine the risk factors for intraoperative transfusion. Net reclassification improvement (NRI) and integrated discrimination improvement (IDI) analyses were performed to verify the improvement in the intraoperative transfusion predictive model upon addition of the De Ritis ratio. RESULTS: Intraoperative transfusion incidence was 15.4% (77/502). We observed significant differences in the incidence of intraoperative transfusion (16.2% vs. 39.7%, P = 0.004) between the groups after matching. In the logistic regression analyses, the De Ritis ratio ≥ 1.54 was an independent risk factor for transfusion (odds ratio [OR]: 3.04, 95% CI [1.53, 6.03], P = 0.002). Preoperative hemoglobin (Hb) value was a risk factor for transfusion (OR: 0.33, 95% CI [0.24, 0.47], P < 0.001). NRI and IDI analyses showed that the De Ritis ratio improved the intraoperative blood transfusion predictive models (P = 0.031 and P = 0.049, respectively). CONCLUSIONS: De Ritis ratio maybe a significant risk factor for intraoperative transfusion in UIA surgery.

Enhancing the performance of premature ventricular contraction detection in unseen datasets through deep learning with denoise and contrast attention module.

Premature ventricular contraction (PVC) is a common and harmless cardiac arrhythmia that can be asymptomatic or cause palpitations and chest pain in rare instances. However, frequent PVCs can lead to more serious arrhythmias, such as atrial fibrillation. Several PVC detection models have been proposed to enable early diagnosis of arrhythmias; however, they lack reliability and generalizability due to the variability of electrocardiograms across different settings and noise levels. Such weaknesses are known to aggravate with new data. Therefore, we present a deep learning model with a novel attention mechanism that can detect PVC accurately, even on unseen electrocardiograms with various noise levels. Our method, called the Denoise and Contrast Attention Module (DCAM), is a two-step process that denoises signals with a convolutional neural network (CNN) in the frequency domain and attends to differences. It focuses on differences in the morphologies and intervals of the remaining beats, mimicking how trained clinicians identify PVCs. Using three different encoder types, we evaluated 1D U-Net with DCAM on six external test datasets. The results showed that DCAM significantly improved the F1-score of PVC detection performance on all six external datasets and enhanced the performance of balancing both the sensitivity and precision of the models, demonstrating its robustness and generalization ability regardless of the encoder type. This demonstrates the need for a trainable denoising process before applying the attention mechanism. Our DCAM could contribute to the development of a reliable algorithm for cardiac arrhythmia detection under real clinical electrocardiograms.

Relationship between Preoperative Echocardiographic Parameters and the Incidence of Postoperative Complications in Patients Undergoing Clipping of Unruptured Intracranial Aneurysms: A Retrospective Cohort Study.

Background and Objectives: Preoperative echocardiography is widely performed in patients undergoing major surgeries to evaluate cardiac functions and detect structural abnormalities. However, studies on the clinical usefulness of preoperative echocardiography in patients undergoing cerebral aneurysm clipping are limited. Therefore, this study aimed to investigate the correlation between preoperative echocardiographic parameters and the incidence of postoperative complications in patients undergoing clipping of unruptured intracranial aneurysms. Materials and Methods: Electronic medical records of patients who underwent clipping of an unruptured intracranial aneurysm from September 2018 to April 2020 were retrospectively reviewed. Data on baseline characteristics, laboratory variables, echocardiographic parameters, postoperative complications, and hospital stays were obtained. Univariable and multivariable logistic regression analyses were performed to identify independent variables related to the occurrence of postoperative complications and prolonged hospital stay (≥8 d). Results: Among 531 patients included in the final analysis, 27 (5.1%) had postoperative complications. In multivariable logistic regression, the total amount of crystalloids infused (1.002 (1.001-1.003), p = 0.001) and E/e' ratio (1.17 (1.01-1.35), p = 0.031) were significant independent factors associated with the occurrence of a postoperative complication. Additionally, the maximal diameter of a cerebral aneurysm (1.13 (1.02-1.25), p = 0.024), total amount of crystalloids infused (1.001 (1.000-1.002), p = 0.031), E/A ratio (0.22 (0.05-0.95), p = 0.042), and E/e' ratio (1.16 (1.04-1.31), p = 0.011) were independent factors related to prolonged hospitalization. Conclusions: Echocardiographic parameters related to diastolic function might be associated with postoperative complications in patients undergoing clipping of unruptured intracranial aneurysms.

Total Intravenous Anesthesia Protocol for Decreasing Unacceptable Movements during Cerebral Aneurysm Clipping with Motor-Evoked Potential Monitoring: A Historical Control Study and Meta-Analysis.

Injury can occur during intraoperative transcranial motor-evoked potential (MEP) monitoring caused by patient movement related to insufficient neuromuscular blocking agent use. Here, we evaluated the incidence of unacceptable movements in patients undergoing intraoperative MEP monitoring following our anesthetic protocol. We reviewed the anesthesia records of 419 patients who underwent unruptured cerebral aneurysm clipping with intraoperative MEP monitoring. The anesthetic protocol included target-controlled infusion with a fixed effect-site propofol concentration of 3 µg/mL and an adjustable effect-site remifentanil concentration of 10-12 ng/mL. We compared our findings of the intraoperative parameters and incidence of spontaneous movement and respiration with those of published meta-analysis studies. Spontaneous movement and respiration occurred in one (0.2%) patient each. The meta-analysis included six studies. The pooled proportions of spontaneous movement and respiration were 6.9% (95% confidence interval [CI], 1.3-16.5%) and 4.1% (95% CI, 0.5-14.1%), respectively. The proportion of spontaneous movement in our study was significantly lower than that in previous studies (p = 0.013), with no significant difference in spontaneous respiration (p = 0.097). Following our center's anesthesia protocol during cerebral aneurysm clipping resulted in a low incidence of spontaneous respiration and movement, indicating its safety for patients undergoing intraoperative MEP monitoring.

Intraoperative Hypotension Prediction Based on Features Automatically Generated Within an Interpretable Deep Learning Model.

The monitoring of arterial blood pressure (ABP) in anesthetized patients is crucial for preventing hypotension, which can lead to adverse clinical outcomes. Several efforts have been devoted to develop artificial intelligence-based hypotension prediction indices. However, the use of such indices is limited because they may not provide a compelling interpretation of the association between the predictors and hypotension. Herein, an interpretable deep learning model is developed that forecasts hypotension occurrence 10 min before a given 90-s ABP record. Internal and external validations of the model performance show the area under the receiver operating characteristic curves of 0.9145 and 0.9035, respectively. Furthermore, the hypotension prediction mechanism can be physiologically interpreted using the predictors automatically generated from the proposed model for representing ABP trends. Finally, the applicability of a deep learning model with high accuracy is demonstrated, thus providing an interpretation of the association between ABP trends and hypotension in clinical practice.

Left ventricular remodeling in end-stage liver disease and post-transplant mortality assessed using end-diastolic pressure-volume relation analysis: Observational retrospective study.

BACKGROUND: Diastolic dysfunction is regarded as an important predictor of outcome after liver transplantation (LT). We investigated the influence of liver disease severity on left ventricular diastolic properties using end-diastolic pressure-volume relationship (EDPVR) analysis in patients with end-stage liver disease (ESLD). Association between alterations of the EDPVR and mortality after LT was evaluated. METHODS: In this observational retrospective cohort study, 3,211 patients who underwent LT for ESLD were included in analysis. Variables derived from single-beat EDPVR (diastolic stiffness-coefficient [ß] and end-diastolic volume at an end-diastolic pressure of 20 mmHg [EDVI20] indicating ventricular capacitance) were estimated using preoperative echocardiographic data. Alterations in EDPVR with increased stiffness (ß > 6.16) were categorized into 3 groups; leftward-shifted (EDVI20 <51 mL/m2), rightward-shifted (EDVI20 > 69.7 mL/m2), and intermediate (EDVI20 51-69.7 mL/m2). RESULTS: As the model for ESLD score increases, both EDVI20 and ß gradually increased, which indicated ventricular remodeling with larger capacitance and higher diastolic stiffness. Among patients with increased stiffness (ß > 6.16, n = 1,090), survival rates after LT were lower in leftward-shifted EDPVR than in rightward-shifted EDPVR (73.7% vs 82.9%; log-rank P = 0.002). In the adjusted Cox proportional hazard model, risk of cumulative all-cause mortality at 11 years was the highest in leftward-shifted EDPVR (hazard ratio [HR]: 1.93; 95% confidence interval [CI]: 1.27-2.92), followed by intermediate EDPVR (HR: 1.55; 95% CI: 1.12-2.26), compared with rightward-shifted EDPVR. The SHapley Additive exPlanation model revealed that the variables associated with leftward-shifted EDPVR were diabetes, female sex, old age, and hypertension. CONCLUSIONS: As ESLD advances, diastolic ventricular properties are characterized by increased EDVI20 and ß on rightward-shifted EDPVR, indicating larger capacitance and higher stiffness. However, leftward-shifted EDPVR with left ventricle remodeling failure is associated with poor post-LT survival.

An interactive and realistic phantom for cricothyroidotomy simulation of a patient with obesity through a reusable design using 3D-printing and Arduino.

BACKGROUND AND OBJECTIVES: Proper airway management during emergencies can prevent serious complications. However, cricothyroidotomy is challenging in patients with obesity. Since this technique is not performed frequently but at a critical time, the opportunity for trainees is rare. Simulators for these procedures are also lacking. Therefore, we proposed a realistic and interactive cricothyroidotomy simulator. METHODS: All anatomical structures were modeled based on computed tomography images of a patient with obesity. To mimic the feeling of incision during cricothyroidotomy, the incision site was modeled to distinguish between the skin and fat. To reinforce the educational purpose, capacitive touch sensors were attached to the artery, vein, and thyroid to generate audio feedback. The tensile strength of the silicone-cast skin was measured to verify the similarity of the mechanical properties between humans and our model. The fabrication and assembly accuracies of the phantom between the Standard Tessellation Language and the fabricated model were evaluated. Audio feedback through sensing the anatomy parts and utilization was evaluated. RESULTS: The body, skull, clavicle, artery, vein, and thyroid were fabricated using fused deposition modeling (FDM) with polylactic acid. A skin mold was fabricated using FDM with thermoplastic polyurethane. A fat mold was fabricated using stereolithography apparatus (SLA) with a clear resin. The airway and tongue were fabricated using SLA with an elastic resin. The tensile strength of the skin using silicone with and without polyester mesh was 2.63 ± 0.68 and 2.46 ± 0.21 MPa. The measurement errors for fabricating and assembling parts of the phantom between the STL and the fabricated models were -0.08 ± 0.19 mm and 0.13 ± 0.64 mm. The measurement errors internal anatomy embodied surfaces in fat part were 0.41 ± 0.89 mm. Audio feedback was generated 100% in all the areas tested. The realism, understanding of clinical skills, and intention to retrain were 7.1, 8.8, and 8.3 average points. CONCLUSIONS: Our simulator can provide a realistic simulation experience for trainees through a realistic feeling of incision and audio feedback, which can be used for actual clinical education.

Treatment strategy of Unruptured Intracranial Aneurysms in Octogenarian Patients: A Single-institution Experience.

AIM: The prevalence of octogenarian patients with unruptured intracranial aneurysms (UIAs) has been on the rise. Our objective is to share our clinical insights into octogenarian patients with UIAs and evaluate the treatment strategies for this demographic. MATERIAL AND METHODS: A retrospective analysis was conducted on data from 134 patients with a follow-up exceeding 6 months, all enrolled in this study. We assessed the incidence rates (IRs) of aneurysm growth and rupture, along with potential predictors of aneurysm growth. RESULTS: Among the 134 patients, 99 (73.9%) underwent conservative management, 25 (18.7%) received coiling, and 10 (7.5%) underwent clipping. The mean age of the cohort was 81.8 years. The middle cerebral artery was the most common location for aneurysms. The mean aneurysm size was 4.9 mm, with sizes significantly larger in the treatment groups (coiling and clipping) compared to the observation group (4.4 mm in the observation group; 5.9 and 7.4 mm in the coiling and clipping groups, respectively). The proportion of aneurysms with a daughter sac was higher in the treatment groups compared to the observation group (6.1% vs. 44% [coiling] and 50% [clipping]). The IR of aneurysm growth was 5.9 per 100 person-years, and that of aneurysm rupture was 0.8 per 100 person-years. No factors were statistically significant for aneurysm growth. CONCLUSION: Age alone, especially in individuals over 80 years old, may not be a contraindication for UIA treatment. We recommend considering treatment in octogenarians with high-risk aneurysm features, such as a large aneurysm and the presence of a daughter sac, as the complication rates are low.

Association between red blood cell distribution width and mortality in patients with metastatic brain tumors: A retrospective single-center cohort study.

Metastatic brain tumor has been associated with high mortality and poor prognosis. However, information on indicators predicting surgical prognosis in patients with brain metastases is limited. This study aimed to investigate the association between preoperative red blood cell distribution width (RDW) and mortality in patients who underwent surgery for metastatic brain tumors. This study analyzed 282 patients who underwent metastatic brain tumor surgery between August 1999 and March 2020. Patients were divided into two groups based on preoperative RDW cut-off values (<13.2 and ≥13.2). The surgical outcomes were compared between the two groups. Additionally, we performed Cox regression analysis to assess the association between preoperative RDW and 1-year and overall mortality. There were significant differences in 180-day mortality (6.2% vs. 28.7%, P<0.001), 1-year mortality (23.8% vs. 46.7%, P<0.001), and overall mortality (75.0% vs. 87.7%, P=0.012) between the two groups. In the Cox regression analysis, RDW ≥ 13.2 was significantly associated with higher 1-year mortality (adjusted hazard ratio [HR], 2.14; 95% confidence interval [CI], 1.38-3.30; P<0.001) and overall mortality (HR, 1.44; 95% CI, 1.09-1.90; P=0.010). Preoperative RDW is strongly associated with high mortality in metastatic brain tumor surgery.

[Network Meta-analysis of six Chinese patent medicines for replenishing Qi and activating blood in treatment of chronic heart failure].

The efficacy of six commonly used Chinese patent medicines for replenishing Qi and activating blood in the treatment of chronic heart failure was evaluated systematically by network Meta-analysis. Randomized controlled trials(RCTs) about the treatment of chronic heart failure were searched against CNKI, Wanfang, SinoMed, PubMed, and Cochrane library. Network Meta-analysis was performed in Stata 16. A total of 154 RCTs involving 15 620 patients were eventually included. The network Meta-analysis showed that Qili Qiangxin Capsules+conventional western medicine had the highest total effective rate, followed by Tongxinluo Capsules+conventional western medicine, Qishen Yiqi Drop Pills+conventional western medicine, Naoxintong Capsules+conventional western medicine, Shexiang Tongxin Drop Pills+conventional western medicine, Yangxinshi Tablets+conventional western medicine, and conventional western medicine. As for left ventricular ejection fraction(LVEF), Yangxinshi Tablets+conventional western medicine had the highest value, followed by Shexiang Tongxin Drop Pills+conventional western medicine, Qili Qiangxin Capsules+conventional western medicine, Tongxinluo Capsules+conventional western medicine, Qishen Yiqi Drop Pills+conventional western medicine, Naoxintong Capsules+conventional western medicine, and conventional western treatments. As for N-terminal pro-B type natriuretic peptide(NT-proBNP), Qishen Yiqi Drop Pills+conventional western medicine was the most effective treatment, followed by Yangxinshi Tablets+conventional western medicine, Shexiang Tongxin Drop Pills+conventional western medicine, Qili Qiangxin Capsules+conventional western medicine, Tongxinluo Capsules+conventional western medicine, and conventional the most effective treatment was. As for left ventricular end-diastolic diameter(LVEDD), Naoxintong Capsules+conventional western medicine was the best therapy, followed by Tongxinluo Capsules+conventional western medicine, Shexiang Tongxin Drop Pills+conventional western medicine, Yangxinshi Tablets+conventional western medicine, Qili Qiangxin Capsules+conventional western medicine, Qishen Yiqi Drop Pills+conventional western medicine, and conventional western medicine. In summary, the combination of Chinese patent medicines for replenishing Qi and activating blood with western medicines is superior to conventional western medicine alone in the treatment of chronic heart failure. It effectively improves cardiac function indicators such as LVEF, NT-proBNP, and LVEDD, and thus is worthy of popularization in clinical practice. The results of this study provide evidence-based options for the clinical treatment of chronic cardiac failure by combining the Chinese patent medicines for replenishing Qi and activating blood with western medicine.

Pembrolizumab plus azacitidine in patients with chemotherapy refractory metastatic colorectal cancer: a single-arm phase 2 trial and correlative biomarker analysis.

BACKGROUND: DNA mismatch repair proficient (pMMR) metastatic colorectal cancer (mCRC) is not responsive to pembrolizumab monotherapy. DNA methyltransferase inhibitors can promote antitumor immune responses. This clinical trial investigated whether concurrent treatment with azacitidine enhances the antitumor activity of pembrolizumab in mCRC. METHODS: We conducted a phase 2 single-arm trial evaluating activity and tolerability of pembrolizumab plus azacitidine in patients with chemotherapy-refractory mCRC (NCT02260440). Patients received pembrolizumab 200 mg IV on day 1 and azacitidine 100 mg SQ on days 1-5, every 3 weeks. A low fixed dose of azacitidine was chosen in order to reduce the possibility of a direct cytotoxic effect of the drug, since the main focus of this study was to investigate its potential immunomodulatory effect. The primary endpoint of this study was overall response rate (ORR) using RECIST v1.1., and secondary endpoints were progression-free survival (PFS) and overall survival (OS). Tumor tissue was collected pre- and on-treatment for correlative studies. RESULTS: Thirty chemotherapy-refractory patients received a median of three cycles of therapy. One patient achieved partial response (PR), and one patient had stable disease (SD) as best confirmed response. The ORR was 3%, median PFS was 1.9 months, and median OS was 6.3 months. The combination regimen was well-tolerated, and 96% of treatment-related adverse events (TRAEs) were grade 1/2. This trial was terminated prior to the accrual target of 40 patients due to lack of clinical efficacy. DNA methylation on-treatment as compared to pre-treatment decreased genome wide in 10 of 15 patients with paired biopsies and was significantly lower in gene promoter regions after treatment. These promoter demethylated genes represented a higher proportion of upregulated genes, including several immune gene sets, endogenous retroviral elements, and cancer-testis antigens. CD8+ TIL density trended higher on-treatment compared to pre-treatment. Higher CD8+ TIL density at baseline was associated with greater likelihood of benefit from treatment. On-treatment tumor demethylation correlated with the increases in tumor CD8+ TIL density. CONCLUSIONS: The combination of pembrolizumab and azacitidine is safe and tolerable with modest clinical activity in the treatment for chemotherapy-refractory mCRC. Correlative studies suggest that tumor DNA demethylation and immunomodulation occurs. An association between tumor DNA demethylation and tumor-immune modulation suggests immune modulation and may result from treatment with azacitidine. Trial registration ClinicalTrials.gov, NCT02260440. Registered 9 October 2014, https://clinicaltrials.gov/ct2/show/NCT02260440 .

Solitary osteolytic skull metastasis as the only recurrence of advanced gastric cancer: a case report and literature review.

Bone metastases from gastric cancer are very rare, and skull metastases develop in only 11.2% among patients who develop bone metastases from gastric cancer. We report a case of solitary osteolytic skull metastasis as the only recurrence of advanced gastric cancer. A 67-year-old man was referred to us with a two-month history of headache and progressive scalp swelling in the left parietal region. A right hemiparesis developed a week before admission. Thirteen months previously, he had undergone radical total gastrectomy with Roux-en-Y reconstruction. Pathological analysis indicated well-differentiated adenocarcinoma of the gastric cardia (stage IIIA: pT3N2M0). Brain magnetic resonance imaging showed a large skull metastasis in the left parietal region (approximately 65 × 54 mm). An extensive search did not reveal any other tumors. Gross total tumor resection was performed, and the biopsy revealed an adenocarcinoma, suggesting metastasis of the gastric cancer.

Factors Associated with Occurrence of Atelectasis during Sedation for Imaging in Pediatric Patients: A Retrospective Single Center Cohort Study.

Sedation can induce atelectasis which may cause suboptimal image quality. This study aimed to identify factors associated with the occurrence of atelectasis during sedation for imaging in pediatric patients. Patients < 18 years who had undergone whole-body magnetic resonance imaging (MRI) under sedation with propofol or dexmedetomidine were included in this study. The development of atelectasis was visually and quantitatively assessed by coronal short tau inversion recovery images of the thoracic level. Multivariable logistic regression was performed to identify the independent factors associated with the development of atelectasis. Ninety-one patients were included in the analysis. In the multivariable analysis, administration of supplemental oxygen was the only factor significantly associated with the occurrence of atelectasis (adjusted odds ratio, 4.84; 95% confidence interval, 1.48-15.83; p = 0.009). Univariable analysis showed that the use of dexmedetomidine was associated with a lower incidence of atelectasis; however, this could not be verified in the multivariable analysis. Among the pediatric patients who had undergone imaging under sedation, additional oxygen supplementation was the only independent factor associated with atelectasis occurrence. A prospective clinical trial is required to identify the cause-effect relationship between oxygen administration and occurrence of atelectasis during sedation.

MethylSeqDesign: a framework for Methyl-Seq genome-wide power calculation and study design issues.

Bisulfite DNA methylation sequencing (Methyl-Seq) becomes one of the most important technologies to study methylation level difference at a genome-wide scale. Due to the complexity and large scale of methyl-Seq data, power calculation and study design method have not been developed. Here, we propose a "MethylSeqDesign" framework for power calculation and study design of Methyl-Seq experiments by utilizing information from pilot data. Differential methylation analysis is based on a beta-binomial model. Power calculation is achieved using mixture model fitting of p-values from pilot data and a parametric bootstrap procedure. To circumvent the issue of existing tens of millions of methylation sites, we focus on the inference of pre-specified targeted regions. The performance of the method was evaluated with simulations. Two real examples are analyzed to illustrate our method. An R package "MethylSeqDesign" to implement this method is publicly available.

Real-Time Monitoring of Blood Pressure Using Digitalized Pulse Arrival Time Calculation Technology for Prompt Detection of Sudden Hypertensive Episodes During Laryngeal Microsurgery: Retrospective Observational Study.

BACKGROUND: Laryngeal microsurgery (LMS) is often accompanied by a sudden increase in blood pressure (BP) during surgery because of stimulation around the larynx. This sudden change in the hemodynamic status is not immediately reflected in a casual cuff-type measurement that takes intermittent readings every 3 to 5 min. OBJECTIVE: This study aimed to investigate the potential of pulse arrival time (PAT) as a marker for a BP surge, which usually occurs in patients undergoing LMS. METHODS: Intermittent measurements of BP and electrocardiogram (ECG) and photoplethysmogram (PPG) signals were recorded during LMS. PAT was defined as the interval between the R-peak on the ECG and the maximum slope on the PPG. Mean PAT values before and after BP increase were compared. PPG-related parameters and the correlations between changes in these variables were calculated. RESULTS: BP surged because of laryngoscopic manipulation (mean systolic BP [SBP] from 115.3, SD 21.4 mmHg, to 159.9, SD 25.2 mmHg; P<.001), whereas PAT decreased significantly (from mean 460.6, SD 51.9 ms, to 405.8, SD 50.1 ms; P<.001) in most of the cases. The change in SBP showed a significant correlation with the inverse of the PAT (r=0.582; P<.001). Receiver-operating characteristic curve analysis indicated that an increase of 11.5% in the inverse of the PAT could detect a 40% increase in SBP, and the area under the curve was 0.814. CONCLUSIONS: During LMS, where invasive arterial catheterization is not always possible, PAT shows good correlation with SBP and may, therefore, have the potential to identify abrupt BP surges during laryngoscopic manipulations in a noninvasive manner.

Intramuscular dexmedetomidine and oral chloral hydrate for pediatric sedation for electroencephalography: A propensity score-matched analysis.

BACKGROUND: Intramuscular dexmedetomidine can be used for pediatric sedation without requiring intravenous access and has advantages for electroencephalography by inducing natural sleep pathway, but only a limited number of studies compared the efficacy of intramuscular dexmedetomidine with oral chloral hydrate. AIMS: To compare the efficacy and safety of intramuscular dexmedetomidine and oral chloral hydrate used for sedation during electroencephalography in pediatric patients. METHODS: We reviewed the medical records of pediatric patients who underwent sedation for electroencephalography between January 2015 and December 2016. Initial doses of dexmedetomidine and chloral hydrate were 3 mcg/kg and 50 mg/kg, respectively; second doses (1 mcg/kg and 50 mg/kg, respectively) were administered if adequate sedation was not achieved. Demographic data, time of sedative administration, time of sedation and awakening, and time of arrival at recovery room and discharge were analyzed. RESULTS: Out of a total of 1239 patients, 125 patients had received dexmedetomidine and 1114 had received chloral hydrate. After 1:1 propensity score matching, the dexmedetomidine and chloral hydrate groups each had 118 patients. Testing completion rate with a single dose of medication was higher in the dexmedetomidine group (91.5% vs 71.2%; mean difference [95% CI] 20.3 [10.8-29.9]; P < .0001; Pearson chi-square value = 16.09). Sedation onset time was shorter in the dexmedetomidine group as well (16.6 ± 13.0 minutes vs 41.5 ± 26.8 minutes; mean difference [95% CI] 24.8 [19.1-30.6]; P < .0001; T = 8.27). On the contrary, the duration of recovery was longer in the dexmedetomidine group (35.5 ± 40.2 minutes vs 18.5 ± 30.7 minutes; mean difference [95% CI] 18.6 [8.8-28.5]; P = .0002; T = -2.82). Total residence time was not significantly different between the two groups (125.8 ± 40.6 minutes vs 122.1 ± 42.2 minutes, mean difference [95% CI] 5.21 [6.1-16.5], P = .3665 T = 0.04). CONCLUSIONS: Intramuscular dexmedetomidine showed higher sedation success rate and shorter time to achieving the desired sedation level compared with oral chloral hydrate and thus may be an effective alternative for oral chloral hydrate in pediatric patients requiring sedation for electroencephalography.

P-value evaluation, variability index and biomarker categorization for adaptively weighted Fisher's meta-analysis method in omics applications.

MOTIVATION: Meta-analysis methods have been widely used to combine results from multiple clinical or genomic studies to increase statistical powers and ensure robust and accurate conclusions. The adaptively weighted Fisher's method (AW-Fisher), initially developed for omics applications but applicable for general meta-analysis, is an effective approach to combine P-values from K independent studies and to provide better biological interpretability by characterizing which studies contribute to the meta-analysis. Currently, AW-Fisher suffers from the lack of fast P-value computation and variability estimate of AW weights. When the number of studies K is large, the 3K - 1 possible differential expression pattern categories generated by AW-Fisher can become intractable. In this paper, we develop an importance sampling scheme with spline interpolation to increase the accuracy and speed of the P-value calculation. We also apply bootstrapping to construct a variability index for the AW-Fisher weight estimator and a co-membership matrix to categorize (cluster) differentially expressed genes based on their meta-patterns for intuitive biological investigations. RESULTS: The superior performance of the proposed methods is shown in simulations as well as two real omics meta-analysis applications to demonstrate its insightful biological findings. AVAILABILITY AND IMPLEMENTATION: An R package AWFisher (calling C++) is available at Bioconductor and GitHub (https://github.com/Caleb-Huo/AWFisher), and all datasets and programing codes for this paper are available in the Supplementary Material. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Appraisal of Cardiac Ejection Fraction With Liver Disease Severity: Implication in Post-Liver Transplantation Mortality.

BACKGROUND AND AIMS: Enhanced sympathetic nervous activation and peripheral vasodilation in end-stage liver disease (ESLD) may limit the importance of left ventricular ejection fraction (LVEF) as an influential prognosticator. We sought to understand the LVEF and cardiac dimensions in ESLD patients in order to define the LVEF threshold to predict all-cause mortality after liver transplantation (LT). APPROACH AND RESULTS: Data were collected prospectively from the Asan LT Registry between 2008 and 2016, and outcomes were retrospectively reviewed. LVEF, end-diastolic volume index (EDVI), and end-diastolic elastance (Eed) were measured by preoperative echocardiography. Of 2,799 patients, 452 (16.2%) had LVEF ≤ 60%, with 29 (1.0%) having LVEF < 55% and 269 (9.6%) had LVEF ≥ 70%. Over a median of 5.4-year follow-up, 329 (11.8%) patients died: 104 (3.7%) died within 90 days. LVEF (range, 30%-81%) was directly proportionate to Model for End-stage Liver Disease (MELD) scores, an index of liver disease severity, in survivors but showed a fixed flat-line pattern in nonsurvivors (interaction P = 0.004 between groups), with lower EDVI (P = 0.013) and higher Eed (P = 0.001) in the MELD ≥ 20 group. Patients with LVEF ≤ 60% had higher 90-day (13% vs. 7.4%; log rank, P = 0.03) and median 5.4-year (26.7% vs. 16.2%; log rank, P = 0.003) mortality rates in the MELD ≥ 20 group, respectively, compared to those with LVEF > 60%. Specifically, in the MELD > 35 group, median 5.4-year mortality rate was 53.3% in patients with LVEF ≤ 60% versus 24% in those with LVEF > 60% (log rank P < 0.001). By contrast, mortality rates of LVEF ≤ 60% and > 60% were similar in the MELD < 20 group (log rank P = 0.817). CONCLUSIONS: LVEF ≤ 60% is strongly associated with higher post-LT mortality rates in the MELD ≥ 20 group, indicating the need to appraise both LVEF and liver disease severity simultaneously. Enhanced diastolic elastance with low EDVI provides insights into pathogenesis of low LVEF in nonsurvivors with MELD ≥ 20.