Longitudinal Function Research Articles

Longitudinal strain correlates with 6-minute walk distance whereas ejection fraction and diastolic parameters do not

BackgroundImpaired functional capacity is a common symptom in patients with heart failure. Standard measures of left ventricular (LV) function, such as ejection fraction (EF) and LV diastolic parameters, do not correlate with measures of functional capacity. The aim of this study is to determine if measures of global and regional LV strain better correlate with 6-minute walk distance than does EF or measures of LV diastolic function.Methods120 patients referred to a cardiology clinic for evaluation of known or suspected heart failure were approached for enrollment. Of those 120 patients, 58 had an echocardiogram within 3 months of enrollment with images adequate for regional and global strain assessment, had no contra-indication to exercise testing, and had no previously documented non-cardiac explanation for dyspnea on exertion. In those 58 patients, 6-minute walk distance was measured, LV EF was determined with Simpson’s biplane method, and global and regional longitudinal strain were measured with TomTec Image Arena 4.5.1 software.ResultsLV EF had no correlation with 6-minute walk distance (r = 0.22, p = 0.09) even when controlling for age, gender, and BMI (p = 0.07). No measures of LV diastolic function (including E velocity, Deceleration Time, e’ annular velocities, or E/e’) had a correlation with 6-minute walk distance. Multiple measures of global and regional LV longitudinal systolic function had a correlation with 6-minute walk distance. Longitudinal strain of the basal LV segments had the strongest correlation with 6-minute walk distance (r= -0.36, p = 0.005), and correlation persisted after controlling for age, gender, BMI, and systolic blood pressure (p = 0.004).ConclusionsLongitudinal strain correlates with a measure of functional capacity, but LVEF and traditional measures of LV diastolic dysfunction do not. Measures of longitudinal strain, especially in basal LV segments, will likely be an important marker of clinically relevant LV function.Graphical

Cardiac function, haemodynamics, and valve competence with exercise in patients with heart failure with preserved ejection fraction and mild to moderate secondary mitral regurgitation.

This study aimed to evaluate the clinical significance of secondary mitral regurgitation (MR) in patients with heart failure with preserved ejection fraction (HFpEF). We conducted a prospective study enrolling consecutively evaluated patients with HFpEF undergoing invasive haemodynamic exercise testing with simultaneous echocardiography. Compared to HFpEF without MR (n = 145, 79.7%), those with mild or moderate MR (n = 37, 20.3%) were older, more likely to be women, had more left ventricular (LV) systolic dysfunction, and more likely to have left atrial (LA) myopathy reflected by greater burden of atrial fibrillation, more LA dilatation, and poorer LA function. Pulmonary artery (PA) wedge pressure was higher at rest in HFpEF with MR (17 ± 5 mmHg vs. 20 ± 5 mmHg, p = 0.005), but there was no difference with exercise. At rest, only 2 (1.1%) patients had moderate MR, and none developed severe MR. Pulmonary vascular resistance was higher, and right ventricular (RV)-PA coupling was more impaired in patients with HFpEF and MR at rest and exercise. LV and LA myocardial dysfunction remained more severe in patients with MR during stress compared to those without MR, characterized by greater LA dilatation during all stages of exertion, lower LA emptying fraction and compliance, steeper and rightward-shifted LA pressure-volume relationships, and reduced LV longitudinal contractile function. Patients with HFpEF and mild or moderate MR have more severe LV systolic dysfunction, LA myopathy, RV-PA uncoupling, and more severe pulmonary vascular disease. Mitral valve incompetence in this setting is a phenotypic marker of more advanced disease but is not a causal factor in development of HFpEF.

Quantifying fetal heart health in gestational diabetes: a new approach with fetal heart quantification technology.

This study aimed to assess the impact of gestational diabetes mellitus (GDM) on fetal heart structure and function using a technique called fetal heart quantification (Fetal HQ), with a focus on mitochondrial dynamics, which employs advanced imaging technology for comprehensive analysis. A total of 180 fetuses with normal heart structures, aged 24-40weeks of gestation, were examined. A 2-3s cine loop in the standard four-chamber oblique view was captured and analyzed using the speckle-tracking technique with Fetal HQ. Various echocardiographic parameters were evaluated, including four-chamber view (4CV), global spherical index (GSI), global longitudinal strain (GLS), 24-segment spherical index (SI), ventricular fractional area change (FAC), cardiac output (CO), and stroke volume (SV). These parameters were compared between the GDM group and the control group during two gestational periods: 24+0 to 28+0 weeks and 28+1 to 40+1 weeks. Statistical analysis was performed using independent samples t-tests and Mann-Whitney U tests to identify significant differences. Twenty fetuses from mothers with GDM and 40 from the control group were recruited at 24+0 to 28+0 weeks. At 28+1 to 40+1 weeks, 40 fetuses from mothers with GDM and 80 from the control group were recruited. The fetal left ventricular global longitudinal function was similar between the GDM and control groups. However, compared to the controls, right ventricular function in the GDM group was lower only at 28+1 to 40+1 weeks. In the GDM group, the global spherical index (GSI) was lower than in the control group at 28+1 to 40+1 weeks (1.175 vs. 1.22; p = 0.001). There were significant decreases in ventricular FAC (38.74% vs. 42.83%; p < 0.0001) and 4CV GLS for the right ventricle (-22.27% vs. -26.31%; p = 0.005) at 28+1 to 40+1 weeks. Our findings suggest that GDM is associated with decreased right ventricular function in the fetal heart, particularly during the later stages of pregnancy (28+1 to 40+1 weeks), compared to fetuses from healthy pregnancies. The Fetal HQ technique represents a valuable tool for evaluating the structure and function of fetal hearts affected by GDM during the advanced stages of pregnancy.

LV systolic function assessment in conventional cardiac pacing: a simple and forgotten parameter - MAPSE

Abstract Background Mitral annular plane systolic excursion (MAPSE) was a widely used M-mode echocardiographic marker of left ventricular longitudinal systolic function. On the other hand, right ventricle (RV) apical pacing is associated with left ventricle (LV) dysfunction development due to dysynchronous activation, while non-apical pacing may provide a more physiological LV activation. The aim of this study is to ascertain the clinical usefulness of MAPSE in the assessment of LV contractile function in patients with permanent RV pacing. Methods Consecutive patients with indication for permanent cardiac pacing (with ventricular pacing percentages over 20% - Vp&amp;gt;20%) were retrospectively enrolled from 2019 to 2023. All patients were assessed by echocardiography with MAPSE, left ventricule ejection fraction (LVEF) and diastolic filling patterns being measured at the time of implant and at subsequent follow-ups. Results 359 patients (age range 41-80yo; mean age=60,5yo) were included, 244 men and 115 women, 173 implanted with single-chamber devices and 186 dual-chamber. 259 patients were paced from the RVA (right ventricle apex) and 62 had septal lead positioning. The mean follow-up period was 18±2 months. The results showed that a MAPSE cut off value of ≤10 mm was associated with a LVEF&amp;lt;42±2%, while MAPSE values &amp;gt;10mm were associated with LVEF&amp;gt;45±3% (p&amp;lt;0.01). RV septal pacing was associated with a higher average MAPSE value (14,28 mm) than RVA pacing (13,47). Conclusions MAPSE seems to corelate well with LVEF in RV conventional pacing. Younger patients with preserved LVEF and less than grade II diastolic dysfunction were not associated with a significant decrese in MAPSE value. However, older patients with HFmrEF and RVA pacing seem to have a more substantial reduction in MAPSE value, suggesting that non-apical or conduction system pacing might be beneficial in this subgroup. MAPSE seems to be a quick and reliable echocardiographic marker of LV systolic function in patients with permanent cardiac pacing. It may be used as an early predictive marker for heart failure in conventional RV paced patients.

Decoupling of the structure functions in momentum space based on the Laplace transformation

Using Laplace transform techniques, we describe the determination of the longitudinal structure function FL(x,Q2), at the leading-order approximation in momentum space, from the structure function F2(x,Q2) and its derivative with respect to lnQ2 in a kinematical region of low values of the Bjorken variable x. Since the x dependence of F2(x,Q2) and its evolution with Q2 are determined much better by the data than FL(x,Q2), this method provides both a direct check on FL(x,Q2) where measured, and a way of extending FL(x,Q2) into regions of x and Q2 where there are currently no data. In our calculations, we ultilize the Block-Durand-Ha parametrization for the structure function F2(x,Q2) [M. M. Block , .]. We find that the Laplace transform method in momentum space provides correct behaviors of the extracted longitudinal structure function FL(x,Q2) and that our obtained results are in line with data from the H1 Collaboration and other results for FL(x,Q2) obtained using Mellin transform method. Published by the American Physical Society 2024

Left Ventricular Longitudinal Myocardial Function of Heart Failure Patients With Transition From Reduced to Preserved Ejection Fraction and of Those With Preserved Ejection Fraction.

Background: Left ventricular (LV) longitudinal myocardial function is associated with the outcomes of heart failure (HF) patients. HF with improved ejection fraction (EF), known as HFimpEF, which is defined as current LVEF >40% but any previously documented LVEF ≤40%, has favorable outcomes compared with HF with preserved EF (HFpEF). However, LV longitudinal myocardial function in patients with previously reduced LVEF (<50%) but improved LVEF to within the normal range (≥50%) (HFnorEF) and its association with cardiovascular events remain unclear. Methods and Results: We studied 70 patients with HFpEF and 65 with HFnorEF. LV longitudinal myocardial function was assessed as global longitudinal strain (GLS). The primary endpoint was defined as cardiovascular death or HF hospitalization during follow-up of 5.6±3.1 years. The GLS of HFpEF patients was significantly lower than that of HFnorEF patients (13.6±3.5% vs. 14.8±2.2%, P=0.02) even when the LVEF was similar. Multivariate Cox proportional hazards analysis showed that GLS was independently associated with cardiovascular events. Furthermore, of the entire study population, patients with GLS >15.0% had fewer cardiovascular events than those without (log-rank P=0.014) among all the patients. Conclusions: LV longitudinal myocardial dysfunction was more frequently observed in patients with HFpEF than in those with HFnorEF, even when LVEF was similar, and was independently associated with cardiovascular events for HF patients with current LVEF ≥50%.

Echocardiographic evaluation of ventricular performance in VA-ECMO weaning: results from a observational multicentric prospective study

Abstract Funding Acknowledgements None. Background Although temporary mechanical circulatory support devices are increasingly used in the management of cardiogenic shock (CS), several open question regarding the kind of support and timing of institution/weaning remains open. Echocardiography is widely applied to drive the weaning process from VA-ECMO although there are no standardized protocols. Purpose We sought to evaluate the accuracy of echocardiographic indices in predicting successful weaning from VA-ECMO in CS patients. We tested total isovolumic time (tIVT), an index of ventricular performance(1,2), and longitudinal function (MAPSE) on top of the commonly used parameters (left ventricular ejection fraction, LVEF; E/e’ at mitral valve; left ventricular velocity time integral, LV VTI; TAPSE; right ventricular S’ at tissue Doppler imaging, RV S’). Methods Multicentric prospective study on adults receiving VA-ECMO due to refractory CS and/or cardiac arrest (CA) from 2012 to 2020. Echocardiography was performed at VA-ECMO placement and during the weaning trials. Waning trials were performed daily starting from 48 hours after VA-ECMO institution. A stepwise decrease of VA-ECMO blood flow was applied, until reaching 1 or 1.5 L/min. Successful weaning was defined as removal of VA-ECMO with no requirement for further MCS in the following 30 days. Results 76 patients were enrolled (23.8% female, 54.2±10.6 years-old), 52.6% due to CA. Median duration of VA-ECMO was 58 hours; 47 (61.8%) had intra-aortic balloon pump (IABP) inserted upfront. In-hospital mortality was 62.4% overall, 40% for CS without CA. 6 of the 32 weaned patients died in hospital for multiorgan failure due to septic shock. The baseline echocardiographic parameters associated with successful weaning were (Figure 1-A): stroke volume (SV) &amp;gt;13.2 ml (HR 4.12 [1.71-9.95], p 0.002), tIVT &amp;gt;23.6 min/sec (HR 0.14 [0.02-1.03], p 0.053), LV VTI &amp;gt;6.6 cm (HR 4.99 [1.94-12.87], p&amp;lt;0.001), MAPSE &amp;gt;6.15 mm (HR 4.42 [1.90-10.24], p 0.001), TAPSE &amp;gt;11 mm (HR 10.13 [1.37-7.02], p 0.023), RV S’ &amp;gt;7 cm (HR 5.40 [1.45-20.12], p 0.012). LVEF, E/e’ and S’ at mitral valve did not reach the statistical significance. Figure 1-B shows Kaplan-Meier analysis on echocardiographic indices collected during the last weaning trial; figure 2 details HR of all these parameters. Conclusions Echocardiography is pivotal in defining cardiac recovery and monitoring the weaning trial. Indices reflecting ventricular performance and delivered flow from LV were associated with weaning success both at VA-ECMO institution and throughout the weaning trials. Parameters reflecting ventricular activation and systo-diastolic interaction already demonstrated superiority in defining ventricular performance. Considering the known limitations of LVEF (HR, loading and LV dyssynchrony dependence), tIVT and MAPSE should be introduced in the standard evaluation in the acute setting.

Cardiac Mechanics Evaluation in Preschool-Aged Children with Preterm Birth History: A Speckle Tracking and 4D Echocardiography Study.

Background: The premature-born adult population is set to grow significantly, and prematurity has emerged as an important cardiovascular risk factor. We aimed to comprehensively assess cardiac mechanics and function in a cohort of ex-preterm preschoolers. Methods: Ex-preterm children (<30 weeks of gestation), aged 2 to 5 years, underwent transthoracic 2D, speckle-tracking, and 4D echocardiography. The findings were compared with 19 full-term children. Results: Our cohort of 38 children with prematurity history showed a normal morpho-functional echocardiographic assessment. However, compared to controls, the indexed 3D end-diastolic volumes of ventricular chambers were reduced (left ventricle 58.7 ± 11.2 vs. 67.2 ± 8.5 mL/m2; right ventricle 50.3 ± 10.4 vs. 57.7 ± 11 mL/m2; p = 0.02). Left ventricle global and longitudinal systolic function were worse in terms of fraction shortening (32.9% ± 6.8 vs. 36.5% ± 5.4; p = 0.05), ejection fraction (59.2% ± 4.3 vs. 62.3% ± 3.7; p = 0.003), and global longitudinal strain (-23.6% ± 2.4 vs. -25.5% ± 1.7; p = 0.003). Finally, we found a reduced left atrial strain (47.4% ± 9.7 vs. 54.9% ± 6.8; p = 0.004). Conclusions: Preschool-aged ex-preterm children exhibited smaller ventricles and subclinical impairment of left ventricle systolic and diastolic function compared to term children. Long-term follow-up is warranted to track the evolution of these findings.

Left and right ventricular longitudinal systolic function following aortic valve replacement in the PARTNER 2 trial and registry.

Evaluation of left and right ventricular (RV) longitudinal systolic function may enhance risk stratification following aortic valve replacement (AVR). The study objective was to evaluate the changes in left and RV longitudinal systolic function and RV-pulmonary artery (RV-PA) coupling from baseline to 30 days and 1 year after AVR. Left ventricular (LV) longitudinal strain (LS), tricuspid annulus plane systolic excursion (TAPSE), and RV-PA coupling were evaluated in patients from the PARTNER 2A surgical AVR (SAVR) arm (n = 985) and from the PARTNER 2 SAPIEN 3 registry (n = 719). TAPSE and RV-PA coupling decreased significantly following SAVR, but remained stable following TAVR. Lower LV LS, TAPSE, or RV-PA coupling at baseline was associated with increased risk of the composite of death, hospitalization, and stroke at 5 years [adjusted hazard ratios (HRs) for LV LS < 15%: 1.24, 95% confidence interval (CI) 1.05-1.45, P = 0.001; TAPSE < 14 mm: 1.44, 95% CI 1.21-1.73, P < 0.001; RV-PA coupling < 0.55 mm/mmHg: 1.32, 95% CI 1.07-1.63, P = 0.011]. Reduced TAPSE at baseline was the most powerful predictor of the composite endpoint at 5 years. Patients with LV ejection fraction <50% at baseline had increased risk of the primary endpoint with SAVR (HR: 1.34, 95% CI 1.08-1.68, P = 0.009) but not with TAVR (HR: 1.12, 95% CI 0.88-1.42). Lower RV-PA coupling at 30 days showed the strongest association with cardiac mortality. SAVR but not TAVR was associated with a marked deterioration in RV longitudinal systolic function and RV-PA coupling. Lower TAPSE and RV-PA coupling at 30 days were associated with inferior clinical outcomes at 5 years. In patients with LVEF < 50%, TAVR was associated with superior 5-year outcomes.

Proton PDFs with nonlinear corrections from gluon recombination

We present numerical studies of the leading nonlinear corrections to the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi evolution equations of parton distribution functions (PDFs) resulting from gluon recombination. The effect of these corrections is to reduce the pace of evolution at small momentum fractions x while slightly increasing it at intermediate x. By implementing the nonlinear evolution in the framework, we have carried out fits of proton PDFs using data on lepton-proton deep inelastic scattering from HERA, BCDMS, and NMC. While we find no evidence for the presence of nonlinearities, they cannot be entirely excluded either, and we are able to set limits for their strength. In terms of the recombination scale Qr, which plays a similar role as the saturation scale in the dipole picture of the proton, we find that Qr≲2.5 GeV. We also quantify the impact of the nonlinear terms for the longitudinal structure function at the Electron-Ion Collider and the Large Hadron Electron Collider and find that these measurements could provide stronger constraints on the projected effects. Published by the American Physical Society 2024

Mitral Annulus Pre-Systolic Excursion (MAPSE) Versus Modified Simpson’s Method for Ejection Fraction Estimation in Patients with Acute Coronary Syndrome

Objectives: Evaluating left ventricle (LV) systolic function is pivotal in cardiac assessment, primarily relying on the left ventricular ejection fraction (LVEF) calculated through the modified Simpson’s method. However, challenges arise in accurately determining LVEF, especially in patients with acute coronary syndrome, where difficulty in visualizing the blood tissue interface can lead to inaccuracies. Mitral annular plane systolic excursion (MAPSE), which evaluates longitudinal function of LV has shown promise in detecting subtle myocardial abnormalities, particularly in patients with preserved ejection fraction (EF). Materials and Methods: The study included three groups of patients based on EF measurement using modified Simpson’s method: Group A with EF &lt;50%, Group B with EF &gt;50%, and Group C as healthy controls. In each group, MAPSE and EF derived from MAPSE formula were calculated: 4.8 × MAPSE (mm) + 5.8 in males, 4.2 × MAPSE (mm) + 2.0 in females. Statistical analyses were conducted to assess the agreement and potential differences between the two methods within each group. Results: The mean age of study population was 55.63 ± 9.21 years in Group A, 54.79 ± 9.82 years in Group B, and 55.10 ± 8.79 years in Group C. In Group A, mean EF measured through modified Simpson’s formula was 37.79 ± 5.38, whereas mean EF measured through MAPSE was 37.95 ± 5.32. There was no statistical difference among EF calculation through Simpson’s method or MAPSE method. (P = 0.8293). In Group B, Mean EF calculated through Simpson method was 56.24 ± 3.12 whereas with MAPSE method was 52.31 ± 4.26. There was found to be a statistical difference in EF calculation by both of this method in patients with EF&gt;50% (P &lt; 0.0001). In Group C, mean EF calculated through Simpson’s method was 64.23 ± 5.21 and through MAPSE was 64.99 ± 4.85, respectively. There was no statistical difference between this two methods in terms of EF calculation (P = 0.2812). Conclusion: EF assessment using the traditional modified Simpson’s method and MAPSE demonstrated a strong correlation in patients with EF &lt;50% and controls. However, in patients with EF &gt;50%, MAPSE revealed subendocardial dysfunction undetected by the Simpson method, highlighting MAPSE’s value in identifying subtle myocardial abnormalities.

Characteristics and determinants of pulmonary long COVID.

BACKGROUNDPersistent cough and dyspnea are prominent features of postacute sequelae of SARS-CoV-2 (also termed "long COVID"); however, physiologic measures and clinical features associated with these pulmonary symptoms remain poorly defined. Using longitudinal pulmonary function testing (PFT) and CT imaging, this study aimed to identify the characteristics and determinants of pulmonary long COVID.METHODSThis single-center retrospective study included 1,097 patients with clinically defined long COVID characterized by persistent pulmonary symptoms (dyspnea, cough, and chest discomfort) lasting for 1 or more months after resolution of primary COVID infection.RESULTSAfter exclusion, a total of 929 patients with post-COVID pulmonary symptoms and PFTs were stratified as diffusion impairment and pulmonary restriction, as measured by percentage predicted diffusion capacity for carbon monoxide (DLCO) and total lung capacity (TLC). Longitudinal evaluation revealed diffusion impairment (DLCO ≤ 80%) and pulmonary restriction (TLC ≤ 80%) in 51% of the cohort overall (n = 479). In multivariable modeling regression analysis, invasive mechanical ventilation during primary infection conferred the greatest increased odds of developing pulmonary long COVID with diffusion impairment and restriction (adjusted odds ratio [aOR] = 9.89, 95% CI 3.62-26.9]). Finally, a subanalysis of CT imaging identified radiographic evidence of fibrosis in this patient population.CONCLUSIONLongitudinal PFTs revealed persistent diffusion-impaired restriction as a key feature of pulmonary long COVID. These results emphasize the importance of incorporating PFTs into routine clinical practice for evaluation of long COVID patients with prolonged pulmonary symptoms. Subsequent clinical trials should leverage combined symptomatic and quantitative PFT measurements for more targeted enrollment of pulmonary long COVID patients.FUNDINGNational Institute of Allergy and Infectious Diseases (AI156898, K08AI129705), National Heart, Lung, and Blood Institute (HL153113, OTA21-015E, HL149944), and the COVID-19 Urgent Research Response Fund at the University of Alabama at Birmingham.

Departure from the statistical equilibrium of large scales in forced three-dimensional homogeneous isotropic turbulence

We study the statistically steady states of the forced dissipative three-dimensional homogeneous isotropic turbulence at scales larger than the forcing scale in real separation space. The probability density functions (p.d.f.s) of longitudinal velocity difference at large separations are close to, but deviate from, Gaussian, measured by their non-zero odd parts. The analytical expressions of the third-order longitudinal structure functions derived from the Kármán–Howarth–Monin equation prove that the odd-part p.d.f.s of velocity differences at large separations are small but non-zero. Specifically, when the forcing effect in the displacement space decays exponentially as the displacement tends to infinity, the odd-order longitudinal structure functions have a power-law decay with an exponent of $-$ 2, implying a significant coupling between large and small scales. Under the assumption that forcing controls the large-scale dynamics, we propose a conjugate regime to Kolmogorov's inertial range, independent of the forcing scale, to capture the odd parts of p.d.f.s. Thus, dynamics of large scales departs from the absolute equilibrium, and we can partially recover small-scale information without explicitly resolving small-scale dynamics. The departure from the statistical equilibrium is quantified and found to be viscosity-independent. Even though this departure is small, it is significant and should be considered when studying the large scales of the forced three-dimensional homogeneous isotropic turbulence.

Longitudinal Upper Extremity Function in FSHD Monitored by Portable 3D Motion Capture Analyses (P3-11.006)

Longitudinal Upper Extremity Function in FSHD Monitored by Portable 3D Motion Capture Analyses (P3-11.006)

Significant improvements in the olfactory sensitivity of bipolar I disorder patients during euthymia versus manic episodes: a longitudinal study.

Research has indicated that individuals diagnosed with bipolar disorder (BD) might experience alterations in their olfaction or levels of serum tumor necrosis factor-α (TNF-α), but no studies have investigated olfactory function and serum TNF-α in BD patients simultaneously. Moreover, there is a lack of existing research that compares the longitudinal olfactory function between individuals with manic and euthymic BD I. Patients with manic BD I (BDM, n=44) and healthy controls (HCs, n=32) were evaluated symptoms (measured via the Young Manic Rating Scale, YRMS), social function (measured via the Global Assessment Function, GAF), serum TNF-α, and olfactory function (via the Sniffin' Sticks test) including olfactory sensitivity (OS) and olfactory identification (OI). The BDM patients were followed up to the remission period and re-evaluated again. We compared OS, OI and serum TNF-α in manic and euthymic patients with BD I and HCs. We examined the correlation between olfactory function and symptoms, social function, and serum TNF-α in patients with BD I. The BDM patients exhibited significantly lower OS and OI compared to the HCs (Z = -2.235, P = 0.025; t = -6.005, P < 0.001), while a positive correlation was observed between OS and GAF score (r = 0.313, P = 0.039). The OS in the BD I remission group (n=25) exhibited significantly superior performance compared to the BDM group (t = -4.056, P < 0.001), and the same as that in the HCs (P = 0.503). The change in OS showed a positive correlation with the decrease in YMRS score (r = 0.445, P = 0.026), and a negative correlation with the course of disease (r = -0.594, P = 0.002). The TNF-α in BD I patients was significantly lower compared to HCs (P < 0.001), and not significantly correlated with olfactory function (all P > 0.05). The findings suggest that OS and OI are impaired in BDM patients, and the impaired OS in those patients can be recovered in the remission stage. OI may serve as a potential characteristic marker of BD. OS might be useful as an index for BDM treatment efficacy and prognosis.

Universal relative scaling of longitudinal structure functions in shear-dominated turbulence

Shear significantly influences turbulence in the energy-containing range of shear-dominated flows, and the longitudinal structure functions do not have a universal form as they do in homogeneous isotropic turbulence. Despite this, the relative scaling of structure functions exhibits universal sub-Gaussian behaviour in shear-dominated flows, in particular for turbulent boundary layers, channels and Taylor–Couette flows. Our investigation of a turbulent vertical buoyancy layer at $Pr = 0.71$ using direct numerical simulation shows this universality even in moderate-Reynolds-number buoyancy-driven but shear-dominated boundary layers. It is demonstrated that the universality is related to the energy density of the eddies, which attains a hierarchical equilibrium in the energy-containing range of shear-dominated turbulence. We conjecture that the universal sub-Gaussian behaviour of the energy density of the energy-containing range, which was considered to be non-trivial in prior studies, is related to the universal anomalous scaling exponents of the inertial subrange turbulence. Based on this conjecture, we propose a hypothesis that relates large-scale eddies and the intermittent dissipation field in shear-dominated turbulence, highlighting a relationship between large and small scales. A phenomenological model is also developed to predict the scaling, which is verified using data from a turbulent boundary layer, half-channel and vertical buoyancy layer at friction Reynolds numbers spanning four orders of magnitude. Excellent agreement is observed.

A2/A2B to B kidney transplantation outcomes: A single center 7-year experience.

Data on long-term outcomes following A2/A2B to B kidney transplants since the 2014 kidney allocation system (KAS) changes are few. The primary aim of this study is to report our 7-year experience with A2/A2B to B kidney transplants and to compare post-transplant outcomes of A2/A2B to a concurrent group of B to B kidney transplants. Additionally, the study evaluates the impact of pre-transplant anti-A1 titers on survival outcomes in A2/A2B transplants. This retrospective, single-center analysis included all adults who received A2/A2B to B deceased donor kidney transplants from December 2014 to June 2021 compared to B to B recipients. The effects of pre-transplant IgM/IgG titers, stratified as ≤1:8 and ≥1:16, on death-censored, rejection-free, and overall graft survival were tested. Fifty-three A2/A2B and 114 B to B adults were included with a median follow-up time of 32 months. Overall graft survival, patient survival, and rejection-free graft survival did not differ between the two groups. There were no differences between the groups' overall kidney function values (p>.80) or their temporal trajectories (time by group interaction p>.11). Unadjusted death-censored graft survival was lower in A2/A2B to B compared to B recipients (p=.03), but the effect was not significant (p=.195) after adjusting for any readmissions (p=.96), rejection episodes (p<.001) or BK infection (p=.76). We did not detect an effect of pre-transplant titer group on death-censored (p=.59), rejection-free (p=.61), or overall graft survival (p=.26) CONCLUSIONS: A2/A2B to B kidney transplants have comparable overall patient and graft survival, rejection-free graft survival, and longitudinal renal function compared to B to B transplants at our center. Allograft survival outcomes were not significantly different between patients with low and high pre-transplant anti-A1 IgM/IgG titers.

Myelin Oligodendrocyte Glycoprotein Antibody Disease Optic Neuritis: A Structure-Function Paradox?

Myelin oligodendrocyte glycoprotein antibody disease (MOGAD) is a demyelinating disorder that most commonly presents with optic neuritis (ON) and affects children more often than adults. We report 8 pediatric patients with MOG-associated ON and characterize focal optical coherence tomography (OCT) abnormalities over time that help distinguish this condition from the trajectories of other demyelinating disorders. These OCT findings are examined in the context of longitudinal visual function testing. This is a retrospective case series of 8 pediatric patients with MOG-associated ON who were referred for neuro-ophthalmic evaluation. Longitudinal data for demographics, clinical history, physical examination, and OCT obtained in the course of clinical evaluations were collected through retrospective medical record review. Patients demonstrated acute peripapillary retinal nerve fiber layer (RNFL) thickening in one or both eyes, consistent with optic disc swelling. This was followed by steady patterns of average RNFL thinning, with 9 of 16 eyes reaching significantly low RNFL thickness using OCT platform reference databases ( P < 0.01), accompanied by paradoxical recovery of high-contrast visual acuity (HCVA) in every patient. There was no correlation between HCVA and any OCT measures, although contrast sensitivity (CS) was associated with global thickness, PMB thickness, and nasal/temporal (N/T) ratio, and color vision was associated with PMB thickness. There was a lower global and papillomacular bundle (PMB) thickness ( P < 0.01) in clinically affected eyes compared with unaffected eyes. There was also a significantly higher N:T ratio in clinically affected eyes compared with unaffected eyes in the acute MOG-ON setting ( P = 0.03), but not in the long-term setting. MOG shows a pattern of prominent retinal atrophy, as demonstrated by global RNFL thinning, with remarkable preservation of HCVA but remaining deficits in CS and color vision. These tests may be better clinical markers of vision changes secondary to MOG-ON. Of the OCT parameters measured, PMB thickness demonstrated the most consistent correlation between structural and functional measures. Thus, it may be a more sensitive marker of clinically significant retinal atrophy in MOG-ON. The N:T ratio in acute clinically affected MOG-ON eyes in our study was higher than the N:T ratio of neuromyelitis optica (NMO)-ON eyes and similar to the N:T ratio in multiple sclerosis (MS)-ON eyes as presented in the prior literature. Therefore, MOG may share a more similar pathophysiology to MS compared with NMO.

Peristaltic mechanism of Ellis fluid with viscous dissipation and thermal radiation induced by cilia wave

Bioheat transfer analysis in tissue has attracted the attention of numerous researchers due to its widespread potential applications in the medical field, mainly in thermotherapy and the human thermoregulation system. Also, temperature regulation of the human body primarily occurs through bioheat transfer. Due to the widespread biomedical applications of bio-heat transfer, we aim to investigate the movement of biofluid and bioheat in human organs with the influences of thermal radiation and ciliary waves. The mathematical model for Ellis fluid flow through a tube includes the metachronal wave of cilia motion and convective conditions. The governing equations are created based on mass, momentum conservation, and energy. The current problem is displayed and exact solutions are managed under long wavelength [Formula: see text] and low Reynolds number [Formula: see text] approximations. An analytical approach is employed to derive expressions for longitudinal velocity, temperature, pressure gradient, and stream function as a function of the parameters of the problem. The physical behavior of the peristaltic motion of the Ellis fluid is explained in detail and illustrated graphically for various parameter values. The results of the current study provide potential information for advancement in the biomedical industry, particularly in the development of biomedical devices and processes.

Differential Cognitive Effects of Unilateral Subthalamic Nucleus Deep Brain Stimulation for Parkinson's Disease.

The aim of this study was to investigate the cognitive effects of unilateral directional versus ring subthalamic nucleus deep brain stimulation (STN DBS) in patients with advanced Parkinson's disease. We examined 31 participants who underwent unilateral STN DBS (left n = 17; right n = 14) as part of an National Institutes of Health (NIH)-sponsored randomized, double-blind, crossover study contrasting directional versus ring stimulation. All participants received unilateral DBS implants in the hemisphere more severely affected by motor parkinsonism. Measures of cognition included verbal fluency, auditory-verbal memory, and response inhibition. We used mixed linear models to contrast the effects of directional versus ring stimulation and implant hemisphere on longitudinal cognitive function. Crossover analyses showed no evidence for group-level changes in cognitive performance related to directional versus ring stimulation. Implant hemisphere, however, impacted cognition in several ways. Left STN participants had lower baseline verbal fluency than patients with right implants (t [20.66 = -2.50, p = 0.02]). Verbal fluency declined after left (p = 0.013) but increased after right STN DBS (p < 0.001), and response inhibition was faster following right STN DBS (p = 0.031). Regardless of hemisphere, delayed recall declined modestly over time versus baseline (p = 0.001), and immediate recall was unchanged. Directional versus ring STN DBS did not differentially affect cognition. Similar to prior bilateral DBS studies, unilateral left stimulation worsened verbal fluency performance. In contrast, unilateral right STN surgery increased performance on verbal fluency and response inhibition tasks. Our findings raise the hypothesis that unilateral right STN DBS in selected patients with predominant right brain motor parkinsonism could mitigate declines in verbal fluency associated with the bilateral intervention. ANN NEUROL 2024;95:1205-1219.