Spine Length Research Articles

Discovery of a new Kinorhyncha species from the uncharted South Orkney Trench (Southern Ocean)

The knowledge about the deep-sea Kinorhyncha community has increased considerably in recent years. However, the records of kinorhynchs inhabiting hadal depths are still extremely limited. In the present study, we describe a new species of Echinoderes discovered from the South Orkney Trench, Southern Ocean. Echinoderes australis sp. nov. is characterized by the presence of middorsal acicular spines on segments 4-8 and lateroventral ones on segments 6-9, and tubes in lateroventral position on segment 5, in lateral accessory position on segment 8, and in laterodorsal position on segment 10. Additionally, the new species has conspicuous papillary flaps on segments 8-9. Among its morphological characteristics, the increase in length of the middorsal spine of segment 8 and lateroventral spines of segment 9 in relation to those of the previous segments are striking features, showing a whip-like appearance. E. australis sp. nov. Becomes the third hadal species of the phylum. In addition, we provide morphological information on the two other species found in the trench. Finally, we study in detail the diversity and distribution patterns of the Kinorhyncha of the South Orkney Trench, addressing aspects such as species richness, abundance, number of adults versus juveniles and the effect of bathymetry on the community composition.

Taxonomic re-evaluation of the Brachionus calyciflorus species complex (Rotifera) in Japanese freshwaters

AbstractRecently, the Brachionus calyciflorus species complex was divided into four nominal species: B. calyciflorus sensu stricto (s.s.) Pallas, 1766; Brachionus dorcas Gosse, 1851, Brachionus elevatus Michaloudi et al., 2018, and Brachionus fernandoi Michaloudi et al., 2018 based on the results of both morphological and molecular investigations. We applied this systematic approach to B. “calyciflorus” collected from lakes and ponds in various parts of Japan to examine spatial and temporal distributions of these species. We found that all four species indeed distributed in Japan. Among the species, B. fernandoi exhibited a somewhat different occurrence pattern and morphology. Generally, B. fernandoi appeared to occur in the winter–spring, while the other three species seemed to occur in the early summer–late autumn. A seasonal succession from B. fernandoi-dominant community to other species-dominant communities was observed in the same lakes/ponds. A statistical analysis showed that B. fernandoi-dominant species composition was also related to low temperatures. It was also found that the body of B. fernandoi was more elongated compared to those of other species. These results suggest that B. fernandoi is a distinct species in terms of morphology and phenology. Among the other three species, we observed a variation in the length of posterolateral spines. However, it was not clear if this variation is a trait that distinguish these species morphologically. In addition, some of these species co-occurred in the same lakes and ponds. The mechanism by which they coexist is a topic for future study.

WuYou decoction effectively reduces neuronal damage, synaptic dysfunction, and Aβ production in rats exposed to chronic sleep deprivation by modulating the Aβ-related enzymes and SIRT1/Nrf2/NF-κB pathway

Ethnopharmacological relevanceChronic sleep deprivation (CSD) can result in neuronal damage, synaptic dysfunction, Aβ production, neuroinflammation, and ultimately cognitive deterioration. WuYou Decoction (WYD), a contemporary prescription, has shown promise in enhancing sleep quality and cognitive performance in individuals with insomnia. However, the specific molecular mechanisms responsible for the neuroprotective effects of WYD on CSD remain incompletely understood. Aim of the studyThis study aimed to investigate the neuroprotective effects of WYD on the CSD model and its molecular mechanism. Materials and methodsUHPLC-MS/MS analysis was utilized to analyze the active ingredients of WYD extract. The study employed the multi-platform water environment method to establish the CSD model in rats. Subsequent to treatment with varying doses of WYD in CSD rats, cognitive function and pathological alterations in hippocampus and cortex, including neuronal damage, synaptic dysfunction, Aβ production, and neuroinflammation, were evaluated through a combination of Morris Water Maze test, HE staining, Nissl staining, Golgi-Cox staining, Transmission electron microscope, ELISA, Immunohistochemistry staining, Immunofluorescence staining and Western blot. ResultsUHPLC-MS/MS analysis revealed a total of 99 active ingredients were identified from the WYD extract. The administration of WYD exhibited a mitigation of cognitive decline in the model of CSD, as evidenced by increased neuron count in the hippocampus and cortex, and improved density and length of dendritic spines in these brain regions. Furthermore, WYD was found to suppress the Aβ production, and inhibit the expression of BACE1, PS1, GFAP, IBA1, IL-1β, IL-6, TNF-α, phosphorylated IκBα (Ser32) and phosphorylated NF-κB p65 (Ser536) in the hippocampus and cortex, while also increasing the levels of PSD95, SYN1, ADAM10, IDE, SIRT1 and Nrf2. ConclusionsWYD exhibits neuroprotective properties in CSD, potentially through modulation of the Aβ-related enzymes and SIRT1/Nrf2/NF-κB pathway.

Chronic Lithium Treatment Alters NMDA and AMPA Receptor Synaptic Availability and Dendritic Spine Organization in the Rat Hippocampus.

The mechanisms underlying the action of lithium (LiCl) in bipolar disorder (BD) are still far from being completely understood. Previous evidence has revealed that BD is characterized by glutamate hyperexcitability, suggesting that LiCl may act, at least partially, by toning down glutamatergic signaling abnormalities. In this study, taking advantage of western blot and confocal microscopy, we used a combination of integrative molecular and morphological approaches in rats exposed to repeated administration of LiCl at a therapeutic dose (between 0.6 and 1.2 mmol/l) and sacrificed at two different time points, i.e., 24 hours and 7 days after the last exposure. We report that repeated LiCl treatment activates multiple, parallel, but also converging forms of compensatory neuroplasticity related to glutamatergic signaling. More specifically, LiCl promoted a wave of neuroplasticity in the hippocampus, involving the synaptic recruitment of GluN2A-containing NMDA receptors, GluA1-containing AMPA receptors, and the neurotrophin BDNF that are indicative of a more plastic spine. The latter is evidenced by morphological analyses showing changes in dendritic spine morphology, such as increased length and head diameter of such spines. These changes may counteract the potentially negative extra-synaptic movements of GluN2B-containing NMDA receptors as well as the increase in the formation of GluA2-lacking Ca2+-permeable AMPA receptors. Our findings highlight a previously unknown cohesive picture of the glutamatergic implications of LiCl action that persist long after the end of its administration, revealing for the first time a profound and persistent reorganization of the glutamatergic postsynaptic density receptor composition and structure.

Characteristics of Morphological Changes in Fins according to Larval Growth of Red Spotted Grouper, Epinephelus akaara.

This study investigated the fin development and morphological characteristics according to larval growth in order to obtain information on behavioral characteristics and optimal stocking density during red seed grouper seed production. To examine the growth and fin development process of the larvae, we randomly sampled at 1, 3, 5, 7, 9, 10, 11, 13, 15, 17, 19, 20, 25, 30, 39, 45, 51, and 72 days after hatching. External morphology was observed and measured using an optical microscope. To observe skeletal development, larvae at 13, 20, 30, and 72 days after hatching were fixed in formalin and stained for cartilage and bone examination. At 9-10 DAH, red spotted grouper larvae (2.74±0.1 to 3.0±0.2 mm TL) exhibited a second dorsal fin spine and pelvic fin spine, which subsequently elongated. At 19-20 DAH, the larvae (5.7±0.1 to 6.1±0.1 mm TL) have the lengths of the second dorsal fin spine and pelvic fin spine average 34% and 31% to total length, respectively. From 30 to 72 DAH (12.6±0.4 to 56.0±0.2 mm TL), the length of the second dorsal fin spine and pelvic fin spine to total length decreased from 27% to 8% for the dorsal fin and 21% to 14% for the pelvic fin, respectively. At 30 DAH (12.6±0.4 mm TL), the larvae reached the complete count of fin rays in each fin. At 39 DAH (20.28±3.07 mm TL), the larvae had fin shapes similar to those of adults. At 13-30 DAH (4.2±0.1 to 12.6±0.9 mm TL), barbs and spinules were distributed along the ridges of the second dorsal and pelvic fin spines. However, at 72 DAH, these barbs and spinules were no longer observed on the fins. During the seed production process, red spotted grouper larvae tend to cluster in the morning, and during this time, entanglement of barbs and spinules on the second dorsal and pelvic fin spines can lead to mortality. Therefore, it is considered essential to focus on managing the behavioral patterns and appropriate rearing density of red spotted grouper larvae from the emergence of barbs and spinules on the second dorsal and pelvic fin spines until they regress and metamorphosis is completed.

522: Spine length reduction during the course of day in pediatric radiotherapy patients

522: Spine length reduction during the course of day in pediatric radiotherapy patients

Reducing Filamin A Restores Cortical Synaptic Connectivity and Early Social Communication Following Cellular Mosaicism in Autism Spectrum Disorder Pathways.

Communication in the form of nonverbal, social vocalization, or crying is evolutionary conserved in mammals and is impaired early in human infants that are later diagnosed with autism spectrum disorder (ASD). Defects in infant vocalization have been proposed as an early sign of ASD that may exacerbate ASD development. However, the neural mechanisms associated with early communicative deficits in ASD are not known. Here, we expressed a constitutively active mutant of Rheb (RhebS16H), which is known to upregulate two ASD core pathways, mTOR complex 1 (mTORC1) and ERK1/2, in Layer (L) 2/3 pyramidal neurons of the neocortex of mice of either sex. We found that cellular mosaic expression of RhebS16H in L2/3 pyramidal neurons altered the production of isolation calls from neonatal mice. This was accompanied by an expected misplacement of neurons and dendrite overgrowth, along with an unexpected increase in spine density and length, which was associated with increased excitatory synaptic activity. This contrasted with the known decrease in spine density in RhebS16H neurons of 1-month-old mice. Reducing the levels of the actin cross-linking and adaptor protein filamin A (FLNA), known to be increased downstream of ERK1/2, attenuated dendrite overgrowth and fully restored spine properties, synaptic connectivity, and the production of pup isolation calls. These findings suggest that upper-layer cortical pyramidal neurons contribute to communicative deficits in a condition known to affect two core ASD pathways and that these mechanisms are regulated by FLNA.

Morphometric study of the exuviae of Aeshna juncea (Linnaeus, 1758) (Odonata: Aeshnidae)

This study assessed various anatomical parameters of exuviae of three distinct populations of Aeshna juncea (Linnaeus, 1758) collected in Iran, the Netherlands and France. Fifty specimens (25 males, 25 females) from each country were analysed in detail. We measured 20 morphological traits for females and 19 traits for males. We found out that body length, left foreleg, left forewing sheath, left hindwing sheath, length of cercus, epiproct, epiproct spine, paraprocts and length of abdominal spines were larger in specimens originating from Iran compared to specimens collected in the studied areas of France and the Netherlands. In contrast, width of head and minimal width of prementum were larger in specimens from the Netherlands. According to our results, the measured morphological parameters indicated a greater similarity between the specimens found in France and the Netherlands compared to the specimens recorded in Iran. The presented data might be useful for future comparison of other populations of A. juncea throughout Eurasia.

Genetic mechanisms of axial patterning in Apeltes quadracus

Abstract The genetic mechanisms underlying striking axial patterning changes in wild species are still largely unknown. Previous studies have shown that Apeltes quadracus fish, commonly known as fourspine sticklebacks, have evolved multiple different axial patterns in wild populations. Here, we revisit classic locations in Nova Scotia, Canada, where both high-spined and low-spined morphs are particularly common. Using genetic crosses and quantitative trait locus (QTL) mapping, we examine the genetic architecture of wild differences in several axial patterning traits, including the number and length of prominent dorsal spines, the number of underlying median support bones (pterygiophores), and the number and ratio of abdominal and caudal vertebrae along the anterior–posterior body axis. Our studies identify a highly significant QTL on chromosome 6 that controls a substantial fraction of phenotypic variation in multiple dorsal spine and pterygiophore traits (~15%–30% variance explained). An additional smaller-effect QTL on chromosome 14 contributes to the lengths of both the last dorsal spine and anal spine (~9% variance explained). 1 or no QTL were detected for differences in the numbers of abdominal and caudal vertebrae. The major-effect patterning QTL on chromosome 6 is centered on the HOXDB gene cluster, where sequence changes in a noncoding axial regulatory enhancer have previously been associated with prominent dorsal spine differences in Apeltes. The QTL that have the largest effects on dorsal spine number and length traits map to different chromosomes in Apeltes and Gasterosteus, 2 distantly related stickleback genera. However, in both genera, the major-effect QTL for prominent skeletal changes in wild populations maps to linked clusters of powerful developmental control genes. This study, therefore, bolsters the body of evidence that regulatory changes in developmental gene clusters provide a common genetic mechanism for evolving major morphological changes in natural species.

Vertebral Column Height Andpredisposition To Low Back Pain- Observational Study

Background and purpose: Research was done to find out the relationship between lumbar lordosis and radiologic variables, lumbar lordosis and clinical variables, which showed that lordosis itself, do not have any predisposition to low back pain. Weak abdominal muscles are also associated with low back pain. As no previous study was done to correlate vertebral column height and low back pain, this study is intended to analyze whether these variables are predisposed to low back pain. Case description (Subjects): 200 subjects were approached through systematic convenient sampling which included 100 people (50 males and 50 females) with back pain and 100 people (50 male and 50 female without back pain). Intervention and methods: Subjects for the study were assessed according to the following parameters; vertebral column height, abdominal girth measurement, bilateral SLR, hip waist ratio, VAS scale. Results: Pain scores correlated significantly to the length of spinal segment mainly cervical spine (p=0.05) and lumbar spine (p=0.01) and also to bilateral SLR hold time (p=0.01). The bilateral SLR correlates significantly to a Total spine length and length of thoracic spine (p=0.01) while there was no correlation between bilateral hold time and length of cervical spine. Conclusion: This study has found that the length of the spinal column should be given due importance when assessing the risk of developing low back pain.

Impaired Experience-Dependent Theta Oscillation Synchronization and Inter-Areal Synaptic Connectivity in the Visual Cortex of Fmr1 KO Mice.

Fragile X syndrome (FX) is the most prevalent inheritable form of autism spectrum disorder (ASD), characterized by hypersensitivity, difficulty in habituating to new sensory stimuli, and intellectual disability. Individuals with FX often experience visual perception and learning deficits. Visual experience leads to the emergence of the familiarity-evoked theta band oscillations in the primary visual cortex (V1) and the lateromedial area (LM) of mice. These theta oscillations in V1 and LM are synchronized with each other, providing a mechanism of sensory multi-areal binding. However, how this multi-areal binding and the corresponding theta oscillations are altered in FX is not known. Using iDISCO whole brain clearing with light-sheet microscopy, we quantified immediate early gene Fos expression in V1 and LM, identifying deficits in experience-dependent neural activity in FX mice. We performed simultaneous in vivo recordings with silicon probes in V1 and LM of awake mice and channelrhodopsin-2-assisted circuit mapping (CRACM) in acute brain slices to examine the neural activity and strength of long-range synaptic connections between V1 and LM in both wildtype (WT) and Fmr1 knockout (KO) mice, the model of FX, before and after visual experience. Our findings reveal synchronized familiarity-evoked theta oscillations in V1 and LM, the increased strength of V1→LM functional and synaptic connections, which correlated with the corresponding changes of presynaptic short-term plasticity in WT mice. The LM oscillations were attenuated in FX mice and correlated with impaired functional and synaptic connectivity and short-term plasticity in the feedforward (FF) V1→LM and feedback (FB) LM→V1 pathways. Finally, using 4Pi single-molecule localization microscopy (SMLM) in thick brain tissue, we identified experience-dependent changes in the density and shape of dendritic spines in layer 5 pyramidal cells of WT mice, which correlated with the functional synaptic measurements. Interestingly, there was an increased dendritic spine density and length in naïve FX mice that failed to respond to experience. Our study provides the first comprehensive characterization of the role of visual experience in triggering inter-areal neural synchrony and shaping synaptic connectivity in WT and FX mice.

Anatomical-related factors and outcome of percutaneous short-term spinal cord stimulation electrode shift in patients with disorders of consciousness: a retrospective study.

Disorders of consciousness (DoC) represent a spectrum of neurological conditions that pose significant treatment challenges. Percutaneous short-term spinal cord stimulation (SCS) has emerged as a promising experimental diagnostic treatment to assess and potentially improve consciousness levels. However, the effectiveness of this intervention is frequently compromised by the shift of electrodes, particularly in the cervical region, which can negatively affect therapeutic outcomes. This retrospective study aimed to study if electrodes shift in percutaneous short-term SCS in patients with DoC would affect the outcome. We analyzed the relationship between electrode shift length and patient outcome, as well as the correlation with various anatomical parameters, including the actual length of the cervical spine, linear length, spinal canal transverse diameter, spinal canal diameter, and C2 cone height, in a cohort of patients undergoing the procedure. Our findings revealed that in patients with better outcome, there are significant less patient with electrode shift (p = 0.019). Further, a linear correlation was found between the length of electrode shift and patients' outcome (Rho = 0.583, p = 0.002), with longer shift lengths associated with poorer outcomes. Contrary to our expectations, there was no significant association between the measured anatomical parameters and the extent of electrode shift. However, a trend was found between the actual length of the cervical spine and the shift of the electrode (p = 0.098). Notably, the shorter spinal canal transverse diameter was found to be significantly associated with better outcome in patients with DoC receiving percutaneous short-term SCS (p = 0.033). These results highlight the clinical importance of electrode stability in the cervical region during SCS treatment for patients with DoC. Ensuring secure placement of electrodes may play a crucial role in enhancing patients' outcome and minimize postoperative complications. Given the lack of association with expected anatomical parameters, future research should investigate other factors that could impact electrode stability to optimize this therapeutic intervention.

Modeling Fragile X Syndrome: Characterizing Fmr1 Gene Knockout Mice across Genotype, Behavior, and Morphology

ABSTRACT Objective: Fragile X syndrome (FXS) is a hereditary condition resulting from dynamic mutations in the Fmr1 gene, leading to reduced or absent fragile X mental retardation protein (FMRP). Although molecular genetic diagnostics for FXS have advanced, there is currently a lack of effective clinical treatment. Hence, identifying a suitable FXS animal model is crucial for FXS therapeutic studies. This study primarily aims to evaluate whether Fmr1 mice display aberrant behaviors similar to those observed in human FXS patients, aiming to validate their feasibility as a model for FXS. Research Design and Methods: Polymerase chain reaction and immunoblotting were employed to genotype Fmr1 knockout (KO) mice and wild-type (WT) mice. Using hematoxylin and eosin staining and Golgi staining, testicular and dendritic spine morphology in both animal groups was observed. The animals were subjected to audiogenic seizure (AGS) observation, evaluating their learning and memory levels using the water maze and light avoidance methods, while their exploratory behavior capacity was assessed using the open-field and autonomous activity experiments. Anxiety behavior was evaluated using the elevated plus maze. Results: WT mice produced a 500 bp DNA fragment, while KO mice yielded an 800 bp fragment. KO mice exhibited a lack of FMRP expression, notably increased dendritic spine length and density, and presented with macroorchidism. KO mice showed increased susceptibility to AGS. In the Morris water maze experiment, KO mice displayed significantly increased escape latency and platform crossings. The spatial search experiment revealed that KO mice spent significantly less time in the target quadrant compared to WT mice. The light-avoidance and platform experiments indicated a significant reduction in latency for KO mice but an increase in errors. In the open-field experiment, KO mice spent significantly more time and made more entries into the central zone compared to WT mice. KO mice exhibited increased total travel distance and speed. The elevated plus maze experiment showed that KO mice spent significantly more time, made more entries, and traveled further in the open area compared to WT mice. The autonomous activity experiment revealed that KO mice had significantly more activity counts than WT mice but fewer standing counts. Conclusions: Findings from genotype, protein expression spectrum, morphology, and behavioral results suggest that Fmr1 gene KO mice demonstrate phenotypes similar to those observed in human FXS, making them a potential model for future FXS research. These phenotypes are associated with the absence of FMRP expression.

Gadd45A-mediated autophagy regulation and its impact on Alzheimer's disease pathogenesis: Deciphering the molecular Nexus

BackgroundThe growth arrest and DNA damage-inducible 45 (Gadd45) gene has been implicated in various central nervous system (CNS) functions, both normal and pathological, including aging, memory, and neurodegenerative diseases. In this study, we examined whether Gadd45A deletion triggers pathways associated with neurodegenerative diseases including Alzheimer's disease (AD). MethodsUtilizing transcriptome data from AD-associated hippocampus samples, we identified Gadd45A as a pivotal regulator of autophagy. Comprehensive analyses, including Gene Ontology enrichment and protein-protein interaction network assessments, highlighted Cdkn1A as a significant downstream target of Gadd45A. Experimental validation confirmed Gadd45A's role in modulating Cdkn1A expression and autophagy levels in hippocampal cells. We also examined the effects of autophagy on hippocampal functions and proinflammatory cytokine secretion. Additionally, a murine model was employed to validate the importance of Gadd45A in neuroinflammation and AD pathology. ResultsOur study identified 20 autophagy regulatory factors associated with AD, with Gadd45A emerging as a critical regulator. Experimental findings demonstrated that Gadd45A influences hippocampal cell fate by reducing Cdkn1A expression and suppressing autophagic activity. Comparisons between wild-type (WT) and Gadd45A knockout (Gadd45A−/−) mice revealed that Gadd45A−/− mice exhibited significant cognitive impairments, including deficits in working and spatial memory, increased Tau hyperphosphorylation, and elevated levels of kinases involved in Tau phosphorylation in the hippocampus. Additionally, Gadd45A−/− mice showed significant increases in pro-inflammatory cytokines and decreases autophagy markers in the brain. Neurotrophin levels and dendritic spine length were also reduced in Gadd45A−/− mice, likely contributing to the observed cognitive deficits. ConclusionsThese findings support the direct involvement of the Gadd45A gene in AD pathogenesis, and enhancing the expression of Gadd45A may represent a promising therapeutic strategy for the treatment of AD.

The evolution of body posture in the sagittal plane in the sensitive growth period of children and adolescents undergoing individual scoliosis therapy: A pilot study

Introduction: The shape of the spine in the sagittal plane undergoes evolution, which occurs specifically in children and adolescents with idiopathic scoliosis (IS). The aim of the study was to verify the variability of body features and indicators in relation to the features and parameters of body posture in children and adolescents with IS. Materials and Methods: 61 measurements of children and adolescents (three age groups) with IS were collected. Body height, body weight, waist circumference, hip circumference, scoliosis major curve angle, thoracic kyphosis angle, lumbar lordosis angle, spine length, and pelvic tilt were measured. BMI and WHtR were calculated. Results: The progression of characteristics and indices of body physique and changes in body proportions with age significantly affects the flattening of lumbar lordosis and pelvic tilt. At the same time, an inverse relationship between lumbar lordosis angle and scoliosis major curve in children and adolescents was found. There was a weak correlation of kyphosis with body characteristics and indices. Conclusions: Among children and adolescents with adolescent IS, the parameters of the pelvis and lumbar lordosis angle are independent of the thoracic kyphosis angle, and therefore, thoracic kyphosis can be described as a structural parameter, characteristic of scoliotic deformity.

New species of Batrochoglanis Gill (Siluriformes: Pseudopimelodidae) from the Capim River basin, State of Pará, Brazil

Batrochoglanis labrosus new species, is described from the Capim River Basin, State of Pará, Brazil. The new species differs from congeners by the stout, inferior mandible, hypertrophied lips on the lateral of the mouth, a broad dark brown band extending dorsoventrally from the beginning of the trunk to the posterior third of the adipose fin followed by a second dark brown band on the caudal peduncle, dark brown pelvic fin, and caudal fin hyaline with a concentration of dark brown spots on the posterior margin, sometimes forming an irregular band. The morphometric variables of B. labrosus are similar in B. villosus and B. castaneus, forming a B. villosus species group. The B. villosus group is distinct from other group formed by B. acanthochiroides and B. transmontanus in the third axis of the Principal Components Analysis. The variables with higher positive loadings in the B. villosus group, representing larger measurements, were adipose-fin base length, eye diameter, maxillary barbel length, head depth, and mouth width; the higher negative loadings representing shorter measurements were pelvic fin to anal fin distance and pectoral-fin spine length. The species is known only from the Capim River basin, where it is possibly endemic.

Evaluation of ERAS protocol implementation on complex spine surgery complications and length of stay: a single institution study

BACKGROUND CONTEXTWith the goal of improving patient outcomes, the Integrated Spine Center at UT Southwestern Medical Center implemented an enhanced recovery after surgery (ERAS) protocol which includes pre- and postsurgery guidelines. Numerous studies have shown benefit of implementation of ERAS protocols to standardize perioperative care in line with best practices; however, the literature on complication rates, LOS, and readmissions shows mixed results. PURPOSEThe goal of this study was to investigate the impact of the ERAS protocol implementation on complication rates in the perioperative period, as well as hospital and ICU length of stay and hospital re-admission rates. STUDY DESIGN/SETTINGA retrospective cohort study was performed on all patients who underwent spine surgery between September 2016 and September 2021 at a single institution. Patients who met inclusion criteria were divided into non-ERAS and ERAS groups, and comparative statistics were used to evaluate ERAS protocol effectiveness. PATIENT SAMPLEAll patients who underwent spine surgery at UT Southwestern between September 2016 and September 2021 were evaluated for inclusion in the study. The patient sample was further refined to include only complex patient cases which were able to receive the full ERAS protocol (nonemergent admissions). OUTCOME MEASURESPresence of absence of postoperative complications including surgical site infection, AKI, DVT, MI, sepsis, pneumonia, PE, stroke, shock, and other complications were compared between groups, as were hospital and ICU length of stay, and 7, 30, and 90 day readmissions. Self-reported or functional measures were not used in outcome evaluation. METHODSA database of patient and surgery characteristics was built using an EMR query tool with spot checks performed by the authors. Control and treatment groups were matched for gender, age, BMI, ASA score, and surgery type. Total number of complication rates was compared between ERAS and non-ERAS groups, and comparative statistics were used to determine significance. RESULTSSignificant differences between ERAS versus non-ERAS groups were found in rates of UTI (6.8% vs 3.1%, respectively; p=.031), constipation (20.6% vs 11.4%, respectively; p=.001), and any complications (31.4% vs 19.4%, respectively; p<.001). There was no significant difference in the rates of other complications, in length of hospital or ICU stay, or readmissions at 7, 30, and 90 days. CONCLUSIONSImplementation of the ERAS protocol did not decrease complication rates or length of stay, and ERAS patients had significantly higher rates of UTI, constipation, and any complications. There may have been confounding factors due to the impact of COVID-19 on delivery of care, as well as misalignment between ERAS goals and outcome measures.

Growth modulation response in vertebral body tethering depends primarily on magnitude of concave vertebral body growth

PurposeThere is variability in clinical outcomes with vertebral body tethering (VBT) partly due to a limited understanding of the growth modulation (GM) response. We used the largest sample of patients with 3D spine reconstructions to characterize the vertebra and disc morphologic changes that accompany growth modulation during the first two years following VBT.MethodsA multicenter registry was used to identify idiopathic scoliosis patients who underwent VBT with 2 years of follow-up. Calibrated biplanar X-rays obtained at longitudinal timepoints underwent 3D reconstruction to obtain precision morphological measurements. GM was defined as change in instrumented coronal angulation from post-op to 2-years.ResultsFifty patients (mean age: 12.5 ± 1.3yrs) were analyzed over a mean of 27.7 months. GM was positively correlated with concave vertebra height growth (r = 0.57, p < 0.001), 3D spine length growth (r = 0.36, p = 0.008), and decreased convex disc height (r = − 0.42, p = 0.002). High modulators (patients experiencing GM > 10°) experienced an additional 1.6 mm (229% increase) of mean concave vertebra growth during study period compared to the Poor Modulators (GM < − 10°) group, (2.3 vs. 0.7 mm, p = 0.039), while convex vertebra height growth was similar (1.3 vs. 1.4 mm, p = 0.91).ConclusionWhen successful, VBT enables asymmetric vertebra body growth, leading to continued postoperative coronal angulation correction (GM). A strong GM response is correlated with concave vertebral body height growth and overall instrumented spine growth. A poor GM response is associated with an increase in convex disc height (suspected tether rupture). Future studies will investigate the patient and technique-specific factors that influence increased growth remodeling.

Morphological and life‐history trait plasticity of two Daphnia species induced by fish kairomones

AbstractDaphnia can avoid predation by sensing fish kairomones and producing inducible defenses by altering the phenotype. In this study, the results showed that the morphological and life‐history strategies of two Daphnia species (Daphnia pulex and Daphnia sinensis) exposed to Aristichthys nobilis kairomones. In the presence of fish kairomones, the two Daphnia species exhibited significantly smaller body length at maturity, smaller body length of offspring at the 10th instar, and longer relative tail spine of offspring. Nevertheless, other morphological and life‐history traits of the two Daphnia species differed. D. pulex showed a significantly longer relative tail spine length and earlier age at maturity after exposure to fish kairomones. The total offspring number of D. sinensis exposed to fish kairomones was significantly higher than that of the control group, whereas that of D. pulex was significantly lower. These results suggest that the two Daphnia species have different inducible defense strategies (e.g., morphological and life‐history traits) during prolonged exposure to A. nobilis kairomones, and their offspring also develop morphological defenses to avoid predation. It will provide reference for further exploring the adaptive evolution of Daphnia morphology and life‐history traits in the presence of planktivorous fish.

A Fast Online Elastic-Spine-Based Stiffness Adjusting Mechanism for Fishlike Swimming.

Fish tunes fishtail stiffness by coordinating its tendons, muscles, and other tissues to improve swimming performance. For robotic fish, achieving a fast and online fishlike stiffness adjustment over a large-scale range is of great significance for performance improvement. This article proposes an elastic-spine-based variable stiffness robotic fish, which adopts spring steel to emulate the fish spine, and its stiffness is adjusted by tuning the effective length of the elastic spine. The stiffness can be switched in the maximum adjustable range within 0.26 s. To optimize the motion performance of robotic fish by adjusting fishtail stiffness, a Kane-based dynamic model is proposed, based on which the stiffness adjustment strategy for multistage swimming is constructed. Simulations and experiments are conducted, including performance measurements and analyses in terms of swimming speed, thrust, and so on, and online stiffness adjustment-based multistage swimming, which verifies the feasibility of the proposed variable stiffness robotic fish. The maximum speed and lowest cost of transport for robotic fish are 0.43 m/s (equivalent to 0.81 BL/s) and 7.14 J/(kg·m), respectively.