MultiClassMetabo: A Superior Classification Model Constructed Using Metabolic Markers in Multiclass Metabolomics.

Multiclass metabolomics has become a popular technique for revealing the mechanisms underlying certain physiological processes, different tumor types, or different therapeutic responses. In multiclass metabolomics, it is highly important to uncover the underlying biological information on biosamples by identifying the metabolic markers with the most associations and classifying the different sample classes. The classification problem of multiclass metabolomics is more difficult than that of the binary problem. To date, various methods exist for constructing classification models and identifying metabolic markers consisting of well-established techniques and newly emerging machine learning algorithms. However, how to construct a superior classification model using these methods remains unclear for a given multiclass metabolomic data set. Herein, MultiClassMetabo has been developed for constructing a superior classification model using metabolic markers identified in multiclass metabolomics. MultiClassMetabo can enable online services, including (a) identifying metabolic markers by marker identification methods, (b) constructing classification models by classification methods, and (c) performing a comprehensive assessment from multiple perspectives to construct a superior classification model for multiclass metabolomics. In summary, MultiClassMetabo is distinguished for its capability to construct a superior classification model using the most appropriate method through a comprehensive assessment, which makes it an important complement to other available tools in multiclass metabolomics. MultiClassMetabo can be accessed at http://idrblab.cn/multiclassmetabo/.

Attosecond ionic photoionization spectroscopy.

Photoionization is one of the most fundamental processes in light-matter interaction. Advanced attosecond photoelectron spectroscopy provides the possibility to characterize the ultrafast photoemission process in an extremely short attosecond time scale. Following scattering symmetry rules, residual ions encode ultrafast photoionization prints at the instant of electron removal forming an alternative electron emission chronoscope. Here, we experimentally illustrate the attosecond ion reconstruction of attosecond beating by interference of two-photon transition (RABBIT)-like interferometry through the development of high-resolution ion momentum detection in atomic photoionization processes. Our ion interferometry presents identical momentum- and time-dependent scattering phase shift, as we observed in photoelectron spectroscopy, and thus demonstrates that ion interferometry can be a possible alternative attosecond approach to resolve the photoionization process, without the electron homogeneity limitation.

deepAFT: A nonlinear accelerated failure time model with artificial neural network.

The Cox regression model or accelerated failure time regression models are often used for describing the relationship between survival outcomes and potential explanatory variables. These models assume the studied covariates are connected to the survival time or its distribution or their transformations through a function of a linear regression form. In this article, we propose nonparametric, nonlinear algorithms (deepAFT methods) based on deep artificial neural networks to model survival outcome data in the broad distribution family of accelerated failure time models. The proposed methods predict survival outcomes directly and tackle the problem of censoring via an imputation algorithm as well as re-weighting and transformation techniques based on the inverse probabilities of censoring. Through extensive simulation studies, we confirm that the proposed deepAFT methods achieve accurate predictions. They outperform the existing regression models in prediction accuracy, while being flexible and robust in modeling covariate effects of various nonlinear forms. Their prediction performance is comparable to other established deep learning methods such as deepSurv and random survival forest methods. Even though the direct output is the expected survival time, the proposed AFT methods also provide predictions for distributional functions such as the cumulative hazard and survival functions without additional learning efforts. For situations where the popular Cox regression model may not be appropriate, the deepAFT methods provide useful and effective alternatives, as shown in simulations, and demonstrated in applications to a lymphoma clinical trial study.

The impact of proactive versus reactive drug monitoring of infliximab on treatment outcomes in patients with crohn's disease.

BACKGROUND: Therapeutic drug monitoring (TDM) plays a crucial role in the management of Crohn's disease (CD) patients receiving infliximab (IFX). While reactive TDM has been more commonly utilized previously, recent research suggests that proactive TDM may offer greater benefits for patients. OBJECTIVE: To compare treatment outcomes among patients receiving different monitoring modalities of IFX. METHODS: This was a retrospective cohort study that enrolled 142 CD patients who initiated IFX therapy at the First Affiliated Hospital of Nanjing Medical University from January 2014 to June 2021. The patients were divided into a reactive (n = 43) and proactive (n = 99) group. The outcome measures included sustained clinical response and remission rates, biological remission rates, endoscopic response and remission rates achieved in both groups at weeks 30 and 54. The incidence of adverse events (AEs), changes in IFX trough concentrations (TCs) and treatment adjustments within 54 weeks were also evaluated. RESULTS: Kaplan-Meier analysis demonstrated that the proactive group exhibited significantly higher cumulative probabilities of sustained clinical response, sustained clinical remission, and endoscopic response by Week 54. Compared to the reactive group, patients in the proactive group achieved significantly reduced rates of AEs-related hospitalization and surgery. After adjusting treatment strategies, the median concentration and the proportion of patients achieved an effective therapeutic concentration (TC > 3 µg/mL) at Week 54 was both significantly higher in the proactive group. CONCLUSIONS: Proactive TDM of IFX plays a more crucial role in timely adjustment of treatment strategies and maintenance of effective concentrations, thereby contributing to the outcomes for CD patients.

Myeloid-derived growth factor suppresses VSMC dedifferentiation and attenuates postinjury neointimal formation in rats by activating S1PR2 and its downstream signaling.

Restenosis after angioplasty is caused usually by neointima formation characterized by aberrant vascular smooth muscle cell (VSMC) dedifferentiation. Myeloid-derived growth factor (MYDGF), secreted from bone marrow-derived monocytes and macrophages, has been found to have cardioprotective effects. In this study we investigated the effect of MYDGF to postinjury neointimal formation and the underlying mechanisms. Rat carotid arteries balloon-injured model was established. We found that plasma MYDGF content and the level of MYDGF in injured arteries were significantly decreased after balloon injury. Local application of exogenous MYDGF (50 µg/mL) around the injured vessel during balloon injury markedly ameliorated the development of neointimal formation evidenced by relieving the narrow endovascular diameter, improving hemodynamics, and reducing collagen deposition. In addition, local application of MYDGF inhibited VSMC dedifferentiation, which was proved by reversing the elevated levels of osteopontin (OPN) protein and decreased levels of α-smooth muscle actin (α-SMA) in the left carotid arteries. We showed that PDGF-BB (30 ng/mL) stimulated VSMC proliferation, migration and dedifferentiation in vitro; pretreatment with MYDGF (50-200 ng/mL) concentration-dependently eliminated PDGF-BB-induced cell proliferation, migration and dedifferentiation. Molecular docking revealed that MYDGF had the potential to bind with sphingosine-1-phosphate receptor 2 (S1PR2), which was confirmed by SPR assay and Co-IP analysis. Pretreatment with CCG-1423 (Rho signaling inhibitor), JTE-013 (S1PR2 antagonist) or Ripasudil (ROCK inhibitor) circumvented the inhibitory effects of MYDGF on VSMC phenotypic switching through inhibiting S1PR2 or its downstream RhoA-actin monomers (G-actin) /actin filaments (F-actin)-MRTF-A signaling. In summary, this study proves that MYDGF relieves neointimal formation of carotid arteries in response to balloon injury in rats, and suppresses VSMC dedifferentiation induced by PDGF-BB via S1PR2-RhoA-G/F-actin-MRTF-A signaling pathway. In addition, our results provide evidence for cross talk between bone marrow and vasculature.

Cyclosporine A alleviates colitis by inhibiting the formation of neutrophil extracellular traps via the regulating pentose phosphate pathway.

BACKGROUND: The aberrant formation of neutrophil extracellular traps (NETs) has been implicated in ulcerative colitis (UC), a chronic recurrent intestinal inflammation. Cyclosporine A (CsA) is now applied as rescue therapy for acute severe UC. In addition, it has been certained that CsA inhibits the formation of NETs in vitro and the mechanism of which was still vague. The study aimed to explore the mechanism CsA inhibits the NETs formation of colitis in vivo and in vitro. METHODS: NETs enrichment in clinical samples was analyzed using databases from Gene Expression Omnibus and verified in our center. Dextran sulfate sodium (DSS)-induced acute colitis mice model was used to investigate the effect of CsA on NETs of colonic tissue expression. To clarify the mechanism, intracellular energy metabolites were examined by Liquid Chromatograph Mass Spectrometer, and reactive oxygen species (ROS) levels were examined by fluorescence intensity in neutrophils treated with CsA after LPS stimulation. The transcriptional level and activity of G6PD of neutrophils were also assessed using qRT-PCR and WST-8. RNA Sequencing was used to detect differentially expressed genes of neutrophils stimulated by LPS with or without CsA. The expression levels of related proteins were detected by western blot. RESULTS: NETs enrichment was especially elevated in moderate-to-severe UC patients compared to HC. NETs expression in the colon from DSS colitis was decreased after CsA treatment. Compared with neutrophils stimulated by LPS, NETs formation and cellular ROS levels were decreased in LPS + CsA group. Cellular ribulose 5-phosphate and NADPH/NADP + related to the pentose phosphate pathway (PPP) were reduced in LPS + CsA group. In addition, CsA could decrease G6PD activity in neutrophils stimulated with LPS, and the results were further verified by inhibiting G6PD activity. At last, P53 protein was highly expressed in LPS + CsA group compared with the LPS group. Intracellular G6PD activity, ROS level and NETs formation, which were downregulated by CsA, could be reversed by a P53 inhibitor. CONCLUSION: Our results indicated CsA could alleviate the severity of colitis by decreasing the formation of NETs in vivo. In vitro, CsA reduced ROS-dependent NETs release via downregulating PPP and cellular ROS levels by decreasing G6PD activity directly by activating the P53 protein.

Identifying photoelectron releasing order in strong-field dissociative ionization of H2.

Driven by intense laser fields, the outgoing photoelectrons in molecules possess a quiver motion, resulting in the rise of the effective ionization potential. The coupling of the field-dressed ionization potential with abundant molecular dynamics complicates the laser-molecule interactions. Here, we demonstrate an approach to resolve photoelectron releasing order in the dissociative and non-dissociative channels of multiphoton ionization driven by an orthogonally polarized two-color femtosecond laser pulse. The photoelectron kinetic energy releases and the regular nodes in the photoelectron angular distributions due to the participation of different continuum partial waves allow us to deduce the field-dressed ionization potential of various channels. It returns the ponderomotive energy experienced by the outgoing electron and reveals the corresponding photoionization instants within the laser pulse. Our results provide a route to explore the complex strong-field ionization dynamics of molecules using two-dimensional photoelectron momentum spectroscopy.

Enhancing Strong-Field Dissociation of H_{2}

We investigate the above-threshold multiphoton ionization of H_{2} embedded in superfluid He nanodroplets driven by ultraviolet femtosecond laser pulses. We find that the surrounding He atoms enhance the dissociation of in-droplet H_{2}^{+} from lower vibrational states as compared to that of isolated gas-phase molecules. As a result, the discrete peaks in the photoelectron energy spectrum correlated with the HHe^{+} from the dissociative in-droplet molecule shift to higher energies. Based on the electron-nuclear correlation, the photoelectrons with higher energies are correlated to the nuclei of the low-vibrationally excited molecular ion as the nuclei share less photon energy. Our time-dependent nuclear wave packet quantum simulation using a simplified He-H_{2}^{+} system confirms the joint contribution of the driving laser field and the neighboring He atoms to the dissociation dynamics of the solute molecular ion. The results strengthen our understanding of the role of the environment on light-induced ultrafast dynamics of molecules.

Resolving Quantum Interference Black Box through Attosecond Photoionization Spectroscopy.

Multiphoton light-matter interactions invoke a so-called "black box" in which the experimental observations contain the quantum interference between multiple pathways. Here, we employ polarization-controlled attosecond photoelectron metrology with a partial wave manipulator to deduce the pathway interference within this quantum 'black box" for the two-photon ionization of neon atoms. The angle-dependent and attosecond time-resolved photoelectron spectra are measured across a broad energy range. Two-photon phase shifts for each partial wave are reconstructed through the comprehensive analysis of these photoelectron spectra. We resolve the quantum interference between the degenerate p→d→p and p→s→p two-photon ionization pathways, in agreement with our theoretical simulations. Our approach thus provides an attosecond time-resolved microscope to look inside the "black box" of pathway interference in ultrafast dynamics of atoms, molecules, and condensed matter.

A nonparametric simultaneous confidence band for biomarker effect on the restricted mean survival time.

Study of prognostic and predictive biomarkers plays an important role in the design and analysis of clinical trials. The Cox proportional hazards model is often used to study the biomarker main effect and the treatment-biomarker interaction effect for survival data. The estimated effects can be biased if the proportional hazards assumption is violated. The restricted mean survival time is becoming popular in clinical studies for having a clear intuitive interpretation. In this article, we first propose nonparametric methods to make statistical inference for the one-sample problem of the biomarker effect on the restricted mean survival time; we then extend the methods to the two-sample problem for studying the difference in the biomarker effects between treatment groups in clinical trials. For a given biomarker, the restricted mean survival time is estimated by kernel smoothing methods with the inverse probability of censoring weights. We prove the consistency for the estimates and develop simultaneous confidence bands for the biomarker effects on the restricted mean survival time. The simultaneous confidence bands are evaluated in extensive simulation studies and are found to have good finite sample performance. We then apply the proposed methods to a breast cancer study conducted by the Breast International Group (BIG) to illustrate how the Ki67 biomarker, a protein marker of cell proliferation, affects the survival time of patients, compared between the treatment groups.

External validation and comparison of simple ultrasound activity score and international bowel ultrasound segmental activity score for Crohn's disease.

BACKGROUND: Intestinal ultrasound (IUS) is a non-invasive tool for monitoring Crohn's disease (CD) activity. Recently, sonographic activity scores, including the International Bowel Ultrasound Segmental Activity Score (IBUS-SAS) and Simple Ultrasound Activity Score for CD (SUS-CD), were developed. This study aimed to assess their clinical application value. METHODS: This retrospective study enrolled patients with CD from March 2021 to June 2022. The diagnostic performance of the ultrasound scores was evaluated using the simplified endoscopic score for CD (SES-CD). Correlations of ultrasound scores with SES-CD, CD activity index (CDAI), and inflammatory biomarkers were assessed. Inter-rater reliability was compared. RESULTS: In total, 140 patients were included. The IBUS-SAS for evaluating disease activity had an area under the curve (AUC) of 0.895, sensitivity of 85.4%, and specificity of 82.4% for the cut-off value of 48.7. The SUS-CD revealed an AUC of 0.835, sensitivity of 92.7%, and specificity of 64.7% for the cut-off value of 2.5. The IBUS-SAS and SUS-CD were positively correlated with SES-CD (r = 0.511 and 0.534, respectively). The scores correlated significantly with the CDAI and inflammatory biomarkers (all p < 0.01). The IBUS-SAS was more strongly correlated with CDAI (r = 0.666 vs 0.486) and C-reactive protein (r = 0.645 vs 0.434) than the SUS-CD. The intraclass correlation coefficient (ICC) of the IBUS-SAS and SUS-CD between the two sonologists was excellent (ICC = 0.96 and 0.78, respectively). CONCLUSION: Both the IBUS-SAS and SUS-CD can evaluate disease activity in CD and exhibited a significant correlation with activity indices and inflammatory biomarkers. CLINICAL TRIAL REGISTRATION: ChiCTR2200055221.

Mean platelet volume may predict all-cause and cardiovascular mortality among incident peritoneal dialysis patients.

BACKGROUND: The association between mean platelet volume (MPV) and mortality in patients with cardiovascular disease has been demonstrated. However, the association between MPV and mortality in peritoneal dialysis (PD) patients remains unclear. METHODS: Patients catheterized at the First Affiliated Hospital, Nanchang University, between November 1, 2005, and August 31, 2019, were enrolled. The primary endpoints were all-cause and cardiovascular mortality. Patients were divided into two groups according to the cutoff value, which was determined using maximally selected rank statistics. The mortality hazard ratio was evaluated using Cox regression models. RESULTS: Among the 1322 PD patients enrolled, the mean age was 49.3 ± 14.5 years, 57.6% were men, and 18.8% had diabetes. During a median follow-up of 50 months (IQR: 30-80), 360 patients died; among these, 167 deaths were attributed to cardiovascular diseases. Survival analysis revealed that all-cause and cardiovascular mortality rates were lower in the higher-MPV group than in the lower-MPV group (p < .001 and p < .001, respectively). After full adjustment, a higher MPV was significantly associated with a hazard ratio of 0.77 for all-cause mortality (95% CI: 0.60-0.98, p = .036) and 0.75 for cardiovascular mortality (95% CI: 0.51-0.97, p = .041). Subgroup analysis showed that a significant interaction existed between age and MPV (p < .001). Decreased MPV was associated with higher mortality risk only in patients < 60 years old. CONCLUSIONS: Our results showed that lower MPV can be associated with a higher risk of all-cause and cardiovascular mortality in patients with PD.

The Impact of Perioperative Use of Nonbiologic Disease-Modifying Anti-rheumatic Drugs on Perioperative Blood Loss and Complications in Patients Who Have Rheumatoid Arthritis Undergoing Total Knee Arthroplasty.

BACKGROUND: The use of disease-modifying antirheumatic drugs (DMARDs) before total knee arthroplasty (TKA) was associated with increased risk of postoperative periprosthetic joint and wound infections as well as worse platelet function in patients who have knee rheumatoid arthritis (RA). This study investigated the effects of DMARDS on perioperative blood loss, complications, and blood transfusion in patients undergoing TKA for knee RA. METHODS: We retrospectively enrolled patients undergoing TKA for knee RA at our hospital between 2017 and 2021 who received DMARDs (n = 73) or not (n = 84). Every RA patient was matched with patients who had osteoarthritis (OA) in a ratio of 1:1 or 1:2. Primary outcomes were intraoperative and perioperative blood losses, while secondary outcomes were complications and allogeneic transfusions. RESULTS: The mean total (804 versus 728 mL (mL), P = .114), mean intraoperative (113 versus 101 mL, P = .488), or hidden blood losses (705 versus 640 mL, P = .340) did not differ statistically between RA patients who received DMARDs versus those who did not. RA patients who received DMARDs showed significantly greater mean total (804 versus 654 mL, P = .001), intraoperative (113 versus 75 mL, P = .002), and hidden blood losses (705 versus 560 mL, P = .016) than OA patients. No statistical differences were found in complications or allogeneic transfusions. CONCLUSION: Although RA patients experienced greater perioperative blood loss than OA patients, there was no statistical difference in perioperative blood loss, complications, or allogeneic transfusions between RA patients who received DMARDs and those who did not.

More complications and higher transfusion rate in patients with rheumatoid arthritis than osteoarthritis undergoing total hip arthroplasty.

PURPOSE: Total hip arthroplasty (THA) in patients with rheumatoid arthritis (RA) has been associated with an increased risk of periprosthetic joint infection, periprosthetic fractures, dislocations, and post-operative blood transfusion. However, higher post-operative blood transfusion is unclear whether it reflects peri-operative blood loss or is characteristic of RA. This study aimed to compare the complications, allogenic blood transfusion, albumin use, and peri-operative blood loss between patients who underwent THA because of RA or osteoarthritis (OA). METHODS: Patients undergoing cementless THA for hip RA (n = 220) or hip OA (n = 261) at our hospital between 2011 and 2021 were retrospectively enrolled. Deep vein thrombosis, pulmonary embolism, myocardial infarction, calf muscular venous thrombosis, wound complications, deep prosthetic infection, hip prosthesis dislocation, periprosthetic fractures, 30-day mortality, 90-day readmission, allogeneic blood transfusion, and albumin infusions were considered as primary outcomes, while secondary outcomes included the number of perioperative anaemia patients as well as total, intra-operative, and hidden blood loss. RESULTS: Compared to the OA group, patients with hip RA showed significantly higher rates of wound aseptic complications, hip prosthesis dislocation, homologous transfusion, and albumin use. RA patients also showed a significantly higher prevalence of pre-operative anemia. However, no significant differences were observed between the two groups in total, intra-operative, or hidden blood loss. CONCLUSIONS: Our study suggests that RA patients undergoing THA are at a higher risk of wound aseptic complications and hip prosthesis dislocation than patients with hip OA. Pre-operative anaemia and hypoalbuminaemia in patients with hip RA place them at a significantly higher risk of post-operative blood transfusion and use of albumin.

A Communication Anti-Jamming Scheme Assisted by RIS with Angular Response.

By optimizing the reconfigurable intelligent surface (RIS) reflection coefficients, the channel capacity of legitimate users can be increased, thereby enhancing the anti-jamming performance of communication systems. However, existing studies on RIS-assisted anti-jamming assume that there is no coupling between the RIS reflection coefficients and the incident angle of electromagnetic (EM) waves, which is quite unreasonable. Therefore, we consider the effect of the incident angle of EM waves on the reflection coefficients of the RIS and propose a communication anti-jamming scheme assisted by an RIS with angular response. Specifically, a problem is formulated to optimize the RIS reflection coefficients so that the legitimate signal is amplified, but the jamming signal is attenuated, thus enhancing the legitimate channel capacity. However, the coupling of the EM incident angle and the RIS reflection coefficients causes the problem to be non-convex. To tackle this problem, we equivalently transform the RIS reflection coefficients optimization problem into a quadratically constrained quadratic programming (QCQP) problem using the complex Taylor expansion and the multidimensional complex quadratic transform (MCQT) and solve it utilizing the alternating direction method of the multipliers (ADMM) algorithm. The simulation results reveal that, compared to other schemes supported by RIS without angular response, the proposed scheme is able to achieve a significant improvement in the anti-jamming performance.

Tourniquets can further reduce perioperative blood loss in patients on dexamethasone and tranexamic acid during cemented total knee arthritis: a single-center, double-blind, randomized controlled trial.

BACKGROUND: Multiple doses of dexamethasone and tranexamic acid can inhibit postoperative inflammation and reduce fibrinolysis and perioperative blood loss in total knee arthroplasty. In this single-center, double-blind, randomized clinical trial, the aim was to investigate whether applying a tourniquet to patients on dexamethasone and tranexamic acid could further reduce perioperative blood loss. MATERIALS AND METHODS: Patients who underwent cemented total knee arthroplasty at our hospital were randomized to receive a tourniquet (n = 71) or not (n = 70) during the procedure. All patients received multiple doses of dexamethasone and tranexamic acid perioperatively. The primary outcome was perioperative blood loss, while secondary outcomes were surgery duration, postoperative laboratory indices of inflammation and fibrinolysis, range of knee motion, VAS pain score, knee circumference, knee swelling rate, homologous transfusion, albumin use, and complications. RESULTS: Using a tourniquet was associated with significantly lower intraoperative blood loss (P < 0.001) and total blood loss (P = 0.007) as well as significantly shorter surgery duration (P < 0.001). In contrast, the tourniquet did not significantly affect hidden blood loss, postoperative inflammation or fibrinolysis, range of knee motion, VAS pain score, knee circumference, knee swelling rate, homologous transfusion, albumin use, or complications. CONCLUSIONS: The results of this randomized clinical trial demonstrate that applying a tourniquet during cemented total knee arthroplasty to patients receiving multiple doses of dexamethasone and tranexamic acid can further reduce perioperative blood loss without increasing the risk of inflammation, fibrinolysis, or other complications. Thus, it is advised to use tourniquets combined with dexamethasone and tranexamic acid to reduce perioperative blood loss and avoid tourniquet-related adverse events. LEVEL OF EVIDENCE: Therapeutic Level I. Trial registration Chinese Clinical Trail Registry, ChiCTR2200060567. Registered 5 June 2022-retrospectively registered, http://www.chictr.org.cn/showproj.aspx?proj=171291.

Probing Resonant Photoionization Time Delay by Self-Referenced Molecular Attoclock.

Attosecond time-resolved electron tunneling dynamics have been investigated by using attosecond angular streaking spectroscopy, where a clock reference to the laser field vector is required in atomic strong-field ionization and the situation becomes complicated in molecules. Here we reveal a resonant ionization process via a transient state by developing an electron-tunneling-site-resolved molecular attoclock in Ar-Kr^{+}. Two distinct deflection angles are observed in the photoelectron angular distribution in the molecular frame, corresponding to the direct and resonant ionization pathways. We find the electron is temporally trapped in the Coulomb potential wells of the Ar-Kr^{+} before finally releasing into the continuum when the electron tunnels through the internal barrier. By utilizing the direct tunneling ionization as a self-referenced arm of the attoclock, the time delay of the electron trapped in the resonant state is revealed to be 3.50±0.04 fs. Our results give an impetus to exploring the ultrafast electron dynamics in complex systems and also endow a semiclassical presentation of the electron trapping dynamics in a quantum resonant state.

Femtosecond Rotational Dynamics of D_{2} Molecules in Superfluid Helium Nanodroplets.

Rotational dynamics of D_{2} molecules inside helium nanodroplets is induced by a moderately intense femtosecond pump pulse and measured as a function of time by recording the yield of HeD^{+} ions, created through strong-field dissociative ionization with a delayed femtosecond probe pulse. The yield oscillates with a period of 185 fs, reflecting field-free rotational wave packet dynamics, and the oscillation persists for more than 500 periods. Within the experimental uncertainty, the rotational constant B_{He} of the in-droplet D_{2} molecule, determined by Fourier analysis, is the same as B_{gas} for an isolated D_{2} molecule. Our observations show that the D_{2} molecules inside helium nanodroplets essentially rotate as free D_{2} molecules.

Dexamethasone Attenuates the Perioperative Acute Phase Response for Simultaneous Bilateral Total Hip Arthroplasty.

BACKGROUND: This study aimed to evaluate the effect of perioperative dexamethasone on acute phase response (APR) after simultaneous bilateral total hip arthroplasty (SimBTHA). METHODS: A retrospective case-control study was performed on 177 SimBTHA procedures. The patients were divided into 2 cohorts: patients receiving perioperative dexamethasone and patients in whom no dexamethasone was administered. We observed the effects of perioperative dexamethasone on the APR following SimBTHA by trending C-reactive protein and interleukin-6. Besides, the incidence of postoperative nausea and vomiting (PONV), postoperative visual analog scale (VAS) score, use of antiemetic and analgesic rescue, and complications were also compared. RESULTS: Compared to the no dexamethasone group, patients receiving dexamethasone yielded a significantly decreased C-reactive protein on postoperative days 1, 2 and 3. Such differences of interleukin-6 were also detected. In addition, the incidence of PONV, postoperative VAS score, and use of antiemetic and analgesic rescue were significantly decreased without increasing the risk of early surgical wound infection and gastrointestinal hemorrhage in patients receiving dexamethasone. CONCLUSION: The anti-inflammatory effects of dexamethasone can attenuate the APR after SimBTHA as well as decrease the PONV, postoperative VAS score, and use of antiemetic and analgesic rescue.

Poor performance of monocyte-to-lymphocyte ratio, neutrophil-to-lymphocyte ratio, and fibrinogen when screening for occult infection among patients with sequelae of suppurative hip arthritis before total hip arthroplasty.

BACKGROUND: Total hip arthroplasty (THA) is considered the best treatment for sequelae of suppurative hip arthritis, but such patients are more likely to have occult infection and therefore to suffer post-operative periprosthetic joint infection. Our study examined (1) the occult infection rate among patients with sequelae of suppurative hip arthritis, and whether (2) neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), or fibrinogen levels can be used to screen such patients for occult infection before THA. METHODS: We retrospectively enrolled 428 patients who underwent primary THA at our hospital between 2010 and 2021, of whom 31 had occult infection and 397 did not. The maximum sensitivity and specificity were determined for the three indicators using receiver operating characteristic curves, and positive and negative predictive values were calculated. RESULTS: Patients with occult infection showed significantly higher erythrocyte sedimentation rate (ESR) and higher levels of C-reactive protein (CRP) and fibrinogen than those without occult infection. The various potential indicators gave the following areas under the receiver operating characteristic curves: ESR, 0.586; CRP, 0.599; interleukin-6, 0.651; NLR, 0.506; MLR, 0.600; and fibrinogen, 0.589. Sensitivity and specificity were as follows: ESR, 30.8% and 92.5%; CRP, 50.0% and 70.2%; interleukin-6, 57.7% and 67.5%; NLR, 46.7% and 62.9%; MLR, 60.0% and 61.7%; and fibrinogen, 43.3% and 81.7%. CONCLUSION: The rate of occult infection was 7.24% among our patients. ESR, NLR, MLR, and levels of CRP, interleukin-6, and fibrinogen may be unreliable for screening such patients for occult infection before THA according to sensitivity and specificity.