Contraction Pattern Research Articles

Sex differences in deep brain shape and asymmetry persist across schizophrenia and healthy individuals: A meta-analysis from the ENIGMA-Schizophrenia Working Group.

Schizophrenia (SCZ) is characterized by a disconnect from reality that manifests as various clinical and cognitive symptoms, and persistent neurobiological abnormalities. Sex-related differences in clinical presentation imply separate brain substrates. The present study characterized deep brain morphology using shape features to understand the independent effects of diagnosis and sex on the brain, and to determine whether the neurobiology of schizophrenia varies as a function of sex. This study analyzed multi-site archival data from 1,871 male (M) and 955 female (F) participants with SCZ, and 2,158 male and 1,877 female healthy controls (CON) from twenty-three cross-sectional samples from the ENIGMA Schizophrenia Workgroup. Harmonized shape analysis protocols were applied to each site's data for seven deep brain regions obtained from T1-weighted structural MRI scans. Effect sizes were calculated for the following main contrasts: 1) Sex effects;2) Diagnosis-by-Sex interaction; 3) within sex tests of diagnosis; 4) within diagnosis tests of sex differences. Meta-regression models between brain structure and clinical variables were also computed separately in men and women with schizophrenia. Mass univariate meta-analyses revealed more concave-than-convex shape differences in all regions for women relative to men, across diagnostic groups ( d = -0.35 to 0.20, SE = 0.02 to 0.07); there were no significant diagnosis-by-sex interaction effects. Within men and women separately, we identified more-concave-than-convex shape differences for the hippocampus, amygdala, accumbens, and thalamus, with more-convex-than-concave differences in the putamen and pallidum in SCZ ( d = -0.30 to 0.30, SE = 0.03 to 0.10). Within CON and SZ separately, we found more-concave-than-convex shape differences in the thalamus, pallidum, putamen, and amygdala among females compared to males, with mixed findings in the hippocampus and caudate ( d = -0.30 to 0.20, SE = 0.03 to 0.09). Meta-regression models revealed similarly small, but significant relationships, with medication and positive symptoms in both SCZ-M and SCZ-F. Sex-specific variation is an overriding feature of deep brain shape regardless of disease status, underscoring persistent patterns of sex differences observed both within and across diagnostic categories, and highlighting the importance of including it as a critical variable in studies of neurobiology. Future work should continue to explore these dimensions independently to determine whether these patterns of brain morphology extend to other aspects of neurobiology in schizophrenia, potentially uncovering broader implications for diagnosis and treatment. Statistical analyses revealed significant main effects for diagnosis and sex in deep brain shape morphology. Among patients with schizophrenia, there was a pattern of thinning and surface contraction in the bilateral hippocampus, amygdala, accumbens, and thalamus, and a pattern of significant thickening and surface expansion in the bilateral putamen and pallidum compared to healthy control participants. Between males and females, there was a pattern of significant thinning and surface contraction in the bilateral thalamus, pallidum, putamen, and amygdala in females compared to males.There was no significant interaction between diagnosis and biological sex, suggesting that sex differences in deep brain shape and asymmetry among patients with schizophrenia reflect those observed in healthy individuals.Small but statistically significant relationships exist between brain structure and clinical correlates of schizophrenia were similar for both men and women with the disease, such that higher CPZ was associated with shape-derived thinning and surface contraction in the caudate, accumbens, hippocampus, amygdala, and thalamus, and elevated positive symptoms were associated with shape-derived thinning and surface contraction in the bilateral caudate, right hippocampus, and right amygdala.

Premature ventricular contraction patterns associated with nonsustained ventricular tachycardia

BackgroundOccurrence of nonsustained ventricular tachycardia (NSVT) is associated with negative outcomes. It is not clear whether specific electrocardiographic characteristics of premature ventricular contractions (PVCs) are associated with the occurrence of NSVT. The aim of this study was to identify electrocardiographic patterns associated with the presence of NSVT during 24-h electrocardiographic monitoring in patients with >10 PVCs per hour. MethodsThis was a retrospective, observational, cross-sectional study. We reviewed consecutive patients who received 24-h ECG monitoring performed at a single outpatient cardiology center. Patients who received 24-h electrocardiographic monitoring, with a PVC burden ≥10 PVCs/h were included. Occurrence of NSVT during 24-h electrocardiographic monitoring was the main outcome. ResultsA total of 343 patients were analyzed (mean [SD] age, 69.7 [12.5] years; 177 men [51.6 %]). NSVT occurred in 72 patients who were compared with 271 patients without NSVT. The novel term “premature beat ratio”, which aims to correlate the coupling interval and compensatory pause, was introduced; a value >0.5 was independently associated with NSVT according to the multivariate model (OR = 3.73, 95 % CI = 1.57–8.82; P = 0.002). PVC burden (OR = 1.09, 95 % CI = 1.02–1.17; P = 0.006), and triplets (OR = 18.19, 95 % CI = 7.32–45.18 P = 0.0) were also associated with NSVT in the multivariate model. ConclusionThese findings suggest that patients with a high PVC burden, triplets, and a premature beat ratio greater than 0.5 have an increased probability of presenting with NSVT and may benefit from more rigorous follow-up.

Mapping uterine calcium dynamics during the ovulatory cycle in live mice.

Uterine contraction patterns vary during the ovulatory cycle and throughout pregnancy, but prior measurements have produced limited and conflicting information on these patterns. We combined a virally delivered genetically encoded calcium reporter (GCaMP8m) and ultra-widefield imaging in live nonpregnant mice to characterize uterine calcium dynamics at organ scale throughout the estrous cycle. Prior to ovulation (proestrus and estrus), uterine excitations primarily initiated in a region near the oviduct, but after ovulation (metestrus and diestrus), excitations initiated at loci homogeneously distributed throughout the organ. The frequency of excitation events was lowest in proestrus and estrus, higher in metestrus, and highest in diestrus. These results establish a platform for mapping uterine activity and demonstrate that an anatomically localized trigger for uterine excitations depends on the estrous cycle phase.

The Relationship Between Glabellar Contraction Patterns and Glabellar Muscle Anatomy: A Magnetic Resonance Imaging-based Study.

Glabellar contraction patterns were introduced to the scientific literature to help guide glabellar neuromodulator injection algorithms. However, the relationship between the underlying musculature and its influence on these glabellar contraction patterns is unclear. The aim of this study was to identify via Magnetic Resonance Imaging (MRI) glabellar muscle parameters that display an influence on the distribution of individual glabellar contraction patterns. Thirty-four healthy young individuals of Caucasian Polish descent were investigated (17 women, 17 men) with a mean age of 23.6 years and a mean BMI of 22.8 kg/m2. MRI-based measurements of length, thickness, width and surface area of procerus, corrugator supercilii, orbicularis oculi and frontalis muscles were conducted. Unadjusted models revealed that there was no statistically significant difference between the five glabellar contraction types and the investigated muscle parameters indicating that independent of the skin rhytid pattern, the underlying musculature was not different between the investigated groups in this sample with all p ≥ 0.102. Adjusted models revealed that sex was the most influential factor due to males displayed in general higher values for the investigated parameters when compared to females. The results of this study reveal that based on the MRI parameters investigated and based on the investigated cohort, there does not appear to be a strong relationship between glabellar contraction patterns and underlying glabella muscle anatomy. Utilizing glabellar contraction patterns to design neuromodulator treatment algorithms may be of variable clinical merit.

Adjuncts to annuloplasty in atrial functional mitral regurgitation.

Atrial fibrillation is the most common cardiac arrhythmia, leading to progressive dilation of cardiac chambers, abnormal contraction patterns of the atria and ventricles and, potentially, atrioventricular valvular insufficiency. Moreover, heart failure with preserved ejection fraction is often present and closely intertwined with disease initiation and progression. Surgical valve repair with a true-sized ring annuloplasty is a well-established treatment option in atrial functional mitral regurgitation. While early results are good, recent studies have brought the durability of this repair approach into question, highlighting the need for further refinement of the surgical strategy. In particular, repair strategies that simultaneously target the mitral valve as well as the left ventricle could provide improved repair durability.

Muscle thickness of lateral abdominal muscles in sitting and standing positions during abdominal drawing-in maneuver and abdominal bracing among healthy adults

Background: Spinal stabilization exercises, such as abdominal drawing maneuvers (ADIM) and abdominal bracing (AB), are crucial in alleviating low back pain, especially in functional positions such as sitting and standing. However, few studies have investigated the contraction patterns of the lateral abdominal muscles during ADIM and AB in these daily living positions (i.e., sitting and standing). Objective: The study aimed to investigate the thickness of transverse abdominis (TrA), internal abdominal oblique (IO), and external abdominal oblique (EO) during ADIM and AB between sitting and standing positions. Materials and methods: Twenty-four healthy adults (12 males, 12 females) without low back pain or other orthopedic conditions were assessed in sitting and standing positions while performing ADIM and AB. Real-time ultrasound imaging was used to measure the thickness of the TrA, IO, and EO during the ADIM and AB. Results: Muscle thickness of TrA and IO was significantly greater during ADIM when compared to AB (p<0.05). TrA thickness during AB was significantly greater in sitting than standing (p<0.05), but ADIM showed no difference in both positions. ADIM and AB can produce contraction of the lateral abdominal muscles (LAM) in both sitting and standing positions. Conclusion: ADIM and AB can produce contraction of the LAM in both sitting and standing positions. However, ADIM can activate TrA and IO muscles better than AB. Therefore, clinicians may initially consider using ADIM to teach individuals who need core stability exercises such as low back pain.

EN FACE OPTICAL COHERENCE TOMOGRAPHY MORPHOLOGY OF MACULAR PUCKER CORRELATES WITH METAMORPHOPSIA: Possible Role of the Henle Fiber Layer.

To describe macular pucker contraction patterns with en face optical coherence tomography (OCT), to provide a correlation with metamorphopsia scores, and to discuss the protective role of the Henle fiber layer (HFL) against tangential traction. Retrospective, institutional, observational, and consecutive case series. Clinical charts, M-charts scores, and structural and en face OCT imaging of patients diagnosed with macular pucker were reviewed. A 120 eyes of 114 consecutive patients diagnosed with macular pucker were included. En face OCT patterns of macular pucker contraction were foveal in 51 of 120 eyes (42.5%) and extrafoveal in 69 of 120 eyes (57.5%). Foveal macular puckers had regular, a concentric, circle morphology in the HFL (46/51 eyes, 90.2%), whereas extrafoveal membranes had irregular, distorted, circular HFL morphology (62/69 eyes, 89.8%; P < 0.001). Foveal contraction morphology and regular HFL pattern, as well as extrafoveal contraction morphology and an irregular HFL pattern, highly correlated one with another (P < 0.001 in both cases). Foveal macular puckers with regular HFL patterns had significantly less vertical and horizontal M-charts scores as compared with extrafoveal membranes with irregular HFL (P < 0.001 in both cases). Ellipsoid zone and external limiting membrane defects were rare in the parafoveal region (5/120 eyes, 4.2%). Visual acuity did not correlate with metamorphopsia scores (P = 0.903). En face OCT imaging identifies macular pucker contraction patterns that correlate with metamorphopsia scores and that can be used alongside the current structural OCT staging system to guide clinicians in the surgical decision-making process.

Mechanical boundary conditions for motor protein dictate geometric pattern and dynamics of actin gel contraction

Mechanical boundary conditions for motor protein dictate geometric pattern and dynamics of actin gel contraction

The effect of Rebozo technique on perceived labour pain and childbirth experience: A randomized controlled trial.

Pain, stress, and anxiety experienced during childbirth can have detrimental effects on labor and delivery. The rebozo technique is an ancestral method used to minimize pain and enhance relief during gestation. This study aimed to investigate the effects of the rebozo technique on the birth process and its probable benefits on the birth experience. This survey was conducted from January to May 2021 in a randomized and controlled manner. A total of 113 pregnant women with their first children were surveyed. Women between 37 and 41 weeks of gestation without complications who were admitted to the delivery room with a cervical dilation of 4 cm or more were chosen as participants. In the Rebozo group, subjects were randomly selected by trained personnel to apply the standardized method, while the control group received a relaxing massage. Cervical dilation, fetal position, contraction patterns, and measures related to the birth experience were key indicators. Women in the rebozo group had lower pain levels during birth and greater birth satisfaction. Mean cervical dilation in the latent phase was 5.61 cm in the rebozo group and 5.71 cm in the control group. In the active phase, cervical dilatation was 6.03 cm in the rebozo group and 6.68 cm in the control group, and this difference was statistically significant (P < .001). In the transition phase, the birth time was 46.29 minutes in the rebozo group and 68.71 minutes in the control group (P = <.007**). In the total birth experience score, the rebozo group received an average of 68.52 points, while the control group received 51.58 points (P < .001). This research has established that the use of the rebozo technique throughout labor helps enhance her feelings about being pregnant, as well as heightening fulfillment with delivery.

Spontaneous enteric nervous system activity generates contractile patterns prior to maturation of gastrointestinal motility.

Spontaneous neuronal network activity is essential to the functional maturation of central and peripheral circuits, yet whether this is a feature of enteric nervous system development has yet to be established. Although enteric neurons are known exhibit electrophysiological properties early in embryonic development, no connection has been drawn between this neuronal activity and the development of gastrointestinal (GI) motility patterns. We use exvivo GI motility assays with newly developed unbiased computational analyses to identify GI motility patterns across mouse embryonic development. We find a previously unknown pattern of neurogenic contractions termed "clustered ripples" that arises spontaneously at embryonic day 16.5, an age earlier than any identified mature GI motility patterns. We further show that these contractions are driven by nicotinic cholinergic signaling. Clustered ripples are neurogenic contractile activity that arise from spontaneous ENS activity and precede all known forms of neurogenic GI motility. This earliest motility pattern requires nicotinic cholinergic signaling, which may inform pharmacology for enhancing GI motility in preterm infants.

Abstract Or107: MyBP-HL nonsense mutations fail in sarcomere incorporation leads to modifications in myocyte contraction trough calcium modifications.

Introduction: Heart function depends on the cardiomyocyte contractile apparatus and proper sarcomere protein expression. Mutations in sarcomere genes cause inherited forms of cardiomyopathy and arrhythmias, including atrial fibrillation. AF is the most common cardiac arrhythmia and is associated with ischemic stroke, heart failure, and substantial morbidity and mortality. Recently, our group described a novel sarcomere component, myosin binding protein-H like (MyBP-HL), that is mainly expressed in the cardiac atria. MyBP-HL is composed of two immunoglobulin domains and one fibronectin domain, with homology to last three C-terminal domains of cardiac myosin binding protein-C (cMyBP-C). cMyBP-C nonsense mutations prevent his incorporation into the sarcomere. C-MyBP-C truncated peptides are identified by cells as poisoning peptides, and they are rapidly degraded. cMyBP-C nonsense mutations are causative of hypertrophic cardiomyopathy (HCM). The MyBP-HL Arg255stop variant has been described in humans and has been linked to ventricular conduction system abnormalities, atrial enlargement, dilated cardiomyopathy, and atrial and ventricular arrhythmias. The gnomAD database reports 9 nonsense mutations for MYBPHL in humans (Gln29, Trp54, Arg113, Tyr123, Trp158, Trp192, Lys250, Arg255, and Tyr307). Hypothesis: MYBPHL nonsense mutations fail to incorporate into the sarcomere will lead to contractile disfunction. Results: We demonstrated that MyBP-HL overexpression showed to be able to incorporate in a similar pattern to cMyBP-C C-zone doublets. Nevertheless, nonsense mutations disrupt normal sarcomere localization. MyBP-HL nonsense mutations promote an increase in contraction amplitude and slower relaxation kinetics. Also, we observed an increase in sarcomere length. Similarly, MyBP-HL nonsense mutations lead to increase in amplitude peak of calcium transients, and reduction in velocity to maximal calcium peak. In accordance with calcium modifications, we observed through mass spectrometry an increase in calpain 6 abundance promoted by MyBP-HL nonsense mutations. Conclusion: Based on these data, we demonstrated that MYBPHL nonsense mutations prevent MyBP-HL incorporation into the thick filament. The failure of MyBP-HL truncating peptides to incorporate into the sarcomere leads to a deficiencies in myocytes contraction patterns, changes in calcium patterns and increase in degradation proteins abundance, which are related to AF prevalence.

The effects of mitral stenosis on right ventricular mechanics assessed by three-dimensional echocardiography

Mitral stenosis (MS) is a complex valvular pathology with significant clinical burden even today. Its effect on the right heart is often overlooked, despite it playing a considerable part in the symptomatic status. We enrolled 39 mitral valve stenosis patients and 39 age- and gender-matched healthy controls. They underwent conventional, speckle-tracking and 3D echocardiographic examinations. The 3D data was analyzed using the ReVISION software to calculate RV functional parameters. In the MS group, 3D RV ejection fraction (EF) (49 ± 7% vs. 61 ± 4%; p < 0.001), global circumferential (GCS) (− 21.08 ± 5.64% vs. − 25.07 ± 4.72%; p = 0.001) and longitudinal strain (GLS) (− 16.60% ± 4.07% vs. − 23.32 ± 2.82%; p < 0.001) were reduced. When comparing RV contraction patterns between controls, MS patients in sinus rhythm and those with atrial fibrillation, radial (REF) (32.06 ± 5.33% vs. 23.62 ± 7.95% vs. 20.89 ± 6.92%; p < 0.001) and longitudinal ejection fraction (LEF) (24.85 ± 4.06%; 17.82 ± 6.16% vs. 15.91 ± 4.09%; p < 0.001) were decreased in both MS groups compared to controls; however, they were comparable between the two MS subgroups. Anteroposterior ejection fraction (AEF) (29.16 ± 4.60% vs. 30.87 ± 7.71% vs. 21.48 ± 6.15%; p < 0.001) showed no difference between controls and MS patients in sinus rhythm, while it was lower in the MS group with atrial fibrillation. Therefore, utilizing 3D echocardiography, we found distinct morphological and functional alterations of the RV in MS patients.

Neuromodulators in Men.

Botulinum toxin treatment is gaining popularity among men for cosmetic purposes driven by workplace competition and a desire for confidence and youthfulness. Because of the unique features of male facial anatomy, careful consideration is necessary during assessment and treatment execution. The peer-reviewed literature on male facial anatomy in relation to neuromodulator treatment was analyzed with a particular emphasis on studies involving male subjects and the use of botulinum toxin type A. Anatomic differences in muscle mass and contraction patterns between men and women help guide treatment. Men appear to require higher doses for effective treatment of facial wrinkles and, in the case of glabellar lines, often require double the standard dose for women. Treatment of the frontalis muscle in men, responsible for forehead creases, requires precise dosage and placement to avoid brow ptosis. The lateral canthal wrinkles are often the first area that men seek consultation for. Although FDA approval for lower face regions is lacking, off-label use can still be considered. Successful botulinum toxin treatment in men necessitates understanding facial anatomy, customized treatment plans, and appropriate dosing. Further research is warranted to refine protocols and enhance outcomes for male patients.

Assessment of the Efficacy and Durability of IncobotulinumtoxinA in the Treatment of the Upper Face in Adult Women.

IncobotulinumtoxinA (Xeomin®) is used in the treatment of dynamic wrinkles and the aesthetic repositioning of facial structures. The duration of its muscular effect typically extends for around 4months. However, the residual aesthetic benefit can be observed for a longer period. To date, the long-term aesthetic benefit of incobotulinumtoxinA in facial aesthetics has not been systematically evaluated. This study aimed to evaluate longitudinally the duration and aesthetic benefits of incobotulinumtoxinA in the treatment of the upper face in adult women. A quasi-experimental, evaluator-blind, clinical trial involving 28 adult women (30-60years old) with facial movement lines, undergoing treatment of the upper face with incobotulinumtoxinA by two injectors, following an individualized protocol (ONE21 and glabellar contraction patterns) was performed. Participants were evaluated on the day of the intervention (day0) and days30, 120, 180, and 240, and subjected to standardized photographs. The following outcomes were evaluated blindly at each visit: Merz Aesthetics Facial Contraction Scale (MAS), GAIS (Global Aesthetic Improvement Scale), and patient satisfaction. Adverse effects were evaluated at each visit. Participants ranged in age from 30 to 60years, 93% were self-declared white, and most of their baseline MAS scores for dynamic lines were moderate and severe. All the parameters presented significative reduction from baseline until day180. At day240, the dynamic MAS scores were lower than baseline for forehead lines in 15.4% (95% confidence interval (CI) 0.8-30.0%) of the participants, for glabellar lines in 38.5% (95%CI 18.8-58.1%), and for crow's feet lines in 26.9% (95%CI 9.0-44.8%). Aesthetic improvement compared to baseline was identified in 35% (CI 95% 23‒50%) of the participants at day240, and 62% (CI 95% 42‒81%) of the sample kept reporting some satisfaction with the procedure. The aesthetic treatment of the upper face with incobotulinumtoxinA demonstrates enduring clinical benefits, and patient satisfaction lasting up to 180days in most participants. The length of efficacy, which exceeded those reported in the literature, may be attributed to the use of techniques based on individualized assessment such as ONE21 and glabellar patterns of contraction.

Trendelenburg gait after total hip arthroplasty due to reduced muscle contraction of the hip abductors and extensors

BackgroundDespite experiencing pain relief and improved activities of daily living after total hip arthroplasty (THA) for osteoarthritis of the hip, a Trendelenburg gait may be observed in some patients. The concentric and eccentric contraction patterns of hip muscles in a Trendelenburg gait are not well understood. MethodsThis study included 89 patients (28 males and 61 females, mean age 66.5 ± 8.4 years, mean postoperative period 1.3 ± 0.4 years) after unilateral THA without functional impairment on the contralateral side. Gait analysis utilized a three-dimensional motion capture system to assess pelvis and hip angles, hip moment, and hip power. A Trendelenburg gait was defined as positive when nonoperative pelvic descent occurred at 30 % of the gait cycle, equivalent to mid-stance. Patients were classified into Trendelenburg gait-positive and -negative groups for statistical analysis. Unpaired t-test and chi-square test were used to compare the two groups. Multiple regression analysis was conducted to identify factors associated with the presence of a Trendelenburg gait. ResultsA Trendelenburg gait was observed in 24 patients (27 %). Multiple regression analysis indicated that abduction (p < 0.01) and extension (p = 0.03) of hip joint power were significant determining of a Trendelenburg gait. Patients with a Trendelenburg gait exhibited reduced eccentric contraction of the hip abductor muscles and decreased concentric contraction of hip extensor muscles during early to mid-stance of their gait. ConclusionCentrifugal contraction of hip abductor muscles and diminished eccentric contractility of hip extensor muscles appear crucial for hip stabilization mechanisms during gait after THA.

Differential amplification and contraction of satellite DNAs in the distinct lineages of the beetle Euchroma gigantea

Satellite DNA (satDNA) consists of tandem repeat sequences that typically evolve rapidly through evolutionary mechanisms, including unequal crossover, transposition events, and others. The evolutionary history of Euchroma gigantea is marked by complex chromosomal evolution between lineages, making this species an interesting model for understanding satDNA evolution at intraspecies level. Therefore, our aim was to comprehend the potential contribution of satDNAs to the greater chromosomal differentiation of evolutionary lineages in E. gigantea by investigating the differential patterns of amplification and contraction of the repeats. To achieve this, we employed de novo identification of satDNA using RepeatExplorer and TAREAN, allowing the satellitome characterization between lineages. A total of 26 satDNA families were identified, ranging from 18 to 1101 nucleotides in length, with most families being shared between individuals/lineages, as predicted by the library hypothesis, except for the satDNA EgiSat21-168 that was absent for Northeast Lineage. The total satDNA content of the individuals was less than 11.2%, and it appeared to increase in two directions following the chromosomal evolution model. Thirteen satDNAs exhibited different patterns of amplification, and nine ones were contracted among individuals. Additionally, most repeats showed a divergence of about 10% for these satDNAs, indicating satellitome differentiation for each lineage/individual. This scenario suggests that the expansion of the satellitome occurred differentially among individuals/lineages of E. gigantea, with the contribution of various DNA turnover mechanisms after geographical isolation, and that they could be involved with karyotype evolution.

Enhancing Chicago Classification diagnoses with functional lumen imaging probe-mechanics (FLIP-MECH).

Esophageal motility disorders can be diagnosed by either high-resolution manometry (HRM) or the functional lumen imaging probe (FLIP) but there is no systematic approach to synergize the measurements of these modalities or to improve the diagnostic metrics that have been developed to analyze them. This work aimed to devise a formal approach to bridge the gap between diagnoses inferred from HRM and FLIP measurements using deep learning and mechanics. The "mechanical health" of the esophagus was analyzed in 740 subjects including a spectrum of motility disorder patients and normal subjects. The mechanical health was quantified through a set of parameters including wall stiffness, active relaxation, and contraction pattern. These parameters were used by a variational autoencoder to generate a parameter space called virtual disease landscape (VDL). Finally, probabilities were assigned to each point (subject) on the VDL through linear discriminant analysis (LDA), which in turn was used to compare with FLIP and HRM diagnoses. Subjects clustered into different regions of the VDL with their location relative to each other (and normal) defined by the type and severity of dysfunction. The two major categories that separated best on the VDL were subjects with normal esophagogastric junction (EGJ) opening and those with EGJ obstruction. Both HRM and FLIP diagnoses correlated well within these two groups. Mechanics-based parameters effectively estimated esophageal health using FLIP measurements to position subjects in a 3-D VDL that segregated subjects in good alignment with motility diagnoses gleaned from HRM and FLIP studies.

Pleistocene climate oscillations have shaped the expansion and contraction speciation model of the globose Eriosyce sect. Neoporteria cacti in Central Chile.

Pleistocene climatic oscillations, characterized by arid (interglacial) and pluvial (glacial) phases, have profoundly impacted the floras of Mediterranean climates. Our study investigates the hypothesis that these climatic extremes have promoted phases of range expansion and contraction in the Eriosyce sect. Neoporteria, resulting in pronounced genetic structuring and restricted gene flow. Utilizing nuclear microsatellite markers, we genotyped 251 individuals across 18 populations, encompassing all 14 species and one subspecies within the Eriosyce sect. Neoporteria. Additionally, Species Distribution Models (SDMs) were employed to reconstruct past (Last Interglacial, Last Glacial Maximum, Mid-Holocene) and current potential distribution patterns, aiming to delineate the climatic influences on species' range dynamics. The gene flow analysis disclosed disparate levels of genetic interchange among species, with marked restrictions observed between entities that are geographically or ecologically separated. Notably, E. subgibbosa from Hualpen emerged as genetically distinct, warranting its exclusion for clearer genetic clustering into north, central, and south clusters. The SDMs corroborated these findings, showing marked range expansions during warmer periods and contractions during colder times, indicating significant shifts in distribution patterns in response to climatic changes. Our findings emphasize the critical role of Pleistocene climatic fluctuations in driving the dynamic patterns of range expansions and contractions that have led to geographic isolation and speciation within the Eriosyce sect. Neoporteria. Even in the face of ongoing gene flow, these climate-driven processes have played a pivotal role in sculpting the species' genetic architecture and diversity. This study elucidates the complex interplay between climatic variability and evolutionary dynamics among Mediterranean cacti in central Chile, highlighting the necessity of considering historical climatic millenial oscillations in conservation and evolutionary biology studies.

Geodetic constraints on three-component motion of the Ordos block (China) and their implications for lithospheric dynamics

Abstract The Ordos block is a rigid portion of the North China Craton lying within the India-Eurasia collision zone that experiences little internal deformation, but is surrounded by active faulting, extensional grabens, and seismicity. In the surrounding region, geodetic studies have imaged complex crustal deformation, while seismic studies have suggested that the lithosphere is encountering regional modification by mantle convection. The Ordos block thus presents a valuable opportunity to compare seismic and geodetic constraints and investigate geodynamic processes affecting the region’s lithosphere. We here robustly image vertical land motion and horizontal strain rates using observations from the geographically extensive Global Navigation Satellite System and leveling networks in and around the Ordos block. Our results indicate that the Ordos block uplifts with some lateral variability at 0.5–2.0 mm/yr. In the northeastern Ordos block and Datong volcanic area, the crustal uplift rates are 2.0–4.0 mm/yr on average, much faster than those elsewhere on the block. We correct for non-tectonic vertical motion from surface hydrological loading and glacial isostatic adjustment, finding that these do not explain the vertical rate anomalies. Horizontal crustal extension and uplift are accompanied by a pattern of crustal contraction at the Datong volcanic field. Additionally, we find uplift west of and subsidence east of the Qinling Orogenic Belt, which are inconsistent with eastward crustal extrusion along it, suggesting instead a negligible migration of crustal materials especially to the east of 106°E. Comparing the geodetic measurements to evidence from seismic velocity anomalies and numerical simulation, we argue that the motions are consistent with lithospheric re-equilibration resulting from the heterogeneous thinning of the lithosphere by convective mantle upwelling and radial flow as well as shortening from the India-Eurasia collision.

Exercise-induced regional heterogeneity of myocardial left ventricular contraction in hereditary long QT syndrome

Abstract Background Hereditary long QT syndrome (LQTS) is characterized by prolonged ventricular repolarization and an increased risk for ventricular arrhythmias (VA) and sudden cardiac death. Dispersion of ventricular repolarization in LQTS may be more pronounced during exercise and not only impacts the heart’s electrical functions but also the pattern of mechanical contraction. Little is known about the intraventricular heterogeneity of wall motion abnormalities in LQTS patients. Methods In this cross-sectional study we quantify regional, transmural, and longitudinal alterations in left ventricular (LV) contraction at rest, during exercise, and recovery in genetically confirmed LQTS patients and healthy controls to evaluate their value in differentiating high risk patients as defined by a history of VA. ECG and echocardiographic assessments were conducted during rest, peak ergometer activity (105 to 125 bpm), and four minutes into recovery phases. Longitudinal strain (LStr) parameters were measured for each LV segment separately. We differentiated LStr variations as heterogeneity of LStr amplitude (hetLStr; standard deviation [SD] or mean range) and dispersion of time-to-peak LStr (disLStr; SD or mean range). Here, we present the analyses of disLStr. Results At present, 15 patients with genetically confirmed LQTS (LQT1: 8, LQTS 2: 7; mean QTc 475 ± 46 ms) have been included of which 9 had a history of VA. In addition, we collected data from 8 age- and gender-matched control patients (mean QTc 401 ± 18 ms). LV ejection fraction and LStr were not significantly different between the LQTS and control groups. However, LQTS patients exhibited a significantly lower mean LStr in both the endocardial and epicardial layers across all phases compared to control. We observed a significantly more pronounced disLStr across all segments in the LQTS group during the rest and recovery phases in the endocardial layer and during all phases in the epicardial layer. Regional differences (apical vs. basal) were found in all LQTS patients only endocardially at rest. Globally, disLStr showed transmural differences (epicardial vs. endocardial) in both asymptomatic and symptomatic LQTS patients during peak exercise and recovery. Upon segmental analysis, it was observed that symptomatic patients exhibited these transmural differences apically already at rest (p=.004), as well as in the basal region during peak exercise (p=.01), and in the apical region during recovery (p=.02). Conclusion LQTS patients show regional (base to apex) and transmural (endocardial to epicardial) heterogeneities in myocardial contraction at rest, during exercise, and recovery as compared to healthy patients. These regional variations in myocardial contraction patterns may be more pronounced in high risk LQTS patients. Ongoing analyses of hetLStr are in progress to corroborate our findings.